US Patent 7407606 Electroconductive powder and method for production thereof

A method for producing a titanium dioxide powder having a well electroconductive layer containing substantially no antimony, which comprises providing a titanium dioxide powder containing specific amounts or less of alkali metals, such as sodium and potassium, alkaline earth metals, such as magnesium and calcium, and metals having a valence of four or less, such as aluminum, zinc and iron, preparing an aqueous suspension of the titanium dioxide powder, adding an acidic aqueous solution containing a tin compound and a phosphorus compound and an alkaline solution to the above aqueous suspension so that the aqueous suspension has a pH in the range of 2 to 6 or 8 to 12, and firing the resulting product at a temperature of 600 to 925° C.