WO2006028130A1

WO2006028130A1 - Hydroxyl group-containing resin for coating material and coating composition

Info

Publication number: WO2006028130A1
Application number: PCT/JP2005/016417
Authority: WO
Inventors: Yoshiyuki Yukawa; Toshiyuki Hanaoka
Original assignee: Kansai Paint Co., Ltd.
Priority date: 2004-09-08
Filing date: 2005-09-07
Publication date: 2006-03-16
Also published as: JPWO2006028130A1; JP5142525B2

Abstract

Disclosed is a hydroxyl group-containing resin for coating material having a weight average molecular weight of 1,500-30,000 and a hydroxyl number of 120-180 mgKOH/g. Such a hydroxyl group-containing resin for coating material is obtained by copolymerizing a monomer mixture containing (a) an alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 3-20 carbon atoms, (b) styrene, (c) a hydroxyl group-containing polymerizable unsaturated monomer, (d) a hydrocarbon group-containing polymerizable unsaturated monomer with 8-22 carbon atoms having a branched structure and (e) an other polymerizable unsaturated monomer in a specific ratio. Also disclosed is a coating composition characterized by containing such a resin for coating material (A) and a specific aliphatic polyisocyanate compound (B).

Description

Specification

Hydroxyl-containing resin for paint and paint composition

Technical field

[0001] The present invention relates to a hydroxyl group-containing resin for paints and a paint composition.

Background art

[0002] Paints to be applied to an object to be coated such as an automobile body are required to have excellent coating performance such as acid resistance, scratch resistance, contamination resistance, and finishing power.

[0003] Conventionally, melamine cross-linked paints have been widely used as paints for the objects to be coated. Melamine cross-linked paint is a paint containing a hydroxyl group-containing resin and a melamine resin as a cross-linking agent, and has excellent coating film properties such as scratch resistance, finishing strength, high resilience, and the like. Yes. However, this paint has a problem that the acid resistance of the easily coated film is inferior because the melamine cross-linking bond is hydrolyzed by acid rain.

[0004] JP-A-6-220397 discloses a two-pack type urethane cross-linking coating composition comprising a hydroxyl group-containing acrylic resin, a hydroxyl group-containing oligoester and an isocyanate prepolymer. This paint has excellent acid resistance of the coating film because urethane crosslinks are hardly hydrolyzed. However, the scratch resistance of the coating film is insufficient.

Disclosure of the invention

Problems to be solved by the invention

[0005] An object of the present invention is to provide a coating composition capable of forming a cured coating film excellent in any of scratch resistance, acid resistance, stain resistance, finish, and the like.

Means for solving the problem

[0006] The present inventor has intensively studied to solve the above problems. As a result, alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 3 to 20 carbon atoms, styrene, hydroxyl group-containing polymerizable unsaturated monomer, and carbon atoms having 8 to 22 carbon atoms having a branched structure. A hydroxyl group-containing resin obtained by copolymerizing a monomer mixture containing a specific amount of a hydrogen group-containing polymerizable unsaturated monomer and the like, and a coating material containing a specific aliphatic polyisocyanate compound It has been found that the above object can be achieved by a composition. The present invention is based on such new knowledge. Based on this, it was completed.

[0007] The present invention provides the following hydroxyl group-containing resin for paints, and a paint composition containing the resin and a specific aliphatic polyisocyanate compound.

[0008] 1. (a) an alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 3 to 20 carbon atoms, (b) styrene, (c) a hydroxyl group-containing polymerizable unsaturated monomer, ( d) a mixture comprising a hydrocarbon group-containing polymerizable unsaturated monomer having a branched structure having 8 to 22 carbon atoms, and (e) another polymerizable unsaturated monomer, the total weight of which is Based on the content of monomer (a) 3-40% by weight, monomer (b) 3-40% by weight, monomer (c) 24-50% by weight The monomer (d) content is 3 to 40% by weight, the monomer (e) content is 0.:! To 41% by weight, the monomers ( _a ), (b) and (d ) Is a resin obtained by copolymerizing a monomer mixture having a total content of 35 to 70% by weight,

A hydroxyl group-containing resin for paints having a weight average molecular weight of 1,500 to 30,000 and a hydroxyl value of 120 to 180 mgKOH / g.

[0009] 2. Alicyclic hydrocarbon group in polymerizable unsaturated monomer (a) containing cycloaliphatic hydrocarbon group Force A bridged cycloaliphatic carbonization which is isobornyl group, tricyclodecanyl group or adamantyl group Item 2. The resin according to Item 1, which is a hydrogen group.

[0010] 3. The resin according to item 1, wherein the hydroxyl group-containing polymerizable unsaturated monomer (c) is a polymerizable unsaturated monomer having a hydroxyl group-containing hydrocarbon group having 4 to 20 carbon atoms.

[0011] 4. A hydrocarbon group-containing polymerizable unsaturated monomer (d) having 8 to 22 carbon atoms having a branched structure is represented by the general formula (1)

[0012] [Chemical 1]

[0013] (wherein X represents a hydrogen atom or a methyl group) two t-butyl groups in the molecule represented by Item 2. The resin according to Item 1, wherein the resin is a (meth) acrylic acid alkyl ester.

[0014] 5. The other polymerizable unsaturated monomer (e) is a linear or branched alkyl ester of (meth) acrylic acid having 1 to 7 carbon atoms, (meth) acrylic acid having 8 to 8 carbon atoms. Item 22. The above item 1, which is at least one monomer selected from the group consisting of 22 linear alkyl esters, acidic functional group-containing polymerizable unsaturated monomers, and epoxy group-containing polymerizable unsaturated monomers. Resin

[0015] 6. (A) The hydroxyl group-containing resin according to Item 1, and

(B) a reaction product of an aliphatic diisocyanate and a polyforce prolatatone polyol or polyether polyol having a number average molecular weight of 400 to 1,500, the isocyanate content is 5 to 15% by weight, and 3 to 9 A coating composition characterized by containing a functional aliphatic polyisocyanate baboon compound.

[0016] 7. The blending ratio of the aliphatic polyisocyanate compound (B) is the above hydroxyl group-containing resin (A

7. The coating composition according to item 6, wherein the amount of the isocyanate group of component (B) is 0.5 · 2.0 to 2.0 equivalents per equivalent of hydroxyl group.

[0017] 8. The coating composition according to item 6, further comprising (C) an acidic phosphate compound and / or an amine neutralized product thereof.

[0018] 9. The coating composition according to the above item 6, which is used for a top clear coat coating.

