Patent ID: 6843940
Filing Date: 2005-01-18
Classification: B29C,B29D,Y10S

Abstract:
1. A method for making an organic glass lens or lens blank comprising: providing a two-piece mold defining a molding cavity having a vertical axis which is part of a fixed reference system comprising said vertical axis and a horizontal axis which intersects at the center of the mold, a liquid tight annular closure member disposed at the periphery of the mold pieces for maintaining the two mold pieces and closing the molding cavity; filling the molding cavity from the bottom thereof with a liquid polymerizable composition; evacuating outwardly the gas initially contained in the molding cavity; polymerizing the liquid polymerizing composition; and disassembling the mold and recovering the molded lens or lens blank; wherein the annular closure member comprises at the top of the molding cavity at least a portion made of a material that is initially gas permeable but becomes gas impermeable when contacted by the liquid polymerizable composition.