| 摘要 |
PURPOSE:To obtain a lubricating oil for a refrigerator with excellent miscibility with a hydrofluorocarbon, such as HFC-134a, even at high viscosity by incorporating a specified polyoxyalkylene compd. as an essential ingredient. CONSTITUTION:A lubricating oil for a refrigerator is obtd. by incorporating a polyoxyalkylene compd. of formula [wherein B is a residue of a compd. with 4-8 hydrogen atoms (e.g. polyglycerine or trimethylolalkane); A1 and A2 are each 2-4C alkylene; (a), (b), (l), (m) and (n) are each an integer satisfying a=0-5, b=0-5, l=0-8, m=2-8, n=0-7, (a.l+b.m)=1-20 and (l+m+n)=4-8] as an essential ingredient. HFC-134a which is a hydrofluorocarbon out of regulation among fluorocarbon refrigerants for a refrigerator has been used but the conventional lubricating oil for a refrigerator causes phase separation into two layers at ordinary temp. As the lubricating oil for a refrigerator of the present invention has excellent miscibility with the hydrofluorocarbon such as HFC-134a and retains excellent miscibility even at high viscosity, it is extremely useful. |
