JPH07286126A - Binder for inorganic/organic combined-coating coating agent - Google Patents

Abstract

PURPOSE:To provide a binder for an inorganic/organic-combined coating agent consisting of a hydrolyzate of a fluorine-containing copolymer containing a hydrolyzable silyl and a siloxane compound and excellent in hardness and warm water, stain, crack and weather resistances. CONSTITUTION:This binder is composed of (A) a hydrolyzate of fluorine- containing copolymer having a hydrolyzable silyl and (B) a siloxane compound {e.g. a compound of formula I [R<1> to R<4> are each is a 1-4C alkyl; (n) is 2-15]}. The fluorine-containing copolymer is obtained by copolymerizing, e.g. a vinyl monomer having a hydrolyzable silyl and expressed by formula II [R<1> is H, an alkyl, etc.; R<2> is a halogen, phenoxy, etc.; (a) is 0-2] with fluorolefins. A hydrolyzable silyl-containing vinyl ethers such as triethoxysilylethyl vinyl ethers are preferably used as the vinyl monomer and vinyl fluoride, etc., is preferably used as the fluoroolefins. Furthermore, the component A is preferably combined with the component B together with a hydrolyzate of a hydrolyzable silyl- containing acrylic copolymer.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention can form a film by heating at room temperature or a relatively low temperature, and can form a film excellent in hardness, hot water resistance, stain resistance, crack resistance and weather resistance. The present invention relates to a binder for an inorganic / organic composite coating material.

[0002]

2. Description of the Related Art Conventionally, with respect to film formation, a method of using a partial hydrolyzate (polyalkoxysiloxane) of an alkoxy silicate having an alkyl group having 1 to 4 carbon atoms as a film forming agent (inorganic coating system), organosilane , A method of obtaining a film-forming agent by a combination of a hydrolyzate of organosilane, a partial condensate, a partial cocondensate and a silyl group-containing acrylic resin, or other acrylic resin, epoxy resin (inorganic / organic coating system) )
(JP-A-3-115479), anciently, a mixture of polyacetal resin and polysilicic acid,
A method of using a heated reaction product of a carboxyl group-containing acrylic resin and an alkyl silicate in the presence of an acid catalyst, a heated mixture of a polyvinyl acetal and an alkyl silicate, etc. as a film forming agent (inorganic / organic coating system), fluorine-containing copolymer A method of using a polymer as a film forming agent (organic coating system), and the like are known.

[0003]

The above method is widely known. However, the coating is hard, and cracks are likely to occur during heating during coating formation and after coating formation, and only a thin film having a dry film thickness of about 1 μm or less can be obtained. It has the drawback of not being practical, and the above method has emerged as a solution to the drawbacks of the above method, but the crack resistance improves as the amount of organic resin components increases, but the weather resistance decreases. It happened and was not enough to satisfy both. The above method is mainly a means for determining hardness and wear resistance, and has the same drawbacks as the above method. The above method is not an inorganic / organic composite, but has a feature that it is excellent in crack resistance and weather resistance. However, it has the drawback of being poor in stain resistance and hardness.

In view of such a situation, the inventors of the present invention have conducted extensive studies as a result of earnest studies to provide a binder for a coating agent having excellent hardness, warm water resistance, stain resistance, crack resistance and weather resistance. The invention was reached.

[0005]

That is, the binder for an inorganic / organic composite coating material of the present invention is obtained by mixing a hydrolyzate of a fluorocopolymer having a hydrolyzable silyl group with a siloxane compound. It is a mixture or is obtained by mixing a mixture of a hydrolyzate of a fluorocopolymer having a hydrolyzable silyl group and a hydrolyzate of an acrylic copolymer having a hydrolyzable silyl group with a siloxane compound. It is a mixture.

The present invention is described in detail below: "Fluorine-containing copolymer having hydrolyzable silyl group" in the present invention
Refers to a fluorocopolymer having at least one hydrolyzable silyl group in the side chain in one molecule. In order to synthesize such a fluorine-containing copolymer, (1) a hydrolyzable silyl group-containing vinyl monomer is copolymerized with a fluoroolefin, and (2) a hydrolyzable silyl group-containing chain transfer agent. In the presence of a hydrolyzable silyl group-containing vinyl monomer and fluoroolefin are copolymerized,
(3) A fluorine-containing copolymer having a reactive group such as a hydroxyl group, a carboxyl group, an epoxy group and an amino group, and a low functional group-containing functional group such as an epoxy group, an isocyanate group and an amino group capable of reacting with the reactive group. A method in which a hydrolyzable silyl group-containing compound having a molecular weight is reacted to introduce a hydrolyzable silyl group into the fluorine-containing copolymer can be effectively used.

In the present invention, the hydrolyzable silyl group is represented by the general formula (I)

[0008]

[Chemical 1](In the formula, R¹ Is a hydrogen atom, an alkyl group, an aryl group or
An aralkyl group, R ² Is a halogen atom, alkoxy
Group, substituted alkoxy group, acyloxy group, phenoxy group,
Mercapto group, amino group, iminooxy group or alkeny group
Is a ruoxy group, and a is an integer of 0, 1 or 2. )
A halosilyl group, an alkoxysilyl group, an acyl
Xysilyl group, phenoxysilyl group, mercaptosilyl
Group, aminosilyl group, iminooxysilyl group or alkene group
A reactive group such as a nyloxysilyl group that is easily hydrolyzed
This is what you call it.

