JPH11228903A - Curable composition for paint and painted material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition having excellent self-recoatability, good appearance and adhesiveness and an excellent balance of paint film characteristics such as weather resistance, contamination resistance or the like by blending a curing catalyst (B) and a mixed organic solvent (C) containing a hydrocarbon solvent with a vinyl copolymer (A) containing hydrolyzable silyl groups. SOLUTION: (A) Monomers having at least one hydrolyzable silyl group of the formula (wherein R<1> is H or 1-10C alkyl; R<2> is H, 1-10C alkyl, 6-10C aryl or 7-10 aralykl; and a is 0-2) which monomers contain 2-50 wt.% of alkyl (meth)acrylate whose alkyl group has not less than 8 carbon atoms is copolymerized to the principal chain of a vinyl polymer chain. (B) The component B is, for example, dibutyl tin laurate. (C) This composition contains not less than 50 wt.% of a hydrocarbon organic solvent. The formulation ratio is 0.001-10 pts.wt. of the component B and 10-500 pts.wt. of the component C based on 100 parts by weight of the component A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to metal, ceramic, glass, cement, ceramic moldings, plastics,
Buildings, bridges, household appliances, wood, paper, textiles, etc.
The present invention relates to a curable coating composition which can be suitably used for undercoating, intermediate coating, or topcoating of industrial equipment and the like, and an object to be coated using the same.

[0002] More specifically, it has a small influence on the environment at the time of coating and has excellent weather resistance, self-recoating property and stain resistance, and is particularly suitable for a coating material which can be suitably used as a top coating for exterior use. The present invention relates to a hydrophilic composition and a substrate.

[0003]

2. Description of the Related Art Conventionally, the surface of an industrial product such as a building made of ceramic materials, steel or the like, or a building material is coated with, for example, a fluororesin paint or an acrylic urethane paint.
Protecting the surface of buildings, etc. and at the same time imparting aesthetic effects.

[0004] However, in recent years, with the deterioration of the environment mainly in urban areas, higher stain resistance has been required for coating films using paints. To address this request,
As a base resin, a curable composition for coatings has been already developed in which a reactive silyl group-containing acrylic copolymer is used and further a silicon compound and / or a hydrolyzed condensate thereof is blended (for example, JP No. 54-91546, etc.).

However, conventional solvent-based paints include aromatic solvents having 8 or less carbon atoms such as toluene and xylene, ester solvents such as acetate, and ketone solvents such as methyl ethyl ketone (MEK). Since it contains a large amount, it is difficult to prevent the generation of odor during coating, and there is also a problem in self-recoating.

Further, if the amount of these solvents is reduced in order to suppress the odor during the coating, there arises a problem that the solubility of the resin becomes insufficient. Therefore, recently, water-based paints that do not use these solvents have been often used, but there is a demand for paintability in cold regions.

[0007]

SUMMARY OF THE INVENTION In view of the above, the present invention has little effect on the environment at the time of painting, and has excellent weather resistance, self-recoating property and stain resistance. In addition, an object of the present invention is to provide a curable composition for paint and an object to be coated, which can be used as a paint for undercoating or intermediate coating, and particularly can be suitably used for a topcoat for exterior use.

[0008]

According to the present invention, the main chain comprises a vinyl copolymer chain, and the terminal and / or the side chain carbon atom of the main chain has the following general formula (1):

[0009]

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(Wherein R ¹ is a hydrogen atom or a group having 1 to 1 carbon atoms)
Represents 10 alkyl groups, and when there are plural alkyl groups, they may be the same or different. R ² represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms. It may be different. a represents an integer of 0 to 2. A) the alkyl (meth) acrylate having at least one hydrolyzable silyl group represented by the formula (1) and having an alkyl group having 8 or more carbon atoms is 2 to 50% by weight of all monomers. 100 parts by weight (solid content) of a vinyl copolymer (A), which is a copolymer obtained by copolymerizing the polymer, 0.001 to 10 parts by weight of a curing catalyst (B), and 6 or more carbon atoms A saturated hydrocarbon, an alicyclic hydrocarbon having 6 or more carbon atoms, at least one hydrocarbon organic solvent selected from aromatic hydrocarbons having 9 or more carbon atoms, and another organic solvent, Mixed organic solvent (C) 1 containing 50% by weight or more of hydrocarbon organic solvent
It is a curable composition for paint containing 0 to 500 parts by weight.

The vinyl copolymer, which is the component (A) of the curable composition for paints of the present invention, has a main chain composed of a vinyl copolymer chain, and has a carbon atom at the terminal and / or side chain of the main chain. An atom represented by the above general formula (1);

[0012]

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(Wherein R ¹ is a hydrogen atom or a group having 1 to 1 carbon atoms)
Represents 10 alkyl groups, and when there are plural alkyl groups, they may be the same or different. R ² represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms. It may be different. a represents an integer of 0 to 2. A) the alkyl (meth) acrylate having at least one hydrolyzable silyl group represented by the formula (1) and having an alkyl group having 8 or more carbon atoms is 2 to 50% by weight of all monomers. It is a copolymer obtained by copolymerizing a polymer.

Here, that the main chain is composed of a vinyl copolymer chain is defined as a polymerizable C ＝ C such as a vinyl group and a vinylidene group.
It means that a copolymer block of a compound having a bond and another compound constitutes a main chain of the vinyl copolymer (A).

The terminal of the main chain and / or the carbon atom of the side chain has at least one hydrolyzable silyl group represented by the general formula (1). As described above, at least one hydrolyzable silyl group may be present in one molecule as described above, but from the viewpoint of providing sufficient curability and relaxing internal stress, two to ten hydrolyzable silyl groups are present. Is preferred.

