PROCESS FOR MELTING AND REFINING SILICA-BASED GLASS

摘要

A process for making silica-based glass includes; (a) forming a glass precursor melt that includes glass network formers and glass network modifiers, the glass precursor melt being at a temperature in the range of 900C to I700C and heaving a viscosity of not more than 30 Pa-s, and (b) refining the glass precursor melt. Either or both steps (a) (b) can include stirring and/or be carried out under reduced pressure to enhance refining. The refined glass precursor melt preferably is mixed with additional materials including silica (SiO2) to form a silica-based glass melt.