JP2003082280A - Resin composition for colored coating material and method for applying laminated coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for a colored coating excellent in metal-orienting property, capable of coating with a high non-volatile content and excellent in performances of the conventional coating material such as chipping, etc., and a method for applying a laminated coating. SOLUTION: This resin composition for the colored coating material containing (A) a polyester resin having hydroxy group, (B) a curing agent, (C) inner cross-linking type fine particles, and (D) a urea-based rheology- controlling agent. The method for finishing the laminated coating is to apply a base coating material consisting of the resin composition for the colored coating material on a base substrate, and then apply a top clear coating material on the base coating to form a cured coating film, and the method for finishing the laminated coating is to apply a middle coating material consisting of the resin composition for the colored coating material, applying a base coating material on the middle coating material and then the top clear coating material on the base coating material to form the cured film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin for a colored coating which is excellent in the orientation of the pigment, has a good finished appearance, and is capable of reducing the coating volatile content and preventing the peeling of the coating film called chipping or peeling. The present invention relates to a composition and a laminated coating method using the composition.

[0002]

2. Description of the Related Art A metal material is coated with an electrodeposition primer and an intermediate coating material, and a base coating material and a top clear coating material (hereinafter referred to as "top clear coating material") containing a pigment.
Top clear. The coating method of laminating the top coating composition consisting of (1) has reached the majority of automobile coating systems.

In this laminated coating film, the electrodeposition primer coating film has the main purpose of anticorrosion function of the metal material,
Further, the intermediate coating film smoothes the top coating film, and also has an action as a base for obtaining a coating film with good gloss, and the electrodeposition primer coating film and the top coating film having different functions for a long period of time. It has the effect of bringing them into close contact.

Further, the base coating film includes a solid color base coating film containing an inorganic and / or organic pigment and a metallic base coating film containing a metallic powder such as aluminum or bronze, and these give a beautiful appearance / design by coloring. The purpose is to do. Also, the top clear coating film is glossy,
The purpose is to impart a glossy appearance and long-term weather resistance to the coating film.

Further, in recent years, from the viewpoint of cost reduction, a laminated coating has been adopted in which the intermediate coating step is omitted, two layers of base coating are coated on the electrodeposition primer coating, and top clear is coated thereon. ing.

In such an overcoat coating film, the base coating material and the top clear coating material are applied by the wet-on-wet method and baked at the same time from the viewpoint of shortening the process and saving energy. A so-called 2 coat 1 bake system, 3 coat 1 bake system, which is a laminated coating method, is used.

While the two-coat one-bake system or the three-coat one-bake system has many advantages, it has many problems. As the base paint, a resin system in which an acrylic resin is used as an essential base component and an amino resin is used as an essential curing agent component and these components are combined is usually used.

[0008] However, in such a coating, the orientation of aluminum, which is a commonly used brightening agent (hereinafter referred to as metal orientation), is not sufficient, and the coating non-volatile content is not high.

Although the addition of a rheology control agent has been proposed in order to improve the metal orientation, a sufficient improvement effect has not been obtained.

Further, in recent years, due to increasing environmental problems, regulations on the discharge of organic solvents have become stricter, and particularly for base paints that discharge a large amount of solvent, development and study of paints with a small solvent content are actively conducted. It is being appreciated. As one example, a low molecular weight acrylic resin has been devised and used in part as a means for lowering the resin viscosity in the coating material in order to increase the coating non-volatile content. However, with the decrease in the molecular weight of the acrylic resin, the metal orientation decreases, and further coating peeling (chipping or peeling) at the interface of the intermediate coating film or electrodeposition coating film due to pebbles hitting during running, etc. The deterioration of coating film physical properties is a problem.

In order to solve the above-mentioned problems of metal orientation and film peeling, a system in which a polyester resin is blended with a resin component of acrylic resin / amino resin has been proposed, but a sufficient improvement effect can be obtained. Not not.

[0012] Therefore, the problem to be solved by the present invention is to provide a resin composition for a colored coating which is excellent in metal orientation, can be coated with a high non-volatile content, and is also excellent in the performance such as chipping or peeling which the conventional coating has. And a laminated coating method using the same.

[0013]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present inventors have diligently studied improvement of metal orientation of a resin composition for colored coating and high solidification. As a result, the specific polyester resin (A) and curing agent (B)
A resin composition for a colored coating material, which contains an internal cross-linking type fine particle (C) and a urea rheology control agent (D), has excellent metal orientation, is capable of high solid differentiation, and is a base formed using the same. It has been found that a coating material or an intermediate coating material has excellent coating performance such as chipping or peeling, and the present invention has been completed.

That is, the present invention is characterized by containing a polyester resin (A) having a hydroxyl group, a curing agent (B), internal cross-linking type fine particles (C) and a urea rheology control agent (D). A resin composition for use is provided.

Further, according to the present invention, a base coating material comprising the resin composition for colored coating material is applied onto a base material, and then a top clear coating material is applied onto the base coating material to form a cured coating film. The present invention provides a laminated coating finishing method characterized by the above.

In the present invention, an intermediate coating composition comprising the above resin composition for colored coating composition is applied on a substrate, a base coating composition is applied on the intermediate coating composition, and the base coating composition is further applied. In addition, the present invention provides a laminated coating finishing method which comprises applying a top clear coating to form a cured coating film.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The specific constitution of the present invention and its function and effect will be described below. The resin composition for colored coating material of the present invention comprises a polyester resin (A) having a hydroxyl group,
It contains a curing agent (B), internally crosslinked fine particles (C), and a urea rheology control agent (D).

If the polyester resin has a hydroxyl group, a coating film having good metal orientation can be obtained, high solidification is relatively easy, curability is good, crosslinking density is sufficient and hardness is a coating film. A coating film with excellent performance, which does not cause cissing or decrease in gloss, can be obtained. Above all,
Obtained by reacting a polyhydric alcohol with a polybasic acid of which 60 mol% or more is an alicyclic polybasic acid, and has a weight average molecular weight of 800 to 30,000 and a solid hydroxyl value of 10 to 200.
mgKOH / g, acid value of solid content is 1 to 50 mgKOH / g
The above polyester resin is preferable because the above effect is more remarkable.

Polyester resin (A) having a hydroxyl group
Can be produced by a conventionally known method such as an esterification reaction or a transesterification reaction using a polybasic acid and a polyhydric alcohol. Of these, 60 as the polybasic acid component
Those in which mol% or more is an alicyclic polybasic acid are preferable.

Examples of the polybasic acid include (anhydrous) phthalic acid, isophthalic acid, terephthalic acid, p-tert-butylbenzoic acid, (anhydrous) trimellitic acid, and tetrachloro (anhydrous).
Various aromatic acids such as phthalic acid; adipic acid, azelaic acid, sebacic acid, (anhydrous) maleic acid, fumaric acid,
Itaconic acid or the like can be used. Note that, for example, (anhydrous) phthalic acid means both phthalic anhydride and phthalic acid.

