Ultraviolet curable outer coatings for optical fiber.

摘要

Buffer-coated and topcoated optical glass fiber is disclosed in which the topcoat has the high strength and high tensile modulus combined with good elongation and water resistance associated with extruded jacket coatings, but which is applied by ordinary coating procedures and cured by exposure to ultraviolet radiation. The coating compositions which enable this to be achieved comprise 30% to about 80% of linear diacrylate-functional polyurethanes which are the linear polyurethane reaction product of polycarbonate diol with organic diisocyanate in molar proportions providing an average of at least about 2 urethane linkages per molecule, these linear polyurethanes being end-capped with acrylate groups, and these polyurethanes being used in combination with at least 15% of liquid monoethylenically unsaturated monomer having a glass transition temperature above about 55°C.