Title of Invention

A WATER-BASED COMPOSITION

Abstract A water-based resin composition containing a copolymer (A) which is obtained by carrying out emulsion polymerization of an unsaturated monomer composed of 6 to 50 parts by mass of an ethylenically unsaturated monomer (a), represented by the following general formula (I), having a piperidyl group in a molecule and 50 to 94 parts by mass of an ethylenically unsaturated monomer (b), which does not substantially contain an ethylenically unsaturated monomer having a functional group represented by the following formula (II), (III), or (IV) in a molecule, with the total of the ethylenically unsaturated monomers (a) and (b) being 100 parts by mass, under the coexistence of 0.1 to 10 parts by mass of an emulsifier and 0.1 to 10 parts by mass of a chin transfer agent wherein R1 represents a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, X represents an oxygen atom or an imino group, Y represents a hydrogen atom or an alkyl or alkoxyl group having 1 to 20 carbon atoms, and z represents a hydrogen atom or a cyano group. -COOH ....(II) -SO3H ... (Ill) -PO3H ... (IV)
Full Text DESCRIPTION
WATER-BASED RESIN COMPOSITION, WEATHER RESISTANCE
IMPROVER FOR WATER-BASED PAINT USING THE SAME, WEATHER
RESISTANCE IMPROVER FOR THERMOPLASTIC RESIN, AND WEATHER
RESISTANCE IMPROVER FOR SOLVENT-BASED PAINT
TECHNICAL FIELD
[0001]
The present invention relates to a water-based resin composition.
Specifically, the present invention relates to a water-based paint, which is
excellent in weather resistance, using the water-based resin composition.
Further, the present invention relates to a weather resistance improver for a
water-based paint using the water-based resin composition, which can sharply
improve weather resistance when added to the water-based paint.
Furthermore, the present invention relates to a weather resistance improver for
a thermoplastic resin and a weather resistance improver for a solvent-based
paint, both of which use a resin composition recovered from the water-based
resin composition, and these improvers can sharply improve weather
resistance when added to the thermoplastic resin and the solvent-based paint,
respectively.
BACKGROUND ART
[0002]
In recent years, there is a strong demand in improving durability of
polymer materials which are used under severe circumstances such as
outdoors from the viewpoints of reducing maintenance cost and reducing
environmental load by saving resources.
Among them, in the field of a paint, it is intended to change from a
solvent-based paint which uses an organic solvent as a medium to a
water-based paint which uses water as a dispersing medium, and the use of
the water-based paint is rapidly expanding. Consequently, demands for the
performance of the water-based paint have become high degree, and
water-based paints having high-degree weather resistance have been
proposed.
For example, there is a description, in Patent Document 1, that a paint,
which is made by copolymerizing an ultraviolet light absorber (hereinafter,
expressed as a "reactive UVA") having an unsaturated double bond, in a
molecule, capable of radical polymerization, with a polymerizable monomer
having a highly hydrophobic cyclohexyl group, having excellent weather
resistance for a long time without showing the bleed out of the UVA component
from the coating film can be obtained.
In Patent Document 2, there is a description that a paint, which is
made by copolymerizing a hindered amine type light stabilizer (hereinafter,
expressed as a "reactive HALS") having an unsaturated double bond in a
molecule and a polymerizable monomer having a highly hydrophobic
cyclohexyl group, having excellent weather resistance for a long time without
showing the bleed out of the HALS component from the coating film can be
obtained. .
Further, in Patent Document 3, there is a description that a paint
composed of an emulsion obtained by copolymerizing a reactive HALS at the
last stage of a multistage emulsion polymerization in the presence of a silane
coupling agent having a cyclohexyl group is excellent in compatibility and film
formability, and excellent weather resistance for a long time can be obtained.
[0003]
Further, in the field of a water-based paint, investigations concerning a
weather resistance improver have been carried out to improve only weather
resistance of a water-based paint with relatively low weather resistance, which
has been conventionally used, without changing physical properties of the
water-based paint. However, as to the water-based paint, there has been a
problem, in stability of quality of the water-based paint, in which, for example,
the weather resistance improver comes to bleed with time on the upper layer
when the weather resistance improver is added because the main medium of
the water-based paint is water. Further, there has been a problem that the
water-based paint does not realize sufficient performance even in the case of
forming a film using the water-based paint right after it is stirred because it is
difficult to homogeneously disperse the weather resistance improver.
As countermeasures to these problems, in Patent Document 4, a
technology has been proposed, in which a nonreactive UVA or a nonreactive
HALS which does not have an unsaturated double bond in a molecule is
previously dispersed in water using an emulsifier and then the resultant
dispersion is added to the water-based paint to improve weather resistance of
the water-based paint.
Further, in the field of a thermoplastic resin to be used for automobiles
and building materials, a weather resistance improver such as HALS, UVA, or
an antioxidant in accordance with characteristics of each thermoplastic resin
has been proposed. However, in the case of the weather resistance improver
having relatively low molecular mass, it is difficult to maintain capability for
improving weather resistance for a long time owing to bleed out of the weather
resistance improver with time, which results in concentration lowering of the
weather resistance improver in a base material. To solve such a problem, a
polymer type weather resistance improver has been proposed. In Patent
Document 5, a technology of improving weather resistance of a thermoplastic
resin has been proposed, in which a reactive UVAand a reactive HALS are
copolymerized in high concentration in an organic solvent and the resultant
mixture is reprecipitated in a poor solvent to recover the polymer type weather
resistance improver which is then compounded into the thermoplastic resin.
Patent Document 1: Japanese Patent Application Laid-Open No. Hei
8-198,130
Patent Document 2: Japanese Patent No. 2,637,574
Patent Document 3: Japanese Patent Application Laid-Open No. 2004-10,805
Patent Document 4: Japanese Patent Publication No. Hei 3-46,506
Patent Document 5: Japanese Patent Application Laid-Open No. 2003-40,937
DISCLOSURE OF INVENTION
PROBLEM TO BE SOLVED BY THE INVENTION
[0004]
However, when these proposals were evaluated from the viewpoint of
a water-based paint having high-degree weather resistance, a water-based
paint with insufficient weather resistance, the value of which was about 4,000
hours in terms of the value obtained by an accelerated test of a sunshine
weatherometer, was merely obtained according to the method of Patent
Document 1. Further, according to the method of Patent Document 2, the
emulsifier to be used was restricted because the polymerization stability is
degraded owing to the occurrence of emulsion polymerization of an
unsaturated monomer containing an acidic functional group (hereinafter,
expressed as an "acid component") and the reactive HALS at the same
polymerization stage. Further, in this case, radical scavenging capability of a
HALS component was lowered by the acid component, because the acid
component was copolymerized, and hence weather resistance of the
water-based paint thus obtained was insufficient. According to the method of
Patent Document 3, the acid component was first copolymerized in the inside,
then neutralized, and then the reactive HALS was copolymerized at the final
stage so that polymerization stability was excellent, however, weather
resistance of the water-based paint thus obtained was insufficient for the same
reason as in the case of Patent Document 2 owing to the copolymerized acid
component.
Further, when these proposals were evaluated from the viewpoint of a
weather resistance improver for water-based paints, according to the method
of Patent Document 4, it was difficult to maintain weather resistance of a
coating film for a long time because bleed out of a weather resistance improver
with time from the coating film occurred owing to low molecular mass of the
weather resistance improver. Further, when an emulsion obtained by the
method of Patent Document 3 was used as a weather resistance improver,
capability for improving weather resistance of the weather resistance improver
was insufficient because diffusibility of the HALS component at the time of film
forming was low and radical scavenging capability of the HALS component
was lowered, owing to mutual interaction of the acid component and the HALS
component in an emulsion particle.
Further, when these proposals were evaluated from the viewpoint of a
weather resistance improver for thermoplastic resins, according to the method
of Patent Document 4, the weather resistance improver was produced by
extremely complicated method, in which the weather resistance improver was
recovered by reprecipitation after solution polymerization, which caused
problems in industrial production. Further, there remained a very small
amount of an organic solvent in the recovered material, which caused a
problem in the use where control of high-degree odor level was required.
[0005]
The present invention has been made in view of the above-mentioned
circumstances and a purpose of the present invention is to provide a
water-based resin which can be used not only as a water-based paint having
high-degree weather resistance but also, when added to another water-based
paint, as a weather resistance improver which can drastically improve the
weather resistance of the other water-based paint to which the weather
resistance improver has been added.
Further, another purpose of the present invention is to provide a
weather resistance improver which, when added to various thermoplastic
resins and solvent-based paints, can improve their weather resistance.
MEANS FOR SOLVING THE PROBLEM
[0006]
One aspect of the present invention resides in a water-based resin
composition containing a copolymer (A) which is obtained by carrying out
emulsion polymerization of an unsaturated monomer composed of 0.5 to 50
parts by mass of an ethylenically unsaturated monomer (a), represented by the
following general formula (I), having a piperidyl group in a molecule and 50 to
99.5 parts by mass of an ethylenically unsaturated monomer (b), which does
not substantially contain an ethylenically unsaturated monomer having a
functional group represented by the following formula (II), (III), or (IV) in a
molecule, with the total of the unethylenically unsaturated monomers (a) and
(b) being 100 parts by mass, under the coexistence of 0.1 to 10 parts by mass
of an emulsifier,
[Formula I]