Examples of the alicyclic polybasic acid include 1,1-
Cyclohexanedicarboxylic acid, hexahydro (anhydrous) phthalic acid, 1,3-cyclohexanedicarboxylic acid, 1,4
-Cyclohexanedicarboxylic acid, tetrahydro (anhydrous)
Various alicyclic rings such as phthalic acid, methylhexahydro (anhydrous) phthalic acid, (anhydrous) hettic acid, (anhydrous) hymic acid [registered trademark of Hitachi Chemical Co., Ltd.], hydrogenated (anhydrous) trimellitic acid Formula carboxylic acids are mentioned. Furthermore, if necessary, various alicyclic monocarboxylic acids such as 4-tert-butylcyclohexanemonocarboxylic acid and hexahydrobenzoic acid, or their methyl esters can be used.

As typical examples of polyhydric alcohol components used with these polybasic acid components, ethylene glycol, propylene glycol, 1,
3-butylene glycol, 1,4-butylene glycol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, triethylene glycol, cyclohexanedimethanol, hydrogenated bisphenol A, glycerin, trimethylolethane, trimethylol Examples thereof include propane, pentaerythritol, dipentaerythritol, sorbitol and the like.

In preparing the polyester resin (A) having the hydroxyl group, an oil component can also be used as a part of the component. Particularly representative examples of these oil components include coconut oil, hydrogenated coconut oil, soybean oil, castor oil, dehydrated castor oil, etc., and octenoic acid, isononanoic acid, rice bran oil fatty acid, tall oil fatty acid. Fatty acids such as, and epoxy compounds such as "Curular E" (manufactured by Shell Co.) can be appropriately used.

Either a linear structure or a branched structure may be used as the hydroxyl group-containing polyester resin (A) using each of the above raw material components. Further, the method for preparing the polyester resin (A) having the hydroxyl group is not particularly limited, but a well-known manufacturing method by esterification reaction of an acid component and an alcohol component is used, and either the melting method or the solvent method is used. You can obey.

For example, the polybasic acid component and the polyhydric alcohol component, which are raw materials, are used so as to have a predetermined molecular weight, hydroxyl value and acid value, and the produced water is sequentially removed at 150 to 250 ° C. in a nitrogen stream. However, the esterification reaction can be carried out, and after the completion of the esterification reaction, the polyester resin (A) having a predetermined acid value and hydroxyl value can be obtained by adding a predetermined amount of solvent.

The polybasic acid and polyhydric alcohol which are the reaction components may be added all at once, or may be added in several batches. In the esterification reaction for preparing the polyester resin (A), if necessary, dibutyltin oxide, antimony trioxide, zinc acetate, manganese acetate, cobalt acetate, calcium acetate, in order to accelerate the reaction, Known catalysts such as lead acetate, tetrabutyl titanate and tetraisopropyl titanate may be used.

Next, the curing agent (B) used in the present invention is not particularly limited as long as it reacts with the hydroxyl group in the polyester resin (A) having the hydroxyl group to form a crosslink, and a typical example. Examples include melamine resins, benzoguanamine resins, urea resins, amino resins represented by thiourea resins, polyisocyanate compounds, polyisocyanate compounds such as blocked isocyanate compounds and trimellitic anhydride, and the like. It is particularly preferable to use an amino resin and / or a blocked isocyanate compound which is a one-pack type and is easy to handle.

Amino resins, particularly melamine resins, include alkyl etherified melamine resins, which are particularly representative. Furthermore, if a typical trade name of the alkyl etherified melamine is given as an example,
Various butylated melamine resins such as "Super Beckamine L-117-60" (manufactured by Dainippon Ink and Chemicals, Inc.) and "Uban 255" (manufactured by Mitsui Chemicals, Inc.); "Cymel 301", "Cymel 303""," Cymel 32
5 "," Cymel 327 "[Mitsui Cytec Co., Ltd.
Methylated melamine resin such as "Watersol S-695" (manufactured by Dainippon Ink and Chemicals, Inc.); "Cymel 235", "Cymel 1130" [Mitsui Cytec Co., Ltd.], "BEETLE BE3020", "BE
"ETLE BE3021", "BEETLE BE37
51 "(all manufactured by BIP Ltd. in the UK), such as methyl-butylated mixed etherified melamine resin.

As the blocked isocyanate compound, various blocked polyisocyanate compounds obtained by blocking various polyisocyanate compounds with various blocking agents and cyclized dimerization of isocyanate groups can be obtained. By heat, like compounds containing various uretdione structures,
There are compounds in which the isocyanate group is regenerated.

Typical names of the products are "Barnock DB-980K" and "Barnock B7-887-".
60 "," Barnock B3-867 "[above, blocked isocyanate resin manufactured by Dainippon Ink and Chemicals, Inc.],
"Coronate 2507" [blocked isocyanate resin manufactured by Nippon Polyurethane Co., Ltd.], "Takenate B-815"
N ”[blocked isocyanate resin manufactured by Takeda Pharmaceutical Co., Ltd.] and the like.

The ratio (A / B) of the polyester resin (A) to the curing agent (B) in the resin solid content is not particularly limited, but the range of 60/40 to 90/10 is the adhesiveness and the like. It is more preferable because a base coating film excellent in various properties and curability can be obtained.

Next, the internally crosslinked fine particles (C) will be described. The internally crosslinked fine particles (C) used in the present invention are
The particles are particles made of a vinyl-based resin having a three-dimensionally crosslinked structure inside the particles, and are fine particles that can exist in a dispersed state in the resin composition for colored coating material of the present invention.

The internally crosslinked fine particles (C) can be produced, for example, by polymerizing vinyl monomers by a known polymerization method for obtaining a dispersion.
For example, a non-aqueous dispersion that is a production method in which the selected vinyl monomer is polymerized in the presence of a dispersion stabilizer in an organic solvent that does not dissolve the formed polymer of various selected vinyl monomers. Manufactured by a polymerization method or a polymerization method such as an emulsion polymerization method in which vinyl monomers are polymerized in the presence of various surfactants, water-soluble resins or dispersion stabilizers such as ionic initiator fragments in an aqueous medium. can do.

At this time, as the method of the internal cross-linking type, for example, the following or the following method can be used. Monomers having at least two (α, β-ethylenic) unsaturated bonds in one molecule, that is, polyfunctional monomers, and one (α, β-ethylenic) in one molecule. ) Non-aqueous dispersion at a temperature of 20 ° C. or more and less than 200 ° C. using an unsaturated bond-containing monomer, that is, a monofunctional monomer and an organic and / or inorganic radical polymerization initiator. Alternatively, a method of polymerizing in the state of an aqueous emulsion. A method in which a monomer having various reactive functional groups is used as the vinyl-based monomer, and the reactive functional groups are reacted to crosslink.

