JP3124360B2 - Curable composition for paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the curability of paints used for coating various applications such as building exteriors, automobiles, household appliances, plastics, etc., especially for applications requiring weather resistance, elasticity and flexibility. Composition.

[0002]

2. Description of the Related Art Various types of architectural finishes have been developed to date, for example, for the purpose of protecting the appearance of buildings and the protection of frames. But,
In the case of a non-flexible coating film, if the foundation cracks due to the deterioration of the building, the coating film also cracks, losing the functions of maintaining the appearance and protecting the frame. In order to solve this drawback, even if the building cracks, the coating film does not crack, and a flexible and stretchable waterproof elastic coating material that prevents the deterioration of the building as a continuous coating film has been developed. I have.

[0003] However, these elastic coating materials are not sufficient in terms of weather resistance. In the long term, they are cracked due to deterioration of the base such as cracks due to deterioration, thereby maintaining aesthetic appearance and protecting the frame. I can't do that.

[0004] Coating materials having high weather resistance, such as fluororesins, have also been developed. However, even with coating films made from these coating materials, the surface of the coating film is liable to be stained due to the unique properties of the fluororesins, resulting in poor appearance. There is a disadvantage that it is easy.

In order to remedy such drawbacks, the coating must have elasticity and flexibility, ie, elongation of more than 80%,
It is necessary that the weather resistance is good and the stain on the coating film surface is small (stain resistance is good).

[0006] However, since elongation and stain resistance are physical properties that are contradictory, it is very difficult to optimize the balance and to simultaneously impart weather resistance and workability.

On the other hand, a hydrolyzable silyl group-containing copolymer is crosslinked by moisture in the air in the presence of a curing agent to form a coating film having excellent weather resistance, chemical resistance, and adhesion to inorganic substrates. It is known to form. Taking advantage of this feature, a method of blending a soft component is also conceivable in order to make the coating film more stretchable.However, even if an attempt is made to blend the hydrolyzable silyl group-containing copolymer with the soft component, they do not become compatible and practical The fact is that no paint that can be converted has been obtained.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve these problems, and as a result, have found that a polyester macromonomer containing a hydrolyzable silyl group and an acrylic monomer have a co-polymerization property. The mixture of the coalesced and the polyester compound containing a hydrolyzable silyl group at both ends has very good compatibility, and by combining this with a curing catalyst, it has a good balance between elongation and stain resistance. The present inventors have found that it is possible to simultaneously satisfy the opposite properties, e.g., elongation and stain resistance, and to obtain a paint having good weather resistance and workability, and have completed the present invention.

That is, the present invention relates to (A) a polymer having a polymerizable carbon-carbon double bond and a hydrolyzable silyl group in one molecule and a main chain having a number average molecular weight of 500 to 5,000. A copolymer of a macromonomer consisting of polyester having a transition temperature of -10 ° C or less and an acrylic monomer (hereinafter also referred to as a hydrolyzable silyl group-containing vinyl polymer), (B) a hydrolyzable silyl group at both terminals (C) curing catalyst and (D) dehydrating agent and / or
(E) The present invention relates to a curable composition for coatings comprising a solvent and having a cured film elongation of 80% or more.

[0010]

EXAMPLES The vinyl polymer containing a hydrolyzable silyl group as the component (A) used in the present invention has a polymerizable carbon-
A macromonomer having a carbon double bond and a hydrolyzable silyl group and having a main chain substantially having a glass transition temperature of −10 ° C. or less, a number average molecular weight of 500 to 5,000, and an acrylic monomer; Is a copolymer of

The above-mentioned macromonomer imparts compatibility and flexibility to the component (B), facilitates control of the molecular weight and molecular weight distribution of the obtained copolymer, and has a low viscosity and a good storage stability. Wherein the acrylic monomer is (B)
It is a component for improving compatibility with components, flexibility, and weather resistance.

[0012] As described above, the macromonomer comprises 1
The polymer has a polymerizable carbon-carbon double bond and a hydrolyzable silyl group in the molecule, but the number of polymerizable carbon-carbon double bonds contained in one molecule is controlled by the molecular weight and molecular weight distribution of the copolymer. It is preferable that the number is one from the viewpoint of storage stability, and the molecular weight per polymerizable carbon-carbon double bond is 500.
It is preferably from 5,000 to 5,000, and it is preferably located at the terminal of the molecular chain from the viewpoint of polymerizability and compatibility with the component (B).

The hydrolyzable silyl group is, for example, a compound represented by the following general formula (I):

[0014]

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A group represented by the general formula
R ^{1 in} (I) is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, and X is a halogen atom, an alkoxy group, an acyloxy group, an aminoxy group, a phenoxy group, a thioalkoxy group, or an amino group. The selected hydrolyzable group, a is 0
整数 2. Among such hydrolyzable silyl groups, bifunctional ones (two Xs) are preferable in terms of a good balance between elongation of the coating film and stain resistance. It is preferable from the viewpoint of storage stability.

From the viewpoint of crosslinking reactivity (or curability), one or more, preferably two or less, hydrolyzable silyl groups are preferably contained in one macromonomer molecule. 400 as molecular weight per unit
It is preferably from 5,000 to 5,000, and it is preferably located at the terminal of the molecular chain in view of crosslinking reactivity and weather resistance.

The number average molecular weight of the macromonomer is from 500 to 5,000 as described above, preferably from 500 to 4,000. If the number average molecular weight is less than 500, the compatibility with the component (B) will be poor, and if it exceeds 5,000, the copolymer will have a high molecular weight, leading to a decrease in storage stability.

Further, the main chain of the macromonomer is substantially composed of a polyester having a glass transition temperature of -10 ° C. or less, that is, in order to increase the compatibility with the hydrolyzable silyl group-containing polyester compound of the component (B), (A) Ingredients and (B)
Further promotes the crosslinking reaction of the components and imparts elongation characteristics of the cured coating film.

