| 摘要 |
PURPOSE:To prevent the deterioration due to oxidation, by forming a surface treating film made of a specified dicarboxylic acid having an alkyl group or the acid anhydride thereof on a magnetic metallic film such as a vapor-deposited metallic film. CONSTITUTION:A dicarboxylic acid prepared by substituting an alkyl group for hydrogen in at least one inner methylene group of malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid or azelaic acid and represented by the general formula (where n is an integer of 1-7, at least one of n- pieces of R is an alkyl group, and the other is H) is stuck to the surface of a magnetic metallic film such as a vapor-deposited metallic film on a substrate by about 1-500mg/m<2>. The anhydride of said dicarboxylic acid may be used in place of the dicarboxylic acid. |
