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

Abstract Blue pearlescent pigment was obtained by coating microemulsion-synthesized CoAl 2 O 4 nanoparticles onto mica titania. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed that the spherical CoAl 2 O 4 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:Al 2 O 3 molar ratio, and the coating ratio of CoAl 2 O 4 was 3.7–4.6% by weight.