METHOD FOR PRODUCING OPHTHALMIC LENSES

摘要

The invention provides a method for producing ophthalmic lenses, preferably contact lenses, more preferably silicone hydrogel contact lenses. This method involves applying a coat of catanionic vesicles onto the molding surfaces of a mold. By having a coat of catanionic vesicles on the molding surfaces of a mold, mold separation force and lens defects generated during mold opening and de-molding process can be substantially reduced.

主权项

1. A method for making contact lenses, comprising the steps of:
(1) obtaining a fluid lens-forming composition and a mold, wherein the fluid lens-forming composition comprises at least one member selected from the group consisting of a hydrophilic vinylic monomer, a silicone containing vinylic monomer, a silicone-containing crosslinker, a silicone-containing prepolymer, a hydrophilic prepolymer free of silicone, and combinations thereof, wherein the mold has a first mold half with a first molding surface defining the anterior surface of a contact lens and a second mold half with a second molding surface defining the posterior surface of the ophthalmic lens, wherein said first and second mold halves are configured to receive each other such that a cavity is formed between said first and second molding surfaces; (2) applying a coating of an aqueous catanionic solution containing a cationic surfactant and an anionic surfactant onto the first molding surface and/or the second molding surface, wherein the weight percentage ratio of the anionic surfactant over the cationic surfactant in the aqueous solution is from about 0.1 to about 10; (3) drying the coating of the aqueous catanionic solution to form a coat of catanionic vesicles on the first and/or second molding surface, wherein the formation of the coat of the catanionic vesicles on the first and/or second molding surfaces is characterized by having a percentage of reduction in mold separation force of at least about 50% relative to a control mold without any coat of catanionic vesicles thereon and optionally by having at most about 5 star-tears per lens on average, when being used in cast molding of ophthalmic lenses from the fluid lens-forming composition; (4) introducing the fluid lens-forming composition into the cavity formed by the first and second molding surfaces with the coat of the catanionic vesicles formed in step (3) thereon; (5) actinically irradiating the fluid lens-forming composition in the cavity to form the ophthalmic lens; and (6) opening the mold and removing the formed ophthalmic lens from the mold.