Claims
- 1. In a process for producing an improved hydrophilic, biocompatible contact lens, the improvement comprising:
- (a) reacting together water and a prepolymer to form a hydrated polyurea-polyurethane gel, said prepolymer prepared by:
- (i) selecting diols or polyols, at least 75% of which are oxyethylene-based diols or polyols having molecular weights of about 7000 to about 30,000 and
- (ii) reacting said diols or polyols with polyisocyanate at an isocyanate-to-hydroxyl ratio of about 1.8 to about 2.2 so that essentially all hydroxyl groups of said diols or polyols are capped with polyisocyanate, and
- (b) preparing a hydrated contact lens from said polyurea-polyurethane polymer gel to obtain a lens having a surface which resists nonspecific protein adsorption.
- 2. The method of claim 1 in which said prepolymer is prepared in the presence of an aprotic, water-miscible solvent.
- 3. A method of producing a hydrophilic, biocompatible contact lens characterized by a surface which resists nonspecific protein binding, said method comprising:
- (a) preparing a prepolymer by
- (i) selecting diols or polyols, at least 75% of which are oxyethylene-based diols or polyols having molecular weights of about 7000 to about 30,000 and
- (ii) reacting said diols or polyols with polyisocyanate at an isocyanate-to-hydroxyl ratio of about 1.8 to about 2.2 so that essentially all hydroxyl groups of said diols or polyols are capped with polyisocyanate;
- (b) introducing the prepolymer into a contact lens mold;
- (c) reacting said prepolymer with a crosslinking agent in near stoichiometric amount to produce a polyureapolyurethane polymer molded gel;
- (d) hydrating the molded gel; and
- (e) preparing a hydrated contact lens from said molded gel to obtain a lens having a surface which resists nonspecific protein adsorption.
- 4. The method of claim 3 in which said hydrated contact lens is prepared by:
- (a) machining an individual contact lens blank from said hydrated molded gel; and
- (b) polishing said lens blank to obtain a hydrated contact lens having a surface which resists nonspecific protein adsorption.
- 5. The method of claim 3 in which said prepolymer is prepared in the presence of an aprotic, water-miscible solvent.
- 6. The method of claim 3 in which said crosslinking agent is selected from the group consisting of polyhydric alcohols, polyhydric amines, polyisocyanates and water.
- 7. The method of claim 6 in which said crosslinking agent is water.
- 8. The method of claim 7 in which the gelling and hydrating steps occur simultaneously.
Parent Case Info
This is a divisional application of Ser. No. 312,331, filed Feb. 16, 1989, now U.S. Pat. No. 4,886,866; which is a continuation of Ser. No. 135,878, filed Dec. 21, 1987, now abandoned; which is a continuation-in-part of (1) Ser. No. 932,080, filed Nov. 18, 1986, now abandoned, and (2) copending application having a Ser. No. 409,9071, filed Sept. 18, 1989; which is a continuation-in-part of Ser. No. 300,765, filed Jan. 23, 1989, now abandoned; which is a continuation of Ser. No. 130,826, filed Dec. 9, 1987, now abandoned; which is a continuation-in-part of Ser. No. 932,080, filed Nov. 18, 1986 mentioned above.
US Referenced Citations (19)
Related Publications (1)
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Number |
Date |
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409971 |
Sep 1989 |
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Divisions (1)
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Number |
Date |
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Parent |
312331 |
Feb 1989 |
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Continuations (2)
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Number |
Date |
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Parent |
135878 |
Dec 1987 |
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Parent |
130826 |
Dec 1987 |
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Continuation in Parts (3)
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Number |
Date |
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Parent |
932080 |
Nov 1986 |
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Parent |
300765 |
Jan 1989 |
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Parent |
932080 |
Nov 1986 |
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