| 摘要 |
A lubricating oil additive composition which imparts improved oxidaton properties to crankcase lubricants comprises an antioxidant selected from aromatic or alkyl sulfides and polysulfides, sulfurized olefins, sulfurized carboxylic acid esters and sulfurized ester-olefins, and a primary amine of the formula: <IMAGE> wherein each A is independently hydrogen or alkyl, R is alkyl or alkenyl of at least 6 carbon atoms, R1 is an alkyl group of at least 2 carbon atoms, x is an integer from 2 to 4, y is 1 to 4, and Het forms with the N atom, a 5- or 6-membered heterocyclic ring optionally containing an additional N or O hetero atom. Lubricating oil compositions containing this additive composition are also disclosed. Zn dithiophosphates may, also, be used in the additive composition. |
