Surface-treatment of silicone medical devices comprising an intermediate carbon coating and graft polymerization

• US 6,200,626 B1
• Filed: 05/20/1999
• Issued: 03/13/2001
• Est. Priority Date: 05/20/1999
• Status: Expired due to Term

• Current Assignee: Bausch & Lomb Incorporated (Bausch Health Cos., Inc.)
• Original Assignee: Bausch & Lomb Incorporated (Bausch Health Cos., Inc.)
• Inventors: McGee, Joseph A., Grobe, George L. III, Valint, Paul L. Jr., Ammon, Daniel M. Jr.
• Primary Examiner(s): Beck, Shrive
• Assistant Examiner(s): MICHENER, JENNIFER KOLB
• Application Number:
  US09/315,912
• Time in Patent Office: 663 Days
• Field of Search: 427/2.24, 427/2.1, 427/488, 427/534, 427/535, 427/539, 427/164, 427/299, 427/393.5
• US Class Current: 427/2.24
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/34 Macromolecular materials
• CPC Class Codes: A61L 27/52 Hydrogels or hydrocolloids
• CPC Class Codes: C08J 2383/04 Polysiloxanes
• CPC Class Codes: C08J 7/0423 with at least one layer of inorganic material and at least one layer of a composition containing a polymer binder
• CPC Class Codes: C08J 7/043 Improving the adhesiveness of the coatings per se, e.g. forming primers adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50
• CPC Class Codes: C08J 7/046 Forming abrasion-resistant coatings; Forming surface-hardening coatings
• CPC Class Codes: C08J 7/056 Forming hydrophilic coatings
• CPC Class Codes: C08J 7/16 with polymerisable compounds
• CPC Class Codes: C08L 33/02 Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• CPC Class Codes: C08L 33/14 of esters containing halogen, nitrogen, sulfur, or oxygen atoms in addition to the carboxy oxygen
• CPC Class Codes: C08L 33/26 Homopolymers or copolymers of acrylamide or methacrylamide
• CPC Class Codes: C08L 39/06 Homopolymers or copolymers of N-vinyl-pyrrolidones
• CPC Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: C08L 83/10 Block- or graft-copolymers containing polysiloxane sequences obtained by polymerising a compound having a carbon-to-carbon double bond on to a polysiloxane C08L51/08, C08L53/00
• CPC Class Codes: G02B 1/043 Contact lenses

Abstract

The present invention provides an optically clear, hydrophilic coating upon the surface of a silicone medical device by sequentially subjecting the surface of the lens to plasma polymerization reaction in a hydrocarbon atmosphere to form a carbon layer, and then graft polymerizinga mixture of monomers comprising hydrophilic monomers onto the carbon layer. The invention is especially useful for forming a biocompatible coating on silicone hydrogel contact lenses.

Claims

1. A method for treating the surface of a silicone medical device comprising the steps of:

(a) subjecting the surface of said silicone medical device to an oxidative plasma treatment;

(b) subjecting the oxidatively plasma treated surface of the silicone medical device to a plasma polymerization reaction in a hydrocarbon atmosphere to foin a carbonaceous polymeric surface on the lens having a thickness of 50 to 500 Angstroms; and

(c) grafting a mixture of polymerizable ethylenically unsaturated monomers comprising hydrophilic monomers onto the carbonaceous polymeric surface by means of a free-radical reaction, thus foiming a biocompatible surface on the medical device.

2. The method of claim 1, wherein the medical device is a silicone contact lens or in intraocular device.

3. The method of claim 1, wherein the medical device is a silicone hydrogel, continuous-wear contact lens.

4. The method of claim 1, wherein the plasma pretreatment comprises oxidation of the surface with an nitrogen or oxygen containing oxidizing gas.

5. The method of claim 4, wherein the plasma pretreatment is conducted at 10 to 1000 watts for a period of 1 to 10 minutes, at a pressure of 0.01 to 1.0 torr.

6. The method of claim 4, wherein the plasma pretreatment is conducted in an oxidizing atmosphere comprising a gas selected from at least one of:

ambient air, oxygen gas, hydrogen peroxide, alcohol, water, and ammonia.

7. The method of claim 1, wherein the plasma polymerization reaction of step (b) is conducted in an atmosphere comprising hydrocarbons having 1 to 10 carbon atoms.

8. The method of claims 7 wherein the hydrocarbons are aliphatic or olefinic and comprise 4 to 8 carbon atoms.

9. The method of claim 8, wherein the hydrocarbons comprise at least one of butane, isobutylene, 1,3-butadiene, and isoprene.

10. The method of claim 1, wherein the hydrophilic monomers are macromonomers.

11. The method of claim 10, wherein the graft polymerization is conducted in the presence of an initiator on the surface of the carbonaceous polymeric surface of step (b).

12. The method of claim 1, wherein the monomer mixture comprises 10 to 100 mole percent of hydrophilic monomers selected from the group consisting of acrylamides, lactams, poly(alkyleneoxy)methacrylates, methacrylic acid or hydroxyalkyl methacrylates.

13. The method of claim 12, wherein the hydrophilic monomers are selected from the group consisting of dimethylacrylamide, acrylamide, hydroxyethyl methacrylate, and N-vinyl pyrrolidinone.

14. The method of claim 1, wherein the mixture of ethylenically unsaturated monomers comprises 0 to 20 mole percent hydrophobic monomers.

15. The method of claim 1, wherein the grafting step (c) comprises dipping the medical device in a solution comprising the mixture of ethylenically unsaturated monomers.

16. A device including a hydrophilic surface, wherein said surface comprises:

(a) a first oxidized layer created by plasma treatment of the surface of the silicone medical device;

(b) a second carbonaceous layer attached to the first oxidized layer (a); and

(c) polymers grafted to the second carbonaceous layer (b) by means of free-radical graft polymerization, wherein said polymers arc derived from a mixture of monomers comprising hydrophilic monomers.

17. The medical device of claim 16, wherein the medical device is a silicone contact lens.

18. The medical device of claim 16, wherein the medical device is a silicone hydrogel continuous-wear lens.

19. The medical device of claim 16, wherein the monomer mixture comprises 10 to 100 mole percent of hydrophilic monomers selected from the group consisting of acrylamides, lactams, poly(alkyleneoxy)methacrylates, methacrylic acid or hydroxyalkyl methacrylates.

20. The medical device of claim 19, wherein the hydrophilic monomers are selected from the group consisting of dimethylacrylamide, acrylamide, hydroxyethyl methacrylate, and N-vinyl pyrrolidinone.

21. The method of claim 19, wherein the monomer mixture comprises 0 to 35 mole percent hydrophobic monomers.