| abstract |
Refrigerator oil composition of the present inventionn n n An alicyclic polyvalent carboxylic acid or derivative thereof (a) having an alicyclic ring and at least two carboxyl groups, wherein at least two of the carboxyl groups are bonded to adjacent carbon atoms on the alicyclic ring,n n n Compounds having two or more hydroxyl groups or derivatives thereof (b) andn n n It contains an alicyclic polyhydric carboxylic acid ester compound obtained using the compound which has one hydroxyl group, or its derivative (c). As a result, when used together with HFC refrigerants and natural refrigerants such as carbon dioxide and hydrocarbons, it becomes possible to balance both lubricity, refrigerant compatibility, thermal and hydrolytic stability, and electrical insulation. |