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:
Jun. 02, 1987
Filed:
Jul. 29, 1985
Applicant:
Inventors:
Yasumichi Tokuoka, Saku, JP;
Hitoshi Arai, Saku, JP;
Norio Higuchi, Saku, JP;
Hideki Hotsuki, Saku, JP;
Assignee:
TDK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
428323 ; 428329 ; 428694 ; 428900 ;
Abstract
In a magnetic recording medium comprising a base and a magnetic coating layer formed thereon which consists of ferromagnetic particles dispersed in a binder, the magnetic layer contains from 3 to 15 percent by weight, on the basis of the magnetic powder weight, of abrasive particles having a Mohs hardness of 6 or upward, in such a manner that the average number of the abrasive particles per unit area of the magnetic layer surface is at least 0.25 per square micron. The magnetic powder is a magnetic metal powder based on iron, and the abrasive particles are angular rather than granular in shape.