JPH0680947A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain an epoxy resin compsn. excellent in heat resistance by compounding an epoxy resin, a specific polyalkylene oxide adduct or its glycidyl ether, diaminodiphenyl sulfone, a cure accelerator, and an inorg. filler. CONSTITUTION:An epoxy resin compsn. excellent in heat resistance is prepd. by premixing and then completely mixing, e.g. on a mixing roll, 100 pts.wt. epoxy resin of a novolac type, a phenol-novolac type, etc., 10-50 pts.wt. at least one compd. selected from the group consisting of a bisphenol-based polyalkylene oxide adduct, its glycidyl ether, a novolac-phenol-based polyalkylene oxide adduct, and its glycidyl ether, 0.8-1.2 equivalents of a curative such as diaminodiphenyl sulfone, 0.5-1.5 pts.wt. at least one cure accelerator selected from the group consisting of an imidazole compd., a BF3-amine complex, and dicyandiamide, and an inorg. filler such as Al2O3 in an amt. of 60-80wt.% based on the solid content of the compsn.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an epoxy resin composition. More specifically, the present invention relates to an epoxy resin composition suitable for laminating a metal or ceramic base material and a metal foil, and particularly suitable as an insulating adhesive layer for a high heat dissipation wiring board.

[0002]

2. Description of the Related Art A high heat radiation wiring board comprises a metal or ceramic base material, a metal foil, and an insulating adhesive layer for bonding the both. For the insulating adhesive layer, a mixture of an epoxy resin with a curing agent and an inorganic filler (filler) and a mixture of a phenol resin with an inorganic filler are used. In manufacturing a high heat dissipation wiring board using an epoxy resin composition as an insulating adhesive layer, the epoxy resin composition is applied to one side of a metal foil, and this is temporarily cured (B-Stage).
After that, it is adhered to the base material and pressed and cured, or the epoxy resin composition is applied to both the base material and the metal foil, and this is preliminarily cured, and then both are A method of bringing them into close contact, pressurizing, and curing is adopted.

[0003]

Thus, the epoxy resin composition used as the insulating adhesive layer of the wiring board has a long pot life after preparation (preparation) and is stable. Wide B-St to obtain a temporary cured state
Age range, high adhesive strength, low thermal resistance (high thermal conductivity) of cured products, and heat resistance of cured products when joining electronic components by soldering are required. Further, flexibility is required when the epoxy resin composition is applied to the metal foil and the prepreg that has been temporarily cured is wound and stored. However, there is no epoxy resin composition that can satisfy all of these conditions in a well-balanced manner.

[0004]

Means for Solving the Problems The present invention satisfies all of the above conditions: (A) epoxy resin, (B) (1) bisphenol-based polyalkylene oxide adduct, (2) novolac-based phenol. Polyalkylene oxide adduct of (3) bisphenol-based polyalkylene oxide adduct glycidyl ether,
(4) Any one kind or a mixture of two or more kinds of glycidyl ethers of polyalkylene oxide adducts of novolac phenols, (C) diaminodiphenyl sulfone, (D) (a) imidazole compound, (b) boron trifluoride amine. Epoxy resin composition comprising a complex compound, (c) a mixture of any one or more of dicyandiamide, and (E) an inorganic filler of 60 to 80% by weight of solid content as an essential component Provide things.

The epoxy resin used in the present invention is preferably a novolac type epoxy because heat resistance is required, and examples thereof include phenol novolac type and cresol novolac type. In addition, bisphenol A type, bisphenol F type and the like can also be used. These epoxy resins may be used alone or in combination of two or more kinds.

The epoxy resin composition of the present invention has, as additives, (1) a bisphenol-based polyalkylene oxide adduct, (2) a novolac-based phenol polyalkylene oxide adduct, and (3) a bisphenol-based polyalkylene oxide. Glycidyl ether of adduct,
(4) It contains any one kind or a mixture of two or more kinds of glycidyl ether of a polyalkylene oxide adduct of novolac phenol. By containing these additives, the flexibility of the provisionally cured state is increased, and the provision of the provisionally cured metal foil prepreg is facilitated. Further, it becomes easy to punch through holes when used as a wiring board. The amount of these additives used is preferably 10 to 50 parts by weight with respect to 100 parts by weight of the epoxy resin.

In the present invention, diaminodiphenyl sulfone (hereinafter abbreviated as DDS) is used as a curing agent. DDS provides a high adhesive force, especially with a copper foil, in combination with an epoxy resin, and has a longer pot life, a wider B-Stage width, and heat resistance. D
The amount of DS used is preferably 0.8 to 1.2 chemical equivalents.

