Patent ID: 9738782
Date: 2017-08-22
CPC Classifications: C08G,C08J,C08L

Claim:
1. An epoxy resin composition containing an epoxy resin [A1], epoxy resin [B1], epoxy resin [C1] and curing agent [D], wherein [A1] is a bisphenol F-type epoxy resin with a softening point of 108° C. to 135° C., [B1] is a tri- or higher functional amine-type epoxy resin, [C1] is a bisphenol F-type epoxy resin with a number average molecular weight of 450 or less, wherein the epoxy resins [A1] to [C1] satisfy the following contents per 100 parts by mass of total epoxy resin content: [A1] 30 to 50 parts by mass, [B1] 30 to 50 parts by mass and [C1] 10 to 40 parts by mass, and wherein a cured resin obtained by curing the epoxy resin composition has a phase separation structure involving an [A1]-rich phase and a [B1]-rich phase with a phase separation structural period of 1 nm to 5 μm.