Patent ID: 6649079
Filing Date: 2003-11-18
Classification: C09K

Abstract:
A refrigerant composition for use in low back pressure condition containing a refrigerant and a positive addition of an additive, wherein a) the refrigerant is a mixture of isobutane and 1,1-difluoroethane, the content of the isobutane is in an amount of 25Ëœ35 wt %, the content of the 1,1-difluoroethane is in an amount of 65Ëœ75 wt % and the sum of the isobutane and the 1,1-difluoroethane is 100 wt % based on the total weight of the refrigerant, b) the additive is selected from the group consisting of carbon dioxide (CO2), trifluoromethyl iodide (CF3I) and mixture thereof which prevents flammability of the isobutane, the content of the additive is in an amount of less than 5 wt % based on the refrigerant, and c) the refrigerant composition shows an azeotropic behavior.