-watermisciblemetalworkingfluids(syntheticandemulsifiableMWF)AdditinRC5250inwater-basedsystemsdisplaysmultifunctionalproperties:EP-performance,lubricity,corrosioninhibitionandco-emulsification.TypicaltreatmentlevelsinMWFconcentratesare2to10%.AdditinRC5250isemulsifiableinwaterbyneutralizationwithinorganicalkalizingagentsoralkanolamines.Usingtapwaterwithhighhardness,awell-balancedcombinationwithCalciumdispersantsisnecessary.AdditinRC5250increasestheEP-performanceandlubricityduringthemachiningofsteelandlightmetals.AsynergisticEP-performancecanbeachievedinemulsifiableorsemisyntheticMWFincombinationwithAdditinRC2526orAdditinRC2540.FurthermoreAdditinRC5250isanalternativetotalloilfattyacids.