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:
Dec. 13, 1983
Filed:
Nov. 25, 1980
Applicant:
Inventors:
Assignee:
TDK Electronics Co. Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; B32B / ;
U.S. Cl.
CPC ...
428403 ; 252 6254 ; 252 6256 ; 360134 ; 360135 ; 360136 ; 427128 ; 428692 ; 428694 ; 428900 ;
Abstract
A magnetic recording medium comprises a substrate coated with a magnetic composition comprising a cobalt adsorbed iron oxide powder with a phosphoric ester type anionic surfactant at a ratio of 2 wt. % or more and a binder at a ratio of said iron oxide powder to said binder of 4 or more. A magnetic recording medium has a coercive force Hc of 950 to 1200 Oe and a residual magnetic flux .phi..sub.r of 0.35 to 0.6 maxwell.