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:
Sep. 01, 1992
Filed:
Dec. 05, 1989
Wolfgang Kluge, Baden, CH;
Roger Perkins, Baden, CH;
Marco Rossinelli, Fislisbach, CH;
William J Dawson, Columbus, OH (US);
Asea Brown Boveri Ltd., Baden, CH;
Abstract
A method for manufacturing a precursor powder for use in making a varistor is disclosed. This precursor powder is produced by preparing a homogeneous aqueous dispersion of metal oxides and/or metal hydroxides and heating the dispersion in a closed pressure reactor to a temperature between 200.degree. C. and 350.degree. C. for hydrothermally treating the homogeneous dispersion. The precursor powder produced in the afore-described method is highly homogeneous and of controlled crystal phase and morphology and after mixing with zinc oxide powder can homogeneously be reacted with the zinc oxide in a ceramic process.