MANUFACTURE OF VARNISH IMPREGNATED WEBS AND LAMINATE BOARDS MADE THEREFROM

摘要

A process for manufacturing a prepreg for use in the manufacture of laminates and printed circuit boards comprising the steps of treating a reinforcement substrate 12, such as a woven fiberglass fabric, with a resin-free solvent that can include one or more solvent 18 compounds to effectively wet the reinforcement substrate, optionally, air drying 24 the treated reinforcement substrate, thereafter, impregnating the fabric reinforcement with a curable varnish 32 and heating the varnish-impregnated reinforcement to partially cure the varnish. The void-free prepregs made according to the invention are subsequently laminated with copper or other conductive foils and then pressed into multilayer laminate boards. Alternatively, the void-free perpregs made according to the invention are used as bonding plies for multiple printed circuit boards and pressed into laminates with or without copper or other conductive foils.