Specific examples of the macromonomer include, for example, the following general formula (II):

[0020]

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A compound represented by the general formula (III):

[0022]

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A compound represented by the general formula (IV):

[0024]

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A compound represented by the general formula (V):

[0026]

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And the like.

In the above formula, R ¹ , X and a are the same as described above, and R ² and R ⁴ are a hydrogen atom or a methyl group, an ethyl group,
C1-C10 such as butyl, hexyl and octyl groups
A monovalent alkyl group, an aryl group such as a phenyl group, or an aralkyl group such as a benzyl group, and R ³ and R ⁵ are a divalent group having 1 to 10 carbon atoms such as a methylene group, an ethylene group, a propylene group, and a butylene group. A divalent aryl group such as an alkylene group and a phenylene group,

[0029]

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R ⁶ is an alkyl group having 1 to 30 carbon atoms such as a hexyl group, a cyclohexyl group, a lauryl group, a stearyl group, an aryl group such as a phenyl group, a benzyl group, an aralkyl group;

[0031]

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R ⁷ and R ⁸ are a hydrogen atom or a methyl group,
A monovalent alkyl group having 1 to 10 carbon atoms such as an ethyl group and a butyl group, an aryl group such as a phenyl group, and an aralkyl group such as a benzyl group. Y is -S- or

[0033]

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(Where R ⁹ is a hydrogen atom or a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group,
An alkyl group having 1 to 10 carbon atoms such as an octyl group),
Z includes a polyester chain, and further includes a group derived from a diisocyanate compound such as isophorone diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, and diphenylmethane diisocyanate, a polymethylene chain, a polyether chain,
It is a divalent organic group that can contain at least one organic group selected from an organopolysiloxane chain, a polyamide chain, a polyurethane chain, and a polycarbonate chain. Further, m is an integer of 1 to 10, and k is an integer of 1 to 10.

Among the macromonomers, the main chain substantially consisting of polyester is

[0036]

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Those containing the unit represented by the formula (B)
It is preferable in terms of compatibility with the components and imparting flexibility of the coating film, and the number of the units contained is preferably about 1 to 30. Also,

[0038]

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Those containing a unit having a group represented by the formula (1) are preferred from the viewpoint of imparting solvent resistance to the coating film, and the number of the units contained is preferably about 1 to 10.

The macromonomer may be used alone or in combination of two or more.

The method for producing the macromonomer is as follows:
For example, JP-A-63-112605 and JP-A-63-112610
And the methods described in Japanese Patent Application Publication No.

By copolymerization with the macromonomer, (A)
The acrylic monomer constituting the component is not particularly limited as long as it can be copolymerized with the macromonomer.

Specific examples of the acrylic monomer include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and stearyl (meth) acrylate. Acrylate,
Nitrile group-containing vinyl compounds such as benzyl (meth) acrylate, cyclohexyl (meth) acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) acrylate, perfluorocyclohexyl (meth) acrylate, and (meth) acrylonitrile; glycidyl ( Epoxy group-containing vinyl compounds such as meth) acrylate; basic nitrogen atom-containing vinyl compounds such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, vinylpyridine, and aminoethyl vinyl ether; (meth)
Acrylamide, itaconic diamide, α-ethyl (meth) acrylamide, crotonamide, maleic diamide, fumaric diamide, N-vinylpyrrolidone, N-
Amide group-containing vinyl compounds such as butoxymethyl (meth) acrylamide, N, N-dimethylacrylamide, N-methylacrylamide, and acryloylmorpholine;
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxyethyl vinyl ether, N-methylol (meth) acrylamide, Alonix 5700 (Toa Gosei Chemical Industry Co., Ltd.)
Placcel FA-1, Placcel FA-4, Placcel FM-1, Pl
hydroxyl-containing vinyl compounds such as accel FM-4 (all manufactured by Daicel Chemical Industries, Ltd.); hydroxyalkyl esters of α, β-ethylenically unsaturated carboxylic acids such as hydroxyalkyl esters of (meth) acrylic acid; Phosphoric ester group-containing vinyl compounds or vinyl compounds such as (meth) acrylates containing urethane bonds or siloxane bonds, AS-6, AN-6, AA-6, AK which are macromonomers manufactured by Toagosei Chemical Industry Co., Ltd. Compounds such as -5; and (meth) acrylic acid.

[0044] Of the acrylic monomers, butyl methacrylate is particularly preferred because the elongation of the coating film is improved and the compatibility with the component (B) is also improved.

The polymerization ratio of the macromonomer and the acrylic monomer is 1 to 50 parts, preferably 5 to 30 parts, so that the total amount is 100 parts (parts by weight, the same applies hereinafter).
It is preferred to use parts. If the amount is less than 1 part, the compatibility with the component (B) tends to be poor, and if it exceeds 50 parts, the composition tends to be too flexible, and the stain resistance and weather resistance tend to be poor. Therefore, the amount of the acrylic monomer used is 99
When the amount is less than 50 parts, the weather resistance and water resistance tend to deteriorate, and when the amount exceeds 99 parts, the compatibility with the component (B) tends to deteriorate. is there. Especially when butyl methacrylate is used,
It is preferably 60 parts, more preferably 10 to 40 parts.

The copolymer of the component (A) (copolymer (A)) used in the present invention is produced by copolymerizing the macromonomer with an acrylic monomer.

The method for producing the copolymer of the macromonomer and the acrylic monomer is described in, for example, JP-A-54-36395.
JP-A-57-36109, JP-A-58-157810, etc. are exemplified, but are produced by a solution polymerization method using an azo radical initiator such as azobisisobutyronitrile. Is preferred from the viewpoint of easiness of polymerization.

If necessary, n-dodecyl mercaptan, t-dodecyl mercaptan, n-butyl mercaptan, γ-mercaptopropyltrimethoxysilane, γ
-Mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane,

[0049]

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The molecular weight may be adjusted by using a chain transfer agent such as In particular, if a chain transfer agent having a hydrolyzable silyl group in the molecule, for example, γ-mercaptopropyltrimethoxysilane, is used, the desired vinyl copolymer can be obtained.

