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:
Nov. 08, 2011
Filed:
Feb. 03, 2010
Yuji Umeda, Tokyo, JP;
Fan Zhang, Xiamen, CN;
Yuji Umeda, Tokyo, JP;
Fan Zhang, Xiamen, CN;
TDK Corporation, Tokyo, JP;
Abstract
The dielectric ceramic composition comprising a main component including a compound satisfying a compositional formula of (SrBa)TiO('x' in said compositional formula is 0.159≦'x'≦0.238, and “m” is 0.997≦“m”≦1.011), and a subcomponent comprising 11 to 25 weight % of CaTiO, 0.10 to 0.50 weight % of at least one oxide of element selected from the group consisting of Fe, Co, Ni, Cu, and Zn in terms of FeO, CoO, NiO, CuO, and ZnO, 0.590 to 1.940 mol % of an oxide of element “A” (A is Mn and/or Cr), and an oxide of element “D” where “D” is at least one element selected from a group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, and Y; wherein a ratio (A/D) of the element “A” with respect to element “D” is 2.250 to 7.450. According to the present invention, the dielectric loss (tan δ) at the wide frequency range can be lowered while maintaining a good capacitance temperature characteristic and the specific permittivity, without including Pb and bismuth Bi.