| 摘要 |
PROBLEM TO BE SOLVED: To provide a lubricating oil composition which keeps high abrasion prevention and is excellent in capability to help maintain base number longer and high temperature clearing. SOLUTION: The lubricating oil composition comprises a lubricant base oil which contains at least one compound selected from the group consisting of the metal salt of a thiophosphoric ester or a phosphoric ester represented by formula (1) (wherein X<1> , X<2> , X<3> and X<4> are each oxygen or sulfur, and at least one of them is oxygen, and Y<1> is a bivalent metal atom) and a thiophosphoric ester or a phosphoric ester represented by formula (2) (wherein X<11> and X<12> are each oxygen or sulfur, at least one of them is oxygen, and U is a proton, a univalent metal atom or an ammonium ion), its metal salt or its amine salt. |