wherein R1 represents a hydrogen atom or an alkyl group having 1 to 2 carbon
atoms, X represents an oxygen atom or an imino group, Y represents a
hydrogen atom or an alkyl or alkoxyl group having 1 to 20 carbon atoms, and Z
represents a hydrogen atom or a cyano group.
-COOH .....(II)
-SO3H .....(Ill)
-PO3H .....(IV)
[0007]
Another aspect of the present invention resides in a weather resistance
improver for water-based paints and a water-based paint both of which contain
the foregoing water-based resin composition.
Another aspect of the present invention resides in a resin composition
obtained by recovering solid matter in the foregoing water-based resin
composition.
Another aspect of the present invention resides in a weather resistance
improver for thermoplastic resins and a weather resistance improver for
solvent-based paints both of which include the foregoing resin composition.
BEST MODE FOR CARRYING OUT THE INVENTION
[0008]
The water-based resin composition of the present invention needs to
be the one in which the content of an ethylenically unsaturated monomer (a)
represented by the general formula (I) is 0.5 to 50 parts by mass, provided that
the total amount of the unsaturated monomers at the time of polymerization is
100 parts by mass. When the content of the ethylenically unsaturated
monomer (a) is 0.5 parts by mass or more, weather resistance of a coating film
obtained by using the water-based resin composition alone as a water-based
paint is largely improved. Further, the content of the ethylenically unsaturated
monomer (a) needs to be 50 parts by mass or less from the viewpoints of
polymerization stability and storage stability. Further, the content of the
ethylenically unsaturated monomer (a) is preferably 6 to 50 parts by mass in
the use in which high-degree pigment dispersibility or designability such as
matt is required as a coating film. When the content of the ethylenically
unsaturated monomer (a) is within this range, pigment dispersibility and
resin-beads dispersibility can be improved and hence excellent finish can be
obtained in the uses of clear paints and paints with various pigments.
Further, when the water-based resin composition of the present
invention is used as a weather resistance improver which is added to another
water-based paint to improve its weather resistance, the content of the
ethylenically unsaturated monomer (a) is preferably 6 to 50 parts by mass,
provided that the total amount of the unsaturated monomers at the time of
polymerization is 100 parts by mass, from the viewpoints of compatibility with a
polymer which constitutes the other water-based paint to which the weather
resistance improver for water-based paints is added and realization of weather
resistance of a coating film. When the content of the ethylenically
unsaturated monomer (a) is within this range, the weather resistance of the
water-based paint can be largely improved without any large changes in
physical properties of paint and physical properties of coating film of the
water-based paint obtained by adding a small amount of the weather
resistance improver for water-based paints. The content of the ethylenically
unsaturated monomer (a) is more preferably 20 to 50 parts by mass.
Further, when solid matter is recovered from the water-based resin
composition of the present invention and used also as a weather resistance
improver for thermoplastic resins, the content of the ethylenically unsaturated
monomer (a) is preferably 6 to 50 parts by mass, provided that the total amount
of the unsaturated monomers is 100 parts by mass. When the content of the
ethylenically unsaturated monomer (a) is within this range, the weather
resistance of a thermoplastic resin can be largely improved without any large
changes in physical properties and moldability of the thermoplastic resin by
adding a small amount of the weather resistance improver for thermoplastic
resins to the thermoplastic resin. The amount of use of the ethylenically
unsaturated monomer (a) is more preferably 20 to 50 parts by mass.
Further, when solid matter is recovered from the water-based resin
composition of the present invention and also used also as a weather
resistance improver for solvent-based paints, the content of the ethylenically
unsaturated monomer (a) is preferably 6 to 50 parts by mass, provided that the
total amount of the unsaturated monomers is 100 parts by mass. When the
content of the ethylenically unsaturated monomer (a) is within this range, the
weather resistance of a solvent-based paint can be largely improved without
any large changes in physical properties of the solvent-based paint and
physical properties of the coating film by adding a small amount of the weather
resistance improver for solvent-based paints to the solvent-based paint. The
amount of use of the ethylenically unsaturated monomer (a) is more preferably
20 to 50 parts by mass.
[0009]
As the ethylenically unsaturated monomer (a), the one having a
stabilizing function for ultraviolet light can be used, and for example,
4-(meth)acryloyloxy-2,2,6,6-tetramethylpiperidine,
4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine,
4-(meth)acryloyloxy-1,2,2,6,6-pentamethylpiperidine,
4-(meth)acryloylamino-1,2,2,6,6-pentamethylpiperidine, or
4-cyano-4-(meth)acryloyloxy-2,2,6,6-tetramethylpiperidine can be listed.
These monomers can be used alone or in combination of two or more
kinds when it is needed. When a methacrylate monomer in which R1 in the
general formula (I) is a methyl group is used alone or in combination of two or
more kinds as the ethylenically unsaturated monomer (a), a drastic improving
effect on weather resistance can be obtained in the case that the water-based
resin composition of the present invention is used as the weather resistance
improver for water-based paints, and, therefore, the methacrylate is preferable.
[0010]
An ethylenically unsaturated monomer (b) is the one which does not
substantially contain an ethylenically unsaturated monomer having an acidic
functional group represented by the formula (II), (III), or (IV) in a molecule
(hereinafter, expressed as an "acid monomer"). The expression "does not
substantially contain an ethylenically unsaturated monomer" means that the
content of the ethylenically unsaturated monomer is less than 0.1 %. When
the ethylenically unsaturated monomer (b) does not substantially contain the
acid monomer, stability of emulsion polymerization is largely improved.
Further, lowering of diffusibility and radical scavenging capability of a HALS
component caused by mutual interaction of the acidic functional group and the
HALS component in a coating film can be suppressed.
[0011]
As the ethylenically unsaturated monomer (b), for example, an alkyl
(meth)acrylate having an alkyl group with 1 to 12 carbon atoms such as methyl
(meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl
(meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, sec-butyl
(meth)acrylate, t-butyl acrylate, n-amyl (meth)acrylate, i-amyl (meth)acrylate,
n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate,
nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, lauryl
(meth)acrylate, or stearyl (meth)acrylate; a cycloalkyl (meth)acrylate such as
cycloalkyl (meth)acrylate or p-t-butylcyclohexyl (meth)acrylate; a radical
polymerizable monomer containing hydroxyl group such as 2-hydroxyethyl
(meth)acrylate, 2-(3-)hydroxypropyl (meth)acrylate, 4-hydroxybutyl
(meth)acrylate, or glycerol mono(meth)acrylate; a polymerizable monomer
containing a nitrogen atom such as (meth)acrylamide, N,N-dimethylaminoethyl
(meth)acrylate, vinylpyridine, or vinylimidazol; a halogen containing monomer
such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, or
tetrafluoroethylene; an aromatic monomer such as styrene, a-methylstyrene,
or vinyltoluene; a vinyl ester such as vinylacetate; a vinyl ether; or a
polymerizable cyano compound such as (meth)acrylonitrile can be used. The
foregoing ethylenically unsaturated monomer (b) can be used alone or in
combination of two or more kinds.
When the water-based resin composition of the present invention is
used as a water-based paint, a (meth)acrylate type unsaturated monomer is
preferably used from the viewpoint of weather resistance of the water-based
resin.
Further, when the water-based resin composition of the present
invention is used as a weather resistance improver for water-based paints, it is
most preferable to use main monomers, which give the water-based paints,
alone or in combination of two or more kinds, in accordance with the
water-based paints to which the weather resistance improver is added from the
viewpoint of maintaining various characteristics of the water-based paints.
Among them, it is preferable to use a (meth)acrylate type unsaturated
monomer from the viewpoint of improving weather resistance of the
water-based paints containing the weather resistance improver for
water-based paints of the present invention.
Further, when a resin composition obtained by recovering solid matter
from the water-based resin composition of the present invention is used as a
weather resistance improver for thermoplastic resins or a weather resistance
improver for solvent-based paints, it is preferable to use main monomers,
which constitute the thermoplastic resins or the solvent-based paints, alone or
in combination of two or more kinds, in accordance with the kinds of the
thermoplastic resins or the solvent-based paints to which the weather
resistance improver is added from the viewpoint of improving various
characteristics of the thermoplastic resins or the solvent-based paints.
[0012]
When the water-based resin composition of the present invention is
used as a water-based paint, a weather resistance improver for water-based
paints, a weather resistance improver for thermoplastic resins or a weather
resistance improver for solvent-based paints, deterioration of a resin and a
HALS component can be suppressed and weather resistance or capability for
improving weather resistance can be improved in any of the above uses, in the
case that an unsaturated monomer having an ultraviolet light absorbing group
represented by the following general formula (V), (VI), or (VII) in a molecule
(hereinafter, expressed as a " reactive UVA") is used as one component of the
ethylenically unsaturated monomer (b).
However, when a large amount of the reactive UVA is copolymerized,
there is a case that polymerization stability in an emulsion polymerization is
lowered or that transparency of a coating film is lowered. Consequently, when
the reactive UVA is used as one component of the ethylenically unsaturated
monomer (b), it is preferable that the reactive UVA be copolymerized in an
optimum range in accordance with the use of the water-based resin
composition of the present invention.
For example, when the water-based resin composition of the present
invention is used as the water-based paint, the amount of the reactive UVA is
preferably 2 parts by mass or less to 100 parts by mass of the total amount of
the unsaturated monomers at the time of polymerization. When the amount
of the reactive UVA is 2 parts by mass or less, yellowness of a coating film is
low and a coating film realizing high-degree weather resistance can be
obtained. Further, when the water-based resin composition of the present
invention is used as a weather resistance improver for water-based paints or a
weather resistance improver for solvent-based paints, the amount of the
reactive UVA is preferably within the range of from 5 to 20 parts by mass,
provided that the total amount of the unsaturated monomers at the time of
polymerization is 100 parts by mass. When the amount of the reactive UVA is
5 parts by mass or more, sufficient effects on absorbing ultraviolet light and on
improving weather resistance of the paint to which the water-based resin
composition has been added can be obtained with a small amount of addition
of the water-based resin composition, without changing various properties of
the paint. Further, when the amount of the reactive UVA is 20 parts by mass
or less, polymerization stability can be secured, and moreover, coloring of the
coating film of the paint to which the water-based resin composition has been
added can be evaded.
[0013]
In the case that the reactive UVA is copolymerized within the above
range and the resultant water-based resin composition of the present invention
is used as the weather resistance improver for water-based paints, mass
average molecular mass (Mw) of the copolymer (A) is particularly preferably
within the range of from 5,000 to 300,000. When the mass average molecular
mass (Mw) is 300,000 or less, diffusibility of the UVA component is improved
and coloring property of the coating film is further improved in the course of
forming films of the water-based paints to which the weather resistance
improver for water-based paints of the present invention is added. When the
mass average molecular mass (Mw) is 5,000 or more, bleed out of the UVA
component from the coating film can be suppressed and capability for
improving weather resistance for a long time can be given. The most
preferable mass average molecular mass of the copolymer (A) is from 5,000 to
200,000.
Further, in the case that a resin composition obtained by recovering
powder of the water-based resin composition of the present invention is used
as the weather resistance improver for thermoplastic resins, the amount of the
reactive UVA is preferably 20 parts by mass or less, provided that the total
amount of the unsaturated monomers at the time of polymerization is 100 parts
by mass. When the amount of the reactive UVA is 20 parts by mass or less,
sufficient polymerization stability can be obtained.
[0014]
[Formula V]

In the Formula (V), R2 represents a hydrogen atom or an alkyl group
having 1 to 2 carbon atoms, R3 represents a linear or a branched hydrocarbon
substituted group having 1 to 15 carbon atoms or a hydrocarbon substituted
group having a cyclic structure, and R4 represents a linear or a branched
hydrocarbon substituted group having 1 to 25 carbon atoms or a hydrocarbon
group having a cyclic structure.
[Formula VI]

In the Formula (VI), R5 represents a hydrogen atom or an alkyl group
having 1 to 2 carbon atoms, R6 represents a linear or a branched hydrocarbon
substituted group having 1 to 15 carbon atoms or a hydrocarbon substituted
group having a cyclic structure, and R7 represents a linear or a branched
hydrocarbon substituted group having 1 to 25 carbon atoms or a hydrocarbon
group having a cyclic structure.
[Formula VII]

