SYNTHETIC AMORPHOUS SILICATE BONDED WITH ZIRCONIUM AND ITS PRODUCTION

摘要

PURPOSE:To produce the titled silicate having low liquid absorption and suitable as a dentifrice base, by forming procipitated fine silicate powder in the presence of a water-soluble inorganic zirconyl salt. CONSTITUTION:An aqueous solution of a mineral acid (e.g. sulfuric acid) (acid concentration ; about 5-15wt%) containing a specific amount of a water-soluble inorganic zirconyl salt (e.g. zirconyl sulfate) is added dropwise to an aqueous solution of a water-soluble alkali metal silicate (e.g. sodium silicate) (SiO2 concentration; about 5-15wt%), and is made to react at about 50-100 deg.C (the pH at the end of the reaction is made to about 2-8) to obtain a synthetic amorphous silicate bonded with zirconium [the ratio of zirconium (in terms of ZrO2) to SiO2; 0.1-10wt%].