POROUS QUARTZ GLASS AND METHOD OF PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a porous quartz glass which has high purity and excellent thermal insulation and is also capable of increasing heat resistance. SOLUTION: The porous quartz glass has nitrogen concentration of >=2000 ppm, metal and alkali impurity concentrations of <=0.01 ppm each, only closed pores with a pore diameter of 0.01-10μm and bulk density of 1.5-2.1 g/cm3.