Patent ID: 7846884

Claim:
A lubricating oil composition comprising (a) at least one oil of lubricating viscosity and (b) an effective amount of at least one thio-functionalized phenylenediamine compound of the general formula: wherein R 1 is a straight or branched, substituted or unsubstituted, C 1 -C 30 alkyl, a substituted or unsubstituted C 3 -C 30 cycloalkyl, a substituted or unsubstituted C 3 -C 30 cycloalkenyl, a substituted or unsubstituted C 5 -C 30 aryl, a substituted or unsubstituted C 5 -C 30 arylalkyl, a substituted or unsubstituted C 5 -C 30 heteroaryl, a substituted or unsubstituted C 3 -C 30 heterocyclic ring or a C 1 -C 20 ester; R 2 and R 3 together with the nitrogen atom to which they are bonded are joined together to form a heterocyclic group optionally containing one or more additional heterocyclic atoms; R 4 is independently a straight or branched, substituted or unsubstituted, C 1 -C 30 alkyl, a substituted or unsubstituted C 3 -C 30 cycloalkyl, a substituted or unsubstituted C 3 -C 30 cycloalkenyl, a substituted or unsubstituted C 5 -C 30 aryl, a substituted or unsubstituted C 5 -C 30 arylalkyl, a substituted or unsubstituted C 5 -C 30 heteroaryl, a substituted or unsubstituted C 3 -C 30 heterocyclic ring or a C 1 -C 20 ester, and n is 1.