In the above general formula (1), R ¹ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. When a plurality of R ¹ are present, they may be the same or different. . As the alkyl group having 1 to 10 carbon atoms,
For example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an isopentyl group, an isohexyl group and the like can be mentioned. Among them, an alkyl group having 1 to 4 carbon atoms is preferable. When the carbon number of the alkyl group exceeds 10, the hydrolyzability of the hydrolyzable silyl group is reduced.

R ² is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or 7 carbon atoms.
Represents 10 to 10 aralkyl groups, and when there are a plurality of R ² , these may be the same or different. Among these, an alkyl group is preferable because the resulting curable composition for coatings has excellent curability.

Examples of the alkyl group having 1 to 10 carbon atoms include the same alkyl groups as those described above for R ^1.
Examples of the aryl group include a phenyl group, a tolyl group, and a xylyl group. Examples of the aralkyl group having 7 to 10 carbon atoms include a benzyl group, a cinnamyl group,
Examples include a phenethyl group and a styryl group. When the number of carbon atoms in the hydrocarbon group represented by R ² exceeds 10, the hydrolyzability of the hydrolyzable silyl group decreases.

A represents an integer of 0 to 2;
(OR ¹ ) is bonded to Si by 1-3,
These need not be the same. In particular, the hydrolyzable silyl group represented by the general formula (1) is represented by the following general formula (3);

[0020]

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(Wherein R ¹ , R ² and a are the same as those described above) and bonded to a carbon atom, the coating film is excellent in water resistance, alkali resistance, acid resistance and the like. Is preferred. In order to obtain a curable composition for coatings having excellent curability, acid resistance, weather resistance, etc., the equivalent of a hydrolyzable silyl group in the vinyl copolymer (A) (hydrolysis represented by the general formula (1)) (G) of the vinyl copolymer (A) containing 1 mol of the reactive silyl group) is preferably 500 to 7000 g / mol, more preferably 550 to 5000 g / mol, and 650 to 4000 g / mol. More preferably, it is molar. The hydrolyzable silyl group equivalent is 500
If it is less than g / mol, the internal stress tends to increase, while if it exceeds 7000 g / mol, the curability tends to decrease.

The vinyl copolymer (A) is, for example,
It is obtained by copolymerizing a hydrolyzable silyl group-containing vinyl monomer (F) and a monomer (G) copolymerizable with the monomer (F). Examples of the hydrolyzable silyl group-containing vinyl monomer (F) include the following.

[0023]

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[0024]

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(Wherein R ¹ , R ² and a are the same as above, and R ⁵ represents a hydrogen atom or a methyl group).

[0026]

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[0027]

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(Wherein R ¹ , R ² , R ⁵ and a are the same as above, and n represents an integer of 1 to 12).

[0029]

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[0030]

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(Wherein R ¹ , R ² , R ⁵ , a and n are
Same as above. ).

[0032]

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[0033]

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(Wherein R ¹ , R ² , R ⁵ and a are the same as above, and q represents an integer of 0 to 20). In addition to the above compounds, (meth) acrylates having a hydrolyzable silyl group represented by the above general formula (1) at a terminal via a urethane bond or a siloxane bond, and the like can also be mentioned. These compounds may be used alone or in combination of two or more. Among these, the compounds represented by the above general formula (5), which are easy to handle, inexpensive, and do not generate reaction by-products, are preferred.

The amount of the hydrolyzable silyl group-containing vinyl monomer (F) to be used is preferably 5 to 60% by weight, more preferably 10 to 50% by weight, based on all monomers. When the amount of the hydrolyzable silyl group-containing vinyl monomer (F) is less than 5% by weight, the acid resistance of a coating film formed using the obtained curable composition for coating becomes insufficient. When the content exceeds 60% by weight, the storage stability of the curable composition tends to decrease.

The above copolymerizable monomer (G) includes:
For example, methyl (meth) acrylate, ethyl (meth)
Acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, cyclohexyl (meth)
Acrylate, 2-ethylhexyl (meth) acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) ) Acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) acrylate, perfluorocyclohexyl (meth) acrylate, (meth) acrylonitrile, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) ) Acrylate, (meth) acrylamide, α-ethyl (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acryl Amide, N- butoxymethyl (meth) acrylamide, Toagosei Chemical Industry Co., Ltd. of the macromonomer (AS-6, AN-6, AA-6, AB-6, A
K-5, etc.), isocyanate compounds such as m-TMI, β-isocyanatopropyl (meth) acrylate manufactured by Takeda Pharmaceutical Company; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate;
2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl vinyl ether, N-methylol (meth) acrylamide, 4-hydroxystyrene vinyl toluene, Alonix 5700, 4 manufactured by Toa Gosei Chemical Industry Co., Ltd. -Hydroxystyrene, Nippon Shokubai Chemical Co., Ltd. acrylate oligomer having a hydroxyl group at a terminal (HE-10, HE
-20, HP-1, HP-20), polypropylene glycol methacrylate (Blemmer PP) manufactured by NOF Corporation
Series), polyethylene glycol monomethacrylate (Blemmer PE series), polyethylene glycol polypropylene glycol methacrylate (Blemmer PEP series), polypropylene glycol monoacrylate (Blemmer AP-400), polyethylene glycol monoacrylate (Blemmer AE-35)
0) and glycerol monomethacrylate (Blemmer GLM); ε-caprolactone-modified hydroxyalkylvinyl copolymerizable compound obtained by reacting a hydroxyl group-containing vinyl compound with ε-caprolactone, a polycarbonate-containing vinyl compound manufactured by Daicel Chemical Industries, Ltd. Compound (H
A hydroxyl group-containing compound such as EAC-1); a condensation product of an α, β-ethylenically unsaturated carboxylic acid alkyl ester having a hydroxy group such as hydroxy (meth) acrylate with phosphoric acid or a phosphoric acid ester; Ethyl phosphate group-containing vinyl compound; (meth) acrylic acid derivative such as (meth) acrylate containing urethane bond or siloxane bond; styrene, α-methylstyrene, chlorostyrene, styrenesulfonic acid, 4-hydroxystyrene, vinyltoluene Aromatic hydrocarbon-based vinyl compounds such as maleic acid, fumaric acid, and itaconic acid; salts of these salts such as alkali metal salts, ammonium salts and amine salts; and unsaturated carboxylic acids such as maleic anhydride. Acid anhydrides, and alcohols having a linear or branched chain having 1 to 20 carbon atoms; Esters of unsaturated carboxylic acids such as diester or half ester; vinyl esters and allyl compounds such as vinyl acetate, vinyl propionate and diallyl phthalate; vinyl compounds containing an amide group such as vinyl pyridine and aminoethyl vinyl ether; itaconic acid diamide and croton Amide, maleic diamide, fumaric diamide, N-vinylpyrrolidone and other amide group-containing vinyl compounds; methyl vinyl ether, cyclohexyl vinyl ether, vinyl chloride, vinylidene chloride, chloroprene, propylene, butadiene, isoprene, fluoroolefin maleimide, N-vinyl Other vinyl compounds such as imidazole and vinyl sulfonic acid are exemplified. These may be used alone or in combination of two or more.

