JP3017970B2 - Method for producing organic-inorganic composite resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an organic-inorganic composite resin without using a metal chelate compound and a chelating agent, and a method for producing an organic-inorganic composite resin which contains the organic-inorganic composite resin as a binder. The present invention relates to a coating composition having excellent stainability, hot water resistance and the like.

[0002]

2. Description of the Related Art A coating film comprising an organic-inorganic composite resin obtained by subjecting an organosilane and / or a partially hydrolyzed condensate thereof and a silyl group-containing vinyl resin to a hydrolytic condensation reaction has a weather resistance, As a coating composition using an organic-inorganic composite resin as a binder is attracting attention, it is excellent in stain resistance and the like, and hardly cracks like a coating film using an organopolysiloxane-based inorganic resin as a binder. It is becoming. By the way, conventionally, organosilane and / or
Or, in order to cause a hydrolysis-condensation reaction between the partially hydrolyzed condensate and a silyl group-containing vinyl resin, Zr, T
i or Al based metal chelate compound is used. However, the coating composition using an organic-inorganic composite resin obtained by using a metal chelate compound as a binder is combined with a chelating agent such as acetylacetone or ethyl acetoacetate to improve storage stability. Therefore, when a metal container made of iron or the like is used as a storage container, there is a problem that the chelating agent is chelated with the metal container and tends to corrode the metal container, so that the metal container cannot be used. Was. In fact, there is also concern about corrosion of metal coating machines.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and provides a method for producing an organic-inorganic composite resin without using a metal chelate compound and a chelating agent. An object of the present invention is to provide a coating composition using the organic-inorganic composite resin as a binder and having excellent weather resistance, stain resistance, hot water resistance and the like.

[0004]

That is, the present invention relates to the following inventions. 1. (I) (a) Formula _{^{(1), R 1 n Si}} (OR 2) in _4-n [wherein, R ¹ is an organic group having 1 to 8 carbon atoms, R ² is C1-5 And n is 1 or 2. (B) a silyl group-containing vinyl resin having a hydrolyzable silyl group or a silyl group having a silicon atom bonded to a hydroxyl group; 200 parts by weight,
Of the hydrolyzable functional groups in the mixture
A step of conducting a hydrolysis-condensation reaction so that 5 to 80% is reacted, and then (II) a total of the reaction product obtained in the step (I) and the components (a) and (b) remaining unreacted. Quantity 1
The formula (2), B (OR ³ ) ₃ [wherein R
³ is an alkyl group having 1 to 4 carbon atoms. A) adding 0.001 to 3 parts by weight of a trialkoxyborane represented by the formula (1) and subjecting it to a hydrolysis condensation reaction.

[0005] 2. A coating composition containing the organic-inorganic composite resin obtained in the above 1 as a binder.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. Each component used for producing the organic-inorganic composite resin of the present invention will be described. (A) Component 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 a carbon atom. It is an alkyl group of Formulas 1 to 5, and n is 1 or 2. And / or a partially hydrolyzed condensate thereof. In the above formula, examples of the organic group as R ¹ include an alkyl group, a cycloalkyl group, an aryl group, and a vinyl group.

Here, the alkyl group may be linear or branched. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a pentyl group, a hexyl group, and a heptyl group. And an alkyl group such as an octyl group. Preferred alkyl groups have, for example, 1 to 4 carbon atoms. Examples of the cycloalkyl group include a cyclohexyl group, a cycloheptyl group, a cyclooctyl group,
Preferable examples include a cyclononyl group. Further, as the aryl group, for example, a phenyl group, a naphthyl group and the like are preferably mentioned. Each of the above functions may optionally have a substituent. Examples of such a substituent include a halogen atom (eg, a chlorine atom, a bromine atom, a fluorine atom, etc.), a vinyl group, a (meth) acryloyl group, a glycidyl group, a mercapto group, an epoxy group, an alicyclic group And an amino group.

