JP2001123119A - Coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating composition capable of forming a coating film excellent in frost damage resistance, hot water resistance, adhesion or the like. SOLUTION: This coating composition is obtained by using a product obtained by reacting a mixture comprising (a) 100 pts.wt. an organosilane represented by formula (1): (R1)nSi(OR2)4-n [wherein, R1 is a 1-8C organic group; R2 is a 1-5C alkyl group; and n is 1 or 2] and/or a partial hydrolysis condensate, (b) 1-280 pts.wt. silyl group-containing organic compound represented by formula (2) [wherein, R1 and R2 are the same as the before; A is (CH2)m; m is an integer of 1-8; and n is 0, 1 or 2] and (c) 2-200 pts.wt. silyl group-containing vinyl-based resin having a hydrolyzable silyl group or a silicone atom bonded to a hydroxy group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition for forming a coating film having excellent frost damage resistance (crack resistance), hot water resistance, weather resistance, stain resistance and adhesion.

[0002]

2. Description of the Related Art In recent years, coating compositions using an organopolysiloxane as a binder for forming a coating film having excellent weather resistance and stain resistance have been widely used. Such coating compositions are disclosed in, for example, JP-A-60-51756, JP-A-1-126, JP-A-3-221577, and JP-A-4-117473. However, the coating composition using an organopolysiloxane as a binder has a problem that the resulting coating film has poor frost resistance, hot water resistance and the like. Therefore, a co-polymer containing a silyl group-containing vinyl resin in combination is used.
Although a tinting composition has been developed, it also has a problem that the frost resistance, hot water resistance, adhesion to an organic substrate, and the like are insufficient.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and has been described as having resistance to frost damage,
An object of the present invention is to provide a coating composition capable of forming a coating film having excellent hot water resistance and excellent adhesion to an organic substrate.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies in order to achieve the above object, and as a result, have found that the above object can be achieved by the following constitution, and have reached the present invention. That is, the present invention relates to (a) Formula (1) (R ¹ ) _n Si
(OR ² ) _{4-n wherein} R ¹ is an organic group having 1 to 8 carbon atoms, R ² is an alkyl group having 1 to 5 carbon atoms, and n
Is 1 or 2. 100 parts by mass of one or both of the organosilane and the partially hydrolyzed condensate thereof
(b) Equation (2)

[0005]

Embedded image

[Wherein, R ¹ and R ² have the same meanings as above, A is (CH ₂ ) _m , m is an integer of 1 to 8,
n is 0, 1 or 2. 1 to 280 parts by mass of a silyl group-containing organic compound represented by the formula: and (c) a silyl group-containing vinyl resin having a hydrolyzable silyl group or a silyl group having a silicon atom bonded to a hydroxyl group, and 2 to 200 parts by mass. A coating composition containing, as a binder, a product obtained by reacting a mixture consisting of

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. First, each component used for producing the binder of the coating composition of the present invention will be described. Component (a) The component (a) is represented by the formula (1) (R ¹ ) _n Si (OR ² ) _{4-n wherein} R ¹ is an organic group having 1 to 8 carbon atoms, and R ² is It is an alkyl group having 1 to 5 carbon atoms, and n is 1 or 2. And / or a partially hydrolyzed condensate thereof. R ¹ in the above formula has 1 to 1 carbon atoms.
8, preferably 1 to 6 organic groups. Examples of the organic group include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group and the like. Here, the alkyl group may be linear or branched. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a pentyl group, a hexyl group, and an octyl group. Preferred alkyl groups have 1 to 4 carbon atoms.
belongs to. The alkenyl group may be linear or branched. Examples of the alkenyl group include a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, and an octenyl group. Preferred alkenyl groups have 2 to 4 carbon atoms.

Preferred examples of the cycloalkyl group include a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and a cyclononyl group. Further, as the aryl group, for example, a phenyl group and the like are preferably mentioned. Each of the above functional groups may optionally have a substituent. Examples of such a substituent include a halogen atom, an epoxy group, a mercapto group, a cycloalkyl group, an amino group, and the like. Examples of the organic group having such a substituent include a γ-chloropropyl group and 3,
3,3-trifluoropropyl group, γ-glycidoxypropyl group, γ-mercaptopropyl group, 3,4-epoxycyclohexylethyl group, γ-aminopropyl group and the like. When the R ¹ there are a plurality, these R ¹
May be the same or different. R ² in the formula is an alkyl group having 1 to 5 carbon atoms. The alkyl group may be linear or branched. As such an alkyl group,
For example, methyl group, ethyl group, n-propyl group, i-
Examples include a propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, and a pentyl group. Preferred alkyl groups have 1 to 2 carbon atoms.
When a plurality of R ² are present, these R ² may be the same or different.

