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. 10, 2012
Filed:
Dec. 11, 2009
Hayato Katsu, Juelich, DE;
Hayato Katsu, Juelich, DE;
Murata Manufacturing Co., Ltd., Nagokakyo-Shi, Kyoto-fu, JP;
Abstract
A semiconductor ceramic material which contains no Pb and has a high Curie point, low resistivity, and PTC characteristics is represented by the formula ABOwherein A includes Ba, Ca, an alkali metal element, Bi, and a rare-earth element, and B includes Ti. The semiconductor ceramic material contains 5 to 20 molar parts and preferably 12.5 to 17.5 molar parts of Ca per 100 molar parts of Ti. The ratio of the content of the alkali metal element to the sum of the content of the bismuth plus the content of the rare earth element, is preferably from 1.00 to 1.06. The semiconductor ceramic material preferably further contains 0.01 to 0.2 molar parts of Mn per 100 molar parts of Ti.