| 摘要 |
A ceramic pigment consists essentially of calcined oxides of zirconium, silicon and iron, the whole or the major portion of which are associated together in the form of an ironcontaining zircon crystal lattice. The admixture of the oxides or oxide producing compounds of Zr, Si and Fe is calcined with compounds giving a source of alkali metal ions, a source of fluoride ions and preferably also a source of halide ions selected from bromide and chloride ions. The percentages by weight of the pigment are ZrO2 35 to 80; SiO2 10 to 55; Fe2O3 0.1 to 10; alkali metal ions (Na and K used) 0.25 to 8.0; fluoride ions 0.25 to 3.0; chloride or bromide ions 0.25 to 8.0. The calcination temperature is 700 DEG C. to 1100 DEG C. |
