Abstract: The present invention relates to a lubricating composition, intended for a refrigerant system comprising a gas compression circuit, comprising: at least one first polyalkylene glycol exhibiting a hydroxyl number strictly of greater than 50 mg KOH/g and a kinematic viscosity, measured at 100° C. according to the standard ASTM D445, ranging from 5 to 10 mm2/s, and at least one second polyalkylene glycol with a kinematic viscosity, measured at 100° C., ranging from 100 to 500 mm2/s, said polyalkylene glycols A and B being present in a PAG(s) A/PAG(s) B ratio by weight of between 60/40 and 99/1. It also relates to the employment of such a lubricating composition in a refrigerant system comprising a gas compression circuit, in particular for an automobile air conditioning system, in combination with a coolant based on hydrocarbon compounds, such as R134a and/or HFO-1234yf.

Abstract: The present invention relates to a lubricating composition, intended for a refrigerant system comprising a gas compression circuit, comprising: at least one first polyalkylene glycol exhibiting a hydroxyl number strictly of greater than 50 mg KOH/g and a kinematic viscosity, measured at 100° C. according to the standard ASTM D445, ranging from 5 to 10 mm2/s, and at least one second polyalkylene glycol with a kinematic viscosity, measured at 100° C., ranging from 100 to 500 mm2/s, said polyalkylene glycols A and B being present in a PAG(s) A/PAG(s) B ratio by weight of between 60/40 and 99/1. It also relates to the employment of such a lubricating composition in a refrigerant system comprising a gas compression circuit, in particular for an automobile air conditioning system, in combination with a coolant based on hydrocarbon compounds, such as R134a and/or HFO-1234yf.