| abstract |
An additive for lubricant or fuel, comprising at least one member selected from substituted hydroxy aromatic ester derivatives represented by general formulae (I) and (II), (wherein R1 through R5 represent each an organic group having six or more carbon atoms; a, b, d, e, k and m represent each 1 to 3; c, f, g, i and j represent each 0 to 3; h represents 0 to 4, provided f+g=1 to 3 and h+i=1 to 6); a lubricant or fuel additive composition containing the same; and a lubricant or fuel composition containing the same. The additive is suitable as an ashless cleaning agent that is excellent in high-temperature stability and can substitute for metallic cleaning agents. The lubricant or fuel composition containing the same is suitable as an internal-combustion engine lubricant or fuel capable of coping with future severe exhaust gas regulation. |