Title of Invention

TONER, IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD

Abstract TONER, IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD The present invention relates to a toner comprising a toner material, wherein the toner satisfies the following formula: 5 °C ≤ ΔTm ≤ 20 °C; where ΔTm represents Tma - Tmb, Tma (°C) is 1/2 flown-out temperature of the toner by a capillary type flow tester, and Tmb (°C) is 1/2 flown-out temperature of a melt kneaded mixture of the toner by the capillary type flow tester, and wherein Tma is from 130°C to 200°C; the toner has a core-shell structure; and the 1/2 flown out temperatures Tma and Tmb represent the temperature at which a 1/2 of the toner and a 1/2 of the melt kneaded mixture of the toner flow out, respectively, and that they are measured at conditions with a load of 30 kg, die diameter of 1 mm and a temperature rising rate of 3°C/min. The invention also discloses an image forming apparatus and an image forming method using the above toner. FIG. 22
Full Text Technical Field
The present invention relates to toners for developing electrostatic
images of electrophotography, electrostatic recording, electrostatic printing, and
the like; and to developers, toner containers, process cartridges, image forming
apparatuses, and image forming methods using the toners.
Background Art
Image formation by e.g. electrophotographic method is generally carried
out by a series of processes including forming a latent electrostatic image on a
photoconductor (latent electrostatic image bearing member),' developing the
latent electrostatic image by a developer containing a toner to form a visible
image (toner image),' then transferring the visible image to a recording medium
such as paper," and fixing the image to form an fixed image.
The toner is a colored particle comprising a binder (binder resin),
colorant, charge controlling agent, etc. which are contained in the binder. As
the method for producing the toner, pulverization and suspension
polymerization are mainly known.
The pulverization is a method for producing a toner in which a colorant,

charge controlling agent, etc. are melt-mixed and are uniformly dispersed into a
binder to obtain a toner composition, and the obtained toner composition is
grinded, classified, etc. to form a toner. The pulverization has drawbacks as
follows. Specifically, a grinder, etc., are required to grind a toner composition,
resulting in high cost, and thus the method is not effective. In addition, during
the grinding, toner particles with wide distribution of particle diameter tend to
be formed. Therefore, in order to obtain images with high resolution and high
gradation, a portion of the toner particles, for example, minute particles of 5 µm
or less in diameter and large grains of 20 µm or more, must be removed by
classification, inviting a significant reduction of yield. Furthermore, it is
difficult to disperse additives such as a colorant, and charge controlling agent
into the binder uniformly. The use of the toner in which the additives are not
dispersed uniformly deteriorates flowability, developability, durability, image
quality, etc.
Recently, to overcome these problems in pulverization, a method for
producing a toner by polymerization of monomer is proposed and carried out.
For example, toner particles are produced by suspension polymerization.
However, toner particles obtained by suspension polymerization are generally
spherical and have drawback of poor cleaning ability. Poor cleaning ability
causes non-transferred residual toner on a photoconductor, and the
accumulation of such residual toner leads to background smear. Moreover,
residual toner oontaminates components such as a charging roller, which

charges a photoconductor by contact charging, and subsequently reduces the
charging performance of the charging roller.
Therefore, a method for producing toner particles is proposed in which
emulsion polymerization is used to form resin fine particles, which are
subsequently associated to obtain toner particles having irregular shapes (See
Patent literature 1). However, toner particles formed by emulsion
polymerization have residual surfactants in large amounts inside the particles
as well as on the surface thereof, even after being washed by water. As a result,
charge stability of toner is reduced, the distribution of the amount of charge is
increased, causing background smear on a printed image. In addition, the
residual surfactant contaminates photoconductor, charging roller, developing
roller, etc. Therefore, toner cannot fulfill its original function.
On the other hand, for the fixing process by contact heating, in which
heating members such as a heating roller are used, the toner particles must
possess releasability, which may be referred to as "offset resistance" hereinafter,
from the heating members. In such case, offset resistance can be improved by
allowing a releasing agent to exist on the surface of toner particles. In contrast,
methods to improve offset resistance are disclosed in which resin fine particles
are not only contained in toner particles, but are concentrated at the surface of
the toner particles (See Patent Literatures 2 and 3).
These proposals, however, cause increase of lowest fixing temperature,
resulting in unsatisfactory fixing ability at low temperatures, i.e. energy-saving

fixing ability. In addition, this method, in which resin fine particles obtained
by emulsion polymerization are associated to provide irregularshaped toner
particles, has another problem. Generally, releasing agent particles are
additionally associated to improve the offset resistance. However, the releasing
agent particles are captured inside the toner particles and therefore the
improvement of the offset resistance is not sufficient. Moreover, since each
toner particle is formed by a random adhesion of molten resin fine particles,
releasing agent particles, colorant particles, and the like, the composition (the
ratio at which each component is contained), molecular mass of the resin, and
the like may be different and dispersed for each obtained toner particle. In
result, the surface properties of toner particles are different from one another,
and it is impossible to form stable images for a long period. Additionally, in a
low-temperature fixing system, the resin fine particles that are concentrated at
the surface of the toner particles inhibit fixing and therefore the range of fixing
temperature is not sufficient.
Recently, a new method for producing a toner, called solution suspension
method (Emulsion-aggregation method (EA method), has been suggested (See
Patent Literature 4). In this method, particles are formed from polymers that
are dissolved in an organic solvent or the like whereas in suspension
polymerization, polymer particles are formed from monomers, and the method is
advantageous in that, for example, there is a larger selection of resins that can
be used and polarity can be controlled. Furthermore, the method is

advantageous in that it is possible to control the structure of toner particles
(core/shell structure control). However, the shell structure is a layer consisting
only of a resin and the purpose thereof is to lower the exposure of pigment and
wax to the surface. The purpose is not to alter the structure in the resin, and
the structure is not capable for such purpose (See Non-Patent Literature 1).
Therefore, although the toner particle has a shell structure, the surface of the
toner particle is a usual resin without any ingenious feature so that when the
toner particle is targeted at fixing at a lower temperature, there is a problem
that it is not satisfactory from the standpoint of anti-heat preservability and
environmental charge stability.
In any of the conventional methods such as the suspension
polymerization, emulsion polymerization, and solution suspension,
styrene-acrylic acid ester copolymer is used as a binder resin in many cases.
Polyester resins are not generally used because they are difficult to be made into
particles, it is uneasy to control particle diameter, diameter distribution, particle
shape, etc., and their fixing ability is insufficient under the condition of fixing at
a lower temperature.
In pulverization, in order to achieve fixing at low temperatures, a
polyester resin having a high acid value is used. For example, Patent
Literature 5 and Patent Literature 6 propose toners comprising a resin of which
acid value, hydroxyl value, molecular mass distribution, THF insoluble content,
or the like, are defined. The toner in these proposals, however, causes the

reduction of melting temperature at the same time, resulting in the
deterioration of offset resistance. In order to achieve all of fixing property at
low temperatures, offset resistance and anti-heat preservability, further
improvement is needed.
Much work has been done from various angles of approach in the field of
electrophotography to improve quality, and it is being recognized that it is
extremely effective to reduce the size and increase the sphericity of the toner
particle. However, as the diameter of toner particles becomes smaller, the
transferability and fixing ability tend to decrease, and image quality becomes
poor. Especially, with respect to fixing, fixing ability at a halftone portion
becomes worse. This is because at the halftone portion, the adhesive amount of
toner is low, the toner, transferred to the concave portion on a transfer material,
is given extremely small amount of heat from a fixing roller, causing generation
of offset phenomenon easily. In addition, it is known that by making toner
particles round, the transferability rises (See Patent Literature 7).
In such situation, ever-faster image production is desired in the field of
color copiers and printers. For a faster printing, the "tandem method" is
effective (See Patent Literature 8). The "tandem method" is a method in which
images formed by respective image forming units are overlaid and sequentially
transferred onto a sheet of paper that is advanced by a transfer belt so that a
full-color image is obtained on the sheet. In a color image forming apparatus
using tandem method, various kinds of paper can be used, the quality of

full-color images is high, and full-color images can be formed at high speed.
The high-speed output of full-color images is especially characteristic and no
other color image reproduction machines have that characteristic. There are
other attempts to increase speed while improving the quality by using round
toner particles. In order to increase speed more, the round toner is required to
be fixed quickly; however, in a present situation, such round toner that has both
quick fixing ability and fixing ability at low temperature has not been achieved.
Toner may be subjected to severe circumstances such as high
temperature and humidity, and low temperature and humidity during storage
and transport after the production. There has been a demand for a toner which
does not aggregate to each other, of which flowability, transferability, and fixing
ability do not deteriorate or rarely do, and which has excellent preservability,
even after storage for a long period under such circumstances. However, in the
present situation, effective means for such demand has not been found
especially with respect to spherical toner.
In electrophotographic system, a heat-pressure fixing method by means
of a heating roller is conventionally used. In the method, while the surface of a
heat roller possessing releasability for a toner is brought contact with the toner
image on the surface of a receiving sheet under pressure, the receiving sheet is
allowed to pass through to thereby fix the toner image. In this method, the
surface of the heat roller and toner image on the receiving sheet are brought into
contact with each other under pressure. Thus, heat efficiency during the

melt-fixing of toner image on the receiving sheet is extremely satisfactory, which
enables quick fixation.
By the way, in the heat pressure fixing method by means of a heating
roller, the surface of the heating roller and toner image are brought into contact
with each other in a melted state and under pressure. A portion of toner image
is transferred to the surface of fixing roller to adhere, and the transferred
portion of toner image is re-transferred to the next receiving sheet, leading to
the pollution of the receiving sheet. This so-called offset phenomenon is greatly
influenced by the fixing speed and fixing temperature. This is because almost
constant amount of heat for fixing toner is given to toner without depending on
the fixing speed.
In general, when the fixing speed is slow, the surface temperature of
heating roller is set to relatively low temperature. In contrast, when the fixing
speed is fast, the surface temperature of heating roller is set to relatively high
temperature.
The toner on the receiving sheet forms several toner layers. Thus,
particularly, in a system where fixing speed is fast, the surface temperature of
heating roller is high an uppermost layer of toner layers which contacts with a
heating roller and a lowermost of toner layers which contacts with the receiving
sheet temperature difference becomes large. Therefore, when the surface
temperature of heating roller is high, the toner of the uppermost layer tends to
cause offset phenomenon, and when the surface temperature of heating roller is

low, toner does not fix to the receiving sheet because the toner of the lowermost
layer does not melt sufficiently, causing low-temperature offset phenomenon
easily.
As a way to solve this problem, when the fixing speed is fast, a method
is normally carried out in which pressure during fixing is increased, making the
toner to be anchored to the receiving sheet. This method can reduce heating
roller temperature to some degree, and can prevent high-temperature offset
phenomenon of the uppermost layer of toner layers. However, shearing force
on the toner becomes very large, receiving sheet winds around the fixing roller,
i.e., so-called winding offset occurs, and a trace of separating pawls for
separating the receiving sheet from the fixing roller is likely to appear on a fixed
image. Further, inferior fixed images are likely to occur, such as such as failure
of line images during fixing and toner scattering, due to a high pressure.
Moreover, in a high-speed fixing system, a toner having a lower melt
viscosity is generally used than in the case of low speed fixation, and the surface
temperature of the heating roller and fixing pressure are lowered. Thus, a
toner image is fixed while obviating the high-temperature offset and winding
offset. However, the use of such a toner having a low melt viscosity in low
speed fixation is likely to cause an offset phenomenon at high temperature.
Accordingly, in fixing, there has been demand for a toner which shows a
wide fixable temperature range and excellent offset resistance and is applicable
from a low-speed apparatus to a high-speed apparatus.

In order to obtain high quality image, an attempt to make the size of
toner particles smaller has been made. Smaller particle size toner increases
the resolution and clearness of an image, but impairs the fixability of a halftone
image. This phenomenon is particularly noticeable in high-speed fixation.
This is because the adhesive amount of toner in a halftone part is small and the
toner transferred to a concave portion of a receiving sheet receives only a small
quantity of heat from a heating roller and the pressure applied thereto is also
suppressed because of the convex portion of the receiving sheet. The toner
transferred onto the convex portion of the receiving sheet in a halftone part
receives a larger shearing force per toner particle because of thin toner layer
thickness, compared with that in a solid image part with thick toner layer
thickness. Thus, offset phenomenon is likely to be caused and fixed image is
likely to have low quality.
Until now, in order to pursue fixing performance and anti-hot offset, a
variety of studies, mainly on binder resin, have been made. For example,
Patent Literature 9 proposes resin having a molecular mass distribution such
that the distribution has at least one local maximal value in each of the region of
a molecular mass of 103 to 7x104 and the region of a molecular mass of 105 to
2x106 in a chromatograph by gel permeation chromatography (GPC) of resin for
toner. Further, in Patent Literature 10 and Patent Literature 11, the
molecular mass distribution of vinyl copolymer is defined and releasing agent
such as polyethylene is added to pursue fixing ability and hot offset.

Furthermore, in Patent Literature 12, by combining a resin having low viscosity
with resin having high viscosity, an attempt to improve fixing property at low
temperatures and hot offset property simultaneously is made. In other Patent
Literatures, many techniques have been proposed that pursue optimization of
balance of preservability, fixing ability, and hot offset that are difficult to pursue
simultaneously by widening the molecular mass distribution of binder resin (See
e.g. Patent Literature 10, Patent Literature 11, and Patent Literatures 13 to
16).
In electrophotography, anti-heat preservability, which is influenced by
elements with a low molecular mass, must be also satisfied besides these two
properties that are difficult to pursue simultaneously. For example, in Patent
Literature 17, attempts to improve anti-heat preservability, etc. by using a
novolac type phenol resin or polyurethane other than molecular mass
distribution have been made.
In these proposals, the effect by defining the molecular mass
distribution or the effect by olefin having low molecular mass improves fixing at
low temperatures and anti-heat preservability; however, these binder resins do
not meet the recent demand for energy-saving and low-power enough and
further investigation has been desired.
In particular, in order to improve fixing property at low temperatures, it
is required to lower the glass-transition temperature (Tg) and molecular mass of
binder resin. However, in the present situation, it is difficult to develop such

toner that satisfies all these properties in light of balance between hot offset
property and preservability.
For example, Patent literature 18 proposes a dry toner containing a
urethane-modified polyester (A) as a toner binder obtained by elongation
reaction and having a practical sphericity of 0.90 to 1.00 in order to improve the
fluidity, fixing property at low temperatures, and hot offset property. Further,
a dry toner is proposed that has excellent powder fluidity and transferability,
although the toner has a small particle diameter, and is also excellent in any of
anti-heat preservability, fixing property at low temperatures, and hot offset
resistance. The dry toner produces glossy images, especially, when used in e.g.
a full-color copier and does not require application of oil to a heat roller.
Although the dry toner proposed by Patent Iiteraturel8 is novel in that
binder obtained as a result of a urethane reaction is employed, it is produced by
a pulverization process and does not have satisfactory fixing ability at low
temperatures. In addition, specific conditions enabling a small particle
diameter and controlling particle shape so as to be spherical are not described.
Moreover, Patent Literature 19 and Patent literature 20 propose a dry
toner comprising a toner binder formed from an elongation and/or a crosslinking
reaction of an isocyanate group containing prepolymer, and a colorant, wherein
the dry toner is formed of particles formed from an elongation and/or a
crosslinking reaction of the modified polyester (A) by amines (B) in an aqueous
medium. Patent literatures 19 and 20 also propose a method for producing

the toner, which is an economically affordable method to obtain a dry toner.
The toners proposed in these Patent Literatures 19 and 20 are prepared
by granulation in water. However, in such granulation in water, a pigment in
an oil phase aggregates at the interface with an aqueous phase, which leads to
decreased volume resistivity or uneven pigment distribution and causes
problems in fundamental properties of the toner, To achieve simultaneously a
small particle diameter and a satisfactorily controlled shape of a toner for use in
a machine without application of oil, the specific shape and/or properties must
be defined and without such specified shape and/or properties, effect cannot be
achieved. However, each Patent Literature dose not describe adequately the
effects of the combination of properties and/or processes or effects of the balance
between detailed conditions, and thus effects on the problems may not be
significantly achieved. Particularly, in the case of toner particles prepared by
granulation in water, pigment and/or wax is likely to gather on the surface of the
particles of toner. Toner particles having a particle diameter of about 6 µm or
less have a large specific surface area, thus design of the particle surface
becomes important for achieving desired charging properties fixing properties in
addition to the design of the polymer component.
In general, conventional electrophotographic image forming apparatus
comprises a heat fixing unit in which a pressure member such as a pressure
roller is brought into contact with a heating member such as heating roller
having a heat source inside thereof, a recording medium on which image has

been transferred is passed therebetween and while the recording medium being
transported, toner images on the recording medium are fixed.
In this type of heat fixing unit, so-called offset phenomenon that toner
on the recording medium adheres to a heating member may occur. It is known
that when this offset phenomenon occurs, offset toner also adheres to the
pressure member, and toner adhered to those heating member and pressure
member is transferred back to a recording medium to contaminate the recording
medium. In order to prevent the occurrence of offset, in a conventional heat
fixing unit, for example, the surface of a heating member was coated with
fluorine. However, it is difficult to prevent offset phenomenon completely
depending on environmental conditions, types of recording medium, etc,
eventually causing reverse transfer.
Therefore, a heat fixing unit is proposed in which a cleaning member
such as cleaning roller is provided in contact with a heating member and
pressure member to thereby remove toner adhered to the heating member and
pressure member. In this heat fixing unit, cleaning member, made of pure
metal material, is brought into contact with a heating member or pressure
member having improved surface releasability, thereby removing toner due to
the difference of surface releasability.
Recently, an image forming apparatus has been constructed in the
following manner in order to prevent a waste of energy. Specifically, during the
standby state, current to the heat source of a heat fixing unit is stopped, only

when image forming starts, current is allowed to flow to the heat source, and the
temperature of the heating member is raised to the fixing temperature.
Therefore, the heating member is required to have improved response to
temperature, for example, a heating roller has a thickness of 1 mm or less,
thereby shortening the time to rise to a fixing temperature to approximately 10
seconds.
In such image forming apparatus, the heating member of a heat fixing
unit has a low thermal capacity, thus heat easily moves to a recording medium
at the time of fixing or to a member contacting with the heating member, or the
heating member is liable to be influenced by the flow of the wind around the
heating member. These cause a problem that the temperature distribution of
the heating member is likely to become uneven in the direction of width.
Therefore, it is impossible to make the temperature distribution even over the
entire region in terms of space and cost.
In a heat fixing unit, uneven temperature distribution of heating
member in the direction of width leads to unstability of fixing performance, and
at the same time, offset is likely to occur. In addition, there is a problem that
deterioration by heat makes the lifetime of a heating member shorter. In
particular, the use of polymerized toner produced by polymerization described in
Patent Literature 18 and Patent Literature 20 causes a problem that tone
adheres to a cleaning member and accumulates thereon, and the masses of
toner melt again and the toner is transferred back to a recording medium. This

is because when pulverized toner produced by pulverization is used, the toner
adhered to the cleaning member has a high storage modulus and is unlikely to
melt; however, when polymerized toner produced by polymerization is used, the
toner adhered to the cleaning member has a low storage modulus, as is expected
to toner produced by polymerization.
This problem is caused especially when recording medium, e.g. a paper,
with small size compared with maximum size to which sheet is run through is
passed through. The reason for this is considered as follows. The passed
region by a recording medium with small size is narrow and thus the contact
area with a heating member is small. Therefore, only the narrow region has
decreased temperature and temperature sensor corresponding to the region
dictates switch-on of a heat source, resulting in unnecessary rise in temperature
of the region where sheet has not passed. This causes the toner on a cleaning
member corresponding to the region where sheet has not passed to melt and be
transferred back.
In attempting to solve such problem of back transfer, Patent literature
21 proposes a heat fixing unit in which in order to make the temperature
distribution of heating roller uniform in the direction of width, wind is applied
thereby preventing the region where sheet has not passed of the heating roller
from having excessively raised temperature.
In addition, Patent Literature 22 proposes a heat fixing unit in which
air holes are provided along a cleaning roller so that air in the heat fixing unit is

circulated with rotation of the cleaning roller to thereby prevent the
temperature of the cleaning roller from being raised.
However, there has not been provided a toner which can fix
satisfactorily immediately after power activation and even under low-power
condition, which has releasability applicable to from low-speed through
high-speed image forming apparatuses, which is excellent in offset resistance,
blocking resistance, and flowability, which does not affect fixing efficiency in a
heat fixing unit, and which is not transferred back when adhered to a cleaning
member, and related techniques. Thus, in the present situation, it has been
desired that such toner and related techniques are provided as soon as possible.
(Patent Literature 1] Japanese Patent (JP-B) No. 2537503
[Patent Literature 2] Japanese Patent Application Laid-Open (JP-A) No.
2000-292973
[Patent Literature 3] JP-A No. 2000292978
[Patent Literature 4] JP-B No. 3141783
[Patent Literature 5] JP-B No. 3141783
[Patent Literature 6] JP-A No. 09-204071
[Patent Literature 7] JP-A No. 09-258474
[Patent Literature 8] JP-A No. 05341617
[Patent Literature 9] JP-A No. 05-107803
[Patent Literature 10] JP-A No. 05-289399
[Patent Literature 11] JP-A No. 05-313413

[Patent literature 12] JP-A No. 05297630
[Patent literature 13] JP-A No. 05-053372
[Patent literature 14] JP-A No. 06-027733
[Patent literature 15] JP-A No. 06075426
[Patent literature 16] JP-A No. 06-118702
[Patent literature 17] JP-A No. 08-146661
[Patent literature 18] JP-A No. 11-133665
[Patent literature 19] JP-A No. 11149180
[Patent literature 20] JP-A No. 2000292981
[Patent literature 21] JP-A No. 9-325550
[Patent literature 22] JP-A No. 2002-123119
[Non-Patent Literature 1] "The characteristics of newly developed toner
and the vision for the future" by Takao Ishiyama, and two others from The 4th
Joint Symposium of The Imaging Society of Japan and The Institute of
Electrostatics Japan on July 29,2000
Disclosure of Invention
A first object of the invention is to provide a toner such that the toner
corresponds to a low-temperature fixing system, is excellent in both of offset
resistance and anti-heat preservability and especially, even after a large number
of copies are to be produced over a long period, the toner does not aggregate to
each other, deterioration of flowability, transferability, and fixing ability is

extremely rare, the toner makes it possible to form stable images on any
transferring medium without transfer errors and with good reproducibility, and
further does not contaminate fixing unit and images, and is also to provide a
developer, toner container, process cartridge, image forming apparatus, and
image forming method using the toner.
A second object of the invention is to provide a toner which can fix
satisfactorily immediately after power activation and even under low-power
condition, which has releasability applicable to from low-speed to high-speed
image forming apparatuses, which is excellent in offset resistance, blocking
resistance, and flowability, which does not affect fixing efficiency in a heat fixing
unit, and which is not transferred back when adhered to a cleaning member,
and is also to provide a developer, toner container, process cartridge, image
forming apparatus, and image forming method using the toner.
A third object of the invention is to provide a toner such that images
with high density and resolution without fogging can be obtained from
low-speed to high-speed image forming apparatuses; and is also to provide a
developer, toner container, process cartridge, image forming apparatus, and
image forming method using this toner.
From a dedicated investigation of relationship between fixing ability,
particularly, offset resistance, and heat characteristic obtained from a capillary
type flow tester that has been carried out by the present inventors to settle
above issues, it is found that the following toner can settle above issues.

Specifically, firstly, the toner has a 1/2 flow beginning temperature, Tma of
130°C to 200°C. Secondly, temperature difference ΔTm, Tma - Tmb, is 0°C to
20°C, wherein Tma is 1/2 flow beginning temperature of the toner and Tmb is
1/2 flow beginning temperature of a melt kneaded mixture of the toner in which
the toner is completely uniformly melted and dispersed by sufficient melting,
shearing, and kneading.
Namely, the primary cause of hot offset is a resin having a low softening
point in the toner, and thus it is important to make this resin to have an
appropriate flow temperature. In addition to above-noted resin, toner typically
also contains a resin having highly cross-linked structure such as a gel
component, releasing agent, etc., and a capillary type flow tester is suitable for
measuring comprehensive flow temperature of these. The higher the heat
characteristic is, especially, the higher the 1/2 flow beginning temperature is, the
better hot offset resistance tends to become; however, the correlation between
them was low. The reason for this is considered, for example, as follows. In
the case of toner having a so-called core/shell structure where a resin having
highly cross-linked structure concentrates on the toner surface and a resin
having a low softening point exists inside the toner; or toner having a seα-island
structure where a gel component is present in a resin having a low softening
point, only measurement of heat characteristic of toner itself is not considered to
be appropriate to know the heat characteristic of the toner at the time when
heat and pressure are sufficiently applied in a fixing section. Therefore, even if

toner having a core/shell structure, as polymerized toner often has, or the like
has a sufficiently high 1/2 flow beginning temperature, the core/shell structure is
destroyed at the time of fixing and a resin having a low melting point flows out
to the outside of the shell, which may cause offset. In contrast, the present
inventors have found that there is a high correlation between: 1/2 flow beginning
temperature of a kneaded mixture of toner in which toner composition is
completely uniformly melted and dispersed by melting, shearing, and kneading
of toner; and hot offset resistance, and particularly, have found that remarkably
high hot offset resistance can be obtained by satisfying the above-mentioned
first and second conditions of the invention.
Further, the present inventors have found that when toner is obtained
by dissolving or dispersing a polymer (prepolymer) that is reactive with an
active hydrogen group containing compound, releasing agent and colorant at
least in an organic solvent to form a toner solution, dispersing the solution or
dispersion in an aqueous medium, reacting the polymer that is reactive with an
active hydrogen group containing compound, after or during the reaction,
removing the organic solvent, washing and drying, the toner improves the effect
of the invention.
In addition, the present inventors further intensively investigated toner
which is excellent in flowability, transferability, fixing ability, hot offset property,
image quality, and anti-heat preservability, which does not affect fixing
efficiency in a heat fixing unit, and which is not transferred back when adhered

to a cleaning roller. As a result, the dry toner described in JP-A Nos. 11-149180
and 2000-292981 is formed of particles formed from an elongation and/or a
crosslinking reaction of the modified polyester (A) by amines (B) in an aqueous
medium and the toner is granulated in water. The dry toner has a particle
structure wherein the particle surface of the toner is moderately coated with a
modified polyester, low Tg polyester and modified polyester are present inside
the particle of toner, wax as a releasing agent is dispersed near the particle
surface, and further, the surface is coated with polymeric resin fine particles
which serves as a surface layer of the toner particle. It realized that in the heat
roller type fixing, a low softening polymer having low heat characteristic inside
the particle bleeds out promptly to contribute to fixing. In addition, it has
found that formation of thin layer made of resin fine particles as a surface layer
of toner enables preservability (especially heat resistance) at the same time due
to control of heat characteristic and molecular mass, in particular, since binder
having a low softening point prevents blocking by its heat.
Moreover, it has found that by the improvement of fixing ability as a
result of allowing toner particle to have a small particle diameter, toner has
fixing property at low temperatures, preservability, fixing property at low
temperatures, releasability, small particle diameter, and highly dispersed
pigment, thereby enabling high image quality.
In normal image output, the toner, adhered to a fixing roller from a
recording paper due to electrostatic offset or the like, is transferred to a pressure

roller at a nip portion where the fixing roller and pressure roller contacts to each
other. The toner adhered to the pressure roller is collected by a cleaning roller
at a nip portion between the pressure roller and cleaning roller. The toner
adhered to the fixing roller through such process is collected by the cleaning
roller and approximately several grams of toner are collected by the cleaning
roller after copied 150,000 sheets.
Here, as shown in FIG. 16, when a toner is adhered to a cleaning roller
600 and a fixing unit 610 is rotated under the heater control of a heater 603
arranged inside of a fixing roller 602 without making a recording paper to pass
through, no problem occurs in the case of pulverized toner composed of
conventional uniform dispersion of pigment, wax, and resin. This is because
the resin used as a binder has a relatively high glass-transition temperature
(Tg), around 60°C, thus the toner, which adheres to a cleaning roller during
cleaning, has a high viscosity, and even if the temperature rises as the number of
copy increases, the adhered toner is unlikely to remelt. This is also because the
temperature at which toner melts doe not vary before and after fixing process
due to uniformity of the adhered toner.
On the other hand, when polymerized toner having a core/shell
structure, as described in JP-A No. 2000-292981, is used, heat is required for
melting polymeric resin of a shell at the time of fixing. However, once toner
undergoes fixing process, the core/shell structure is destroyed, temperature
characteristic of low molecular mass resin, which melts at relatively low

temperature, becomes dominant and the toner tends to melt at lower
temperature than the temperature set for fixing. Therefore, as shown in FIG.
16, when a toner is adhered to a cleaning roller 600 and a fixing unit 610 is
rotated under the heater control of a heater 603 arranged inside of a fixing roller
602 without making a recording paper to pass through, collected toner adversely
remelts and adheres again to the pressure roller 601 and fixing roller 602. If
images are formed with this state, a problem is caused that the remelted toner
adheres to a recording paper, contaminating both sides of the recording paper.
In order to achieve fixing property at low temperatures, this core/shell structure
is very advantageous toner structure in that a resin having a lower
glass-transition temperature (Tg) compared with that of resin in pulverized
toner can be used and that even if low molecular mass resin is used, both of
preservability and fixing property at low temperatures can be pursued.
However, it has found that with respect to adhesion of toner to the fixing
cleaning roller, the adhered toner has a glass-transition temperature (Tg) lower
than that of pulverized toner by about 5°C to about 15°C, the toner adhered to
the cleaning roller remelts due to the heat of fixing roller during copying and is
transferred back to the fixing roller.
Accordingly, the present inventors have developed a toner such that the
toner structure remains to be a core/shell structure, fixing property at low
temperatures and preservability, hot offset property, and prevention of
remelting of toner from a cleaning roller of a fixing roller are pursued at the

same time, and further the toner enables images with high resolution.
Specifically, it has found that the toner including a toner material and
has resin fine particles on the surface thereof, wherein the toner has a
glass-transition temperature (Tg) of 30°C to 46°C, the resin fine particles have a
glass-transition temperature (Tg) of 50°C to 70°C, when the toner is masticated
with Labo Plastomill, the 1/2 flown-out temperature is 95°C to 120°C, and before
the toner is masticated, 1/2 flown-out temperature is 120°C to 145°C, is unlikely
to cause remelting of toner and can satisfy fixing property at low temperatures
and hot offset property.
The invention is based on the above-mentioned findings by the present
inventors and the means for solving the problems are as follows. Specifically,
A toner including a toner material, wherein the toner satisfies the
following formula:
0°C≤ΔTm≤20°C
where ΔTm represents Tma - Tmb, Tma (°C) is 1/2 flown-out
temperature of the toner by a capillary type flow tester, and Tmb (°C) is 1/2
flown-out temperature of a melt kneaded mixture of the toner by the capillary
type flow tester, and
wherein Tma is from 130°C to 200°C.
The toner according to the , wherein the toner satisfies the
following formula:


where ΔTm represents Tma - Tmb, and
wherein Tma is from 130°C to 200°C.
The toner according to the , wherein the toner satisfies the
following formula:

where ΔTm represents Tma - Tmb, and
wherein Tma is from 145°C to 180°C.
The toner according to any one of the to , wherein a
tetrahydrofuran (THF) insoluble content (gel content) in the toner is from 10%
by mass to 55% by mass.
The toner according to any one of the to , wherein the
molecular mass distribution of the toner measured by gel permeation
chromatography (GPC) has at least one peak in a molecular mass region of
5,000 to 25,000.
The toner according to any one of to , wherein the toner has
a glass-transition temperature, Tg, of 50°C to 70°C,
The toner according to any one of to , wherein the average
circularity of the toner is 0.94 to 0.99.
A toner including a toner material and resin fine particles on a
surface of the toner, wherein the toner has a glass-transition temperature, Tg, of
from 30°C to 46°C, the resin fine particles have a glass-transition temperature,
Tg, of from 50°C to 70°C, and wherein, when the toner has been masticated

with Labo Plastomill, the toner has a 1/2 flown-out temperature of from 95°C to
120°C, and before the mastication of the toner, the toner has a 1/2 flown-out
temperature of from 120°C to 145°C.
The toner according to the , wherein a tetrahydrofuran (THF)
insoluble content (gel content) in the toner is from 5% by mass to 25% by mass.
The toner according to one of the and , wherein, in a
particle size distribution measured by a flow type particle image measuring
apparatus, the content of minute particles having a particle diameter of 2 µm or
less is 15% or less.
The toner according to any one of the to , wherein, in a
distribution of particle diameter measured by a Coulter method, the content of
large grains having a particle diameter of 8 µm or more is 2% by mass or less.
The toner according to any one of the to , wherein, in a
distribution of particle diameter measured by a Coulter method, the content of
minute particles having a particle diameter of 3 µm or less is 2% by mass or less.
The toner according to any one of the to , wherein the
toner has an average circularity of from 0.900 to 0.960 and has a spindle shape.
The toner according to any one of the to , wherein the
average particle diameter of the resin fine particles is 10 nm to 200 nm.
The toner according to any one of the to , wherein the
volume average particle diameter (Dv) of the toner is 3.0 µm to 7.0 µm, and the
ratio of the volume average particle diameter (Dv) to the number average

particle diameter (Dn), Dv/Dn, is 1.25 or less.
The toner according to any one of the to , wherein the
toner is obtained by:
at least one of dissolving and dispersing the toner material including an
active hydrogen group containing compound and a polymer that is reactive with
the active hydrogen group containing compound in an organic solvent to form a
toner solution;
at least one of emulsifying and dispersing the toner solution in an aqueous
medium containing resin fine particles to prepare a dispersion;
reacting the active hydrogen group -containing compound with the polymer
that is reactive with the active hydrogen group containing compound in the
aqueous medium to granulate adhesive base materials; and
removing the organic solvent.
The toner according to the , wherein the adhesive base
material includes a polyester resin.
The toner according to the , wherein the acid value of the
polyester resin is 15 mgKOH/g to 45 mgKOH/g.
The toner according to one of the and , wherein the
polyester resin includes a tetrahydrofuran soluble component and the
tetrahydrofuran soluble component has a molecular mass distribution such that
a main peak is present in a molecular mass region of 2,500 to 10,000 and that
the number average molecular mass thereof is in the range of 1,500 to 15,000.

