JPH05310891A - Epoxy resin composition and method for curing the same - Google Patents

Abstract

PURPOSE:To obtain a resin compsn. which gives a cured thin film excellent in heat resistance and is suitable for a powdered insulation coating material by compounding a polyepoxy resin with a maleimide compd., a curative, and a basic catalyst. CONSTITUTION:100 pts.wt. epoxy resin having at least two epoxy groups in the molecule (e.g. bisphenol A diglycidyl ether), 1-100 pts.wt. maleimide compd. (e.g. N-phenylmaleimide), 1-200 pts.wt. epoxy resin curative (e.g. triethylenetetramine), and 0.001-10 pts.wt. basic catalyst (e.g. triethanolamine) are compounded to give an epoxy resin compsn., which is formed into a 0.1-500mum-thick film and cured at 100-250 deg.C to give a heat-resistant thin film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin composition containing an epoxy compound which gives a cured product of a thin film having excellent heat resistance, and particularly to be used as a powder insulating coating material and a liquid insulating material. It is suitable for.

[0002]

2. Description of the Related Art With the demand for higher performance and higher reliability of electrical equipment, insulating materials for these electrical equipment are required to have chemical stability and physical reliability at high temperatures. became. Furthermore, with the improvement of the production cycle, it has become important to shorten the molding time. Epoxy resin, which has been widely used as an insulating resin for electric devices, has good workability and excellent adhesion to an insulating material, but has low heat resistance. Further, the curing reaction in the thin film state has a drawback that it is extremely slowed because internal heat storage is lost.

Various proposals have been made to improve the curability, but none of the proposals hitherto been satisfactory. For example, the method for accelerating the curing rate of an epoxy resin described in Japanese Patent Laid-Open No. 64-51442 uses a boron fluoride / amine complex, so that there is a problem that boron fluoride is generated and the metal is immersed during curing. .. Further, the fast-curing epoxy resin composition described in JP-A-1-144443 cures a hydroquinone type epoxy resin with dicyandiamide, but has a problem of toxicity of the resin used. A composition using a polyfunctional epoxy resin such as a bisphenol AD epoxy resin and an aromatic amine has also been proposed (JP-A-2-281068), but a thin film can be obtained by using the polyfunctional epoxy resin. Although the curing speed in the above method is slightly improved, the degree of the improvement is small.

[0004]

DISCLOSURE OF THE INVENTION The present invention is intended to provide an epoxy resin composition capable of giving a cured product having excellent curability in a thin film and excellent heat resistance, and a curing method using the same. To do.

[0005]

The present invention provides the following (A).
To provide an epoxy resin composition comprising a component, a component (B), a component (C) and a component (D),
In addition, the curing method of the present invention uses the composition having a film thickness of 0.1 to 50.
0 μm, cure at a curing temperature range of 100 to 250 ° C.,
It is intended to provide a method for obtaining a cured product having excellent heat resistance.

Component (A): Epoxy resin having at least two epoxy groups in one molecule (B) Component: Maleimide compound (C) Component: Curing agent for epoxy resin (D) Component: Basic catalyst

(Epoxy Resin) Examples of the epoxy resin having at least two epoxy groups in one molecule, which is the component (A) of the composition of the present invention, include the following (the following are all commercial products. Example by name).

Diglycidyl ether of bisphenol A; as its products, Epicoat 827, 828, 834, 1001 of Yuka Shell Epoxy Co., Ltd.
1004, 1007, 1009, Ciba's Araldite GY250, 6099, Union Carbide's ERL2774, Dow Chemical's DER332, 331, 661, etc.

Epoxyphenol novolac; as its products, Epicoat 152 and 154 of Yuka Shell Epoxy Co., Ltd., DEN438 and 448 of Dow Chemical Co., and Araldite EPN1138 and 11 of Ciba Co.
39 mag.

Epoxy cresol novolac; as its products, Arubaito ECN1235, 1273, 1280, etc. of Ciba.

Brominated epoxy resin; as its products, Epicoat 5050 manufactured by Yuka Shell Epoxy Co., Ltd., BREN manufactured by Nippon Kayaku Co., Ltd., etc.

