JP2003020409A - Temperature-sensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature-sensitive resin composition suppressing sagging during coating and having excellent smoothness, gloss and water resistance of a coating film possessed by a solvent type coating. SOLUTION: This temperature-sensitive resin composition comprises an aqueous composition produced by using an oil-soluble initiator and an oil-soluble reducing agent in an aqueous medium and a polymer assuming excellent temperature responsivity having the lower limit critical codissolving temperature.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a temperature-sensitive resin composition used for paints, coating agents, sealing agents and the like. Specifically, undercoating, intermediate coating, and topcoating of paints on interior and exterior of buildings, steel structures, building materials, mortar, various concretes including lightweight cellular concrete, plastics, metalworking products such as automobiles and ships, or construction. Various types of clear coating agents, top coating agents, paints, etc. that are used as undercoats, intermediate coatings, and top coatings for finish coating materials or directly applied to building materials, mortar, concrete, steel materials, automobiles, ships, plastics, etc. The present invention relates to a temperature-sensitive resin composition used for applications, particularly a temperature-sensitive resin composition suitable for automobile coatings.

[0002]

2. Description of the Related Art Conventionally, the mainstream of paints, coating agents, sealing agents, etc. are organic solvent types, but there are risks of fire and explosion during painting, occupational safety and health, reduction of environmental pollution, resource saving, etc. From the viewpoint, the shift to aqueous is strongly desired. Although some proposals have already been made for water-based paints, it does not always mean that sagging occurs during painting, or that the excellent smoothness, gloss and water resistance of the coating film of solvent-based paints are ensured. . Among these, JP-A-7-331224
JP-A No. 2003-242242 proposes a temperature-sensitive material composed of a polymer exhibiting a temperature responsiveness having a lower critical solution temperature. Although this material suppresses sagging during coating and ensures the smoothness of the coating film surface, the improvement in gloss and water resistance of the coating film was insufficient.

[0003]

DISCLOSURE OF THE INVENTION The present invention suppresses sagging at the time of coating, and has excellent smoothness of a coating film of a solvent type coating,
It is an object to provide a temperature-sensitive resin composition having both gloss and water resistance.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have produced an oil-soluble initiator and an oil-soluble reducing agent in an aqueous medium. A temperature-sensitive resin composition containing an aqueous composition and a polymer exhibiting a temperature-responsiveness having a lower critical solution temperature, surprisingly suppresses sagging at the time of coating, and the obtained coating film is conventional. Then, they found that they exhibited unexpectedly excellent gloss, smoothness, and water resistance, and completed the present invention.

A first aspect of the invention is an aqueous composition produced using an oil-soluble initiator and an oil-soluble reducing agent in an aqueous medium,
A temperature-sensitive resin composition comprising a polymer having a lower critical solution temperature and exhibiting temperature responsiveness.
A second aspect of the invention is the temperature-sensitive resin composition according to the first aspect of the invention, wherein the aqueous composition is produced by further using a water-soluble initiator. A third aspect of the invention is the temperature-sensitive resin composition according to the first or second aspect of the invention, wherein the aqueous composition is produced by further using a reactive emulsifier. A fourth aspect of the invention is the temperature-sensitive resin composition according to any one of the first to third aspects of the invention, which further contains an emulsion polymerization composition. A fifth aspect of the invention is any one of the first to fourth aspects of the invention, in which the monomer constituting the polymer exhibiting a temperature-responsiveness having a lower critical solution temperature contains at least one N-substituted (meth) acrylamide derivative. The temperature-sensitive resin composition described. A sixth aspect of the invention is the temperature-sensitive resin composition according to any one of the first to fifth aspects of the invention, which is for use as an intermediate coating or top coating for automobiles.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The aqueous composition of the present invention may be water-soluble and / or water-dispersible, and is polymerized in an aqueous medium using an oil-soluble initiator and an oil-soluble reducing agent. Specifically, an oil-soluble initiator and an oil-soluble reducing agent are used in a water-soluble medium to perform radical polymerization, anionic polymerization, or cationic polymerization, but radical polymerization is preferred. The compounds obtained by this polymerization include conventionally known poly (meth) acrylate-based, polyvinyl acetate-based, vinyl acetate-acrylic, vinyl acetate-mixed trialkyl acetate vinyl ester-based, ethylene vinyl acetate-based, silicone-based, polybutadiene-based. Compounds such as styrene-butadiene-based, NBR-based, polyvinyl chloride-based, chlorinated polypropylene-based, polyethylene-based, polystyrene-based, vinylidene chloride-based, polystyrene- (meth) acrylate-based, styrene-maleic anhydride-based copolymers, etc. And silicone-modified acrylic, fluorine-acrylic, acrylic silicon-based, epoxy-acrylic, and other modified copolymers are also included, and one or more of these may be used.

From the viewpoint of smoothness, gloss and water resistance, the particle size of these particles is preferably 0.01 μm to 100 μm, and 0.0
More preferably, it is 5 μm to 10 μm. Specific examples of the monomer that can be used to obtain the aqueous composition include (meth) acrylic acid ester, (meth) acrylamide-based monomer, and vinyl cyanides. Examples of the (meth) acrylic acid ester include a (meth) acrylic acid alkyl ester having an alkyl portion having 1 to 18 carbon atoms, a (meth) acrylic acid hydroxyalkyl ester having an alkyl portion having 1 to 18 carbon atoms, and ethylene oxide. (Poly) oxyethylene (meth) acrylate having 1 to 100 groups, (poly) oxypropylene (meth) acrylate having 1 to 100 propylene oxide groups, and 1 to 100 ethylene oxide groups (Poly) oxyethylene di (meth) acrylate and the like.

Specific examples of alkyl (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and (meth) ) Cyclohexyl acrylate, methylcyclohexyl (meth) acrylate, dodecyl (meth) acrylate and the like can be mentioned.
Specific examples of hydroxyalkyl (meth) acrylates include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and (meth) acrylic acid 2 -Hydroxycyclohexyl, hydroxy dodecyl (meth) acrylate and the like can be mentioned.

Specific examples of the (poly) oxyethylene (meth) acrylate include ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, diethylene glycol methoxy (meth) acrylate, Examples thereof include tetraethylene glycol (meth) acrylate and tetraethylene glycol methoxy (meth) acrylate. Specific examples of (poly) oxypropylene (meth) acrylate include propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dipropylene glycol (meth) acrylate,
Methoxy (meth) acrylic acid dipropylene glycol,
Examples include tetrapropylene glycol (meth) acrylate, tetrapropylene glycol methoxy (meth) acrylate, and the like.

Specific examples of the (poly) oxyethylene di (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate,
Examples include tetraethylene glycol di (meth) acrylate and the like. As the (meth) acrylamide-based monomer,
For example, there are (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl (meth) acrylamide and the like, and examples of vinyl cyanides include (meth) acrylonitrile and the like.

Specific examples other than the above include, for example, olefins such as ethylene, propylene and isobutylene, dienes such as butadiene, haloolefins such as vinyl chloride and vinylidene chloride, vinyl acetate, vinyl propionate, and n-butyrate vinyl. , Vinyl benzoate, pt-butyl vinyl benzoate, vinyl pivalate, vinyl 2-ethylhexanoate, mixed trialkyl vinyl acetate, vinyl laurate and other carboxylic acid vinyl esters, isopropenyl acetate, isopropenyl propionate. Carboxylic acid isopropenyl esters such as, vinyl ethers such as ethyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether, styrene, aromatic vinyl compounds such as vinyltoluene, allyl acetate, allyl esters such as allyl benzoate, Lil ethyl ether, allyl glycidyl ether, allyl ethers and allyl phenyl ether, and the like.

In addition, γ- (meth) acryloxypropyltrimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinyldimethylethoxysilane, vinyldimethylmethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane,
4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, perfluoromethyl (meth) acrylate, Perfluoropropyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid 2,3
Examples also include cyclohexene oxide, allyl (meth) acrylate, acid phosphooxyethyl methacrylate, 3-chloro-2-acid phosphooxypropyl methacrylate, acrylamide methylpropane sulfonate, and divinylbenzene. These monomers may be used alone or in combination of two or more.

The aqueous composition is anionic, cationic,
It may be either nonionic or amphoteric, but anionic or cationic is preferred. It is more preferably anionic, and particularly preferably contains a carboxylic acid group from the viewpoint of enhancing water solubility. In order to have a carboxylic acid group in the aqueous composition, an ethylenically unsaturated carboxylic acid monomer is mixed with the monomer mixture used during polymerization. Specific examples thereof include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, maleic anhydride, and itaconic acid, fumaric acid, and half-esters of maleic acid.

