| 摘要 |
<p>A lubricating oil composition that is free of organic friction modifiers, comprising (A) an oil of lubricating viscosity in a major proportion; (B) as an additive component in a minor proportion, a separately-prepared oil-soluble zinc salt of a dithiophosphoric acid, the dithiophosphoric acid being the reaction product of phosphorus pentasulphide with one or more alcohols, at least 50 mole % of the alcohol(s) having formula ROH where R is linear C18 to C26 saturated or double-bond unsaturated hydrocarbyl group; and (C) as an additive component in a minor proportion, a separately-prepared oil-soluble zinc salt of a dithiophosphoric acid, the dithiophosphoric acid being the reaction product of a phosphorus pentasulphide with one or more aliphatic alcohols consisting of an alcohol or alcohols each having from three to eight carbon atoms.</p> |
