Liquid radiation-curable coating compositions and optical glass fibers coated therewith

Claim 2

A liquid radiation-curable coating composition adapted to deposit, after radiation curing, an adherent cured coating on a glass surface, comprising a radiation-curable polyetylenic polymeric organic compound, and from about 0.5 % to about 5% of the coating composition of a polyalkoxy silane containing an organic substituent which carries a single mercaptyl hydrogen atom which is capable of reacting with ethylenic unsaturation by Michael adduction.

Claim 3

A coating composition as recited in claim 1 in which said radiation-curable polymeric organic compound is acrylate-functional.

Claim 4

A coating composition as recited in claim 2 in which said radiation-curable acrylate-functional polymeric organic compound is a polyurethane or a polyurethane urea.

Claim 5

A coating composition as recited in claim 1 in which said composition cures to provide a film having a tensile modulus less than abnout 103 000 N/cm 2 .

Claim 6

A coating composition as recited in claim 1 in which said composition cures to provide a film having a tensile modulus less than about 6900 N/cm 2 .

Claim 7

A coating composition as recited in claim 1 in which said radiation-curable polyethylenic organic compound is acrylate-functional, and a photoinitiator is present to render said composition curable with ultraviolet radiation.

Claim 8

An optical glass fiber having its glass surface adherently coated with an ultraviolet-cured coating of a liquid ultraviolet-curable coating composition adapted to deposit, after said ultraviolet cure, an adherent cured coating on a glass surface, said composition comprising an ultraviolet-curable polymeric polyacrylate, a photoinitiator to render said composition curable with ultraviolet light, and from about 0.5% to about 5% of the coating composition of a polyalkoxy silane containing an organic substituent carrying a single mercaptyl hydrogen atom capable of reacting with acrylate unsaturation by Michael adduction.

Claim 9

An optical glass fiber having its glass surface adherently coated with an ultraviolet-cured coating of a liquid ultraviolet-curable coating composition adapted to deposit, after said ultraviolet cure, an adherent cured coating on a glass surface, said composition comprising an ultraviolet-curable polymeric polyacrylate, a photoinitiator to render said composition curable with ultraviolet light, and from about 0.5% to about 5% of the coating composition of a polyalkoxy silane containing an organic substituent carrying a single mercaptyl hydrogen atom capable of reacting with acrylate unsaturation by Michael adduction.