| 摘要 |
A composition suitable for use as a hydraulic fluid comprises: (a) a lubricating oil preferably in an amount of from 20 to 80% by weight; (b) a minor amount of oil-soluble borate ester; (c) an amine which prevents deposition of oil-insoluble hydrolysis products of the borate ester; and optionally (d) an oil soluble orthoester of the formula: <IMAGE> wherein R7, R8, R9 and R10 are specified groups. |
