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Use of surfactants in extraction procedures for silicone hydrogel ophthalmic lenses

  • US 7,968,018 B2
  • Filed: 04/18/2007
  • Issued: 06/28/2011
  • Est. Priority Date: 04/18/2007
  • Status: Active Grant
First Claim
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1. A method of producing a silicone hydrogel ophthalmic lens, comprising:

  • polymerizing a polymerizable silicone hydrogel lens forming composition in an ophthalmic lens mold assembly to produce a polymerized silicone hydrogel lens product;

    removing the polymerized silicone hydrogel lens product from a concave lens-defining surface and a convex lens-defining surface of the mold assembly to produce a demolded and delensed ophthalmic lens product;

    prior to contacting the demolded and delensed lens product with any liquid, placing the demolded and delensed ophthalmic lens product in a lens carrier that has physical features on its surface which the lens product can contact;

    extracting materials from the delensed ophthalmic lens product by contacting the demolded and delensed ophthalmic lens product with a liquid composition that comprises alcohol, water, and a surfactant;

    subsequently contacting the demolded and delensed ophthalmic lens product with water to produce a hydrated silicone hydrogel ophthalmic lens;

    wherein the physical features comprise openings or holes located within pockets or recesses; and

    wherein the resulting ophthalmic lens product has no surface distortion or has less surface distortion as compared to a substantially identical resulting ophthalmic lens product produced from a substantially identical demolded and delensed ophthalmic lens product by a substantially identical process but without the surfactant present in the liquid composition.

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