JP2000080324A - Resin composition for coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve storage stability, low temperature curability, adhesion, appearance, weatherability and resistances to chemicals and solvent by incorporating a specific acrylic resin, an organoalkoxysilane compound having a glycidyl group and a hydrolyzable alkoxysilane group, and an aluminium chelate compound. SOLUTION: A hydroxyl group-containing unsaturated monomer, a polymerizable carboxylic acid of formula I or II, and optionally, an unsaturated monomer having a hydrolyzable alkoxysilane group are copolymerized to obtain an acrylic resin having a hydroxyl value of 0.1 to 100 mg-KOH/g, an acid value of 0.5 to 50 mg-KOH/g, and a weight average molecular weight of 5,000 to 200,000. Then, 0.05 to 100 pt.wt. of an organoalkoxysilane compound having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule and 0.01 to 10 pt.wt. of an aluminium chelate compound are compounded in 100 pt.wt. of the acrylic resin. In the formula I, R represents H or CH3, and (n) is 1 to 4, and in the formula II, R represents H or CH3 and (n) is 1 to 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating resin composition having excellent curability at a low temperature of 80 ° C. or lower.

[0002]

2. Description of the Related Art Conventionally, a one-pack type coating resin excellent in curability at a low temperature of 80 ° C. or less has been demanded, and although the following techniques have been proposed, storage stability and curability have been proposed. However, none of the paints have the performance required for many paints in a well-balanced manner.

That is, in the case of a conventionally used curing system of an acrylic polyol having a hydroxyl group in a molecular side chain and a melamine resin or a blocked isocyanate, or an epoxy resin using a latent catalyst (curing agent), 120 ° C.
Curing at the curing temperature lower than this is not enough to obtain a sufficient cross-linking density, and the film performance cannot be expected. For curing at a temperature lower than that, multi-partization is necessary, and many problems remain in workability. In addition, when the polyisocyanate is used, the curability is good, but the toxicity of the isocyanate cannot be ignored.

As a relatively recent technology, there is a technology in which an alkoxysilane group or an epoxy group is disposed on an acrylic resin side chain and an aluminum chelate compound is added thereto (Japanese Patent Publication No. Sho 55-41712, Japanese Patent Publication No. Sho 60-50223). JP, JP-B-60-50225, JP-B-61-2
No. 3816, JP-B-61-23817, JP-A-64-75502, JP-A-4-139281, JP-A-1-259907, JP-A-1-28
No. 7177), this system has difficulty in arranging an alkoxysilane group on the side chain, and has poor storage stability.
This system is 2% for low temperature curing below 80 ° C in the general market.
It is applied as a liquid type.
Curability at low temperature of 0 ° C. or less is insufficient.

[0005] Further, because of having an alkoxysilane group, seeding (aggregation and the like) with a pigment is easily caused.
In addition, only the surface of the coating film is dried and hardened preferentially when applied (therefore, the solvent remains indefinitely inside the coating film, and the expected coating performance cannot be obtained). In some cases, there was a problem that spots were generated on the coating film surface.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a storage medium having a good storage stability at 80.degree.
It is an object of the present invention to provide a coating composition having excellent curability at a low temperature as described below, particularly a one-pack type oil composition for a coating, and to provide various properties required for a coating resin (adhesion, appearance, weather resistance). Another object of the present invention is to provide a resin composition for coatings, which is well balanced in chemical resistance, solvent resistance and the like.

[0007]

That is, the present invention provides an acrylic resin (A) obtained by copolymerizing a hydroxyl group-containing unsaturated monomer and a polymerizable carboxylic acid represented by the following formula I or II as essential components. A) an organoalkoxysilane compound (B) having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule per 100 parts by weight;
00 parts by weight, and an aluminum chelate compound (C)
It is a resin composition for coatings comprising 0.01 to 10 parts by weight.

[0008]

Embedded image (However, R represents H or CH ₃ , and n represents an integer of 1 to 4.)

Embedded image (Wherein, R represents H or CH _3, n is an integer of 1 to 10.)

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The acrylic resin (A) used in the present invention is obtained by copolymerizing a hydroxyl group-containing unsaturated monomer and the polymerizable carboxylic acid represented by the above formula I or II as essential copolymerization components. Can be obtained.