The fluoroolefins used in the above method (1) or (2) include vinyl fluoride, vinylidene fluoride, trifluoroethylene, tetrafluoroethylene, bromotrifluoroethylene, chlorotrifluoroethylene and penta. Typical examples are fluoropropylene, hexafluoropropylene, and (per) fluoroalkyl trifluorovinyl ether (wherein the (per) fluoroalkyl group has 1 to 18 carbon atoms). Of these, selected from the group consisting of vinyl fluoride, vinylidene fluoride, trifluoroethylene, tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene and (per) fluoro (C ₃ -C ₄ ) alkyltrifluorovinyl ether. It is particularly preferred to use at least one. The amount of the fluoroolefins used is 10 to 10% of all the monomers used for producing the "fluorine-containing copolymer having a hydrolyzable silyl group".
70% by weight, preferably 20 to 60% by weight is suitable.

The hydrolyzable silyl group-containing vinyl monomer used in the above method (1) or (2) is a halosilyl group or an alkoxysilyl group represented by the general formula (I). , A vinyl monomer containing a functional group that is easily hydrolyzed, such as an acyloxysilyl group, a phenoxysilyl group, a mercaptosilyl group, an aminosilyl group, an iminooxysilyl group or an alkenyloxysilyl group.

Of these vinyl monomers, from the viewpoint of copolymerizability with fluoroolefins, the following general formulas (II) and (II
Vinyl monomers containing a hydrolyzable silyl group represented by I) or (IV), particularly vinyl ethers are preferable: R ¹ (X ¹ X ² ) SiY ¹ (II) R ¹ (X ¹ ) Si ( Y ¹ Y ² ) (III) R ¹ Si (Y ¹ Y ² Y ³ ) (IV) (In the formula, R ¹ has an olefinically unsaturated bond and is composed of a carbon atom, a hydrogen atom and, optionally, an oxygen atom. Represents an organic group, X ¹ and X ² are the same or different and each represents an organic group having no olefinic unsaturated group, and Y ¹ , Y 2
² and Y ³ are the same or different and each represent a hydrolyzable group).

Specific examples of R ¹ include a vinyl group, an allyl group, a butenyl group, a cyclohexenyl group and a cyclopentadienyl group, and may be a group having an ester bond of a terminal unsaturated acid. . Specific examples of X ¹ and X ² include a monovalent hydrocarbon group such as a methyl group, an ethyl group, a propyl group, a tetradecyl group, an octadecyl group, a phenyl group, a benzyl group and a tolyl group, or a halogen-substituted hydrocarbon group thereof. Is mentioned. Above Y ¹ , Y ²
Specific examples of Y ³ include an alkoxy group or an alkoxyalkoxy group such as a methoxy group, an ethoxy group, a butoxy group and a methoxyethoxy group; an acyloxy group such as a formyloxy group, an acetoxy group and a propionoxy group;
(CH _{3) 2,} oximes such as _{-ON = C (C 2 H 5} ) 2; -
NHCH _3, -NHC ₂ H _5, and a substituted amino group or an arylamino group such as -NH (C ₆ H ₅₎ can be mentioned.

Specific examples of the vinyl monomer include vinyltrimethoxysilane, vinyldimethoxysilane, vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinylmethyldiethoxysilane, vinyldiethylmethoxysilane and vinyltris (β-methoxyethoxy). Silane), vinyltriisopropenyloxysilane,
Vinyltris (dimethyliminooxy) silane, vinyltris (methylethyliminooxy) silane, vinyltrichlorosilane, vinyltriphenoxysilane, trimethoxysilylethylvinylether, triethoxysilylethylvinylether, methyldimethoxysilylethylvinylether, trimethoxysilylpropylvinylether, Triethoxysilylpropyl vinyl ether, etc. may be mentioned.

In the production of the "fluorine-containing copolymer having a hydrolyzable silyl group", in addition to the above preferable amount of the hydrolyzable silyl group-containing simple substance, allyltrimethoxy is used within a range not lowering the polymerization rate. Silane, γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane,
Monomers such as γ- (meth) acryloyloxypropyltriisopropenyloxysilane can be used in combination.

Further, in the production of the "fluorine-containing copolymer having a hydrolyzable silyl group", when the fluoroolefins and the vinyl monomer having a hydrolyzable silyl group are copolymerized with each other, Copolymerizable monomers can be used. Such monomers include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl caproate, vinyl caprate, vinyl caprylate, vinyl versatate, vinyl laurate or vinyl stearate. Chain or branched vinyl ester of aliphatic carboxylic acid, alicyclic carboxylic acid vinyl ester such as cyclohexanecarboxylic acid vinyl ester, benzoic acid vinyl ester, pt-butyl benzoic acid vinyl ester or salicylic acid vinyl ester Hydroxyalkyl vinyl ethers such as group-based carboxylic acid vinyl ester, hydroxyethyl vinyl ether, hydroxypropyl vinyl ether or hydroxybutyl vinyl ether, methyl vinyl ether, ethyl vinyl ether, propyl vinyl A linear or branched aliphatic or alicyclic vinyl ether such as ether, n-butyl vinyl ether, i-butyl vinyl ether, t-butyl vinyl ether or cyclohexyl vinyl ether, or an epoxy group such as glycidyl vinyl ether or glycidyl (meth) acrylate. Having monomers, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, monoethyl maleate, monobutyl maleate, monobutyl fumarate, monobutyl itaconic acid, monovinyl adipate, Monomers having a carboxyl group such as monovinyl sebacate, dimethylaminoethyl vinyl ether, dimethylaminopropyl vinyl ether, N-dimethylaminoprolyl (meth) acrylamide, dimethylamino Vinyl monomers containing such basic nitrogen chill (meth) acrylate, ethylene, propylene, butene -
1 or α-olefins such as hexene-1, halogenated olefins other than the above-mentioned fluoroolefins such as vinyl chloride or vinylidene chloride, aromatic vinyl monomers such as styrene, α-methylstyrene or vinyltoluene, methyl (Meth) acrylic acid esters such as phosphoric acid esters of (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, β-hydroxyethyl (meth) acrylate, and further (meth) Acrylonitrile, (meth) acrylamide, N-methylol (meth)
There are monomers such as acrylamide or N-butoxymethyl (meth) acrylamide.

