Surface-treated calcium carbonate and a resin composition obtained by blending it

PROBLEM TO BE SOLVED: To provide a surface treated calcium carbonate for improving low viscosity characteristics, thixotropy or the like of a plastisol or a sealant resin composition. SOLUTION: Calcium carbonate having a BET specific surface area (SW) of 5 to 45 m 2 /g is subjected to surface treatment with a surface treating agent comprising a polymerized fatty acid and another surface treating agent. The treatment amount (As) of the polymerized fatty acid per unit specific surface area ranges from 0.015 to 0.15 [%/(m 2 /g)] and the treatment amount (Ts) of the entire surface treating agents per unit specific surface area ranges from 0.15 to 0.35 [%/(m 2 /g)], wherein As=AG/SW [%/(m 2 /g)] and Ts=TG/SW [%/(m 2 /g)]; AG represents the treatment amount (%) of the polymerized fatty acid on the surface treated calcium carbonate; TG represents the entire surface treatment amount (%) on the surface treated calcium carbonate; and SW represents the BET specific surface area (m 2 /g) measured by a nitrogen adsorption method. COPYRIGHT: (C)2008,JPO&INPIT