Title of Invention

INK FOR INKJET RECORDING, INK SET FOR INKJET RECORDING, INK MEDIA SET FOR INKJET RECORDING, INK CARTRIDGE, INKJET RECORDING METHOD, AND INKJET RECORDING APPARATUS

Abstract The invention discloses an ink for inkjet recording, comprising: water; a water-soluble organic solvent, such as herein described; a polyurethane resin emulsion; a fluorochemical surfactant or derivative thereof, such as herein described; and a coloring agent containing a pigment, wherein the ink for inkjet recording has a surface tension of 20 mN/m to 35 mN/m at 25°C, and a viscosity of 5 mPa•s or more at 25°C, a total amount of the polyurethane resin emulsion and the coloring agent in the ink for inkjet recording is 5% by mass to 40% by mass, and a mass ratio A/B of the polyurethane resin emulsion A to the coloring agent B is 0.5 to 4. The invention also discloses an ink set for inkjet recording, an ink media set for inkjet recording, an ink cartridge, an inkjet recording method and an inkjet recording apparatus as described in the specification.
Full Text

DESCRIPTION
Technical Field
The present invention is directed to an ink for inkjet recording,
ink set for inkjet recording, ink media set for inkjet recording, ink
cartridge, inkjet recording method, and inkjet recording apparatus,
which realize recordings of high quality images by an inkjet system, and
those quality of images close to that of commercial printing such as off-
set printing.
Background Art
Inkjet recording has been known as an excellent recording
method in which substantially any recording media (hereinafter, the
recording media may also be referred to as " a recording medium", "inkjet
paper", "recording media for inkjet recording" or "media") can be applied,
and it has been extensively studied and improved in terms of a recording
apparatus, recording method, and recording medium thereof. In the art,
the widely used ink for inkjet recording is the one which contains water
as a main component, and an aqueous dye. The reason for the large
demand in such the ink is that this ink uses easily obtainable dyes
having high absorption coefficient and high color purity, handling of this
ink is very easy when the ink is made in multiple colors for purpose of

widening the range of color tones thereof, and the ink can be made so as
to have good long-term storage stability and high heat resistance
stability, and especially to prevent deterioration or blockage of a thermal
head as a result of the ink being suffered from a heat from a heater for a
long period.
Conventional inkjet papers, especially gloss media for inkjet
printing, are classified into mainly two types, a swollen type and a
porous type. Recently, the porous type media have been widely used
since they excel in drying speed of the ink. The structure of the typical
porous media is such that onto a support, there is provided an ink
absorbing layer having pores so as to take the ink therein, and porous
glossy layer is optionally provided on the ink absorbing layer. For
example, Patent Literatures 1 and 2 disclose a porous medium which is
obtained by applying, onto a support, a coating liquid wherein silica and
aluminum hydrate are dispersed therein to form one or more layers, and
optionally applying a coating liquid containing colloidal silica so as to
form a glossy layer containing a large amount of the colloidal silica.
This medium is so designed as to match a dye ink which is currently
mainly used in inkjet recording, and is widely used as a medium for
inkjet printing, especially as a glossy paper. This paper realizes an
output image with high gloss and of extremely precise details. However,
it also has drawbacks such that raw materials thereof are very expensive,
and the production process for this type of paper is very complicated.
Therefore, a production cost for the paper is extremely high compared to
a glossy coated paper for general commercial printing. For this reason,

use of this paper is limited to cases where high quality output images are
required, such as outputting of photography or the like, and it is hardly
used in the field of the commercial printings which need large numbers
of outputting at low cost, such as flyers, catalogs, brochures, and the like.
Moreover, there is a demand for improving the ink absorption capability
since the numbers of colors of the ink for use are getting larger for
obtaining higher quality of images. In order to improve the ink
absorption capability, a thickness of an ink accepting layer, i.e. a coated
layer, needs to be increased. However, if the thickness is increased, a
larger quantity of expensive materials is required. Therefore, there is a
problem such that a cost required for producing each medium is
increased.
A pigment used in the ink absorbing layer, i.e. the ink accepting
layer, needs to have a low refractive index and opacity which allow to
maintain high transparency of the ink absorbing layer, and needs to have
large oil absorption or specific surface area. Therefore, it is necessary to
add a large amount of expensive pigments having a low refractive index
and high oil absorption, such as silica and aluminum hydrate, not
inexpensive white pigments such as calcium carbonate, kaolin, and the
like. When the ink absorbing layer contains pigments having low
transparency and high opacity, a coloring material contained in the ink
absorbed in the ink absorbing layer is concealed by such pigments, and
thus a high coloring density cannot be obtained. In the case where
inkjet recording is carried out by using a paper containing such pigments
of high opacity together with an ink containing a dye, the color density of

the resulted image is corresponding to only the coloring material present
in the surface area of the paper even though the amount of the ink to be
ejected is increased. Therefore, the resulted image has low color density
on the whole, and has low contrast. In the case where the pigment
having low oil absorption is used in a paper, the absorption of the ink
cannot be carried out sufficiently, and thus bleeding tends to occur.
In order to resolve the above-mentioned problems, Patent
Literature 3 proposes to use fine organic particles having a low refractive
index so as to realize both the desirable refractive index and whiteness.
However, the organic fine particles still lead to high production cost, and
thus it is yet difficult to attain a recording medium designed for an ink
containing a dye, at low cost.
Moreover, as a design for improving a long-term stability of a
printed image, a main stream idea is to penetrate a dye into an ink-
accepting layer as deep as possible so as to block influences from air or
ultraviolet ray as much as possible, and to protect the dye by using an
antioxidant, or a stabilizer which are originally present within the ink
accepting layer, since the dye molecule has low resistance to ultraviolet
rays and ozone. Therefore, a deep penetration is realized by using a
large amount of an ink having a relatively low content of the coloring
agent, so as to maintain image reliability. To this end, an amount of the
ink necessary for outputting an image is automatically increased.
Therefore, downsizing of a cartridge is difficult to realize, as well as
increasing a cost for recording.

Under these circumstances, in inkjet recording, it is still difficult
to provide a recording medium for inkjet recording and a recording
method which output high quality images at low cost.
In recent years, attentions have been drawn to a pigment ink for
inkjet recording. The pigment is insoluble to water, and thus the
pigment is generally dispersed in a solvent in the form of fine particles.
In view of safety, a pigment ink wherein the pigment is dispersed in
water is mainly used in the art. However, such pigment ink has
drawbacks as mentioned hereinafter. The aqueous pigment ink tends to
cause more aggregations or precipitation of the pigment particles,
compared to a dye ink. In order to improve long-term storage stability
to the same degree to that of the dye ink, various conditions for
dispersion or additives are required. The dispersion stabilizer however
becomes a factor for causing a blockage of a thermal head as a result of
the ink being suffered from a heat from a heater for a long period.
Therefore, such ink is not suitably used with a thermal head. Moreover,
the pigment ink is inferiors to a dye ink in a color specification range of
coloring agents. Although the pigment ink has these drawbacks, it has
been popular in view of storage stability after recording, water-resistance,
and image reliability such that high color density of black can be
attained. It is considered that an inkjet printer using the pigment ink
enables to realize the prints having the improved textures to the level of
those of commercial printing, as the coloring agents used therein are
close to those of general commercial printing. However, when printing
is actually performed on a coated paper for commercial printing by using

the conventional pigment ink, drying speed of the ink is not sufficiently
high. This poor drying property causes problems such that an image is
spread or blurred, the pigment is not fixed at all after drying, abrasion
occurs, and the like. Therefore, in reality, the pigment ink can be used
only for printing of media having high absorption of an ink, such as a
normal paper, a recording paper for inkjet recording, and the like. This
is because the designing concept of an inkjet image using the pigment
ink has not changed from that of an inkjet image using the dye ink, the
pigment coloring agent is considered only as a dye having a high light
fastness, and the characteristics of the pigment ink are disregarded.
Moreover, an ink for inkjet recording containing amino acid and
the like has been known in the art. However, no attempt has been made
to improve a quality of an image printed on a coated paper for
commercial printing, by using this ink. For example, Patent Literature
4 discloses an essentially combination of amino acid (including dipeptide)
and an amphoteric surfactant as components of an ink and a use of this
ink so as to reduce a permeability of the ink into a normal paper and the
like for the purpose of improving water-resistance, bleeding, feathering,
or the like on a normal paper as a challenge for the dye ink, and also
proposes to use amino acid or the like in the ink for the purpose of
obtaining excellent optical density.
Patent Literature 5 proposes an ink containing protein or
dipeptide, further containing a combination of amino acid and a certain
surfactant, for the purpose of improving reliability for preventing
clogging of a thermal head. Regarding the reliability for preventing

clogging, this literature discloses that the protein or peptide contained in
the ink is decomposed due to the structure thereof at the time of using
with a thermal head, the decomposed products are deposited on a head
heater area resulting in a blockage of a thermal head, and therefore the
reliability is significantly lowered. It is further discloses that the above-
mentioned lowered reliability for preventing clogging is prevented, and
the reliability for preventing clogging is maintained by further adding
amino acid and a certain surfactant in combination in the ink.
Patent Literature 6 proposes to add saccharide, reduced
saccharide, oxidized saccharide, and the like to an ink for the purpose of
improving reliability for preventing clogging, and also discloses that the
clogging is prevented by using such the ink as the water evaporation of
the ink is inhibited around a nozzle. However, the ink disclosed in this
literature is not a pigment ink wherein a moisture content of the ink is
reduced and dipeptide is added, so as to realize both of reliability for
preventing clogging, and media conveyance and image reliability for
preventing beading and cockling, at the time using with commercial
media having low absorption of the ink. Here, the term "image
reliability" means light fastness, water-resistance and fixing ability of
characters or image printed on the media.
Moreover, urea or the like is also listed as a solid moisture
retainer in this literature, but comparing to dipeptide, urea has problems
such that it tends to slightly increase viscosity of the ink with the same
addition amount to that of the peptide, and may increase viscosity of the

ink or cause aggregation of a coloring agent due to decomposition thereof
ad the time of storage at high temperature.
[Patent literature 1] Japanese Patent Application Laid-Open (JP-A) No.
2005-212327
[Patent literature 2] JPA No. 199978225
[Patent literature 3] JPA No. 200325717
[Patent literature 4] JPA No. 200515795
[Patent literature 5] JPA No. 2006117634
[Patent literature 6] JPA No. 2006122900
Disclosure of Invention
First of all, the present invention aims at providing an ink for
inkjet recording, an ink set for inkjet recording, an ink media set for
inkjet recording, an ink cartridge, an inkjet recording method, and an
inkjet recording apparatus, which produce prints having a high printing
quality, excellent density, gloss, and image reliability, like those of
commercial printings, but at low cost, and also realize excellent
reliability such as high ejecting stability, and high storage stability by
selectively utilizing a certain recording medium for inkjet recording, and
a certain pigment ink for inkjet recording in combination.
Secondly, the present invention aims at providing an ink for
inkjet recording, an ink set for inkjet recording, an ink media set for
inkjet recording, an ink cartridge, an inkjet recording method, and an
inkjet recording apparatus, which produce prints having a high
capability of media conveyance in term of preventing beading of adjacent
dots and cockling of a recording medium, excellent density, gloss, and

image reliability, like those of commercial printings, but at low cost, and
also realize excellent reliability such as stability in terms of preventing
nozzle clogging, and high storage stability by selectively utilizing a
certain recording medium for inkjet recording, and a certain pigment ink
for inkjet recording in combination.
The means for solving the above problems are as follows.
An ink for inkjet recording, comprising:
water;
a water-soluble organic solvent."
a water-dispersible resin?"
a fluorochemical surfactant or derivative thereof and
a coloring agent containing a pigment,
wherein the ink for inkjet recording has a surface tension of 20
mN/m to 35 mN/m at 25°C, and a viscosity of 5 mPa•s or more at 25°C,
a total amount of the water-dispersible resin and the coloring agent in
the ink for inkjet recording is 5% by mass to 40% by mass, and a mass
ratio A/B of the water-dispersible resin A to the coloring agent B is 0.5 to
4,
wherein the Ink for inkjet recording is applied for a recording
medium for inkjet recording which comprises a support containing a
cellulose pulp, and one or more barrier layer disposed on at least one face
of the support, and
wherein the barrier layer comprises 30% by mass or more of an
inorganic pigment having a refractive index of 1.5 or more, excluding

aluminum hydrate, and 10% by mass or more of an inorganic pigment
having a refractive index of less than 1.5.
The ink for inkjet recording according to , wherein the
water-dispersible resin is at least one selected from the group consisting
of an anionic self-emulsified polyurethane ether resin emulsion and an
acryl-silicone resin emulsion.
The ink for inkjet recording according to or , wherein
the surfactant is a compound expressed by the following structural
formula l:

Structural formula 1
in the structural formula 1, each of R1 and R3 denotes either a
hydrogen atom or a group containing a fluorine atom, each of R2 and R4
denotes a group containing a fluorine atom, and each of m, n, p, q and r
denotes an integer.
An ink for inkjet recording, comprising:
water;
a water-soluble organic solvent;
a water-dispersible resin;

a coloring agent; and
a solid moisture retainer containing a dipeptide,
wherein the ink for inkjet recording has a surface tension of 20
mN/m to 35 mN/m at 25°C, and a viscosity of 5 mPa•s or more at 25°C,
wherein the ink for inkjet recording is applied for a recording
medium for inkjet recording which comprises a support containing a
cellulose pulp, and one or more barrier layer disposed on at least one face
of the support, and
wherein the barrier layer comprises 30% by mass or more of an
inorganic pigment having a refractive index of 1.5 or more, excluding
aluminum hydrate, and 10% by mass or more of an inorganic pigment
having an refractive index of less than 1.5.
The ink for inkjet recording according to , wherein the
dipeptide is at least one selected from the group consisting of alanyl
glutamine, glycyl glutamine, bisalanyl cysteine, and bisglycyl cysteine.
The ink for inkjet recording according to any one of to
, wherein the water-soluble organic solvent is at least one selected
from the group consisting of glycerin, trimethylol propane, ethylene
glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene
glycol, tripropylene glycol, 2-methyll,3propanediol, 1,3-butanediol, 2,3"
butanediol, 1,4-butanediol, 2-methyl- 1,3-butanediol, 3-methyM,3-
butanediol, .1,5-pentanediol, l,6hexanediol, 2-methyl-2,4-hexanediol, 2-
pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone,
tetramethyl urea, and urea.
An ink set for inkjet recording, comprising:

a black ink," and
a color ink,
wherein each of the black ink and the color ink is the ink for
inkjet recording according to any one of to .
An ink media set for inkjet recording, comprising:
the ink for inkjet recording according to any one of to ;
and
a recording medium for inkjet recording,
wherein the ink contains the coloring agent containing a pigment,
contains the water-dispersible resin and the coloring agent at an amount
of 5% by mass to 40% by mass in total, and has a mass ratio A/B of the
water-dispersible resin A to the coloring agent B is 0.5 to 4,
wherein the recording medium for inkjet recording contains a
support containing a cellulose pulp, and one or more barrier layer
disposed on at least one face of the support, and
wherein the barrier layer comprises 30% by mass or more of an
inorganic pigment having a refractive index of 1.5 or more, excluding
aluminum hydrate, and 10% by mass or more of an inorganic pigment
having an refractiveindex of less than 1.5.
The ink media set for inkjet recording according to ,
wherein the barrier layer has a thickness of 10 µm or less.
The ink media set for inkjet recording according to any one
of or , wherein the barrier layer has pores having a diameter of 1
µm or less, and a ratio of an area of the pores occupying in the face of the
recording medium for inkjet recording is 40% or less.

An ink cartridge, comprising:
a container; and
the ink for inkjet recording according to any one of to ,
contained in the container.
An inkjet recording method, comprising:
applying a stimulus to an ink of the ink media set according to
any one of to and ejecting the ink so as to record an image on a
recording medium of the ink media set according to any one of to
.
The inkjet recording method according to , wherein the
stimulus is at least one selected from the group consisting of heat,
pressure, vibration, and light.
The inkjet recording method according to or ,
wherein the ink is ejected so that the image is recorded at an ink
deposited amount of 15 g/m2 or less.
An inkjet recording apparatus, comprising:
the ink media set for inkjet recording according to any one of
to ; and
an ink ejecting unit configured to apply a stimulus to the ink, and
to eject the ink so as to record an image on the recording medium.
The inkjet recording apparatus according to , wherein
the stimulus is at least one selected from the group consisting of heat,
pressure, vibration, and light.
The inkjet recording apparatus according to or ,
wherein the ink ejecting unit ejects the ink on the recording medium so

that an ink deposited amount on the recording medium to be 15 g/m2 or
less.
The inkjet recording apparatus according to any one of
to , further comprising a member configured to turn over a side of
the recording medium so as to enable a double-side printing.
According to the present invention, firstly, there are provided an
ink for inkjet recording, an ink set for inkjet recording, an ink media set
for inkjet recording, an ink cartridge, an inkjet recording method, and an
inkjet recording apparatus, which produce prints having a high printing
quality, excellent density, gloss, and image reliability, similar to those of
commercial printings, but at low cost, and also realize excellent
reliability such as high ejecting stability, and high storage stability by
selectively utilizing a certain recording medium for inkjet recording, and
a certain pigment ink for inkjet recording in combination.
According to the present invention, secondly, there are provided
an ink for inkjet recording, an ink set for inkjet recording, an ink media
set for inkjet recording, an ink cartridge, an inkjet recording method, and
an inkjet recording apparatus, which produce prints having a high
capability of media conveyance in term of preventing beading of adjacent
dots and cockling of a recording medium, excellent density, gloss, and
image reliability, similar to those of commercial printings, but at low cost,
and also realize excellent reliability such as stability in terms of
preventing nozzle clogging, and high storage stability by selectively
utilizing a certain recording medium for inkjet recording, and a certain
pigment ink for inkjet recording in combination.


