| 摘要 |
PROBLEM TO BE SOLVED: To provide an antioxidant which shows a higher antioxidant activity compared to that of conventional antioxidants such as ZDTP and MoDTC and is capable of imparting a higher level of long-drain property to a lubricant, and a lubricant composition using the antioxidant. SOLUTION: The antioxidant represented by the formula (wherein A is an aromatic ring; X is a sulfur atom, an oxygen atom or a nitrogen atom; R is an organic group; a is an integer of 0-1; and b is an integer of 1-3 or 0-3) is a reaction product of a transition metal compound and an aromatic compound and has a structure wherein a transition metal atom and an aromatic ring are bound to each other via a sulfur atom, an oxygen atom or a nitrogen atom that composes the aromatic ring and/or its substituent. The antioxidant is excellent in antioxidant activity, NOx resistance and high-temperature detergency. COPYRIGHT: (C)2006,JPO&NCIPI |