When the aqueous composition is cationic, an ethylenically unsaturated monomer having a cationic group is mixed with the monomer mixture used for polymerization. Examples of the ethylenically unsaturated monomer having a cationic group include dimethylaminoethyl (meth) acrylate and salts thereof, diethylaminoethyl (meth) acrylate and salts thereof, dimethylaminopropyl (meth) acrylate and salts thereof, and dimethyl. Aminomethyl (meth) acrylamide and salts thereof, dimethylaminoethyl (meth) acrylamide and salts thereof, dimethylaminopropyl (meth) acrylamide and salts thereof, vinylpyridine, dimethylaminomethyl (meth) acrylamide epichlorohydrin adduct halides, dimethyl Aminopropyl (meth) acrylamide epichlorohydrin adduct halide and its alkyl sulfonate,
Examples thereof include a halide of a dimethylaminomethyl epichlorohydrin adduct of (meth) acrylic acid, a halide of a dimethylaminopropyl epichlorohydrin adduct of (meth) acrylic acid, and an alkylsulfonate thereof.

The ethylenically unsaturated monomer having a cation group is contained in the monomer mixture in an amount of 0.
It is preferably used in an amount of 5% by mass to 30% by mass, more preferably 1% by mass to 20% by mass in the monomer mixture. The aqueous composition can also be crosslinked with an amino resin. Specific examples of the amino resin include di-, tri-, tetra-, penta-, hexa-methylolmelamine and their alkyl ether compounds (wherein alkyl is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc.), urea- Formaldehyde condensate, urea-melamine co-condensate and the like can be mentioned. Of these, melamine resins are preferable, and specifically, Mitsui Cytec's Mycoat 212 (trademark) and Cymel 254.
(Trademark), Cymel 202 (trademark), Cymel 303
(Trademark), Cymel 325 (trademark), Cymel 1156
(Trademarks), Mitsui Chemicals, Inc. Uban 20N (trademark), Uban 20SB (trademark), Uban 128 (trademark), Sumitomo Chemical Co., Ltd. Sumimar M-50W (trademark), Sumimar M-40N (trademark) ), Sumimar M-
30 W (trademark) or the like is suitable.

When the aqueous composition is used after being cross-linked with the amino resin, the aqueous composition has a hydroxyl value of 20 mgKOH /
It is preferable that it contains g or more hydroxyl groups, and 25 mgKOH
/ G or more is more preferable, and 25 mgKOH / g or more and 250 mgKOH / g or less are further preferable. In order to have a hydroxyl group in the aqueous composition, a monomer having a hydroxyl group such as the above-mentioned (meth) acrylic acid hydroxyalkyl ester is mixed with the monomer mixture used during the polymerization. In addition,
The hydroxyl value is shown by the solid content mass of KOH which is equimolar to the hydroxyl group with respect to the mass of the dried aqueous composition. The number average molecular weight of the aqueous composition is 1,000 to 100,000,
It is preferably 1,000 to 50,000, and 4,
It is more preferably 000 to 50,000. It is presumed that the presence of such a component having a relatively low molecular weight ensures the adhesion of the aqueous composition to various substrates.

The aqueous composition is obtained by suspension polymerization, microsuspension polymerization, emulsion polymerization, microemulsion polymerization or miniemulsion polymerization using an oil-soluble initiator and an oil-soluble reducing agent in an aqueous medium. By using the oil-soluble initiator and the oil-soluble reducing agent, it becomes possible to obtain an aqueous composition having the above-mentioned desired molecular weight. By reducing the amount of the oil-soluble initiator and / or reducing the amount of the oil-soluble reducing agent, the molecular weight increases, and by increasing the amount of the oil-soluble initiator and / or increasing the amount of the oil-soluble reducing agent, the molecular weight decreases.
Among the above-mentioned various polymerization methods, microsuspension polymerization, microemulsion polymerization, or miniemulsion polymerization is preferable from the viewpoint of easy production of a component having a relatively low molecular weight. Further, at the time of polymerization, it is preferable to previously emulsify the monomer mixture into an aqueous medium in the presence of an emulsifier by an emulsifying machine such as a homogenizer. The addition of the oil-soluble initiator and the oil-soluble reducing agent to the polymerization reaction system is not particularly limited, and can be performed according to the method of adding the polymerization initiator in the polymerization reaction that is usually performed, but in particular, as described above, During the polymerization, the monomer mixture in an aqueous medium, in the presence of an emulsifier, when previously emulsified by an emulsifying machine such as a homogenizer, also emulsified by using this oil-soluble initiator and oil-soluble reducing agent together It is preferable to keep.

The oil-soluble initiator is a radical polymerization catalyst that radically decomposes by heat or a reducing substance to cause addition polymerization of an ethylenically unsaturated monomer. Specifically, 1,1'- Azobis (cyclohexane-1-
Carbonitrile), 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2 '-Azobis (4-methoxy-2,4-
Dimethylvaleronitrile), 2,2'-azobis [2-
(2-Imidazolin-2-yl) propane], 2,2 '
-Azobis (2,4,4-trimethylpentane), 2-
Cyano-2-propyrazoformamide, dimethyl 2,
2'-azobis (2-methylpropionate), 2,
Azo initiators such as 2′-azobis (2-hydroxymethylpropionitrile) and 1,1′-azobis (1-acetoxy-1-phenylethane), methyl ethyl ketone peroxide, cyclohexanone peroxide,
3,5,5-Trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, acetylacetone peroxide, methyl acetoacetate peroxide, 1,1-bis (t-butylperoxy)-
3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, n-butyl 4,4-bis (t-butylperoxy) valerate,
2,2-bis (t-butylperoxy) butane, 1,1
-Bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, t- Butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, t-hexyl hydroperoxide, diisopropylbenzene bishydroper Oxide, di-t-butyl peroxide, t
-Butylcumyl peroxide, dicumyl peroxide, α, α'-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-bis (t-
Butylperoxy) hexane, 2,5-dimethyl-2,
5-di (t-butylperoxy) hexyne-3, isobutyl peroxide, laurolyl peroxide, 3,
5,5-trimethylhexanoyl peroxide, succinic acid peroxide, benzoyl peroxide, 2,
4-dichlorobenzoyl peroxide, octanoyl peroxide, stearoyl peroxide, n-toluoyl peroxide, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di- 2-ethoxyethyl peroxydicarbonate, di-3-methoxybutyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate , (A, a-bis neodecanoyl peroxy) diisopropylbenzene, cumyl peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, t-hexyl peroxy neodecanoate , T-butylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane , 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t- Butyl peroxyisobutyrate, 1,1,3,3-tetramethylbutyl peroxyisopropyl monocarbonate, t-butyl peroxy laurate, t-butyl peroxy-
3,5,5-trimethylhexanoate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxyisopropyl carbonate, 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane,
Examples thereof include peroxide initiators such as t-butylperoxyacetate, t-hexylperoxybenzoate, t-butylperoxybenzoate and bis (t-butylperoxy) isophthalate. Moreover, these 2 or more types can also be used in combination. The amount used is usually 0.1 to 10 parts by mass based on 100 parts by mass of the total amount of the monomers used for producing the aqueous composition.

As the oil-soluble reducing agent, n-butanethiol, n-pentanethiol, n-hexanethiol, n
-Heptanethiol, n-octanethiol, 2-ethylhexanethiol, n-nonanethiol, n-decanethiol, n-undecanethiol, n-dodecanethiol, t-dodecanethiol, benzenethiol, α-
Thiols such as toluene thiol are preferable, and in addition to these, oil-soluble compounds containing groups such as —SO ₂ H, —NHNH ₂ , and —COCH (OH) — can be mentioned. Also,
It is also possible to use a combination of two or more of these. The amount used is usually 0.1 to 10 parts by mass based on 100 parts by mass of the total amount of the monomers used for producing the aqueous composition.

Suspension polymerization, microsuspension polymerization of aqueous compositions,
In emulsion polymerization, microemulsion polymerization or miniemulsion polymerization, it is preferable to use an emulsifier for polymerization.
When the aqueous composition is anionic, it is preferable to use an anionic surfactant and / or a nonionic surfactant. Examples of the anionic surfactant include fatty acid soap, alkyl sulfonate, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate, and polyoxyethylene alkyl aryl sulfate.

[0021] Further, for example, Sanyo Kasei Co., Ltd. Eleminor JS-2 (trademark), Eleminor JS-5 (trademark), Kao Corporation Latemuru S-120 (trademark), Latemuru S-180A (trademark), Latemur S-180 (trademark), Dai-ichi Kogyo Seiyaku Co., Ltd. Aqualon HS-10 (trademark), Asahi Denka Kogyo Co., Ltd. ADEKA REASOAP SE-10
25N (trademark), a salt of methacrylic acid sulfoalkyl ester, a salt of p-styrenesulfonic acid, Asahi Denka Kogyo Co., Ltd. ADEKA rear soap SDX-730 (trade name),
It is also possible to use a reactive emulsifier such as an ammonium salt having a phosphoric acid ester group such as ADEKA REASOAP SDX-731 (trade name) or ADEKA REASOAP SDX-334 (trade name), sodium salt, or potassium salt.