As the organosilane represented by the above formula (1), for example, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltrimethoxysilane Ethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane,
γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxy Silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ- Mercaptopropyltriethoxysilane,
Phenyltrimethoxysilane, phenyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3,4
-Epoxycyclohexyltrimethoxysilane, 3,4
-Epoxycyclohexylethyltriethoxysilane,
Dimethyl dimethoxy silane, dimethyl diethoxy silane, diethyl dimethoxy silane, diethyl diethoxy silane, diphenyl dimethoxy silane, diphenyl diethoxy silane, methyl phenyl dimethoxy silane, dimethyl dipropoxy silane and the like, preferably, methyl trimethoxy silane, Methyltriethoxysilane and dimethyldimethoxysilane. These organosilanes can be used alone or as a mixture of two or more.

The component (a) may be a partially hydrolyzed condensate of the organosilane described above. The polystyrene equivalent weight average molecular weight of the condensate is 300 to 5,000,
Preferably, 500 to 3,000 is suitable. By using a condensate having such a molecular weight, a coating film having good adhesion can be obtained without deteriorating storage stability. Furthermore, partial hydrolysis condensate of organosilane, a -OH group or -OR ² group bonded to a silicon atom 1 or more, and preferably those having 3 to 30. Specific examples of such a condensate include commercial products such as SH6018, SR2402, and DC303 manufactured by Dow Corning Toray.
7, DC3074; KR-211 manufactured by Shin-Etsu Chemical Co., Ltd.
KR-212, KR-213, KR-214, KR-2
16, KR-218; TSR-1 manufactured by Toshiba Silicone Co., Ltd.
45, TSR-160, TSR-165, YR-318
7 and the like. In the present invention, in order to improve the storage stability and the like of the coating composition in combination with the component (a), the formula (3) (R ¹ ) ₃ Si (OR ² ) [wherein R ¹ and R ² have the same meaning as in the formula (1) of the component (a). And the organosilane represented by the formula (a)
It is also possible to mix in a range not exceeding 20 parts by mass with respect to parts by mass. Specific examples of such an organosilane include, for example, methoxytrimethylsilane, ethoxytrimethylsilane, ethoxydiphenylmethylsilane, methoxydimethylvinylsilane and the like.

(B) Component (b) The component is represented by the formula (2)

[0012]

Embedded image

[0013] wherein, R ¹ and R ² are the same meaning as R ¹ and R ² of component (a) of the formula (1), A, (C
H ₂ ) _m , where m is an integer from 1 to 8, n is 0,
1 or 2. And a silyl group-containing organic compound represented by the formula: Specific examples of these silyl group-containing organic compounds include 1,3,5-tris (2-trimethoxysilylethyl) isocyanurate and 1,3,5-N-tris (3-
Triethoxysilylpropyl) isocyanurate, 1,
3,5-N-tris (3-trimethoxysilylpropyl) isocyanurate, 1,3,5-N-tris (3-
Methyl-3-dimethoxysilylpropyl) isocyanurate, 1,3,5-N-tris (3-dimethyl-3-methoxysilylpropyl) isocyanurate, and the like. These silyl group-containing organic compounds may be used alone. Or a mixture of two or more. As a commercially available product of such a silyl group-containing organic compound, for example, Y-11597 manufactured by Nihon Unica Co., Ltd. and the like can be mentioned. The component (b) is 1 component per 100 parts by mass of the component (a).
280, preferably 20 to 200 parts by mass. If the amount is less than the above range, the frost damage resistance and the adhesion to an organic base material are deteriorated, and if the amount is too large, the weather resistance and the like are deteriorated. Not preferred.

