JPS5845234A - Manufacture of epoxy resin laminated board - Google Patents

Abstract

PURPOSE:To obtain the titled laminated board having excellent flame retardance and processability, by preliminarily impregnating a melamine-modified phenolic resin, etc. into a substrate, impregnating the substrate with epoxy resin and drying the impregnate to obtain a prepreg, and laminating the prepreg sheets. CONSTITUTION:A substrate (e.g. linter paper) is preliminarily impregnated with a melamine-modified or guanamine-modified phenolic resin (obtained by reacting a mixture of melamine, etc. and a phenolic compound with formaldehyde in the presence of an alkaline catalyst), and dried to obtain a preliminarily impregnated substrate containing 5-30(wt)% resin. An epoxy resin is impregnated into the substrate and dried to abtain a prepreg containing 29-75% resin as a whole. The objective laminated board can be manufactured by inserting a desired number of the prepreg sheets between a pair of pressure-equalizing plates, and hot-pressing with a hydraulic press with hot plate, etc. at about 100-200 deg.C and 30-150kg/cm<2> pressure. USE:Raw material of electrical parts, structural material, material for mechanical parts, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a method for manufacturing an epoxy resin laminate having excellent flame resistance and processability.

In recent years, with the development of various industries, excellent performance has been required for electrical component materials, structural materials, and mechanical component materials.In particular, synthetic resin laminates used in electrical and electronic equipment have extremely excellent performance and a wide range of performance characteristics. Items are now required. In other words, it has good electrical insulation and high frequency characteristics.
Excellent moisture resistance and water resistance, good mechanical performance, and heat resistance.
Furthermore, it is desired to have excellent flame resistance and processability, high value as a product, and low cost. One such synthetic resin laminate is an epoxy resin laminate in which a base material such as paper or glass is impregnated with epoxy resin. However, the expected high performance may not be obtained. Conventionally, as a countermeasure against this problem, it has been proposed to pre-impregnate and dry the base material with a phenol resin, melamine resin, amino resin or phenol resin-rubber.

With the pretreatment methods using these resins that have been known so far, significant improvements in electrical insulation, water absorption, etc. can be seen compared to cases without pretreatment, but flame resistance and processability are still insufficient. However, the current situation is that there are considerable restrictions on its use.

The present invention aims to provide an epoxy resin laminate that has good flame resistance and processability as well as other properties.

As a result of various studies on this problem, the present inventors have found that a base material is pre-prepared with a product obtained by reacting formaldehyde with melamine or/and a mixture of guanamines and phenols (hereinafter referred to as melamine-modified or guanamine-modified phenolic resin). Through this treatment, we succeeded in obtaining an epoxy resin laminate that has excellent general properties such as electrical insulation, high frequency properties, heat resistance, and water absorption, as well as extremely good flame resistance and workability.

That is, in the manufacturing method of the present invention, a base material is pre-impregnated with a melamine-modified or guanamine-modified phenol resin and dried to obtain a pre-impregnated base material containing a resin content of 5 to 30% by weight, and the pre-impregnated base material is pre-impregnated with an epoxy resin. After impregnating and drying, the total resin content is 29 ~
This is a method for producing an epoxy resin laminate, which is characterized by forming a prepreg containing 75% by weight, and laminating and molding the obtained prepreg.

The base materials used in the manufacturing method of the present invention include epoxy resin, such as linter paper, kraft paper, cotton cloth, synthetic fiber cloth or non-woven fabric thereof, glass non-woven fabric, asbestos paper, mixed paper of linter and glass, mixed paper of linter and asbestos, etc. It is a base material that does not have sufficient bonding properties, and also includes base materials made from auxiliary materials such as paper made from antimony oxide.

The melamine-modified or guanamine-modified phenolic resin used in the present invention is prepared by adding a mixture of melamine or/and guanamines (acetoguanamine, benzoguanamine, etc.) and phenols such as phenonohecresol, xylenol, impropylphenol, bisphenol A, etc. to metallic water. It is reacted with formaldehyde under an alkaline catalyst such as an oxide or an alkylamine. The amount of denaturation of melamine or guanamine is not limited.

