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. 17, 2011
Filed:
Jun. 11, 2008
Applicants:
Kazuhiko Itoh, Chuo-ku, JP;
Akira Kakinuma, Chuo-ku, JP;
Atsushi Hitomi, Chuo-ku, JP;
Inventors:
Assignee:
TDK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01C 7/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
A stacked PTC thermistorcomprises a bodyobtained by alternating lamination of a semiconductor ceramic layerand an internal electrode, and a pair of external electrodesprovided at the edge facesof the bodyand electrically connected with the internal electrode. The semiconductor ceramic layeris composed of a porous sintered compact containing crystal grains of a barium titanate-based compound, and an alkali metal element is preferentially distributed in at least one of the grain boundaries and voids of the sintered compact.