US 4,282,117 AGranted

Method for producing electrically conductive zinc oxide

AssigneeThe Honjo Chemical Corporation

InventorsMakoto Muramoto, Nobuyuki Ishida, Fujio Matsushita

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Abstract

A method for producing electrically conductive zinc oxide comprising calcining zinc oxide under an ambient atmosphere in a vessel at a temperature from about 800.degree. to about 1100.degree. C. in a mixture thereof with aluminum oxide or a precursor thereof convertible into the oxide under the conditions of treatment in an amount of about 0.05 to about 5 moles based on aluminum atom therein in relation to 100 moles of zinc oxide in the presence of solid carbon. A further improvement in the method comprises mixing zinc oxide with aluminum oxide powder of not more than about 20 millimicrons in average particle size in the dry form to provide a feed mixture, and calcining the mixture, to provide a highly conductive form of zinc oxide.

Claims8

Dependent claims

A method for producing electrically conductive zinc oxide comprising:

calcining zinc oxide under an ambient atmosphere in a vessel at a temperature of about 800.degree. C. to about 1100.degree. C. in a mixture thereof with aluminum oxide or a precursor thereof convertible into the oxide under the conditions of treatment, the precursor being selected from the group consisting of aluminum nitrate, aluminum sulfate, aluminum chloride, aluminum bromide, aluminum hydroxide, aluminum formate and aluminum acetate, in an amount of from 0.5 moles to about 5 moles, based on the aluminum therein, in relation to 100 moles of zinc oxide, in the presence of solid carbon, while allowing the gases generated by the reaction of the solid carbon with the ambient atmosphere to be discharged spontaneously from the vessel as the gases are generated;
and
cooling the thus calcined mixture to a temperature below about 200.degree. C. under a non-oxidizing atmosphere.

Dependencies are inferred from the claim text.