R ¹ is, for example, an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a γ-chloropropyl group, a vinyl group, a 3,3,3-trifluoropropyl group, a γ A glycidoxypropyl group,
γ-methacryloxypropyl group, γ-mercaptopropyl group, phenyl group, 3,4-epoxycyclohexylethyl group, γ-aminopropyl group and the like. R
The alkyl group as ² may be linear or branched. As the alkyl group, specifically, for example,
Methyl group, ethyl group, propyl group, isopropyl group,
Alkyl groups such as an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group and a pentyl group are preferred. Preferred alkyl groups have, for example, 1 to 2 carbon atoms.

Specific examples of the organosilane represented by the above formula (1) include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyl Triethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane,
γ-chloropropylmethoxysilane, γ-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane Γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercapto Propyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3,4-
Epoxycyclohexylethyltrimethoxysilane,
3,4-epoxycyclohexylethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, dimethoxymethylphenylsilane, dimethyldipropoxysilane and the like. However, preferred are methyltrimethoxysilane, methyltriethoxysilane and dimethyldimethoxysilane.

These organosilanes can be used alone or in combination 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, for example, 300 to 5,000, preferably 500 to 3,000, and by using a condensate having such a molecular weight, storage stability is not impaired. A coating film having good adhesion can be obtained. Also,
Partially hydrolyzed condensate of the organosilane, an -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 condensates include commercially available products such as SH6018 manufactured by Dow Corning Toray, SR2402, and DC303.
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, the component (a) is represented by the above formula
(1) of an organosilane having an n value of 1 and / or a partially hydrolyzed condensate thereof (a-1) and an organosilane having an n value of 2 and / or a partially hydrolyzed condensate thereof (a-2) The weight ratio is (50:50 to 100: 0), preferably (6
The mixture of 0:40 to 95: 5) is desirable because it is polymerized stably when producing the binder and a coating film having good crack resistance can be obtained. Component (b) The component (b) has at least one, preferably two or more, hydrolyzable silyl groups at the terminals or side chains or a silyl group having a silicon atom bonded to a hydroxyl group in one molecule of the resin. And the molecular weight is, for example, about 1000 to 500
It is appropriate to use a vinyl resin having a size of from 00, preferably from 1500 to 10000.

[0012] The silyl group of the formula (2), -SiX _P (R
³ ) _{(3-P) wherein} X is a hydrolyzable group such as an alkoxy group, an acyloxy group, a halogen atom, a ketoximate group, an amino group, an acid amide group, an amideoxy group, a mercapto group, an alkenyloxy group, and a phenoxy group. R ³ is a hydrogen atom or a monovalent hydrocarbon group such as an alkyl group having 1 to 10 carbon atoms, an aryl group, an aralkyl group, etc., and p is an integer of 1 to 3. ]. Examples of the silyl group-containing vinyl resin include those represented by the formulas (3), (X _P ) (R ³ ) _(3-p) Si—H wherein X, R ³ and p are the same as described above. And a vinyl-based resin having a carbon-carbon double bond.

Typical examples of the hydrosilane compound include methyldichlorosilane, methyldiethoxysilane, methyldiacetoxysilane, and methyldiaminooxysilane. 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, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and cyclohexyl (meth) acrylate.
(Meth) acrylates such as acrylic acid; (meth)
Carboxylic acids such as acrylic acid, itaconic acid and fumaric acid and acid anhydrides such as maleic anhydride; epoxy compounds such as glycidyl (meth) acrylate; acrylonitrile, styrene, α-methylstyrene, vinyl acetate, vinyl propionate and the like This is a copolymer of a vinyl monomer selected from the group. The copolymer is produced by radical copolymerization of allyl (meth) acrylate or diallyl phthalate during the production of the copolymer, so that a hydrosilylation reaction occurs in the vinyl resin. Can be introduced.

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- ( There is also a method of radically polymerizing a silyl group-containing vinyl compound such as (meth) acryloxybutylphenyldimethoxysilane, γ- (meth) acryloxypropyldimethylmethoxysilane, and γ- (meth) acryloxypropyldiethylmethoxysilane.