Examples of the hydroxyl group-containing unsaturated monomer include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and acrylic acid. 4-hydroxybutyl, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monoacrylate, polypropylene glycol monomethacrylate, polybutylene glycol monoacrylate, polybutylene glycol monomethacrylate, etc.
Species or two or more can be used.

These hydroxyl group-containing unsaturated monomers are preferably copolymerized so that the hydroxyl value of the acrylic resin (A) is 0.1 to 100 mgKOH. The hydroxyl value is 0.
If it is less than 1, the expected solvent resistance may not be obtained. If it exceeds 100, the viscosity of the composition becomes high, and the storage stability of the composition deteriorates. The form may not be maintained. However, when used as a two-pack type, 100 mg
It is also possible to exceed KOH, which is preferred because the curability is improved.

Specific examples of the polymerizable carboxylic acid represented by the formula I or II include an acrylate of hydroxypropionic acid and a succinate of 2-hydroxyethyl (meth) acrylate. These polymerizable carboxylic acids may be used alone or in combination of two or more. Further, ordinary α, β-unsaturated carboxylic acids such as acrylic acid and methacrylic acid may be used in combination. The acrylic resin (A) obtained by copolymerizing these polymerizable carboxylic acids improves curability and appearance of a coating film. In order to obtain sufficient curability, storage stability, and coating film performance, the acid value of the acrylic resin (A) is 0.5 to 50 mg.
It is preferred to copolymerize to KOH. If the acid value is less than 0.5, sufficient curability may not be obtained, and if it exceeds 50, the storage stability of the composition deteriorates, and
In some cases, the form as a liquid type composition cannot be maintained. However, when used as a two-pack type, it is possible to exceed 50 mg KOH, and this is preferred because the curability is improved.

In preparing the acrylic resin (A) of the present invention, the above-mentioned unsaturated monomer having a hydroxyl group or a monomer copolymerizable with the polymerizable carboxylic acid represented by the formula I or II is appropriately added. In addition, they can be copolymerized. Examples of such a monomer include styrene and (meth) acrylates. Examples of the (meth) acrylate include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, i-butyl methacrylate, cyclohexyl methacrylate, and 2-ethylhexyl methacrylate. , Lauryl methacrylate, stearyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, t-acrylate
-Butyl, i-butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate and the like. The monomers may be used alone or as a mixture of two or more. Further, if necessary, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-acryloyloxypropyl Unsaturated monomers having a hydrolyzable alkoxysilane group such as trimethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, 3-acryloyloxypropyltriethoxysilane, 3-acryloyloxypropylmethyldiethoxysilane,
Chain transfer agent having a hydrolyzable alkoxysilane group such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldiethoxysilane (polymerization degree regulator ) Can also be copolymerized. These monomers may be used alone or as a mixture of two or more.

The use of a chain transfer agent such as 3-mercaptopropyltrimethoxysilane makes the composition highly solid (reduction of the amount of solvent discharged during coating, that is, low pollution and resource saving), and appearance of the coating film ( It is an effective means for improving gloss and leveling properties (smoothness and sharpness of a coating film). In particular, it is effective as a top coat for paints for plastics. For this purpose, the chain transfer agent is preferably used in an amount of 0.05 to 50 parts by weight based on 100 parts by weight of the hydroxyl group-containing unsaturated monomer. If the amount is less than 0.05 parts by weight, it is difficult to achieve the desired high solidification,
If it exceeds 0 parts by weight, it is difficult to increase the polymerization rate during the production of the acrylic resin (A), and unreacted monomers tend to remain.

The acrylic resin (A) is preferably a graft copolymer obtained by copolymerizing an alkyl (meth) acrylate-based macromonomer in an amount of 0.5 to 10% by weight based on all copolymerized components. This improves the leveling properties of the paint (smoothness, glossiness, sharpness, concealment of scratches on the substrate after drying), surface drying (skinning; applying the paint to the substrate, drying and curing) In this case, it refers to a phenomenon in which only the surface of the coating film is dried and cured preferentially and wrinkles are generated on the surface of the coating film. This phenomenon is remarkable when applied in a state of high humidity (70% or more), which is extremely effective in preventing the problem.

