Patent ID: 9050761
Filing Date: 2015-06-09
Classification: B29D

Abstract:
1. A method of forming a contact lens, which comprises dosing a metered amount of a contact lens forming material including a volatile solvent into a mold cavity enclosed by a male mold half with a second molding surface and a female mold half with a first molding surface of the contact lens mold, the mold cavity in a closed state of the contact lens mold corresponding to the shape of the contact lens to be manufactured, wherein the contact lens forming material is subsequently polymerized and/or cross-linked to form a contact lens, and wherein dosing of the contact lens forming material into the mold cavity is accomplished while the male and female mold halves are associated with each other substantially gas-tight to prevent evaporation of the solvent; and wherein the mold cavity is connected with a dosing channel, which is accessible from the outside of the contact lens mold and wherein dosing of the lens forming material is accomplished through this dosing channel, the dosing channel extending through a guide sleeve which holds the male and female mold halves; and further wherein during the dosing of the contact lens forming material, air contained in the mold cavity is expelled through at least one venting opening which is provided in the guide sleeve, and which venting opening is connected with the mold cavity by an annular channel which is from about 5 μm to about 15 μm wide.