| 摘要 |
<p>Lubricating oil compositions of internal combustion engines are described which comprise (A) a major amount of oil of lubricating viscosity, and minor amounts of (B) at least one carboxylic derivative composition produced by reacting (B-1) at least one substituted succinic acylating agent with (B-2) at least one amine compound characterized by the presence within its structure of at least one HN < group, said acylation agents being characterized by the presence within their structure of an average of at least 1.3 succinic groups, and (C) at least one metal salt of a dihydrocarbyl dithiophosphoric acid wherein (C-1) the dithiophosphoric acid is prepared by reacting phosphorus pentasulfide with an alcohol mixture comprising at least 10 mole percent of isopropyl alcohol and at least one primary aliphatic alcohol containing from about 3 to about 13 carbon atoms, and (C-2) the metal is a Group II metal, aluminum, tin, iron, cobalt, lead, molybdenum, manganese, nickel or copper. The oil compositions of the invention also may contain (D) at least one carboxylic ester derivative composition, and/or (E) at least one neutral or basic alkaline earth metal salt of at least one acidic organic compound, and/or (F) at least one partial fatty acid ester of a polyhydric alcohol.</p> |
