| 摘要 |
<p>PURPOSE:To substantially improve the durability of a magnetic layer by incorporating at least one kind of the lubricating agents expressed by the formula Rf-CH2-(R)m-X into a magnetic layer. CONSTITUTION:The lubricating agent expressed by the formula (where, Rf is a fluoropolyoxyalkyl group of 8-152 C, R is an oxyalkylene group of 2-3 C, X is a polar group of any selected from -OH, -OCH2, -COOH, and -OCH2 COOH, m is - 1 integer) is incorporated into the magnetic layer. Since the such agent has the fluoropolyoxyalkyl group contg. carbon atoms at a high ratio and having particularly excellent lubricity, the agent has the excellent lubricating function. The lubricating effect is thus maintained substantially and continuously for a long period of time and the durability of the magnetic layer is substantially improved.</p> |
