Patent ID: 8336332

Claim:
A process for producing a glass molded article formed of a phosphate glass containing P 2 O 5 in an amount between 12 to 50 mol %, and optionally at least one oxide selected from WO3, Nb 2 O 5 or TiO 2 , which comprises producing a glass molded article formed of said glass by press molding said glass at a temperature higher than a glass transition temperature in a non-oxidizing atmosphere to reduce one at least one of a W ion, a Nb ion, or a Ti ion in the glass and to thereby produce a colored glass molded article, and then heat- treating said colored glass molded article, wherein a coloring degree of said colored glass molded article after the heat treatment is decreased by employing an oxidizing atmosphere as an atmosphere in which said glass molded article is heat-treated.