Patent ID: 6033765
Filing Date: 2000-03-07
Classification: B32B,C08J,H05K,Y10S,Y10T

Abstract:
A printed circuit substrate comprising at least one insulating layer and at least one conductive layer;said insulating layer is a prepreg comprising a porous para-oriented aromatic polyamide film impregnated with a thermoplastic resin and/or a thermosetting resin, wherein the porous para-oriented aromatic polyamide film is composed of para-aramid fibrils having a diameter of not more than 1 .mu.m, with the fibrils planarly arranged as a network or a non-woven fabric and laminated in layer form, and the film has a linear thermal expansion coefficient at 200.degree. C. to 300.degree. C. of .+-.50.times.10.sup.-6 /.degree.C. and has 30 to 95% of vacant spaces.