The polymerization solvent used for the solution polymerization is not particularly limited as long as it is a non-reactive solvent. Specific examples of such solvents include, for example, hydrocarbons such as toluene, xylene, n-hexane and cyclohexane, acetates such as ethyl acetate and butyl acetate, and alcohols such as methanol, ethanol, isopropanol and n-butanol. And ethers such as ethyl cellosolve, butyl cellosolve, and cellosolve acetate, and ketones such as methyl ethyl ketone, ethyl acetoacetate, acetylacetone, diacetone alcohol, methyl isobutyl ketone, and acetone.

The component (A) thus obtained contains at least one silicon atom (hydrolyzable silyl group) bonded to a terminal and / or side chain of the main chain with a hydrolyzable group in one molecule. It preferably has 2 to 10, and has a number average molecular weight of 2000
About 50,000, preferably about 5,000 to 40,000, and more preferably about 10,000 to 30,000.Since the main chain is substantially composed of an acrylic copolymer chain, the cured product has weather resistance, chemical resistance, water resistance, etc. And a copolymer having characteristics such as high surface hardness and excellent stain resistance. The phrase that the main chain substantially consists of an acrylic copolymer chain means that the carbon-carbon bond generated by polymerization of the acrylic monomer is 50% or more of the main chain.

Since the alkoxysilyl group is bonded to a carbon atom, the cured product has improved water resistance, alkali resistance and acid resistance. If the number of hydrolyzable silyl groups, for example, alkoxysilyl groups in one molecule is less than 1, the solvent resistance of the coating film obtained from the composition of the present invention tends to decrease.

On the other hand, if the number average molecular weight is too low, the amount of the non-crosslinking component increases, and if the number average molecular weight is too high, the storage stability tends to deteriorate.

The main chain or side chain of the component (A) may partially contain a urethane bond or a siloxane bond.

In producing the copolymer (A), the number of hydrolyzable silyl groups in the copolymer (A) is adjusted, the adhesion is improved, and the surface hardness is improved. A component copolymerizable with a macromonomer and an acrylic monomer may be copolymerized.

Specific examples of such a copolymer component include:
Unsaturated polycarboxylic acid esters such as diesters or half esters of unsaturated polycarboxylic acids (maleic acid, fumaric acid, itaconic acid, etc.) and C1-C20 linear or branched alcohols; styrene, α-methyl Styrene, chlorostyrene, styrenesulfonic acid, 4
-Aromatic hydrocarbon vinyl compounds such as hydroxystyrene and vinyltoluene; vinyl esters and allyl compounds such as vinyl acetate, vinyl propionate and diallyl phthalate; maleic acid, fumaric acid, itaconic acid, and salts thereof (alkali metal salts, Ammonium salts, amine salts, etc.), carboxylic acids, their salts, acid anhydrides; vinyl methyl ether, vinyl chloride, vinylidene chloride, chloroprene, propylene, butadiene, isoprene, maleimide, N-vinyl imidazole, vinyl sulfonic acid, etc. And a hydrolyzable silyl group-containing vinyl monomer having a molecular weight of less than 500.

The use of the hydrolyzable silyl group-containing vinyl monomer significantly improves the weather resistance, water resistance, alkali resistance, acid resistance and solvent resistance of the coating film. Such a hydrolyzable silyl group-containing vinyl monomer includes, for example, a compound represented by the general formula (VI):

[0059]

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And a monomer having a polymerizable carbon-carbon double bond at the same time.
R ^{10 in} I) is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group; an aryl group such as a phenyl group;
The monovalent hydrocarbon group selected from aralkyl groups such as benzyl group, X and a are the same as described above, but a = 1, that is, a bifunctional silyl group-containing monomer is used for elongation and curability of a coating film. It is preferable from the viewpoint of balance. X bonded to Si
And when R ¹⁰ is two or more, they may be the same group or different groups.

Examples of the hydrolyzable silyl group-containing vinyl monomer include, for example, an alkoxysilyl group-containing vinyl monomer.

[0062]

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And the like.

The hydrolyzable silyl group-containing monomer is 1
Species or two or more species may be used in combination.

The amount of the component copolymerizable with the macromonomer and the acrylic monomer is preferably 50 parts or less, more preferably 1 to 30 parts, based on 100 parts of the total amount of the macromonomer and the acrylic monomer. preferable. When the copolymerizable component is a hydrolyzable silyl group-containing monomer, the amount used is 1 to 50 with respect to 100 parts of the total monomer.
Parts, more preferably 2 to 20 parts, in terms of curability, weather resistance, water resistance and stain resistance.

The component (B) used in the present invention, which is composed of a polyester having a hydrolyzable silyl group at each end and having a main chain substantially having a glass transition temperature of -10 ° C. or less, can impart elasticity and flexibility. That is, it is a component for imparting elongation.

The hydrolyzable silyl group is the same as that contained in the component (A). In order to improve the balance between the elongation of the coating film and the stain resistance, and to improve the balance between the curability and the curability, it is preferable to use a bifunctional silyl group as a hydrolyzable silyl group at both ends.

The fact that the main chain substantially consists of polyester means that the polyester chain is contained by 50% or more.
In addition to the polyester chain, one or more of a polymethylene chain, a polyether chain, an organopolysiloxane chain, a polyamide chain, and a polyurethane chain may be contained in an amount not exceeding 50%.

The main chain may have a branch or two or more hydrolyzable silyl groups may be contained in one molecule, and the molecular weight per hydrolyzable silyl group is 500.
Preferably it is ~ 10000.

The number average molecular weight of the component (B) is preferably from 1,000 to 20,000, more preferably from 2,000 to 15,000, particularly preferably from 4000 to 10,000. If the number average molecular weight is less than 1,000, sufficient elongation cannot be obtained, and if it exceeds 20,000, compatibility becomes poor, and stain resistance and weather resistance tend to decrease.

