abstract |
A lubricant, which includes an ionic liquid including a conjugate base and a conjugate acid including 2 or more cations in a molecule of the conjugate acid, wherein the conjugate acid includes a monovalent group including a straight-chain hydrocarbon group having 6 or more carbon atoms, and an acid that is a source of the conjugate base has a pKa in acetonitrile of 10 or less. |