SPHERICAL CALCITE-TYPE CALCIUM CARBONATE, ITS PREPARATION, AND ABRASIVE FOR TOOTHPASTE

摘要

PURPOSE:To prepare the titled calcium carbonate having mild abrasive action to the tooth, capable of improving the gloss of the tooth, and giving an abrasive for tooth paste having stable quality for a long period, by the heat-treatment of spherical vaterite-type calcium carbonate. CONSTITUTION:Spherical vaterite-type calcium carbonate is converted to spherical calcite-type calcium carbonate at a conversion of almost 100%, by the heat treatment at 400-800 deg.C for 0.5-24hr under 1-10 atm. in air or in an inert gas atmosphere. The spherical calcite-type calcium carbonate keeps its psherical shape stably for a long period even in the presence of water. When it is used as an abrasive for toothpaste, it exhibits mild abrasive action to the tooth, polishes the surface of the tooth excellently to improve the gloss of the tooth, improves the dispersibility of the toothpaste in the mouth, and gives improved feeling to the mouth.