JP2000319582A - Resin composition for coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition having improved weather resistance, curable at a normal temperature, suitable for a coating material without impairing excellent adhesivity and corrosion resistance which an epoxy resin-based coating film has. SOLUTION: This resin composition for a coating material of epoxysiloxane base useful for a coating material composition is obtained by heating (A) 30-99 wt.% of an epoxy resin component which is an epoxy resin component containing one or more epoxy groups in one molecule in which >=10 wt.% of an epoxy resin in the epoxy resin component contains one or more hydroxy groups in one molecule and (B) 1-70 wt.% of an organopolysiloxane containing an alkoxysilyl group and subjecting them to a dealcoholization condensation reaction. The coating material composition comprises an amino group-containing compound selected from an aliphatic or alicyclic amine adduct, an aliphatic or alicyclic Mannich compound, an aliphatic or alicyclic ketimine and amino group-containing silane coupling agent in an amount to make 0.4 to 1.5 equivalent active hydrogen of amino group based on 1 equivalent of epoxy group of the resin composition for a coating material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition, and more particularly, to a coating composition which is excellent in compatibility, gloss and adhesion, is effective for cosmetic and protection to metals and the like, and can be cured at room temperature. The present invention relates to an epoxysiloxane-based coating resin composition used for a product.

[0002]

2. Description of the Related Art For large structures such as ships, bridges, tanks, etc., there is a demand for a room temperature curable resin composition having both protection and beauty. Conventionally, for the purpose of protection, as a room temperature curable epoxy resin composition, a composition comprising an epoxy resin represented by polyglycidyl ether and a cured product such as polyamine, polyamidoamine and the like is widely known from the viewpoint of adhesion and corrosion resistance. However, there is a problem that the weather resistance is poor. On the other hand, for the purpose of cosmetics, room-temperature-curable polyurethane resin compositions, acrylic silicone resin compositions, and fluororesin compositions having excellent weather resistance have been applied, but these are inferior in adhesion and corrosion resistance. However, it cannot be applied directly to a steel sheet, but is usually applied on a primer coating such as an epoxy resin coating, which has a problem in the coating process. Also,
JP-T-10-509195 discloses a mixture of an epoxy resin, a polysiloxane, a low-molecular-weight organosiloxane having an alkoxysilyl group, and a difunctional amine. Is insufficient, the corrosion resistance and weather resistance are not sufficient, the gloss of the coating film is low, and the protection and the cosmetics have not been satisfied.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional cold-curable composition, to provide excellent adhesion, corrosion prevention and adhesion to a steel sheet, and to provide both protection and cosmetic functions. It is an object of the present invention to provide a room temperature curable composition.

[0004]

The present inventors have conducted various studies to solve the above problems, and as a result, have found that a hydroxyl group contained in an epoxy resin and an organopolysiloxane having a specific alkoxysilyl group are subjected to a dealcoholization condensation reaction. It was found that by using the resin composition bonded and bonded, a room temperature curable composition capable of forming a coating film having excellent adhesion, gloss, corrosion resistance, and weather resistance was obtained, and to complete the present invention. Reached.

[0005] Thus, the present invention relates to (A) one molecule per molecule.
An epoxy resin component having at least one epoxy group, wherein at least 10% by weight of the epoxy resin component is a resin having at least one hydroxyl group in one molecule; % And (B) 1 to 70% by weight of an organopolysiloxane containing an alkoxyl group directly bonded to a silicon atom ((A) + (B) =
(100% by weight) and subjecting it to a dealcoholization condensation reaction to provide a resin composition.

The present invention also relates to an aliphatic or alicyclic amine adduct, an aliphatic or alicyclic Mannich compound, an aliphatic or alicyclic ketimine, with respect to one equivalent of the epoxy group of the resin composition. And a curable composition containing an amino group-containing compound selected from amino group-containing silane coupling agents in an amount such that the active hydrogen of the amino group is 0.4 to 1.5 equivalents. It is.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the resin composition of the present invention will be described in detail.