The epoxy resin used in the present invention is a compound obtained by reacting [F] polyhydric phenol, polyvalent polynuclear phenol, or aliphatic polyhydric alcohol with epihalohydrin or Hashihalohi)' IJ 7 in an alkaline catalyst by a known method. , ■ Compound obtained by epoxidizing an alicyclic compound or aliphatic compound containing a diene by peracid oxidation, ■
Examples include halogenated compounds of the above compounds and (2). Curing agents can be used alone or in conjunction with curing accelerators. Examples of the curing agent include aliphatic or aromatic polyamines, acid anhydrides, polyamides, dicyandiamide, benzyldimethylamine, and the like. Further, known flame retardants (for example, tricresyl phosphate, dibromophenyl glycidyl ether) and other additives may be mixed as necessary.

The resin content of the melamine-modified or guanamine-modified phenol resin to be impregnated into the base material in the pre-impregnation treatment is suitably in the range of 5 to 30% by weight based on the pre-impregnated and dried pre-impregnated base material. Next, the amount of epoxy resin impregnated into the pre-impregnated base material is such that the total resin content of melamine-modified or guanamine-modified phenol resin and epoxy resin is in the range of 29 to 75% by weight based on the impregnated and dried silipreg. is suitable. The resin content is calculated from the dry weight of a certain area of the substrate, pre-impregnated and dried and prepreg left in an air dryer at 150° C. for 30 minutes. The drying loss at that time is regarded as volatile matter.

In this way, the melamine or guanamine component of the pre-impregnated melamine-modified or guanamine-modified phenolic resin contributes to improving flame resistance, and the phenol component improves impact resistance and processability. Impregnation provides excellent general properties such as electrical insulation, high frequency properties, heat resistance, and water absorption. The resin content range of the above-mentioned melamine-modified or guanamine-modified phenol resin and epoxy resin is the range in which flame resistance, processability, and film properties can be maintained.

Laminate molding of prepreg made by impregnating a pre-impregnated base material with epoxy resin and drying it is usually done by sandwiching a predetermined number of prepreg sheets between two patch plates, using a hydraulic press with a hot plate, etc.
They are heated and pressed at a temperature of 200°C, a pressure of 30~Tso#, and are integrated. An epoxy resin laminate can be replaced by using only the prepreg of the present invention, and a copper-clad epoxy laminate can be replaced by stacking and molding copper foil on at least one outside surface of the prepreg. In addition to the shape of a laminated plate, those in the shape of a laminated tube or a laminated rod are also available. Furthermore, a resin-impregnated base material other than the present invention can be used in combination with a part of the prepreg of the present invention.

Since the epoxy resin laminate produced by the manufacturing method of the present invention uses an appropriate amount of melamine-modified or guanamine-modified phenol resin as the pre-impregnated resin, it has flame resistance and impact cracking resistance, that is, punching workability and shearing workability, which were previously insufficient. could be improved at the same time. It has good general properties such as electrical insulation, high frequency properties, heat resistance, and water absorption on average, and has well-balanced performance in addition to flame resistance and workability. In particular, the performance of epoxy resin laminates using cellulose-based, synthetic fiber-based, or asbestos-based base materials is significantly improved compared to laminates made by conventional methods.

The present invention will be explained in detail below. The terms "part" and "part" below refer to parts by weight and percent by weight, respectively.

Example 1 100 parts of phenol, 1050 parts of melamine, 1200 parts of 37% formalin, and 10 parts of triethylamine were mixed,
After reacting at 80° C. for 90 minutes and dehydrating under reduced pressure, methanol was added to obtain a resin solution (A) with a solid content of 50 cm.

100 parts of epoxy m resin (bisphenol A type epoxy resin: epoxy equivalent: 500) and 35 parts of het acid anhydride as a hardening agent were dissolved in acetone to give a solid content of 50 parts.
A second resin solution (B) was obtained. This resin solution (B) is mixed with 7 parts of dibromophenyl glycidyl ether and 4 parts of tricresyl phosphate to form a resin solution (C).

Resin solution (A) on linter paper with basis weight 150.1//d
was pre-impregnated and dried at 150°C to obtain a B-stage pre-impregnated paper with a resin content of 30% and a volatile content of 1.9%. The obtained pre-impregnated paper was impregnated with the resin solution (C) and heated at 150°
Dry at C, total resin content of B stage is 60%.

A prepreg with a volatile content of 1.9 was obtained.

Seven sheets of this prepreg were stacked, a copper foil with a thickness of 35 μm was placed on one side of the prepreg, and heated under pressure at 170°C and 70 kg/ca for 70 minutes, cooled, and a copper-clad laminate with a thickness of 1.6 μm was formed. Obtained.

