Mg^<2+>添加によるクロムアルミナ赤色顔料の合成

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 Mg^<2+> on the coloring of(Al, Cr)_2O_3-pigment was investigated. The Mg^<2+>-added pigments consisted of(Al, Cr)_2O_3 corundum and Mg(Al, Cr)_2O_4 spinel. It was verified that the lattice constants of the corundum phase were not affected by the addition of Mg^<2+>. The valence of Cr in(Al, Cr)_2O_3 and in Mg(Al, Cr)_2O_4 were trivalent as found by X-ray photoelectron spectroscopy. The color changing of the pigments was due to the content of Cr^<3+> in the Mg(Al, Cr)_2O_4