PROCESS FOR PRODUCING GLASS COMPOSITION FOR LAMP, GLASS COMPOSITION FOR LAMP, AND LAMP

摘要

A process for producing a glass composition for lamps which includes a melting step in which a raw-material mixture containing an oxide of a given element and a hydroxide of the given element in an oxide/hydroxide proportion of from 1/3 to 1 by mole is melted and brought into a vitreous state. In the melting step, the raw-material mixture is heated so that the hydroxide undergoes a decomposition reaction to generate a gas comprising at least either of H<SUB>2</SUB>O and H<SUB>2</SUB>. Thus, a glass reduced in bubble inclusions can be produced without generating any harmful gas.