Resin film, useful per se or as laminated circuit board for insulation in electrical technology and electronics, is based on epoxy resin, hardener, thermoplastic resin and filler in lower concentration near surface than in center

摘要

Resin film comprises (A) an epoxy resin with 2 or more glycidyl groups/molecule, (B) an epoxy resin hardener, (C) a thermoplastic resin and (D) a filler, such that the filler content is one or both surface zones in the cross-section of the film is less than that in the central zone. An independent claim is also included for a laminated circuit board with an insulating layer obtained by hardening the resin film.