Method for coating articles by mold transfer

• US 7,879,267 B2
• Filed: 08/02/2001
• Issued: 02/01/2011
• Est. Priority Date: 08/02/2001
• Status: Active Grant

• Current Assignee: Johnson & Johnson Vision Care Incorporated (Johnson & Johnson)
• Original Assignee: J&J Vision Care Incorporated
• Inventors: Dubey, Dharmesh K., McCabe, Kevin P., Copper, Lenora C., Longo, Jeffery S., Molock, Frank F., Gourd, Dominic, Lin, Xiaoping, Wagner, Andrew J, Adams, Jonathan P., Mahadevan, Shivkumar, Turner, David C.
• Primary Examiner(s): WOLLSCHLAGER, JEFFREY MICHAEL
• Application Number:
  US09/921,192
• Publication Number:
  US 20030052424A1
• Time in Patent Office: 3,470 Days
• Field of Search: None
• US Class Current: 264/1.7
• CPC Class Codes: B29C 37/0032 the coating being applied upon the mould surface before introducing the moulding compound, e.g. applying a gelcoat B29C44/14 and B29C44/32 take precedence
• CPC Class Codes: B29C 39/08 Introducing the material into the mould by centrifugal force
• 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 11/00471 made by rotational casting B29D11/00115 takes precedence
• CPC Class Codes: B29K 2105/0002 monomers or prepolymers
• CPC Class Codes: B29K 2995/0092 hydrophilic
• CPC Class Codes: B29L 2011/0041 Contact lenses
• CPC Class Codes: C08F 2/46 Polymerisation initiated by wave energy or particle radiation

Abstract

A method for coating hydrogel and silicone hydrogel articles, and articles made by the method, are provided in which the coating is first applied to the molding surface in which an article-forming material will be cured to form the article. The method permits the thickness and uniformity of the coating to be more easily controlled than in known coating methods.

Claims

1. A method for manufacturing an article comprising the steps of:

a.) coating a molding surface of a mold or a mold half with a coating effective amount of a high molecular weight coating composition having a molecular weight of greater than about 300 kD and comprising at least one polymer selected from the group consisting of poly(vinyl alcohol), polyethylene oxide, poly(2-hydroxyethyl methacrylate), poly(acrylic acid), poly(methacrylic acid), poly(maleic acid), poly(itaconic acid), poly(acrylamide), poly(dimethylacrylamide), carboxymethylated polymers, polystyrene sulfonic acid, polysulfonate polymers, polysaccharides, glucose amino glycans, block or random copolymers thereof, or mixtures thereof;

b.) dispensing a monomer mixture comprising, a silicone-containing hydrogel monomer, into the mold or mold half; and

c.) curing the monomer mixture and the coating composition using a dwell time of less than about 45 seconds and under conditions suitable to form an article coated with the coating composition;

wherein said at least one polymer does not chemically attach to the article.

2. The method of claim 1, wherein the article is a contact lens.

3. The method of claim 1 or 2, wherein the monomer mixture further comprises at least one hydrogel monomer.

4. The method of claim 1, wherein the coating composition further comprises a low boiling point solvent and a high boiling point solvent.

5. The method of claim 4, wherein the coating of the molding surface is carried out by spin coating.

6. The method of claim 5, wherein spin coating is carried out using at least about 2 μ

l and no more than about 20 μ

l of the coating composition.

7. The method of claim 6, further comprising applying, subsequent to the spin coating step, a pressurized air jet to an edge of the mold.

8. The method of claim 1 wherein the coating composition has a viscosity of about 17.7 cP at 25°

C.

9. The method of claim 1 wherein the coating composition has a viscosity of at least about 4 cP at 25°

C.

10. The method of claim 1 wherein the coating composition has a viscosity of greater than about 1 cP at 25°

C.

11. The method of claim 4 wherein the low boiling point solvent comprises ethanol and the high boiling point solvent comprises ethyl lactate.

12. The method of claim 4 wherein the low boiling point solvent has a boiling point of less than about 90°

C.

13. The method of claim 4 wherein the low boiling point solvent comprises ethanol.

14. The method of claim 4 wherein the low boiling point solvent is selected from the group consisting of n-methyl pyrrolidone, acetone, chloroform, methanol, ethanol, isopropanol, tert-butanol and combinations thereof.

15. The method of claim 4 wherein the high boiling point has a boiling point of greater than about 100°

C.

