MANUFACTURE OF LAMINATED SHEET

摘要

PURPOSE:To improve productivity of the titled laminated sheet which is superior in physical properties and not feared that a thin spot is generated, by a method wherein varnish is cured by laminating, heating and pressurizing the same after obtaining of a resin impregnated base material under specific terms by making use of the varnish having resin whose content of impurity is low as its main ingredient. CONSTITUTION:It is desirable to make use of woven cloth constituted of an organic fiber or an inorganic fiber as a material of a beltlike base material. A resin impregnated base material is formed by impregnating the base material supplied continuously with varnish having resin whose content of impurity is low for its main ingredient. Thermosetting resin which is used normally for this use such as polyimide resin or epoxy resin can be mentioned as the resin which becomes a main ingredient of the varnish. The base material is impregnated with resin by making use of the varnish so as to become that an unimpregnated part of the resin impregnated base material is less than 0.3% of the total area of the base material and the number of foams to be contained is less than 500 pieces per 1 in<2>. After a metallic foil and mold release film have been piled up on the surface at need by pilling up the predetermined number of sheets of the resin impregnated base materials formed in this manner, a laminated sheet is obtained by curing the resin by heating and pressurizing them continuously.