Examples of the nonionic surfactant include, for example,
Examples thereof include polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan fatty acid ester, and oxyethyleneoxypropylene block copolymer. When the aqueous composition is cationic, a cationic surfactant and / or a nonionic surfactant is used. Examples of the cationic surfactant include, for example, laurylamine hydrochloride, alkylbenzyldimethylammonium chloride, lauryltrimethylammonium chloride, alkylammonium hydroxide,
Examples thereof include polyoxyethylene alkylamine. Further, as the nonionic surfactant, for example,
Examples thereof include polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan fatty acid ester, and oxyethyleneoxypropylene block copolymer.

The amount of these surfactants used is preferably 0.05 to 20% by mass based on the solid content of the aqueous composition. Further, among the above surfactants, it is preferable to use a reactive emulsifier, and in this case, the amount used is
0.5 to 5 mass% of the solid content of the aqueous composition is preferable, and 1
Is more preferably 3% by mass.

The aqueous composition of the present invention solubilizes at least a part of the polymer by adding an alkali and / or an organic solvent if it is anionic and by adding an acid and / or an organic solvent if it is cationic. It can also be obtained by doing. Examples of the alkali used for such solubilization treatment include sodium hydroxide, potassium hydroxide, sodium hydrogen carbonate, organic amines, ammonia and the like, particularly from the viewpoint of improving the water resistance of the coating film after drying. , Monoethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, diethanolamine, Nn-butyldiethanolamine, triisopropanolamine, and morpholines such as morpholine and 4-morpholinoethanol are preferable. Of these, ammonia is preferred as the volatile alkali component. Examples of the acid include hydrochloric acid, sulfuric acid, nitric acid, methanesulfonic acid, p-toluenesulfonic acid, acetic acid, lactic acid, hydroxyacetic acid and the like. The addition of alkali or acid may be performed before the polymerization, during the polymerization, or after the polymerization. In addition, in the solubilization treatment, the organic solvent may be supplementarily used when the solubilization is insufficient by only adding an alkali or an acid, or may be solubilized only by the organic solvent. Examples of the organic solvent used include CS-12 (Chisso Corporation)
Manufactured), ethylene glycol monobutyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol mono-2-ethylhexyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol mono Butyl ether acetate, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether,
Dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, benzyl alcohol, dimethyl glutarate, isopropyl glutarate and the like can be mentioned. The addition of the organic solvent may be before the polymerization, during the polymerization, or after the polymerization, like the addition of the alkali or the acid.
Particularly for the purpose of maintaining long-term dispersion stability, the pH of the aqueous composition is adjusted to 3 to 10 by using the above alkaline component or acid component.
It is preferable to adjust to the range.

In the production of the aqueous composition, a water-soluble initiator can be used in addition to the oil-soluble initiator and the oil-soluble reducing agent. As the water-soluble initiator, water-soluble persulfates, peroxides, azobis compounds and the like can be used. As examples thereof, potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, t-butylperoxymaleic acid, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [ 2- (5-Methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2 ′
-Azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis {2-methyl-N
-[1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (2-methylpropionamide) dihydrate and the like.

The temperature-sensitive resin composition of the present invention can contain an emulsion polymerization composition. As a method of containing the emulsion polymerization composition, the emulsion polymerization is continuously performed after the polymerization of the aqueous composition using the oil-soluble initiator and the oil-soluble reducing agent, and the mixture of the obtained aqueous composition and the emulsion polymerization composition. May be mixed with a polymer exhibiting temperature responsiveness described below, or the emulsion polymerization composition obtained separately from the aqueous composition may be mixed with the aqueous composition and a polymer exhibiting temperature responsiveness. Alternatively, both may be performed.

Any emulsion polymerization composition may be used as long as it is obtained by a known method, but preferably it is radically polymerized in a water-based medium using a water-soluble initiator. The compounds obtained by this polymerization include conventionally known poly (meth) acrylate-based, polyvinyl acetate-based, vinyl acetate-acrylic, vinyl acetate-mixed trialkyl acetate vinyl ester-based, ethylene vinyl acetate-based, silicone-based, polybutadiene-based. Compounds such as styrene-butadiene-based, NBR-based, polyvinyl chloride-based, chlorinated polypropylene-based, polyethylene-based, polystyrene-based, vinylidene chloride-based, polystyrene- (meth) acrylate-based, styrene-maleic anhydride-based copolymers, etc. And silicone-modified acrylic, fluorine-acrylic, acrylic silicon-based, epoxy-acrylic, and other modified copolymers are also included, and one or more of these may be used.

The particle size of these particles is preferably 0.01 μm to 100 μm in view of smoothness, gloss and water resistance, and 0.0
More preferably, it is 5 μm to 10 μm. The monomer that can be used to obtain the emulsion-polymerized composition is specifically (meth) acrylic acid ester, (meth) acrylamide-based monomer,
Examples thereof include vinyl cyanides. As an example of the (meth) acrylic acid ester, the alkyl part has 1 to 18 carbon atoms.
Of (meth) acrylic acid alkyl ester, (meth) acrylic acid hydroxyalkyl ester having 1 to 18 carbon atoms in the alkyl part, and 1 to 100 ethylene oxide groups.
(Poly) oxyethylene (meth) acrylate, the number of propylene oxide groups is 1 to 100 (poly) oxypropylene (meth) acrylate, and the number of ethylene oxide groups is 1 to 100 (poly) oxyethylene di (Meth) acrylate etc. are mentioned.

Specific examples of alkyl (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and (meth ) Cyclohexyl acrylate, methylcyclohexyl (meth) acrylate, dodecyl (meth) acrylate and the like can be mentioned.
Specific examples of hydroxyalkyl (meth) acrylates include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and (meth) acrylic acid 2 -Hydroxycyclohexyl, hydroxy dodecyl (meth) acrylate and the like can be mentioned.

Specific examples of (poly) oxyethylene (meth) acrylate include ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, diethylene glycol methoxy (meth) acrylate, Examples thereof include tetraethylene glycol (meth) acrylate and tetraethylene glycol methoxy (meth) acrylate. Specific examples of (poly) oxypropylene (meth) acrylate include propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dipropylene glycol (meth) acrylate,
Methoxy (meth) acrylic acid dipropylene glycol,
Examples include tetrapropylene glycol (meth) acrylate, tetrapropylene glycol methoxy (meth) acrylate, and the like.

Specific examples of (poly) oxyethylene di (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate,
Examples include tetraethylene glycol di (meth) acrylate and the like. As the (meth) acrylamide-based monomer,
For example, there are (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl (meth) acrylamide and the like, and examples of vinyl cyanides include (meth) acrylonitrile and the like.

Specific examples other than the above include, for example, olefins such as ethylene, propylene and isobutylene, dienes such as butadiene, haloolefins such as vinyl chloride and vinylidene chloride, vinyl acetate, vinyl propionate, n-butyrate vinyl. , Vinyl benzoate, pt-butyl vinyl benzoate, vinyl pivalate, vinyl 2-ethylhexanoate, mixed trialkyl vinyl acetate, vinyl laurate and other carboxylic acid vinyl esters, isopropenyl acetate, isopropenyl propionate. Carboxylic acid isopropenyl esters such as, vinyl ethers such as ethyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether, styrene, aromatic vinyl compounds such as vinyltoluene, allyl acetate, allyl esters such as allyl benzoate, Allyl ethers such as ryl ethyl ether, allyl glycidyl ether and allyl phenyl ether, and γ- (meth) acryloxypropyltrimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinyldimethylethoxysilane, vinyldimethylmethoxysilane. , Vinyltrimethoxysilane, vinyltriethoxysilane, 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,
2,2,6,6-pentamethylpiperidine, perfluoromethyl (meth) acrylate, perfluoropropyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, ( Glycidyl (meth) acrylate, 2,3-cyclohexene oxide (meth) acrylate, allyl (meth) acrylate, acid phosphooxyethyl methacrylate, methacrylic acid 3
-Chloro-2-acid phosphooxypropyl, acrylamide methylpropane sulfonate, divinylbenzene and the like. These monomers may be used alone or in combination of two or more.

The emulsion-polymerized composition may be any of anionic, cationic, nonionic and amphoteric. However, when the aqueous composition is anionic, the emulsion-polymerized composition is also anionic. The same ionic as the aqueous composition is preferred. It is preferable that the anionic emulsion-polymerized composition particularly contains a carboxylic acid group from the viewpoint of increasing water solubility. In order to have a carboxylic acid group in the emulsion polymerization composition, an ethylenically unsaturated carboxylic acid monomer is mixed with the monomer mixture used at the time of polymerization. Specific examples thereof include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, maleic anhydride, and itaconic acid, fumaric acid, and half-esters of maleic acid.

