abstract |
An epoxy resin composition containing an epoxy resin [A 1 ], epoxy resin [B 1 ], epoxy resin [C 1 ] and curing agent [D] wherein [A 1 ] is a bisphenol-type epoxy resin with a softening point of 90° C. or more, [B 1 ] is a tri- or higher functional amine-type epoxy resin, [C 1 ] is a bisphenol F-type epoxy resin with a number average molecular weight of 450 or less, and the epoxy resins [A 1 ] to [C 1 ] satisfy the following contents per 100 parts by mass of total epoxy resin content: [A 1 ] 20 to 50 parts by mass, [B 1 ] 30 to 50 parts by mass and [C 1 ] 10 to 40 parts. The present invention provides low-viscosity epoxy resin compositions that are excellent in impregnating reinforcing fibers and capable of producing cured resins with excellent modulus and toughness, as well as prepregs and fiber-reinforced composite materials based on those epoxy resin compositions. |