| abstract |
Disclosed is an improved water-based hydraulic fluid composition which comprises an aqueous composition having a viscosity of at least 5 centistokes at 40 DEG C. which contains up to about 95 percent by weight of water, at least 0.1 percent by weight of a carboxylic acid lubricity agent, and an effective amount of an anti-wear additive; wherein the improvement comprises: said anti-wear agent comprising the combination of: (a) mono-, di-, and trihydroxy-substituted aromatic non-carboxylic acid compounds; with (b) substituted aromatic compounds, wherein the substituents comprise mono-, di-, and trinitro groups. |