Examples of such a component (B) include, for example, those represented by the general formula (VII):

[0072]

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A compound represented by the general formula (VIII):

[0074]

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A compound represented by the general formula (IX):

[0076]

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A compound represented by the general formula (X):

[0078]

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A compound represented by the general formula (XI):

[0080]

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A compound represented by the general formula (XII):

[0082]

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A compound represented by the general formula (XIII):

[0084]

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A compound represented by the general formula (XIV):

[0086]

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And the like.

In the above formula, R ¹¹ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a butyl group, a hexyl group or an octyl group; an aryl group such as a phenyl group; A monovalent hydrocarbon group selected from aralkyl groups, R ¹² and R ¹⁴ include a polyester chain,
And includes segments derived from diisocyanate compounds such as isophorone diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and further selected from polymethylene chains, polyether chains, organopolysiloxane chains, polyamide chains, and polyurethane chains. A divalent organic group that can include one or more organic groups;
R ¹³ and R ¹⁵ are selected from a hydrogen atom or an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a butyl group, a hexyl group, an octyl group, an aryl group such as a phenyl group, and an aralkyl group such as a benzyl group. Or a group derived from a monoisocyanate compound such as cyclohexyl isocyanate. R ¹⁰ , X and a are the same as above, and n is an integer of 1 or more. When each of X, R ¹⁰ , and R ¹¹ bonded to Si is two or more, they may be the same group or different groups.

Among these compounds, a caprolactone unit is used as a polyester chain.

[0090]

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Or valerolactone units, for example

[0092]

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(Where R ¹⁶ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a butyl group, a hexyl group, an octyl group,

[0094]

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A unit represented by the formula:

[0096]

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Those containing the unit represented by the formula or other polyester chains are preferable because of their excellent weather resistance, acid resistance and water resistance.

These compounds may be used alone,
Two or more kinds may be used in combination.

The following are typical production methods among the methods for synthesizing the compound (B).

[0100]

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[0101]

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[0102]

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In the above formula, R ¹⁷ and R ²⁰ are a hydrogen atom or a monovalent hydrocarbon group selected from alkyl groups, aryl groups and aralkyl groups having 1 to 10 carbon atoms, and R ¹⁸ is

[0104]

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A divalent aliphatic hydrocarbon group such as an isophoronyl group, a divalent aromatic hydrocarbon group such as a tolylene group or a xylylene group, R ¹⁹ is an alkyl group, an aryl group, an aralkyl group, a polyester group, or a polyether group , A polymethylene group, an organopolysiloxane group, a polyamide group, and a divalent organic group containing one or more organic groups selected from polyurethane groups, X, a, and n are the same as those described above for X and R bonded to Si. ^When each of ¹⁷ is two or more, they may be the same group or different groups.

The use ratio of the component (A) to the component (B) is such that the weight ratio of the component (A) / the component (B) is 20/80 to 99/1,
Further, the ratio is preferably 60/40 to 90/10 from the viewpoint of the balance between stain resistance and elongation and weather resistance.

Specific examples of the curing catalyst used as the component (C) in the present invention (hereinafter also referred to as curing catalyst (C)) include, for example, dibutyltin laurate, dibutyltin dimaleate, dioctyltin laurate, dioctyltin laurate, and the like. Organic tin compounds such as maleate and tin octylate; phosphoric acid, monomethyl phosphate, monoethyl phosphate, monobutyl phosphate, monooctyl phosphate, monodecyl phosphate, dimethyl phosphate,
Phosphoric acid or phosphoric acid ester such as diethyl phosphate, dibutyl phosphate, dioctyl phosphate, didecyl phosphate; propylene oxide, butylene oxide, cyclohexene oxide, glycidyl methacrylate, glycidol, acrylic glycidyl ether, γ-glycidoxypropyltrimethoxysilane, γ Glycidoxypropyltriethoxysilane, γ
-Glycidoxypropylmethyldimethoxysilane,

[0108]

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Addition products of epoxy compounds such as Cardura E manufactured by Yuka Shell Epoxy Co., Ltd., Epikote 828 and Epikote 1001 manufactured by Yuka Shell Epoxy Co., and phosphoric acid and / or monoacid phosphate. Organic titanate compounds; organic aluminum compounds; organic zirconium compounds; maleic acid, adipic acid, azelaic acid, sebacic acid, itaconic acid, citric acid, succinic acid, phthalic acid, trimellitic acid, pyromellitic acid, and their acid anhydrides And acidic compounds such as paratoluenesulfonic acid; hexylamine, di-2-ethylhexylamine, N, N
Amines such as dimethyldodecylamine and dodecylamine; mixtures or reactants of these amines with acidic phosphate esters; and alkaline compounds such as sodium hydroxide and potassium hydroxide.

Among these curing catalysts (C), organotin compounds, acidic phosphates, mixtures or reactants of acidic phosphates and amines, saturated or unsaturated polycarboxylic acids or their anhydrides, Silicon compound,
An organic titanate compound, an organic aluminum compound, an organic zirconium compound or a mixture thereof is preferred because of its high activity. Further, an organotin compound, an acid phosphate, a mixture of an acid phosphate and an amine or a reaction product is preferable.

These curing catalysts (C) may be used alone or in combination of two or more.

The amount of the component (C) used is usually 0.1 to 20 parts with respect to 100 parts of the solid content of the components (A) and (B).
Preferably it is 0.1 to 10 parts. (C) Component usage is 0.1
If the amount is less than 20 parts, the curability tends to decrease. If the amount exceeds 20 parts, the appearance of the coating film tends to decrease.

The composition of the present invention contains a dehydrating agent (component (D)) and / or a solvent (component (E)).

Specific examples of the dehydrating agent as the component (D) include, for example, methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, methyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyl Trimethoxysilane, methyl silicate,
Examples include hydrolyzable ester compounds such as ethyl silicate. These hydrolyzable ester compounds are
It may be added before the polymerization of the hydrolyzable silyl group-containing acrylic copolymer (A), after the polymerization, or during the polymerization. The compound (B) is preferably added after the synthesis from the viewpoint of preventing side reactions.

