| abstract |
The present invention provides an additive for lubricating oil comprising a monoester carboxylate (A) represented by formula (1). In formula (1), R 1 represents a single bond in which carbon atoms of a carbonyl group are bonded together, or a divalent hydrocarbon group having 1 to 4 carbon atoms, and R 2 represents a hydrocarbon group having 1 to 22 carbon atoms. AO represents a single oxyalkylene group selected from 2 to 4 oxyalkylene groups or a mixed oxyalkylene group of two or more, and n is the average addition mole number of the oxyalkylene groups represented by AO, It represents 0-5. M represents organic ammonium. |