| 摘要 |
PROBLEM TO BE SOLVED: To obtain a lubricating oil compsn. which has excellent lubricity, heat stability, and oxidation resistance, forms no carboxylic acid and can reduce hygroscopicity by incorporating at least one member selected from among an alkylbenzene, a mineral oil, and a poly-αolefin and a particular cyclic ketal. SOLUTION: This lubricating oil compsn. comprises (a) at least one member selected from the group consisting of an alkylbenzene, a mineral oil, and a POLY-αolefin; and (b) a cyclic ketal or a cyclic acetal prepd. from at least one polyhydric (valency: an even number of 4 to 10) alcohol and a carbonyl compd. represented by the formula (wherein R<1> and R<2> represent H or a 1-18C straight-chain, branched or cyclic alkyl or combine with each other to form a 2-36C alkylene) or its reactive deriv., i.e., a ketal or an acetal, the component (a) to the component (b) wt. ratio being (0.1:99.9) to (99.0:1.0). |