[0019] Hydroxyl-containing resin for paint (A)

The hydroxyl group-containing resin (A) for paint of the present invention comprises (a) an alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 3 to 20 carbon atoms, (b) styrene, (c) a hydroxyl group-containing polymerization. Specific polymerizable unsaturated monomer, (d) a hydrocarbon group-containing polymerizable unsaturated monomer having a branched structure having 8 to 22 carbon atoms, and (e) other polymerizable unsaturated monomer It is a resin obtained by copolymerizing a monomer mixture containing a ratio.

[0020] The hydroxyl group-containing resin (A) has a weight average molecular weight in the range of about 1,500 to 30,000, and a hydroxyl value in the range of about 120 to 180 mgKOHZg.

[0021] Further, the hydroxyl group-containing resin (A) is usually an acrylic monomer as at least one of the polymerizable unsaturated monomers (a), (b), (c), (d), and (e). It is an acrylic resin obtained using a monomer. [0022] Hereinafter, each polymerizable unsaturated monomer will be described more specifically.

[0023] In the present specification, "(meta) attalate" means "attalate or metatarate".

[0024] Polymerization containing alicyclic hydrocarbon soot having 3 to 20 carbon atoms' cochlear unsaturated monomer (a)

As the monomer (a), a bridged alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 10 to 20 carbon atoms, an alicyclic hydrocarbon group-containing polymerizable having 3 to 12 carbon atoms And unsaturated monomers.

The bridged alicyclic hydrocarbon group in the bridged alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 10 to 20 carbon atoms includes isobornyl group, tricyclodecanyl group and adamantyl. Examples include groups. Examples of the bridged alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 10 to 20 carbon atoms include, for example, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and adamantyl (meth) acrylate. 3, 5-dimethyladamantyl (meth) acrylate, 3-tetracyclododecinole (meth) acrylate, and the like.

[0026] Examples of the polymerizable unsaturated monomer having an alicyclic hydrocarbon group having 3 to 12 carbon atoms include cyclohexyl (meth) acrylate, 4-methylcyclohexylmethyl (meth) acrylate. , 4-ethyl cyclohexylmethyl (meth) acrylate, 4-methoxy cyclohexyl (meth) acrylate, t-butyl cyclohexyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclododecyl (meth) acrylate, tetrahydrofurfuryl Nore (meta) acrylate and the like.

[0027] By using the monomer (a) as a constituent monomer of the resin, the glass transition temperature (Tg) of the resulting resin increases and the polarity decreases. The effects of improving strength and improving water resistance and stain resistance of the coating film can be obtained.

[0028] The proportion of monomer (a) used is 3 based on the total weight of the monomer mixture consisting of monomers (a), (b), (c), (d) and (e). It is appropriate that the amount is about -40% by weight, preferably about 5-30% by weight. When the proportion of monomer (a) used is less than 3% by weight, the finish and water resistance tend to be reduced. On the other hand, when it exceeds 40% by weight, the hydroxyl group-containing polymerizable unsaturated monomer (c) and And the copolymerization reactivity of the monomer mixture tend to decrease. [0029] Styrene (b)

By using styrene (b) as the constituent monomer, the Tg of the resulting resin increases, and a hydrophobic film with a high refractive index can be obtained. The effect of improving the water resistance and the water resistance and acid resistance of the coating film is obtained.

[0030] The proportion of styrene (b) used is 3 to 3 based on the total weight of the monomer mixture consisting of the monomers (a), (b), (c), (d) and (e). It is appropriate that the amount is about 40% by weight, preferably about 5 to 30% by weight. When the proportion of styrene (b) used is less than ¾% by weight, the finish, water resistance, acid resistance, or gloss of the resulting coating film tends to decrease. Tend to decrease.

[0031] M ^^ ^ mn ¾ book (c)

Examples of the monomer (c) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) Examples include attalylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, force prolataton-modified hydroxyl group-containing (meth) acrylate, 4-methylol cyclohexyl (meth) acrylate. it can. Examples of commercially available products of force-prolataton-modified hydroxyl group-containing (meth) atalylate include “Platacel FM” (trade name, manufactured by Daicel Chemical Industries), etc. Examples thereof include “CHDMMA” (trade name, manufactured by Nippon Kasei Co., Ltd.).

[0032] As the monomer (c), a polymerizable unsaturated monomer having a hydroxyl group-containing hydrocarbon group having 4 to 20 carbon atoms, specifically, 4-hydroxybutyl (meth) acrylate. It is preferable to use 4_methylolcyclohexyl acrylate.

[0033] The hydroxyl group based on the monomer (c) functions as a crosslinkable functional group of the resulting copolymer resin.

[0034] The proportion of monomer (c) used is based on the total weight of the monomer mixture consisting of monomers (a), (b), (c), (d) and (e). It is appropriate that the amount is about -50% by weight, preferably about 30-45% by weight. When the proportion of the monomer (c) used is less than 24% by weight, the resulting cured coating film is insufficiently cross-linked and tends to reduce the scratch resistance. The compatibility with the body (a) and the copolymerizability of the monomer mixture decreased, and the resulting copolymer weight There is a tendency that the compatibility between the polymer (A) and the polyisocyanate compound (B) is lowered, and the gloss of the coating film is lowered.

[0035] Unsaturated single-most polymer containing hydrocarbon soot having 8 to 22 carbon atoms and having a structure (d)

Polymerizable unsaturated monomer having a branched hydrocarbon structure having 8 or more carbon atoms

Examples of (d) include 2_ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isomyristyl (meth) acrylate, general formula (1)

[0036] [Chemical 2] CH ₃ CH ₃

CH ₂ = C CH ₂ CH ₂ -CH-CH ₂ -C-CH ₃

COO-CH ₂ CH CH _¾ ^CH 3 ( ¹⁾

I I "

CH-CH2-C-CH3

Hg CH3

[0037] (In the formula, X represents a hydrogen atom or a methyl group.) (Meth) acrylic acid alkyl ester represented by As a commercial product of the compound represented by the general formula (1), for example, “isostearyl acrylate” (trade name, manufactured by Osaka Organic Chemical Industry Co., Ltd., a compound in which X is a hydrogen atom in the general formula (1)) Can give.

[0038] By using the monomer (d) as a constituent monomer component of the resin, the Tg and polarity of the resulting resin are lowered. As a result of improving the finish by smoothing the surface, and having a branched hydrocarbon group, the effect of improving the acid resistance and adhesion of the coating film compared to the case of having a straight chain hydrocarbon group can be obtained. Obtainable. In particular, by using the compound represented by the general formula (1) as a constituent monomer component of the resin, it is possible to obtain a coating film remarkably excellent in both acid resistance and scratch resistance.

