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:
Aug. 06, 1996
Filed:
Dec. 01, 1994
Kouichi Ishiyama, Omiya, JP;
Kazunori Igarashi, Omiya, JP;
Norikazu Komada, Omiya, JP;
Takuo Takeshita, Omiya, JP;
Kiyoyuki Ookubo, Kitamoto, JP;
Mitsubishi Materials Corporation, Tokyo, JP;
Abstract
This invention relates to a magnetic recording powder having a low Curie temperature and a high saturation magnetization (.sigma.s). The magnetic recording powder of this invention is of a composite oxide having a hexagonal ferrite type crystal structure comprises: (a) between 14 and 20 atomic % of at least one of strontium oxide and barium oxide, (b) between 15 and 40 atomic % of chromium oxide, (c) between 2 and 15 atomic % of at least one member of the group consisting of zinc oxide, magnesium oxide and copper oxide, (d) between 2 and 15 atomic % of at least one member of the group consisting of titanium oxide, zirconium oxide and tin oxide, with substantial remainder being iron oxide and unavoidable impurities. Further, the magnetic recording powder of this invention is of a composite oxide having saturation magnetization (.sigma.s) of 15 emu/g or higher, and a Curie temperature (Tc) of 155.degree. C. or lower.