Abstract: Provided is a prepreg including: a urethane (meth)acrylate that is a reaction product of a polyisocyanate compound comprising a polymethylene polyphenyl polyisocyanate as an essential component with a hydroxyl group-containing compound comprising, as an essential component, a compound having a hydroxyl group and a (meth)acryloyl group; a polymerization initiator; and carbon fibers. The prepreg is excellent in workability and molding property and can form molded products excellent in various physical properties such as interlayer shear strength and heat resistance. Thus, the prepreg is suitable for use in various molded articles including automotive members.

Abstract: Provided is a prepreg including: a urethane (meth)acrylate that is a reaction product of a polyisocyanate compound comprising a polymethylene polyphenyl polyisocyanate as an essential component with a hydroxyl group-containing compound comprising, as an essential component, a compound having a hydroxyl group and a (meth)acryloyl group; a polymerization initiator; and carbon fibers. The prepreg is excellent in workability and molding property and can form molded products excellent in various physical properties such as interlayer shear strength and heat resistance. Thus, the prepreg is suitable for use in various molded articles including automotive members.

Abstract: There is disclosed an optical fiber core wire binder, comprising (A) a radical-polymerizable oligomer, (B) a radical-polymerizable monomer, (C) a photopolymerization initiator, and at least one compound selected from the group consisting of (D) modified silicone compounds and (E) nitrogen/sulfur atom-containing compounds, with the content of the compound selected from the group consisting of the components (D) and (E) being 0.01 to 20% by weight of the total of the components (A) to (E), and with the surface tension being 30 &mgr;N/m or less at 23° C. The optical fiber core wire binder can restrain bubbles from being involved or remaining when optical fiber core wires are being twisted while it is filled and applied around them, and it can form a cured product (solid material) that is excellent in workability and adhesion to a tension member.

Abstract: There is disclosed an optical fiber core wire binder, comprising (A) a radical-polymerizable oligomer, (B) a radical-polymerizable monomer, (C) a photopolymerization initiator, and at least one compound selected from the group consisting of (D) modified silicone compounds and (E) nitrogen/sulfur atom-containing compounds, with the content of the compound selected from the group consisting of the components (D) and (E) being 0.01 to 20% by weight of the total of the components (A) to (E), and with the surface tension being 30 &mgr;N/m or less at 23° C. The optical fiber core wire binder can restrain bubbles from being involved or remaining when optical fiber core wires are being twisted while it is filled and applied around them, and it can form a cured product (solid material) that is excellent in workability and adhesion to a tension member.