Process for graft polymerization on surfaces of preformed substates to modify surface properties

• US 5,805,264 A
• Filed: 01/26/1994
• Issued: 09/08/1998
• Est. Priority Date: 06/09/1992
• Status: Expired due to Fees

• Current Assignee: CIBA Vision Corporation (Bayer AG)
• Original Assignee: CIBA Vision Corporation (Bayer AG)
• Inventors: Nomura, Glenn S., Auten, Richard D., Shank, Thomas E., Ajello, Ellen M., Janssen, Robert A.
• Primary Examiner(s): GULAKOWSKI, RANDY P
• Application Number:
  US08/187,776
• Time in Patent Office: 1,686 Days
• Field of Search: 525/479, 525/937, 523/106, 523/108, 351/160 R, 351/166
• US Class Current: 351/160.00R
• CPC Class Codes: C08F 290/12 Polymers provided for in subclasses C08C or C08F
• CPC Class Codes: C08F 290/14 Polymers provided for in subclass C08G
• CPC Class Codes: G02B 1/043 Contact lenses
• CPC Class Codes: Y10S 525/937 Utility as body contact e.g. implant, contact lens or I.U.D.

Abstract

The invention relates to a process for modifying the surface characteristics of a preformed polymer substrate to impart altered properties thereto by graft polymerization on the substrate which includes: placing the polymer substrate in a plasma to form free radicals on the substrate; contacting the substrate having free radicals with oxygen to form hydroperoxy groups on the surface of the substrate; and graft polymerizing an ethylenically unsaturated monomer onto the surface of the polymer substrate.

Claims

1. A process for modifying the surface characteristics of a preformed ophthalmic lens to impart altered properties thereto by graft polymerization on said lens which comprises:

placing the lens in a plasma to form free radicals on the lens contacting the lens having free radicals with oxygen to form hydroperoxy groups on the surface of the lens; and

graft polymerizing an ethylenically unsaturated oligomer or polymer onto the surface of the lens in the presence of a cross-linking agent.

2. The process according to claim 1, wherein the plasma is a noble gas in plasma form.

3. The process according to claim 1, wherein the graft polymerization step is carried out in the presence of a variable valence metal ion to suppress homoploymerization during grafting of the ethylencially unsaturated oligomer or polymer.

4. The process according to claim 1, wherein said oxygen is diatomic oxygen.

5. The process according to claim 2, wherein the plasma is argon in plasma form.

6. The process according to claim 2, wherein the plasma is helium in plasma form.

7. The process of claim 1, further comprising the step of dying the substrate subsequent to said graft polymerizing.

8. The process of claim 7, wherein the dye is covalently bonded to the grafted substrate.

9. A contact lens produced according to the process of claim 1.

10. The process of claim 1, wherein the cross-linking agent is selected from the group consisting of diethylenically unsaturated monomers and polyethylenically unsaturated monomers.

11. The process of claim 10, wherein the cross-linking agent is selected from the group consisting of acrylates, methacrylates, acrylamides, and methacrylamides.

12. The process of claim 11, wherein the cross-linking agent is methylene-bis acrylamide.

13. A process as recited in claim 1, wherein said oligomer or polymer has a molecular weight between about 200 and 100,000.

15. A process as recited in claim 13, wherein said oligomer or polymer is hydrophilic and includes a group selected from the group consisting of polyethylene glycol, polypropylene glycol, poly(ethylene-propylene) glycol, poly(hydroxyethyl methacrylate), poly(dimethyl acrylamide), poly(acrylic acid), poly(methacrylic acid), polysulfone, poly(vinyl alcohol), polyacrylamide, poly(acrylamide-acrylic acid), poly(styrene sulfonate) sodium salt, polyethylene oxide, poly(ethylene oxide-propylene oxide), poly(glycolic acid), poly(lactic acid), poly(vinylpyrrolidone), cellulosics, polysaccharides, mixtures thereof, and copolymers thereof.

16. A process as recited in claim 13, wherein said oligomer or polymer is hydrophobic and includes a group selected from the group consisting of polyethylene, polypropylene, poly(methyl methacrylate), poly(ethyl methacrylate), poly(glycidyl methacrylate), mixtures thereof, and copolymers thereof.

14. A process as recited in claim, wherein said oligomer or polymer has a molecular weight of about 500 to 5000.

17. A contact lens which has been surface treated by a process comprising:

(a) placing the contact lens in a plasma to form free radicals on the contact lens;

(b) contacting the contact lens having free radicals with oxygen to form hydroperoxy groups on the surface of the contact lens; and

(c) graft polymerizing an ethylenically unsaturated oligomer or polymer onto the surface of the contact lens in the presence of a cross-linking agent.

18. A process for modifying the surface characteristics of an ophthalmic lens to impart altered properties thereto by graft polymerization on said lens, which process comprises the steps of:

(a) placing the lens in a plasma to form free radicals on the lens;

(b) contacting the lens having free radicals with oxygen to form hydroperoxy groups on the surface of the lens; and

(c) graft polymerizing an ethylenically unsaturated oligomer or polymer, in the presence of a cross-linking agent, onto the surface of the lens, said oligomer or polymer having a molecular weight between about 200 and 100,000.

19. A process as recited in claim 18, wherein said oligomeric or polymeric chain has a molecular weight of about 500 to 5000.

20. A process as recited in claim 18, wherein said oligomer or polymer is hydrophilic and includes a group selected from the group consisting of polyethylene glycol, polypropylene glycol, poly(ethylene-propylene) glycol, poly(hydroxyethyl methacrylate), poly(dimethyl acrylamide), poly(acrylic acid), poly(methacrylic acid), polysulfone, poly(vinyl alcohol), polyacrylamide, poly(acrylamide-acrylic acid), poly(styrene sulfonate) sodium salt, polyethylene oxide, poly(ethylene oxide-propylene oxide), poly(glycolic acid), poly(lactic acid), poly(vinylpyrrolidone), cellulosics, polysaccharides, mixtures thereof, and copolymers thereof.

21. A process as recited in claim 18, wherein said oligomer or polymer is hydrophobic and includes a group selected from the group consisting of polyethylene, polypropylene, poly(methyl methacrylate), poly(ethyl methacrylate), poly(glycidyl methacrylate), mixtures thereof, and copolymers thereof.

22. A process as recited in claim 18, wherein said graft polymerization is accomplished in the presence of a crosslinking agent.

23. A process as recited in claim 18, wherein said step of graft polymerizing involves the graft polymerizing of at least two different monomers.

24. A process as recited in claim 23, wherein one monomer imparts improved hydrophilic properties to the lens and another monomer imparts improved biocompatibility to the lens.

25. A process as recited in claim 23, wherein one monomer imparts improved hydrophilic properties to the lens and another monomer imparts improved antimicrobial properties to the lens.

26. A process as recited in claim 18, wherein said monomer is polyfunctional.