| abstract |
Lubricating oil comprising an ester base stock prepared from an aliphatic mono or polyhydric C5-C15 alcohol having no beta-hydrogens to the -OH group, and an aliphatic mono or polycarboxylic C2-C14 acid and contg. (a) 0.5-5% wt. of an alkylated diphenylamine antioxidant, (b) 0.5 to 4.5% wt. of an alkylated phenyl naphthylamine antioxidant, (c) 0.005 to 1.5% wt. copper passivator, (d) 0.5 to 5% wt. (RO)3PO where R = tolyl, phenyl, xylyl, C1-C10 alkyl or cycloalkyl and (e) 0.01 to 5% wt. dispersant polymer. This lubricant has outstanding oxidation stability, corrosion resistance, load-carrying ability and low temp. fluidity and is suitable for use in modern aero gas turbine engines. It is also clean in use. |