| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject additive having excellent heat resistance, oxidation stabilization, and cleanability, by forming a perbasic, sulfurinated alkaline earth metal phenate contg. a specified amt. of one or more of compds. selected from plural substd. phenols having different substituents. SOLUTION: This lubricant oil additive comprises a perbasic, sulfurinated alkaline earth metal phenate contg. 0.1-25 mass % of one or more kinds of compds. selected from substd. phenols expressed by the formulae I and II, and it has a base value of 200-450 mgKOH/g. An ultrabasic, sulfurinated alkaline earth metal phenate contg. a sufficient amt. of one or more kinds of substd. phenols, being obtained from source materials of an alkaline earth metal oxide such as calcium oxide or the like, an alkaline earth metal hydroxide such as calcium hydroxide or the like, or the mixture thereof, an alkyl phenol, divalent alcohol such as ethylene glycol or the like, and sulfur, is prepared by a heat reaction and a subsequent carbon dioxide-treatment. In the formulae, R<1> stands for a 9-20C hydrocarbyl group; and R<2> stands for a 14-24C alkyl group. |
