| abstract |
A refrigerating machine oil composition for carbon dioxide refrigerants which consists mainly of a mixture of (A) 40 to 99.1 wt.%, excluding 40 wt.%, polyvinyl ether having a dynamic viscosity at 100°C of 3 to 50 mm2/s and (B) 0.1 to 40 wt.%, excluding 40 wt.%, polyoxyalkylene glycol having a dynamic viscosity at 100°C of 3 to 50 mm2/s. It has satisfactory lubricating properties and a high viscosity index even in the presence of a refrigerant consisting mainly of carbon dioxide. The composition can be excellent in stability and lubricating properties and used over long even in an atmosphere of supercritical carbon dioxide, while retaining those features. |