| 摘要 |
A non-azeoptropic 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 990 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
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