Process and composition for cladding optical fibers

• US 5,492,987 A
• Filed: 06/02/1995
• Issued: 02/20/1996
• Est. Priority Date: 06/24/1991
• Status: Expired due to Term

• Current Assignee: Yama Capital, LLC
• Original Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Inventors: Minns, Richard A.
• Primary Examiner(s): Chapman, Mark
• Application Number:
  US08/460,230
• Time in Patent Office: 263 Days
• Field of Search: 526/242, 526/245, 522/35, 522/42
• US Class Current: 526/245
• CPC Class Codes: C08F 220/22 Esters containing halogen
• CPC Class Codes: C08L 33/14 of esters containing halogen, nitrogen, sulfur, or oxygen atoms in addition to the carboxy oxygen
• CPC Class Codes: G02B 1/048 characterised by the cladding material
• CPC Class Codes: Y10S 522/904 Monomer or polymer contains initiating group
• CPC Class Codes: Y10S 522/905 Benzophenone group

Abstract

In a process for cladding an optical fiber, a photoinitiator monomer having both a photoinitiating group and an ethylenically unsaturated group is reacted with a fluorosubstituted monomer having an ethylenically unsaturated group, thereby preparing a copolymer having pendant photoinitiating groups. This copolymer is then mixed with a fluorosubstituted diacrylate, thereby forming a photopolymerizable composition, which is coated on to the optical fiber and exposed to ultraviolet light, thereby curing the photopolymerizable composition to produce a cladding on the optical fiber. Preferred claddings can have refractive indices below 1.35.

Claims

1. A process for the preparation of a copolymer having pendant photoinitiating groups, this process comprising reacting a photoinitiator monomer having both a photoinitiating group and an ethylenically unsaturated group with a fluorosubstituted monomer having an ethylenically unsaturated group.

2. A process according to claim 1 wherein the fluorosubstituted monomer comprises a monoacrylate or mono-methacrylate.

3. A process according to claim 1 wherein the ethylenically unsaturated group of the photoinitiator monomer is an acrylate or methacrylate group.

4. A copolymer having pendant photoinitiating groups, this copolymer having repeating units from a photoinitiator monomer having both a photoinitiating group and an ethylenically unsaturated group, and repeating units from a fluorosubstituted monomer having an ethylenically unsaturated group.

5. A copolymer according to claim 4 wherein the fluorosubstituted monomer comprises a monoacrylate or mono-methacrylate.

6. A copolymer according to claim 5 wherein the fluorosubstituted monoacrylate comprises a fluorosubstituted polyether.

7. A copolymer according to claim 6 wherein the fluorosubstituted monoacrylate comprises ##STR5##

8. A copolymer according to claim 4 wherein the ethylenically unsaturated group of the photoinitiator monomer is an acrylate or methacrylate group.

9. A copolymer according to claim 8 wherein the photoinitiator monomer comprises an acrylate of a phenoxyalkanol or of a phenylalkanol.

10. A copolymer according to claim 9 wherein the photoinitiator monomer comprises ##STR6##