There is no particular limitation on the amount of the dehydrating agent used.
For 100 parts of solid content of component (A) and component (B),
The amount is 100 parts or less, preferably 50 parts or less. When the dehydrating agent is used alone without using a solvent, the amount is usually 0.5 to 100 parts, preferably 1 to 50 parts.

When a dehydrating agent is used together with a dehydration accelerator, the effect can be further enhanced.

Preferred examples of the dehydration accelerator include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid;
Organic acids such as formic acid, acetic acid, oxalic acid, benzoic acid, phthalic acid, p-toluenesulfonic acid, acrylic acid and methacrylic acid; metal salts of carboxylic acids such as alkyl titanates and lead octylate; tin octylate and dibutyl Tin dilaurate,
Carboxylic acid-type organotin compounds such as dioctyltin maleate; sulfide-type and mercaptide-type organotin compounds such as monobutyltin sulfide and dioctyltin mercaptide; organic tin oxides such as dioctyltin oxide;
Organotin compounds by reaction of organotin oxide with ester compounds such as ethyl silicate, ethyl silicate 40, dimethyl maleate and dioctyl phthalate; tetraethylene pentamine, triethylene diamine, N-β-aminoethyl-γ-aminopropyl tri Amines such as methoxysilane; alkaline catalysts such as potassium hydroxide and sodium hydroxide; and the like, but are not limited thereto. Of these, organic acids, inorganic acids and organic tin compounds are particularly effective.

These dehydration accelerators are based on 100 parts of the dehydration agent.
Usually, 0.0001 to 20 parts, preferably 0.001 to 10 parts are used. When a compound that is also the component (C) is used as a dehydration accelerator, the amount of the component (C) used is further increased by 0.1%.
To 20 parts, preferably 0.1 to 10 parts.

As the solvent (E) used in the composition of the present invention, any non-reactive solvent can be used.

Specific examples of such a solvent (E) include, for example, aliphatic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, alcohols, and the like used in general paints and coating agents. Ketones, esters, ethers, alcohol esters, ketone alcohols,
Examples include ether alcohols, ketone ethers, ketone esters, ester ethers and the like.

Preferred specific examples of the solvent as the component (E) include alcohols having 1 to 10 carbon atoms in the alkyl group. Examples of such alcohols include methyl alcohol, ethyl alcohol and n-propyl. Alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, n-amyl alcohol, isoamyl alcohol, hexyl alcohol, octyl alcohol, cellosolve and the like are used.

The amount of the solvent such as the alcohol is not particularly limited, but the solid content of the component (A) and the component (B) is not limited.
The amount is usually 100 parts or less, preferably 50 parts or less based on 100 parts, and when the solvent is used alone without using a dehydrating agent, the amount is usually 0.5 to 100 parts, preferably 2 to 50 parts.

(E) Alcohol as described above as a component,
In particular, when an alkyl alcohol is used, and when a hydrolyzable ester compound is used as the dehydrating agent, the storage stability is remarkably higher as compared with the case where the composition comprising the components (A) and (B) is stored. Be improved. The amount of the solvent exhibiting such an effect is, in the composition of the present invention.
It differs depending on the molecular weight and composition of the component (A) and the component (B), and cannot be specified unconditionally, but may be adjusted so that the composition has a solid concentration, viscosity, and the like that are practically necessary.

In the composition of the present invention, conventionally known ultraviolet absorbers, light stabilizers, antioxidants and the like can be used as additives.

As specific examples of the above-mentioned ultraviolet absorbent, for example, benzophenone-based, triazole-based, phenyl salicylate-based, diphenylacrylate-based, acetophenone-based and hindered amine-based ultraviolet absorbers are preferable.

As the light stabilizer, for example, bis (2,
2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 2- (3,5-di-tert-butyl-4-) Hydroxybenzyl)
Bis (1,2,2,6,6-pentamethyl-4-2-n-butylmalonate
-Piperidyl), tetrakis (2,2,6,6-tetramethyl-4)
-Piperidyl) -1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate can give.

These may be used alone or in combination of two or more.

When the above-mentioned ultraviolet absorber and light stabilizer are blended, the weather resistance is remarkably improved. In addition, weather resistance can be further improved by using an ultraviolet absorber and a light stabilizer in combination.

The compounding amount of the ultraviolet absorber, the light stabilizer and the antioxidant is usually 0.1 to 10 parts, preferably 1 to 5 parts, per 100 parts of the solid content of the clear paint. When a light stabilizer is used, the amount of the light stabilizer is usually 0.1 to 10 parts, preferably 1 to 5 parts, per 100 parts of the solid content of the clear paint.
Department. When using an antioxidant, its compounding amount is
Normally 0.1 to 10 per 100 parts of solid content of clear paint
Parts, preferably 1 to 5 parts.

Next, a method for preparing the composition of the present invention will be described.

The preparation method is not particularly limited.
Components (A) and (B) are cold-blended or mixed and then partially reacted by heating (hot blending) and mixed with component (D) and / or (E). Then, the composition of the present invention is prepared by mixing and reacting these mixtures with the component (C).

The composition of the present invention thus prepared gives a coating film having a good balance between stain resistance and elongation, having hardness, and excellent in curability and weather resistance.

Next, the composition of the present invention will be described based on examples.

Production Example 1 [Synthesis of Hydrolyzable Silyl Group-Containing Vinyl Polymer without Copolymerization of Macromonomer] Xylene was placed in a reaction vessel equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel. Charge 45.9 parts while introducing nitrogen gas
After the temperature was raised to 110 ° C., a mixture (a) having the following composition was dropped at a constant speed over 5 hours using a dropping funnel.

