PURPOSE: To produce a large-sized quartz glass in high yield, by hydrolyzing an alkoxysilane separately with a basic catalyst and an acidic catalyst, mixing the gels obtained by the hydrolysis, and gelatinizing the mixture under a specific pH condition.
CONSTITUTION: An alkoxysilane is hydrolyzed in the presence of a base as a catalyst to obtain a sol dispersed with silica particles having relatively large particle diameter. Separately, the alkoxysilane is hydrolyzed using an acid catalyst to obtain a sol wherein tetrahydroxysilane forms a dimerWtetramer. Both sols are mixed with each other homogeneously, and the mixed gel is adjusted to 3W6pH, gelatinized, dried, and baked. Since the polymerization reaction proceeds uniformly and rapidly, forming a strong network structure, a large-sized quartz glass can be produced in a short time without causing the breakage during the gelatinizing and shrinking stage of the gel and the heating stage of the dried gel.
KANBE SADAO
TOKI MOTOYUKI
TAKEUCHI TETSUHIKO
| JPS56125240A | 1981-10-01 |