From the above copolymerizable monomer (G), from the viewpoint of solubility in the organic solvent used in the present invention, an alkyl (meth) acrylate having 8 or more carbon atoms in the alkyl group is used. The body must be used in a proportion of 2 to 50% by weight of the total monomers. When the above ratio is less than 2% by weight, the solubility in the organic solvent used in the present invention is reduced, while 50%
If the content is more than 10% by weight, the copolymerizability tends to decrease and the glass transition point tends to decrease too much.

The amount of the alkyl (meth) acrylate monomer having 8 or more carbon atoms in the alkyl group is preferably 3 to 40% by weight of the total monomer, more preferably 5 to 30% by weight. preferable.

Examples of the alkyl (meth) acrylate monomer having 8 or more carbon atoms in the alkyl group include, for example,
2-ethylhexyl (meth) acrylate, 3,3,5
-Trimethylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate and the like. Of these, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate and the like having 12 or more carbon atoms are preferable.

When a monomer having an amine, carboxylic acid, sulfonic acid, or phosphoric acid group is used as the copolymerizable monomer (G), the monomer is used to suppress a crosslinking reaction at the time of polymerization. It is preferable to control the amount to be 5% by weight or less of all monomers.

Examples of the copolymerizable monomer (G) include a hydroxyl group, an amide group, an amino group, a nitrile group, an isocyanate group, and a carboxylic acid, sulfonic acid or phosphoric acid sodium salt. When using a monomer having an inorganic salt of the above, from the viewpoint of solubility in the organic solvent used in the present invention, the amount used is 10% by weight or less of all monomers, and further 5% by weight or less. It is preferable to suppress it.

The component (A) has a unit of a vinyl monomer,
It is preferably about 50% by weight or more of the units constituting the main chain, more preferably about 60% by weight or more,
More preferably, it is about 80% by weight or more. Therefore,
In the component (A), a urethane bond, a siloxane bond, or the like may be partially contained in a main chain or a side chain.

That is, the content does not exceed 50% by weight of the component (A) for the purpose of improving the weather resistance, solvent resistance, impact resistance, etc. of the coating film formed using the obtained curable composition for coatings. Within the range, a monomer having a urethane bond, a urea bond, a siloxane bond, or the like may be used so as to be included in the main chain of the vinyl copolymer.

The vinyl copolymer (A) is composed of the hydrolyzable silyl group-containing vinyl monomer (F) and the monomer (G) copolymerizable with the monomer (F). For example,
JP-A-54-36395, JP-A-57-5595
Although it can be produced by the method described in JP-A No. 4 (1993) -4, etc., it is produced by a solution polymerization method using an azo radical polymerization initiator such as azobisisobutyronitrile (AIBN) from the viewpoint of ease of synthesis and the like. Is preferred.

The polymerization solvent used in the above solution polymerization method includes:
It is not particularly limited as long as it is non-reactive, for example,
Hydrocarbons such as toluene, xylene, n-hexane and cyclohexane; acetates such as ethyl acetate and butyl acetate; methanol, ethanol, isopropanol and n
Alcohols such as butanol; ethers such as ethyl cellosolve, butyl cellosolve, and cellosolve acetate; ketones such as methyl ethyl ketone, ethyl acetoacetate, acetylacetone, diacetone alcohol, methyl isobutyl ketone, and acetone.

The above-mentioned polymerization solvent may be used alone,
Species or more may be used in combination, but from the viewpoint of reducing the effect on the environment at the time of coating caused by the residual solvent, etc., a saturated hydrocarbon having 6 or more carbon atoms, an alicyclic having 6 or more carbon atoms. It is preferable to use, as a main component, at least one organic solvent selected from hydrocarbons and aromatic hydrocarbons having 9 or more carbon atoms.

As such an organic solvent, hexane,
Heptane, octane, nonane, decane, undecane, dodecane; cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, 1,2,2
4-trimethylcyclohexane, cycloheptane, cyclooctane, cyclododecane; isopropylbenzene,
Examples include ethyltoluene, trimethylbenzene, propylbenzene, butylbenzene, isobutylbenzene, isopropyltoluene, diethylbenzene, tetramethylbenzene, 4-tert-butyltoluene, diisopropylbenzene, and triethylbenzene. Exxon Chemical's Solvesso 100 and Solvesso 150
Can be suitably used as the above-mentioned polymerization solvent since each main component is composed of an aromatic hydrocarbon having 9 or more carbon atoms.