A developer including the toner of any one of the to .
The developer according to the , which is one of a
one-component developer and a two-component developer.
A toner container including: a container; and the toner of any one
of the to contained therein.
A process cartridge including: a latent electrostatic image bearing
member; and a developing unit configured to develop a latent electrostatic
image on the latent electrostatic image bearing member using the toner of any
one of the to to form a visible image.
An image forming apparatus including: a latent electrostatic
image bearing member; a latent electrostatic image forming unit configured to
form an latent electrostatic image on the latent electrostatic image bearing
member; a developing unit configured to develop the latent electrostatic image
using the toner of any one of the to to form a visible image; a
transferring unit configured to transfer the visible image onto a recording
medium; and a fixing unit configured to fix the transferred image on the
recording medium.
The image forming apparatus according to the , wherein the
latent electrostatic image bearing member includes an amorphous silicon.
The image forming apparatus according to one of the and
, wherein the fixing unit is a heat fixing unit which fixes a toner image on a
recording medium while the recording medium is passed between a heating

member and a pressure member and is transported.
The image forming apparatus according to the , wherein the
heat fixing unit incudes a cleaning member which removes a toner adhered to at
least one of the heating member and the pressure member, and wherein a
surface pressure (roller load/contact area) applied between the heating member
and the pressure member is 1.5xl05 Pa or less.
The image forming apparatus according to one of the and
, wherein the fixing unit includes; a heating member equipped with a heat
generator; a film which contacts with the heating member; and a pressure
member which makes pressure contact with the heating member via the film,
wherein the recording medium, on which an unfixed image is formed after
electrostatic transfer, is passed between the film and the pressure member to
thereby heat and fix the unfixed image.
The image forming apparatus according to one of the and
, wherein the fixing unit includes: a heating roller; a fixing roller arranged
parallel to the heating roller; an endless belt-like toner heating medium; and
a pressure roller, wherein the heating roller includes a magnetic metal and is
heated by electromagnetic induction; the toner heating medium is spanned over
the heating roller and the fixing roller, is heated by the heating roller, and is
rotated by these rollers; the pressure roller is brought into pressure contact with
the fixing roller via the toner heating medium and rolls in the forward direction
towards the toner heating medium to form a fixing nip portion, and wherein a

recording medium, on which an unfixed image is formed after electrostatic
transfer, is passed between the toner heating medium and the pressure member
to thereby heat and fix the unfixed image.
An image forming method including: forming a latent electrostatic
image on a latent electrostatic image bearing member; developing the latent
electrostatic image using the toner of any one of the to to form a visible
image; transferring the visible image onto a recording medium; and fixing the
transferred image on the recording medium.
The image forming method according to the , wherein a
charging member is contacted to the latent electrostatic image bearing member
and a voltage is applied to the charging member to charge the latent
electrostatic image bearing member.
The image forming method according to one of one of the and
, wherein, when developing the latent electrostatic image on the latent
electrostatic image bearing member, an alternate electric filed is applied to a
charging member.
The toner of the invention, in a first aspect, includes toner material,
wherein the toner satisfies the following formula:

where ΔTm represents Tma - Tmb, Tma (°C) is 1/2 flown-out
temperature of the toner by a capillary type flow tester, and Tmb (°C) is 1/2
flown-out temperature of a melt kneaded mixture of the toner by the capillary

type flow tester, and wherein Tma is from 130°C to 200°C. As a result,
although the toner is a polymerized toner having a core/shell structure, the
toner is excellent in both of offset resistance and anti-heat preservability and
especially, even after a large number of copies are to be produced over a long
period, the toner does not aggregate to each other, deterioration of flowability,
transferability, and fixing ability is extremely rare, and the toner makes it
possible to form stable images on any transferring medium without transfer
errors and with good reproducibility.
The toner of the invention, in a second aspect, includes a toner material
and resin fine particles on the surface of the toner, wherein the toner has a
glass-transition temperature (Tg) of from 30°C to 46°C, the resin fine particles
have a glass-transition temperature (Tg) of from 50°C to 70°C, and wherein,
when the toner has been masticated with Labo Plastomill, the toner has a 1/2
flown-out temperature of from 95°C to 120°C, and before the mastication of the
toner, the toner has a 1/2 flown-out temperature of from 120°C to 145°C. As a
result, such toner can be provided that the toner can fix satisfactorily
immediately after power activation and even under low-power condition; has
releasability applicable to from low-speed to high-speed image forming
apparatuses; is excellent in offset resistance, blocking resistance, and
flowability; does not affect fixing efficiency in a heat fixing unit; is not
transferred back when adhered to a cleaning member; and can form images
with high density and resolution without fogging.

The developer of the invention includes the toner according to one of the
first and second aspects of the invention. Therefore, when image formation is
carried out by electrophotographic method using the developer, images with
high quality can be obtained wherein the toner forming the image corresponds
to a low temperature fixing system, is excellent in both of offset resistance and
anti-heat preservability and especially, even after a large number of copies are to
be produced over a long period, the toner does not aggregate to each other,
deterioration of flowability, transferability, and fixing ability is extremely rare,
and the toner makes it possible to form stable images on any transferring
medium without transfer errors and with good reproducibility.
The toner container of the invention includes a container and the toner
according to one of the first and second aspects of the invention contained
therein. Therefore, when image formation is carried out by
electrophotographic method using the developer, images with high quality can
be obtained wherein the toner forming the image corresponds to a
low-temperature fixing system, is excellent in both of offset resistance and
anti-heat preservability and especially, even after a large number of copies are to
be produced over a long period, the toner does not aggregate to each other,
deterioration of flowability, transferability, and fixing ability is extremely rare,
and the toner makes it possible to form stable images on any transferring
medium without transfer errors and with good reproducibility.
The process cartridge of the invention includes a latent electrostatic

image bearing member for bearing a latent electrostatic image and a developing
unit for developing the latent electrostatic image on the latent electrostatic
image bearing member using the toner of the invention to form an visible image.
Because the process cartridge is conveniently detachable onto/from an image
fonning apparatus and uses toner according to one of the first and second
aspects of the invention, clear images with high quality can be obtained wherein
the toner forming the image corresponds to a low temperature fixing system, is
excellent in both of offset resistance and anti-heat preservability and especially,
even after a large number of copies are to be produced over a long period, the
toner does not aggregate to each other, deterioration of flowability,
transferability, and fixing ability is extremely rare, and the toner makes it
possible to form stable images on any transferring medium without transfer
errors and with good reproducibility.
The image forming apparatus of the invention includes: a latent
electrostatic image bearing member; a latent electrostatic image forming unit
configured to form an latent electrostatic image on the latent electrostatic image
bearing member; a developing unit configured to develop the latent electrostatic
image using the toner according to one of the first and second aspects of the
invention to form a visible image; a transferring unit configured to transfer the
visible image onto a recording medium; and a fixing unit configured to fix the
transferred image on the recording medium. In the image forming apparatus,
the latent electrostatic image forming unit forms a latent electrostatic image on

the latent electrostatic image bearing member. The transferring unit transfers
the visible image onto the recording medium. The fixing unit fixes the transfer
image onto the recording medium. As a result, high quality
electrophotographic images can be formed wherein the toner forming the image
corresponds to a low-temperature fixing system, is excellent in both of offset
resistance and anti-heat preservability and especially, even after a large number
of copies are to be produced over a long period, the toner does not aggregate to
each other, deterioration of flowability, transferability, and fixing ability is
extremely rare, and the toner makes it possible to form stable images on any
transferring medium without transfer errors and with good reproducibility.
The image forming method of the invention includes: forming a latent
electrostatic image on a latent electrostatic image bearing member; developing
the latent electrostatic image using the toner according to one of the first and
second aspects of the invention to form a visible image; transferring the visible
image onto a recording medium; and fixing the transferred image on the
recording medium. In the image forming method, the latent electrostatic
image is formed on the latent electrostatic image bearing member in the latent
electrostatic image forming. The visible image is transferred onto the recording
medium in the transferring. The transferred image is fixed on the recording
medium in the fixing. As a result, high quality electrophotographic images can
be formed wherein the toner forming the image corresponds to a
low-temperature fixing system, is excellent in both of offset resistance and

anti-heat preservability and especially, even after a large number of copies are to
be produced over a long period, the toner does not aggregate to each other,
deterioration of flowability, transferability, and fixing ability is extremely rare,
and the toner makes it possible to form stable images on any transferring
medium without transfer errors and with good reproducibility.

Brief Description of ACCOMPANYING Drawings
FIG. 1 is a schematic view showing an example of the process cartridge
of the invention.
FIG. 2 is a schematic diagram of an example of the image forming
apparatus of the invention.
FIG. 3 is a schematic diagram of another example of the image forming
apparatus of the invention.
FIG. 4 is a schematic diagram of another example of the tandem image
forming apparatus of the invention.
FIG. 5 is a schematic diagram of another example of the tandem image
forming apparatus of the invention.
FIG. 6 is a schematic diagram showing an example of the operation of
the image forming method of the invention performed by the image forming
apparatus (tandem color image forming apparatus) of the invention.
FIG. 7 is a partially enlarged schematic diagram of image forming
apparatus shown in FIG. 6.
FIG. 8 is a schematic diagram showing an example of the roller type

contact charger.
FIG. 9 is a schematic view showing an example of the structure of the
photoconductor of the invention.
FIG. 10 is a schematic view showing another example of the structure of
the photoconductor of the invention.
FIG. 11 is a schematic view showing another example of the structure of
the photoconductor of the invention.
FIG. 12 is a schematic view showing another example of the structure of
the photoconductor of the invention.
FIG. 13 is a schematic diagram showing an example of the surf fixing
device of the invention.
FIG. 14 is a schematic cross-section view showing an example of the
fixing unit according to a potential induction heating (IH) process of the
invention.
FIG. 15A is a vertical cross-section view of the heating roller part in the
fixing unit according to an IH process of FIG. 14.
FIG. 15B is a longitudinal cross-section view of the heating roller in the
fixing unit according to an IH process of FIG. 14.
FIG. 16 is a diagram for explaining remelting of toner in a heat fixing
unit.
FIG. 17 is a schematic diagram showing an example of the toner
particle of the invention.

FIG. 18Ais a flow curve for determining 1/2 flown-out temperature by a
flow tester.
FIG. 18B is a flow curve for determining 1/2 flown-out temperature by a
flow tester.
FIG. 19 is a schematic diagram showing an example of the image
forming apparatus of the invention
FIG. 20 is a schematic view showing an example of the heat fixing unit
for use in the image forming apparatus of the invention.
FIG. 21 is a schematic diagram showing an example of the process
cartridge of the invention comprising a two-component developer.
FIG. 22 is a scanning electron microscope (SEM) picture of toner
obtained in Example B-1.
Best Mode for Carrying Out the Invention
(Toner)
The toner of the invention, in a first aspect, comprises toner material,
wherein the toner satisfies the following formula:
0°C≤ΔTm≤20°C where ΔTm represents Tma - Tmb, Tma (°C) is 1/2 flown-out
temperature of the toner by a capillary type flow tester, and Tmb (°C) is 1/2
flown-out temperature of a melt kneaded mixture of the toner by the capillary
type flow tester, and wherein Tma is from 130°C to 200°C.

Here, the toner in the melt kneaded mixture of toner can be melted and
kneaded by any method without limitation if the toner is sufficiently melted,
sheared and kneaded, compositions such as a binder resin and releasing agent
in a toner can be completely and uniformly melted and dispersed by the method
and the method can be appropriately selected according to the purpose.
Examples of the kneading machine include such as a uniaxial extruding
kneader, biaxial extruding kneader, batch-type kneader, and the like. The
kneading temperature is preferably 130°C to 150°C. Conditions of kneading
such as torque, rotation number, and time are preferably such a degree that
molecular chain of the composition of toner such as a binder resin is not cleaved.
The conditions are determined approximately to the degree where gel content in
a toner does not vary between before and after kneading. Details about
measurement of gel content will be described later.
Here, the melt-kneading was carried out as follows. Specifically, batch
type kneading was carried out using a Labo Plastomill 4C 150 type (by Toyo
Seiki Seisaku-sho, Ltd.) and a melt kneaded mixture of toner was obtained.
The toner amount used in kneading was 45 g, the heating temperature was
130°C, the rotation number was 50 rpm, and the kneading time was 15 minutes.
In the toner of the first aspect of the invention, 172 flow beginning
temperature Tma obtained from capillary type flow tester is required to be
130°C to 200°C, preferably 145°C to 180°C. If the Tma is lower than this range,
satisfactory hot offset resistance can not be obtained, besides, anti-heat

preservability may be deteriorated. In addition, toner offset to the fixing
member such as fixing roller is cleaned with e.g. a cleaning device on a fixing
roller, which toner may cause such phenomenon that accumulated toner melts
again and is transferred to fixing member, leading to contamination. Tma
higher than this range is not preferable because offset resistance becomes
extremely satisfactory, but fixing property at low temperatures is impaired, thus
not preferable.
The temperature difference ΔTm between 1/2 flow beginning
temperature of the toner Tma and 1/2 flow beginning temperature of toner
mixture Tmb, in which toner compositions are sufficiently evenly melted and
dispersed by sufficient melting, shearing, and kneading of the toner, is required
to be 0°C to 20°C, preferably 5°C to 20°C, more preferably 7°C to 15°C, most
preferably 7°C to 10°C. Larger temperature difference than this range causes
fusion of resins having a low softening point to a fixing member easily even if the
1/2 flown-out temperature of toner Tma satisfies 130°C to 200°C, and therefore
it is impossible to expect sufficient hot offset resistance. Further, it is required
to have appropriate temperature difference. This indicates that toner has a
core/shell structure, which makes mechanical strength of toner strong and also
has an effect of reducing exposure of wax to the surface, thus enabling
prevention of wax spent. Furthermore, even if resin having low molecular
mass is used in a toner, less contamination of photoconductor, developing
member, carrier, etc. by toner occurs because the resin on the surface serves as a

shell.
Here, the 1/2 flown-out temperature is measured using, for example, a
capillary type flow tester (CFT-500C, by Shimadzu Corporation) and is the value
representing the temperature at the time when half of the sample has flown out.
Measurement was carried out under the condition of Load: 30 kg, Die
diameter: 1 mm, Temperature rising rate: 3°C/min.
Preferably, the toner of the first aspect of the invention has volume
average particle diameter (Dv), volume average particle diameter (DvVnumber
average particle diameter (Dn), average circularity, gel content, molecular mass
peak, glass-transition temperature (Tg), etc. as described below.
The volume average particle diameter (Dv) of the toner is, for example,
preferably 3 µm to 7 µm, more preferably 4 to 7, most preferably 5 to 6. Here,
the volume average particle diameter is defined as: Dv = [(∑(nD3)/ ∑n)1/3, where
n is number of particle and D is particle diameter.
When the volume average particle diameter is less than 3 µm, the toner
of two-component developer is likely to fuse onto the carrier surfaces as a result
of stirring in the developing unit for a long period and the charging capability of
carrier may be deteriorated. On the other hand, one-component developer is
likely to cause filming to the developing roller or fusion to the members such as
blade for reducing toner layers thickness. If the volume average particle
diameter is more than 7 µm, obtaining high-resolution, high-quality images
becomes difficult, and the particle diameter of toner may fluctuate when toner

inflow/outflow is implemented in the developer.
The ratio (Dv/Dn) of the volume average particle diameter (Dv) to the
number average particle diameter (Dn) in the toner is preferably 1.25 or less,
more preferably 1.00 to 1.20, and most preferably 1.10 to 1.20.
When the ratio is 1.25 or less, the toner is likely to have relatively sharp
particle size distribution, thus improving the fixing properties. When the ratio
is less than 1.00, the toner of two-component developer is likely to fuse onto the
carrier surfaces due to stirring in a developing unit for a long period, thereby de
grading charging capability of the carrier or cleaning properties, and
one-component developer is likely to cause filming to the developing roller or
fusion to the member such as blade for reducing toner layer thickness. When
the ratio is more than 1.20, obtaining high-resolution, high-quality images
becomes difficult, and the particle diameter of toner may fluctuate when toner
inflow/outflow is implemented in the developer.
The volume average particle diameter and the ratio (Dv/Dn) of the
volume average particle diameter to the number average particle diameter are
measured using a measuring device for particle size distribution of toner
according to a Coulter counter method. Examples of the measuring device
include a Coulter counter TA-II, and Coulter Multisizer IIe (both by Beckman
Coulter Inc.). In the invention, measurement is carried out using the Coulter
counter TA-II connected with an Interface producing a number distribution and
a volume distribution (by The Institute of Japanese Union of Scientists &

Engineers) and a personal computer PC9801 (by NEC Corporation).
The average circularity can be obtained by dividing the circumference of
an equivalent circle having the same area as the projected area of the shape of
toner particle by the circumference of actual toner particle. For example, the
average circularity is preferably 0.94 to 0.99 and more preferably 0.950 to 0.98.
Preferably, the amount of the particle having an average circularity of less than
0.94 is 15% or less.
When the average circularity is less than 0.94, sufficient transfer
properties or high quality images with no dust may not be obtained. When the
average circularity is more than 0.99, it is likely to cause image smears resulted
from cleaning failures on the photoconductor or transfer belt in the
image-forming system utilizing cleaning blades. Specifically, in the case of
image formation having large image area such as photo graphic images, a
residual toner resulted from forming untransferred images on the
photoconductor due to paper feed failure or the like, is accumulated and causes
background smear on the formed image, or pollutes charging rollers which
contact-charge the photoconductor and inhibit charging rollers to exhibit
original charging ability.
The average circularity is measured, for example, by the optical
detection zone method in which a suspension containing toner is passed through
an image-detection zone disposed on a plate, the particle images of the toner are
optically detected by CCD camera, and the obtained particle images are

analyzed. For example, the flow-type particle image analyzer FPIA-2100 by
Sysmex Corp. may be employed for such method.
The THF insoluble content of toner refers to polymer gel content with a
crosslinked structure. Gel content contained in a toner is preferably 10% by
mass to 55% by mass, more preferably 10% by mass to 40% by mass, and most
preferably 15% by mass to 30% by mass. If the gel content is less than this
range, improvement of hot offset resistance can not be expected. Conversely,
larger gel content may deteriorate fixing property at low temperatures.
Here, the gel content is measured as follows. 1 g of toner is weighed, to
this, 100 g of tetrahydrofuran (THF) is added, and left at 10°C for 20 hours to 30
hours. After 20 hours to 30 hours, gel fraction, THF insoluble components,
absorbs THF as a solvent, and swells to precipitate, and then this is separated
with a filter paper. Separated gel fraction is heated at 120°C for 3 hours,
absorbed THF is volatilized, and then mass is weighed. Thus, gel fraction is
measured.
Preferably, the molecular mass distribution of the toner measured by gel
permeation chromatography (GPC) has at least one peak in a molecular mass
region of 5,000 to 25,000. Molecular mass 8,000 to 20,000 in the molecular
mass distribution is more preferable, most preferably molecular mass 13,000 to
18,000. The toner having molecular mass peak in this range has satisfactory
balance of fixing property at low temperatures and hot offset resistance.
Here, the molecular mass distribution is measured according to the

following method. First, the column inside the heat chamber of 40°C is
stabilized, To the column at this temperature, THF as a solvent is drained at a
current speed of 1ml/minute and 50 µl to 200 µl of THF sample solution of the
toner whereof a sample density is adjusted to 0.05% by mass to 0.6% by mass, is
poured and measured. In the measurement of molecular mass of the sample, a
molecular mass distribution of the sample is calculated from the relationship
between log values of the analytical curve made from several monodisperse
polystyrene standard samples and counted numbers. The standard
polystyrene sample for making analytical curves is preferably the one with a
molecular mass of 6x102, 2.1x102, 4x102 1.75x104, 5.1x104, L1x105, 3.9x105,
8.6x105, 2x106 and 4.48x106 by Pressure Chemical Co. or Toyo Soda
Manufacturing Co., Ltd. and at least using approximately 10 pieces of the
standard polystyrene sample is preferable. A refractive index (RI) detector may
be used for above-mentioned detector.
The glass-transition temperature (Tg) of the toner is not particularly
limited and can be appropriately selected according to the purpose, for example,
preferably 50°C to 70°C, more preferably 55°C to 65°C. In the toner, polyester
resins which underwent a crosslinking reaction and/or an elongation reaction
are existed together, which allows the toner to show satisfactory preservability
although the toner has low glass-transition temperature compared with a
conventional polyester resin.
If the glass-transition temperature (Tg) is less than 50°C, the anti-heat

preservability of toner may be deteriorated. If Tg exceeds 70°C, the fixing
property at low temperatures may not be sufficient.
The glass-transition temperature can be measured using, for example,
TG-DSC system TAS-100 (by Rigaku Denki Co., Ltd.) according to the following
method. Initially, about 10 mg of toner is placed in an aluminum sample vessel.
The vessel is placed on a holder unit, which is then set in an electric furnace.
The sample is heated from room temperature to 150°C at a temperature rising
rate of 10°C/min. After being allowed to stand at 150°C for 10 minutes, the
sample is cooled to room temperature and allowed to stand for 10 minutes.
Then, in a nitrogen flow, DSC measurement is carried out using a differential
scanning calorimeter (DSC) while heating the sample to 150°C at a temperature
rising rate of 10°C/min. Glass-transition temperature (Tg) is determined using
the analyzing system of the TG-DSC system TAS-100 system as a temperature
at the intersection of the base line and a tangential line of the endothermic curve
near the glass-transition temperature (Tg).
The toner of the invention, in a second aspect, comprises a toner
material and resin fine particles on the surface of the toner, wherein the toner
has a glass-transition temperature (Tg) of from 30°C to 46°C, the resin fine
particles have a glass-transition temperature (Tg) of from 50°C to 70°C, and
wherein, when the toner has been masticated with Labo Plastomill, the toner
has a 1/2 flown-out temperature of from 95°C to 120°C, and before the
mastication of the toner, the toner has a 1/2 flown-out temperature of from

120°C to 145°C.
In the toner of the second aspect of the invention, resin fine particles
adhered to the surface of the toner is solider than the resin inside of toner.
Thus, when heat characteristic is measured with a flow tester, the heat
characteristic cannot be evaluated appropriately because of influence of the
resin particles adhered to the surface. Therefore, appropriate evaluation
becomes possible by masticating with certain energy to destroy a layer of resin
fine particles of the surface and by measuring heat characteristic of the toner
layer inside the particle. With respect to the conditions under which toner is
masticated with Labo Plastomill, if shearing energy is high, not only resin
particles on the toner particle surface but also resin molecules of the toner layer
inside the toner particle are cut, making it impossible to achieve goal, that is, to
measure heat characteristic of the toner layer inside the toner. In contrast, if
shearing energy is weak, it is impossible to evaluate due to the influence of resin
fine particles on the surface. Therefore, the condition under which toner is
masticated with Labo Plastomill is such that resin fine particle layer of the toner
surface is destroyed, but the toner layer inside of a toner particle is not destroyed.
Specifically, evaluation is carried out under the following conditions.

Mixer :R60
Temperature : 130°C
Time : 15minutes

Sample amount 45 g
Mixer rotation number: 50 rpm
In the case of pulverized toner, it is not necessary to masticate a toner
because resin fine particles are not adhered to the surface. However, the toner
having a core/shell structure of the invention needs this evaluation because
when the toner is used in a copying machine, this influence of toner surface and
heat characteristic inside of the toner influences largely on fixing quality.
When the toner is masticated with Labo Plastomill, 1/2 flown-out
temperature is 95°C to 120°C. The 1/2 flown-out temperature before the
mastication of toner is 120°C to 145°C.
If the 1/2 flown-out temperature after mastication with the Labo
Plastomill is less than 95°C, hot offset and remelting of toner from a fixing
cleaning roller may be likely to occur. If the 1/2 flown-out temperature exceeds
120°C, remelting of toner is improved, but fixing property at low temperatures is
not satisfactory. The value of flow tester before mastication is a range for
obtaining optimum value after mastication. If this value is not satisfied, it is
difficult to satisfy both fixing property at low temperatures and hot offset
property.
Preferably, THF insoluble content (gel content) contained in the toner of
the second aspect is 5% by mass to 25% by mass. This allows the toner
adhering to a cleaning roller to have high elasticity, making it difficult for the
toner to remelt even if the temperature of the cleaning roller increased. In the

case of conventional toner, remelting of toner was not serious technical problem.
Specifically, it was difficult to make the glass-transition temperature (Tg) below
about 55°C, thus the toner adhering to the cleaning roller of a fixing roller is a
toner having high softening point because resin component having relatively
high glass-transition temperature (Tg) adheres to the cleaning roller.
Therefore, the conventional toner does not remelt easily after the increase of
roller temperature. However, in the case of this capsule-like toner, resin
having low Tg is used in the toner inside the particle in order to enable fixing at
lower temperature. Thus, the toner adhering to the fixing roller is such a toner
having low Tg, leading to easy occurrence of remelting from the cleaning roller,
and this characteristic of the toner is in a trade-off relationship with fixing at
low temperatures. As a result of investigation of this toner adhered to the
fixing cleaning roller, it was found that the adhered toner had remarkable fewer
wax component which was added during initial time. When molecular mass
distribution of the adhered toner was measured by GPC, it was observed that
higher-molecular mass components of resins constituting toner adhered,
indicating that toner components fixing are low-molecular mass components
having affinity to a paper.
In this case, in the heat fixing unit in which a recording medium is
passed through between a heating member and pressure member and while the
recording medium being conveyed, toner images on the recording medium are
fixed, the toner to be fixed adheres to a heating roller in trace amount. The

adhered toner is a component which does not contain wax in the particle, or a
toner component which is a component with high elasticity and cannot fix.
Therefore, conditions under which remelting of toner from the fixing
cleaning roller does not occur are as follows.
(1) The amount of adhering to a roller is as small as possible.
(2) The adhering toner is high-molecular components of toner and when
components with high softening point or components with high elasticity
adhered, the toner does not remelt easily.
(3) Toner in which wax is dispersed uniformly in the particle does not adhere to
a cleaning roller easily.
(4) The sharper the distribution in a particle size distribution is, the less the
adhesion of toner in trace amount occur because heat is uniformly applied to
toner at the time of fixing, thus smaller amount of toner adheres to a fixing
cleaning roller.
It is estimated that fixing to a paper by a roller fixing or belt fixing
begins at an effective temperature of near 70°C to 100°C in recent energy saving
copiers, printers, facsimiles, etc. For enabling melting of toner, toner must
begin to flow near this temperature, thus it is said that toner must be softened
and begin to fix at least near 90°C to 110°C.
However, in order for a toner to be softened at 90°C, glass transition
must be 46°C or less based on preservability data. The glass-transition
temperature (Tg) of such polymer is also relates to molecular mass. Normally,

when the glass-transition temperature (Tg) of toner becomes 46°C or less, fixing
ability becomes satisfactory, but preservability is not satisfied.
Therefore, in the toner of the second aspect of the invention, toner is
designed by a binder so that the toner has a glass-transition temperature (Tg) of
30°C to 46°C, which is extremely low temperature, and resin fine particles
having a glass transition of 50°C to 70°C are present on the surface layer of the
particle by 0.3% by mass to 2.0% by mass relative to toner particle. Particles
uniformly coating toner particles serve as particles constituting pseudocapsule
that protect binder having low softening from heat. The reason for the effect
for hot offset, fixing property at low temperatures, and anti-heat preservability
is that the binder resin of the toner surface has high-molecular mass by a urea
bond resulting from reaction of prepolymer and amines, and part of the surface
has a network structure and adopts three-dimensional structure which is
relative strong to stress.
Further, while resin fine particles having the same heat characteristic
as that of a conventional toner are used on the surface layer of the particle,
inside the particle, polyester resin having low Tg is used as a toner binder,
which is a structure advantageous to fixing property at low temperatures
compared to an uniformly kneaded pulverized toner. FIG. 17 shows this toner
particle model. 620, 621, 622, 623, and 624 represent a toner, resin fine
particle, wax, polyester resin not being modified, and modified polyester resin,
respectively. During fixing, the resin fine particle 621 coating the toner surface

layer must respond to the thermal capacity of the heating roller quickly and
make the toner particle binder soak out of surface layer. The balance between
anti-heat preservability and the degree of soaking out is controlled by the
amount of resin fine particles to be adhered.
Therefore, the average particle diameter of the resin fine particles
adhered to the toner surface is preferably 10 nm to 200 nm. The amount of the
adhering resin fine particles is 0.3% by mass to 2% by mass. If the average
particle diameter is less than 10 nm, the resin fine particles do not work
properly, and if it exceeds 200 nm, the resin fine particles remain thickly on the
surface layer, causing the decrease of fixing ability.
The glass-transition temperature (Tg) of the toner is required to be 30°C
to 46°C, the range enabling lower temperature fixing. If the Tg of the toner is
less than 30°C, the toner is difficult to be made into particle, and if it is more
than 46°C, fixing property at low temperatures may not be obtained effectively.
The glass-transition temperature of the toner can be measured in the
same way as in the first aspect.
Here, the residue rate (adhesion rate) of the resin fine particles can be
measured by analyzing substances not resulting from toner particles but from
resin fine particles with a pyrolysis gas-chromatography mass spectrometer,
and by calculating the peak area. Detector is preferably a mass spectrometer,
but is not particularly limited.
The volume average particle diameter (Dv) of the toner of the second

aspect of the invention is preferably 3.0 µm to 7.0 µm, more preferably 3.0 µm to
6.0 µm. The ratio of the volume average particle diameter (Dv) to the number
average particle diameter (Dn) is preferably 1.25 or less, more preferably 1.00 ≤
Dv/Dn ≤ 1.20. This makes it possible to obtain a toner allowing high resolution
arid quality. This allows the toner to be excellent in any of anti-heat
preservabihty, fixing property at low temperatures, and hot offset resistance.
Particularly, fixing property at low temperatures had been achieved by lowering
Tg; however, there was a limitation for lowering Tg in terms of preservability.
Thus, by making the particle diameter small, further lower temperature fixing
was made possible. On the other hand, if the toner contains particles having a
particle diameter of 8 µm or more in large quantity, not only fixing ability but
also tone is impaired. From the point of quality, 2% by mass or less of the
particles having a particle diameter of 8 urn or more do not cause large
drawback. Further, in a two-component developer, even when toner
inflow/outflow is implemented for a long period, the particle diameter of toner in
the developer fluctuates less, and even in the case of stirring in a developing
device for a long period, satisfactory and stable developability can be obtained.
Generally, it is said that the smaller the particle diameter of toner is, the more
advantageous to produce high resolution and quality images. However, it is
disadvantageous for transferability and cleanability.
When the volume average particle diameter is smaller than the
above-mentioned range, the toner in a two-component developer adheres to the

surface of a carrier due to stirring in a developing device for a long period,
resulting in deterioration of chargeability of the carrier. The toner in a
one-component developer tends to cause filming over a developing roller and
adhere to a cleaning member such as a blade for reducing toner layer thickness.
The particle diameter distribution around 3 µm largely relates to these
phenomena, in particular, when the particles with a particle diameter of 3 µm or
less by Coulter method exceed 2% by mass, it causes adhesion to carrier or
adversely affects stability of charge at high level. In addition, cleanability as
well as shape remarkably deteriorates.
Conversely, when the volume average particle diameter of the toner is
larger than 6.0 µm, exceeding the range defined in the invention, obtaining
high-resolution, high-quality images becomes difficult, and the particle diameter
of toner fluctuates in many cases when toner inflow/outflow is implemented in
the developer. This is also true of the toner with a volume average particle
diameter/number average particle diameter more than 1.20.
The volume average particle diameter and the ration of volume average
particle diameter to the number average particle diameter (Dv/Dn) can be
measured in the same way as in the first aspect.
In the toner of the second aspect of the invention, molecular mass
distribution of the binder component of the toner is measured by the method
shown below. About 1 g of toner is precisely weighed in a conical flask, then 10
g to 20 g of tetrahydrofuran (THF) is added to prepare a THF solution with a

binder concentration of from 5% to 10%. The column inside the heat chamber
of 40°C is stabilized. To the column at this temperature, THF as a solvent is
drained at a current speed of 1ml/minute and 20 µl of THF sample solution is
poured. Molecular mass of the sample is calculated from the relationship
between log values of the analytical curve made from several monodisperse
polystyrene standard samples and retention time. The analytical curve is
prepared using a polystyrene standard sample. The monodisperse polystyrene
standard sample is, for example, a product by Tosoh Corporation, having a
molecular mass of 2.7x102 to 6.2x106. A refractive index (RI) detector can be
used as the detector. The columns are, for example, combinations of TSKgel,
G1000H, G2000H, G2500H, G3000H, G4000H, G5000H, G6000H, G7000H and
GMH, all of which are available from Tosoh Corporation.
THF soluble component has a molecular mass distribution such that a
main peak molecular mass is preferably from 2,500 to 10,000, more preferably
from 2,500 to 8,000, most preferably from 2,500 to 6,000. When the amount of
the component having the molecular mass less than 2,500 is increased,
anti-heat preservability of the resultant toner tends to deteriorate. When the
amount of the component having a molecular mass greater than 10,000 is
increased, fixing property at low temperatures of the resultant toner simply deteriorates. However, a balance control of the content can prevent the
deterioration. A content of a component having a molecular mass greater than
30,000 is from 1% to 10%, and preferably from 3% to 6%, although depending on

the toner material.
The number average molecular mass of the THF soluble component is
1,500 to 15,000. 1,500 or less results in difficulty of pigment dispersion and
control of making into particles during emulsion, causing a problem in wax
dispersibility, and more than 15,000 makes it difficult to form particles.
The shape and diameter distribution, based on the number, of the toner
of the second aspect of the invention can be measured, for example, by a flow
type particle image analyzer, FPIA-2100 by Sysmex Corporation. The
diameter distribution by a flow type particle image analyzer is more accurate
than that by Coulter method in the measurement of particle less than 2 µm.
The shape is represented by circularity. The circularity can be measured by
the method described later, the circularity is the value calculated by dividing the
circumference of an equivalent circle having the same projected area as the
projected area of toner particle by the circumference of actual toner particle.
Therefore, the circularity of perfect circle is 1.000. As the value becomes
smaller from 1, the shape tend to become spindle shaped (ellipse shaped).
The average circularity of the toner of the second aspect of the invention
is 0.900 to 0.960, and the toner preferably has spindle shape as shown in FIG. 22.
The toner having an average circularity less than 0.900 has irregular shape and
sufficient transferability or high quality images with no dust cannot be obtained.
Particles having irregular shape have many contact points with smooth media
such as a photoconductor, and charge concentrates on the top of projection at the

high points. Thus, particles having irregular shape have relatively stronger
van der Waals force and image force than spherical particles. Therefore, in the
case of toners where irregular particles and spherical particles are mixed, in an
electrostatic transfer step, spherical particles move selectively and resulted in
dropouts in letter images or line images. Moreover, the residue toner must be
removed for the next developing step, leading to the requirement for a cleaning
unit, or problems occur such as low toner yield (the rate of toner to be used in
image forming). The circularity of pulverized toner measured by this analyzer
is normally 0.910 to 0.920.
The average circularity can be measured in the same way as in the first
aspect.
The production method or material of the toner according to the first
and second aspects of the invention is not particularly limited as long as the
above-mentioned conditions are satisfied, and can be appropriately selected
according to the purpose. For example, the binder resin to be used is preferably
polyester resin in terms of fixing property at low temperatures.
Those prepared by the following way is suitable as the toner.
Specifically, toner material containing at least active hydrogen group containing
compounds and reactive polymers thereof is dissolved in an organic solvent to
prepare toner solution, then the toner solution is dispersed into an aqueous
medium to prepare dispersion, the active hydrogen group containing compounds
and reactive polymers thereof are allowed to react in the aqueous medium to

generate an adhesive base material in particle form, and the organic solvent is
removed to obtain toner.
The above-mentioned production method of polymerized toner has high
selectivity of resin and in the method, polyester resin having high fixing
property at low temperatures can be used. In addition, because of the excellent
ability to form particles and easily controlled particle diameter, particle size
distribution and shape, the toner produced by the above-mentioned production
method is preferable.
The toner material contains at least active hydrogen group containing
compounds and reactive polymers thereof, binder resin, releasing agent,
adhesive base material produced by reaction with colorant, and other element
such as resin fine particles, charge controlling agent, and the like as necessary.
-Adhesive base material-
The adhesive base material may exhibit adhesiveness with recording
medium such as paper and contain adhesive polymer produced from a reaction
between the active hydrogen group containing compounds and reactive
polymers thereof and may also contain binder resin selected from known binder
resins.
The average molecular mass (Mw) of adhesive base material is not
particularly limited and can be appropriately selected according to the purpose.
For example, it is preferably 1,000 and more, more preferably 2,000 to
10,000,000 and most preferably 3,000 to 1,000,000.

