| 摘要 |
PURPOSE:To prevent bubble formation in a calcining stage and to obtain high- purity glass at a low temp. by subjecting a mixture of silica sol which is the hydrolyzate of alkyl silicate with fine powder of silicic acid to ultrasonic treatment and calcination. CONSTITUTION:Alkyl silicate represented by a formula Si(OR)4 (where R is 1- 7C alkyl) is dissolved in a solvent, and by adding hydrochloric acid or the like, the alkyl silicate is hydrolyzed to form silica sol. The silica sol is mixed with fine powder of silicic acid, and ultrasonic waves are applied to the liq. mixture to disperse uniformly the powder by further stirring and mixing. The mixture may be filtered. The mixture is then dried by evaporating the solvent, and it is calcined. Thus, bubble formation in the calcining stage is prevented, and high purity glass is obtd. at a low cost. |
