PRODUCTION OF CRYSTALLINE TITANIC ACID BASED PEROVSKITE-TYPE FINE PARTICLE

摘要

PURPOSE: To obtain the subject fine particles by mixing a Ba compound or an Sr compound in a solution state with a Ti compound in a solution state or a slurry state at a temperature higher than starting temperature of the reaction. ;CONSTITUTION: As raw material compounds, hydroxides, oxides, salts, alkoxides of Ti and Ba or Sr, preferably hydroxides thereof are used. The Ba compound and the Sr compound may be used ringly or jointly. The atom ratio of Ba or Sr to Ti in mixing is 1.0-50 and the initial concentration of the reaction of Ba or Sr is 0.3-3.5mol/kg water. The mixing temperature is 60-120°C and as the mixing means, an inline mixer is preferably used. The reaction time is preferably normally about 30min to 5hr, though the reaction time is not especially limited. By this reaction, the object fine particles having ≤0.05μm average particle diameter and narrow particle size distribution is obtained. Furthermore, a coprecipitate obtained by dissolving a salt of rare-earth element (e.g. Y or La) in an aqueous solution of titanium salt and hydrolyzing them may be added to the reactional system.;COPYRIGHT: (C)1994,JPO&Japio