The resin composition of the present invention is obtained by heating the following epoxy resin component (A) and the following organopolysiloxane (B) to cause a dealcoholization reaction.

Epoxy resin component (A) The epoxy resin component (A) comprises an epoxy resin having one or more, preferably two or more epoxy groups in one molecule. The epoxy resin having a weight percentage of at least one is a resin having one or more hydroxyl groups in one molecule. The epoxy resin component (A) has an epoxy equivalent in the range of 150 to 1000, and more preferably 170 to 500 from the viewpoint of reactivity with the organopolysiloxane (B) and curability due to reaction with the curing agent. preferable.

The epoxy resin component (A) may be composed of one kind of epoxy resin or a mixture of two or more kinds of epoxy resins.

The epoxy resin component (A) is appropriately selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, alkyl ether type epoxy resin, hydrogenated bisphenol A type epoxy resin and the like. can do. Among these, bisphenol A type epoxy resin and hydrogenated bisphenol A type epoxy resin are preferable from the viewpoint of the anticorrosion property of the obtained coating film.

Organopolysiloxane (B) Organopolysiloxane (B) is an organopolysiloxane containing an alkoxyl group directly bonded to a silicon atom, and has the following formula: R ¹ _a (R ² O) _b SiO _{(4 -ab) / 2} (wherein, R ¹ is the same or different and represents an alkyl group or an aryl group having 1 to 8 carbon atoms, R ² represents an alkyl group having 1 to 8 carbon atoms, and a is 1.0 ≦ a ≦ 2.0, b is 0.1
≦ b ≦ 1.5) can be preferably used.

In the above formula, specific examples of the alkyl group having 1 to 8 carbon atoms for R ¹ include a methyl group, an ethyl group, a propyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group and a cyclopentyl group. , A cyclohexyl group and the like, and specific examples of the aryl group for R ¹ include a phenyl group and a tolyl group. As R ¹ , among these, a methyl group, an ethyl group, a propyl group, and a phenyl group are preferable in terms of availability, reactivity, and the like.

Specific examples of the alkyl group having 1 to 8 carbon atoms as R ² include a methyl group, an ethyl group, a propyl group, a pentyl group, a hexyl group, a heptyl group and an octyl group. Of these, a methyl group and an ethyl group are preferred from the viewpoint of reactivity.

In the above formula, a is 1.0 ≦ a ≦ 2.0
And b is within the range of 0.1 ≦ b ≦ 1.5, which indicates the reactivity with the hydroxyl group in the epoxy resin component (A), the physical properties of the obtained coating film, the curability, and the weather resistance. It is suitable in terms of properties and the like.

The organopolysiloxane (B) has a content of an alkoxyl group directly bonded to a silicon atom in the organopolysiloxane (B) of 5 to 45% by weight, preferably 7 to 40% by weight, more preferably 10 to 40% by weight. It is preferable that the content is within the range of 35% by weight in view of reactivity with the hydroxyl group in the epoxy resin component (A), physical properties, curability, weather resistance and the like of the obtained coating film. In the R ¹ group of the above formula, it is preferable that the aryl group is 65 mol% or less from the viewpoint of weather resistance. The organopolysiloxane (B) has a weight average molecular weight in terms of polystyrene of 300 to 300.
It is desirable from the viewpoint of physical properties, curability and the like of a coating film using the obtained resin composition to be within the range of 30,000.

Commercially available organopolysiloxanes (B) include, for example, DC3074, DC3037, SR2
402 (all products manufactured by Toray Dow Corning Co., Ltd.); KR9218, X-40-9220 (all products manufactured by Shin-Etsu Chemical Co., Ltd.), TSR165, XR-31
B1763 (both are products of Toshiba Silicone Co., Ltd.) and the like.