The molecular weight of the resulting vinyl copolymer (A) may be adjusted by using a chain transfer agent during the solution polymerization. Specific examples of the chain transfer agent include, for example, n-dodecyl mercaptan, tert-dodecyl mercaptan, n-butyl mercaptan, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, (CH ₃ O) ₃ Si-SS-Si
_{(OCH 3), (CH 3} O) 3 Si-S 8 -Si (OC
H ₃ ). These may be used alone or in combination of two or more.

When a chain transfer agent having a hydrolyzable silyl group such as γ-mercaptopropyltrimethoxysilane in the molecule is used, a hydrolyzable silyl group is added to the terminal of the main chain of the vinyl copolymer (A). Is preferable since it can be introduced. The use amount of such a chain transfer agent is preferably 10% by weight or less based on the vinyl copolymer (A).

The component (A) has a main chain substantially consisting of a vinyl copolymer chain. By changing the type of the monomer component constituting the copolymer chain, a wide range of resins from soft to hard can be obtained. It is possible to design

In addition, since the main chain of the component (A) is substantially composed of a vinyl copolymer chain, the weather resistance and the chemical resistance of a coating film formed using the obtained curable composition for paints are obtained. Etc. will be excellent. Further, since the hydrolyzable silyl group is bonded to the carbon atom, the coating film is excellent in water resistance, alkali resistance, acid resistance and the like.

The curing catalyst as the component (B) of the present invention is not particularly limited. Specific examples of the curing catalyst (B) include, for example, organic tin compounds such as dibutyltin dilaurate, dibutyltin maleate, dioctyltin dilaurate, dioctyltin dimaleate, tin octylate; phosphoric acid; monomethyl phosphate, monoethyl phosphate, monoethyl phosphate Butyl phosphate, monooctyl phosphate, monodecyl phosphate, dimethyl phosphate,
Phosphate esters such as diethyl phosphate, dibutyl phosphate, dioctyl phosphate, and didecyl phosphate; propylene oxide, butylene oxide,
Cyclohexene oxide, glycidyl methacrylate, glycidol, acrylic glycidyl ether, γ-
Glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, Cardura E manufactured by Yuka Shell Epoxy, Epicoat 828 manufactured by Yuka Shell Epoxy, Epicoat 1001 Reaction product of an epoxy compound such as the above with phosphoric acid and / or monophosphate;
Organic titanate compounds; organoaluminum compounds; organozinc compounds; maleic acid, adipic acid, azelaic acid,
Organic carboxylic compounds such as sebacic acid, itaconic acid, citric acid, succinic acid, phthalic acid, trimellitic acid and pyromellitic acid, and their acid anhydrides; dodecylbenzenesulfonic acid, paratoluenesulfonic acid, 1-naphthalenesulfonic acid , Organic sulfonic acid compounds such as 2-naphthalenesulfonic acid, and nitrogen-containing compounds containing these organic sulfonic acid compounds (for example, 1-amino-2-propanol, monoethanolamine, diethanolamine, 2- (methylamino) ethanol, Dimethylethanolamine, 2-
Amino-2-methyl-1-propanol, diisopropanolamine, 3-aminopropanol, 2-methylamino-2-methylpropanol, morpholine, oxazolidine, 4,4-dimethyloxazolidine, 3,4,4
Reaction products of acids and amines blocked with trimethyl oxazolidin (eg, NACUR from KING INDUSTRIES)
E5225, NACURE5543, NACURE59
25)); hexylamine, di-2-ethylhexylamine, N, N-dimethyldodecylamine, dodecylamine, 1,4-diazabicyclo [2.2.2] octane (DABCO), 1,8-diazabicyclo [5. 4.
0] amines such as undecene-7 (DBU), morpholine and diisopropanolamine; reactants of these amines with acidic phosphate esters; alkaline compounds such as sodium hydroxide and potassium hydroxide; benzyltriethylammonium chloride or bromide; Examples include quaternary ammonium salts such as tetrabutylammonium chloride and bromide, and phosphonium salts. The above curing catalysts may be used alone or in combination of two or more.

The amount of the component (B) used is 100 parts of the component (A).
It is 0.001 to 10 parts by weight with respect to part by weight,
It is preferably from 0.05 to 10 parts by weight. If the amount of the component (B) is less than 0.001 part by weight, the curability is reduced, and if it is more than 10 parts by weight, the appearance of the coating film is reduced. In addition, when the curable composition for paint contains the component (D),
The component (B) is used in the above ratio with respect to 100 parts by weight of the component (D) and the component (A).

In the curable composition for paints of the present invention, a mixed organic solvent (C) is used in addition to the vinyl copolymer (A) and the curing catalyst (B). This mixed organic solvent (C)
It is necessary that each of the component (A), the component (B) and the component (D) described below can be dissolved or stably dispersed.

The mixed organic solvent (C) includes a saturated hydrocarbon having 6 or more carbon atoms, an alicyclic hydrocarbon having 6 or more carbon atoms,
It comprises at least one hydrocarbon organic solvent selected from aromatic hydrocarbons having 9 or more carbon atoms and other organic solvents, and the content of the hydrocarbon organic solvent is 50% by weight or more. . As the hydrocarbon-based organic solvent, for example, a solvent used when solution-polymerizing the above-described component (A) is used.

The content of the hydrocarbon organic solvent is 60
% By weight or more, more preferably 70% by weight or more. Since the content of the hydrocarbon organic solvent in the mixed organic solvent (C) is 50% by weight or more, the influence on the environment at the time of coating is small, and the obtained coating film has excellent weather resistance, It becomes a curable composition for paint having self-recoating property and stain resistance.