(Mixture (a)) 41.7 parts of butyl acrylate 51.2 parts of methyl methacrylate 9.5 parts of γ-methacryloxypropyl-trimethoxysilane 13.5 parts of xylene 1.8 parts of 2,2'-azobisisobutyronitrile 1.8 parts of mixture (a) After the completion of the dropwise addition, 0.2 parts of 2,2'-azobisisobutyronitrile and 5 parts of toluene were dropped at a constant speed over 1 hour. After completion of the dropwise addition, the mixture was aged at 110 ° C. for 2 hours, cooled, and xylene was added to the resin solution to adjust the solid content to 60%, thereby obtaining a resin solution (1). Table 1 shows the properties of the obtained resin solution (1).

Production Example 2 [Synthesis of Macromonomer Copolymerized Hydrolyzable Silyl Group-Containing Vinyl Polymer (A)] (i) Synthesis of Macromonomer Stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping To a reaction vessel equipped with a funnel were charged 8.9 parts of toluene and 13.7 parts of isophorone diisocyanate, and 8.0 parts of 2-hydroxyethyl methacrylate was added dropwise over 1 hour while stirring at room temperature while introducing nitrogen gas. At this time, sufficient care was taken because heat was generated by the reaction. After completion of the dropwise addition, stirring was continued for 1 hour at room temperature, then the temperature was raised to 100 ° C., and 51.4 parts of Placcel FA-4 (manufactured by Daicel Chemical Industries, Ltd.) and 8.9 parts of toluene were dropped at a constant rate over 2 hours. After completion of dropping, the mixture was aged for 1 hour, cooled to room temperature, added with 16.2 parts of γ-aminopropyltrimethoxysilane and 2.7 parts of toluene, allowed to react at room temperature for 1 hour, and then heated to 60 ° C.
The reaction was continued for 30 minutes. Cool to room temperature again, add 10.7 parts of cyclohexyl isocyanate and 2.7 parts of toluene, and add 30 parts.
After reacting for 60 minutes, the temperature was raised to 60 ° C. to terminate the reaction. After cooling, 5 parts of methanol, 2 parts of methyl orthoacetate and toluene were added so that the resulting macromonomer-containing liquid was adjusted to have a resin solids concentration of 75%. The macromonomer obtained has the formula:

[0137]

Embedded image

Is represented by

(Ii) Synthesis of vinyl copolymer In the same manner as in Production Example 1, a mixture (b) having the following composition was added.

(Mixture (b)) 13.6 parts of the macromonomer solution obtained in (i) 32.2 parts of butyl acrylate 49.8 parts of methyl methacrylate 4.4 parts of γ-methacryloxypropyl trimethoxysilane 4.4 parts of xylene 13.5 parts of 2,2′-azo 1.8 parts of bisisobutyronitrile After completion of the dropwise addition of the mixture (b), 0.2 parts of 2,2'-azobisisobutyronitrile and 3.8 parts of toluene were added dropwise at a constant rate over 1 hour. After completion of the dropwise addition, the mixture was aged at 110 ° C. for 2 hours and then cooled.
To obtain a resin solution (2). Table 1 shows the properties of the obtained resin solution (2).

Preparation Example 3 [Synthesis of Macromonomer Copolymerized Hydrolyzable Silyl Group-Containing Vinyl Polymer (A)] In the same manner as in Preparation Example 1, a mixture (c) having the following composition was added.

(Mixture (c)) The macromonomer solution obtained in Production Example 2 (i) 16.2 parts Butyl acrylate 34.3 parts Methyl methacrylate 21.5 parts Butyl methacrylate 23.9 parts γ-methacryloxypropyl trimethoxysilane 4.1 parts xylene 13.5 parts 2,2'-azobisisobutyronitrile 1.8 parts After the completion of dropping of the mixture (c), 0.2 parts of 2,2'-azobisisobutyronitrile and 3.8 parts of toluene were dropped at a constant rate over 1 hour. . After completion of the dropping, the mixture was aged at 110 ° C. for 2 hours, cooled, and xylene was added to the resin solution to obtain a solid content of 60%.
And a resin solution (3) was obtained. Table 1 shows the properties of the obtained resin solution (3).

Production Example 4 [Synthesis of Polyester Compound (B) Having Hydrolyzable Silyl Group at Both Terminals] Toluene 9.2 was placed in a reaction vessel equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel. And 13.5 parts of isophorone diisocyanate, and heated to 100 ° C. while stirring while introducing nitrogen gas. To this mixture, 56.4 parts of Placcel L212AL (manufactured by Daicel Chemical Industries, Ltd.) was dropped at a constant speed over 1 hour, and after completion of the dropwise addition, the mixture was stirred for 2 hours. And 4.6 parts of toluene were added dropwise over 1 hour.
After completion of the dropwise addition, stirring was continued for 2 hours. Cool to room temperature, γ-
6.4 parts of aminopropyltrimethoxysilane and toluene 4.
6 parts were added dropwise, and after 1 hour, the temperature was raised to 60 ° C., and the reaction was continued for 30 minutes. After cooling to room temperature again, 4.2 parts of cyclohexyl isocyanate and 4.6 parts of toluene were added dropwise, and after 30 minutes, the temperature was raised to 60 ° C.
As (D), 3 parts of methyl orthoacetate and toluene were added to adjust the solid content to 75%, and a resin solution (4) was obtained. Table 1 shows the properties of the obtained resin solution (4).

