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. 09, 1993
Filed:
May. 16, 1991
Applicant:
Inventors:
Tetuya Nakazumi, Osaka, JP;
Mikio Kishimoto, Osaka, JP;
Toshinobu Sueyoshi, Kyoto, JP;
Seigi Kawarai, Hyogo, JP;
Assignee:
Hitachi Maxell, Ltd., Ibaraki, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; G11B / ;
U.S. Cl.
CPC ...
428403 ; 252 6255 ; 4286 / ; 428900 ; 148105 ; 148306 ; 148307 ; 148310 ; 148311 ; 75348 ; 75369 ; 106403 ;
Abstract
An acicular alloy base magnetic powder comprising iron and cobalt, which has an average particle long axis size of not larger than 0.25 .mu.m, an axial ratio of from 4 to 8, a cobalt content of from 8 to 50% by weight based on the weight of iron and saturation magnetization of at least 120 emu/g after being kept standing at the temperature of 60.degree. C. and relative humidity of 90% for a week, which has improved corrosion resistance and can provide a magnetic recording medium suitable for recording in the short wavelength range.