If the content of the hydrocarbon-based organic solvent is less than 50% by weight, problems occur in odor during coating and in self-recoating property. Further, by adding a dehydrating agent or a specific solvent as another organic solvent, the storage stability and the like of the curable composition for a paint can be further improved.

Examples of the dehydrating agent include methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, methyl orthopropionate, ethyl orthopropionate, methyl orthobutyrate, and ethyl orthobutyrate;
Dimethoxymethane, 1,1-dimethoxyethane, 1,1
-Dimethoxypropane, 1,1-dimethoxybutane and the like. These dehydrating agents may be used alone,
Two or more kinds may be used in combination. Among these dehydrating agents, methyl orthoformate or methyl orthoacetate is preferred from the viewpoint of the dehydration effect. The dehydrating agent may be added during the polymerization of the vinyl copolymer (A) or may be added after the polymerization.

The content of such a dehydrating agent is preferably less than 50% by weight, more preferably less than 40% by weight, even more preferably less than 30% by weight in the total solvent. The amount is preferably 50 parts by weight or less, more preferably 30 parts by weight or less, and still more preferably 15 parts by weight or less, based on 100 parts by weight of the vinyl copolymer (A).

The amount of the mixed organic solvent (C) used is based on 100 parts by weight (solid content) of the vinyl copolymer (A).
10 to 500 parts by weight. However, when the amount of the mixed organic solvent (C) is large, defects such as waki (foaming phenomenon) easily occur in a coating film formed by using the obtained curable composition for a coating material. 10 to 70 parts by weight, preferably 10 to 50 parts by weight, more preferably 10 to 20 parts by weight, based on 100 parts by weight of the combined (A).

The curable composition for paints of the present invention may contain a silicon compound as the component (D) or a partially hydrolyzed condensate thereof in order to further increase stain resistance and hardness. That is, the second present invention further comprises the following curable composition for a paint, further comprising the following general formula (2):

[0062]

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(Wherein R ³ is a hydrogen atom, having 1 to 1 carbon atoms)
An alkyl group having 0, an aryl group having 6 to 10 carbon atoms, or
Represents an aralkyl group having 7 to 10 carbon atoms, and when a plurality of aralkyl groups are present, they may be the same or different. R ⁴ is
Represents an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms. When a plurality of aralkyl groups are present, they may be the same or different. b represents the integer of 0-2. At least one of the silicon compounds represented by the formula
It is a curable composition for paint containing 0.1 to 50 parts by weight of seed (D).

In the general formula (2), R ³ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms. ^{When a} plurality of ³ exist, they may be the same or different. Specific examples of the alkyl group of R ^{3 and} the like include, for example, those substantially similar to those exemplified in the description of R ^{2 in} the general formula (1).

R ⁴ is an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a group having 7 to 1 carbon atoms.
Represents an aralkyl group of 0, and when there are a plurality of R ^{4 s} , they may be the same or different. Specific examples of R ⁴ are substantially the same as those exemplified in the description of R ² as described above. Further, since b is an integer of 0 to 2, there are 2 to 4 (R ³ O) groups in the same molecule, but these (R ³ O) groups need not be the same.

Specific examples of the above silicon compound include, for example, tetramethyl silicate, tetraethyl silicate, tetra n-propyl silicate, tetra i-propyl silicate, tetra n-butyl silicate, tetra i
Tetraalkyl silicates such as -butyl silicate and tetra-t-butyl silicate; alkyls such as methyltrimethoxysilane, methyltriethoxysilane, octadecyltriethoxysilane, methyltrisec-octyloxysilane, methyltriisopropoxysilane and methyltributoxysilane Trialkoxysilane; aryltrialkoxysilane such as phenyltrimethoxysilane and phenyltriethoxysilane; alkyltriaryloxysilane such as methyltriphenoxysilane;
Examples include trialkoxysilanes such as glycidoxytrialkoxysilanes such as glycidoxypropyltrimethoxysilane, and triaryloxysilanes.

The partially hydrolyzed condensate of the silicon compound is not particularly limited. For example, water is added to the above tetraalkyl silicate, trialkoxysilane, triaryloxysilane, etc. to partially hydrolyze and condense. And those obtained by hydrolyzing the above tetraalkyl silicate in an alcohol-based solvent in the presence of an acidic substance and water. Specific examples of the partially hydrolyzed condensate of the silicon compound include, for example, MS manufactured by Colcoat Co., Ltd.
I51, ESI28, ESI40, HAS-1, HAS
-10, partially hydrolyzed condensates of tetraalkyl silicates such as MS51 and MS56 manufactured by Mitsubishi Chemical Corporation; and partially hydrolyzed condensates of trialkoxysilanes such as AFP-1 manufactured by Shin-Etsu Chemical Co., Ltd.

The other component (D) includes the following:
For example, MS56S manufactured by Mitsubishi Chemical Corporation; silicate 40, silicate 45, silicate 48 manufactured by Tama Chemical Company, FR
3: Colcoat ESi40, ESi48 and the like. The component (D) may be used alone or in combination of two or more. The compatibility with the component (A), the curability of the curable composition for paint obtained, and the curing of the paint for paint. From the viewpoint that the hardness of the coating film formed using the conductive composition is increased, the fixation of contaminants is suppressed,
8, MS51, MS56, tetramethylsilicate such as HAS-1 and the like, and a partially hydrolyzed condensate of tetraethylsilicate are preferable.

The silicon compound or its partially hydrolyzed condensate (D) has a weight average molecular weight of 500 or more.
It is preferably at least 750. Weight average molecular weight of 50
If it is less than 0, the effect of stain resistance may be small.
Among the components used in component (D), MS5
6, MS56S, silicate 45, silicate 48, F
Those having a weight average molecular weight of 750 or more, such as R3, ESi48, and HASI, are more preferable.