The poly (alkyl meth) acrylate macromonomer referred to herein is a homopolymer such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, or the like. An acryloyl group at the terminal of the polymer main chain of a copolymer, or a homopolymer or copolymer such as methyl acrylate, ethyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, or , Methacryloyl group.

The poly (alkyl methacrylate) macromonomer has a weight average molecular weight of 2 as measured by the method described below.
It is preferably from 000 to 100,000. If the molecular weight is less than 2,000, sufficient effects for improving leveling property and preventing surface drying may not be obtained.
If it exceeds 0000, the viscosity of the composition tends to increase and the gloss of the coating film tends to decrease.

When a polyalkyl (meth) acrylate macromonomer is used, it is preferably used in an amount of 0.5 to 10% by weight based on all monomers to be copolymerized. 0.5
If the amount is less than 10% by weight, the expected effect cannot be obtained.
If it exceeds, turbidity may occur in the coating film. Also, 1
When the content exceeds 0% by weight, for example, when used as a base coat, a metal swim (when a metallic paint is applied and a top coat is applied thereon), the metal (aluminum pigment) as a pigment moves, and (Phenomenon such as deterioration or irregular reflection of light such as irregular reflection of light) or bleeding (when the base coat is attacked by the solvent of the top coat and the color (pigment) of the base coat is the top coat) Bleeding) and color separation (for similar reasons, the color of the coating film differs from the designed coating color)
Easily occur.

Although the preferred molecular weight of the acrylic resin depends on the application, the weight average molecular weight of the acrylic resin measured by GPC in terms of standard polystyrene is 500.
It is preferably from 0 to 200,000. Those having a small molecular weight are suitable for use in automotive plastics as high solid and high appearance types, and those having a large molecular weight are suitable for use in high quality building material coatings. However, when the molecular weight is too small, the curability tends to deteriorate, and when the molecular weight is too large, the storage stability tends to deteriorate.

The acrylic resin is produced as a solvent solution or an aqueous dispersion by ordinary radical copolymerization. In the case of the present invention, toluene, xylene, butyl acetate, ethyl acetate, isopropyl alcohol, n-butyl alcohol,
Using an organic solvent such as ethylene glycol monobutyl ether, α, α′-azobisisobutyronitrile, α, α
An organic azo polymerization initiator such as' -azobis valeronitrile, and an organic peroxide such as benzoyl peroxide and t-butylperoxy-2-ethylhexanoate are used as polymerization initiators, and the polymerization temperature is 40 to 150. It is preferably produced by solution polymerization of the hydroxyl group-containing unsaturated monomer, polymerizable carboxylic acid and other copolymerizable monomers at a temperature of ° C.

The acrylic resin (A) has a carboxyl group and a hydroxyl group at the side chain or at the terminal of the polymer. Thereby, the solvent resistance of the cured coating film (solvent rubbing property (resistance of the coating film to the solvent when the coating film is rubbed with a solvent)), gasohol property (gasoline / methyl alcohol = 1 /
1 (volume ratio) of the coating film when dipped in a solution) and the like. Therefore, if a paint using the composition of the present invention is used, lifting (coating is eroded by solvent and swells and shrinks) at the time of touch-up (repainting to correct the defect of the paint defect portion). It does not wake up and improves workability. Also, for the same reason, lifting does not occur during recoating (repainting of defective parts or painting on old paint film), adhesion, paint film appearance,
The coating film performance such as weather resistance is excellent.

Examples of the organoalkoxysilane compound (B) having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule include γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropyltriethoxy. Silane, γ-glycidoxypropyltriisopropoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyldimethoxysilane, and the like. These compounds can be used alone or It may be a mixture of two or more. Further, partial condensates of these compounds may be used.

Organoalkoxysilane compound (B)
Is 0.05 with respect to 100 parts by weight of the acrylic resin (A).
-100 parts by weight, whereby a paint having excellent properties such as curability, storage stability and weather resistance can be obtained. 0.05
If the amount is less than 100 parts by weight, the curability is reduced. If the amount exceeds 100 parts by weight, only the surface of the coating is dried and hardened quickly, and the appearance of the coating film is deteriorated.

