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:
Jun. 02, 1998
Filed:
Mar. 14, 1996
Hidetoshi Mizutani, Aichi, JP;
Masahiko Okuyama, Aichi, JP;
Noritaka Yoshida, Aichi, JP;
Hirofumi Ozeki, Aichi, JP;
Hiroshi Katagiri, Aichi, JP;
NGK Spark Co., Ltd., Nagoya, JP;
Abstract
Powders of BaCO.sub.3, TiO.sub.2, ZnO, etc. are mixed to each other at a predetermined ratio of quantity, calcined in an atmospheric air at 90.degree.-120.degree. C., and pulverized to obtain a calcined powder having an average grain size from 1 to 3 .mu. m. 0.1 to 20 parts-by weight of a powder having an average grain size from 0.1 to 1.5 .mu.m comprising a glass having a transition point of not higher than 450.degree. C. obtained by mixing powders of Pb.sub.3 O.sub.4, SiO.sub.2, Na.sub.2 O, etc. to each other, melting and then pouring into water and pulverizing the thus obtained glass is admixed to the calcined powder. The mixture is dried, pelleted by adding a resin and the pellet powder is molded into a cylindrical shape, applied with CIP (Cold isotactic press), and the molding product after the treatment is sintered in an atmospheric air at 850.degree. to 1000.degree. C. to obtain a dielectric ceramic sintered at low temperature. The resultant dielectric ceramic has high denseness and high unloaded Q value while maintaining .tau.f within a practical range.