| 摘要 |
PURPOSE:To provide the magnetic recording medium having a low coefft. of friction and good lubricity and durability by forming a lubricating layer contg. the fluoroalkyl carboxylic acid expressed by prescribed formula or its salt on the magnetic layer of the recording medium. CONSTITUTION:This magnetic recording medium has the magnetic layer on a nonmagnetic base. This recording medium has the lubricating layer contg. the fluoroalkyl carboxylic acid expressed by formula Rf-Y-COOM<1> or formula (Rf-Y-R-COO)KM<2> (OH)2-K or/and the salt of the fluoroalkyl carboxylic acid on the above-mentioned magnetic layer. In the formula, Rf: a fluoroalkyl group, R: a hydrocarbon group contg. at least one of double bonds, Y: an ester bond or ether bond, M<1>: hydrogen, alkaline metal, or primary to quaternary ammonium, m<2> an alkaline earth metal, K: 1 or 2. As a result, the electron- withdrawing property of fluorine is absorbed by the combination group intervening between the fluoroalkyl group and the alkyl group and, therefore, the acidity does not increase unlike the fluoroalkyl carboxylic acid or perfluorocarboxylic acid. The rust preventiveness is good and the coefft. of friction is low. The lubricity and durability are enhanced. |
