Method for producing contact lenses

摘要

The invention provides an improved process in which minimal force is required to separate mold halves so as to minimize lens damages resulted from the forced separation of mold halves. The process of the invention comprises: providing a mold including a first mold half having a first molding surface and a second mold half having a second molding surface, wherein the first and second mold halves are configured to receive each other such that a mold cavity is formed between the first and second molding surfaces, wherein one of the first and second mold halves has a collar that encircles the other mold half to provide a seal between the two mold halves when the mold is closed; dispensing a specific amount of a polymerizable lens-forming material into one of the mold halves; mating the mold halves to close the mold; polymerizing said polymerizable material located between the two mold halves, thereby forming a molded contact lens; applying a small force to the collar to distort the collar, thereby breaking the seal between the two mold halves; and opening the mold.