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:
Feb. 11, 1986
Filed:
Sep. 08, 1982
Applicant:
Inventors:
Osamu Kubo, Yokohama, JP;
Tadashi Ido, Ebina, JP;
Tutomu Nomura, Yokohama, JP;
Koichiro Inomata, Yokohama, JP;
Assignee:
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Primary Examiner:
Int. Cl.
CPC ...
C04B / ;
U.S. Cl.
CPC ...
252 6259 ; 252 6258 ; 252 6263 ;
Abstract
A method for preparing a magnetic powder for high density magnetic recording includes melting a mixture containing the fundamental component of a hexagonal ferrite, a substituting component for reducing the coercive force, and boron trioxide as a glass forming substance in predetermined amounts. The resultant molten material is rapidly cooled to obtain an amorphous body which is then heat-treated to produce desired substituted type hexagonal ferrite particles in the glass matrix.