JPH10183050A - Coating composition and formation of coating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating compsn. which can form a coating film possessing excellent acid resistance, weather resistance and other properties, is less likely to permit deposition of a contaminant, and, even when the contaminant is deposed thereon, enables the contaminant to be easily removed, and can retain the water repellency for a long period of time, and to provide a method for forming a multi-layer coating film. SOLUTION: This coating compsn. is composed mainly of an acrylic copolymer (A) contg. an epoxy group and a hydroxyl group, a carboxyl-contg. compd. (B), and a fluorine-contg. nonaq. dispersion (C). Alternatively, the coating compsn. may be composed mainly of an acrylic copolymer (D) contg. an epoxy group, a hydroxyl group, and a hydrolyzable alkoxysilyl group and the above components (B) and (C). The component (C) is a nonaq. dispersion comprising a polymer particle, contg. a fluoroalkyl-contg. (meth)acrylate, dispersed in an org. solvent contg. a dispersion stabilizer. The method for forming a multi-layer coating uses the above coating compsn. as a clear coating in a two-coat or three-coat system wherein a color coating material and a clear coating material are successively applied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel coating composition and a method for forming a multilayer coating film using the same, and more particularly, to a method for forming a coating film having excellent acid resistance, weather resistance, etc. The present invention relates to a coating composition which is difficult to adhere to a substance, can be easily removed even if it adheres, and can maintain water repellency for a long period of time, and a multilayer coating film forming method using the same.

[0002]

2. Description of the Related Art Damage caused by acid rain such as forest withering due to the progress of air pollution has become a serious social problem, and coatings applied to outer panels of automobiles and the like used outdoors are also etched. And whitening, spots, and the like occur.

[0003] Thermosetting paints using a melamine resin as a cross-linking agent are generally used as outdoor paints, but their acid rain resistance is not sufficient. The reason seems to be that the crosslinked portion of the melamine resin of the cured coating film is hydrolyzed by acid rain or the like and becomes water-soluble. In addition, there is a problem that the coating film is liable to adhere to pollutants such as soot and the removal thereof is difficult.

Further, as a paint having improved acid resistance, weather resistance, etc., an "acid epoxy paint" comprising an acrylic copolymer containing an epoxy group and a hydroxyl group and a carboxyl group-containing compound as main components has been proposed. , Contaminants are easy to adhere, it is difficult to remove the contaminants,
There is a problem that the water repellency is insufficient.

[0005]

Means for Solving the Problems The present inventors have found that acid resistance and weather resistance are equal to or higher than those of acid-epoxy paints, and that contaminants are hardly adhered and can be easily removed even if adhered. After extensive research to develop coating compositions that form coatings that can maintain water repellency over a long period of time, the goal was achieved by blending a fluorine-containing non-aqueous dispersion with an acid epoxy coating. And found that the present invention was completed.

That is, the present invention relates to a coating composition comprising, as main components, an acrylic copolymer containing an epoxy group and a hydroxyl group (A), a compound containing a carboxyl group (B) and a non-aqueous dispersion containing fluorine (C). (This coating material a), 2: mainly composed of an acrylic copolymer (D) containing an epoxy group, a hydroxyl group and a hydrolyzable alkoxysilyl group, a carboxyl group-containing compound (B) and a fluorine-containing non-aqueous dispersion (C). A paint composition as a component (the present paint b); 3: a two-coat system in which a colored paint and a clear paint are sequentially applied, wherein the present paint a or the present paint b is used as a clear paint. Layer coating film forming method (the present method a); 4: In the three-coat system in which a colored paint, a first clear paint, and a second clear paint are sequentially applied, the present paint a or the main paint is used as the second clear paint. 5) a method of forming a multilayer coating film characterized by using a paint b, 5) a three-coat method in which a first colored paint, a second colored paint, and a clear paint are sequentially applied; The present invention also relates to a method for forming a multilayer coating film (the present method c), wherein the present paint a or the present paint b is used.

[0007] The present paint a, the present paint b, the present method a,
The method b and the method c will be described.

The paint a is an organic solvent-based paint composition containing as main components an epoxy- and hydroxyl-containing acrylic copolymer (A), a carboxyl group-containing compound (B) and a fluorine-containing non-aqueous dispersion (C). It is.

The component (A) is an acrylic copolymer in which an epoxy group and a hydroxyl group coexist in the same molecule, for example, an epoxy group-containing polymerizable unsaturated monomer and a hydroxyl group-containing polymerizable unsaturated monomer. And an acrylic copolymer obtained by subjecting another polymerizable unsaturated monomer to a radical copolymerization reaction as required, and an acrylic polymerizable unsaturated monomer as an essential component, and a carboxyl group is substantially contained. Does not exist.

The epoxy group-containing polymerizable unsaturated monomer is a compound having at least one epoxy group and one polymerizable unsaturated bond in one molecule, and examples thereof include glycidyl acrylate and glycidyl methacrylate.

The hydroxyl group-containing polymerizable unsaturated monomer is a compound having at least one hydroxyl group and at least one polymerizable unsaturated bond in one molecule. Examples thereof include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and 3-hydroxyethyl methacrylate. Examples thereof include hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, caprolactone-modified hydroxyethyl acrylate, and caprolactone-modified hydroxyethyl methacrylate.

The acrylic polymerizable unsaturated monomer is a monoester product of acrylic acid or methacrylic acid and a monoalcohol having 1 to 24 carbon atoms, such as methyl acrylate, methyl methacrylate, ethyl acrylate, and ethyl acrylate. Examples include methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, octyl acrylate, octyl methacrylate, stearyl acrylate, and stearyl methacrylate.

The other polymerizable unsaturated monomer is a compound other than the above having one or more polymerizable unsaturated bonds in one molecule, for example, perfluorobutylethyl acrylate,
Fluorine-containing esters of acrylic acid or methacrylic acid such as perfluorobutylethyl methacrylate, perfluoroisononylethyl acrylate, and perfluoroisononylethyl methacrylate; cycloalkyl esters of acrylic acid or methacrylic acid such as cyclohexyl acrylate and cyclohexyl methacrylate; Aromatic compounds such as styrene; and the like, and these unsaturated monomers can be used alone or in combination of two or more.

The component (A) has an epoxy group content of 0.5 to 5.0 mmol / g, particularly 0.8 to 2.5 mmol / g, and a hydroxyl group content of 10 to 200 mg KOH / g.
g, and particularly preferably in the range of 30 to 120 mgKOH / g. When the epoxy group content is less than 0.5 mmol / g, the acid resistance, abrasion resistance and stain resistance of the coating film are increased. When the epoxy group content is more than 5.0 mmol / g, the storage stability of the coating is obtained. Tend to decrease. If the hydroxyl group content is less than 10 mgKOH / g, the acid resistance, abrasion resistance and stain resistance of the coating film are reduced, and the hydroxyl group content is 20%.
If it exceeds 0 mgKOH / g, the water resistance of the coating film tends to decrease. The number average molecular weight is 20
The range of 00 to 50,000, particularly 5000 to 10000 is preferable. The component (B) is a compound having two or more carboxyl groups in one molecule, and has an acid value of 50 to 500 m.
gKOH / g, particularly preferably 80 to 300 mgKOH / g. If the acid value is less than 50 mgKOH / g, the acid resistance and stain resistance of the coating film, etc., and the acid value is 500
If it exceeds mgKOH / g, the water resistance, weather resistance, durability of stain resistance and the like of the coating film tend to decrease. The component (B) has a number average molecular weight of about 300 to about 200.
00, especially about 500 to about 5000 are suitable.

As the component (B), for example, (B-
1): A polymer having a carboxyl group in a side chain, which is a polymer of a polymerizable unsaturated monomer, and (B-2): an esterified product having a carboxyl group.