Component (c) As the component (c), at least one, preferably two, hydrolyzable silyl groups or silyl groups having a silicon atom bonded to a hydroxyl group at the terminal or side chain in one resin molecule. Having a molecular weight of, for example, about 1,000 to 5
It is suitable that the resin is a vinyl-based resin of 000, preferably 1,500 to 10,000. The silyl group is represented by the formula (4) -SiX _P (R ³ ) _{(3-P) wherein} X is an alkoxy group, an acyloxy group, a halogen atom, a ketoximate group, an amino group, an acid amide group, an amideoxy group, A hydrolyzable group such as a mercapto group, an alkenyloxy group, a phenoxy group or a hydroxyl group; R ³ is a hydrogen atom or a carbon atom
10 is a monovalent hydrocarbon group such as an alkyl group, an aryl group, and an aralkyl group, and P is an integer of 1 to 3.]. Examples of the silyl group-containing vinyl resin include the following formulas (5) and (X) _P (R ³ ) _(3-P) Si—H wherein X, R ³ and p have the same meanings as described above. And a vinyl-based resin having a carbon-carbon double bond in a conventional manner.

The hydrosilane compound includes:
For example, typical examples include methyldichlorohydrosilane, methyldiethoxyhydrosilane, methyldiacetoxyhydrosilane, and methyldiaminooxyhydrosilane. The amount of the hydrosilane compound is suitably 0.5 to 2 times the molar amount of the carbon-carbon double bond contained in the vinyl resin. The vinyl resin includes methyl (meth) acrylate, ethyl (meth) acrylate,
(Meth) acrylic acid esters such as butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and cyclohexyl (meth) acrylic acid; carboxylic acids such as (meth) acrylic acid, itaconic acid, and fumaric acid; and maleic anhydride An acid anhydride such as glycidyl (meth) acrylate; a copolymer of a vinyl monomer selected from the group consisting of acrylonitrile, styrene, α-methylstyrene, vinyl acetate, vinyl propionate and the like. During the production of the copolymer, allyl (meth) acrylate or diallyl phthalate is subjected to radical copolymerization to form a carbon-containing compound for a hydrosilylation reaction in a vinyl resin.
It is possible to introduce a carbon double bond.

Other production methods include the above-mentioned vinyl monomers, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
A hydroxyl group-containing monomer such as 2-hydroxyvinyl ether, γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryloxypropyltriethoxysilane, β- (meth) acryloxyethyltrimethoxysilane, β- ( (Meth) acryloxyethyltriethoxysilane, γ- (meth) acryloxypropylmethyldimethoxysilane, γ- (meth) acryloxypropylmethyldiethoxysilane, γ- (meth) acryloxypropylmethyldipropoxysilane, γ- ( (Meth) acryloxybutylphenyldimethoxysilane, γ- (meth) acryloxybutylphenyldiethoxysilane, γ- (meth) acryloxypropyldimethylmethoxysilane, γ
There is also a method of radically polymerizing a silyl group-containing vinyl compound such as-(meth) acryloxypropyldiethylmethoxysilane. Specific examples of these silyl group-containing vinyl resins include, for example, Kanekazemulak manufactured by Kaneka Corporation as a commercially available product.

The component (c) is suitably used in an amount of 2 to 200 parts by mass, preferably 10 to 150 parts by mass, per 100 parts by mass of the component (a). If the amount used is less than the above range, the appearance of the obtained coating film and the alkali resistance and the like are deteriorated. Conversely, if the amount is too large, the weather resistance of the obtained coating film and the storage stability of the composition are unfavorably deteriorated. . The binder for the coating composition of the present invention is produced by subjecting the components (a), (b) and (c) described above to hydrolysis and partial condensation in the presence of, for example, water and a catalyst. be able to. The amount of water is 0.2 to 1.0 equivalent, preferably 0.3 to 0. 1 equivalent to 1 equivalent of the hydrolyzable functional group in the components (a), (b) and (c). 8 equivalents are suitable. Examples of the catalyst include inorganic acids such as nitric acid and hydrochloric acid; and organic acids such as acetic acid, formic acid and propionic acid. The amount of the catalyst is suitably such that the pH of the composition becomes 3 to 6. The binder can be produced by mixing the component (a), the component (b), and the component (c) in the presence of water and a catalyst, for example, at 40 to 80 ° C, preferably at 45 to 65 ° C for 2 to 1
A method of reacting for 5 hours is preferable. Alternatively,
A Zr, Ti or Al-based metal chelate compound catalyst is added in combination with or without the above-mentioned catalyst comprising an inorganic acid or an organic acid, and comprises a component (a), a component (b) and a component (c). The mixture can be produced by a hydrolysis-condensation reaction in the presence of water.