If the average molecular mass is less than 1,000, hot offset resistance
may be deteriorated.
The storage modulus of the adhesive base material is not particularly
limited and may be selected according to the purpose. For example, the
temperature TG', at which the storage modulus determined at 20Hz is
10.000dyne/cm2, is normally 100°C or more and preferably from 110°C to 200°C.
If the temperature TG' is less than 100°C, hot offset resistance may be
deteriorated.
The viscosity of adhesive base material is not particularly limited and
may be selected accordingly. For example, the temperature Tn, at which the
viscosity determined at 20Hz is 1,000 poises, is normally 180°C or less and
preferably from 90°C to 160°C. If the temperature (Tn) is more than 180°C,
fixing ability at low temperature may be deteriorated.
From the viewpoint of simultaneous pursuit of hot offset resistance and
fixing ability at low temperature, the temperature TG' is preferably higher than
the temperature Tn.. Specifically, the difference between TG' and Tn, TG' - Tn,
is preferably 0°C or more, and more preferably 10°C or more and most
preferably 20°C and more. The higher the difference, the better the effect will
be.
From the viewpoint of simultaneous pursuit of hot offset resistance and
fixing ability at low temperature, the difference between TG' and Tq is
preferably from 0°C to 100°C, more preferably from 10°C to 90°C and most

preferably from 20°C to 80°C.
Specific examples of adhesive base material are not particularly limited
and may be selected accordingly. Suitable examples thereof are polyester resin,
and the like.
The polyether resin is not particularly limited and may be selected
accordingly. Suitable examples thereof are ureα-modified polyester, and the
like.
The ureα-modified polyester is obtained by a reaction between amines
(B) as an active hydrogen group -containing compound, and isocyanate
group containing polyester prepolymer (A) as a polymer reactive with active
hydrogen group containing compound in the aqueous medium.
In addition, the ureα-modified polyester may include a urethane bond
as well as a urea bond. A molar ratio of the urea bond content to the
urethane bond content is preferably 100/0 to 10/90, more preferably 80/20 to
20/80, and most preferably 60/40 to 30/70.
If a molar ratio of the urea bond is less than 10%, hot-offset resistance
may be deteriorated.
Specific examples of the ureα-modified polyester are preferably the
following (1) to (10): (1) A mixture of (i) polycondensation product of
bisphenol A ethyleneoxide dimole adduct and isophthalic acid, and (ii)
ureα-modified polyester prepolymer which is obtained by reacting isophorone
diisocyanate with a polycondensation product of bisphenol A ethyleneoxide

dimole adduct and isophtalic acid, and modifying with isophorone diamine;
(2) A mixture of (iii) a polycondensation product of bisphenol A
ethyleneoxide dimole adduct and terephthalic acid, and (ii) ureα-modified
polyester prepolymer which is obtained by reacting isophorone diisocyanate
with a polycondensation product of bisphenol A ethyleneoxide dimole adduct
and terephthalic acid, and modifying with isophorone diamine; (3) A
mixture of (iv) polycondensation product of bisphenol A ethyleneoxide dimole
adduct, bisphenol A propyleneoxide dimole adduct and terephthalic acid, and
(v) ureα-modified polyester prepolymer which is obtained by reacting
isophorone diisocyanate with polycondensation product of bisphenol A
ethyleneoxide dimole adduct, bisphenol A propyleneoxide dimole adduct and
terephthalic acid, and modifying with isophorone diamine; (4) A mixture of
(vi) polycondensation product of bisphenol A propyleneoxide dimole adduct
and terephthalic acid, and (v) ureα-modified polyester prepolymer which is
obtained by reacting isophorone diisocyanate with polycondensation product
of bisphenol A ethyleneoxide dimole adduct, bisphenol A propyleneoxide
dimole adduct and terephthalic acid, and modifying with isophorone diamine;
(5) A mixture of (iii) polycondensation product of bisphenol A ethyleneoxide
dimole adduct and terephthalic acid, and (vii) ureα-modified polyester
prepolymer which is obtained by reacting isophorone diisocyanate with
polycondensation product of bisphenol A ethyleneoxide dimole adduct and
terephthalic acid, and modifying with hexamethylene diamine; (6) A

mixture of (iv) polycondensation product of bisphenol A ethyleneoxide dimole
adduct, a bisphenol A propyleneoxide dimole adduct and terephthalic acid,
and (vii) ureα-modified polyester prepolymer which is obtained by reacting
isophorone diisocyanate with polycondensation product of bisphenol A
ethyleneoxide dimole adduct and terephthalic acid, and modifying with
hexamethylene diamine; (7) A mixture of (iii) polycondensation product of
bisphenol A ethyleneoxide dimole adduct and terephthalic acid, and (viii)
ureα-modified polyester prepolymer which is obtained by reacting isophorone
diisocyanate with polycondensation product of bisphenol A ethyleneoxide
dimole adduct and terephthalic acid, and modifying with ethylene diamine;
(8) A mixture of (i) polycondensation product of bisphenol A ethyleneoxide
dimole adduct and isophthahc acid, and (ix) ureα-modified polyester
prepolymer which is obtained by reacting diphenylmethane diisocyanate with
polycondensation product of bisphenol A ethyleneoxide dimole adduct and
isophthahc acid, and modifying with hexamethylene diamine; (9) A mixture
of (iv) polycondensation product of bisphenol A ethyleneoxide dimole adduct,
bisphenol A propyleneoxide dimole adduct, terephthalic acid and
dodecenylsuccinic anhydride, and (x) ureα-modified polyester prepolymer
which is obtained by reacting diphenylmethane diisocyanate with
polycondensation product of bisphenol A ethyleneoxide dimole adduct,
bisphenol A propyleneoxide dimole adduct, terephthalic acid and
dodecenylsuccinic anhydride, and modifying with hexamethylene diamine ;

(10) A mixture of (i) polycondensation product of bisphenol A ethyleneoxide
dimole adduct and isophthalic acid, and (xi) urea modified polyester
prepolymer which is obtained by reacting toluene diisocyanate with
polycondensation product of bisphenol A ethyleneoxide dimole adduct and
isophthalic acid, and modifying with hexamethylene diamine.
— Active Hydrogen Group containing Compound —
The active hydrogen group containing compound functions as an
elongation initiator or crosslinking agent at the time of elongation reactions
or crosslinking reactions with the polymer reactive with aforesaid compounds
in the aqueous medium.
The active hydrogen group containing compounds are not
particularly limited as long as containing active hydrogen group, and may be
selected accordingly. For example, if a polymer reactive with the active
hydrogen group containing compounds is an isocyanate group containing
polyester prepolymer (A), from the viewpoint of ability to increase molecular
mass by reactions such as elongation reaction, crosslinking reaction, or the
like, with the isocyanate group containing polyester prepolymer (A), amines
(B) may be suitably used.
Active hydrogen groups are not particularly limited and may be
selected accordingly. Examples include hydroxyl groups such as alcoholic
hydroxyl group and phenolic hydroxyl group, amino groups, carboxyl groups,
mercapto groups, and the like. These may be used alone or in combination.

Of these, alcoholic hydroxyl group is especially preferable.
The amines (B) are not particularly limited and may be selected
accordingly. Examples of amines (B) include diamine (B1), polyamine having 3
or more valence (B2), amino alcohol (B3), amino mercaptan (B4), amino acid
(B5), block compound in which the amino group of (Bl) to (B5) is blocked (B6),
and the like.
These may be used alone or in combination. Of these, diamine (Bl) and a
mixture of diamine (Bl) with a small amount of polyamine having 3 or more
valence (B2) are especially preferable.
Examples of diamine (Bl) include aromatic diamine, alicyclic diamine
and aliphatic diamine. Examples of aromatic diamine are phenylene diamine,
diethyltoluene diamine, 4,4'diaminophenylmethane, and the like. Examples
of alicyclic diamine are 4,4'-diammo_3,3'-dimethyldicycrohexylmethane, diamine
cyclohexane, isophorone diamine, and the like. Examples of aliphatic diamine
are ethylene diamine, tetramethylene diamine, hexamethylene diamine and the
like.
Examples of polyamine having 3 or more valence (B2) include
methylene triamine, triethylene tetramine, and the like.
Examples of amino alcohol (B3) include ethanolamine,
hydroxyethylaniline and the like.
Examples of amino mercaptan (B4) include aminoethylmercaptan,
aminopropylmercaptan, and the like.

Examples of amino acid (B5) include amino propionic acid, amino capric
acid, and the like.
Examples of block compound in which the amino group of (B1) to (B5) is
blocked (B6) include ketimine compound, oxazoline compound, and the like
obtained from amines of (Bl) to (B5) and ketones such as acetone,
methylethylketone, methylbutylketone and the like.
A reaction terminator may be used to stop elongation reaction,
crosslinking reaction, or the like between active hydrogen group containing
compound and polymers reactive with the compound. It is preferable to use
reaction terminator because it enables to control molecular mass of adhesive
base material within a preferable range. Examples of reaction terminator
include monoamine such as diethylamine, dibutylamine, butylamine,
laurylamine, and the like, block compounds in which these monoamines are
blocked such as ketimine compound, or the like.
The mixture ratio of amines (B) and the isocyanate group containing
prepolymer (A), in terms of mixture equivalent ratio of isocyanate group [NCO]
in the isocyanate group containing prepolymer (A) and amino group [NHx] in
the amines (B), [NCO]/[NHx], is preferably from 1/3 to 3/1, more preferably from
1/2 to 2/1 and most preferably from 1/1.5 to 1.5/1.
When the mixture equivalent ratio [NCO]/[NHx] is less than 1/3, fixing
ability at low temperature may deteriorate, and when it is more than 3/1, the
molecular mass of ureα-modified polyester becomes low, possibly imparing hot

offset resistance.
- Polymer reactive with active hydrogen group containing compound -
The polymer reactive with active hydrogen group -containing compound
(hereinafter may be referred to as "prepolymer" is not particularly limited as
long as it contains at least a reactive site with active hydrogen group containing
compound and may be selected from known resins, etc. accordingly. Examples
of polymer reactive with active hydrogen group -containing compound include
polyol resin, polyacryl resin, polyester resin, epoxy resin, derivative resins
thereof, and the lite.
These may be used alone or in combination. Of these, from the view
point of having high flowability and transparency in the fusing process,
polyester resin is especially preferable.
A reactive site with active hydrogen group containing compounds of the
prepolymer is not particularly limited and may be selected from known
substituents accordingly. Examples of substituents include isocyanate group,
epoxy group, carboxylic acid, acid chloride group, and the like.
These may be used alone or in combination. Of these, isocyanate group
is especially preferable.
Among prepolymers, polyester resin containing urea bond formation
group (RMPE) is especially preferable, because it is easy to control the molecular
mass of polymer elements and has oilless fixing ability at low temperature, as
well as ability to sustain favorable releasing and fixing abilities even when it

lacks releasing oil coating system for the heating medium for fixation.
Examples of urea bond formation group include isocyanate group, and
the like. When the urea bond formation group of above-mentioned polyester
resin containing urea bond formation group (RMPE) is an isocyanate group,
isocyanate group containing polyester prepolymer (A) is especially preferable as
an polyester resin (KMPE).
The isocyanate group containing polyester prepolymer (A) is not
particularly limited and may be selected accordingly. Examples of isocyanate
group containing polyester prepolymer (A) include polycondensates of polyol
(PO) and polycarboxylic acid (PC), provided that they are also reactants of active
hydrogen group containing polyester resin and polyisocyanate (PIC).
The polyol (PO) is not particularly limited and may be selected
accordingly. Examples of polyol (PO) include diol (DIO), polyol having 3 or
more valence (TO), a mixture of diol (DIO) and polyol having 3 or more
valence (TO), and the like. These can be used alone or in combination. Of
these, diol (DIO) alone, a mixture of diol (DIO) and a small amount of polyol
having 3 or more valence (TO), or the like are preferable.
Examples of diol (DIO) include alkylene glycol, alkylene ether glycol,
alicyclic diol, alkylene oxide adducts of alicyclic diol, bisphenols, alkylene
oxide adducts of bisphenols, and the like.
The alkylene glycols of 2 to 12 carbon numbers are preferable and
examples include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol,

1,4-butanediol, and 1,6-hexanediol; alkylene ether glycols include diethylene
glycol, triethylene glycol, dipropylene glycol, polyethylene glycol,
polypropylene glycol, and polytetramethylene ether glycol; alicyclic diols such
as 1,4-cyclohexane dimethanol and hydrogenated bisphenol A; alkylene oxide
adducts of above-noted alicyclic diol such as ethylene oxide, propylene oxide,
and butylene oxide; bisphenols such as bispheonol A, bisphenol F, and
bisphenol S; and alkylene oxide adducts of the above-noted bisphenols such
as ethylene oxide, propylene oxide, and butylene oxide.
Among them, alkylene glycol having carbon number 2 to 12 and
alkylene oxide adducts of bisphenols are preferable, and alkylene oxide
adducts of bisphenols and a combination of alkylene oxide adducts of
bisphenols and alkylene glycol having carbon number 2 to 12 are particularly
preferable.
The polyol having 3 or more valence (TO) is preferably having
valency of 3 to 8, or more and examples thereof are polyaliphatic alcohol
having 3 or more valence, polyphenols having 3 or more valence, alkylene
oxide adducts of polyphenols having 3 or more valence, and the like.
Examples of polyol having 3 or more valence (TO) include
polyaliphatic alcohol having 3 or more valence such as glycerine, trimethylol
ethane, trimethylol propane, pentaerythritol, sorbitol, and the like.
Examples of polyphenols having 3 or more valence include trisphenol PA,
phenol novolac, cresol novolac, and like. The alkylene oxide adducts of

above-mentioned polyphenols having 3 or more valence include ethylene
oxide, propylene oxide, butylene oxide, and the like.
The mixing mass ratio, DIO:TO, of diol (DIO) and polyol having 3 or
more valence (TO) is preferably 100:0.01 to 10010 and more preferably 100:0.01
to 100:1.
Polycarboxilic acid (PC) is not particularly limited and may be selected
accordingly. Examples of polycarboxilic acid include dicarboxilic acid (DIC),
polycarboxilic acid having 3 or more valence (TC), a combination of dicarboxylic
acid (DIC) and polycarboxilic acid having 3 or more valence, and the like.
These may be used alone or in combination. Of these, dicarboxylic acid
(DIC) alone, or a combination of DIC and a small amount of polycarboxylic acid
having 3 or more valence (TC) are preferable.
Examples of dicarboxylic acid include alkylene dicarboxylic acid,
alkenylene dicarboxylic acid, aromatic dicarboxylic acid, and the like.
Examples of alkylene dicarboxylic acid include succinic acid, adipic acid,
sebacic acid, and the like. Alkenylene dicarboxylic acid is preferably with
carbon number 4 to 20 and examples thereof include maleic acid, fumar acid,
and the like. Aromatic dicarboxylic acid is preferably with carbon number 8 to
20 and examples thereof include phthalic acid, isophthalic acid, terephthalic
acid, naphthalendicarboxylic acid, and the like.
Of these, alkenylene dicarboxylic acid with carbon number 4 to 20 and
aromatic dicarboxylic acid with carbon number 8 to 20 are preferable.

The valency number of polycarboxylic acid (TO) with 3 or more valence
is preferably 3 to 8 or not less than the range and examples thereof include
aromatic polycarboxylic acid, and the like.
Aromatic polycarboxylic acid is preferably with carbon number 9 to 20
and examples thereof include trimellitic acid, pyromellitic acid, and the like.
The polycarboxylic acid (PC) may be an acid anhydride or a lower alkyl
ester of one selected from dicarboxylic acid (DIC), polycarboxylic acid having 3 or
more valence and a combination of dicarboxylic acid (DIC) and polycarboxylic
acid having 3 or more valence. Examples of lower alkyl ester include methyl
ester, ethyl ester, isopropyl ester, and the like.
The mixing mass ratio, DIC:TC, of dicarboxylic acid (DIC) and
polycarboxylic acid having 3 or more valence (TC) is not particularly limited and
may be selected accordingly, and it is preferably 100:0.01 to 100:10 and more
preferably 100:0.01 to 1001.
A mixing ratio of polyol (PO) and polycarboxylic acid (PC) at the time of
polycondensation reaction is not particularly limited and may be selected
accordingly. For example, the equivalent ratio, [OH] / [COOH], of hydroxyl
group [OH] of polyol (PO) and carboxyl group [COOH] of polycarboxilic acid (PC)
in general is preferably 2/1 to 1/1 and more preferably 1.5/1 to 1/1 and most
preferably 1.3/1 to 1.02/1.
The content of polyol (PO) in the isocyanate group containing polyester
prepolymer (A) is not particularly limited and may be adjusted accordingly, for

example, it is preferably 0.5% by mass to 40% by mass, more preferably 1% by
mass to 30% by mass and most preferably 2% by mass to 20% by mass.
If the content is less than 0.5% by mass, hot off-set resistance may be
deteriorated, making it difficult to pursue anti-heat preservability and fixing
property at low temperature at the same time. If the content is more than 40%
by mass, fixing property at low temperature may be deteriorated.
The polyisocyanate (PIC) is not particularly limited and may be selected
accordingly. Examples of polyisocyanate (PIC) include aliphatic polyisocyanate,
alicyclic polyisocyanate, aromatic diisocyanate, aromatic aliphatic diisocyanate,
isocyanurates, blocked-out ones thereof with phenol derivatives, oxime, capro
lactam, and the like.
Examples of aliphatic polyisocyanate include tetramethylene
diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanate methyl caproate,
octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene
diisocyanate, tetradecamethylene diisocyanate, torimethylhexane diisocyanate,
tetramethylhexane diisocyanate, and the like. Examples of alicyclic
polyisocyanate include isophorone diisocyanate, cyclohexylmethane diisocyanate,
and the like. Examples of aromatic diisocyanate include trilene diisocyanate,
diphenylmethane diisocyanate, 1,5-naphtylene diisocyanate, diphenylene-4,4'-
diisocyanate, 4,4'-diisocyanato-3,3'-dimethyldiphenyl,
3-methyldiphenylmethane-4,4'- diisocyanate, diphenylether4,4'- diisocyanate,
and the like. Examples of aromatic aliphatic diisocyanate include α,α,α',

a'-tetramethylxylylene diisocyanate, and the like. Examples of isocyanurates
include tris-isocyanatoalkyl-isocyanurate, triisocyanatocycloalkyl-isocyanurate,
and the like.
These may be used alone or in combination.
Generally, the equivalent mixing ratio, [NCO] / [OH], of isocyanate
group [NCO] of polyisocyanate (PIC) to hydroxyl group [OH] of active hydrogen
group containing polyester resin such as hydroxyl group containing polyester
resin at the time of reaction, is preferably 5/1 to 1/1, more preferably 4/1 to 1.2/1
and most preferably 3/1 to 1.5/1.
If the value of isocyanate group [NCO] is more than 5, fixing property at
low temperature may be deteriorated, and if it is less than 1, off-set resistance
may be deteriorated.
The content of polyisocyanate (PIC) in the isocyanate group containing
polyester prepolymer (A) is not particularly limited and may be adjusted
accordingly. It is preferably 0.5% by mass to 40% by mass, more preferably 1%
by mass to 30% by mass and most preferably 2% by mass to 20% by mass.
If the content is less than 0.5% by mass, hot off-set resistance may be
deteriorated, making it difficult to pursue anti-heat preservability and fixing
property at low temperature simultaneously and if it is more than 40% by mass,
fixing property at low temperature may be deteriorated.
The average quantity of isocyanate group contained within one
molecule of the isocyanate group containing polyester prepolymer (A) is

preferably 1 or more, more preferably 1.2 to 5 and most preferably 1.5 to 4.
If the average quantity of isocyanate group is less than 1, molecular
mass of polyester resin (RMPE) modified with urea bond formation group
becomes low and hot off-set resistance may be deteriorated.
The average molecular mass (Mw) of the polymer reactive with active
hydrogen group containing compound, in terms of molecular mass distribution
by gel permeation chromatography (GPC) of tetrahydrofuran (THF) soluble
component, is preferably 1,000 to 30,000 and more preferably 1,500 to 15,000.
If the average molecular mass (Mw) is less than 1,000, anti heat preservability
may be deteriorated and if it is more than 30,000, fixing property at low
temperature may be deteriorated.
The measurement of molecular mass distribution by gel permeation
chromatography (GPC), for example, may be performed as follow.
First, the column inside the heat chamber of 40°C is stabilized. At this
temperature, tetrahydrofuran (THF) as a column solvent is drained at a current
speed of 1ml/minute and 50µl to 200µl of tetrahydrofuran sample fluid of the
resin whereof a sample density is adjusted to 0.05% by mass to 0.6% by mass, is
poured and measured. In the measurement of molecular mass of the sample, a
molecular mass distribution of the sample is calculated from the relationship
between log values of the analytical curve made from several monodisperse
polystyrene standard samples and counted numbers. The standard
polystyrene sample for making analytical curves is preferably the one with a

molecular mass of 6x102,2-lx102, 4x102,1.75X104, l.1x105, 3.9x105, 8.6x105,
2x106 and 4.48x106 by Pressure Chemical Co. or Toyo Soda Manufacturing Co.,
Ltd. and at least using approximately 10 pieces of the standard polystyrene
sample is preferable. A refractive index (RI) detector may be used for
above-mentioned detector.
--Binder resin-
The binder resin is not particularly limited and may be selected
accordingly. Examples thereof are polyester resin, and the like and unmodified
polyester resin, that is a polyester resin not being modified, is especially
preferable.
Containing unmodified polyester resin in a toner can improve fixing
property at low temperature and glossiness.
Examples of unmodified polyester resin include the one similar to urea
bond formation group containing polyester resin such as polycondensation of
polyol (PO) and polycarboxylic acid (PC), and the like. The unmodified
polyester resin of which a part is compatible with the urea bond formation
group containing polyester resin (RMPE), that is, having similar structures that
are compatible to each other, is preferable in terms of fixing property at low
temperature and hot off-set resistance.
The average molecular mass (Mw) of unmodified polyester resin, in
terms of the molecular mass distribution by GPC (Gel permeation
chromatography) of tetrahydrofuran (THF) soluble component, is preferably

1,000 to 30,000 and more preferably 1,500 to 15,000. The content of the
component of which the average molecular mass (Mw) is less than 1,000, should
be 8% by mass to 28% by mass in order to prevent deterioration of anti heat
preservability. If the average molecular mass (Mw) is more than 30,000, fixing
property at low temperature may be deteriorated.
The glass transition temperature of the unmodified polyester resin is
generally 30°C to 70°C, preferably 35°C to 70°C, more preferably 35°C to 50°C
and most preferably 35°C to 45°C. If the glass transition temperature is less
than 30°C, anti-heat preservability of the toner may be deteriorated and if it is
more than 70°C, fixing property at low temperature may be insufficient.
The hydroxyl value of unmodified polyester resin is preferably 5
mgKOH/g or more, more preferably 10 mgKOH/g to 120 mgKOH/g and most
preferably 20 mgKOH/g to 80 mgKOH/g. If the hydroxyl value is less than 5
mgKOH/g, it is difficult to pursue anti-heat preservability and fixing property at
low temperature simultaneously.
The acid value of unmodified polyester resin is preferably 1.0 mgKOH/g
to 50.0 mgKOH/g, more preferably 1.0 mgKOH/g to 45.0 mgKOH/g and most
preferably 15.0 mgKOH/g to 45.0 mgKOH/g. In general, a toner tends to
become electrically negative by having acid values.
When unmodified polyester resin is contained in a toner, the mixing
mass ratio, RMPE / PE, of urea bond formation group containing polyester resin
(RMPE) to unmodified polyester resin (PE) is preferably 5/95 to 25/75 and more

preferably 10/90 to 25/75.
If the mixing mass ratio of unmodified polyester resin is more than 95,
hot off set resistance may be deteriorated, making it difficult to pursue anti-heat
preservability and fixing property at low temperature simultaneously, and if it is
less than 25, glossiness may be deteriorated.
The content of unmodified polyester resin in the binder resin, for
example, is preferably 50% by mass to 100% by mass, more preferably 70% by
mass to 95% by mass and most preferably 80% by mass to 90% by mass. If the
content is less than 50% by mass, fixing property at low temperature or
glossiness of the image may be deteriorated.
-Other Elements-
Other elements are not particularly limited and may be selected
accordingly. Examples thereof include colorants, releasing agents, charge
controlling agents, inorganic fine particles, flowability improvers, cleaning
ability improvers, magnetic materials, metal soaps, and the like.
The colorants are not particularly limited and may be selected from
known dyes and pigments accordingly. Examples thereof include carbon black,
nigrosine dyes, iron black, Naphthol Yellow S, Hansa Yellow (10G, 5G, G),
cadmium yellow, yellow iron oxide, yellow ocher, chrome yellow, Titan Yellow,
Polyazo Yellow, Oil Yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L,
Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G,
R), Tartrazine Lake, Quinoline Yellow Lake, anthracene yellow BGL,

isoindolinone yellow, colcothar, red lead oxide, lead red, cadmium red, cadmium
mercury red, antimony red, Permanent Red 4R, Para Red, Fire Red,
parachlororthonitroaniline red, Lithol Fast Scarlet G, Brilliant Fast Scarlet,
Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast
Scarlet VD, Vulcan Fast Rubine B, Brilliant Scarlet G, lithol Rubine GX,
Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B,
Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux
10B, BON Maroon Light, BON Maroon Medium, eosine lake, Rhodamine Lake
B, Rhodamine Lake Y, Alizarine Lake, Thioindigo Red B, Thioindigo Maroon,
Oil Red, quinacridone red, Pyrazolone Red, Polyazo Red, Chrome Vermilion,
Benzidine Orange, Perynone Orange, Oil Orange, cobalt blue, cerulean blue,
Alkali Blue Lake, Peacock Blue Lake, Victoria Blue Lake, metal-free
phthalocyanine blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue
(RS, BC), indigo, ultramarine, Prussian blue, Anthraquinone Blue, Fast Violet B,
Methyl Violet Lake, cobalt violet, manganese violet, dioxazine violet,
Anthraquinone Violet, chrome green, zinc green, chromium oxide, viridian,
emerald green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green
Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquinone Green,
titanium oxide, zinc white, and lithopone, and the like.
These may be used alone or in combination.
The content of the colorant in the toner is not particularly limited and
may be adjusted accordingly and it is preferably 1% by mass to 15% by mass

and more preferably 3% by mass to 10% by mass.
It the content is less than 1% by mass, tinctorial power of the colorant is
degraded, and if the content is more than 15% by mass, a dispersion failure of
pigments in the toner may occur, resulting in degradation of tinctorial power or
electric properties of the toner.
The colorant may be used as a master batch being combined with a
resin. Such resin is not particularly limited and may be selected from known
colorants accordingly. Examples thereof include polymers of styrene or
substituted styrenes, styrene copolymers, polymethyl methacrylates, polybuthyl
methacrylates, polyvinyl chlorides, polyvinyl acetates, polyethylenes,
polypropylenes, polyesters, epoxy resins, epoxy polyol resins, polyurethanes,
polyamides, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin,
terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum
resins, chlorinated paraffin, paraffin, and the like. These may be used alone or
in combination.
Examples of polymers of styrene or substituted styrenes include
polyester resin, polystyrene, poly p chlorostyrene, polyvinyl toluene, and the like.
Examples of styrene copolymers include styrene-p-chlorostyrene copolymer,
styrene-propylene copolymer, styrene-vinyltoluene copolymer,
styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer,
styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer,
styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer,

styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer,
styrene-methyl α-chloromethacrylate copolymer, styrene-acrylonitrile copolymer,
styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer,
styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer,
styrene-maleic acid copolymer, styrene-maleic ester copolymer, and the like.
The master batch can be obtained by mixing and kneading a resin for
master batch and the colorant with high shear force, To improve interaction
between colorant and resin, an organic solvent may be used. In addition, the
"flushing process" in which a wet cake containing colorant can be applied
directly, is preferable because it requires no drying. In the flushing process, a
water-based paste containing colorant and water is mixed and kneaded with the
resin and an organic solvent so that the colorant moves towards the resin, and
that water and the organic solvent are removed. The materials are
preferably mixed and kneaded using a triple roll mill and other high-shear
dispersing devices.
The releasing agent is not particularly limited and may be selected from
known agents accordingly and examples include waxes, and the like.
Examples of wax include carbonyl group containing wax, polyolefin wax,
long-chain hydrocarbon, and the like. These may be used alone or in
combination. Of these examples, carbonyl group containing wax is preferable.
Examples of carbonyl group containing wax include polyalkanoic acid
ester, polyalkanol ester, polyalkanoic acid amide, polyalkyl amide, dialkyl ketone,

and the like. Examples of polyalkanoic ester include carnauba wax, montan
wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate,
pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecandiol
distearate, and the like. Examples of polyalkanol ester include trimellitic
tristearate, distearyl maleate, and the like. Examples of polyalkanoic acid
amide include dibehenyl amide and the like. Examples of polyalkyl amide
include trimellitic acid tristearyl amide, and the like. Examples of dialkyl
ketone include distearyl ketone, and the like. Of these carbonyl
group-containing waxes, the polyalkanoic acid ester is particularly preferable.
Examples of polyolefin wax include polyethylene wax, polypropylene
wax, and the like.
Examples of long-chain hydrocarbon include paraffin wax, Sasol Wax,
and the like.
A melting point of the releasing agent is not particularly limited and
may be selected accordingly. It is preferably 40°C to 160°C, more preferably
50°C to 120°C, and most preferably 60°C to 90°C.
When the melting point is less than 40°C, the wax may adversely affect
anti-heat preservability. When the melting point is more than 160°C, it is
liable to cause cold offset at the time of fixing at low temperatures.
A melt viscosity of the releasing agent is preferably 5 cps to 1,000 cps,
and more preferably 10 cps to 100 cps by a measurement at a temperature of
20°C higher than the melting point of the wax.

