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:
Sep. 14, 1993
Filed:
Mar. 09, 1989
Takanobu Takayama, Hachioji, JP;
Kazuetsu Yoshida, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Maxell, Ltd., Osaka, JP;
Abstract
There is disclosed a perpendicular magnetic recording medium having a magnetic layer comprising magnetic metal corpuscles and their oxide formed on a nonmagnetic substrate, and having perpendicular magnetic recording read-write characteristics improved by dispersing the above described magnetic metal corpuscles in the oxide crystal having a NaCl type crystal structure so that the magnetic metal corpuscles may have an isotropic structure instead of a columnar structure. There are also disclosed a method for fabricating such a perpendicular magnetic recording medium and a read-write machine using such a perpendicular magnetic recording medium. Further, there are disclosed a perpendicular magnetic recording medium having perpendicular magnetic recording read-write characteristics improved by applying heat treatment to the magnetic layer in a nonreducing atmosphere, a method for fabricating such a perpendicular magnetic recording medium and a read-write machine using such a perpendicular magnetic recording medium.