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. 09, 1988
Filed:
Sep. 04, 1987
Hiroshi Endo, Yokohama, JP;
Shigeo Iiri, Yokohama, JP;
Masaru Hayashi, Yokohama, JP;
Tsutomu Yamashita, Yokohama, JP;
Satoshi Yamaguchi, Tokyo, JP;
Motoo Seimiya, Yokosuka, JP;
Kabushiki Kaisha Toshiba, , JP;
Abstract
High-purity molybdenum or tungsten powder can be produced by a process comprising (a) decomposing a powder or an oxide powder of molybdenum or tungsten with hydrogen peroxide water; (b) bringing the resulting aqueous solution of molybdenum or tungsten into contact with a cation exchange resin; (c) concentrating the aqueous solution; and (d) reducing a concentrated solid material. By omitting reducing step (d), one can obtain high-purity molybdenum or tungsten oxide powders. Because the Mo and W powders and MoO.sub.3 and WO.sub.3 powders prepared by this invention are of an extremely high purity, they are useful as materials for targets of VLSI elements.