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:
Jul. 15, 2003
Filed:
Jul. 18, 2001
Hideto Mizutani, Osaka, JP;
Minoru Yoneda, Osaka, JP;
Toshihiro Sugaya, Osaka, JP;
Hiroyoshi Urasumi, Osaka, JP;
Chiyo Honda, Osaka, JP;
Hiroshi Nakao, Osaka, JP;
Tsutomu Hatanaka, Osaka, JP;
Shinji Ohgama, Osaka, JP;
Kiyoshi Fukai, Osaka, JP;
Kazuhiko Nagano, Osaka, JP;
Shigefumi Kamisaka, Osaka, JP;
Kazunobu Abe, Osaka, JP;
Sakai Chemical Industry Co., Ltd., Osaka, JP;
Abstract
A process for the production of fine powder of metallic nickel which comprises a first step of dissolving nickel carbonate and/or nickel hydroxide in aqueous ammonia or in an aqueous solution of ammonia and at least one selected from the group consisting of ammonium carbonate, ammonium hydrogencarbonate, a carbonate of an alkali metal and a hydrogencarbonate of an alkali metal to prepare an aqueous solution of a nickel salt; converting the aqueous solution of a nickel salt to a W/O emulsion, and then removing volatile components including ammonia from the droplets to form precipitates of nickel carbonate in the droplets, thereby providing fine spherical particles of nickel carbonate; and a second step of heating the particles of nickel carbonate in the presence of a fusion preventive agent that is a compound of at least one element selected from the group consisting of alkaline earth elements, aluminum, silicon and rare earth elements in an atmosphere of hydrogen, thereby reducing the nickel carbonate to metallic nickel.