Among these, from the viewpoint of solubility of the obtained polymer in a solvent, vinyl esters of aliphatic carboxylic acids having 3 to 23 carbon atoms, vinyl esters of alicyclic carboxylic acids, and vinyl aromatic carboxylates. It is preferable to contain one kind or a mixture of two or more kinds selected from esters in an amount of 10% by weight or more based on all monomers.

More preferably, a linear or branched aliphatic or alicyclic vinyl ether such as methyl vinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether or cycloalkyl vinyl ether is contained in an amount of 5% by weight based on all monomers. When it is contained in the above amount, the desired polymer can be efficiently obtained.

Next, the chain transfer agent containing a hydrolyzable silyl group used in the above method (2) is originally used for controlling the molecular weight of the copolymer, but at the same time, it is a fluoroolefin. It is used for the purpose of introducing a hydrolyzable silyl group to the terminal of the molecular chain of the copolymer, and is preferably used in combination with the vinyl monomer containing the hydrolyzable silyl group, that is, in the above (2). It is preferably used in the method. Specific examples of such a hydrolyzable silyl group-containing chain transfer agent include γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane or γ. -Mercaptopropyltriisopropenyloxysilane and the like.

The hydrolyzable silyl group-containing vinyl monomer and the hydrolyzable silyl group-containing chain transfer agent are used as resin solids from the viewpoints of compatibility with the siloxane compound of the obtained polymer, curability and stability. The amount of the hydrolyzable silyl group introduced per 1000 g is preferably in the range of 0.1 to 3.0 mol.

The above-mentioned monomers are used, if necessary, by using a radical polymerization initiator in the presence of the chain transfer agent,
Polymerization may be carried out by a batch-type, semi-continuous type or continuous type operation by making full use of known techniques such as bulk polymerization or solution (pressure) polymerization. Examples of such radical polymerization initiators include diacyl peroxides such as acetyl peroxide or benzoyl peroxide, ketone peroxides such as methyl ethyl ketone peroxide or cyclohexanone peroxide, hydrogen peroxide, t-butyl hydroperoxide, or cumene hydrofluoride. Hydroperoxides such as peroxides, dialkyl peroxides such as di-t-butylperoxide or dicumyl peroxide, t-butylperoxyacetate or t-butylperoxyacetate or t-butylperoxypiparate Such as alkyl peroxyesters, azo initiators such as azobisisobutyronitrile or azobisisovaleronitrile, or ammonium persulfate or potassium persulfate. Such as persulfates are used, the reducing agent of sodium bisulfite or such inorganic sodium metabisulfite, or such organic reducing agent cobalt naphthenate or dimethylaniline may also be used if necessary.

As the copolymerization reaction method, various known methods as described above can be used, and among them, solvent pressure polymerization is simple. As the solvent used at that time, a hydrocarbon system such as toluene, xylene, cyclohexane, n-hexane or octane, an ester system such as methyl acetate, ethyl acetate or butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone or methyl. Ketones such as amyl ketone, amides such as dimethylformamide or dimethylacetamide, alcohol solvents such as methanol, ethanol, i-propanol, n-butanol, i-butanol, sec-butanol or ethylene glycol monoalkyl ethers, or these solvents. Although a mixture such as a mixture can be used, it is preferable to use a solvent containing an alcohol solvent from the viewpoint of improving the storage stability of the resulting copolymer and the miscibility with water during hydrolysis.

Further, in the copolymerization reaction, lauryl mercaptan, octyl mercaptan,
Various chain transfer agents such as 2-mercaptoethanol or α-methylstyrene dimer can also be used.

The reaction temperature during the copolymerization reaction is -2.
The temperature in the range of 0 ° C. to 130 ° C. is suitable, and the pressure in the initial stage of the reaction is in the range of 1 to 100 Kg / cm ² , preferably 5 to 60 Kg / cm ² .

The number average molecular weight (Mn) of the fluorine-containing copolymer containing a hydrolyzable silyl group thus obtained
Is 1,000 to 3 from the viewpoint of film-forming property and pot life.
The range of 10,000 is preferable.

The method (3) above utilizes the reactivity of the isocyanate group, hydroxyl group, carboxylic acid group, epoxy group, amino group, etc. of the known fluorine-containing copolymer containing no hydrolyzable silyl group. The hydrolyzable silyl low molecular weight compound having a reactive group capable of reacting with the group is appropriately introduced to introduce a hydrolyzable silyl group into the fluorine-containing copolymer. Specific examples of the compound include isocyanate alkylalkoxysilanes such as γ-isocyanate propylmethyldimethoxysilane, alkoxysilyl isocyanates such as trimethoxysilyl isocyanate, and alkoxysilyl anhydrides such as 4-trimethoxysilyltetrahydrophthalic anhydride. , Γ-glycidoxypropylmethyldiethoxysilane and other glycides Xyalkylalkoxysilanes, γ-aminopropyltrimethoxysilane and other aminoalkylalkoxysilanes, γ-chloropropyltrimethoxysilane and other chloroalkylalkoxysilanes, γ-mercaptopropyltrimethoxysilane and other thioalkylalkoxysilanes However, isocyanate alkylalkoxysilane, alkoxysilylisocyanate and the like are preferable from the viewpoints of handleability, ease of reaction control, odor and corrosive substances. Regarding the number of carbon atoms in the alkoxy, an alkoxy having 1 to 8 carbon atoms can be used, but methoxy, ethoxy, propoxy, butoxy and the like having 1 to 4 carbon atoms are points of reaction rate and evaporation rate of hydrolysis by-products. Is preferred.