The organopolysiloxane (B) may be one or a mixture of two or more alkoxypolysiloxane-containing organopolysiloxanes, such as the above-mentioned commercially available products, and the partial hydrolysis / condensation of the one or two or more mixtures. And a partially hydrolyzed / condensed product of an alkoxyl group-containing organopolysiloxane and an organo or trialkoxy silane. Examples of the diorganodialkoxysilane include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and methylphenyldimethoxysilane.Examples of the organotrialkoxysilane include methyltrimethoxysilane. Examples thereof include methyltriethoxysilane, methyltriisopropoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane. It is preferable that the organopolysiloxane (B) does not contain a silanol group or has a low silanol group content. In the case of obtaining any of the above-mentioned partial hydrolysis and condensation products, the partial hydrolysis and condensation
It is preferable to employ reaction conditions in which silanol groups hardly remain, but if the silanol group content is small even if silanol groups are generated in the partial hydrolysis / condensation reaction,
It is possible to use as organopolysiloxane (B).

The resin composition of the present invention is obtained by heating the epoxy resin component (A) and the organopolysiloxane (B) in the presence of a reaction catalyst, if necessary, to carry out a dealcoholization condensation reaction. Obtainable.

Epoxy resin component (A) in the above reaction
And the organopolysiloxane (B) in a compounding ratio of
With respect to the total amount of (A) and (B), it is preferable from the viewpoint of the curability and weather resistance of the obtained resin composition to be within the following range.

Epoxy resin component (A): 30 to 99% by weight, preferably 60 to 95% by weight; organopolysiloxane (B): 1 to 70% by weight, preferably 5 to 40% by weight. As a reaction catalyst in the above reaction, a metal alkoxide compound, a metal chelate compound, a metal ester compound and the like are used. Examples of the metal alkoxide compound include aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide, and aluminum tri-n-.
Butoxide, aluminum triisobutoxide, aluminum tri-sec-butoxide, aluminum tri-te
aluminum alkoxides such as rt-butoxide; tetramethyl titanate, tetraethyl titanate, tetra-
titanium alkoxides such as n-propyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate, tetraisobutyl titanate, tetra-tert-butyl titanate, tetra-n-hexyl titanate, tetraisooctyl titanate, tetra-n-lauryl titanate; Tetraethyl zirconate, tetra-n
-Propyl zirconate, tetraisopropyl zirconate, tetra-n-butyl zirconate, tetra-sec
-Butyl zirconate, tetra-tert-butyl zirconate, tetra-n-pentyl zirconate, tetra-te
zirconium alkoxides such as rt-pentyl zirconate, tetra-tert-hexyl zirconate, tetra-n-heptyl zirconate, tetra-n-octyl zirconate, tetra-n-stearyl zirconate; dibutyltin dibutoxide; As the metal chelate compound, for example, tris (ethyl acetoacetate)
Aluminum, tris (n-propylacetoacetate) aluminum, tris (isopropylacetoacetate) aluminum, tris (n-butylacetoacetate) aluminum, isopropoxybis (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, tris ( Proponylacetonate)
Aluminum, diisopropoxypropionylacetonatoaluminum, acetylacetonatobis (propionylacetonato) aluminum, monoethylacetoacetatebis (acetylacetonato) aluminum, acetylacetonatoaluminum disec-butyrate,
Methyl acetoacetate aluminum di-tert-butylate, bis (acetylacetonato) aluminum mono
sec Aluminum chelate compounds such as butyrate and di (methylacetoacetate) aluminum mono-tert-butylate; diisopropoxy bis (ethylacetoacetate) titanate, diisopropoxy bis (acetylacetonato) titanate, di-n-butoxy. Titanium chelate compounds such as bis (acetylacetonato) titanate; tetrakis (acetylacetonato) zirconium, tetrakis (n-propylacetoacetate)
Zirconium, tetrakis (ethyl acetoacetate)
Zirconium chelate compounds such as zirconium; dibutyltin bis (acetylacetonate); and metal ester compounds, for example, dibutyltin diacetate, dibutyltin di (2-ethylhexylate), dibenzyltin di (2-ethylhexylate) ),
Examples include tin ester compounds such as dibutyltin dilaurate and dibutyltin diisooctyl maleate.