Production Example 5 [Macromonomer Copolymer Synthesis of Hydrolyzable Silyl Group-Containing Vinyl Copolymer (A)] (i) Synthesis of Macromonomer In the same reaction vessel as in Production Example 2, toluene 8 was added. .
9 parts and 13.7 parts of isophorone diisocyanate were charged, and 8.0 parts of 2-hydroxyethyl methacrylate was added dropwise over 1 hour while stirring at room temperature while introducing nitrogen gas.
After dropping, continue stirring for 1 hour at room temperature, then 100 ℃
The temperature was raised to Placcel FA-4 (Daicel Chemical Co., Ltd.) 51.4
And 8.9 parts of toluene were dropped at a constant speed over 2 hours. After completion of the dropwise addition, stirring was continued for 1 hour, and then cooled to room temperature.
After adding 16.2 parts of aminopropylmethyldimethoxysilane and 2.7 parts of toluene, the mixture was reacted at room temperature for 1 hour, and then reacted at 60 ° C.
The reaction was continued for 30 minutes. Cool to room temperature again, cyclohexyl isocyanate 10.7 parts and toluene 2.
After adding 7 parts and reacting for 30 minutes, the temperature was raised to 60 ° C. to complete the reaction. After cooling, 5 parts of methanol, 2 parts of methyl orthoacetate and toluene were added so that the resulting macromonomer-containing liquid was adjusted to have a resin solids concentration of 75%. This macromonomer has the formula:

[0145]

Embedded image

Is represented by

(Ii) Synthesis of vinyl copolymer In the same manner as in Production Example 1, a mixture (d) having the following composition was added.

(Mixture (d)) 16.2 parts of the macromer solution obtained in (i) 34.3 parts of butyl acrylate 21.5 parts of methyl methacrylate 23.9 parts of butyl methacrylate 24.1 parts of γ-methacryloxypropylmethyl dimethoxysilane 4.1 parts of xylene 13.5 parts of 2, 1.8 parts of 2'-azobisisobutyronitrile After completion of the dropwise addition of the mixture (d), 0.2 parts of 2,2'-azobisisobutyronitrile and 3.8 parts of toluene were dropped at a constant rate over 1 hour. After completion of the dropwise addition, the mixture was aged at 110 ° C. for 2 hours and then cooled.
And a resin solution (5) was obtained. Table 1 shows the properties of the obtained resin solution (5).

Production Example 6 [Synthesis of Polyester Compound (B) Having Hydrolyzable Silyl Group at Both Terminals] Using the same reaction vessel as in Production Example 4, 9.2 parts of toluene and 13.5 parts of isophorone diisocyanate were used.
The temperature was raised to 100 ° C. while introducing nitrogen gas. To this mixture, 56.4 parts of Placcel L212AL (manufactured by Daicel Chemical Industries, Ltd.) was dropped at a constant speed over 1 hour, and after completion of the dropping, the mixture was stirred for 2 hours, and then, Placcel FA-4 (manufactured by Daicel Chemical Industries, Ltd.) 19.5 And 4.6 parts of toluene were added dropwise over 1 hour, and stirring was continued for 2 hours after completion of the addition. Cool to room temperature,
6.4 parts of γ-aminopropylmethyldimethoxysilane and 4.6 parts of toluene were added dropwise, and after 1 hour, the temperature was raised to 60 ° C., and the reaction was continued for 30 minutes. After cooling to room temperature again, 4.2 parts of cyclohexyl isocyanate and 4.6 parts of toluene were added dropwise. After 30 minutes, the temperature was raised to 60 ° C. After cooling, 3 parts of methyl orthoacetate and toluene were added to adjust the solid concentration to 75%. Then, a resin solution (6) was obtained. Table 1 shows the properties of the obtained resin solution (6).

[0150]

[Table 1]

Example 1 To 49.0 parts of the hydrolyzable silyl group-containing vinyl polymer (A) obtained in Production Example 2, 18.0 parts of titanium oxide (CR-90, manufactured by Ishihara Sangyo KK) and 18.0 parts of a dehydrating agent ( As D), 2.1 parts of orthoacetic acid methyl ester and 3.6 parts of xylene were added, and the mixture was shaken for 2 hours. Further, 21.0 parts of the polyester compound (B) containing a hydrolyzable silyl group obtained in Production Example 4 and 6.3 parts of xylene were added.
The mixture was shaken for 30 minutes to prepare a white enamel. With 100 parts of this white enamel, No. 9 was used as a curing catalyst (C).
Add 0.84 parts of 18 (reacted product of dibutyltin oxide and di (DOP), manufactured by Sankyokisei Co., Ltd.) and 38.3 parts of xylene, mix well, obtain the composition, paint, and prepare a film and test plate The stain resistance, elongation, and perozos hardness were evaluated. The results are shown in Table 2 together with the compatibility and the gel fraction.

(Compatibility) The resin solution was spotted on a glass plate, dried, and the transparency was visually evaluated on a 10-point scale.

10 points: completely transparent 9-7 points: slightly cloudy (points depending on the degree) 6-4 points: cloudy (points depending on the degree) 3-1 points: almost white 0 points: The evaluation by the pure white (stain resistance) accelerating method is as follows. One day after coating, one test plate is divided into two parts, one side is coated with powdered carbon black, the other side is coated with a 2% concentration carbon water slurry, and after standing for one day, a gum tape is applied. The free carbon is removed by adhesion by pressing, and the degree of the stain due to the carbon is evaluated by ΔE before the test.

In the evaluation by the actual exposure method, the test plate was exposed in Kagoshima city for one year, and the degree of contamination before and after cleaning was evaluated by ΔE from before the test.

(Elongation) Using an autograph, the stretching is performed at 23 ° C., a load of 5 kg, and a pulling speed of 200 mm / min.

(Perozos hardness) At 23 ° C., it is measured with a Perozos hardness meter.

Example 2 Titanium oxide (CR-90, Ishihara Sangyo Co., Ltd.) was added to 49.0 parts of the hydrolyzable silyl group-containing vinyl polymer (A) obtained in Production Example 3.
18.0 parts, 2.1 parts of methyl orthoacetate and 3.6 parts of xylene as a dehydrating agent (D) were added and shaken for 2 hours. Further, the polyester compound (B) containing a hydrolyzable silyl group obtained in Production Example 4 was added. 21.0 parts and xylene 6.3 parts were added and shaken for 30 minutes to prepare a white enamel. This white enamel 100
No. 918 (reacted product of dibutyltin oxide and DOP, manufactured by Sankyoki Gosei Co., Ltd.)
Add 84 parts and 38.3 parts of xylene, mix well, paint, produce film and test plate, stain resistance, elongation,
Perozos hardness was evaluated. The results are shown in Table 2 together with the compatibility and the gel fraction.