Specific examples of the metal chelate compound catalyst include zirconium tri-n-butoxyethylacetoacetate, zirconium di-n-butoxydi (ethylacetoacetate), zirconium tetrakis (acetylacetoacetate), and tetrakis (ethylacetoacetate). Zirconium chelate compounds such as zirconium; titanium chelate compounds such as diisopropoxybis (acetylacetate) titanium and diisopropoxybis (ethylacetoacetate) titanium; diisopropoxyethylacetoacetate aluminum, diisopropoxyacetylacetonatoaluminum, iso Aluminization of propoxybis (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, etc. Things and the like. The metal chelate compound catalyst comprises (a) component, (b) component and (c)
It is used to promote the condensation reaction between the components and improve the appearance of the coating film, weather resistance, stain resistance and the like. Therefore, the metal chelate compound is added in an amount of 0.1 to 100 parts by mass of the component (a).
It is suitable to use from 01 to 50 parts by mass, preferably from 0.1 to 15 parts by mass. The amount of water depends on the component (a),
(B) component, (c) 0.2 to 1.0 equivalent to 1 equivalent of the hydrolyzable functional group in the metal chelate compound,
Preferably, 0.3 to 0.8 equivalent is appropriate. The reaction temperature and reaction time can be performed under the same conditions as in the above-mentioned method.

The coating composition of the present invention contains the above-described reaction product as a binder, and further adjusts the solid content of the composition to preferably about 5 to 50% by mass, if necessary. The composition comprises a solvent, a filler, various additives such as a dye, a curing accelerator, a thickener, and a pigment dispersant for improving the storage stability and coating workability of the composition. Examples of the solvent include alcohols such as methanol, ethanol, propanol and butanol, alcohol ethers such as ethylene glycol monoethyl ether and ethylene glycol monobutyl ether, and ketones such as acetone and methyl ethyl ketone. In addition to the hydrophilic organic solvent, various coating organic solvents such as toluene, xylene, ethyl acetate, and butyl acetate can be used.

As the filler, for example, talc,
Various extenders and coloring pigments for coatings such as barium carbonate, calcium carbonate, barium sulfate, bentonite, titanium oxide, carbon rack, red iron, lithopone and the like can be used. Examples of the curing accelerator include, for example, tin octylate, dibutyltin dilaurate, organic tin compounds such as dibutyltin dimaleate, tributyltin laurate, and amine compounds such as ethylenediamine, diethylenetriamine, piperidine, phenylenediamine, and triethylamine. Although an organic tin compound is particularly effective. These curing accelerators are desirably added to cure the coating composition at a relatively low temperature and at a higher speed.
0.01 to 15 parts by mass is appropriate for 00 parts by mass. The coating composition of the present invention is capable of forming a cured coating film by coating the surface of an object to be coated with a coating means such as brush, spray, roll, dipping and baking at room temperature or at a temperature of 300 ° C. or less. is there. The object to be coated can be applied to various objects to be coated such as an inorganic ceramic substrate, various metal substrates such as stainless steel and aluminum, a glass substrate, a plastic substrate, and a paper substrate.

[0021]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, “parts” and “%” are shown on a mass basis unless otherwise specified. <Preparation of Silyl Group-Containing Vinyl Resin Solution (A)> To a reactor equipped with a reflux condenser and a stirrer, 45 parts of xylene and 40 parts of isobutanol were added, mixed, and heated to 85 ° C. with stirring. Heated. Next, 50 parts of isobutyl methacrylate, 35 parts of 2-ethylhexyl methacrylate, γ
-Methacryloxypropyltrimethoxysilane 15 parts,
And a mixed solution of azobisisovaleronitrile and 1.5 parts of azobisisovaleronitrile were added dropwise at 85 ° C. over 3 hours. Thereafter, the temperature was raised to 90 ° C. and maintained for 2 hours to terminate the reaction. The obtained silyl group-containing vinyl resin solution (a) has a solid content of 55%.
The number average molecular weight of the resin was 14000, and the polymer had an average of about 7 silyl groups per molecule.

