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. 24, 1993
Filed:
Jul. 02, 1992
Tokiomi Kato, Nagoya, JP;
Hirofumi Ozeki, Nagoya, JP;
NGK Spark Plug Company, Ltd., Aichi, JP;
Abstract
Disclosed herein is a ceramic composition which gives a microwave dielectric having a permittivity and unloaded Q in a practical range and a small temperature coefficient (.tau.f) in the neighborhood of zero of resonance frequency owing to the controlled amount of ZnO and Ta.sub.2 O.sub.5 added. The .tau.f value may be positive or negative in the neighborhood of zero according to need. The ceramic composition comprises a principal component represented by (BaO-3.7TiO.sub.2).xZnO, where x is in the range of 15.ltoreq.x.ltoreq.17 wt % and a secondary component containing 2-6 wt % Ta.sub.2 O.sub.5 and not more than 1 wt % MnO.sub.2 based on the amount of the principal component. The ceramic composition may also contain BaO-3.8TiO.sub.2, 12-16 wt % ZnO, and 2-6 wt % Ta.sub.2 O.sub.5, or contain BaO-3.6TiO.sub.2, 17-19 wt % ZnO, and 2-6 wt % Ta.sub.2 O.sub.5.