JPH09227643A - Resin composition and its cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition which can give coating films having excellent adhesion to metals and good surface hardness by mixing an epoxy (meth)acrylate obtained by a specified reaction with a diluent. SOLUTION: This composition is obtained by mixing an epoxy (meth)acrylate resin (A) comprising a reaction product of a compound (a) having at least two epoxy groups in the molecule with an unsaturated monoarboxylic acid (b) and a benzothiazole compound (c) represented by formula I (wherein (n) is 1-5) (e.g. a compound represented by formula II) with a diluent. It can be cured by irradiation with electron beams or ultraviolet rays. When it is to be cured by irradiation with ultraviolet rays, it is desirable to add a photopolymerization initiator to the system. The composition can give coating films having excellent adhesion to metals and good surface smoothness and is therefor suitable as varnishes, coating materials, ink vehicler, coating agents, and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition which is cured by irradiation with radiation such as ultraviolet rays and electron beams, and more particularly to a resin composition which is useful as a coating agent or paint for metals and its cured product. .

[0002]

2. Description of the Related Art Conventionally, as an ultraviolet curable resin,
Unsaturated group-containing resins are widely used, but when metals such as aluminum, iron, copper, gold, silver or alloys are used as the base material, they have the drawback of being difficult to adhere.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a resin composition having excellent adhesion to metals and its cured product.

That is, the present invention is represented by a compound (a) having at least two epoxy groups in the molecule, an unsaturated group-containing monocarboxylic acid (b) and a general formula (1). Reaction product with the benzothiazole compound (c).

[0004]

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(In the formula, n is an integer of 1 to 5.) The present invention relates to a resin composition containing an epoxy (meth) acrylate resin (A) and a diluent (B) and a cured product thereof.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the compound (a) having at least two epoxy groups in the molecule, the unsaturated group-containing monocarboxylic acid (b) and the benzoic acid represented by the general formula (1) are used. An epoxy (meth) acrylate resin (A) which is a reaction product with a thiazole compound (c) is used. Said,
The epoxy (meth) acrylate resin (A) includes a compound (a) having at least two epoxy groups in the molecule, an unsaturated group-containing monocarboxylic acid (b), and the above general formula (1).
The benzothiazole compound (c) represented by can be reacted.

Specific examples of the compound (a) having at least two epoxy groups in the molecule include, for example, bisphenol type diglycidyl ether compounds such as bisphenol A, bisphenol F and bisphenol S, or diglycidyl ethers thereof. And a polymer of the above bisphenol, a bisphenol type polyglycidyl ether compound obtained by reacting epichlorohydrin with an alcoholic hydroxyl group of the above bisphenol type diglycidyl ether polymer, a reaction condensate of the above bisphenol type diglycidyl ether compound and formalin, Phenol novolac type epoxy resin, cresol novolac type epoxy resin,
Trisphenol methane type epoxy resin, triglycidyl ether isocyanurate, fatty polyglycidyl ether (eg, trimethylolpropane triglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, polyethylene glycol diglycidyl ether, etc.), alicyclic epoxy Resin (eg, 3,4-epoxycyclohexylmethyl-3,4-
Epoxy cyclohexyl carboxylate, bis (3,
4-epoxycyclohexylmethyl) adipate, etc.),
Glycidyl (meth) acrylate and glycidyl (meth)
Compounds having one unsaturated group in the molecule other than acrylate (for example, acrylic acid, methacrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth)
Acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
Styrene, α-methylstyrene, polyethylene glycol mono (meth) acrylate, glycerin mono (meth)
Copolymers with acrylates).

Specific examples of the unsaturated group-containing monocarboxylic acid (b) include (meth) acrylic acid, unsaturated group-containing monohydroxy compounds (eg, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl ( (Meth) acrylate, 1,4-butanediol mono (meth) acrylate, pentaerythritol tri (meth)
Acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, etc. and a dibasic acid anhydride (for example, succinic anhydride, maleic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride). Half ester etc. which are reaction products of acid etc.) can be mentioned.

Specific examples of the benzothiazole compound (c) represented by the general formula (1) include, for example,

[0010]

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[0011]

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[0012]

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The above can be mentioned. It is preferable to react 0.5 to 1.5 equivalents of carboxylic acid in the total amount of component (b) + component (c) with respect to 1 equivalent of epoxy group in component (a), particularly preferably 0.8 to 1.2 equivalents.
The ratio of the components (b) and (c) used is 50
To 99 mol% and component (c) 1 to 50 mol% are preferable,
Particularly preferably, the component (b) is 70 to 95 mol% and the component (c) is 5 to 30 mol%. As a diluent during the reaction, for example, methyl ethyl ketone, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, toluene, cyclohexane, solvent such as solvent naphtha, or carbitol (meth) acrylate, Phenoxyethyl (meth) acrylate, acryloylmorpholine,
Pentaerythritol tetra (meth) acrylate, trimethylolpropane tri (meth) acrylate, nonanediol di (meth) acrylate, tris (hydroxyethyl) isocyanurate tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol It is preferred to use reactive monomers such as poly (meth) acrylate.

