JPH04136022A - Curable composition and article coated therewith - Google Patents

Abstract

PURPOSE:To prepare a curable compsn. esp. useful for coating in applications where durability is required by compounding an epoxy compd. having at least two epoxy groups in the molecule, a siloxane compd. having two silanol groups in the molecule, and an organozirconium compd. CONSTITUTION:A curable compsn. useful as a clear topcoating material, adhesive, sealant, plastics modifier, etc., is prepd. by compounding an epoxy compd. having at least two epoxy groups in the molecule (e.g. an epoxidized acrylic resin having an epoxy equivalent of 200-10000), a siloxane compd. having two silanol groups in the molecule, and an organozirconium compd. (e.g. Zr alkoxide) in a wt. ratio of the epoxy compd. to the siloxane compd. of 9/1-1/9, pref. 8/2-2/8, and in an amt. of the zirconium compd. of 0.01-50 pts.wt., pref. 0.1-20 pts.wt. based on 100 pts.wt. in total of the epoxy compd. and the siloxane compd.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to various coatings such as building exteriors, automobiles, industrial machinery, steel furniture, home appliances, and plastics, especially applications requiring durability. The present invention relates to a composition used for coating.

[Prior art/invention or problem to be solved] Conventional thermosetting paints such as alkyd melamine and acrylic melamine are one-component and have excellent workability, but they have problems with odor generated from the melamine resin during baking and acid resistance. The drawback is that it has poor durability and weather resistance.

On the other hand, acrylic urethane paints exhibit excellent coating film properties, but are two-component and have poor workability. In addition, the toxicity of isocyanate is becoming a social issue, and the development of a new resin composition that is a one-liquid product that contains isocyanate and has excellent physical properties such as weather resistance and weather resistance is being sought.

[Means to solve the problem]

The inventors of the present invention have made intensive studies to solve the above problems, and have found that a composition consisting of an epoxy group-containing compound, a silanol group-containing compound, and an organic zirconium compound is stable as a single liquid at room temperature, and can be formed easily. It was discovered that the resulting coating film is excellent in weather resistance, appearance, and chemical resistance, leading to the present invention.

That is, the present invention provides a cured product consisting of (^) a compound having two or more epoxy groups in one molecule, (B) a white silanol compound having two or more silanol groups in one molecule, and (C) an organic ruconium compound. A painted object, which is coated with a paint containing a coloring composition, a metallic powder, and/or a colored pigment, and a topcoat clear paint is coated on the painted surface, and the top coat clear paint contains the composition. The present invention relates to a coated article characterized by having a curable paint as a main component.

〔Example〕

The component (^) used in the present invention, a compound having two or more epoxy groups in one molecule (hereinafter also referred to as an epoxy group-containing compound), has hardness immediately after baking, solvent resistance, chemical resistance,
It is a component used to improve the physical properties of a coating film such as adhesion, and preferably contains three or more epoxy groups. If the number of epoxy groups is less than two, crosslinking will be insufficient, and necessary coating properties such as hardness, chemical resistance, and solvent resistance cannot be improved.

Specific examples of epoxy group-containing compounds include ethylene glycol chlorine ether, neopentyl glycol cyclocidyl ether, 6-hexaneol cyclocidyl ether, bisphenol A diclycidyl ether, and chrylycerin triclicidyl. Polycricidyl ethers of polyhydric alcohols (polyols); sifulidyl esters of phthalic acid, sifulidyl esters of isophthalic acid, sifulidyl esters of adipic acid; polyhydric carboxylic acids (polycarphonic acids)
Polycrindyl esters; dicrycidyl ether type epoxy resins from bisphenol A or bisphenol F, nophorac type epoxy resins, hydantoin ring-containing epoxy resins, dicrycidyl ethers and epoxy resins of polyglycols such as polyethylene glycol and polypropylene glycol. Epoquine compounds with various epoxy resins such as urethane-modified Epoquine urethane resins, as well as cricidyl ester ether of p-oxybenzoic acid or various vinyl (co)polymers having an epoxy group in the side chain, Epoxy-modified silicone oils, partial hydrolysates of epoxy group-containing alkoxysilanes such as γ-crisitoxypropyltrimethoxysilane or β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and epoxy group-containing acrylic resins. can give. In particular, since epoxy group-containing acrylic resin is a main chain or acrylic resin, it has excellent durability, solvent resistance,
Excellent chemical resistance.

