REFRIGERATOR OIL COMPOSITION, METHOD FOR PRODUCING THE SAME, AND WORKING FLUID COMPOSITION FOR REFRIGERATOR

摘要

PROBLEM TO BE SOLVED: To provide: a refrigerator oil composition for a refrigerant compatible therewith, which has a large effect of abrasion resistance even in severe lubrication conditions such as under the coexistence of a low GWP (global warming potential) refrigerant, and is excellent in long term reliability; a method for producing the refrigerator oil composition; and a working fluid composition for a refrigerator.SOLUTION: This refrigerator oil composition is obtained by blending an ester additive with base oil comprising an ester other than the ester additive, the ester additive being at least one selected from a tetraester comprising pentaerythritol and one selected from 5-18C fatty acids, and a hexaester comprising dipentaerythritol and one selected from 5-18C fatty acids. The blended amount of the ester additive is 2-20 mass% based on the total amount of the refrigerator oil composition, and kinematic viscosity of the refrigerator oil composition at 40°C is 3-500 mm/s.