| 摘要 |
PURPOSE:To improve the yield of dry gel bodies by making the particle size of fine silica gel particles in a sol for a clad different from the particle size of fine silica gel particles in a sol for a core in a sol-gel process using sols each contg. an alkyl silicate and fine silica gel particles. CONSTITUTION:An alkyl silicate is hydrolyzed in the presence of a basic catalyst to obtain fine silica particles having an arbitrary particle size. When fine silica particles having the same particle size are used, the clad and core of a dry gel body have different bulk densities. The bulk density of a dry gel body is lowered in accordance with an increase in the particle size. When the particle size of fine silica particles in a sol for a clad is made different from the particle size of fine silica particles in a sol for a core, the clad and core of a dry gel body have the same bulk density. Thus, the yield of dry gel bodies is improved. |