The aluminum chelate compound (C) of the present invention includes aluminum ethyl acetoacetate diisopropylate, aluminum tris (ethyl acetoacetate), aluminum tris (acetyl acetate), aluminum bisethyl acetoacetate monoacetylacetonate and the like. These may be used alone or as a mixture of two or more. The compound is
The curable resin composition of the present application functions as a starter for curing.

In order to suppress the catalytic action of the aluminum chelate during storage and to improve the storage stability of the paint, keto-enol tautomers can be used. Compounds that can be keto-enol tautomers include, specifically, β-dikenes such as acetylacetone, acetoacetates such as methyl acetoacetate, malonic esters such as ethyl malonate, β Examples thereof include aldehydes having a hydroxyl group at the -position and esters having a hydroxyl group at the -position such as methyl salicylate.
Among these, it is more preferable to use acetoacetic esters and β-diketones.

The aluminum chelate compound (C) is used in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the acrylic resin (A).
Use parts by weight. If the amount is less than 0.01 part by weight, the curability of the coating material deteriorates, the crosslinking is delayed, and the solvent resistance and weather resistance of the coating film are reduced. If it exceeds 10 parts by weight, it will not be able to be sufficiently dissolved in the acrylic resin, and conversely, the curability will be deteriorated, and there will be bumps on the coating film, and the appearance of the coating film will deteriorate.

The resin composition for coatings of the present invention may further contain an epoxy resin (D). The main purpose of this is to obtain a coating composition particularly suitable for metals which are easily corroded, but the substrate to be coated is not necessarily limited to metals.

The epoxy resin can be arbitrarily selected and used from many commercially available ones. That is, these include a polyphenol type, a polyglycidylamine type, an alcohol type, an ester type, an alicyclic type, and others (reference: 13197, a chemical product, Kagaku Kogyo Nippo, published in 1997, P923-P931). These epoxy resins (D) may be used alone or as a mixture of two or more. The epoxy equivalent of the epoxy resin (D) is from 100 to 2,000 in order to obtain sufficient curability, storage stability and coating film performance. If the epoxy equivalent is less than 100, the coating film becomes hard and brittle, and if it exceeds 2,000, sufficient curability and corrosion resistance cannot be obtained.

The epoxy resin (D) is a resin composition 1 for paint.
5 to 50 parts by weight are blended with respect to 00 parts by weight. If the amount is less than 5 parts by weight, sufficient corrosion resistance cannot be obtained. If the amount exceeds 50 parts by weight, the curability deteriorates, and cracks (cracking of the coating film, undercoating, and overcoating) occur in tests such as weather resistance. Peeling) easily occurs.

The resin composition for coatings of the present invention can be prepared by various methods, but simply, an aluminum chelate compound (C) is charged little by little while stirring the acrylic resin (A) and dissolved. Next, the organoalkoxysilane compound (B) is added, and stirring is continued until the mixture becomes uniform. Heating may be used if necessary during this manufacturing process, but sufficient manufacturing is possible at room temperature, and stability of the manufacturing (because the curing reaction proceeds during the manufacturing and no gel is formed), storage From the viewpoint of stability, 20
It is preferably manufactured at ５０50 ° C.

Furthermore, by adding a diluent containing a hydrophilic organic solvent to the composition and stirring and mixing until the composition becomes uniform, the curability at low temperatures can be further improved.

Another effective method is to produce the organoalkoxysilane compound (B) as described below, and then blend it with other raw materials to similarly improve the curability at low temperatures.

That is, a predetermined amount of the organoalkoxysilane compound (B) is measured in a container equipped with a stirrer, and while stirring, a diluting solution containing a hydrophilic organic solvent is added to dilute the organoalkoxysilane compound (B). This is a method of preparing a liquid in advance.

The term "hydrophilic organic solvent" as used herein refers to an organic solvent which is soluble in water at 20 ° C. in a volume ratio of 10% or more, such as alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, and n-butyl alcohol; Examples include glycol ethers such as glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol butyl ether. These solvents may be used alone or as a mixture of two or more.

