| 摘要 |
PURPOSE:To provide a lubricating oil excellent in lubricity, low in hygroscopicity, good in cleanness, suitable as an oil for refrigerating machine by using, as cooling medium, an ozone layer-nondepleting CFC like R-134a, containing each specific two kinds of polycarbonates. CONSTITUTION:The objective lubricating oil is suitable for car coolers or electric refrigerators and as an industrial gear oil or automotive engine oil, containing (A) a polycarbonate derived from an adduct such as a propylene oxide adduct or ethylene oxide adduct of a pentaerythritol derivative of formula I [R1 is formula II (R2 is <=30C hydrocarbon group or 2-30C hydrocarbon group bearing ether linkage; R0 is ethylene group or propylene group; (n) is 1-24)] and (B) another kind of polycarbonate of formula III (R3 is 1-6C hydrocarbon group or glycol ether group; R4 is ethylene group or propylene group; X is 1-60; (n) is 0. 5-10 on average). |
