Patent ID: 7975508

Claim:
A method for producing high silicate glass, the method comprising: a phase-separating step of subjecting to heat treatment borosilicate glass containing any one element of manganese, cerium, chromium, cobalt, and copper, so as to phase-separate the borosilicate glass; an acid-treatment step of subjecting the phase-separated borosilicate glass to acid treatment so as to elute a metal; and a sintering step of sintering the acid-treated borosilicate glass, wherein the borosilicate glass includes 0.1 wt % to 2.0 wt % of an oxide of the one element of manganese, cerium, chromium, cobalt, and copper, wherein, when the borosilicate glass contains cerium or chromium, the borosilicate glass is subjected repeatedly to another heat treatment and another acid treatment between the acid-treatment step and the sintering step, and wherein a last acid treatment of the another acid treatment performed repeatedly is an acid treatment by using acid containing ethylenediamine tetraacetic acid.