In the Formula (VII), R8 represents a hydrogen atom or a methyl group,
and R9 to R12 independently represent a hydrogen atom or a linear alkyl group
having 1 to 10 carbon atoms, respectively.
[0015]
The water-based resin composition of the present invention has to be
subjected to emulsion polymerization in the presence of 0.1 to 10 parts by
mass of an emulsifier to 100 parts by mass of the total amount of the
unsaturated monomers at the time of polymerization. When the amount of
the emulsifier is 0.1 parts by mass or more, polymerization stability and
mechanical stability are improved. Further, when the amount of the emulsifier
is 10 parts by mass or less, water resistance of a coating film is not lowered in
the case that the water-based resin composition of the present invention is
used as a water-based paint or a weather resistance improver for water-based
paints. When 6 parts by mass or more of the reactive HALS is polymerized,
the amount of the emulsifier is preferably 1 part by mass or more in point of
polymerization stability. Further, in order to give further high-degree water
resistance to the coating film, the amount of the emulsifier to be used is
preferably 8 parts by mass or less.
[0016]
As the emulsifiers to be used, conventionally known various anion or
nonion emulsifiers, or polymer emulsifiers, or the like can be listed. Further,
when a reactive emulsifier having a radical polymerizable unsaturated double
bond in a molecule is used, higher-degree water resistance and weather
resistance can be given to the coating film in the case that the water-based
resin composition of the present invention is used as a water-based paint or a
weather resistance improver for water-based paints.
In the case that furthermore higher-degree water resistance and
weather resistance is desired to be given, it is preferable to use a reactive
anion emulsifier as the emulsifier. Further, in the case of the use in which, in
particular, high mechanical stability is needed, it is more preferable to jointly
use a reactive anion emulsifier and a reactive nonion emulsifier. Further, in
the case of the jointly using, the ratio of the reactive anion emulsifier to the
reactive nonion emulsifier is particularly preferably 8/2 to 2/8 (mass ratio).
The unsaturated monomer of the present invention does not contain the
reactive emulsifier.
[0017]
As the nonreactive emulsifier, an anion emulsifier such as "Newcol
560SF", "Newcol 562SF", "Newcol 707SF", "Newcol 707SN", "Newcol 714SF",
"Newcol 723SF", "Newcol 740SF", "Newcol 2308SF", "Newcol 2320SN",
"Newcol 1305SN", "Newcol 271A", "Newcol 271NH", "Newcol 210", "Newcol
220", "Newcol RA331", or "Newcol RA332" (each one is a trade name and
manufactured by Nippon Nyukazai Co., Ltd.), "Latemul B-118E", "Levenol WZ",
or "Neopelex G15" (each one is a trade name and manufactured by Kao
Corporation), or "Hightenol N08" (a trade name and manufactured by Dai-ichi
Kogyo Seiyaku Co., Ltd.), or an anion emulsifier such as "Nonipol 200" or
"Newpol PE-68" (each one is a trade name and manufactured by Sanyo
Chemical Industries, Ltd.) can be listed.
As the polymer emulsifier, for example, polyvinyl alcohol,
polyhydroxyethyl (meth)acrylate, polyhydroxypropyl (meth)acrylate, or
poly(vinylpyrrolidone) can be listed.
[0018]
As the reactive emulsifier, for example, a reactive anion emulsifier
such as "Antox MS-60" or "Antox MS-2N" (each one is a trade name and
manufactured by Nippon Nyukazai Co., Ltd.), "Eleminol JS-2" (a trade name
and manufactured by Sanyo Chemical Industries, Ltd.), "Latemul S-120",
"Latemul S-180", "Latemul S-180A", or "Latemul PD-104" (each one is a trade
name and manufactured by Kao Corporation), "Adeka Reasoap SR-10" or
"Adeka Reasoap SE-10" (each one is a trade name and manufactured by
Asahi Denka Kogyo K.K.), "Aquaron KH-05", "Aquaron KH-10", or"Aquaron
HS-10" (each one is a trade name and manufactured by Dai-ichi Kogyo
Seiyaku Co., Ltd.), or a reactive nonion emulsifier such as "Adeka Reasoap
NE-10", "Adeka Reasoap ER-10", "Adeka Reasoap NE-20", "Adeka Reasoap
ER-20", "Adeka Reasoap NE-30", "Adeka Reasoap ER-30", "Adeka Reasoap
NE-40", or "Adeka Reasoap ER-40" (each one is a trade name and
manufactured by Asahi Denka Kogyo K.K.), or "Aquaron RN-10", "Aquaron
RN-20", "Aquaron RN-30", or "Aquaron RN-50" (each one is a trade name and
manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) can be listed. They can be
used alone or in combination of two or more kinds when it is needed.
[0019]
When a monomer having a functional group with capability of radical
trapping in its side chain such as the ethylenically unsaturated monomer (a) is
subjected to emulsion polymerization, the resulting copolymer (A) forms a
crosslinked structure, in the case that the concentration of the ethylenically
unsaturated monomer (a) exceeds a certain amount. The water-based resin
composition of the present invention may have a crosslinked structure or a
noncrosslinked structure, however, it has preferably a noncrosslinked structure
or a low-crosslinked structure, and particularly preferably a noncrosslinked
structure. This is because, when the water-based resin composition of the
present invention alone is used as a water-based paint, for example, film
formability is improved and, as a result, water resistance and weather
resistance of the coating film are improved, though it depends on coating
conditions in the case that the copolymer (A) has the noncrosslinked structure
or the low-crosslinked structure.
In the case that the water-based resin composition of the present
invention is used as a weather resistance improver for water-based paints or in
the case that a resin composition recovered from the water-based resin
composition is used as a weather resistance improver for thermoplastic resins,
improving effect on weather resistance can be realized in a wider range of
water-based paints or thermoplastic resins because diffusibility of a HALS
component to the resin to which the HALS component is added is improved by
making the water-based resin composition or the resin composition have a
noncrosslinked structure or a low-crosslinked structure. Further, it is
preferable for a weather resistance improver for solvent-based paints to have a
noncrosslinked structure.
[0020]
As a measure for making the copolymer (A) to a polymer having a
low-crosslinked structure or a noncrosslinked structure, polymerization under
the coexistence of a chain transfer agent is also effective as well as a method
of increasing the amount of an initiator. Among them, in the case of the
water-based resin composition of the present invention, it is preferable to carry
out emulsion polymerization of the unsaturated monomers in the presence of
0.1 to 10 parts by mass of the chain transfer agent to 100 parts by mass of the
total amount of the unsaturated monomers at the time of polymerization.
When the amount of the chain transfer agent is 0.1 parts by mass or more,
crosslinking density can be lowered. When the amount of the chain transfer
agent exceeds 10 parts by mass, it is not preferable because a large amount of
the unreacted chain transfer agent remains in the polymer thus obtained and
Mw is drastically lowered. The more preferable range of the amount of the
chain transfer agent is 0.1 to 5 parts by mass in point of resistance to bleed out
and weather resistance.
As the chain transfer agent, a publicly known chain transfer agent like
a mercaptan-based chain transfer agent such as n-dodecyl mercaptan,
t-dodecyl mercaptan, n-octyl mercaptan, n-tetradecyl mercaptan, n-hexyl
mercaptan, or n-butyl mercaptan; a halogen compound such as
tetrachlorocarbon, or bromoethylene; a disulfide compound such as diphenyl
disulfide; or a-methylstyrene dimer can be used. These agents can be used
alone or in combination of two or more kinds.
[0021]
Further, mass average molecular mass (hereinafter, expressed as
"Mw") of the copolymer (A) constituting the water-based resin composition of
the present invention is not particularly limited, however, it is preferably within
the range of from 5,000 to 300,000 in accordance with the use of the
water-based resin composition of the present invention. For example, when
the present water-based resin composition is used as a weather resistance
improver for water-based paints, capability for improving weather resistance
can be realized in more kinds of water-based paints, provided that Mw of the
copolymer (A) is within this range. When the Mw of the copolymer (A) is
5,000 or more, bleed out of the copolymer (A) from the coating film obtained by
forming a water-based paint containing the weather resistance improver for
water-based paints of the present invention into a film can be suppressed and
a weather resistance over a long period of time can be held. When the Mw of
the copolymer (A) is 300,000 or less, diffusibility of the HALS component in a
film forming process is improved in the case that the weather resistance
improver for water-based paints of the present invention is added to
water-based paints in a wide range, and as a result, capability for improving
weather resistance of the weather resistance improver for water-based paints
and weather resistance of the coating film composed of the water-based paint
to which the weather resistance improver is added are improved.
[0022]
Further, when solid matter is recovered from the water-based resin
composition of the present invention and used as a weather resistance
improver for thermoplastic resins or a weather resistance improver for
solvent-based paints, the Mw of the copolymer (A) is preferably within the
range of from 5,000 to 300,000 because of the same reason as [that] in the
case of the weather resistance improver for water-based paints.
Further, when the water-based resin composition of the present
invention alone is used alone as a water-based paint, the Mw of the copolymer
(A) is preferably 20,000 or more, and more preferably within the range of from
20,000 to 300,000. When the Mw of the copolymer (A) is 20,000 or more,
weather resistance of the coating film can maintain sufficient weather
resistance. When the Mw of the copolymer (A) is 300,000 or less, film
formability is further improved and high water resistance and weather
resistance can be obtained. When the water-based resin composition of the
present invention is used as the water-based paint, the more preferable Mw of
the copolymer (A) is within the range of from 50,000 to 300,000.
[0023]
Further, when the water-based resin composition of the present
invention is used as the water-based paint and the weather resistance
improver for water-based paints, the minimum film forming temperature
(hereinafter, expressed as "MFT") measured by the method according to "JIS K
6828 5.11" is preferably 70°C or below. When the MFT is exceeding 70°C,
there is a case that film formability is inferior when the water-based resin
composition is used as the water-based paint, and sufficient water resistance
and weather resistance cannot be obtained with regard to the resultant coating
film. Further, when the water-based resin composition is used as the weather
resistance improver for water-based paints, it is apprehended that sufficient
diffusibility of the HALS component cannot be obtained in the course of a film
forming process of the water-based paint containing the weather resistance
improver for water-based paints of the present invention, and weather
resistance cannot be sufficiently improved with regard to the resultant coating
film. The most preferable MFT is 50°C or below.
[0024]
Further, the glass transition temperature (hereinafter, expressed as
"Tg") of the copolymer (A) which constitutes the water-based resin composition
of the present invention is not particularly limited, however, it is preferable to
change the Tg in accordance with the use of the water-based resin
composition. For example, in the case that the water-based resin
composition of the present invention is used as a water-based paint and a
weather resistance improver for water-based paints or a weather resistance
improver for solvent-based paints, the Tg of the copolymer (A) is preferably
100°C or below. When the Tg of the copolymer (A) is 100°C or below, the
water-based paint containing the water-based resin composition of the present
invention has good film formability and does not lower water resistance or
weather resistance of the resultant coating film. The Tg of the copolymer (A)
is preferably 70°C or below, and more preferably 50°C or below. Further, in
the case that the water-based resin composition of the present invention is
used as a weather resistance improver for thermoplastic resins, the Tg of the
copolymer (A) is preferably 50°C or above. When the Tg of the copolymer (A)
is 50°C or above, it becomes easy to maintain the primary particle structure of
solid matter at the time of recovering the solid matter, and good dispersibility of
the weather resistance improver for thermoplastic resins into the thermoplastic
resins can be secured. The Tg of the copolymer (A) is more preferably 70°C
or above. In the case that the water-based resin composition of the present
invention is used as a weather resistance improver for thermoplastic resins, it
is particularly preferable that a multistage polymerization be adopted at the
time of emulsion polymerization and a copolymer having a high Tg be formed
at the outermost layer in point of powder characteristics. As the foregoing Tg,
a calculated glass transition temperature obtained by the Fox equation is used.
The Fox equation is a relation equation of a glass transition temperature (°C) of
a copolymer and glass transition temperatures (°C) of homopolymers obtained
by independently homopolymerizing respective comonomers of the copolymer
as shown below.
1/(273 + Tg) = Z (Wi/(273 + Tgi))
(In the above equation, Wi represents a mass ratio of a monomer i and Tgi
represents a Tg (°C) of a homopolymer of the monomer i.)
As the Tg of each homopolymer, concretely, the values described in
"Polymer Handbook 3rd Edition" (Wiley-lnterscience Publication, 1989) can be
used.
[0025]
The water-based resin composition of the present invention can be
produced, for example, by emulsion polymerization with a radical
polymerization initiator using the ethylenically unsaturated monomer (a), the
ethylenically unsaturated monomer (b), and an emulsifier in a water medium.
The particle structure of the copolymer (A) constituting the water-based resin
composition of the present invention may be a monolayered structure or a
multilayered structure, however, in the case of the multilayered structure, a
three-layered structure or less is preferable from the viewpoints of production
efficiency and particle diameter control. Further, in the case of the
multilayered structure, it may be carried out, for example, to polymerize the
ethylenically unsaturated monomer (b) in the first step and then polymerize the
mixture of the ethylenically unsaturated monomer (a) and the ethylenically
unsaturated monomer (b) in the second step or later or to polymerize the
mixture of the ethylenically unsaturated monomers (a) and (b) in the first step
and then polymerize the ethylenically unsaturated monomer (b) in the second
step or later. It may be carried out to polymerize a mixture containing these
two monomers in the first step and then polymerize a mixture containing these
two monomers in a different ratio in the second step or later. In these cases,
the concentration of the ethylenically unsaturated monomer (a) in each step is
preferably 50 parts by mass or less, provided that the total amount of the
monomers in respective steps is 100 parts by mass. When the concentration
of the ethylenically unsaturated monomer (a) exceeds 50 parts by mass in
each step, polymerization stability of the step is lowered, and it is not
preferable.
[0026]
As the polymerization initiator for polymerizing the water-based resin
composition of the present invention, the one to be generally used in a radical
polymerization can be used, a concrete example of which includes a persulfate
such as potassium persulfate, sodium persulfate, or ammonium persulfate; an
oil-soluble azo compound such as azobisisobutyronitrile,
2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile),
2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), or
2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile; a water-soluble azo
compound such as
2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide},
2,2'-azobis{2-methyl-N-[2-(1-hydroxyethyl)]propionamide},
2,2'-azobis{2-methyl-N-[2-(1 -hydroxybutyl)]propionamide},
2,2'-azobis[2-(5-methyl-2-imidazolin-2-il)propane] or its salt,
2,2'-azobis[2-(2-imidazolin-2-il)propane] or its salt,
2,2'-azobis[2-(3,4,5,6-tetrahydropyrimidine-2-il)propane] or its salt,
2,2'-azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-il]propane} or its salt,
2,2'-azobis(2-methylpropionamidine) or its salt,
2,2'-azobis(2-methylpropinamidine) or its salt, or
2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] or its salt; or an
organic peroxide such as benzoyl peroxide, cumene hydroperoxide, t-butyl
hydroperoxide, t-butyl peroxy-2-ethylhexanoate, or t-butyl peroxyisobutylate
can be listed. These initiators can be used alone or in combination of two or
more kinds. Further, when promotion of polymerization speed or
polymerization at low temperature, namely 70°C or below, is desired, it is
advantageous to jointly use a reducing agent, for example, sodium bisulfite,
ferrous sulfate, or an ascorbate and a radical polymerization catalyst. The
amount of addition of the radical polymerization initiator is usually within the
range of from 0.01 to 10 parts by mass to the total amount of ethylenically
unsaturated monomers, and is particularly preferably 0.05 to 5 parts by mass in
consideration of progress of the polymerization or control of the reaction.
[0027]
Further, the particle diameter of the polymer particle constituting the
water-based resin composition of the present invention is not particularly
limited, however, it is preferable to select the optimum particle diameter in
accordance with the use of the water-based resin composition of the present
invention. As an average particle diameter, the one of cumulant analysis
obtained by the measurement at 25°C of the sample which was adjusted to 1%
concentration, using "Fiber-Optics Particle Analyzer with Autosampler
FPAR-1000" manufactured by Otsuka Electronics Co., Ltd. was adopted.
For example, in the case that the water-based resin composition of the
present invention alone is used as a water-based paint, the average particle
diameter is preferably in the range of from 30 to 200 nm. When the average
particle diameter is 30 nm or more, polymerization stability is improved and
hence the amount of an emulsifier to be used, which may be an important
factor of lowering of water resistance of the coating film, can be reduced.
When the average particle diameter is 200 nm or less, film formability of the
water-based paint is improved and hence various physical properties such as
water resistance and weather resistance of the coating film are improved.
Further, in the case that the water-based resin composition of the present
invention is used as a weather resistance improver for water-based paints, the
average particle diameter is preferably in the range of from 30 to 300 nm.
When the average particle diameter is 300 nm or less, diffusibility of the
weather resistance improver for water-based paints of the present invention
into the coating film is improved and hence high-degree improving
performance of weather resistance can be obtained owing to the HALS
component diffused in the coating film. As the average particle diameter, it is
more preferably 170 nm or less, and particularly preferably 140 nm or less.
Further, the average particle diameter is preferably 30 nm or more in order to
prevent lowering of water resistance of the coating film caused by an increase