Example 1 In a reactor equipped with a reflux condenser and a stirrer, (a) a partially hydrolyzed condensate of methyltrimethoxysilane (SR2402 manufactured by Dow Corning Toray Industries; solid content 100%)
0 parts, 60 parts of methyltrimethoxysilane and 10 parts of dimethyldimethoxysilane, (b) 20 parts of 1,3,5-N-tris (3-trimethoxysilylpropyl) isocyanurate, and (c) vinyl containing a silyl group. Resin solution (Kaneka Zemulak, manufactured by Kaneka Chemical Industry Co., Ltd .; solid content: 50)
%), 25 parts of diisopropoxyaluminum ethyl acetoacetate and 20 parts of isopropanol were added and mixed, and 13.3 parts of ion-exchanged water was added.
The reaction was carried out at 60 ° C. for 3 hours.
0 and cooled to room temperature. Composition A (34% solids)
I got

Example 2 In a reactor equipped with a reflux condenser and a stirrer, 25 parts of (a) a partially hydrolyzed condensate of methyltrimethoxysilane (SR2402 manufactured by Dow Corning Toray), methyltrimethoxy Silane 65 parts, dimethyldimethoxysilane 10
Parts and 1 part of trimethylmethoxysilane, (b) 1,
40 parts of 3,5-N-tris (3-trimethoxysilylpropyl) isocyanurate, (c) 50 parts of a silyl group-containing vinyl resin solution (a), and 1 part of diisopropoxyaluminum ethyl acetoacetate After adding and mixing 20 parts of isopropanol, 1 part of ion-exchanged water is added.
5 parts were added and reacted at 60 ° C. for 4 hours. Further, 140 parts of isopropanol was added, and the mixture was cooled to room temperature.
(Solid content 35%) was obtained.

Example 3 A reactor equipped with a reflux condenser and a stirrer was charged with (a) 40 parts of a partially hydrolyzed condensate of methyltrimethoxysilane (SR2402 manufactured by Dow Corning Toray Co., Ltd.), 50 parts of silane, dimethyldimethoxysilane 10
Part, and 1 part of trimethylmethoxysilane, (b) 1,
3,5-N-tris (2-trimethoxysilylethyl)
70 parts of isocyanurate, 25 parts of (c) a silyl group-containing vinyl resin solution (Kanekazemulac Co., Ltd., 50% solids), and diisopropoxyaluminum ethyl acetoacetate After 5 parts and 50 parts of isopropanol were added and mixed, 16 parts of ion-exchanged water was added, reacted at 60 ° C. for 3 hours, further added with 150 parts of isopropanol, and cooled to room temperature.
(Solid content 35%) was obtained.

Comparative Example 1 In a reactor equipped with a reflux condenser and a stirrer, 25 parts of (a) a partially hydrolyzed condensate of methyltrimethoxysilane (SR2402 manufactured by Dow Corning Toray), Silane 65 parts, dimethyldimethoxysilane 10
And 1 part of trimethylmethoxysilane, (c) 90 parts of a silyl group-containing vinyl resin solution (a), and 1 part of diisopropoxyaluminum ethyl acetoacetate, and 20 parts of isopropanol, and after mixing, 15 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours. Further, 80 parts of isopropanol was added, and the mixture was cooled to room temperature.
A composition D (solid content 35%) was obtained.

<Performance Evaluation Test> Preparation of a test plate: A gypsum slag perlite plate (12 mm thick) was used as a raw material, and a polyisocyanate prepolymer solution sealer “V-Selan 100 sealer” (Dainippon Paint Co., Ltd.) was used on the surface. (Product name) (a product diluted 100% with a solvent of butyl acetate: xylene = 1: 1) was spray-coated so that the coating amount was 90 to 100 g / m ² (wet mass). This was dried at 100 ° C. for 5 minutes. Next, an acrylic silicone resin-based paint “V-Seran @ 500 Enamel” (trade name, manufactured by Dainippon Paint Co., Ltd.) was used as a base coat paint (butyl acetate: xylene = 1: 1 solvent).
% Diluted product) was spray-coated so that the coating amount was 80 to 90 g / m ² (wet mass). This at 120 ° C for 15
Dried for minutes. Next, the coating composition shown in Table 1 (the numerical values in the table indicate "parts") obtained by adding an organic solvent, a curing accelerator, and the like to each of the above-described compositions was applied in an amount of (130).
The composition was spray-coated so as to be ± 10) g / m ² (wet mass). This is dried at 120 ° C. for 15 minutes, and then dried at room temperature for 3 minutes.
Dried for days. Each of the obtained coating films was tested for frost resistance, hot water resistance, stain resistance, and weather resistance, and the results are shown in Table 1. In addition, the adhesion was tested by the following method, and the results are shown in Table 1.

