PHOTOCURABLE FLUORORESIN COMPOSITION AND PRODUCTION OF VARNISH, PREPREG, AND LAMINATE THEREFROM

摘要

PURPOSE:To obtain the subject composition which is solid at ordinary temp., melts at a specific temp. to have a melt viscosity not higher than a specific value, and upon curing, gives an insulating resin having a low dielectric constant and excellent heat resistance and flame retardancy by incorporating a photopolymerization initiator into a specific fluoropolymer. CONSTITUTION:A photopolymerization initiator (e.g. benzophenone) is incorporated into a fluoropolymer represented by the formula (wherein R<1> and R<2> each is H, F, CH3, or CF3, R<3> and R<3> each is CH2 or CF2, and (x) and (y) each is 0-4) (e.g. homopolymer of hexafluoro-1,3-butadiene) to thereby obtain a photocurable fluororesin composition which is solid at ordinary temp. and melts at 100-200 deg.C to have a melt viscosity of 10<6>P or lower. Curing this composition gives an insulating resin which has a low dielectric constant and is excellent in heat resistance and flame retardancy. A varnish, a prepreg, and a prepreg laminate can be produced from the composition.