The cationic emulsion polymerization composition can be obtained by mixing an ethylenically unsaturated monomer having a cationic group with the monomer mixture used for polymerization. Examples of the ethylenically unsaturated monomer having a cationic group include dimethylaminoethyl (meth) acrylate and salts thereof, diethylaminoethyl (meth) acrylate and salts thereof, dimethylaminopropyl (meth) acrylate and salts thereof, and dimethyl. Aminomethyl (meth) acrylamide and its salts, dimethylaminoethyl (meth) acrylamide and its salts, dimethylaminopropyl (meth) acrylamide and its salts, vinylpyridine, dimethylaminomethyl (meth) acrylamide epichlorohydrin adduct halides, dimethyl Aminopropyl (meth) acrylamide epichlorohydrin adduct halides and their alkylsulfonates, (meth) acrylic acid dimethylaminomethylepichlorohydrin adduct halides, (meth) acrylic Halides and alkyl sulfonic acid salts of acid dimethylaminopropyl epichlorohydrin adducts.

The ethylenically unsaturated monomer having a cationic group is added to the monomer mixture in an amount of 0.1% from the viewpoint of penetrability into the base material.
It is preferably used in an amount of 5% by mass to 30% by mass, more preferably 1% by mass to 20% by mass in the monomer mixture. When cross-linking with an amino resin such as melamine is used in the temperature-sensitive resin composition of the present invention, it is necessary that the emulsion polymerization composition also contains a hydroxyl group having a hydroxyl value of 20 mgKOH / g or more, and 25 mgKOH / g or more. Is preferred, 25 mgKOH / g or more, and 250 mg
KOH / g or less is more preferable. In order to have a hydroxyl group in the emulsion polymerization composition, a monomer having a hydroxyl group such as the above-mentioned (meth) acrylic acid hydroxyalkyl ester is mixed with the monomer mixture used during the polymerization. The hydroxyl value is shown by the mass of the solid content of KOH that is equimolar to the hydroxyl group with respect to the mass of the dried emulsion polymerization composition.

Upon polymerization of the emulsion-polymerized composition, it is preferable that the monomer mixture is previously emulsified in an aqueous medium in the presence of an emulsifier with an emulsifying machine such as a homogenizer. As the water-soluble initiator for emulsion polymerization, water-soluble persulfates, peroxides, azobis compounds and the like can be used. Examples thereof include potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, t-butylperoxymaleic acid, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis. [2- (5-Methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2 ′
-Azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis {2-methyl-N
-[1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (2-methylpropionamide) dihydrate and the like.

In the case of producing an emulsion polymerization composition, it is preferable to use an emulsifier for polymerization. When the emulsion-polymerized composition is anionic, it is preferable to use an anionic surfactant and / or a nonionic surfactant. Examples of the anionic surfactant include fatty acid soap, alkyl sulfonate, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate, and polyoxyethylene alkyl aryl sulfate. Also,
For example, Sanyo Kasei Co., Ltd. eleminol JS-2 (trademark), eleminol JS-5 (trademark), Kao Co., Ltd. latemuru S-120 (trademark), latemuru S-180A (trademark), latemuru S-180 ( Trademark), Dai-ichi Kogyo Seiyaku Co., Ltd. Aqualon HS-10 (trademark), Asahi Denka Kogyo Co., Ltd. ADEKA rear soap SE-1025N (trademark),
Methacrylic acid sulfoalkyl ester salt, p-styrene sulfonic acid salt, Asahi Denka Kogyo Co., Ltd. ADEKA rear soap SDX-730 (trade name), ADEKA rear soap SD
X-731 (trade name), ADEKA rear soap SDX-33
It is also possible to use a reactive emulsifier such as ammonium salt, sodium salt or potassium salt having a phosphoric acid ester group such as 4 (trade name).

Examples of the nonionic surfactant include, for example,
Examples thereof include polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan fatty acid ester, and oxyethyleneoxypropylene block copolymer. When the emulsion polymerization composition is cationic, it is preferable to use a cationic surfactant and / or a nonionic surfactant. Examples of the cationic surfactant include laurylamine hydrochloride, alkylbenzyldimethylammonium chloride, lauryltrimethylammonium chloride, alkylammonium hydroxide, polyoxyethylenealkylamine and the like. Examples of nonionic surfactants include polyoxyethylene alkylaryl ethers, polyoxyethylene sorbitan fatty acid esters, and oxyethyleneoxypropylene block copolymers.

The amount of these surfactants used is preferably 0.05 to 20% by mass, more preferably 0.1 to 5% by mass, based on the solid content of the emulsion polymerization composition. The emulsion-polymerized composition is obtained by solubilizing at least a part of the polymer by adding an alkali and / or an organic solvent if it is anionic and by adding an acid and / or an organic solvent if it is cationic. You can also As the alkali used for such solubilization treatment, sodium hydroxide,
Potassium hydroxide, sodium hydrogen carbonate, organic amines,
Ammonia and the like can be mentioned, and in particular, from the viewpoint of improving the water resistance of the coating film after drying, monoethanolamine, N, N
-Dimethylethanolamine, N, N-diethylethanolamine, diethanolamine, Nn-butyldiethanolamine, triisopropanolamine, and morpholines such as morpholine and 4-morpholinoethanol are preferable. Of these, ammonia is preferred as the volatile alkali component.

Examples of the acid include hydrochloric acid, sulfuric acid, nitric acid, methanesulfonic acid, p-toluenesulfonic acid, acetic acid, lactic acid, hydroxyacetic acid and the like. The addition of alkali or acid may be performed before the polymerization, during the polymerization, or after the polymerization. In addition, in the solubilization treatment, the organic solvent may be supplementarily used when the solubilization is insufficient by only adding an alkali or an acid, or may be solubilized only by the organic solvent. Examples of the organic solvent used include CS-12 (Chisso Corporation)
Manufactured), ethylene glycol monobutyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol mono-2-ethylhexyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol mono Butyl ether acetate, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether,
Dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, benzyl alcohol, dimethyl glutarate, isopropyl glutarate and the like can be mentioned. The addition of the organic solvent may be before the polymerization, during the polymerization, or after the polymerization, like the addition of the alkali or the acid.
Especially for the purpose of maintaining long-term dispersion stability, the pH of the aqueous composition is adjusted to 3 to 1 by using the above alkaline component or acid component.
It is preferable to adjust the range to 0.

The temperature-sensitive resin composition of the present invention contains, in addition to the above-mentioned aqueous composition, a polymer having a lower critical solution temperature and exhibiting temperature responsiveness. Surprisingly, a feeling prepared by blending both the above-mentioned aqueous composition produced using an oil-soluble initiator and an oil-soluble reducing agent in an aqueous medium and a polymer exhibiting a lower critical solution temperature The thermosetting resin composition suppresses sagging at the time of coating, and the resulting coating film exhibits excellent gloss, smoothness, and water resistance that cannot be predicted in the past.

The lower critical eutectic temperature is the critical temperature at which the polymer transitions from the state of being dissolved in water to the state of being insoluble. Below this temperature, the polymer is in a hydrated state and the molecular chains are spread. Further, at a temperature higher than this temperature, dehydration occurs and molecular chains aggregate. This change is reversible.
The temperature-responsive polymer having a lower critical solution temperature is a homopolymer of a temperature-responsive monomer, a copolymer of two or more of the monomers, or one of the monomers. It is a copolymer of the above and at least one other monomer that does not exhibit temperature responsiveness.

Among these, in that the lower critical eutectic temperature can be changed, the co-weight of one or more monomers exhibiting temperature responsiveness and one or more other monomers not exhibiting temperature responsiveness Coalescence is preferred. That is, the lower critical solution temperature can be moved to a low temperature side by copolymerization with a hydrophobic monomer, and can be moved to a high temperature side by copolymerization with a hydrophilic monomer. The temperature-responsive polymer of the present invention is radical-polymerized, anionic-polymerized, or cationic-polymerized, but radical-polymerization is preferred from the viewpoint that a safer aqueous reaction is possible. It is obtained by suspension polymerization, microsuspension polymerization, emulsion polymerization, microemulsion polymerization, miniemulsion polymerization or the like using a water-soluble initiator in an aqueous medium.

When the polymer exhibiting temperature responsiveness is a copolymer, the type of copolymerization may be random copolymerization or block copolymerization. A polymer exhibiting temperature response is
When containing other monomers that do not exhibit temperature responsiveness,
The proportion of the monomer exhibiting temperature responsiveness is 50% by mass or more, preferably 60% by mass or more, and more preferably 70% by mass or more of the whole polymer exhibiting temperature responsiveness.

Examples of the monomer exhibiting temperature response include N-substituted (meth) acrylamide derivatives and vinyl methyl ether. Examples of the N-substituted (meth) acrylamide derivative include N-isopropyl (meth) acrylamide, Nn-propyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-cyclopropyl (meth) acrylamide, N, N-diethyl. (Meth) acrylamide, N-methyl-N-ethyl (meth) acrylamide, N-methyl-N-isopropyl (meth) acrylamide, N-methyl-Nn-propyl (meth) acrylamide, N-acryloylpiperidine and the like can be mentioned. To be

As the other monomer which does not exhibit temperature responsiveness, any monomer may be used as long as it can be copolymerized with the monomer which exhibits temperature responsiveness. Substituted (meth) acrylamide monomers, vinyl cyanides, ethylenically unsaturated carboxylic acid monomers,
Examples include ethylenically unsaturated monomers having a cationic group. Examples of the (meth) acrylic acid ester include a (meth) acrylic acid alkyl ester having an alkyl portion having 1 to 18 carbon atoms, a (meth) acrylic acid hydroxyalkyl ester having an alkyl portion having 1 to 18 carbon atoms, and ethylene oxide. (Poly) oxyethylene (meth) acrylate having 1 to 100 groups, (poly) oxypropylene (meth) acrylate having 1 to 100 propylene oxide groups, and 1 to 100 ethylene oxide groups (Poly) oxyethylene di (meth) acrylate and the like.

