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.

Date of Patent:
May. 21, 1996

Filed:

Jul. 21, 1994
Applicant:
Inventors:

Chiaki Mizuno, Kanagawa, JP;

Tsutomu Sugisaki, Kanagawa, JP;

Masaya Kojima, Kanagawa, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; B32B / ; B32B / ;
U.S. Cl.
CPC ...
428212 ; 428323 ; 428329 ; 428336 ; 4286 / ; 4286 / ; 4286 / ; 4286 / ; 4286 / ; 428900 ;
Abstract

In a magnetic recording medium comprising a nonmagnetic substrate, a first magnetic layer, and a second magnetic layer mounted in this order, the first magnetic layer has a greater coercive force and a lower residual flux density than the second magnetic layer. When the second magnetic layer is directly mounted on the first magnetic layer, the second magnetic layer has a thickness within the range of 0.05-0.5 .mu.m and a coercive force within the range of 1200-2000 Oe while the first magnetic layer has a coercive force greater than that of the second magnetic layer by 800-2500 Oe and a residual flux density in the range of 30-70% of that of the second magnetic layer. When a nonmagnetic layer is held between the first and second magnetic layers, the first magnetic layer has a coercive force not smaller than 2000 Oe and a residual flux density not greater than 70% of that of the second magnetic layer while the second magnetic layer has a coercive force not smaller than 1200 Oe, a residual flux density not lower than 1600 G, and a thickness not greater than 0.5 .mu.m.


Find Patent Forward Citations

Loading…