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.

Date of Patent:
Nov. 29, 1994

Filed:

Sep. 13, 1991
Applicant:
Inventors:

Akira Ushimaru, Kanagawa, JP;

Hiroshi Hashimoto, Kanagawa, JP;

Kazuko Hanai, Kanagawa, JP;

Keiichi Suzuki, Kanagawa, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
4286 / ; 4286 / ; 428900 ;
Abstract

A magnetic recording medium comprising a subbing layer provided between a nonmagnetic plastic support and at least one of a magnetic layer and a backing layer, the magnetic layer and the backing layer each having a void of 40% by volume or less, and the subbing layer having higher solubility in a 0.5 wt % alkaline aqueous solution at 40.degree. C. than that in water at 40.degree. C. and being soluble in a weak alkaline aqueous solution having an initial pH of less than 13 or a low concentration alkaline aqueous solution having 0.25N or less. The subbing layer comprising a polymer containing acidic polar groups, and the subbing layer being soluble in a weak alkaline aqueous solution having an initial pH of less than 13 or a low concentration alkaline aqueous solution having 0.25N or less. A process for recovery and processing of a magnetic recording medium, the process comprising the steps of: (1) cutting a magnetic recording medium comprising a nonmagnetic plastic support having thereon a magnetic layer and/or a backing layer each having a void of 40% by volume or less; (2) dipping pieces of the magnetic recording medium in a weak alkali having an initial pH of less than 13 or a low concentration alkaline aqueous solution having 0.25N or less with stirring so that a subbing layer in the pieces having higher solubility in an alkaline aqueous solution than that in water is dissolved therein to peel off the magnetic layer and/or the backing layer from the nonmagnetic plastic support, and (3) separating the magnetic layer and/or the backing layer from the nonmagnetic plastic support.


Find Patent Forward Citations

Loading…