Epoxy group-containing acrylic resins can be easily scaled by copolymerizing epoxy group-containing vinyl nitrates with acrylic acid or methacrylic acid derivatives.

Furthermore, a wide variety of resin designs are possible by changing the monomer composition, amount of initiator, and type and amount of functional groups used.

There are no particular limitations on the epoxy group-containing vinyl monomer, but
Examples include kurindyl (meth)acrylate, β-methylcricidyl (meth)acrylate, allylchrysinyl ether, shifrincil malate, β~methylcricidyl malate, shifrindyl fumarate, di-β-methyl-
Glycisyl fumarate, a (meth)acrylic acid ester having an alicyclic epoxy group, A manufactured by Daicel Chemical Industry Co., Ltd.
Examples include ETHB and METHB.

These epoxy group-containing vinyl monomers may be used alone or in combination of two or more.

There are no particular limitations on the derivatives of acrylic acid or methacrylic acid that can be copolymerized with the epoxy group-containing vinyl monomer, and specific examples include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2- ethylhexyl (meth)acrylate,
Stearyl (meth)acrylate, Hensyl (meth)acrylate, Cyclohexyl (meth)acrylate, Trifluoroethyl (meth)acrylate, Pentafluoropropyl (meth)acrylate, Perfluorocyclohexyl (meth)acrylate, (meth)acrylonitrile, (meth)acrylate ) Acrylamide, a-ethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide, N, λ-7 methylacrylamide, N-methylacrylamide, macromer AS-6 manufactured by Toagosei Chemical Industry ■, AX ( -6, A^-6, AB-6, AX-5
, a phosphate group-containing vinyl compound which is a condensation product of hydroquine alkyl esters of α,β-ethylenically unsaturated carbonic acid and phosphoric esters, such as hydroxyalkyl esters of (meth)acrylic acid, (Meth)acrylate containing urethane bonds and siloxane bonds, γ
- (meth)acryloxypropyltrimethoxysilane,
Alkoxysilyl group-containing (meth)acrylates such as γ-(meth)acryloxypropylmethyldimethoxysilane, γ-(meth)acryloxypropyl-dimethylmethoxyrane, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth) ) acrylate, 2-
Hydroxyethyl vinyl ether, N-methylol(meth)acrylamide, Aronix 5700.4-hydroxystyrene manufactured by Toagosei Chemical Co., Ltd., HE-10, HE-20, IP-10 and ) I manufactured by Nippon Shokubai Chemical Co., Ltd.
P-20 (all acrylic acid ester oligomers having a hydroxyl group at the end), Blenmar PP Release (polypropylene glycol methacrylate) manufactured by NOF■,
Blenmar PE Release (polyethylene glycol monomethacrylate), Blenmar PEP series (polyethylene glycol polypropylene glycol methacrylate), Blenmar AP-400 (polypropylene glycol monoacrylate), Blenmar AE-350 (polyethylene glycol monoacrylate), Blenmar NKH-5050 (polypropylene glycol) polytrimethylene monoacrylate) and Blenmar GLM
(glycerol monomethacrylate), ε-prolactone-modified hydroquine alkyl vinyl monomer obtained by the reaction of a hydroxyl group-containing vinyl compound and ε-caprolactone.

Typical examples of the ε-caprolactone-modified hydroquine alkyl vinyl monomer include Daicel Chemical, which has a structure represented by the formula: (wherein, R is 1] or CI+3, and k is an integer of 1 or more). Placel F^-1 (R'-II, k-1) manufactured by Kogyo ■,
Placel F^-4 (R'-IL k-4),
Placel PH-1 (R'-CI, k-1
) and Placel PH-4 (R'-Cl13
, Ni-4), TONE M-100 (R1
-Hlk-2) and TONCM201 (R1-CI
+3, k-1), etc. Curability is improved by copolymerizing these hydroxyl group-containing monomers.