Brief Description of Accompanying Drawings
FIG. 1 schematically shows an example of an ink cartridge of the
present invention.
FIG. 2 schematically shows an exterior of the ink cartridge of FIG.
1 including a casing thereof.
FIG. 3 shows a perspective view of an inkjet recording apparatus,
wherein a section where an ink cartridge is loaded is shown with a cover
thereof open.
FIG. 4 schematically shows an example of an entire construction
of the inkjet recording apparatus.
FIG. 5 schematically shows an enlarged view of an example of an
inkjet head suitable for use in the inkjet recording apparatus of the
present invention.
FIG. 6 shows an enlarged view of an example of an inkjet head
suitable for use in the inkjet recording apparatus of the present
invention.
FIG. 7 shows an enlarged cross-sectional view of an example of an
inkjet head suitable for use in the inkjet recording apparatus of the
present invention.
Best Mode for Carrying Out the Invention
(Ink for inkjet recording, Ink media set for inkjet recording, and Ink set
for inkjet recording)
The ink for inkjet recording of the present invention is designed
for recording on a recording medium for inkjet recording which contains

a support containing a cellulose pulp, one or more barrier layer disposed
on at least one face of the support, by a inkjet recording system.
A first embodiment of the ink according to the present invention
contains water, a water-soluble organic solvent, a water-dispersible resin,
a fluorochemical surfactant, and a coloring agent, and optionally
contains other substances, if necessary.
A second embodiment of the ink according to the present
invention contains water, a water-soluble organic solvent, a coloring
agent, and a solid water retainer, and optionally contains other
substances, if necessary.
The ink media set for inkjet recording of the present invention
contains either the first or second embodiment of the ink, and a
recording medium for inkjet recording, which contains a support
containing a cellulose pulp, one or more barrier layer disposed on at least
one face of the support, wherein the barrier layer contains 30% by mass
or more of an inorganic pigment having a refractive index of 1.5 or more,
but other than aluminum hydrate, and 10% by mass or less of an
inorganic pigment having a refractive index of less than 1.5.
The ink set for inkjet recording of the present invention contains
a black ink and a color ink, wherein the black ink and the color ink are
each selected from the first and second embodiments of the ink.
Examples of the color ink are a yellow ink, a magenta ink, a cyan
ink, and the like. If a recording is performed with two or more inks
selected from the black ink, the yellow ink, the magenta ink, and the
cyan ink in combination, a multiple color image can be formed. If a

recording is performed with inks of all colors in. combination, a full color
image can be formed.
[Recording medium for inkjet recording]
As an example of the conventional recording medium for inkjet
recording, a coated paper for inkjet recording is widely used, and is
generally believed to yield a high quality image. The coated paper is
designed to absorb or penetrate an ink in an ink accepting layer disposed
on a surface of a support, or adjacent to the surface of the support, to
thereby form an image. This design is closely related to the fact that a
focus of the developments for an ink has mainly been directed to a dye
ink in the technology of inkjet recording.
A dye in a liquid is generally penetrated into a material having
an affinity to the dye, and is bound to such material by covalent bonding,
ionic bonding, Van del Waals face, or the like, to thereby tint the material.
On the other hand, a pigment has no or only little self-binding force, and
thus the pigment requires an adhesive or binder to bind with another
material. In the case where a dye ink in used for inkjet recording, the
recording is performed by "dying" the materials in the accepting layer.
Since the person in the art needed to consider this dying process, there
were the technical problems to be solved, such as how to uniformly dye
the accepting layer by using the ink for inkjet printing, and how to
improve so as to dye various materials used in the accepting layer with
the ink for inkjet recording. To solve such problems and obtain high
density and quality images, the technique for absorbing more ink in the
accepting layer, the technique for more strongly binding the ink to the

materials in the accepting layer, and the technique for attaining both
absorbance of ink and coloring quality in a good balance have been
developed.
As mentioned earlier, the main stream for the current paper for
inkjet recording is the one having an absorbing layer which has high
porosity and transparency. To obtain such the layer, it is necessary to
use a material which has a low refractive index and a large specific area,
and the current situation is such that an expensive material, e.g. silica or
alumina hydrate, needs to be used, and highly complicated production
method is required. Therefore, the printing cost naturally becomes high,
and thus it is difficult to use this technique for mass printing or the like
due to its cost.
In view of the above-mentioned problems in the art, the present
inventors had diligently studied for realizing an inkjet recording method
at lower cost, and they came to invent an inexpensive image forming
method by using a certain pigment ink having a high penetration ability,
and a recording medium which had a low ink absorbing capacity, which
was contrary to the trends in the art, in combination, based on a novel
concept of design.
Specifically, printing is performed on a recording medium that is
controlled to absorb a pigment as a coloring material contained in the ink
as little as possible, by using a little amount of the pigment ink having
extremely high penetration ability. In this manner, a solvent contained
in the ink is selectively absorbed in the support, the coloring material, i.e.
a pigment, in the ink is efficiently remained on the surface of the

recording medium, and thus sufficient coloring density and drying speed
can be both attained with a little amount of the ink.
The recording medium of the present invention that is controlled
with the ink absorbing amount can be attained for example by applying
or coating an absorption inhibiting layer for a certain pigment coloring
agent, i.e. a barrier layer on a support containing a cellulose pulp as a
main component, i.e. a paper support. This barrier layer is configured
to resemble its appearance to that of a printing paper, and therefore
prints having textures close to conventional commercial printings can
also be attained. The desirable penetration, i.e. barrier property, of the
barrier layer can be attained by controlling a size and diameter of pores
in the barrier layer, a thickness of the barrier layer, and the like.
In order to encourage the separation of the pigment coloring
agent from solvent of the ink, the barrier layer preferably has a certain
thickness or less. This thickness is preferably 10 µm or less, and is

more preferably 5 µm or less. If the thickness of the barrier layer is
larger than this range, the time required for penetrating the solvent of
the ink is prolonged, and thus the image quality may be decreased due to
the occurrence of beading, breading, or the like, and offset or the like
tends to be occurred as the drying capability is decreased. Moreover,
since it is necessary to make the barrier layer thin, the barrier layer is
designed to contain a large amount of an inorganic pigment having a
high refraction index and high opacity, contrary to a barrier layer used in
a conventional medium for inkjet recording to thereby inhibit blotting of
the coloring agent to the bottom side of the medium, namely to inhibit

the phenomena that the printed color from the coloring agent is seen
from the bottom side of the medium. Therefore, it is required that the
barrier layer contains 30% by mass or more of an inorganic pigment
having a refractive index of 1.5 or more, preferably 40% by mass or more
of the same, and even more preferably from 50% by mass or more up to
less than 90% by mass of the same. The barrier layer may optionally
contain silica which has low opacity and low refractive index, used for
the conventional recording medium for inkjet recording, but the content
thereof needs to be 10% by mass or less as the above-mentioned blotting
of the ink is increased and a cost is increased when a large amount of a
highly transparent pigment is added. To sum up, by using a white
pigment having a high refractive index in the barrier layer, a thinned
barrier layer can be attained while reducing the blotting of the ink and
the cost.
Moreover, some of aluminum hydrate is generally listed as a
pigment having a high refractive index. If such pigment as aluminum
hydrate which has a high oil absorbing capacity is added at a large
amount in the barrier layer, a solvent of the ink is not easily transferred
to the support from the barrier layer. The aluminum hydrate absorbing
a large amount of the solvent causes smear in an image due to
discoloration or migration of the pigment during a long-term storage, and
thus it is not acceptable in the present invention.
The functions required for the barrier layer are to separate the
pigment from the solvent in the ink, and to allow only the solvent to
penetrate into the support. To this end, it is preferable that the barrier

layer has fine cavities, i.e. pores, therein. In the case where no pore is
present in the barrier layer, the penetration of the solvent in the ink is
delayed, or the ink is hard to dry. However, if the diameter of the pores
is excessively large or excessively large numbers of the pores are present
in the barrier layer, the function to separate the pigment from the
solvent of the ink is lowered, and thus an image density may be
decreased, or the pigment present on the surface of the recording
medium after printing starts migrating into the recording medium with
age, resulting in a change in the color. Therefore, a diameter of the
pores is preferably 1 µm or less, and an area of pores occupying in the
surface of the recording medium is preferably 40% or less.
The measurements for the diameter of the pores and the area of
the pores occupying in the surface of the recording medium can be
carried out by observing the surface of the recording medium on a
photography taken by means of Scanning Electron Microscopy (SEM).
Based on the surface picture, an image of the area of the pores is
translated into 2 digits, and a diameter and area ratio thereof can be
obtained. In the present invention, a field emission scanning electron
microscope HSM-7400F manufactured by JEOL Ltd. is used as a SEM
instrument, and Pop Imaging Ver. 3.51 manufactured by Digital Being
Kids Limited is used for image processing.
Examples of the inorganic pigment for use in the present
invention are: magnesium carbonate, talc, kaolin, illite, clay, calcium
carbonate, calcium sulfite, titanium white, magnesium carbonate,
titanium dioxide, and the like. By selecting and using the pigment

having higher refraction index from these pigments, a thickness of the
barrier layer can be thinned. In view of the cost, however, calcium
carbonate and kaolin are preferable therefrom. These pigments can be
used in combination provided that they do not adversely affect the effects
of the present invention. Moreover, these pigments may also be used in
combination with other pigments than the ones listed above. Kaolin is
preferably used, because kaolin gives excellent gloss, and realizes a
recording medium having a texture close to that of a medium for offset
printing. Kaolin includes delaminated kaolin, fused kaolin, engineered
kaolin which is surface processed, and the like. In view of glossiness,
kaolin preferably has 50% by mass or more of kaolin particles which have
a particle size distribution of such that 80% by mass or more of particles
having the diameter of 2 µm or less, with respect to the total amount of
kaolin particles. The content of kaolin is preferably 50 parts by mass or
more. If the content is less than 50 parts by mass, an effect in
glossiness cannot sufficiently be exhibited. There is no upper limit for
the added amount of kaolin, but it is preferably less than 90 parts by
mass in view of coating applicability under consideration of fluidity of
kaolin, especially that increased viscosity at high shearing force.
Moreover, such pigment having high refractive index can be used
together with silica that has low refractive index or an organic pigment.
Examples of the organic pigment include aqueous dispersion of particles
such as styrene-acryl copolymer particles, styrene-butadiene copolymer
particles, polystyrene particles, polyethylene particles, or the like. Two
or more of these organic pigments may used in combination. Since the

organic pigment gives excellent gloss and its relative mass is smaller
compared to an inorganic pigment, a coating layer of desirable bulkiness,
high gloss, and excellent coating ability can be attained. However, if the
content of the organic pigment is less than 2 parts by mass, the above-
mentioned effects cannot be attained. On the other hand, if the content
is more than 5 parts by mass, ink setoff may occur and also it is not
effective in terms of cost. The organic pigment has configurations such
as solid, hollow, doughnut shaped, and the like. Considering the
balance between gloss exhibition, surface coating ability, and fluidity of a
coating liquid, it is preferable that the organic pigment has an average
particle diameter of 0.2 µm to 3.0 µm, and it is more preferably that
hollow organic pigment having void ratio of 40% or more is used.
A binder of the barrier layer for use in the present invention is
selected without any particular restriction, provided that it is a water-
soluble resin, emulsion, and the like, which do not cause blocking.
Examples of the water-soluble resin include polyvinyl alcohol, a starch
such as an oxidized starch, an esterified starch, an enzyme modified
starch, a cationatid starch, or the like, a cellulose derivative such as
casein, soy protein, Carboxymethyl cellulose, hydroxyethyl cellulose, or
the like, styrene-acryl copolymer, isobutylene-maleic anhydride, acrylic
emulsion, polyvinyl acetate emulsion, vinylidene chloride emulsion,
polyester emulsion, styrene-butadiene copolymer latex, acrylnitrile-
butadiene copolymer latex, and the like. Among these, the starch and
the styrene-butadiene copolymer latex are preferable for use in view of
the cost.

The styrene-butadiene copolymer latex is copolymer latex
generally used for coating a paper, which contains styrene and butadiene
as monomers, optionally contains other monomers to copolymerize, and
optionally is a copolymer modified by a chemical reaction. Examples of
the other monomers include acrylic acid, methacrylic acid alkyl ester of
acrylic acid or methacylic acid, acrylnitrile, maleic acid, fumaric acid,
vinyl monomer such as vinyl acetate, and the like. In addition, the
styrene-butadiene copolymer latex optionally contains a crosslinking
agent such as methylol melamine, methylol urea, methylol
hydorxypropylene urea, isocyanate, or the like, or contains self-
crosslinkable copolymer containing a unit such as N-methylolacrylamide.
One of them may be used, or two or more of them may be used in
combination in the styrene-butadiene copolymer latex.
A solids content of the water-soluble binder is preferably 50% by
mass to 70% by mass, more preferably 55% by mass to 60% by mass with
respect to the total solids of the barrier layer.
In the case where the solids content is small, the binding ability
becomes insufficient, to thereby lower the strength of the ink accepting
layer and the binding strength between the components within the layer
to cause flaking.
Other components can be added to the barrier layer, if necessary,
provided that such components do not adversely affect the objects and
effects of the present invention. Examples of such components include
various agents usually mixed with a pigment for coating, such as a
surfactant, a dispersing agent, a thickener, a moisture retainer, an

antifoaming agent, a waterproof agent, or the like, and additives such as
a pH controlling agent, a preservative, an antioxidizing agent, a cationic
organic compound, or the like.
The surfactant for use in the barrier layer can be selected from an
anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a
nonionic surfactant depending on the purpose without any restriction.
Among the listed surfactants above, the nonionic surfactant is
particularly preferable.
Examples of the nonionic surfactant include a high alcohol
ethylene oxide adduct, an alkylphenol ethylene oxide adduct, a fatty acid
ethylene oxide adduct, a polyhydric alcohol fatty acid ester ethylene
oxide adduct, a higher aliphatic amine ethylene oxide adduct, a fatty acid
amide ethylene oxide adduct, an ethylene oxide adduct of oils and fats, a
polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerol,
fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan,
fatty acid ester of sucrose, alkyl ether of polyhydric alcohol, fatty acid
amide of alkanol amide, and the like. As the nonionic surfactant, one of
them may be used, or two or more of them may be used in combination.
The polyhydric alcohol is appropriately selected without any
restriction. Suitable examples thereof are glycerol, trimethylol propane,
penterythrite, sorbitol, sucrose, and the like. Suitable examples of the
ethylene oxide adduct include ethylene having a part of which is
substituted with alkylene oxide such as propylene oxide or butylene
oxide, provided that a water-solubility thereof is maintained. The
substitution rate is preferably 50% or less. Hydrophilic-lipophilic

balance (HLB) of the nonionic surfactant is preferably 4 to 15, more
preferably 7 to 13.
It is not necessary to add the cationic organic compound, but the
cationic organic compound can be appropriately added depending on the
purpose without any restriction.
Examples of the cationic organic compound include a
condensation product of dimethyl amine and epichlorohydrin, a
condensation product of dimethyl amine, ammonium, and
epichlorohydrin, poly(jethacrylic acid triethylaminoethyl-
methylsulphate), a copolymer of polyacrylic amine and diacryl amine, a
copolymer of polyvinyl amine, dicyane diamide, a condensation product of
dicyane diamide, ammonium chloride, urea, and formaldehyde, a
condensation product of polyalkylene polyamine and ammonium dicyane
diamide, dimethyldiarylammonium chloride, polydiarylmethylamine
hydrochloride, poly(diaryldimethylammoniumchloride),
poly(diaryldimethylammoniumchloride-sulfur dioxide),
poly (diaryldimethylammoniumchloride - diarylamine hydrochloride
derivative), a copolymer of acrylamine and
diaryldimethylammoniumchloride, a copolymer of acrylate, acrylamide,
and diarylamine hydrochloride, polyethyleneimine, ethylene imine
derivative such as acrylamine polymer or the like, a modified product of
polyethyleneimine alkylene oxide, and the like. One of them may be
used, or two or more of them may be used in combination as the cationic
organic compound.
Support-

The support for use in he present invention is one produced hy
mixing chemical pulps, mechanical pulps, recycled pulps and the like at a
predetermined ratio, optionally adding therein an internally adding
sizing agent, a retention aid, a paper strength additive, and the like, and
making paper from the mixture by means of a fourdrinier former, a gap-
type twin-wire formed, or a hybride former that is a fordrinier having its
latter part modified with twin-wire.
The pulps used for the support contains- virgin chemical pulp
(CP) which is obtained by chemically treating wood and its fibrous
material, such as a bleached hardwood kraft pulp, a bleached softwood
kraft pulp, an unbleached hard wood kraft pulp, an unbleached soft wood
kraft pulp, a bleached hard wood sulfite pulp, a bleached softwood sulfite
pulp, an unbleached hardwood sulfite pulp, an unbleached softwood
sulfite pulp, and the like; and virgin mechanical pulp (MP) which is
obtained by mechanically treating wood and its fibrous material, such as
a ground pulp, a chemiground pulp, a chemi-mechanical pulp, a semi-
chemical pulp, and the like.
The recycle pulp can also be used in the support, and raw
materials of the recycle pulp are, for example, papers defined as terms of
"high white", "line white", "cream white", "card", "special white", "mild
white", "imitation", "color high", "Kent", "white art", "special high cut",
"separate high cut", "news paper", "magazine", and the like in Standard
Chart of Recycled Paper, produced by Paper Recycling Promotion Center
that is Japanese non-profit foundation (the above-mentioned definitions
can be found in the chart). Specific examples include: printing papers

such as a non-coated paper for personal computers, that is paper for
information technology or the like, a thermosensitive paper, a pressure
sensitive paper, and the like," a recycled OA paper such as paper for PPC;
an art paper, a coated paper, a slightly coated paper, a matt paper, and
the like; recycle papers or cardboards of high quality papers, of high
quality color papers, of a paper from note books, of a paper from letter
pads, of lapping papers, of fancy papers, of middle quality papers, of
news paper, of bank papers, of lapping papers used in supermarkets, of
imitation papers, of pure-white rolling papers, of non-coated papers such
as milk cartons, and the like, and those examples listed above are papers
containing chemical pulps, papers containing high yield pulps, and the
like. One of these may be used or two or more of them may be used in
combination as the recycled pulp.
The recycled pulp is generally produced by the combination of the
following four steps.
(1) Breaking out of a recycled paper is carrier out by treating the paper
with mechanical force or chemical by means of a pulper so as to break
down to fibers, and detaching the printing ink from the fibers.
(2) Removal of dusts is carried out by removing foreign substances and
dusts obtained in the recycled paper by a screen or a cleaner.
(3) Removal of an ink is carrier out by removing the detached ink from
the fibers using a surfactant in accordance with a flotation method or
washing method, to thereby remove from the system.
(4) Bleaching is carrier out by using an oxidation reaction or a reduction
reaction to thereby increase whiteness of the fibers.

