| abstract |
A lubricating oil composition comprising: a base oil; at least one of acid phosphate represented by the following formulas (1) and (2), wherein the acid phosphate is contained in a range from 0.01% by mass to 3% by mass of a total amount of the composition ; and an antioxidant, where the antioxidant is contained in a range of 0.01% by mass to 10% by mass, based on the total amount of the composition, ** Formula ** where: R1, R2 and R3 are alkyl groups; and at least one of R1 and R2 has 20 to 30 carbon atoms while R3 has 20 to 30 carbon atoms, wherein at least one of R1 and R2 has a side chain, or R3 has a side chain. |