Refrigerator oil composition, and method of using the composition for lubrication

摘要

Provided is a refrigerator oil composition comprising a refrigerant that comprises carbon dioxide (CO2) as the essential component, and an ester-based lubricating oil composition; wherein the ratio of refrigerant/lubricating oil composition falls between 99/1 and 10/90 by weight. The refrigerator oil composition has good lubricity and sealability and can be stably used for a long period of time in a compression refrigeration cycle in which is used a refrigerant comprising CO2 as the essential component. Also provided is a method of using the composition for lubricating a compression refrigeration cycle equipped with an oil separator and/or a hot gas line.