If the melt viscosity is less than 5 cps, releasing ability may be
deteriorated. If the melt viscosity is more than 1,000 cps, on the other hand, it
may not improve offset resistance, and fixing property at low temperature.
The content of releasing agent in the toner is not particularly limited
and may be adjusted accordingly and it is preferably 0% by mass to 40% by
mass and more preferably 3% by mass to 30% by mass.
If the content is more than 40% by mass, flowability of the toner may be
deteriorated.
The charge controlling agent is not particularly limited, and may be
selected from known agents accordingly. The charge controlling agent is
preferably made of a material with color close to transparent and/or white
because colored materials may change color tone. Examples of charge
controlling agent include triphenylmethane dye, molybdic acid chelate
pigment, rhodamine dye, alkoxy amine, quaternary ammonium salt such as
fluoride modified quaternary ammonium salt, alkylamide, phosphoric simple
substance or compound thereof, tungsten simple substance or compound
thereof, fluoride activator, salicylic acid metallic salt, salicylic acid derivative
metallic salt, and the like. These may be used alone or in combination.
The charge controlling agent may be selected from the commercially
available products. Specific examples thereof include Bontron P-51 of a
quaternary ammonium salt, Bontron E-82 of an oxynaphthoic acid metal
complex, Bontron E-84 of a salicylic acid metal complrex and Bontron E-89 of

a phenol condensate by Orient Chemical Industries, Ltd.; TP-302 and TP-415
of a quaternary ammonium salt molybdenum metal complex by Hodogaya
Chemical Co.,' Copy charge PSY VP2038 of a quaternary ammonium salt,
Copy Blue PR of a triphenylmethane derivative and Copy charge NEG
VP2036 and Copy charge NX VP434 of a quaternary ammonium salt by
Hoechst Ltd.; LRA-901, and LR-147 of a boron metal complex by Japan Carlit
Co., Ltd.; quinacridone, azo pigment, and other high-molecular mass
compounds having functional group of sulfonic acid, carboxyl, quaternary
ammonium salt, or the like.
The charge controlling agent may be dissolved and/or dispersed in the
toner material after melt kneading with the master batch. The charge
controlling agent may also be added directly at the time of dissolving and
dispersing in the organic solvent together with the toner material. In
addition, the charge controlling agent may be added onto the surface of the
toner particles after toner particle production.
The content of the charge controlling agent in the toner depends on
the type of binder resin, presence or absence of external additives, and the
dispersion process selected to use and there is no defined prescription.
However, the content of charge controlling agent is preferably 0.1 part by
mass to 10 parts by mass and more preferably 0.2 part by mass to 5 part by
mass relative to 100 parts by mass of the binder resin, for example. When
the content is less than 0.1 parts by mass, charge may not be appropriately

controlled. If the content is more than 10 parts by mass, charge ability of
the toner becomes excessively large, which lessens the effect of charge
controlling agent itself and increases electrostatic attraction force with a
developing roller, leading to developer flowability or image density
degradation.
The inorganic fine particle is not particularly limited, and may be
selected from known inorganic fine particles accordingly. Specific examples of
inorganic fine particles include silica, alumina, titanium oxide, barium titanate,
magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide,
quartz sand, clay, mica, silicic pyroclastic rock, diatomaceous earth, chromic
oxide, cerium oxide, iron oxide red, antimony trioxide, magnesium oxide,
zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon
carbide and silicon nitride. Among them, silica and titanium dioxide are
especially preferable.
The primary particle diameter of the inorganic fine particle is preferably
5 nm to 2 µm, more preferably 5 nm to 500 nm. The specific surface are of the
inorganic fine particle by BET method is preferably 20 m2 / g to 500 m2 / g.
The content of the inorganic fine particle in the toner is preferably
0.01% by mass to 5.0% by mass, more preferably 0.01% by mass to 2.0% by
mass.
If these fluidizers are surface-treated to increase hydrophobicity,
degradation of flowability or charging ability can be prevented even under a

high humidified condition. Examples of suitable surface treatment agents
include silane coupling agents, silyl agents, silane coupling agents having
fluorinated alkyl group, organic titanate coupling agents, aluminium coupling
agents, silicone oils and modified silicone oils.
Examples of cleaning ability improver for removing residual developer
on the photoconductor or primary transferring medium after transferring
process include fatty acid metal salts such as zinc stearate, calcium stearate,
stearic acid, and the like; polymeric particles manufactured by soap-free
emulsion polymerization or the like such as polymethylmethacrylate particles,
polystyrene particles; and the like. The polymeric particles preferably have a
relatively narrow particle size distribution, and a volume average particle
diameter of 0.01 µm to 1 µm.
The magnetic material is not particularly limited, and may be selected
from known inorganic fine particles accordingly. Examples thereof include
iron powder, magnetite, ferrite, and the like. Among these, those with white
color are preferable in terms of color tone.
-Resin fine particles-
Preferably, the resin fine particles for use in the toner according to the
second aspect of the invention have a glass-transition temperature (Tg) of 50°C
to 70°C, and have an average molecular mass of 100,000 to 300,000.
When the glass-transition temperature is less than 50°C, blocking of
toner deteriorates, and when the glass-transition temperature is more than

70°C, softening of toner particle at the time of fixing is prevented.
The resin fine particles adhere to uppermost surface of toner particle
after emulsification, and thereby the toner particle has a toner structure which
prevents blocking of a low softening polymer inside the particle. Resin fine
particles may be spherical as 621 of FIG. 17, or may be irregular. In addition,
the resin fine particles may form layer so as to coat the toner surface due to the
influence of an organic solvent or subsequent processes for producing toner.
The resin fine particles according to the first and second aspects are
not particularly limited as long as they are capable of forming an aqueous
dispersion in an aqueous medium, and may be selected from known resins
accordingly. The resin fine particles may be formed of thermoplastic resin or
thermoset resin. Examples of resin fine particles include vinyl resin,
polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide
resin, silicone resin, phenol resin, melamine resin, urea resin, anilline resin,
ionomer resin, polycarbonate resin, and the like. Of these, vinyl resin is the
most preferable.
These may be used alone or in combination. Among these examples,
the resin fine particles formed of at least one selected from the vinyl resin,
polyurethane resin, epoxy resin, and polyester resin by which an aqueous
dispersion of fine spherical-shaped resin resin particles is easily obtained, are
preferable.
The vinyl resin is a polymer in which vinyl monomer is mono- or

solution thereof is dispersed in an aqueous medium in the presence of a
dispersing agent, and heated or added with a curing agent so as to be cured,
thereby obtaining the aqueous dispersion of the resin fine particles; (3) a
preparation method of aqueous dispersion of the resin fine particles in which, in
the case of the polyaddition and/or condensation resin such as polyester resin,
polyurethane resin, or epoxy resin, an arbitrary selected emulsifier is dissolved
in a precursor (monomer, oligomer or the like) or solvent solution thereof
(preferably being liquid, or being liquidized by heating), and then water is added
so as to induce phase inversion emulsification, thereby obtaining the aqueous
dispersion of the resin fine particles,' (4) a preparation method of aqueous
dispersion of the resin fine particles, in which a resin, previously prepared by
polymerization method which may be any of addition polymerization,
ring-opening polymerization, polyaddition, addition condensation, or
condensation polymerization, is pulverized by means of a pulverizing mill such
as mechanical rotation-type, jet-type or the like, and classified to obtain resin
fine particles, and then the resin fine particles are dispersed in an aqueous
medium in the presence of an arbitrary selected dispersing agent, thereby
obtaining the aqueous dispersion of the resin fine particles," (5) a preparation
method of aqueous dispersion of the resin fine particles, in which a resin,
previously prepared by a polymerization method which may be any of addition
polymerization, ring-opening polymerization, polyaddition, addition
condensation or condensation polymerization, is dissolved in a solvent, the

obtained resin solution is sprayed in the form of a mist to thereby obtain resin
fine particles, and then the obtained resin fine particles are dispersed in an
aqueous medium in the presence of an arbitrary selected dispersing agent,
thereby obtaining the aqueous dispersion of the resin fine particles; (6) a
preparation method of aqueous dispersion of the resin fine particles, in which a
resin, previously prepared by a polymerization method, which may be any of
addition polymerization, ring-opening polymerization, polyaddition, addition
condensation or condensation polymerization, is dissolved in a solvent, the
obtained resin solution is subjected to precipitation by adding a poor solvent or
cooling after heating and dissolving, the solvent is sequentially removed to
thereby obtain resin fine particles, and then the obtained resin fine particles are
dispersed in an aqueous medium in the presence of an arbitrary selected
dispersing agent, thereby obtaining the aqueous dispersion of the resin fine
particles; (7) a preparation method of aqueous dispersion of the resin fine
particles, in which a resin, previously prepared by a polymerization method,
which may be any of addition polymerization, ring-opening polymerization,
polyaddition, addition condensation or condensation polymerization, is dissolved
in a solvent to thereby obtain a resin solution, the resin solution is dispersed in
an aqueous medium in the presence of an arbitrary selected dispersing agent,
and then the solvent is removed by heating or reduced pressure to thereby
obtain the aqueous dispersion of the resin fine particles; (8) a preparation
method of aqueous dispersion of the resin fine particles, in which a resin,

previously prepared by a polymerization method, which is any of addition
polymerization, ring opening polymerization, polyaddition, addition
condensation or condensation polymerization, is dissolved in a solvent to thereby
obtain a resin solution, an arbitrary selected emulsifier is dissolved in the resin
solution, and then water is added to the resin solution so as to induce phase
inversion emulsification, thereby obtaining the aqueous dispersion of the resin
fine particles.
Examples of toner according to one of the first and second aspects of the
invention include a toner which is produced by known methods such as
suspension-polymerization method, emulsion-aggregation method,
emulsion-dispersion method, and the like. The toner is preferably produced
by dissolving the toner material containing an active hydrogen
group containing compound and a polymer reactive with the compound in an
organic solvent to prepare a toner solution, dispersing the toner solution in an
aqueous medium so as to form a dispersion, allowing the active hydrogen
group containing compound and the polymer reactive with the compound to
react so as to form an adhesive base material in the form of particles, and
removing the organic solvent.
-Toner Solution-
The toner solution is prepared by dissolving the toner material in an
organic solvent.
"Organic Solvent"

The organic solvent is not particularly limited and may be selected
accordingly, provided that the organic solvent allows the toner material to be
dissolved and/or dispersed therein. It is preferable that the organic solvent is a
volatile organic solvent having a boiling point of less than 150°C in terms of easy
removal from the solution or dispersion. Suitable examples thereof are toluene,
xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane,
1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene,
dichloroethylidene, methylacetate, ethylacetate, methyl ethyl ketone, methyl
isobutyl ketone, and the like. Among these solvents, toluene, xylene,
benzene, methylene chloride, 1,2-dichloroethane, chloroform, carbon
tetrachloride are preferable and furthermore, ethyl acetate is more preferable.
These solvents may be used alone or in combination.
The used amount of organic solvent is not limited and may be
adjusted accordingly. It is preferably 40 parts by mass to 300 parts by mass,
more preferably 60 parts by mass to 140 parts by mass and most preferably
80 parts by mass to 120 parts by mass with respect to 100 parts by mass of
the toner material.
-Dispersion
The dispersion is prepared by dispersing toner solution in an aqueous
medium.
When the toner solution is dispersed in an aqueous medium, a
dispersing element (oilspot) is formed in the aqueous medium.

-Aqueous Medium--
The aqueous medium is not particularly limited and may be selected
from known mediums such as water, watermiscible solvent, and a combination
thereof. Of these, water is particularly preferable.
The water-miscible solvent is not particularly limited, provided that it is
miscible with water, and examples thereof include alcohol, dimethylformamide,
tetrahydrofuran, Cellsolves, lower ketones, and the like.
Examples of alcohol include methanol, isopropanol, ethylene grycol, and
the like. Examples of lower ketones include acetone, methyl ethyl ketone, and
the like.
These may be used alone or in combination.
It is preferable to disperse the toner solution in the aqueous medium
while stirring.
The method for dispersion is not particularly limited and may be
selected from known dispersers such as low speed shear disperser,
high-speed-shear disperser, friction disperser, high-pressure-jet disperser,
supersonic disperser, and the like. Of these, high-speed-shear disperser is
preferable, because it is capable of controlling particle diameter of the dispersing
element (oilspot) to be within a range of 2 µm to 20 µm.
When the high-speed shear disperser is used, conditions like rotating
speed, dispersion time, dispersion temperature, and the like are not particularly
limited and may be adjusted accordingly. However, rotating speed is

preferably l,000rpm to 30,000rpm and more preferably 5,000rpm to 20,000rpm.
The dispersion time is preferably 0.1minute to 5 minutes for batch method.
The dispersion temperature is preferably 0°C to 150°C and more preferably
40°C to 98°C under pressure. Generally speaking, the dispersion is more
easily carried out at a high dispersing temperature.
An exemplary manufacturing process of the toner according to the first
and second aspects of the invention in which toner is manufactured by
producing adhesive base material in a form of particles is described below.
In the process in which toner is manufactured by producing adhesive
base material in a form of particles, a preparation of an aqueous medium phase,
a preparation of toner solution, a preparation of dispersion, an addition of
aqueous medium and other processes such as synthesis of active hydrogen
group -containing compound and reactive prepolymer thereof or synthesis of
active hydrogen group containing compound, and the like, for example.
The preparation of aqueous medium phase may be, for example, done
by dispersing resin fine particles in the aqueous medium. The amount of resin
fine particles added to the aqueous medium is not limited and may be adjusted
accordingly and it is preferably 0.5% by mass to 10% by mass, for example.
The preparation of toner solution may be done by dissolving and/or
dispersing toner materials such as active hydrogen group containing compound,
reactive polymer thereof, colorant, releasing agent, charge controlling agent and
unmodified polyester resin, and the like in the organic solvent.

These toner materials except reactive polymer (prepolymer) with active
hydrogen group containing compound may be added and blended in the
aqueous medium when resin fine particles are being dispersed in the aqueous
medium in the aqueous medium phase preparation, or they may be added into
the aqueous medium phase together with toner solution when toner solution is
being added into the aqueous medium phase.
The preparation of dispersion may be carried out by emulsifying
and/or dispersing the previously prepared toner solution in the previously
prepared aqueous medium phase. At the time of emulsifying and/or
dispersing, the active hydrogen group containing compound and the polymer
reactive with the compound are subjected to elongation and/or crosslinking
reaction, thereby forming the adhesive base material.
The adhesive base material (e.g. the aforementioned ureα-modified
polyester) is formed, for example, by (1) emulsifying and/or dispersing the
toner solution containing the polymer reactive with the compound (e.g.
isocyanate group containing polyester prepolymer (A)) in the aqueous
medium phase together with the active hydrogen group containing compound
(e.g. amines (B)) so as to form a dispersion, and then the active hydrogen
group containing compound and the polymer reactive with the compound are
subjected to elongation and/or crosslinking reaction in the aqueous medium
phase; (2) emulsifying and/or dispersing toner solution in the aqueous
medium previously added with the active hydrogen group containing

compound to form a dispersion, and then the active hydrogen
group containing compound and the polymer reactive with the compound are
subjected to elongation and/or crosslinking reaction in the aqueous medium
phase; (3) after adding and mixing toner solution in the aqueous medium, the
active hydrogen group containing compound is sequentially added thereto so
as to form a dispersion, and then the active hydrogen group containing
compound and the polymer reactive with the compound are subjected to
elongation and/or crosslinking reaction at an interface of dispersed particles
in the aqueous medium phase. In the process (3), it should be noted that
modified polyester resin is preferentially formed on the surface of
manufacturing toner particles, thus it is possible to generate concentration
gradient in the toner particles.
Condition of reaction for forming adhesive base material by
emulsifying and/or dispersing is not particularly limited and may be adjusted
accordingly with a combination of active hydrogen group containing
compound and the polymer reactive with the compound. A suitable reaction
time is preferably from 10 minutes to 40 hours and more preferably from 2
hours to 24 hours. A suitable reaction temperature is preferably from 0°C to
150°C and more preferably from 40°C to 98°C.
A suitable formation of the dispersion containing the polymer reactive
with active hydrogen group containing compound (e.g. the isocyanate
group containing polyester prepolymer (A)) in the aqueous medium phase is,

for example, a process in which the toner solution, produced from toner
materials such as the polymer reactive with the active hydrogen
group containing compound (e.g. the isocyanate group containing polyester
prepolymer (A)), colorant, releasing agent, charge controlling agent,
unmodified polyester, and the like that are dissolved and/or dispersed in the
organic solvent, is added in the aqueous medium phase and dispersed by
shear force. The detail of the dispersion process is as described above.
When preparing dispersion, a dispersing agent is preferably used in
order to stabilize the dispersing element (oil droplets formed from toner
solution) and sharpen the particle size distribution while obtaining a
predetermined shape of the dispersing element.
The dispersing agent is not particularly limited and may be selected
accordingly. Examples of dispersing agent include surfactant,
water-insoluble inorganic dispersing agent, polymeric protective colloid, and
the like. These may be used alone or in combination. Of these examples,
surfactant is most preferable.
Examples of surfactant include anionic surfactant, cationic surfactant,
nonionic surfactant, ampholytic surfactant, and the like.
Examples of anionic surfactant include alkylbenzene sulfonic acid
salts, α olefin sulfonic acid salts, phosphoric acid ester, and the like. Among
these, an anionic surfactant having fluoroalkyl group is preferable.
Examples of anionic surfactant having fluoroalkyl group include fluoroalkyl

carboxylic acid having 2 to 10 carbon atoms or metal salt thereof, disodium
perfluorooctanesulfonylglutamate, sodium- 3-{omegα-fluoroalkyl (Carbon
number 6 toll)oxy}-l-aIkyl (Carbon number 3 to 4) sulfonate,
sodium-3-{omega_fluoroalkanoyl(Carbon number 6 to 8)-N-ethylamino}
-1-propanesulfonate, fluoroalkyl(Carbon number 11 to 20) carboxylic acid or
metal salt thereof, perfluoroalkyl(Carbon number 7 to 13) carboxyhc acid or
metal salt thereof, perfluoroalkyK(Carbon number 4 to 12) sulfonic acid or
metal salt thereof, perfluorooctanesulfonic acid diethanol amide,
N-propyl-N-(2-hydroxyethyl)perfluorooctanesulfone amide, perfluoroalkyl
(Carbon number 6 to 10) sulfoneamidepropyltrimethylammonium salt,
perfluoroalkyl (Carbon number 6 to 10)-N-ethylsulfbnyl glycin salt,
monoperfluoroalkyl(Carbon number 6 to 16)ethylphosphate ester, and the
like. Examples of commercially available surfactant containing fluoroalkyl
group are: Surflon S-111, S112 and S-113 by Asahi Glass Co.; Frorard FC-93,
FC-95, FC-98 and FC-129 by Sumitomo 3M Ltd.; Unidyne DS-101 and
DS-102 by Daikin Industries, Ltd.; Megafac F-110, F-120, F-113, F-191, F-812
and F-833 by Dainippon Ink and Chemicals, Inc.; ECTOP EF-102, 103, 104,
105, 112,123A, 123B, 306A, 501, 201 and 204 by Tohchem Products Co.;
Futargent F-100 and F150 by Neos Co.
Examples of cationic surfactant include amine salt surfactant,
quaternary ammonium salt surfactant, and the like. Examples of amine
salt surfactant include alkyl amine salt, aminoalcohol fatty acid derivative,

polyamine fatty acid derivative, imidazoline, and the like. Examples of
quaternary ammonium salt surfactant include alkyltrimethyl ammonium
salt, dialkyldimethyl ammonium salt, alkyldimethyl benzyl ammonium salt,
pyridinium salt, alkyl isoquinolinium salt, benzethonium chloride, and the
like. Among these, preferable examples are primary, secondary or tertiary
aliphatic amine acid having fluoroalkyl group, aliphatic quaternary
ammonium salt such as perfluoroalkyl (Carbon number 6 to 10)
sulfoneamidepropyltrimethylammonium salt, benzalkonium salt,
benzetonium chloride, pyridinium salt, imidazolinium salt, and the like.
Specific examples of commercially available product thereof are Surflon S-121
by Asahi Glass Co., Frorard FC-135 by Sumitomo 3M Ltd., Unidyne DS-202
by Daikin Industries, Ltd., Megafack F 150 and F-824 by Dainippon Ink and
Chemicals, Inc., Ectop EF-132 by Tohchem Products Co., and Futargent
F-300 by Neos Co.
Examples of nonionic surfactant include fatty acid amide derivative,
polyhydric alcohol derivative, and the like.
Examples of ampholytic surfactant include alanine,
dodecyldi(aminoethyl)glycin, di(octylaminoethyl)glycin,
N-alkylN,N-dimethylammonium betaine, and the like.
Examples of water-insoluble inorganic dispersing agent include
tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica,
hydroxyl apatite, and the like.

Examples of polymeric protective colloid are acids, (meta)acrylic
monomers having hydroxyl group, vinyl alcohol or esters thereof, esters of
vinyl alcohol and compound having carboxyl group, amide compounds or
methylol compounds thereof, chlorides, monopolymers or copolymers having
nitrogen atom or heterocyclic rings thereof, polyoxyethylenes, celluloses, and
the like.
Examples of acids include acrylic acid, methacrylic acid,
α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid,
fumaric acid, maleic acid, maleic anhydride, and the like.
Examples of (meta) acrylic monomers having hydroxyl group include
B-hydroxyethylacrylate, B-hydroxyethylmethacrylate, 8-hydroxypropyl
acrylate, 8-hydroxypropyl methacrylate, Y-hydroxypropyl acrylate,
Y'hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate,
3-chloro-2-hydroxypropyl methacrylate, diethyleneglycol monoacrylic ester,
diethyleneglycol monomethacryhc ester, glycerin monoacryhc ester, glycerin
monomethacrylic ester, N-methylol acrylamido, N-methylolmethacrylamide,
and the like.
Examples of vinyl alcohol or ethers of vinyl alcohol include vinyl
methyl ether, vinyl ethyl ether, vinyl propyl ether, and the like.
Examples of ethers of vinyl alcohol and compound having carboxyl
group include vinyl acetate, vinyl propionate, vinyl butyrate, and the like.
Examples of amide compound or methylol compound thereof include

acryl amide, methacryl amide, diacetone acrylic amide acid, or methylol
thereof, and the like.
Examples of chlorides include acrylic chloride, methacrylic chloride,
and the like.
Examples of monopolymers or copolymers having nitrogen atom or
heterocyclic rings thereof include vinyl pyridine, vinyl pyrrolidone, vinyl
imidazole, ethylene imine, and the like.
Examples of polyoxyethylenes include polyoxyethylene,
polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine,
polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene
nonylphenylether, polyoxyethylene laurylphenylether, polyoxyethylene
stearylphenyl ester, polyoxyethylene nonylphenyl ester, and the like.
Examples of celluloses include methyl cellulose, hydroxyethyl
cellulose, hydroxypropyl cellulose, and the like.
In the preparation of dispersion, a dispersing stabilizer may be
employed as necessary. The dispersing stabilizer is, for example, acid-soluble
or alkali-soluble compound such as calcium phosphate, and the like.
When dispersing stabilizer is employed, calcium phosphate is dissolved
by acid such as hydrochloric acid, and then washed with water or decomposed
by enzyme, etc. to be removed from particles.
In the preparation of dispersion, a catalyst for the elongation and/or
crosslinking reaction may be employed as necessary. The catalyst is, for

example, dibutyltin laurate, dioctyltin laurate, and the like.
The organic solvent is removed from the obtained dispersion (emulsified
slurry). The removal of organic solvent is carried out, for example, by the
following methods; (1) the temperature of the dispersion is gradually increased,
and the organic solvent in the oil droplets is completely evaporated and
removed; (2) emulsified dispersion is sprayed in a dry atmosphere and the
water-insoluble organic solvent is completely evaporated and removed from the
oil droplets to form toner particles, while aqueous dispersing agent is evaporated
and removed simultaneously.
The circularity of the toner can be controlled by the strength of liquid
stirring before this removal of organic solvent and the time for removing the
solvent. When the removal of the solvent is slowly performed, the shape
becomes near to perfect sphere and the circularity increases to 0.980 or more.
When the stirring is performed vigorously and the removal of the solvent is
performed within a short period of time, the shape becomes uneven or irregular
and the circularity decreases to 0.900 to 0.960. When the emulsified liquid,
obtained after emulsification and dispersion in an aqueous medium, and further
by being subjected to an extension reaction, is stirred with a strong stirring force
at a temperature of 30°C to 50°C in a stirring tank during removal of the solvent,
it is possible to control the circularity in a range of 0.850 to 0.990. This is
considered to be attained by occurrence of volume shrinkage during formation of
particles due to abrupt removal of ethyl acetate contained therein, and the

shape can be controlled by stirring force and time. The time for removing the
solvent is within one hour. If the time is one hour or more, pigment begins to
aggregate, leading to the reduction of volume specific resistance.
The emulsified dispersion is sprayed in a dry atmosphere and the
water insoluble organic solvent is completely evaporated and removed from the
oil droplets to form toner particles, and simultaneously, aqueous dispersing
agent can also be evaporated and removed. Generally, the dry atmosphere into
which the dispersion is sprayed may be a heated gas, such as air, nitrogen,
carbon dioxide or combustion gas, particularly, a gas flow heated above the
boiling point of the solvent having the highest boiling point of the solvents used.
A short-time treatment with a spray drier, a belt drier or a rotary kiln can
provide toner particles with intended quality.
When the particle size distribution during emulsification and dispersion
is wide and washing and dry treatment is carried out keeping the particle size
distribution, the particle size distribution can be adjusted by classifying into
desired particle size distribution.
Once organic solvent is removed, toner particles are formed. The toner
particles are then preceded with washing, drying, and the like. And then toner
particles may be classified as necessary. The classification is, for example,
carried out by cyclone, decanter, or centrifugal separation thereby removing
particles in the solution. Alternatively, the classification may be carried out
after toner particles are obtained as powder by drying.

The obtained toner particles are subjected to mixing with particles such
as colorant, releasing agent, charge controlling agent, etc., and mechanical
impact, thereby preventing particles such as releasing agent felling off from the
surface of the toner particles.
Examples of the method for imparting mechanical impact include a
method in which an impact is imparted by rotating a blade at high speed, and a
method in which an impact is imparted by introducing the mixed particles into a
highspeed flow and accelerating the speed of the flow so as to make the
particles to clash with each other or to make the composite particles to clash
with an impact board. Examples of device employed for such method are
angmill by Hosokawa Micron Corporation, modified I-type mill by Nippon
Pneumatic Mfg. Co., Ltd. to decrease crushing air pressure, hybridization
system by Nara Machinery Co., Ltd., kryptron system by Kawasaki Heavy
Industries, Ltd., automatic mortar, and the like.
The coloration of the toner according to one of the first and second
aspects of the invention is not particularly limited and may be selected
accordingly. For example, the coloration is at least one selected from black
toner, cyan toner, magenta toner and yellow toner. Each color toner is obtained
by appropriately selecting the colorant to be contained therein. It is preferably
a color toner.
(Developer)
The developer of the invention at least contains the toner according to

one of the first and second aspects of the invention and further contains other
appropriately selected components such as the aforementioned carrier. The
developer can be either one component developer or two-component developer.
However, the two-component developer is preferable in terms of improved life
span when the developer is used, for example, in a high-speed printer that
corresponds to the improvement of recent information processing speed.
The one-component developer using the toner of the invention exhibits
less fluctuation in the toner particle diameter after toner inflow/outflow, and the
toner filming to the developing roller or the fusion of toner onto the members
such as blades for reducing toner layer thickness are absent, therefore providing
excellent and stable developing property and images over long-term use
(stirring) of the developing unit. The two-component developer using toner of
the invention exhibits less fluctuation in the toner particle diameter after toner
inflow/outflow for prolonged periods, and the excellent and stable developing
property can be obtained after stirring in a developing unit for prolonged
periods.
The carrier is not particularly limited and may be selected accordingly.
It is preferably the one having a core material and a resin layer coating the core
material.
The core material is not particularly limited and may be selected from
known materials. For example, 50 emu/g to 90 emu/g of manganese, strontium
(Mn, Sr) materials, manganese, magnesium (Mn, Mg) materials, and the like

are preferred. Highly magnetizable materials such as iron powder (100 emu/g
or more), magnetite (75 emu/g to 120 emu/g), and the like are preferred in terms
of ensuring appropriate image density. Weak magnetizable materials such as
copper — zinc (Cu - Zn) materials (30 emu/g to 80 emu/g) are preferred in terms
of reducing the impact on photoconductor where toner is forming a magnetic
brush, therefore advantageous for improving image quality. These may be
used alone or in combination.
The average particle diameter (volume average particle diameter (D50))
of the core material is preferably 10 µm to 200 µm and more preferably 40 µm to
100 µm.
When the average particle diameter (volume average particle diameter
(D50)) is less than 10 µm, the amount of fine powder in the carrier particle size
distribution increases whereas magnetization per particle decreases resulting in
the carrier scattering. When the average particle diameter is more than 150
µm, toner scattering may be caused due to the decrease of specific surface area.
Therefore, for a full-color image having many solid parts, reproduction of the
solid parts in particular may be insufficient.
The resin material is not particularly limited and may be selected from
known resins accordingly. Examples of resin material include amino resin,
polyvinyl resin, polystyrene resin, halogenated olefin resin, polyester resin,
polycarbonate resin, polyethylene resin, polyvinyl fluoride resin, polyvinylidene
fluoride resin, polytrifluoroethylene resin, polyhexafluoropropylene resin,

copolymers of vinylidene fluoride and acryl monomer, copolymers of vinylidene
fluoride and vinyl fluoride, fluoroterpolymer such as terpolymer of
tetrafiuoroethylene, vinylidene fluoride and non-fluoride monomer, silicone resin,
and the like. These may be used alone or in combination.
Examples of amino resin include ureα-formaldehyde resin, melamine
resin, benzoguanamine resin, urea resin, polyamide resin, epoxy resin, and the
like. Examples of polyvinyl resin include acryl resin, polymethylmetacrylate
resin, polyacrylonitrile resin, polyvinyl acetate resin, polyvinyl alcohol resin,
polyvinyl butyral resin, and the like. Examples of polystyrene resin include
polystyrene resin, styrene acryl copolymer resin, and the like. Examples of
halogenated olefin resin include polyvinyl chloride, and the like. Examples of
polyester resin include polyethyleneterephtalate resin and
polybutyleneterephtalate resin, and the like.
The resin layer may contain, for example, conductive powder, etc. as
necessary. Examples of conductive powder include metal powder, carbon black,
titanium oxide, tin oxide, zinc oxide, and the like. The average particle
diameter of conductive powder is preferably lum or less. When the average
particle diameter is more than 1µm, controlling electrical resistance may be
difficult.
The resin layer may be formed by, for example, dissolving silicone resin,
etc. in a solvent to prepare a coating solution, uniformly applying the coating
solution to the surface of core material by known method, drying, and baking.