Specific examples of these silyl group-containing vinyl resins include commercially available products such as Kanekazemurak manufactured by Kaneka Corporation. The method for producing the organic-inorganic composite resin of the present invention will be described. First, in the step (I), the component (a) and the component (b) are subjected to a hydrolysis and condensation reaction in the presence of water and a catalyst. (A) component and (b)
The mixing ratio with the component is 100 parts by weight of the former and 2 to 200 parts by weight, preferably 10 to 150 parts by weight of the latter. In addition, when the latter is less than the above range, the appearance and crack resistance of the obtained coating film, frost damage resistance, alkali resistance, etc. are deteriorated, and when too large, the weather resistance of the obtained coating film and the storage stability of the composition are deteriorated. It is not preferable because the properties are deteriorated.

In the step (I), the amount of water is as follows:
(B) 45 to 8 of the hydrolyzable functional group in the mixture with the component
0%, preferably 50 to 70%, is hydrolyzed and condensed to 0.4 to 0.9 with respect to 1 equivalent of the hydrolyzable functional group.
An equivalent amount, preferably an amount equivalent to 0.5 to 0.8 equivalent is appropriate. 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 catalyst depends on the p of the coating composition.
An amount such that H becomes 3 to 6 is appropriate. The hydrolysis-condensation reaction is carried out by mixing the component (a) and the component (b) in the presence of water and a catalyst, to form a mixture at 40 to 80 ° C, preferably 45 to 65 ° C.
The reaction is preferably carried out for 2 to 5 hours, but the method is not limited to this method.

In the hydrolysis and condensation reaction in the step (I), the reaction of the component (a) mainly occurs due to the reaction rate,
The reaction between the component (b) or the component (a) and the component (b) (grafting reaction by a condensation reaction) is slow. In addition, as mentioned above, in the step (I), the hydrolysis and condensation reaction are performed at 45 to 80% of the hydrolyzable functional group in the mixture of the component (a) and the component (b) because This is because the storage stability of the product is good and a highly transparent film can be formed. When the content is less than 45%, a film having poor transparency is formed, resulting in poor appearance. It is not preferable because the property deteriorates. Subsequent to the step (I), in the step (II), water and water of the formula (2) B (OR ³ ) ₃ [wherein R
₃ is an alkyl group having 1 to 4 carbon atoms. ], And a hydrolysis and condensation reaction are performed.

The amount of water is at least 1 equivalent, preferably 1.2 to 2 equivalents per 1 equivalent of the remaining hydrolyzable functional group after the hydrolysis and condensation reaction in step (I). is there. The trialkoxyborane represented by the above formula (2) includes, for example, trimethoxyborane, triethoxyborane, tripropoxyborane, tributoxyborane and the like. The trialkoxyborane can be obtained by (a)
It is used for accelerating the condensation reaction between the component and the component (b) and improving the appearance, weather resistance, stain resistance, hot water resistance and the like of the coating film. Therefore, the amount of trialkoxyborane is
0.001 to 3 parts by weight, preferably 0.005 parts by weight, based on 100 parts by weight of the total of the reaction product obtained in the step (I) and the components (a) and (b) remaining unreacted. ~ 1
Parts by weight are appropriate. If the amount of trialkoxyborane is less than the above range, the condensation reaction will be insufficient, and the above-mentioned effect of improvement will not be obtained. Conversely, if the amount is too large, the reaction stability will be poor, which is not preferable.

