| abstract |
This lubricant contains a protic ionic liquid having a conjugate acid (B + ) and a conjugate base (X = ), and the ionic liquid is represented by general formula (1). Here, in general formula (1), R 1 and R 2 are hydrogen atoms, or R 1 and R 2 form a benzene ring together with the carbon atom to which each is bonded, and R 3 represents a straight-chain hydrocarbon group having at least 10 carbon atoms. |