| 摘要 |
PURPOSE:To obtain preservable stability excellent even under severe conditions, such as high temp. and high humidity or low temp. and low humidity, and always stable traveling durability by incorporating specific tertiary branched fatty acid ester into a magnetic magnetic particle layer. CONSTITUTION:The tertiary branched fatty acid ester expressed by formula I is incorporated into the magnetic layer or is made to exist on the surface of the magnetic layer. In the formula I, R<1>, R<2>, R<3> respectively independently denote 1 to 18C hydrocarbon group; R<4> denotes 1 to 24C hydrocarbon group; the total number of carbon atoms of this ester is 12 to 40. The tertiary branched fatty acid produced by a Koch method from olefins is usable as the tertiary branched fatty acid used for synthesizing the tertiary branched fatty acid ester expressed by the formula I. The high preservable stability of the lubricant itself is obtd. under the severe conditions of the high temp. and high humidity or low temp. and low humidity. In addition, the excellent effect of lowering the coefft. of friction is obtd. and the always stable and excellent traveling durability is obtd. |
