Color master bath is mainly made up of pigments, carriers, and additives. Titanium dioxide is one of frequently-used pigment. Using calcined kaolin as extension agent of titanium dioxide has become a frequently-used method for many systems. The major reason for such method is that calcined kaolin is low in cost and excellent in performance (such as easy for color modulation, good dispersibility, good chemical stability, difficult of changing color, and easy for processing). Calcined kaolin produced by our company has become the most ideal extension agent for high whiteness, fine particle, high purity, good dispersibility, and good compatibility with carrier materials).