BINDER FOR MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To provide a binder for a magnetic recording medium ensuring high dispersibility and high strength of a magnetic coating film and also to provide a magnetic recording medium. CONSTITUTION:This binder for a magnetic recording medium contains polyvinyl alkylal resin having polar group-contg. atomic groups introduced by modification with sultones and is used as a binder for a magnetic layer, a nonmagnetic layer, a protective layer and an undercoat layer.