| 摘要 |
<p>A hydraulic fluid of the present invention contains, as a base oil, an ester having two or more ring structures, the two or more ring structures being at least one selected from an aromatic ring and a saturated naphthenic ring. Particularly, the hydraulic fluid contains an ester having two or more aromatic rings as the base oil. The hydraulic fluid has low energy loss due to compression and exhibits excellent responsiveness when being used in a hydraulic circuit. Consequently, the hydraulic fluid realizes energy-saving, high-speed operation and high precision of control in the hydraulic circuit.</p> |