Specific examples of alkyl (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and (meth ) Cyclohexyl acrylate, methylcyclohexyl (meth) acrylate, dodecyl (meth) acrylate and the like can be mentioned.
Specific examples of hydroxyalkyl (meth) acrylates include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and (meth) acrylic acid 2 -Hydroxycyclohexyl, hydroxy dodecyl (meth) acrylate and the like can be mentioned.

Specific examples of the (poly) oxyethylene (meth) acrylate include ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, diethylene glycol methoxy (meth) acrylate, Examples thereof include tetraethylene glycol (meth) acrylate and tetraethylene glycol methoxy (meth) acrylate. Specific examples of (poly) oxypropylene (meth) acrylate include propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dipropylene glycol (meth) acrylate,
Methoxy (meth) acrylic acid dipropylene glycol,
Examples include tetrapropylene glycol (meth) acrylate, tetrapropylene glycol methoxy (meth) acrylate, and the like.

Specific examples of the (poly) oxyethylene di (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate,
Examples include tetraethylene glycol di (meth) acrylate and the like. Examples of N-unsubstituted (meth) acrylamide monomers include (meth) acrylamide, and examples of vinyl cyanides include (meth) acrylonitrile.

Examples of the ethylenically unsaturated carboxylic acid monomer include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, maleic anhydride, and itaconic acid, fumaric acid, and half esters of maleic acid. . Specific examples of the ethylenically unsaturated monomer having a cationic group include dimethylaminoethyl (meth) acrylate and salts thereof, diethylaminoethyl (meth) acrylate and salts thereof, dimethylaminopropyl (meth) acrylate and salts thereof. Salt, vinyl pyridine, halide of dimethylaminomethyl epichlorohydrin (meth) acrylate adduct,
Examples thereof include halides of dimethylaminopropyl epichlorohydrin (meth) acrylate adducts and alkyl sulfonates thereof.

Specific examples other than the above include, for example, olefins such as ethylene, propylene and isobutylene, dienes such as butadiene, haloolefins such as vinyl chloride and vinylidene chloride, vinyl acetate, vinyl propionate, and n-butyrate vinyl. , Vinyl benzoate, pt-butyl vinyl benzoate, vinyl pivalate, vinyl 2-ethylhexanoate, mixed trialkyl vinyl acetate, vinyl laurate and other carboxylic acid vinyl esters, isopropenyl acetate, isopropenyl propionate. Carboxylic acid isopropenyl esters such as, vinyl ethers such as ethyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether, styrene, aromatic vinyl compounds such as vinyltoluene, allyl acetate, allyl esters such as allyl benzoate, Allyl ethers such as ryl ethyl ether, allyl glycidyl ether and allyl phenyl ether, and γ- (meth) acryloxypropyltrimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinyldimethylethoxysilane, vinyldimethylmethoxysilane. , Vinyltrimethoxysilane, vinyltriethoxysilane, 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,
2,2,6,6-pentamethylpiperidine, perfluoromethyl (meth) acrylate, perfluoropropyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, ( Glycidyl (meth) acrylate, 2,3-cyclohexene oxide (meth) acrylate, allyl (meth) acrylate, acid phosphooxyethyl methacrylate, methacrylic acid 3
-Chloro-2-acid phosphooxypropyl, acrylamide methylpropane sulfonate, divinylbenzene and the like. These monomers may be used alone or in combination of two or more.

The polymer exhibiting temperature response is preferably a copolymer obtained by crosslinking with a polyfunctional monomer. The polyfunctional monomer is a monomer that three-dimensionally crosslinks the copolymer, and has two or more polymerizable ethylenically unsaturated groups in the molecule. As a result, when the paint becomes the state of the coating film,
The temperature-sensitive resin composition of the present invention has an advantage of maintaining the state of particles in the coating film. As the polyfunctional monomer, methylenebisacrylamide, ethylene glycol di (meth) acrylate, triethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, pentaerythritol triacrylate, divinylbenzene. And the like, and one kind or two or more kinds can be used.

In the temperature-sensitive resin composition of the present invention, the components usually added to paints, such as viscosity adjusting agents, pH adjusting agents, antifoaming agents, pigments, fillers, dispersants, dyes, preservatives, It is not possible to mix surfactants, heat stabilizers, UV absorbers, antioxidants, light stabilizers, flame retardants, organic solvents, wetting agents, thickeners, plasticizers, film forming aids, rust preventives, etc. It is optional. These are dispersed using, for example, a kneading machine such as an attritor or a sand mill, and adjusted to have a predetermined viscosity.

The temperature-sensitive resin composition of the present invention is used for paints, coating agents, sealing agents and the like. Specifically, interior and exterior construction, steel structures, building materials, mortar, various concretes including lightweight cellular concrete, plastic,
It is used as an undercoat, an intermediate coat, and an overcoat for paints on metal products such as automobiles and ships, or as an undercoat, an intermediate coat, and an overcoat for building finish coating materials, or building materials,
It is used in various applications as a clear coating agent, top coating agent, paint, etc. that is directly applied to mortar, concrete, steel materials, automobiles, ships, plastics, etc. Among the above, it is particularly used as an intermediate coating or top coating for automobiles.

In an automobile coating, an aqueous metallic base containing a metallic pigment was applied as an overcoat on a coated plate which was undercoated and intermediately coated, and then the coating was wet-on-wet coating and clear coating was repeated without curing. However, a so-called two-coat / one-bake method is used in which the aqueous metallic base and the clear are cured together. In addition, a water-based intermediate coating is applied on the electrodeposited coated plate, a water-based base coating is applied before it is cured, and then a clear coating is applied before the curing. Water-based paints are also used as the middle coat and top coat base of the so-called 3 coat 1 bake system, in which a clear coat and a clear coat are simultaneously baked. The temperature-sensitive resin composition of the present invention can also be used in the above-mentioned two-coat / one-bake or three-coat / one-bake system intermediate coating and / or topcoat base coating.

Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the technical scope and embodiments of the present invention are not limited to the Examples. Examples, comparative examples, production examples,
The methods for measuring various physical properties used in Reference Examples are as follows. [1] Particle size measurement: Ultrafine particle size analyzer (UPA)
It was used. Model: Nikkiso Co., Ltd. Microtrac UPA MO
DEL; 9230 [2] Number average molecular weight: determined from a polystyrene standard calibration curve using gel permeation chromatography. As a measurement sample, each sample was dissolved in tetrahydrofuran to a concentration of 0.5 to 1% by mass. (Used equipment) Liquid chromatography device: HLC-8020 manufactured by Tosoh Corporation Column: TSKgel G-5000 HXL TSKgel G-4000 HXL TSKgel G-2000 HXL manufactured by Tosoh Corporation Column temperature: 50 ° C Data processing device : Tosoh Corp. SC8010 ・ Carrier: Tetrahydrofuran

[0057]

[Production Example 1] (Aqueous composition (1)) 7 parts of water was placed in a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank and a thermometer.
Then, 100 parts by mass is added and the inside of the reaction vessel is heated to 80 ° C. To a mixed solution of 70 parts by mass of acrylic acid, 100 parts by mass of 2-hydroxyethyl methacrylate, 680 parts by mass of methyl methacrylate, 150 parts by mass of n-butyl acrylate, and 12 parts by mass of n-dodecanethiol, t-butylperoxybenzoate 25. After dissolving parts by mass, this monomer mixed liquid and water 29
0 parts by mass, 80 parts by mass of 20% aqueous solution of "Latemur S-180A" (trademark, reactive emulsifier manufactured by Kao Corporation), 2
% A mixture of 100 parts by weight of ammonium persulfate aqueous solution is made into a pre-emulsion by a homogenizer and allowed to flow into the reaction vessel from the dropping tank for 4 hours. The temperature in the reaction vessel is maintained at 83 ° C during the inflow. Hold for another 2 hours after the inflow ends. After cooling to room temperature, an aqueous composition (1) was obtained. Resin solid content 47.2%, pH 1.7, number average molecular weight is 2
It was 5,000.

