Patent ID: 7137278
Filing Date: 2006-11-21
Classification: C03C

Abstract:
1. A process of producing aluminosilicate glass containing more than 13.5% by weight, based on oxide content, of aluminum oxide and free of alkali metals, apart from inevitable impurities, said process comprising the steps of: a) formulating a batch of raw materials; b) adding at least one fining agent to said batch; c) melting the batch to form molten glass, said melting including fining and homogenizing; and d) after the melting, hot-forming the molten glass formed from the batch; wherein the batch contains from 0.005% by weight to 0.6% by weight of at least one sulfate, based on SO whereby said aluminosilicate glass is formed containing more than 13.5% by weight, based on oxide content, of said aluminum oxide and free of said alkali metals, apart from said inevitable impurities.