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:
Mar. 09, 1982
Filed:
Jun. 06, 1980
Applicant:
Inventors:
Assignee:
Toda Kogyo Corp., Hiroshima, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01F / ; H01F / ;
U.S. Cl.
CPC ...
75 / ; 148-635 ; 148105 ; 148 315 ;
Abstract
Fine magnetic particles with high saturation magnetization (over 140 emu/g) as well as high stability against oxidation in air, are produced by a process which comprises the first stage of oxidizing the surfaces of metallic particles consisting mainly of iron in an atmosphere containing both H.sub.2 O and H.sub.2 gases at an oxidizing temperature below 900.degree. C., and the second stage of further oxidizing the surfaces of the particles produced at the first stage in an atmosphere containing O.sub.2 gas.