Further, the "acrylic copolymer having a hydrolyzable silyl group" in the present invention is compatible with the above-mentioned fluorocopolymer and has at least one hydrolyzable silyl group in one molecule. The acrylic copolymer contained in the side chain is referred to. Specifically, it is preferably a copolymer containing as an essential component a (meth) acrylic acid alkyl ester having 2 to 4 carbon atoms and a monomer containing a hydrolyzable silyl group copolymerizable with the monomer. And the weight average molecular weight is 3,000 to 10
10,000, preferably 6,000 to 80,000.

The alkyl ester of (meth) acrylic acid having 2 to 4 carbon atoms is a component for uniformly compatibilizing the above-mentioned fluorine-containing copolymer, and the content thereof is 5 to 80% by weight, particularly preferably 20. Is about 70% by weight. If the content is too low, the compatibility with the fluorocopolymer will be reduced, and as a result, the transparency, gloss and sharpness of the clear coating film will tend to be reduced. The hardness of the film tends to decrease, and the weather resistance tends to decrease.

Examples of the alkyl ester of (meth) acrylic acid having 2 to 4 carbon atoms include ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, and acrylic. Acid isobutyl, isobutyl methacrylate,
There are tert-butyl acrylate, tert-butyl methacrylate and the like.

The amount of the hydrolyzable silyl group introduced in the hydrolyzable silyl group-containing monomer is less than 0.001 per 1,000 g of the resin solid content from the viewpoint of compatibility, curability and storage stability of the resulting polymer. It is preferably used in an amount of 1 to 3.0 mol. If the content is too low, not only the hydrolysis operation cannot be sufficiently controlled, but also the compatibility with the siloxane compound becomes insufficient. When the content increases,
The burnability of the coating film tends to decrease. As these hydrolyzable silyl group-containing monomers, used for the copolymerization of the hydrolyzable silyl group-containing fluorocopolymer, vinylalkoxysilane, vinylalkylalkoxysilane,
Monomers such as alkoxysilyl vinyl ether, allylalkoxysilane and γ-acroylalkylalkoxysilane are used as appropriate.

The most convenient method for introducing a hydrolyzable silyl group into an acrylic copolymer is to copolymerize an acrylic monomer with a hydrolyzable silyl group-containing monomer.
This method is not necessarily the only one. Utilizing a reactive group such as a hydroxyl group, a carboxylic acid group, an amino acid group or an epoxy group of a known acrylic copolymer not containing a hydrolyzable silyl group, a low molecular weight compound having a hydrolyzable silyl group which reacts with these You may react. The specific example is the same as the method (3) for producing the fluorine-containing copolymer.

The acrylic copolymer having a hydrolyzable silyl group includes (meth) acrylic acid in addition to the above-mentioned two types of monomers.
Acid monomers such as itaconic acid, fumaric acid and maleic anhydride, (meth) acrylic acid esters such as methyl (meth) acrylate, 2-ethylhexyl acrylate, cyclohexyl methacrylate and lauryl methacrylate, N-dimethyl Monomers having a basic nitrogen such as aminopropyl (meth) acrylamide and dimethylaminoethyl (meth) acrylamide, monomers having an epoxy group such as glycidyl (meth) acrylate, hydroxyethyl (meth) acrylate, ( Monomers having hydroxyl groups such as hydroxypropyl (meth) acrylate, other styrene, methylstyrene, vinyltoluene, β-hydroxy (meth)
Phosphate ester of acrylate, and further (meth) acrylonitrile, (meth) acrylamide, vinyl acetate,
One or more monomers such as vinyl pyridine and the like, hydroxy compounds, amino compounds, epoxides and the like may be copolymerized. The above-mentioned acrylic copolymer is a conventional method in which a polymerization initiator is allowed to act in the presence of a polymerization solvent such as xylene, toluene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, isopropyl alcohol, butanol on a monomer mixture in a predetermined ratio. Can be produced by carrying out a copolymerization reaction.

The above-mentioned hydrolyzable silyl group-containing fluorine-containing copolymer exhibits excellent performance when used alone and in combination with a siloxane compound, but it is hydrolyzable in order to further improve stain resistance, hardness and the like. It is desirable to use it in combination with a silyl group-containing acrylic copolymer and a siloxane compound. When used in combination, the mixing ratio of both is 100 to 5 of the hydrolyzate of the fluorine-containing copolymer having a hydrolyzable silyl group in the solid content. %, Preferably 80 to 20% by weight, and 0 to 95% by weight, preferably 20 to 80% by weight, of a hydrolyzate of an acrylic copolymer having a hydrolyzable silyl group. When the content of the fluorine-containing copolymer is reduced in the case of being used in combination, the burnability and the weather resistance tend to be lowered. Further, when the content of the acrylic copolymer decreases, the hardness and stain resistance tend to decrease.

