HIGH PURITY SYNTHETIC QUARTZ GLASS POWDER, PRODUCTION THEREOF AND HIGH PURITY SYNTHETIC QUARTZ GLASS FORMED BODY USING THE POWDER

摘要

PROBLEM TO BE SOLVED: To obtain a synthetic quartz powder and a quartz glass formed body suppressive in impurity content by supplying silicon alkoxide as a source material and water to a reaction chamber through pipings whose inner walls are treated by a specified method. ;SOLUTION: Silicon alkoxide as a source material and water are supplied through pipings to a reaction chamber to effect hydrolysis to obtain a silica gel, which is calcined to obtain a synthetic quartz glass powder. The inner walls of the pipings are preliminarily subjected to at least one treatment of acid treatment, degreasing treatment and electrolytic polishing. The obtd. synthetic quartz glass powder is fused to produce a synthetic quartz glass formed body. The acid treatment for the inner walls of pipings is performed by treating the inner walls of pipings with an acid component. Degreasing is performed by dissolving and removing oils and fats with a medium which can dissolve fats and oils such as an org. solvent and a neutral detergent.;COPYRIGHT: (C)1997,JPO