Synthesis of reddish pink pigment by addition of Mg2+ into (Al, Cr)2O3 corundum

Abstract

It is known that the colors of inorganic pigments can be changed by adding of small amount of mineralizers. In this research, the effect of Mg2+ on the coloring of (Al, Cr)2O3-pigment was investigated. The Mg2+-added pigments consisted of (Al, Cr)2O3 corundum and Mg(Al, Cr)2O4 spinel. It was verified that the lattice constants of the corundum phase were not affected by the addition of Mg2+. The valence of Cr in (Al, Cr) 2O3 and in Mg(Al, Cr)2O4 were trivalent as found by X-ray photoelectron spectroscopy. The color changing of the pigments was due to the content of Cr3+ in the Mg(Al, Cr)2O4.