Table 1 shows the results of testing its properties and the applicable test methods.

Example 2 100 parts of phenol, 11 parts of melamine, 280 parts of 37% formalin, and 1 part of triethylamine were mixed and reacted at 8°C for 1.10 minutes. After dehydration under reduced pressure, methanol was added to prepare a resin with a solid content of 50 cm. A solution (D) was obtained.

Epoxy resin (bisphenol A type epoxy resin: Epoquine equivalent: 500. Br amount: 18%) The loo part and 15 parts of phthalic anhydride (curing agent) are dissolved in acetone to make a resin solution (E) with a solid content of 50%. Obtained.

Resin solution (D) on linter paper with basis weight 1501//nf
was pre-impregnated and dried at 150° C. to obtain a B-stage pre-impregnated paper with a resin content of 30% and a volatile content of 19%. The obtained pre-impregnated paper was impregnated with the resin solution (E) and dried at 150°C to obtain a B-stage prepreg with a total resin content of 60% and a volatile content of 19%.

Using this prepreg, a copper-clad laminate was obtained in the same manner as in Example 1, and the test results are shown in Table 1.

Example 3 100 parts of phenol, 1100 parts of benzoguanamine, 3
7. 850 parts of formalin were mixed, reacted at 80°C for 4 hours, dehydrated under reduced pressure, and then acetone was added to reduce the solid content to 80.
% resin solution (F) was obtained.

Copper-clad laminates were obtained in the same manner as in Example 1 using resin solution (F) and resin solution (E) (see Example 20), and the test results are shown in Table 1.

Example 4 100 parts of phenol, 1050 parts of acetoguanamine, 3
1160 parts of 7% formalin and 10 parts of triethylamine were mixed, reacted at 80°C for 3 hours, dehydrated under reduced pressure, and then acetone was added to obtain a resin solution (G) with a solid content of 50%.

100 parts of an epoxy resin (bisphenol A type epoxy resin: epoxy equivalent: 500) and 40 parts of Het's acid anhydride (curing agent) were dissolved in acetone to obtain a resin solution (H) with a solid content of 50 cm. This resin solution (H) was mixed with 8 parts of tetrabromodiphenyl ether to form a resin solution (I).

A copper-clad laminate was obtained using the resin solution (H) and the resin solution (I) in the same manner as in Example 1, and the test results were
Shown in the table.

Example 5 A glass cloth with a basis weight of 135 g/z7/ was impregnated with a resin solution (H) of Evokin resin (see the section of Example 4), and
It was dried at 50°C to obtain an adhesive prepreg with a resin content of 45%.

6 sheets of prepreg obtained in Example 1 are stacked, 1 sheet of adhesive prepreg is placed on top and bottom of the prepreg, and 3 sheets of prepreg are stacked on one side.
Copper foils having a thickness of 5μ were laminated and molded in the same manner as in Example 1 to obtain a copper-clad laminate, and the test results are shown in Table 1.

Comparative Example 1 100 parts of phenol, 110 parts of 37q6 formalin, and 5 parts of triethylamine were mixed, reacted at 80°C for 100 minutes, dehydrated under reduced pressure, and then acetone was added to reduce the solid content to 50.
% resin solution (J) was obtained.

Copper-clad laminates were obtained in the same manner as in Example 1 using resin solution (J) and resin solution (C) (see Example 1), and the test results are shown in Table 1.

Comparative Example 2 Mixing 100 parts of melamine and 100 parts of 37% formalin
After reacting at .degree. C. for 3 hours and dehydrating under reduced pressure, methanol was added to obtain a resin solution (K) with a solid content of 80%.

Copper-clad laminates were obtained in the same manner as in Example 1 using resin solution (K) and resin solution (E) (see Example 2), and the test results are shown in Table 1.

Claims (1)

[Claims] 1 A base material is pre-impregnated and dried with a melamine-modified or guanamine-modified phenol resin to obtain a pre-impregnated base material containing a resin content of 5 to 30% by weight, and the above pre-impregnated and dried is impregnated and dried with an epoxy resin to obtain a total resin content of 29 to 30% by weight. A method for producing an epoxy resin laminate, comprising preparing a prepreg containing 75% by weight, and laminating and molding the obtained prepreg.