Examples of application method include immersion, spray, and brushing, etc.
The solvent is not particularly limited and may be selected accordingly.
Examples of solvent include toluene, xylene, methyethylketone,
methylisobutylketone, cerusolbutylacetate, and the like.
The baking is not particularly limited and may be done by external
heating or internal heating. Examples of baking method include the one using
fixed electric furnace, flowing electric furnace, rotary electric furnace, burner or
microwave.
The content of resin layer in the carrier is preferably 0.01% by mass to
5.0% by mass. When it is less than 0.01% by mass, the resin layer may not be
formed uniformly on the surface of the core material. When it is more than
5.0% by mass, the resin layer may become excessively thick causing granulation
between carriers, and the uniform carrier particles may not be obtained.
When developer is a two-component developer, the content of the carrier
in the two-component developer is not particularly limited and may be selected
accordingly. For example, the content is preferably 90% by mass to 98% by
mass and more preferably 93% by mass to 97% by mass.
The mixing ratio of toner to carrier of the two-component developer is
1part by mass to 10.0 parts by mass of toner relative to 100 parts by mass of
carrier, in general.
The developer of the invention contains the toner according to one of the
first and second aspects of the invention and has excellent offset resistance and

co-polymerized. Examples of vinyl resin include styrene-(meth)acrylic acid
ester resin, styrene-butadiene copolymer, (meth)acrylic acid-acrylic acid ester
copolymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer,
styrene-(meth)acrylic acid copolymer, and the like.
Moreover, the resin fine particles may be formed of copolymer
containing a monomer having at least two or more unsaturated groups.
The monomer having at least two or more unsaturated groups is not
particularly limited and may be selected accordingly. Examples of such
monomer include sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (Eleminol RS-30 by Sanyo Chemical Industries Co.),
divinylbenzene, l,6hexanediol acrylate, and the like.
The resin fine particles are formed by polymerization performed by the
method appropriately selected from known methods. The resin fine particles
are preferably obtained in a form of aqueous dispersion of the resin fine particles.
Examples of preparation method of such aqueous dispersion include (1) a direct
preparation method of aqueous dispersion of the resin fine particles in which, in
the case of the vinyl resin, a vinyl monomer as a raw material is polymerized by
suspension-polymerization method, emulsification-polymerization method, seed
polymerization method or dispersion-polymerization method; (2) a preparation
method of aqueous dispersion of the resin fine particles in which, in the case of
the polyaddition and/or condensation resin such as polyester resin, polyurethane
resin, or epoxy resin, a precursor (monomer, oligomer or the like) or solvent

anti-heat preservability, therefore it is capable of forming excellent, clear and
high-quality images constantly.
The developer of the invention may be suitably used in forming images
by various electrophotographic methods known such as magnetic
one-component developing, non-magnetic one-component developing,
two-component developing, and the like. In particular, the developer of the
invention may be suitably used in the toner container, process cartridge, image
forming apparatus, and image forming method of the invention as described
below.
(Toner container)
The toner container of the invention comprises a container; and the
toner according to one of the first and second aspects of the invention and/or the
developer of the invention contained therein.
The container is not particularly limited and may be selected from
known containers. Preferable examples of the container include one having a
toner container body and a cap.
The toner container body is not particularly limited in size, shape,
structure or material and may be selected accordingly. The shape is preferably
a cylinder. It is particularly preferable that a spiral ridge is formed on the
inner surface and the contained toner is movable toward discharging end when
rotated and the spiral part, whether partly or entirely, serves as bellows.
The material of the toner container body is not particularly limited and

preferably being dimensionally accurate. For example, resins are preferable.
Among resins, polyester resin, polyethylene resin, polypropylene resin,
polystyrene resin, polyvinyl chloride resin, polyacrylic acid, polycarbonate resin,
ABS resin, polyacetal resin, and the like are preferable.
The toner container of the invention is easy to preserve and ship and is
handy. It is suitably used by being detachably mounted on the process
cartridge, image forming apparatus, and the like which are described later, for
supplying toner.
(Process cartridge)
The process cartridge of the invention at least comprises a latent
electrostatic image bearing member for bearing a latent electrostatic image and
a developing unit for developing the latent electrostatic image on the latent
electrostatic image bearing member using developer and further comprises
charging unit, exposing unit, developing unit, transferring unit, cleaning unit,
discharging unit and other units selected accordingly.
The developing unit at least contains a developer container for storing
the toner and/or developer of the invention and a developer carrier for carrying
and transferring the toner and/or developer stored in the developer container
and may further contain a layer thickness control member for controlling the
thickness of carried toner layer.
The process cartridge of the invention may be detachably mounted on a
variety of electrophotographic apparatuses, facsimile and printers and is

preferably detachably mounted on the electrophotographic apparatus of the
invention, which is described later.
The process cartridge comprises, for example as shown in FIG. 1,
photoconductor 102, charging unit 103, developing unit 104, and cleaning unit
105 and, 101 represents an entire process cartridge.
In this process cartridge, plural constituent elements, among
constituent elements such as a photoconductor, developing unit, charging unit,
cleaning unit, etc., may be constructed as the process cartridge and this process
cartridge is placed onto the main body of image forming apparatus such as a
copier and printer as detachable.
FIG. 21 shows an example of the process cartridge using a
two-component developer of the invention and has the same configuration and
effects as those of the process cartridge shown in FIG. 1. The symbols used in
FIG. 21 correspond to the symbols used in FIG. 1.
In the image forming apparatus comprising the process cartridge of the
invention, the photoconductor is rotationally driven at a predetermined
circumferential speed. The photoconductor receives uniform charge of positive
or negative predetermined potential from a charging unit in the roating process,
then is exposed to image exposure light from an image exposing unit such as a
slit exposure and laser beam, and thus latent electrostatic images are
sequentially formed on the surface of the photoconductor. Thus formed latent
electrostatic images are developed by toner with a developing unit, developed

toner images are sequentially transferred on a transfer material by a
transferring unit, which is fed from a paper feeding part between the
photoconductor and a transferring unit so as to match the rotation of the
photoconductor. The transfer material having transferred images is separated
from the surface of the photoconductor, introduced to an image fixing unit, and
images are fixed, and printed out as a copy to the outside of the apparatus.
The surface of the photoconductor after image transfer is cleaned as a result of
removal of residue toner remaining after transfer, further discharged, and then
is used for image forming repeatedly
(Image Forming Apparatus and Image Forming Method)
The image forming apparatus of the invention contains photoconductor,
latent electrostatic image forming unit, developing unit, transferring unit, fixing
unit and other units such as discharging unit, cleaning unit, recycling unit and
control unit as necessary.
The image forming method of the invention include latent electrostatic
image forming, developing, transferring, fixing and other steps such as
discharging, cleaning, recycling, controlling, etc. as necessary.
The image forming method of the invention may be favorably
implemented by the image forming apparatus of the invention. The latent
electrostatic image forming may be performed by the latent electrostatic image
forming unit, the developing may be performed by the developing unit, the
transferring may be performed by the transferring unit, and the fixing may be

performed by the fixing unit. And other steps may be performed by other units
respectively.
-Latent Electrostatic Image Forming and Latent Electrostatic Image Forming
Unit-
The latent electrostatic image forming is a step that forms a latent
electrostatic image on the photoconductor.
Materials, shapes, structures or sizes, etc. of the latent electrostatic
image bearing member (may be referred to as "photoconductive insulator",
"photoconductor") are not limited and may be selected accordingly and it is
preferably drum-shaped. The materials thereof are, for example, inorganic
photoconductors such as amorphous silicon, selenium; organic photoconductors
such as polysilane, phthalopolymethine, and the like. Of these examples,
amorphous silicon is preferred for its longer operating life.
For the amorphous silicon photoconductor, a photoconductor, (hereafter
may be referred to as "α-Si series photoconductor") having a photo-conductive
layer made of a_Si that is formed on the support by coating method such as
vacuum deposition, sputtering, ion-plating, thermo-CVD, photo-CVD,
plasma-CVD, and the like, while support is being heated at 50°C to 400°C, may
be used. Of these coating methods, plasma-CVD, whereby a_Si cumulolayer is
formed on the support by decomposition of the material gas by direct current,
high-frequency wave or microwave glow discharge, is preferable.
Examples of the layer structure of the amorphous silicon

photoconductor are as follows. FIGS. 9 through 12 are schematic diagrams for
explaining the layer structure of the photoconductor.
With reference to FIG. 9, a photoconductor for electrophotography 500
comprises a support 501 and a photoconductive layer 502 thereon. The
photoconductive layer 502 is formed of α-Si:H, X, and exhibits photoconductivity.
With reference to FIG. 10, a photoconductor for electrophotography 500
comprises a support 501, a photoconductive layer 502 and an amorphous silicon
surface layer 503 arranged on the support 501. The photoconductive layer 502
is formed of α-Si:H, X, and exhibits photoconductivity.
With reference to FIG. 11, a photoconductor for electrophotography 500
comprises a support 501, and on the support 501, a photoconductive layer 502,
an amorphous silicon surface layer 503 and an amorphous silicon charge
injection inhibiting layer 504. The photoconductive layer 502 is formed of
a-Si:H, X, and exhibits photoconductivity.
With reference to FIG. 12, a photoconductor for electrophotography 500
comprises a support 501 and a photoconductive layer 502 thereon. The
photoconductive layer 502 includes a charge generating layer 505 formed of
a-Si:H, X and a charge transport layer 506. An amorphous silicon surface layer
503 is arranged on the photoconductive layer 502.
The support of the photoconductor may be conductive or electrically
insulating. Examples of the conductive support include metals such as Al, Cr,
Mo, Au, In, Nb, Te, V, Ti, Pt, Pd, and Fe, or alloys thereof e.g. stainless steel.

The support may also be an electrically insulating support of a film or sheet of
synthetic resin such as polyester, polyethylene, polycarbonate, cellulose acetate,
polypropylene, polyvinyl chloride, polystyrene, and polyamide, or of glass,
ceramic, or the like, wherein at least a surface on the photosensitive layer
formed side of the electrically insulating support is treated to have conductivity.
The shape of the support may be a cylinder, plate, or endless belt having
a smooth or uneven surface, its thickness may be determined appropriately so
that a desired photoconductor for image forming apparatus can be formed;
however, when bendability as a photoconductor for image forming apparatus is
required, the thickness can be made as thin as possible as the function of the
support can be well exhibited. However, the support is normally required to be
10 µm or more in thickness from the points of production and handling,
mechanical strength, etc.
In the amorphous photoconductor, it is effective to dispose a charge
injection inhibiting layer between the conductive support and the
photoconductive layer according to necessity (See, FIG. 11). The charge
injection inhibiting layer inhibits a charge injection from the conductive support.
The charge injection inhibiting layer has a dependency on the polarity.
Specifically, when charges of a certain polarity are applied to a free surface of the
photoconductor, the charge injection inhibiting layer inhibits a charge from
being injected into the photosensitive layer from the support. However, the
charge injection inhibiting layer does not when charges of the opposite polarity

are applied, i.e., the charge injection inhibiting layer has a dependency on the
polarity. In order to attain such function, the charge injection inhibiting layer
contains relatively larger amounts of atoms controlling conductivity, compared
with the photoconductive layer.
The thickness of the charge injection inhibiting layer is preferably 0.1
µm to 5 µm, more preferably 0.3 µm to 4 µm, and most preferably 0.5 µm to 3 µm
for desired electrophotographic properties and better economical efficiency.
The photoconductive layer may be disposed on an undercoat layer
according to necessity. The thickness of the photoconductive layer 502 is
determined appropriately as desired in terms of electrophotographic properties
and better economical efficiency. The thickness is preferably 1 µm to 100 µm,
more preferably 20 µm to 50 µm, and most preferably preferably 23 µm to 45 µm.
When the photoconductive layer is constructed with plural layers to
separate its function, the charge transport layer mainly serves as a layer to
transport charge. The charge transport layer comprises at least a silicon atom,
carbon atom, and fluorine atom as its essential components, and optionally
comprises a hydrogen atom and oxygen atom so that the charge transport layer
is formed of a-SiC(H,F,0). Such charge transport layer exhibits desirable
photoconductivity, especially charge holding property, charge generating
property, and charge transporting property. In the invention, it is particularly
preferable that the charge transport layer comprises an oxygen atom.

The thickness of the charge transport layer is determined appropriately
as desired in terms of electrophotographic properties and better economical
efficiency. The thickness thereof is preferably 5 µm to 50 |im, more preferably
10 µm to 40 µm, and most preferably 20 µm to 30 1 µm.
When the photoconductive layer is constructed with plural layers to
separate its function, the charge generating layer mainly serves as a layer to
generate charge. The charge generating layer comprises at least a silicon atom
as its essential component does not substantially comprise a carbon atom, and
optionally comprises a hydrogen atom so that the charge generating layer is
formed of α-Si:H. Such charge generating layer exhibits desirable
photoconductivity, especially charge generating property and charge
transporting property.
The thickness of the charge generating layer is determined
appropriately as desired in terms of electrophotographic properties and better
economical efficiency. The thickness thereof is preferably 0.5 µm to 15 µm,
more preferably 1 µm to 10 µm, and most preferably 1 µm to 5 µm.
The amorphous silicon photoconductor may further comprise a surface
layer disposed on the photoconductive layer on the support as mentioned above
according to necessity. The surface layer is preferably an amorphous silicon
layer. The surface layer has a free surface and is disposed to attain an object of
the invention mainly in moisture resistance, usability in continuous repeated
use, electric strength, stability in operating environment, and durability.

In general, the thickness of the surface layer is preferably 0.01 µm to 3
µm, more preferably 0.05 µm to 2 µm, and most preferably 0.1 µm to 1 µm. If
the thickness is less than about 0.01 µm, the surface layer may be lost during
the use of the photoconductor due to abrasion. If it is more than 3 µm,
electrophotographic properties may be impaired such as an increase of residual
potential.
The amorphous silicon photoconductor has a high surface hardness and
high sensitivity with light with long wavelength, such as semiconductor laser
light (770 nm to 800 nm). In addition, little deterioration is observed after
repeated use, and thus the amorphous silicon photoconductor is used as a
photoconductor for electrophotography, for example, in a high-speed copier or a
laser beam printer (LBP).
The latent electrostatic image may be formed, for example, by uniformly
charging the surface of photoconductor, and exposing it imagewise, and this may
be performed by the latent electrostatic image forming unit.
The latent electrostatic image forming unit, for example, contains a
charger which uniformly charges the surface of latent electrostatic image
bearing member, and an irradiator which exposes the surface of latent
electrostatic image bearing member imagewise.
Charging may be performed, for example, by applying a voltage to the
surface of latent electrostatic image bearing member using the charger.
The charger is not limited and may be selected accordingly. Examples

of charger include known contact chargers equipped with conductive or
semi-conductive roller, brush, film or rubber blade and non-contact chargers
using corona discharges such as corotron or scorotron, etc.
Here, FIG. 8 shows a schematic configuration of an example of the
image forming apparatus using a contact charger. A photoconductor 10 as a
member to be charged or image bearing member, is rotationally driven in the
arrow direction at a predetermined speed (process speed). A charging roller
152 as a charging member is brought into contact with this photosensitive drum
10 and comprises, as a basic configuration, a cored bar 521 and a conductive
rubber layer 522 formed on the outside circumferential surface of this cored bar
in the form of roller concentrically. The both terminals of the cored bar are
supported with e.g. bearings (not shown) so that the charging roller can rotate
freely, and the charging roller is pressed to the photosensitive drum at a
predetermined pressure by a pressurization unit (not shown). This charging
roller in this figure rotates along with the rotational driven of the photosensitive
drum. The charging roller is formed with a diameter of 16 mm in which a
cored bar having a diameter of 9 mm is coated with a rubber layer having a
moderate resistance of approximately 100,000 Ώcm.
A power supply 153 shown in the figure is electrically connected with
the cored bar 521 of the charging roller, and a predetermined bias is applied to
the charging roller by the power supply. Thus, the surface of the
photoconductor is uniformly charged at a predetermined polarity and potential.

The configuration of charging members may be of magnetic brush, fur
brush or any other configurations other than of the roller, and may be selected
according to the specification or configuration of the electrophotographic
apparatus. In the apparatus where magnetic brush is used, the magnetic
brush is constructed with various ferrite particles such as Zn-Cu ferrite that are
used as charging members, nonmagnetic conductive sleeve supporting the
charging member, and the magnet roll contained in the nonmagnetic conductive
sleeve. When a brush is used, for example, fur is made conductive by carbon,
copper sulfide, metal or metal oxide and it is winded around, or stuck to the
cored bar which has been made conductive by metal and others to use as a
charger.
The charger is not limited to above-mentioned contact chargers,
however, it is preferable to use contact chargers because of the ability to decrease
the ozone generated from charger in the image-forming apparatus.
Exposures may be performed by exposing the surface of photoconductor
imagewise using exposure machines, for example.
The exposure machine is not limited as long as it is capable of exposing
the surface of photoconductor that has been charged by a charger to form an
image as it is expected, and may be selected accordingly. Examples thereof
include various exposure machines such as copy optical system, rod lens array
system, laser optical system, and liquid crystal shutter optical system, etc.
A backlight system may be employed in the invention by which the

photoconductor is exposed imagewise from the rear surface.
- Developing and Developing Unit -
Developing is a step by which a latent electrostatic image is developed
using the toner according to one of the first and second aspects of the invention
and/or the developer to form a visible image.
The visible image may be formed, for example, by developing a latent
electrostatic image using toner and/or developer, which may be performed by a
developing unit.
The developing unit is not limited as long as it is capable of developing
an image by using the toner according to one of the first and second aspects of
the invention and/or developer, for example, and may be selected from known
developing unit accordingly. Suitable examples thereof include those having
developing units that contain the toner according to one of the first and second
aspects of the invention and/or developer that can supply toners to the latent
electrostatic images by contact or with no contact, developing units that contain
the toner container of the invention are more preferable.
The developing unit may be of dry developing system or wet developing
system and may also be for single or multiple colors. Preferred examples
include one having mixer whereby toner and/or developer is charged by
friction-stirring and rotatable magnet rollers.
In the developing unit, the toner and the carrier may, for example, be
mixed and stirred together. The toner is thereby charged by friction, and forms

a magnetic brush on the surface of the rotating magnet roller. Since the
magnet roller is arranged near the latent electrostatic image bearing member
(photoconductor), a part of the toner constructing the magnetic brush formed on
the surface of the magnet roller is moved toward the surface of the latent
electrostatic image bearing member (photoconductor) due to the force of
electrical attraction. As a result, a latent electrostatic image is developed by
the use of toner, and a visible toner image is formed on the surface of the
photoconductor.
In the developing unit, a vibration bias voltage formed of a
direct-current voltage overlapped with an alternating voltage is applied to a
developing sleeve from a power supply as a developing bias. Potentials of a
background and an image portions are positioned between a maximum value
and a minimum value of the vibration bias potential. Thus, an alternate
electric filed alternating its direction is formed in a developing section. In this
alternate electric filed, a toner and a carrier in the developer vibrate hard, and
the toner escapes from an electrostatic binding force to the developing sleeve
and/or carrier. Then, the toner soars to a photoconductive drum and adheres to
the photoconductive drum in accordance with a latent image thereon.
A difference between maximum and minimum values of the vibration
bias voltage (a Voltage between peaks) is preferably from 0.5 kV to 5 kV and a
frequency is preferably from 1 kHz to 10 kHz. Waveform of the vibration bias
voltage may be a rectangular wave, a sine wave, a triangular wave, or the like.

The direct-current voltage of the vibration bias is a value between the potentials
of the background and image as mentioned above, and the value is preferably
closer to the potential of the background than to that of the image to prevent
foggy images in a potential area of the background, or a toner adhesion.
When the vibration bias voltage has a rectangular waveform, it is
desirable that a duty ratio be not greater than 50%. Here, the duty ratio is a
time ratio while the toner goes for the photoconductor in a cycle of the vibration
bias. In this way, the difference between a peak value of the toner going for the
photoconductor and an average time of the bias can be large. Consequently, the
movement of the toner becomes further activated hence the toner is accurately
adheres to the potential distribution on a surface of a latent image, and surface
roughness and an image resolution can be improved. Moreover, the difference
between a peak value of the carrier, having a charge of the opposite polarity to
the toner, going for the photoconductor and an average time of the bias can be
small. Therefore, the movement of the carrier can be restrained and the
possibility of the carrier adhesion to the background of a latent image can
largely be reduced.
The applied bias of the developing unit used in the invention is not
limited as mentioned above, but it is preferable to apply a bias in such a way as
mentioned above in order to obtain images with high resolution without surface
roughness.
The developer contained in the developing unit is the developer

containing the toner according to one of the first and second aspects of the
invention, and it may be one-component or two-component developer. The
toner contained in the developer is the toner according to one of the first and
second aspects of the invention.
- Transferring and Transferring Unit -
Transferring is a step that transfers the visible image to a recording
medium. In a preferable aspect, the first transferring is performed, using an
intermediate transferring member by which the visible image is transferred to
the intermediate transferring member, and the second transfer is performed
wherein the visible image is transferred to the recording medium. In a more
preferable aspect, using toner of two or more colors and preferably of full-color,
and the first transferring is performed by transferring the visible image to the
intermediate transferring member to form a compounded transfer image, and
the second transferring is performed by transferring the compounded transfer
image to the recording medium.
Transferring of the visible image may be carried out, for example, by
charging the latent electrostatic image bearing member (photoconductor) using
a transferring charger, which can be performed by the transferring unit. In a
preferable aspect, the transferring unit contains the first transferring unit
which transfers the visible image to the intermediate transferring member to
form a compounded transfer image, and the second transferring unit which
transfers the compounded transfer image to the recording medium.

The intermediate transferring member is not limited and may be
selected from known transferring members and preferred examples include
transfer belts.
The stationary friction coefficient of intermediate transferring member
is preferably 0.1 to 0.6 and more preferably 0.3 to 0.5. The volume resistance of
intermediate transferring member is preferably more than several Ώ cm and
less than 103 Ώ cm. By keeping the volume resistance within a range of
several Ώ cm to 103 Ώ cm, the charge over intermediate transferring member
itself can be prevented and the charge given by the charging unit is unlikely to
remain on the intermediate transferring member. Therefore transfer
nonuniformity at the time of secondary transferring can be prevented and the
application of transfer bias at the time of secondary transferring becomes
relatively easy.
The materials making up the intermediate transferring member is not
particularly limited, and may be selected from known materials accordingly.
Examples are named hereinafter, (1) Materials with high Young's modulus
(tension elasticity) used as a single layer belt such as polycarbonates (PC),
polyvinylidene fluoride (PVDF), polyalkylene terephthalate (PAT), blend
materials of PC/PAT, ethylene tetrafluoroethylene copolymer (ETFE)/PC, and
ETFE/PAT, thermosetting polyimides of carbon black dispersion, and the like.
These single layer belts having high Young's modulus are small in their
deformation against stress during image formation and are particularly

advantageous in that registration error is least likely to occur during color image
formation. (2) A double or triple layer belt using above-described belt having
high Young's modulus as a base layer, added with a surface layer and an
optional intermediate layer around the peripheral side of the base layer. The
double or triple layer belt has a capability of preventing dropouts in a lined
image that is caused by hardness of the single layer belt. (3) A belt with
relatively low Young's modulus that incorporates a rubber or an elastomer.
This belt is advantageous in that there is almost no print defect of unclear center
portion in a line image due to its softness. Additionally, by making width of the
belt wider than drive roller or tension roller and thereby using the elasticity of
edge portions that extend over rollers, it can prevent meandering of the belt. It
is also cost effective for not requiring ribs or units to prevent meandering.
Conventionally, intermediate transfer belts have been adopting fluorine
resins, polycarbonate resins, polyimide resins, and the like," however, recently,
elastic belts in which elastic members are used in all layers or a part thereof are
used as the intermediate transfer belts. There are some issues over transfer of
color images by resin belt as described below.
Color images are typically formed by four colors of color toners. In one
color image, toner layers of layer 1 to layer 4 are formed. Toner layers are
pressurized as they pass through the primary transferring (in which toner is
transferred to the intermediate transfer belt from the photoconductor) and the
secondary transferring (in which toner is transferred to the sheet from the

intermediate transfer belt), and the cohesive force among toner particles
increases. As the cohesive force increases, phenomena such as dropouts of
letters or dropouts of edges of solid images are likely to occur. Since resin belts
are too hard to deform corresponding to the toner layers, they tend to compress
the toner layers and therefore letter drop outs are likely to occur.
Recently, the demand toward printing full color images on various types
of paper such as Japanese paper or the paper having a rough surface is
increasing. However, the paper having a rough surface is likely to have a gap
between toner and sheet at the time of transferring and therefore leading to
transfer errors. When the transfer pressure of secondary transfer section is
increased in order to increase adhesiveness, the cohesive force of the toner layers
becomes high, resulting in the letter drop outs as described above.
Elastic belts are used for the following purpose. Elastic belts deform
corresponding to the surface roughness of toner layers and the sheet having low
smoothness in the transfer section. In other words, since elastic belts deform
complying with local roughness and an appropriate adhesiveness can be
obtained without excessively increasing the transfer pressure against toner
layers, it is possible to obtain transfer images having excellent uniformity with
no letter drop outs even with the paper of low flatness.
The resin of the elastic belts is not limited and may be selected
accordingly. Examples thereof include polycarbonates, fluorine resins (ETFE,
PVDF), styrene resins (homopolymers and copolymers including styrene or

substituted styrene) such as polystyrene, chloropolystyrene,
poly α-methylstyrene, styrene-butadiene copolymer, styrene-vinyl chloride
copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer,
styrene-acrylate copolymers (styrene-methyl acrylate copolymer, styrene-ethyl
acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate
copolymer, and styrene-phenyl acrylate copolymer), styrene-methacrylate
copolymers (styrene-methyl methacrylate copolymer, styrene-ethyl
methacrylate copolymer, styrene-phenyl methacrylate copolymer, and the like),
styrene-achloromethyl acrylate copolymer, styrene-acrylonitrile acrylate
copolymer, and the like, methyl methacrylate resin, butyl methacrylate resin,
ethyl acrylate resin, butyl acrylate resin, modified acrylic resins
(silicone-modified acrylic resin, vinyl chloride resin-modified acrylic resin,
acrylic urethane resin, and the like), vinyl chloride resin, styrene-vinyl acetate
copolymer, vinyl chloride-vinyl acetate copolymer, rosin-modified maleic acid
resin, phenol resin, epoxy resin, polyester resin, polyester polyurethane resin,
polyethylene, polypropylene, polybutadiene, polyvinylidene chloride, ionomer
resin, polyurethane resin, silicone resin, ketone resin, ethylene-ethylacrylate
copolymer, xylene resin and polyvinylbutylal resin, polyamide resin, modified
polyphenylene oxide resin, and the like. These may be used alone or in
combination.
Rubber and elastomer of the elastic materials are not limited and may
be selected accordingly. Examples thereof include butyl rubber, fluorine rubber,

acrylic rubber, ethylene propylene rubber (EPDM), NBR,
acrylonitrile-butadiene-styrene natural rubber, isoprene rubber,
styrene-butadiene rubber, butadiene rubber, ethylene-propylene rubber,
ethylene-propylene terpolymer, chloroprene rubber, chlorosufonated
polyethylene, chlorinated polyethylene, urethane rubber, syndiotactic
1,2-polybutadiene, epichlorohydrin rubber, silicone rubber, fluorine rubber,
polysulfurized rubber, polynorbornen rubber, hydrogenated nitrile rubber,
thermoplastic elastomers (polystyrene elastomers, polyolefin elastomers,
polyvinyl chloride elastomers, polyurethane elastomers, polyamide elastomers,
polyurea elastomers, polyester elastomers, and fluorine resin elastomers), and
the like. These may be used alone or in combination.
The conductive agents for resistance adjustment are not limited and
may be selected accordingly. Examples thereof include carbon black, graphite,
metal powders such as aluminum, nickel, and the like and electric conductive
metal oxides such as tin oxide, titanium oxide, antimony oxide, indium oxide,
potassium titanate, antimony tin oxide (ATO), indium tin oxide (ITO), and the
like. The conductive metal oxides may be coated with insulating particles such
as barium sulfate, magnesium silicate, calcium carbonate, and the like. The
conductive agents are not limited to those mentioned above.
Materials of the surface layer are required to prevent contamination of
the photoconductor by elastic material as well as to reduce the surface friction of
the transfer belt so that toner adhesion is lessened while cleaning ability and the

secondary transfer property are improved. Materials which reduces surface
energy and enhances lubrication by the use of alone or combination of
polyurethane, polyester, epoxy resin, and the like may be dispersed for use.
Examples of such materials include alone, combination of two or more or
combination of different particle diameters of powders or particles such as
fluorine resin, fluorine compound, carbon fluoride, titanium dioxide, silicon
carbide, and the like. In addition, it is possible to use a material such as
fluorine rubber that is treated with heat so that a fluorine-rich layer is formed
on the surface and the surface energy is reduced.
Examples of manufacturing processes of the belts include, but not
limited to centrifugal forming in which material is poured into a rotating
cylindrical mold to form a belt, spray application in which a liquid paint is
sprayed to form a film, dipping method in which a cylindrical mold is dipped into
a solution of material and then pulled out, injection mold method in which
material is injected between inner and outer mold, a method in which a
compound is applied onto a cylindrical mold and the compound is vulcanized
and grounded. In general, two or more processes are combined for
manufacturing belts.
Methods to prevent elongation of the elastic belt include using a core
resin layer that is difficult to elongate on which a rubber layer is formed,
incorporating a material that prevents elongation into the core layer, and the
like, but the methods are not particularly limited to the manufacturing

processes.
Examples of the materials constructing the core layer that prevent
elongation include alone or combination of natural fibers such as cotton, silk and
the like: synthetic fibers such as polyester fibers, nylon fibers, acrylic fibers,
polyolefin fibers, polyvinyl alcohol fibers, polyvinyl chloride fibers,
polyvinylidene chloride fibers, polyurethane fibers, polyacetal fibers,
polyfluoroethylene fibers, phenol fibers, and the like; inorganic fibers such as
carbon fibers, glass fibers, boron fibers, and the like, metal fibers such as iron
fibers, copper fibers, and the like, and materials that are in a form of a weave or
thread may be used. It should be noted that the materials are not limited to
those described above.
A thread may be one or more of filaments twisted together, and any
twisting and plying forms are accepted such as single twisting, multiple twisting,
doubled yarn, and the like. Further, fibers of different materials selected from
above-mentioned group may be spun together. The thread may be treated-
before use in such a way that it becomes electrically conductive. On the other
hand, the weave may be of any type including plain knitting, and the like. It is
possible to use a union weave for making it electrically conductive.
The manufacturing process of the core layer is not particularly limited.
Examples include a method in which a weave that is woven in a cylindrical
shape is placed on a mold or the like and a coating layer is formed on top of it, a
method in which a cylindrical weave is dipped in a liquid rubber or the like so

that coating layer(s) is formed on one side or on both sides of the core layer and a
method in which a thread is wound helically to a mold or the like in an arbitrary
pitch, and then a coating layer is formed thereon.
If the elastic layer is too thick, elongation and contraction of the surface
becomes large and may cause cracks on the surface layer depending on the
hardness of the elastic layer. Moreover, as the amount of elongation and
contraction increases, the size of images are also elongated and contracted
significantly. Therefore, too much thickness, about 1mm or more, is not
preferable.
The transferring units of the first and the second transferring
preferably contain an image-transferring unit which releases the visible image
formed on the photoconductor to the recording-medium side by charging.
There may be one, two or more of the transferring unit.
The transferring unit may be a corona transferring unit based on corona
discharge, transfer belt, transfer roller, pressure transfer roller, or adhesion
transferring unit, for example.
The recording medium is not limited as long as it is capable of
transferring unfixed images after development and may be selected accordingly.
The recording medium is typically plain paper, and other materials such as
polyethylene terephthalate (PET) sheets for overhead projector (OHP) may be
utilized.
The fixing is a step that fixes the visible image transferred to the

recording medium using a fixing unit. The fixing may be carried out for each
color when being transferred to the recording medium, or simultaneously when
all colors are being laminated.
The fixing unit is not limited and may be selected accordingly, however
it is preferably known heat application and pressurization unit. Examples of
such unit include a combination of heating roller and pressure roller, and a
combination of heating roller, pressure roller, and endless belt, and the like.
The heating temperature in the heat application and pressurization
unit is preferably 80°C to 200°C.
Further, known optical fixing unit may be used in addition to or in place
of fixing and fixing unit, depending on the application.
In a preferable aspect, the fixing unit is a heat fixing unit which fixes a
toner image on a recording medium while the recording medium is passed
between a heating member and a pressure member and is transported.
In this case, it is preferable that the heat fixing unit comprises a
cleaning member which removes the toner adhered to at least one of the heating
member and the pressure member and that the surface pressure (roller
load/contact area) applied between the heating member and pressure member is
1.5x105Pa or less.
As shown in FIG. 20, the fixing unit is, for example, a heat fixing unit in
which a recording medium is passed between a heating member 230 and
pressure member 232 and while the recording medium being transported, toner

images on the recording medium are fixed. The heat fixing unit comprises a
cleaning member 274 which removes toners adhered to the heating member and
the surface pressure (roller load/contact area) applied between the heating
member and pressure member is adjusted to 1.5x105 Pa or less. Higher surface
pressure improves the fixing and/or prevents hot offset in a wider range;
however, strong pressure cause e.g. crumple on a paper easily. The cleaning
member 274 may be directly brought into contact with the heating member 230
or pressure member 232 to remove toners adhered thereto, but not limited to
this case, as shown in this FIG. 20, the cleaning member may remove toners
adhered to the pressure member 232 via a toner removing member 284.
Alternatively, the cleaning member may remove toners adhered to the heating
member 232 via a toner removing member 284 to be brought into contact with
the heating member 230 although drawing is omitted.
In a preferable aspect, the fixing unit comprises a heating member
equipped with a heat generator, a heating member equipped with a heat
generator; a film which contacts with the heating member,' and a pressure
member which makes pressure contact with the heating member via the film,
wherein a recording medium, on which an unfixed image is formed after
electrostatic transfer, is passed between the film and the pressure member to
thereby heat and fix the unfixed image.
Such fixing unit includes, for example, so-called surf fixing device, in
which a fixing film is rotated to fix an image, as shown in FIG. 13.

