Coating material for optical communication glass fibers

Claim 2

A coating material for optical communication glass fibers, comprising the following components (a), (b) and (c): (a) a vinyl group terminated methylphenylpolysiloxane having a viscosity at 25° C. of 100 to 15,000 cP and with a methyl/phenyl molar ratio in the range of 1/1 to 10/1, the amount of the component (a) being 100 parts by weight, (b) at least one organohydrogenpolysiloxane selected from the group consisting of a methylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP and containing at least three silicon atom bonded hydrogen atoms in one molecule, and a methylphenylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP, containing at least three silicon atom bonded hydrogen atoms in one molecule and with a methyl/phenyl molar ratio not smaller than 1/1, the amount of the component (b) being an amount by weight required to provide a molar ratio of the silicon atom bonded hydrogen atoms in the component (b) to the silicon atom bonded vinyl groups in the component (a) of 0.8/1 to 10/1, and (c) platinum or a platinum compound, the amount by weight of the component (c) being 0.5 to 1,000 ppm in terms of platinum metal based on the total amount of the components (a) and (b).

Claim 3

The coating material for optical communication glass fibers as defined in claim 1, in which said organohydrogenpolysiloxane of the component (b) is a methylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP and containing at least three silicon atom bonded hydrogen atoms in one molecule.

Claim 4

The coating material for optical communication glass fibers as defined in claim 1, in which said organohydrogenpolysiloxane of the component (b) is a methylphenylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP, containing at least three silicon atom bonded hydrogen atoms in one molecule and with a methyl/phenyl ratio in the range of 1/1 to 100/1.

Claim 5

The coating material for optical communication glass fibers as defined in claim 1, 2 or 3, in which the methyl/phenyl molar ratio in the vinyl group terminated methylphenylpolysiloxane of the component (a) and the methyl/phenyl molar ratio in the methylphenylhydrogenpolysiloxane of the component (b) are of about and equal value.

Claim 6

The coating material for optical communication glass fibers as defined in claim 1, 2 or 3, in which said vinyl group terminated methylphenylpolysiloxane of the component (a) has a viscosity at 25° C. of 500 to 10,000 cP and a methyl/phenyl molar ratio in the range of 1/1 to 7/1, said organohydrogenpolysiloxane contains 3 to 30 silicon atom bonded hydrogen atoms per molecule, and said platinum or platinum compound of the component (c) being used in an amount of 1 to 200 ppm in terms of platinum metal based on the total amount of the components (a) and (b).

Claim 7

An optical communication glass fiber having a primary coat layer formed by applying a composition onto said glass fiber followed by curing, said composition comprising: (a) a vinyl group terminated methylphenylpolysiloxane having a viscosity at 25° C. of 100 to 15,000 cP and with a methyl/phenyl molar ratio in the range of 1/1 to 10/1, the amount of the component (a) being 100 parts by weight, (b) at least one organohydrogenpolysiloxane selected from a methylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP and containing at least three silicon atom bonded hydrogen atoms in one molecule, and a methylphenylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP, containing at least three silicon atom bonded hydrogen atoms in one molecule and with a methyl/phenyl molar ratio not smaller than 1/1, the amount of the component (b) being an amount by weight required to provide a molar ratio of the silicon atom bonded hydrogen atoms in the component (b) to the silicon atom bonded vinyl groups in the component (a) of 0.8/1 to 10/1, and (c) platinum or a platinum compound, the amount by weight of the component (c) being 0.5 to 1,000 ppm in terms of platinum metal based on the total amount of the components (a) and (b).

Claim 8

An optical communication glass fiber having a primary coat layer formed by applying a composition onto said glass fiber followed by curing, said composition comprising: (a) a vinyl group terminated methylphenylpolysiloxane having a viscosity at 25° C. of 100 to 15,000 cP and with a methyl/phenyl molar ratio in the range of 1/1 to 10/1, the amount of the component (a) being 100 parts by weight, (b) at least one organohydrogenpolysiloxane selected from a methylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP and containing at least three silicon atom bonded hydrogen atoms in one molecule, and a methylphenylhydrogenpolysiloxane having a viscosity at 25° C. of 0.7 to 5,000 cP, containing at least three silicon atom bonded hydrogen atoms in one molecule and with a methyl/phenyl molar ratio not smaller than 1/1, the amount of the component (b) being an amount by weight required to provide a molar ratio of the silicon atom bonded hydrogen atoms in the component (b) to the silicon atom bonded vinyl groups in the component (a) of 0.8/1 to 10/1, and (c) platinum or a platinum compound, the amount by weight of the component (c) being 0.5 to 1,000 ppm in terms of platinum metal based on the total amount of the components (a) and (b).