(B-1) is a polymer using a polymerizable unsaturated monomer and having a carboxyl group in a side chain, for example, a polymer containing a carboxyl group-containing polymerizable monomer. Can be The carboxyl group-containing polymerizable monomer used for preparing the polymer is a compound having at least one carboxyl group and at least one polymerizable unsaturated bond in one molecule. Specifically, an acid anhydride group-containing polymerizable monomer such as maleic anhydride and itaconic anhydride; and the acid anhydride group-containing polymerizable monomer is half-esterified with a low molecular weight monoalcohol such as methanol or ethanol. Polymerizable monomers; free carboxyl group-containing polymerizable monomers such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, mesaconic acid, citraconic acid, and chlorinated maleic acid;
A polymerizable monomer containing two or more free carboxyl groups such as maleic acid, fumaric acid, itaconic acid, mesaconic acid, citraconic acid, and chlorinated maleic acid is half-esterified with a low molecular weight monoalcohol such as methanol or ethanol. Polymerizable monomers; and the like.

The polymer (B-1) is obtained by polymerizing one or more of these carboxyl group-containing polymerizable monomers, or by combining the carboxyl group-containing polymerizable monomer with another polymerizable monomer. It can be prepared by copolymerizing with a polymerizable unsaturated monomer.

The other polymerizable unsaturated monomer is other than the carboxyl group-containing polymerizable monomer, and may be a polymerizable unsaturated monomer exemplified as the component (A), such as an epoxy group-containing polymer. Unsaturated monomers, hydroxyl group-containing polymerizable unsaturated monomers, acrylic polymerizable unsaturated monomers and other polymerizable unsaturated monomers (fluorine-containing esters of acrylic acid or methacrylic acid, acrylic acid Or cycloalkyl esters of methacrylic acid, aromatic compounds such as styrene, etc.). In the copolymer of the carboxyl group-containing polymerizable monomer and these other polymerizable unsaturated monomers, the constituent ratio of the two monomers may be such that the acid value is included in the above range. Are suitable.

A half-ester polymer obtained by half-esterifying a part or all of the acid anhydride groups of a polymer containing an acid anhydride group-containing polymerizable monomer with a low molecular weight monoalcohol is also referred to as a polymer (B-1). ).

Further, a polymer obtained by half-ester addition of a polybasic acid (anhydride) having two or more carboxyl groups per molecule to the hydroxyl group of the polymer having a hydroxyl group in the side chain is also a polymer. It can be applied as (B-1).

(B-2) is a carboxyl group-containing esterified product, for example, a polyol component having two or three or more hydroxyl groups in one molecule and two or three or more carboxyl groups in one molecule. A polyester resin obtained by esterifying a polycarboxylic acid component having a carboxyl group with an excess of a carboxyl group; a hydroxyl group contained in the polyester resin obtained by esterifying the above-mentioned polyol component and a polycarboxylic acid component with an excess of a hydroxyl group. Polyester resin having a carboxyl group at the side chain and / or terminal obtained by half-esterifying a carboxylic acid component; a polyol compound having two or more hydroxyl groups in one molecule (eg, ethylene glycol, propanediol, pentane Diol, neopentyl glycol, glycerin, trimethylolpropane, etc.) An ester compound obtained by half-esterifying 1 mol of a polycarboxylic acid component (for example, succinic anhydride, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc.); And so on.

The polyol component that can be used in these esterification reactions is a compound having two or more hydroxyl groups in one molecule, for example, ethylene glycol having 2 to 10 carbon atoms, propanediol, pentanediol, or the like.
Neopentyl glycol, glycerin, trimethylolpropane and the like. The polyvalent carboxylic acid component has 2 to 3 or more carboxyl groups in one molecule and has 2 to 10 carbon atoms, such as succinic anhydride and maleic anhydride. Phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride and the like.

Component (C): a fluorine-containing non-aqueous dispersion.

Specifically, a non-aqueous dispersion (C-1) in which polymer particles containing a fluoroalkyl group-containing (meth) acrylate are dispersed in an organic solvent liquid containing a dispersion stabilizer, and a fluorine-containing dispersion A non-aqueous dispersion (C-2) in which polymer particles are dispersed in an organic solvent liquid containing a dispersion stabilizer is exemplified. Among them, when (C-1) is used, the contaminants are less likely to adhere than in (C-2), and even if it adheres, the contaminants can be easily removed and the water repellent ability can be maintained for a long time. It is more preferable since a film is formed.

(C-1) is a non-aqueous dispersion in which polymer particles containing (meth) acrylate containing a fluoroalkyl group are dispersed in an organic solvent containing a dispersion stabilizer.

Specifically, polymer particles (C-1c) insoluble in the dispersion stabilizer and the organic solvent are dispersed in the organic solvent (C-1b) containing the dispersion stabilizer (C-1a). Wherein the polymer particles (C-1c) comprise a copolymer of a fluoroalkyl group-containing (meth) acrylate and another polymerizable monomer. .

The dispersion stabilizer (C-1a) is for stably dispersing the polymer particles (C-1c) in the organic solvent (C-1b), and mutually disperses with the organic solvent (C-1b). What can be dissolved in is preferable. Specifically, acrylic resin,
Examples include vinyl resins, polyester resins, alkyd resins, urethane resins, and fluorine-containing resins, and these resins are selected from a hydroxyl group, a carboxyl group, an epoxy group, a silanol group, an alkoxysilane group, and the like, as necessary. One or more functional groups per molecule.

Further, the dispersion stabilizer (C-1a) advantageously has an average of 0.1 or more polymerizable double bonds per molecule. As a method for introducing a polymerizable double bond, for example, a glycidyl group-containing polymerizable monomer (for example, glycidyl acrylate,
Glycidyl methacrylate, allyl glycidyl ether, etc.). Conversely, a carboxyl group-containing polymerizable monomer (for example, acrylic acid, methacrylic acid, maleic acid, fumaric acid) is added to a glycidyl group-containing dispersion stabilizer. Acid, itaconic acid, etc.). Examples of such a combination include an acid anhydride group and a hydroxyl group; an acid anhydride group and a mertaptan group; an isocyanate group and a hydroxyl group. When a polymerizable double bond is introduced into the dispersion stabilizer, a covalent bond is formed between the dispersion stabilizer and the polymer particles (C-1c), and the storage stability and mechanical stability of the non-aqueous dispersion are further improved. It is preferable because it improves.

Although the molecular weight of the dispersion stabilizer (C-1a) is not particularly limited, the weight average molecular weight is about 3,000 to about 100.
000 (about 1000 to about 60000 in number average molecular weight),
Preferably, about 5000 to about 50,000 is suitable.

The organic solvent (C-1b) is the above-mentioned dispersion stabilizer (C-1a), a fluoroalkyl group-containing (meth) acrylate for preparing the polymer particles (C-1c) or other polymerizable compounds. Those that dissolve the monomers but do not substantially dissolve the polymer particles (C-1c) obtained by polymerizing these monomers are included. Accordingly, the organic solvent (C-1b) is selected depending on characteristic values such as the composition and molecular weight of the dispersion stabilizer (C-1a) and the polymer particles (C-1c) actually used. Heptane,
Aliphatic hydrocarbons such as octane, aromatic hydrocarbons such as benzene, xylene, toluene and cyclohexane, methyl acetate, ethyl acetate, isobutyl acetate, acyl acetate, ethylene glycol monomethyl ether acetate;
Ester systems such as ethylhexyl acetate and diethylene glycol monomethyl ether; ether systems such as cellosolve, bricellosolve, isopropyl ether, ethylene glycol monomethyl ether, and diethylene glycol monobutyl ether; ethyl alcohol and isopropyl Alcohols such as alcohol, n-butyl alcohol, i-butyl alcohol, octyl alcohol, hexyl alcohol, methyl isobutyl ketone, diisobutyl ketone, methyl ethyl ketone, isophorone,
Ketone organic solvents such as acetophenone, ethyl acyl ketone, methyl acyl ketone, and ethyl butyl ketone. It is preferable to use mainly an aliphatic hydrocarbon and to use an aromatic hydrocarbon, an alcohol, an ether, an ester or a ketone in combination.

The non-aqueous dispersion (C-1) comprises a dispersion stabilizer (C
-1a) in a mixture of an organic solvent (C-1b) and a copolymer of a fluoroalkyl group-containing (meth) acrylate and another polymerizable monomer and insoluble in the mixture (C
-1c).

