| 摘要 |
PURPOSE:To improve the wear resistance of a magnetic layer and to obtain the titled magnetic recording medium having excellent durability by using a specified polycyclic ketonic compd. as the lubricant to be incorporated into the magnetic layer. CONSTITUTION:Bicyclic ketonic compds. shown by formulas (1)-(3) are most typically used as the polycyclic ketonic compd. Each carbon ring is preferably composed of 3-8 carbon atoms. Although the carbons are mostly single-bonded, a part of carbons can be double-bonded. Besides, the carbon atoms constituting the carbon ring may have a substituent such as an alkyl, a nitro group, a sulfonic group, a phosphoric group, a halogen, hydroxyl, and carboxyl. Since such a polycyclic ketonic compd. has excellent lubricity and compatibility with the binder resin, excessive oozing out of the compd. onto the surface of the magnetic layer when added into the magnetic layer is controlled in sliding contact with a magnetic head, hence the lubricity can be maintained for a long period, and the wear resistance of the magnetic layer is remarkably improved. |
