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. 19, 2000
Filed:
Jul. 09, 1998
Yoshiharu Toshima, Yamaguchi, JP;
Takayuki Araki, Yamaguchi, JP;
Takao Hayashi, Yamaguchi, JP;
Hiroyuki Shimamura, Tokyo, JP;
Mitsui Mining and Smelting Co., Ltd., Tokyo, JP;
Abstract
A method for preparing nickel fine powder is herein disclosed, which comprises the steps of mixing an aqueous sodium hydroxide solution comprising, on the basis of the total weight of the sodium hydroxide present in the aqueous solution, 75 to 85% by weight of liquid caustic soda as specified in JIS K 1203 and 25 to 15% by weight, in total, of at least one of sodium hydroxide as specified in JIS K 8576 and solid caustic soda as specified in JIS K 1202, with an aqueous solution of nickel sulfate to form nickel hydroxide, then reducing the resulting nickel hydroxide with hydrazine and recovering nickel fine powder produced. The nickel fine powder prepared by the method has an average particle size of the primary particles ranging from 0.1 to 0.9 .mu.m, a D.sub.90 value of not more than 2.1 .mu.m and a tap density of not less than 3.5 g/cc. The nickel fine powder has a low degree of aggregation, a narrow particle size distribution and a high tap density and therefore, the powder is quite suitably used as a material for producing an internal electrode for a laminated ceramic condenser.