The fluoroalkyl group-containing (meth) acrylate (F-acrylate) for obtaining the polymer particles (C-1c) has the general formula CH ₂ 2C (R) -COO- (C
H ₂ ) _n -Rf (R is a hydrogen atom or a methyl group, n is an integer of 1 to 10, and Rf is a linear or branched fluoroalkyl group having 1 to 21 carbon atoms) is there. Here, the “fluoroalkyl group” has 1 to 1 carbon atoms.
A part of or all hydrogen atoms of 21 linear or branched hydrocarbon groups are substituted with fluorine. Such F
Examples of the acrylate include perfluoromethylmethyl acrylate, perfluoromethylmethyl methacrylate, perfluorobutylethyl acrylate, perfluorobutylethyl methacrylate, and perfluoro. Isononylethyl acrylate, perfluoroisononylethyl methacrylate, perfluorooctylethyl acrylate, perfluorooctylethyl methacrylate
2,2,3,3-tetrafluoropropyl acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 1H, 1H, 5H-octafluoropentyl acrylate, 1H, And 1H, 5H-octafluoropentyl methacrylate.

The other polymerizable monomer to be copolymerized with F-acrylate is not particularly limited as long as it is a radically polymerizable unsaturated monomer other than F-acrylate. An example is as follows.

I) Esters of acrylic acid or methacrylic acid: methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate,
Acrylic or methacrylic acid such as isopropyl methacrylate, butyl acrylate, butyl methacrylate, isobornyl acrylate, isobornyl methacrylate, hexyl acrylate, hexyl methacrylate, octyl acrylate, octyl methacrylate, lauryl acrylate, lauryl methacrylate A C _1-20 alkyl ester of
Cyclohexyl acrylate, C _{3 to 20} cycloalkyl esters of acrylic acid or methacrylic acid such as cyclohexyl methacrylate; Ariruakurire - DOO, Arirumetakurire - acrylic acid or methacrylic acid such as preparative C
_2-8 alkenyl esters; allyloxyethyl acrylate les - DOO, allyloxyethyl methacrylate - C _{3 to 20} alkenyloxyalkyl esters of acrylic acid or methacrylic acid such as preparative; and, ii) a glycidyl group-containing unsaturated monomer Glycidyl acrylate, glycidyl methacrylate, etc. iii) Hydroxy group-containing unsaturated monomer: _C2-8 hydroxyalkyl ester of acrylic acid or methacrylic acid; hydroxyethyl acrylate, hydroxyethyl methacrylate Hydroxypropyl acrylate, hydroxypropyl methacrylate; hydroxybutyl vinyl ether
Iv) alkoxysilane group-containing unsaturated monomer: γ-acryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane , Β-acryloyloxyethyltrimethoxysilane, γ-methacryloyloxyethyltrimethoxysilane, γ-acryloyloxypropyltriethoxysilane, γ-methacryloyloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2 V) unsaturated carboxylic acids: acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. vi) isocyanate group-containing unsaturated monomers Isocyanatoethyl acrylate les - DOO, m- isopropenyl-.alpha., alpha-
Vii) unsaturated monomers having two or more polymerizable unsaturated bonds: ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diethylene glycol dimethacrylate; G, trimethylolpropane triacrylate, trimethylol
Viii) vinyl aromatic compounds: styrene, α-methyl styrene, vinyl toluene, p-chlorostyrene vinyl pyridine, etc. ix) others: acrylonitrile, methacrylonitrile, methyl isopropenyl ketone, acetic acid Vinyl, veoba monomer (trade name, manufactured by Shell Chemical Co., Ltd.), vinyl propionate, vinyl pivalate, vinyl propionate, ethylene, propylene, butadiene, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl Methacrylate, acrylamide, vinylpyridine, etc.
The polymer particles (C-1c) in the component (C-1) are F-
It can be prepared by copolymerizing acrylate with another polymerizable monomer. The composition ratio of the two can be arbitrarily selected,
F-acrylate is 90 to 90% based on the total weight of the two components.
1%, especially 30-5%, other polymerizable monomers are 10-99
%, Especially 70-95%, is suitable.

The copolymerization reaction between F-acrylate and another polymerizable monomer is preferably carried out in the presence of a radical polymerization initiator, for example, 2,2-azoisobutyronitrile,
Azo initiators such as 2,2′-azobis (2,4-dimethylvaleronitrile), benzoyl peroxide,
Peroxide initiators such as lauryl peroxide and tert-butyl peroctoate; and the amount of these initiators used is 100 parts by weight in total of F-acrylate and other polymerizable monomers. 0.2 to 10 parts by weight, preferably 0.5 to 5 parts by weight.

In the polymer particles (C-1c), ii) a glycidyl group-containing unsaturated monomer, i.
ii) an unsaturated monomer containing a hydroxyl group, iv) an unsaturated monomer containing an alkoxysilane group, v) an unsaturated carboxylic acid, vi)
By using an isocyanate group-containing unsaturated monomer or the like, polymer particles having these functional groups can be obtained,
These polymer particles can react with a crosslinking agent described later together with the dispersion stabilizer (C-1a) having these functional groups to form a three-dimensionally crosslinked cured coating film. The polymer particles (C-1c) can also be crosslinked in the particles by using vii) an unsaturated monomer having two or more polymerizable unsaturated bonds.

The composition ratio of the dispersion stabilizer (C-1a) to the polymer particles (C-1c) can be arbitrarily selected. For example, based on the total weight of both components, (C-1a) is 3 ~
70%, especially 5 to 60%, (C-1c) is 97 to 30
%, Particularly preferably 95 to 40%. Further, the content of the total amount of the dispersion stabilizer (C-1a) and the polymer particles (C-1c) is (C-1b), (C-1a) and (C-1).
30-70%, especially 40-6%, based on the total weight of c)
0% is preferred.

The polymerization reaction between F-acrylate and other polymerizable monomers in an organic solvent (C-1b) containing a dispersion stabilizer (C-1a) is generally carried out in a temperature range of 60 to 160 ° C. For about 1 to 20 hours. The non-aqueous dispersion (C-1) thus obtained has extremely excellent dispersion stability.

As the component (C), a non-aqueous dispersion (C-1)
Alternatively or simultaneously, a non-aqueous dispersion (C-2) in which polymer particles are dispersed in an organic solvent liquid containing a fluorine-containing dispersion stabilizer can be used.

(C-2) is a non-aqueous dispersion in which polymer particles are dispersed in an organic solvent liquid containing a fluorine-containing dispersion stabilizer. Specifically, a fluorine-containing dispersion stabilizer (C-2a)
Is a non-aqueous dispersion in which polymer particles (C-2c) which are insoluble in an organic solvent (C-2b) containing these are dispersed.

The dispersion stabilizer (C-2a) contains fluorine, and the polymer particles (C-2c) are dissolved in an organic solvent (C-2).
It is for dispersing stably in b) and is preferably soluble in the organic solvent (C-2b). Specifically, the dispersion stabilizer (C-2a) contains the polymer particles (C-
A polymer containing a (fluoro) alkyl group-containing (meth) acrylate (F-acrylate) and / or a fluoroolefin used in the preparation of 1c) can be used. If necessary, a hydroxyl group, a carboxyl group and a carboxyl group may be added to the polymer. Each molecule can have one or more functional groups selected from a group, an epoxy group, a silanol group, an alkoxysilane group, and the like.

As the F-acrylate for preparing the dispersion stabilizer (C-2a), the above-mentioned polymer particles (C-1c)
Can be selected from those exemplified in the description. Examples of the fluoroolefin include tetrafluoroethylene, hexafluoroethylene, chlorotrifluoroethylene, vinyl fluoride, vinylidene fluoride, and trifluoroethylene. Dispersion stabilizer (C-2a)
And at least one selected from these can be used.

The dispersion stabilizer (C-2a) is obtained by polymerizing one or more selected from F-acrylate) and fluoroolefin, or polymerizing these with other polymerizable monomers. Can be prepared. Examples of the other polymerizable monomer include the monomers exemplified in the description of the polymer particles (C-1c). Specifically, i) a C _1-20 alkyl ester of acrylic acid or methacrylic acid _C3-20 cycloalkyl esters of acrylic acid or methacrylic acid; C of acrylic acid or methacrylic acid
_2-8 alkenyl esters; C _{3 to 20} alkenyloxyalkyl esters of acrylic acid or methacrylic acid; and, ii) a glycidyl group-containing unsaturated monomers: iii) C _2-8 hydroxyalkyl esters of acrylic acid or methacrylic acid; Hydroxyalkyl vinyl ether; allyl alcohol, methallyl alcohol, etc., iv) unsaturated monomer containing alkoxysilane group: v) unsaturated carboxylic acid: vi) unsaturated monomer containing isocyanate group: vi
i) unsaturated monomer having two or more polymerizable unsaturated bonds:
viii) Vinyl aromatic compounds: ix) Others: acrylonitrile, methacrylonitrile, methyl isopropenyl ketone, vinyl acetate, veova monomer (manufactured by Shell Chemical Co., trade name), vinyl propionate, vinyl pivalate
, Vinyl propionate, ethylene, propylene, butadiene, N, N-dimethylaminoethyl acrylate,
N, N-dimethylaminoethyl methacrylate, acrylamide, vinylpyridine and the like.