Here, as a typical example of the above-mentioned polyfunctional monomers to be used in the above, ethylene glycol di (meth) acrylate having a total carbon number of 10 is given.
28 oligoethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate,
Triethylene glycol di (meth) acrylate, 1,
3-butylene glycol di (meth) acrylate, 1,
6-hexanediol dimethacrylate, neopentyl glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin tri (meth) acrylate, penta Poly (meth) acrylates of various polyhydric alcohols such as erythritol tetra (meth) acrylate;

Esters of various allyl alcohols such as diallyl succinate, diallyl phthalate and triallyl isocyanurate; butadiene, pentadiene,
Various dienes such as isoprene and chloroprene; or divinylbenzene or dicyclopentenyl (meth) acrylate, among which divinylbenzene, dicyclopentenyl (meth) acrylate, triallyl isocyanurate or polyhydric alcohol It is preferable to use poly (meth) acrylates.

The total content of the polyfunctional monomers used in the above-mentioned internal cross-linking method in the internal cross-linking type fine particles is 0 from the viewpoint of aluminum orientation of the coating material after coating, dispersion stability and the like. 0.01 to 90 mass% is preferable.

As the monofunctional monomers, methyl (meth) acrylate, ethyl (meth) acrylate,
1 carbon atom such as n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate. 22 alkyl alcohols and various alkyl esters of (meth) acrylic acid;

Various aralkyl (meth) acrylates such as benzyl (meth) acrylate and phenethyl (meth) acrylate; Various cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; Methoxy Various alkoxyalkyl (meth) acrylates such as ethyl (meth) acrylate and methoxybutyl (meth) acrylate;

2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3
Various hydroxyalkyl (meth) acrylates such as -hydroxybutyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate; Various hydroxyl group-containing vinyl ethers such as 2-hydroxyethyl vinyl ether and 4-hydroxybutyl vinyl ether; Various hydroxyl group-containing allyl ethers such as 2-hydroxyethyl allyl ether; Various polyether polyols represented by polyethylene glycol And various unsaturated carboxylic acids typified by (meth) acrylic acid and the like, monoesters of various polyoxyalkylene glycols of the class; typified by glycidyl (meth) acrylate And the epoxy group-containing unsaturated monomer,
Various adducts with various acids represented by acetic acid and the like;
Various unsaturated carboxylic acids represented by (meth) acrylic acid, etc., and various monoepoxy compounds other than epoxides of α-olefins represented by "Curular E" (trade name of Shell Co., Netherlands) An adduct of the above-mentioned various hydroxyl group-containing vinyl monomers with γ-butyrolactone, δ-valerolactone, γ-valerolactone,
Various hydroxyl group-containing vinyl monomers having a (poly) lactone chain such as adducts with various lactones represented by γ-caprolactone, ε-caprolactone, γ-nonanoic lactone, δ-dodecanolactone, etc. ;

2-Trimethylsiloxyethyl (meth) acrylate, 2-trimethylsiloxyethyl vinyl ether, 2- (1-ethoxy) ethoxyethyl (meth) acrylate, 2- [2- (meth) acryloyloxy]
Vinyl-based single monomers containing various blocked hydroxyl groups such as ethoxytetrahydrofuran, 3- [2- (meth) acryloyloxy] ethyloxazolidine and 2,2-dimethyl-3- [2- (meth) acryloyloxy] ethyloxazolidine. Quantities;

Various unsaturated carboxylic acids such as (meth) acrylic acid, 2-carboxyethyl (meth) acrylate, crotonic acid, itaconic acid, maleic acid or fumaric acid; monomethyl itaconate, mono-n-butyl itaconate. , Monomethyl maleate, mono-n-butyl maleate, monomethyl fumarate, mono-n-butyl fumarate, various monoesters (half esters);
Monovinyl esters of various saturated dicarboxylic acids such as monovinyl adipate and monovinyl succinate; anhydrides of various unsaturated polycarboxylic acids such as maleic anhydride and itaconic anhydride; acrylic anhydride or methacrylic anhydride Anhydrides of various unsaturated monocarboxylic acids, such as:
Or having a carboxylic acid anhydride group, such as a mixed acid anhydride of various unsaturated carboxylic acids such as acrylic acid or methacrylic acid and various saturated carboxylic acids such as acetic acid, propionic acid, benzoic acid, etc. Vinyl monomers;
Trimethylsilyl (meth) acrylate, dimethyl-t
Vinyl monomers containing a blocked carboxyl group, such as butylsilyl (meth) acrylate, 1-ethoxyethyl (meth) acrylate and 2- (meth) acryloyloxytetrahydrofuran;

Diesters of various unsaturated dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid with monohydric alcohols; vinyl acetate, vinyl propionate, vinyl pivalate, vinyl versatate, vinyl benzoate. , Various kinds of carboxylic acid vinyl esters such as "Beoba" (trade name, vinyl esters manufactured by Shell in the Netherlands); methyl crotonate, ethyl crotonate,
Various alkyl esters of crotonic acid; Various cyano group-containing monomers such as (meth) acrylonitol and crotononitrile;

2-dimethylaminoethyl (meth) acrylate, N- [2- (meth) acryloyloxy] ethylmorpholine, vinylpyridine, N-vinylcarbazole, N- (2-dimethylamino) ethyl (meth) acrylamide, N -(2-Diethylamino) ethyl (meth)
Amino group-containing vinyl monomers such as acrylamide, N- (2-dimethylamino) ethyl crotonic acid amide, N- (2-diethylamino) ethyl crotonic acid amide, 2-dimethylaminoethyl vinyl ether, 2-diethylaminoethyl vinyl ether Kind;

Methyl (meth) acrylamide glycolate methyl ether, methyl (meth) acrylamide glycolate, N-isopropyl (meth) acrylamide,
N-methyl (meth) acrylamide, N-vinylformamide, N, N-dimethyl (meth) acrylamide,
N- (meth) acryloylmorpholine, N- (meth) acryloylpyrrolidine, N-vinylpyrrolidone, ethyl (acrylamido) glycolate or ethyl (acrylamido) glycolate methyl ether, etc.
Methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-propoxymethyl (meth) acrylamide, Nn-butoxymethyl (meth)
Acrylamide, N-i-butoxymethyl (meth) acrylamide, N-phenoxymethyl (meth) acrylamide and Nn-hexyloxymethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide,
N-methoxypropyl (meth) acrylamide, Nn
-Various amide group-containing vinyl monomers represented by N-alkoxyalkyl (meth) acrylamides such as butoxyethyl (meth) acrylamide and Ni-butoxyethyl (meth) acrylamide;