The hydrolysis-condensation reaction in the step (II) includes:
As in the step (I), 40 to 80 ° C., preferably 45 to 80 ° C.
It is appropriate to react at 65 ° C., for example, for 2 to 5 hours. Next, the coating composition of the present invention will be described. The coating composition of the present invention contains the above-mentioned organic-inorganic composite resin as a binder, and further adjusts the solid content of the composition, if necessary, to preferably about 10 to 50% by weight. Organic solvents and fillers for improving the storage stability and coating workability of the composition, dyes,
Further, it is composed of a mixture of various additives such as a curing accelerator, a moisture scavenger, a thickener, and a pigment dispersant. Examples of the organic solvent include alcohols such as methanol, ethanol, propanol and butanol, ethylene glycol monoethyl ether, alcohol ethers such as ethylene glycol monobutyl ether,
A hydrophilic organic solvent such as ketones such as acetone and methyl ethyl ketone, and a mixed organic solvent thereof with a hydrophobic organic solvent for various coatings such as toluene, xylene, ethyl acetate and butyl acetate can be used. These organic solvents can be blended as a solvent so that the reaction occurs uniformly in the above-mentioned steps (I) and (II).

Examples of the filler include talc, barium carbonate, calcium carbonate, barium carbonate, bentonite,
Various extenders and coloring pigments for paints, such as titanium oxide, carbon black, red iron, and lithopone, 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. Are listed. These curing accelerators are desirably added in order to cure the coating composition faster at a relatively low temperature, and the amount thereof is, for example, 0.01 to 15 parts by weight per 100 parts by weight of the binder. It is.

The moisture scavenger is used in order to prevent a hydrolysis and condensation reaction in the presence of moisture and to increase the viscosity of the coating composition. Examples of the water scavenger include orthopropionate, orthoformate, and orthoacetate, and the amount thereof is, for example, based on 100 parts by weight of the binder.
0.5 to 20 parts by weight is suitable. The coating composition of the present invention is applied to the surface of the object to be coated by a coating means such as brush, spray, roll, dipping, and the like.
By baking at a temperature of 00 ° C. or less, a cured coating film can be formed. In addition, as an object to be coated, an inorganic ceramic substrate, various metal substrates such as stainless steel and aluminum, a glass substrate, a plastic substrate, and a paper substrate can be applied to various objects to be coated.

[0022]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, "parts" and "%" are shown on a weight basis unless otherwise specified. <Preparation of Silyl Group-Containing Vinyl Resin Solution (A)> 55 parts of xylene and 40 parts of isobutanol were added to a reactor equipped with a reflux condenser and a stirrer, mixed, and heated to 85 ° C. with stirring. . 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 resulting silyl group-containing vinyl resin solution (a) has a solid content of 50%.
The number average molecular weight was 10,000, 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%)
After mixing a solution consisting of 23 parts, 8 parts of methyltrimethoxysilane and 1.7 parts of dimethyldimethoxysilane, and a solution consisting of (b) 16 parts of a silyl group-containing vinyl resin solution (a) and 10 parts of isopropanol, Ion exchange water 3
Parts (equivalent to 0.72 equivalents per equivalent of hydrolyzable functional group)
And 0.1N hydrochloric acid so that the pH becomes 5.
For 3 hours. In the obtained reaction product, 65% of the hydrolyzable functional groups had undergone a hydrolytic condensation reaction (measured by gas chromatography). Next, 0.3 parts of triethoxyborane and 2.
After adding 5 parts and further reacting at 60 ° C. for 3 hours, 32 parts of isopropanol was added, and the mixture was cooled to room temperature and solid content of 3 parts.
2% of the coating composition was obtained.

Example 2 In a reactor equipped with a reflux condenser and a stirrer, (a) a partially hydrolyzed condensate of methyltrimethoxysilane (DC3074 manufactured by Dow Corning Toray Industries; solid content: 100%)
A solution consisting of 22 parts and 10 parts of methyltrimethoxysilane, and (b) a silyl group-containing vinyl resin solution (a) 16
And a solution consisting of 10 parts of isopropanol and 2.2 parts of ion-exchanged water (equivalent to 0.53 equivalent to 1 equivalent of hydrolyzable functional group) and 0.1 N hydrochloric acid to pH 5. And reacted at 60 ° C. for 3 hours. In the obtained reaction product, 50% of the hydrolyzable functional groups had undergone a hydrolytic condensation reaction. Next, 0.3 parts of triethoxyborane and 2 parts of ion-exchanged water were added to the reaction product, and the mixture was further reacted at 60 ° C. for 3 hours.
0 parts and ethyl orthopropionate 2 parts were added and cooled to room temperature to obtain a coating composition having a solid content of 32%.