The copolymer may contain segments formed by urethane bonds or siloxane bonds in the main chain, within a range not exceeding 50% (by weight, the same hereinafter), and (meth)
It may also contain segments derived from monomers other than acrylic acid derivatives. The monomer is not limited, and specific examples include aromatic hydrocarbon-based vinyl compounds such as styrene, α-methylstyrene, chlorostyrene, and vinyltoluene; maleic acid, fumaric acid, and itaconic acid. Salts of unsaturated carboxylic acids (alkali metal salts, ammonium salts, amine salts, etc.) or diesters of them with linear or branched alcohols having 1 to 20 carbon atoms; vinyl acetate, vinyl propionate, diallyl phthalate, etc. vinyl esters and allyl compounds, itaconic acid diamide, crotonamide, maleic acid diamide, fumaric acid diamide, amide group-containing vinyl compounds such as N-vinylpyrrolidone; methyl vinyl ether, ncrohexyl vinyl ether, vinyl chloride, vinylidene chloride, Chloroprene, 1-propylene, butanene, isoprene,
Examples include fluoroolefin maleimide, vinyl imidazole, and other vinyl compounds.

The epoxy group-containing acrylic resin is preferably produced by a solution polymerization method using an azo radical initiator such as azobisisobutyronitrile for ease of synthesis.

In solution polymerization, the molecular weight can be adjusted by using a chain transfer agent such as n-dodecylmercaptan, t-dodecylmercaptan, or n-butylmercaptan, if necessary.

Further, the polymerization solvent is not particularly limited as long as it is a non-reactive solvent.

There is no particular limitation on the molecular weight of the epoxy group-containing acrylic resin, and any commonly used acrylic resin may be used. In terms of physical properties, the number average molecular weight is 1,500.
~40,000, preferably 3,000~25
.
From the viewpoint of coating film properties such as durability, the epoxy group-containing acrylic resin has an epoxy equivalent of 100 to 20,000, more preferably 200 to 10,000.

One type of such epoxy group-containing acrylic resin may be used, or two or more types may be used in combination.

The siloxane compound having two or more silanol groups in one molecule, which is component (B), has two or more, preferably three or more, silanol groups and is compatible with component A. Can be used without limitation. If there are less than two silanol groups in one molecule, crosslinking will be insufficient and necessary coating properties such as hardness, chemical resistance, and solvent resistance cannot be improved. The siloxane bond is very stable, and by using the siloxane compound, a cured product with excellent durability, chemical resistance, solvent resistance, and flexibility can be obtained.

The structure of the siloxane compound may be any linear, branched, network, or cyclic structure, and the organo group may include a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a methyl group, an ethyl group, a propyl group, Examples include butyl group, hekynyl group, allyl group, and phenyl group. Among these compounds having an ork group, those having a methyl group or a phenyl group, which are produced in a main beam manner and are inexpensive, are practically advantageous.

Further, the siloxane compound may contain a reactive functional group other than a silanol group, such as an alkoxylyl group, an alcoholic hydroxyl group, a chrycidyl group, an amino group, a mercapto group, a carboxyl group, an amide group, a vinyl group, Examples include meth)acryloxy groups.

The molecular weight of the siloxane compound is not particularly limited as long as it is compatible, but as the molecular weight increases, the compatibility decreases, so it is preferable that the siloxane compound has 2 to 300 silicon atoms, and 2 to 100 silicon atoms. It is more preferable to have 3 to 50 pieces, and particularly preferably 3 to 50 pieces.