Vinyl having an epoxy group, such as glycidyl (meth) acrylate, methylglycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, vinylcyclohexene oxide, glycidyl vinyl ether, methyl glycidyl vinyl ether and allyl glycidyl ether. -Based monomers; 2,
3-carbonate propyl (meth) acrylate, 2-
Various 5-membered cyclocarbonate group-containing vinyl monomers such as methyl-2,3-carbonate propyl (meth) acrylate and 3,4-carbonate butyl (meth) acrylate; 5- [N- (meth ) Acryloylcarbamoyloxymethyl] -5-ethyl-1,3-dioxan-2-one, 5- [N- {2- (meth) acryloyloxy} ethylcarbamoyloxymethyl] -5-
Various 6-membered cyclocarbonate group-containing vinyl monomers such as ethyl-1,3-dioxan-2-one;

Vinyl monomers having a carbamate group such as methyl N- (meth) acryloylcarbamate and ethyl N- [2- (meth) acryloyloxy] ethylcarbamate;

"Viscoat 8F, 8FM, 3F, 3F
M ”(trade name, fluorine-containing (meth) acrylic monomer manufactured by Osaka Organic Chemical Industry Co., Ltd.), purple orocyclohexyl (meth) acrylate, di-perfluorocyclohexyl fumarate or N-iso-propyl perfluorooctane. Various (per) fluoroalkyl group-containing unsaturated bond-containing monomers such as sulfonamide ethyl (meth) acrylate; vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, chlorotrifluoroethylene,
Various fluoroolefins such as hexafluoropropylene; Various chlorinated olefins such as vinyl chloride and vinylidene chloride;

Ethylene, propylene, isobutylene, 1
Various kinds of α-olefins such as butene and 1-hexene; various kinds of aromatic vinyl monomers such as styrene, α-methylstyrene, p-tert-butylstyrene, O-methylstyrene and p-methylstyrene Kind;

Various sulfonic acid amide group-containing monomers such as p-styrene sulfonamide and N-methyl-p-styrene sulfonamide; 2-hydroxyethyl (meth)
Phosphate ester bond-containing unit amount obtained by condensation reaction of various hydroxyalkyl esters of α, β-ethylenically unsaturated carboxylic acid such as acrylate and 2-hydroxypropyl (meth) acrylate with phosphoric acid or its esters Styrene sulfonic acid, vinyl sulfonic acid, 2-acrylamido-2-methyl-propane sulfonic acid, a sulfonic acid group-containing monomer or an organic amine salt thereof;

Vinyltrimethoxysilane, allyltrimethoxysilane, trimethoxysilylethyl vinyl ether, 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 3- (meth) acryloyloxy Various hydrolyzed silyl group-containing vinyl monomers such as propylmethyldimethoxysilane and 3- (meth) acryloyloxypropylmethyldichlorosilane;

Various alkyl vinyl ethers such as ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether and n-hexyl vinyl ether; various cycloalkyl vinyl ethers such as cyclopentyl vinyl ether, cyclohexyl vinyl ether and methyl cyclohexyl vinyl ether;

Various carbonyl group-containing monomers such as acrolein and methyl vinyl ketone;

"Blenmer PME" [NOF CORPORATION]
Various kinds of polyether-containing monomers such as methacrylic acid methoxy-methoxycarbonyl-methyl ester and acrylic acid acetylamino-methoxycarbonyl-methyl ester.

Next, as typical examples of the reaction of the reactive functional group in the above-mentioned internal cross-linking method, a reaction between a carboxyl group and an epoxy group, a reaction between a hydroxyl group and a carboxylic acid anhydride, Reaction of epoxy group with amino group, hydroxyl group with melamine resin, acetoguanamine resin,
Examples include reaction with an alkyl ether group represented by an alkyl ether group-containing compound such as a benzoguanamine resin and an N-alkoxyalkyl (meth) acrylamide group-containing copolymer, or self-condensation of alkyl ether groups with each other. Internal cross-linking can be achieved by providing a functional group related to the above in the intra-particle polymer.

For example, the internal cross-linking by the reaction of a carboxyl group and an epoxy group may be carried out by a method in which unsaturated carboxylic acids and vinyl monomers having an epoxy group are copolymerized and then cross-linked, or a carboxyl group-containing copolymer. Examples thereof include a method of adding a compound having at least two epoxy groups in one molecule such as ethylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether and glycerin triglycidyl ether to the particles.

Furthermore, the combination of other functional groups controlling internal cross-linking is not particularly limited as long as it is a method of reacting inside the particles.

The total content of the compound having a reactive functional group used in the above-mentioned internal cross-linking method in the internal cross-linking type fine particles is, in view of the aluminum orientation of the coating material after coating, dispersion stability, etc. 0.1 to 70 mass% is preferable.

On the other hand, as the initiator, potassium persulfate,
Various inorganic compounds such as ammonium persulfate or hydrogen peroxide; or acetyl peroxide, propionyl peroxide, isobutyryl peroxide, benzoyl peroxide, tert-butyl peroxyoctoate, tert-butyl hydroperoxide, tert- Butyl cumyl peroxide, tert
Various organic compounds such as -butyl peroxybenzoate, di-tert-butyl peroxide, dicumyl peroxide or cumene hydroperoxide or azobisisobutyronitrile are particularly representative.

In the preparation of such internally crosslinked fine particles (C), various known and commonly used dispersion stabilizers or emulsifiers can be appropriately used.

Further, used in non-aqueous dispersion type polymerization,
Typical examples of the dispersion stabilizer are as follows.

Various unsaturated bond-containing polymers such as polybutadiene and polyisoprene are graft-polymerized in a form obtained by polymerizing one or more of various vinyl monomers. Polymer;

Alternatively, in the above unsaturated bond-containing polymers,
A graft copolymer obtained by copolymerizing vinyl-based monomers and (meth) acrylic acid, and a carboxyl group in the graft copolymer, a glycidyl (meth) acrylate of An unsaturated bond-containing graft copolymer obtained by addition-reacting vinyl monomers having various epoxy groups;

Alkyd resin, polyester resin containing or not containing unsaturated bond;

An alkyl etherified melamine resin in the form of being etherified with a C _{4 to} C ₁₂ alkyl alcohol;

Obtained by addition-reacting the above-mentioned vinyl monomers having an epoxy group with the carboxyl group at the terminal position of the self-condensed polyester of various saturated fatty acids having a hydroxyl group such as 12-hydroxystearic acid. A graft copolymer in a form obtained by polymerizing various monomers with a polyester containing a terminal unsaturated bond;

Alternatively, after the above-mentioned polyester containing terminal unsaturated bond, various vinyl monomers and (meth) acrylic acid are copolymerized, the above-mentioned epoxy group is further added to the carboxyl group. An unsaturated bond-containing graft copolymer in a form obtained by subjecting an vinyl-based monomer having the same to an addition reaction; or

N-butyl (meth) acrylate, i
(meth) acrylic acid esters of various alkyl alcohols having C ₄ or more, such as so-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, or stearyl (meth) acrylate, are essential monovalent compounds. Various (co) polymers in the form of a monomer, and a form obtained by copolymerizing other vinyl monomers, if necessary,

The above-mentioned (meth) acrylic acid esters of various alkyl alcohols having C ₄ or more are used as essential monomers, and such various monomers and (meth) acrylic acid are used, if necessary. Further, it is obtained by adding the above-mentioned vinyl monomer having an epoxy group to the carboxyl group in the copolymer obtained by copolymerizing other vinyl monomer. Unsaturated bond-containing copolymers of the form

Graft copolymers obtained by copolymerizing various unsaturated bond-containing copolymers with one or more kinds of various monomers, and various unsaturated bond-containing copolymers Vinyl-based monomer having an epoxy group as described above with respect to the carboxyl group in the copolymer obtained by copolymerizing the monomers, various monomers and (meth) acrylic acid For example, a graft copolymer in a form obtained by subjecting the body to an addition reaction.

