| 摘要 |
PURPOSE: To obtain a lubricating oil which is for use in a refrigerator containing a hydrofluorocarbon as a refrigerant and is excellent in fluorocarbon stability, compatibility, electrical insulating properties, hydrolytic stability, etc., by using a specific ester as a base oil for the lubricating oil. CONSTITUTION: The lubricating oil comprises as a base oil an ester represented by formula I (wherein R1 and R2 each is a 1-9C alkyl; R3 is H or a 1-8C alkyl; the total number of the carbon atoms contained in R1 , R2 , and R3 is 3-12; R4 is a residue of a 2-5C n-hydric alcohol; n is 2-6; and the n groups represented by formula II may be the same or different) (e.g. an ester obtained from trimethylolpropane and 3,3-dimethylpentanoic acid). It preferably further contains an alkylbenzene oil and/or a mineral oil. |