Further, it is preferable to use a catalyst (eg, triethylamine, benzyldimethylamine, methyltriethylammonium chloride, triphenylstibine, triphenylphosphine, etc.) in order to accelerate the reaction. It is preferably 0.1 to 10% by weight, particularly preferably 0.2 to 5% by weight, based on the raw material mixture.

In order to prevent the polymerization during the reaction, it is preferable to use a polymerization inhibitor (for example, methquinone, hydroquinone, methylhydroquinone, phenothiazine, etc.), and the amount thereof is preferably based on the reaction raw material mixture. 0.01 to 1% by weight, particularly preferably 0.05 to
0.5% by weight. The reaction temperature is preferably 60-15
The temperature is 0 ° C, particularly preferably 80 to 120 ° C. The reaction time is preferably 5 to 60 hours, particularly preferably 10 to
50 hours. In this way, the epoxy (meth) acrylate resin (A) can be obtained. Weight average molecular weight of epoxy (meth) acrylate resin (A) [GPC
(Measured by (gel permeation chromatography)] is usually 500
-50000, preferably 1000-30000.

The amount of the epoxy (meth) acrylate resin (A) contained in the composition of the present invention is 10 to 9 in the composition.
0 wt% is preferable, and 20 to 80 wt% is particularly preferable. The diluent (B) is used in the present invention. Diluent (B)
As specific examples of, for example, methyl ethyl ketone, methyl isobutyl ketone, ethyl cellosolve, carbitol, propylene glycol monomethyl ether, acetic acid ethyl ester, acetic acid butyl ester, ethyl cellosolve acetate, butyl cellosolve acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ester. Solvents such as ether acetate, toluene, cyclohexane, solvent naphtha, or hydroxyethyl (meth)
Acrylate, hydroxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, carbitol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, acryloylmorpholine, N-vinylcaprolactam, phenyloxyethyl (meth) Acrylate, phenylpolyethoxy (meth) acrylate, (meth) acrylamide, 3-phenyloxy-2-hydroxypropyl (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 2-ethyl-2-butyl-1. , 3-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate Relate, tripropylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, bisphenol A polyethoxydi (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane polyethoxytri (meth) acrylate, pentaerythritol Examples thereof include reactive monomers such as tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, and dipentaerythritol poly (meth) acrylate.

When the composition of the present invention is cured, it can be cured by irradiating it with an electron beam or ultraviolet rays, but when it is cured with ultraviolet rays, it is preferable to add a photopolymerization initiator.
Specific examples of the photopolymerization initiator include, for example, benzoin methyl ether, benzoin isopropyl ether, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-
[4- (methylthio) phenyl] -2-morpholino-
Propan-1-one, N, N-dimethylaminoacetophenone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2,4-dimethylthioxanthone,
2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, acetophenone dimethyl ketal, benzophenone, 4,4′-dichlorobenzophenone, 4,4′-bisdiethylaminobenzophenone, Michler's ketone and the like can be mentioned. These can be used alone or in combination of two or more.

Further, the photopolymerization initiator may be a known or commonly used photosensitizer such as N, N-dimethylaminobenzoic acid ethyl ester and N, N-dimethylaminobenzoic acid isoamyl ester, or two or more of them may be used. It can be used in combination.

The proportion of the photopolymerization initiator used is preferably 0 to 30 parts by weight in the composition of the present invention.

The composition of the present invention further comprises, if necessary, organic and inorganic pigments, extender pigments, plasticizers, defoamers, leveling agents, silane coupling agents, light stabilizers, antioxidants, polymers ( For example, acrylic polymer, urethane polymer, polybutadiene polymer, butadiene rubber modified epoxy), epoxy resins (for example, bisphenol A type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, etc.), epoxy curing agent, polymerization inhibitor Etc. can also be added.

The composition of the present invention is obtained by blending the blending components preferably in the above proportions and uniformly mixing them by heating, dissolving, mixing, kneading and the like. A cured product of the composition of the present invention can be obtained by a conventional method, preferably by irradiating with ultraviolet rays. That is, it can be cured with ultraviolet rays and, if necessary, with heat to obtain a cured product.

[0022]

EXAMPLES The present invention is described below with reference to examples, but the present invention is not limited to the following examples. In the examples, "parts" means "parts by weight". (Synthesis example of component (A)) Synthesis example 1 Phenol novolac type epoxy resin (Nippon Kayaku Co., Ltd.)
Made, EPPN-201, softening point 65 ° C, epoxy equivalent 2
00) 200 parts, acrylic acid 57.6 parts, benzothiazole compound of the following structural formula 45 parts

[0023]

[Chemical 6]

0.5 parts of methyl hydroquinone and 230 parts of propylene glycol monomethyl ether acetate were charged, heated to 90 ° C. and dissolved by stirring, and then cooled to 60 ° C. and 1.7 parts of triphenylphosphine were charged, 9
The reaction was carried out at 5 ℃ and the acid value of the reaction solution was 1.0 (mgKOH / g)
The reaction was terminated when the following (about 32 hours) was reached to obtain an epoxy acrylate resin (A-1). The weight average molecular weight (solid content only) of this product was about 12,000. The viscosity (25 ° C, poise) of the product (A-1) was 200 poise.

