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:
Jun. 28, 2016
Filed:
Jan. 19, 2012
Migaku Takahashi, Sendai, JP;
Tomoyuki Ogawa, Sendai, JP;
Yasunobu Ogata, Sendai, JP;
Naoya Kobayashi, Otake, JP;
Chammika Ruwan Polwatta Gallage, Otake, JP;
Kaori Kohara, Otake, JP;
Migaku Takahashi, Sendai, JP;
Tomoyuki Ogawa, Sendai, JP;
Yasunobu Ogata, Sendai, JP;
Naoya Kobayashi, Otake, JP;
Chammika Ruwan Polwatta Gallage, Otake, JP;
Kaori Kohara, Otake, JP;
TODA KOGYO CORPORATION, Hiroshima, JP;
TOHOKU UNIVERSITY, Sendai, JP;
Abstract
Ferromagnetic particles including an FeNcompound phase in an amount of not less than 80% as measured by Mössbauer spectrum and each having an outer shell in which FeO is present in the form of a film having a thickness of not more than 5 nm. Ferromagnetic particles may be made by subjecting iron oxide or iron oxyhydroxide having an average major axis diameter of 40 to 5000 nm and an aspect ratio (major axis diameter/minor axis diameter) of 1 to 200 as a starting material to dispersing treatment to prepare aggregated particles; subjecting the iron compound particles passed through a mesh to hydrogen reducing treatment at a temperature of 160 to 420° C.; and then subjecting the resulting particles to nitridation treatment at a temperature of 130 to 170° C.