In addition, glycidyl ester compounds obtained from diglycidyl ether of bisphenol F, phthalic acid, hexahydrophthalic acid or dimer acid and epichlorohydrin, epoxy resins obtained from aromatic amines such as aminophenol and diaminodiphenylmethane and epichlorohydrin, Examples thereof include cycloaliphatic epoxy resins obtained from dicyclopentadiene and the like and peracetic acid, 1,4-butanediol diglycidyl ether, and 1,6-hexanediol diglycidyl ether.

(Maleimide Compound) The maleimide compound as the component (B) in the present invention includes the following (i)
Examples of the compounds include (iii). (I) Monomaleimide compound N-phenylmaleimide, N- (2-methyl) maleimide, N- (2-chlorophenyl) maleimide, N- (4
-Hydroxyphenyl) maleimide, N- (4-carboxyphenyl) maleimide, N-cyclohexylmaleimide and the like.

(Ii) Bismaleimide compound N, N'-ethylene bismaleimide, N, N'-hexamethylene bismaleimide, N, N'-m-phenylene bismaleimide, N, N'-p-phenylene bismaleimide, N, N '-(4,4'-diphenylmethane) bismaleimide, N, N'-(4,4'-diphenylether) bismaleimide, N, N'-methylenebis (3-chloro-p-phenylene) bismaleimide, N, N'-
(4,4'-diphenyl sulfone) bismaleimide,
N, N '-(4,4'-dicyclohexylmethane) bismaleimide, N, N'-(α, α'-4,4'-dimethylenecyclohexane) bismaleimide, N, N'-m-
Xylylene bismaleimide, N, N '-(4,4'-diphenylcyclohexane) bismaleimide, N, N'-
(4,4'-diphenyl-1,1-propane) bismaleimide, N, N '-(4,4'-triphenyl-1,
1,1-ethane) bismaleimide, N, N '-(4,
4'-triphenylmethane) bismaleimide, N, N '
-(3,5-triazole) -1,2,4-bismaleimide, N, N '-(3,3'-dimethyl-4,4'-diphenylmethane) bismaleimide, N, N'-(3,
3'-diethyl-5,5'-dimethyl-4,4'-diphenylmethane) bismaleimide, 2,2-bis [4-
(4-maleimidophenoxy) phenyl] propane, bis [4- (4-maleimidophenoxy) phenyl] sulfone, bis (3-chloro-4-maleimidophenyl) methane and the like.

(Iii) Polymaleimide Compound Aromatic polymaleimide which is a maleimidated product of a condensate of aniline and formaldehyde (Japanese Patent Laid-Open No. 50-10).
See Japanese Patent Publication No. 900). A tetrafunctional aromatic polymaleimide which is a maleimidated product of a reaction product of an aromatic dialdehyde and an aromatic amine (see JP-B-3-3659). Aromatic polymaleimide, which is a maleimide compound of polyamine obtained from a mixture of aromatic dialdehyde and formaldehyde, and aromatic amine (JP-A-60-2603).
No. 2). An aromatic polymaleimide which is a maleimidated product of a reaction product of a hydroxyl group-containing aromatic aldehyde and an aromatic amine (see JP-A-60-197732).

In addition, maleimide compounds of polymers of vinylaniline, trimaleimidebenzene, trimaleimidetoluene trimaleimide diphenylmethane, tri (maleimide) phosphine oxide, tetramaleimide benzophenone, tetramaleimidonaphthalene, tetramaleimidophenyl sulfone, bis (dimaleimide) Phenyl) pyridine and the like.

(Curing agent for epoxy resin) As a curing agent for the epoxy compound which is the component (C) of the composition of the present invention, a general curing agent for epoxy resin is used. For example: Amines; aliphatic amines such as triethylenetetramine, tetraethylenepentamine, N-aminoethylpiperazine and isophoronediamine, aromatic amines such as metaphenylenediamine, diaminodiphenylmethane and diaminodiphenylsulfone

Acid anhydrides; aromatic acid anhydrides such as phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and cyclic fats such as tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and hexahydrophthalic anhydride Group anhydrides. Polyphenols; bisphenol F, bisphenol A, novolac phenol resin, parahydroxystyrene resin, etc. Latent curing agents: dicyandiamides, organic acid hydrazides, etc.

