| 摘要 |
<p>A non-azeotropic refrigerant composition having a vapour pressure at -20 °C of from 70 to 190 kPa (0.7 to 1.9 bar), at +20 °C of from 510 to 630 kPa (5.1 to 6.3 bar) and at +60 °C of from 1620 to 1740 kPa (16.2 to 17.4 bar), which composition comprises: (a) 1,1,2,2-tetrafluoroethane (R134), 1,1,1,2-tetrafluoroethane (R134a), difluoromethoxytrifluoromethane (E125) or a mixture of two or more thereof, in an amount of from 60 to 99 % by weight, based on the weight of the composition; (b) from 1 to 10 % by weight, based on the weight of the composition, of an unsubstituted hydrocarbon of the formula CnHm in which n is at least 4 and m is at least 2n-2; and, (c) up to 39 % by weight, based on the weight of the composition, of a vapour pressure depressant.</p> |