In the dispersion stabilizer (C-2a), in a system obtained by copolymerizing an F-acrylate) and / or a fluoroolefin with another polymerizable monomer, the constituent ratio of the two is optional. Can be selected, and based on the total weight of the two components, F
(Acrylate) and / or fluoroolefin is 100-1%, especially 30-5%, other polymerizable monomers 0
-99%, particularly preferably 70-95%.

The polymerization reaction of one or more selected from F-acrylate) and fluoroolefin, or the copolymerization reaction of these with other polymerizable monomers, is carried out in the presence of a radical polymerization initiator. It is preferably carried out, for example, azo initiators such as 2,2-azoisobutyronitrile and 2,2'-azobis (2,4-dimethylvaleronitrile), benzoyl peroxide, lauryl peroxide, tert-butyl peroxide. Peroxide initiators such as octoate and the like are used. The amount of these initiators used is 0.2 to 0.2 parts by weight per 100 parts by weight of the total of F-acrylate and fluoroolefin and other polymerizable monomers. 10 parts by weight, preferably 0.5 to 5 parts by weight are preferred.

In the dispersion stabilizer (C-2a), as other polymerizable monomers, ii) an unsaturated monomer containing a glycidyl group, iii) an unsaturated monomer containing a hydroxyl group, and iv) an unsaturated monomer containing an alkoxysilane group. Saturated monomers, v) unsaturated carboxylic acids,
vi) By using an isocyanate group-containing unsaturated monomer or the like, dispersion stabilizers having these functional groups can be obtained, and these are polymer particles (C-2c) having these functional groups. ) Together with a crosslinking agent described below to form a three-dimensionally crosslinked cured coating film.

Further, it is advantageous that the dispersion stabilizer (C-2a) has an average of 0.1 or more polymerizable double bonds per molecule. As a method for introducing a polymerizable double bond,
For example, a dispersion stabilizer containing a carboxyl group may be added to a polymerizable monomer containing a glycidyl group (eg, glycidyl acrylate).
Glycidyl methacrylate, allyl glycidyl-ether, etc.). Conversely, a carboxyl group-containing polymerizable monomer (for example, acrylic acid, methacrylic acid, maleic acid, etc.) is added to a glycidyl group-containing dispersion stabilizer. Fumaric acid, itaconic acid, etc.). Examples of such a combination include an acid anhydride group and a hydroxyl group; an acid anhydride group and a mercaptan group; an isocyanate group and a hydroxyl group. When a polymerizable double bond is introduced into the dispersion stabilizer (C-2a), a covalent bond is formed between the dispersion stabilizer and the polymer particles (C-2c), and the storage stability of the non-aqueous dispersion and the mechanical stability It is preferable because stability and the like are further improved.

The molecular weight of the dispersion stabilizer (C-2a) is not particularly limited, but is preferably about 3,000 to about 100 in terms of weight average molecular weight.
000 (about 1000 to about 60000 in number average molecular weight),
Preferably, about 5000 to about 50,000 is suitable.

The organic solvent (C-2b) dissolves the dispersion stabilizer (C-2a) and the polymerizable monomer for preparing the polymer particles (C-2c). Those which do not substantially dissolve the obtained polymer particles (C-2c) are included. Therefore, the organic solvent (C-2b) is selected depending on the characteristic values such as the composition and molecular weight of the dispersion stabilizer (C-2a) and the polymer particles (C-2c) actually used. It is preferable to use a solvent selected from C-1b).

The non-aqueous dispersion (C-2) is prepared by polymerizing with a polymerizable monomer in a mixture of a fluorine-containing dispersion stabilizer (C-2a) and an organic solvent (C-1b). It can be prepared by making polymer particles (C-2c) insoluble in the liquid.

The polymerizable monomer for obtaining the polymer particles (C-2c) is not particularly limited as long as it is a radical polymerizable unsaturated monomer. Specifically, the polymer particles (C-1c) C _{1 to 20} alkyl esters of the illustrated i) acrylic acid or methacrylic acid as the "other polymerizable monomer" described in), acrylic acid or methacrylic acid; C _{3 to 20} cycloalkyl ester of acrylic or methacrylic acid C
_2-8 alkenyl esters; C _{3 to 20} alkenyloxyalkyl esters of acrylic acid or methacrylic acid; and, ii) a glycidyl group-containing unsaturated monomers: iii) C _2-8 hydroxyalkyl esters of acrylic acid or methacrylic acid; Hydroxyalkyl vinyl ether; allyl alcohol, methallyl alcohol, etc., iv) unsaturated monomer containing alkoxysilane group: v) unsaturated carboxylic acid: vi) unsaturated monomer containing isocyanate group: vi
i) unsaturated monomer having two or more polymerizable unsaturated bonds:
viii) Vinyl aromatic compounds: ix) Others: acrylonitrile, methacrylonitrile, methyl isopropenyl ketone, vinyl acetate, veova monomer (manufactured by Shell Chemical Co., trade name), vinyl propionate, vinyl pivalate
, Vinyl propionate, ethylene, propylene, butadiene, N, N-dimethylaminoethyl acrylate,
N, N-dimethylaminoethyl methacrylate, acrylamide, vinylpyridine and the like. Even if F-acrylate coexists as a polymerizable monomer for preparing the polymer particles (C-2c), no problem may occur.

The polymerization reaction of the polymerizable monomer for obtaining the polymer particles (C-2c) is preferably carried out in the presence of a radical polymerization initiator, for example, 2,2-azoisobutyronitrile, Azo initiators such as 2,2'-azobis (2,4-dimethylvaleronitrile), and peroxide initiators such as benzoyl peroxide, lauryl peroxide and tert-butyl peroctoate. The amount of the initiator used is preferably 0.2 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, per 100 parts by weight of the polymerizable monomer.

In the polymer particles (C-2c), ii) a glycidyl group-containing unsaturated monomer, i.
ii) an unsaturated monomer containing a hydroxyl group, iv) an unsaturated monomer containing an alkoxysilane group, v) an unsaturated carboxylic acid, vi)
By using an isocyanate group-containing unsaturated monomer or the like, polymer particles having these functional groups can be obtained,
These are dispersion stabilizers having these functional groups (C
-2a) to react with a crosslinking agent to form a three-dimensionally crosslinked cured coating film. In addition, polymer particles (C
In the case of -2c), intraparticle cross-linking can be performed using vii) an unsaturated monomer having two or more polymerizable unsaturated bonds.

In the non-aqueous dispersion (C-2), the constituent ratio of the dispersion stabilizer (C-2a) to the polymer particles (C-2c) can be arbitrarily selected. For example, the total weight of the two components can be selected. (C-2a) is 3 to 70%, particularly 5 to 60%,
(C-2c) is preferably 97 to 30%, particularly preferably 95 to 40%. Further, the dispersion stabilizer (C-2a) and the polymer particles (C
-2c) is 30 to 70% based on the total weight of (C-2b), (C-2a) and (C-2c).
Particularly, 40 to 60% is preferable.

The polymerization reaction of the polymerizable monomer for obtaining the polymer particles (C-2c) in the organic solvent (C-2b) containing the dispersion stabilizer (C-2a) is generally performed at 60 to 160 ° C. The temperature is preferably about 1 to 20 hours. The non-aqueous dispersion (C-2) thus obtained is extremely excellent in dispersion stability.

The paint a contains the above components (A), (B) and (C) as main components and, if necessary, uses these components in an organic solvent (for example, an aromatic solvent such as toluene or xylene, acetic acid). Esters such as butyl, methyl ethyl ketone,
And organic solvent-based coating compositions mixed with ketones such as methyl isobutyl ketone and alcohols such as propyl alcohol and butanol.