By blending a diluent containing a hydrophilic organic solvent, the curability and storage stability of the composition are improved, and the finished appearance (leveling property, Sharpness, gloss, etc.) are improved. The diluting solution containing a hydrophilic organic solvent is preferably used in an amount of 100 parts by weight or less based on 100 parts by weight of the organoalkoxysilane compound (B) in order to prevent only drying of the surface of the paint.

Further, the diluting solution is 100% by weight or less of water based on 100 parts by weight of the hydrophilic organic solvent (the pH at 25 ° C. is preferably 6.8 in order to improve the storage stability of the composition).
By containing the following ion-exchanged water, the curability at low temperatures is further improved.

The composition of the present invention can be used as it is or as a paint, that is, if necessary, a pigment such as titanium dioxide, carbon black or aluminum paste, or a well-known paint additive (leveling). Agents, pigment dispersants, anti-settling agents, UV absorbers, light stabilizers (HAL
S), an antifoaming agent, etc.) and a solvent for dilution, and then used as a base coat (undercoat) or a topcoat (overcoat). Further, other paints such as acrylic urethane resin paint, urethane resin paint, alkyd resin paint, epoxy resin paint, fluororesin paint, silicone resin paint, acrylic silicone resin paint, etc. (Reference: 13197 Chemical Products, Chemical Daily Inc.) (1
997))). That is, to give an example, it is also possible to apply a paint prepared using the composition of the present application as a base coat and then use an acrylic urethane resin paint as a top coat.

Base materials that can be coated include plastics such as ABS, polystyrene, polycarbonate, and nylon;
Metals such as iron, aluminum, galvanized iron and tin; and
These include those subjected to chemical conversion treatment, those subjected to cationic or anionic electrodeposition coating, and building materials such as mortar, cement, asbestos cement, asbestos cement perlite, bricks, tiles, and slate.

The coating method used is a coating prepared using the composition of the present invention, such as spray coating, brush coating, roller coating, coating with a roll coater, curtain coating, anionic electrodeposition coating, and cationic electrodeposition coating. The methods commonly used in the industry can be applied.

Painted articles can be used in a wide variety of industries. That is, for example, plastic parts and metal materials of automobiles and motorcycles (from small to large), plastic parts and metal members of household appliances,
There are outer wall materials (sizing boards, curtain walls, aluminum sashes), roof tiles, and the like.

Hereinafter, the present invention will be described in detail with reference to embodiments.

Unless otherwise specified, parts are by weight and composition ratios are by weight.

[0043]

Example 1 Methyl methacrylate solution-polymerized using α, α′-azobisisobutyronitrile as a polymerization initiator and a polymerization temperature of 90 ° C. using toluene / isobutanol (= 60/40) as a solvent. (MMA) / n-butyl methacrylate (BM
A) / n-butyl acrylate (BA) / methacrylic acid 2
-Hydroxyethyl (HEMA) / acrylate of hydroxypropionic acid (β-CEA) (= 40/2)
4/20/10/6) of an acrylic copolymer (= 50% solid content, weight average molecular weight 35,000, acid value 23) was charged in a stainless beaker equipped with a stirrer (1000 g). Chelate AW (aluminum chelate compound (aluminum tris (acetylacetate)); product of Kawaken Fine Chemical Co., Ltd.) 10
g and stir until homogeneously dissolved (about 10 minutes).

To this was added 200 g of a diluting solution of the organoalkoxysilane compound (= SH-6040 / isopropyl alcohol / ion-exchanged water (= 90/9/1)) which had been previously mixed to form a uniform solution, Then, the mixture was stirred and mixed to obtain a coating resin composition of Example 1.

Example 2 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / β-CEA / AA-6 (macromonomer (polymethyl methacrylate macromonomer); a product of Toagosei Co., Ltd.) (= 40 / 28.8 / 20/10 / 0.2 / 1)
(= Solid content 50%, weight average molecular weight 35,000, acid value 0.
8) and Epicoat # 828 (bisphenol A type epoxy resin; manufactured by Ciba Geigy)
A coating resin composition of Example 2 was obtained in the same manner as in Example 1 except that 0 g and 30 g of acetylacetone were added.