in the emulsifier. Further, in the case that a resin composition obtained by
recovering solid matter in the water-based resin composition of the present
invention is used as a weather resistance improver for thermoplastic resins or
a weather resistance improver for solvent-based paints, the average particle
diameter is preferably 30 nm or more. When the average particle diameter is
30 nm or more, polymerization stability is improved.
[0028]
The solid matter concentration (hereinafter, expressed as "NV") of the
water-based resin composition of the present invention is not particularly
limited, however, it is preferably within the range of from 30 to 70 parts by mass.
In the case that the water-based resin composition of the present invention is
used as a water-based paint, sufficient film formability can be obtained and
hence appearance of the coating film is excellent, provided that the NV is 30
parts by mass or more. Further, in the case that the water-based resin
composition of the present invention is used as a weather resistance improver
for water-based paints, physical properties of paint of the water-based paint to
which the weather resistance improver for water-based paints has been added
can be maintained. Further, recovery efficiency of the solid matter in the
recovery step of the solid matter in the case of using the water-based resin
composition of the present invention as a weather resistance improver for
thermoplastic resins or a weather resistance improver for solvent-based paints
becomes sufficient. Further, when the NV is 70 parts by mass or less,
excellent polymerization stability can be obtained.
[0029]
As for the emulsion obtained by emulsion polymerization, stability of
the emulsion can be raised by adjusting the pH of the emulsion to become
weak aikalinic, namely within the range of from about 7.5 to 10.0, by adding a
basic compound after the polymerization. As the basic compound, for
example, ammonia, triethylamine, propylamine, dibutylamine, amylamine,
1-aminooctane, 2-(dimethylamino)ethanol, ethylaminoethanol,
2-(diethylamino)ethanol, 1-amino-2-propanol, 2-amino-1-propanol,
2-amino-2-methyl-1-propanol, 3-amino-1-propanol,
1-dimethylamino-2-propanol, 3-dimethylamino-1-propanol,
2-(propylamino)ethanol, ethoxypropylamine, aminobenzyl alcohol, morphorin,
sodium hydroxide, or potassium hydroxide can be listed. It is preferable to
use an inorganic basic compound in the case of the use such as an interior
which is desired not to contain VOC. Further, in the case where even a faint
odor is not desired, it is preferable to use a nonvolatile inorganic basic
compound such as sodium hydroxide or potassium hydroxide.
[0030]
In the case that the water-based resin composition of the present
invention is used as a water-based paint, one kind of the water-based paint
having the same composition alone or a mixture of two or more kinds of the
water-based paints having different compositions may be used. In order to
realize high-degree performances of the water-based paint of the present
invention, various pigments, a film-forming aid, a defoaming agent, a pigment
dispersing agent, a leveling agent, an anti-sagging agent, a matting agent, a
nonreactive HALS, a nonreactive ultraviolet light absorber, an antioxidant, a
heat resistance improver, a slip agent, a viscosity control agent, an antiseptic
agent, and the like may be added. Further, the water-based paint of the
present invention may be used after mixed with a melamine-based hardening+
agent, an epoxy-based hardening agent, or an isocyanate-based hardening
agent of emulsion type, water-soluble resin type, low molecular mass type, or
the like. In order to form coating films on surfaces of various materials using
the water-based paint containing the weather resistance improver for
water-based paints of the present invention, for example, a publicly known
coating method such as a spray coating method, a roller coating method, a bar
coating method, an air-knife coating method, a brush coating method, or a
dipping method may be properly selected and carried out.
The amount of addition of the weather resistance improver for
water-based paints in the case that the water-based resin composition of the
present invention is used as the weather resistance improver for water-based
paints is not particularly limited, however, it is preferably 1 to 50% by mass as
solid matter, provided that the sum of solid matter-of the weather resistance
improver for water-based paints and solid matter of the water-based paint to
which the weather resistance improver for water-based paints has been added
is 100% by mass. When the concentration of the weather resistance
improver for water-based paints of the present invention is less than 1% by
mass, there is a case that sufficient capability for improving weather resistance
of the coating film cannot be realized because the concentration of the
ethylenically unsaturated monomer (a) in the coating film becomes low even if
the concentration of the ethylenically unsaturated monomer (a) in the
copolymer (A) which constitutes the weather resistance improver for
water-based paints is sufficiently raised. Further, when the concentration of
the weather resistance improver for water-based paints of the present
invention is exceeding 50% by mass, the characteristics of the water-based
paint containing the weather resistance improver for water-based paints of the
present invention tends to be lowered. Further, as the weather resistance
improver for water-based paints of the present invention, one kind of a resin
having a same composition alone or a combination of two or more kinds of
resins having different compositions may be used.
The weather resistance improver for water-based paints of the present
invention can be used for various water-based paints such as an acrylic paint,
an acryl-silicone paint, a polyester paint, an urethane paint, a fluorine paint, a
vinyl chloride paint and an alkyd paint. Further, in order to realize high-degree
performances of the weather resistance improver for water-based paints of the
present invention and the water-based paint containing it, various pigments, a
film-forming aid, a defoaming agent, a pigment dispersing agent, a leveling
agent, an anti-sagging agent, a matting agent, a nonreactive HALS, a
nonreactive ultraviolet light absorber, an antioxidant, a heat resistance
improver, a slip agent, an antiseptic agent, and the like may be added. These
additives may be added to a mixture obtained after the weather resistance
improver for water-based paints of the present invention is added to the
water-based paint or to the water-based paint existing before the weather
resistance improver for water-based paints is added to the water-based paint.
Further, after these additives are added to the weather resistance improver for
water-based paints of the present invention, the resultant weather resistance
improver for water-based paints containing these additives may be added to
the water-based paint.
In order to form coating films on surfaces of various materials using the
water-based paint containing the weather resistance improver for water-based
paints of the present invention, a publicly known coating method such as a
spray coating method, a roller coating method, a bar coating method, an
air-knife coating method, a brush coating method, or a dipping method may be
properly selected and carried out.
[0031]
In the case that a resin composition obtained by recovering solid
matter in the water-based resin composition of the present invention is used as
a weather resistance improver for thermoplastic resins, one kind of a resin
having a same composition alone or a combination of two or more kinds of
resins having different compositions may be used. When the combination of
two or more kinds of resins is used, the solid matter may be recovered after the
two or more kinds of resins have been mixed or the respective resin
compositions obtained by separately recovering the solid matter may be mixed
to use.
As a method for recovering the solid matter, a publicly known method
such as a spray-drying method, a coagulation method or a centrifugation
method may be used, and it is preferable that the solid matter be recovered by
the spray-drying method or the coagulation method. As the method for
recovering the solid matter using the spray-drying method, a method in which a
water-based resin composition obtained by emulsion polymerization is
spray-dried and recovered as powder with a spray dryer under the conditions
of an inlet temperature of 120 to 220°C and an outlet temperature of 40 to 90°C
can be adopted. The outlet temperature is preferably 40 to 80°C in point of
disintegrability of a recovered secondary particle to a primary particle, and
particularly preferably 40 to 70°C.
Further, as the method for recovering the solid matter using the
coagulation method, a method in which a water-based resin composition is
contacted with a coagulating agent at 30 to 60°C, coagulated while stirred to
make a slurry, and the slurry is dehydrated and dried to recover powder can be
adopted. As the coagulating agent, for example, an inorganic acid such as
hydrochloric acid, sulfuric acid, nitric acid or phosphoric acid, an organic acid
such as formic acid or acetic acid, or an organic salt such as aluminum sulfate,
magnesium sulfate, calcium acetate or calcium sulfate can be listed.
The weather resistance improver for thermoplastic resins of the
present invention can be used for thermoplastic resins such as an acrylic resin,
a vinyl chloride resin, a polyethylene resin, a polypropylene resin, a
polystyrene resin, an ABS resin, a polyamide resin, a polyester resin and a
polycarbonate resin, and the amount of addition can be changed in accordance
with a target weather resistance. The weather resistance improver for
thermoplastic resins of the present invention can be molded together with the
thermoplastic resin to which it is added by a publicly known molding method
such as an injection molding method, an extrusion molding method, a blow
molding method, a press molding method, a calendering method, or an
inflation molding method.
The amount of addition of the weather resistance improver for
thermoplastic resins of the present invention is not particularly limited, however,
it is preferably 0.1 to 50% by mass to 100% by mass of the sum of the weather
resistance improver for thermoplastic resins and the thermoplastic resin.
When the amount of addition is less than 0.1% by mass, sufficient capability for
improving weather resistance tends to be lowered. Further, when the amount
of addition is exceeding 50% by mass, the characteristics of the thermoplastic
resin to which the weather resistance improver for thermoplastic resins is
added tends to be lowered. In order to realize high-degree performances of
the weather resistance improver for thermoplastic resins of the present
invention and the thermoplastic resin containing it, a mold release agent,
various kinds of pigments, a dye, a flame retardant, an ultraviolet light absorber,
an antioxidant, an antiseptic agent, an anti-fungus agent, and the like may be
added.
[0032]
In the case that a resin composition obtained by recovering solid
matter in the water-based resin composition of the present invention is used as
a weather resistance improver for solvent-based paints, the amount of addition
of the weather resistance improver for solvent-based paints is not particularly
limited, however, it is preferably within the range of from 1 to 50% by mass,
provided that 100% by mass of the sum of the solid matter of the weather
resistance improver for solvent-based paints and the solvent-based paint is
100% by mass. When the concentration of the weather resistance improver
for solvent-based paints of the present invention is 1% by mass or more,
weather resistance of the solvent-based paint to which the weather resistance
improver for solvent-based paints has been added is largely improved, and
when the concentration of the weather resistance improver for solvent-based
paints of the present invention is 50% by mass or less, its effect on the physical
properties of the solvent-based paint to which the weather resistance improver
for solvent-based paints has been added becomes limitative. Further, as the
weather resistance improver for solvent-based paints of the present invention,
one kind of a resin having a same composition alone or a combination of two or
more kinds of resins having different compositions may be used. The weather
resistance improver for solvent-based paints of the present invention can be
used for various solvent-based paints such as an acrylic paint, an acryl-silicone
paint, a polyester paint, a urethane paint, a fluorine paint, a vinyl chloride paint
and an alkyd paint.
The kind of the solvent-based paint may be a thermoplastic paint or a
thermosetting paint. Further, in order to realize high-degree performances of
the weather resistance improver for solvent-based paints of the present
invention and the solvent-based paint containing it, a brightening agent such as
aluminum paste or mica; a coloring agent such as titanium oxide, carbon black
or quinacridone; a pigment dispersing agent; a hardening agent such as
isocyanate, epoxy or melamine; a leveling agent; an anti-sagging agent; a
matting agent; a nonreactive HALS; a nonreactive ultraviolet light absorber; a
slip agent; or the like may be added. These additives may be added to a
mixture obtained after the weather resistance improver for solvent-based
paints of the present invention is added to the solvent-based paint or to the
solvent-based paint existing before the weather resistance improver for
solvent-based paints is added. Further, after these additives are added to the
weather resistance improver for solvent-based paints of the present invention,
the resultant weather resistance improver for solvent-based paints containing
these additives may be added to the solvent-based paint.
In order to form coating films on surfaces of various materials using the
solvent-based paint containing the weather resistance improver for
solvent-based paints of the present invention, a publicly known coating method
such as a spray coating method, a roller coating method, a bar coating method,
an air-knife coating method, a brush painting coating method, or a dipping
method may be properly selected and carried out to obtain a dried coating film
thickness of about 10 to 200 µm.
[0033]
In the case that the water-based resin composition of the present
invention is used as a water-based paint, solid matter content is not particularly
limited, however, it is usually used within the range of from 20 to 80% by mass.
Further, in this case, one kind of a water-based resin composition having a
same composition alone or a combination of two or more kinds of water-based
resin compositions having different compositions may be used. In order to
realize high-degree performances of the water-based paint of the present
invention, various pigments, a film-forming aid, a defoaming agent, a pigment
dispersing agent, a leveling agent, an anti-sagging agent, a matting agent, a
nonreactive HALS, a nonreactive ultraviolet light absorber, an antioxidant, a
heat resistance improver, a slip agent, a viscosity control agent, an antiseptic
agent, and the like may be added. Further, the water-based paint of the
present invention may be used after mixed with a melamine-based hardening
agent, an epoxy-based hardening agent, or an isocyanate-based hardening
agent of emulsion type, water-soluble resin type, low molecular mass type, or
the like. In order to form coating films on surfaces of various materials using
the water-based paint containing the weather resistance improver for
water-based paints of the present invention, for example, a publicly known
coating method such as a spray coating method, a roller coating method, a bar
coating method, an air-knife coating method, a brush coating method, or a
dipping method may be properly selected and carried out.
EXAMPLES
[0034]
Hereinafter, the present invention will be explained in more detail by
examples in accordance with the uses, however, the present invention is not
limited to these examples. In the following description, "part(s)" is expressed
in terms of mass basis.
Use as a water-based paint
Various evaluations of the water-based paint were carried out by the
following methods.
(Minimum film forming temperature (MFT))
MFT of a water-based resin composition was measured for 3 g of the
sample by a method according to "JIS K 6828 5.11" using a minimum film
forming temperature measuring device manufactured by Takabayashi Rika Co.
(Viscosity)
The value of viscosity of a water-based resin composition measured at
25°C using "R-100 viscometer" manufactured by Toki Sangyo Co., Ltd. was
adopted.
(Average particle diameter)
An average particle diameter of cumulant analysis of a resin
composition adjusted to 1% concentration, obtained by the measurement at
25°C using "Fiber-Optics Particle Analyzer with Autosampler FPAR-1000"
manufactured by Otsuka Electronics Co., Ltd. was adopted.
[0035]
(Mechanical stability test)
Using Maron mechanical stability tester, 100 g of a water-based resin
composition was tested for 10 minutes under the shear of 15 Kg, and the
tested sample was filtrated with a 100 mesh nylon screen, and the amount of
residue was measured and evaluated by the following standard.
"®": The amount of residue is less than 0.01 g or almost not seen.
"O": The amount of residue is 0.01 g or more and less than 0.1 g.
"?": The amount of residue is 0.1 g or more and less than 0.5 g.
"x": The amount of residue is 0.5 g or more , or gelation occurs during the test.
(Storage stability)
To a bottle of mayonnaise, 200 g of a water-based resin composition
was introduced, and the bottle thus packed was placed in a thermostatic water
bath kept at 50°C for one week. Subsequently, the water-based resin
composition was taken out and [coagulation] coagulated substance and
viscosity were confirmed and evaluated by the following standard.
"O": There is no coagulated substance and change rate of viscosity is less than
± 20%.
"O?" ; There is no coagulated substance and change rate of viscosity is ± 20%
or more and less than ± 30%.
"?": There is no coagulated substance and change rate of viscosity is ± 30% or
more,
"x": Coagulated substance is observed.
(Polymerization stability)
Cullet formed during polymerization was gathered by filtration using a
nylon screen and dried in a dryer at 50°C for 24 hours, and the dried material
was weighed and evaluated by the following standard.
"®": The amount of cullet in the dried state is less than 100 ppm.
"°": The amount of cullet in the dried state is 100 ppm or more and less than
300 ppm.
"O?": The amount of cullet in the dried state is 300 ppm or more and less than
1,000 ppm.
"?" : The amount of cullet in the dried state is 1,000 ppm or more, but
polymerization can be carried out.
"x" : Polymerization cannot be carried out because of instability of a system.
[0036]
(Mass average molecular mass (Mw))
To a sample bottle, 0.1 g of a water-based resin composition was
introduced, 10 g of tetrahydrofuran (THF) was added and the resultant mixture
was kept overnight at a room temperature. The sample solution thus
prepared was measured under the following conditions using "HCL-8120"
manufactured by Tosoh Corporation to obtain mass average molecular mass
(Mw). In the case that a peak was not detected after the retention time
exceeded 20 minutes, it was concluded that the sample solution had become
insoluble owing to formation of a crosslinked structure.
Column: TSK-gel; TSL-gel; Super HM-M x 4 pieces (6.0 mm ID. x 15 cmL)
Eluent: THF
Flow rate: 0.6 ml/min
Injection amount: 20 uJ
Column temperature: 40°C
Detector: differential refractive index detector (Rl)
[0037]
The test in the case of using the water-based resin composition of the
present invention as a water-based paint was carried out according to the
following method.

