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:
May. 10, 1977
Filed:
Feb. 17, 1976
Hisayoshi Ueoka, Ichikawa, JA;
Masatada Yodogawa, Tokyo, JA;
TDK Electronics Company, Limited, Tokyo, JA;
Abstract
Semiconducting ceramics are produced by firing a semiconducting composition of the barium titanate type containing vanadium oxide in the amount of 0.001 to 0.5 wt%. A change in the specific resistance over the range of the temperature at which the positive temperature coefficient characteristic of resistivity (PTCR) is exhibited can be increased by as much as 10.sup.5 times and the specific resistance value at room temperature can be controlled at a desired value. By further adding silicon dioxide to the above composition in the amount of 0.05 to 1.5 wt% the above effects can be enhanced, especially the specific resistance at ambient temperature.