Synthesis Example 2 Cresol novolac type epoxy resin (Nippon Kayaku Co., Ltd.)
Manufactured by EOCN-104S, softening point 92 ° C, epoxy equivalent 220) 220 parts, acrylic acid 57.6 parts, benzothiazole compound 45 parts of the following structural formula

[0026]

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0.5 parts of methylhydroquinone and 245 parts of propylene glycol monomethyl ether acetate were charged, heated to 90 ° C., stirred and dissolved, then cooled to 60 ° C. and 1.7 parts of triphenylphosphine charged, 95 The reaction is carried out at ℃, the acid value of the reaction solution is 1.0
When it was below (mgKOH / g) (about 32 hours), the reaction was terminated to obtain an epoxy acrylate resin (A-2). The weight average molecular weight (solid content only) of this product was about 7,000. The viscosity of the product (A-2) (25 ° C, poise) is 1
It was 80 poise.

Synthetic Example 3 Synthetic Example of Epoxy (meth) acrylate Resin Not Containing Component (c)) Phenol novolac type epoxy resin (Nippon Kayaku Co., Ltd.)
Made, EPPN-201, softening point 65 ° C, epoxy equivalent 2
00) 200 parts, 72 parts of acrylic acid, 0.5 parts of methylhydroquinone, and 206.6 parts of propylene glycol monomethyl ether acetate are charged, heated to 90 ° C., stirred and dissolved, then cooled to 60 ° C., and triphenylphosphine is added. 1.4 parts were charged and the reaction was carried out at 95 ° C.
When the acid value of the reaction solution becomes 1.0 (mgKOH / g) or less (about 32 hours), the reaction is terminated and the epoxy acrylate resin (A
-O-1) was obtained. Viscosity of product (A-O-1) (25
C., poise) was 120 poise.

Examples 1 and 2 Comparative Example 1 A resin composition was blended according to the blending composition shown in Table 1 (numerical values are parts by weight), mixed and dissolved. This is thickness 300
It is applied by a roll coating method to a film thickness of 5 μm (dry film thickness) on a μm aluminum plate and a tiffle steel plate, dried at 80 ° C. for 5 minutes, and then a high pressure mercury lamp of 80 w / cm for 20 m It was passed at a speed of / min to cure the coating film. Table 1 shows the results of evaluating the adhesiveness and pencil hardness of the obtained coating film. The evaluation was performed as follows. (Adhesion): Based on JIS K5400
The number of 00 cells and the number of squares where the coating film did not peel off by the cellophane tape peeling test were displayed. (Pencil hardness): Based on JIS K5400, the pencil hardness was measured using a Mitsubishi pencil "Uni".

[0030]

Table 1 Example Comparative Example 1 2 1 Epoxy acrylate resin (A-1) 100 obtained in Synthesis Example 1 Epoxy acrylate resin (A-2) 100 obtained in Synthesis Example 2 100 Epoxy obtained in Synthesis Example 3 Acrylate resin (A-O-1) 100 KAYARAD MANDA * 1 10 KAYARAD R-561 * 2 20 10 20 Propylene glycol monomethyl ether atate 35 35 35 Irgacure 907 * 3 2.3 2.3 2.3 L-7604 (leveling agent) * 4 0.4 0.4 0.4 Adhesive Aluminum plate 100/100 100/100 30/100 Tin-free steel plate 100/100 100/100 20/100 Pencil hardness Aluminum plate 6H 5H F Tin-free steel plate 6H 5H F

Note) * 1 KAYARAD MAND
A: Nippon Kayaku Co., Ltd., hydroxypivalic acid neopentyl glycol diacrylate * 2 KAYARAD R-561: Nippon Kayaku Co., Ltd.
Phenoxyethyl acrylate * 3 Irgacure 907: Ciba-Geigy
Photopolymerization initiator, 2-methyl-1- [4- (methylthio)
Phenyl] -2-morpholino-propan-1-one * 4 L-7604: manufactured by Nippon Unica Co., Ltd., a leveling agent

As is clear from the results shown in Table 1, the resin composition of the present invention has excellent adhesion to metals and high hardness of the cured product.

[0033]

The coating film obtained by the resin composition of the present invention has excellent adhesion to metals and has a good surface hardness, and is suitable for varnish, paint, vehicle of ink, coating agent, etc. It is a thing.

Claims (2)

[Claims] 1. A compound (a) having at least two epoxy groups in a molecule and an unsaturated group-containing monocarboxylic acid (b).
And a benzothiazole compound (c) represented by the general formula (1). (In the formula, n is an integer of 1 to 5.) A resin composition containing an epoxy (meth) acrylate resin (A) and a diluent (B). 2. A cured product of the composition according to claim 1.