| 摘要 |
PURPOSE:To improve the dispersibility and magnetic characteristic of magnetic powder having small grain sizes and, by using an alkylene diamine deriv. and lecith in in combination as a dispersant. CONSTITUTION:A magnetic recording medium consisting of at least 1 kind of the compds. expressed by the formula I , lecithin and magnetic powder contained in a binder is formed. At least one kind of the compds. expressed by the formula I and lecithin are dissolved in an org. solvent or water, and magnetic powder is dipped at a prescribed ratio in the soln. thereof. The pretreated magnetic powder is thoroughly mixed and dispersed together with a binder and an org. solvent, and if necessary, additives such as a dispersant, lubricant, polishing agent, antistatic agent, etc. are inuorporated therewith. Thereupon, the mixture consisting of such compsn. is coated on a substrate, whereby a magnetic recording layer is formed. Thermoplastic resins, thermosetting resins, reaction type resins, resins curable by electron beam irradiation, and mixture thereof are used as the binder for the magnetic recording medium. |
