Lubricant composition
A lubricant composition applicable to a sliding section or sliding member of an automotive internal combustion engine or power transmission apparatus to significantly lower a friction coefficient. The lubricant composition contains a base oil for a lubricating oil, an oxygen-containing organic compound, a diamond nano-particle and a dispersant for the diamond nano-particle.
1. A lubricant composition for an automotive vehicle, comprising:
a base oil for a lubricating oil, wherein the base oil is suitable for use in an automotive vehicle;
an oxygen-containing organic compound which is constituted of carbon, hydrogen and oxygen and has a hydroxyl group;
a diamond nano-particle; and
a dispersant for the diamond nano-particle, wherein the dispersant is different from the oxygen-containing organic compound, and wherein the dispersant is selected from the group consisting of:
a dispersant containing polyoxyethylene alkyl ether within a range of from 5 to 15 mass % and polyoxyethylene alkyl ether phosphate within a range of from 85 to 95 mass
a dispersant containing polyoxyethylene dialkyl phenyl ether within a range of from 10 to 15 mass % and polyoxyethylene dialkyl phenyl ether phosphate within a range of from 85 to 90 mass %,
a dispersant containing sorbitan monooleate,
a dispersant containing sorbitan dioleate, and
a dispersant containing sorbitan trioleate.
2. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein a content of the diamond nano-particle is within a range of from 0.01 to 3.0 mass %.
3. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the dispersant for the diamond nano-particle is the dispersant containing polyoxyethylene alkyl ether within a range of from 5 to 15 mass % and polyoxyethylene alkyl ether phosphate within a range of from 85 to 95 mass %.
4. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the dispersant for the diamond nano-particle is the dispersant containing polyoxyethylene dialkyl phenyl ether within a range of from 10 to 15 mass % and polyoxyethylene dialkyl phenyl ether phosphate within a range of from 85 to 90 mass %.
5. A lubricant composition as claimed in claim 1 , wherein the dispersant for the diamond nano-particle is the dispersant containing sorbitan trioleate.
6. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a kinematic viscosity of not less than 2 mm 2 /s and not more than 20 mm 2 /s at 100° C.
7. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a kinematic viscosity of not less than 3 mm 2 /s at 100° C.
8. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a kinematic viscosity of not more than 10 mm 2 /s at 100° C.
9. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a kinematic viscosity of not more than 8 mm 2 /s at 100° C.
10. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a viscosity index of not less than 80.
11. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a viscosity index of not less than 100.
12. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the base oil for the lubricating oil has a viscosity index of not less than 120.
13. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the lubricant composition is supplied to a system of lubricant composition-closed type or of lubricant composition-circulated type.
14. A lubricant composition for an automotive vehicle, as claimed in claim 1 , wherein the oxygen-containing organic compound is glycerin monooleate (GMO).
15. A lubricant composition as claimed in claim 1 , wherein the dispersant for the diamond nano-particle is the dispersant containing sorbitan monooleate.
16. A lubricant composition as claimed in claim 1 , wherein the dispersant for the diamond nano-particle is the dispersant containing sorbitan dioleate.