| 摘要 |
PURPOSE:To obtain the magnetic recording medium having excellent durable reliability in all practicable environments by incorporating specific aliphat. ester into a magnetic coated film. CONSTITUTION:The aliphat. ester expressed by the formula I is incorporated as a lubricant into the magnetic coated film of the magnetic recording medium. In the formula I, R1, R2 are a satd. alkyl group having 1 to 15C straight chains or branches; the sum of the number of carbon atoms of R1 and R2 is 16 and R3 is a satd. or unsatd. alkyl group having 17C straight chain or branches. Of these groups, the ester in which R1 consists of 7C straight chain or branched alkyl groups and R2 consists of 9C straight chain or branched alkyl group is more particularly preferable. Such ester is exemplified by 2-heptyl undecyl stearate, 2-heptyl undecyl oleate, etc. The durability, coefft. of friction and low starting torque property are greatly improved in this way and the excellent durable reliability even in all practicable environments is obtd. |