To 100 g of a water-based resin composition, "CS-12" (trade name,
manufactured by Chisso Corporation, film forming aid) was added to the extent
that the minimum film forming temperature of the water-based resin
composition became 5°C, and 0.5 g of "RHEOLATE350" (trade name,
manufactured by Rheox Inc., thickener) and 0.5 g of "Surfynol DF-58" (trade
name, manufactured by Air Products and Chemicals, Inc., defoaming agent)
were further added, and the mixture was sufficiently stirred and filtrated using a
100 mesh nylon screen to obtain a clear paint for weather resistance
evaluation.

"TIPAQUE CR-97" (trade name, manufactured by Ishihara Sangyo
Kaisha, Ltd., titanium oxide made by chloride process): 707 g, ____(trade
name, manufactured byAsahi Dennka Kogyo K.K., pigment dispersing agent):
12 g, Surfynol DF-58 (trade name, manufactured by Air Products and
Chemicals, Inc., defoaming agent): 25 g, and deionized water 256 g were
sufficiently mixed, and glass beads were added to the mixture and the pigment
was dispersed for 30 minutes using a high-speed disperser, and then the glass
beads and the like were filtrated with a 300 mesh nylon screen to obtain a mill
base for evaluation (solid content: 71% by mass).
Subsequently, to 100 g of a water-based resin composition (solid
content: 46% by mass), "CS-12" (trade name, manufactured by Chisso
Corporation, film forming aid) was added to the extent that the minimum film
forming temperature of the water-based resin composition became 5°C, and
42.7 g of the foregoing mill base and 0.5 g of "RHEOLATE350" (trade name,
manufactured by Rheox Inc., thickener) were added in this order, and the
resultant mixture was sufficiently stirred, and adjusted to have the viscosity of
about 30 seconds in terms of "Ford Cup #4" by adding deionized water.
Subsequently, the resultant mixture was filtrated again with a 300 mesh nylon
screen to obtain a white enamel paint for evaluation having 40% of PWC.

To 100 g of a water-based resin composition, "CS-12" (trade name,
manufactured by Chisso Corporation, film forming aid) was added to the extent
that the minimum film forming temperature of the water-based resin
composition became 5°C, and 10 g of "SP seal H" (trade name, manufactured
by Kaleido Co., silica matting agent), 0.5 g of "RHEOLATE350" (trade name,
manufactured by Rheox Inc., thickener) and 0.5 g of "Surfynol DF-58" (trade
name, manufactured by Air Products and Chemicals, Inc., defoaming agent)
were further added, and the mixture was sufficiently stirred and filtrated using a
100 mesh nylon screen to obtain a paint for silica-dispersibility evaluation.
This clear paint for evaluation was coated on a steel plate treated with zinc
phosphate treatment (steel plate treated with "Bondelite #100", thickness: 0.8
mm, 70 mm x 150 mm) by spray coating to the extent that the thickness of the
dried coating film became 30 |j.m, and kept at a room temperature for 1 hour
and subjected to forced drying at 80°C for 1 hour to obtain a coated plate for
silica-dispersibility evaluation. Using a value of gloss at 20 degrees of this
test plate as an index, the following standard was applied for evaluation.
The gloss at 20 degrees was measured using polarized light
glossmeter "VG-2000" (trade name) manufactured by Nippon Denshoku
Industries Co., Ltd.
"A": less than 5
"B": 5 or more and less than 10
"C": 10 or more
[0038]

A glass plate was coated with a clear paint using a 8 mil applicator, and
dried at a room temperature for 1 hour and subjected to forced drying at 80°C
for 1 hour to obtain a coated plate for evaluation of hot water resistance.
Subsequently, the coated plate was soaked in water at 50°C for 1 week.
Whitening, swelling and occurrence of blister right after the plate was taken out
were checked and judged according to the following standard.
"®": No change is observed.
"O": A little blue-whitening is observed, but swelling and peeling are not
observed.
"O?"; Whitening is observed, but swelling and peeling are not observed.
"?": Conspicuous whitening, or swelling and peeling is observed.
"x": Conspicuous whitening, swelling, and peeling are observed.

The clear paint for evaluation was coated on a steel plate treated with
zinc phosphate treatment (steel plate treated with "Bondelite #100", thickness:
0.8 mm, 70 mm x 150 mm) by spray coating to the extent that the thickness of
the dried coating film became 30 |am, and kept at a room temperature for 1
hour and subjected to forced drying at 80°C for 1 hour to obtain a coated plate
for evaluation of weather resistance for clearness. This coated plate was cut
to plates each having the size of 70 mm x 50 mm, and the resultant plates were
put in "Daipla Metal Weather KU-R4-W" (trade name, manufactured by Daipla
Wintes Co., Ltd.) and tested under the conditions of test cycle: 4 hours of
irradiation and 4 hours of moisture condensation; UV strength: 85 mW/cm2;
black panel temperature: 63°C at irradiation and 30°C at moisture
condensation; and humidity: 50%RH at irradiation and 96%RH at moisture
condensation, respectively. Using retentions of gloss at 60 degrees of the
test plates after elapse of 2,000 hours and 3,000 hours as indexes, the
following standard was applied for evaluation. The gloss at 60 degrees was
measured using polarized light glossmeter "VG-2000" (trade name)
manufactured by Nippon Denshoku Industries Co., Ltd.
"•": 85% or more
"O": 70% or more and less tan 85%
"O?": 55% or more and less than 70%
"?": 40% or more and less than 55%
"x": less than 40%
[0039]

The white enamel paint for evaluation was coated on a steel plate
treated with zinc phosphate treatment (steel plate treated with "Bondelite #100",
thickness: 0.8 mm, 70 mm x 150 mm) by spray coating to the extent that the
thickness of the dried coating film became 50 um, and kept at a room
temperature for 1 hour and subjected to forced drying at 80°C for 1 hour to
obtain a coated plate for evaluation of pigment dispersibility. Using a value of
gloss at 60 degrees of this test plate as an index, the following standard was
applied for evaluation.
The gloss at 60 degrees was measured using polarized light
glossmeter "VG-2000" (trade name) manufactured by Nippon Denshoku
Industries Co. Ltd.
"A": 75 or more
"B": 50 or more and less than 75
"C": less than 50

The white enamel paint for evaluation was coated on a steel plate
treated with zinc phosphate treatment (steel plate treated with "Bondelite #100",
thickness: 0.8 mm, 70 mm x 150 mm) by spray coating to the extent that the
thickness of the dried coating film became 50 µm, and kept at a room
temperature for 1 hour and subjected to forced drying at 80°C for 1 hour to
obtain a coated plate for evaluation of weather resistance for enamel coating.
This coated plate was cut to a plate having the size of 70 mm x 50 mm, and the
resultant plate was put in "Daipla Metal Weather KU-R4-W" (trade name,
manufactured by Daipla Wintes Co., Ltd.) and tested under the conditions of
test cycle: 4 hours of irradiation and 4 hours of moisture condensation; UV
strength: 85 mW/cm2; black panel temperature: 63°C at irradiation and 30°C at
moisture condensation; and humidity: 50%RH at irradiation and 96%RH at
moisture condensation. Using retention of gloss at 60 degrees of the test
plate after elapse of 2,000 hours as an index, the following standard was
applied for evaluation. The gloss at 60 degrees was measured using
polarized light glossmeter "VG-2000" (trade name) manufactured by Nippon
Denshoku Industries Co., Ltd.
"•": 90% or more
"°": 75% or more and less tan 90%
"O?": 60% or more and less than 75%
"?": 40% or more and less than 60%
"x": less than 40%
[0040]
Example 1
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 45 parts of
deionized water, 5% by mass of emulsion A compounded with the rate shown
in Table 1 and 0.2 part of 28% by mass aqueous ammonia were introduced,
and the resultant mixture was heated to 75°C while inside of the reactor was
replaced by nitrogen, and an initiator solution obtained by dissolving 0.1 part of
ammonium persulfate (polymerization initiator) into 5 parts of water was added
to form a seed particle. The temperature of the resultant solution was
measured by a thermometer, and after an exothermic peak was observed, the
remainder of the emulsion A was dropped by taking 4 hours at the inside
temperature of 75°C, and the resultant system was aged for 2 hours at the
same inside temperature of 75°C to polymerize a monomer of the emulsion A
and to form a copolymer (A).
Subsequently, the system was cooled, and 0.2 part of 28% by mass
aqueous ammonia was added at a temperature of 60°C or below to prepare a
water-based resin composition. The results of evaluation of the water-based
resin composition thus obtained are shown in Table 1.
Examples 2 to 10, Comparative Examples 1, 3, 4, 6 and 7
The same procedure as in Example 1 was carried out to prepare
water-based coating materials using the emulsion A compounded with the rate
shown in Tables 1 and 2. The results of evaluation are shown in Tables 1 and
2.
Comparative Examples 2 and 5
The same procedure as in Example 1 was carried out to start emulsion
polymerization using the emulsion A compounded with the rate shown in Table
2, however, coagulated materials were generated at the stage when a seed
particle was formed by adding the initiator solution obtained by dissolving 0.1
part of ammonium persulfate (polymerization initiator) into 5 parts of water, and
stirring became difficult owing to coagulated materials generated in course of
dropping of the remainder of the emulsion A, and hence the polymerization
was stopped.

HALS1:4-methacryloyloxy-2,2,6,6-tetramethylpiperidine
HALS2: 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine
"Adeka Reasoap SR-10": reactive anion type surfactant (trade name,
manufactured byAsahi Denka Kogyo K.K.)
"Adeka Reasoap ER-30": reactive nonion type surfactant (trade name,
manufactured byAsahi Denka Kogyo K.K.)
NDM: Normal dodecyl mercaptan
[0044]
It is obvious from Tables 1 and 2 that the water-based paints of the
present examples are excellent in weather resistance, silica dispersibility, hot
water resistance, and pigment dispersibility as well as mechanical stability,
storage stability and polymerization stability.
Contrary to this, the water-based paints of the comparative examples
are inferior in polymerization stability or storage stability, and at least one
characteristics of weather resistance, silica dispersibility, hot water resistance,
and pigment dispersibility are insufficient, even if they are polymerizable.
Consequently, it is obvious that the water-based paint having excellent
polymerization stability, mechanical stability, and storage stability, and
satisfying all the characteristics of weather resistance, silica dispersibility, hot
water resistance and pigment dispersibility can be provided according to the
present invention.
[0045]
Use as a weather resistance improver for water-based paints
Various evaluations of the weather resistance improver for
water-based paints were carried out according to the following methods.
Preparation of a clear paint>
A water-based resin composition is compounded to a water-based
paint of Reference Example 1 to be mentioned later with a fixed rate (shown in
a table). To 100 g of the prepared water-based paint, "CS-12" (trade name,
manufactured by Chisso Corporation, film forming aid) was added, as a film
forming aid, to the extent that the minimum film forming temperature of the
water-based paint became 5°C, and 0.5 g of "RHEOLATE350" (trade name,
manufactured by Rheox Inc., thickener) and 0.5 g of "Surfynol DF-58" (trade
name, manufactured by Air Products and Chemicals, Inc., defoaming agent)
were further added, and the mixture was sufficiently stirred and filtrated using
100 mesh nylon screen to obtain a clear paint for evaluation. The resultant
clear paint was coated on a steel plate treated with zinc phosphate treatment
(steel plate treated with "Bondelite #100", thickness: 0.8 mm, 70 mm x 150
mm) by spray coating to the extent that the thickness of the dried coating film
became 50 urn, and kept at a room temperature for 1 hour and subjected to
forced drying at 80°C for 1 hour to obtain a coated plate for the tests of weather
resistance and capability for improving weather resistance.