Specific examples of such siloxane compounds include silicone rubber, silicone varnish, Shin-Etsu Chemical Co., Ltd.
Made by Kl? 211 KI? 2+2, KR214, KI
? 21 [i, l--SII [101 made by Renricorn ■
Silicone intermediate for modifying organic polymers, reactive polydimethylsiloxane used as reactive silicone oil, reactive polydimethylsiloxane, reactive polymethylphenylsiloxane of dimethyl and diphenyl copolymerization type, (R2 is phenyl group, carbon number 1-4
(a group selected from the group consisting of an alkyl group and a hydroxyl group)
, [blank below] (R3 is a group selected from the group consisting of a phenyl group, an alkyl group having 1 to 4 carbon atoms, and a hydroxyl group, and has at least two 5i-01i, 475m, and n are each 1 to 5),
Examples include hydrolyzed condensates of hydrolyzable silane compounds.

Specific examples of the hydrolyzable silane compounds include ethyl silicate, methyltrimethoxine silane, ethyltrimethoxysilane, butyltrimethoxysilane, octyltrimethoxine silane, dodecyltrimethoxine silane, phenyltrimethoxine silane, and vinyltrimethoxine silane. , γ-methacryloxypropyltrimethoxine silane, γ-acryloxypropyltrimethoxine silane, γ
- Chrysitoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, diethyljethoxysilane, diethyldimethoxysilane, dibu- Tyldimethoxysilane, diphenylremethoxysilane, vinylmethyldimethoxysilane, γmethacryloxypropylmethyldimethoxysilane, trimethylmethoxysilane, triethylmethoxysilane, triphenylmethoxysilane,
Ethyl silicate, methyltriethoxysilane, ethyltriethoxysilane, butyltriethoxysilane, octyltriethoxysilane, F-decyltriethoxysilane, phenyltriethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acrylic Roxypropyltriethoxysilane, γ-crisitoxypropyltriethoxysilane, γ-mercaptopropyltriethoxysilane, γ-aminopropyltriethoxysilane, N-βaminoethyl-γ-aminopropyltriethoxysilane, dimethyljethoxysilane,
Diethyljethoxysilane, dibutylthiethoxysilane, diphenyljethoxysilane, vinylmethyljethoxysilane, γ-methacryloquinepropylmethyldiethoxysilane, trimethylethoxysilane, triethylethoxysilane, triphenylmethoxysilane, manufactured by Nippon Colcourt Chemical Co., Ltd. methyl silicate 47, methyl silicate 511 methyl silicate 55, methyl silicate 58,
Methyl silicate 60, ethyl silicate 40, RAS
-1, HAS-6, RAS-10, Shin-Etsu Chemical ■
8 FP-1, ^FR-2, AFP-8, KR
213, KR217, KR9218, TSRIB5, TR3357 manufactured by Toshiba Silicone ■.

Y-1587, FZ-3701 manufactured by Nippon Unicar ■,
Examples include PZ3704.

As a method for hydrolytic condensation, for example, one or more of the above-mentioned hydrolyzable Nran compounds are combined, 11□0 necessary for hydrolyzing the alkoxysilyl group of St. Accordingly, it can be easily obtained by adding a small amount of a condensation catalyst such as hydrochloric acid or sulfuric acid, raising the temperature to 1A to 100°C, and not proceeding with the condensation until the alcohol produced is removed.

There is no particular limitation on the usage ratio of the siloxane compound (B) having two or more silanol groups in one molecule, but the weight ratio of component (A)/component (B) is 9/1 to 1/9. Preferably, 8/2 to 2/8, more preferably 8/2 to 2/8. If the usage ratio exceeds 9/1 or is less than 1/9, the characteristics of each component tend to be insufficient.

The organic zirconium compound which is component (C) used in the present invention is a component for promoting the reaction between an epoxy group and a silanol group, and is not particularly limited as long as it can be used for this purpose. From the viewpoint of curing activity, zirconium compounds containing at least one alkoxy group are desirable.

