| abstract |
Provided are a surface-treated calcium carbonate filler useful in a curable resin, for imparting performance having excellent heat resistance, color fastness, strength and elongation, and a curable resin containing the filler. n A surface-treated calcium carbonate filler for a curable resin composition, in which calcium carbonate synthesized using compact limestone is treated by a surface treatment agent, the surface-treated calcium carbonate filler satisfying the following formulae (1) to (4):n n0≤Mg≤2000, (1)n n0≤Fe≤200, (2)n n70≤SFa≤100, and (3)n n0≤Ufa≤30, (4)n nMg: a proportion [ppm] of magnesium contained in surface-treated calcium carbonate, Fe: a proportion [ppm] of iron contained in surface-treated calcium carbonate, SFa: a proportion [wt %] of saturated fatty acid in the surface treatment agent comprising a water-soluble monovalent salt of a fatty acid, and UFa: a proportion [wt %] of unsaturated fatty acid in the surface treatment agent comprising a water-soluble monovalent salt of a fatty acid. |