| 摘要 |
PROBLEM TO BE SOLVED: To provide a lubricant composition being excellent in fuel consumption-saving property and low temperature viscosity and capable of satisfying both the fuel consumption-saving property and the low temperature viscosity at -35°C or lower while maintaining high temperature high shearing viscosity even if a synthetic oil such as a poly-α-olefin based base oil and an ester based base oil and a low viscosity mineral oil based base oil are not used. SOLUTION: The lubricant composition contains a lubricant base oil having a kinematic viscosity at 100°C of 1-10 mm<SP>2</SP>/s and%C<SB>A</SB>of 5 or lower, and 0.1-50% mass of a viscosity index enhancing agent having a weight average molecular weight of 50,000 or more and a ratio of the weight average molecular weight and PSSI of 0.8×10<SP>4</SP>or higher based on the whole amount of the lubricant composition. The lubricant composition has a kinematic viscosity at 100°C of 3-9.3 mm<SP>2</SP>/s and a ratio of HTHS viscosity at 150°C and HTHS viscosity at 100°C of 0.50 or higher. COPYRIGHT: (C)2009,JPO&INPIT |