The test method and evaluation criteria are as follows. Freezing damage resistance: Measured by ASTEM-C66A method Evaluation criteria…: No cracks generated…: Extremely slight cracks generated…: Cracks generated or partial peeling of coating film ×: Significant cracks, peeling of coating film The film was immersed in tap water at 60 ° C. for 10 days, and the appearance of the coating film was visually observed. Evaluation criteria ○: no change △: slight change such as gloss reduction, whitening, etc. ×: large change such as gloss reduction, whitening, etc.

Stain resistance: Twenty-four hours after the application of Red and Black Magic Ink (registered trademark), the stain was wiped off with a cloth wetted with n-butanol, and the stain resistance was visually observed. Evaluation criteria…: Complete removal 極: Very slight contamination…: Contamination ×: Significant contamination Weather resistance: Sunshine Weather-O-Meter 3000
After a lapse of time, the appearance of the coating film was observed. Evaluation criteria ○: no change in appearance of coating film, gloss retention of 95% or more…: slight change in appearance of coating, gloss retention of 80 to 94
% Or more ×: The appearance of the coating film changed significantly, and the gloss retention was less than 80%.

[Adhesion to Inorganic Substrate] Gypsum slag perlite plate (thickness: 12 mm) was used.
Was applied at 90 to 100 g / m ² and dried at 120 ° C. for 15 minutes. The coating film was cross-cut with a cutter, a cellophane tape was stuck and peeled off, and the adhesion was compared. Evaluation criteria…: no change…: extremely slight peeling 少 し: slight peeling…: many peeling parts [Adhesion to organic coating film] Polyurethane paint V was applied to the top coat according to the method for preparing a test plate in the above-mentioned performance evaluation test. About 110 g / m ^{2 of the} top white (trade name, manufactured by Dainippon Paint Co., Ltd.) was applied and left at room temperature for 7 days.
The test plate was coated with the coating composition shown in Table 1 at 80 to
90 g / m ^{2 was} spray-coated and dried at 120 ° C. for 15 minutes. The adhesion between the organic coating film (V top white) of the test plate and the coating composition coating film after 2 hours of immersion in boiling water was compared. The adhesion was measured in the same manner as the adhesion to the inorganic substrate.

[Table 1] As is clear from Table 1, Examples 1 to 3 using the coating composition of the present invention had excellent coating film performance. On the other hand, Comparative Example 1 which is a coating composition containing no component (b) of Comparative Example 1 was inferior in frost damage resistance, hot water resistance, and adhesion to an organic coating film.

The coating composition of the present invention can form a coating film excellent in frost damage resistance, hot water resistance, weather resistance, stain resistance, adhesion and the like.

Continuation of the front page (72) Inventor Hiroharu Sasaki 7-1414-46 Shimonagata, Nishinasuno-machi, Nasu-gun, Tochigi F-term (reference) 4J035 GA02 HA03 LB01 4J038 CL001 DL031 DL032 DL081 DL082 DL111 DL112 GA01 GA03 GA06 GA08 GA15 HA156 KA04 NA03 NA04 NA05 NA11 NA12 NA14

Claims (2)

[Claims] (A) Formula (1) (R ¹ ) _n Si (OR ² ) _4-n
[Wherein, R ¹ is an organic group having 1 to 8 carbon atoms, and R ² is
It is an alkyl group having 1 to 5 carbon atoms, and n is 1 or 2. 100 parts by mass of one or both of the organosilane represented by the formula (1) and the partially hydrolyzed condensate thereof, and (b) the formula (2) Wherein R ¹ and R ² have the same meaning as described above, and A is
(CH ₂ ) _m , where m is an integer of 1 to 8, and n is
0, 1 or 2. 1 to 280 parts by mass of a silyl group-containing organic compound represented by the formula: and (c) a silyl group-containing vinyl resin having a hydrolyzable silyl group or a silyl group having a silicon atom bonded to a hydroxyl group, and 2 to 200 parts by mass. A coating composition containing, as a binder, a product obtained by reacting a mixture consisting of 2. A coating composition wherein the reaction according to claim 1 is carried out in the presence of water and a catalyst.