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. 05, 1981
Filed:
Oct. 29, 1979
Shinobu Fujiwara, Nikahomachi, JP;
Kiyoshi Furukawa, Akita, JP;
Nobuaki Kikuchi, Akita, JP;
Osamu Iizawa, Honjo, JP;
Hitoshi Tanaka, Nikahomachi, JP;
TDK Electronics Co., Ltd., Tokyo, JP;
Abstract
A basic ceramic composition of high dielectric constant type ceramic composition comprises from 68.67 to 69.19% of PbO, from 3.67 to 4.09% of MgO, from 24.17 to 26.99% of Nb.sub.2 O.sub.5 and from 0.25 to 2.97% of TiO.sub.2, all percentages being by weight. Modified composition may comprise additive of Pb(Mn.sub.2/3 W.sub.1/3)O.sub.3, Pb(Mn.sub.1/3 Nb.sub.2/3)O.sub.3, Pb(Mn.sub.1/3 Ta.sub.2/3)O.sub.3, Pb(Mn.sub.1/2 W.sub.1/2)O.sub.3, MnO, and MgO. Modified composition may comprise Ba, Sr and Ca, which replace Pb of the basic ceramic composition. In a modified composition, the content of B site elements may be larger than that of A site element of an ABO.sub.3 crystal of the high dielectric constant type ceramic composition. A high dielectric constant, low dielectric loss, low temperature dependence of capacitance, high insulation resistance and a low sintering temperature are provided by the ceramic compositions of the present invention.