Further, the siloxane compound used in the present invention includes the following:

[0034]

[Chemical 2] (In the formula, R ¹ and R ² are the same or different and each is C
_A C ₁ -C ₄ alkyl group, R ³ and R ⁴ are the same or different and each is a C ₁ -C ₄ alkyl group, and n
May be different for each repeating unit, n is 2 to 1
It is an integer of 5)

[0035]

[Chemical 3] (In the formula, R ¹ and R ² are the same or different and each is H
Or a C ₁ -C ₇ alkyl group, and R ³ is C ₁ -C ₈
Which may be different for every n repeating units, n is an integer of 3 to 20, and m: n = 1:
1)

[0036]

[Chemical 4] (In the formula, R ¹ and R ² are the same or different and each is C
₁ is an alkyl group -C _4, n is an integer of 3 to 30).

In the present invention, a hydrolyzate of a fluorocopolymer having a hydrolyzable silyl group and a siloxane compound are mixed, or a hydrolyzate of a fluorocopolymer having a hydrolyzable silyl group is used. The reason for mixing the mixture with the hydrolyzate of the acrylic copolymer having a hydrolyzable silyl group and the siloxane compound is that the fluorocopolymer not hydrolyzed or the fluorocopolymer not hydrolyzed. When a mixture of the non-hydrolyzed acrylic copolymer and a siloxane compound are directly mixed, they are partially gelled or turbid, resulting in low value as a practical coating forming agent. Therefore, this is to prevent such a defect from occurring. Hydrolysis is the hydrolysis of a hydrolyzable silyl group. For example, taking an alkoxysilyl group as an example, a reaction represented by the following formula occurs:

[0038]

[Chemical 5] (In the formula, R is an alkyl group.) The hydrolyzate of the fluorine copolymer or the acrylic copolymer is preferably a partial hydrolyzate, and the partial hydrolysis means the fluorine-containing copolymer. It is preferable that the partial hydrolysis is in the range of 10 to 90%, and preferably 20 to 80% of the hydrolyzability of the hydrolyzable silyl group of the acrylic copolymer. If the hydrolysis rate is low, the compatibility of the siloxane compound becomes insufficient, and as the hydrolysis rate becomes higher, storage stability and the pot life after addition of the curing agent tend to become shorter.

If the fluorine-containing copolymer or the mixture of the fluorine-containing copolymer and the acrylic copolymer is hydrolyzed, the hydrolyzate and the siloxane compound can be uniformly mixed. Partial hydrolysis is more preferable because a partial cocondensate is produced and the curability and burnability of the coating film are further improved. Incidentally, the partial hydrolysis of the siloxane compound means 0 to 50 of the hydrolyzability of the siloxane compound.
%, Preferably in the range of 1 to 45%. As the hydrolysis rate increases, curability and flexibility are improved, but storage stability tends to deteriorate.

Regarding the hydrolysis method and the specific mixing method for obtaining the hydrolyzate used in the present invention, the solvent of the fluorine-containing copolymer and the acrylic copolymer is a solvent which can be uniformly mixed with water. It is preferably a composition. When the solvent composition is a composition that is immiscible or difficult to mix with water, it is necessary to dilute and adjust with a water-miscible solvent in advance so that the composition is miscible with water before adding water required for hydrolysis. .
If this operation is insufficient, the hydrolysis is not uniform, and particles or partial gelation tend to occur.

The siloxane compound is generally diluted with alcohol, and no special consideration is required before mixing with water, but in the case of a water-immiscible solvent diluted product, the same treatment as above is required. . Further, in the hydrolysis of the siloxane compound, a catalyst may be used for promoting the hydrolysis or promoting partial condensation or partial cocondensation of the hydrolyzate. Specific examples of such catalysts include inorganic acids such as nitric acid, hydrochloric acid and sulfuric acid, acetic acid, formic acid, propionic acid, maleic acid, chloroacetic acid, citric acid, benzoic acid, dimethylmalonic acid, glutaric acid and glycol. Acids, malonic acid, organic acids such as toluenesulfonic acid, organic bases such as aminos, amine salts, quaternary ammonium salts, guanidine compounds, and organic metals such as tin, aluminum, boron, titanium, silicon, zirconium, phosphorus Carboxylate, alkyl metal carboxylate, alkyl metal oxide, metal acid alkyl ester, metal alkoxide, etc.
Specifically, tin octylate, dibutyltin dilaurate, dibutyltin oxide, tetrabutyl titanate, triethyl borate, tetrabutylzirconium, acetylacetone aluminum, N-β (aminoethyl)
γ-aminopropyltrimethoxysilane, octylphosphoric acid titanium amino salt, and 1 to 4 of them can be used in appropriate combination. The amount of addition thereof is 0.01 to 7% by weight, preferably 0.5 to 5% by weight. If the amount added is too small, the curing speed will be slow, and if it is too large, storage stability and pot life will tend to be extremely poor.

The hydrolyzate of the fluorinated copolymer, or a mixture of the hydrolyzate of the fluorinated copolymer and the hydrolyzate of the acrylic copolymer, and the siloxane compound or a hydrolyzate thereof. The method for obtaining the mixture is as follows: individually hydrolyzing and then mixing, separately hydrolyzing and then mixing, and further hydrolyzing the mixture, hydrolyzate of fluorine-containing copolymer or fluorine-containing copolymer There is a method in which an unhydrolyzed siloxane compound is mixed with a mixture of the hydrolyzate of (1) and a hydrolyzate of an acrylic copolymer, or the whole is partially hydrolyzed, and it can be appropriately used.

The mixing ratio of the hydrolyzate of the fluorine-containing copolymer, or the mixture of the hydrolyzate of the fluorine-containing copolymer and the hydrolyzate of the acrylic copolymer, and the siloxane compound is solid content. 100: 10 to 230, preferably 100: 2
It is in the range of 5-150. If the content of the former is small, flexibility tends to decrease, and if the content is large, hardness and stain resistance tend to decrease.

