MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To increase the packing density of magnetic powder and to improve a magnetic characteristic by constituting a primer coating layer of a nonmagnetic substrate of a thermosetting polyurethane resin. CONSTITUTION:A polyurethane resin of a thermosetting type is coated on a nonmagnetic substrate and is thermoset. The polyurethane resin of a thermosetting type is hardly soluble in an ordinary solvent used for a magnetic paint and has high adhesion to a nonmagnetic substrate such as a polyester film or the like. Therefore if such polyurethane resin is thermoset, the adhesion of the magnetic layer is improved even if the primer coating layer is extremely thin. The packing density of magnetic powder is increased as well.