Lubricant composition and bearing

摘要

There are provided a lubricant composition for use in a ball-and-roller bearing with a smaller diameter, and a ball-and-roller bearing with a smaller diameter. The lubricant composition comprises a base oil comprising a non-ester oil containing a synthesized hydrocarbon oil, and a thickener comprising a urea compound; wherein the urea compound is represented by the formula (I): R1-(NHCONH-R2)n (I)where R1 is a group containing an aromatic hydrocarbon, R2 is at least one hydrocarbon group selected from the group consisting of an alicyclic hydrocarbon group having 6 to 12 carbon atoms and an aliphatic hydrocarbon group having 6 to 20 carbon atoms, and n is 2 or 3; wherein the synthesized hydrocarbon oil has kinetic viscosity of 20 mm2/s or more and less than 80 mm2/s at 40° C.; and wherein the base oil comprises 50% by weight or more of the synthesized hydrocarbon oil based on the total weight of the base oil.