JPS60240743A - Electrical laminate - Google Patents

Abstract

PURPOSE:An electrical laminate having low water absorptivity and excellent insulation resistance, high-frequency characteristics, punching and drilling qualities, etc., obtained by laminating a required number of plies of impregnated reinforcements, prepared by impregnating a sized glass cloth with a fluororesin which is heat-melted. CONSTITUTION:A glass cloth having a sizing (e.g. organic materials such as a starch, an oil or a fat) applied thereon is impregnated with a dispersion of a fluororesin (e.g. teterfluoroethylene resin), and this resin is heat-melted to give an impregnated reinforcement. Then, a required number of plies of the impregnated reinforcements are laid up, if necessary, with a metal foil such as a copper foil laid at least on one side, heated and pressed at about 400 deg.C and 30kg/cm<2> for about 45min to give the electrical laminate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an electrical laminate used in electronic equipment and the like.

[Background technology]

The following types of electrical laminates have been considered. That is, a predetermined sheet of a resin-impregnated base material is prepared by impregnating a glass cloth with a fluororesin by soaking a glass cloth (including nonwoven fabric) in a fluororesin dispersion or coating the glass cloth with a fluororesin dispersion. It is molded under heat and pressure, with metal foil such as copper foil placed on one or both sides as required. Electrical laminates using fluororesin have excellent performance.

[Purpose of the invention]

This invention has very low water absorption and insulation resistance.

The purpose of the present invention is to provide an electrical laminate with exceptional performance in terms of punching workability, drilling workability, high frequency properties, moisture resistance, heat resistance, chemical resistance, etc.

[Disclosure of the invention]

The inventor conducted repeated research in an attempt to obtain a product with even better performance by improving the electrical laminate.

As a result, they found that it was sufficient to use glass cloth to which a sizing agent was attached, and this invention was thus completed.

Therefore, the present invention provides an electrical laminate formed by laminating and molding a predetermined number of resin-impregnated base materials obtained by impregnating a glass cloth with a fluororesin and then heating and melting the same. The gist is an electrical laminate that is characterized by:

The present invention will be explained in detail below.

Here, the glass cloth (including glass nonwoven fabric) to which the sizing agent is attached is generally of a type called gray fabric. This type can be said to be an intermediate product when manufacturing glass cloth (glass fiber) used to impregnate resins such as epoxy resin and polyimide resin.
This is a glass monofilament with a sizing agent still attached.

A sizing agent is used for the purpose of adhering the monofilaments to each other when the monofilaments are drawn together to form a yarn or strand in the production of glass fibers, and is usually used through heat cleaning treatment, etc. It is removed by Therefore, glass cloth coated with a sizing agent is not normally used as a substrate. Examples of the sizing agent include starch, fats and oils, and organic substances are preferred.

As the fluororesin, tetrafluoroethylene resin (PTFE
), tetrafluoroethylene-hexafluoropropylene copolymerization +M
(FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), etc. are used.

The electrical laminate according to the present invention is manufactured as follows.

First, a glass cloth coated with a sizing agent is impregnated with a fluororesin, and then the resin is heated and melted (sintered) to create a resin-impregnated base material. The impregnation is performed, for example, by dipping the glass cloth in a fluororesin dispersion or by applying a fluororesin dispersion to the glass cloth. Next, a predetermined number of resin-impregnated base materials are stacked, and if necessary, metal foil such as copper foil is stacked on at least one side to form a laminate, and this laminate is heat-formed (integrated) to form an electrical laminate. Get a board.

The electrical laminate thus obtained uses glass cloth coated with a sizing agent, so it has low water absorption, insulation resistance, punching workability, drilling workability, high frequency characteristics, moisture resistance, and heat resistance. Excellent properties such as durability and chemical resistance. This is because the glass cloth to which the sizing agent is attached is most suitable for impregnating and sintering the fluororesin.

In addition, if a fluororesin film is interposed between the resin-impregnated base materials, and if necessary, the fluororesin films are superimposed on the outside of the resin-impregnated base materials on both outer surfaces as well.
It is possible to obtain an electrical laminate with even better performance such as drill workability and punching workability.

Next, Example 1 to explain Examples and Comparative Examples
．． Electrical laminates of Comparative Examples 1 and 2 and Comparative Examples 1 and 2 were produced as follows.

(Example 1) A glass cloth coated with a starch sizing agent with a thickness of 0.05+n was impregnated with a tetrafluoroethylene resin dispersion so that the amount of resin was 45%, and then the resin was heated and melted at 350°C to form a resin. An impregnated base material was made. Twelve sheets of this resin-impregnated base material are stacked together, and a thickness of 0,018 mm is added to the top and bottom surfaces.
A laminate was made by overlapping adhesive-coated copper foils. This laminate was heat-pressed and molded under conditions of 30 kg/cJ, 400° C., and 45 minutes to obtain an electrical laminate.

(Example 2) A 0.05 m thick oil-coated glass cloth was impregnated with a tetrafluoroethylene resin dispersion so that the resin amount was 45%, and then the resin was heated and melted at 350°C to make a resin-impregnated base material. I made it. Nine of these resin-impregnated base materials were stacked one on top of the other with a 0.03 m thick polytetrafluoroethylene resin film sandwiched between the resin-impregnated base materials, and a 0.018 m thick adhesive-coated copper film was placed on the top and bottom surfaces of the 0.03 m thick polytetrafluoroethylene resin film. A laminate was created by overlapping the foils. This laminate was molded under heat and pressure under the same conditions as in Example 1 to obtain an electrical laminate.

(Comparative Example 1) An electrical laminate was obtained in the same manner as in Example 1, except that a heat-cleaned glass cloth with a thickness of 0.05 m from which the sizing agent had been removed by heating was used.

(Comparative Example 2) An electrical laminate was prepared in the same manner as in Example 1, except that after the sizing agent was removed by heating, a 0.05 inch thick glass cloth whose surface was treated with an organic silane compound was used. I got it.

Water absorption rate (D-2/100, 2-hour treatment in 100°C water) for the electrical laminates of Examples 1 and 2 and Comparative Examples 1 and 2
, insulation resistance (I)-2/100).

Drilling workability and punching workability were investigated.・Results first
Shown in the table.

Table 1 From Table 1, the electrical laminate of Example 1.2 has a lower water absorption rate and insulation resistance than that of the comparative example.

It can be seen that drill workability and punching workability are excellent.

〔Effect of the invention〕

The electrical laminate according to the present invention uses a glass cloth to which a sizing agent is attached, so it has very low water absorption, good insulation resistance, punching workability, drilling workability, high frequency properties, and moisture resistance. properties, heat resistance.

Excellent performance such as chemical resistance.

Agent: Patent Attorney Takehiko Matsumoto

Claims (2)

[Claims] (1) In electrical laminates made by laminating and molding predetermined sheets of a resin-impregnated base material made by impregnating a glass cloth with fluororesin and then heating and melting the same, the glass cloth to which a sizing agent is attached is used. An electrical laminate board characterized by: (2) The electrical laminate according to claim 1, wherein the sizing agent is an organic substance.