Research on the low-temperature synthesis of cobalt aluminum spinel type blue pigments

Abstract In this paper, CuxCo1−xAl2O4 (x = 0.1–0.5) blue pigments have been successfully synthesized by combustion method at a low temperature (700 °C). Replacing Cu2+ for Co2+ in CoAl2O4 pigment enhanced the violence of the combustion reaction and the spinel-type precursor can be directly obtained. Therefore, it is conducive to synthesis of CoAl2O4 pigment at a low temperature. The intensity of blue hue of CuxCo1−xAl2O4 (x = 0.1–0.5) pigments decreases with increase of the Cu/Co ratio, and it increases with increase of the calcination temperature. When the “x” is the optimal value of 0.1, the CuxCo1−xAl2O4 pigment prepared at 700 °C exhibited excellent color performance similar to the previously reported CoAl2O4 pigment, which the chromatic value is L* = 39.51, a* = −16.67, b* = −21.58, C* = 27.27. After applying the pigments in transparent glaze and ceramic ink, the pigments exhibit high tinting strength and stability, indicating its potential application in ceramic decoration and ceramic ink-jet printing technology. This work provides a facile strategy of synthesis spinel-type powder at a low temperature.