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:
Apr. 24, 2001
Filed:
Sep. 15, 1999
Applicant:
Inventors:
Assignee:
NGK Spark Plug Co., Ltd., Aichi, JP;
Primary Examiner:
Int. Cl.
CPC ...
C04B 3/5465 ;
U.S. Cl.
CPC ...
C04B 3/5465 ;
Abstract
Disclosed is a dielectric ceramic material represented by composition formula: (uLi,O—vNa,O)—wSm,O,—xCaO—yTiO,, having a solid solution structure made up of perovskite crystals represented by Ca,Sm,TiO,, perovskite crystals represented by Li,Sm,TiO,, and perovskite crystals represented by Na,Sm,TiO,. Substitution of part of Ti in the composition with at least one of Ga and Al provides a dielectric ceramic material with a particularly increased value of unloaded quality coefficient. The absolute value of the temperature coefficient of resonance frequency is controlled to a small value by adjusting the proportions of Li and Na.