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. 16, 1996
Filed:
Jun. 23, 1994
Teruo Kumagai, Ibaraki, JP;
Tsuneyuki Kanai, Hitachi, JP;
Atsuko Soeta, Mito, JP;
Takaaki Suzuki, Katsuta, JP;
Kazutoshi Higashiyama, Katsuta, JP;
Tomoichi Kamo, Ibaraki, JP;
Shinpei Matsuda, Ibaraki, JP;
Kunihiro Maeda, Hitachi, JP;
Akira Okayama, Hitachi, JP;
Hideyo Kodama, Katsuta, JP;
Akira Yoshinari, Katsuta, JP;
Yoshimi Yanai, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method of producing a high-temperature oxide superconducting material, which comprises the steps of (a) preparing a material corresponding to an oxide superconductor of the perovskite type structure consisting essentially of a first member selected from the group consisting yttrium, lanthanoids, thallium and bismuth; at least one alkaline earth metal; copper; and oxygen and (b) heating the material in the presence of an alkali metal selected from the group consisting of potassium, sodium, rubidium and cesium to a temperature around the melting point of the alkali metal or to a higher temperature for a time sufficient to effect grain growth in the superconductor material, thereby to produce the superconductor containing the alkali metal in an amount not larger than 4 mole % based on the first member.