MAGNETISCHES AUFZEICHNUNGSMEDIUM, BINDEMITTEL FUER EIN DAFUER VERWENDETES MAGNETISCHES PULVER UND VERFAHREN ZUR HERSTELLUNG EINES BINDEMITTELHARZES FUER DAS MAGNETISCHE PULVER

摘要

The present invention provides a magnetic recording medium comprising a non-magnetic substrate and a magnetic layer formed on a substrate, comprising (a) a binder containing a vinyl chloride resin having sulfoxide groups and (b) a magnetic powder dispersed in the binder (a); and a binder used in said medium for dispersion of magnetic powder, containing a vinyl chloride resin containing sulfoxide groups. The present invention further provides a process for producing said vinyl chloride resin (a binder resin) having sulfoxide groups. The use of the binder resin of the present invention makes it possible to obtain a magnetic coating in which a fine magnetic powder is dispersed stably and which has good coatability. The magnetic recording medium obtained using the magnetic coating has good surface smoothness and good surface durability and is excellent in travelling, magnetic property and electromagnetic conversion property.