The inorganic / organic composite coating binder thus obtained is dissolved in a solvent or dispersed in a solvent before use to prepare a coating solution of 60-
Heat cure at 200 ℃, or use a curing agent,
Heat and cure at room temperature to 180 ° C. As the curing agent, the above-mentioned hydrolysis promoting catalyst can be appropriately used. The addition amount is 0.1 to 5 parts by weight, preferably 0.2 to 3 parts by weight, based on 100 parts by weight of the binder solid content. When the amount of the curing agent added is small, the curing speed at room temperature is slow, and when the amount is too large, the pot life tends to be extremely short. The inorganic / organic composite coating agent is obtained by dissolving or dispersing the binder in a solvent, and is used by appropriately mixing it with the above-mentioned catalyst, pigment, additive, various modifiers, water scavenger, etc., if necessary. can do.

As the solvent, aromatic compounds such as toluene and xylene, methanol, ethanol, isopropanol,
Examples thereof include alcohol solvents such as butanol, glycol monoethyl ether and glycol monobutyl ether, ester solvents such as ethyl acetate, butyl acetate and cellosolve acetate, and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. These solvents are 80 to 50 relative to 100 parts by weight of the solid content of the binder.
It can be used in the range of 0 parts by weight.

Examples of the pigment include various inorganic pigments such as titanium oxide, carbon black, iron oxide, and lead oxides (nickel titanium type, chromium titanium type, bismuth vanadium type), quinacridone, diketopyrrolopyrrole, and benzimidazo. Representative examples thereof include various organic pigments such as ron, isoindolinone, anthrapyrimidine, phthalocyanine, threne, and dioxazine. Further, various extender pigments such as talc, mica, calcium carbonate, barium sulfate, silicon oxide, aluminum oxide, kaolin, etc., plastic beads, and sensate pigments can be used. These pigments can be used in the range of 10 to 400 parts by weight based on 100 parts by weight of the solid content of the binder.

Examples of the additives and various modifiers include various pigment dispersants, precipitation inhibitors, surface modifiers, ultraviolet absorbers, etc. These are 0.1 parts by weight with respect to 100 parts by weight of the solid content of the binder. It can be used in the range of 10 to 10 parts by weight.

As the moisture scavenger, an ester-based dehydrating agent having a high hydrolysis rate is preferable because it prevents deterioration of storage stability caused by mixing of water into the binder during the mixing and kneading steps of the pigment. Specifically, trimethyl orthoformate, triethyl orthoformate, trialkyl orthoformates such as tripropyl orthoformate, trimethyl orthoacetate, triethyl orthoacetate, trialkyl orthoacetates such as tripropyl orthoacetate, tetramethyl orthosilicate, Tetraalkyl orthosilicate such as tetraethyl orthosilicate and tetrapropyl orthosilicate are appropriately used.
The amount used can be in the range of 0.1 to 3 parts by weight with respect to 100 parts by weight of the binder solid content.

Production examples of raw materials used in the present invention, examples of the present invention, comparative examples and measurement tests will be described below.
The present invention is not limited to these.

Production Example 1 800 g of benzene, butyl vinyl ether (BV) were placed in a stainless steel autoclave with a stirrer having a capacity of 3000 cc.
E) 252 g, trimethoxyvinylsilane (TMVS)
71 g and 10 g of dilauroyl peroxide were charged, solidification with acetone and dry ice and deaeration were performed to remove oxygen in the system. After that, hexafluoropropene (HF
450 g of P) was introduced into the autoclave and the temperature was raised. The pressure at the time when the temperature inside the autoclave reached 65 ° C. was 8.1 Kg / cm ² . The reaction was continued for 8 hours with stirring, and when the pressure reached 4.6 Kg / cm ² , the autoclave was water-cooled to stop the reaction. After cooling, the unreacted monomer was expelled, the autoclave was opened, and the reaction solution was taken out. After concentration, the mixture was washed with a benzene / methanol mixed solvent, concentrated and dried again. Polymer yield is 6
It was 00 g.

The number average molecular weight of the obtained polymer by GPC was 1.0 × 10 ⁴ , and the glass transition point was −14 ° C.
Met. In addition, the composition analysis of this copolymer is carried out by elemental analysis and N
When using MR, HFP / BVE / TMVS =
It was 48/40/12 (molar ratio). This copolymer 5
00 g was dissolved in a mixture of 50 g of isopropanol and 450 g of toluene to obtain a fluorocopolymer varnish having a hydrolyzable silyl group.

Production Example 2 As the fluorine-containing copolymer varnish having a hydrolyzable silyl group, commercially available "Zeffle VE420S-1" (manufactured by Daikin Industries, Ltd.) was used. The physical properties were as follows: Varnish viscosity 290 cp (B type 25 ° C) Solid content concentration 60.9% Triethoxysilyl group content 11.5% Solvent composition Butyl acetate 94% Toluene 6% Production Example 3 Fluorine-containing copolymer As the polymer varnish, a commercially available “Zeffle GK550” (manufactured by Daikin Industries, Ltd.) having the following physical properties was used: Varnish viscosity 1700 cp (B type 25 ° C.) Solid content concentration 59.6% Solid content OH value 95 Solvent composition Xylene 70% Butyl acetate 30% In a beaker with a capacity of 1000 cc, place the above "Zeffle GK
550 "380 g was charged, and at room temperature (15 to 25 ° C),
While stirring at 800 rpm with a stirrer, 83 g of γ-isocyanatopropylmethyldimethoxysilane and 1 g of a 1% xylene solution of dibutyltin dilaurate were added, and 5
By reacting for a time, a hydrolyzable silyl group-containing fluorine-containing copolymer was produced.

