LUBRICATING OIL COMPOSITION FOR REFRIGERATORS AND METHOD FOR LUBRICATION WITH THE COMPOSITION

摘要

A lubricating oil composition which comprises (A) a refrigerant comprising a hydrocarbon having 1 to 8 carbon atoms as the main component and (B) a base oil comprising a hydrocarbon exhibiting a degree of non-aromatic unsaturation of 10 % or below and a kinematic viscosity of 5 mm<2>/s or above at 100 DEG C or a polyalkylene glycol derivative represented by general formula (I): R<1>O-(PO)a-(EO)b-R<2> (wherein R<1> and R<2> are each independently hydrogen, C1-C10 alkyl or C2-C10 acyl; PO is oxypropylene; EO is oxyethylene; and a and b are positive numbers including 0 and satisfying the relationship: 2 /s at 100 DEG C. This composition can attain effective lubrication in compression refrigeration cycles wherein refrigerants comprising hydrocarbons as the main component are used, thus improving the wear resistance, stability, lubrication performance and sealing properties and refrigeration efficiency.