[0039] The proportion of monomer (d) used is based on the total weight of the monomer mixture consisting of monomers (a), (b), (c), (d) and (e). It is suitable that it is about 3 to 40% by weight, preferably about 8 to 35% by weight. When the proportion of monomer (d) used is less than ¾% by weight, the resulting copolymer (A) has a higher polarity and the compatibility with the polyisocyanate compound (B) tends to decrease. There As a result, the wettability to the object to be coated may be reduced. On the other hand, if it exceeds 40% by weight, the adhesion of the coating film tends to decrease.

[0040] Other polymerizable unsaturated monomer (e)

The monomer (e) is a monomer other than the monomers (a), (b), (c) and (d) and is a copolymerizable monomer, It can be selected and used as appropriate in consideration of various characteristics of coalescence. As the monomer (e), for example, (meth) acrylic acid having a carbon number:! To 7 linear or branched alkyl ester, (meth) acrylic acid having a carbon number of 8 to 22 carbon alkyl ester An acidic functional group-containing polymerizable unsaturated monomer, an epoxy group-containing polymerizable unsaturated monomer, a nitrogen-containing polymerizable unsaturated monomer, a halogen-containing polymerizable unsaturated monomer, a vinyl ester, a vinyl ether, Examples thereof include unsaturated cyanide compounds. These can be used alone or in combination of two or more.

[0041] As the monomer (e), (meth) acrylic acid linear or branched alkyl ester having 1 to 7 carbon atoms, (meth) acrylic acid linear alkyl ester having 8 to 22 carbon atoms It is preferable to use at least one monomer selected from the group consisting of an acidic functional group-containing polymerizable unsaturated monomer and an epoxy group-containing polymerizable unsaturated monomer.

[0042] Examples of the linear or branched alkyl ester having 1 to 7 carbon atoms of (meth) acrylic acid include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, Examples thereof include isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate and t_butyl (meth) acrylate.

[0043] Examples of the linear alkyl ester of (meth) acrylic acid having 8 to 22 carbon atoms include lauryl (meth) acrylate and stearyl (meth) acrylate.

[0044] Examples of the epoxy group-containing polymerizable unsaturated monomer include glycidyl (meth) atrelate.

[0045] Examples of the nitrogen-containing polymerizable unsaturated monomer include (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, butyl pyridine, butyl imidazole and the like. Examples of the halogen-containing polymerizable unsaturated monomer include butyl chloride and vinylidene chloride. Examples of the bull ester include bull acetate. Examples of vinyl ether include divinyl ether. Can be mentioned. Examples of unsaturated cyanide compounds include (meth) acrylonitrile.

[0046] Examples of the acidic functional group-containing polymerizable unsaturated monomer include carboxyl group-containing unsaturated monomers such as (meth) acrylic acid, crotonic acid, itaconic acid, maleic acid, and maleic anhydride; Acid, sulfonic acid group-containing unsaturated monomers such as sulfoethyl (meth) acrylate; 2— (meth) acryloyloxychetyl acid phosphate, 2- (meth) acryloyloxypropyl acid phosphate, 2- Examples thereof include acidic phosphate ester unsaturated monomers such as (meth) ataryloxyloxypropylate, 2- (meth) atyloxyxetylphenyl phosphate, and the like.

[0047] The proportion of monomer (e) used is 0 based on the total weight of the monomer mixture consisting of monomers (a), (b), (c), (d) and (e). It is appropriate that it is about 41 to 41% by weight, preferably about 0.5 to 30% by weight.

[0048] Among the monomers (e), acidic functional group-containing polymerization such as carboxyl group-containing unsaturated monomer, sulfonic acid group-containing unsaturated monomer, and acidic phosphate ester unsaturated monomer. The unsaturated unsaturated monomer can act as an internal catalyst when the obtained hydroxyl group-containing resin undergoes a crosslinking reaction with the polyisocyanate compound, and the amount used is a monomer constituting the resin. Based on the total amount of the mixture, it is preferable to use within the range of about 0.:! To 5% by weight, and more preferably within the range of about 0.5 to 3% by weight.

[0049] Further, in the monomer mixture composed of the monomers (a), (b), (c), (d) and (e), both the acid resistance and the scratch resistance of the coating film From the viewpoint of obtaining an extremely excellent resin, the total weight of the monomers (a), (b) and (d) is about 35 to 70% by weight, preferably 40 to 40% based on the total weight of the monomer mixture. It is appropriate that it is in the range of about 65% by weight.

[0050] The copolymerization method for copolymerizing the monomer mixture to obtain the resin (A) is not particularly limited, and a known copolymerization method can be used. In particular, it is preferable to use a solution polymerization method in which polymerization is performed in an organic solvent in the presence of a polymerization initiator.

[0051] Examples of the organic solvent used in the solution polymerization method include aromatic solvents such as toluene, xylene, and high-boiling aromatic hydrocarbons; ethyl acetate, 3-methoxybutyl acetate, ethylene glycol ethyl Ether acetate, propylene glycol methyl Examples include ester solvents such as ether acetate; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, and methyl amyl ketone; propyl propionate, butyl propionate, and ethoxyethyl propionate. Examples of commercially available high-boiling aromatic hydrocarbons include “Suzo Zonole 1000” (trade name, manufactured by Cosmo Oil Co., Ltd., high-boiling petroleum solvent).

[0052] These organic solvents may be used alone or in combination of two or more.

In particular, as the organic solvent, since the resin (A) has a high hydroxyl value, it is preferable to use an ester solvent or a ketone solvent having a high boiling point from the viewpoint of the solubility of the resin. Furthermore, a high boiling point aromatic solvent can also be used in combination.

[0053] Examples of the polymerization initiator that can be used in the copolymerization of the resin (A) include 2,2'-azobisisobutyronitrile, benzoyl peroxide, 2,2-di (tamylamylper). Oxy) List known radical polymerization initiators such as butane, di-t-butyl peroxide, di-t-amyl peroxide, t-butyl bactate, 2,2'-azobis (2-methylbutyronitrile) Can do.

The resin (A) has a weight average molecular weight in the range of about 1,500 to 30,000, preferably in the range of about 3,000 to 20,000, such as finish, acid resistance and weather resistance. It is suitable because of its excellent coating performance. Resin (A) has a hydroxyl value of about 120 to 180 mgKOH / g, preferably within the range of about 130 to 170111 _§ 1 ^ 〇 ^^ / _§, so that the resulting coating composition has curability. Excellent, cross-linking density of the coating film is high, suitable from the point.

[0055] The resin (A) has a glass transition temperature (Tg) of about _45 ° C to + 10 ° C, particularly _32 ° C to

It is preferable that the temperature is within a range of about _1 ° C. from the viewpoint of excellent coating performance of both acid resistance and scratch resistance.

[0056] In the present specification, the weight average molecular weight is a value obtained by converting the weight average molecular weight measured by gel permeation chromatograph on the basis of the weight average molecular weight of polystyrene.