"TIPAQUE CR-97" (trade name, manufactured by Ishihara Sangyo
Kaisha, Ltd., titanium oxide made by chloride process): 707 g, "ADEKA COL
W-193" (trade name, manufactured byAsahi Denka Kogyo K.K., pigment
dispersing agent): 12 g, "Surfynol DF-58" (trade name, manufactured by Air
Products and Chemicals, Inc., defoaming agent): 25 g, and deionized water
256 g were sufficiently mixed, and glass beads were added to the resultant
mixture and dispersion of the pigment was carried out for 30 minutes using a
high-speed disperser, and then the glass beads and the like were filtrated with
300 mesh nylon screen to obtain a mill base for evaluation (solid content: 71%
by mass).
Subsequently, to 100 g of a water-based paint (solid content: 50% by
mass) obtained by compounding a water-based resin composition to a
water-based paint of Reference Example 1 to be mentioned later with a fixed
rate (shown in a table), "CS-12" (trade name, manufactured by Chisso
Corporation, film forming aid) was added, as a film forming aid, to the extent
that the minimum film forming temperature of the water-based paint became
5°C, and 47 g of the foregoing mill base for evaluation and 0.5 g of
"RHEOLATE350" (trade name, manufactured by Rheox Inc., thickener) were
added in this order, and the resultant mixture was sufficiently stirred, and
adjusted to have the viscosity of about 30 seconds in terms of "Ford Cup #4" by
adding deionized water. Subsequently, the resultant mixture was filtrated
again with a 300 mesh nylon screen to obtain a white enamel paint for
evaluation having 40% of PWC. The resultant white enamel paint was coated
on a steel plate treated with zinc phosphate treatment (steel plate treated with
"Bondelite #100", thickness: 0.8 mm, 70 mm x 150 mm) by spray coating to the
extent that the thickness of the dried coating film became 50 urn, and kept at a
room temperature for 1 hour and subjected to forced drying at 80°C for 1 hour
to obtain a coated plate for the tests of weather resistance, chalking, capability
for improving weather resistance and pigment dispersibility.
[0046]

The resultant coated plate for the test was put in a evaluation device
"Daipla Metal Weather KU-R4-W" (manufactured by Daipla Wintes Co., Ltd.)
and tested under the conditions of test cycle: 4 hours of irradiation and 4 hours
of moisture condensation; UV strength: 85 mW/cm2; black panel temperature:
63°C at irradiation and 30°C at moisture condensation; and humidity: 50%RH
at irradiation and 96%RH at moisture condensation. Using retention of gloss
at 60 degrees of the test plate after elapse of 2,000 hours as an index, the
following standard was applied for evaluation. The gloss at 60 degrees was
measured using polarized light glossmeter "VG-2000" manufactured by Nippon
Denshoku Industries Co., Ltd.
"®": 80% or more
"O": 70% or more and less tan 80%
"O?": 60% or more and less than 70%
"?": 50% or more and less than 60%
"x": 30% or more and less than 50%
"xx": less than 30%

A glass plate was coated with a clear paint using a 8 mil applicator, and
dried at a room temperature for 1 hour and subjected to forced drying at 80°C
for 1 hour to obtain a coated plate for evaluation of hot water resistance.
Subsequently, the coated plate was soaked in water at a room temperature
(about 20°C) for 1 week. Whitening of coating film thus obtained right after
the plate was taken out was checked by visual inspection and judged
according to the following standard.
"O": No whitening is observed.
"?": Whitening is slightly observed,
"x": Conspicuous whitening is observed.

A glass plate was coated with a clear paint using a 8 mil applicator, and
dried at a room temperature for 1 hour and subjected to forced drying at 80°C
for 1 hour to obtain a coated plate for evaluation of compatibility. The state of
the coating film was checked by visual inspection and judged according to the
following standard.
"O": No haze is observed.
"*": Haze is slightly observed.
V: Conspicuous haze is observed.
[0047]

A state of chalking of a coating film after an accelerated test of 2,000
hours was evaluated by visual inspection and judged according to the following
standard.
"O": No chalking is observed.
"?": Chalking is slightly observed.
"x": Conspicuous chalking is observed.

• Clear
"@": In the evaluation of weather resistance, weather resistance of a coating
film of a clear paint which contains the water-based resin composition is
improved by 3 stages or more as compared with a coating film which
does not contain the one.
"°": In the evaluation of weather resistance, weather resistance of the coating
film of a clear paint which contains the water-based resin composition is
improved by 2 stages as compared with a coating film which does not
contain the one.
"?": In the evaluation of weather resistance, weather resistance of the coating
film of a clear paint which contains the water-based resin composition is
improved by 1 stage as compared with a coating film which does not
contain the one.
"x": Weather resistance is not improved.
•Enamel
"®": In the evaluation of weather resistance, weather resistance of a coating
film of a white enamel paint which contains the water-based resin
composition is improved by 3 stages or more as compared with a
coating film which does not contain the one.
"O": In the evaluation of weather resistance, weather resistance of the coating
film of a white enamel paint which contains the water-based resin
composition is improved by 2 stages as compared with a coating film
which does not contain the one.
"?": In the evaluation of weather resistance, weather resistance of the coating
film of a white enamel paint which contains the water-based resin
composition is improved by 1 stage as compared with a coating film
which does not contain the one.
"x": Weather resistance is not improved.

Using a value of gloss at 60 degrees of this test plate as an index, the
following standard was applied for evaluation. The gloss at 60 degrees was
measured using polarized light glossmeter "VG-2000" manufactured by Nippon
Denshoku Industries Co., Ltd.
"O": 75 or more
"?": 50 or more and less than 75
"x": less than 50
[0048]
Example 11
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 45 parts of
deionized water, 5% by mass of emulsion A compounded with the rate shown
in Table 3 and 0.2 part of 28% by mass aqueous ammonia were introduced,
and the resultant mixture was heated to 75°C while inside of the reactor was
replaced by nitrogen, and an initiator solution obtained by dissolving 0.1 part of
ammonium persulfate (polymerization initiator) into 5 parts of water was added
to form a seed particle. The temperature of the resultant solution was
measured by a thermometer, and after an exothermic peak was observed, the
remainder of the emulsion A was dropped by taking 4 hours at the inside
temperature of 75°C, and the resultant system was aged for 2 hours at the
same inside temperature of 75°C to polymerize a monomer of the emulsion A
and to form a copolymer (A).
Subsequently, the system was cooled, and 28% by mass aqueous
ammonia was added at a temperature of 60°C or below till the pH of the
system became 9 to prepare a water-based resin composition. The
water-based resin composition thus obtained was used as a weather
resistance improver for water-based paints. The results of evaluation are
shown in Table 3.
[0049]
Examples 12 to 19, and 21 to 30, Comparative Examples 9, 12,14 and 15
The same procedure as in Example 1 was carried out to prepare
water-based resin compositions using the emulsion A compounded with the
rate shown in Tables 3 to 5.
The results of evaluation are shown in Tables 3 to 5.
Example 20
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 45 parts of
deionized water was introduced. Subsequently, 0.2 part of 28% by mass
aqueous ammonia and 5% by mass, with respect to the sum of the emulsion of
the whole stages, measured and taken out from the emulsion A for the first
stage polymerization described in Table 5 were introduced to the reactor, and
the resultant mixture was heated to 75°C while inside of the reactor was
replaced by nitrogen, and a initiator solution obtained by dissolving 0.1 part of
ammonium persulfate (polymerization initiator) into 5 parts of water was added
to form a seed particle. The temperature of the resultant solution was
measured by a thermometer, and after an exothermic peak was observed, the
remainder of the emulsion A was dropped by taking 2 hours at the inside
temperature of 75°C, and the resultant mixture was aged for 1 hour, and then
the emulsion B was dropped by taking 2 hours at the inside temperature of
75°C. The resultant system was aged for 2 hours at the same inside
temperature of 75°C to reduce a remaining monomer and to form a copolymer
(A). Subsequently, the system was cooled and 28% by mass aqueous
ammonia was added at a temperature of 60°C or below till the pH of the
system became 9 to prepare a water-based resin composition. The results of
evaluation are shown in Table 7.
[0050]
Comparative Example 13
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 45 parts of
deionized water was introduced. Subsequently, 5% by mass, with respect to
the sum of the emulsion of the whole stages, measured and taken out from the
emulsion A for the first stage polymerization described in Table 2 was
introduced to the reactor, and the resultant mixture was heated to 75°C while
inside of the reactor was replaced by nitrogen, and an initiator solution
obtained by dissolving 0.1 part of ammonium persulfate (polymerization
initiator) into 5 parts of water was added to form a seed particle. The
temperature of the resultant solution was measured by a thermometer, and
after an exothermic peak was observed, the remainder of the emulsion A was
dropped by taking 2 hours at the inside temperature of 75°C, and the resultant
mixture was aged for 1 hour, and then 28% by mass aqueous ammonia was
added till the pH of the system became 4, and the emulsion B was dropped by
taking 2 hours at the inside temperature of 75°C. Subsequently, the resultant
system was aged for 2 hours at the same inside temperature of 75°C to reduce
a remaining monomer and to form a copolymer (A).
Subsequently, the system was cooled and 28% by mass aqueous
ammonia was added at a temperature of 60°C or below till the pH of the
system became 9 to prepare a water-based resin composition. The results of
evaluation are shown in Table 6.
Comparative Examples 8, 10 and 11
The same procedure as in Example 11 was tried to carry out emulsion
polymerization using the emulsion A compounded with the rate shown in Table
4, however, coagulated materials were generated at the stage when a seed
particle was formed by adding the initiator solution obtained by dissolving 0.1
part of ammonium persulfate (polymerization initiator) into 5 parts of water, and
stirring became difficult owing to coagulated materials generated in course of
dropping of the remainder of the emulsion A, and hence the polymerization
was stopped.
[0051]
Reference Example 1
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 45 parts of
deionized water and 5% by mass of emulsion A compounded with the rate
shown in Table 5 were introduced, and the resultant mixture was heated to
75°C while inside of the reactor was replaced by nitrogen, and an initiator
solution obtained by dissolving 0.1 part of ammonium persulfate
(polymerization initiator) into 5 parts of water was added to form a seed particle.
The temperature of the resultant solution was measured by a thermometer,
and after an exothermic peak was observed, the remainder of the emulsion A
was dropped by taking 4 hours at the inside temperature of 75°C, and the
resultant system was aged for 2 hours at the same inside temperature of 75°C
to polymerize a monomer of the emulsion A and to form a copolymer (A).
Subsequently, the system was cooled and 28% by mass aqueous
ammonia was added at a temperature of 60°C or below till the pH of the
system became 9 to prepare a water-based resin composition.
[0052]
[0057]
Abbreviations in these tables represent the following compounds.
MMA: Methyl methacrylate
t-BMA: Tertiary butyl methacrylate
CHMA: Cyclohexyl methacrylate
n-BMA: Normal butyl methacrylate
n-BA: Normal butyl acrylate
2-EHA: 2-ethylhexyl acrylate
AA: Acrylic acid
UVA1: [Formula VIII]

HALS1:4-methacryloyloxy-2,2,6,6-tetramethylpiperidine
HALS2: 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine
"Adeka Reasoap SR-10": reactive anion type surfactant (trade name,
manufactured by Asahi Denka Kogyo K.K.)
"Adeka Reasoap ER-30": reactive nonion type surfactant (trade name,
manufactured byAsahi Denka Kogyo K.K.)
"Latemul B-118E": nonreactive anion type surfactant (trade name,
manufactured by Kao Corporation)
"Nonipol 200": nonreactive nonion type surfactant (trade name, manufactured
by Sanyo Chemical Industries, Ltd.)
NDM: Normal dodecyl mercaptan
[0058]
It is obvious from Tables 3 to 7 that the weather resistance improvers
for water-based paints of the present examples can realize conspicuous
improvement in weather resistance when they are added to other water-based
paints, as well as they are excellent in mechanical stability, storage stability and
polymerization stability.
Contrary to this, the weather resistance improvers for water-based
paints of the comparative examples are not excellent in polymerization stability
or storage stability, and are insufficient in at least one characteristics of
capability for improving weather resistance, water resistance, coloring property
and pigment dispersibility, even if they are polymerizable, when they are added
to other water-based paints as the weather resistance improvers for
water-based paints.
Consequently, it is obvious that the weather resistance improver for
water-based paints of the present invention is also useful as a weather
resistance improver for water-based paints, which is excellent in mechanical
stability and storage stability and has conspicuous capability for improving
weather resistance.
[0059]
Use as a weather resistance improver for thermoplastic resins
Various evaluations of the weather resistance improver for
thermoplastic resins were carried out by the following methods.
Preparation of test plate>
A plate molded article of 100 mm x 100 mm x 2 mm was made
according to a compounding ratio shown in the following Table 9 using
"ACRYPET MD" (trade name, manufactured by Mitsubishi Rayon Co., Ltd.) as
a base thermostatic resin. As a nonreactive HALS shown in Table 7, "SANOL
LS-770" (trade name, manufactured by Sankyo Lifetech Co., Ltd.) was used.
The initial mass average molecular mass (Mw) of "ACRYPET MD" was 92,000.

In a desiccator, 300 g of a weather resistance improver for
thermoplastic resins was kept at 20°C for a day, and after that, an organoleptic
examination was carried out at 20°C. The following standard was used for
judgement.
"O": Almost no odor is felt,
"x": Irritant odor or solvent smell is distinctly felt.
Compatibility test>
"O": Neither haze nor bleed is observed.
"x": Haze or bleed is observed.

The test was carried out for 3,000 hours using a sunshine carbon
weatherometer (manufactured by Suga test instruments Co., Ltd.,
"WEL-SUN-HC-B type" weather meter (black panel temperature: 63 ± 3°C;
cycle of raining: 12 minutes and irradiation: 48 minutes)), and color difference
(hereinafter, expressed as "AE") and molecular mass were measured, and the
results were judged according to the following standard.