In this surf fixing device, the fixing film 351 is a heat resistant film
having the shape of an endless belt, which is spanned around a driving roller
356, driven roller 357 and heating member 352 which is fixedly supported by a
heater supporter located between and below both of these rollers.
The driven roller 357 also serves as a tension roller of the fixing film,
and the fixing film 351 rotates clockwise due to a clockwise rotation, shown in
the figure, of the driving roller. This rotational speed of the fixing film, is
adjusted to be equivalent to the speed of a transfer material at a fixing nip area
L where a pressure roller and the fixing film contact each other.
Here, the pressure roller has a rubber elastic layer having good
releasability such as silicone rubbers, and rotates counterclockwise while
pressure contacting the fixing nip area L at an overall contact pressure of from 4
kg to 10 kg.
Such film that is excellent in heat resistance, releasability and
durability is preferable as the fixing film 351, and its total thickness is not more
than 100 µm, preferably, not more than 40 µm. Examples include a monolayer
film of heat resistant resin such as polyimide, polyetherimide, polyethersulfide
(PES), PFA (tetrafluorostyrene-peifluoroaliylvinylether copolymer resin), or the
like; or multi-layer film comprising, for example, a 20 µm thick base layer, and,
in the side coming in contact with the image, a 10 µm thick parting layer of
fluoro-resin such as PTFE (tetrafluoro-ethylene resin), PAF, or the like, which is
coated on the base layer and contains electrically conductive material, or an

elastic layer of e.g. a fluorocarbon rubber or a silicone rubber, which is coated on
the base layer.
In FIG. 13, the heating member 352 in this aspect is composed of a flat
substrate 353 and a fixing heater 355, and the flat substrate 353 is formed of a
material having a high heat conductivity and a high electric resistance such as
alumina. A fixing heater formed of a resistance heat generator is arranged on a
surface of the heating member contacting the fixing film in the longitudinal
direction. The fixing heater is one obtained by coating an electric resistant
material such as Ag/Pd and Ta2N by e.g. a screen printing so as to have a linear
shape or belt shape. Both ends of the fixing heater have electrodes (not shown)
and the resistance heat generator generates a heat when electricity passes
though the electrodes. Further, a fixing temperature sensor 358 formed of a
thermistor is provided to the substrate on the surface opposite to the surface on
which the fixing heater is arranged.
Temperature information of the substrate detected by the fixing
temperature sensor 358 is transmitted to a controller (not shown), then an
electric energy supplied to the fixing heater by the controller, and the heating
member is controlled to a predetermined temperature.
The fixing unit is not limited to the above-mentioned surf fixing device?"
however, it is preferable to use the surf fixing device because of availability of
image forming apparatus such that a fixing unit which is efficient and can
shorten the rise time.

In a preferable aspect, the fixing unit comprises a heating roller, a
fixing roller, an endless belt-like toner heating medium, and a pressure roller,
wherein the heating roller is formed of a magnetic metal and is heated by
electromagnetic induction, the fixing roller is arranged parallel to the heating
roller, the toner heating medium is spanned over the heating roller and the
fixing roller, is heated by the heating roller, and is rotated by these rollers, the
pressure roller is brought into pressure contact with the fixing roller via the
toner heating medium and rolls in the forward direction towards the toner
heating medium to form a fixing nip portion, and wherein a recording medium,
on which an unfixed image is formed after electrostatic transfer, is passed
between the toner heating medium and the pressure member to thereby heat
and fix the unfixed image.
Suitable examples of such fixing unit include the fixing unit according to
an electromagnetic induction heating (IH) process as shown in FIG. 14.
The IH fixing unit used was so-called electromagnetic induction heating
fixing unit (fixing unit according to an IH process) in which a heating unit
thereof is, as shown in FIG. 14, a unit configured to cause a heating member
containing a metal member to generate heat by electromagnetic induction,
namely, the Joule heat caused by eddy current generated to a magnetic metal
member due to an alternating magnetic field.
The image-fixing apparatus shown in FIG. 14 comprises a heating roller
301, fixing roller 302, heat resistant belt (toner heating medium) 303, and

pressure roller 304. The heating roller 301 is heated by electromagnetic
induction of an induction heating unit 306. The fixing roller 302 is arranged
parallel to the heating roller 301. The endless heat resistant belt 303 is
spanned over the heating roller 301, fixing roller 302 and is heated by the
heating roller 301, and rolls in the arrow A direction by the rolling of one of these
roller. The pressure roller 304 is brought into pressure contact with the fixing
roller 302 via the belt 303, and rolls in the forward direction towards the belt
303.
The heating roller 301 comprises hollow circular cylindrical magnetic
metal member made of, for example, iron, cobalt, nickel, or alloys of these metals,
and this configuration enables low thermal capacity and fast temperature
rising.
The fixing roller 302 comprises a cored bar 302a made of metal such as
stainless-steel and an elastic member 302b which is made of silicon rubber
having heat resistance in solid form or in foam form and coats the cored bar
302a. In order to form contact parts with a predetermined width between the
pressure roller 304 and the fixing roller 302 by a pressing force from the
pressure roller 304, the outside diameter of the fixing roller is set to larger than
that of the heating roller 301. This configuration makes the thermal capacity
of the heating roller 301 to be smaller than that of the fixing roller 302, and thus
the heating roller 301 is rapidly heated and warm up time is shortened.
The belt 303 which is spanned over the heating roller 301 and the fixing

roller 302, is heated at a contact site W1 between itself and the heating roller
301 which is heated by the induction heating unit 306. Then, by rolling of
rollers 301 and 302, inside of the belt 303 is consecutively heated and as a result,
the entire belt is heated. The pressure roller 304 comprises a cored bar 304a
which is a circular member made of metal having good heat conductance such as,
for example, copper or aluminum; and an elastic member 304b which is
arranged on the surface of this cored bar 304a and has high heat resistance and
toner releasing properties. Besides the above-mentioned metals, stainless
(SUS) may be used in the cored bar 204a.
The pressure roller 304 presses the fixing roller 302 via the belt 303 to
form a fixing nip portion N. In this aspect, the pressure roller 304 has higher
hardness than the fixing roller 302, and thus the pressure roller 304 makes
inroads into the fixing roller 302 (and belt 303), which causes the recording
medium 311 to be arranged along the circumferential shape of the surface of the
pressure roller 304. In this way, the effect that the separation of the recording
medium 311 from the belt 303 is facilitated is achieved.
The induction heating unit 306 which heats the heating roller 301 by
means of electromagnetic induction comprises, as shown in FIGS. 14, 15A and
15B, an exciting coil 307 as a magnetic field generating unit, and a coil guide
plate 308 around which the exciting coil 307 is winded. The coil guide plate 308
is closely arranged to the outer circumferential surface of the heating roller 301
and is in a half cylinder shape. As shown in FIG.15B, a long piece of wire rod

for an exciting coil is alternately winded along the coil guide plate 308 in the
axial direction of the heating roller 301 to form the exciting coil 307. Note that
the oscillation circuit of the exciting coil 307 is connected to a frequency-variable
driving power source (not shown). Outside the exciting coil 307, an exciting coil
core 309 which is formed of a ferromagnetic material such as ferrite and is in a
half cylinder shape is fixed to an exciting coil core supporting member 310 and
closely arranged to the exciting coil 307. Note that an exciting coil core 309 for
use in this aspect has a relative magnetic permeability of 2,500. A
high-frequency alternating current of 10 to 1 MHz, and preferably 20 kHz to 800
kHz is supplied from the driving power source to the exciting coil 307, thereby
an alternating magnetic field is generated. The alternating magnetic field
works on the heating roller 301 and the heat generating layer of the belt 303 in
the contact region W1 of the heating roller 301 and the fixing belt 303 and in the
vicinity thereof. Inside them, eddy currents I flow in the direction B preventing
change of the alternating magnetic field. This eddy currents I cause to
generate the Joule heat depending on the resistance of the heat roller 201 and
the heat generation layer of the belt 303, i.e., mainly in the contact region of the
heat roller 301 and the belt 303 and in the vicinity thereof, the belt 303
comprising the heat roller 301 and the heat generating layer is heated by means
of electromagnetic induction.
The inner surface temperature of the thus-heated belt 303 is detected by
means of temperature detecting means 305 which is arranged in contact with

the inner surface of the belt 303 in the vicinity of the entrance of the fixing nip
portion N and comprises temperature-sensitive element having high thermal
responsiveness such as a thermistor.
The fixing unit used in the invention is not limited to above-mentioned
fixing unit according to an IH process. However, it is preferable to use a fixing
unit according to an IH process because it has higher efficiency of heat transfer
than that of the hear roller type fixing unit, enabling the shortening of warm-up
time and an image forming apparatus, in which a fixing unit allowing quick
start-up or energy-saving is utilized, is achieved.
The charge-eliminating is a step that applies a discharge bias to the
photoconductor to discharge it, and may be performed by a charge-eliminating
unit.
The charge-eliminating unit is not particularly limited as long as it is
capable of applying discharge bias to the photoconductor such as discharge
lamps, and may be selected from known charge-eliminating units accordingly.
The cleaning is a step in which residual electrophotographic toner on
the latent electrostatic image bearing member is removed, and typically
performed by a cleaning unit.
Any known cleaning unit that is capable of removing residual
electrophotographic toner on the latent electrostatic image bearing member may
be used, the cleaning unit may be properly selected from known cleaner and
examples include magnetic brush cleaner, electrostatic brush cleaner, magnetic

roller cleaner, blade cleaner, brush cleaner, and web cleaner, etc.
The recycling is a step in which the electrophotographic color toner
removed by the cleaning is recycled for use in the developing, and typically
performed by a recycling unit.
The recycling unit may be properly selected from known transport
units.
The controlling is a step in which the respective processes are controlled
and typically carried out by a controlling unit.
Any known controlling unit that is capable of controlling the
performance of each unit may be selected accordingly. Examples include
instruments such as sequencers or computers, etc.
An aspect of the operation of the image forming method performed by
the image forming apparatus of the invention is described referring to FIG. 2.
The image forming apparatus 100 shown in FIG. 2 is equipped with the
photoconductor drum 10 (hereafter referred to as "photoconductor 10") as a
latent electrostatic image bearing member, the charge roller 20 as a charging
unit, the exposure apparatus 30 as an exposure unit, the developing unit 40 as a
developing unit, the intermediate transferring member 50, the cleaning device
60 having a cleaning blade as a cleaning unit and the discharge lamp 70 as a
discharging unit.
The intermediate transferring member 50 is an endless belt that is
being extended by the three roller 51 placed inside the belt and designed to be

moveable in arrow direction. A part of three roller 51 function as a transfer
bias roller that can imprint a specified transfer bias, the primary transfer bias,
to the intermediate transferring member 50. The cleaning unit 90 with a
cleaning blade is placed near the intermediate transferring member 50, and the
transfer roller 80, as a transferring unit which can imprint the transfer bias for .
transferring the developed image, toner image (second transferring), onto the
transfer paper 95 as the final transfer material, is placed face to face with the
cleaning unit 90. In the surrounding area of the intermediate transferring
member 50, the corona charger 58, for charging toner image on the intermediate
transferring member 50, is placed between contact area of the photoconductor
10 and the intermediate transferring member 50 and contact area of the
intermediate transferring member 50 and the transfer paper 95 in the rotating
direction of the intermediate transferring member 50.
The development unit 40 is constructed with developing belt 41 as a
developer bearing member, black developing unit 45K, yellow developing unit
45Y, magenta developing unit 45M and cyan developing unit 45C that are
juxtapositioned in the surrounding area of developing belt 41. The black
developing unit 45K is equipped with developer container 42K, developer
feeding roller 43K and developing roller 44K whereas yellow developing unit
45Y is equipped with developer container 42Y, developer feeding roller 43Y and
developing roller 44Y. The magenta developing unit 45M is equipped with
developer container 42M, developer feeding roller 43M and developing roller

44M whereas the cyan developing unit 45C is equipped with developer
container 42C, developer feeding roller 43C and developing roller 44C. The
developing belt 41 is an endless belt and is extended between a number of belt
rollers as rotatable and the part of developing belt 41 is in contact with the
photoconductor 10.
For example, the charge roller 20 charges the photoconductor drum 10
evenly in the image forming apparatus 100 as shown in FIG. 2. The exposure
apparatus 30 exposes imagewise on the photoconductor drum 10 and forms a
latent electrostatic image. The latent electrostatic image formed on the
photoconductor drum 10 is then developed with the toner fed from the
developing unit 40 to form a toner image. The toner image is then transferred
onto the intermediate transferring member 50 by the voltage applied from the
roller 51 as the primary transferring and it is further transferred onto the
transfer paper 95 as the secondary transferring. As a result, a transfer image
is formed on the transfer paper 95. The residual toner on the photoconductor
10 is removed by the cleaning unit 60 and the charge built up over the
photoconductor 10 is temporarily removed by the discharge lamp 70.
The other aspect of the operation of image forming methods of the
invention by image forming apparatuses of the invention is described referring
to FIG. 3. The image forming apparatus 100 as shown in FIG. 3 has the same
lineups and effects as the image forming apparatus 100 shown in FIG. 2 except
for the developing belt 41 is not equipped and the black developing unit 45K, the

yellow developing unit 45Y, the magenta developing unit 45M and the cyan
developing unit 45C are placed directly facing the photoconductor 10. The
symbols used in FIG. 3 correspond to the symbols used in FIG. 2.
FIG. 19 shows a schematic configuration of an entire image forming
apparatus provided with a heat fixing unit of the invention and comprising the
toner according to one of the first and second aspects of the invention or
developer. In FIG. 19, symbol 350 refers to a copier main body. An image
scanner 450 is provided thereon and the copier main body 350 is provided on a
sheet bank 500. On the image scanner 450, an automatic document feeder 600
is provided so as to be movable up and down around the fulcrum in the back.
Inside of the copier main body 350, a drum-shaped photoconductor 210
as an image bearing member is provided. A charging device 211, the
developing device 212, a transferring device 213 and the cleaning device 214 are
provided surrounding the photoconductor 210, each being placed in the left of,
below, in the right of and above the photoconductor in the rotating direction of
the photoconductor 210 (counterclockwise) A.
In the developing device 212, the toner of the invention is used as a
toner therein, the toner is deposited using a developing roller to develop the
latent electrostatic image on the photoconductor 210 to an visible image.
The transferring device 213 is constructed such that transfer belt 217 is
spanned around upper and lower rollers 215 and 216, and the transfer belt 217
is brought into contact with the surface of the photoconductor 210 at a transfer

position B.
In FIG. 19, a toner supplying device 220, which supplies a new toner to
the developing device 212, is provided in the left side of the charging device211
and cleaning device 214.
Inside of the copier main body 350, a sheet transport device C is also
provided that transports sheet "S", sent out from a sheet cassette 261 described
later of the sheet bank 500, from lower part to upper part, through the transfer
position B to stack position. The sheet transport device C comprises a sheet
supply path R1, manual sheet feeding path R2, and sheet transport path R.
And on the sheet transport path R, a resist roller 221 is provided at a
upstream position of the photoconductor 210. A heat fixing unit 222 is
provided at a downstream position of the photoconductor 210. In the heat
fixing unit 222 which will be described in detail later, a heating roller (heating
member) 230 and pressure roller (pressure member) 232 are provided.
Further downstream of such heat fixing unit 222, a discharge switching
pawl 234, discharge roller 235, a first pressure roller 236, a second pressure
roller 237, and a roller for providing tear-resistance 238 are provided. And
further ahead, discharge stack part (discharge position) 239 is provided where a
sheet on which images are formed is stacked.
A switch back device 242 is provided to the right side of the copier main
body 350 in the figure. The switch back device 242 comprises the sheet
transport device D having an inverting path R3 and re-transport path R4. The

inverting path R3 branches from the sheet transport path R at the position of
discharge switching pawl 234 and guides to a switch back position 244 equipped
with a pair of switch back rollers 243. The re-transport path R4 guides from
the switch back position 244 back to a resist roller 221 of the sheet transport
path R. The sheet transport device D comprises plural sheet transport rollers
266 which transport a sheet.
A laser writing unit 247 is provided in the left of the developing device
212 in the figure. The laser writing unit 247 comprises a laser light source (not
shown), rotating polygon mirror for scanning 248, polygon motor 249, scanning
optical system 250 such as fθ lens, and the like.
The image scanner 450 comprises a light source 253, plural mirrors 254,
optical lens for imaging 255, image sensor 256 such as CCD, and the like. And
a contact glass 257 is provided on the upper surface.
To the automatic document feeder 600 on the contact glass 257, a
document set table (not shown) is provided at the position where a document is
placed and a document stack (not shown) is provided at the discharge position.
The automatic document feeder 600 is also equipped with a sheet transport
device comprising a document transport path (not shown) which transports a
document sheet from the document set table through reading position on the
contact glass 257 of the image scanner 450 to the document stack. The sheet
transport device is equipped with a plurality of sheet transport rollers (not
shown) which transports document sheets.

The sheet bank 500 is equipped with a plurality of sheet cassettes 261 in
which sheets "S" such as a sheet, OHP film, etc. serving as a recording medium
are placed. To each sheet cassette 261, corresponding pick-up roller 262,
feeding roller 263, and separating roller 264 are provided. The
above-mentioned sheet supply path R1, leading to the sheet transport path R of
main body 350, is formed in the right of a plurality of sheet cassettes 261 in the
figure. The sheet supply path R1 is also equipped with a sheet transport roller
266 (rotation body for transporting sheet) which transport a sheet.
A manual sheet feeding section 268 is provided to the right side of the
copier main body 350 in the figure. A manual sheet tray 267 is provided so as
to be opened and closed to the manual sheet feeding section 268, which is also
equipped with the above-mentioned manual sheet feeding path R2 guiding a
sheet, set manually on the manual sheet tray 267. To the manual sheet tray
267, a pick-up roller 262, feeding roller 263, and separating roller 264 are
provided in a similar way.
When an original is copied using this copier, a main switch (not shown)
is switched on and the original is set to the document table of the automatic
document feeder 600. When a book is copied, for example, automatic document
feeder 600 is opened, an original is set directly on the contact glass 257 of the
image scanner 450, automatic document feeder 600 is closed and pushed down.
By pushing the start switch (not shown), the document is transported
by a sheet transport roller through a document transport path and moved onto

the contact glass 257 when the document is set on the automatic document
feeder 00. The image scanner 450 is then activated, reads the content of the
document and the document is discharged on the document stack. On the
other hand, the image scanner 450 is activated immediately when an original is
set onto the contact glass 257.
When the image scanner 450 is activated, a light source 253 of the
image scanner 450 moves along the contact glass 257 and the light from the
light source 253 is reflected by the surface of an original. The reflected light is
reflected by a plurality of mirrors 254, passes through the optical lens for
imaging 255, enters an image sensor 256, and the image sensor 256 reads the
content of the original.
Simultaneously, the photoconductor 210 is rotated by a photoconductor
drive motor (not shown), in case of the example shown in the figure, first, the
surface is uniformly charged by the charging device 211 in which a charge roller
is used, then image information is written with a laser writing unit 247 by
irradiating with laser light according to the content of the original scanned by
the above-mentioned image scanner 450. A latent electrostatic image is formed
on the surface of the photoconductor 210, and after that, toner is adhered by the
developing device 212 to make the latent electrostatic image a visible image.
Simultaneously with the push of start switch, sheets "S" are sent out by
the pick-up roller 262 from the sheet cassette 261 corresponding to the selected
size of a plurality of sheet cassettes 261 accommodated in the sheet bank 500,

and are separated one by one by the following feeding roller 263 and separating
roller 264, fed to the sheet supply path R1, transported by the sheet transport
roller 266, guided to the sheet transport path R, and stopped running down to
the resist roller 221. The resist roller 221 is rotated in synchronism with the
rotation of the aforementioned visual toner image on the photoconductor 210
thereby a sheet being fed in the right of the photoconductor 210. Alternatively,
the manual sheet tray 267 of the manual sheet feeding section 268 is opened
and sheets, set manually on the manual sheet tray 267, are sent out by the
pick-up roller 262, separated one by one by the following feeding roller 263 and
separating roller 264, fed to the manual sheet feeding path R2, transported by
the sheet transport roller 266, guided to the sheet transport path R, and fed in
the right of the photoconductor 210 by the resist roller 221 in synchronism with
the rotation of the photoconductor 210.
Then the toner image on the photoconductor 210 is transferred onto the
sheet "S", fed in the right of the photoconductor 210, by, in case of the example
shown in the figure, the transferring device 213, at the transfer position B to
form an image. The residual toner on the photoconductor 210 after the image
transfer is removed by the cleaning device 214 and cleaned, residual potential
on the photoconductor 210 is removed by a discharging device (not shown) to
prepare for the next image forming, which starts from the charging device 211.
The sheet "S" after the image transfer is transported by the transfer belt
217, fed to the heat fixing unit 222, passed between the heating roller 230 and

pressure roller 232 and while the sheet being transported, heat and pressure are
applied by them to fix the toner image on the sheet "S". Subsequently, the
sheet is provided with tear-resistance through the discharge roller 235, first
pressure roller 236, second pressure roller 237, and roller for providing
tear-resistance 238, discharged on the discharge stack part 239, and stacked
there.
When images are formed on both sides of the sheet, the discharge
switching pawl 234 is switched. The sheet, on the surface of which a toner
image is transferred, is fed from the sheet transport path R to the inverting path
R3l; transported by the sheet transport roller 266 to the switch back position 244;
switched back by a switch back roller 243; thereby inverted, introduced to the
re-transport path R4>' transported by the sheet transport roller 266, guided
again to the sheet transport path R; and images are also transferred on the back
side of the sheet in the same way as described above.
There are two types of tandem electrophotographic apparatus by which
the image forming of the invention is performed by the image forming
apparatus of the invention. In direct transfer type, images on the
photoconductor 1 is transferred sequentially by the transferring unit 2 to the
sheet "s" which is being transported by the sheet transport belt 3 as shown in
FIG. 4. In the indirect transfer type, images on the photoconductor 1 is
temporarily transferred sequentially by the primary transferring unit 2 to the
intermediate transferring member 4 and then all the images on the

intermediate transferring member 4 are transferred together to the sheet "s" by
the secondary transferring unit 5 as shown in FIG. 5. The transferring unit 5
is generally a transfer/transport belt; however roller types may be used.
The direct transfer type, compared to the indirect transfer type, has a
drawback of growing in size in the direction of sheet transportation because the
paper feeding unit 6 must be placed on the upper side of the tandem image
forming apparatus T where the photoconductor 1 is aligned, whereas the fixing
unit 7 must be placed on the lower side of the apparatus. On the other hand, in
the indirect transfer type, the secondary transfer site may be installed relatively
freely, and the paper feeding unit 6 and the fixing unit 7 may be placed together
with the tandem image forming apparatus T making it possible to be downsized.
To avoid size-growing in the direction of sheet transportation, the fixing
unit 7 must be placed close to the tandem image forming apparatus T.
However, it is impossible to place the fixing unit 7 in a way that gives enough
space for sheet "s" to bend, and the fixing unit 7 may affect the image forming on
the upper side by the impact generated from the leading end of the sheet "s" as it
approaches the fixing unit 7 (this becomes distinguishable with a thick sheet), or
by the difference between the transport speed of the sheet when it passes
through the fixing unit 7 and when it is transported by the transfer/transport
belt. The indirect transfer type, on the other hand, allows the fixing unit 7 to
be placed in a way that gives sheet "s" an enough space to bend and the fixing
unit 7 has almost no effect on the image forming.

For above reasons, the indirect transfer type of the tandem
electrophotographic apparatus is particularly being emphasized recently.
And this type of color electrophotographic apparatus as shown in FIG. 5,
prepares for the next image forming by removing the residual toner on the
photoconductor 1 by the photoconductor cleaning unit 8 to clean the surface of
the photoconductor 1 after the primary transferring. It also prepares for the
next image forming by removing the residual toner on the intermediate
transferring member 4 by the intermediate transferring member cleaning unit 9
to clean the surface of the intermediate transferring member 4 after the
secondary transferring.
The tandem image forming apparatus 100 as shown in FIG. 6 is a
tandem color image forming apparatus. The tandem image forming apparatus
120 is equipped with the copier main body 150, the feeding paper table 200, the
scanner 300 and the automatic document feeder (ADF) 400.
The intermediate transferring member 50 in a form of an endless belt is
placed in the center part of the copier main body 150. The intermediate
transferring member 50 is extended between the support roller 14,15 and 16 as
rotatable in the clockwise direction as shown in FIG. 6. The intermediate
transferring member cleaning unit 17 is placed near the support roller 15 in
order to remove the residual toner on the intermediate transferring member 50.
The tandem developing unit 120 is placed on the intermediate transferring
member 50. In the tandem developing unit, four image forming units 18,

yellow, cyan, magenta and black, are positioned in line along the transport
direction in the intermediate transferring member 50, which is being extended
between the support roller 14 and 15. The exposure unit 21 is placed near the
tandem developing unit 120. The secondary transferring unit 22 is placed on
the opposite side where tandem developing unit 120 is placed in the
intermediate transferring member 50. The secondary transfer belt 24, an
endless belt, is extended between a pair of the roller 23 and the transfer paper
transported on the secondary transfer belt 24 and the intermediate transferring
member 50 are accessible to each other in the secondary transferring unit 22.
The fixing unit 25 is placed near the secondary transferring unit 22.
The sheet inversion unit 28 is placed near the secondary transferring
unit 22 and the fixing unit 25 in the tandem image forming apparatus 100, in
order to invert the transfer paper to form images on both sides of the transfer
paper.
The full-color image formation, color copy, using the tandem developing
unit 120 is explained. At the start, a document is set on the document table
130 of the automatic document feeder (ADF) 400 or the automatic document
feeder 400 is opened and a document is set on the contact glass 32 of the scanner
300 and the automatic document feeder 400 is closed.
By pushing the start switch (not shown), the scanner 300 is activated
after the document was transported and moved onto the contact glass 32 when
the document was set on the automatic document feeder 400, or the scanner 300

is activated right after, when the document was set onto the contact glass 32,
and the first carrier 33 and the second carrier 34 will start running. The light
from the light source is irradiated from the first carrier 33 simultaneously with
the light reflected from the document surface is reflected by the mirror of second
carrier 34. Then the scanning sensor 36 receives the light via the imaging lens
35 and the color copy (color image) is scanned to provide image information of
black, yellow, magenta and cyan.
Each image information for black, yellow, magenta and cyan is
transmitted to each image forming unit 18: black image forming unit, yellow
image forming unit, magenta image forming unit and cyan image forming unit,
of the tandem developing unit 120 and each toner image of black, yellow,
magenta and cyan is formed in each image forming unit. The image forming
unit 18: black image forming unit, yellow image forming unit, magenta image
forming unit and cyan image forming unit of the tandem image forming
apparatus 120 as shown in FIG. 7 is equipped with the photoconductor 10:
photoconductor 10K for black, photoconductor 10Y for yellow, photoconductor
10M for magenta and photoconductor 10 C for cyan, the charger 60 that charges
photoconductor evenly, an exposing unit by which the photoconductor is exposed
imagewise corresponding to each color images based on each color image
information as indicated by L in FIG. 7 to form a latent electrostatic image
corresponding to each color image on the photoconductor, the developing unit 61
by which the latent electrostatic image is developed using each color toner: black

toner, yellow toner, magenta toner and cyan toner to form toner images, the
charge-transferring unit 62 by which the toner image is transferred onto the
intermediate transferring member 50, the photoconductor cleaning unit 63 and
the discharger 64. The image forming unit 18 is able to form each
single-colored image: black, yellow, magenta and cyan images, based on each
color image information. These formed images: black image formed on the
photoconductor 10K for black, yellow image formed on the photoconductor 10Y
for yellow, magenta image formed on the photoconductor 10M for magenta and
cyan image formed on the photoconductor 10C for cyan, are transferred
sequentially onto the intermediate transferring member 50 which is being
rotationally transported by the support rollers 14,15 and 16 (the primary
transferring). And the black, yellow, magenta and cyan images are overlapped
to form a synthesized color image, a color transfer image.
In the feeding table 200, one of the feeding rollers 142 is selectively
rotated and sheets (recording paper) are rendered out from one of a plurality of
feeding cassettes in the paper bank 143 and sent out to feeding path 146 after
being separated one by one by the separation roller 145. The sheets are then
transported to the feeding path 148 in the copier main body 150 by the transport
roller 147 and are stopped running down to the resist roller 49. Alternatively,
sheets (recording paper) on the manual sheet tray 51 are rendered out by
rotating a feeding roller 150, inserted into the manual feeding path 53 after
being separated one by one by the separation roller 52 and stopped by running

down to the resist roller 49 in the same way. Generally, the resist roller 49 is
used being grounded; however, it is also usable while bias is imposed for the
sheet powder removal.
The resist roller 49 is rotated in synchronism with the synthesized color
image (color transfer image) on the intermediate transferring member 50, and a
sheet (recording paper) is sent out between the intermediate transferring
member 50 and the secondary transferring unit 22. The color image is then
formed on the sheet (recording paper) by transferring (secondary transferring)
the synthesized color image (color transfer image) by the secondary transferring
unit 22. The residual toner on the intermediate transferring member 50 after
the image transfer is cleaned by the intermediate transferring member cleaning
unit 17.
The sheet (recording paper) on which the color image is transferred and
formed is taken out by the secondary transferring unit 22 and sent out to the
fixing unit 25 in order to fix the synthesized color image (color transfer image)
onto the sheet (recording paper) under the thermal pressure. Triggered by the
switch claw 55, the sheet (recording paper) is discharged by the discharge roller
56 and stacked on the discharge tray 57. Alternatively, triggered by the switch
claw 55, the sheet is inverted by the sheet inversion unit 28 and led to the
transfer position again. After recording an image on the back side, the sheet is
then discharged by the discharge roller 56 and stacked on the discharge tray 57.
The image forming method and image forming apparatus of the

invention can produce high quality images efficiently since the method and
apparatus uses the toner of the invention which corresponds to a
low-temperature fixing system, is excellent in both of offset resistance and
anti-heat preservability and especially, even after a large number of copies are to
be produced over a long period, the toner does not aggregate to each other,
deterioration of flowability, transferability, and fixing ability is extremely rare,
the toner makes it possible to form stable images on any transferring medium
without transfer errors and with good reproducibility, and further does not
contaminate fixing unit and images.
Herein below, with referring to Examples, the invention is explained in
detail and the following Examples should not be construed as limiting the scope
of this invention. All "parts" and "%" are expressed by mass unless indicated
otherwise.
(Example A-1)
-Synthesis of Organic Particle Emulsion-
lb a reaction vessel provided with stirrer and thermometer, 683 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMNOL RS-30 by Sanyo Chemical Industries, Ltd.), 83 parts
of styrene, 83 parts of methacrylic acid, 110 parts of butyl acrylate and 1 part of
ammonium persulphate were introduced, and stirred at 400 rpm for 15 minutes
to give a white emulsion. This was heated, the temperature in the system was
raised to 75°C and the reaction was performed for 5 hours. Next, 30 parts of an

aqueous solution of 1% ammonium persulphate was added, and the reaction
mixture was matured at 75°C for 5 hours to obtain an aqueous dispersion of a
vinyl resin (copolymer of styrene-methacrylic acid-butyl acrylate-sodium salt of
sulfuric acid ester of methacrylic acid ethylene oxide adduct). This is referred
to as "particle dispersion 1".
The volume average particle diameter of particles contained in the
"particle dispersion 1" measured by the particle size distribution measuring
apparatus (LA-920 by Horiba Ltd.) in which laser light scattering technique is
adopted was 105 nm. After drying a part of the "particle dispersion 1", the
resin was isolated. The glass-transition temperature, Tg of the resin was 59°C
and the average molecular mass, Mw was 150,000.
-Preparation of Aqueous Phase-
To 990 parts of water, 80 parts of the "particle dispersion 1," 37 parts of
48.5% aqueous solution of sodium dodecyl diphenylether disulfonic acid
(ELEMINOL MON-7 by Sanyo Chemical Industries, Ltd.) and 90 parts of ethyl
acetate were mixed and stirred together to obtain a milky liquid. This is
referred to as "aqueous phase 1."
-Production of Low Molecular Mass Polyester
In a reaction vessel equipped with condenser tube, stirrer, and nitrogen
inlet tube, 670 parts of bisphenol A ethylene oxide dimolar adduct and 335 parts
of terephthalic acid were placed, and subjected to polycondensation under
normal pressure at 210°C for 10 hours. Thereafter, reaction was performed

under a reduced pressure of 10 mmHg to 15 mmHg for 5 hours and then cooled
to 160°C. Then 46 parts of phthalic anhydride was introduced into the reaction
vessel, and the reaction was performed for 2 hours to obtain 'low molecular
mass polyester 1".
The "low molecular mass polyester 1" had a glass-transition
temperature, Tg, of 43.7°C, average molecular mass, Mw, of 6,700, number
average molecular mass of 3,300 and acid value of 4.4.
Synthesis of Prepolymer-
In a reaction vessel equipped with condenser tube, stirrer, and nitrogen
inlet tube, 410 parts by mass of "low molecular mass polyester 1", 89 parts of
isophorone diisocyanate and 500 parts by mass of ethyl acetate were introduced,
and the reaction was performed at 100°C for 5 hours to synthesize addition
products. In this way, "prepolymer 1" was synthesized.
-Synthesis of Ketimine-
Into a reaction vessel equipped with stirrer and thermometer, 170 parts
of isohorone diamine and 75 parts of methyl ethyl ketone were introduced, and
the reaction was performed at 50°C for 5 hours to obtain blocked amine. This is
referred to as 'ketimine compound 1". The amine value of "ketimine compound
1" was 418.
-Preparation of Masterbatch-
1,200 parts of water, 40 parts of carbon black (REGAL 400R by Cabot
Corporation), 60 parts of polyester resin (RS801 by Sanyo Chemical Industries,

Ltd.) and 30 parts of water were added and mixed in HENSCHEL MIXER (by
Mitsui Mining). Then the mixture was kneaded at 150°C for 30 minutes using
two rollers, and subjected to rolling cooling and crushed with a pulverizer to
obtain carbon black masterbatch. This is referred to as "masterbatch 1".
-Preparation of Oil Phase-
400 parts of "low molecular mass polyester 1", 110 parts of carnauva
wax and 947 parts of ethyl acetate were introduced into a reaction vessel
provided with stirrer and thermometer, and the temperature was raised to 80°C
with stirring, maintained at 80°C for 5 hours, and cooled to 30°C over 1 hour.
Next, 500 parts of "masterbatch 1" and 500 parts of ethyl acetate were
introduced into the reaction vessel and mixed for 1 hour to obtain a lysate.
This is referred to as "raw material solution 1".
1,324 parts of "raw material solution 1" were transferred to a reaction
vessel, and wax was dispersed using a bead mill (Ultra Visco Mill by Aimex Co.,
Ltd.) under the condition of liquid feed rate 1kg/hr, disk circumferential speed
6m/sec, 0.5 mm zirconia beads packed to 80% by volume and 3 passes.
Next, 1,324 parts of 65% ethyl acetate solution of the "low molecular
mass polyester 1" was added and dispersed in 1 pass by the bead mill under the
aforesaid condition to obtain a dispersion. This is referred to as "pigment/wax
dispersion 1".
-Emulsification-
1772 parts of "pigment/wax dispersion 1", 100 parts of 50% ethyl acetate

solution of "prepolymer 1" (number average molecular mass (Mn) 3,800, average
molecular mass (Mw) 15,000, glass-transition temperature (Tg) 60°C, acid value
0.5, hydroxyl value 51, and the content of free isocyanate was 1.53% by mass),
and 8.5 parts of "ketimine compound 1" were placed in a reaction vessel and
mixed at 5,000 rpm for 1 minute using TK homomixer by Tokushu Kika Kogyo
Co., Ltd. Then 1,200 parts of "aqueous phase 1" were added to the reaction
vessel and mixed in the TK homomixer at a rotation speed of 10,000 rpm for 20
minutes to obtain an aqueous medium dispersion. This is referred to as
"emulsion slurry 1".
-Organic Solvent Removal-
The "Emulsion slurry 1" was placed in a reaction vessel equipped with
stirrer and thermometer, then the solvent was removed at 30°C for 8 hours and
the product was matured at 45°C for 4 hours to obtain dispersion of which
organic solvent is removed. This is referred to as "dispersion slurry 1."
-Rinsing and Drying-
After filtering 100 parts of "dispersion slurry 1" under the reduced
pressure, rinsing and drying processes were performed by following procedures.
(1) 100 parts of ion exchange water were added to the filter cake and
mixed in a TK homomixer at a rotation speed of 12,000 rpm for 10 minutes and
filtered.
(2) 100 parts of 10% sodium hydroxide solution were added to the filter
cake of (1) and mixed in a TK homomixer at a rotation speed of 12,000 rpm for

30 minutes and filtered under the reduced pressure.
(3) 100 parts of 10% hydrochloric acid were added to the filter cake of (2)
and mixed in a TK homomixer at a rotation speed of 12,000 rpm for 10 minutes
and filtered.
(4) 300 parts of ion exchange water were added to the filter cake of (3)
and mixed in a TK homomixer at a rotation speed of 12,000 rpm for 10 minutes
and filtered twice to obtain a filter cake.
The filter cake was then dried in a circulating air dryer at 45°C for 48
hours, and sieved through a sieve of 75 µm mesh to obtain a toner-base particle.
This is referred to as "toner-base particle 1".
-Mixture of external additive
100 parts by mass of "toner-base particle 1", obtained as described above,
1.0 part by mass of hydrophobized silica (HDK H2000, by Clariant(Japan)KK)
as an external additive, and 0.5 parts by mass of hydrophobized titanium oxide
(MT150AFM, by Tayca Corporation) were mixed in HENSCHEL MIXER, and
allowed to pass through a sieve of 38 µm mesh to remove coagulation. Thus,
toner was obtained. This is referred to as "toner 1".

