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:
Nov. 14, 1978
Filed:
Aug. 02, 1976
Applicant:
Inventors:
Shin-Ichiro Dezawa, Kanagawa, JP;
Koji Sasazawa, Kanagawa, JP;
Tatsuji Kitamoto, Kanagawa, JP;
Nobuo Yamazaki, Kanagawa, JP;
Assignee:
Fuji Photo Film Co., Ltd., Minami Ashigara, JP;
Primary Examiner:
Int. Cl.
CPC ...
C01G / ; C01G / ;
U.S. Cl.
CPC ...
252 6262 ; 252 6256 ; 427127 ;
Abstract
In a process for producing a ferromagnetic powder having a high coercive force which comprises adding an aqueous solution containing Co.sup.+2 ions, or both Co.sup.+2 ions and another cation(s), and an alkali solution to a suspension of a ferromagnetic iron oxide containing the metal(s) given by these ion(s), the improvement wherein said ferromagnetic iron oxide is treated with a reducing agent prior to the preparation of the suspension.