| abstract |
A lubricating oil composition for use in an internal combustion engine having a sliding mechanism comprising a piston ring and a liner, comprising a base oil, (A) poly (meth) acrylate, and (B) an organomolybdenum compound, ) Poly (meth) acrylate is a polymer (A1) containing a repeating unit derived from (meth) acrylate represented by the following formula (1) and having a mass average molecular weight of 1,000 to 500,000. And a lubricating oil composition in which the content of the (B) organomolybdenum compound in the total amount of the composition is 0.01 to 0.2% by mass in terms of molybdenum atoms. (In the formula, R 1 is a hydrogen atom or a methyl group, and X is a hydrogen atom, a hydrocarbon group having 1 to 60 carbon atoms, or a hydrocarbon group having 1 to 60 carbon atoms including a functional group.) |