16. The method of claim 4 wherein the high boiling point solvent comprises ethyl lactate.

17. The method of claim 4 wherein the high boiling point solvent is selected from the group consisting of methyl lactate, ethyl lactate, isopropyl lactate, ethylene glycol, polyethylene glycol, propylene glycol, dimethyl formamide, tetrahydrogeraniol, 1-butanol, 1-pentanol, 1-hexanol, 1-octanol, 3-methyl-3-pentanol, dimethyl-3-octanol, 3-methoxy-1-butanol, 1,2-butanediol, 1,4-butanediol, 1,3-hexanediol, water and combinations thereof.

18. The method of claim 4 wherein the low boiling point solvent and the high boiling point solvent are present at a ratio of about 1:

1.

19. The method of claim 11 wherein the low boiling point solvent and the high boiling point solvent are present at a ratio of about 1:

1.

20. A method for manufacturing an article comprising:

a.) coating a molding surface of a mold or a mold half with a coating effective amount of a high molecular weight hydrophilic coating composition having a molecular weight of greater than about 300 kD and comprising poly(2-hydroxyethyl methacrylate).;

b.) dispensing a monomer mixture comprising a hydrogel monomer, silicone-containing hydrogel monomer, or combination thereof into the mold or mold half; and

c.) curing the monomer mixture and coating composition using a dwell time of less than about 45 seconds and under conditions suitable to form an article coated with the coating composition wherein said coating composition does not chemically attach to the article.

21. The method of claim 20, wherein the article is a contact lens.

22. The method of claim 21, wherein the monomer mixture comprises a hydrogel monomer.

23. The method of claim 21, wherein the monomer mixture comprises a silicone hydrogel monomer.

24. The method of claim 23, wherein the silicone hydrogel monomer mixture comprises a reaction product of a silicone based macromer Group Transfer Polymerization product and a polymerizable mixture comprising Si_8-10 monomethacryloxy terminated polydimethyl siloxane, polydimethylsiloxane other than Si_8-10 monomethacryloxy terminated polydimethyl siloxane, and a hydrophilic monomer.

25. The method of claim 24, wherein the silicone hydrogel monomer mixture comprises the macromer in an amount of about 15 to about 25 wt percent, the Si_8-10 monomethacryloxy terminated polydimethyl siloxane in an amount of about 20 to about 30 wt percent;

methacryloxypropyl tris(trimethyl siloxy) silane in an amount of about 15 to about 25 wt percent;

N,N-dimethyl acrylamide in an amount of about 20 to about 30 wt percent;

2-hydroxy ethyl methacrylate in an amount of about 2 to about 7 wt percent;

tetraethyleneglycol dimethacrylate in an amount of about 0 to about 5 wt percent and poly(N-vinyl pyrrolidinone) in an amount of about 0 to about 5 weight percent.

26. The method of claim 21, wherein the coating composition further comprises a low boiling point solvent and a high boiling point solvent.

27. The method of claim 26, wherein the coating of the molding surface is carried out by spin coating.

28. The method of claim 27, wherein spin coating is carried out using at least about 2 μ

l and no more than about 20 μ

l of the coating composition.

29. The method of claim 28, further comprising applying, subsequent to the spin coating step, a pressurized air jet to an edge of the mold.

30. The method of claim 20 wherein the coating composition has a viscosity of about 17.7 cP at 25°

C.

31. The method of claim 20 wherein the coating composition has a viscosity of at least about 4 cP at 25°

C.

32. The method of claim 20 wherein the coating composition has a viscosity of greater than about 1 cP at 25°

C.

33. The method of claim 26 wherein the low boiling point solvent comprises ethanol and the high boiling point solvent comprises ethyl lactate.

34. The method of claim 26 wherein the low boiling point solvent has a boiling point of less than about 90°

C.

35. The method of claim 26 wherein the low boiling point solvent comprises ethanol.

36. The method of claim 26 wherein the low boiling point solvent is selected from the group consisting of n-methyl pyrrolidone, acetone, chloroform, methanol, ethanol, isopropanol, tert-butanol and combinations thereof.

37. The method of claim 26 wherein the high boiling point has a boiling point of greater than about 100°

C.

38. The method of claim 26 wherein the high boiling point solvent comprises ethyl lactate.

39. The method of claim 26 wherein the high boiling point solvent is selected from the group consisting of methyl lactate, ethyl lactate, isopropyl lactate, ethylene glycol, polyethylene glycol, propylene glycol, dimethyl formamide, tetrahydrogeraniol, 1-butanol, 1-pentaol, 1-hexanol, 1-octanol, 3-methyl-3-pentanol, dimethyl-3-octanol, 3-methoxy-1-butanol, 1,2-butanediol, 1,4-butanediol, 1,3-hexanediol, water and combinations thereof.

40. The method of claim 26 wherein the low boiling point solvent and the high boiling point solvent are present at a ratio of about 1:

1.