Example 3 In a reactor equipped with a reflux condenser and a stirrer, (a)
A solution composed of 23 parts of SR2402 manufactured by Dow Corning Co., Ltd., 8 parts of methyltrimethoxysilane and 3 parts of dimethyldimethoxysilane, and (b) a vinyl resin solution containing a silyl group [Kanekazem, manufactured by Kanekachi Chemical Industry Co., Ltd.] Rack (50% solid content)], and a solution consisting of 20 parts and 15 parts of sopropanol. After mixing, 3 parts of ion-exchanged water and 1N hydrochloric acid are added to adjust the pH to 5, and the mixture is reacted at 60 ° C. for 3 hours. I let it. The obtained reaction product has 6 hydrolyzable functional groups.
5% had a hydrolytic condensation reaction. Next, 0.3 parts of triethoxyborane and 2.4 parts of ion-exchanged water were added to the obtained reaction product, and further reacted at 60 ° C. for 3 hours. Then, 20 parts of isopropanol and ethyl orthopropionate were added. 3 parts were added and cooled to room temperature to obtain a coating composition having a solid content of 35%.

Example 4 In a reactor equipped with a reflux condenser and a stirrer, (a) a solution consisting of 30 parts of methyltrimethoxysilane and 10 parts of dimethyldimethoxysilane, and (b) Kanegafuchi Chemical Industry Co., Ltd.
, Kanekazemurak 16 parts and isopropanol 10
5.4 parts of ion-exchanged water (corresponding to 0.72 equivalent relative to 1 equivalent of hydrolyzable functional group) and 1N hydrochloric acid so that the pH becomes 5. 60
The reaction was carried out at 3 ° C. for 3 hours. In the obtained reaction product, 68% of the hydrolyzable functional groups had undergone a hydrolytic condensation reaction. Next, 0.3 parts of triethoxyborane and 4 parts of ion-exchanged water were added to the reaction product, and after further reacting at 60 ° C. for 3 hours, 25 parts of isopropanol and 3 parts of ethyl orthopropionate were added. Cool to room temperature, solids 32
% Of the coating composition was obtained.

Comparative Example 1 In a reactor equipped with a reflux condenser and a stirrer, (a) a solution consisting of 30 parts of methyltrimethoxysilane and 10 parts of dimethyldimethoxysilane, and (b) Kanegafuchi Chemical Industry Co., Ltd.
, Kanekazemurak 16 parts and isopropanol 10
5.4 parts of ion-exchanged water and 1N hydrochloric acid so as to have a pH of 5, and further mixed with 60 parts of a solution.
The reaction was carried out at 3 ° C. for 3 hours. In the obtained reaction product, 68% of the hydrolyzable functional groups had undergone a hydrolytic condensation reaction. Next, 0.2 parts of diisopropylaluminum ethyl acetoacetate and 0.3 parts of ion-exchanged water were added to the reaction product, and after further reacting at 60 ° C. for 3 hours, 27 parts of isopropanol and 3 parts of acetylacetone were added. After cooling to room temperature, a coating composition having a solid content of 32% was obtained.

The coating compositions obtained in Examples 1 to 4 and Comparative Example 1 were subjected to various tests for the corrosiveness and the hardness, hot water resistance, stain resistance, and weather resistance of the resulting coating films. The results are shown in Table 1.

