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. 13, 1998
Filed:
May. 19, 1995
Applicant:
Inventor:
Masatada Yodogawa, Tokyo, JP;
Assignee:
TDK Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
C04B / ;
U.S. Cl.
CPC ...
264617 ; 264662 ;
Abstract
In preparing a zinc oxide base varistor in the form of a sintered body which itself has a voltage-dependent nonlinear resistance, firing is done in an atmosphere containing at least 60% of oxygen at or above the temperature at which additives form a liquid phase, and thereafter the sintered body is heat treated in an atmosphere containing at least 10% of oxygen at a temperature of 600.degree. to 1,000.degree. C. There is obtained a zinc oxide base varistor having a high energy handling capability, a high nonlinearity index .alpha., and satisfactory load life characteristics such as a humid load life.