| 摘要 |
PURPOSE:To provide the subject working medium containing a fluorinated hydrocarbon and a fluorine-modified polysiloxane in a specified ratio, free from two-phase separation to low temperatures and destruction of the ozone layer, having a minimized moisture absorption and excellent in heat resistance and lubricity. CONSTITUTION:An objective working medium containing (A) 95-40wt.% fluorinated hydrocarbon (e.g. 1,1,1,2-tetrafluoroethane, 1,1,2,2-tetrafluoroethane or hexafluorocyclopropane) prepared by substituting a part or the whole of H of a 2-4C hydrocarbon with F and having >=40 deg.C critical temperature and (B) 5-60wt.% fluorine-modified polysiloxane preferably represented by the formula (m is 0-5; n is value where kinematic viscosity at 25 deg.C is 100-10000cSt). The above-mentioned working medium is effective for improving efficiency of a freezer of air-conditioners, refrigerators, etc., and for improvement of durability thereof. |