The amount of the component (D) is 0.1 to 50 parts by weight, preferably 0.1 to 40 parts by weight, based on 100 parts by weight of the solid content of the component (A). Further, in order to increase the stain resistance, 2 to 40 parts by weight is more preferable,
5 to 40 parts by weight are more preferred. If the amount of the component (D) exceeds 50 parts by weight, the compatibility with the component (A) may be reduced, or the impact resistance of the curable composition for coating material may be reduced.

In order to improve the adhesion to the base, the component (E) can be added to the curable compositions for paints of the first and second inventions. That is, the third invention comprises the curable composition for paints of the first and second inventions, further comprising aminosilane, epoxysilane, a reaction product of aminosilane, and a reaction product of epoxysilane. It is a curable composition for paint containing at least one compound selected from the group.

The aminosilane is not particularly restricted but includes, for example, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminopropylmethyldimethoxysilane, aminopropylethyldiethoxysilane, [3- (2-aminoethyl) aminopropyl ] Trimethoxysilane, [3- (2-aminoethyl) aminopropyl] triethoxysilane, [3- (2-aminoethyl) aminopropyl] methyldimethoxysilane, [3
-(2-aminoethyl) aminopropyl] ethyldiethoxysilane and the like.

The above-mentioned epoxysilane is not particularly restricted but includes, for example, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, glycidoxypropylmethyldimethoxysilane, glycidoxypropylethyldiethoxysilane, β ( 3,4-epoxycyclohexylpropyl) ethyltrimethoxysilane, β (3,4-epoxycyclohexylpropyl) ethyltriethoxysilane, β (3,4-epoxycyclohexylpropyl) ethylmethyldimethoxysilane, β
(3,4-epoxycyclohexylpropyl) ethylethyldiethoxysilane and the like.

The reaction product of aminosilane and epoxysilane is obtained by reacting such that the equivalent ratio of amino group to epoxy group is 0.5 to 3.0, preferably 0.7 to 2.5. Is preferred.

Component (E) is used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the solid content of component (A). Parts by weight, and more preferably 5 to 10 parts by weight. If the amount of the component (E) exceeds 10 parts by weight, the compatibility with the component (A) may be reduced, or the impact resistance of the curable composition for coating material may be reduced.

The first, second and third curable compositions for paints of the present invention (hereinafter simply referred to as “curable compositions for paints”) may be used in order to further improve curability. And an amino resin such as a melamine resin, a urea resin, and a guanamine resin may be appropriately added.

The amino resin is preferably used in an amount of 30 parts by weight or less, more preferably 15 parts by weight or less, further preferably 5 parts by weight or less, based on 100 parts by weight of the resin solid content of the curable composition to be added. If the amount of the amino resin exceeds 30 parts by weight, the acid resistance tends to decrease.

For the same purpose, a compound having two or more isocyanate groups and / or blocked isocyanate groups in one molecule can be added. These resins are preferably 30 parts by weight or less, more preferably 20 parts by weight or less, still more preferably 10 parts by weight or less, based on 100 parts by weight of the resin solid content of the curable composition to be added. When the use amount of the above compound exceeds 30 parts by weight, the stability of the curable composition for coating tends to decrease.

The weatherability can be further improved by blending a weatherability improver such as an ultraviolet absorber and a light stabilizer to the curable composition for coatings. Further, by using the ultraviolet absorber and the light stabilizer together, the weather resistance can be more effectively improved.
The ultraviolet absorber is not particularly limited, and examples thereof include benzophenone-based, triazole-based, phenylsalicylate-based, diphenylacrylate-based, and acetophenone-based ones. These may be used alone,
Two or more may be used in combination.

The light stabilizer is not particularly restricted but includes, for example, bis (2,2,6-tetramethyl-4-piperidyl) sebacate and bis (1,2,2,6,6-pentamethyl-4-piperidyl). ) Sebacate, 2- (3,5-t)
tert-butyl-4-hydroxybenzyl) -2-n-
Bis (1,2,2,6,6-pentamethyl-4-piperidyl) tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxy butylmalonate Rate, tetrakis (1,2,2,
6,6-pentamethyl-4-piperidyl) -1,2,2
3,4-butanetetracarboxylate and the like. These may be used alone or in combination of two or more.

The amount of the ultraviolet absorbent used is 0.1 to 100 parts by weight of the resin solid content of the curable composition for paint.
It is preferably from 10 to 10 parts by weight, more preferably from 1 to 5 parts by weight. The light stabilizer is used in an amount of 0.1 to 10 parts by weight per 100 parts by weight of the resin solid content of the curable composition for coating.
Part by weight is preferable, and 1 to 5 part by weight is more preferable.

In addition, the following curable composition for paints may be appropriately added to the above-mentioned curable composition for paints, whereby the composition can be used as an enamel paint.

Examples of these additives include titanium oxide, ultramarine, navy blue, zinc white, red bengal, graphite, lead white,
Inorganic pigments such as carbon black, transparent iron oxide, and aluminum powder; organic pigments such as azo pigments, triphenylmethane pigments, quinoline pigments, anthraquinone pigments, and phthalocyanine pigments; diluents, anti-sagging agents, and rheology control agents Additives such as a cellulose acetate butyrate; a resin such as an epoxy resin, a vinyl chloride resin, a fluororesin, a chlorinated polypropylene, a chlorinated rubber, a polyvinyl butyral, and a polysiloxane.

The curable composition for a coating material of the present invention can be applied to a target substrate by various conventional methods such as dipping, spraying, brushing, a roll coater method and a flow coater method. After being applied, it is usually cured at room temperature as it is or by baking at about 30 ° C. or more.

