| 摘要 |
PURPOSE:To improve durability and traveling property by making combination use of specific unsatd. aliphat. fluoro group-contg. alkyl ester carboxylate and an antioxidant. CONSTITUTION:The unsatd. aliphat. fluoro group-contg. alkyl ester carboxylate expressed by formula I and the antioxidant are held in the magnetic layer on a nonmagnetic base. In the formula, R denotes an unsatd. aliphat. hydrocarbon group; (m) denotes integer >=4; (n) denotes integer >=1 and <=2m+1. While the unsatd. fluoroester carboxylate has an excellent lubricating effect, this fluoroester alone generates deterioration by oxidation with lapse of time and gradually decreases the lubricating effect. The deterioration of the ester by the oxidation is, however, prevented if the unsatd. fluoroester carboxylate and the antioxidant are used in combination and, therefore, the excellent lubricating effect is exhibited continuously over a long period of time. |