Examples of organic zirconium compounds include tetraethylzirconate, tetra-rhopropylzirconate, tetraisopropylzirconate, tetra-n-butylzirconate, tetra-5QC-butylzirconate, tetra-
tert-butylzirconate, tetra-n-pentylzirconate, tetra-tert-pentylzirconate, tetra-tert-hexylzirconate, tetra-n-hebutylzirconate, tetra-n-octylzirconate, tetra- There are also zirconates such as n-stearyl zirconate, especially tetraisopropyl zirconate, tetra-n-propyl zirconate, tetra-isobutyl zirconate, tetra-n-butyl zirconate, tetra-5ecbutyl zirconate, tetra-
Examples include tert-butyl zirconate, and when these are used, compositions with suitable performance can be obtained. Also, tetraisopropyl zirconate,
Dimeric or higher compounds such as tetra-n-propyl zirconate, tetra-n-butyl zirconate, tetraisobutyl zirconate, tetra-5ee-butyl zirconate, and tetra-tart-butyl zirconate can also be used. Moreover, these zirconates may also contain a structural unit in which they are associated with each other. Furthermore, chelate compounds such as tetrakis (n-propylacetoacetate) zirconium, tetrakis (acetylacetonate) zirconium, tetrakis (ethylacetoacetate) zirconium, 1so-butoxytris (acetylacetonate)
Zirconium, di-1so-butoxy-bis(acetylacetonato)zirconium, tri-1so-butoxyacetylacetonatozirconium, n-butoxytris(acetylacetonato)zirconium, di-butoxybis(acetylacetonato)zirconium, trilobtoxyacetylacetonate Nato zirconium, 1
so-propoxytris(acetylacetonato)zirconium, di-1so-propoxybis(acetylacetonato)zirconium, tri-1so-propoxyacetylacetonatozirconium, n-butoxytris(ethyl-acetoacetate)zirconium, sea n-
Examples include butoxybis(ethylacetoacetate)zirconium, tri-n-butoxy(ethylacetoacetate)zirconium, monoethylacetoacetatetris(acetylacetonate)zirconium, and the like.

The blending amount of the organic zirconium compound (C) is 0.01 to 50 parts, more preferably 1 to 20 parts, per 100 parts of solid content of components (A) and (B), 1 part (the same applies hereinafter). Is it preferable?

If the amount is less than 0.01 part, crosslinking will be insufficient and necessary physical properties such as solvent resistance and chemical resistance cannot be changed.
The coating film tends to become brittle if it exceeds this point.

A dehydrating agent may or may not be used in the composition of the present invention, but by using a dehydrating agent, long-term stability and stability that can be used repeatedly can be ensured.

Specific examples of dehydrating agents include methyl orthoformate,
Examples include hydrolyzable ester compounds such as methyl orthoformate, methyl orthoacetate, ethyl orthoacetate, methyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, methyl alcohol, and ethyl silicate.

There is no particular limitation on the amount of the dehydrating agent used, but it is usually 100 parts or less, preferably 50 parts or less, based on 100 parts of the solid content of component (^) and (B).

A solvent may be used in the composition of the present invention, and the solvent used may be a non-reactive solvent.

Specific examples of such solvents include aliphatic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, alcohols, ketones, esters, etc., which are used in general paints, coatings, etc. Examples include ethers, alcohol esters, ketone alcohols, ether alcohols, ketone ethers, ketone esters, and ester ethers. Among these, it is preferable to use a solvent containing an alkyl alcohol because it improves the stability of the composition of the present invention.

The alkyl alcohol is preferably an alcohol whose alkyl group has 1 to IO carbon atoms, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, 5eC-butyl alcohol, te
rt-butyl alcohol, n-amyl alcohol, isoamyl alcohol, hexyl alcohol, octyl alcohol, cellosolve, etc. are used. There is no particular limitation on the amount of alcohol used, but it is usually at most 100 parts, preferably at most 50 parts, based on 100 parts of the solid content of component (^) and component (B).

The stability of the composition can also be improved by using acetylacetone, ethyl acetoacetate, or the like, which are zirconium chelate ligands, as a solvent.

