| 摘要 |
PROBLEM TO BE SOLVED: To obtain a lubricant composition capable of manifesting an extremely high oxidation stability by a synergistic effect in both of a lubricant base oil and an antioxidant by using the antioxidant together with the lubricant base oil in a specific composition. SOLUTION: The subject composition is obtained by adding (B) an antioxidant (preferably, at least one kind of antioxidant or the like selected from a hindered phenol-based one, an aromatic amine based one and sulfur-based one) to (A) a mineral oil-based lubricant including >=80 wt.% saturated hydrocarbon component and <=0.79 viscosity-density constant of the saturated hydrocarbon component as the lubricant base oil. For example, the component A is obtained by using a distillate of a paraffin group-based crude oil and/or a mixture group- based crude oil by an atmospheric distillation as a stock oil, refining the stock oil and collecting the lubricant fraction. As a result, the lubricant composition which has an excellent oxidation stability can be provided by specifying the content of the saturated hydrocarbon component in the base oil, and viscosity- density constant of the saturated hydrocarbon component. |