(Basic catalyst) Examples of the basic catalyst which is the component (D) of the present invention include the following. Tertiary amines; triethylamine, tri-n-butylamine, benzyldimethylamine, triethanolamine, trisdimethylaminomethylphenol, 1,8-diazabicyclo (5,4,4)
0) Tertiary amines such as undecene-7, and salts of tertiary amines with triacetate or tribenzoate.

Imidazoles; 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-
Isopropylimidazole, or their azine derivative, trimellitic acid derivative and nitrile ethyl derivative. Phosphine derivatives; triphenylphosphine, tricyclohexylphosphine, tributylphosphine,
Methyldiphenylphosphine, dibutylphenylphosphine, etc.

The performance of the thermosetting resin composition of the present invention can be changed by changing the blending ratios of the above components (A), (B), (C) and (D). In particular,
It can be appropriately adjusted depending on the method of use, the required performance and the application. That is, when heat resistance is required,
It is preferable that the compounding ratio of the component (A) is small, while on the other hand, in the case where importance is attached to the adhesiveness and the electrical characteristics, (A)
It is preferable to use many components. From this perspective,
In order to satisfy the heat resistance, the adhesiveness and the electrical characteristics, the compounding ratio of the components (A) and (B) is 100 for the component (A).
The component (B) is preferably in the range of 1 to 100 parts by weight with respect to parts by weight.

Since the component (C) acts as a curing agent for the component (A), it is preferably used stoichiometrically with respect to the component (A), and the component (D) acts as a catalyst.
Used while optimally adjusting the curing speed. If too much is used, the moisture resistance will deteriorate. From this point of view, the mixing ratio of the components (C) and (D) is 1 to 200 parts by weight of the component (C) and (D) with respect to 100 parts by weight of the component (A).
It is preferred that the components are in the range of 0.001 to 10 parts by weight.

(Optional Components) The epoxy resin composition of the present invention may contain the following components, if necessary. Powdery reinforcing agents and fillers, for example, metal oxides such as aluminum oxide and magnesium oxide, metal oxides such as aluminum hydroxide, metal carbonates such as calcium carbonate and magnesium carbonate, diatomaceous earth powder, basic magnesium silicate. , Calcined clay, fine powder silica, fused silica, crystalline silica, carbon black, kaolin, fine powder mica, quartz powder, metal hydroxide such as aluminum hydroxide, graphite, asbestos, molybdenum disulfide,
Such as antimony trioxide. Further, there are fibrous reinforcing materials and fillers, for example, inorganic fibers such as glass fiber, rock wool, ceramic fiber asbestos, and carbon fiber, and synthetic fibers such as paper, pulp, wood flour, linter, and polyamide fiber. The amount of these powdery or fibrous reinforcing materials and fillers used varies depending on the application, but as a laminated material or molding material, the resin composition 100 is the sum of the components (A), (B), (C) and (D). 5 parts by weight
Up to 00 parts by weight can be used.

Colorants, pigments, flame retardants such as titanium dioxide, yellow lead carbon black, iron black, molybdenum red,
Examples include dark blue, ultramarine blue, cadmium yellow, cadmium red, inorganic phosphorus such as red phosphorus, and organic phosphorus such as triphenyl phosphate. Further, various synthetic resins can be blended for the purpose of improving the properties of the resin in the final coating film, adhesive layer, resin molded product and the like. For example, phenol resin, alkyd resin, melamine resin, fluororesin, vinyl chloride resin,
One or a combination of two or more of acrylic resin, silicone resin, polyester resin and the like can be mentioned. The amount of these resins used is preferably within a range that does not impair the original properties of the resin composition of the present invention, that is, less than 50% by weight of the total amount of resin.

(A) component, (B) component, (C) component,
Examples of means for blending the component (D) and various additives include heat-melt mixing, kneading using a roll, a kneader, and the like, mixing using an appropriate organic solvent, and dry mixing.

