ON FACTORS CONTROLLING THE QUALITY OF ANTIMONY WHITE PIGMENT

Antimony white as a pigment is mainly judged by the degree of whiteness. With a view to improving the quality of the product, tests were carried out to investigate the effect of impurities contamination, the shape and size of the grains, and the crystal structure of antimony oxides. At the same time, methods of producing superfine antimony white on a large scale were also investigated. It was found that amongst the many factors the crystal structure of the grains was most important, thus the greater the amount of cubic antimony trioxide present, the better the quality of antimony white as revealed by its whiteness. Furthermore, long-time tests on a large scale showed that the best quality of antimony white powders could be obtained by suitable control of the primary and secondary oxidizing blast, the forced-air cooling flow, and the reaction chamber temperature.