Calcium carbonate pigment for heat-sensitive recording paper, process for preparing same, coating composition for heat-sensitive recording paper and heat-sensitive recording paper

摘要

Disclosed are a calcium carbonate pigment for heat-sensitive recording paper, the pigment having a BET specific surface area of about 17 to about 55 m²/g, an oil absorption of about 90 to about 220 ml/100 g as determined by the Ogura method and a surface acidity of solid substantially represented by the following equation (Z):$\mathop{\mathrm{image}} \[ \text{y=0.13 x + 31} \]$ wherein x is a BET specific surface area (m²/g) and y is a surface acidity of solid (µmol/g); a process for preparing the pigment; coating compositions comprising said pigment each for forming an intermediate layer of heat-sensitive recording layer, and for a heat-sensitive recording layer thereof: and heat-sensitive recording papers obtained by application of the coating compositions.