The combined use of alcohol, especially alkyl alcohol, with a dehydrating agent, and acetylacetone or ethyl acetoacetate will affect the storage stability when components (A), (B), and (C) of the composition of the present invention are mixed and stored. A noticeable effect can be seen.

The amount of solvent used varies depending on the molecular weight or composition of component (A) and component (B), and is adjusted according to the practically required solid content concentration or viscosity.

A hydrolyzable silane compound, a condensate thereof having less than two silanol groups, a reactant thereof, or a mixture thereof may be added to the composition of the present invention in order to improve performance such as adhesion, hardness, and solvent resistance. You may.

As the hydrolyzable silane compound, the compounds mentioned above as raw materials for siloxane compounds having two or more silanol groups can be used.

Depending on the purpose, the composition of the present invention may contain additives such as diluents, pigments (including extender pigments), ultraviolet absorbers, anti-settling agents, and leveling agents; and fibers such as nitrocellulose and cellulose acetate butyrate. Base; melamine resin, vinyl chloride resin, chlorinated polyolefin, chlorinated rubber, polyvinyl butyral, alkyd resin, oil-free alkyd resin, acrylic modified alkyd resin, acrylic resin, fluororesin containing hydroxyl group, polyester polyol, polyether polyol, polyurethane polyol, etc. A resin may be added.

There are no particular limitations on the method for preparing the curable composition of the present invention, and it can be prepared in a conventional manner.

The curable composition of the present invention can be used in paints, adhesives, sealants,
It is useful as a modifier for plastics, etc., and especially when used as a paint, it produces a coating film with excellent weather resistance, adhesion, hardness, etc., and excellent durability.

The composition of the invention can be applied, for example, by dipping, spraying, brushing,
After being applied to the object to be coated by a conventional method such as a method using a roll coater or a flow coater, it can be cured at a temperature of 30°C or higher, preferably 55 to 350°C.

Next, the coated article of the present invention will be explained.

The painted object of the present invention is coated with a paint containing metallic powder and/or a colored pigment (a paint containing a metallic powder is also referred to as a metallic coat, a paint containing a colored pigment is also referred to as a solid color coat), Since the painted surface is coated with a top coat clear curable paint, such as a thermosetting paint, containing the above-mentioned curable composition as a main component, the coated product has excellent weather resistance, acid resistance, stain resistance, etc. It is.

The paint containing the metallic powder and/or colored pigment is not particularly limited, but includes, for example, amino alkyd resin, oil-free alkyd resin, thermosetting acrylic resin, thermosetting urethane resin, nitrocotton lacquer, modified acrylic lacquer, and straight acrylic lacquer. , room-temperature-curing urethane resin, acrylic enamel resin, oxidation-curing alkyd resin, oxidation-curing modified (CAB nato) alkyd resin, room-temperature or heat-curing fluororesin, hydrolyzable nuryl group-containing a-resin, hydroxyl-based white vinyl-based heavy resin Examples include those whose main components are mixtures of polymers and hydrolyzable/lyl group-containing white polymers.

The type of paint may be any type such as a solution type paint using an organic solvent as a medium, a non-aqueous dispersion paint, a multi-component type paint, a powder paint, a slurry paint, or a water-based paint.

The metallic powder and colored pigment may be any known and commonly used ones, and any metallic powder and colored pigment may be used. Examples of metallic powder include aluminum powder, copper powder, and mica powder.
Examples of coloring paints include organic pigments such as phthalocyanine blue, toluidine red, and benzidine yellow, and inorganic pigments such as titanium oxide, carbon black, and hengara. These metallic powders and colored pigments may be used alone or in combination of two or more.

Moreover, ultraviolet absorbers and light stabilizers can be used in the paint containing the metallic powder and/or colored pigment, and by using these, it is possible to further improve weather resistance.

As the ultraviolet absorber, a wide variety of conventionally known ones can be used, and for example, benzophenone-based, triazole-based, phenylsalinlate-based, diphenyl acrylate-based, and acetophenone-based ultraviolet absorbers are preferred.