These reaction catalysts can be used alone or in combination of two or more. The reaction catalyst is a component that is used as needed to promote the reaction between the epoxy resin component (A) and the organopolysiloxane (B). When used, the reaction catalyst includes (A) and (B). A total of 100
0.001 to 5 parts by weight with respect to parts by weight, preferably
The use of 0.005 to 1 part by weight is appropriate from the viewpoint of the effect of accelerating the reaction and the anticorrosion of the cured product using the obtained resin composition.

The reaction temperature and reaction time in the reaction between the epoxy resin component (A) and the organopolysiloxane (B) are not particularly limited as long as the temperature and time at which the dealcoholization condensation reaction proceeds. However, usually, the reaction temperature is 60 to 250 ° C, preferably 80 ° C to 20 ° C.
0 ° C, more preferably in the range of 100 to 160 ° C, and the reaction time is 0.5 to 24 hours, preferably 1 to 12 hours.
Preferably, it is within a time range. In the above reaction, the reaction time can be shortened by removing the alcohol generated by the reaction from the system.

In the above reaction, it is sufficient that the dealcoholization condensation reaction is performed until the obtained resin can exhibit the performance as a coating resin. Even if some of the hydroxyl groups are reacted, substantially all of the hydroxyl groups are reacted. It may be reacting. The degree of progress of the reaction can be known by a method of determining the absorption intensity due to the hydroxyl group by infrared absorption spectrum (IR) measurement or a method of measuring the amount of alcohol generated by the reaction.

The curable composition of the present invention can be obtained by combining the thus obtained resin composition of the present invention with the following amino group-containing compound (C) as a curing agent.

Amino group-containing compound (C) The amino group-containing compound (C) used in the curable composition of the present invention is a product of a dealcoholization condensation reaction between the epoxy resin component (A) and the organopolysiloxane (B). A curing agent that reacts with an epoxy group in the resin composition, acts as a reaction catalyst when an alkoxyl group in the resin composition and water in the air cause a hydrolysis / condensation reaction, and the resin composition of the present invention It contributes to the curing of the product.

The amino group-containing compound (C) has an amino group, and when combined with the resin composition of the present invention, can cure the resin composition, Any material can be used without particular limitation as long as it can form a cured product such as a coating film having excellent compatibility and excellent in gloss, adhesion, aesthetics, and protection of a substrate such as a metal. Examples of the amino group-containing compound (C) include aliphatic or alicyclic amine adducts, aliphatic or alicyclic Mannich compounds, and aliphatic or alicyclic ketimines (aliphatic and alicyclic amine adduct ketimines are also included). ) And at least one selected from amino group-containing silane coupling agents can be suitably used.

Examples of the aliphatic or alicyclic amine adduct include diethylenetriamine, triethylenetetraamine, tetraethylenepentamine, diethylaminopropylamine, metaxylenediamine, mensendiamine, isophoronediamine, and 1,3-bisamine. Aminomethylcyclohexane, aliphatic or alicyclic amines such as menthanediamine and bisphenol A diglycidyl ether, propylene glycol diglycidyl ether,
Examples include various glycidyl-type epoxy compounds such as phenylglycidyl ether and adducts with alkylene oxides such as ethylene oxide and propylene oxide.

The above-mentioned aliphatic or alicyclic Mannich compound is obtained by reacting the aliphatic or alicyclic amine used in the production of the above-mentioned aliphatic or alicyclic amine adduct with a phenol or formaldehyde. Mannich compounds can be mentioned.

The aliphatic or alicyclic ketimines include aliphatic or alicyclic amines used in the production of the aliphatic or alicyclic amine adducts and the aliphatic or alicyclic amine adducts. Ketimine compounds with ketone compounds can be mentioned.

The above-mentioned aliphatic or alicyclic amine adduct,
Commercial products of the aliphatic or alicyclic Mannich compound and the aliphatic or alicyclic ketimine include, specifically, for example, "Sunmide I518" manufactured by Sanwa Chemical Industry Co., Ltd.
"Sunmide J230N";"DitoclarB1969" manufactured by Daito Sangyo Co., Ltd., and the like.

