| abstract |
Disclosed is a refrigerator oil composition for compressors using hydrofluorocarbons as a refrigerant, comprising (a) a base oil component of a dibasic acid diester and/or a carboxylate of a polyhydric alcohol, and optionally a mineral oil and/or an alkylbenzene, and (b) a phosphate and/or a phosphite, the content of which is from 5.0 to 90.0% by mass of a dibasic acid diester and/or a carboxylate of a polyhydric alcohol in the base oil component. The composition is used as a lubricating oil in refrigerators using, as a refrigerant, hydrofluorocarbons which are substitutes for halogen-containing refrigerants. Using the composition, formation of sludge in high temperature parts may be prevented. The composition is free from wear and has good compatibility with refrigerants, and it is used for a long period of time under high-temperature and high-pressure conditions. |