Epoxy resin composition, prepreg, and fiber-reinforced composite material

Abstract

The present invention provides an epoxy resin composition that serves to produce a cured epoxy resin that simultaneously realizes a high heat resistance, a high elastic modulus, and a low color and to produce a molded article having a good appearance without suffering the formation of white spots on the surface thereof when used as matrix resin in a fiber reinforced composite material. It provides an epoxy resin composition that includes an epoxy resin as component [A] and an imidazole compound as component [B] and meets the undermentioned conditions (a) to (d): (a) it contains an isocyanurate type epoxy resin [A1] as component [A] in an amount of 10 to 40 parts by mass relative to the total quantity of epoxy resins which represents 100 parts by mass, (b) it contains a bisphenol type epoxy resin [A2] as a component [A] in an amount of 40 to 90 parts by mass relative to the total quantity of epoxy resins which represents 100 parts by mass, (c) resin [A2] has an average epoxy equivalent weight of 220 to 500 g/eq, and (d) the content of component [B] is such that the ratio of the number of imidazole groups to the total number of epoxy groups in the epoxy resins is 0.01 to 0.06.

Dependencies are inferred from the claim text.