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. 27, 1991
Filed:
Jul. 18, 1990
Yoshisuke Yamakawa, Niiza, JP;
Yoshihiro Honjo, Saku, JP;
Hiroshi Kawahara, Saku, JP;
Masashi Hayama, Saku, JP;
TDK Corporation, Tokyo, JP;
Abstract
A magnetic recording medium is used with a magnetic recording system in which a baseband recording signal is recorded on a magnetic recording medium and a surface-band recording signal with the effective recording depth being smaller than that of the baseband recording signal is then recorded thereon in superimposed relation. The non-magnetic substrate includes thereon a first magnetic layer and a second magnetic layer on that order, said second magnetic layer having a thickness substantially equal to the effective recording depth of said surface-band recording signal and a coercivity higher than that of said first magnetic layer.