| 摘要 |
PURPOSE:To give good traveling performance without deteriorating the durability and magnetic characteristics of a magnetic recording medium by incorporating the higher fatty acid ester of diglycerin in said medium. CONSTITUTION:The higher fatty acid ester of diglycerin is obtained by esteri fying a higher fatty acid with diglycerin, and monoester, diester, triester, and tetraester are obtained in accordance with the proportion of said acids to said diglycerin, as shown in reaction equations (1), (2), etc. in which R is a 7-21C hydrocarbon group. As the higher fatty acid ester of diglycerin to be used as a lubricant, any of these esters may be used, but it is especially effective for improving friction coefft., etc., that a part of OH groups of the ester remains in the molecule without being esterified. As the higher fatty acid to be used, 8-22 satd. and unsatd. fatty acids are enumerated, and their hydrocarbon groups may be straight or branched, and preferable examples are linolenic acid, and the like unsatd. acids, etc. |