The thickness of the coating film on the object to be coated cannot be specified unconditionally because it varies depending on the application. However, in the case of undercoating or intermediate coating, the thickness of the coating film is 5 to 30 in view of concealability and the like.
In the case of overcoating, the thickness of the coating film is preferably in the range of 20 to 50 µm from the viewpoint of durability and the like.

The curable composition for paints of the present invention may be, for example,
Metal, ceramic, glass, cement, ceramic moldings,
Used as a paint for undercoating, intermediate coating or topcoating of buildings, bridges, home appliances, industrial equipment, etc. made of plastic, wood, paper, fiber, etc. Is done.

[0087]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Synthesis Example Synthesis of Vinyl Copolymer (A) In a reactor equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen gas inlet tube and a dropping funnel, first, raw material 2 shown in Table 1 below was placed. After charging and raising the temperature to 110 ° C. while introducing nitrogen gas, the mixed solution of the raw material 1 was dropped at a constant speed over 5 hours.

Next, the mixed solution of the raw material 3 was dropped at a constant speed over 1 hour, subsequently stirred at 110 ° C. for 2 hours, and cooled to room temperature. Finally, the mixed solution of the raw material 4 was added and stirred.

The solid content concentration of the obtained vinyl copolymer (A) and the number average molecular weight of the copolymer measured by gel permeation chromatography (GPC) are also shown in Table 1. AIBN in Table 1 is azobisisobutyronitrile as a polymerization initiator, A-174 is 3-methacryloxypropyltrimethoxysilane manufactured by Nippon Unicar, and V-59 is 2 manufactured by Wako Pure Chemical Industries. , 2'-azobis (2-methylbutyronitrile).

[0091]

[Table 1]

Examples 1-4 and Comparative Examples 1-2 A leveling agent (manufactured by Kusumoto Kasei Co., Ltd.) was added to 100 parts by weight of the resin solution containing the vinyl copolymer (A) obtained in the above synthesis example.
L-1984-50) as an ultraviolet absorber, 2 parts by weight of Tinuvin 384 manufactured by Ciba-Geigy,
1 part by weight of Tinuvin 123 manufactured by Ciba-Geigy was added as a light stabilizer.

Next, the components (B) and (E) shown in Table 2
The components were added at the solid content ratio shown in Table 2, followed by Shell Japan Shelsol S (90% by weight or more of a linear alkane having 9 to 14 carbon atoms) / Solvesso 100 = 50.
/ 50 and adjusted to a viscosity of about 20 to 25 seconds with a Ford cup to obtain a clear paint.

In Table 2, the component (B) -1 is dibutyltin dibutyl maleate, the component (E) -1 is aminosilane (A-1120 manufactured by Nippon Unicar),
(E) -2 component is aminosilane (manufactured by Nippon Unicar Co., Ltd.)
A-1100) and bisphenol A diglycidyl ether at a molar ratio of 2: 1.

Next, a coated plate obtained by coating an epoxyamide-based cationic electrodeposition primer for automobiles and an intermediate coated surfacer on a mild steel plate subjected to a degreasing treatment and a phosphate conversion treatment was used as a test piece. The resin coating was applied to a dry film thickness of about 15 μm.

After baking at 140 ° C. for 20 minutes,
The surface was polished with # 800 sandpaper, and the clear coating was applied by spray coating so that the dry film thickness was about 40 μm. After setting for 5 minutes,
After baking at 70 ° C. for 30 minutes, the coated plate was cured at 23 ° C. and a relative humidity of 55% to form a cured product (coating film) on the surface.

[0097]

[Table 2]

Examples 5 to 12 and Comparative Example 3 Using the resin solution containing the vinyl copolymer (A) obtained in the above synthesis example, PVC (the ratio of pigment to the total solid content) was used.
Was dispersed in titanium oxide (CR-90, manufactured by Ishihara Sangyo Co., Ltd.) so that the coating solid content was 40% by weight and the coating solid content was 60% by weight to prepare a white enamel. Dispersion was performed for 2 hours on a paint shaker using glass beads.

Next, the obtained white enamel was subjected to Shellsol S / Solvesso 100 = 50/5 manufactured by Shell Japan.
The composition was diluted with 0 (weight ratio) to prepare a composition having a solid content of 45% by weight. Next, a commercially available synthetic resin emulsion-based multi-layer finish coating material was applied on the slate such that the film thickness after leaving at room temperature for one day was 3 mm. Then, after allowing to stand at room temperature for one day, the components (B), (D), and (E) shown in Table 3 are blended with the above-mentioned white enamel composition at a solid content shown in Table 3. The obtained product was applied with a brush so that the dry film thickness became 50 μm.

The component (B) -2 shown in Table 3 was dibutyltin dioleyl maleate, and the component (D) -1 was
Partially hydrolyzed condensate of tetramethyl silicate (MSI51 weight average molecular weight: about 500, manufactured by Colcoat),
The component (D) -2 is a partially hydrolyzed condensate of tet-ethyl silicate (MSi40 manufactured by Colcoat Co., Ltd., weight average molecular weight: about 700), and the component (D) -3 is a partially hydrolyzed condensate of tetramethyl silicate (Mitsubishi Chemical Corporation). MS5
6S weight average molecular weight: about 1500-2000),
The component (D) -4 is a partially hydrolyzed condensate of tetramethyl silicate and tetraethyl silicate (FR-3 weight average molecular weight: about 1500 to 200 manufactured by Tama Chemical Co., Ltd.).
The components (0) and (D) -5 are partially hydrolyzed condensates of tetramethylsilicate (silicate 45 weight average molecular weight: about 1000, manufactured by Tama Chemical Co., Ltd.), and the component (E) -3 is aminosilane (manufactured by Nippon Unicar Co., Ltd., A -1122) and γ-glycidoxypropyltrimethoxysilane (A-187 manufactured by Nippon Unicar) at a molar ratio of 1: 2.2.