Color difference was measured with spectroscopic color difference
meter "SE2000" manufactured by Nippon Denshoku Industries Co., Ltd.
"®": 3 or less
"O": 3 or more and less tan 5
"?": 5 or more and less than 10
"x": 10 or more

From each test plate which had been subjected to the weather
resistance test, 0.4 g of the plate was cut out in a vertical direction and put in a
sample bottle. Then, 100 g of tetrahydrofuran (THF) was added to the bottle
and kept overnight at a room temperature and used for molecular mass
measurement. The same method mentioned above was used for the
molecular mass measurement.
"O": 70% or more (Mw being 64,000 or more)
V: less than 70 (Mw being less than 64,000)
[0060]
Example 31
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 45 parts of
deionized water, and then, 0.2 part of 28% by mass aqueous ammonia and 5%
by mass of emulsion A compounded with the rate shown in Table 6 were
introduced, and the resultant mixture was heated to 75°C while inside of the
reactor was replaced by nitrogen, and a initiator solution obtained by dissolving
0.1 part of ammonium persulfate (polymerization initiator) into 5 parts of water
was added to form a seed particle. The temperature of the resultant solution
was measured by a thermometer, and after an exothermic peak was observed,
the remainder of the emulsion A was dropped by taking 4 hours at the inside
temperature of 75°C, and the resultant system was aged for 2 hours at the
same inside temperature of 75°C to polymerize a monomer of the emulsion A
and to form a copolymer emulsion.
Subsequently, the system was cooled and 25% by mass aqueous
ammonia was added at a temperature of 60°C or below till the pH of the
system became 9 to obtain dispersed emulsion of a weather resistance
improver for thermoplastic resins.
The concentration of the resultant dispersed emulsion was adjusted to
1% and average particle diameter was measured at 25°C using "Fiber-Optics
Particle Analyzer with Autosampler FPAR-1000" manufactured by Otsuka
Electronics Co., Ltd. The average particle diameter of cumulant analysis
obtained by the measurement was adopted as a primary particle diameter.
The dispersed emulsion cooled to room temperature was spray dried
with a spray dryer ("L-8 type", manufactured by Ohkawara Kakohki Co., Ltd.)
under the conditions of the inlet temperature of 170°C, the outlet temperature
of 60°C, and the number of revolution of atomizer of 25,000 rpm to recover
solid matter as the polymeric weather resistance improver. The polymeric
weather resistance improver thus obtained was observed by a scanning
electron microscope, and an average of measured particle diameters of 20
particles was adopted as a secondary particle diameter.
The results of evaluation are shown in Table 8.
Example 32
The same procedure as in Example 31 was carried out for emulsion
polymerization of emulsion (A) having the composition shown in Table 6, and
the resultant dispersed emulsion was subjected to spray drying to recover solid
matter using the same procedure as in Example 31. The results of evaluation
are shown in Table 8.
Example 33
The same procedure as in Example 31 was carried out for emulsion
polymerization of emulsion (A) having the composition shown in Table 6, and
the resultant dispersed emulsion was adjusted to 40°C, and introduced into the
same amount of 1.5% calcium acetate aqueous solution of a coagulating agent
while the mixture was stirred to coagulate the dispersed emulsion, and the
resultant mixture was kept at 70°C for 5 minutes to obtain a coagulated slurry.
The resultant coagulated slurry was dehydrated and dried, and solid matter
was recovered as a weather resistance improver for thermoplastic resins.
The results of evaluation are shown in Table 8.
Comparative Example 15
The same procedure as in Example 31 was carried out for emulsion
polymerization of emulsion (A) having the composition shown in Table 6, and
the resultant dispersed emulsion was subjected to spray drying to recover solid
matter using the same procedure as in Example 31. The results of evaluation
are shown in Table 8.
Comparative Example 16
The same procedure as in Example 31 was carried out for preparation
of emulsion (A) having the composition shown in Table 3 and for emulsion
polymerization of the emulsion (A), however, aggregation and fixation of the
system occurred after 10 minutes from the start of dropping of the emulsion (A)
and the polymerization was stopped.
Comparative Example 17
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 20 parts by
mass of 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine, 72 parts by mass
of methyl methacrylate, 8 parts by mass of n-butyl acrylate, 1 part by mass of
n-dodecyl mercaptan, and 80 parts by mass of ethyl acetate were introduced,
and nitrogen was introduced from the nitrogen introducing tube, and the
resultant mixture was heated to 50°C and stirred while inside of the reactor was
replaced by nitrogen. Subsequently, 0.3 part of azobisisobutyronitrile (AIBN)
dissolved in 20 parts of ethyl acetate was added to the mixture and stirred for 1
hour. After the stirring was finished, the resultant system was heated to 70°C,
and the reaction was carried out for 8 hours. After the polymerization was
finished, the resultant polymer was put into 1,000 parts of methanol and the
mixture was stirred by a homomixer for 30 minutes. After the stirring, the
mixture was subjected to a suction filtration using No. 2 filter paper, and the
filter residue was dried at 60°C with a circulating hot air dryer to recover solid
[matter] as the weather resistance improver for thermoplastic resins of
Comparative Example 17. In the case of Comparative Example 17, the solid
matter did not have a shape of particle because the solid matter was recovered
by reprecipitation after a solution polymerization so that evaluation of a particle
diameter of primary particle or secondary particle was impossible. The results
of evaluation are shown in Table 8.
Comparative Example 18
To a reactor flask equipped with a stirrer, a condenser, a temperature
control system, a dropping pump and a nitrogen-introducing tube, 10 parts by
mass of 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine, 77 parts by mass
of methyl methacrylate, 8 parts by mass of n-butyl acrylate, 5 parts by mass of
acrylic acid, 1 part by mass of n-dodecyl mercaptan, and 80 parts by mass of
ethyl acetate were introduced, and nitrogen was introduced from the nitrogen
introducing tube, and the resultant mixture was heated to 50°C and stirred
while inside of the reactor was replaced by nitrogen. Subsequently, 0.3 part
of azobisisobutyronitrile (AIBN) dissolved in 20 parts of ethyl acetate was
added to the mixture and stirred for 1 hour. After the stirring was finished, the
resultant system was heated to 70°C, and the reaction was carried out for 8
hours. After the polymerization was finished, the resultant polymer was put
into 1,000 parts of methanol and the mixture was stirred by a homomixer for 30
minutes. After the stirring, the mixture was subjected to a suction filtration
using No. 2 filter paper, and the filter residue was dried at 60°C with a
circulating hot air dryer to recover solid matter as the weather resistance
improver for thermoplastic resins of Comparative Example 18.
In the case of Comparative Example 18 as well as in the case of Comparative
Example 17, the solid matter did not have a shape of particle because the solid
matter was recovered by reprecipitation after a solution polymerization so that
evaluation of a particle diameter of primary particle or secondary particle was
impossible. The results of evaluation are shown in Table 8.
[0062]
Abbreviations in these tables represent the following compounds.
MMA: Methyl methacrylate
n-BA: Normal butyl acrylate
AA: Acrylic acid
HALS1:4-methacryloyloxy-2,2,6,6-tetramethylpiperidine
HALS2: 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine
"Pelex OT-P": nonreactive anion type surfactant (trade name, manufactured by
Kao Corporation)
"Adeka Reasoap SR-10": reactive anion type surfactant (trade name,
manufactured by Asahi Denka Kogyo K.K.)
"Adeka Reasoap ER-30": reactive nonion type surfactant (trade name,
manufactured by Asahi Denka Kogyo K.K.)
NDM: Normal dodecyl mercaptan
[0064]
Examples 34 to 37, Comparative Examples 19 to 24
The compounded materials of Table 9, in which fixed amounts of the
weather resistance improvers for thermoplastic resins obtained in the
Examples 31, 32 and 33 and the Comparative Examples 15 and 17 were
compounded, were molded into plates each having the size of 100 mm x 100
mm x 2 mm and adopted as test plates for compatibility test, weather
resistance test, and measurement of retention of molecular mass. The initial
mass average molecular mass (Mw) based on standard polystyrene of
"ACRYPET MD" used in Table 9 was 92,000. Further, as the nonreactive
HALS shown in Table 9, "SANOL LS-770" (trade name, manufactured by
Sankyo Lifetech Co., Ltd.) mentioned above was used.
Evaluation was carried out by the following methods.

"O": Neither haze nor bleed is observed,
"x": Haze or bleed is observed.

The test was carried out for 3,000 hours using a sunshine carbon
weatherometer (manufactured by Suga test instruments Co., Ltd.,
"WEL-SUN-HC-B type" weather meter (black panel temperature: 63 ± 3°C;
cycle of raining: 12 minutes and irradiation: 48 minutes)), and color difference
(hereinafter, expressed as "AE") and molecular mass were measured, and the
results were judged according to the following standard.

Color difference was measured with spectroscopic color difference
meter "SE2000" manufactured by Nippon Denshoku Industries Co., Ltd.
"®": 3 or less
"O": 3 or more and less tan 5
"?": 5 or more and less than 10
"x": 10 or more

From each test plate which had been subjected to the weather
resistance test, 0.4 g of the plate was cut out in a vertical direction and put in a
sample bottle. Then, 100 g of tetrahydrofuran (THF) was added to the bottle
and kept overnight at a room temperature and used for molecular mass
measurement. The same method mentioned above was used for the
molecular mass measurement.
"O": 70% or more (Mw being 64,000 or more)
"x": less than 70 (Mw being less than 64,000)
It is obvious from Tables 8 and 9 that the weather resistance improvers
for thermoplastic resins of the present examples do not have odor and can
realize conspicuous improvement in weather resistance for long time when
they are added to thermoplastic resins, as well as they are excellent in
polymerization stability.
Contrary to this, the water-based resin compositions of the
Comparative Examples have a problem of odor and are not excellent in
polymerization stability, and are insufficient in at least one characteristics of
compatibility, capability for improving weather resistance, water resistance,
coloring property and retention of molecular mass, even if they are
polymerizable, when they are added to other thermoplastic resins as the
weather resistance improvers for thermoplastic resins.
[0067]
Use as a weather resistance improver for solvent-based paints
Examples 38 to 40, Comparative Examples 25 to 30
The thermoplastic resin compositions obtained in the Examples 31 to
33 and the Comparative Examples 15, 17 and 18 were used as a weather
resistance improver for solvent-based paints and evaluation was carried out.
The results are shown in Table 10.
Comparative Example 26 is an example in which a weather resistance
improver for solvent-based paints or an ultraviolet light stabilizer is not
compounded, and Comparative Example 26 is an example in which a
nonreactive HALS ("SANOL LS-292" (trade name, manufactured by Sankyo
Lifetech Co., Ltd.)) was used as an ultraviolet light stabilizer.
Various evaluations were carried out according to the following methods.
[0068]
Preparation of a clear paint>
A weather resistance improver for solvent-based paints or an ultraviolet
light stabilizer was compounded at the rate shown in Table 10 to "BR-106"
(trade name, manufactured by Mitsubishi Rayon Co., Ltd.), and the resultant
mixture was dissolved in toluene to obtain a solution with solid content of 45%.
To 200 g of the resultant resin solution, 0.02 g of "KF-69" (trade name,
manufactured by Kao Corporation) was added as a leveling agent, and the
resultant resin solution was diluted with a thinner having a 50/50 of
toluene/butyl acetate composition to have the viscosity of 15 seconds in terms
of "Ford Cup #4", and filtrated using 300 mesh nylon screen to obtain a clear
paint for evaluation. The clear paint thus obtained was coated on a steel plate
treated with zinc phosphate treatment (steel plate treated with "Bondelite #100",
thickness: 0.8 mm, 70 mm x 150 mm) by spray coating to the extent that the
thickness of the dried coating film became 50 µm, and kept at a room
temperature for 1 hour and subjected to forced drying at 80°C for 1 hour to
obtain a coated plate for the tests of compatibility, water resistance, weather
resistance and capability for improving weather resistance.

A weather resistance improver for thermoplastic resins of each
Example of 38 to 40 and each Comparative Example of 15, 17 and 18 was
compounded at the rate shown in Table 10 to "BR-106" (trade name,
manufactured by Mitsubishi Rayon Co., Ltd.), and the resultant mixture was
dissolved in toluene to obtain a solution with solid content of 45%. To 200 g of
the resultant resin solution, 0.02 g of "KF-69" (trade name, manufactured by
Kao Corporation) as a leveling agent, 46.7 g of titanium oxide "CR-97" (trade
name, manufactured by Ishihara Sangyo Kaisha, Ltd.) and 150 g of glass
beads were added and dispersion of the pigment was carried out for 30
minutes using a high-speed disperser, and the resultant mixture was diluted
with a thinner having a 50/50 of toluene/butyl acetate composition to have the
viscosity of 15 seconds in terms of "Ford Cup #4", and then the glass beads
and the like were filtrated with 300 mesh nylon screen to obtain an enamel
paint for evaluation. The enamel paint thus obtained was coated on a steel
plate treated with zinc phosphate treatment (steel plate treated with "Bondelite
#100", thickness: 0.8 mm, 70 mm x 150 mm) by spray coating to the extent that
the thickness of the dried coating film became 50 µm, and kept at a room
temperature for 1 hour and subjected to forced drying at 80°C for 1 hour to
obtain a coated plate for the tests of weather resistance, chalking and
capability for improving weather resistance.

