Abstract: A thermoset resin composition comprises a compound (A) having one or more maleimido groups in its molecule and at least one vinylbenzyl ether compound (B) selected from the group consisting of compounds (B.sub.1) having at least two vinylbenzyl ether groups bonded to a naphthalene nucleus in its molecule and compounds (B.sub.2) having at least two vinylbenzyl ether groups bonded to a benzene nucleus having at least one substituent selected from the group consisting of hydroxyl groups, alkyl groups and alkoxy groups in its molecule.The composition exhibits excellent low-temperature curing properties, heat resistance and mechanical strength.

Abstract: A curable composition for a fiber-reinforced resin, comprises (A) 60-90 weight % of an epoxy-containing (meth)acrylate resin which contains an epoxy group and an unsaturated-monobasic acid ester group in its molecules and which is formed by the reaction of an epoxy resin containing at least two epoxy groups per molecule and having an epoxy equivalent of 100-1000 with an unsaturated-monobasic acid in an amount such that there are 0.2-0.7 equivalents of carboxyl groups per 1 equivalent of epoxy groups, (B) 40-10 weight % of a radical polymerizable monomer, (C) an organic peroxide, (D) a curing agent for the epoxy resin, and (E) one or more reinforcing materials selected from continuous fiber and fiber cloth.