[0101]

[Table 3]

Evaluation Method Appearance, self-recoating property, adhesion, and the like of the coating films obtained in Examples 1 to 12 and Comparative Examples 1 to 3
Water resistance secondary adhesion, accelerated weather resistance, stain resistance and hydrophilicity were evaluated by the following methods. The results are shown in Tables 4 and 5 below.

Appearance The gloss and sharpness were visually evaluated comprehensively and displayed according to the following criteria. ：: good △: normal ×: bad

Self-recoating property One day later, the curable composition for paint was applied again under the same conditions as the first time on the obtained article to be coated, set at 23 ° C., and evaluated. Indicated by. ：: No abnormality △: Partially lifting ×: Full surface lifting

Adhesion Test method (2 m) according to JIS K 5400
(m × 2 mm, 25 pieces). Water Resistance Secondary Adhesion The obtained coated article was immersed in warm water at 40 ° C. for 30 days, and the adhesion was evaluated in the same manner as in the case of the above.

Accelerated Weathering In accordance with JIS K 5400, an accelerated weathering test was performed using a sunshine carbon arc lamp type weathering tester (manufactured by Suga Test Instruments Co., Ltd.) under the following conditions. Test conditions: Black panel temperature: 63 ± 3 ° C., rainfall for 18 minutes in 120 minutes, and visual evaluation after 1500 hours, indicated by the following criteria. ：: No abnormality △: Decrease in gloss and adhesion of water marks are clearly observed

At the beginning of the exposure, the lightness represented by the L * a * b * color system was measured with a colorimeter (CR300 manufactured by Minolta Co., Ltd.). After three months, the brightness was measured similarly. The absolute value (−ΔL value) of the difference between the lightness after exposure and the lightness before exposure was used as a measure of contamination.
The smaller the absolute value, the better the stain resistance, and the larger the absolute value, the more dirty.

Hydrophilic Contact Angle Measuring Machine (Model CA-S150, Kyowa Interface Science Co., Ltd.)
Was evaluated by measuring the contact angle with water after 3 months of outdoor exposure at 45 ° on the south side in Hyogo Ward, Kobe City. The smaller the value, the higher the hydrophilicity.

[0109]

[Table 4]

[0110]

[Table 5]

As is clear from the results shown in Tables 4 and 5, the coating films formed using the curable coating compositions obtained in Examples 1 to 12 are excellent in appearance, adhesion and the like. It has excellent balance of coating film properties such as weather resistance and self-recoating property, and also has excellent stain resistance.

[0112]

The first, second and third curable compositions for top coats of the present invention are excellent in self-recoating property and good in appearance and adhesion of the formed coating film, and
Since it has an excellent balance of coating properties such as weather resistance and stain resistance, it can be used for, for example, buildings and bridges made of metals, ceramics, glass, cement, ceramic moldings, plastics, wood, paper, fibers, etc. It can be used as an undercoat, an intermediate coat, a topcoat, or the like for articles, home appliances, industrial equipment, and the like, and can be particularly suitably used for a topcoat. The object to be coated on which the curable composition for a paint is applied has excellent characteristics as described above.

Claims (5)

[Claims] 1. The main chain comprises a vinyl copolymer chain, and the terminal and / or the side chain carbon atom of the main chain has the following general formula (1): (In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, when there are a plurality may .R ² be different even if the same is a hydrogen atom, C 1 -C -10
Represents an alkyl group, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms, and when two or more are present, they may be the same or different. a is 0
Represents an integer of 2. ) Having at least one hydrolyzable silyl group and having an alkyl group having 8 or more carbon atoms, wherein alkyl (meth) acrylate is 2 to 5 of all monomers.
100 parts by weight (solid content) of a vinyl copolymer (A) which is a copolymer obtained by copolymerizing 0% by weight of a monomer;
0.001 to 10 parts by weight of the curing catalyst (B), and a saturated hydrocarbon having 6 or more carbon atoms, an alicyclic hydrocarbon having 6 or more carbon atoms, or an aromatic hydrocarbon having 9 or more carbon atoms. A mixture of at least one kind of hydrocarbon organic solvent and another organic solvent, wherein the hydrocarbon organic solvent contains 50% by weight or more of 10 to 500 parts by weight of a mixed organic solvent (C). Curable composition for paint. 2. The curable composition for paint according to claim 1,
Furthermore, the following general formula (2): (Wherein, R ³ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or 7-1.
Represents an aralkyl group of 0, and when two or more aralkyl groups are present, they may be the same or different. R ⁴ has 1 to 1 carbon atoms
An alkyl group having 0, an aryl group having 6 to 10 carbon atoms, or
Represents an aralkyl group having 7 to 10 carbon atoms, and when a plurality of aralkyl groups are present, they may be the same or different. b is 0
Represents an integer of ２2. At least one (D) of the silicon compound represented by the formula (1) or a partially hydrolyzed condensate thereof.
A curable composition for a paint, comprising 1 to 50 parts by weight. 3. The silicon compound or its partially hydrolyzed condensate (D) is tetramethyl silicate or its partially hydrolyzed condensate, and has a weight average molecular weight of 500 or more. Curable composition for paints. 4. The curable composition for a coating material according to claim 1, further selected from the group consisting of aminosilane, epoxysilane, a reaction product of aminosilane, and a reaction product of epoxysilane. A curable composition for paints comprising 0.1 to 10 parts by weight of at least one compound (E). 5. An object to be coated as a clear coat and / or an enamel coat by applying a coating material on the surface of a substrate, wherein the coating material is a coating material according to claim 1, 2, 3, or 4. An article to be coated, characterized by containing a hydrophilic composition as a main component.