JPS596227A - Production of laminated sheet - Google Patents

Abstract

PURPOSE:To obtain a laminated sheet which is free from resin exudation and defective appearance and has an excellent dimensional stability, by applying a hexamine solution to the side surfaces of a laminate body prepared by laminating prepregs prepared by impregnating bases with a phenolic resin varnish and drying the impregnated bases and applying heat and pressure to the laminate body. CONSTITUTION:Prepregs are prepared by impregnating bases (e.g., glass or paper) with a phenolic resin varnish and drying the impregnated bases. A necessary number of the prepared prepregs are laminated into a laminate body. Then, the side surfaces of the laminate body are coated with a hexamine solution at room temperature. Then, a laminated sheet useful in electrical devices and appliances, electronic devices and appliances, computer devices, etc., is obtained by application of heat and pressure thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a laminate used for electrical equipment, electronic equipment, computer equipment, etc., and its purpose is to prevent resin melt from flowing out from prepreg during laminate molding. By doing so, it is possible to obtain a laminate with excellent stability in one method, and to eliminate defects in the appearance of the laminate due to contamination of resin melt flow and cured material.

Conventionally, laminates are obtained by sandwiching a required number of laminates between molding plates and applying heat and pressure, and a decrease in the thickness of the laminate edge due to resin melting out from the laminate prepreg cannot be avoided (and Defects in the appearance of the laminate due to resin melt flow and contamination with cured products were unavoidable.

The present invention solves the above-mentioned drawbacks by impregnating a base material for a laminate with a phenol-based packing varnish, applying a hexamine solution to the side surface of the laminate made by stacking a certain number of dried prepregs, and then heating it. Since the hexamine accelerates the curing of the side surfaces of the laminate, the resin melt and outflow from the center of the laminate is inhibited, resulting in a laminate with no resin melt and outflow from the laminate, and therefore excellent in Torah stability. Moreover, since no resin melt outflow cured product is generated, it is possible to eliminate defects in the appearance of the laminate due to the contamination of the cured product.

The present invention will be described in a false manner below. The phenolic thread resin face used in the present invention is phenols such as phenol, cresol, and xylenol, or phenols and phenols, denaturable vegetable oils, molasses, naphthalene, lignin, xylene, petroleum resins, etc., and formaldehyde such as formaldehyde and rose formaldehyde. This is a general range of phenolic resin varnishes made by diluting phenolic resins or modified phenolic resins obtained by reacting with an alkali catalyst with a solvent such as water, methyl alcohol, acetone, toluene, etc., and can be used as a base material for laminates. These include woven fabrics, nonwoven fabrics, paper, or a combination of these materials made of inorganic fibers such as glass and asbestos, organic synthetic fibers such as polyester, polyamide, polyvinyl alcohol, and acrylic, and natural fibers such as cotton. The hexamine solution is one in which hexamine is dissolved in a solvent such as water, methyl alcohol, acetone, etc., and the type of solvent is not particularly limited as long as it dissolves hexamine. It is desirable to form a solution of hexamine at room temperature. As a result, the solubility decreases, and by adding a very small amount of acid, the solubility can be significantly improved. The hexamine solution may be applied to the side surface of the prepreg laminate by any method such as a spray method or a roll coating method, and is not particularly limited. Furthermore, the amount of coating is not particularly limited. Note that a copper-clad laminate can also be obtained by placing a copper foil on the upper surface or upper and lower figure numbers of the prepreg laminate.

The following is a theory I based on the present invention as an example. /J.

Example: Kraft paper with a thickness of 0.1s+w was impregnated with a phenolic resin varnish with a resin content of 50% (hereinafter simply referred to as %) so that the resin adhesion was 50%, and dried prepreg was
A 30% aqueous solution of hexamine is coated on the side surface of the stacked laminate using a roll coating method, and then it is sandwiched between molding plates and heated and pressed at a molding pressure of 100υ and a molding temperature of 160°C for 760 minutes to a thickness of 1°6-. A phenolic resin laminate was obtained.

A laminate of 8 sheets of prepreg, which is the same as in the conventional example, was sandwiched between molding plates as it was, and the molding pressure was 100 mm and the molding temperature was 16 mm.
A phenol resin laminate having a thickness of 1.6 m was obtained by heating and press molding at 0° C. for 60 minutes.

The 1-method stability and appearance defect rate of the phenolic resin laminates of Examples and Conventional Examples are clearly shown in Table 1. As is clear from Table 1, the J-method stability of the laminate prepared by the method of the present invention is good and the appearance defect rate is low. The authors have praised the superiority of the method for manufacturing laminates.

Table 1 note ＊　1×1m×1× 1 person from special a’t″ Matsuichi Denko Co., Ltd. Representative Patent Attorney Toshimaru Takemoto (2 idiots)

Claims (1)

[Claims] (1) A method for manufacturing a laminate, which comprises impregnating a phenolic resin face into a laminate base material, applying a hexamine solution to the side surface of the laminate made by stacking a required number of dried prepregs, and then applying heat and pressure. .