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. 25, 1989
Filed:
Dec. 17, 1987
Shinsuke Yano, Nagoyo, JP;
Susumu Nishigaki, Nagoyo, JP;
Hiroshi Kato, Nagoyo, JP;
Toshio Nonomura, Nagoyo, JP;
Narumi China Corporation, Nagoya, JP;
Abstract
A dielectric ceramic composition consisting essentially of a BaO-TiO.sub.2 -WO.sub.3 ternary system wherein molar percentages of BaO, TiO.sub.2 and WO.sub.3 are within the range enclosed by a line joining the points of A(21.5, 78.5, 0), B(40.0, 30.0, 30.0), C(37.0, 30.0, 33.0), D(20.0, 75.0, 5.0), E(21.5, 75.0, 3.5) and A of a composition diagram shown in the attached FIGURE, the range excluding molar percentages of BaO, TiO.sub.2 and WO.sub.3 laying on a line joining said points A, E and D. In the dielectric ceramic composition, up to 10 mole % of TiO.sub.2 may be replaced by tetravalent metal oxide and, further, MnO is contained in amounts of 3 mole % or less with respect to 100 mole % of the sum of BaO, TiO.sub.2 and WO.sub.3. Since the dielectric ceramic composition has a beneficial combination of dielectric properties, particularly a high Q, properly small dielectric constant and sufficiently small temperature coefficient of resonant frequency, .tau..sub.f, and .tau..sub.f, can be adjusted to a desired value in the vicinity of 0 ppm/.degree.C., it is especially greatly useful at the microwave range.