For the obtained "toner 1", volume average particle diameter (Dv),
particle size distribution (Dv/Dn), average circularity, 1/2 flown-out temperature
Tma, 1/2 flown-out temperature after melt kneading of toner Tmb, difference
between Tma and Tmb, ΔTm, gel content, molecular mass peak, and

glass-transition temperature (Tg) were measured as follows. Results are
shown in Table 2.

The volume average particle diameter and particle size distribution of a
toner at an aperture diameter of 100 µm was measured using a particle size
meter, Coulter Counter TA-II by Coulter Electronics Ltd. And the figure of
volume average particle diameter / number average particle diameter was
calculated based on these results.

The average circularity of the toner was measured by a flow type
particle image analyzer, FPIA-2100 by Sysmex Corporation. Specifically, the
measurement was performed by adding 0.1 ml to 0.5 ml of alkylbenzene
sulfonate surfactant as a dispersing agent to 100 ml to 150 ml of water from
which solid impurities had been removed in advance, in a container, and then
0.1 g to 0.5 g of each toner was added and dispersed. The dispersion was
subjected to dispersion treatment for 1 minute to 3 minutes using an ultrasonic
disperser by Honda Electronics, and the toner shapes and distribution were
measured by the above apparatus at a dispersion concentration of 3,000/µl to
10,000/µl and the average circularity was calculated from the result above.
melt-kneading of toner, Difference between Tma, and Tmb ΔTm >
The 1/2 flownout temperature of toner was measured using a capillary

type flow tester (CFT500C, by Shimadzu Corporation) under the conditions of
Load 30 kg, Die diameter 1 mm, Temperature rising rate 3°C/min.
The toner was melt-kneaded by batch type kneading using a Labo
Plastomill 4C 150 type (by Toyo Seiki Seisaku-sho, Ltd.). The toner amount
was 45 g, heating temperature 130°C, rotation number 50 rpm, and kneading
time 15 minutes.

The gel content was measured as follows. 1 g of toner was weighed, to
this, 100 g of tetrahydrofuran (THF) was added, and left at 10°C for 20 hours to
30 hours. After 20 hours to 30 hours, gel fraction, THF insoluble components,
absorbed THF as a solvent, and swelled to precipitate, and then this wass
separated with a filter paper. Separated gel fraction was heated at 120°C for 3
hours, absorbed THF was volatilized, and then mass was weighed. Thus, gel
fraction was measured.

Molecular mass peak of the toner was measured as follows. The
column inside the heat chamber of 40°C was stabilized. At this temperature,
THF as a column solvent was drained at a current speed of 1ml/minute and 50µl
to 200µl of THF sample fluid whereof a sample density was adjusted to 0.05% by
mass to 0.6% by mass, was poured and measured. In the measurement of
molecular mass of the sample, a molecular mass distribution of the sample was
calculated from the relationship between log values of the analytical curve made

from several monodisperse polystyrene standard samples and counted numbers.
The standard polystyrene sample for making analytical curves was the one with
a molecular mass of 6x102,2.1x102, 4x102 1.75x104, 5.1x104, 1.1x105, 3.9x105,
8.6x105, 2x106 and 4.48x106 by Toyo Soda Manufacturing Co., Ltd. A refractive
index (RI) detector was used for the detector.

The glass-transition temperature can be measured using TG-DSC
system TAS100 (available from Rigaku DenM Co., Ltd.) according to the
following method. Initially, about 10 mg of toner is placed in an aluminum
sample vessel. The vessel is placed on a holder unit, which is then set in an
electric furnace. The sample is heated from room temperature to 150°C at a
temperature rising rate of 10°C /min. After being allowed to stand at 150°C for
10 minutes, the sample is cooled to room temperature and allowed to stand for
10 minutes. Then, in a nitrogen flow, DSC measurement is carried out using a
differential scanning calorimeter (DSC) while heating the sample to 150°C at a
temperature rising rate of 10°C/min. Glass-transition temperature (Tg) is
determined using the analyzing system of the TG-DSC system TAS-100 system
as a temperature at the intersection of the base line and a tangential line of the
endothermic curve near the glass-transition temperature (Tg).
(Example A-2)
"toner 2" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low

molecular mass polyester 2" having characteristics shown in Table 1.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Comparative Example A-1)
"toner 3" was produced in the same way as in Example A1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 3" having characteristics shown in Table 1 and the
amount of "ketimine compound 1" added was changed to 10.3 parts.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Comparative Example A-2)
"toner 4" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 3" having characteristics shown in Table 1 and the
amount of "ketimine compound 1" added was changed to 10.3 parts.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Comparative Example A-3)
"toner 5" was obtained in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 3" having characteristics shown in Table 1 and the
amount of "ketimine compound 1" added was changed to 4.2 parts.

For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-3)
"toner 6" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 4" having characteristics shown in Table 1.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-4)
"toner 7" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 4" having characteristics shown in Table 1, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the
amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1610 parts and 231 parts, respectively.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-5)
"toner 8" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 5" having characteristics shown in Table 1, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the

amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1705 parts and 154 parts, respectively.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-6)
"toner 9" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 5" having characteristics shown in Table 1, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the
amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1610 parts and 231 parts, respectively, and in the preparation of aqueous phase,
the amount of 48.5% aqueous solution of sodium dodecyl diphenylether
disulfonic acid added was changed to 58 parts.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-7)
"toner 10" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 5" having characteristics shown in Table 1, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the
amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1516 parts and 308 parts, respectively, and in the preparation of aqueous phase,

the amount of 48.5% aqueous solution of sodium dodecyl diphenylether
disulfonic acid added was changed to 58 parts, further 28 parts of 3.0% aqueous
solution of polymeric protective colloid carboxymethylcellulose (Celogen BSH by
Sanyo Chemical Industries, Ltd.) was added in an aqueous phase.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
Example A-8)
"toner 11" was obtained in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 6" having characteristics shown in Table 1 and the
amount of "ketimine compound 1" added was changed to 10.3 parts, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the
amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1762 parts and 108 parts, respectively.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-9)
"toner 12" was produced in the same way as in Example A-1, except that,
"low molecular mass polyester 1" described in Example Al was changed to "low
molecular mass polyester 6" having characteristics shown in Table 1 and the
amount of "ketimine compound 1" added was changed to 6.5 parts, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the

amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1781 parts and 92 parts, respectively.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-10)
"toner 13" was produced in the same way as in Example A-1, except that,
in Example A-1, "low molecular mass polyester 1" was changed to "low
molecular mass polyester 5" having characteristics shown in Table 1, in the
emulsification process, the amount of "pigment/wax dispersion 1" added and the
amount of 50% ethyl acetate solution of "prepolymer 1" added were changed to
1705 parts and 154 parts, respectively, and in the preparation of aqueous phase,
the amount of 48.5% aqueous solution of sodium dodecyl diphenylether
disulfonic acid added was changed to 58 parts, further 28 parts of 3.0% aqueous
solution of carboxymethylcellulose as a polymeric protective colloid was added in
an aqueous phase.
For the obtained toner, characteristics of toner were measured in the
same way as in Example A-1. Results are shown in Table 2.
(Example A-11)
Toner was evaluated in the same way as in Example A-1, except that, in
Example A-10, evaluation machine B was used as an evaluation machine for use
in the evaluation of characteristics of toner. Results are shown in Table 2.





Each developer obtained in Examples and Comparative Examples was
evaluated with the following evaluation machines. Specifically, a full-color
laser printer IPSiO 8000, by Ricoh Company, Ltd., which adopts a method in
which four color developing sections develop each color sequentially on one belt
photoconductor, transferred to an intermediate transferring member
sequentially, and four colors are transferred together to paper, etc., was modified
so that a contact charger, amorphous silicon photoconductor, oilless surf fixing
device are provided, and a vibration bias voltage comprising a DC voltage
superimposed on an AC voltage is applied as a developing bias. Further
modified machines, "evaluation machine A" comprising the photoconductor,
charger, developing unit, and cleaning unit integrally as a process cartridge
and "evaluation machine B" were used for evaluation, "evaluation machine B"
was a modified "evaluation machine A" such that the fixing unit of the
evaluation machine A was modified to an oilless IH fixing unit. In these
Examples and Comparative Examples, same developer was supplied in each of
four color developing sections, and images, etc. were evaluated in a single-color
mode.

Performance of developers obtained in the Examples and Comparative
Examples were evaluated for the following items. Results are shown in Table
3.
(1) Image graininess and fineness

Using the evaluation machine A or B, a photographic image was output
by running 10,000 copies in a single-color mode, and the degree of graininess
and fineness were observed with eyes and evaluated in accordance with the
standards shown below.
[Evaluation Standards]
When the degree was comparable to offset printing, it is described as A,
when slightly inferior to offset printing, as B, when slightly superior to
conventional electrophotographic images, as C, when same degree as
conventional electrophotographic images, as D, and when inferior to
conventional electrophotographic images, as E.
(2) Reproducibility of thin line
After outputting 30,000 copies of an image chart in a single-color mode
with an image occupancy of 50% as running output using the evaluation
machine A or B, thin line image having 600 dpi was produced on the paper type
6000 by Ricoh Company, Ltd. The degree of blur of the thin line was compared
with a grade sample, and evaluated on five levels, ranks 1 to 5.
[Evaluation Standards]
Rank 5 is the most excellent in reproducibility of thin line, and Rank 1 is
poorest. Ranks 5, 4, 3,2, and 1 are displayed as A, B, C, D, and E, respectively.
(3) Dropout in letter image
After outputting 30,000 copies of an image chart in a single-color mode
with an image occupancy of 50% as running output using the evaluation

machine A or evaluation machine B, letter image was produced on the OHP
sheet type DX by Ricoh Company, Ltd. Frequency of dropout in thin line image
of letter, i.e., untransfer of toner was compared with a grade sample, and
evaluated on five levels, ranks 1 to 5 below.
[Evaluation Standards]
When dropout occurred least, it was evaluated as Rank 5, and when
dropout occurred most, it was evaluated as Rank 1. Ranks 5, 4, 3, 2, and 1 are
displayed as A, B, C, D, and E, respectively.
(4) Hot offset resistance and fixing property at low temperatures
Using the evaluation machine A or evaluation machine B, solid images
were produced at a toner adhesive amount of 0.85 ± 0.1mg/cm2 on the transfer
paper of a standard paper and thick paper (type 6200 by Ricoh Company, Ltd.
and Copy Paper 135 by NBS Ricoh Co. Ltd.), and fixing performance was
evaluated. Fixing test was carried out by varying the temperature of a fixing
belt, and upper limit temperature at which hot offset does not occur in the
standard paper was defined as highest fixing temperature. In addition, lowest
fixing temperature was measured using the thick paper. The lowest fixing
temperature was determined as follows" obtained fixed image was subjected to
drawing by means of a drawing tester at a load of 50 g and temperature of the
fixing roller at which images are hardly scratched was defined as lowest fixing
temperature. The highest fixing temperature (hot offset resistance) and lowest
fixing temperature (fixing property at low temperatures) are displayed.

(5) Small amount of offset
After outputting 10,000 copies of an image chart in a single-color mode
with an image occupancy of 50% as running output using a tuned evaluation
machine in which a jig with a cloth was arranged on the fixing belt of evaluation
machine A or B so that the cloth was brought into contact with the fixing belt
was used, smear on the cloth was compared with a grade sample, and evaluated
on five levels, ranks 1 to 5 below. When small amount of offset was hardly
observed, it was evaluated as Rank 5, and when small amount of offset was
observed greatest, it was evaluated as Rank 1.
[Evaluation Standards]
Ranks 5, 4, 3, 2, and 1 are displayed as A, B, C, D, and E, respectively.
(6) Anti-heat preservability
10 g of each toner was weighed and placed in a 20 ml of glass container.
The glass bottles were tapped 100 times and left for 24 hours in a thermostat set
to a temperature of 50°C and a humidity of 80%. Then, the penetration was
measured with a penetration meter according to the following standards.
[Evaluation Standards]
Starting from good penetration, A: 30 mm or more, B: 20 mm to 29 mm,
C: 15 mm to 19 mm, D: 8 mm to 14 mm, E: 7 mm or less.
(7) Toner spent property
After outputting 30,000 copies of an image chart in a single-color mode
with an image occupancy of 50% as running output using the evaluation

machine A or B, 2 g of developer was subjected to air blow and tone was removed.
1 g of remaining carrier and 10 g of methylethylketone were placed in a 20 ml of
glass container, and shaken vigorously with hands 50 times. After the glass
container was left to stand completely, supernatant solution was put in a glass
cell, the transmittance was measured by a fully automatic haze computer
(HGM-200P by Suga Tester Co., Ltd.) and evaluated according to the following
standards.
[Evaluation Standards]
Starting from good transmittance, A: 90% or more, B: 75% to 89%, C:
60% to 74%, D: 45% to 59%, E: 44% or less.



(Example B-1)
-Synthesis of resin fine particle emulsion-
Tb a reaction vessel provided with stirrer and thermometer, 838 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 73 parts
of styrene, 92 parts of methacrylic acid, 130 parts of butyl acrylate and 1 part of
ammonium persulphate were introduced, and stirred at 400 rpm for 15 minutes
to give a white emulsion. This was heated, the temperature in the system was
raised to 75°C and the reaction was performed for 5 hours. Next, 30 parts of an
aqueous solution of 1% ammonium persulphate was added, and the reaction
mixture was matured at 75°C for 5 hours to obtain an aqueous dispersion of a
vinyl resin (copolymer of styrene-methacrylic acid'butyl acrylate-sodium salt of
sulfuric acid ester of methacrylic acid ethylene oxide adduct), "resin fine particle
dispersion 1".
The "resin fine particle dispersion 1" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser light
scattering technique is adopted, and the volume average particle diameter was
90 nm. After drying a part of the "resin fine particle dispersion 1", the resin
was isolated. The glass-transition temperature, Tg of the resin was 57°C and
the average molecular mass, Mw was 200,000.
-Preparation of Aqueous Phase-
To 990 parts of water, 83 parts of the "resin fine particle dispersion 1",

37 parts of 48.5% aqueous solution of sodium dodecyl diphenylether disulfonic
acid (ELEMNOL MON-7 by Sanyo Chemical Industries, Ltd.) and 90 parts of
ethyl acetate were mixed and stirred together to obtain a milky liquid. This is
referred to as "aqueous phase 1."
-Production of Unmodified Polyester
In a reaction vessel equipped with condenser tube, stirrer, and nitrogen
inlet tube, 770 parts of bisphenol A ethylene oxide dimolar adduct and 220 parts
of terephthalic acid were placed, and subjected to polycondensation under
normal pressure at 210°C for 10 hours. Thereafter, reaction was performed
under a reduced pressure of 10mmHg to 15mmHg for 5 hours and then cooled to
160°C. Then 18 parts of phthalic anhydride was introduced into the reaction
vessel, and the reaction was performed for 2 hours to obtain "unmodified
polyester a".
The "unmodified polyester a" had a glass-transition temperature, Tg of
42°C, average molecular mass of 28,000, peak top of 3,500 and acid value of 15.3.
-Production of Prepolymer-
In a reaction vessel equipped with condenser tube, stirrer, and nitrogen
inlet tube, 640 parts of bisphenol A ethyleneoxide dimole adduct, 274 parts of
isophthalic acid, 20 parts of tximellitic anhydride and 2 parts of dibutyl tin oxide
were placed, and the reaction was performed under normal pressure at 230°C
for 8 hours. Further, the reaction was performed with dehydrating under a
reduced pressure of 10mmHg to 15mmHg for 5 hours and then cooled to 160°C.

To this, 32 parts of phthalic anhydride was added, and allowed to react for 2
hours. Next, this was cooled to 80°C and allowed to react with 155 parts of
isophorone diisocyanate in ethyl acetate for 2 hours to obtain
"isocyanate-group containing prepolymer 1".
-Synthesis of Ketimine Compound-
Into a reaction vessel equipped with stirrer and thermometer, 30 parts
of isohorone diamine and 70 parts of methyl ethyl ketone were introduced, and
the reaction was performed at 50°C for 5 hours to obtain "ketimine compound 1".
-Preparation of Masterbatch (MB)-
1,200 parts of water, 540 parts of carbon black (Printex 35 by Degussa
AG) [DBP oil absorption amount=42 ml/100mg, pH=9.5] and 1,200 parts of
polyester resin were added and mixed by means of a pressure kneader. Then
the mixture was kneaded at 150°C for 30 minutes using two rollers, and
subjected to rolling-cooling and crushed with a pulverizer to obtain carbon black
masterbatch. This is referred to as "masterbatch 1".
-Preparation of Oil Phase-
378 parts of "unmodified polyester a", 55 parts of carnauva wax and 947
parts of ethyl acetate were introduced into a reaction vessel provided with
stirrer and thermometer, and the temperature was raised to 80°C with stirring,
maintained at 80°C for 5 hours, and cooled to 30°C over 1 hour. Next, 500 parts
of "masterbatch 1" and 500 parts of ethyl acetate were introduced into the
reaction vessel and mixed for 1 hour to obtain "raw material solution 1".

1,324 parts of "raw material solution 1" were transferred to the reaction
vessel, and carbon black and wax were dispersed using a bead mill (Ultra Visco
Mill by Aimex Co., Ltd.) under the condition of liquid feed rate 1kg/hr, disk
circumferential speed 6m/sec, 0.5 mm zirconia beads packed to 80% by volume
and 3 passes.
Next, 1,324 parts of 65% ethyl acetate solution of the "unmodified
polyester a" was added and dispersed in 3 passes by the bead mill under the
aforesaid condition to obtain "pigment/wax dispersion 1".
-Emulsification-
749 parts of "pigment/wax dispersion 1", 115 parts of
"isocyanate-group-containing prepolymer 1", and 2.9 parts of "ketimine
compound 1" were placed in a reaction vessel and mixed in a TK homomixer by
Tokushu Rika Kogyo Co., Ltd. at 5,000 rpm for 1 minute. Then 1,000 parts of
"aqueous phase 1" were added to the reaction vessel and mixed in the FILLMIX
by Tokushu Kika Kogyo Co., Ltd. at a rotation speed of 5,000 rpm for 5 minutes
to obtain "emulsion slurry 1". Then, the reaction mixture was matured for 3
hours after emulsification maintaining the liquid temperature at 20°C ± 2°C.
The particle diameter immediately after emulsification was 2.5 µm, dried
products of emulsified liquid was kneaded with Labo Plastomill, and 1/2
flown-out temperature was measured, checking the progress of urea reaction.
Reaction of interest and particle diameter of emulsification were
examined and the reaction was stopped when the particle diameter reached 4

µm to 5 µm.
The "emulsion slurry 1" was placed in a reaction vessel equipped with
stirrer and thermometer, then the solvent was removed at 30°C for 8 hours to
obtain "dispersion slurry 1."
-Rinsing and Drying-
After filtering 100 parts of "dispersion slurry 1" under the reduced
pressure, rinsing and drying processes were performed by following procedures.
(1) 100 parts of ion exchange water were added to the filter cake and
mixed in a TK homomixer at a rotation speed of 12,000 rpm for 10 minutes and
filtered.
(2) 100 parts of 10% sodium hydroxide solution were added to the filter
cake of (1) and mixed in a TK homomixer at a rotation speed of 12,000 rpm for
30 minutes and filtered under the reduced pressure.
(3) 100 parts of 10% hydrochloric acid were added to the filter cake of (2)
and mixed in a TK homomixer at a rotation speed of 12,000 rpm for 10 minutes
and filtered.
(4) 300 parts of ion exchange water were added to the filter cake of (3)
and mixed in a TK homomixer at a rotation speed of 12,000 rpm for 10 minutes
and filtered twice to obtain "filter cake 1".
The "filter cake 1" was then dried in a circulating air dryer at 45°C for
48 hours, and sieved through a sieve of 75 µm mesh to obtain "toner 1".

Next, against the base particle of obtained colored powder, 100 parts of
base particle, 0.25 part of charge controlling agent (Bontron E-84 by Orient
Chemical Industries, Ltd.) were introduced to a Q-type mixer (by Mitsui
Mining Co., Ltd.) and were subjected to a mixing treatment at a turbine blade
peripheral speed of 50 m/sec. The mixing was performed 5 cycles each
including 2 minute mixing and 1 minute pause (thus, mixing time was 10
minutes in total).
This was further mixed with 0.5 part of hydrophobized silica (H2000 by
Clariant(Japan)KK). The mixing was performed at a peripheral speed of 15
m/sec and 5 cycles each including 30 second mixing and 1 minute pause to
prepare black toner (1).
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.93 and
had a spindle shape. FIG. 22 shows a SEM picture of toner.
(Example B-2)
"Toner 2" was obtained in the same way as in Example B-1, except that,
in Example B-1, "resin fine particle dispersion 2" synthesized as described below
was used in place of "resin fine particle dispersion 1", and black toner (2) was
prepared.
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.92 and
had a spindle shape. FIG. 22 shows a SEM picture of toner.

-Synthesis of Resin Fine Particle Emulsion-
lb a reaction vessel provided with stirrer and thermometer, 683 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 80 parts
of styrene, 83 parts of methacrylic acid, 110 parts of butyl acrylate, 12 parts of
butyl thioglycolate, and 1 part of ammonium persulphate were introduced, and
stirred at 400 rpm for 15 minutes to give a white emulsion. This was heated,
the temperature in the system was raised to 75°C and the reaction was
performed for 5 hours. Next, 30 parts of an aqueous solution of 1% ammonium
persulphate was added, and the reaction mixture was matured at 75°C for 5
hours to obtain an aqueous dispersion of a vinyl resin (copolymer of
styrene-methacrylic acid- butyl acrylate-sodium salt of sulfuric acid ester of
methacrylic acid ethylene oxide adduct), "resin fine particle dispersion 2".
The "resin fine particle dispersion 2" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser light
scattering technique is adopted, and the volume average particle diameter was
120 nm. After drying a part of the "resin fine particle dispersion 2", the resin
was isolated. The glass-transition temperature, Tg, of the resin was 52°C and
the average molecular mass, Mw was 300,000.
(Example B-3)
"Toner 3" was obtained in the same way as in Example B-1, except that,
in Example B-1, "resin fine particle dispersion 3" synthesized as described below

was used in place of "resin fine particle dispersion 1", and black toner (3) was
prepared.
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.91 and
had a spindle shape.
-Synthesis of Resin Fine Particle Emulsion-
lb a reaction vessel provided with stirrer and thermometer, 760 parts of
water, 14 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 103
parts of styrene, 83 parts of methacrylic acid, 90 parts of butyl acrylate, 12 parts
of butyl thioglycolate, and 1 part of ammonium persulphate were introduced,
and stirred at 400 rpm for 15 minutes to give a white emulsion. This was
heated, the temperature in the system was raised to 75°C and the reaction was
performed for 5 hours. Next, 30 parts of an aqueous solution of 1% ammonium
persulphate was added, and the reaction mixture was matured at 75°C for 5
hours to obtain an aqueous dispersion of a vinyl resin (copolymer of
styrene-methacrylic acid- butyl acrylate-sodium salt of sulfuric acid ester of
methacrylic acid ethylene oxide adduct), "resin fine particle dispersion 3".
The "resin fine particle dispersion 3" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser light
scattering technique is adopted, and the volume average particle diameter was
60 nm. After drying a part of the "resin fine particle dispersion 3", the resin

was isolated. The glass-transition temperature, Tg of the resin was 63°C and
the average molecular mass, Mw was 150,000.
(Example B-4)
"Toner 4" was obtained in the same way as in Example B-1, except that,
in Example B-1, "resin fine particle dispersion 4" synthesized as described below
was used in place of "resin fine particle dispersion 1", and black toner (4) was
prepared.
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.95 and
had a spindle shape.
-Synthesis of Resin Fine Particle Emulsion-
To a reaction vessel provided with stirrer and thermometer, 683 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 78 parts
of styrene, 83 parts of methacrylic acid, 105 parts of butyl acrylate, 2 parts of
butyl thioglycolate, and 1 part of ammonium persulphate were introduced, and
stirred at 400 rpm for 15 minutes to give a white emulsion. This was heated,
the temperature in the system was raised to 75°C and the reaction was
performed for 5 hours. Next, 30 parts of an aqueous solution of 1% ammonium
persulphate was added, and the reaction mixture was matured at 75°C for 5
hours to obtain an aqueous dispersion of a vinyl resin (copolymer of
styrene-methacrylic acid- butyl acrylatesodium salt of sulfuric acid ester of

methacrylic acid ethylene oxide adduct), "resin fine particle dispersion 4".
The "resin fine particle dispersion 4" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser fight
scattering technique is adopted, and the volume average particle diameter was
30 µm.
After drying a part of the "resin fine particle dispersion 4", the resin was
isolated. The glass-transition temperature, Tg of the resin was 56°C and the
average molecular mass, Mw was 500,000.
(Example B-5)
'"Toner 5" was obtained in the same way as in Example B-4, except that,
in Example B-4, "unmodified polyester b" synthesized as described below was
used in place of "unmodified polyester a", and black toner (5) was prepared.
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.93 and
had a spindle shape.
-Production of Unmodified Polyester
In a reaction vessel equipped with condenser tube, stirrer, and nitrogen
inlet tube, 196 parts of bisphenol A propylene oxide dimolar adduct, 553 parts of
bisphenol A ethylene oxide dimolar adduct, 210 parts of terephthalic acid, 79
parts of adipic acid and 2 parts of dibutyl tin oxide were placed, and the reaction
was performed under normal pressure at 230°C for 8 hours. Further, reaction
was performed under a reduced pressure of 10mmHg to 15mmHg for 5 hours.

Then 26 parts of trimellitic anhydride was placed in the reaction vessel, and the
reaction was performed under normal pressure at 180°C for 2 hours to obtain
"unmodified polyester b".
The "unmodified polyester b" had a number average molecular mass
(Mn) of 6,200, average molecular mass (Mw) of 36,000, glass-transition
temperature (Tg) 33°C, acid value of 15.
(Comparative Example B-1)
Initially, to 709 g of ion exchange water, 451 g of 0.1MNa3PO4 aqueous
solution was introduced and heated to 60°C, and then stirred at 12,000 rpm
using TK homomixer. To the mixture, 68 g of 1.0M-CaCl2 aqueous solution was
gradually added to obtain an aqueous medium containing Ca3(PO4)2.
Next, 170 g of styrene, 30 g of 2-ethylhexyl acrylate, 3.4 g of ethylene
grycol diacrylate, 10 g of REGAL 400R, 60 g of paraffin wax (s.p. 70°C), 5 g of
drtert-butyl salicylic acid metal compound, and 10 g of styrene-methacrylic acid
copolymer (Average Molecular Mass, (Mw): 50,000; Acid Value: 20 mgKOH/g)
were introduced into TK homomixer and was heated to 60°C, uniformly
dissolved and dispersed at 12,000 rpm. To the mixture were further added and
dissolved 10 g of 2,2'-azobis(2,4-dimethyl valeronitrile) as a polymerization
initiator, and thereby prepared polymerizable monomers.
To the aqueous medium were introduced the polymerizable monomers,
were mixed in a TK homomixer at 10,000 rpm for 20 minutes in a nitrogen flow,
at 60°C to form particles of the polymerizable monomers. Then, the granulated

monomers were subjected to a reaction for 3 hours at 60°C while stirring with a
paddle-stirring blade. Thereafter, the temperature of the liquid was raised to
80°C and subjected to a further reaction for 10 hours.
After polymerization reaction, the solution was cooled, and hydrochloric
acid was added so as to dissolve calcium phosphate therein. The solution was
filtered, washed and dried to obtain "comparative toner 1". To the "comparative
toner 1" additives were mixed as in Example B-1 to prepare comparative toner
(1).
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.97 and
had a spherical shape.
(Comparative Example B2)
-Preparation of aqueous wax particle dispersion-
In a 1000 ml four necked flask equipped with stirrer, thermometer,
nitrogen inlet tube and condenser tube, 500 ml of deaerated distilled water, 28.5
g of Newcol 565C (by Japan Emulsifier Inc.) and 185.5 g of candelilla wax No. 1
(by Noda Wax Co., Ltd.) were placed. The contents in the flask were then
heated with stirring under a nitrogen gas flow and the temperature was raised.
At the time of an inside temperature of 85°C, to the mixtue 5 N sodium
hydroxide solution was added and the temperature was raised to 75° C. Then,
the mixture was kept with heating and stirring at 75° C for 1 hour and then
cooled to room temperature to obtain "aqueous wax particle dispersion 1".