Production Example 4 667 g of xylene and 75 g of isopropanol were charged into a three-necked flask with a stirrer made of glass and having a capacity of 3000 cc, and the temperature was raised to 95 ° C. While maintaining this temperature, a mixture of 248 g of methyl methacrylate, 330 g of isobutyl methacrylate, 172 g of γ-methacryloxypropyltrimethoxysilane and 2.3 g of t-butylperoxy 2-ethylhexanoate was added dropwise over 3 hours. . Then, what melt | dissolved 1.5 g of t-butyl peroxy 2-ethylhexanoate in 7.5 g of xylene was dripped over 2 hours. After that, the reaction was continued under stirring for 2 hours and cooled to complete the reaction. The heating residue of the obtained polymer was 50.6%, and the number average molecular weight by GPC was 1.1 × 10 ⁴ .

Example 1 In a beaker having a capacity of 1000 cc, 450 g of the varnish obtained in Production Example 1 was placed, and isopropyl alcohol 260 was added thereto.
g, and after mixing uniformly, 600-800 with a stirrer
While stirring at rpm, 9.2 g of water was added, and the mixture was stirred at room temperature (15-
The stirring was continued at 25 ° C. for 3 hours (hydrolysis rate 82%).
A siloxane compound (methyl silicate MS51 manufactured by Mitsubishi Kasei Co., Ltd.) 26 was added to the hydrolyzate while stirring.
0 g was mixed, 19.3 g of water, 2.6 g of acetylacetone aluminum and 2.6 g of triethylboric acid were added, and stirring was continued for 2 hours (hydrolysis rate: 40% methyl silicate equivalent) to obtain the desired product.

Example 2 In a beaker having a capacity of 1000 cc, 384 g of the varnish obtained in Production Example 2 was placed, and isopropyl alcohol 336 was added thereto.
g, and after mixing uniformly, 600-800 with a stirrer
Water (11.6 g) was added with stirring at room temperature (15
The stirring was continued at -25 ° C for 3 hours (hydrolysis rate 50
%). A siloxane compound (ethyl silicate 40 manufactured by Colcoat Co., Ltd.) was added to the hydrolyzate while stirring.
338 g were mixed, 4.9 g of water, 3.4 g of acetylacetone aluminum and 3.3 g of tributyl boric acid were added, and stirring was continued for 2 hours (hydrolysis rate: 10% ethyl silicate 40 equivalent) to obtain the desired product. It was

Example 3 In a beaker having a capacity of 1000 cc, 460 g of the varnish obtained in Production Example 3 was placed, and isopropyl alcohol 260 was added thereto.
g, and after mixing uniformly, 600-800 with a stirrer
Water (11.0 g) was added while stirring at room temperature, and room temperature (15
The stirring was continued at -25 ° C for 3 hours (hydrolysis rate 70
%). A siloxane compound (ethyl silicate 40 manufactured by Colcoat Co., Ltd.) was added to the hydrolyzate while stirring.
338 g was mixed, and further 14.2 g of water, 1.7 g of acetylacetone aluminum and 1.6 g of triethyl boric acid.
Was added and stirring was continued for 2 hours (hydrolysis rate: 30% ethyl silicate equivalent) to obtain the desired product.

Example 4 In a beaker having a capacity of 1000 cc, 460 g of the varnish obtained in Production Example 3 was placed, and isopropyl alcohol 260 was added thereto.
g, and after mixing uniformly, 600-800 with a stirrer
Water (11.0 g) was added while stirring at room temperature, and room temperature (15
The stirring was continued at -25 ° C for 3 hours (hydrolysis rate 70
%). A siloxane compound (Aquaseal 200S manufactured by Sumitomo Seika Chemicals, Ltd.) 4 was added to the hydrolyzate while stirring.
50 g were mixed, 1.7 g of acetylacetone aluminum and 1.6 g of triethyl boric acid were further added, and stirring was continued for 2 hours to obtain the target product.

Example 5 In a beaker having a capacity of 1000 cc, 460 g of the varnish obtained in Production Example 3 was placed, and isopropyl alcohol 260 was added thereto.
g, and after mixing uniformly, 600-800 with a stirrer
Water (11.0 g) was added while stirring at room temperature, and room temperature (15
The stirring was continued at -25 ° C for 3 hours (hydrolysis rate 70
%). A siloxane compound (Silicon AFP-2 manufactured by Shin-Etsu Chemical Co., Ltd.) was added to the hydrolyzate while stirring.
100 g was mixed, 1.7 g of acetylacetone aluminum and 1.6 g of triethyl boric acid were further added, and stirring was continued for 2 hours to obtain the target product.

Example 6 In a beaker having a capacity of 1000 cc, 460 g of the varnish obtained in Production Example 3 was placed, and isopropyl alcohol 260 was added thereto.
g, and after mixing uniformly, 600-800 with a stirrer
Water (11.0 g) was added while stirring at room temperature, and room temperature (15
The stirring was continued at -25 ° C for 3 hours (hydrolysis rate 70
%). A siloxane compound (Shin-Etsu Chemical Co., Ltd., silicon AFP-6) was added to the hydrolyzate while stirring.
C) 70 g are mixed, 1.7 g of acetylacetone aluminum and 1.6 g of triethylboric acid are added, and 2)
The stirring was continued for an hour to obtain the desired product.

