LUBRICATING OIL FOR COMPRESSOR FOR FLUOROHYDROCARBON REFRIGERANT, METHOD OF USING THE OIL FOR LUBRICATING COMPRESSOR FOR FLUOROHYDROCARBON REFRIGERANT, AND HYDRAULIC FLUID COMPOSITION FOR COMPRESSOR FOR FLUOROHYDROCARBON REFRIGERANT

摘要

PURPOSE:To provide a lubricating oil which has a low pour point even when having a high viscosity, does not cause clouding, and has excellent solubility in the fluorohydrocarbon refrigerant at low and high temps. and an excellent lubricating effect on not only iron but aluminum materials. CONSTITUTION:This oil comprises as the base oil at least one polyoxyalkylene glycol derivative represented by the formula R1-O-[(OP)p(EO1)q]-(EO2)r-R2, and has a kinematic viscosity at 100 deg.C of 7-30cSt. In the formula, R1 is methyl or ethyl; R2 is hydrogen, methyl, or ethyl; PO is oxypropylene; EO1 and EO2 each is oxyethylene; p, q, and r are the average degrees of polymerization of PO, EO1, and EO2, respectively; [(PO)p(EO1)q] is a random copolymer segment made up of PO and EO1; (EO2)r is a polymer block of EO2; 0.70=p/(p+q)=0.95; and 0.03=r/(p+q+r)=0.30.