[0057] Coating composition

The coating composition of the present invention is a composition obtained by blending a specific aliphatic polyisocyanate compound (B) with the hydroxyl group-containing resin (A). [0058] Aliphatic polyisocyanate compound (B)

In the coating composition of the present invention, the aliphatic polyisocyanate compound (B) used as a crosslinking agent for the hydroxyl group-containing resin (A) is an aliphatic diisocyanate and a polyisocyanate having a number average molecular weight of 400 to 1,500. It is an aliphatic polyisocyanate compound which is a reaction product with a strong prolatatone polyol or a polyether polyol and has an isocyanate content of 5 to 15% by weight and is 3 to 9 functional.

[0059] In this aliphatic polyisocyanate compound, 3 to 9 isocyanate groups are bonded to a poly-force protatone polyol or a polyether polyol via a urethane bond, and molecules of these isocyanate groups are included. The cured coating film formed by the coating composition of the present invention has excellent elasticity due to the fact that the bonding positions in the composition are separated from each other and the crosslinking bond with the hydroxyl group-containing resin (A) is a urethane bond. Can be granted. Therefore, even if the cured coating film is scratched on the basis of its excellent elasticity, an effect of excellent scratch resistance can be obtained by having excellent recoverability of the scratch.

[0060] The aliphatic polyisocyanate (B) in the coating composition of the present invention is an isocyanate from the viewpoint of imparting a sufficiently high elasticity to the cured coating film of the composition and improving the scratch resistance. The content is 5 to 15% by weight, and 3 to 9 functional ones are used. As the aliphatic polyisocyanate (B), those having an isocyanate content of about 7 to 12% by weight and having 3 to 9 functions are preferable.

[0061] The isocyanate content in the present specification is defined by the following formula.

[0062] Isoshianeto content (wt ^{_{0/0) = [(42}} X n) / M] X 100

In the formula, 42 represents the molecular weight of the isocyanate group (NC 0). n represents the number of isocyanate groups. M represents the molecular weight of the aliphatic polyisocyanate compound.

[0064] As is clear from the above definition, in the aliphatic polyisocyanate compound having an isocyanate content of 5 to 15% by weight used in the present invention, the lower the content within this range, the more the poly If the molecular weight of the portion based on prolataton polyol or polyether polyol is large, it will be unsatisfactory.

[0065] Examples of the raw material aliphatic diisocyanate include tetramethylene diisocyanate, Examples include range isocyanate and lysine diisocyanate.

[0066] As a raw material poly-strength prolataton polyol, for example, it can be obtained by ring-opening polymerization of a force pro-latatone such as ε-strength pro-latatone in the presence of a catalyst using a tri- to 9-valent alcohol as an initiator. Examples thereof include compounds such as poly-force prolatathon triol. Examples of the trivalent to 9-valent alcohol as the initiator include trimethylolpropane, glycerin, pentaerythritol, dipentaerythritol and the like. As the catalyst, for example, an organic titanium compound, an organic tin compound, or the like can be used.

[0067] The ring-opening polymerization of force prolatatone is carried out, for example, in a nitrogen gas atmosphere by using force prolatatone and the above initiator so that the number average molecular weight force of the resulting poly force prolatatone polyol is about 00 to 1,500. The ratio is set, and the catalyst is further added to the strength of prolatatone at a concentration of about 0.:! To lOOppm, and the reaction is carried out at a temperature of about 150 ° C to 200 ° C for about 4 to 10 hours. You can do the power S.

[0068] Commercially available products can be used as the poly-strength prolatatone polyol. Examples of commercially available products include “Plaxenore 305”, “Platacel 308”, “Platacel 205” and the like (trade names, all manufactured by Daicel Chemical Industries, Ltd.).

[0069] In addition, as the raw material polyether polyol, for example, a polymer diol compound such as polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, and the like, a tri- to 9-valent alcohol, and the presence of a catalyst are used. Below, compounds such as polyether triol obtained by etherification reaction can be mentioned. The number average molecular weight of the polyether polyol is adjusted to about 400 to about 1,500. As trivalent to 9-valent alcohols and catalysts, those used in the production of poly-strength prolataton polyol can be used.

[0070] The reaction of the aliphatic diisocyanate with the poly-strength prolataton polyol or the polyether polyol can be carried out according to a conventional method. The reaction can be carried out at a temperature in the range from room temperature to about 200 ° C, preferably in the range from about 80 to about 160 ° C.

[0071] After completion of the reaction, it is preferable to recover unreacted aliphatic diisocyanate in the reaction mixture by solvent extraction or the like.

[0072] The component (B) may be used alone or in combination of two or more. it can.

[0073] The isocyanate group in the aliphatic polyisocyanate compound (B) may be free or blocked.

[0074] The block of the free / f sulfonate group of the aliphatic polyisocyanate compound (B) is facilitated by mixing the polyisocyanate compound (B) and the blocking agent. I can do it.

[0075] Examples of the blocking agent include phenolic blocking agents such as phenol, cresol, and xylenol; _ε -force prolatatam, δ-valerolatatam, γ-butalatatatam, βpropiolatam and other ratatamum blocking agents; methanol, Ethanol, η-propylanolol, i-propinoreanolol, n-butinoreanolol, i-butinoleanolol, t-butyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether , Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, benzyl alcohol, and other alcoholic block copolymers IJ; formamide , Acetonoredoxime, acetoxime, methinorethinoreketoxime, dicetinoremonooxime, benzophenone oxime, cyclohexanoxime, etc. Blocking agents such as active methylene-based blocking agents such as methyl and acetylacetone can be used

[0076] As the aliphatic polyisocyanate compound (B), a commercially available product can be used.

Examples of commercially available products include “Deyuranate E_402_90T” (trade name, manufactured by Asahi Kasei Corporation, trifunctional, isocyanate content 9.4% by weight, number average molecular weight 1,400, non-block), “Deyuranate E_405 _ 80T "(trade name, manufactured by Asahi Kasei Co., Ltd., trifunctional, isocyanate content 8.9% by weight, number average molecular weight 1,400, non-block)," deyuranate ME20_100 "(trade name, manufactured by Asahi Kasei Corporation, (Non-functional, isocyanate content 8.5% by weight, number average molecular weight 1,900, non-block)) (all are trade names, manufactured by Asahi Kasei Co., Ltd.).

[0077] The blending ratio of the aliphatic polyisocyanate compound (B) in the coating composition of the present invention is such that the isocyanate group of the component (B) is 0 per equivalent of hydroxyl group of the hydroxyl group-containing resin (A). Five~ An amount of about 2.0 equivalents, particularly about 0.7 to about 1.5 equivalents, is preferable because both the acid resistance and scratch resistance of the resulting coating film are excellent.

