PRODUCTION OF NONWOVEN GLASS FIBER CLOTH FOR LAMINATED SHEET AND PRODUCTION OF LAMINATED SHEET

摘要

PURPOSE:To improve the electrical insulation characteristics of a laminated sheet containing a nonwoven glass fiber cloth as a substrate, especially to improve the migration resistance between adjacent through-holes in the case of using the laminated sheet as an insulation substrate of a printed circuit board. CONSTITUTION:A prescribed amount of a solvent is added to a trifunctional epoxy resin, a bifunctional epoxy resin and triethylenetetramine and the components are reacted with each other by thoroughly stirring the mixture for a prescribed period. A binder is produced by adding an aqueous solution of acetic acid and a phenylaminosilane-type coupling agent to the reaction product. The binder is used for the mutual bonding of glass fibers to produce a nonwoven glass fiber cloth. A prescribed amount of an epoxy resin is impregnated in the nonwoven glass fiber cloth and dried to obtain a prepreg. A prescribed number of the prepreg sheets are stacked one upon another and hot- pressed for 1hr under a pressure of 20kgf/cm<2> to obtain a laminated sheet having a thickness of 1.2mm.