PRECURSOR PARTICLE FOR COMPLEX TITANIUM OXIDE

PROBLEM TO BE SOLVED: To obtain fine PZT (lead zirconate titanate) particles or fine PZT acicular particles hardly causing composition change and capable of being sintered at a low temperature, a PZT thin membrane readily formed on various substrate at the low temperature and having a small surface roughness, and further a precursor particles effective for producing the particles and the membrane. SOLUTION: The objective fine PZT particles capable of being sintered at a low temperature are obtained by carrying out an alkali treatment or a heat treatment of PZT precursor particles obtained by carrying out a reaction of 50-500 mmol/L Pb-containing raw material compound, 0-500 mmol/L Zr- containing raw material compound and 0.002-500 mmol/L Ti containing raw material in an aqueous alkali solution within the temperature range of 0-100 deg.C. The PZT thin membrane good in surface condition is obtained by carrying out a hydrothermal treatment of the PZT precursor particles in the aqueous alkali solution in the presence of a substrate.