In the case where the recycled pulp is added to the pulp used for
the support, the mixing amount of the recycled pulp is preferably 40% or
less based on the total amount of the pulp for the purpose of preventing
curling of the support after recording.
As an additive used in the support, calcium carbonate is effective,
but calcium carbonate can be used in combination with inorganic
additives such as kaolin, calcined clay, pyrophylite, sericite, silicic acids
such as talc, and the like, satin white, barium sulfate, calcium sulfate,
zinc sulfate, and organic pigments such as a plastic pigment, a urea resin,
and the like.
The internally adding sizing agent for use in the support is
suitably selected from conventional internally adding sizing agents used
for inkjet recording mediums, without any particular restrictions.
Suitable internally adding sizing agents are, for example, a rosin
emulsion sizing agent, and the like. The internally adding sizing agent
used at the time when a sheet of the support is made is, for example,
neutral rosin sizing agent used for making neutral paper, alkenyl
succinic anhydride (ASA), alkyl ketene dimer (AKD), petroleum resin
sizing agent, or the Eke. Among these, the neutral rosin sizing agent or
alkenyl succinic anhydride is particularly suitable. In the case where
alkyl ketene dimer is used, the addition amount thereof can be small
since alkyl ketene dimer has a high sizing effect. However, alkyl ketene
dimer reduces friction coefficient of a surface of the recording medium,
and thus the surface of the recording medium becomes easy to slip.

Therefore, use of alkyl ketene dimer is not preferable in term of transfer
performance of the recording medium at the time of inkjet recording.
The addition amount of the internally adding sizing agent is 0.1 parts by
mass to 0.7 parts by mass with respect to 100 parts by mass of bone-dry
pulp, but it may be adjusted depending on the purpose.
The internal additives for use in the support are, for example,
conventional pigments as a white pigment. Examples of the white
pigment include- inorganic white pigments such as precipitated calcium
carbonate, heavy calcium carbonate (limestone powder), kaolin, clay, talc,
calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide,
zinc carbonate, satin white, aluminum silicate, silious earth, calcium
silicate, magnesium silicate, synthetic silica, aluminum hydroxide,
alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide,
and the like; organic pigments such as styrene plastic pigment, acrylic
plastic pigment, polyethylene, microcapsule, urea resin, melamine resin,
and the like. One of these may be used, or two or more of these may be
used in combination as the internal additive.
-Method for forming a barrier layer-
A method for forming a barrier layer on the support is not
restricted, but can be selected from a method for directly coating, a
method for coating on a temporally substrate, and then transferring to
the support, and a method for atomizing using a spray or the like.
Examples of the method for directly coating include a rollcoater method,
an air-knife coater method, a gate-roll coater method, a size-press
method, a shim-sizer method, a film transfer system such as rod-

metaling size press coater, a blade coater system by fountain or roll
application, and the like.
A drying treatment of the barrier layer can be performed, for
example, by using a hot drying hearth or a heat drum. Moreover, the
barrier layer may further be subjected to a surface treatment by using a
calender device, i.e. super calender, soft calender, gloss calender, or the
like, for the purpose of smoothing the surface, or increasing the strength
of the surface.
As mentioned earlier, the barrier layer for use in the present
invention can be disposed by coating. After the present inventors had
conducted numbers of studies, it was found that functions of a barrier
layer could be attained by polishing a surface of a conventional coated
paper for printing. This is probably because a thickness of a coat layer
of the conventional coated paper is reduced to a thickness of the barrier
layer suitable for the present invention by polishing, and functions as a
barrier layer are exhibited as a result of removing a resin layer present
on the outermost surface of the coating by polishing and exposing pores
presented inside to the surface.
Specific examples of the conventional coated paper include-
coated paper used for commercial printing, i.e. off-set printing, gravure
printing, and the like, such as art paper (A0 size, A1 size), A2 size coated
paper, A3 size coated paper, B2 size coated paper, lightweight coated
paper, finely coated paper, and the like.
Specific examples for commercial products of the art paper are:
Golden Cask Gloss N, Golden Cask GlossR40N, Golden Cask Super Art

N, Golden Cask Satin N, Golden Cask SatinR40N, Golden Cask Ultra
Satin N, Ultra Golden Cask Gloss N, and 1/2 Side Golden Cask Gloss
manufactured by Oji Paper Co., Ltd.; NPi Special Art, NPi Super Art,
NPi Super Dull, and NPi Dull Art manufactured by Nippon Paper Group,
Inc.; Utrillo Super Art, Utrillo Super Dull, and Utrillo Premium
manufactured by Daio Paper Corporation." High-quality Art A, Special
Mitsubishi Art, Super Mat Art A, and High-quality Dull Art A
manufactured by Mitsubishi Paper Mills Limited; Snow Grouse Super
Art A, Snow Grouse Super Art MN, Snow Grouse Special Art, and Snow
Grouse Dull Art N manufactured by Chuetsu Pulp & Paper Co., Ltd.; and
the like.
Specific examples for commercial products of the A2 size coated
paper are: OK Top Coat + (Plus), OK Top Coat S, OK Casablanca, OK
Casablanca V, OK Trinity, OK Trinity NaVi, New Age, New Age W, OK
Topcoat Matt N, OK Royal Coat, OK Topcoat Dull, Z coat, OK Kasahime,
OK Ksao, OK Ksao Satin, OK Topcoat+, OK Non-wrinkle, OK Coat V, OK
Coat N Green 100, OK Mat Coat Green 100, New Age Green 100, and Z
Coat Green 100 manufactured by Oji Paper Co., Ltd.; Aurora Coat, Sea
Roar Mat, Imperial Mat, Silver Diamond, Recycle Coat 100, and Recycle
Mat 100 manufactured by Nippon Paper Group, Inc.; Mu Coat, Mu Coat
White, Mu Mat, and White Mue Mat manufactured by Hokuetu Paper
Mills, Ltd.; Snow Grouse Coat N, Regina Snow Grouse Coat 100, Snow
Grouse Mat Coat N, and Regina Snow Grouse Mat 100 manufactured by
Chuetsu Pulp & Paper Co., Ltd.; Peal Coat, White Peal Coat N, New V
Mat, White New V Mat, Peal Coat REW, White Peal Coat NREW, New V

Mat REW, and White New V Mat REW manufactured by Mitsubishi
Paper Mills Limited," and the like.
Specific examples for commercial products of the A3 size coating
(lightweight coating) paper are: OK Coat L, OK Royal Coat L, OK Coat
LR, OK White L, OK Royal Coat LR, OK Coat L Green 100, and OK Mat
Coat L Green 100 manufactured by Oji Paper Co., Ltd.; Easter DX,
Recycle Coat L100, Aurora L, Recycle Mat L100, and Energy
White manufactured by Nippon Paper Group, Inc.,' Utrillo Coat L, and
Matisse Coat manufactured by Daio Paper Corporation," Hi-Alpha, Alpha
Mat, (N) Kinmari L, and Kinmari HiL manufactured by Hokuetu Paper
Mills, Ltd.; N Peal Coat L, N Peal Coat LREW, and Swing Mat REW
manufactured by Mitsubishi Paper Mills Limited; Super Emine, Emine,
and Shaton manufactured by Chuetsu Pulp & Paper Co., Ltd.; and the
like.
Specific examples for commercial products of the B2 size coating
(middleweight coating) paper are: OK Middleweight Coat, (F) MCOP, OK
Astro Gloss, OK Astro Dull, and OK Astro Mat manufactured by Oji
Paper Co., Ltd.; King O manufactured by Nippon Paper Group, Inc.; and
the like.
Specific examples for commercial products of the finely coated
paper are: OK Royal Light S Green 100, OK Ever Light Coat, OK Ever
Light R, OK Ever Green, Clean Hit MG, OK Fine Coating Super Eco G,
Eco Green Dull, OK Fine Coating Mat Eco G100, OK Star Light Coat,
OK Soft Royal, OK Bright, Clean Hit G, Yamayuri Bright, Yamariyu
Bright G, OK Aqua Light Coat, OK Royal Light S Green 100, OK Bright

(Rough/ Gloss), Snow Mat, Snow Mat DX, OK Kasahime, and OK
Kasayuri manufactured by Oji Paper Co., Ltd.; Pirene DX, Pegasus
Hyper 8, Aurora S, Andes DX, Super Andes DX, Space DX, Seine DX,
Special Gravure DX, Pegasus, Silver Pegasus, Pegasus Harmony, Green
Land DX100, Super Green Land DX100, Energy Soft,
Energy Light, and EE Henry manufactured by Nippon Paper Group, Inc.;
Kant Excel, Excel Super B, Excel Super C, Kant Excel Bal, Utrillo Excel,
Heine Excel, and Dante Excel manufactured by Daio Paper Corporation;
Cosmo Ace manufactured by Nippon Daishowa Paperboard Co., Ltd.;
Semi-Upper L, High-Beta, High-Gamma, Shiromari L, Hamming, White
Hamming, Semi-Upper HiL, and Shiromari HiL manufactured by
Hokuetu Paper Mills, Ltd.; Ruby Light HREW, Peal Soft, and Ruby Light
H manufactured by Mitsubishi Paper Mills Limited; Shaton, Ariso, and
Smash manufactured by Chuetsu Pulp & Paper Co., Ltd.; Star Cherry,
and Cherry Super manufactured by Marusumi Paper Co., Ltd.; and the
like.
The conventional formula for a coating layer of the commercial
recording paper generally shown in various documents is, for example,
mixing 10 parts to 15 parts by a binder, e.g. a resin, emulsion, starch,
and the like, with 100 parts of an inorganic pigment, e.g. kaolin, calcium
carbonate, and the like. Analyzing the condition of the pigment present
in the coating layer, specifically the density deviation of the pigment
within the coating layer, the following possible questions can be
considered" (1) a clear layer formed on the outermost layer of the coated
film, when a coating liquid is used, and (2) the binder component is

penetrated into a base paper, and thus a density distribution is
dissymmetrical between the upper layer and the bottom layer.
Regarding the problem (1), the present inventors studied the
publications of this field (publication related to glossiness or the like of a
coated paper). However, it seemed that this problem had not been
actively discussed in the art. It is assumed that the coating liquid of the
coating layer contains a low mixing rate of the resin compared to general
coating liquid, the enough amount of the resin is not contained to
precipitate in the surface, and thus a clear layer or the like is not easily
formed.
In the occasion of the discussion with other engineers in the field
of commercial coated paper, there were people who believed that the
binder for use in the commercial coated paper needed to be added at a
minimum amount, since some believed that the functions of the binder
were to prevent pealing of a layer at the time of printing, and to
maintain just enough strength to prevent flaking off of the powder at the
time of cutting the paper, and a coating process was likely to be affected
if the addition amount of the resin was increased.
With regard to the problem (2), though phenomena such that a
ratio of the resin in the actual coating layer becomes lower than the rat
of the resin in the coating liquid in the process of penetrating the resin of
the coating liquid into the base paper, and a layer is formed between the
coating layer and the base layer, no case has been recognized (even in
publications) regarding the generation of deviation within the layer itself.
However, there is a case that a resin-rich layer is formed at interfere

between the coating layer and the base paper. In this case, it is
assumed that the bottom layer has higher density of the resin.
A method for polishing an outermost surface of the coating layer
is, for example, a method which uses a sand paper or wrapping paper for
polishing, a method which uses a wire-brush for polishing, a method
which uses a polishing roller, or polishing endless belt for polishing, a
method which uses sand blast for polishing, or the like. However,
examples of the polishing method are not limited to those listed above.
The polishing treatment can be performed just before drying, or
either before or after conducting a calendering treatment in the process
of producing a coat paper. Alternatively, the polishing treatment may
be curried out by appropriately arranging a polishing process after a
coating process, for example, after a slitting process, or after a wrapping
process. Moreover, the polishing treatment can be performed by users
by using a polishing device before conducting printing. It is also
possible to integrate the polishing device into a printer, and to perform
the polishing treatment every time printing is conducted.
For the polishing treatment, an entire surface of a recording
medium may be polished, or only an area where an inkjet recording is
performed may be selectively polished.
For example, off-set printing or gravure printing is previously
performed on the general recording medium exemplified above, the
recording medium is then subjected to the polishing treatment at where
inkjet recording is performed, and inkjet recording is actually conducted
on a part of the recording medium where previously polished.

According to this method, a hybrid printing, which have
conventionally been performed by using both an inkjet recording medium
and a general recording medium, can be performed by using only a
general recording medium, and a unification of a recording medium can
be realized between general printing and inkjet printing. In addition,
printing of address, which is difficult to be done by general printing, can
be performed by inkjet printing.
The polishing device may be integrated into a unit of a printer, or
be independently prepared as a separate unit.
Moreover, a recording medium of the present invention can be
replaced with a special coated paper, provided that the coated paper
satisfies the requirements defined in the present invention. Especially,
a coated paper which has high air permeability of a coating layer itself
can be used in the present invention. Examples of such coated paper
having high air permeability are: some coated paper for
electrophotography, coated paper for gravure printing, and the like.
Specific examples thereof include POD Gloss Coat manufactured by Oji
Paper Co., Ltd., FL Gravure manufacture by Nippon Paper Group, Inc.,
Ace manufactured by Nippon Paper Group, Inc., and the like. The
coating layer of these coated papers has large number of pores, and thus
these coated papers can be used as a replacement of the recording
medium having the barrier layer of the present invention.
[Ink for inkjet recording]
The ink for inkjet recording has extremely high permeability, and
a surface tension of 20 mN/m to 35 mN/m at 25°C, preferably 23 mN/m to

33 mN/n at 25°C. If the surface tension of the ink is less than 20 mN/n,
the ink attached to the surface of the nozzle head cannot be completely
removed after head-wiping operation, and thus it may adversely affect
the reliability of the head after leaving for a long period. If the surface
tension of the ink is more than 35 mN/m, the permeability of the ink to a
recording medium may be degraded. As a result of this, dots formed
from the ink droplet may not have sufficient wet-speadability, and the
effects for reducing the occurrence of beading may be reduced.
Moreover, the ink for inkjet recording has a viscosity of 5 mPa-s
or more, and preferably ranging from 5 mPa-s to 20 mPa•s at 25°C. If
the viscosity is less than 5 mPa-s, it may adversely affect to the medium,
in terms of occurrence of beading, or transfer ability such as the
occurrence of cockling. If the viscosity is more than 20 mPa•s, the
viscosity is largely increased at the low temperature, such as 10°C, and it
may adversely affect ejection reliability of the head, reliability for nozzle
clogging.
-Coloring agent-
The coloring agent for use in the ink of the present invention is,
for example, a hydrophobic dye, a pigment, or the like. The hydrophobic
dye is a dye which has insolubility or poor solubility to water, but is
soluble to an organic solvent. Examples of the hydrophobic dye include
oilsoluble dyes, dispersible dyes, and the like. These hydrophobic dyes
can be used as a polymer emulsion wherein the hydrophobic dye is
contained in the polymer. Considering its adsorption and/or easiness of
encapsulation, the oil-soluble dye and the dispersible dye are preferably

used, but the pigment is particularly preferable in terms of the light
fastness of the obtained image.
The above-mentioned expression "the hydrophobic dye is
contained in the polymer" means both the conditions of the hydrophobic
dye being encapsulated in polymer fine particles, and the hydrophobic
dye being attached to the surface of the polymer fine particles. Here,
not all of the coloring agent contained in the ink need to be encapsulated
in or attached to the polymer fine particles. The coloring agent can be
dispersed in the emulsion, provided that it does not adversely affect the
effects of the present invention. The coloring agent can be selected
without any restriction, as long as it has insolubility or poor solubility to
water, and is absorbed with a polymer. In the present specification, the
term "insolubility to water", or "poor solubility to water" defines the
condition such that 100 parts by mass of 20°C water dissolves no more
than 0.1 parts by mass of the coloring agent. Here, the term "dissolve"
means that the separation or precipitation of the coloring agent is not
observed with naked eyes in the surface or bottom part of the solution.
Examples of the pigment include a black pigment, and a color
pigment. Examples of the black pigment include carbon black and the
like. Examples of the color pigment include anthraquinone,
phthalocyanine blue, phthalocyanine green, diazo, monoazo, pyranthrone,
perylene, heterocyclic yellow, quinacridone, (thio)indigo, and the like.
Examples of phthalocyanine blue include cupper phthalocyanine blue
and a derivative thereof (including C.I. Pigment Blue 14). Examples of
quinacridone include: C.I Pigment Orange 48 and 49; C.I. Pigment Red

