MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To improve the durability and surface characteristic of a magnetic recording medium and to extremely improve the electromagnetic conversion characteristic thereof by using a thermoplastic polyurethane/urea resin having electron ray sensitive double bonds and siloxane bond in the molecule as a bonder for a magnetic layer. CONSTITUTION:The magnetic layer contains the thermoplastic polyurethane/urea resin having the electron ray sensitive double bonds in the molecule and the siloxane bond in the molecular chain as the binder. The totaled concn. of the urethane group and urea group of the thermoplastic polyurethane/urea resin is preferably 1.8-3.0mmol/g. The electron ray sensitive double bonds to be introduced to the thermoplastic polyurethane/urea resin are exemplified by the double bonds of acryl and methacryl and these double bonds can easily cleave to form the crosslinked constitution when irradiated with electron rays. The siloxane group concn. of the thermoplastic polyurethane/urea resin is preferably 0.03-3mmol/g.