[0058]

[Production Example 2] (Aqueous composition (2)) Water 6 was added to a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank and a thermometer.
Then, 100 parts by mass is added and the inside of the reaction vessel is heated to 80 ° C. Methacrylic acid 40 parts by mass, 2-hydroxyethyl acrylate 50 parts by mass, cyclohexyl methacrylate 300 parts by mass, methyl methacrylate 380 parts by mass, acrylic acid n-
After dissolving 10 parts by mass of t-butylperoxy-2-ethylhexanoate in a mixed solution of 230 parts by mass of butyl and 25 parts by mass of t-dodecanethiol, 290 parts by mass of this monomer mixed solution, 290 parts by mass of water, and "Eleminol JS- 2 ”(trademark, reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) and a mixed solution of 80 parts by mass of a 20% aqueous solution and 200 parts by mass of a 2% aqueous solution of sodium persulfate are used as a pre-emulsion solution by a homogenizer, and the mixture is put into a reaction vessel from a dropping tank. Flow for 4 hours. At the start of inflow of the pre-emulsion, 1 part by mass of sodium hyposulfite was added to the reaction vessel. The temperature in the reaction vessel was 83 ° C during the inflow.
Keep on. Hold for another 2 hours after the inflow ends. After cooling to room temperature, an aqueous composition (2) was obtained. Resin solids 47.
5%, pH 1.7, the number average molecular weight was 18,000.

[0059]

[Production Example 3] (Aqueous composition (3)) Water 6 was added to a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank and a thermometer.
00 parts are added and the inside of the reaction vessel is heated to 80 ° C. Acrylic acid 35 parts by mass, 2-hydroxyethyl methacrylate 50
After dissolving 10 parts by mass of t-butyl peroxybenzoate in a mixed solution of parts by mass, 340 parts by mass of methyl methacrylate, 75 parts by mass of n-butyl acrylate and 12 parts by mass of n-dodecanethiol, this monomer mixture solution and water 250 parts by mass, "Eleminol JS-2" (trademark, Sanyo Kasei Co., Ltd.)
18 parts by mass of 25% aqueous solution of "reactive emulsifier manufactured by K.K.", 18 parts by mass of 25% aqueous solution of "Aqualon HS-10" (trademark, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), 75 parts by mass of aqueous solution of 2% ammonium persulfate. The mixed solution of (1) is made into a pre-emulsion by a homogenizer and allowed to flow into the reaction vessel from the dropping tank for 2 hours. At the start of inflow of the pre-emulsion, 1 part by mass of sodium formaldehyde sulfoxylate dihydrate was added to the reaction vessel. The temperature in the reaction vessel is maintained at 83 ° C during the inflow. Successively, to a mixed solution of 4 parts by mass of methacrylic acid, 25 parts by mass of 2-hydroxypropyl methacrylate, 300 parts by mass of cyclohexyl methacrylate, 171 parts by mass of n-butyl acrylate and 2.0 parts by mass of n-dodecanethiol was added t-butylperm. After dissolving 10 parts by mass of oxybenzoate, 250 parts by mass of this monomer mixed liquid and water,
10 parts by mass of 25% aqueous solution of "Eleminol JS-2" (trademark, reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.), 25 of "Aqualon HS-10" (trademark, reactive emulsifier manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) % Aqueous solution of 10 parts by mass and a mixed solution of 50% by mass of a 2% aqueous solution of ammonium persulfate into a pre-emulsion by a homogenizer, and the mixture is allowed to flow into the reaction vessel from the dropping tank for 2 hours. Hold for another 2 hours after the inflow ends. After cooling to room temperature, an aqueous composition (3) was obtained. Resin solid content 4
It was 5.0%, pH 1.9, and the number average molecular weight was 31,000.

[0060]

[Production Example 4] (Composite (5) consisting of aqueous composition (4) and emulsion polymerization composition) 320 parts by mass of water was put into a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank and a thermometer. Then, the inside of the reaction vessel is heated to 80 ° C. Next, acrylic acid 2
4 parts by mass, acrylamide 4 parts by mass, methyl methacrylate 356 parts by mass, 2-ethylhexyl acrylate 416
To a mixed solution of 12 parts by mass of n-butanethiol,
-After dissolving 20 parts by mass of butyl peroxybenzoate,
432 parts by mass of this monomer mixed liquid and water, Latemur S-1
A mixed solution of 48 parts by mass of a 20% aqueous solution of 80A and 2.4 parts of ammonium persulfate is made into a pre-emulsion liquid by a homogenizer and allowed to flow into the reaction vessel from the dropping tank for 4 hours. At the start of inflow of the pre-emulsion, 1 part by mass of sodium hyposulfite was added to the reaction vessel. Hold for another 2 hours after the inflow ends. The temperature in the reaction vessel is kept at 8 during the inflow.
Keep at 3 ° C. After cooling to room temperature, a 25% aqueous solution of dimethylethanolamine was added to adjust the pH to 6 to obtain an aqueous composition (4). The resin solid content was 49.6% and the number average molecular weight was 25,000. Successively, 981 parts by mass of water was added to the above aqueous composition (4), and the inside of the reaction vessel was heated to 80%.
℃. Next, methacrylic acid 4 parts by mass, acrylamide 2 parts by mass, styrene 80 parts by mass, butyl acrylate 1
4 parts by mass, a mixed solution of 100 parts by mass of butyl methacrylate, 118.3 parts by mass of water, and 20 of Latemur S-180A.
% Aqueous solution and a mixed solution of 15 parts by mass of ammonium persulfate and 0.6 parts by mass of ammonium persulfate are made into a pre-emulsified liquid by a homogenizer and allowed to flow into the reaction vessel from the dropping tank over 1 hour. The temperature in the reaction vessel is maintained at 83 ° C during the inflow. After the inflow is completed, the temperature is maintained for 30 minutes as it is, and then a mixed solution of 0.2 parts of ammonium persulfate and 5 parts of water is inflowed over 30 minutes, and the temperature in the reaction vessel is maintained at 85 ° C. for 3 hours after the inflow. After cooling to room temperature, a complex (5) having a pH of 5.9 and a solid content of 33.3% was obtained.

[0061]

Reference Example 1 (Production Example of Aqueous Composition Not Using Oil-Soluble Reducing Agent) n in Preparation of Aqueous Composition (1) of Example 1
-Produced in the same way, but without the use of dodecanethiol. The resin solid content was 46.0%, the pH was 1.7, and the number average molecular weight was 650,000.

[0062]

Reference Example 2 (Production Example of Aqueous Composition Not Using Oil-Soluble Initiator) t when preparing the aqueous composition (1) of Example 1
-Except that no butyl peroxybenzoate is used
It was manufactured in the same way. Resin solid content 46.5%, pH
1.7, the number average molecular weight was 25,000.

[0063]

[Production Example 5] (Polymer (1) exhibiting temperature responsiveness) 1,000 parts by mass of water, SE-1025N (Asahi Denka Kogyo Co., Ltd.) were placed in a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer. (Reactive emulsifier manufactured by Co., Ltd.) 27 parts by mass of 25% aqueous solution, and JS-2 (reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) 3
56 parts by mass of an 8% aqueous solution is charged and the inside of the reaction vessel is heated to 80 ° C. To this, 28 parts by mass of a 2% aqueous solution of ammonium persulfate is added. After dissolving 4 parts by mass of acrylamide in a mixed solution of 47 parts by mass of methyl methacrylate, 33 parts by mass of butyl acrylate, and 7 parts by mass of acrylic acid, the monomer mixture is allowed to flow into the reaction vessel from the dropping tank over 30 minutes. .. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another 30 minutes after the inflow is completed. Furthermore, to 3485 parts by mass of water, 22 parts by mass of 25% SE-1025N aqueous solution, 38% by mass
Dissolve 7 parts by mass of JS-2 aqueous solution, 851 parts by mass of N-isopropylacrylamide, 53 parts by mass of 2-hydroxyethyl methacrylate, 4 parts by mass of acrylic acid, 1 part by mass of methylenebisacrylamide, and 44 parts by mass of 2% ammonium persulfate aqueous solution. The thus-prepared aqueous solution is allowed to flow into the reaction vessel from the dropping tank for 3 hours. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another hour after the inflow is completed. Thus, a polymer (1) having a resin solid content of 18.3% and a temperature response of pH 4.4 was obtained.

[0064]

[Production Example 6] (Polymer (2) exhibiting temperature responsiveness) 1,000 parts by mass of water and SE-1025N (Asahi Denka Kogyo Co., Ltd.) were placed in a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer. (Reactive emulsifier manufactured by Co., Ltd.) 27 parts by mass of 25% aqueous solution, and JS-2 (reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) 3
56 parts by mass of an 8% aqueous solution is charged and the inside of the reaction vessel is heated to 80 ° C. To this, 28 parts by mass of a 2% aqueous solution of ammonium persulfate is added. After dissolving 4 parts by mass of acrylamide in a mixed solution of 47 parts by mass of methyl methacrylate, 33 parts by mass of butyl acrylate, and 7 parts by mass of acrylic acid, the monomer mixture is allowed to flow into the reaction vessel from the dropping tank over 30 minutes. .. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another 30 minutes after the inflow is completed. Furthermore, to 3485 parts by mass of water, 22 parts by mass of 25% SE-1025N aqueous solution, 38% by mass
Dissolve 7 parts by mass of JS-2 aqueous solution, 797 parts by mass of N-isopropylacrylamide, 106 parts by mass of 2-hydroxyethyl methacrylate, 4 parts by mass of acrylic acid, 1 part by mass of methylenebisacrylamide, and 44 parts by mass of 2% ammonium persulfate aqueous solution. The thus-prepared aqueous solution is allowed to flow into the reaction vessel from the dropping tank for 3 hours. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another hour after the inflow is completed. Thus, a polymer (2) having a resin solid content of 18.3% and a temperature response of pH 4.4 was obtained.

