| 摘要 |
Metallic dithiophosphates of the formula: <IMAGE> in which R1 is an alkyl, alkenyl, cycloaliphatic, aryl, or heterocyclic radical, R2 and R3 are alkyl radicals, preferably C1-C4 radicals, and m represents the valence of the metal M, M being a metal of Groups IIB, IIIB, IVB, or VIII of the Periodic System of Elements, preferably zinc. They are obtained by the action of P2S5 on a monoester alcohol of the formula: <IMAGE> and then by reaction of a metal oxide, such as zinc oxide, with the dithiophosphoric acid formed. These metallic dithiophosphates are useful as extreme-pressure and anti-wear additives for lubricating oils in amounts of between 0.2 and 10 percent, referred to the weight of lubricating oils. |