The composition ratio of these components can be arbitrarily selected according to the purpose. For example, the component (A) is 50 to 9 based on the total solid content of both the component (A) and the component (B).
0% by weight, particularly 65 to 85% by weight, and the component (B) is 50 to 85% by weight.
The content is preferably 10% by weight, particularly preferably 35 to 15% by weight, and the component (C) is a total solid content of the components (A) and (B) of 1
0.5 to 40 parts by weight, especially 2 to 30 parts by weight, per 100 parts by weight
Parts by weight are preferred.

The coating material (a) may optionally contain a curing catalyst,
Color pigments, extenders, ultraviolet absorbers, antioxidants, surface conditioners, and the like can be added.

Further, the present coating material (a) containing the above-mentioned components (A), (B) and (C) as main components further comprises an amino resin, an optionally blocked polyisocyanate compound, (Alkoxycarbonylamino) triazine and the like can be blended.

Examples of the amino resin include a methylolated amino resin obtained by reacting an aldehyde compound with an amino compound such as melamine, urea, benzoguanamine, acetoguanamine, steloguanamine and dicyandiamide. Examples of the aldehyde compound include formaldehyde, paraformaldehyde, acetaldehyde, and benzaldehyde. Further, those obtained by etherifying the methylolated amino resin with an alcohol having 1 to 10 carbon atoms can also be used. Specific examples of alcohols usable for etherification include methyl alcohol, ethyl alcohol, n-propyl alcohol, and i.
-Propyl alcohol, n-butyl alcohol, i-butyl alcohol, 2-ethylbutanol, 2-ethylhexanol and the like.

The polyisocyanate compound is a compound having two or more isocyanate groups in one molecule, for example, hexamethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate. −
Aliphatic diisocyanates such as diisocyanate, dimer acid diisocyanate and lysine diisocyanate; isophorone diisocyanate, methylene bis (cyclohexyl isocyanate), methylcyclohexane diisocyanate;
Alicyclic diisocyanates such as cyclohexane diisocyanate and cyclopentane diisocyanate; xylylene diisocyanate, tolylene diisocyanate,
Aromatic diisocyanates such as diphenylmethane diisocyanate, naphthalene diisocyanate, and toluidine diisocyanate; urethanized adducts, biuret-type adducts, and isocyanuric ring-type adducts of the polyisocyanate compounds Things.

In these polyisocyanate compounds, the isocyanate group of the compound may be blocked. Examples of such a blocking agent include phenol-based, lactam-based, active methylene-based and alcohol-based compounds. System, mercaptan system, acid amide system, imide system, amine system, imidazole system, urea system, carbamic acid system, imine system and oxime system.

The carbon number of the hydrocarbon moiety in tris (alkoxycarbonylamino) triazine is 1-2.
Zero is preferred, and methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n An alkyl group such as -hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decanyl group, n-dodecanyl group, n-undecanyl group; cycloalkyl group such as cyclopentyl and cyclohexyl; cyclohexylmethyl; Cycloalkylalkyl groups such as cyclohexylethyl; allyl groups such as phenyl, biphenyl, alkyl-substituted phenyl and naphthyl;
Aralkyl groups such as benzyl and phenethyl; and the like.

The paint b mainly comprises an acrylic copolymer (D) containing an epoxy group, a hydroxyl group and a hydrolyzable alkoxysilyl group, a carboxyl group-containing compound (B) and a fluorine-containing non-aqueous dispersion (C). An organic solvent-based coating composition as a component, wherein the component (A) of the coating material (a) is replaced with the component (D).

Among these components of the present paint b, those selected from those described above for the present paint a can be applied to the components (B) and (C).

The component (D) is an acrylic copolymer containing an epoxy group, a hydroxyl group and a hydrolyzable alkoxysilyl group. Examples thereof include an epoxy group-containing polymerizable unsaturated monomer and a hydroxyl group-containing polymerizable unsaturated monomer. A monomer, a hydrolyzable alkoxysilyl group-containing polymerizable unsaturated monomer and an acrylic polymerizable unsaturated monomer are essential components, and other polymerizable unsaturated monomers are used as necessary, according to a conventional method. To obtain a radical copolymerization reaction. Among these monomers, the epoxy group-containing polymerizable unsaturated monomer, the hydroxyl group-containing polymerizable unsaturated monomer, the acrylic polymerizable unsaturated monomer and other polymerizable unsaturated monomers are as described above. Those exemplified as the component (A) can be suitably used.

The hydrolyzable alkoxysilyl group-containing polymerizable unsaturated monomer is a compound having at least one hydrolyzable alkoxysilyl group and at least one polymerizable unsaturated bond in one molecule. ) Contains hydrolyzable alkoxysilyl groups such as acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane, γ- (meth) acryloyloxypropylmethyldimethoxysilane, vinyltrimethoxysilane and vinylmethyldimethoxysilane Acrylic monomers and the like.

In the component (D), the epoxy group content is preferably 0.5 to 5.0 mmol / g, particularly preferably 0.8 to 2.5 mmol / g. Acid resistance, abrasion resistance and stain resistance of the film,
If it exceeds 5.0 mmol / g, the stain resistance tends to decrease. Hydroxyl content is 10 to 200
mgKOH / g, and particularly preferably in the range of 30 to 120 mgKOH / g, the acid resistance, abrasion resistance and stain resistance of the coating film become lower when it is lower than 10 mgKOH / g, and the water resistance of the coating film when it becomes higher than 200 mgKOH / g. Tend to decrease.
The hydrolyzable alkoxysilyl group is preferably in the range of 0.1 to 5.0 mmol / g, particularly preferably in the range of 1.0 to 3.0 mmol / g. Abrasion resistance decreases, and if it is more than 5.0 mmol / g, the cost increases. The number average molecular weight is 2
When it is less than 2000, the weather resistance and stain resistance of the cured coating film tend to decrease, and when it exceeds 50,000, the stain resistance tends to decrease.

The paint b has the above-mentioned components (D), (B) and (C) as main components. If necessary, these components may be mixed with an organic solvent (for example, aromatics such as toluene and xylene, acetic acid). Esters such as butyl, methyl ethyl ketone,
And organic solvent-based coating compositions mixed with ketones such as methyl isobutyl ketone and alcohols such as propyl alcohol and butanol.

The composition ratio of each component can be arbitrarily selected according to the purpose. For example, the component (D) is 50 to 9 based on the total solid content of both the component (D) and the component (B).
0% by weight, particularly 65 to 85% by weight, and the component (B) is 50 to 85% by weight.
The content is preferably 10% by weight, particularly preferably 35 to 15% by weight.
0.5 to 40 parts by weight, especially 2 to 30 parts by weight, per 100 parts by weight
Parts by weight are preferred.

The paint b may optionally contain a curing catalyst,
Color pigments, extenders, ultraviolet absorbers, antioxidants, surface conditioners, and the like can be added.

The paint b having the above components (D), (B) and (C) as main components is further coated with an amino resin, a polyisocyanate compound which may be blocked, a tris (Alkoxycarbonylamino) triazine and the like can be blended. Specific examples thereof include those described for the present paint a, and a crosslinking agent selected from these can be used in the present paint b.

The paint a and the paint b may be prepared by adding the above components to an organic solvent (for example, an aromatic solvent such as toluene and xylene, an ester solvent such as butyl acetate, a ketone solvent such as methyl ethyl ketone and methyl isobutyl ketone). Propyl alcohol, butanol, etc.) and used as an organic solvent-based paint.

The present paint a and the present paint b can be applied by air spray coating, airless spray coating, electrostatic coating, or the like. The solid content at the time of coating is usually 30 to 80% by weight, particularly 40 to 75% by weight. Is preferred. The coating thickness is preferably 5 to 60 μm, particularly preferably 10 to 40 μm.
The composition can be cured by heating at 00 to 180 ° C. for 10 to 60 minutes.

The thus-obtained single coating film has acid resistance, weather resistance and the like which are equal to or higher than those of the acid-epoxy paint, and hardly adheres contaminants. Since the performance can be maintained for a long period of time, it is preferable to apply it to the uppermost coating film of an automobile outer panel where these performances are required.