122, 192, 202, 206, 207, and 209; and C.I. Pigment Violet 19 and 42.
Examples of anthroquinone include Pigment Red 43, 194 (perynone red),
216 (pyranthrone bromide red), and 226 (pyranthrone red). Examples of
perylene include: C.I. Pigment Red 123 (vermilion), 149 (scarlet), 179
(marron), and 190 (red); C.I. Pigment Violet; CI. Pigment Red 189
(yellow shaded red), and 224. Examples of thioindigo include; C.I.
Pigment Red 86, 87, 88, 181, and 198; CI. Pigment Violet 36 and 38.
Examples of heterocyclic yellow include CI. Pigment Yellow 117 and 138.
Other suitable examples of the pigment were listed in "The Color Index,
The Society of Dyers and Colorists, 1982".
The pigment for use in the ink of the present invention may be a
pigment having directly or, via another group of atoms, at least one
hydrophilic group on the surface thereof. Such the pigment can be
stably dispersed without the assistance of a dispersant. The pigment
wherein a hydrophilic group is introduced onto the surface thereof is
preferably an ionic pigment, more preferably the one anionicly or
cationicly charged.
Examples f the anionic hydrophilic group include the groups
expressed as follows" COOM, SO3M, -PO3HM, PO3M2, SO2NH2, and-
SO2NHCOR (note that M denotes one selected from the group consisting
of a hydrogen atom, alkali metal, ammonium, and organic ammonium,
and R denotes one selected from a C1-12 alkyl group, a substituted or
unsubstituted phenyl group, and a substituted or unsubstituted naphthyl
group). Among them, the pigment having COOM, or -SO3M bonded
onto the surface thereof is preferable. The method for obtaining the

anioicly charged pigment is, for example, a method wherein a pigment is
subjected to an oxidation treatment using sodium hypochlorite, a method
wherein a pigment is subjected to a sulfonation treatment, a method
wherein the pigment is reacted with a diazonium salt, or the like, but not
limited thereto.
A hydrophilic group bonded to a cationicly charged color pigment
is, for example, a quaternary ammonium group, or the like.
As the pigment for use in the ink of the present invention, a
dispersion having a pigment dispersed in an aqueous medium with
assistance of a dispersant. The dispersant is preferably one selected
from the conventional dispersants used for controlling pigment
dispersion.
Specific examples of the dispersant include polyacrylic acid,
polymethacrylic acid, acrylic acid-acrylonitrile copolymer, vinyl acetate-
acrylic ester copolymer, acrylic acid-alkyl acrylate copolymer, styrene-
acrylic acid copolymer, styrene-methacrylic acid copolymer, styrene-
acrylic acid-alkyl acrylate copolymer, styrene-methacrylic acid-alkyl
acrylate copolymer, styrene-α-methylstyrene-acrylic acid copolymer,
styrene-a-methylstyreneacrylic acid-alkyl acrylate copolymer, styrene-
maleic acid copolymer, vinyl naphthalenemaleic acid copolymer, vinyl
acetateethylene copolymer, vinyl acetate-fatty acid vinyl ethylene
copolymer, vinyl acetate-maleic ester copolymer, vinyl acetate-crotonic
acid copolymer, vinyl acetate-acrylic acid copolymer, and the like.
The nonionic or anionic activating dispersant for dispersing the
pigment can be appropriately selected depending on the pigment for use

or components of the ink. Examples of the nonionic surfactant as the
dispersant include: polyoxyethylenealkylether such as
polyoxyethylenelaurylether, polyoxyethylenemryistylyether,
polyoxyethylenecetylether, polyoxyethylenestrearylether,
polyoxyethyleneoleylether, or the like; polyoxyethylenealkylphenylether
such as polyoxyethyleneoctylphenylether,
polyoxyethylenenonylphenylether, or the like; polyoxyethylene-cr
naphthylether expressed by the following general formula l;
polyoxyethylenemnostrearylphenylether;
polyoxyethylenedistylylphenylether; polyoxyethylenealkylnaphthylether;
polyoxyethylenemonostyrylnaphthylether;
polyoxyethylenedistyrylmaphthylether; polyoxyethylene-
polyoxypropylene block polymer; and the like. Also examples include a
surfactant which is at least one selected from the one listed above
wherein a part of polyoxyethylene is substituted with polyoxypropylene,
a surfactant which is a compound having an aromatic ring, e.g.
polyoxyethylenealkylphenylether, is condensed with formaldehyde

In the general formula 1, R1 denotes a C1-20 alkyl group, aryl
group, or aralkyl group group. L denotes 0 or an integer ranging from 1-
7. n denotes an integer ranging from 20200, preferably 20-100, more

preferably 3050.
Examples of the C1-20 alkyl group for RL include methyl group,
ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group,
t-butyl group, n-pentyl group, i-pentyl group, cyclopentyl group, n-hexyl
group, i-hexyl group, cyclohexyl group, n-heptyl group, i-heptyl group, rr
octyl group, i-octyl group, n-nonyl group, i-nonyl group, n-decyl group, i-
decyl group, n-undecyl group, rundecyl group, n-dodecyl group, i-dodecyl
group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cycloheptyl
group, cyclooctyl group, and the like.
Examples of the aralkyl group for RL include benzyl group,
phenethyl group, 2-methylbenzyl group, 3-methylbenzyl group, 4-
methylbenzyl group, and the like.
The HLB value of the nonionic surfactant is preferably the range
of 12 or more but 19.5 or less, more preferably the range of 13 or more
but 19 or less. If the nonionic surfactant has HLB value of less than 12,
the surfactant does not have good compatibility to the dispersion medium,
and thus dispersion stability is lowered. If the nonionic surfactant has
HLB value of more than 19.5, the surfactant does not have good
compatibility to the pigment, and thus dispersion stability is lowered.
Examples of the anionic surfactant include
polyoxyethylenealkylether sulfate, polyoxyethylenealkylphenylether
sulphate, polyoxyethylenemonostyrylphenylether sulphate,
polyoxyethylenedistyrylphenylether suphate, polyoxyethylenealkylether
phosphate, polyoxyethylenealkylphenylether phosphate,
polyoxyethylenemonostyrylphenylether phosphate,

polyoxyethylenedistyrylphenylether phosphate,
polyoxyethylenealkylether carbonate, polyoxyethylenealkylphenylether
carbonate, polyoxyethylenemonostyrylphenylether carbonate,
polyoxyethylenedistyrylphenylether carbonate, naphthalene sulfonate -
formaldehyde condensation product, melanin sulfonate-formaldehyde
condensation product, dialkylsulfosuccinate, alkyl disulfosuccinate,
polyoxyethylenealkyl disulfosuccinate, alkylsulfoacetate, aolephine
sulfonate, alkylbenzenesulfonate, alkylnaphthalene sulfonate, alkyl
sulfonate, N-acyl amino acid salt, acyl peptide, soap, and the like.
Among these, sulfate or phosphate of polyoxyethylenealkylether,
polyoxyethylenealkylphenylether, and
polyoxyethylenedistyrylphenylether are particularly preferable.
The content of the surfactant as.the dispersant is preferably 10%
by mass to 50% by mass relative to the amount of the pigment. If the
content of the dispersant is less than 10% by mass, storage stability of
the dispersed pigment and ink is lowered, or extremely long time is
required for dispersing the pigment. If the content of the dispersant is
more than 50% by mass, the viscosity of the ink becomes excessively high,
and thus ejection stability becomes lowered.
Moreover, a resin-coated coloring agent is also used as the
coloring agent. The resin-coated coloring agent is precisely explained
hereinafter.
The resin-coated coloring agent is formed of polymer emulsion
including polymer fine particles which contain the coloring agent having
insolubility or poor solubility to water. The expression "polymer fine

particles which contain, the coloring agent " means both the conditions of
the coloring agent being encapsulated in polymer fine particles, and the
coloring agent being attached to the surface of the polymer fine particles.
Here, not all of the coloring agent contained in the ink need to be
encapsulated in or attached to the polymer fine particles. The coloring
agent can be dispersed in the emulsion, provided that it does not
adversely affect the effects of the present invention. The coloring agent
can be selected without any restriction, as long as it has insolubility or
poor solubility to water, and is absorbed with a polymer. In the present
specification, the term "insolubility to water" or "poor solubility to water"
defines the condition such that 100 parts by mass of 20°C water dissolves
no more than 0.1 parts by mass of the coloring agent. Here, the term
"dissolve" means that the separation or precipitation of the coloring
agent is not observed with naked eyes in the surface or bottom part of
the solution.
Examples of the coloring agent include a hydrophobic dye such as
an oil-soluble dye, dispersible dye or the like, the pigment, and the like.
Considering its adsorption and/or easiness of encapsulation, the oil-
soluble dye and the dispersible dye are preferably used, but the pigment
is particularly preferable in terms of the light fastness of the obtained
image.
Examples of the hydrophobic dye are listed below.
Examples of the oil-soluble dye include each product number of
C.I. Solvent Black, C.I. Solvent Yellow, C.I. Solvent Red, C.I. Solvent
Violet, CI. Solvent Blue, C.I. Solvent Green, and C.I. Solvent Orange.

These are available from Orient Chemical Industries, Ltd., BASF Japan
Ltd., and the like.
Examples of the dispersible dye include each product number of
C.I. Disperse Yellow, C.I. Disperse Orange, C.I. Disperse Red, C.I.
Disperse Violet, C.I. Disperse Blue, and C.I. Disperse Green. Among
these, preferable dyes are C.I. Solvent Yellow 29 and 30 for yellow, C.I.
Solvent Blue 79 for cyan, C.I. Solvent Red 18 and 49 for magenta, and
C.I. Solvent Black 3 and 7 and nigrosin black dye for black. Note that
examples of the hydrophobic dye are not necessarily limited to these
listed above.
The coloring agent for use in the present invention is preferably
dissolved in an organic solvent such as a ketone solvent at a rate of 2g/L
or higher, more preferably at a rate of 20g/L to 600g/L, in view of
efficient impregnation into polymer fine-particles. Examples of a
polymer comprised of the polymer emulsion include vinyl polymer,
polyester polymer, polyurethane polymer, and the like. Especially, vinyl
polymer and polyester polymer are preferably used, and their specific
examples are the polymers disclosed in JP-A Nos, 200053897, and 2001-
139849.
The content of the coloring agent is preferably 10 parts by mass
to 200 parts by mass, more preferably 25 parts by mass to 150 parts by
mass with respect to 100 parts by mass of the polymer. The average
particle diameter of the polymer fine particles containing the coloring
agent is preferably 0.16 µm or less in the ink.
The solids content of the polymer fine particles is preferably 8%


by mass to 20% by mass, more preferably 8% by mass to 12% by mass in
the ink.
-Surfactant-
The present invention achieves the significant improvements in
wettability, and permeability to the recording medium by adding a
surfactant, especially a fluorochemical surfactant having a certain
structure. This particular fluorochemical surfactant having a certain
structure has characteristics those dissimilar to the ones of the
conventional fluorochemical surfactant. The conventional
fluorochemical surfactant tends to have high foamability, and most of the
available conventional flurochemical surfactants are prone to form
bubbles. It has been known in the art that this foamability adversely
affects loading ability of the ink or ejecting stability of the ink. However,
the fluorochemical surfactant having a certain structure for use in the
present invention maintains its foamability very low, and thus the
obtained ink has excellent loading ability, ejecting stability, and safety.
In addition, the obtained ink has high coloring ability and uniform
dispersibility of the coloring agent on a recording medium for inkjet
recording for use in the present invention. Because of this particular
effect in permeability, occurrences of beading are prevented, and thus
excellent images can be formed. The precise mechanisms thereof have
not yet been completely found out, but it is assumed that the
fluorochemical surfactant having a certain structure has excellent
leveling performance, and exhibits a high effect in leveling a surface
tension at an interfere between air and liquid, due to its structure.

Moreover, it is understood that this characteristic bring a high effect in
preventing to form bubbles, and this high leveling performance on the
recording medium leads an effect in uniformly dispersing the coloring
agent, and uniformly wetting and spreading a diameter of a picture
element, and as a result, the occurrence of beading is greatly inhibited.
Based on these understandings, it is assumed that prints of high quality,
excellent density, glossiness, and image reliability, which is similar to
those of commercial printing, can be attained at low cost, by combining
the recording medium for inkjet recording described in the present
specification and the pigment ink of inkjet recording described in the
present specification. Moreover, from the same reasons, there can be
provided the desirable ink for inkjet recording, ink set for inkjet
recording, ink media set for inkjet recording, ink cartridge, inkjet
recording method, and inkjet recording apparatus having reliability for
preventing clogging, and storage stability.
The compound expressed by the following structural formula 1 is
a surfactant particularly suitable for use in the present invention:
Structural formula 1

In the structural formula 1, each of R1 and R2 denotes either a

hydrogen atom or a group containing a fluorine atom, each of R3 and R4
denotes a group containing a fluorine atom, and each of e, m, p, q, and r
denotes an integer.
Other than using the fluorochemical surfactant expressed by the
structural formula 1 alone, the florochemical surfactant expressed by the
structural formula 1 can be used in combination with the following
fluorochemical surfactants in the present invention. Examples of such
fluorochemical surfactants include perfluoroaltylsulfonate,
perfluoroalkylcarboxylate, perfluoroalkylphosphate,
perfluoroalkylethyleneoxide adducts, perfluoroalkylbetaine,
perfluoroalkylamineoxide compounds, and the like. Examples of the
commercially available products of such fluorochemical surfactants
include: Surflon S-111, S112, S113, S-121, S131, S132, S141, and S-
145 (msnufactured by Asahi Glass Co., Ltd.); FLUORAD FC 93, FC-95,
FC-98, FC-129, FC-135, FC170C, FC-430, FC-431, and FC4430
(manufactured by Sumitomo 3M Limited); Megafack F-470, F-1405, and
F-474 (manufactured by Dainippon Ink & Chemicals Inc.); Zonyl FS-300,
FSN, FSN-100, FSO (manufactured by DuPont Kabushiki Kaisha);
EFTOP EF-351, EF-352, EF-801, and EF-802 (manufactured by JEMCO
Inc). Among them, Zonyl FS-300, FSN, FSN-100, and FSO
(manufactured by DuPont Kabushiki Kaisha) are particularly preferable
in view of excellent reliability and improved color development.
Other examples of the surfactants which can be used in
combination with the above-mentioned fluorochemical surfactant include
surfactants such as polyoxyethylenealkyletheracetate,

dialkylsulfosuccinate, polyoxyethylenealkylether,
polyoxyethylenealkylphenylether, a polyoxyethylene-polyoxypropylene
block copolymer, polyoxyethylenealkylester, polyoxyethylene sorbitan
fatty acid ester, acetylene glycol, and the like. Specifically, by using
polyoxyethylenealkyletheracetate and/or dialkylsulfosuccinate having a
C5-7 branched alkyl chain, the wettability is improved towards normal
paper. These surfactants listed above can be stably present in the ink of
the present invention without adversely affecting the dispersing
condition of the ink.
-Penetrating agent-
The penetrating agent for use in the present invention is C7-11
polyol, or the like. Examples of C7-11 polyol include 2ethyl-l,3-
hexandiol, 2,2,4-trimethyl-l,3-pentandiol, and the like. The content of
the penetrating agent is preferably 0.1% by mass to 20% by mass, more
preferably 0.5% by mass to 10% by mass. In the case where the content
of the penetrating agent is less than the above-mentioned range, the
penetration of the ink into the paper may be decreased, and this may
cause soiling on the paper as a result of the friction caused by a roller at
the time of transferring the paper, or may cause soiling on the
transferring belt at the time of reversing the side of the paper for the
purpose of double-side printing. Therefore, such ink cannot be used for
high-speed printing, or double-side printing. In the case where the
content is more than the above-mentioned range, a diameter of printed
dots becomes excessively large, and thus line width of character becomes
wide or image definition is lowered.

Solid moisture retainer-
The second embodiment of the ink of the present invention
contains dipeptide as a solid moisture retainer, and by adding the
dipeptide which is at least one selected from the group consisting of
alanyl glutamine, glycyl glutamine, bisalanylcystine, and
bisglycylcystine to the ink, all of the reliability for preventing clogging,
the reliability for transferring a recording medium, e.g. prevention of
beading or cockling, and the image reliability are attained at the same
time.
The solid moisture retainer defines a compound which has
moisture retaining functions, is a solid water-soluble compound at a
room temperature of 25°C, is dissolved or partially dissolved in the
vehicle of the ink, and does not adversely affect the dispersion stability of
the pigment (not causing aggregation of the pigment) contained in the
ink.
Among dipeptide used as the solid moisture retainer, alanyl
glutamine has extremely high water-solubility at 20°C or lower compared
to conventional amino acids, and does not adversely affect the dispersion
stability of the pigment at the time being added to the ink. Moreover,
alanyl glutamine can be added to the ink at 1 part by mass to 20 parts by
mass, preferably 3 parts by mass to 10 parts by mass in solids content.
In the case where the solids content is less than 1 part by mass in the ink,
the effect of preventing clogging cannot be attained. In the case where
the solids content is more than 20 parts by mass, the viscosity of the ink
becomes excessively high, and thus it affects stability for preventing

clogging. In the present invention, dipeptide contributes the stability of
the ink for preventing clogging. This is probably because dipeptide has
high water-solubility, is stably dissolved in the ink due to its water-
solubility, and thus does not adversely affect the dispersion stability of
the pigment as the coloring agent. Moreover, dipeptide is present in the
ink while having weak compatibility to the pigment, and thus it is
assumed that dipeptide also functions as a dispersion stabilizer in the
ink. Dipeptide also has an effect in retaining moisture. For example,
alanine is a natural moisture retaining substance present in a horny
layer of humans, glutamine is a substance easily absorbed in cells of
humans, and alanyl glutamine which is comprised both alanine and
glutamine is a highly safe moisture retaining substance widely used for
cosmetic products, and medicines of skins for external application. It is
assumed that these high moisture retaining abilities of dipeptide
contribute to a stability of the ink for preventing clogging in combination
with its water-solubility contributing to the pigment dispersion.
Specifically, water retaining ability of the ink is maintained even the ink
is present adjacent to the nozzle, and aggregations of the pigments are
prevented at the time of drying. As a result, a significantly high
reliability of the ink for preventing clogging can be exhibited. With
regard to the image reliability, dipeptide contributes to improve fixing
ability of the ink of the present invention having low absorption ability to
the recording medium, to lower occurrence of beading, and to prevent
curling or cockling at the time of printing as a moisture content of the
ink is relatively reduced. This is because dipeptide can be added to the

ink at a large amount in solids content, without adversely affecting the
dispersion condition of the pigment and penetration of the ink into low
price recording mediums, and a moisture content of the ink can be
relatively reduced. It is assumed that significant effects are exhibited
against the problems to be solved in the present invention, by using the
particular ink and the particular recording medium in combination in
the present invention.
The above-mentioned expression "a moisture content of the ink is
relatively reduced" means a relative moisture content of the ink which
dipeptide is not included is reduced inversely proportional to the solids
content of dipeptide to be added, by adding dipeptide to the ink.
-Water-dispersible resin-
The water-dispersible resin for use in the first embodiment of the
ink of the present invention is preferably at least one selected from the
group consisting of polyurethane resin emulsion, and acryl-silicone resin
emulsion. These may be used in combination. At the time of using the
water-dispersible resin as a raw material in course of preparing the ink,
or after preparing the ink, the water-dispersible resin is present as an oil
in water emulsion.
In the case where at least one of the above-listed water-
dispersible resins is used, the solids content of the emulsion in the ink is
1% by mass to 40% by mass, preferably 1% by mass to 20% by mass.
Examples of the polyurethane resin emulsion include the one
wherein a relatively hydrophilic polyurethane resin is externally added
with an emulsifier to thereby emulsified, and a self-emulsified emulsion

wherein a functional group served as an emulsifier is introduced into a
resin by copolymerization or the like. An anionic self-emulsified
polyurethane resin emulsion always has excellent dispersion stability,
considering the combination with the pigments selected for use in the
present invention. The anionic self-emulsified polyurethane resin
emulsion has preferably an ether type of polyurethane resin, rather than
polyester or polycarbonate type thereof, in terms of fixing ability to the
pigment and dispersion stability. Although specific reasons have not yet
been known, the non-ether type thereof tends to have weak solvent
resistance, and tends to cause aggregation or increase in the viscosity
when the ink is stored at a high temperature.
An average particle diameter of the ether type of polyurethane
resin emulsion is 300 nm or less, preferably 100 nm or less, more
preferably 80 nm or less. By controlling the average particle diameter
specifically 100 nm or less, a reliability of the inkjet recording apparatus,
e.g. ink ejecting stability after storing for a long period, is improved.
The glass transition temperature of the ether type of
polyurethane resin emulsion is preferably in the range of -50°C to 150°C,
more preferably in the range of -10°C to 100°C. In the case where the
glass transition temperature thereof is more than 150°C, a film formed
with the ether type of polyurethane resin emulsion becomes hard like a
glass, but the pigment particles and the ether type of polyurethane resin
emulsion come to an impact with a recording medium at the same time
at the time of printing, and thus obtained image has relatively low
abrasion resistance. In the case where the glass transition temperature

is 150°C or less, a film formed with the ether type of polyurethane resin
emulsion is soft, and rubber like, but has excellent abrasion resistance.
If the glass transition temperature is less than -50°C, the film however
becomes excessively soft, and the abrasion resistance is lowered.
Therefore, it was found that the preferable range of the glass transition
temperature was from -50°C to 150°C in view of the abrasion resistance
of the print. In the present invention, the glass transition temperature
of the resin can be measured either by a differential scanning calorimeter
(DSC) or thermomechanical analysis (TMA).
The minimum film forming temperature of the ether type of
polyurethane resin emulsion is preferably a room temperature or lower,
more preferably 25°C or lower. It is preferred that a film formation of
the ether type of polyurethane resin emulsion is carried out at a room
temperature or lower, especially at 25°C or lower, since the bonding to
the fibers in the paper is automatically performed without proceeding
any special treatment such as heating or drying.
The minimum film forming temperature (MFT) is defined as a
minimum temperature to form a transparent continuous film when an
aqueous emulsion particles obtained by dispersing the ether type of
polyurethane emulsion particles in water is thinly coated onto a metal
plate such as aluminum and the temperature is rose so as to form a
transparent continuous film.
The aeryl-silicone resin emulsion for use in the present invention
is explained hereinafter.

