| abstract |
A refrigeration oil composition of the invention comprises (1) a hydrogenated fluoroethane and (2) an ester compound obtainable from: n(2-a) an aliphatic polyhydric alcohol having 1 to 6 primary hydroxyl groups, n(2-b) a saturated aliphatic monohydric straight-chain or branched alcohol having 1 to 10 carbon atoms, and n(2-c) an aliphatic polycarboxylic acid having 2 to 10 carbon atoms or a derivative thereof. n The refrigeration oil composition of the present invention has a sufficient viscosity and a high compatibility with a fluoroethane refrigerant at high and low temperatures and shows a high thermal stability and excellent lubricating properties under the refrigerant atmosphere. |