Example 3 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / β-CEA / AA-6 (macromonomer (polymethyl methacrylate macromonomer); product of Toagosei Co., Ltd.) (= 40/20/17/10/12/1) (= 50% solids, A coating resin composition of Example 3 was obtained in the same manner as in Example 2, except that the weight average molecular weight was 35,000 and the acid value was 47).

Example 4 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / β-CEA / methacrylic acid (MAA) / AA-6
(Macromonomer (polymethyl methacrylate macromonomer); product of Toagosei Co., Ltd.) (= 40/24/20)
/ 10/3/2/1) (= solid content 50%, weight average molecular weight 35,000, acid value 25) except that the coating resin composition of Example 4 was prepared in the same manner as in Example 2. Obtained.

Example 5 MMA prepared by solution polymerization using α, α'-azobisisobutyronitrile as a polymerization initiator at a polymerization temperature of 80 ° C. and toluene / isobutanol (= 60/40) as a solvent.
BMA / BA / HEMA / β-CEA / AA-6 (= 4
Example 2 except that 0/23/20/10/6/1) (= solid content 50%, weight average molecular weight 80,000, acid value 23).
In the same manner as in the above, a coating resin composition of Example 5 was obtained.

Example 6 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / β-CEA / AA-6 (= 40/23/20/10
/ 6/1) (= 50% solids, 3.5 weight average molecular weight)
Example 6 in the same manner as in Example 2, except that the acid value was 23) and the amount of the aluminum chelate AW was 0.5 g.
Was obtained.

Example 7 A coating resin composition of Example 7 was obtained in the same manner as in Example 6, except that the addition amount of the aluminum chelate AW was changed to 50 g.

Example 8 An aluminum chelate AW was added in an amount of 10 g, and a diluting solution of an organoalkoxysilane compound (= SH-6040 / isopropyl alcohol / ion-exchanged water (= 90/9) was previously mixed to form a uniform solution. A coating resin composition of Example 8 was obtained in the same manner as in Example 6, except that the amount of (1/1)) was changed to 5 g.

Example 9 A dilution of an organoalkoxysilane compound (= SH-6040 / isopropyl alcohol / ion-exchanged water (= 90/9) was prepared by adding an aluminum chelate AW to 10 g, mixing in advance, and forming a uniform solution. A coating resin composition of Example 9 was obtained in the same manner as in Example 6, except that the amount of (1 /)) was changed to 500 g.

Comparative Example 1 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / AA-6 (= 40/29/20/10/1) (= solid content: 50%, weight average molecular weight: 35,000) Except for using the resin for the coating material of Comparative Example 1 in the same manner as in Example 2. A composition was obtained.

Comparative Example 2 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / MAA / AA-6 (= 40/25/20/10/4)
/ 1) (= solid content 50%, weight average molecular weight 35,000, acid value 26) except that a resin composition for coating of Comparative Example 2 was obtained in the same manner as in Example 2.

Comparative Example 3 The acrylic copolymer composition was changed to MMA / BMA / BA / β-C
Comparative Example 3 in the same manner as in Example 2 except that EA / AA-6 (= 40/33/20/6/1) (= solid content: 50%, weight average molecular weight: 35,000, acid value: 23) Was obtained.

Comparative Example 4 The acrylic copolymer composition was changed to MMA / BMA / BA / HEM.
A / β-CEA / AA-6 (= 40/23/20/10
/ 6/1) (= 50% solids, 3.5 weight average molecular weight)
, Acid value 23) and the addition amount of aluminum chelate AW is 0.
A resin composition for a paint of Comparative Example 4 was obtained in the same manner as in Example 2 except that the amount was changed to g. Comparative Example 5 A dilution of an organoalkoxysilane compound (= SH-6040 / isopropyl alcohol / ion-exchanged water (= 90/9/1)) in which the addition amount of the aluminum chelate AW was 10 g, and the mixture was mixed in advance to form a uniform solution. ) Was obtained in the same manner as in Comparative Example 4 except that the addition amount was 0 g.

Using the compositions obtained in Examples and Comparative Examples, tests and evaluations as coatings were performed. Table 1 shows the results. The evaluation method is as follows.