The curing reaction between the epoxy resin and DDS is carried out at a high temperature for a long time (200 ° C., 4 hours), and a temporary cured state cannot be easily obtained. Therefore, in the present invention, any one kind or a mixture of two or more kinds of (a) imidazole compound, (b) boron trifluoride amine complex compound, and (c) dicyandiamide is used as a curing accelerator. By using these curing accelerators, the curing reaction start temperature is lowered and a temporary cured state can be easily obtained. In particular, the pot life becomes longer when an imidazole compound with an azine is used. Also, the combination of these cure accelerators with DDS provides greater flexibility in the pre-cured state. The amount of these curing accelerators used is preferably 0.5 to 1.5 parts by weight with respect to 100 parts by weight of the epoxy resin, and if it is within this range, the required properties of the adhesive described above are not lost,
It is possible to improve the curing conditions and increase the advantages, which are disadvantages. 0.
If it is less than 5 parts by weight, the curing acceleration effect does not work, and if it exceeds 1.5 parts by weight, the curing accelerator itself acts as a hardening agent, which is an advantage when DDS works as a hardening agent. The characteristics such as life, wide B-Stage width, and flexibility in the pre-cured state are deteriorated. Furthermore, the epoxy resin composition of the present invention contains an inorganic filler having a solid content of 6%.
By containing 0 to 80% by weight, the cured product has excellent thermal conductivity.

[0009]

EXAMPLES The present invention will be described below with reference to examples. Examples 1 to 5 and Comparative Examples 1 to 6 The formulations shown in Table 1 and Table 2 were premixed with a premixer and then thoroughly kneaded with a three-roll mill to prepare epoxy resin compositions. The epoxy resin composition was applied to a copper foil and then temporarily cured, and the temporarily cured copper foil prepreg was hot-pressed with an aluminum plate. The following evaluation tests were performed on the epoxy resin composition in these processes. That is, the pot life of the epoxy resin composition, the B-Stage width, the flexibility at the time of prepreg, the curing conditions, the adhesion of the copper foil to the aluminum plate, the heat dissipation, and the punching evaluation test were conducted. The results of these evaluation tests are shown in Tables 1 and 2.

[0010]

[Table 1]

[0011]

[Table 2]

The pot life was measured by measuring the viscosity immediately after the epoxy resin composition was prepared and 10 days later (preserved under refrigeration at 7 ° C.), and the viscosity increased 10 times after the preparation was 5 times or more. Those that increased less than 5 times were rated as Δ, and those that increased less than 2 times were rated as ◯. The B-Stage width was broad when the time width from the time when the prepreg reached tack-free to when it was not completely adhered at a constant temperature of 100 ° C. was 30 minutes or more, and narrow when it was less than 30 minutes. Flexibility was evaluated by wrapping a prepreg around a tube having a diameter of 2 cm, in which a crack was generated x, in which no prepreg was bent into two, and a crack ◯ was generated. The item was marked as ◎. Adhesiveness is aluminum plate / epoxy resin composition /
For the structure of copper foil, measure the 90-degree peel strength of the copper foil from the aluminum plate, and in the case of 2 kg / cm or more, ○ 2 kg / cm
The case of less than was designated as x.

The curing condition is that the curing reaction is constant at 200 ° C.
The time was longer than that and the time was less than one hour. The heat dissipation was evaluated by measuring the heat resistance using an aluminum plate / epoxy resin composition / copper foil obtained by hot pressing. At this time, the thickness of the epoxy resin composition (insulating adhesive layer) is 80μ.
m, the thickness of the copper foil is 35 μm, and the thickness of the aluminum plate is 1.5 μm. For the evaluation of punching, punching was carried out on an aluminum plate / epoxy resin composition / copper foil obtained by hot pressing, and the epoxy resin composition in which no cracking occurred was evaluated as ○, and the one in which cracking occurred was evaluated as ×. And

[0014]

The epoxy resin composition of the present invention comprises (A)
Epoxy resin, (B) (1) bisphenol-based polyalkylene oxide adduct, (2) novolac-based phenol polyalkylene oxide adduct, (3) glycidyl ether of bisphenol-based polyalkylene oxide adduct, (4) novolak Any one kind or a mixture of two or more kinds of glycidyl ethers of a polyalkylene oxide adduct of a phenol system, (C) diaminodiphenyl sulfone, (D) (a) imidazole compound,
(B) Boron trifluoride amine complex compound, (c) any one kind of dicyandiamide, or a mixture of two or more kinds,
(E) 60% to 80% by weight of the solid content of the inorganic filler is contained as an essential component, so that it has a long pot life, an easily obtained temporary cured state, a wide B-Stage width, and an excellent temporary cured state. It has flexibility, high adhesive strength, and various properties such as excellent heat resistance, thermal conductivity, and punchability of the cured product at the same time. Therefore, the epoxy resin composition of the present invention is extremely useful as an insulating adhesive layer of a high heat dissipation wiring board in which a metal or ceramic base material and a metal foil are laminated, from the viewpoint of both characteristics and productivity.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication C08L 63/00 NJY 8830-4J H01B 3/40 G 9059-5G (72) Inventor Nobuyuki Nakamura Tokyo 2-6-1, Marunouchi, Chiyoda-ku Furukawa Electric Co., Ltd.

Claims (1)

[Claims] 1. (A) Epoxy resin, (B) (1) Bisphenol-based polyalkylene oxide adduct, (2) Novolac-based phenol polyalkylene oxide adduct, (3) Bisphenol-based polyalkylene oxide adduct. Glycidyl ether,
(4) Any one kind or a mixture of two or more kinds of glycidyl ethers of polyalkylene oxide adducts of novolac phenols, (C) diaminodiphenyl sulfone, (D) (a) imidazole compound, (b) boron trifluoride amine. Epoxy resin composition comprising a complex compound, (c) a mixture of any one or more of dicyandiamide, and (E) an inorganic filler of 60 to 80% by weight of solid content as an essential component object.