| 摘要 |
PURPOSE:To impart good libricity to the above-mentioned medium and to greatly improve its durability by using an ester compd. having a specific structure as a lubricant. CONSTITUTION:The ester compd. expressed by formula I is incorporated into the magnetic layer of a nonmagnetic base. The ester compd. can be synthesized by dehydration esterification reaction from branched stearic acid and various kinds of 10 to 22C alcohols, such as n-decanol, n-hexadecanol and n-octadecanol. The ester compd. is used at 1 to 15 pts. wt., more preferably 3 to 10 pts. wt. in total per 100 pts. wt. magnetic powder. The ester compd. is previously incorporated into a magnetic coating material or a sol. of a general-purpose solvent, such as isopropaneol or hexane, is applied on a magnetic coated film after the formation of this film and is dried to impregnate the ester compd. into the film. The application of the ester compd. is allowed by the similar method even on the medium formed with the magnetic layer on the nonmagnetic base by a sputtering or vapor deposition method. |
