Patent ID: 8722597

Claim:
A lubricating oil composition for an internal combustion engine, comprising as essential components the following component (A), component (B), and component (C), wherein a phosphorus content of the composition is 50 ppm by mass to 1,000 ppm by mass and a molybdenum content of the composition is less than 1,000 ppm by mass: Component (A): at least one mineral oil; Component (B): at least one compound represented by the following formula (1), wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, Z represents a hydrocarbon group represented by formula (6), formula (7), or formula (8) and n represents a number from 1 to 10, wherein an average of n is 1.06 to 1.4; and Component (C): at least one metal-containing antioxidant selected from the group consisting of (i) a molybdenum dithiocarbamate compound represented by the following formula (3), (ii) a molybdenum dithiophosphate compound represented by the following formula (4), (iii) a molybdenum amine obtained by reacting a hexavalent molybdenum compound with a primary or secondary amine represented by the following formula (5), and (iv) a mixture of a zinc dithiophosphate compound represented by the following formula (2) and the molybdenum dithiocarbamate compound represented by the formula (3), the molybdenum dithiophosphate compound represented by the formula (4) and/or the molybdenum amine obtained by reacting the hexavalent molybdenum compound with the primary or secondary amine represented by the formula (5), wherein R 9 and R 10 each independently represent a hydrocarbon group having 1 to 20 carbon atoms, and a represents a number of 0 to 1/3; wherein R 11 , R 12 , R 13 and R 14 each independently represent a hydrocarbon group having 1 to 20 carbon atoms, and X 1 , X 2 , X 3 and X 4 each independently represent a sulfur atom or an oxygen atom; wherein R 15 , R 16 , R 17 and R 18 each represent a hydrocarbon group having 1 to 20 carbon atoms, and X 5 , X 6 , X 7 and X 8 each independently represent a sulfur atom or an oxygen atom; R 19 —NH—R 20 (5) wherein R 19 and R 20 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 40 carbon atoms, provided that R 19 and R 20 do not both represent hydrogen atoms.