Patent ID: 8044005

Claim:
A lubricant composition for use in a rolling bearing for a motor comprising a base oil and a thickening agent, wherein said base oil is a mixed oil having the following characteristics of (a) to (c): (a) said mixed oil consists essentially of a synthetic hydrocarbon oil and an ester oil; (b) a kinematic viscosity of said mixed oil at 40° C. is 40 to 70 mm 2 /second; (c) a mixing ratio by weight between said ester oil of said mixed oil and said synthetic hydrocarbon oil thereof is 30:70 to 70:30; said ester oil consists of a dipentaerythritol ester oil and has a kinematic viscosity at 40° C. of not less than 30 mm 2 /second; and said thickening agent comprises a diurea compound of formula (1) where R 1 and R 3 are each a n-octyl group or a n-docosyl group and at least one of R 1 and R 3 is a n-docosyl group, and R 2 is an aromatic hydrocarbon group having 6 to 15 carbon atoms, wherein a mixing ratio of said diurea compound to an entirety of said lubricant composition is 5 to 20 wt %.