The amino group-containing silane coupling agent includes, for example, N-β- (aminoethyl) γ-
Aminopropyltrimethoxysilane, N-β- (aminoethyl) γ-aminopropylmethyldimethoxysilane,
γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane and the like can be mentioned.

The above-mentioned amino group-containing compounds can be used alone or in combination of two or more.

In the curable composition of the present invention, the resin composition, which is a product of a dealcoholization condensation reaction of an epoxy resin component (A) and an organopolysiloxane (B), is combined with the amino group-containing compound (C). The compounding ratio is such that the ratio of the number of equivalents of active hydrogen of amino groups in (C) / the number of equivalents of epoxy groups in the resin composition falls within the range of 0.4 to 1.5. It is suitable from the viewpoints of curability, weather resistance and the like of the obtained curable composition.

The curable composition of the present invention may contain, if necessary, a coloring pigment such as iron oxide or titanium oxide, or a curing catalyst such as a tin compound in addition to the resin composition and the amino group-containing compound (C). And other additives may be included.

When the curable composition of the present invention is applied, the coating method is not particularly limited. For example, brush coating, air spray coating, airless spray coating, roll coater, flow coater The coating can be carried out by using the method described above, and the thickness of the applied film is not particularly limited, but is usually preferably in the range of 10 to 120 μm. The curable composition of the present invention can be cured at room temperature, and the cured product exhibits excellent performance, but may be subjected to forced drying or heat curing. The curable composition of the present invention is applied to a metal such as a steel sheet to provide excellent corrosion resistance,
Although it is possible to obtain weather resistance and the like, it can be usefully applied to other cement-based structures, inorganic cured products, and the like.

[0037]

EXAMPLES The present invention will be specifically described below with reference to examples. Hereinafter, “parts” and “%” indicate “parts by weight” and “% by weight”, respectively, unless otherwise specified.

Production Example 1 Production example of methoxy group-containing organopolysiloxane (a) "DC3074" (manufactured by Toray Dow Corning, methoxy group-containing silicone) was placed in a reaction vessel equipped with a thermometer, a thermostat, a stirrer, and a reflux condenser. Resin, phenyl group content about 49%, methoxy group content about 17%, weight average molecular weight about 1,400) 100 parts, isopropyl alcohol 20
Parts, 0.2 parts of diisopropoxyacetylacetotitanium,
After charging 1.0 part of deionized water and stirring at 80 ° C. for 1 hour,
Replace the reflux condenser with a solvent distilling tube, blow nitrogen gas,
While removing the solvent, the mixture was stirred at 130 ° C. for 10 hours to obtain a methoxy group-containing organopolysiloxane (a). This had a phenyl group content of about 49%, a methoxy group content of about 14%, and a weight average molecular weight of about 12,000.

Production Example 2 Production Example of Organopolysiloxane Containing Methoxy Group (b) 100 parts of "DC3074", 10 parts of methyl alcohol, and 10 parts of diisopropoxy were placed in a reaction vessel equipped with a thermometer, thermostat, stirrer and reflux condenser. 0.2 parts of acetylacetotitanium and 4.5 parts of deionized water were charged, and reflux temperature (7
After reacting for 1 hour at 6 ° C.), 100 parts of “SR2402” (manufactured by Toray Dow Corning Co., Ltd., methoxy group-containing silicone resin, phenyl group content 0%, methoxy group content 34%) was charged, and the reflux condenser was subjected to solvent distillation. The mixture was stirred at 120 ° C. for 6 hours while removing the solvent instead of the outlet tube to obtain a methoxy group-containing organopolysiloxane (b). This had a phenyl group content of about 20%, a methoxy group content of about 19%, and a weight average molecular weight of about 8,200.

Example 1 Production Example of Resin Composition (A) In a reaction vessel equipped with a thermometer, a thermostat, a stirrer, and a distilling tube, "Epicoat 828" (manufactured by Yuka Shell Epoxy, bisphenol A type epoxy resin) , Epoxy equivalent about 185) 75 parts, "DC3074" (manufactured by Dow Corning Toray Co., Ltd., methoxy group-containing silicone resin, phenyl group content about 49%, methoxy group content about 17%, weight average molecular weight about 1,400) 25 Parts, 20 parts of xylene, and 0.1 part of tetraisopropoxytitanium were charged, heated to 135 ° C., and then stirred for 4 hours while blowing nitrogen gas to remove the solvent, thereby producing a resin composition (A). . From the result of infrared absorption spectrum (IR) measurement, it was confirmed that this product contained almost no hydroxyl group.