Typical examples of dispersion stabilizers used in emulsion polymerization include alkylbenzene sulfonates, lauryl sulfates, dioctyl sulfosuccinates, polyoxyethylene alkyl phenyl ether sulfates, and other anionic interfaces. Activator,

Cationic surfactants such as octadecylamine acetate, tetrabutylammonium chloride, tetradecyldimethylbenzylammonium chloride and trioctylmethylammonium acetate,

Examples include nonionic surfactants such as polyoxyethylene lauryl ether and polyoxyethylene tridecyl ether.

Further, an alkyd resin, a polyester resin, a vinyl resin containing a hydroxyl group, a carboxyl group, a sulfonic acid group, an amino group, or the like, or a vinyl monomer containing a reactive functional group therein, or the like is used. Those containing an unsaturated bond additionally added can also be used as the dispersion stabilizer.

Thus, the internal cross-linking type fine particles prepared by the aqueous emulsion polymerization are mixed with other components constituting the resin composition for colored coating of the present invention, by evaporation of water or azeotrope, or by polymer ( Particles) are separated in advance in the form of solids by physical or chemical means such as sedimentation or agglomeration, or when such physical or chemical means are applied, they are separated from the various polymers in each paint. It is preferable to directly replace the medium of the target internally crosslinked fine particles with water in the presence of the resins and / or organic solvents and the like by the water and the resins and / or organic solvents and the like.

Urea-based rheology control agent (D)
Can be obtained, for example, by reacting a compound having an isocyanate group with a compound having an amino group in a resin or a solvent.

There is no particular limitation on the resin used in the synthesis in the resin solution, and any resin can be used as long as it can dissolve the starting compound having an isocyanate group and the compound having an amino group. Among them, in particular, acrylic resins and polyester resins are particularly preferable because the solubility of the compound and the compatibility in the resin composition for colored coating of the present invention are good, and the content thereof has the characteristics of the present invention. It is preferably 40% or less of the total solid content of the composition of the present invention, which is a range that does not impair. Examples of the solvent include hydrocarbon solvents such as toluene, xylene, cyclohexane, n-hexane and octane; ester solvents such as ethyl acetate, butyl acetate and ethylene glycol monoethyl ether acetate; acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl. Ketone-based solvents such as amyl ketone and cyclohexanone; amide-based solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone; methanol, ethanol, n-propanol, i
Examples thereof include alcohol solvents such as so-propanol, n-butanol, iso-butanol, sec-butanol, tert-butanol, ethylene glycol monoalkyl ether, and mixtures thereof.

The urea type rheology control agent (D) can be produced, for example, by mixing an amino group-containing compound and a mono- or diisocyanate in a resin solution at room temperature and reacting the mixture. The agent-containing resin (hereinafter, abbreviated as urea-based RC agent-containing resin (D ′)) solution is obtained.

Furthermore, it is possible to use polyamine as the amine during the reaction of the amine with the isocyanate to increase the molecular weight, and after reacting a part of the various polyol resins with the isocyanate compound, the residual isocyanate groups are converted into various amines. It is also possible to produce a urethanized urea by reacting.

Examples of the compound having an isocyanate group include alkyl isocyanates such as methyl isocyanate, ethyl isocyanate, propyl isocyanate, butyl isocyanate and stearyl isocyanate; tertiary butyl isocyanate, secondary alkyl isocyanate; phenyl isocyanate, naphthyl isocyanate, tolyl isocyanate. Aromatic isocyanates such as; monoisocyanates represented by alicyclic isocyanates such as cyclohexyl isocyanate,

Aliphatic diisocyanates such as ethylene diisocyanate and hexamethylene diisocyanate; aromatic diisocyanates such as diphenylmethane-4,4-diisocyanate such as cyclohexane diisocyanate and tolylene diisocyanate, xylylene diisocyanate and naphthylene diisocyanate.

Furthermore, prepolymers having an isocyanate group obtained by addition-reacting the above-mentioned various isocyanates with polyhydric alcohols; cyclizing and trimerizing the above-mentioned various polyisocyanates Prepolymers having an isocyanurate ring obtained by the above; polyisocyanates having a biuret structure obtained by reacting the above-mentioned various polyisocyanurates with water;

Homopolymers of vinyl monomers having various isocyanate groups such as 2-isocyanatoethyl (meth) acrylate, 3-isopropenyl-α, α-dimethylbenzyl isocyanate and (meth) acryloyl isocyanate; An isocyanate group-containing vinyl monomer such as a (meth) acrylic copolymerizable with the monomer,
Isocyanate group-containing acrylic copolymer, vinyl ester copolymer or fluoroolefin copolymer obtained by copolymerization with vinyl ester, vinyl ether, aromatic vinyl or fluoroolefin vinyl monomers Various vinyl-based copolymers such as coalescence can also be used as a raw material for the rheology control agent.

Examples of the compound having an amino group include ethylamine, propylamine, butylamine, pentylamine, methylbutylamine, ethylpropylamine, benzylamine, phenylethylamine, and other monoamines; aminoethanol, aminopropanol, aminobutanol, aminopentanol, Hydroxy monoamines such as aminomethyl propanol,

Ethylene diamine, hexamethylene diamine, 3,3'-dimethyl-4,4'-diaminodicyclohexyl methane, 4,4'-diamino-dicyclohexyl methane, 4,4'-diamino-diphenyl methane,
Xylylenediamine, di-aminomethylbenzene, 3
And polyamines such as aminomethyl-3,5,5-trimethylcyclohexylamine.

Here, the contents of the internally crosslinked fine particles (C) and the urea rheology control agent (D) are as follows.
(C) is 1.0 to 3 with respect to the resin solid content mass (A + B).
00 mass% is preferable and 1-200 mass% is especially preferable. (D) is 0 .. based on the resin solid content mass (A + B).
01 to 20 mass% is preferable, and 0.1 to 10 mass% is particularly preferable. With the addition amounts of (C) and (D) in this range, the base coating material having excellent metal orientation is
Further, it is possible to provide a base coating material having a high coating nonvolatile content.

