| 摘要 |
PROBLEM TO BE SOLVED: To obtain a lubricant which reduces, when used as the lubricant for the back layer of a magnetic recording medium, the coefficient of friction of the surface of the back layer, maintains the coefficient of friction low for a long time, and gives a magnetic recording medium excellent in electromagnetic transduction characteristics, travelling propertis, and durability by using a specific tryptophan ester compd. SOLUTION: This lubricant is a tryptophan ester compd. represented by the formula (R1 and R2 are each a 6C or lower hydrocarbon group; R3 is a long-chain hydrocarbon group; and R4 is H or a hydrocarbon group) having a dialkylamino group. In a magnetic recording medium comprising a nonmagnetic substrate, a magnetic layer formed on one side of the substrate, and a back layer comprising a binder and a nonmagnetic powder dispersed therein and formed on the other side, the back side holds the tryptophan ester compd. |