[0065]

[Production Example 7] (Polymer (3) exhibiting temperature responsiveness) 1,000 parts by mass of water, SE-1025N (Asahi Denka Kogyo Co., Ltd.) were placed in a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer. (Reactive emulsifier manufactured by Co., Ltd.) 27 parts by mass of 25% aqueous solution, and JS-2 (reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) 3
56 parts by mass of an 8% aqueous solution is charged and the inside of the reaction vessel is heated to 80 ° C. To this, 28 parts by mass of a 2% aqueous solution of ammonium persulfate is added. After dissolving 4 parts by mass of acrylamide in a mixed solution of 47 parts by mass of methyl methacrylate, 33 parts by mass of butyl acrylate, and 7 parts by mass of acrylic acid, the monomer mixture is allowed to flow into the reaction vessel from the dropping tank over 30 minutes. .. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another 30 minutes after the inflow is completed. Furthermore, to 3485 parts by mass of water, 22 parts by mass of 25% SE-1025N aqueous solution, 38% by mass
Dissolve 7 parts by mass of JS-2 aqueous solution, 841 parts by mass of N-isopropylacrylamide, 53 parts by mass of 2-hydroxyethyl methacrylate, 4 parts by mass of acrylic acid, 11 parts by mass of methylenebisacrylamide, and 44 parts by mass of 2% ammonium persulfate aqueous solution. The thus-prepared aqueous solution is allowed to flow into the reaction vessel from the dropping tank for 3 hours. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another hour after the inflow is completed. Thus, a polymer (3) having a resin solid content of 18.3% and a temperature response of pH 4.4 was obtained.

[0066]

[Production Example 8] (Polymer (4) exhibiting temperature responsiveness) 1,000 parts by mass of water and "SE-1025N" were placed in a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer.
(Asahi Denka Kogyo Co., Ltd. reactive emulsifier) 25% aqueous solution 13
Mass parts and 28 mass parts of 38% aqueous solution of "JS-2" (reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) are charged, and the inside of the reaction vessel is kept at 80 ° C. Add 2% ammonium persulfate solution 2
Add 8 parts by weight. After dissolving 4 parts by mass of acrylamide in a mixed solution of 47 parts by mass of methyl methacrylate, 33 parts by mass of n-butyl acrylate, and 7 parts by mass of acrylic acid, this monomer mixed solution was put into a reaction vessel from a dropping tank over 30 minutes. Inflow. Keep the temperature in the reaction vessel at 83 ° C during the inflow,
Hold for another 30 minutes after the inflow ends. In addition, water 34
To 85 parts by mass, 25% of "SE-1025N" aqueous solution 22
Parts by mass, 38% "JS-2" aqueous solution 7 parts by mass, N-isopropylacrylamide 851 parts by mass, methacrylic acid 2
-53 parts by mass of hydroxyethyl, 4 parts by mass of acrylic acid,
An aqueous solution in which 1 part by mass of methylenebisacrylamide and 44 parts by mass of a 2% ammonium persulfate aqueous solution were dissolved,
Flow from the dropping tank into the reaction vessel for 3 hours. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another hour after the inflow is completed. Thus, the resin solids content of 18.3
%, And a polymer (4) exhibiting a temperature response of pH 4.4 was obtained.

[0067]

[Production Example 9] (Polymer (5) exhibiting temperature responsiveness) 1,000 parts by mass of water and "SE-1025N" were placed in a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer.
(Asahi Denka Kogyo Co., Ltd. reactive emulsifier) 25% aqueous solution 27
Mass parts and 56 mass parts of a 38% aqueous solution of "JS-2" (reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) are charged, and the inside of the reaction vessel is heated to 80 ° C. Add 2% ammonium persulfate solution 2
Add 8 parts by weight. After dissolving 4 parts by mass of acrylamide in a mixed solution of 47 parts by mass of methyl methacrylate, 33 parts by mass of butyl acrylate, and 7 parts by mass of acrylic acid, the monomer mixture is allowed to flow into the reaction vessel from the dropping tank over 30 minutes. .. The temperature in the reaction vessel is maintained at 83 ° C. during the inflow, and is maintained for another 30 minutes after the inflow is completed. In addition, water 3485
22 parts by weight of 25% “SE-1025N” aqueous solution, 7 parts by weight of 38% “JS-2” aqueous solution, 855 parts by weight of N-isopropylacrylamide, 53 parts by weight of 2-hydroxyethyl methacrylate, and 1 part of methylenebisacrylamide. 3 parts by weight of an aqueous solution prepared by dissolving 44 parts by weight of a 2% ammonium persulfate aqueous solution into the reaction vessel from the dropping tank.
Inflow over time. The temperature in the reaction vessel is kept at 8 during the inflow.
Keep at 3 ° C and hold for another hour after the inflow is complete. Thus, a polymer (5) having a resin solid content of 18.3% and a temperature response of pH 4.4 was obtained.

[0068]

[Reference Example 3] (Acrylic resin A) Stirrer, reflux condenser,
Into a reaction vessel equipped with a dropping tank and a thermometer, 572 parts by weight of water and 3 parts by weight of 38% aqueous solution of "Eleminol JS-2" (reactive emulsifier manufactured by Sanyo Kasei Co., Ltd.) were charged, and the inside of the reaction vessel was heated to 80 ° C. And 2% ammonium persulfate aqueous solution 1
Add 5 parts by weight. 114 parts by mass of methyl methacrylate,
67 parts by mass of n-butyl acrylate, 9 parts by mass of 2-hydroxyethyl methacrylate and 10 parts by mass of acrylic acid, 116 parts by mass of water, "Em920" (Kao Co., Ltd. reactive emulsifier) 20% 12 parts by weight of aqueous solution, 3
A mixture of 3 parts by mass of 8% "JS-2" aqueous solution and 10 parts by mass of 2% aqueous ammonium persulfate solution is used as a pre-emulsion liquid by a homogenizer and allowed to flow into the reaction vessel from the dropping tank for 2 hours. During the inflow, the temperature in the reaction vessel was 83 ° C
Keep on. After the inflow was completed, it was kept for 45 minutes, and subsequently, 486 parts by mass of methyl methacrylate, 267 parts by mass of butyl acrylate, and 2-hydroxyethyl methacrylate 3 were used.
A monomer mixture of 7 parts by mass and 10 parts by mass of acrylic acid, 361 parts by mass of water, 11 parts by mass of a 38% "JS-2" aqueous solution, and 2% ammonium persulfate were used as a pre-emulsion liquid with a homogenizer, and then added from a dropping tank. 2.5 into the reaction vessel
Inflow over time. The temperature in the reaction vessel is kept at 8 during the inflow.
Hold at 3 ° C and hold for an additional 1.5 hours after the inflow is complete.
Cool to room temperature, resin solids 45.0%, pH 2.
An acrylic resin A having a number average molecular weight of 53,000 was obtained.

[0069]

Reference Example 4 (Clear powder paint) 63 parts by mass of xylene was charged into a reaction vessel equipped with a thermometer, a stirrer, a cooling tube, a nitrogen introducing tube, and a dropping funnel, and heated to 130 ° C. Using a dropping funnel in this container, 45 parts by mass of glycidyl methacrylate, 20 parts by mass of styrene, 27 parts by mass of methyl methacrylate, 8 parts by mass of isobutyl methacrylate, 6.5 parts by mass of t-butyl peroctoate and xylene. 6 parts by mass of the mixed solution was added dropwise at a constant rate over 3 hours. After completion of dropping, t-butyl peroctoate 0.1
Parts by mass and 7 parts by mass of xylene were added dropwise at a constant rate in 30 minutes using a dropping funnel. After the dropping was completed, the temperature was further maintained at 130 ° C. for 1 hour, and then xylene was distilled off under reduced pressure to obtain an acrylic resin B. 100 parts by mass of this acrylic resin B, 27.3 parts by mass of decanedicarboxylic acid, 1.27 parts by mass of 2,6-di-t-butyl-4-methylphenol, tris (4-t-butylphenyl) phosphite 2 0.54 parts by mass, surface conditioner 0.
After mixing 76 parts by mass and 0.64 parts by mass of benzoin, the resulting mixture was melt-kneaded using a Buscon Kneader, extruded, and cooled to obtain a solid coating composition. Ultracentrifugal pulverization using an "ultracentrifugal pulverizer" manufactured by Mitamura Riken Kogyo Co., Ltd., classification (150 mesh), and further classification 10
0.2 parts by mass of Aerosil R-974 manufactured by Nippon Aerosil Co., Ltd. is added to 0 parts by mass and well mixed to obtain an average particle size of 2
A powder coating composition of 5 μm was obtained.

