Patent ID: 8021752

Claim:
An epoxy resin composition for carbon-fiber-reinforced composite materials, comprising the following components [A], [B], [C], [D] and [E]: [A] epoxy resin, [B] amine curing agent which is dicyandiamide, [C] phosphorus compound, [D] curing accelerator which is 1,1′-(4- methyl-m-phenylene)bis(3,3-dimethylurea) and, [E] thermoplastic resin; wherein component [C] is present in an amount such that the resin composition has a phosphorus atom concentration of 0.2 to 15% by weight; and wherein components [A], [B], [C], [D], and [E] are present in amounts such that the combined amount of components [A], [B], [C], [D], and [E] is at least 95% by weight, based on the overall resin composition.