Examples of the acryl-silicone resin emulsion include silicone-
modified acrylic resin emulsion which is obtained by polymerizing acrylic
monomer and a silane compound in the presence of an emulsifier.
Examples of the acrylic monomer include: acrylic ester monomers
such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl
acrylate, 2-hydroxyethyl acrylate, acrylyl morpholine, N,N'-
dimethylaminoethyl acrylate, and the like; methacrylic ester monomers
such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-
ethylhexyl acrylate, 2-hydroxyethyl methacrylate, N,N'-
dimethylaminoethyl mathacrylate, and the like; amide acrylate such as
N-methylol acrylamide, methoxymethylacrylamide, and the like;
carboxylic acid containing monomers such as maleic acid, fumaric acid,
itaconic acid, acrylic acid, methacrylic acid, and the like.
Examples of the emulsifier include alkylbenzenesulfonic acid and
their salt, dialkylsulfosuccinic ester and their salt,
alkylnaphthalenesulfonic acid and their salt, alkylnaphthalenesulfonic
acid salt formalin condensates, higher fatty acid salt, higher fatty acid
ester sulfonic acid salt, ethylenediamine polyoxypropylene-
polyoxyethylene condensates, sorbitan fatty acid ester and their salt,
aromatic and aliphatic phosphoric acid ester and their salt,
dodecylbenzenesulfonate, dodecylsulfate, laurylsulfate,
dialkylsulfosuccinate, polyoxyethylenealkylphenylethersulfate,
polyoxyethynealkylpropenylphenylethersulfate,
alkylphenyletherdisulfonate, polyoxyethylenealkylphosphate,
polyoxyethylenealkyletheracetate, polyoxyethylenelanoline alcohol ether,

polyoxyethylenelanoline fatty acid ester, laurylalcohol ethoxylate, lauryl
ether sulfuric ester salt, lauryletherphosphoric ester, sorbitan fatty ester,
fatty diethanolamide, naphthalenesulfonic acid formalin condensates,
and the like. Examples of the salt include sodium, ammonium, and the
like.
As the emulsifier, a reactive emulsifier having an unsaturated
double bond may be used in the present invention. Examples of the
reactive emulsifier include commercially available Adekalia soap SE, NE,
PP (manufactured by Adeka Corporation), LATEMUL S-180
(manufactured by Kao Corporation), ELEMINOL JS-2, ELEMINOL RS-
30 (manufactured by Sanyo Chemical Industries, Ltd.), and Aquaron RN-
20 (manufactured by Darichi Kogyo Seiyaku Co., Ltd.)
Examples of the silane compound include tetramethoxysilane,
methyltrimethoxysilane, dimethyldimethoxysilane,
phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane,
methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane,
diphenyldiethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane,
decyltrimethoxysilane, decyltriethoxysilane,
trifluoropropyltrimethoxysilane, and the like.
Monomers generally known as silane coupling agents may be
used as the silane compound, examples of which monomers include
vinyltrichlorsilane, vinyltrimethoxysilane, vinyltriethoxysilane,
p-styryltrimethoxysilane, 3methacryloxypropylmethyldimethoxysilane,
3-methacryloxypropyltrimethoxysilane,
3-methacryloxypropylmethyldiethoxysilane,

-methaayloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane,
N-2(aminoethyl) 3-ammopropylmethyldimethoxysilane,
N-2(aminoethyl) 3-aminopropyltrimethoxysilane,
N-2(aminoethyl) 3-ammopropyltriethoxysilane,
3-ammopropyltrimethoxysilane, 3-ammopropyltriethoxysilane,
3-triethoxysnyl-N-(l3-dimethyl-butylidene)propylamine,
N^henyl-3-aminopropyltrimethoxysilaiie,
N-(vinyIbenzyl)_2-aminoethyl-3-aminopropyltrimethoxysilane hyrochloric
acid salt, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane,
3-meiraptopropyhnethyldimethoxysilane, 3-mercaptopropyltrxmethoxysilane,
bis(triethoxysilylpropyl)tetrasulfide, 3isocyanate propyltriethoxysilane, and
the like.
The hydrolyzable silyl group refers to a silyl group containing a
hydrolyzabile group in the present invention. Examples of the
hydrolyzable group include alkoxy, mercapto, halogen, amide, acetoxy,
amino, isopropenoxy groups, and the like.
The silyl group is hydrolyzed and becomes a silanol group, which
is dehydrated and condensed, and a siloxane bond generated. In the
present invention, the hydrolyzable silyl group in the silicone modified
acrylic resin is hydrolyzed via the polymerization reaction and
disappears, so there is no hydrolyzable silyl group in the silicone
modified acrylic resin. If the hydrolyzable silyl group remains, when it
is used in making the recording ink, the storage properties may
deteriorate.
The resin fine-particles preferably have a volume average particle

diameter of 10 nm to 300 nm, more preferably 40 nm to 200 nm. If the
volume average particle diameter is less than 10 nm, the resin emulsion
has a higher viscosity. Therefore, it is sometimes difficult to obtain an
ink viscosity dischargeable in an inkjet printer. If the average particle
diameter is more than 300 nm, a nozzle of the printer may be clogged
with the particles, causing ejection malfunction.
Further, for the quantity of silicone originating from the silicone
modified acrylic resin in the recording ink, 100 ppm to 400 ppm is
preferable, and 100 ppm to 300 ppm is more preferable. If the quantity
of the silicone is less than 100 ppm, a coating with excellent abrasion
properties and marker resistance may not be obtained, and if it is more
than 400 ppm, the tendency of hydrophobicity becomes greater and thus
the stability in the aqueous ink may deteriorate.
For the minimum film forming temperature (MFT) of the silicone
modified acrylic resin not containing the hydrolyzable silyl group, 20°C
or less is preferable, and 0°C or less is more preferable. If the minimum
film forming temperature is more than 20°C, sufficient fixation may not
be obtained, and when the printed portion is rubbed or traced with a
marker pen, the pigment is removed and the recording medium may be
smeared.
In the present invention, it is preferable that a total amount of
the water-dispersible resin and the pigment as the coloring agent is 5%
by mass to 40% by mass in the ink, and a mass ratio A/B of the water-
dispersible resin A to the pigment B is 0.5 to 4, preferably 1 to 2.5.
Prints having high fixing ability and textures close to those of

commercial printing can be attained on the low-priced recording medium
for use in the present invention, by combining the ink and the recording
medium described in the present specification.
In the second embodiment of the ink of the present invention,
solids mass of the dipeptide in the ink is preferably 1 part by mass to 20
parts by mass, more preferably 3 parts by mass to 10 parts by mass.
Moreover, the ink further needs to satisfy the abovementioned amount
and ratio of the water-dispersible resin and the pigment as the coloring
agent relative to the total solids content of the ink, in order to satisfy the
objects of the present invention.
Specifically, the solids content of the water-dispersible resin and
the pigment as the coloring agent needs to be 5% by mass to 40% by
mass relative to the total solids contents of the ink. If the solids content
is less than 5% by mass, fixing ability and the like become insufficient
against the recording medium for use in the present invention. If the
solids content is more than 40% by mass, the viscosity of the ink is
excessively increased, and thus reliability such as for ejection of the ink
may be adversely affected. The solids content is more preferably 5% by
mass to 20% by mass. Moreover, resin dispersion, and a resin-coated
pigment can be used in the ink, depending on the selection of the coloring
agent. In this case, the resin dispersion and resin component of the
resin-coated particle are counted as a resin component of the ink,
together with the water-dispersible resin.
As mentioned above, the ratio A/B is 0.5 to 4. If the ratio is less
than 0.5, fixing ability and the like become insufficient against the

recording medium for use in the present invention. If the ratio is more
than 4, a density of the coloring agent is excessively low against the resin,
and thus it may lower the image quality, such as lowering the density,
uniformity of the image, and the like. Therefore, the important
structural requirements of the ink of the present invention are to add 1
part by mass to 20 parts by mass, preferably 3 parts by mass to 10 parts
by mass, of the dipeptide as the solid water retainer to the ink in solids
content, to satisfy the range of 5% by mass to 40% by mass of the total
amount of the water-dispersible resin and the pigment as the coloring
agent relative to the total solids of the ink, and to have a mass ratio A/B
of the water-dispersible resin A to the pigment as the coloring agent B.
-Water-soluble organic solvent-
Specific examples of the water-soluble organic solvent for use in
the present invention are as follow- polyvalent alcohols such as ethylene
glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene
glycol, tripropylene glycol, tetraethylene glycol, polyethylene glycol,
polypropylene glycol, 1,3-butanediol, 2 methyl-1,3-butanediol, 3-methyl-
1,3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-
hexanediol, glycerol/1,2,6-hexanetriol, l,2,4butanetriol, 1,2,3-
butanetriol, 2methyl-2,4-pentanediol, petriol, 3-methoxy-3-methyll-
butanediol, and the like; polyvalent alcohol alkyl ethers such as ethylene
glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene
glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene
glycol monobutyl ether, tetraethylene glycol monomethyl ether,
propylene glycol monoethyl ether, and the like; polyvalent alcohol aryl

ethers such as ethylene glycol monophenyl ether, ethylene glycol
monobenzyl ether, dipropylene glycol monobutyl ether, tripropylene
glycol monobutyl ether, diethylene glycol isobutyl ether, triethylene
glycol isobutyl ether, diethylene glycol isopropyl ether, and the like,'
nitrogen-containing heterocyclic compounds such as 2-pyrrolidone, N-
methyl-2-pyrrolidone, Nhydroxyethyl-2pyrrolidone, 1,3-
dimethylimidazohdinone, e-caprolactam, Y-butyrolactone, and the like;
amides such as formamide, N-methylformamide, formamide, N,N-
dimethylformamide, and the like; amines such as monoethanolamine,
diethanolamine, triethanolamine, monoethylamine, diethylamine,
triethylamine, and the like; sulfur-containing compounds such as
dimethylsulfoxide, sulfolane, thiodiethanol, thiodiglycol, and the like;
propylene carbonate, ethylene carbonate, and the like.
Among them, from the standpoint of obtaining excellent efficacy
in preventing ejection characteristic failure due to solubility and
moisture evaporation, glycerin, ethylene glycol, diethylene glycol,
triethylene glycol, propylene glycol, dipropylene glycol, tripropylene
glycol, 1,3-butanediol, 2methyll,3-butanediol, 3methyl-l,3-butanediol,
2,3-butanediol, 1,4-butanediol, 1,5-pentanediol, tetraethylene glycol, 1,6-
hexanediol, 2methyl-2,4-pentanediol, polyethylene glycol, 1,2,4-
butanetriol, 1,2,6-hexanetriol, thiodiglycol, 2-pyrrolidone, N-methyl-2-
pyrrolidone, Nhydroxyethyl-2-pyrrolidone, or l,3"dimethyl-2-
imidazolidinone is suitable.
The other components are not particularly limited and may be
appropriately selected according to the purpose. For example,

fungicides, rust prevention agents, pH adjusters, and the like may be
used. By using 1,2-benzisothiazolin-3-one as the fungicide, there can be
provided an ink having excellent performance of the fungicide, while
maintaining reliability such as storage stability, ejection stability, and
the like. Especially when the above-mentioned fungicide is used in
combination with the solid water retainer mentioned in the present
specification, the fungicide can exhibit sufficient effects at the addition
amount which is conventionally considered as an insufficient amount for
prevent generation of bacteria or fungi. By maintaining the addition
amount of the fungicide at the minimum, phenomena such as
aggregations of the particles or increased viscosity of the ink can be
prevented. Therefore, such ink is capable of exhibiting the excellent
performances as the ink for a long-period of time. The content of 1,2-
benzisothiazolin-3-one, as a content of an active ingredient, is preferably
0.01 parts by mass to 0.04 parts by mass with respect to the total amount
of the ink. If the content is less than 0.01, the effects of the fungicide
cannot be sufficiently exhibited. If the content is more than 0.04 parts
by mass, problems may occur in long-term storage stability, such as
causing aggregations of the pigment or increasing the viscosity of the ink
at 50% to 100% compared to the initial viscosity thereof after storing the
ink for a long period, e.g. for two years at a room temperature, or one to
three months at 50-60°C, and the performances at initial printing cannot
be maintained.
The pH adjusters are not particularly limited and any substances
may be used according to the purpose as long as they can be used to

adjust the pH for 7 or higher without adverse effects on the ink to be
prepared.
Examples of the pH adjusters include amines such as
diethanolamine and triethanolamine, alkali metal hydroxides such as
lithium hydroxide, sodium hydroxide, and potassium hydroxide;
ammonium hydroxide, quaternary ammonium hydroxide, quaternary
phosphonium hydroxide, alkali metal carbonates such as lithium
carbonate, sodium carbonate, potassium carbonate, and the like.
Examples of the rust prevention agents include acidic sulfite,
sodium thiosulfate, anmone thioglycolate, diisopropylammoniumnitrite,
pentaerythritol tetranitrate, dicyclohexylammoniumnitrite, and the like.
Water-soluble ultraviolet absorbers, water-soluble infra-red
absorber may be further added, depending on the purpose.
[Inkjet recording]
In the present invention, a total amount of the ink is precisely
restricted for the purpose of maintaining a drying property of the ink,
while preventing the pigment of the ink from penetrating into the
recording medium so as to make the pigment efficiently locate the area
adjacent to the surface of the recording medium. In the case of the
conventional inkjet printing where a large amount of the ink is used, the
functions of the barrier layer for separation the pigment coloring agent
from the ink cannot be sufficiently performed and thus the pigment
coloring agent is penetrated together with the solvent of the ink, or the
solvent of the ink is not dried at a sufficient speed and thus the drying
property is lowered. In order to sufficiently exhibit the functions of the

barrier layer, the maximum total amount of the ink is 15 g/m2 or less,
preferably 12 g/m2 or less. The amount of the ink can be easily
controlled. By reducing the total amount of the ink required for
printing, a size of an ink cartridge can be reduced compared to the size of
the ink cartridge in the conventional inkjet printer. Therefore, it is
possible to downsize an inkjet recording apparatus. In the case where
an ink cartridge in size of the conventional cartridge is used, the
frequency of exchanging the ink cartridge is reduced. Therefore,
printing can be conducted at low cost in this case. As a general
principle, the function of the barrier layer for separating the pigment
from the ink is more efficiently exhibited as the total amount of the ink is
smaller. However, if the total amount of the ink is excessively small,
there is a drawback such that image dots become small after printing.
Therefore, it is preferable to adjust the total amount of the ink within the
above-mentioned range depending images to be obtained.
In the present invention, the total amount of the ink is measured
in accordance with a weighting method. Specifically, a 5 cm X 20 cm
rectangular is printed on Type 6200 (manufactured by Ricoh Company
Limited) which is a plain paper for copiers (PPC). The mass of the
paper just after printing was measured, and a mass of the paper before
printing was deducted from the thus obtained value. 100 times of the
obtained value was defined as the total amount of the ink.
The ink having high permeability of the present invention can be
used for printing on the conventional porous recording media for inkjet
printing. However, in this case, the absorption speed of the ink is

excessively high compared to the case where printing is performed on the
recording medium for use in the present invention. Therefore, after
that a droplet of the ink is dropped on a surface of the paper, the solvent
of the ink is penetrated into the ink before the droplet is spread on the
surface, and thus a diameter of the dot becomes small. As a result,
lowered density or increased granular textures tends to be caused. In
order to obtain a high quality image on PPC, it is necessary to perform
printing by lowering resolution compared to the case when printing is
performed on the recording medium for used in the present invention.
However, if the resolution is lowered, the printing speed is slowed, or a
consumption of the ink is increased. Therefore, it is more preferably to
use the recording medium for use in the present invention, together with
the ink for inkjet printing of the present invention.
The ink of the ink media set of the present invention is suitably
used in printers provided with any types of inkjet heads including a
piezo_type in which a piezoelectric element is used to pressurize ink in
the ink passage, a diaphragm forming the wall of the ink passage is
deformed to change the inner volume of the ink passage, thereby
discharging ink droplets (Japanese Patent Application Laid-Open (JP-A)
No. 02-51734), a thermal type in which an exothermic resistor is used to
heat ink in the ink passage to produce bubbles (Japanese Patent
Application Laid-Open (JP-A) No. 61-59911), and an electrostatic type in
which a diaphragm forming the wall of the ink passage and electrodes
are placed at facing positions and electrostatic force is produced between
the diaphragm and the electrodes to deform the diaphragm and change

