| 摘要 |
PURPOSE:To obtain the magnetic recording medium having excellent durability by incorporating at least one kind selected from the phosphate or phosphite expressed by specific formula into a magnetic layer. CONSTITUTION:In the formula, x denotes 1 to 3 integer; R is 7 to 29C a satd. or unsatd. alkyl group having a straight chain or branch. The phosphate expressed by formula I or the phosphite expressed by formula II or formula III is synthesized by the reaction of phosphorus oxytrichloride and alcohol or the reaction, etc., of phosphorus trichloride and alcohol. Such phosphate and phosphite have the slightly poor compatibility with a binder and more particularly a polyurethane resin and are eventually liable to bleed out on the surface of the magnetic layer, thereby exhibiting an excellent lubricating effect on the surface of the magnetic layer. The good temp. cycle durability and high-temp. durability are obtd. and the traveling durability is additionally improved. |
