| 摘要 |
<p>A refrigerating machine oil composition containing an alicyclic dicarboxylic ester compound which has an alicyclic ring and two ester groups represented by the following general formula (1) -COOR1 (1) (wherein R1 represents a C¿1-30? hydrocarbon group) and in which the two ester groups are bonded respectively to adjacent carbon atoms on the alicyclic ring, the alicyclic dicarboxylic ester compound being a mixture of the cis and trans isomers with respect to the configuration of the two ester groups, the cis/trans isomer ratio being 20/80 to 80/20 by mole. When used in combination with an HFC refrigerant and a natural type refrigerant such as carbon dioxide or a hydrocarbon, the composition is excellent in lubricity, compatibility with the refrigerants, thermal/hydrolytic stability, and electrical insulating properties and enables the refrigerating system to be operated at a higher efficiency.</p> |
