Process for preparing silicic acid hydrate

摘要

The present invention provides silicic acid hydrate having a large pore volume and tiny particle diameters, and a process for preparing it. There is disclosed silicic acid hydrate obtained by neutralizing an aqueous solution of sodium silicate with a mineral acid, which has particle properties represented by an oil absorption of 250 to 350 ml/100 g, a total pore volume of 4.0 to 6.0 cc/g, an average pore radius of 200 to 400 ANGSTROM , and an average pore diameter of 3.0 to 15 mu m by the laser method, or 2.0 to 4.0 mu m by the coulter method, or 0.5 to 3.5 mu m by the centrifugal precipitation method.