Abstract: A lens sheet comprising a transparent substrate and a lens portion composed of a cured product of an ultraviolet-curable resin composition, which is formed on at least one surface of the transparent substrate. The resin composition exhibits a polymerization shrinkage at curing of not larger than 20% as calculated based on the difference of the specific gravity at 25.degree. C., and a modulus of elasticity at 25.degree. C. after curing of 10 to 1,000 kg/cm.sup.2. The ultraviolet-curable resin composition is preferably comprised of a polyvalent (meth)acrylate, a mono(meth)acrylate and a photopolymerization initiator.

Abstract: An actinic ray curable composition for casting polymerization which comprises:(A) 40-90 parts by weight of an urethane poly(meth)acrylate having at least two (meth)acryloyl groups in one molecule,(B) 10-60 parts by weight of a radical polymerizable vinyl monomer having a boiling point of 100.degree. C. or higher, and(C) 0.005-5 parts by weight, per 100 parts by weight of total of the above components (A) and (B), of at least one member selected from methylphenyl glyoxylate, 2-hydroxy-2-methyl-1-phenylpropane-1-one, hydroxycyclohexyl phenyl ketone and a photo-initiator represented by the general formula (I): ##STR1## (wherein R.sub.1 and R.sub.2 which may be identical or different each represents a phenyl group, a methoxy group, an ethoxy group or an isopropyloxy group) and a casting polymerization molded product obtained by radical polymerization of said composition by irradiation with actinic ray.

Abstract: A method for the fabrication of an optical fiber sheet, which comprises supplying a number of optical fibers, arranging them in a plane so that they do not intersect one another, holding the optical fibers by a tool having a clearance slightly larger than the size of the fibers, constringing the fibers in the held portion in the lateral direction to bring them close to one another so that the fibers are contacted with one another, and applying an adhesive to the contacted portion of the fibers and solidifying the adhesive to fix the fibers in the sheet-like form, an apparatus for carrying out the method and an optical fiber sheet prepared according to the method.

Abstract: An ultraviolet curable ink composition comprising, as main components,(A) a polyurethane poly(meth)acrylate obtained by reacting a polyisocyanate compound of the formula: ##STR1## wherein R.sub.1 is a hydrogen atom or a methyl group, and n is an integer of from 1 to 20, with a hydroxyl group-containing (meth)acrylate, and having, in one molecule, at least two (meth)acryloyl groups and at least two urethane bonds,(B) a radical polymerizable low molecular weight compound, and(C) a photopolymerization initiator.

Abstract: A process for forming a coating film comprising coating, onto a substrate, a solvent type coating material prepared by blending a color pigment or combination of a metallic powder and a color pigment into base resin (A) containing a carboxylic acid amide copolymer as main component, then coating a transparent thermosetting powder coating material thereon, and thereafter heating and curing them.