摘要 |
The invention concerns refrigerant compositions which comprise a hydrofluorocarbon based refrigerant and, mixed with the refrigerant, a polyol ester based lubricant. According to the invention the polyol ester comprises a diol having a strongly sterically hindered hydrogen attached to the carbon in position 2, said diol being esterified with a mixture of mono- and dibasic carboxylic acids. In particular the diol is 2-ethyl-1,3-hexanediol or 1,4-dimethylol-cyclohexane. The complex esters used in refrigerant mixtures have good lubricant properties and good solubility in HFC compounds. |