the inner volume of the ink passage, thereby discharging ink droplets
(Japanese Patent Application Laid-Open (JPA) No. 199471882).
As mentioned above, the recording medium of the ink media set
of the present invention is used together with the ink of the ink media
set of the present invention. This combination of the recording medium
and the ink is suitably used in various fields, and is suitably used in an
image recording apparatus, e.g. a printer, for inkjet recording. For
example, this combination of the recording medium and the ink is
suitably used for the ink cartridge, ink printed matter, inkjet recording
apparatus, and inkjet recording method of the present invention which
will be described below.
(Ink cartridge)
The ink cartridge of the present invention contains a container
containing the ink of the present invention therein, and further contains
other appropriated selected members as required.
The container is not particularly limited and its shape, structure,
size, and material are appropriately selected according to the purpose.
Preferred embodiments include those at least having an ink pouch
formed by aluminuni laminated film or resin film.
The ink cartridge is hereainafter described with reference to FIGs.
1 and 2. FIG.l is an illustration showing an embodiment of the ink
cartridge of the present invention. FIG.2 is an illustration of the ink
cartridge of FIG.l including a casing (exterior).
In an ink cartridge 200, as shown in FIG.l, an ink pouch 241 is
filled through an ink inlet 242. The ink inlet 242 is closed by fusion

bonding after the air is exhausted. An ink outlet 243 made of a rubber
material is pierced by a needle on the apparatus body for use, thereby
the ink is supplied to the apparatus. The ink pouch 241 is formed by a
packaging member such as a non-permeable aluminum laminated film.
The ink pouch 241 is housed in a cartridge case 244 generally made of
plastics as shown in FIG.2 and detachably mounted on various types of
inkjet recording apparatus.
The ink cartridge of the present invention contains the ink of the
ink media set of the present invention. The ink cartridge of the present
invention can be detachably mounted on variety types of inkjet recording
apparatus and it is particularly preferable that the ink cartridge of the
present invention is detachably mounted on the inkjet recording
apparatus of the present invention described below.
(Inkjet recording apparatus and inkjet recording method)
The inkjet recording apparatus of the present invention contains
the ink media set for inkjet recording of the present invention and an ink
ejecting unit, and may further contain appropriately selected other units,
such as a stimulus applying unit, a controlling unit, and the like.
The inkjet recording method of the present invention uses the ink
media set for inkjet recording of the present invention, and contains a
step of ejecting the ink. The inkjet recording method of the present
invention may further contain appropriately selected other steps, such as
a step of applying stimulus, a step of controlling, and the like, if
necessary.
The inkjet recording method of the present invention is suitable

performed by means of the inkjet recording apparatus of the present
invention, and the step of ejecting the ink is suitably performed by
means of the ink ejecting unit. Moreover, the above-mentioned other
steps are suitably performed by means of the above-mentioned other
units.
As mentioned above, the inkjet recording method contains a step
of ejecting the ink, which is to apply a stimulus to the ink for inkjet
recording, so as to eject the ink.
The step of ejecting the ink is to apply a stimulus to the ink of the
ink media set of the present invention, and to eject the ink to the
recording medium of the ink media set of the present invention, so as to
form an image.
The ink ejecting unit is configured to apply a stimulus to the ink
of the ink media set of the present invention, and to eject the ink so as to
form an image on the recording medium of the ink media set of the
present invention. The ink ejecting unit is not particularly limited, and
examples thereof include various nozzles for ejecting an ink, and the like.
It is preferable that the liquid chamber, fluid dragging part,
diaphragm, and nozzle member of the nozzle head part be at least partly
made of materials containing at least either silicon or nickel.
The nozzle diameter of the nozzle head part is preferably 30 µm
or less, more preferably 1 µm to 20 µm.
It is preferable that subtanks for supplying ink be provided on
the inkjet head and the ink is supplied to the subtanks from the ink
cartridge via supply tubes.

In the inkjet recording method of the present invention, the
maximum deposition amount of the ink is preferably 8 g/m2 to 20 g/m2 at
the resolution of 300 dpi or more.
The stimulus is generated, for example, by the stimulus applying
unit. The stimulus is appropriately selected depending on the purpose
without any restriction. Examples of the stimulus include heat,
pressure, vibration, light, and the like. One of them may be used alone,
or two or more of them may be used in combination. Among them, heat,
and pressure are particularly suitable.
Examples of the stimulus applying unit are a heating apparatus,
a pressurizing apparatus, a piezoelectric element, a vibration generation
apparatus, an ultrasonic oscillator, a light, and the like. Specific
examples thereof include a piezoelectric actuator such as a piezoelectric
element, a thermal actuator using an electrothermal conversion element
such as an exothermic resistor to cause film boiling and, accordingly,
phase change of a liquid, a shape-memory alloy actuator using metal
phase changes due to temperature changes, an electrostatic actuator
using electrostatic force, and the like.
An embodiment of the ejection of the ink of the ink media set is
appropriately selected depending on the stimulus to be applied, without
any restriction. For example, in the case where the stimulus is "heat,"
thermal energy corresponding to recording signals is applied to the ink in
the recording head, for example, using a thermal head, the thermal
energy causes the ink to bubble, and the bubble pressure urges the ink to
be ejected as ink droplets from the nozzle hole of the recording head. In

the case where the stimulus is "pressure," for example, an electric
voltage is applied to a piezoelectric element bonded at a position called a
pressure chamber within the ink passage of the recording head, the
piezoelectric element is bent, the pressure chamber is reduced in volume,
and thus the ink is ejected as droplets from the nozzle hole of the
recording head.
The droplet of the ink to be ejected preferably has a size of 1 pl to
40 pl, an ejection speed of the ink is preferably 5m/sec. to 20m/sec, a
driving frequency is preferably 1kHz or higher, and a resolution is
preferably 300dpi or higher.
The controlling unit is appropriately selected without any
restriction, provided that it is capable of controlling the motions of each
units described above. Examples of the controlling unit include devices
such as a sequencer, a computer, and the like.
An embodiment of the inkjet recording method of the present
invention by means of the inkjet recording apparatus of the present
invention is described hereinafter, with reference to the drawings; An
inkjet recording apparatus shown in FIG.3 contains an apparatus body
101, a feeder tray 102 attached to the apparatus body 101 for feeding
papers, a paper output tray 103 attached to the apparatus body 101 for
receiving papers on which images are recorded (formed), and an ink
cartridge mounting part 104. An operation part 105 having operation
keys and indicators is provided on the top surface of the ink cartridge
mounting part 104. The ink cartridge mounting part 104 has front
cover 115 that can be opened and/or closed to remove and/or place ink

cartridges 200.
As shown in FIGs. 4 and 5, a carriage 133 is supported slidably in
the scan direction by guide rod 131 that is a guide member laid across
not shown right and left side plates and stay 132 and moved by a main
motor (not shown) in the arrowed directions in FIG. 5 for scanning
within the apparatus body 101.
Recording heads 134 consisting of four inkjet recording heads
that eject yellow (Y), cyan (C), magenta (M), and black (B) recording ink
droplets, respectively, have ink ejection ports arranged in the
intersecting direction with the main scanning direction and they are
placed in the carriage 133 with their ink ejection direction downward.
Inkjet recording heads constituting the recording heads 134 are
provided with an energy generation unit for ejection the ink such as a
piezoelectric actuator such as an piezoelectric element, a thermal
actuator using an electrothermal conversion element such as an
exothermic resistor to cause film boiling and, accordingly, phase change
of a liquid, a shape-memory alloy actuator using metal phase changes
due to temperature changes, and an electrostatic actuator using
electrostatic force.
The carriage 133 is provided with subtanks 135 for supplying
each color ink to the recording heads 134. The subtanks 135 are filled
with the recording ink of the present invention from the ink cartridge
201 of the present invention mounted in the ink cartridge mounting part
105 via a not-shown recording ink supply tube.
A paper feed part for feeding paper 142 stuck on paper load part

(platen) 141 of the feed tray 102 comprises a half-moon roller ( feed roller
143) that separates and supplies the paper 142 from the paper load part
141 one by one and separation pad 144 that faces the feed roller 143 and
is made of a large friction coefficient material. . The separation pad 144
is biased toward the feed roller 143.
A conveying part for conveying the paper 142 supplied from the
feed part underneath the recording heads 134 comprises a conveying belt
151 for electrostatically adsorbing and conveying the paper 142, counter
roller 152 for conveying the paper 142 sent from the paper feed part via
guide 145 by clamping it together with the conveying belts 151,
conveying guide 153 for turning the paper 142 sent nearly vertically by
90° so as to lay it on the conveying belt 151, and leading end pressure
roller 155 that is biased toward the conveying belt 151 by presser
member 154. Charging roller 156 that is a charging unit for charging
the surface of the conveying belt 151 is also provided.
The conveying belt 151 is an endless belt, being placed over
conveying roller 157 and a tension roller 158 and running around in the
belt conveying direction. For example, the conveying belt 151 has a
front layer that is a paper adsorbing surface made of a dragging-
uncontrolled resin, for example a copolymer of tetrafluoroethylene and
ethylene (ETFE), having a thickness of 40µm and a back layer (an
intermediate dragging layer or an earth layer) made of the same
material as the front layer, but draggingcontrolled with carbon. Guide
member 161 is provided behind the conveying belt 151 at the
corresponding position to the printing area by the recording heads 134.

An output part for discharging the paper 142 on which recording was
done by the recording heads 134 comprises separation click 171 for
separating the paper 142 from the conveying belt 151, paper output
roller 172, and paper output roller 173. Paper output tray 103 is
disposed below paper output roller 172.
Double-side feeding unit 181 is detachably mounted in the back of
the apparatus body 101. The double-side feed unit 181 takes in the
paper 142 that is moved backward as the conveying belt 151 is rotated in
the reverse direction, turns it over, and feeds it again between the
counter roller 152 and the conveying belt 151. Manual feeder 182 is
provided on the top surface of the double-side feed unit 181.
In this inkjet recording apparatus, the paper 142 is separated
and fed from the paper feed part one by one. Being fed vertically, the
paper 142 is guided by the guide 145 and conveyed between the
conveying belt 151 and the counter roller 152. Then, it is guided by the
conveying guide 153 at the leading end and is pressed against the
conveying belt 151 by the leading end pressure roller 155 to change the
convey direction substantially by 90°.
Meanwhile, the conveying belt 151 is charged by the charging
roller 156, and the paper 142 is electrostatically adsorbed and conveyed
by the conveying belt 151. Then, the recording heads 134 are driven
according to image signals while the carriage 133 is moved. Ink
droplets are ejected on the paused paper 142 for recording one-line.
Then, the paper 142 is conveyed by a certain rate for recording the next
line. Receiving a recording end signal or a signal indicating the rear

end of the paper 142 has reached the recording area, the recording
operation is terminated and the paper 142 is ejected to the paper output
tray 103.
When it is detected that the remaining amount of the recording
ink in the subtank 135 is nearly to the end, a certain amount of recording
ink is supplied to the subtank 135 from the ink cartridge 200.
In this inkjet recording apparatus, when the recording ink in the
ink cartridge 200 of the present invention is used up, the case of the ink
cartridge 200 is disassembled and only the ink pouch contained therein
can be exchanged. The ink cartridge 200 allows for stable recording ink
supply even in a vertical and front mounting structure. Therefore,
when the apparatus body 101 is installed with the top being blocked by
something, for example, the ink cartridge 200 can be housed in a rack.
Even if something is placed on the top surface of the apparatus body 101,
the ink cartridge 200 can be easily replaced.
Here, the explanation is made with reference to an application in
a serial type (shuttle type) inkjet recording apparatus in which the
carriage scans is described. A line type inkjet recording apparatus
having a line head is also applicable.
The inkjet recording apparatus and inkjet recording method of
the present invention are applicable to various recording in an inkjet
recording system. For example, the inkjet recording apparatus and
inkjet recording method of the present invention can be particularly
preferably applied to inkjet recording printers, facsimiles, copy machines,
and printer/fax/copy complex machines.

An inkjet head to which the present invention is applied is
described hereinafter.
FIG. 6 is an enlarged view of the core part of the inkjet head
according to an embodiment of the present invention. FIG.7 is an
enlarged cross-sectional view of the core part of the same head in the
inter-channel direction.
This inkjet head comprises frame 10 having cutouts serving as an
ink supply port (not shown) and a common liquid chamber lb, passage
plate 20 having cutouts serving as fluid dragging part 2a and pressurized
liquid chamber 2b and communication port 2c that communicates to
nozzle 3a, diaphragm 60 having raised part 6a, diaphragm part 6b, and
ink inflow port 6c, laminated piezoelectric element 50 connected to the
diaphragm 60 via adhesive layer 70, and base 40 on which the laminated
piezoelectric element 50 is fixed. The base 40 is made of barium
titanate ceramics, on which two rows of laminated piezoelectric element
50 are arranged and connected.
The piezoelectric element 50 consists of alternately laminated
piezoelectric layers of lead zircohate titanate (PZT) having a thickness of
10 µm to 50 urn per layer and internal electrode layers of silver
palladium (AgPd) having a thickness of several µm per layer. The
internal electrode layers 52 are connected to external electrodes 53 at
both ends.
The laminated piezoelectric element 50 is divided into a comb-like
shape by half-cut dicing, having driving parts 56 and supporting parts
(non-driving part) 57 every other division (see FIG. 7).

The exterior of one of the two external electrodes 53 (connecting a
one end of the internal electrode layer in the surface or back side
direction in the figure) is processed, for example notched, for limiting on
length, thereby being divided by half-cut dicing. Multiple separate
electrodes 54 are formed. Not divided by dicing, the other is conductive
and serves as a common electrode 55.
A FPC (80) is soldered to the individual electrodes 54 of the
driving part. The common electrode 55 is turned in an electrode layer
provided at the end of the laminated piezoelectric layer and connected to
the Gnd electrode of the FPC (80). An un-shown driver IC is mounted
on the FPC (80) to control the application of driving voltage to the
driving part 56.
As for the diaphragm 60, thin film diaphragm part 62, island-
shaped raised part (island part) 61 formed at the center of the diaphragm
part 62 and connected to the laminated piezoelectric element 50 serving
as the driving parts 56, a thick part including beams to be connected to
the supporting part, and an opening serving as in ink inflow port 63 are
formed by electroforming two nickel plated films. The diaphragm has a
thickness of 3 µm arid a width (one side) of 35 µm.
The connections between the island part 61 of the diaphragm 60
and the movable parts 56 of the laminated piezoelectric element 50 and
between the diaphragm 60 and the frame 10 are made by patterning the
adhesive layer 70 including a gap material.
The passage plate 20 is made of a silicon mono-crystalline
substrate, in which cutouts serving as liquid dragging part 21 and

pressurized liquid chamber 22 and a through hole provided at the
corresponding position to the nozzle 31 and serving as communication
port 23 are patterned by etching.
The remaining part after the etching serves as a partition wall 24
of the pressurized liquid chamber 22. In this head, a part etched in a
smaller width serves as the liquid dragging part 21.
The nozzle plate 30 is made of a metal material such as a nickel
plated film formed by electroforming and has a number of nozzles 31
serving as fine ejection openings for discharging ink droplets. The
nozzle 31 has a horn-like (substantially cylindrical or substantially
truncated cone) internal shape (inner shape). The nozzle 31 has a
diameter of approximately 20 µm to 35 µm at the ink droplets ejection
side. The nozzle pitch in each row is 150dpi.
The ink discharging surface (nozzle front side) of the nozzle plate
30 is provided with a water-repellent finish layer having a not shown
water-repellent finish surface. A water-repellent finish film selected
according to ink's physical properties such as PTFE-Ni eutectoid plating
and electrodeposition of fluororesin, deposition of volatile fluororesin,
silicone resin and fluororesin solvent application and baking can be
provided to stabilize ink droplet shapes and ejection property and, thus,
ensure a high image quality. Among them, for example many
fluororesins are known; excellent waterrepellency can be obtained by
depositing modified perfluoropolyoxethane (by Daikin Industies, Ltd,
trade name: Optool DSX) to a thickness of 30 A to 100A.
The frame 10 in which cutouts serving as an ink supply inlet and

a common liquid chamber 12 are formed is made by molding a resin.
In an inkjet head having the above structure, a driving waveform
(10V to 50V pulse voltage) is applied to the driving part 56 according to
recording signals. The driving part 56 is shifted in the lamination
direction. The pressurized liquid chamber 22 is pressurized via the
diaphragm 30 and the pressure is increased, thereby ink droplets are
ejected from the nozzle 31.
After ejection of the ink droplets is completed, the ink pressure in
the pressurized liquid chamber 22 is decreased. The inertia ink flow
and driving pulse ejection process causes negative pressure within the
pressurized liquid chamber 22, leading to the ink supply step.
Meanwhile, the ink supplied from the ink tank enters the common liquid
chamber 12 and further fills the pressurized liquid chamber 22 from the
common liquid chamber 12 via the ink inflow port 63 and fluid dragging
part 21.
The fluid dragging part 21 effectively attenuates residual
pressure fluctuation while it stands against recharging (refilling) due to
surface tension. Appropriately selected dragging part balances residual
pressure attenuation with refilling time and shortens the transition time
to the next ink droplets ejection operation (driving cycle).
Examples
The present invention is illustrated in detail with reference to
examples given below, but these are not to be construed as limiting the
present invention.

