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:
Aug. 17, 1999
Filed:
Nov. 06, 1998
Toshihiro Mizui, Ise, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
The present invention provides a microwave dielectric porcelain composition having excellent properties, i.e., practically sufficient relative dielectric constant and unloaded Q value and a very small absolute temperature coefficient of resonant frequency. A novel microwave dielectric porcelain composition is provided, comprising a main component represented by the general formula (Ca.sub.x, Sr.sub.y, Nd.sub.z).sub.1+a TiO.sub.3+b �in which x, y and z each represent a molar ratio, with the proviso that x, y and z satisfy the following relationships: x+y+z=1, 0.780.ltoreq.x .ltoreq.0.900, 0.010.ltoreq.y.ltoreq.0.120, 0.090.ltoreq.z.ltoreq.0.130; a represents a number of from not less than 0.010 to not more than 0.300; and b represents a number of from not less than 0.100 to not more than 1.000!, A1.sub.2 O.sub.3, and at least one of oxides of elements other than Ca, Sr, Nd, Ti and Al, wherein the contents of Al.sub.2 O.sub.3 and said at least one of oxides of elements other than Ca, Sr, Nd, Ti and Al are from 10 to 12% by weight and from 1 to 2%, respectively, based on 100% by weight of the main component. The oxides are preferably Nb.sub.2 O.sub.3 and MnO.sub.2.