| 摘要 |
PURPOSE:To enhance electrical characteristics, durability, and abrasion resistance, by forming a megnetic layer contg. soft and hard type urethane resins both specified in tensile strength, and an epoxy resin or its deriv. CONSTITUTION:The soft type urethane resin has <=200kg/cm<2> tensile strength and >=900% elongation at rupture, and the hard type urethane resin has >=200kg/cm<2> tensile strength and <=900% elongation at rupture. Both said resins used for the magnetic recording medium are polyester polyurthane resin or polyether polyurethane resin or the like synthesized by reacting diisocyanate with polyol synthesized from an org. dibasic acid, such as phthalic acid, glycol, such as ethylene glycol, polyol, such as trimethylolpropane, or a lactone type polyesterpolyol. |