[0078] Acid phosphate ester compound and / or neutralized amine thereof (C)

In the coating composition of the present invention, for the purpose of further improving the scratch resistance, in addition to the above components (A) and (B), an acidic phosphate ester compound and Z or an amine neutralized product thereof as necessary. Can contain (C).

[0079] The component (C) acts as a curing catalyst for the urethane crosslinking reaction between the hydroxyl group-containing resin (A) and the aliphatic polyisocyanate compound (B).

[0080] The acidic phosphoric acid ester compound is an organic acidic compound obtained by substituting a part of hydrogen of an inorganic phosphorus compound such as phosphoric acid, a condensate thereof, phosphorous acid or a condensate thereof with an alkyl group or an aryl group. It is a (sub) phosphate ester. The alkyl group may be either linear or branched, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl. , T-butyl, n-pentyl, n-hexyl, n-heptyl, 2-ethylhexyl, n-decyl and the like.

[0081] Specific examples of the acidic phosphate compound include, for example, methyl acid phosphate, dimethyl acid phosphate, ethyl acid phosphate, jetyl acid phosphate, monopropyl acid phosphate, isopropyl acid phosphate, dip Pyracid phosphate, monobutyl acid phosphate, dibutyl acid phosphate, mono-2_ethyl hexyl acid phosphate, di_2_ethyl hexyl acid phosphate, isodecyl acid phosphate, tridecyl acid phosphate, lauryl acid phosphate, stearyl acid Such as phosphate, isostearyl acid phosphate, oleyl acid phosphate, monophenyl acid phosphate, etc. It can force S.

[0082] Among the above, those having an alkyl group having 3 to 4 carbon atoms such as monopropyl acid phosphate and monobutyl acid phosphate are excellent in the curability of the coating composition and ensure a sufficient pot life. Therefore, it can be preferably used.

[0083] As the above acidic phosphate ester compound, one neutralized with an amine compound can be used as necessary from the viewpoint of securing a sufficient pot life. [0084] As such an amine compound, any of primary, secondary and tertiary amine compounds such as ammonia, diisopropylamine, triethylamine, and tripropylamine can be used. In particular, tertiary amine compounds such as triethinoreamine and 1,8-diazabicyclo [5,4,0] unde force_7-en can be used more suitably.

[0085] The component (C) can be used alone or in combination of two or more.

[0086] When the acidic phosphate compound and Z or its amine neutralized product (C) are used, the amount used is 100 parts by weight of the total solid content of the component (A) and the component (B). About 0.5 to 5 parts by weight is preferred, about 3 to 3 parts by weight is more preferred, and about 0.5 to 2 parts by weight is more preferred.

[0087] Other ingredients

The coating composition of the present invention comprises a hydroxyl group-containing resin (A), an aliphatic polyisocyanate compound (B) and an optional acidic phosphate ester compound and / or an amine neutralized product (C) thereof, Furthermore, it can contain additives for coatings such as curing catalysts other than component (C), pigments, pigment dispersants, leveling agents, ultraviolet absorbers, light stabilizers, and plasticizers as necessary.

[0088] Examples of the curing catalyst include, for example, tin octylate, dibutyltin di (2-ethylhexanoate), dioctyltin di (2_ethylhexanoate), dioctyltin diacetate, dibutyltin dilaurate, Examples thereof include organometallic catalysts such as dibutyltin oxide, dioctyltin oxide and lead 2-ethylhexanoate, and tertiary amines. These compounds may be used alone or as a mixture of two or more.

[0089] The amount of the curing catalyst used varies depending on the type, but is usually about 0.05 to 5 parts by weight with respect to 100 parts by weight of the total solid content of the components (A) and (B).

[0090] Examples of the pigment include titanium oxide, zinc white, carbon black, cadmium red, molybdenum red, chrome yellow, chromium oxide, Prussian blue, cobalt blue, azo pigment, phthalocyanine pigment, quinacridone pigment, isoindoline pigment, Colored pigments such as selenium pigments and perylene pigments; extender pigments such as talc, clay, kaolin, Norita, barium sulfate, barium carbonate, calcium carbonate, silica, alumina white; aluminum powder, clouds Examples thereof include metallic pigments such as mother powder and mica powder coated with titanium oxide.

[0091] As the UV absorber, known ones can be used, and examples thereof include benzotriazole-based absorbers, triazine-based absorbers, salicylic acid derivative-based absorbers, and benzophenone-based absorbers.

[0092] The content of the ultraviolet absorber in the coating composition is usually about 0 to 10 parts by weight with respect to 100 parts by weight of the total solid content of the components (A) and (B). Is preferred from the viewpoint of excellent weather resistance and yellowing resistance of the coating film. The content of the ultraviolet absorber is more preferably about 0.2 to 5 parts by weight, and more preferably about 0.3 to 2 parts by weight.

[0093] Conventionally known light stabilizers can be used, and examples thereof include hindered amine light stabilizers.

[0094] The content of the light stabilizer in the coating composition is usually about 0 to 10 parts by weight with respect to 100 parts by weight of the total solid content of the components (A) and (B). However, it is preferable from the viewpoint of excellent weather resistance and yellowing resistance of the coating film. The content of the light stabilizer is more preferably about 0.2 to 5 parts by weight, and more preferably about 0.3 to 2 parts by weight.

[0095] Preparation of coating composition

The coating composition of the present invention is usually an organic solvent-type coating. For example, the component (A), the component (B), and, if necessary, the component (C) and other components are contained in the organic solvent. Can be easily prepared.

[0096] When the resin component or the like is a solution or dispersion of an organic solvent, the organic solvent in the paint may not be added, or may be added for the purpose of adjusting the solid content.

[0097] Examples of the organic solvent include aromatic hydrocarbon solvents such as toluene, xylene, and high-boiling aromatic hydrocarbons; n-hexane, n-heptane, n-octane, n-decane, n- Aliphatic hydrocarbon solvents such as dodecane, cyclopentane, cyclohexane, etc .; Ketone solvents such as acetone, methylolethyl ketone, methylisobutylketone, diisobutylketone, methylaminoleketone; ethyl acetate, n-butyl acetate Ester solvents such as isobutyl acetate; Alcohol solvents such as ethyl alcohol, propyl alcohol, butyl alcohol; Ethylene glycol, diethylene glycol, propylene glycol, hexylene glycol Glycol solvents such as Nole; known solvents such as glycol ether solvents such as methyl ether, ethyl acetate, propinoate ethere, butinoreethenole, and glycolic alcoholate solvents such as propionate. Can be used.