As the light stabilizer, a wide variety of conventionally known ones can be used,
For example, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,26,6-bentamethyl-4-piperidyl) sebacate, 2-(L5-
tert-butyl-4-hydroxybenzyl)-2
-n-butylmalonate bis(1,2,2,6,8-pentamethyl-4-piperidyl), tetrakis(2°2.6
J-tetramethyl-4-piperidyl)-1,2,3,4
Butane tetracarboxylate, tetrakis (1,2,
2,6,8-pentamethyl-4-piperidyl)-1,2
, 3,4-butanetetracarboxylate, etc. These may be used alone or in combination of two or more.

Furthermore, in paints containing metallic powder and/or colored pigments, in order to improve the adhesion between the paint film and the topcoat clear paint film, the above hydrolyzable silane compounds, condensates thereof, reactants thereof, or It may also contain mixtures thereof. Its content in 100 parts of paint containing metallic powder and/or colored pigment is usually
It is preferable that the amount is 50 parts or less, more preferably 20 parts or less.

Commercially available acrylic melamine may also be blended into the top coat clear paint. However, the curable composition must be included as a main component, that is, at least 5096% of the paint. When the ratio is less than 50%, weather resistance,
Acid resistance decreases.

The above-mentioned ultraviolet absorber and light stabilizer may be added to the top coat clear paint.

By blending these, weather resistance can be significantly improved. Further, by using a UV absorber and a light stabilizer together, weather resistance can be further improved.

The amount of the ultraviolet absorber to be blended is usually 0.1 to 10 parts, preferably 1 to 5 parts, based on 100 parts of the solid content of the top coat clear paint. The amount of light stabilizer is usually 0 parts per 100 parts of the solid content of the top coat clear paint.
1 to IO parts, preferably 1 to 5 parts.

Although there are no particular limitations on the method for producing the coated product of the present invention, for example, a paint containing the metallic powder and/or color pigment is coated on an object, and after setting for a few minutes, wet-on-wet coating is performed. Apply top coat clear paint and heat cure (2 coat/1 area method), or apply paint containing metallic powder and/or coloring pigment and heat cure, then apply top coat clear paint. It can be manufactured by painting and heating and curing (two-coat, two-bake method).

There is no particular limitation on the thickness of the coating film, but the thickness after drying of the coating film containing metallic powder and/or colored pigment is preferably 10 to 30 μm from the viewpoint of hiding properties, and the thickness of the coating film containing the metallic powder and/or color pigment is preferably 10 to 30 μm. The thickness is 20~20cm from the viewpoint of durability.
50 μm is preferred.

The coating film thus formed exhibits excellent performance in terms of appearance and weather resistance.

Examples of objects on which the coating film is formed include buildings,
Examples include automobiles, industrial machinery, steel furniture, home appliances, and plastic products, and it is used for the above-mentioned paints or top coats.

Next, the present invention will be explained in more detail based on Examples.

Production Examples 1 to 2 [Synthesis of epoxy group-containing acrylic resin (A)] Stirrer,
45.9 parts of butyl acetate was charged into a reaction vessel equipped with a thermometer, a reflux condenser, a nitrogen gas introduction tube, and a dropping funnel.
After increasing the temperature to 110°C while introducing nitrogen gas, the first
The mixture shown in the table was added dropwise at a uniform rate over 5 hours using a dropping funnel.

After the addition of the mixture was completed, 05 parts of 2,2-azobisisobutyronitrile and 5 parts of toluene were added dropwise at a uniform rate over 1 hour. After completion of the dropwise addition, the mixture was aged at 110°C for 2 hours.
After cooling, xylene was added to the resin solution to adjust the solid content to 60%.

Table 1 Production Example 3 [Synthesis of siloxane compound (B)] From 100 g of methyltrimethodisilane, 39.7 g of deionized water, which is the amount of water necessary to hydrolyze all the alkoxysilyl groups, and 0.07 g of 6096 hydrochloric acid. The mixture was reacted at 80° C. for 5 hours while the methanol produced was distilled off to obtain a siloxane compound (b-1).

