| 摘要 |
PURPOSE:To obtain a refrigerator oil excellent in stability against oxidation and heat by adding a specified amount of a specified polymer as a viscosity index improver to a naphthenic mineral oil, a paraffinic mineral oil, an alkylbenzene synthetic oil or the like. CONSTITUTION:The title oil is prepared by adding 3-12wt.%, based on the base oil, ethylene/alpha-olefin copolymer of an average molecular weight of 2600-3400, represented by the formula (wherein x=a+b; R is alkyl; and a and b are integers), as a viscosity index improver to a naphthenic mineral oil, a paraffinic mineral oil, an alkylbenzene synthetic oil or the like. |