(Preparation Example 1)
-Preparation of surface-treated carbon black pigment dispersion-
lb 3000 ml of 2.5 N defined sodium sulfate solution, there were
added 90 g of carbon black having a CTAB surface area of 150 m2/g, and
DBP oil absorption of 100 ml/100g, and the mixture was stirred at 300
rpm at 60°C for 10 hours so as to allow the mixture react and process a
oxidization treatment. The resulted reaction liquid was filtered, and the
obtained carbon black from the filtration was neutralized by using
sodium hydroxide, and then was subjected to ultrafiltration. Thus
obtained carbon black was washed with water, sequentially dried, and
then dispersed in pure water so as to be 20% by mass of the carbon black
in the dispersion.
(Preparation Example 2)
-Preparation of surface-treated yellow pigment dispersion-
C.I. Pigment Yellow 128 was subjected to a low temperature
plasma treatment so as to prepare the pigment wherein a carboxylic acid
group was introduced, as a yellow, pigment. The thus obtained pigment
was dispersed in ion-exchanged water, the dispersion was subjected to
desalination condensation by using an ultrafiltration membrane, to
thereby yield a yellow pigment dispersion having the pigment
condensation of 15%.
(Preparation Example 3)
-Preparation of surface-treated magenta pigment dispersion-
The surface-treated magenta pigment was prepared in the same
manner as in Preparation Example 2, provided that C.I. Pigment Yellow

128 was replaced with C.I. Pigment Red 122. Similarly to the case of
Preparation Example 2, the surface-treated pigment was easily dispersed
in an aqueous medium at the time of stirring, and the dispersion was
subjected to desalination condensation by using an ultrafiltration
membrane, to thereby yield a magenta pigment dispersion having the
pigment condensation of 15%.
(Preparation Example 4)
-Preparation of surface-treated cyan pigment dispersion-
The surface-treated cyan pigment was prepared in the same
manner as in Preparation Example 2, provided that C.I. Pigment Yellow
128 was replaced with C.I. Pigment Cyan 15-3. Similarly to the case of
Preparation Example 2, the surface-treated pigment was easily dispersed
in an aqueous medium at the time of stirring, and the dispersion was
subjected to desalination condensation by using an ultrafiltration
membrane, to thereby yield a cyan pigment dispersion having the
pigment condensation of 15%.
(Synthetic Example 1)
-Preparation of polymer dispersion-
After sufficiently replacing an inner atmosphere of a 1L flask
equipped with a mechanical stirrer, a thermometer, a nitrogen gas inlet
tube, a reflux tube and a dropping funnel with nitrogen gas, there were
loaded 11.2 g of styrene, 2.8 g of acrylic acid, 1.20 g of lauryl
methacrylate, 4.0 g of polyethylene glycolmethacrylate, 4.0 g of styrene
macromer (a product name: AS-6, a manufacturer: Toagosei Co., Ltd.),
and 0.4 g of mercaptoethanol, and the temperature was raised at 65 °C.

Separately, a mixture solution was prepared by mixing 100.8 g of styrene,
25.2 g of acrylic acid, 108.0 g of lauryl methacrylate, 36.0 g of
polyethylene glycolmethacrylate, 60.0 g of hydroxyethyl methacrylate,
36.0 g of styrene micromer (a product name: AS-6, a manufacturer-
Toagosei Co., Ltd.), 3.6 g of mercaptoethanol, 2.4 g of
azobisdimethylvaleronitril, and 18.0 g of methylethylketone, and the
mixture solution was dripped into the flask for 2.5 hours. After
completing the dripping, a mixture solution consisting of 0.8 g of
azobisdimethylvaleronitril and 18.0 g of methylethylketone was dripped
into the flask for 0.5 hours. The mixture in the flask was matured at
65°C for 1 hour. Thereafter, 0.8 g of asobisdimethylvaleronitril was
added thereto, and the mixture was further matured for 1 hour. After
completing the reaction, 364 g of methylethylketone was added in the
flask to thereby yield 800g of polymer solution having a condensation of
50%.
(Preparation Example 5)
-Preparation of dispersion of polymer particles containing a
phthalocyanine pigment-
After sufficiently mixing and stirring 28 g of the polymer solution
obtained in Synthesis Example 1, 26 g of a phthalocyanine pigment, 13.6
g of 1 mol/L potassium hydroxide solution, 20 g of methylethylketone,
and 30 g of ion-exchanged water, the mixture was kneaded by means of a
three-roll mill. The thus obtained paste was added to 200 g of ion-
exchanged water, and the mixture was sufficiently stirred. Thereafter,
the mixture was treated with an evaporator so as to evaporate

methylethylketone and water, to thereby obtained dispersion of polymer
particles in the color of cyan.
(Preparation Example 6)
-Preparation of dispersion of polymer particles containing a dimethyl
quinacridone pigment-
Dispersion of polymer particles in the color of magenta was
prepared in the same manner as in Preparation Example 5, provided
that the phthalocyanine pigment in Preparation Example 5 was replaced
with C.I. Pigment Red 122.
(Preparation Example 7)
-Preparation of dispersion of polymer particles containing a monoazo
yellow pigment-
Dispersion of polymer particles in the color of yellow was
prepared in the same manner as in Preparation Example 5, provided
that the phthalocyanine pigment in Preparation Example 5 was replaced
with C.I. Pigment Yellow 74.
(Preparation Example 8)
-Preparation of dispersion of polymer particles containing a carbon black
pigment-
Dispersion of polymer particles in the color of black was prepared
in the same manner as in Preparation Example 5, provided that the
phthalocyanine pigment in Preparation Example 5 was replaced with
carbon black.
(Preparation Example 9)
-Preparation of phthalocyanine pigment dispersion-

A mixture was obtained by mixing 150 g of C.I. Pigment Cyan
15:3, 110 g of a polyoxyethyleneßnaphtyleter pigment dispersant
expressed by the following general formula 1 (R1=l-20, L=10, n=40 in the
formula), 2 g of PIONIN A-51-B (a manufacturer: Takemoto Oil & Fat
Co., Ltd), and 738 g of distilled water. The thus obtained mixture was
dispersed, and thereafter was further dispersed by means of a disc-type
beads mill (a product type: KDL. a manufacturer: Shinmaru Enterprises
Corporation, a medium for use: zirconia balls having a diameter of 0.3
mm) while circulating through the beads mill for 20 hours, to thereby
obtained phthalocyanine pigment dispersion.

(Preparation Example 10)
-Preparation of dimethyl quinacridone pigment dispersion-
The dimethyl quinacridone pigment dispersion was prepared in
the same manner asin Preparation Example 9, provided that C.I.
Pigment Cyan 15:3 was replaced with C.I. Pigment Red 122.
-Preparation of monoazo yellow pigment dispersion-
The monoazo yellow pigment dispersion was prepared in the
same manner as in Preparation Example 9, provided that C.I. Pigment
Cyan 15:3 was replaced with C.I. Pigment Yellow 74.

Hereinafter, synthetic examples of acryl-silicones resin emulsion
as examples of the water-dispersible resin suitably used in the present
invention.
(Synthetic Example 2)
-Synthesis 1 of particles- made of acrylic resin modified with silicone
which does not include a reactive sylil group -
After sufficiently replacing an inner atmosphere of a 1L flask
equipped with a mechanical stirrer, a thermometer, a nitrogen gas inlet
tube, a reflux tube and a dropping funnel with nitrogen gas, there were
loaded 10 g of AQUARON RN-20 manufactured by Daiichi Kogyo
Seiyaku Co., Ltd., 10 g of potassium persulfite and 286 g of pure water,
and the temperature was raised at 65 °C. Separately, a mixture solution
was prepared by mixing 150 g of methyl methacrylate, 100 g of 2-
ethylhexyl acrylate, 20 g of acrylic acid, 20 g of vinyltriethoxy silane, 10 g
of AQUARON RN-20 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.,
4 g of potassium persulfite, and 398.3 g of pure water, and the mixture
solution was dripped into the flask for 2.5 hours. The mixture in the
flask was heated to mature at 80°C for 3 hour, and then cooled.
Thereafter, the pH value of the mixture was controlled to be ranging
from 7 to 8 by using potassium hydroxide. The thus obtained particles
were subjected to the measurement by means of MICROTTAC UPA
manufactured by Nikkiso Co., Ltd., and it was found out that the average
particle diameter thereof was 130 nm. In addition, a minimum
temperature for film formation was 0°C.
(Synthesis Example 3)

-Synthesis 2 of particles- made of acrylic resin modified with silicone
which does not include a reactive sylil group-
After sufficiently replacing an inner atmosphere of a 1L flask
equipped with a mechanical stirrer, a thermometer, a nitrogen gas inlet
tube, a reflux tube and a dropping funnel with nitrogen gas, there were
loaded 10 g of AQUARON RN-20 manufactured by Daiichi Kogyo
Seiyaku Co., Ltd., 10 g of potassium persulfite and 286 g of pure water,
and the temperature was raised at 65 °C. Separately, a mixture solution
was prepared by mixing 150 g of methyl methacrylate, 100 g of 2-
ethylhexyl acrylate, 20 g of acrylic acid, 40 g of hexyltrimethoxy silane,
10 g of AQUARON RN-20 manufactured by Daiichi Kogyo Seiyaku Co.,
Ltd., 4 g of potassium persulfite, and 398.3 g of pure water, and the
mixture solution was dripped into the flask for 3 hours. The mixture in
the flask was heated to mature at 80°C for 3 hour, and then cooled.
Thereafter, the pH value of the mixture was controlled to be ranging
from 7 to 8 by using potassium hydroxide. The thus obtained particles
were subjected to the measurement by means of MICROTTAC UPA
manufactured by Nikkiso Co., Ltd., and it was found out that the average
particle diameter thereof was 148 nm. In addition, a minimum
temperature for film formation was 0°C.
(Synthesis Example 4)
-Synthesis of particles- made of acrylic resin modified with silicone
containing a reactive sylil group-

The synthesis of a reactive sylil group containing silicone
modified acrylic resin particles was carried out in accordance with the
method described in Examples of JPA 1994-157861.
After sufficiently replacing an inner atmosphere of a 1L flask equipped
with a mechanical stirrer, a thermometer, a nitrogen gas inlet tube, a
reflux tube and a dropping funnel with nitrogen gas, there were loaded
100 g of pure water, 3 g of sodium dodecylbenzene sulfonate and 1 g of
polyethylene glycol nonylphenylether, further added with 1 g of
ammonium persulfite and 0.2 g of sodium hydrogen persulfite, and the
temperature was raised at 60°C. Separately, a mixture solution was
prepared by mixing 30 g of butyl acrylate, 40 g of methyl methacrylate,
19 g of butyl methacrylate, 10 g of potassium salt of vinylsilane triol, and
1 g of 3-methacryloxypropylmethyldimethoxysilane, and the mixture
solution was dripped into the flask for 3 hours. Thereafter, the pH
value of the mixture was controlled to be 7 by using ammonium solution.
The thus obtained particles were subjected to the measurement by
means of MICROTTAC UPA manufactured by Nikkiso Co., Ltd., and it
was found out that the average particle diameter thereof was 160 nm.
Ink solutions were prepared in accordance with the following
formulae, and were controlled their pH value to be 9 by using 10% by
mass lithium hydroxide aqueous solution. Thereafter, each solution was
filtered with a membrane having an average pore diameter of 0.8 um, to
thereby obtain each ink.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each m and n denotes 10.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.



In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denote 10.
(Comparative Production Example A-1)
-Comparative cyan pigment ink A-l-
A cyan ink was obtained in the same manner as in Production
Example A-5, provided that W-5025 was not added here.
(Comparative Production Example A-2)
-Comparative magenta pigment ink-
A magenta ink was obtained in the same manner as in Production
Example A-6, provided that W-5661 was not added here.

(Comparative Production Example A-3)
-Comparative yellow ink-
A yellow ink was obtained in the same manner as in Production
Example A-7, provided that the acryl-silicone resin emulsion of Synthesis
Example 3 was not added here.
(Comparative Production Example A-4)
-Comparative black pigment ink-
. A black ink was obtained in the same manner as in Production
Example A-8, provided that the acryl-silicone resin emulsion of Synthesis
Example 2 was not added here, and the compound expressed by the
formula above was replaced with a surfactant, F470 manufactured by
Dainippon Ink and Chemicals, Inc.
(Comparative Production Examples A-5 to A-8)
-Preparation of dye inks-
After mixing and sufficiently stirring the following substances so
as to dissolve, the mixture was subjected to the pressure filtration by
using a porous fluoro-filter manufactured by Sumitomo Electric
Industries, Ltd., to thereby prepare a dye ink set.
Compositions of dyelnks"



The composition of each ink in Production Examples and
Comparative Production Examples was shown in Table 1A.
In Table 1A, a surface tension, viscosity, a mass ratio A/B of the
coloring agent B to the water-dispersible resin A, of each ink are
presented.
Note that, the viscosity of each ink was measured by means of It-
type viscometer (a manufacturer: Toki Sangyo Co., Ltd.) at 25°C.


Flowingly, ink sets of Examples and Comparative Examples are
shown in Table 2A.


Ink solutions were prepared in accordance with the following
formulae, and were controlled their pH value to be 9 by using 10% by
mass lithium hydroxide aqueous solution. Thereafter, each solution was
filtered with a membrane having an average pore diameter of 0.8 µm, to
thereby obtain each ink.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.



In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.



In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1 and R3 denotes H, each of R2 and
R4 denotes CF3, each of p and r denotes 4, q denotes 1, m denotes 21, and
n is 0.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.


In the formula above, each of R1, R2, R3, and R4 denotes CF3, each
of p and r denotes 4, q denotes 1, and each of m and n denotes 10.
(Comparative Production Example B-1)
-Comparative cyan pigment ink B-1-
A cyan ink was obtained in the same manner as in Production
Example B-5, provided that dipeptide (alanyl glutamine) was not added
here.
(Comparative Production Example B-2)
-Comparative magenta pigment ink B-1-

A magenta ink was obtained in the same manner as in Production
Example B-6, provided that dipeptide (alanyl glutamine) was not added
here.
(Comparative Production Example B-3)
-Comparative yellow ink B-1-
A yellow ink was obtained in the same manner as in Production
Example B-7, provided that dipeptide (alanyl glutamine) was not added
here.
(Comparative Production Example B-4)
-Comparative black pigment ink B-1-
A black ink was obtained in the same manner as in Production
Example B-8, provided that dipeptide (alanyl glutamine) was not added
here.
(Comparative Production Examples B-5 to B-8)
-Preparation of dye inks-
After mixing and sufficiently stirring the following substances so
as to dissolve, the mixture was subjected to the pressure filtration by
using a porous fluoro-filter manufactured by Sumitomo Electric
Industries, Ltd., to thereby prepare a dye ink set.
Compositions of dye inks'-
(Type of dye)



(Comparative Production Example B-9)
An ink was obtained in the same manner as in Production
Example Bl, provided that dipeptide was replaced with 5% by mass of
urea.
(Comparative Production Example B-10)
An ink was obtained in the same manner as in Production
Example B-2, provided that dipeptide was replaced with 5% by mass of
urea.
(Comparative Production Example B-11)
An ink was obtained in the same manner as in Production
Example B-3, provided that dipeptide was replaced with 5% by mass of
urea.
(Comparative Production Example B-12)
An ink was obtained in the same manner as in Production
Example B-4, provided that dipeptide was replaced with 5% by mass of
urea.
The compositions of each ink in Production Examples and
Comparative Production Examples were shown in Table 1B.

In Table 1B, a surface tension of the ink, viscosity of the ink, a
solids mass of dipeptide (% by mass) in the ink are presented.
Note that, the viscosity of each ink was measured by means of It-
type viscometer (a manufacturer: Toki Sangyo Co., Ltd.) at 25°C.



A 0.3% slurry of the above formula was processed by means of a
fortlinear paper machine, and the thus obtained sheet was subjected to a
machine calendering treatment, to thereby yield Support 1 having basis
weight of 79 g/m2. Note that, at the time the slurry was processed to
make a sheet, a size-press treatment was performed, and an aqueous

solution of oxidized starch was applied onto each face of the sheet at 1.0
g/m2 in dry basis.
(Embodiment 1 of Recording Medium)
As a pigment, 70 parts by mass of kaolin (refractive index: 1.6, a
product name: Ultra White 90, a manufacturer: Engelhard Corporation)
having a particle size distribution such that 97% by mass of the particles
have a particle diameter of 2 µm or less, and 30part by mass of heavy
calcium carbonate (limestone powder) having an average particle
diameter of 1.1 µm, as a binder, 8 parts by mass of styrene butadiene
copolymer emulsion having a glass-transition temperature of -5°C, and 1
part by mass of phosphate starch, as an assistant, and 0.5 parts by mass
of calcium stearate were mixed, and water was added to this mixture to
thereby yield a coating liquid having solids content of 60% by mass.
The thus obtained coating liquid was applied on the both faces of
the support prepared in Production Example 1 of Base paper so as to
have a coating thickness of 1 µm per face. Thereafter, the coated
support was dried by hot air, and then was subjected to a super
calendaring treatment to thereby obtain Recording Medium 1.
(Embodiment 2 of Recording Medium)
Recording Medium 2 was prepared in the same manner as in
Embodiment 1 of Recording Medium, provided that a coating thickness
was changed to be 10 µm per face.
(Embodiment 3 of Recording Medium)
Recording Medium 3 was prepared in the same manner as in
Embodiment 1 of Recording Medium, provided that the inorganic

pigment contained in the coating liquid was changed to 100 parts by
mass (solids content) of TA100 (anatase type titanium oxide, a refractive
index: 2.5, a manufacturer: Fuji Titanium Industry Co., Ltd.).
(Embodiment 4 of Recording Medium)
Recording Medium 4 was prepared in the same manner as in
Embodiment 1 of Recording Medium, provided that the inorganic
pigment contained in the coating liquid was changed to 100 parts by
mass of TP-221 (precipitated calcium carbonate, a refractive index: 1.6
(1.59), a manufacturer: Okutama Kogyo Co., Ltd.).
(Embodiment 5 of Recording Medium)
A coated paper for gravure printing, Space DX, (containing kaolin
having a refractive index of 1.6 and calcium carbonate having a
refractive index of 1.6, a manufacturer: Nippon Paper Group, Inc.) was
used as Recording Medium 5.
(Embodiment 6 of Recording Medium)
A coated paper for electrophotography, POD Gloss, (containing
kaolin having a refractive index of 1.6 and calcium carbonate having a
refractive index of 1.6, a manufacturer: Oji Paper Co., Ltd.) was used as
Recording Medium 6.
(Embodiment 7 of Recording Medium)
A surface of the coated paper for electrophotography, POD Gloss,
(containing kaolin having a refractive index of 1.6 and calcium carbonate
having a refractive index of 1.6, a manufacturer: Oji Paper Co., Ltd.) was
polished with a wrapping paper twenty times so as to reduce a thickness

of the coating layer to be 5.1 µm. Recording Medium 7 was prepared in
this manner.
Next, the thus obtained Recording Media 17 were observed
under a scanning electron microscopy (FE-SEM S-4200, manufactured by
Hitachi, Ltd.), the observed images were translated into 2 digits. From
the observed images, it was confirmed that the diameter of pore was 1
µm or less, and that he area of the pores occupied in the surface of the
recording medium was 40% or less. Namely, all of Recording Media 1-7
satisfied the conditions required for the pores of the barrier layer.
(Examples A-l to A-6, and Comparative Examples A-l to A-2)
As shown in Table 3A, printing was performed at resolution of
600 dpi by using the ink and ink set shown in Table LA and Table 2A,
and a recording medium, by means of a prototype of a drop-on-demand
printer with a nozzle having a nozzle resolution of 384. The amount of
ink deposit was controlled by setting the maximum droplet size to be 18
pl, and the total amount of secondary color to be 140%. Solid images
and characters were printed in the following manner, provided that a
total amount of ink for 300 dots square did not exceed 15 g/m2 at the time
of printing the solid images. Quality and reliability of the thus obtained
images were evaluated in the following manner. The results are
presented in Table 3A.
(1) Image quality
1. Strike-through
Back sides of green solid images of Examples and Comparative
Examples were subjected to the measurements of image density, and the

density of strike through was determined by a value which took density
of background from the obtained value.
[Evaluation criteria]
A: 0.1 or less of strike-through density, and an image is uniformly
printed without causing any slight strike-through.
B- 0.15 or less of strike-through density, and an image is uniformly
printed without causing any slight strike-through.
C: 0.15 or less of strike-through density, but a slight strike-through is
observed.
D; Significant strike-through is observed.
Note that, the image of the evaluation criteria "D" does not
acceptable quality for inkjet printing image.
2. Beading
Green solid images of Examples and Comparative Examples were
observed with naked eyes for the existence and degree of beading, and
then evaluated based on the following criteria.
[Evaluation criteria]
5- an image is uniformly printed without any occurrence of beading.
4- Slight occurrence of beading is observed, but the degree of beading is
something which is not noticeable.
3: Occurrences of beading are observed, but the degree of beading is
something which does not adversely affect the quality of image.
2: Occurrences of beading are clearly observed.
1: Significant occurrences of beading are observed.
3. Evaluation of image density

