| 摘要 |
PROBLEM TO BE SOLVED: To provide a working medium for a heat cycle, which working medium has a small global warming potential (GWP) and furthermore can be substituted for HFC-134a and has small composition change and excellent cycle performance (capacity), and to provided a composition for a heat cycle system and a heat cycle system using the composition.SOLUTION: The working medium for a heat cycle is provided which contains an azeotrope-like composition composed of 1 to 99 mass% of (Z)-1,2-difluoroethylene (HFO-1132(Z)) and 99 to 1 mass% of 1,1,1,2-tetrafluoroethane (HFC-134a) and/or 2,3,3,3-tetrafluoropropene (HFO-1234yf). |
