CRYSTALLINE SYNTHETIC SILICA POWDER AND GLASS COMPACT USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a crystalline synthetic silica powder low in the concentration of OH group and Cl, which is industrially highly usable and a glass compact obtained by using the same. SOLUTION: The crystalline synthetic silica powder shows diffraction peaks of the cristobalite crystalline phase when it is measured by a powder X-ray diffraction method using CuKαray and contains OH group in a concentration of <=50 ppm and Cl in a concentration of <=50 ppm. The glass compact is obtained by using the silica powder.