JPH064312B2 - Laminated board manufacturing method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminate having less deterioration of insulation resistance with time, particularly an epoxy resin laminate using a glass nonwoven fabric as a base material in part or in whole. .

2. Description of the Related Art Epoxy resin laminates having a glass nonwoven fabric as a base material are obtained by laminating and molding a prepreg obtained by impregnating glass nonwoven fabric with an epoxy resin and drying. From the viewpoint of mechanical strength and the like of a laminated board, a composite epoxy resin laminated board using a glass non-woven fabric as a core layer base material and a glass woven fabric as a surface layer base material is often used. As each base material, a base material treated with a coupling agent is used in order to enhance the bonding strength with the epoxy resin.

The conventionally used glass non-woven fabric treated with the coupling agent is a short glass fiber that has been previously treated with a coupling material, or a glass non-woven fabric that has been subjected to a coupling agent treatment after paper making.

Problems to be Solved by the Invention However, when the glass non-woven fabric is formed, a binder and a dispersant are added. Therefore, when the short glass fiber is previously treated with the coupling agent, the coupling agent is used during the paper making. The treated surface is covered with a binder or the like. In addition, even if the glass nonwoven fabric after papermaking is treated with a coupling agent,
The glass short fiber surface is already covered with a binder, etc.
The effect of the coupling agent directly binding the epoxy resin and the glass fiber is reduced.

Therefore, when the epoxy resin swells due to moisture absorption when it is used as a laminated plate, there is a problem that the bond between the glass fiber and the epoxy resin is peeled off, moisture enters through the glass fiber by the capillary phenomenon, and the insulation resistance decreases. In addition, when a printed circuit board using this laminated board as an insulating board is processed, complicated thermal history such as etching, cleaning, drying, and solder dipping is applied, and the expansion coefficient of epoxy resin and glass is different, so glass fiber and epoxy There is a drawback that the resin is peeled off and the insulation resistance of the product deteriorates quickly.

An object of the present invention is to provide a laminate having a glass non-woven fabric as a part or the whole of its base material, which improves the binding force between glass fiber and epoxy resin and has a small deterioration in insulation resistance due to moisture absorption. It is what

Means for Solving Problems The present invention is characterized in that, in order to achieve the above-mentioned object, a glass non-woven fabric produced by adding a coupling agent together with a binder or the like is used as the glass non-woven fabric.

By adding a coupling agent at the time of papermaking, the wettability between the glass fiber to be paper-made and the added binder or sizing agent is improved, and the coupling agent is also applied to the surface of the paper-made glass nonwoven fabric. Since it adheres, the wettability with the epoxy resin also becomes good. As a result, the adhesive force with the epoxy resin is increased, and peeling between the glass fiber and the epoxy resin due to swelling due to moisture absorption of the epoxy resin and expansion / contraction of the resin due to heating and cooling is less likely to occur.

The coupling agent referred to here is not particularly limited, such as a silane coupling agent and a titanium coupling agent. The laminate may be a metal foil clad laminate.

Example A glass non-woven fabric was used which was made by adding a binder containing 1 wt% of a silane coupling agent (Nippon Unica A-187) at the time of paper making.

A prepreg for a core material having a resin amount of 60 wt% was obtained by impregnating and drying the composition containing 100 parts by weight of an epoxy resin (Epicoat 1001 manufactured by Yuka Shell Co., Ltd.), 4 parts by weight of dicyandiamide, and 0.5 parts by weight of benzyldimethylamine into the glass nonwoven fabric. Got On the other hand, a glass woven cloth was impregnated with the same resin composition as above and dried to obtain a surface prepreg having a resin amount of 40 wt%.

Six core prepregs are stacked, one surface prepreg is stacked on each side of the core prepreg, and 35μ thick copper foil is placed on both sides of the core prepreg. Pressure is 30 kg / cm ² , and temperature is 150 ° C.
It heat-pressed for 0 minute and the double-sided copper clad composite laminated board was obtained.

Comparative Example As the glass non-woven fabric, a glass non-woven fabric was used which was soaked in a 1 wt% aqueous solution of a silane coupling agent similar to that of the example after papermaking and dried at 100 ° C. for 30 minutes with air drying. A double-sided copper-clad composite laminate was obtained in the same manner as in Example except for the above.

From the laminated plates obtained in Examples and Comparative Examples, a test piece for measuring insulation resistance was prepared according to JIS C-6481, and the insulation resistance was deteriorated after being left in saturated steam at 121 ° C. and 2 atm for 2 hours and 4 hours. Was measured and the results are shown in Table 1.

EFFECTS OF THE INVENTION As is clear from Table 1, in the present invention, the bonding strength between the glass fiber of the glass non-woven fabric and the epoxy resin can be increased to prevent the peeling of the two from occurring, thus preventing the intrusion of water due to the capillary phenomenon. Therefore, the industrial value thereof is extremely large in that the deterioration of the insulation resistance with time can be suppressed.

Claims (1)

[Claims] 1. A method for producing a laminated sheet, comprising laminating and forming a part or all of a prepreg obtained by impregnating and drying a glass nonwoven fabric with an epoxy resin, and as a glass nonwoven fabric, a coupling agent is added at the time of papermaking. A method for producing a laminated board, which comprises using the above-mentioned glass non-woven fabric.