PURPOSE: To efficiently produce CaCO3 spherical powder with a low kinematic friction coefficient and high fluidity by reacting an aq. soln. of a water sol. Ca salt of a specified concn. and an aq. soln. of a water sol. carbonate at a specified temp. or below.

CONSTITUTION: A 10-2W3mols/l aq. soln. of a water sol. Ca salt such as CaCl2 and a 10-2W3mols/l aq. soln. of a water sol. carbonate such as Na2CO3 are reacted at 70°C or below to produce spherical CaCO3. This CaCO3 is filtered, dried, and treated with a higher fatty acid, whereby it is stabilized to prevent the particle form from changing even in hot water.