Optical fiber with polymeric coating crosslinked in the presence of both radical and cationic photoinitiators

A method of using a composition to form an optical fiber comprising surrounding a glass portion with at least one coating of crosslinked polymer material, wherein said coating is obtained by crosslinking a composition comprising:

• (a) at least one radically crosslinkable oligomer containing at least two reactive functional groups and having a number average molecular weight lower than about 1,000;
• (b) at least one cationically crosslinkable compound containing at least one reactive functional group,
• wherein the cationically crosslinkable compound is selected from vinyl ether terminated ester compounds having the following general formula:
• wherein:
• n is an integer from 1 to 4 inclusive;
• Y is a mono- di-, tri, or tetra-functional radical having a molecular weight of about 12 to about 500 and is independently selected from the group consisting of alkyl, aryl, arylalkyl, and cycloalkyl radicals;
• X is a divalent radical having a molecular weight of about 25 to about 500, each X being independently selected from the group consisting of alkylene and cycloalkylene radicals;
• and
• R1 R2, are monovalent radicals which are independently selected from the group consisting of hydrogen and alkyl groups having from 1 to 20 carbon atoms;
• (c) at least one free radical photoinitiator;
• and
• (d) at least one cationic photoinitiator.

A method of using a composition to form an optical fiber comprising surrounding a glass portion with at least one coating of crosslinked polymer material, wherein said coating is obtained by crosslinking a composition comprising:

• (a) at least one radically crosslinkable oligomer containing at least two reactive functional groups and having a number average molecular weight lower than about 1,000;
• wherein said at least one radically crosslinkable oligomer is represented by the following formulae:
• R-—Ar-—R or
• R-L-Ar-L-R
• wherein R is a radiation-curable functional group, Ar is an aromatic group containing moiety, and L is a linking group;
• (b) at least one cationically crosslinkable compound containing at least one reactive functional group,
• wherein the cationically crosslinkable compound is selected from vinyl ether terminated ester compounds having the following general formula:
• wherein:
• n is an integer from 1 to 4 inclusive;
• Y is a mono- di-, tri, or tetra-functional radical having a molecular weight of about 12 to about 500 and is independently selected from the group consisting of alkyl, aryl, arylalkyl, and cycloalkyl radicals;
• X is a divalent radical having a molecular weight of about 25 to about 500, each X being independently selected from the group consisting of alkylene and cycloalkylene radicals;
• and
• R1 and R2, are monovalent radicals which are independently selected from the group consisting of hydrogen and alkyl groups having from 1 to 20 carbon atoms;
• (c) at least one free radical photoinitiator;
• and
• (d) at least one cationic photoinitiator.

A method of using a composition to form a ribbon of optical fibers comprising arranged in parallel and enclosing in a common coating of crosslinked polymer material said optical fibers, wherein said common coating being obtained by crosslinking a composition comprising:

• (a) at least one radically crosslinkable oligomer containing at least two reactive functional groups and having a number average molecular weight lower than about 1,100;
• (b) at least one cationically crosslinkable compound containing at least one reactive functional group,
• wherein the cationically crosslinkable compound is selected from vinyl ether terminated ester compounds having the following general formula:
• wherein:
• n is an integer from 1 to 4 inclusive;
• Y is a mono- di-, tri, or tetra-functional radical having a molecular weight of about 12 to about 500 and is independently selected from the group consisting of alkyl, aryl, arylalkyl, and cycloalkyl radicals;
• X is a divalent radical having a molecular weight of about 25 to about 500, each X being independently selected from the group consisting of alkylene and cycloalkylene radicals;
• and
• R1 and R2 are monovalent radicals which are independently selected from the group consisting of hydrogen and alkyl groups having from 1 to 20 carbon atoms;
• (c) at least one free radical photoinitiator;
• and
• (d) at least one cationic photoinitiator.