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:
Oct. 09, 2012
Filed:
May. 19, 2011
Masato Goto, Nagaokakyo, JP;
Hayato Katsu, Nagaokakyo, JP;
Naoaki Abe, Nagaokakyo, JP;
Atsushi Kishimoto, Nagaokakyo, JP;
Akinori Nakayama, Nagaokakyo, JP;
Masato Goto, Nagaokakyo, JP;
Hayato Katsu, Nagaokakyo, JP;
Naoaki Abe, Nagaokakyo, JP;
Atsushi Kishimoto, Nagaokakyo, JP;
Akinori Nakayama, Nagaokakyo, JP;
Murata Manufacturing Co., Ltd., Nagaokakyo-Shi, Kyoto-fu, JP;
Abstract
A semiconductor ceramic includes a BaTiO-based composition, as a main component, having a perovskite structure represented by general formula ABO. Part of Ba constituting an A site is replaced with at least an alkali metal element, Bi, and a rare-earth element, and the molar ratio m between the A site and a B site is 0.990≦m≦0.999 (preferably 0.990≦m≦0.995). Preferably, part of the Ba is replaced with Ca, and the content of the Ca when the total number of moles of the elements constituting the A site is 1 mole is 0.042 to 0.20 (preferably 0.125 to 0.175) on a molar basis. A PTC thermistor includes a component body formed of the semiconductor ceramic. Accordingly, there are provided satisfactory rise characteristics even if an alkali metal element is present.