Yellow ceramic pigment for glaze prodn. - contains oxide(s) of praseodymium, zirconium and silicon

摘要

Compsn. for mfg. yellow ceramic pigments contg. praseodymium, using 1 mole ZrO2, 0.8-1.4 mole SiO2, 0.06-0.4 mole fluoride, 0.1-3.5 mole chloride, 0.1-0.4 mole Pr, and with water equal to 0.5-10 times the moles of chloride employed. The water may be added as such, or be present in the cpds. used in the mixt., which may also contains 0.01-0.1 mole of an alkali nitrate per mole chloride. The mixt. is pref. calcined 0.5-3 hours at 820-980 degrees C. and the resulting prod. employed to mfr. glazes. Prior methods of mfg. a Pr glaze are complicated and expensive. The novel method provides an inexpensive process of making a pigment which is used in glazes to obtain a deep yellow colour.