In the resin composition for colored coating material of the present invention, solvents are usually used together with the polyester resin (A), the curing agent (B), the internally crosslinked fine particles (C) or the rheology control agent (D). Examples of the solvent used here include hydrocarbon solvents such as toluene, xylene, cyclohexane, n-hexane and octane; ester solvents such as ethyl acetate, butyl acetate and ethylene glycol monoethyl ether acetate; acetone, methyl ethyl ketone, Ketone-based solvents such as methyl isobutyl ketone, methyl amyl ketone and cyclohexanone; amide-based solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone; methanol, ethanol, n-propanol, iso-propanol, n-butanol,
iso-butanol, sec-butanol, tert-
Examples of the solvent include alcohol solvents such as butanol and ethylene glycol monoalkyl ether, or a mixture thereof.

Curing catalysts can be used in order to accelerate the curing of the resin composition for a colored coating material of the present invention. As a typical example of such curing catalysts, para-toluenesulfonic acid can be given. , Dodecylbenzenesulfonic acid, dinonylnaphthalenedisulfonic acid, or their amine-blocked products, half-esterified products of tetrachlorophthalic anhydride and monohydric alcohol, acid catalysts of organic acids such as trichloroacetic acid; tetraisopropyl titanate, dibutyltin Various metal-containing compounds such as laurate, dibutyltin acetate, dibutyltin dioctate, and cobalt naphthenate; various phosphorus-containing acidic compounds such as monoalkylphosphoric acid, dialkylphosphoric acid, monoalkylphosphorous acid, and dialkylphosphoric acid.

The amount of the curing catalyst used is not particularly limited, but the polyester resin (A) and the curing agent (B) are used.
0.01 to 20 relative to 100 parts by mass of the total solid content of
It is more preferably within the range of parts by mass.

The resin composition for colored coating of the present invention is
Needless to say, a pigment can be used when used as a base paint or an intermediate paint. For example, aluminum powder, carbon black, titanium oxide, magnesium oxide, zinc oxide, metal oxides such as iron oxide, silicates, strontium chromate, zinc chromate, inorganic pigments such as barium sulfate, phthalocyanine blue, phthalocyanine green, Organic pigments such as perylene, quinacridone, and benzidazolone are listed, and these may be blended alone or in any combination.

The above-mentioned hydroxyl group-containing polyester resin (A), curing agent (B), and internally crosslinked fine particles (C)
The resin composition for a colored coating material of the present invention can be obtained by mixing the urea-based rheology control agent (D) and the urea-based rheology control agent (D) by a known method. In addition to other resins, various known additives such as color separation inhibitors, leveling agents, ultraviolet absorbers, antioxidants, defoamers and plasticizers can be added.

In the coating method of the present invention, a base coating comprising the resin composition for colored coating of the present invention is applied onto a base material to form a coating film, and then a top clear coating composition is applied onto the base coating film. And a method for laminating coating finish, which comprises forming a cured coating film, or after applying an intermediate coating composition comprising the resin composition for colored coating composition of the present invention on a substrate to form a coating film. A laminate characterized by applying a base paint on the intermediate coating film to form a coating film, and then applying a top clear coating composition on the base coating film to form a cured coating film. A painting finishing method can be mentioned.

Using the resin composition for colored coating of the present invention,
In order to form a desired highly effective coating film, for example, a surface treatment is applied, or if necessary, a primer layer (for example, an electrodeposition coating layer) is previously applied to the surface of the substrate to be coated. Then, the intermediate coating composition is applied and crosslinked by a usual method under desired conditions so that the dry film thickness is 10 to 80 μm.

After that, as a top coat, a base paint comprising the composition for colored paint of the present invention was applied to give a dry film thickness of 10
To 50 μm, then top clear coating is applied to it so that the dry film thickness is 20 to 80 μm, and then baking is performed under desired conditions, that is, 2 coat 1 bake (2C1B) coating. The usual method is to paint and cure.

Further, the composition for colored coating material of the present invention is formed on the surface of the substrate to be coated on which a primer layer (eg electrodeposition coating layer) has been surface-treated or if necessary, coated beforehand. After applying the intermediate coating material so that the dry film thickness is 10 to 80 μm, the base coating material is applied thereon to have a dry film thickness of 1 μm.
0 to 50 μm, and then a top clear coating composition is applied thereon to a dry film thickness of 20 to 80 μm, and then baking is performed under desired conditions, that is, 3 coat 1 bake (3C1B) conditions. It is also possible to use a method of coating and curing with. In addition,
The resin composition for colored coating material of the present invention can be used for both the intermediate coating material and the base coating material. Also, when applying the base paint on the base material and then applying the top clear paint on it, the top clear paint may be applied after the base paint forms the coating film, or the base paint forms the coating film. You may apply top clear paint before applying. Furthermore, when applying an intermediate coating, a base coating, or a top clear coating on a substrate, the base coating may be applied either before or after the intermediate coating forms a coating film. May be applied either before or after the base paint forms a coating film.

Generally, as the conditions for the above-mentioned respective cross-linking, it is suitable that the temperature is 110 to 170 ° C. for about 15 to 40 minutes, and the range of 120 ° C. to 160 ° C. for 20 to 30 minutes is preferable.

The top clear paint that can be used in the present invention is not particularly limited as long as it is a baking paint, but preferably an acrylic resin, an alkyd resin,
Polyester resin, fluorine resin, silicone resin,
Examples include synthetic resin-based baking paints containing resin components such as urethane-based resins.

As the curing agent component used at that time,
A known and commonly used curing agent having reactivity with a hydroxyl group such as an amino resin, an isocyanate resin, and a polycarboxylic acid anhydride can be used.

Furthermore, in recent years, acid rain resistant paints have been developed, and in place of the melamine curing system, a reaction system of a carboxyl group and an epoxy group, a reaction system of a carboxyl group and a cyclocarbonate group, or an acid anhydride group and a hydroxyl group. It is also possible to use a clear coating material containing a novel curable resin such as a reaction system with.

Further, from the standpoint of resource saving and environmental problems, it is of course possible to use high solid clear paints or powder clear paints having a reduced organic solvent content.

As the coating method of the above-mentioned intermediate coating material, base coating material and top clear coating material, various publicly known conventional coating methods such as air spray coating, electrostatic spray coating, rotary atomization type electrostatic coating and the like can be used. The method can be adopted.

In the thus obtained colored coating composition and laminated coating method of the present invention, the base material is mainly iron products, stainless steel, aluminum, brass, polystyrene, polyethylene, polypropylene, acrylic resin, polycarbonate resin, ABS resin. And the like are preferably applied.

