The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 14, 1992
Filed:
May. 23, 1990
Kevin A Fothergill, Darlington, GB;
Tioxide Group PLC, London, GB;
Abstract
A composition suitable for use in the manufacture of a ceramic material comprises free-flowing substantially non-aggregated particulate zirconia. A substantial proportion of the zirconia is present in the tetragonal crystalline form and the particles of zirconia contain alumina in an amount of from 1 to 10% by weight expressed as Al on ZrO.sub.2. The particles are substantially free of silica. The particles of zirconia can be coated with an oxide or hydrous oxide of a stabilizing agent for zirconia such as an oxide or hydrous oxide of yttrium, calcium, magnesium, barium, strontium or cerium. An oxidation process is described for the manufacture of the tetragonal crystalline zirconia by the oxidation of zirconium halide in the presence of aluminium halide at high temperature in the vapor phase.