THERMOSETTING RESIN COMPOSITION, ADHESIVE SHEET, METALLIC FOIL WITH ADHESIVE AND MULTILAYERED PRINTED WIRING BOARD

摘要

PROBLEM TO BE SOLVED: To provide a printed wiring board having a low relative permittivity and a low dielectric dissipation factor of an insulating bonding layer. SOLUTION: This thermosetting resin composition consists essentially of (a) a linear epoxy polymer prepared by polymerizing a bifunctional epoxy resin with bifunctional phenols at 1/(0.9-1.1) equiv. ratio of the epoxy groups/phenolic hydroxyl groups, (b) a polyfunctional epoxy resin and (c) an adduct of phenols to a conjugated diene-based polymer. The thermosetting resin composition is used to form an insulating bonding layer of a surface conductor layer to an inner layer circuit board of a printed wiring board.