| 摘要 |
PURPOSE:To obtain a magnetic recording medium which has the good surface smoothness of a magnetic layer, and has an excellent electromagnetic conversion characteristic, high modulus of elasticity and excellent mechanical strength by using a copolymerized polyester resin contg. a metallic salt of sulfonic acid and nitrogen element contg. compd. in one molecule and a polyisocyanate compd. in combination as a binder component. CONSTITUTION:A copolymerized polyester resin contg. a metallic salt of sulfonic acid and nitrogen element contg. compd. in one molecule and a polyisocyanate compd. are incorporated as a binder component in a magnetic layer. The copolymerized polyester resin contg. a metallic salt of sulfonic acid and nitrogen element contg. compd. in one molecule has an anionic sulfonic acid metallic chloride and cationic nitrogen element contg. compd. in one molecule and has therefore a good mutual effect with magnetic powder, has excellent dispersibility and packability of the magnetic powder and contributes to an improvement in the surface smoothness of the magnetic layer and an electromagnetic conversion characteristic. The polyisocyanate compd. cross-links and bonds the copolymerized polyester resin by reacting with the hydroxyl group and amino group contained therein and contributes to the improvement in the modulus of a elasticity and mechanical strength of the magnetic layer. |
