Photochromic contact lenses and methods for their production

• US 20050258408A1
• Filed: 04/08/2005
• Published: 11/24/2005
• Est. Priority Date: 12/20/2001
• Status: Abandoned Application

• Current Assignee: Frank F. Molock, Gina M. Cullerton, Shivkumar Mahadevan, Terry L. Spaulding
• Original Assignee: Frank F. Molock, Gina M. Cullerton, Shivkumar Mahadevan, Terry L. Spaulding
• Inventors: Molock, Frank F., Mahadevan, Shivkumar, Spaulding, Terry L., Cullerton, Gina M.
• Application Number:
  US11/102,320
• Publication Number:
  US 20050258408A1
• Time in Patent Office: Days
• US Class Current: 252/586
• CPC Class Codes: B29D 11/00125 Auxiliary operations, e.g. removing oxygen from the mould, conveying moulds from a storage to the production line in an inert atmosphere
• CPC Class Codes: B29D 11/00317 Production of lenses with markings or patterns
• CPC Class Codes: B29D 11/00903 on the surface
• CPC Class Codes: C08L 33/10 Homopolymers or copolymers of methacrylic acid esters
• CPC Class Codes: G02B 1/04 made of organic materials, e.g. plastics G02B1/08 takes precedence
• CPC Class Codes: G02B 1/043 Contact lenses
• CPC Class Codes: G02B 5/23 Photochromic filters
• CPC Class Codes: G02C 7/04 Contact lenses for the eyes disinfection or sterilisation of contact lenses A61L12/00
• CPC Class Codes: G02C 7/102 Photochromic filters

Abstract

The invention provides a photochromic composition for use in tinting contact lenses in which the binding polymer used is capable of forming an interpenetrating polymer network with the lens material. When the photochromic compositions of the invention are applied to uncured lens material that is subsequently cured, the binding polymer forms an interpenetrating polymer network with the lens material embedding the photochromic compound within the lens material resulting in a stable, photochromic lens.

Claims

1. A photochromic composition for use in tinting contact lenses, the photochromic composition comprising one or more photochromic compound, one or more solvents, and a binding polymer, wherein the binding polymer is capable of forming an interpenetrating polymer network with a lens material.

2. The photochromic composition of claim 1, wherein the interpenetrating polymer network formed is a semi-interpenetrating polymer network.

3. The photochromic composition of claim 1, wherein the interpenetrating polymer network formed is a sequential-interpenetrating polymer network.

4. The photochromic composition of claim 1, wherein the binding polymer comprises a molecular weight, M_peak, of about 7,000 to about 40,000.

5. The photochromic composition of claim 1, wherein the binding polymer comprises:

CH₃(CH₂)_x-L-COCHR═

CH₂

wherein L is —

NH or oxygen, x is a whole number from 2 to 24, R is a C₁ to C₆ alkyl or hydrogen.

6. The photochromic composition of claim 1, wherein the binding polymer comprises a copolymer of methacrylic acid, 2-hydroxyethyl methacrylate, and lauryl methacrylate.

7. The photochromic composition of claim 1, wherein the binding polymer comprises a copolymer of 2-hydroxyethyl methacrylate and methacrylic acid.

8. The photochromic composition of claim 1, wherein the binding polymer comprises a homopolymer of 2-hydroxyethyl methacrylate.

9. The photochromic composition of claim 1, 2, 3, 4, 6, 7 or 8, wherein the one or more solvents comprises at least one medium boiling point solvents and one low boiling point solvent.

10. The photochromic composition of claim 1, 2, 3, 4, 6, 7 or 8, wherein the surface tension is ≦

28 dynes/cm.

11. The photochromic composition of claim 6, 7 or 8 wherein the medium boiling point solvents comprise 1-ethoxy-2-propanol and isopropyl lactate.

12. The photochromic composition of claim 1, 2, 3, 4, 6, 7 or 8, further comprising at least one additional component selected from the group consisting of plasticizers, pigments, opacifying agents and mixtures therof.

13. The photochromic composition of claim 12, comprising about 0.2 to about 25 weight percent of the one or more pigments, about 30 to about 45 weight percent of the binding polymer, about 40 to about 70 weight percent of the one or more solvents, about 0 to about 25 weight percent of the opacifying agent, and about 0.2 to about 7 weight percent of the plasticizer.

14. A photochromic composition for use in tinting contact lenses, the photochromic composition comprising one or more photochromic compound, one or more solvents, and a binding polymer having a molecular weight, M_peak, of about 7,000 to about 40,000, wherein the binding polymer is capable of forming an interpenetrating polymer network with a lens material comprising a HEMA-based hydrogel or a silicone-based hydrogel.

