Abstract
Three phenomena were investigated: (1) Tensile strength of polyurethane-phenoxy resin-polyisocyanate binder system, (2) adhesion for the base material of Ba-ferrite particles and the binder system, and (3) durability of the perpendicular flexible mgnetic disc. the following results were obtained. Tensile strength and adhesion for polyethylene telephthalate, that is the base material, increase with the increase of phenoxy resin and polyisocyanate content ratio. And durability of the magnetic disc improves with the increase of phenoxy resin and polyisocyanate content ratio. Durability of flexible magnetic disc is influenced remark ably by the tensile strength of binder and adhesion for polyethylene telephthalate. A magnetic disc having a tensile strength above 200 kg/cm2 and adhesion above 3.5kg/cm2 can maintain durability for more than 5 million passes.
