The preparation and characteristics of cobalt blue colored mica titania pearlescent pigment by microemulsions

Blue pearlescent pigment was obtained by coating microemulsion-synthesized CoAl2O4 nanoparticles onto mica titania. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed that the spherical CoAl2O4 spinel was around 20 nm and dispersion of the nanoparticles on the coated surface was uniform. EDS revealed that the coating rate and coating efficiency of Co was about 3.12% and 97%, respectively. The study results indicate that the optimum technology parameters were 1:1 CoO:Al2O3 molar ratio, and the coating ratio of CoAl2O4 was 3.7–4.6% by weight.