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:
Oct. 12, 1993
Filed:
Jun. 24, 1992
Narito Goto, Hino, JP;
Nobuyuki Sekiguchi, Hino, JP;
Konica Corporation, Tokyo, JP;
Abstract
A magnetic recording medium is disclosed. The medium comprises a support and provided thereon, a plurality of magnetic layers containing a magnetic powder and a binder, wherein an outermost magnetic layer of said magnetic layers comprises a ferromagnetic metal powder having an average major axis length of not more than 0.25 .mu.m and a crystallite size of not more than 200 .ANG. and carbon black having an average particle diameter of not less than 30 m.mu. in an amount of not more than 1% by weight, said outermost magnetic layer having a thickness of not more than 1 m.mu. and a surface roughness R.sub.10z of not more than 50 nm, and at least one magnetic layer other than said outermost layer comprises a cobalt-containing magnetic iron oxide powder having an average major axis length of not less than 0.25 .mu.m and a crystallite size of not less than 250 .ANG., said magnetic layer having a coercive force of from 500 to 1200 Oe.