| 摘要 |
PURPOSE: To obtain a lubricating oil which is miscible with a fluoroalkane refrigerant or a chlorofluoroalkane refrigerant over a wide temperature range and excellent in electrical characteristics and does not undergo hydrolysis by using a specified polyoxyalkylene compound as the main constituent. CONSTITUTION: This lubricating oil comprises a mixture of at least one polyoxyalkylene compound represented by formula I [wherein A is a residue obtained by removing the OH groups from a 4-40C compound having an ether linkage and 2 to 20 OH groups in the molecule; R<1> and R<2> are each 2-6C alkylene; R<3> is 1-6C alkyl; R<4> is H or 1-6C alkyl; and a and b are each a positive number, and (l), (m) and (n) are each 0 or a positive number, provided that al+bm=(2 to 100) and l+m+n=(2 to 20)], (particularly having a number- average molecular weight of 300 to 3,000), wherein the mixture has a hydroxyl value of 0-30.0mg KOH/g and the ratio of the butylene groups to all the alkylene groups represented by R<1> and R<2> in formula I satisfies the relation of the formula II (wherein p is the number of butylene groups; and q is the number of 2-6C alkylene groups except butylene groups). |
