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:
Sep. 11, 1990
Filed:
Mar. 14, 1988
Applicant:
Inventors:
Kunihiko Oka, Tsukuba, JP;
Hiromi Unoki, Tsukuba, JP;
Assignee:
Agency of Industrial Science and Technology, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C30B / ;
U.S. Cl.
CPC ...
505-1 ; 505729 ; 1566171 ; 1566181 ; 1566191 ; 156D / ; 423593 ;
Abstract
Lanthanum cuprate, La.sub.2 CuO.sub.4, is a superconductive oxide. In order to prepare a single crystal of lanthanum cuprate, the phase diagram of La.sub.2 O.sub.3 -CuO system is determined utilizing their differential thermal analysis and X-ray diffractometry. Cu oxide and at least one of lanthanum oxide and lanthanum carbonate are mixed in the molar ratio of 71.1-92.9:28.9-7.1. The resulting mixture is heated to be molten. While slowly cooling the melt, nuclei of La.sub.2 CuO.sub.4 precipitate from the melt, growing to single crystals in the melt. As a result, large scale single crystals are prepared.