(1) Solvent resistance ABS obtained by defatting the composition with isopropanol (IPA)
It was applied to a plate and dried by heating at 80 ° C for 30 minutes. The coated surface was rubbed 20 times with a felt impregnated with toluene (TOL), and the degree of attack of the coating film by the solvent was determined. ○ Good solvent resistance with no abnormalities. (Pass) × Part or all of the coating film is dissolved in the solvent. (failure)

(2) Gel fraction The composition was applied to a polypropylene plate and dried by heating at 80 ° C for 30 minutes. The coating film was peeled off from the polypropylene plate, and the solvent insoluble matter (gel fraction) was measured using a Soxhlet extractor using acetone / methanol (50/50 vol%) as a solvent. The higher the gel fraction (the larger the numerical value), the better the crosslinkability. Pass if 70% or more.

(3) Internal curability The composition was applied to an IPA-degreased ABS plate using a 20 mil applicator, and the dried and cured state of the coating film was examined. ○ The film is cured uniformly to the inside of the coating film, and the surface condition is good. △ The surface hardens slightly, but the appearance is good. (Passed or more) × Only the surface is dried and cured preferentially, and wrinkles are generated on the coating film surface. (failure)

(4) Corrosion Protection The composition was applied to a degreased polished steel plate so that the coating thickness became 50 μm, and a salt spray test was carried out according to JIS K 5400 for 500 hours. ○ Good without any abnormality (pass) △ Rust is observed on the cut part (pass) × Rust is observed on the entire coated surface (fail)

(5) Storage stability About 80 ml of the composition was placed in a 100 ml glass bottle, sealed, and allowed to stand at 40 ° C. for one month. One month later, the state of the composition was visually determined. ○ Good without aggregation, thickening, sedimentation, separation, etc. (Pass) △ Thickening, sedimentation, separation (pass) less than twice as much as before test × Thickening, sedimentation, separation (not good) more than twice as much as before test Passed)

[0063]

[Table 1]

[0064]

The resin composition for coating of the present invention is formed into a coating by a usual coating preparation method, then applied to various substrates and dried at room temperature, or dried by heating to obtain adhesion, A coating film excellent in many coating performances such as weather resistance, chemical resistance, and solvent resistance can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (reference) // C08F 220/28 C08F 220/28 290/06 290/06 F term (reference) 4J027 AA01 AB10 AB25 AB28 AC02 AC03 AC04 AC06 AJ02 BA02 BA05 BA07 BA08 BA10 BA12 CB03 CB09 CC02 CD08 4J038 CG141 CH121 CH151 CJ031 CJ101 CJ181 DB002 DL052 GA03 GA06 HA156 JA19 JA25 JA34 JC38 KA03 KA04 KA06 NA26 PA19 4J100 AB02AL05P08 AL05R08P08 CA04 CA05 JA01

Claims (4)

[Claims] An unsaturated monomer having a hydroxyl group and a compound represented by the following formula I:
Or an organoalkoxysilane having a glycidyl group and a hydrolyzable alkoxysilane group in one molecule per 100 parts by weight of an acrylic resin (A) obtained by copolymerizing a polymerizable carboxylic acid represented by the formula II as an essential component A coating resin composition comprising 0.05 to 100 parts by weight of the compound (B) and 0.01 to 10 parts by weight of the aluminum chelate compound (C). Embedded image (However, R represents H or CH ₃ , and n represents an integer of 1 to 4.) (Wherein, R represents H or CH _3, n is an integer of 1 to 10.) 2. The method according to claim 1, wherein the acrylic resin (A) is a graft copolymer obtained by copolymerizing a polyalkyl (meth) acrylate-based macromonomer in an amount of 0.5 to 10% by weight based on all copolymerized components. Paint resin composition. 3. An epoxy equivalent of 10 parts by weight based on 100 parts by weight of the coating resin composition according to claim 1 or 2.
A resin composition for coatings, further comprising 5 to 50 parts by weight of 0 to 2000 epoxy resin (D). 4. The method according to claim 1, wherein 0.1 to 20.0 parts by weight of acetylacetone and / or diacetyl alcohol are further added to 1 part by weight of the aluminum chelate compound (C). A resin composition for a paint according to the above item.