Magenta solid images of Examples and Comparative Examples
were subjected to the measurement of optical density by means of X-Rite
932, and were evaluated by the following criteria.
[Evaluation criteria]
A: 1.6 or more of magenta image density.
B: 1.3 or more of magenta image density.
C: 1.0 or more of magenta image density.
D: Less than 1.0 of magenta image density.
Note that, the image of the evaluation criteria "D" does not
acceptable quality for inkjet printing image.
4. Evaluation of glossiness
Images of Examples and Comparative Examples were observed
with naked eyes for the degree of glossiness, and then were evaluated
based on the following criteria.
[Evaluation criteria]
A: High glossiness is observed
B: Glossiness is observed.
C: No glossiness is observed.
Note that, the image of the evaluation criteria "C" does not
acceptable quality for inkjet printing image.
(2) Image reliability

As samples for evaluation, a square image (3 cmx3 cm) was
prepared in each color of black, cyan, magenta, yellow, red, green, and
blue. After 24 hours from the printing, white cotton cloth (JIS L 0803,

Cotton No. 3) was attached to the sample with a double coated urethane
form tape 4016 (a manufacturer- Sumitomo 3M Limited, t=1.6), and the
sample was rubbed with the white cotton cloth for five times by means of
Clock Meter (CM-1 type). Thereafter, color density of the coloring agent
attached to the white cotton cloth was measured by means of
Spectrodensitometer (XRITE, Model-938).
[Evaluation criteria]
A: The color density of the coloring agent attached to the cotton cloth is
less than 0.05
B; The color density of the coloring agent attached to the cotton cloth is
0.05 or more, but less than 0.1.
C: The color density of the coloring agent attached to the cotton cloth is
0.1 or more.
Note that, the image of the evaluation criteria "C" does not
acceptable quality for inkjet printing image.


As shown in Table 3B, printing was performed at resolution of
600 dpi by using the ink and ink set shown in Table 1B and Table 2B,
and a recording medium, by means of a prototype of a drop-on-demand
printer with a nozzle having a nozzle resolution of 384. The amount of
ink deposit was controlled by setting the maximum droplet size to be 18
pi, and the total amount of secondary color to be 140%. Solid images
and characters were printed in the same manner as in Examples A-1 to
A-6, and Comparative Examples A-1 and A-2, so that a total amount of
ink for 300 dot square did not exceed 15 g/m2 at the time of printing the
solid images. Quality and reliability of the thus obtained images were
evaluated in the following manner. The results are presented in Table
3B.

(3) Reliability for clogging (Ejecting stability)
Evaluation of reliability for clogging at interval printing
Printing was performed on MY PAPER manufactured by NBS
Ricoh Co., Ltd., by means of a printer shown in FIG. 3. The printing

was performed by using each of a yellow ink, a magenta ink, a cyan ink
and a black ink at printing duty of 100%, and using a chart which had
5% of a printing area for each ink within a total area of the paper, as a
printing pattern. The printing conditions were of one-pass printing at a
recording concentration of 360 dpi.
By using the ink media sets of Examples B1 to B5 and
Comparative Examples B-l to B3, Evaluation 1 and Evaluation 2 were
sequentially performed.
The interval printing was performed in such manner that the
above-mentioned chart was continuously printed for 20 pieces, and then
the printer was rested without ejecting for 20 hours. This process was
repeated 50 times, and after 1000 prints in total, the chart was printed
once more, and then this print was evaluated with naked eyes on 5%
solid image part in the chart, whether or not lines, whiteout, or ejection
disturbance was present in the solid image.
[Evaluation criteria]
A: No lines, whiteout, or ejection disturbance is observed in the solid
image.
B: Lines, whiteout, or ejection disturbance is slightly observed in the
solid image.
C: Lines, whiteout, or ejection disturbance is slightly observed at first
scan.


Reliability for clogging when standing after continuous
printing
By using the ink medium sets of Examples B1 to B5 and
Comparative Examples B-1 to B3, reliability for clogging was evaluated.
The results are shown in Tables 5B, 6B, and 7B.
The evaluation was carried out under various environments,
namely environment 1 (23°C, 50%RH), environment 2 (10°C, 15%RH),
and environment 3 (27°C, 80%RH), by printing on MY PAPER
manufactured by NBS Ricoh Co., Ltd. by means of a printer shown in
FIG. 3. As a printing pattern, a standard test pattern J6 chart made by
Japanese Electron Industry Development Association (JEIDA) was used,
and the printing was continuously performed at recording density of 360
dpi at one-pass printing on 500 papers. Thereafter, it was stand for 20
hours, and then a printing was performed in the same manner to the
manner of before standing 20 hours. The resulted images were

evaluated with naked eyes whether or not lines, whiteout, or ejection
disturbance was present in the solid image.
[Evaluation criteria]
A: No lines, whiteout, or ejection disturbance is observed in the solid
image.
B: Lines, whiteout, or ejection disturbance is slightly observed in the
solid image.
C: Lines, whiteout, or ejection disturbance is slightly observed at first
scan.



Industrial Applicability
The ink for inkjet recording of the present invention provides
recording images of high optical density, provides highly uniform images
without causing beading or the like in a slid image, and has excellent
reliability for clogging and long-term storage stability, by using in
combination with a recording medium having a texture close to that of a
recording medium for commercial printings. Accordingly, the ink for

inkjet recording of the present invention can be suitable applied for an
ink set for inkjet recording, an ink medium set for inkjet recording, an
ink cartridge, an inkjet recording apparatus, and an inkjet recording
method.
The inkjet recording apparatus and inkjet recording method of
the present invention can be suitably adapted for various recording in
accordance with inkjet recording, for example, a inkjet recording printer,
a facsimile device, a photocopying machine, a complex machine
functioning a printer, facsimile, and photocopier, and the like.

We Claim:
1. An ink for inkjet recording, comprising:
water;
a water-soluble organic solvent, such as herein described;
a polyurethane resin emulsion;

a fluorochemical surfactant or derivative thereof, such as herein described; and
a coloring agent containing a pigment,
wherein the ink for inkjet recording has a surface tension of 20 mN/m to 35 mN/m at
25°C, and a viscosity of 5 mPa•s or more at 25°C,
a total amount of the polyurethane resin emulsion and the coloring agent in the ink for inkjet
recording is 5% by mass to 40% by mass, and a mass ratio A/B of the polyurethane resin
emulsion A to the coloring agent B is 0.5 to 4.
2. The ink for inkjet recording as claimed in claim 1, wherein the water-dispersible resin
is at least one selected from the group consisting of a anionic self-emulsified polyurethane ether
resin emulsion and an acryl-silicone resin emulsion.
3. The ink for inkjet recording as claimed in claim 1 or 2, wherein the surfactant is a
compound expressed by the following structural formula 1:

in the structural formula 1, each of R1 and R3 denotes either a hydrogen atom or a

group containing a fluorine atom, each of R2 and R4 denotes a group containing a fluorine atom,
and each of m, n, p, q and r denotes an integer.
4. The ink for inkjet recording as claimed in any one of claims 1 to 3, wherein the water-
soluble organic solvent is at least one selected from the group consisting of glycerin, trimethylol
propane, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene
glycol, tripropylene glycol, 2-methyl-l,3-propanediol, 1,3-butanediol, 2,3-butanediol, 1,4-
butanediol, 2-methyl-1,3-butanediol, 3-methyl-1,3-butanediol, .1,5-pentanediol, 1,6-hexanediol,
2-methyl-2,4-hexanediol, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone,
tetramethyl urea, and urea.
5. An ink set for inkjet recording, comprising:
a black ink; and
a color ink,
wherein each of the black ink and the color ink is the ink for inkjet recording as
claimed in any one of claims 1 to 4.
6. An ink media set for inkjet recording, comprising:
the ink for inkjet recording as claimed in any one of claims 1 to 4; and
a recording medium for inkjet recording,
wherein the ink contains the coloring agent containing a pigment, contains the water-
dispersible resin and the coloring agent at an amount of 5% by mass to 40% by mass in total, and
has a mass ratio A/B of the water-dispersible resin A to the coloring agent B is 0.5 to 4,
wherein the recording medium for inkjet recording contains a support containing a
cellulose pulp, and one or more barrier layer disposed on at least one face of the support, and

wherein the barrier layer comprises 30% by mass or more of an inorganic pigment
having a refractive index of 1.5 or more, excluding aluminum hydrate, and 10% by mass or less
of an inorganic pigment having an refractive index of less than 1.5.
7. The ink media set for inkjet recording as claimed in claim 6, wherein the barrier layer has a
thickness of 10 µm or less.
8. The ink media set for inkjet recording as claimed in any one of claim 6 or 7, wherein the
barrier layer has pores having a diameter of 1 µm or less, and a ratio of an area of the pores
occupying in the face of the recording medium for inkjet recording is 40% or less.
9. An ink cartridge, comprising:
a container; and
the ink for inkjet recording as claimed in any one of claims 1 to 6, contained in the
container.
10. An inkjet recording method, comprising:
applying a stimulus to an ink of the ink media set as claimed in any one of claims 6 to 8 and
ejecting the ink so as to record an image on a recording medium of the ink media set as claimed
in any one of claims 6 to 8.
11. The inkjet recording method as claimed in claim 10, wherein the stimulus is at least one
selected from the group consisting of heat, pressure, vibration, and light.

12. The inkjet recording method as claimed in claim 10 or 11, wherein the ink is ejected so
that the image is recorded at an ink deposited amount of 15 g/m2 or less.
13. An inkjet recording apparatus, comprising:
the ink media set for inkjet recording as claimed in any one of claims 6 to 8; and
an ink ejecting unit configured to apply a stimulus to the ink, and to eject the ink so as
to record an image on the recording medium.
14. The inkjet recording apparatus as claimed in claim 13, wherein the stimulus is at least
one selected from the group consisting of heat, pressure, vibration, and light.
15. The inkjet recording apparatus as claimed in claim 13 or 14, wherein the ink ejecting
unit ejects the ink on the recording medium so that an ink deposited amount on the recording
medium to be 15 g/m2 or less.
16. The inkjet recording apparatus as claimed in claims 13 to 15, optionally comprising a
member configured to turn over a side of the recording medium so as to enable a double-side
printing.


ABSTRACT

INK FOR INKJET RECORDING, INK SET FOR INKJET RECORDING, INK MEDIA
SET FOR INKJET RECORDING, INK CARTRIDGE, INKJET RECORDING METHOD,
AND INKJET RECORDING APPARATUS
The invention discloses an ink for inkjet recording, comprising: water; a water-soluble
organic solvent, such as herein described; a polyurethane resin emulsion; a fluorochemical
surfactant or derivative thereof, such as herein described; and a coloring agent containing a
pigment, wherein the ink for inkjet recording has a surface tension of 20 mN/m to 35 mN/m at
25°C, and a viscosity of 5 mPa•s or more at 25°C, a total amount of the polyurethane resin
emulsion and the coloring agent in the ink for inkjet recording is 5% by mass to 40% by mass,
and a mass ratio A/B of the polyurethane resin emulsion A to the coloring agent B is 0.5 to 4.
The invention also discloses an ink set for inkjet recording, an ink media set for inkjet
recording, an ink cartridge, an inkjet recording method and an inkjet recording apparatus as
described in the specification.

Documents:

02106-kolnp-2008-abstract.pdf

02106-kolnp-2008-claims.pdf

02106-kolnp-2008-correspondence others.pdf

02106-kolnp-2008-description complete.pdf

02106-kolnp-2008-drawings.pdf

02106-kolnp-2008-form 1.pdf

02106-kolnp-2008-form 3.pdf

02106-kolnp-2008-form 5.pdf

02106-kolnp-2008-gpa.pdf

02106-kolnp-2008-international publication.pdf

02106-kolnp-2008-international search report.pdf

02106-kolnp-2008-pct priority document notification.pdf

02106-kolnp-2008-pct request form.pdf

2106-KOLNP-2008-(15-05-2012)-EXAMINATION REPORT REPLY RECEIVED.pdf

2106-KOLNP-2008-(15-05-2012)-OTHERS.pdf

2106-KOLNP-2008-(29-05-2012)-ABSTRACT.pdf

2106-KOLNP-2008-(29-05-2012)-AMANDED CLAIMS.pdf

2106-KOLNP-2008-(29-05-2012)-AMANDED PAGES OF SPECIFICATION.pdf

2106-KOLNP-2008-(29-05-2012)-CORRESPONDENCE.pdf

2106-KOLNP-2008-(29-05-2012)-DESCRIPTION (COMPLETE).pdf

2106-KOLNP-2008-(29-05-2012)-DRAWINGS.pdf

2106-KOLNP-2008-(29-05-2012)-FORM-1.pdf

2106-KOLNP-2008-(29-05-2012)-FORM-2.pdf

2106-KOLNP-2008-(29-05-2012)-FORM-3.pdf

2106-KOLNP-2008-(29-05-2012)-OTHERS.pdf

2106-KOLNP-2008-(29-05-2012)-PETITION UNDER RULE 137.pdf

2106-KOLNP-2008-ASSIGNMENT.pdf

2106-KOLNP-2008-CORRESPONDENCE 1.1.pdf

2106-KOLNP-2008-CORRESPONDENCE 1.2.pdf

2106-KOLNP-2008-EXAMINATION REPORT.pdf

2106-KOLNP-2008-FORM 18 1.1.pdf

2106-kolnp-2008-form 18.pdf

2106-KOLNP-2008-FORM 3 1.1.pdf

2106-KOLNP-2008-FORM 3.1.pdf

2106-KOLNP-2008-FORM 5.pdf

2106-KOLNP-2008-GPA.pdf

2106-KOLNP-2008-GRANTED-ABSTRACT.pdf

2106-KOLNP-2008-GRANTED-CLAIMS.pdf

2106-KOLNP-2008-GRANTED-DESCRIPTION (COMPLETE).pdf

2106-KOLNP-2008-GRANTED-DRAWINGS.pdf

2106-KOLNP-2008-GRANTED-FORM 1.pdf

2106-KOLNP-2008-GRANTED-FORM 2.pdf

2106-KOLNP-2008-GRANTED-SPECIFICATION.pdf

2106-KOLNP-2008-INTERNATIONAL PUBLICATION.pdf

2106-KOLNP-2008-INTERNATIONAL SEARCH REPORT.pdf

2106-KOLNP-2008-OTHERS PCT FORM.pdf

2106-KOLNP-2008-OTHERS.pdf

2106-KOLNP-2008-PCT REQUEST FORM.pdf

2106-KOLNP-2008-REPLY TO EXAMINATION REPORT.pdf

abstract-2106-kolnp-2008.jpg


Patent Number 255482
Indian Patent Application Number 2106/KOLNP/2008
PG Journal Number 09/2013
Publication Date 01-Mar-2013
Grant Date 26-Feb-2013
Date of Filing 26-May-2008
Name of Patentee RICOH COMPANY, LTD.
Applicant Address 3-6, NAKAMAGOME 1-CHOME, OHTA-KU, TOKYO
Inventors:
# Inventor's Name Inventor's Address
1 NAMBA MICHIHIKO 770-63, YABE-CHO, TOTSUKA-KU, YOKOHAMA-SHI, KANAGAWA 244-0002
2 MOROHOSHI NAOYA 319-514, ASHITAKA, NUMAZU-SHI, SHIZUOKA 410-0001
3 OHSHIMA TOHRU LUPINUS 202, 1-7-29, HAYASHI, ATSUGI-SHI, KANAGAWA 243-0816
4 KOYANO MASAYUKI 6-34-4-608, SAGAMIGAOKA, ZAMA-SHI, KANAGAWA 228-0001
5 GOTOH AKIHIKO BON MAISON HONATSUGI 701, 3-14-8, NAKA-CHO, ATSUGI-SHI, KANAGAWA 243-0018
6 NAGAI KIYOFUMI FINE HILL VILLAGE 102, 2212-1, NARUSE, MACHIDA-SHI, TOKYO 194-0044
7 MATSUYAMA AKIHIKO GARDEN HEIGHTS SHIKOEN 102, 219-3, ISHIDA, ISEHARA-SHI, KANAGAWA 259-1116
PCT International Classification Number C09D 11/00,B41M 2/01
PCT International Application Number PCT/JP2007/067361
PCT International Filing date 2007-08-30
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2006-251771 2006-09-15 Japan
2 2006-251880 2006-09-15 Japan