The test was performed according to the following method. <Corrosion test> After the coating composition was left in an iron container for one week, the color of the composition was observed. <Coating film performance test> A gypsum slag perlite plate (12 mm thick) was used as a material, and a polyisocyanate prepolymer solution sealer "V-Seran # 100 Sealer" (trade name, manufactured by Dainippon Paint Co., Ltd.) (butyl acetate) : 100% dilution with a 1: 1 solution of xylene).
The composition was spray-coated so as to be と 100 g / m ² (wet weight). This was dried at 100 ° C. for 5 minutes. Next, as a base paint, an acrylic silicone resin paint "V-Seran # 500 enamel" (trade name, manufactured by Dainippon Paint Co., Ltd.)
(40% dilution with a 1: 1 solution of butyl acetate: xylene)
Was spray-coated so that the coating amount was 80 to 90 g / m ² (wet weight). This was dried at 120 ° C. for 15 minutes. Next, a coating composition obtained by adding 3 parts of dibutyltin dilaurate to 100 parts by weight of each of the above-mentioned coating compositions was spray-coated so that the coating amount was (130 ± 10) g / m ² (wet weight). This was dried at 120 ° C. for 15 minutes and then at room temperature for 3 days. Hardness: Pencil hardness measured according to JIS K5400 Hot water resistance: The test piece was immersed in tap water at 60 ° C. for 7 days, and the abnormality of the appearance of the coating film was visually determined. ○ ・ ・ ・ No change △ ・ ・ ・ Slight change such as gloss reduction, whitening etc. × ・ ・ ・ Large change such as gloss reduction, whitening etc. Stain resistance: Decontamination property of red and black magic ink after 24 hours ◎・ ・ ・ Complete removal ○ ・ ・ ・ Very slight contamination △ ・ ・ ・ Contamination × ・ ・ ・ Remarkable contamination Weather resistance: Sunshine Weather-O-Meter 3000
Time ・ ・ ・: no change in the appearance of the coating film, gloss retention of 95% or more ・ ・ ・: slight change in the appearance of the coating, gloss retention of 80 to
94% ×: The coating film change is remarkable, the gloss retention is less than 80%

As is clear from Table 1, Example 1 of the present invention
The coating composition of ~ 4 does not corrode the iron container,
In addition, it had excellent coating performance. On the other hand, the coating composition of Comparative Example 1 using the metal chelate compound was:
When stored in an iron container, the composition turned red and was found to be red rust which corroded the container.

[0031]

[Table 1] Example 1 Comparative Example 1 2 3 4 1 No corrosiveness No abnormality Same as left Same as left Same as left Red color Hardness 3H> 3H Same as left Same as left Same as left Hot water resistance ○ ○ ○ ○ ○ Stain resistance ○ ◎ ◎ ◎ ◎ Weather resistance ○ ○ ○ ○ ○

[0032]

According to the present invention, an organic-inorganic composite resin can be produced without using a metal chelate compound and a chelating agent, and the coating composition using the organic-inorganic composite resin as a binder is stored in a metal container. However, the resulting coating film is excellent in weather resistance, stain resistance, hot water resistance and the like without corroding the container.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI C08L 85/04 C08L 85/04 C09D 183/10 C09D 183/10 185/04 185/04 (56) References JP-A-9-09 208830 (JP, A) JP-A-10-195381 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 77/442 C08G 77/20 C08G 77/398 C08G 79/08 C08L 83/10 C08L 85/04 C09D 183/10 C09D 183/04 C09D 185/04

Claims (1)

(57) [Claims] 1. A (I) (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
It is. (B) 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 100 parts by weight of the organosilane and / or a partially hydrolyzed condensate thereof. Of a hydrolyzable functional group in the mixture of 200 parts by weight
A step of performing a hydrolysis-condensation reaction so that 5 to 80% is reacted, and then (II) a total of the reaction product obtained in the step (I) and the components (a) and (b) remaining unreacted. Formula (2), B (OR ³ ) ₃ [wherein R ³ is an alkyl group having 1 to 4 carbon atoms, based on 100 parts by weight. Adding 0.001 to 3 parts by weight of a trialkoxyborane represented by the formula (1) and subjecting it to a hydrolysis-condensation reaction.