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. 30, 1997
Filed:
Sep. 27, 1996
Taro Ohmura, Miyagi, JP;
Sony Corporation, Tokyo, JP;
Abstract
A process for preparing a magnetic recording medium capable of exhibiting excellent magnetostatic properties, electromagnetic conversion properties and travel durability in a high density recording region, is disclosed, which process includes the steps of mixing a magnetic powder having a major axis length of 0.1 .mu.m or less, a first binder composed primarily of a vinyl chloride-based copolymer composed of a sulfonate group and/or a group derived from quaternary ammonium salt, a hydroxyl group and an epoxy group and having an average degree of polymerization of 100 to 200, and a first solvent with each other to form a mixture, and dispersing and diluting the mixture by adding a non-magnetic hard inorganic powder, a second binder and a second solvent to the mixture to prepare a magnetic coating material.