15. The photochromic composition of claim 14, wherein the interpenetrating polymer network formed between the binding polymer and the lens material is a semi-interpenetrating polymer network

16. The photochromic composition of claim 14, wherein the interpenetrating polymer network formed between the binding polymer and the lens material is a sequential interpenetrating polymer network

17. The photochromic composition of claim 14, wherein the binding polymer comprises a copolymer of methacrylic acid, 2-hydroxyethyl methacrylate, and lauryl methacrylate.

18. The photochromic composition of claim 14, wherein the binding polymer comprises a copolymer of methacrylic acid and 2-hydroxyethyl methacrylate.

19. The photochromic composition of claim 14, wherein the binding polymer comprises a homopolymer of 2-hydroxyethyl methacrylate.

20. The photochromic composition of claims 14-19, wherein the one or more solvents comprises two medium boiling point solvents and one low boiling point solvent.

21. The photochromic composition of claim 20, wherein the two medium boiling point solvents comprise 1-ethoxy-2-propanol and isopropyl lactate.

22. The photochromic composition of claims 14-19 further comprising a plasticizer and at least one pigment.

23. The photochromic composition of claim 22, comprising about 0.2 to about 25 weight percent of the one or more pigments, about 30 to about 45 weight percent of the binding polymer, about 40 to about 70 weight percent of the one or more solvents, about, and about 0.2 to about 7 weight percent of the plasticizer.

40. The ophthalmic lens derived from the photochromic composition of claim 23, the method of claim 30 and the mold of claim 39.

24. A method for manufacturing a photochromic contact lens comprising the steps of:

a.) applying to a molding surface of a mold a tinting-effective amount of a photochromic composition comprising one or more photochromic compounds, one or more solvents and at least one binding polymer;

b.) dispensing a lens-forming amount of a lens material into the mold;

c.) swelling the photochromic composition in the lens material; and

d.) curing the lens material in the mold to form the tinted contact lens, wherein the binding polymer and the lens material form an interpenetrating polymer network.

25. The method of claim 24, wherein the binding polymer has a molecular weight, M_peak, of about 7,000 to about 40,000 and the lens material comprises HEMA based hydrogels or silicone-based hydrogels.

26. The method of claim 24, wherein the binding polymer comprises a copolymer of methacrylic acid, 2-hydroxyethyl methacrylate, and lauryl methacrylate.

27. The method of claim 24, wherein the binding polymer comprises a copolymer of methacrylic acid and 2-hydroxyethyl methacrylate.

28. The method of claim 24, wherein the binding polymer comprises a homopolymer of 2-hydroxyethyl methacrylate.

29. The method of claim 24 or 25, wherein the one or more solvents comprises two medium boiling point solvents and one low boiling point solvent.

30. The method of claim 29, wherein the two medium boiling point solvents comprise 1-ethoxy-2-propanol and isopropyl lactate.

41. The method of claim 24 wherein said photochromic compound is coated or wetted with said binding polymer.

31. A mold for use in manufacturing a tinted contact lens comprising a first and second mold half, wherein at least one molding surface of the first and second mold halves comprises a layer on at least a part of said molding surface comprising, one or more photochromic compounds, one or more solvents, and a binding polymer, wherein the binding polymer is capable of forming an interpenetrating polymer network with a lens material.

32. The mold of claim 31, wherein the interpenetrating polymer network formed between the binding polymer and the lens material is a semi-interpenetrating polymer network.

33. The mold of claim 31, wherein the interpenetrating polymer network formed between the binding polymer and the lens material is a sequential interpenetrating polymer network.

34. The mold of claim 31, wherein the binding polymer has a molecular weight, M_peak, of about 7,000 to about 40,000.

35. The mold of claim 31, wherein the binding polymer comprises a copolymer of methacrylic acid, 2-hydroxyethyl methacrylate, and lauryl methacrylate.

36. The mold of claim 31, wherein the binding polymer comprises a copolymer of methacrylic acid and 2-hydroxyethyl methacrylate.

37. The mold of claim 31, wherein the binding polymer comprises a homopolymer of 2-hydroxyethyl methacrylate.

38. The mold of claim 31-37 wherein the one or more solvents comprises two medium boiling point solvents and one low boiling point solvent.

39. The mold of claim 38, wherein the two medium boiling point solvents comprise 1-ethoxy-2-propanol and isopropyl lactate.