Examples 1-8 and Comparative Example 1.2 Paints (paints 1 to 10) having the compositions shown in Table 2 were prepared.

The test specimen was a mild steel plate that had been degreased and phosphorylated and coated with an automotive-grade epoxyamide cationic electrodeposited primer and intermediate coat surfacer. After a base coat (acrylic melamine resin paint) was applied on top of the coated plate, wet coating was applied.・Top coat clear paint (paints 1 to 10) shown in Table 2 or 2-component acrylic urethane (product name manufactured by Natco Paint ■, Gamelon 5) on or wet.
0■) or acrylic melamine (Hellcoat No. 5700 manufactured by NOF ■) was applied, and after setting for 20 minutes, it was baked at 140°C for 30 minutes. The dry film thickness was approximately 15 μm for the hair coat and approximately 30 μm for the clear top coat. The resulting coated product was evaluated as follows. The results are shown in Table 3.

(Appearance) Comprehensive evaluation of luster and texture is performed visually.

0 indicates good, Δ indicates normal, and X indicates poor.

(Adhesion) A cellophane tape peel test was conducted on the substrate (2 mm x 2 am) and evaluated with 25/25 as 10 points and 0/25 as 0 points, with 8 points or more being considered as passing.

(hardness) Measured in accordance with JIS K 5400.

(Acid resistance) Spot 5 to 6 drops of 38% H2SO4 and leave at room temperature for 24 hours. After wiping it off, examine the traces and evaluate them according to the criteria below.

○: No abnormality △: Traces or remains are slightly shiny and pickled ×: Completely shiny and pickled (weather resistance) Using Yubucon manufactured by Atlas, UV irradiation was performed at 70°C for 8 hours, and water condensation (dark) at 50°C. In a 4 hour cycle,
An accelerated test is conducted for 2500 hours, and the gloss retention rate is evaluated.

(Pot life) The paints shown in Table 2 are left open at room temperature and observed for gelation or crispness on the surface.

(Gel fraction) Each paint is applied onto a fluorine film and baked at 140° C. for 30 minutes to produce a film with a thickness of 30 μm.

The gel fraction of the obtained film was evaluated using the acetone extraction method.

Example 9 A coated product was prepared in the same manner as in Example 2, except that a base coat prepared by adding 10 parts of KR213 to 100 parts of the acrylic melamine resin paint was used, and the properties were evaluated. The results are shown in Table 3.

[Margin below]

From the results shown in Table 3, it can be concluded that the paint made from the composition of the present invention is superior in terms of pot life, which is a problem with conventional acrylic urethane, and acid resistance and weather resistance, which are problems with acrylic melamine. Recognize.

〔Effect of the invention〕

When the curable composition of the present invention is used, it is non-isocyanate-based, is a one-component composition, and can be applied to coated objects having a coating film with excellent weather resistance, chemical resistance, hardness, and adhesion.

Claims (1)

[Claims] 1. A curable composition comprising (A) a compound having two or more epoxy groups in its molecule, (B) a siloxane compound having two or more silanol groups in one molecule, and (C) an organic zirconium compound. thing. 2 Compounds having two or more epoxy groups in one molecule (A
2. The curable composition according to claim 1, wherein ) is an epoxy group-containing acrylic resin. 3. The curable composition according to claim 1, wherein the organic zirconium compound (C) is an organic zirconium compound containing at least one alkoxy group. 4. A painted object coated with a paint containing a metallic powder and/or a colored pigment, and a top coat clear paint coated on the painted surface, the top coat clear paint comprising the composition according to claim 1. A painted product characterized by having a curable paint as its main component. 5. The coated product according to claim 4, wherein the top coat clear paint contains an ultraviolet absorber and/or a light stabilizer. 6. The coated product according to claim 4, wherein the paint containing metallic powder and/or colored pigment contains a hydrolyzable silane compound, a condensate thereof, a reactant thereof, or a mixture thereof.