[0070]

[Reference Example 5] (High-solid type clear paint) 30 parts by weight of styrene, 40 parts by weight of n-butyl methacrylate, 10 parts by weight of 2-ethylhexyl acrylate in an organic solvent of 80 parts by weight of xylol and 20 parts by weight of n-butanol. -Hydroxyethyl acrylate 18 parts by mass and 2 parts by mass of acrylic acid were reacted to obtain an acrylic resin solution having a number average molecular weight of 4,500 and a resin solid content of 50%. To 150 parts by mass of this acrylic resin solution, 25 parts by mass of “Cymel 235” and 0.5 parts by mass of dodecylbenzenesulfonic acid were added to obtain a high solid type clear paint having a solid content of 55%.

[0071]

Reference Example 6 (Preparation of Pigment Paste for Intermediate Coating / White Base Coating) To 100 parts by mass of the nonvolatile content of acrylic resin A, a pigment was added in the composition shown in Table 1. Glass beads were further added to this, and a high share was applied with a paint conditioner. The glass beads were filtered and removed to obtain a pigment dispersion paste.

[0072]

[Table 1]

[0073]

Reference Example 7 (Preparation of Pigment Paste for Silver Metallic Paint) To 100 parts by mass of the non-volatile content of acrylic resin A, an aluminum pigment paste having the composition shown in Table 2 was added.
This was thoroughly stirred with a lab disper to obtain a pigment dispersion paste.

[0074]

[Table 2]

[0075]

[Examples 1 to 5 (temperature-sensitive resin composition), Comparative Examples 1 to 9]
According to Table 3, a pigment paste, an aqueous composition or a composite of an aqueous composition and an emulsion polymer, a polymer exhibiting temperature response, an amino resin, and an acrylic resin A are mixed, and 25
% Aqueous solution of dimethylaminoethanol and water to adjust pH and solid content to obtain temperature-sensitive resin compositions of Examples 1-5.
Further, according to Tables 4 and 5, a pigment paste, an aqueous composition or a composite of an aqueous composition and an emulsion polymerization composition, a polymer exhibiting temperature response, an amino resin, and an acrylic resin A.
Were mixed, and the pH and solid content were adjusted with a 25% dimethylaminoethanol aqueous solution and water to obtain resin compositions of Comparative Examples 1 to 9. Subsequently, the temperature-sensitive resin compositions of Examples 1 to 5 and the resin compositions of Comparative Examples 1 to 9 were subjected to sagging evaluation of coating films, smoothness test, gloss, and water resistance test, as shown below. .

A resin composition coating solution prepared in Examples 1 to 5 or Comparative Examples 1 to 9 was applied to each of the commercially available electrodeposited test plate, degreased mild steel plate, and ABS plate whose surface was washed with methanol. Was air-spray coated so that the thickness of the dried coating film was 20 μm. The coating was performed in a booth adjusted to 25 ° C. and a humidity of 65% by heating the coating liquid to 40 ° C. After setting for about 7 minutes (during which sagging evaluation was performed), this was heated and dried at 50 ° C. for 5 minutes. Subsequently, it was baked at 150 ° C. for 25 minutes to obtain a test coated plate, and the smoothness, gloss, and water resistance of the coated surface were tested. 1) Sagging was visually evaluated as follows. ○: No sag △: Slight sagging ×: Clear sagging 2) Use a surface roughness meter (Surfcom, trade name, manufactured by Toyo Seimitsu Co., Ltd.) for smoothness Center line average roughness Ra (μm) was measured.

3) For the gloss, a specular reflectance of 60 ° -60 ° was measured using a gloss meter GM-268 (manufactured by Minolta Co., Ltd.). 4) For water resistance, the coated plate was immersed in warm water at 80 ° C for 24 hours, then allowed to stand at 20 ° C and humidity of 65% for 24 hours, and then subjected to a tape peeling test (1 x 1 mm 100 pieces) to remove the coating film. Was evaluated as follows. As the tape, Sellotape (registered trademark) having a width of 18 mm (manufactured by Nichiban Co., Ltd.) was used. ◯: 100/100 (no peeling) Δ: 99/100 to 70/100 ×: 69/100 or less The results of Examples 1 to 5 are shown in Table 3 and the results of Comparative Examples 1 to 9 are shown in Tables 4 and 5. It was

[0078]

[Table 3]

[0079]

[Table 4]

[0080]

[Table 5]

[0081]

Examples 6 to 8 and Comparative Examples 10 to 15 (Coating film formation and test method) A commercially available test plate coated with an electrodeposition coating film had a dry coating film thickness of 40 µm according to Tables 6 and 7. It was air spray painted so that For coating, heat the coating liquid to 40 ° C and
It was carried out in a booth adjusted to 5 ° C. and a humidity of 65%.
Form an intermediate coating film by setting for about 7 minutes,
Preheated at 80 ° C. for 5 minutes. Wet it on
A wet aqueous white base paint or metallic base paint was air-spray coated so that the film thickness after drying was 40 μm, and the setting was performed for about 7 minutes. This was preheated again at 80 ° C. for 5 minutes. Then, a clear powder coating or a high solid type clear coating was applied electrostatically by wet-on-wet to a film thickness of 60 μm and baked at 150 ° C. for 25 minutes to obtain a test coated plate, and the following evaluations were carried out. . The evaluation results are shown in Tables 6 and 7.

Smoothness: Center line average roughness Ra (μ
m) was measured. Gloss: 60 degree-60 degree specular reflectance was measured. Water resistance: Evaluation of coated surface after immersion at 40 ° C. for 10 days. ○: No abnormalities are observed. △: Some blistering was observed. ×: Swelling occurred remarkably.

[0083]

[Table 6]

[0084]

[Table 7]

[0085]

Examples 9 to 11 and Comparative Examples 16 to 21 (Coating film formation and test method) A commercially available test plate coated with an electrodeposition coating film had a dry coating film thickness of 20 μm according to Tables 8 and 9. It was air spray painted so that The coating was performed in a booth adjusted to 25 ° C. and a humidity of 65% by heating the coating liquid to 40 ° C. An intermediate coating film was formed by setting for about 7 minutes and preheated at 50 ° C. for 5 minutes. Wet this
An aqueous white base paint or a metallic base paint was applied by on-wet air spray coating so that the film thickness after drying was 20 μm, and set for about 7 minutes. This was preheated again at 50 ° C. for 5 minutes. Then, a clear powder coating or a high solid type clear coating was applied electrostatically by wet-on-wet to a film thickness of 60 μm and baked at 150 ° C. for 25 minutes to obtain a test coated plate, and the following evaluations were carried out. . The evaluation results are shown in Table 8 and Table 9.
It was shown to.

Smoothness: Center line average roughness Ra (μ
m) was measured. Gloss: 60 degree-60 degree specular reflectance was measured. Water resistance: Evaluation of coated surface after immersion at 40 ° C. for 10 days. ○: No abnormalities are observed. △: Some blistering was observed. ×: Swelling occurred remarkably.

[0087]

[Table 8]

[0088]

[Table 9]

[0089]

EFFECTS OF THE INVENTION The present invention provides a temperature-sensitive resin composition which suppresses sagging at the time of coating and has excellent smoothness, gloss and water resistance of a coating film of a solvent type paint.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09D 133/26 C09D 133/26 201/00 201/00 F term (reference) 4J002 AA011 BG041 BG051 BG132 4J011 AA05 KA10 KA15 KA21 KB01 KB22 4J015 CA04 CA06 CA07 CA08 CA09 4J038 CA021 CB021 CB171 CC021 CD021 CD081 CF031 CG141 CG172 DL031 KA03 KA09 MA08 MA10 NA01 NA04 PB05 PB07 PC02 PC04 PC08

Claims (6)

[Claims] 1. An aqueous composition produced by using an oil-soluble initiator and an oil-soluble reducing agent in an aqueous medium, and a polymer exhibiting temperature responsiveness having a lower critical solution temperature. A temperature-sensitive resin composition characterized by: 2. The temperature-sensitive resin composition according to claim 1, wherein the aqueous composition is produced by further using a water-soluble initiator. 3. The temperature-sensitive resin composition according to claim 1, wherein the aqueous composition is produced by further using a reactive emulsifier. 4. The temperature-sensitive resin composition according to claim 1, further comprising an emulsion polymerization composition. 5. The monomer constituting the temperature-responsive polymer having a lower critical solution temperature contains at least one N-substituted (meth) acrylamide derivative.
The temperature-sensitive resin composition according to any one of 4 above. 6. The temperature-sensitive resin composition according to any one of claims 1 to 5, wherein the temperature-sensitive resin composition is used for an intermediate coat paint or a top coat base paint for automobiles.