Viscosity of a resin solution was measured according to the Gardner
type viscosity-measuring method described in JIS-K5600-2-2, 4, in which
viscosity is obtained from an ascension rate of a bubble as compared with a
standard viscosity tube.

Gloss (unit: degree) was measured with a polarized light glossmeter
"VG-2000" manufactured by Nippon Denshoku Industries Co., Ltd. Gloss of a
sample before the test is shown in Table 8 as an initial gloss.

A glass plate was coated with a clear paint using a 8 mil applicator, and
dried at a room temperature for 1 hour and subjected to forced drying at 80°C
for 1 hour to obtain a coated plate for evaluation of compatibility. The state of
the coating film was checked by visual inspection and judged according to the
following standard.
"°": No haze is observed.
"?": Haze is slightly observed.
"x": Conspicuous haze is observed.

A glass plate was coated with a clear paint using a 8 mil applicator, and
dried at a room temperature for 1 hour and subjected to forced drying at 80°C
for 1 hour to obtain a coated plate for evaluation of water resistance.
Subsequently, the coated plate was soaked in water at a room temperature
(about 20°C) for 1 week. Whitening of the coating film right after the plate was
taken out was checked by visual inspection and judged according to the
following standard.
"O": Whitening is not observed,
"x": Whitening is observed.
[0069]

The test was carried out with a test plate using a sunshine carbon
weatherometer (manufactured by Suga test instruments Co., Ltd.,
"WEL-SUN-HC-B type" weather meter (black panel temperature: 63 ± 3°C;
cycle of raining: 12 minutes and irradiation: 48 minutes)). Time at which gloss
retention of the test plate became less than 70% was checked at every 500
hours in the first 2,000 hours and at every 1,000 hours from 2,000 hours, and
was adopted as a retention time of weather resistance of the test plate sample,
and the weather resistance of the test plate sample was judged according to
the following standard.
"®": Retention time of weather resistance is 4,000 hours or more.
"°": Retention time of weather resistance is 3,000 hours or more and less than
4,000 hours.
"?": Retention time of weather resistance is 2,000 hours or more and less than
3,000 hours.
"x": Retention time of weather resistance is 1,500 hours or more and less than
2,000 hours.
"xx": Retention time of weather resistance is less than 1,500 hours.

A state of chalking of a coating film after an accelerated test of 3,000
hours was checked by visual inspection and judged according to the following
standard.
"O": No chalking is observed.
"?": Chalking is slightly observed,
"x": Conspicuous chalking is observed.

• Clear
"®": In the evaluation of weather resistance, weather resistance of a coating
film of a clear paint which contains the weather resistance improver for
solvent-based paints is improved by 4 stages or more as compared with
a coating film which does not contain the one.
"O": in the evaluation of weather resistance, weather resistance of the coating
film of a clear paint which contains the weather resistance improver for
solvent-based paints is improved by 3 stages as compared with a coated
film which does not contain the one.
"?": In the evaluation of weather resistance, weather resistance of the coating
film of a clear paint which contains the weather resistance improver for
solvent-based paints is improved by 2 stages as compared with a coated
film which does not contain the one.
"x": Weather resistance of the coating film of a clear paint which contains the
weather resistance improver for solvent-based paints is improved only by
1 stage or improvement of weather resistance is not observed.
•Enamel
"®": In the evaluation of weather resistance, weather resistance of a coating
film of a white enamel paint which contains the weather resistance
improver for solvent-based paints is improved by 3 stages or more as
compared with a coated film which does not contain the one.
"O": In the evaluation of weather resistance, weather resistance of the coating
film of a white enamel paint which contains the weather resistance
improver for solvent-based paints is improved by 2 stages as compared
with a coated film which does not contain the one.
"?": In the evaluation of weather resistance, weather resistance of the coating
film of a white enamel paint which contains the weather resistance
improver for solvent-based paints is improved by 1 stage as compared
with a coated film which does not contain the one.
"x": Weather resistance is not improved.
[0070]
improvement in weather resistance for long time when they are added to other
solvent-based paints, as well as they are excellent in polymerization stability.
Contrary to this, the resin compositions of the Comparative Examples
are out of the specified compositional range of the present invention, and have
a problem in polymerization stability, and are insufficient in at least one
characteristics of compatibility, capability for improving weather resistance,
water resistance and retention of molecular mass, even if they are
polymerizable, when they are added to other solvent-based paints as the
weather resistance improvers for solvent-based paints.
Consequently, it is obvious that the weather resistance improver for
solvent-based paints of the present invention is excellent in polymerization
stability and also useful as a weather resistance improver for solvent-based
paints, which has conspicuous capability for improving weather resistance.
INDUSTRIAL APPLICABILITY
[0072]
The water-based resin composition of the present invention can realize
weather resistance for a long time as a water-based paint and can be used for
a surface finish of various materials such as cement mortars, slate plates,
plaster boards, extruded molded articles, foam concretes, metal, glass,
ceramic tile, asphalt, wood, water resistant rubber, plastics and calcium-silicate
base materials.
By adding a weather resistance improver of the present invention to a
water-based paint, weather resistance of a coating film of the water-based
paint can be improved for a long time.
Further, a resin composition obtained by recovering solid matter in the
water-based resin composition of the present invention can be used effectively
as a weather resistance improver for thermoplastic resins, which can improve a
weather resistance for a long time, by adding to an acrylic resin, a vinyl
chloride resin, a polyethylene resin, a polypropylene resin, a polystyrene resin,
an ABS resin, a polyamide resin, a polyester resin, a polycarbonate resin or the
like which is used for interiors or exteriors of automobiles, exterior building
materials, films for agricultural application, coatings for electrical wire and the
like.
Further, the resin composition obtained by recovering solid matter in
the water-based resin composition of the present invention can also be used
as a weather resistance improver for solvent-based paints, which can improve
a weather resistance, by adding the resin composition to solvent-based paints
which are used for surface finish of various materials.
WE CLAIM:
1. A water-based resin composition containing a copolymer (A) which is
obtained by carrying out emulsion polymerization of an unsaturated
monomer composed of 6 to 50 parts by mass of an ethylenically
unsaturated monomer (a), represented by the following general formula
(I), having a piperidyl group in a molecule and 50 to 94 parts by mass of
an ethylenically unsaturated monomer (b), which does not substantially
contain an ethylenically unsaturated monomer having a functional group
represented by the following formula (II), (III), or (IV) in a molecule, with
the total of the ethylenically unsaturated monomers (a) and (b) being 100
parts by mass, under the coexistence of 0.1 to 10 parts by mass of an
emulsifier and 0.1 to 10 parts by mass of a chin transfer agent

wherein R1 represents a hydrogen atom or an alkyl group having 1 to 2 carbon
atoms, X represents an oxygen atom or an imino group, Y represents a hydrogen
atom or an alkyl or alkoxyl group having 1 to 20 carbon atoms, and z represents
a hydrogen atom or a cyano group.
-COOH ....(II)
-SO3H ... (Ill)
-PO3H ... (IV)
2. The water-based resin composition as claimed in claim 1, wherein the
emulsrfier is a reactive emulsifier having a radical polymerizable
unsaturated double bond in a molecule.
3. The water-based resin composition as claimed in claim 2, wherein the
reactive emulsrfier is a reactive anion emulsrfier having a radical
polymerizable unsaturated double bond in a molecule.
4. The water-based resin composition as claimed in claim 1, wherein the
mass average molecular mass of the copolymer (A) is within the range of
from 5,000 to 300,000.
5. The water-based resin composition as claimed in claim 1, wherein
minimum film forming temperature (MFT) of the water-based resin
composition is 70°C or below.
6. The water-based resin composition as claimed in claim 1, wherein solid
content of the water-based resin composition is within the range of from
30 to 70% by mass.
7. A weather resistance improver for water-based paints comprising the
water-based resin composition as claimed in any one of claims 1 to 6.
8. A water-based paint comprising 1 to 50% by mass of the weather
resistance improver for water-based paints as claimed in claim 7 and 50 to
99% by mass of another water-based resin.
9. A water-based paint comprising the water-based resin composition as
claimed in any one of claims 1 to 6.
10. A resin composition obtained by recovering solid matter in the water-
based resin composition as claimed in any one of claims 1 to 6.
11. A weather resistance improver for thermoplastic resins comprising the
resin composition as claimed in claim 10.
12.A thermoplastic resin composition comprising the weather resistance
improver for thermoplastic resins as claimed in claim 11.


A water-based resin composition containing a copolymer (A) which is obtained by
carrying out emulsion polymerization of an unsaturated monomer composed of 6
to 50 parts by mass of an ethylenically unsaturated monomer (a), represented by
the following general formula (I), having a piperidyl group in a molecule and 50 to
94 parts by mass of an ethylenically unsaturated monomer (b), which does not
substantially contain an ethylenically unsaturated monomer having a functional
group represented by the following formula (II), (III), or (IV) in a molecule, with
the total of the ethylenically unsaturated monomers (a) and (b) being 100 parts
by mass, under the coexistence of 0.1 to 10 parts by mass of an emulsifier and
0.1 to 10 parts by mass of a chin transfer agent

wherein R1 represents a hydrogen atom or an alkyl group having 1 to 2 carbon
atoms, X represents an oxygen atom or an imino group, Y represents a hydrogen
atom or an alkyl or alkoxyl group having 1 to 20 carbon atoms, and z represents
a hydrogen atom or a cyano group.
-COOH ....(II)
-SO3H ... (Ill)
-PO3H ... (IV)

Documents:

04690-kolnp-2007-abstract.pdf

04690-kolnp-2007-claims.pdf

04690-kolnp-2007-correspondence others.pdf

04690-kolnp-2007-description complete.pdf

04690-kolnp-2007-form 1.pdf

04690-kolnp-2007-form 2.pdf

04690-kolnp-2007-form 3.pdf

04690-kolnp-2007-form 5.pdf

04690-kolnp-2007-international publication.pdf

04690-kolnp-2007-international search report.pdf

04690-kolnp-2007-others.pdf

04690-kolnp-2007-pct priority document notification.pdf

04690-kolnp-2007-pct request form.pdf

4690-KOLNP-2007-(14-09-2012)-FORM-27.pdf

4690-KOLNP-2007-ABSTRACT.pdf

4690-KOLNP-2007-AMANDED CLAIMS.pdf

4690-KOLNP-2007-CORRESPONDENCE OTHERS 1.1.pdf

4690-KOLNP-2007-CORRESPONDENCE OTHERS 1.2.pdf

4690-KOLNP-2007-CORRESPONDENCE.pdf

4690-KOLNP-2007-DESCRIPTION (COMPLETE).pdf

4690-KOLNP-2007-EXAMINATION REPORT.pdf

4690-KOLNP-2007-FORM 1.pdf

4690-KOLNP-2007-FORM 18 1.1.pdf

4690-kolnp-2007-form 18.pdf

4690-KOLNP-2007-FORM 2.pdf

4690-KOLNP-2007-FORM 26.pdf

4690-KOLNP-2007-FORM 3 1.1.pdf

4690-KOLNP-2007-FORM 3.pdf

4690-KOLNP-2007-FORM 5.pdf

4690-KOLNP-2007-FORM-27-1.1.pdf

4690-KOLNP-2007-FORM-27.pdf

4690-KOLNP-2007-GRANTED-ABSTRACT.pdf

4690-KOLNP-2007-GRANTED-CLAIMS.pdf

4690-KOLNP-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

4690-KOLNP-2007-GRANTED-FORM 1.pdf

4690-KOLNP-2007-GRANTED-FORM 2.pdf

4690-KOLNP-2007-GRANTED-SPECIFICATION.pdf

4690-KOLNP-2007-INTERNATIONAL SEARCH REPORT.pdf

4690-KOLNP-2007-OTHERS 1.1.pdf

4690-KOLNP-2007-OTHERS-1.2.pdf

4690-KOLNP-2007-PA.pdf

4690-KOLNP-2007-REPLY TO EXAMINATION REPORT 1.1.pdf

4690-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf


Patent Number 250183
Indian Patent Application Number 4690/KOLNP/2007
PG Journal Number 50/2011
Publication Date 16-Dec-2011
Grant Date 14-Dec-2011
Date of Filing 04-Dec-2007
Name of Patentee MITSUBISHI RAYON CO., LTD.
Applicant Address 6-41, KONAN 1-CHOME, MINATO-KU, TOKYO
Inventors:
# Inventor's Name Inventor's Address
1 MASAAKI KIURA C/O. TOYOHASHI PLANTS, MITSUBISHI RAYON CO., LTD. 1-2, USHIKAWADORI 4-CHOME, TOYOHASHI-SHI, AICHI 440-8601
2 TAKAHIRO MUKUDA C/O. TOYOHASHI PLANTS, MITSUBISHI RAYON CO., LTD. 1-2, USHIKAWADORI 4-CHOME, TOYOHASHI-SHI, AICHI 440-8601
3 MOTOMI TANAKA C/O. TOYOHASHI PLANTS, MITSUBISHI RAYON CO., LTD. 1-2, USHIKAWADORI 4-CHOME, TOYOHASHI-SHI, AICHI 440-8601
PCT International Classification Number C08L 33/14,C09D 5/02
PCT International Application Number PCT/JP2006/310569
PCT International Filing date 2006-05-26
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2005-357925 2005-12-12 Japan
2 2005-154109 2005-05-26 Japan
3 2006-061496 2006-03-07 Japan
4 2005-214830 2005-07-25 Japan
5 2006-054806 2006-03-01 Japan