Abstract: A coating composition curable by active energy rays which composition can form an transparent inorganic cured film having an excellent appearance, a mar resistance, and film adhesion properties is provided. The coating composition contains a siloxane compound (A) obtainable by the hydrolysis and condensation of an alkyl silicate expressed by the following general formula (1) wherein R1, R2, R3, and R4 represent an alkyl group having 1 to 5 carbon atoms or an acyl group having 2 to 4 carbon atoms, respectively, and n indicates an integer from 3 to 20, and a cation polymerization initiator (B) having a sensitivity to the active energy rays. A method for forming a protective film by applying the coating composition on the surface of a plastic substrate and then irradiating the composition with active energy rays to form the protective film is also provided.

Abstract: In a lens sheet, a lens portion (3) made of activation energy curing resin such as ultraviolet curing resin has a plurality of lens units, the lens portion (3) is disposed on at least one side of a transparent substrate (2) such as plastic sheet, a relaxation layer (1) is disposed between the transparent substrate (2) and the lens portion (3), and the thickness of the relaxation layer (1) is within a range of 1% to 30% of the height (H) of the lens units. The relaxation layer (1) is made of activation energy curing resin and formed integrally with the lens portion (3). The refractive index of the transparent substrate (2) is lower than that of the lens portion (3). The lens units are elongated prisms each having a substantially triangular cross section. The thickness of the relaxation layer is within a range of 1 ?m to 10 ?m, for example. The prisms have the vertical angle of 50° to 75° and are arranged with a pitch of 10 ?m to 150 ?m.

Abstract: In a lens sheet, a lens portion (3) made of activation energy curing resin such as ultraviolet curing resin has a plurality of lens units, the lens portion (3) is disposed on at least one side of a transparent substrate (2) such as plastic sheet, a relaxation layer (1) is disposed between the transparent substrate (2) and the lens portion (3), and the thickness of the relaxation layer (1) is within a range of 1% to 30% of the height (H) of the lens units. The relaxation layer (1) is made of activation energy curing resin and formed integrally with the lens portion (3). The refractive index of the transparent substrate (2) is lower than that of the lens portion (3). The lens units are elongated prisms each having a substantially triangular cross section. The thickness of the relaxation layer is within a range of 1 &mgr;m to 10 &mgr;m, for example. The prisms have the vertical angle of 50° to 75° and are arranged with a pitch of 10 &mgr;m to 150 &mgr;m.

Abstract: In a lens sheet, a lens portion made if activation energy curing resin such as ultraviolet curing resin has a plurality of lens units, the lens portion is disposed on at least one side of a transparent substrate such as plastic sheet, a relaxation layer is disposed between the transparent substrate and the lens portion, and the thickness of the relaxation layer is within a range of 1% to 30% of the height of the lens units. The relaxation layer is made of activation energy curing resin and formed integrally with the lens portion. The refractive index of the transparent substrate is lower than that of the lens portion. The lens units are elongated prisms each having a substantially triangular cross section.

Abstract: Disclosed herein is a polybutylene glycol dimethacrylate which provides various kinds of plastics having good flexibility and low water absorption. Disclosed also herein is a resin composition for cast polymerization which provides molded products which have high heat resistance, good flexibility, and low water absorption, without sacrificing impact resistance and surface hardness. They will find use as optical materials, lenses, etc.

Abstract: Disclosed is a composition comprising(A) 10 to 60 parts by weight of a polybutylene glycol di(meth)acrylate represented by the general formula (I): ##STR1## (B) 20 to 80 parts by weight of a specific urethane poly(meth)acrylate or epoxy poly(meth)acrylate,(C) 5 to 60 parts by weight of a specific mono(meth)acrylate, and(D) 0 to 60 parts by weight of a compound having at least one polymerizable double bond in the molecule,with the total amount of components (A), (B), (C) and (D) being 100 parts by weight. This composition is suitable for the making of plastic lenses because of its excellent properties such as high thermal resistance, high impact resistance, good dyeability, low water absorption and high surface accuracy.

Abstract: Disclosed is a membranous gas separator comprising (a) a porous substrate having an average pore diameter of not greater than 100 .ANG. and (b) a .pi.-electron conjugated conducting polymer retained within at least a part of the pores of the porous substrate in such a way that the pores are not blocked characterized in that retaining the .pi. -electron conjugated conducting polymer within the pore is carried out by a chemical oxidative polymerization.

Abstract: Disclosed is a process for preparing a membranous gas separator comprising (a) a porous substrate having an average pore diameter of not greater than 100 .ANG. and (b) a .pi.-electron conjugated conducting polymer retained within at least a part of the pores of the porous substrate in such a way that the pores are not blocked, characterized in that retaining the .pi.-electron conjugated conducting polymer within the pore is carried out by a chemical oxidative polymerization.