Example 7 A beaker having a capacity of 1000 cc was charged with a mixture of 167 g of the "Zeffle VE420S-1" varnish described in Production Example 2 and 250 g of the varnish obtained in Production Example 4, to which 293 g of isopropyl alcohol was added. After uniformly mixing, 9.4 g of water was added while stirring at 600 to 800 rpm with a stirrer, and stirring was continued for 3 hours at room temperature (15 to 25 ° C.) (hydrolysis rate 61%). To this hydrolyzate, 338 g of a siloxane compound (Ethyl silicate 40 manufactured by Colcoat Co., Ltd.) was mixed while continuing stirring, and 4.9 g of water, 1.7 g of acetylacetone aluminum and 1.6 g of triethylboric acid were added, and the mixture was added for 2 hours. The stirring was continued (hydrolysis rate: corresponding to 10% ethyl silicate) to obtain the desired product.

Example 8 A mixture of 100 g of the varnish obtained in Production Example 3 and 350 g of the varnish obtained in Production Example 4 was placed in a beaker having a capacity of 1000 cc, and 260 g of isopropyl alcohol was added thereto.
After homogeneously mixing, add 8.5 g of water while stirring at 600 to 800 rpm with a stirrer, and then at room temperature (15 to 25 ° C.)
The stirring was continued for 3 hours (hydrolysis rate 70%). To this hydrolyzate, 338 g of a siloxane compound (Ethylene Silicate 40 manufactured by Colcoat Co., Ltd.) was mixed with continuing stirring, and 14.2 g of water, 1.7 g of acetylacetone aluminum and 1.6 g of triethylboric acid were added, and 2
Stirring was continued (hydrolysis rate: 30% ethyl silicate equivalent) to obtain the desired product.

Comparative Example 1 A monomer mixture consisting of 47% tetrafluoroethylene, 30% cyclohexyl vinyl ether, 8% ethyl vinyl ether and 15% hydroxybutyl vinyl ether was copolymerized according to the method described in JP-A-57-34107. And a fluorine-containing copolymer (hydroxyl value 43.4%,
A xylol solution (solid content 60%) of Tg 35 ° C.) was obtained.

Measurement test Preparation of test plate A gypsum slag perlite plate (thickness: 12 mm) was used as a material, and a polyisocyanate prepolymer solution sealer "V Seran # 100 sealer" (trade name, manufactured by Dainippon Paint Co., Ltd.) on its surface ( Butyl acetate: xylene = 100% diluted with a solvent of 1: 1) applied amount is 90 to 100 g / m ^2.
Spray coating was performed so that the (wet weight) was obtained. This is 10
It was dried at 0 ° C. for 5 minutes. Acrylic silicone resin-based paint "V Seran # 50" is applied as a base coating on this dried surface.
0 enamel ”(trade name of Dainippon Paint Co., Ltd.) (40% diluted with a solvent of butyl acetate: xylene = 1: 1) is sprayed so that the applied amount is 80 to 90 g / m ² (wet weight). Painted. This was dried at 120 ° C. for 15 minutes. Coatings 1 to 9 having the compositions shown in Table 1 were spray-coated as a top coat coating on the dried surface so that the coating amount was 70 to 80 g / m ² (wet weight). 15 at 120 ℃
After drying for 1 minute, the film was stored at room temperature for 3 days, and the characteristics of the film were measured by the following methods.

Test method Hardness: Pencil hardness measured according to JIS-K-5400, Hot water resistance: The test piece was immersed in tap water at 60 ° C. for 7 days to visually determine the abnormality of the coating film: ○ None, △: slight changes such as decrease in gloss, whitening, etc. ×: large changes in decrease in gloss, whitening, etc. Contamination resistance: Decontamination resistance of red and black magic ink after 24 hours: ◎ ・ ・ ・ Complete Removal, ○ ・ ・ ・ Extremely slight pollution, △ ・ ・ ・ Contamination, × ・ ・ ・ Significant contamination, Weather resistance: Sunshine Weather-O-meter 3000
Time: ○: No change in coating appearance, gloss retention 95%, △: slight change in coating, gloss retention 95%, ×: marked change in coating, gloss retention 80% Frost resistance: Measured by the ASTM-C666A method: ○: No cracks, △: Minor cracks or partial peeling of the coating, ×: Marked cracks, paint peeling.

[0065]

[Table 1]

[0066]

[Table 2]

Claims (5)

[Claims] 1. A binder for an inorganic / organic composite coating agent, which comprises a hydrolyzate of a fluorocopolymer having a hydrolyzable silyl group and a siloxane compound. 2. An inorganic material comprising a hydrolyzate of a fluorine-containing copolymer having a hydrolyzable silyl group, a hydrolyzate of an acrylic copolymer having a hydrolyzable silyl group, and a siloxane compound. Binder for organic composite coating agent. 3. A hydrolyzate of a fluorocopolymer having a hydrolyzable silyl group in an amount of 100 to 5% by weight and a hydrolyzate of an acrylic copolymer having a hydrolyzable silyl group in an amount of 0 to 95% by weight. A binder for an inorganic / organic composite coating material, which is a mixture obtained by mixing 100 parts by weight of the mixture and 10 to 230 parts by weight of the siloxane compound. 4. The binder for an inorganic / organic composite coating agent according to claim 1, 2 or 3, wherein the hydrolyzate is obtained by hydrolyzing 10 to 90% of the hydrolyzability of the hydrolyzable silyl group. 5. The binder for an inorganic-organic composite coating agent according to claim 1, 2, 3 or 4, wherein the siloxane compound is obtained by hydrolyzing 0 to 50% of the hydrolyzability of the siloxane compound.