[0098] When the isocyanate group of the component (B) is not blocked, the coating composition of the present invention usually contains a coating base containing the hydroxyl group-containing resin (A) and other components and an aliphatic polyisoisocyanate. It is a two-component paint that is separated from the cross-linking agent containing the cyanate compound (B), and both are mixed and used immediately before use. The pot life after mixing is usually about 2 to 12 hours.

[0099] On the other hand, when the isocyanate group of the component (B) is blocked, the coating composition of the present invention usually contains a hydroxyl group-containing resin (A), an aliphatic polyisocyanate compound ( This is a one-component paint containing B) and other components.

[0100] 'Coating method of coating composition

The material to which the coating composition of the present invention is applied is not particularly limited, but for example, it is preferably the body of various vehicles such as automobiles and motorcycles. Also, cold-rolled steel sheets, zinc-plated steel sheets, zinc alloy-plated steel sheets, stainless steel sheets, tin-plated steel sheets, etc., metal base materials such as aluminum plates, aluminum alloy plates, and various plastic materials Good.

[0101] Further, the object to be coated may be one in which the metal surface of the vehicle body or the metal substrate is subjected to a surface treatment such as a phosphate treatment, a chromate treatment, or a complex oxide treatment. . Furthermore, the coated object may be one in which an undercoating film such as various electrodeposition paints and Z or an intermediate coating film are formed on the above-mentioned vehicle body, metal base material, or the like.

[0102] The coating method of the coating composition of the present invention is not particularly limited. For example, a wet coating film can be formed by a coating method such as air spray coating, airless spray coating, rotary atomization coating, or curtain coat coating. it can. These coating methods can be electrostatically stamped if necessary. Among these, air spray coating is particularly preferable. Usually, the coating amount is preferably an amount of about 10 to 50 zm as a cured film thickness.

[0103] In addition, in the case of air spray coating, airless spray coating and rotary atomization coating, the viscosity of the coating composition is adjusted to a viscosity range suitable for the coating, usually Ford Cup # No. 4 viscosity. It is preferable to use an organic solvent or the like so that the viscosity is within a viscosity range of about 15 to 60 seconds at 20 ° C.

[0104] Curing of a wet coating film obtained by applying a coating composition to an object to be coated can be performed by heating. The heating can be performed by a known heating means, for example, a hot air furnace, an electric furnace

A drying furnace such as an infrared induction heating furnace can be applied. The heating temperature is suitably in the range of 60 to: 180 ° C, preferably 90 to 150 ° C. The heating time is not particularly limited but is preferably in the range of 15 to 30 minutes.

[0105] The coating composition of the present invention is useful as a coating for automobile bodies, and can form a coating film excellent in both scratch resistance and acid resistance, and thus is particularly suitable for an overcoat clear coat coating.

[0106] When used as a clear coat paint, for example, after applying a colored base coat paint on an object to be coated, a step of heat-curing as necessary, and a paint of the present invention as a clear coat paint on the base coat film A top coat film consisting of two layers can be formed by a two-coat two-beta method or a two-coat one-beta method.

[0107] In addition, for example, a step of heating and curing the first colored base coat on the object to be coated, if necessary, after coating, a second colored base coat paint on the first base coat coating film, and so on. Including the process of heat curing according to the above, including the process of applying the invention paint as a clear coat paint on the second base coat film, followed by heat curing 3 coat 3 beta method, 3 coat 2 beta method or 3 coat 1 beta method Depending on the method, the ability to form a three-layer topcoat can be achieved.

[0108] As the colored base coat paint, a conventionally known normal thermosetting base coat paint can be used. Specifically, a base resin such as an acrylic resin, a polyester resin, an alkyd resin, or a urethane resin having a crosslinkable functional group: a crosslinking agent such as an amino resin, a polyisocyanate compound, or a block polyisocyanate compound; In addition, a paint containing a metallic pigment or the like can be used.

[0109] In addition, as a base coat paint, from the viewpoint of environmental problems, resource saving, etc., it is possible to use a low-use amount of an organic solvent, a high solid organic solvent-type paint, an aqueous paint or a powder paint. preferable.

The invention's effect

[0110] According to the coating composition of the present invention containing a specific hydroxyl group-containing resin and a specific aliphatic polyisocyanate compound, curing excellent in all of scratch resistance, acid resistance, stain resistance, finish, etc. The remarkable effect that a coating film can be formed is acquired.

[0111] Accordingly, the coating composition of the present invention is extremely useful as a top coating for an article to be coated such as an automobile body.

BEST MODE FOR CARRYING OUT THE INVENTION

[0112] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited by these. In each example, “part” and “%” indicate “weight part” and “wt%”, and the film thickness of the coating film is based on the cured coating film.

[0113] The average molecular weight in each example is the average molecular weight measured with a gel permeation chromatograph (trade name “HLC8120GPC”, manufactured by Tosoichi Co., Ltd.), based on the average molecular weight of polystyrene. It is a converted value. Columns include “TSKgel G—4000H XL”, “T SKgel G—3000H XL”, “TSKgel G—2500H XL”, “TSKgel G—2000H X Lj (trade names, all manufactured by Tosoh Corporation). The measurement was carried out under the conditions of mobile phase; tetrahydrofuran, measurement temperature: 40 ° C, flow rate: lcc / min, detector; RI.

[0114] Examples:! To 13 and comparative examples:! To 6: Production of hydroxyl group-containing resin for paint

[0115] A tetralo flask equipped with a stirrer, a thermometer, a condenser tube, and a nitrogen gas inlet was charged with 31 parts of ethoxyethyl propionate and heated to 155 ° C under nitrogen gas flow. After reaching 155 ° C, the nitrogen gas flow was stopped and the monomers (100 parts in total) having the composition shown in Table 1 below and 2,2-di (t-amyl peroxy) as the polymerization initiator were used. A monomer mixture with butane was added dropwise over 4 hours. After aging for 2 hours while ventilating nitrogen gas at 155 ° C, the solution was cooled to 100 ° C and diluted with 32.5 parts of butyl acetate to obtain each hydroxyl group-containing resin solution having a solid content of 60%. It was.

[0116] The glass transition temperature (° C) of each hydroxyl group-containing resin obtained was calculated by the following formulas (I) and (及び).

[0117] 1 / Tg (K) = (W / T) + (W / τ) + (I) [0118] Tg (° C) = Tg (K) -273 (II)

[0119] In the formula (I), W, W, ··· are the respective weight fractions of the monomers used for the copolymerization, T

1 2 ¹

T, ··· represent Tg (K) of the homopolymer of each monomer. Τ, T, ··· is 、

2 ¹

olymer Handbook (Second Edition, J. Brandup-E. H. Immergut edited by fc.