-Preparation of aqueous colorant dispersion-
100 g of carbon black (Trade name: Mogal L by Cabot Corporation) and
25 g of sodium dodecylsulfate were added to 540 ml of distilled water and the
mixture was stirred sufficiently and then dispersed using a pressurizing
disperser (MINI-LAB manufactured by Raney Inc.) to obtain "aqueous colorant
dispersion 1".
-Preparation of aqueous dispersion of high molecular mass binder fine particle -
In a 1 L four necked flask equipped with stirrer, condenser tube,
thermometer, and nitrogen inlet tube, 480 ml of distilled water, 0.6 g of sodium
dodecylsulfate, 106.4 g of styrene, 43.2 g of n-butyl acrylate, and 10.4 g of
methacrylic acid were placed and heated with stirring under a nitrogen gas flow
to 70°C, to which an aqueous solution of initiator containing 2.1 g of potassium
sulfate dissolved in 120 ml of distilled water was added. The mixture was
stirred under a nitrogen gas flow at 70°C for 3 hours. After completion of the
polymerization, the reaction mixture was cooled to room temperature to obtain
"aqueous dispersion of high molecular mass binder fine particle 1".
-Preparation of aqueous dispersion of low molecular mass binder fine particle -
In a 5 L four necked flask equipped with stirrer, condenser tube,
thermometer, and nitrogen inlet tube, 2400 ml of distilled water, 2.8 g of sodium
dodecylsulfate, 620 g of styrene, 128 g of n-butyl acrylate, 52 g of methacrylic
acid, and 27.4 g of tert-dodecylmercaptan were placed and heated with stirring
under a nitrogen gas flow to 70°C, to which an aqueous solution of initiator

containing 11.2 g of potassium sulfate dissolved in 600 ml of distilled water was
added. The mixture was stirred under a nitrogen gas flow at 70°C for 3 hours.
After completion of the polymerization, the reaction mixture was cooled to room
temperature to obtain "aqueous dispersion of low molecular mass binder fine
particle 2".
In a 1 L separable flask equipped with stirrer, condenser tube, and
thermometer, 47.6 g of the "aqueous dispersion of high molecular mass binder
fine particle 1", 190.5 g of the "aqueous dispersion of low molecular mass binder
fine particle 2", 7.7 g of the "aqueous wax particle dispersion 1", 26.7 g of the
"aqueous colorant dispersion I and 252.5 ml of distilled water were placed and
mixed with stirring, to which a 5 N sodium hydroxide solution was added to
adjust the pH of the mixture to 9.5. With stirring, aqueous sodium chloride
solution containing 50 g of sodium chloride dissolved in 600 ml of distilled water,
77 ml of isopropanol and an aqueous surfactant solution containing 10 mg of
Fluorad FC-170C (by Sumitomo 3M Inc.: fluorine containing nonionic
surfactant) dissolved in 10 ml of distilled water were successively added to the
flask, inside temperature was raised to 85°C, reacted for 6 hours, and cooled to
room temperature. This reaction mixture was mixed with 5 N sodium
hydroxide solution so that the pH thereof was adjusted at 13, and then the
mixture was filtered. Further, the solids were resuspended in distilled water.
After washing by the repeating filtration and resuspension, the solids were dried
to obtain "comparative toner 2. To the "comparative toner 2" additives were

mixed as in Example B-1 to prepare comparative toner (2).
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.96 and
had a spindle shape.
(Comparative Example B-3)
"Comparative toner 3" was obtained in the same way as in Example Bl
except that, in Example B-1, "resin fine particle dispersion 6" synthesized as
described below was used in place of "resin fine particle dispersion 1". To the
"comparative toner 3" additives were mixed as in Example B-1 to prepare
comparative toner (3).
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.92 and
had a spindle shape.
-Synthesis of Resin Fine Particle Emulsion-
To a reaction vessel provided with stirrer and thermometer, 683 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 138
parts of styrene, 138 parts of methacrylic acid, and 1 part of ammonium
persulphate were introduced, and stirred at 400 rpm for 15 minutes to give a
white emulsion. This was heated, the temperature in the system was raised to
75°C and the reaction was performed for 5 hours. Next, 30 parts of an aqueous
solution of 1% ammonium persulphate was added, and the reaction mixture was

matured at 75°C for 5 hours to obtain an aqueous dispersion of a vinyl resin
(copolymer of styrene-methacrylic acid-sodium salt of sulfuric acid ester of
methacryhc acid ethylene oxide adduct), "resin fine particle dispersion 6".
The "resin fine particle dispersion 6" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser light
scattering technique is adopted, and the volume average particle diameter was
140 nm. After drying a part of the "resin fine particle dispersion 6", the resin
was isolated. The glass-transition temperature, Tg of the resin was 156°C and
the average molecular mass, Mw was 400,000.
(Comparative Example B-4)
"Comparative toner 4" was obtained in the same way as in Example B-1
except that, in Example B-1, "resin fine particle dispersion 7" synthesized as
described below was used in place of "resin fine particle dispersion 1".
To 100 parts of the obtained toner 0.7 parts of hydrophobized silica and
0.3 parts of hydrophobized titanium oxide were mixed in HENSCHEL MIXER
to prepare comparative toner (4).
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.94 and
had a spindle shape.
-Production of resin fine particle-
To a reaction vessel provided with stirrer and thermometer, 683 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene

oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 63 parts
of styrene, 83 parts of methacrylic acid, 130 parts of butyl acrylate, 12 parts of
butyl thioglycolate, and 1 part of ammonium persulphate were introduced, and
stirred at 400 rpm for 15 minutes to give a white emulsion. This was heated,
the temperature in the system was raised to 75°C and the reaction was
performed for 5 hours. Next, 30 parts of an aqueous solution of 1% ammonium
persulphate was added, and the reaction mixture was matured at 75°C for 5
hours to obtain an aqueous dispersion of a vinyl resin (copolymer of
styrene-methacrylic acid- butyl acrylate-sodium salt of sulfuric acid ester of
methacrylic acid ethylene oxide adduct), "resin fine particle dispersion 7".
The "resin fine particle dispersion 7" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser light
scattering technique is adopted, and the volume average particle diameter was
130 nm. After drying a part of the "resin fine particle dispersion 7", the resin
was isolated. The glass-transition temperature, Tg of the resin was 45°C and
the average molecular mass, Mw was 50,000.
(Comparative Example B-5)
-Production of resin fine particle-
To a reaction vessel provided with stirrer and thermometer, 683 parts of
water, 11 parts of sodium salt of sulfuric acid ester of methacrylic acid ethylene
oxide adduct (ELEMINOL RS-30 by Sanyo Chemical Industries, Ltd.), 83 parts
of styrene, 83 parts of methacrylic acid, 110 parts of butyl acrylate, and 1 part of

ammonium persulphate were introduced, and stirred at 400 rpm for 15 minutes
to give a white emulsion. This was heated, the temperature in the system was
raised to 75°C and the reaction was performed for 5 hours. Next, 30 parts of an
aqueous solution of 1% ammonium persulphate was added, and the reaction
mixture was matured at 75°C for 5 hours to obtain an aqueous dispersion of a
vinyl resin (copolymer of styrene-methacrylic acid- butyl acrylate-sodium salt of
sulfuric acid ester of methacrylic acid ethylene oxide adduct), "resin fine particle
dispersion 8".
The "resin fine particle dispersion 8" was measured by the particle size
distribution measuring apparatus (LA-920 by Horiba Ltd.) in which laser light
scattering technique is adopted, and the volume average particle diameter was
80 nm. After drying a part of the "resin fine particle dispersion 8", the resin
was isolated. The glass-transition temperature, Tg of the resin was 59°C and
the average molecular mass, Mw was 150,000.
-Production of Prepolymer-
In a reaction vessel equipped with condenser tube, stirrer, and nitrogen
inlet tube, 724 parts of bisphenol A ethyleneoxide dimole adduct, 276 parts of
isophthalic acid, and 2 parts of dibutyl tin oxide were placed, and the reaction
was performed under normal pressure at 230°C for 8 hours. Further, the
reaction was performed with dehydrating under a reduced pressure of 10
mmHg to 15 mmHg for 5 hours and then cooled to 160°C. To this, 32 parts of
phthalic anhydride was added, and allowed to react for 2 hours, To this, 32

parts of phthalic anhydride was added, and allowed to react for 2 hours. Next,
this was cooled to 80°C and reacted with 188 parts of isophorone diisocyanate in
ethyl acetate for 2 hours to obtain "comparative isocyanate-group containing
prepolymer 3".
-Production of Unmodified Polyester
In the same way as described above, 724 parts of bisphenol A
ethyleneoxide oxide dimolar adduct, 138 parts of terephthalic acid, and 138
parts of isophthalic acid were subjected to polycondensation under normal
pressure at 230°C for 6 hours. Thereafter, reaction was performed with
dehydrating under a reduced pressure of 10 mmHg to 15 mmHg for 5 hours to
obtain "comparative unmodified polyester 3".
In a beaker, 15.4 parts of "comparative isocyanate-group containing
prepolymer 3", 64 parts of "comparative unmodified polyester 3", and 78.6 parts
of ethyl acetate were placed and dissolved with stirring. Next, 20 parts of
pentaerythritol tetrabehenate and 10 parts of carbon (REGAL 400R by Cabot
Corporation) were placed, mixed in a TK type homomixer at 12,000 rpm at 60°C,
and uniformly dissolved and dispersed.
Lastly, 2.7 parts of "ketimine compound 1" was added and dissolved.
This is referred to as "comparative toner material solution (1)". In a beaker,
706 parts of ion exchange water, 294 parts of hydroxyl apatite 10% suspension
(SUPERTITE 10 by Nippon Chemical Industrial Co., Ltd.), and 0.2 parts of
sodium dodecylbenzenesulfonate were placed and uniformly dissolved.

Next, temperature was raised to 60°C, mixed in a TK type homomixer
at 12,000 rpm, and the above-mentioned "comparative toner material solution
(1)" was introduced and mixed for 10 minutes. Thereafter, this mixture was
transferred to a flask equipped with stirring bar and temperature indicator, and
temperature was raised to 55°C. While effecting the ureα-introducing reaction,
the solvent was removed under 25 mmHg to 50 mmHg, filtered, washed, dried,
and then classified by a wind force. Next, to 100 parts of toner particle, 0.5 part
of colloidal silica (Aerosil R972: by Nippon Aerosil Co., Ltd.) was mixed in a
sample mill to prepare "comparative toner 5".
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.95 and
had a spindle shape.
(Comparative Example B-6)
Initially, with 2 parts of dibutyltin oxide as a catalyst, 325 parts of
bisphenol A ethyleneoxide oxide dimolar adduct and 155 parts of terephthalic
acid were subjected to polycondensation to obtain "comparative toner binder 4".
The "comparative toner binder 4" had a glass-transition temperature (Tg) of
61°C.
Next, in a beaker, 100 parts of "comparative toner binder 4", 200 parts
of ethyl acetate, and 8 parts of carbon black (#44 by Mitsubishi Chemical
Corporation), 5 parts of rice wax used in Example B-1 were placed, mixed in a
TK type homomixer at 12,000 rpm at 50°C, and uniformly dissolved and

dispersed. Next, toner was prepared in the same way as in Example B-1 to
obtain "comparative toner 6" having a volume average particle diameter of 4.5 µm.
The properties and evaluation results of thus obtained toner are shown
in Tables 4 and 5, respectively. The obtained toner had a circularity of 0.97 and
had a spherical shape.

1. Kneading test method with Labo Plastomill
(i) Labo Plastomill (Type 30C150, by Toyo Seiki Seisakusho, Ltd.)
(ii) Small grinder (Oster mixer)
(iii) Test sieve
Gv) Work procedure
Toner is melt kneaded using Labo Plastomill and kneaded mixture is
crushed with Oster mixer and the material remaining on a 180 µm mesh is used
as a sample.

Mixer : R60
Temperature : 130°C
Time : 15 minutes
Sample amount : 45 g
Mixer rotation number: 50 rpm


Next, when each of the obtained toners of Examples and Comparative
Examples was evaluated for image quality, etc. of a reproduced image,
performance of toner was evaluated as a two-component developer.
The carrier for use in the two-component developer was ferrite carrier
having an average particle diameter of 35 µm, coated with silicone resin with an
average thickness of 0.5 µm and 7 parts by mass of toner was uniformly mixed
to 100 parts by mass of the carrier and charged by a tubular mixer of which the
container is rolled for agitation to prepare developer.
The carrier was prepared as follows. 5,000 parts of Mn ferrite particle
(mass average particle diameter: 35 µm) was used as a core material and a
coating solution was prepared by dispersing 450 parts of toluene, 450 parts of
silicone resin SR2400 (by Dow Corning Toray Silicone Co., Ltd., non-volatile
portion 50%), 10 parts of aminosilane SH6020 (by Dow Corning Toray Silicone
Co., Ltd.) and 10 parts of carbon black, that are coating material, were dispersed
with a stirrer for 10 minutes to prepare a coating liquid. The core material and
the coating liquid were poured into a coating apparatus equipped with a
rotating base plate disk and stirring blades in a fluidized bed, in which coating is
conducted while forming a whirling flow, and the coating liquid was applied onto
the core material. The coated material was then baked in an electric oven at
250°C for 2 hours to prepare the above-mentioned carrier.


2.1/2 flown-out temperature by a flow tester
As a flow tester, capillary type flow tester CFT500D, by Shimadzu
Corporation was used. FIGS. 18A and 18B shows a flow curve of this flow
tester, and from this, each temperature can be read. In FIGS. 18A and 18B, Ts
represents softening temperature and Tfb represents flow beginning
temperature, and melting temperature according to 1/2 method represents 1/2
flown-out temperature by a flow tester

Load: 5 kg/cm2, Temperature rising rate: 3.0°C/min, Die diameter: 1.00
mm, Die length: 10.0 mm
3. Method for measuring THF insoluble content
About 1.0 g (A) of resin or toner is weighed. To this, about 50 g of
tetrahydrofuran (THF) is added and is left to stand at 20°C for 24 hours. This
is separated by centrifugation and then filtered using filter paper for
quantitative measurement. The solvent component of obtained filtrate is
vacuum-dried and only resin component is weighed to measure the residual
amount (B). This residual amount is THF soluble component.
The THF insoluble component (%) is calculated according to the
following formula:
THF insoluble component (%) = (A-B)/A



Next, following evaluation was carried out using each of obtained toners.
Image evaluation was carried out using the two-component developer prepared
as described below and image evaluation of 100,000 sheets was carried out
using an image forming apparatus (imagio NEO450 by Ricoh Company, Ltd.
-Method for preparing two-component developer-
50 parts of each toner and 950 parts of a silicone-resin coated carrier
(Silicone resin, KR-250, core material carrier 70 µm, by Shin-Etsu Chemical Co.,
Ltd.) were mixed and completely shaken up to prepare a two-component
developer.

A modified image forming apparatus (Copier MF-200 by Ricoh Company,
Ltd.), in which a Teflon (Trademark) roller was used as a fixing roller and the
fixing section was modified, was used, type 6200 paper by Ricoh Company, Ltd.
was set to this apparatus, and copying test was carried out. The lowest fixing
temperature used herein is the temperature of the fixing roll at which the
residual rate of the image density was 70% or more when the fixed image was
rubbed with a pat.

Image fixation was evaluated in the same way as in the above-described
lowest fixing temperature. Occurrence of hot offset with respect to the fixed
image was determined with naked eyes. The hot offset generating
temperature used herein is the temperature of the fixing roll at which hot offset

occurred.

Remelting means such a phenomenon that the toner, adhered to a
fixing roller at the time of fixing, is transferred to a pressure roller and the
toner is collected by a cleaning roller; however, the collected adhered toner
starts to melt again due to the heat of a heating roller, and the remelted toner
is transferred to a pressure roller, resulting in adhesion to or contamination of
images.
As the test method, continuous running of remelting is carried out in
which toner is allowed to adhere to a cleaning roller and whether or not the
toner has remelted is observed. Images were produced according to the
following condition and the number of sheets when the remelting occurred, that
is, the number when images start to be smeared, was observed.

Copier: imagio Neo 451 by Ricoh Company, Ltd.
Fixing unit for evaluation: fixing device for imagio Neo 451 by Ricoh
Company, Ltd. (Pressure diameter φ30)
Run mode: 1 to 15, interval 30 S, 6% chart, 15K/day

Measuring instrument: Penetrometer (Nikka Engineering)
Tapping machine
30 mL screw vial

Storage: Thermostat bath
Method: (1) 10.8 g of toner is placed in a screw vial
(2) The toner of (1) is subjected to a tapping machine at 150 rotation/1
minute 35 seconds
(3) Stored gently in a thermostat bath at predetermined temperature,
50°C, and for 24 hours.
(4) After 24 hours, allowed to stand for 2 hours.
(5) Allow a needle to drop from a penetrometer and the penetration is
measured
[Evaluation Standards]
A :(Small circle): penetration of 15 mm or more
B: (Delta): penetration of 10 mm to 14 mm
C: penetration of 9 mm or less

Bulk density is measured and is used as an index of flowability of toner.
Bulk density was measured using Powder Tester by Hosokawa Micron
Corporation. Greater the bulk density, the better is the flowability.
1. Construction of measuring instrument
(1) Graduated cylinder (50 ml (±0.25 ml TC20°C))
(2) Stopwatch
(3) Electronic balance (Accuracy of measurement: Within 0.1 g)
2. Measurement procedure

(1) Measure a predetermined amount 1 of the sample using an electronic
balance
(2) Measure the mass of graduated cylinder and read to the last digit, or not
rounding the last digit
(3) Start the stopwatch immediately after the sample has been placed, let it
alone for 10 minutes to 11 minutes. During this period, be careful not to give
vibration and/or impact.
(4) Read the volume of powder using the markings on the graduated cylinder
to 0.5 ml
(5) Measure the mass of sample and graduated cylinder, and read to the last
digit, or not rounding the last digit
(6) Calculation is carried out as follows.
Formula 1
Bulk density (g/cm3) = {(mass of sample and graduated cylinder) -
(mass of graduated cylinder)} / volume of powder
[Evaluation Standards]
A: (Small circle)- 0.40 g/cm3 or more
B:(Delta): 0.35 to 0.39 g/cm3
C: 0.30 g/cm3 or less

As a fixing roller, one in a modified image forming apparatus (Copier
imagio NEO450 by Ricoh Company, Ltd.), in which a fixing section was

modified as described below, was used. Ttype 6200 paper by Ricoh Company,
Ltd. was set to this apparatus, and copying test was carried out. The fixing
unit used in this apparatus had a fixing roller of which metal cylinder was
made of Fe material and had a thickness of 0.34 mm, and the surface pressure
was set to 1.0x105Pa.

Image density was measured using Macbeth reflection densitometer,
determined as relative density by correcting with standard one, and evaluated
based on the following standard. 5 mm to 10 mm circle at solid parts was
measured.
[Image density evaluation standard]
A: (Small circle): 1.5 or more
B: (Delta): not less than 1.4 to less than 1.5
C: less than 1.4

Pattern images each comprising five thin lines having an equal width
and an equal spacing were formed with different pitches of 2.8 patterns, 3.2
patterns, 3.6 patterns, 4.0 patterns, 4.5 patterns, 5.0 patterns, 5.6 patterns, 6.3
patterns, 7.1 patterns, and 8.0 patterns, respectively per mm, as an original.
The original image was reproduced and obtained copied image was observed
with a magnifying glass at a magnification of 5 times, and image resolution was
determined based on the number of patterns (pattern/mm) where thin fines are

clearly separated to each other.
[Image resolution evaluation standard]
A: (Small circle): 6.3 patterns/mm or more
B: (Delta): 5.0 patterns/mm to 5.6 patterns/mm
C: 4.5 p atterns/mm



[Evaluation Standards]
A: (Small circle): Satisfactory
B:(Delta): Somewhat problematic
C: Not acceptable
In any of Examples B-l to B-5, fixing at low temperatures could be
achieved, and smear due to remelting of toner from a fixing cleaning roller was
not observed.
In Comparative Example B-1, the toner did not have resin fine particles,
had a large particle diameter and poor fixing property at low temperatures.
The toner had decreased flowability because the amount of particles of 3 µm or
less was large.
In Comparative Example B-2, the toner did not have resin fine particles
and had deteriorated hot offset property, and smear due to remelting of toner
from a fixing cleaning roller was observed.
In Comparative Example B-3, lower limit of fixing was high because the
glass-transition temperature (Tg) of resin fine particles was high.
In Comparative Example B-4, anti-heat preservability was deteriorated
because the glass-transition temperature (Tg) of resin fine particles was low.
In Comparative Example B-5, 1/2 flown-out temperature after
mastication was low, and thus smear due to remelting of toner from a fixing
cleaning roller was observed.
In Comparative Example B-6, the toner did not have resin fine particles,

had a high glass-transition temperature (Tg), and thus had deteriorated fixing
property at low temperatures. The toner also had deteriorated hot offset
property.
Industrial Applicability
The toner of the invention is used in a developer for fixing a latent
electrostatic image of electrophotography, electrostatic recording, electrostatic
printing, and the like
The toner of the invention is also used in a developer, toner container,
and process cartridge for use in a copier, laser printer, plain paper fax machine,
etc. employing a direct or indirect electrographic developing method.
In addition, the image forming apparatus and image forming method
using the toner of the invention is used for a full-color copier, full-color laser
printer, full-color plain paper fax machine, etc. employing a direct or indirect
electrographic multicolor developing method.

We Claim :
1. A toner comprising a toner material,
wherein the toner satisfies the following formula:

where ΔTm represents Tma - Tmb, Tma (°C) is 1/2 flown-out temperature of the toner by a
capillary type flow tester, and Tmb (°C) is 1/2 flown-out temperature of a melt kneaded mixture of the
toner by the capillary type flow tester, and
wherein Tma is from 130°C to 200°C;
the toner has a core/shell structure; and
the 1/2 flown out temperatures Tma and Tmb represent the temperature at which a 1/2 of the
toner and a 1/2 of the melt kneaded mixture of the toner flow out, respectively, and that they are
measured at conditions with a load of 30 kg, die diameter of 1 mm and a temperature rising rate of 3°C/
min.
2. The toner as claimed in claim 1, wherein the toner satisfies the following formula:

where ΔTm represents Tma - Tmb, and
wherein Tma is from 145°C to 180°C.
3. The toner as claimed in any one of claims 1 or 2, wherein a tetrahydrofuran (THF) insoluble
content (gel content) in the toner is from 10% by mass to 55% by mass.

4. The toner as claimed in any one of claims 1 to 3, wherein the molecular mass distribution of the
toner measured by gel permeation chromatography (GPC) has at least one peak in a molecular mass
region of 5,000 to 25,000.
5. The toner as claimed in any one of claims 1 to 4, wherein the toner has a glass-transition
temperature, Tg, of 50°C to 70°C,
6. The toner as claimed in any one of claims 1 to 5, wherein the average circularity of the toner is
0.94 to 0.99.
7. The toner as claimed in any one of claims 1 to 6, wherein the volume average particle diameter
(Dv) of the toner is 3.0um to 7.0um, and the ratio of the volume average particle diameter (Dv) to the
number average particle diameter (Dn), Dv/Dn, is 1.25 or less.
8. The toner as claimed in any one of claims 1 to 7, wherein the toner is obtained by:
at least one of dissolving and dispersing the toner material including an active hydrogen group-
containing compound and a polymer that is reactive with the active hydrogen group containing
compound in an organic solvent to form a toner solution;
at least one of emulsifying and dispersing the toner solution in an aqueous medium containing
resin fine particles to prepare a dispersion;
reacting the active hydrogen group containing compound with the polymer that is reactive with
the active hydrogen group containing compound in the aqueous medium to granulate adhesive base
materials; and

9. The toner as claimed in claim 8, wherein the adhesive base material comprises a polyester
resin.
10. The toner as claimed in claim 9, wherein the acid value of the polyester resin is from 15
mgKOH/g to 45 mgKOH/g.
11. The toner as claimed in one of claims 9 and 10, wherein the polyester resin comprises a
tetrahydrofuran soluble component and the tetrahydrofuran soluble component has a molecular mass
distribution such that a main peak is present in a molecular mass region of 2,500 to 10,000 and that the
number average molecular mass thereof is in the range of 1,500 to 15,000.
12. A two-component developer comprising:
a toner as claimed in any one of claims 1 to 11; and
a carrier.
13. An image forming apparatus comprising:
a latent electrostatic image bearing member;
a latent electrostatic image forming unit configured to form an latent electrostatic image on the
latent electrostatic image bearing member;
a developing unit configured to develop the latent electrostatic image and comprising the toner

as claimed in claim 1 to form a visible image;
a transferring unit configured to transfer the visible image onto a recording medium; and
a fixing unit configured to fix the transferred image on the recording medium.
14. The image forming apparatus as claimed in claim 13, wherein the latent electrostatic image
bearing member comprises an amorphous silicon.
15. The image forming apparatus as claimed in one of claims 13 and 14, wherein the fixing unit is a
heat fixing unit which fixes a toner image on a recording medium while the recording medium is
passed between a heating member and a pressure member and is transported.
16. The image forming apparatus as claimed in claim 15, wherein the heat fixing unit comprises a
cleaning member which removes a toner adhered to at least one of the heating member and the pressure
member, and
wherein a surface pressure (roller load/contact area) applied between the heating member and
the pressure member is 1.5x103Pa or less.
17. The image forming apparatus as claimed in one of claims 13 and 14, wherein the fixing unit
comprises:
a heating member equipped with a heat generator;
a film which contacts with the heating member; and
a pressure member which makes pressure contact with the heating member via the film,

wherein the recording medium, on which an unfixed image is formed after electrostatic transfer,
is passed between the film and the pressure member to thereby heat and fix the unfixed image.
18. The image forming apparatus as claimed in one of claims 13 and 14, wherein the fixing unit
comprises:
a heating roller;
a fixing roller arranged parallel to the heating roller;
an endless belt-like toner heating medium; and
a pressure roller,
wherein the heating roller comprises a magnetic metal and is heated by electromagnetic
induction; the toner heating medium is spanned over the heating roller and the fixing roller, is heated
by the heating roller, and is rotated by these rollers; the pressure roller is brought into pressure contact
with the fixing roller via the toner heating medium and rolls in the forward direction towards the toner
heating medium to form a fixing nip portion, and
wherein a recording medium, on which an unfixed image is formed after electrostatic transfer, is
passed between the toner heating medium and the pressure member to thereby heat and fix the unfixed
image.
19. An image forming method comprising:
forming a latent electrostatic image on a latent electrostatic image bearing member;
developing the latent electrostatic image using the toner as claimed in claim 1 to form a visible
image;
transferring the visible image onto a recording medium; and

fixing the transferred image on the recording medium.
20. The image forming method as claimed in claim 19, wherein a charging member is contacted to
the latent electrostatic image bearing member and a voltage is applied to the charging member to
charge the latent electrostatic image bearing member.
21. The image forming method as claimed in one of claims 19 and 20, wherein, when developing
the latent electrostatic image on the latent electrostatic image bearing member, an alternate electric
filed is applied to a charging member.

ABSTRACT
TONER, IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD
The present invention relates to a toner comprising a toner material, wherein the toner satisfies the
following formula: 5 °C ≤ ΔTm ≤ 20 °C; where ΔTm represents Tma - Tmb, Tma (°C) is 1/2 flown-out
temperature of the toner by a capillary type flow tester, and Tmb (°C) is 1/2 flown-out temperature of a
melt kneaded mixture of the toner by the capillary type flow tester, and wherein Tma is from 130°C to
200°C; the toner has a core-shell structure; and the 1/2 flown out temperatures Tma and Tmb represent
the temperature at which a 1/2 of the toner and a 1/2 of the melt kneaded mixture of the toner flow out,
respectively, and that they are measured at conditions with a load of 30 kg, die diameter of 1 mm and a
temperature rising rate of 3°C/min. The invention also discloses an image forming apparatus and an
image forming method using the above toner.
FIG. 22

Documents:

00854-kolnp-2006 assignment.pdf

00854-kolnp-2006 drawings.pdf

00854-kolnp-2006-abstract.pdf

00854-kolnp-2006-claims.pdf

00854-kolnp-2006-correspondence(other).pdf

00854-kolnp-2006-description(complete).pdf

00854-kolnp-2006-form 1.pdf

00854-kolnp-2006-form 3.pdf

00854-kolnp-2006-form 5.pdf

00854-kolnp-2006-international publication.pdf

00854-kolnp-2006-international search report.pdf

00854-kolnp-2006-other document.pdf

00854-kolnp-2006-other pct document.pdf

00854-kolnp-2006-pct prority notification.pdf

00854-kolnp-2006-priority document.pdf

854-KOLNP-2006-(09-02-2012)-AMANDED CLAIMS.pdf

854-KOLNP-2006-(09-02-2012)-CORRESPONDENCE.pdf

854-KOLNP-2006-(21-02-2012)-CORRESPONDENCE.pdf

854-KOLNP-2006-ABSTRACT 1.1.pdf

854-KOLNP-2006-AMANDED CLAIMS-1.1.pdf

854-KOLNP-2006-AMANDED CLAIMS.pdf

854-KOLNP-2006-ASSIGNMENT.pdf

854-KOLNP-2006-CORRESPONDENCE 1.5.pdf

854-KOLNP-2006-CORRESPONDENCE-1.1.pdf

854-KOLNP-2006-CORRESPONDENCE-1.2.pdf

854-KOLNP-2006-CORRESPONDENCE-1.3.pdf

854-KOLNP-2006-CORRESPONDENCE-1.4.pdf

854-KOLNP-2006-CORRESPONDENCE.pdf

854-kolnp-2006-description (complete) 1.1.pdf

854-KOLNP-2006-DRAWINGS 1.1.pdf

854-KOLNP-2006-EXAMINATION REPORT REPLY RECIEVED 1.1.pdf

854-KOLNP-2006-EXAMINATION REPORT.pdf

854-KOLNP-2006-FORM 1 1.1.pdf

854-KOLNP-2006-FORM 18.pdf

854-KOLNP-2006-FORM 2 1.1.pdf

854-KOLNP-2006-FORM 2.pdf

854-KOLNP-2006-FORM 3 1.1.pdf

854-KOLNP-2006-FORM 3 1.2.pdf

854-KOLNP-2006-FORM 5.pdf

854-KOLNP-2006-GRANTED-ABSTRACT.pdf

854-KOLNP-2006-GRANTED-CLAIMS.pdf

854-KOLNP-2006-GRANTED-DESCRIPTION (COMPLETE).pdf

854-KOLNP-2006-GRANTED-DRAWINGS.pdf

854-KOLNP-2006-GRANTED-FORM 1.pdf

854-KOLNP-2006-GRANTED-FORM 2.pdf

854-KOLNP-2006-GRANTED-SPECIFICATION.pdf

854-KOLNP-2006-OTHERS 1.1.pdf

854-KOLNP-2006-OTHERS 1.2.pdf

854-KOLNP-2006-PA.pdf

854-KOLNP-2006-PETITION UNDER RULE 137.pdf

854-KOLNP-2006-REPLY TO EXAMINATION REPORT.pdf

abstract-00854-kolnp-2006.jpg


Patent Number 252929
Indian Patent Application Number 854/KOLNP/2006
PG Journal Number 24/2012
Publication Date 15-Jun-2012
Grant Date 11-Jun-2012
Date of Filing 06-Apr-2006
Name of Patentee RICOH COMPANY, LTD.
Applicant Address 3-6 NAKAMAGOME 1-CHOME, OHTA-KU, TOKYO
Inventors:
# Inventor's Name Inventor's Address
1 NAKAYAMA SHINYA GRAND RIVER AVENUE 201, 1714-10, AZA HINGOUCHI, SHIMOKANUKI, NUMAZU-SHI, SHIZOUKA 410-0822
2 IWAMOTO YASUAKI 14-18, ICHIMICHI-CHO, NUMAZU-SHI, SHIZUOKA 410-0866
3 ASAHINA YASUO INAMO HEIGHTS 205, 14-36, WAKABE-CHO, NUMAZO-SHI, SHIZOUKA 410-0059
4 KOTSUGAI AKIHIRO 3135-15, SHIMOKANUKIZENDATU, NUMAZU-SHI, SHIZOUKA 410-0822
5 ISHII MASAYUKI PARK HILLS OOKA 205, 995-1, OOKA, NUMAZU-SHI, SHIZUOKA 410-0022
6 UCHINOKURA OSAMU SUNRISE OTSUKA 103, 1069-1, OTSUKA, NUMAZU-SHI, SHIZUOKA 410-0306
7 NAKAJIMA HISASHI CORPO UEHARA, 1-17-1, NUMAKITA-CHO, NUMAZU-SHI, SHIZUOKA 410-0058
8 ICHIKAWA TOMOYUKI CORPO SUGIMOTO 101, 19-14, TAKAZAWA-CHO, NUMAZU-SHI, SHIZUOKA 410-0057
9 UTSUMI TOMOKO 2349, KADOSA WABASHI, EBINA-SHI, KANAGAWA 243-0426
10 SAKATA KOICHI TAKASHIMAHONCHO M'S 503, 2-21, TAKASHIMAHONCHO, NUMAZU-SHI, SHIZUOKA 410-0055
11 SUGIURA HIDEKI 837-16, MIYAJIMA, FUJI-SHI, SHIZUOKA 416-0945
12 EMOTO SHIGERU 1259-1, HIGASHISHIIJI, NUMAZU-SHI, SHIZUOKA 410-0302
13 AWAMURA JUNICHI GRAND COURT 203, 737-1, SHIMONAGAKUBO, NAGAIZUMI-CHO, SUNTO-GUN, SHIZUOKA 410-0934
14 TOMITA ,MASAMI PASCO GRAND MANSION SHINNUMAZU 302, 19-1, SHINJUKU-CHO, NUMAZU-SHI, SHIZUOKA 410-0048
15 HONDA TAKAHIRO TAKASHIMAHONCHO M'S 304, 2-21, TAKASHIMAHONCHO, NUMAZU-SHI, SHIZUOKA 410-0055
16 YAGI SHINICHIRO 726-2, SHIMOKANUKIYANAGIHARA, NUMAZU-SHI, SHIZUOKA 410-0822
17 SUZUKI TOMOMI TRES DIAS A-101, 2196, OOKA, NUMAZU-SHI, SHIZUOKA 410-0022
18 YAMADA HIROSHI SEAGULL 2-103, 841-1, OOKA, NUMAZU-SHI, SHIZUOKA 410-0022
19 NANYA TOSHIKI 40-1, FUJIMIDAI. MISHIMA-SHI, SHIZUOKA 410-0021
20 HIGUCHI HIROTO SEMUI HEIGHTS 101,387-1, OZUWA, NUMAZU-SHI, SHIZUOKA 410-0873
21 SASAKI FUMIHIRO 2657-73, IMAIZUMI, FUJI-SHI, SHIZUOKA 417-0001
22 SHIMOTA NAOHITO BELL SHINE TAKEHARA A-103, 344-6, TAKEHARA, NAGAIZUMI-CHO, SUNTO-GUN, SHIZUOKA 411-0944
23 MOCHIZUKI SATOSHI ANGEL HEIM OKAISSHIKI 2-601, 27-1, OKAISSIKI, NUMAZU-SHI, SHIZUOKA 410-0012
PCT International Classification Number G03G9/087; G03G15/20
PCT International Application Number PCT/JP2004/013559
PCT International Filing date 2004-09-16
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2004004424 2004-01-09 Japan
2 2003325532 2003-09-18 Japan