As a specific example in which the present paint a and the present paint b are applied to the outer panel of an automobile, there are the following coating methods.

Method a: In a two-coat system in which a colored paint and a clear paint are sequentially applied, the paint composition according to claim 1 or 2 is used as the clear paint.

Method b: In a three-coat system in which a colored paint, a first clear paint and a second clear paint are sequentially applied, the paint composition according to claim 1 or 2 is used as the second clear paint.

Method c: In a three-coat system in which a first colored paint, a second colored paint, and a clear paint are sequentially applied,
The coating composition according to claim 1 or 2 is used as the clear coating.

Examples of the object to which these coating methods are applied include metal and plastic automobile outer panels, and these may be subjected to surface treatment, undercoating (for example, cationic electrodeposition primer coating) and medium coating if necessary. It is preferable to perform painting and the like.

Method a: In a two-coat system in which a colored paint and a clear paint are sequentially applied, the present paint a or the present paint b is used as the clear paint.

After applying the colored paint on the object to be coated and curing by heating, or with the uncured material, the present paint a or the present paint b is applied as a clear paint, and then heated to cure the coated film. This is done by: That is, the two-coat system includes a two-coat one-bake system and a two-coat two-bake system.

Examples of the coloring paint include an aqueous or organic solvent-based paint containing a thermosetting resin composition and a coloring pigment as main components.

The thermosetting resin composition comprises a hydroxyl group-containing resin and a crosslinking agent. Examples of the hydroxyl group-containing resin include known resins such as a polyester resin, an acrylic resin, an alkyd resin, and a urethane resin containing two or more hydroxyl groups in one molecule and, if necessary, a carboxyl group.
The hydroxyl value of these hydroxyl group-containing resins is 20 to 200 mg.
KOH / g, particularly 25 to 180 mg KOH / g, acid value of 50 mg KOH / g or less, number average molecular weight of 1,000 to
Those in the range of 100,000 are preferred. Examples of the cross-linking agent include melamine resins and urea resins partially or wholly etherified with a monoalcohol having 1 to 10 carbon atoms; polyisocyanate compounds which may be blocked. The mixing ratio of the hydroxyl group-containing resin and the crosslinking agent is
Based on the total solid content weight of both, the former is in the range of 50 to 90% by weight, preferably 60 to 80% by weight, and the crosslinking agent is in the range of 50 to 10% by weight, preferably 40 to 20% by weight.

Examples of the coloring pigment in the coloring paint include solid color pigments; metallic pigments such as flaky aluminum powder, copper powder, nickel powder, stainless steel powder, and colored mica powder; interference pigments; and the like. The amount of the pigment varies depending on the type and shape of the pigment, but is preferably about 1 to 200 parts by weight based on 100 parts by weight of the solid content of the thermosetting resin composition.

In the two-coat system, the color paint and the clear paint (the present paint a or b) can be applied by spray coating or electrostatic coating. The colored paint is applied to the object to be coated in a thickness of about 10 to 50 μm, preferably about 15 to 40 μm based on the cured coating film.
And then leave it at room temperature or
At a temperature of 200 ° C. for about 10-60 minutes, preferably about 20
After heating and curing for about 40 minutes, the clear coating of the present coating a or b is applied to the uncured or cured coating surface in an amount of about 20 to 100 μm, preferably about 25 to 8 μm, based on the cured film thickness.
This method (a) is carried out by applying a coating having a thickness of 0 μm and then heating and curing at a temperature of about 120 to 200 ° C. for about 10 to 60 minutes, preferably for about 20 to 40 minutes.

Method b: In a three-coat system in which a colored paint, a first clear paint and a second clear paint are sequentially applied, the present paint a or the present paint b is used as the second clear paint.
Use painting method.

Specifically, a colored paint is applied to the object to be coated and cured by heating (can be omitted). A first clear paint is applied to the coated surface and cured by heating (can be omitted). Alternatively, after the main coating material a or the main coating material b is applied as the second clear coating material, the coating film is cured by heating. That is, the three-coat system includes a three-coat one-bake system, a three-coat two-bake system, and a three-coat three-bake system.

As the coloring paint, the paint described in the two-coat method can be used.

The first clear paint is a paint having a composition obtained by removing all or a part of the coloring pigment from the coloring paint and capable of forming a colorless transparent or colored transparent coating film. Then, the present paint a or the present paint b is used as the second clear paint to form a colorless transparent or colored transparent coating film.

The application of the coloring paint, the first clear paint and the second clear paint can be performed by spray coating, electrostatic coating or the like. A colored paint is applied to the substrate to a thickness of about 10 to 50 μm, preferably about 15 to 40 μm based on the cured coating film, and left at room temperature or about 120 to 200 ° C.
At a temperature of about 10 to 60 minutes, preferably about 20 to 40 minutes, and then cure the first clear coating on the uncured or cured coating surface for about 20 to 10 minutes based on the cured film thickness.
0 μm, preferably about 25-80 μm,
After leaving at room temperature or heating at a temperature of about 120 to 200 ° C. for about 10 to 60 minutes, preferably for about 20 to 40 minutes, the second clear paint is applied to the uncured or cured coated surface. About 20-100 μm based on the cured film thickness,
Preferably, it is applied to a thickness of about 25 to 80 μm,
At a temperature of about 200 DEG C. for about 10 to 60 minutes, preferably about 2 hours.
Method b by heating and curing for 0-40 minutes
Is performed.

Method c: In a three-coat system in which a first colored paint, a second colored paint and a clear paint are sequentially applied,
The coating composition according to claim 1 or 2 is used as the clear coating.

More specifically, a first colored paint is applied to the object to be coated, cured by heating (can be omitted), and then a second colored paint is applied to the coated surface.
The coating can be carried out by applying a colored paint, heating and curing (can be omitted), applying the present paint a or the present paint b as a clear paint, and then heating and curing the coating film. In other words, this three-coat system is a three-coat one-bake system,
The three-coat two-bake system and the three-coat three-bake system are included.

As the first colored paint, the paint described in the two-coat method can be used, and it is preferable to use a solid color or metallic paint.

It is preferable that the second colored paint has such transparency that the first colored paint film can be visually recognized through the paint film, and a transparent or translucent paint film having such properties is formed. A solid color paint, a metallic paint, or an interference paint can be used, and the composition can use the paint described in the two-coat method. Then, using the present paint a or the present paint b as the clear paint, a colorless transparent or colored transparent coating film is formed.

The first color paint, the second color paint and the clear paint can be applied by spray coating or electrostatic coating. The first colored paint is applied to the substrate to a thickness of about 10 to 50 μm, preferably about 15 to 40 μm based on the cured coating film, and left at room temperature or about 120 to 200 μm.
At a temperature of about 10 to 60 minutes, preferably about 20 to 40 minutes.
After curing by heating for 2 minutes, a second colored paint is applied to the uncured or cured coating surface for about 20 to 10 based on the cured film thickness.
0 μm, preferably about 25-80 μm,
After leaving it to stand at room temperature or by heating it at a temperature of about 120 to 200 ° C. for about 10 to 60 minutes, preferably for about 20 to 40 minutes, apply a clear coating to the uncured or cured coated surface. About 20 to 100 μm, preferably about 25 to 80 μm, based on the thickness;
At a temperature of 00 ° C. for about 10 to 60 minutes, preferably about 20 to
The method c is performed by heating and curing for 40 minutes.

Advantageous Effects of the Invention A coating composition which is excellent in acid resistance, weather resistance, etc., hardly adheres contaminants, can be easily removed even if it adheres, and can maintain water repellency for a long time. A multi-layer coating film forming method using it has been developed.

Examples of the present invention will be described below. Examples and comparative examples according to the present invention will be described below. Parts and percentages are all based on weight.

1. Sample 1) Acrylic copolymer solution containing epoxy group and hydroxyl group (A-1) Glycidyl methacrylate / 2-hydroxyethyl acrylate / n-butyl acrylate / methyl methacrylate / styrene = 35/15/15/15/20 (weight) Copolymer). Number average molecular weight 7000, solid content 70% by weight xylene solution, epoxy group content 2.46 mmol / g, hydroxyl group content 78 mgKOH / g.