[0120] In Table 1, the composition (parts) of each unsaturated monomer mixture of Examples:! To 13 and Comparative Examples:! To 6 and the weight-average molecular weight, hydroxyl value, and glass transition of each resin obtained Indicates temperature (° C)

[0121] [Table 1]

table 1

[0122] [Table 2] Example 8 9 1 0 1 1 1 2 1 3 Styrene 20 38 20 20 20 20 Isophoryl acrylate

Cyclohexyl methacrylate 28 5 5 6. 5 8 8

“Istestearyl acrylate” 9 7 25 25 25 Single 2-ethyl Λ-xyl acrylate 7 32 14 10 10 Sat 2-ethyl hexyl methacrylate

Body n-Butylacrylate

n-Fill Methylacrylate

α 4-Human 'Roxif' tyrylacrylate 42 42 42 36 36 Product 2 -Human 'D Quichetil 7 acrylate 34

2-hydroxy I til methacrylate

Acrylic acid 1 1 1 1 1

2-Methacrylyloxy I chilly 0.5

Dorfosfeet

2, 2-Shi '(卜 Ami-Talented 3 3 3 3 6 1. 45 Shi) Butane

匱 Average molecular weight 13200 16000 14000 14300 8600 20500 Hydroxyl value ngKOH / g) 164 164 164 164 140 140 Glass transition temperature (° C) -1. 1 -4. 8 -31. 2 -13. 7 -11. 5 -11 . 5 3]

Comparative example 1 2 3 4 5 6

Styrene 30 20 5 20 20 'Noho' Lunil Acrylate 30

Siku D-hexyl methacrylate 10 5 20

"Ilystearyl acrylate"

Single 2-engine hexyl acrylate 5 29 20 Amount 2-ethyl hexyl methacrylate 10 25

Body n-7 'Tiruak' route 25 10

n-Furyl methacrylate 43 46 14 Mouth 4-Human 'Roxyf' Tylacrylate 36 25 Product 2-Hydoxyl I Tyracrylate 34 34 34

2-Human 'D-xy I til methacrylate 45

Acrylic acid 1 1 1 1 1

2-methacryl Diloxy I

To Phosphate

2, 2- (t-amyl Λ o 3 3 3 3 3 3 shi)

Heavy molecular weight 13500 13000 13100 12500 13500 14000 Hydroxyl value OngKOH / g) 164 140 164 164 194 97 Glass transition temperature) -19. 8 -4. 2 -13. 1 -1 1. 4 +21. 1 -3 . 7

[0124] In Table 1, “Istestearyl Atarylate” (trade name, manufactured by Osaka Organic Chemical Industry Co., Ltd.) is

In the general formula (1), X represents a hydrogen atom.

[0125] Examples 14 to 28 and Comparative Examples 7 to 16: Production of coating composition

[0126] The hydroxyl group-containing resins, polyisocyanate compounds that are crosslinking agents, ultraviolet absorbers, and light stabilizers obtained in the above Examples:! To 13 and Comparative Examples:! Each coating composition was obtained by mixing with stirring using a disperser. Each coating composition is a two-pack type of a coating base obtained by mixing components other than the polyisocyanate compound and an isocyanate compound, and is used after mixing immediately before use.

[0127] The blending ratio of the polyisocyanate compound corresponds to the amount of 1 equivalent of the isocyanate group of the compound per 1 equivalent of hydroxyl group of the hydroxyl group-containing resin.

[0128] Table 2 shows the composition of each coating composition.

[0129] [Table 4] Table 2

[0130] [Table 5]

Table 2 (continued)

[0131] [Table 6]

Table 2 (continued)

[0132] The blending amount of each component shown in Table 2 is indicated by solid content (parts). In addition, the polyisocyanate in Table 2 The cyanate compounds G) to (iv), the ultraviolet absorber and the light stabilizer are as follows.

[0133] Polyisocyanate compound (i): Product name “Deyuranate E_402_90T”, manufactured by Asahi Kasei Corporation

, Trifunctional aliphatic polyisocyanate compound, solid content 90. / o, isocyanate content 9.4

%, Number average molecular weight 1,400, non-blocking.

[0134] Polyisocyanate compound (ii): Trade name "Deyuranate ME20-100", manufactured by Asahi Kasei Corporation,

9 Functional aliphatic polyisocyanate compound, solid content 100%, isocyanate content 8.5

%, Number average molecular weight 1,900, non-blocking.

[0135] Polyisocyanate compound (iii): Trade name "Takenate D160N", Takeda Pharmaceutical Co., Ltd., hexamethylene diisoisocyanate and trimethylolpropane adduct, solid content 75%

, Isocyanate content 16.8%, number average molecular weight 920, non-block.

[0136] Polyisocyanate compound (iv): Trade name "Takenate D140N", Takeda Pharmaceutical Co., Ltd., Isophorone diisoisocyanate and trimethylolpropane adduct, solid content 75%, isocyanate content 14 0%, number average molecular weight 980, non-blocking.

[0137] Ultraviolet absorber: Trade name “UV1164”, manufactured by Ciba Geigy Co., Ltd., benzotriazole-based ultraviolet absorber.

[0138] Light stabilizer: trade name “HALS292”, manufactured by Ciba Geigy Co., Ltd., a hindered amine light stabilizer.

[0139] Coating performance test

Examples 14-28 and Comparative Examples 7-: With respect to each coating composition obtained in 16, the coating film performance was examined according to the following method.

[0140] (1) Preparation of article to be coated

A thermosetting epoxy resin-based cationic electrodeposition paint (trade name “Electron 9600”, manufactured by Kansai Paint Co., Ltd.) is applied to a 0.8 mm thick dull steel sheet that has been subjected to zinc phosphate conversion treatment. Electrodeposition was applied to 20 xm and cured by heating at 170 ° C for 30 minutes. Next, a polyester resin 'melamine resin-based intermediate coating for automobiles (trade name “Amirak TP _ 65 _2”, manufactured by Kansai Paint Co., Ltd.) has a film thickness of 35 μm on the electrodeposition film. As described above, air spray coating was performed, and heat curing was performed at 140 ° C. for 30 minutes to obtain an object to be coated. [0141] (2) Each coating composition was diluted with butyl acetate and adjusted to a viscosity of 22 seconds at 20 ° C using Ford Cup # 4. This viscosity-adjusted paint is air spray-coated on the above-mentioned substrate so as to have a film thickness of 40 xm, baked at 140 ° C for 30 minutes, and then allowed to stand at room temperature for 7 days to prepare a test coating plate. Obtained. About each obtained coating plate for a test, the coating-film performance test of scratch resistance, acid resistance, and stain resistance was performed by the following method.

