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. 15, 1978
Filed:
May. 21, 1975
Applicant:
Inventors:
Assignee:
Sony Corporation, Tokyo, JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H01F / ;
U.S. Cl.
CPC ...
428412 ; 428413 ; 428425 ; 428539 ; 428900 ;
Abstract
A magnetic recording medium comprising a base, for example, of a non-magnetic plastic resin, and a magnetic layer coated on the base and composed of a binder with a magnetic powder dispersed therein, is provided with a friction-reducing additive in the magnetic layer constituted by a boron compound obtained by the esterification of boric acid with a polyhydric alcohol having vicinal hydroxyl groups, such as, glycerin. The amount of such boron compound is from 1 to 15, and preferably, from 4 to 10 parts by weight for each 100 parts by weight of the binder. The preferred boron compounds are those including mono- or di-esters of a fatty acid with or without ethylene oxide.