Epoxy resin composition and the epoxy resin varnish using the same, bonding sheet, a coverlay film

摘要

PROBLEM TO BE SOLVED: To provide an epoxy resin composition excellent in flexibility and flame retardancy, and to provide an epoxy resin varnish, a bonding sheet and a cover-lay film using the composition.SOLUTION: The epoxy resin composition comprises (a) an epoxy resin, (b) a curing agent and (c) a phenolic hydroxy group-containing aromatic polyamide-polybutadiene-acrylonitrile copolymer. In the composition: the (a) component is a trishydroxyphenylmethane type epoxy resin; the (b) component is composed of 10(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide only; phenolic hydroxy groups in the (b) component are included by 0.5 mol or more with respect to 1.0 mol of epoxy groups in the (a) component; and the compounding rate of the (c) component is 5 to 300 pts.mass with respect to 100 pts.mass of the total of the (a) component and the (b) component.