[0142] Scratch resistance: A dye fastness friction tester (trade name “FR_II”, manufactured by Suga Test Instruments Co., Ltd.) was used as a scratch resistance tester. Polishing powder (trade name “Dalmac Cleanser”, manufactured by Dalmacren The One Honpo Co., Ltd.) 3 g was mixed at a rate of 2 g of water to obtain an abrasive. About 3 drops of this abrasive was adhered to the nell, the nell was pressed with a test machine terminal, a 500 g load was applied, and the coating surface of each coated plate was rubbed back and forth 30 times. Then, the coated surface is washed with running water, air-dried, and the 20-degree specular reflectance (20 ° G value) of the coated surface is measured, and the gloss retention (%) against the 20 ° G value before the test. It was evaluated by. The higher the gloss retention, the better the scratch resistance.

[0143] Acid resistance: lmg / g NaNO aqueous solution 112.2 g, lmg / g KNO aqueous solution 29.8 g, 1

3 3

mg / g CaCl 20.77 solution 21.2 g, lmg / g MgSO 70.7 solution 46.9 g,

2 2 4 2

lmg / g (NH 3) SO solution 419.6 g, 0. IN H 2 SO solution 171.7 g, 0. IN

4 2 4 2 4

HNO aqueous solution 14.5 g, 0.05N HC1 aqueous solution 57.2 g and lmg / g NaF aqueous solution

Three

The liquid 26.9g was mixed and the pH was adjusted to 1.0 with H 2 SO to obtain artificial acid rain.

twenty four

[0144] 0.4 cc of this acid rain was dropped on the coating film of each test coating plate, heated on a hot plate heated to 60 ° C for 15 minutes, washed with water, and the coated surface was visually observed. The acid resistance was evaluated according to the following criteria.

[0145] A: No change in the coating surface and excellent acid resistance, B: No whitening or blistering on the coating surface, but a step is observed at the boundary of the acid rain drop, and the acid resistance is slightly inferior , C: Whitening or blistering is observed on the coated surface and the acid resistance is poor.

[0146] In addition, using a surface roughness meter (trade name “Surfcom 570A”, manufactured by Tokyo Seimitsu Co., Ltd., surface roughness shape measuring machine), a cutoff of 0.8 mm (running speed of 0.3 mm / sec) was used. The etching depth (zm) of the coating film at the acid rain dripping point was measured under the condition of 5,000 times magnification. The smaller the etching depth, the better the acid resistance. [0147] Contamination resistance: Each test coating plate was subjected to a 600-hour weather resistance test using an accelerated weather resistance tester (trade name “Sunshine Wetherometer 1”, manufactured by Suga Test Instruments Co., Ltd.). . Thereafter, a contaminant consisting of a mixture of mud, carbon black, mineral oil and clay was deposited on the flanks and lightly rubbed against the coated surface of each test coating. This was left for 24 hours in a constant temperature and humidity chamber at 20 ° C. and 75% RH, and then the coated surface was washed with running water, and the stain resistance of the coating film was visually evaluated according to the following criteria.

[0148] A: No dirt remains and stain resistance is good. B: Some dirt remains and stain resistance is slightly inferior. C: Very little dirt remains and stain resistance is poor.

Table 14 shows the test results of the coating film performance of each coating composition obtained in Examples 14 to 28 and Comparative Examples 7 to 16.

[0150] [Table 7]

Table 3

[0151] [Table 8]

Table 3 (continued)

Example Comparison example

27 28 7 8 9 10 11 12 13 14 15 16 Scratch resistance 1 Recruitment 94 92 41 15 50 13 70 68 79 76 20 11 Acid resistance Visual A A B A B A C C C C B B

Etch 0.4 0.2 0.8 0.1 1.1 0.3 2.5 2.1 2.0 3.0 1.8 2.0 Pollution-resistant 'raw A A B A B B C C C C C C

Claims

The scope of the claims

[1] (a) an alicyclic hydrocarbon group-containing polymerizable unsaturated monomer having 3 to 20 carbon atoms, (b) styrene, (c) a hydroxyl group-containing polymerizable unsaturated monomer, (d) A hydrocarbon group-containing polymerizable unsaturated monomer having a branched structure having 8 to 22 carbon atoms, and (e) other polymerizable unsaturated monomer, based on the total weight of the mixture. The monomer (a) content is 3 to 40% by weight, the monomer (b) content is 3 to 40% by weight, and the monomer (c) content is 24 to 50% by weight. , The monomer (d) content is 3 to 40% by weight, the monomer (e) content is 0.:! To 41% by weight, the monomers ( _a ), (b) and (d) A resin obtained by copolymerizing a monomer mixture having a total content of 35 to 70% by weight,

[2] Bridged alicyclic hydrocarbon in which the alicyclic hydrocarbon group in the alicyclic hydrocarbon group-containing polymerizable unsaturated monomer (a) is a isobornyl group, a tricyclodecanyl group or an adamantyl group The resin according to claim 1, which is a group.

[3] The resin according to claim 1, wherein the hydroxyl group-containing polymerizable unsaturated monomer (c) is a polymerizable unsaturated monomer having a hydroxyl group-containing hydrocarbon group having 4 to 20 carbon atoms.

[4] A hydrocarbon group-containing polymerizable unsaturated monomer having 8 to 22 carbon atoms having a branched structure (d) Force General formula (1)

[Chemical 1]

2. The resin according to claim 1, which is a (meth) acrylic acid alkyl ester having two t-butyl groups in a molecule represented by (wherein X represents a hydrogen atom or a methyl group).

[5] The other polymerizable unsaturated monomer (e) is (meth) acrylic acid linear: From the group consisting of branched alkyl esters, (meth) acrylic acid linear alkyl esters having 8 to 22 carbon atoms, acidic functional group-containing polymerizable unsaturated monomers, and epoxy group-containing polymerizable unsaturated monomers. 2. The resin according to claim 1, which is at least one monomer selected.

[6] (A) the hydroxyl group-containing resin according to claim 1, and

(B) a reaction product of an aliphatic diisocyanate and a number average molecular weight of 400 to 1,500 polyforce prolataton polyol or polyether polyol, with an isocyanate content of 5 to 15% by weight, 3 to A coating composition characterized by containing a 9-functional aliphatic polyisocyanate baboon compound.

[7] The blend ratio of the aliphatic polyisocyanate compound (B) is 0.5 to 2.0 for the isocyanate group of the component (B) per equivalent of hydroxyl group of the hydroxyl group-containing resin (A). The coating composition according to claim 6, wherein the coating composition is an equivalent amount.

[8] The coating composition according to claim 6, further comprising (C) an acidic phosphate ester compound and / or an amine neutralized product thereof.

[9] The coating composition according to claim 6, wherein the coating composition is for an overcoat clearcoat paint.