Abstract: A liquid curable resin composition containing urethane bond at a concentration of 2.0.times.10.sup.-3 mole/gm or more and comprising:(a) a urethane (meth)acrylate having at least three cyclic structures in the molecule;(b) a polymerizable mono-functional vinyl monomer of which the homopolymer has a glass transition point of 50.degree. C. or more; and(c) a polymerization initiator.The liquid curable resin composition possesses a high Young's modulus, exhibits very little contraction stress, has high tenacity and good curing characteristics. Along with these superior characteristics, the high reliability of the composition makes it a suitable coating material for optical fiber. Furthermore, since the resin composition possesses a high Young's modulus and high tenacity, it is also useful as a protective coating material for metals, plastics, wood, ceramics, glass, and the like.

Abstract: Provided is an optical fiber having a primary coating thereon wherein the coating is formulated from an ultra-violet light curable resin composition containing:(A) a polyether polyol compound containing, as structural units, groups represented by the following formulas (1), (2, and (3),(1) --CH.sub.2 CH.sub.2 O--(2) --CH.sub.2 CH(R)O--, and(3) one or more groups selected from groups (a), (b), and (c) below, ##STR1## wherein R represents an alkyl group containing two or more carbon atoms, and R.sup.1 and R.sup.2 are independently selected from a hydrogen atom or a methyl group;(B) a polyisocyanate compound; and(C) a (meth)acrylate compound having a hydroxy group.

Abstract: A curable liquid resin composition comprising a urethane (meth)acrylate polymer obtained by reacting:(A) a polyol compound containing as structural units groups which are represented by formulae--CH.sub.2 CH.sub.2 O-- or--CH.sub.2 CH(CH.sub.2 CH.sub.3)O--;(B) a polyisocyanate compound; and(C) at least one (meth)acrylate compound containing a hydroxyl group and coated articles produced therefrom.

Abstract: A liquid photocurable plastic composition is disclosed which comprises:(a) from 14% to 70% by weight of a polyurethane (meth)acrylate having a polyoxyalkylene structure in the backbone of the polyurethane, said polyurethane (meth)acrylate containing 0.8 to 8 weight percent of ethylenic unsaturation, from 50% to 98% by weight of the polyoxyalkylene structure, and having a number average molecular weight of 1,000 to 7,000;(b) from 5% to 40% by weight of a polyurethane (meth)acrylate having at least 15% by weight of a tricyclodecane structure in the backbone of the polyurethane and a number average molecular weight of from 500 to 1,000;(c) a reactive diluent; and(d) a polymerization initiator.

Abstract: A curable resin composition adapted for bundling coated optical fibers comprises:(A) polyetherpolyurethanes of at least one kind having an ethylenically unsaturated group and containing from 40% to 85%, by weight, of a tetramethyleneoxy structure in the entire structure thereof;(B) ethylenically unsaturated monomer; and(C) a photopolymerization initiator. This resin composition, when cured, has a coefficient of dynamic friction with polyethylene of not more than 0.4, and is thus specially adapted for use in holding together coated optical fibers in a tape-like structure.