METHOD FOR IMPROVING ANTIWEAR PERFORMANCE AND DEMULSIBILITY PERFORMANCE

摘要

A method for improving antiwear performance and demulsibility performance in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and an antiwear additive as a minor component. The antiwear additive includes a zinc dialkyl dithiophosphate compound represented by the formula;Zn[SP(S)(OR1)(OR2)]2 ;wherein R1 and R2 are independently primary or secondary C1 to C8 alkyl groups. The R1 and R2 primary or secondary alkyl groups of the zinc dialkyl dithiophosphate compound, and the amount of the zinc dialkyl dithiophosphate compound in the lubricating oil, are sufficient for the lubricating oil to exhibit improved antiwear performance and demulsibility performance. The lubricating oils of this disclosure are suitable for use in marine system oils for two-stroke marine diesel engines.

主权项

1. A method for improving antiwear performance and demulsibility performance in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil, said formulated oil having a composition comprising a lubricating oil base stock as a major component; and an antiwear additive as a minor component; wherein the antiwear additive comprises a zinc dialkyl dithiophosphate compound represented by the formula
Zn[SP(S)(OR1)(OR2)]2 wherein R1 and R2 are independently primary or secondary C1 to C8 alkyl groups; andwherein the R1 and R2 primary or secondary alkyl groups of the zinc dialkyl dithiophosphate compound, and the amount of the zinc dialkyl dithiophosphate compound having the R1 and R2 primary or secondary alkyl groups in the lubricating oil, are sufficient for the lubricating oil to exhibit improved antiwear performance and demulsibility performance as compared to antiwear performance and demulsibility performance achieved using a lubricating oil containing a minor component other than the zinc dialkyl dithiophosphate compound having the R1 and R2 primary or secondary alkyl groups, and in an amount other than the amount of the zinc dialkyl dithiophosphate compound having the R1 and R2 primary or secondary alkyl groups in the lubricating oil.