Lubricant compositions

Abstract

Lubricant compositions free of barium salt are described, which comprise A) a lubricant, B) at least one compound of the formula I ##STR1## in which R.sub.1 and R.sub.2, independently of one another are C.sub.1 -C.sub.20 alkyl, C.sub.3 -C.sub.18 alkenyl, phenyl, phenyl substituted by C.sub.1 -C.sub.20 alkyl, phenyl-C.sub.1 -C.sub.4 alkyl, C.sub.2 -C.sub.12 hydroxyalkyl, C.sub.5 -C.sub.12 cycloalkyl, C.sub.5 -C.sub.12 cycloalkyl substituted by C.sub.1 -C.sub.4 alkyl, or naphthyl and Y represents O or S, and C) at least one compound of the formula II, III, or IV ##STR2## in which n is a number from 1 to 4, R.sub.3 is hydrogen, oxyl, hydroxyl, C.sub.1 -C.sub.12 alkyl, C.sub.3 -C.sub.8 alkenyl, C.sub.3 -C.sub.8 alkynyl, phenyl-C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.18 alkoxy, C.sub.5 -C.sub.8 cycloalkoxy, C.sub.7 -C.sub.9 phenylalkoxy, C.sub.2 -C.sub.8 alkanoyl, C.sub.3 -C.sub.5 alkenoyl, C.sub.2 -C.sub.18 alkanoyloxy, benzyloxy, glycidyl or a group --CH.sub.2 CH(OH)--Z in which Z is hydrogen, methyl or phenyl, and, if n is 1 R.sub.4 is hydrogen, C.sub.1 -C.sub.18 alkyl or C.sub.2 -C.sub.18 alkyl which is interrupted by one or more oxygen atoms, C.sub.3 -C.sub.8 alkenyl, cyanoethyl, benzyl, glycidyl, a monovalent radical of an aliphatic or cycloaliphatic, araliphatic or aromatic carboxyylic acid, carbamic acid or phosphorus-containing acid or a monovalent silyl radical, if n is 2 R.sub.4 is C.sub.1 -C.sub.12 alkylene, C.sub.4 -C.sub.12 alkenylene, xylylene, a divalent radical of an aliphatic, cycloaliphatic, araliphatic or aromatic dicarboxylic acid, dicarbamic acid or a phosphorus-containing acid or a divalent silyl radical, if n is 3 R.sub.4 is a trivalent radical of an aliphatic, cycloaliphatic or aromatic tricarboxylic acid, an aromatic tricarbamic acid or a phosphorus-containing acid or a trivalent silyl radical, and, if n is 4, R.sub.4 is a tetravalent radical of an aliphatic, cycloaliphatic or aromatic tetracarboxylic acid, and R.sub.8 is C.sub.1 -C.sub.18 alkyl or a polyisobutylene radical, and R.sub.9 is C.sub.1 -C.sub.8 alkyl. The compositions serve to improve the use properties of the corresponding lubricant and have in particular good resistance to oxidation at high temperatures.

Dependencies are inferred from the claim text.