Example 2 Production Example of Resin Composition (B) "Epicoat 834" (manufactured by Yuka Shell Epoxy Co., Ltd., bisphenol A type epoxy resin) was placed in a reaction vessel equipped with a thermometer, a thermostat, a stirrer, and a distillation tube. , Epoxy equivalent 2
50) 60 parts, “DC3074” 40 parts, xylene 40
Parts, and 0.1 part of tetraisopropoxy titanium.
After heating to 35 ° C., stirring was continued for 6 hours while blowing nitrogen gas to remove the solvent, thereby producing a resin composition (B). From the result of infrared absorption spectrum (IR) measurement, it was confirmed that this product contained almost no hydroxyl group.

Example 3 Production Example of Resin Composition (C) 25 parts of “Epicoat 828” and “Epicoat 1” were placed in a reaction vessel equipped with a thermometer, a thermostat, a stirrer, and a cooler.
001 "(Bisphenol A, manufactured by Yuka Shell Epoxy)
Epoxy resin, epoxy equivalent about 475) 25 parts, "X
R-31-B1763 "(manufactured by Toshiba Silicone Co., Ltd., methoxy group-containing organopolysiloxane, methoxy group content 3
0%, the content of the aryl group in R ¹ in the above formula is 30 mol%, and the weight average molecular weight is about 5,000) 50
Part, xylene 40 parts, tetraisopropoxytitanium 0.1 part.
Two parts were charged, heated to 150 ° C., and continued to be stirred for 12 hours to produce a resin composition (C). It was confirmed from the infrared absorption spectrum (IR) measurement results that the amount of hydroxyl groups had decreased.

Examples 4 to 8 Production Examples of Resin Compositions (DH) Except that the type and amount of epoxy resin and the type and amount of methoxy group-containing organopolysiloxane were changed as shown in Table 1 below, In the same manner as in Example 1, resin compositions (D to H) were obtained.

[0044]

[Table 1]

(Note) in the above Table 1 has the following meanings. (* 1) ST-3000: manufactured by Toto Kasei Co., Ltd., trade name,
Hydrogenated bisphenol A type epoxy resin, epoxy equivalent 2
30. (* 2) X-40-9220: manufactured by Shin-Etsu Chemical Co., Ltd.
The brand name, methoxy group-containing organopolysiloxane, and the methoxy group content in the polysiloxane are 30%, the weight average molecular weight is about 900, and the aryl group is not contained in the polysiloxane.

Examples 9 to 16 and Comparative Examples 1 to 3 Each of the curable compositions was obtained by mixing the components shown in Table 2 below. This composition was applied on a steel plate degreased with acetone by spray coating so as to have a dry film thickness of about 70 μm, dried at room temperature (about 20 ° C.) for 2 weeks, and then subjected to a test.
Each of the curable compositions was dried on a glass plate to a dry film thickness of about 40 μm.
m and dried for one day, and the compatibility was evaluated. The test results are shown in Table 2 below.

The above test was performed according to the following test method.

Test Method Compatibility: The transparency of the film applied to the glass plate was evaluated according to the following criteria. ：: transparent, ×: cloudy.

Initial gloss: The gloss of the film applied to the glass plate was visually evaluated. ：: Matted ×: Matted letter.

Anticorrosion: After a salt spray test was conducted for 100 hours in accordance with JIS K5400.9.1, the state of the coating film was observed and evaluated according to the following criteria. ：: No abnormality △: Slight rust ×: Notable rust

Weather resistance: JIS K5400.9.8.1
After performing an accelerated weathering test with a sunshine weatherometer specified in (1) for 500 hours, the glossiness of the coating film was visually compared with the initial coating film (an accelerated weathering test was not performed). ：: Little change Δ: Slight decrease ×: Significant decrease.

