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. 16, 1992
Filed:
Dec. 26, 1990
Yutaka Shimizu, Saku, JP;
Eizo Tsunoda, Komoro, JP;
TDK Corporation, Tokyo, JP;
Abstract
In a magnetic recording medium comprising a magnetic layer containing a magnetic powder, 5 to 20% by weight based on the weight of the magnetic powder of a non-magnetic abrasive having a Mohs hardness of at least 6, and a binder on a non-magnetic substrate, the magnetic layer becomes more durable while maintaining electromagnetic properties by distributing the abrasive in the magnetic layer such that its concentration is highest in a surface-adjoining portion and continuously decreases therefrom toward the substrate side. The medium is prepared by applying a magnetic coating to a substrate and continuously passing the coated substrate through reversing magnetic fields prior to curing of the coating.