Thus, the intermediate coating composition or base coating composition obtained by using the resin composition for colored coating composition of the present invention has a high solid content per se, which is about 5% as compared with the case of using the conventional resin for base coating composition. A high-solids base paint having a low coating volatile content of about 40% by mass can be obtained. Not to mention the appearance of a comprehensive paint film obtained by applying top clear to the base paint film obtained using this base paint. The coating peeling prevention property called chipping or peeling is remarkably excellent.

The resin composition for a colored coating material of the present invention can be generally used for a colored coating material, but is extremely highly practical especially for a base coating material for automobiles.

[0105]

EXAMPLES The present invention will be described in more detail with reference to Reference Examples, Examples and Comparative Examples. In the following, all parts and% are based on mass unless otherwise specified.

Reference Examples 1 to 6 (Preparation of Polyester Resin) In a 3 liter four-necked flask equipped with a stirrer, a thermometer, a reflux condenser with a dehydration trap, and a nitrogen gas inlet tube, the raw materials shown in Table 1 and dibutyl were added. 0.5 part of tin oxide was charged and the temperature was raised to 220 ° C. Further, a dehydration condensation reaction was carried out at this temperature and continued until the hydroxyl value of the solid content reached the respective target values. After completion of the reaction, the reaction mixture was cooled and xylene was added to obtain a polyester resin solution having a nonvolatile content of 65%. The physical property values are summarized in Table 1.
It was shown to.

[0107]

[Table 1]

The abbreviations in Table 1 mean the following compounds. HHPA: hexahydrophthalic anhydride THPA: tetrahydrophthalic anhydride NPG: neopentyl glycol TMP: trimethylolpropane 1,6-HD: 1,6-hexanediol

Reference Example 7 (Preparation Example of Non-Aqueous Dispersion Type Internally Cross-Linked Fine Particles) “LAWS” (Low aromatics manufactured by Shell Co., Ltd.) 550 parts of hydrocarbon type solvent), 120 of xylene
And 60 parts of n-butanol are charged and the temperature is raised to 80 ° C.

Then, here, "Super Beckamine
13-548 "(Butyl etherified melamine manufactured by Dainippon Ink and Chemicals, Inc .; nonvolatile content 60%), 666 parts,
120 parts of styrene, 264 of methyl methacrylate
Parts, 210 parts of 2-hydroxyethyl methacrylate and 6 parts of ethylene glycol dimethacrylate and te
25 parts of rt-butylperoxy-2-ethylhexanoate were added dropwise over 4 hours.

After the dropping was completed, the reaction was continued at this temperature for 10 hours to obtain a desired non-aqueous dispersion of internally crosslinked fine particles. The non-volatile content of the non-aqueous dispersion thus obtained was 50.2%. Hereinafter, this is abbreviated as internal crosslinked fine particles (C-1).

Reference Example 8 (Preparation example of emulsion type internally crosslinked fine particles) Pure water was charged into a reaction vessel under a nitrogen atmosphere and the temperature was raised to 80 ° C. Next, 1/10 of the mixture (a) and 1/5 of the mixture (b) were added according to the raw material composition as shown in Table 2, and 30 minutes after that, 9/1 of the mixture (a) was added.
0 and 3/5 of the mixture (b) were added dropwise over 3 hours.

After completion of the dropping, 1/5 of the mixture (B) was added and the mixture was maintained at 80 ° C. for 1 hour while stirring to terminate the reaction. The emulsion was filtered with a 200-mesh filter cloth. , NV of 20% and particle size of 0.1 μm internally crosslinked fine particle emulsion (Ce-
2) was obtained.

Further, this emulsion was spray-dried to obtain a microgel powder having a nonvolatile content of 98%. Hereinafter, this is abbreviated as internal crosslinked fine particles (C-2).

[0115]

[Table 2]

<< Footnotes in Table 2 >> All the compositions prepared are parts by mass.

"Hitenol N-08" ... Ammonium polyoxyethylene dodecyl phenyl ether sulfate ester manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.

Reference Example 9 (Preparation of Urea RC Agent) A polyester resin (A-1) was charged in a flask equipped with a thermometer, a reflux condenser, a stirrer, a nitrogen introducing tube and a dropping funnel.
A urea RC agent having a nonvolatile content of 65% was prepared by charging 446 parts, 32 parts of xylene, and 36.1 parts of 1-phenylethylamine, and then adding 23.9 parts of hexamethylene diisocyanate with stirring at room temperature. The containing resin (D'-1) was obtained.

Reference Example 10 (Preparation of Urea RC Agent) 550 parts of xylene and 168 parts of n-butyl acetate were charged into a reaction vessel equipped with a stirrer, a thermometer, a cooler, a nitrogen introducing tube and a dropping funnel, and the mixture was fed to 125 Raise the temperature to ℃.

Here, 380 parts of styrene, 360 parts of n-butyl methacrylate, 200 parts of 2-hydroxyethyl methacrylate, 20 parts of acrylic acid, tert.
-Butylperoxy-2-ethylhexanoate 50
Parts, 15 parts of 2.2'azobis (2-methylbutyronitrile) and 100 parts of xylene are added dropwise over 6 hours, and the reaction is allowed to continue for 5 hours at this temperature even after the completion of the addition.

Next, after cooling to room temperature, 22.1 parts of benzylamine was added, and then 17.9 parts of tolylene diisocyanate was added with stirring to give a resin containing a urea RC agent having a nonvolatile content of 55%. (D'-2)
Got

Examples 1 to 14 and Comparative Examples 1 to 6 Preparation of base paint

The Ford cup N was mixed according to the composition ratio shown in Tables 3 to 7 and diluted with a solvent for dilution.
o. The viscosity according to No. 4 was adjusted to 13 seconds to obtain a base paint.

Preparation of Diluting Solvent Xylene 15 parts "Solvesso 100" 15 copies 40 parts of toluene N-Butyl acetate 10 parts 20 parts of ethyl acetate

[0125]

[Table 3]

[0126]

[Table 4]

[0127]

[Table 5]

[0128]

[Table 6]

[0129]

[Table 7]

"A-322" ... "Acridic A-
322 ”, which is a Dainippon Ink and Chemicals, Inc.
Made acrylic resin (solution type); nonvolatile content = 50% "L-117-60" ... "Super Beckamine L-1
17-60 ", an n-butylated melamine resin manufactured by the same company; non-volatile content = 60%" DB-980K "..." Barnock DB-980K "
And a blocked isocyanate produced by the same company;
Nonvolatile matter = 75% Abbreviation of "7160N" ... "Alpaste 7160N", aluminum paste manufactured by Toyo Aluminum Industry Co., Ltd .; Nonvolatile matter = 65% Abbreviation of "CR-93" ... "Taipec CR-93" And the trade name of the titanium oxide pigment manufactured by Ishihara Sangyo Co., Ltd.