[0052]

[Table 2]

(Note) in the above Table 2 has the following meanings. (* 3) Daitoclar B1969: Daito Sangyo Co., Ltd.
Manufactured, alicyclic amine adduct, active hydrogen equivalent 95. (* 4) Sunmide J230N: manufactured by Sanwa Chemical Co., Ltd., polyoxyethylenediamine, active hydrogen equivalent 87.

As apparent from Table 2 above, Examples 9 to
All 16 curable compositions are excellent in compatibility, and the resulting coating film is excellent in gloss, corrosion resistance, and weather resistance. As described above, the curable composition of the present invention has excellent compatibility, because the epoxy resin and the alkoxyl group-containing organopolysiloxane are chemically bonded, gives a good coating appearance, and has excellent weather resistance and corrosion resistance. An excellent film can be formed.

[0055]

The curable composition of the present invention has excellent adhesion and anticorrosion properties of an epoxy resin-based coating film,
It has improved weather resistance, which is its drawback, and can be cured at room temperature, and its coating film has excellent adhesion to steel plates and the like, corrosion resistance and weather resistance, and therefore has a very high practical value.

Continuation of the front page F term (reference) 4J038 DB031 DB041 DB061 DB071 DL031 DL051 GA02 GA03 GA07 GA15 JB01 JB08 JB09 JB18 JC35 KA03 KA04 LA02 MA14 NA01 NA03 NA12 PA18 PC02

Claims (6)

[Claims] (A) An epoxy resin component having one or more epoxy groups in one molecule, and 10% by weight or more of the epoxy resin component in the epoxy resin component has one hydroxyl group in one molecule. (B) an organopolysiloxane containing an alkoxyl group directly bonded to a silicon atom (30 to 99% by weight).
A resin composition for a coating, wherein 0% by weight (provided that (A) + (B) = 100% by weight) is heated to cause a dealcoholization condensation reaction. 2. The method according to claim 2, wherein the epoxy resin component (A) is 150
The epoxy resin having an epoxy equivalent in the range of ~ 1,000 and at least 60% by weight of the epoxy resin component (A) contains at least one hydroxyl group in one molecule. Item 4. The resin composition according to Item 1. 3. The epoxy resin component (A) is at least one selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, alkyl ether type epoxy resin and hydrogenated bisphenol A type epoxy resin. The resin composition according to claim 1 or 2, which is a kind of epoxy resin. 4. The method according to claim 1, wherein the organopolysiloxane (B) is
Following rational formula _{^{R 1 a (R 2 O)}} b SiO in _{(4-ab) / 2 (wherein,} R ¹ are the same or different, represent an alkyl group or an aryl group having 1 to 8 carbon atoms, R ² is Represents an alkyl group having 1 to 8 carbon atoms, a is 1.0 ≦ a ≦ 2.0, b is 0.1
≤ b ≤ 1.5)
And a 5 to 45% by weight based on the alkoxyl group content of organopolysiloxane (B), the amount of the aryl group of R ¹ is not more than 65 mol%, yet polystyrene equivalent weight average molecular weight from 300 to 30 The resin composition according to any one of claims 1 to 3, which is in a range of 3,000. 5. The reaction according to claim 1, wherein the dealcoholization condensation reaction is carried out in the presence of 0.001 to 5 parts by weight of a reaction catalyst based on 100 parts by weight of the total of the epoxy resin component (A) and the organopolysiloxane (B). The resin composition according to any one of claims 1 to 4, wherein the reaction is performed at a reaction temperature of ~ 250 ° C. 6. An aliphatic or alicyclic amine adduct per 1 equivalent of an epoxy group of the resin composition according to claim 1,
An aliphatic or alicyclic Mannich compound, an amino group-containing compound selected from an aliphatic or alicyclic ketimine and an amino group-containing silane coupling agent, wherein the active hydrogen of the amino group is 0.4 to 1.5 equivalents. A coating composition characterized in that it contains the following amount.