41. The method of claim 33 wherein the low boiling point solvent and the high boiling point solvent are present at a ratio of about 1:

1.

42. A method for manufacturing contact lenses comprising:

a.) coating a molding surface of a mold or a mold half with a coating effective amount of a hydrophilic coating composition having a molecular weight of greater than about 300 kD;

b.) dispensing a mixture comprising a silicone-containing hydrogel monomer into the mold or mold half; and

c.) curing the mixture and coating composition using a dwell time of less than about 45 seconds and under conditions suitable to form a contact lens coated with the coating composition, wherein the formed lens exhibits physiological compatibility and said coating composition does not chemically attach to the article.

43. The method of claim 42, wherein the mixture further comprises at least one hydrogel monomer.

44. The method of claim 42, wherein the silicone hydrogel monomer mixture comprises a reaction product of a silicone based macromer Group Transfer Polymerization product and a polymerizable mixture comprising Si_8-10 monomethacryloxy terminated polydimethyl siloxane, polydimethylsiloxane other than Si_8-10 monomethacryloxy terminated polydimethyl siloxane, and a hydrophilic monomer.

45. The method of claim 44, wherein the silicone hydrogel monomer mixture comprises the macromer an amount of about 15 to about 25 wt percent, the Si_8-10 monomethacryloxy terminated polydimethyl siloxane in an amount of about 20 to about 30 wt percent;

methacryloxypropyl tris(trimethyl siloxy) silane in an amount of about 15 to about 25 wt percent;

N,N-dimethyl acrylamide in an amount of about 20 to about 30 wt percent;

2-hydroxy ethyl methacrylate in an amount of about 2 to about 7 wt percent;

tetraethyleneglycol dimethacrylate in an amount of about 0 to about 5 wt percent and poly(N-vinyl pyrrolidinone) in an amount of about 0 to about 5 weight percent.

46. The method of claim 42, 43, 44, or 45, wherein the coating composition comprises poly(vinyl alcohol), polyethylene oxide, poly(2-hydroxyethyl methacrylate), poly(acrylic acid), poly(methacrylic acid), poly(maleic acid), poly(itaconic acid), poly(acrylamide), poly(dimethacrylamide), carboxymethylated polymers, polystyrene sulfonic acid, polysulfonate polymers, polysaccharides, glucose amino glycans, block or random copolymers thereof, or mixtures thereof.

47. The method of claim 46, wherein the coating composition comprises poly(2-hydroxyethyl methacrylate).

48. The method of claim 46, wherein the coating composition further comprises a low boiling point solvent and a high boiling point solvent.

49. The method of claim 48, wherein the coating of the molding surface is carried out by spin coating.

50. The method of claim 49, wherein spin coating is carried out using at least about 2 μ

l and no more than about 20 μ

l of the coating composition.

51. The method of claim 50, further comprising applying, subsequent to the spin coating step, a pressurized air jet to an edge of the mold.

52. The method of claim 42 wherein the coating composition has a viscosity of about 17.7 cP at 25°

C.

53. The method of claim 42 wherein the coating composition has a viscosity of at least about 4 cP at 25°

C.

54. The method of claim 42 wherein the coating composition has a viscosity of greater than about 1 cP at 25°

C.

55. The method of claim 48 wherein the low boiling point solvent comprises ethanol and the high boiling point solvent comprises ethyl lactate.

56. The method of claim 48 wherein the low boiling point solvent has a boiling point of less than about 90°

C.

57. The method of claim 48 wherein the low boiling point solvent comprises ethanol.

58. The method of claim 48 wherein the low boiling point solvent is selected from the group consisting of n-methyl pyrrolidone, acetone, chloroform, methanol, ethanol, isopropanol, tert-butanol and combinations thereof.

59. The method of claim 48 wherein the high boiling point has a boiling point of greater than about 100°

C.

60. The method of claim 48 wherein the high boiling point solvent comprises ethyl lactate.

61. The method of claim 48 wherein the high boiling point solvent is selected from the group consisting of methyl lactate, ethyl lactate, isopropyl lactate, ethylene glycol, polyethylene glycol, propylene glycol, dimethyl formamide, tetrahydrogeraniol, 1-butanol, 1-pentanol, 1-hexanol, 1-octanol, 3-methyl-3-pentanol, dimethyl-3-octanol, 3-methoxy-1-butanol, 1,2-butanediol, 1,4-butanediol, 1,3-hexanediol, water and combinations thereof.

62. The method of claim 48 wherein the low boiling point solvent and the high boiling point solvent are present at a ratio of about 1:

1.

63. The method of claim 55 wherein the low boiling point solvent and the high boiling point solvent are present at a ratio of about 1:

1.