(Preparation of top clear coating composition) Ford cup No. 1 was prepared by mixing a formulation prepared by mixing the following composition with xylene / 1-butanol at a mass ratio of 8/2. The desired clear coat paint was obtained by adjusting the viscosity of No. 4 to 22 to 24 seconds. Acridic A-345 127 parts [Acrylic resin manufactured by Dainippon Ink and Chemicals, Inc.] Super Beckamine L-117-60 50 parts [Melamine resin manufactured by Dainippon Ink and Chemicals, Inc.] Tinuvin 900 3 parts ( UV absorber manufactured by Ciba Geigy) Tinuvin 765 1 part (Radical scavenger manufactured by Ciba Geigy) KP-321 0.05 part [Shin-Etsu Chemical Co., Ltd. leveling agent]

<Evaluation Judgment Procedure>

<2C1B Coating Method> (Examples 1 to 13 and Comparative Examples 1 to 4) A coated plate obtained by coating an automobile electrodeposition primer and an intermediate coating surfacer on a mild steel sheet subjected to phosphoric acid conversion treatment The base paints of Examples 1 to 13 and Comparative Examples 1 to 4 were applied by air spraying so that the dry coating film had a thickness of 17 μm (μm), and then set for 3 minutes.
Then, apply the above-mentioned top clear paint to a dry coating film of 3
It was painted so as to have a thickness of 0 μm.

After leaving it at room temperature for 10 minutes,
It was placed in an electric hot air dryer in an atmosphere of 140 ° C. for 25 minutes to be cured.

<3C1B Coating Method> (Example 14, Comparative Examples 5 to 6) Example 14 and Comparative Example were applied to a coated plate obtained by applying an automobile electrodeposition primer on a mild steel sheet that had been subjected to phosphoric acid conversion treatment. The base paints of Examples 5 and 6 were applied by air spraying so that the dry coating film had a thickness of 25 microns (μm), and then set for 3 minutes. Then, the base coating material of Example 1 was applied by air spraying so that the dry film thickness was 17 microns (μm), and set for 3 minutes. Further, the above-mentioned top clear coating composition was applied onto the base coating film so that the dry coating film had a thickness of 30 μm.

After leaving it at room temperature for 10 minutes,
It was placed in an electric hot air dryer in an atmosphere of 140 ° C. for 25 minutes to be cured.

With respect to the respective coating films thus obtained, various performances were compared and examined. The results are collectively shown in Tables 8-12.

[Outline of Evaluation of Coating Performance]

Finished Appearance (Glossiness etc.) ……………… It is an index showing the sharpness of the coating film evaluated by the image brightness measuring instrument manufactured by Suga Test Instruments Co., Ltd. The larger this value is , Which means that the clarity is good.

Finished appearance (metal orientation, etc.) ... The metallic appearance measuring device "ALCOPE LMR-100" [manufactured by Kansai Paint Co., Ltd.] is used to display the IV value. The higher the evaluation value, the higher the silver color. This means that the finished appearance of the coating film is good.

Finished appearance (metal orientation, etc.): Visual evaluation of coating unevenness of cured coating ◎: No unevenness, good glossiness: No unevenness, △: There is unevenness but no glossiness, ×: Glossiness

Chipping resistance: A stepping stone tester "JA-400" (manufactured by Suga Test Instruments Co., Ltd.) was used, and 50 g of crushed stone No. 7 was used for each condition. Also, the pressure was set to 4 kg / cm ² , and the peeled coating film was visually evaluated. ○: good, △: bad, ×: extremely bad

[0143]

[Table 8]

[0144]

[Table 9]

[0145]

[Table 10]

[0146]

[Table 11]

[0147]

[Table 12]

As described above, the resin composition for a colored coating material and the laminated coating method according to the present invention have a high non-volatile content at the time of coating and, moreover, especially in metal orientation and chipping resistance. It is excellent and extremely practical.

[0149]

The resin composition for colored coating material of the present invention forms a coating film having a high solid content and excellent in various properties such as gloss, curability and chipping resistance. By using the resin composition for intermediate coating or base coating, it is possible to perform coating excellent in various properties such as gloss, curability and chipping resistance.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koma ▲ Saki ▼ Shigeru             3-2-7-501 Ibukino, Izumi City, Osaka Prefecture (72) Inventor Shun Harima             3-5-26, Imazukita, Tsurumi-ku, Osaka-shi, Osaka Prefecture             Inside the chemical industry (72) Inventor Shinichi Hitomi             3-5-26, Imazukita, Tsurumi-ku, Osaka-shi, Osaka Prefecture             Inside the chemical industry (72) Inventor Watanabe 邉 ▼ Junya             3-5-26, Imazukita, Tsurumi-ku, Osaka-shi, Osaka Prefecture             Inside the chemical industry F-term (reference) 4J038 CA022 CB002 CC022 CE052                       CF012 CG142 CH032 CH042                       CH052 CH062 CH072 CH082                       CH122 CH172 CH192 CL002                       DA142 DA162 DA172 DD001                       DD151 DG002 DG262 DG302                       GA02 GA03 JA42 KA03 KA09                       MA02 MA15 NA01 NA11 NA12                       PB03 PB07 PC02 PC08

Claims (8)

[Claims] 1. A resin composition for a colored coating material, which comprises a polyester resin (A) having a hydroxyl group, a curing agent (B), internal cross-linking type fine particles (C) and a urea rheology control agent (D). object. 2. The polyester resin (A) is obtained by reacting a polyhydric alcohol with a polybasic acid of which 60 mol% or more is an alicyclic polybasic acid, and has a weight average molecular weight of 800 to
30,000, solid content hydroxyl value 10-200mgKOH
/ G, the acid value of solid content is 1 to 50 mgKOH / g, The resin composition for colored coating composition according to claim 1. 3. The curing agent (B) is an amino resin and / or a blocked isocyanate compound, according to claim 1 or 2.
The resin composition for colored coating according to item 4. 4. A polyester resin (A) and a curing agent (B)
The resin solid content mass ratio (A / B) is 60/40 to 90 /
The resin composition for colored coating composition according to any one of claims 1 to 3, which is 10. 5. The content of the internally crosslinked fine particles (C) is 1.0 to 300 mass% with respect to the resin solid content mass (A + B).
The resin composition for colored coating according to any one of claims 1 to 4. 6. A urea rheology control agent (D)
Content of 0.0 relative to the resin solid mass (A + B)
The resin composition for colored coating according to any one of claims 1 to 5, which is 1 to 20% by mass. 7. A base paint comprising the resin composition for colored paint according to any one of claims 1 to 6 is applied onto a base material, and then a top clear paint is applied onto the base paint. A laminated coating finishing method, characterized in that a cured coating film is formed. 8. An intermediate coating composition comprising the resin composition for colored coating composition according to any one of claims 1 to 6 is applied onto a substrate, and then a base coating composition is applied onto the intermediate coating composition. Then
Further, a top coating composition is applied onto this base coating composition to form a cured coating film, which is a method for finish of laminated coating.