2) Acrylic copolymer solution containing epoxy group, hydroxyl group and hydrolyzable alkoxysilane group (D-
1) Glycidyl methacrylate / 2-hydroxyethyl acrylate / n-butyl acrylate / γ-methacryloxypropyltrimethoxysilane / styrene = 35 /
15/15/15/20 (weight ratio) copolymer. Number average molecular weight 7500, solid content 70% by weight xylene solution, epoxy group content 2.46 mmol / g, hydroxyl group content 78
mgKOH / g, hydrolyzable alkoxysilane group content 1.8 mmol / g.

3) Carboxyl group-containing compound solution (B-
1) Methanol half esterified maleic anhydride / 2-hydroxyethyl acrylate / n-butyl acrylate / styrene = 20/20/40/20 (weight ratio), number average molecular weight 3500, solid content 55% by weight, acid 86mgK
OH / g.

4) Carboxyl group-containing compound solution (B-
2) 1 mol of trimethylolpropane and 2 mol of hexahydrophthalic anhydride were subjected to a half-esterification reaction in xylene to obtain a carboxyl group-containing compound solution having a solid content of 70%. This compound had an acid value of 252 mgKOH / g, a hydroxyl value of 126 mgKOH / g, and a molecular weight of 446.

5) Nonaqueous Dispersion (C-1) A mixture of 95 parts of heptane and 121 parts of a dispersion stabilizer (Note 1) was heated to reflux temperature, and 10 parts of perfluorooctylethyl methacrylate and styrene were added. A mixture consisting of 10 parts, 25 parts of methyl methacrylate, 30 parts of acrylonitrile, 25 parts of 2-hydroxyethyl methacrylate and 1.5 parts of 2,2'-azobisisobutyronitrile was added dropwise over 3 hours. The mixture was further aged at the same temperature for 2 hours to obtain a non-aqueous dispersion (C-1). The solid content was 53%, the viscosity (gardner-25 ° C) C, the appearance was milky white, and the particle size (electron microscope) was 0.2 to 0.3 µm. Particles / Stabilizer = 6
0/40, particles only contain perfluoro groups.

(Note 1) Dispersion stabilizer: isobutyl acetate 40
Styrene, 50 parts of isobutyl methacrylate, 9 parts of butyl acrylate, cyclohexyl methacrylate 1
0 parts, 2-ethylhexyl methacrylate 10 parts, methacrylic acid 1 part, 2-hydroxyethyl methacrylate 1
A mixture consisting of 0 parts and 2 parts of 2,2'-azobisisobutyronitrile was added dropwise over 3 hours, and the mixture was aged at the same temperature for 2 hours to obtain a hydroxyl group-containing acrylic resin. The solid content was 55%, the viscosity (gardner-25 ° C) N, and the weight average molecular weight was 16,000.

6) Non-aqueous dispersion (C-2) A mixture of 93 parts of heptane and 98 parts of a dispersion stabilizer (Note 2) was heated to the reflux temperature, and 5 parts of perfluorooctylethyl methacrylate, styrene 15 parts, methyl methacrylate
And a mixture of 28 parts of acrylonitrile, 18 parts of 2-hydroxyethyl methacrylate and 2 parts of 2,2'-azobisisobutyronitrile was added dropwise over 3 hours, and the mixture was aged at the same temperature for 2 hours. Non-aqueous dispersion (C
-2) was obtained. Solids content 53%, viscosity (gardner-25 ° C) A, appearance milky white, particle size (electron microscope)
It was 2-0.3 μm. Particles / stabilizer = 65/35,
Contains perfluoro groups in both the stabilizer and the particles.

(Note 2) Dispersion stabilizer: isobutyl acetate 30
Styrene, 30 parts of isobutyl methacrylate,
15 parts of perfluorooctylethyl methacrylate, 5 parts of butyl acrylate, 10 parts of cyclohexyl methacrylate, 14 parts of 2-ethylhexyl methacrylate, 1 part of methacrylic acid, 2-hydroxyethyl methacrylate 15 And a mixture consisting of 6 parts of t-butylperoxy-2-ethylhexanoate was added dropwise over 3 hours, followed by aging at the same temperature for 2 hours to obtain a perfluoro group-containing acrylic polyol resin. The solid content was 55%, the viscosity (gardner-25 ° C.) G, and the weight average molecular weight was 6,000.

7) Non-aqueous dispersion (C-3) A mixture of 90 parts of heptane and 121 parts of a dispersion stabilizer (Note 3) was heated to the reflux temperature, and 25 parts of perfluoromethylmethyl methacrylate, styrene A mixture consisting of 10 parts, 15 parts of methyl methacrylate, 25 parts of acrylonitrile, 25 parts of 2-hydroxyethyl methacrylate and 2 parts of t-butylperoxy-2-ethylhexanoate was added dropwise over 3 hours. The mixture was further aged at the same temperature for 2 hours to obtain a non-aqueous dispersion liquid (C-3). The solid content was 53%, the viscosity (gardner-25 ° C) C, the appearance was milky white, and the particle size (electron microscope) was 0.18 to 0.25 µm. Particle / stabilizer =
60/40, double bond introduced into stabilizer, perfluoro group contained in particles.

(Note 3) Dispersion stabilizer: isobutyl acetate 30
At the reflux temperature of a solvent consisting of 10 parts of toluene and 50 parts of toluene, 10 parts of styrene, 20 parts of butyl methacrylate, 34 parts of isobutyl methacrylate, 5 parts of butyl acrylate,
-A mixture comprising 15 parts of ethylhexyl methacrylate, 1 part of methacrylic acid, 15 parts of 2-hydroxyethyl methacrylate and 2 parts of 2,2'-azobisisobutyronitrile was added dropwise over 3 hours. After aging at the same temperature for 2 hours, glycidyl methacrylate 0.8
, 0.02 parts of 4-tert-butylpyrocatechol and 0.1 part of dimethylethanolamine were added and reacted to introduce a polymerizable double bond. Solids content is 55
%, Viscosity (gardner-25 ° C) L, weight average molecular weight 16
000, having about 0.6 polymerizable double bonds per molecule.

8) Non-aqueous Dispersion (C-4) A mixture of 93 parts of heptane and 149 parts of a dispersion stabilizer (Note 3) was heated to reflux temperature, and 10 parts of perfluorooctylethyl methacrylate, styrene 10 parts, methyl methacrylate 27 parts, acrylonitrile 30 parts, 2-hydroxyethyl methacrylate 15 parts, glycidyl methacrylate 5 parts, acrylic acid 3 parts and 2,2'-azobisisobutyronitrile A mixture of 2 parts was added dropwise over 3 hours, and aged at the same temperature for 2 hours to obtain NAD.
Solids content 53%, viscosity (gardner-25 ° C) C,
Appearance Milky white, particle size (electron microscope) 0.15-0.2μ
m. Particle / stabilizer = 55/45, double bond introduced into stabilizer, intra-particle crosslinking, perfluoro group contained in particle. .

9) Non-aqueous dispersion (C-5) A mixture of 95 parts of heptane and 121 parts of a dispersion stabilizer (Note 2) was heated to reflux temperature, and 15 parts of styrene, 25 parts of methyl methacrylate, and acrylonitrile were used. A mixture of 35 parts, 25 parts of 2-hydroxyethyl methacrylate and 1.5 parts of 2,2'-azobisisobutyronitrile was added dropwise over 3 hours, and the mixture was aged at the same temperature for 2 hours to obtain a non- An aqueous dispersion (C-5) was obtained. The solid content was 53%, the viscosity (gardner-25 ° C) A, the appearance was milky white, and the particle size (electron microscope) was 0.2 to 0.3 µm. Particles / Stabilizer = 6
0/40, containing perfluoro group in stabilizer.

10) Non-aqueous dispersion (C-6) 110 parts of heptane and "Lumiflon LF200" 108
Of styrene, 30 parts of methyl methacrylate, 35 parts of acrylonitrile,
20 parts of 2-hydroxyethyl methacrylate and 2,
A mixture comprising 2 parts of 2'-azobisisobutyronitrile was added dropwise over 3 hours, and the mixture was aged at the same temperature for 2 hours to obtain a non-aqueous dispersion (C-6). Solids content is 52
%, Viscosity (gardner-25 ° C) B, appearance Milky white, particle size (electron microscope): 0.15 to 0.2 µm. "Lumiflon LF200" is a 60% solution of fluoroolefin resin under the trade name of Asahi Glass. Particles / stabilizer = 60/40, stabilizer contains perfluoroolefin.

