Patent ID: 7820723

Claim:
A method for preparation of a sol of lead zircon titanate, termed PZT, of formula PbZr x Ti (1−x) O 3 with 0.45≦x≦0.7, comprising the steps in sequence of: (a) preparing a concentrated sol by mixing in a diol a titanium-based precursor, a zirconium-based precursor, and a lead-based precursor; (b) holding said concentrated sol at ambient temperature, without agitation , and measuring the viscosity of the sol as a function of time; and (c) once the viscosity of said sol attains a constant viscosity as a function of time. diluting the sol obtained in step (b) with a solvent compatible with the diol used in step (a): and wherein the concentrated sol of step (a) has a concentration of from about 20 to about 40% PZT equivalent per unit mass.