Example 3 Titanium oxide (CR-90, Ishihara Sangyo Co., Ltd.) was added to 49.0 parts of the hydrolyzable silyl group-containing vinyl polymer (A) obtained in Production Example 5.
18.0 parts, 2.1 parts of methyl orthoacetate and 3.6 parts of xylene as dehydrating agents were added and shaken for 2 hours.
21.0 parts of the hydrolyzable silyl group-containing polyester compound (B) obtained above and 6.3 parts of xylene were added and shaken for 30 minutes to prepare a white enamel. To 100 parts of this white enamel, 0.84 parts of No. 918 (reacted product of dibutyltin oxide and DOP, manufactured by Sankyokisei Co., Ltd.) as a curing catalyst (C) and 38.3 parts of xylene were added, and the mixture was thoroughly mixed and painted. , A film and a test plate were prepared, and stain resistance, elongation, and perozos hardness were evaluated. The results are shown in Table 2 together with the compatibility and the gel fraction.

Comparative Example 1 Titanium oxide (CR-90, manufactured by Ishihara Sangyo Co., Ltd.) was added to 49.0 parts of the hydrolyzable silyl group-containing vinyl polymer obtained in Production Example 1.
18.0 parts, 2.1 parts of methyl orthoacetate and 3.6 parts of xylene as a dehydrating agent (D) were added, and the mixture was shaken for 2 hours. Further, the polyester compound having a hydrolyzable silyl group (B) 21.0 obtained in Production Example 4 was added. And 6.3 parts of xylene were added and shaken for 30 minutes to prepare a white enamel. To 100 parts of this white enamel, 0.84 part of No. 918 (reacted product of dibutyltin oxide and DOP, manufactured by Sankyokisei Co., Ltd.) and 38.3 parts of xylene were added as curing catalysts, mixed well, and then coated. Further, a test plate was prepared, and stain resistance, elongation, and perozos hardness were evaluated. The results are shown in Table 2 together with the compatibility and the gel fraction.

Comparative Example 2 70.0 parts of the hydrolyzable silyl group-containing vinyl polymer obtained in Production Example 1, titanium oxide (CR-90, manufactured by Ishihara Sangyo Co., Ltd.)
18.0 parts, as dehydrating agent (D), methyl orthoacetate
2.1 parts and 9.9 parts of xylene were added and shaken to prepare a white enamel. To 100 parts of this white enamel, 0.84 parts of No. 918 (reacted product of dibutyltin oxide and DOP, manufactured by Sankyokisei Co., Ltd.) and 38.3 parts of xylene were added as curing catalysts, mixed thoroughly, and coated. Further, a test plate was prepared, and stain resistance, elongation, and perozos hardness were evaluated.
The results are shown in Table 2 together with the compatibility and the gel fraction.

[0161]

[Table 2]

From the evaluation results in Table 2, the composition of the present invention was
It can be seen that the composition has an improved balance between stain resistance and elongation.

[0163]

The balance between stain resistance and elongation is not always good in ordinary elastic paints, which often causes drawbacks. However, the composition of the present invention has a sufficient balance between stain resistance and elongation. It has good hardness, good hardness, good curability, and excellent weather resistance.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C09D 1/00-201/10

Claims (12)

(57) [Claims] (A) a molecule having both a polymerizable carbon-carbon double bond and a hydrolyzable silyl group in one molecule and having a number average molecular weight of 500
(B) a main chain containing a hydrolyzable silyl group at both ends, wherein the main chain having a molecular weight of 50005000 is substantially a glass transition temperature of -10 ° C. or lower and a copolymer of an acrylic monomer and a macromonomer. Consisting essentially of a polyester having a glass transition temperature of -10 ° C or lower, (C) a curing catalyst, and (D) a dehydrating agent and / or a (E) solvent, and the cured film has an elongation of 80% or more. A curable composition for a paint. 2. The composition according to claim 1, wherein the component (A) is a copolymer of the macromonomer and an acrylic monomer containing butyl methacrylate. 3. The hydrolyzable silyl group in the macromonomer is an alkoxysilyl group, and has a main chain substantially composed of polyester. The curable composition for a paint according to claim 1, which comprises: 4. The curable composition for paint according to claim 1, wherein the macromonomer contains a urethane bond in a molecule. 5. The curable composition for a paint according to claim 1, wherein the main chain of the component (B) consisting essentially of polyester comprises a polycaprolactone chain or a polyvalerolactone chain. 6. The method according to claim 1, wherein the component (B) has a main chain consisting essentially of polyester. The curable composition for a paint according to claim 1, which comprises: 7. The curing catalyst as the component (C) may be an organotin compound, an acid phosphate, a mixture or a reaction product of an acid phosphate and an amine, a saturated or unsaturated polycarboxylic acid, a saturated or unsaturated Acid anhydrides of polycarboxylic acids, reactive silicon compounds, organic titanate compounds,
The curable composition for a paint according to claim 1, which is an organic aluminum compound, an organic zirconium compound, or a mixture thereof. 8. The curable composition for a paint according to claim 1, wherein the dehydrating agent as the component (D) is a hydrolyzable ester compound. 9. The curable composition for a paint according to claim 1, wherein the solvent as the component (E) contains an alkyl alcohol. 10. The curable composition for a paint according to claim 1, which comprises a hydrolyzable ester compound as a dehydrating agent as the component (D) and an alkyl alcohol as a solvent as the component (E). 11. The curable composition according to claim 1, further comprising a hydrolyzable ester compound as a dehydrating agent (D), an alkyl alcohol as a solvent (E), and a dehydration accelerator. Composition. 12. The curable composition for a paint according to claim 1, further comprising an ultraviolet absorber, a light stabilizer and / or an antioxidant as an additive.