The Heat of immersion and the Dispersibility of Cadmium Series Pigmentst

Abstract

In order to make clear the influence of the surface structure of cadmium series pigments on their dispersion properties, the heat of immersion of CdS-ZnS. pigments was measured and was compared with their degree of dispersion in plastics. Of all the CdS-ZnS series pigments studied, the heat of immersion of the a-type (hexagonal) samples was 900-960 erg/cm² in water and 220-330 erg/cm² in benzene, and that of the 8-type (cubic) ones was 420-500 erg/cm² in water and 320-440 erg/cm² in benzene. These results indicate that the β -type crystal is more oleophilic than the a-type one and explain the fact that the 8-type crystal is better disperesed in plastics.