(Curing Method) For coating and curing the resin composition obtained in the present invention, a substrate such as metal, plastic or glass degreased with a solvent such as acetone or trichlene is used with an applicator, a spin coater or a spray gun. Then, it is applied in a film thickness range of 0.1 to 500 μm and then heat-cured in a curing temperature range of 100 to 250 ° C. to obtain a cured coating film having excellent heat resistance.

[0027]

EXAMPLES The present invention will be described in more detail below with reference to examples. Example 1 50 parts by weight of diglycidyl ether of bisphenol A "Epicoat 828" (manufactured by Yuka Shell Epoxy Co., Ltd.), N,
N '-(3,3'-diethyl-5,5'-dimethyl-
10 parts by weight of 4,4′-diphenylmethane) bismaleimide and 40 parts by weight of methyltetrahydrophthalic anhydride were placed in a flask and stirred at a temperature of 80 ° C. to form a uniform solution. After lowering the temperature to 60 ° C., 0.5 parts by weight of 2-undecylimidazole acrylonitrile adduct “C ₁₁ Z-CN” (manufactured by Shikoku Kasei) was added and uniformly dissolved to obtain a resin composition.

Next, the above composition was placed on an aluminum plate using an applicator, and the width was 30 mm, the length was 100 mm, and the thickness was 3 mm.
After making a film of 0 μm, it was placed in an oven at 150 ° C for 16
It was cured for a time to obtain a cured film.

Examples 2 to 8 and Comparative Examples 1 and 2 Cured films were obtained in the same manner as in Example 1, except that the compositions having the formulations shown in Table 1 were used. Table 1 shows the physical property values of these cured films.
The cure rate is shown in FIG.

[0030]

[Table 1] * 1 Diglycidyl ether of bisphenol A (made by Yuka Shell Epoxy Co., Ltd.) * 2 Diglycidyl ether of bisphenol F (
〃) * 3 Epoxidized phenol novolac (
〃) * 4 N, N '-(3,3'-diethyl-5,5'-
Dimethyl-4,4'-diphenylmethane) bismaleimide * 5 N, N '-(4,4'-diphenylmethane) bismaleimide * 6 2,2'-[4- (4-maleimidophenoxy) phenyl] propane * 7 Poly Maleimide (manufactured by Mitsubishi Petrochemical) * 8 Methyltetrahydrophthalic anhydride (manufactured by Hitachi Chemical) * 9 Dicyandiamide * 10 2-Acrylonitrile adduct of 2-undecylimidazole (manufactured by Shikoku Kasei) * 11 2-Ethyl-4-methyl -Imidazole * 12 2-Dicyandiamide adduct of 2-undecylimidazole (manufactured by Shikoku Kasei) * 13 〃 trimellitic acid adduct * 14 Ultrafine silica (manufactured by Nippon Aerosil Co., Ltd.) * 15 RD-8 (manufactured by Tatsumori Industry Co., Ltd.) * 16 JIS-K-5400 * 17 TMA Penetration Method Temperature rising at 10 ° C / min in N _2. * 18 JIS-K-5400

[Brief description of drawings]

FIG. 1 is a graph showing changes in surface hardness of compositions of Examples 1 and 4 and Comparative Example 1 depending on a curing time.

Claims (3)

[Claims] 1. An epoxy resin composition comprising (A) an epoxy resin having at least two epoxy groups in one molecule, (B) a maleimide compound, (C) a curing agent for epoxy resin, and (D) a basic catalyst. 2. The maleimide compound as the component (B) is 1 to 100 parts by weight relative to 100 parts by weight of the epoxy resin as the component (A).
1 to 20 parts by weight of (C) component curing agent for epoxy resin
0 parts by weight and 0.001 part of the basic catalyst of component (D)
The composition according to claim 1, which is blended in a ratio of 10 parts by weight. 3. A composition comprising (A) an epoxy resin having at least two epoxy groups in one molecule, (B) a maleimide compound, (C) a curing agent for epoxy resin, and (D) a basic catalyst, A method for curing an epoxy resin composition, which comprises curing at a film thickness of 0.1 to 500 μm and a curing temperature of 100 to 250 ° C.