Abstract: Photocurable liquid coating compositions adapted to provide primary coatings for optical glass fibers are disclosed. These compositions comprise an acrylate-terminated polyurethane, an acrylate of an unsubstituted or C.sub.1 -C.sub.10 alkyl substituted phenol that is alkoxylated with a C.sub.2 -C.sub.4 alkylene oxide and at least one alkylacrylate having a T.sub.g below about -45.degree. C. Films produced from these ultraviolet light curable compositions are flexible and possess good water resistance and good wet adhesion.

Abstract: Photocurable liquid coating compositions adapted to provide primary coatings for optical glass fibers are disclosed. These compositions comprise polycarbonate-based acrylate-terminated polyurethane, an acrylate of an unsubstituted or C.sub.1 -C.sub.10 alkyl substituted phenol that is alkoxylated with a C.sub.2 -C.sub.4 alkylene oxide and at least one alkylacrylate having a T.sub.g below about -45.degree. C. Films produced from these ultraviolet light curable compositions are flexible and possess good water resistance and good wet adhesion.

Abstract: A radiation-curable coating composition adapted for the coating of optical glass fiber, comprising an ethylenically unsaturated polyurethane which is the reaction product of:(A) a polyether diol having a molecular weight in the range of 200 to 8,000 and a structural unit represented by the formula: ##STR1## in which R.sup.1 -R.sup.4 are each independently selected from hydrogen and an alkyl group containing from 1-4 carbon atoms, such as a polymer of copolymer of methyl tetrahydrofuran;(B) a polyisocyanate compound, preferably a diisocyanate; and(C) a polymerizable ethylenically unsaturated compound having a single hydroxy group, such as a monohydric acrylate;there being employed per equivalent of hydroxy in component (C) from 1.1 to 2 equivalents of said polyisocyanate with the balance of the isocyanate groups being reacted waith the hydroxy groups of said diol.

Abstract: An ultraviolet curing liquid coating composition which, when cured with ultraviolet light in the presence of an appropriate photoinitiator, provides a coating adapted for the coating of optical glass fiber. This coating composition comprises as the essential component, an acrylate-terminated polyurethane oligomer based on a polyfunctional core which is at least trifunctional and which supports one branch for each functionality in the core. Each of the branches leads to an acrylate-functional terminal group, with there being from about 150 to about 2500 units of molecular weight in each branch between the trifunctional core and the acrylate-functional terminal group. Depending primarily upon the molecular weight of the branches, one can provide coating compositions for buffer coat, single coat or topcoat use.

Abstract: An ultraviolet-curable coating composition adapted for the buffer coating of optical glass fiber consists essentially of an acrylate-capped polyurethane in admixture with at least about 25% of its weight of liquid monoethylenically unsaturated monomer having a low glass transition temperature below about 0.degree. C. and at least about 3% of N-vinyl pyrrolidone based on the weight of the low glass transition temperature monomer.

Abstract: An ultraviolet-curable coating composition adapted for the buffer coating of optical glass fiber consists essentially of an acrylate-capped polyurethane in admixture with at least about 25% of its weight of liquid monoethylenically unsaturated monomer having a low glass transition temperature below about 0.degree. C. The acrylate-capped polyurethane is based on a generally linear polyurethane which is the reaction product of organic diisocyanate with a stoichiometric deficiency of a modified diol, this modified diol being the diester reaction product of polyoxytetramethylene glycol having a molecular weight of from about 200 to about 2000 with a stoichiometric deficiency of a long chain ester-forming hydrocarbon-substituted dicarboxylic acid or ester-forming substitution product thereof.

Abstract: A postformable ultraviolet curable primer coating composition is disclosed which consists essentially of: (A) from 10% to 80% of a linear acrylate-terminated polyurethane based on a polycarbonate diol; (B) from 2% to 35%, of acrylic acid; (C) from 15% to 65% of a monoethylenically unsaturated monomer having the rapid ultraviolet cure rate associated with acrylate monomers and having a glass transition temperature above 35.degree. C.,; (D) from 0% to 25% of a polyacrylate monomer; and (E) photoinitiator rendering the composition curable with ultraviolet light.

Abstract: An ultraviolet curing liquid coating composition is provided which, when cured with ultraviolet light in the presence of an appropriate photoinitiator, provides a buffer coating for optical glass fiber having adequate strength at room or expected elevated temperature and stability at such elevated temperature, a high index of refraction above 1.48, and a low tensile modulus which remains low to resist microbending difficulties down to around -60.degree. C. This coating composition consists essentially of a linear acrylate-terminated polyurethane oligomer including urea groups introduced by the presence in the oligomer of the reaction product with isocyanate functionality of about 30% to about 90% by weight of the acrylate-terminated oligomer of a polyoxyalkylene diamine having a molecular weight in the range of from about 1000 to about 8000 in which the alkylene group contains from 2-4 carbon atoms.

Abstract: An ultraviolet curing liquid coating composition is disclosed which, when cured with ultraviolet light in the presence of an appropriate photoinitiator, provides buffer coatings for optical glass fiber having adequate strength at room or expected elevated temperature and stability at such elevated temperature, a high index of refraction above 1.48, and a low tensile modulus which remains low to resist microbending difficulties down to around -60.degree. C. This coating composition consists essentially of a linear polyacrylate-terminated polyurethane or polyurea oligomer having a room temperature tensile modulus of at least 100 psi., and a tensile modulus at -60.degree. C. which is less than 175,000 psi., when capped with 2-hydroxyethyl acrylate and cured with ultraviolet light, in admixture with a liquid acrylate-functional material which does not increase the low temperature hardness and which provides the liquidity needed for coating application.