LUBRICANT BASE OIL AND A PROCESS FOR PRODUCING THE SAME, AND LUBRICATING OIL COMPOSITION

摘要

The hydrocarbon-based lubricating base oil of the invention has a urea adduct value of not greater than 4 % by mass, a viscosity index of 100 or greater, and a cycloparaffin content of 30-60 % by mass based on the total amount of the saturated components, as measured by field desorption/ionization mass spectrometry. The hydrocarbon-based lubricating base oil of the invention allows high levels of both viscosity-temperature characteristic and low-temperature viscosity characteristic to be obtained, and exhibits excellence in terms of evaporation property and energy efficiency.