11) Non-aqueous dispersion (C-7) A mixture of 95 parts of comparative heptane and 121 parts of a dispersion stabilizer (Note 1) was heated to reflux temperature, and 10 parts of styrene and 40 parts of methyl methacrylate were heated. Acrylonitrile, 20 parts of 2-hydroxyethyl methacrylate and t-butyl
A mixture consisting of 2 parts of oxy-2-ethylhexanoate was added dropwise over 3 hours, and aged at the same temperature for 2 hours to obtain NAD. Solid content 53%, viscosity (gardner-25 ° C) C, appearance milky white, particle size (electron microscope)
It was 2-0.3 μm. Particles / stabilizer = 60/40,
Stabilizers and particles do not contain fluorine.

[0113] 2. Examples 1 to 6 and Comparative Examples 1 to 3 The present paint a and the present paint b were prepared according to the formulation (solid content) shown in Table 1 and had a viscosity of 25 using Swazole 1000 (manufactured by Cosmo Oil Co., Ltd .; trade name). Second (Ford Cup No. 4/20
° C).

These compositions were applied to a glass plate so that the thickness of the cured coating film became 25 μm, and the coating was cured by heating at 140 ° C. for 30 minutes. A performance test was performed on this coating film, and the results are also shown in the same table.

[0115]

[Table 1]

The test method is as follows.

Initial oil repellency: This is the result of measuring the paraffin contact angle of a coating film which was cured by heating at 140 ° C. for 30 minutes and allowed to stand at room temperature for 1 hour.
c, and the contact angle between the droplet and the coating surface was measured using a “contact angle meter CA-X150” (trade name) manufactured by Kyowa Interface Science Co., Ltd.

Initial water repellency: This is the result of measuring the water contact angle of a coating film which was heated and cured at 140 ° C. for 30 minutes and left at room temperature for 1 hour. 0.03 cc of water was dropped on the coated surface, and the water droplet was applied to the coated surface. Kyowa Interface Science Co., Ltd., contact angle meter CA-
X150 "(trade name).

Long-term water repellency: After the cured coating film was exposed for 500 hours with a sunshine weatherometer, the water contact angle of the coated surface was measured in the same manner as described above.

Acid resistance: 0.5 ml of a 40% sulfuric acid aqueous solution was dropped on the coated surface, heated at 70 ° C. for 20 minutes, washed with water, and the state of the coated surface was evaluated. Among the abnormalities (No) at all (O) and abnormalities (X) such as remarkable gloss and blisters, the three stages of O, Δ, and X were determined in order from the best one according to the degree.

Comparative Example 3 in Table 1 is an organic solvent-based coating material containing a hydroxyl group-containing acrylic resin and a melamine resin as main components and a fluorine-containing non-aqueous dispersion. The hydroxyl group-containing acrylic resin has a hydroxyl value of 90 mg KOH / g, a number average molecular weight of 12000, and the melamine resin is a butyl etherified melamine resin, and has a viscosity of 25 seconds (Ford Cup N, manufactured by Cosmo Oil Co., Ltd .; trade name).
o. 4/20 ° C).

3. Examples 7 to 10 and Comparative Examples 4 to 6 A method for forming a top coat by a two-coat one-bake method (2C1B): 0.8 mm thick subjected to a zinc phosphate chemical conversion treatment
Electrodeposition coating of an epoxy-based cationic electrodeposition paint to a cured film thickness of about 20 μm, baking at 170 ° C. for 20 minutes, sharpening with sandpaper # 400, wiping with petroleum benzene and degreasing Then, an intermediate coating surfacer for automobiles is applied by air spraying so as to have a dry film thickness of about 25 μm, and baked at 140 ° C. for 30 minutes.
The material was sanded with a sandpaper of No. 00, drained and dried, and then wiped with petroleum benzene to degrease it to obtain a test material.

A colored paint (having a hydroxyl value of 72 mg)
30 g of Cymel 202 (manufactured by Mitsui Cytec Co., Ltd., trade name, melamine resin with a solid content of 80% by weight) to 70 g of a hydroxyl group-containing acrylic resin (solid content) having a KOH / g and a number average molecular weight of 12,000 30 g (solid content) of aluminum paste (Toyo) A mixture of 20 g (solid content) of Alpaste 1830YL manufactured by Aluminum Co., Ltd. was mixed with a mixed solvent (toluene / isobutylarylol / cellosolve acetate = 40 g / 3).
0 g / 30 g) and diluted to a viscosity of 16 seconds at 4/20 ° C. Ford Cup No.) in a cured film thickness of 30 μm.
m, and forcibly dried at 80 ° C. for 10 minutes. Then, the uncured coating surface is spray-coated with a clear coating composed of the compositions of Examples and Comparative Examples to a cured film thickness of 40 μm. The coating was heated at 140 ° C. for 30 minutes to cure both coatings, thereby forming an overcoat (two-coat one-bake method).

Table 2 shows the application steps of the colored paint (metallic paint) and the clear paint, and the performance test results of the obtained multilayer coating film.

[0125]

[Table 2]

4. Examples 12 to 15 and Comparative Examples 7 to 9 A method for forming a top coat by a three-coat two-bake method (3C2B): On the test material used in 2C1B above,
The same colored paint (metallic paint) as above is spray-coated so as to have a cured film thickness of 20 μm, and is forcibly dried at 80 ° C. for 10 minutes. Then, a first clear coat (having a hydroxyl value of 72 mg KOH / g) is applied to the uncured film surface. , Number average molecular weight 120
CYMER 202 (manufactured by Mitsui Cytec, trade name, solid content 80)
30% by weight (solid content) of a melamine resin) was mixed with a mixed solvent (toluene / isobutylarylol /
Sprayed with Ford cup No. 4/20 ° C diluted to a viscosity of 16 seconds with cellosolve acetate = 40 g / 30 g / 30 g), spray-coated to a cured film thickness of 20 μm, and heated at 140 ° C for 30 minutes After the two coatings were cured, after cooling, they were spray-coated so as to have a cured film thickness of 20 μm using a second clear coating composed of the compositions of Examples and Comparative Examples, and heated at 140 ° C. for 30 minutes. Thus, a top coat was formed.

Table 3 shows the coating process of the colored paint (metallic paint), the first clear paint and the first clear paint, and the performance test results of the obtained multilayer coating film.

[0128]

[Table 3]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C09D 143/04 C09D 143/04 (72) Inventor Yoshizumi Matsuno 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Kansai Paint Co., Ltd. Inside

Claims (7)

[Claims] 1. A coating composition comprising, as main components, an acrylic copolymer containing an epoxy group and a hydroxyl group (A), a compound containing a carboxyl group (B), and a non-aqueous dispersion containing fluorine (C). 2. An acrylic copolymer (D) containing an epoxy group, a hydroxyl group and a hydrolyzable alkoxysilyl group,
A coating composition comprising a carboxyl group-containing compound (B) and a fluorine-containing non-aqueous dispersion (C) as main components. 3. A non-aqueous dispersion comprising a fluorine-containing non-aqueous dispersion (C) in which polymer particles containing a (fluoro) alkyl group-containing (meth) acrylate are dispersed in an organic solvent containing a dispersion stabilizer. The coating composition according to claim 1, wherein: 4. The fluorine-containing non-aqueous dispersion (C) is a non-aqueous dispersion in which polymer particles are dispersed in an organic solvent containing a fluorine-containing dispersion stabilizer. Or the coating composition of 2. 5. A method for forming a multi-layer coating film according to claim 1, wherein said coating composition according to claim 1 or 2 is used as said clear coating in a two-coat system in which a coloring coating and a clear coating are sequentially applied. 6. A three-coat system in which a colored paint, a first clear paint and a second clear paint are sequentially applied, wherein the paint composition according to claim 1 or 2 is used as the second clear paint. To form a multilayer coating film. 7. A three-coat system in which a first color paint, a second color paint, and a clear paint are sequentially applied, wherein the paint composition according to claim 1 or 2 is used as the clear paint. Multi-layer coating film forming method.