Patent ID: 8058216
Filing Date: 2011-11-15
Classification: C10M,C10N,F16C

Abstract:
1. A grease composition for a rolling bearing having heat-resistant properties and performance of preventing an abnormal noise from being generated when it is cold, comprising a base oil, a thickener, and an additive, wherein a worked penetration of said grease composition at 25° C. is 300 or less, and an unworked penetration at −20° C. is 200 or more, wherein said additive comprises poly(metha)acrylate having a weight average molecular weight of 20,000 to 1.5 million, wherein a mixing amount of said poly(metha)acrylate for a total mount of said base oil and said thickener is 3 to 10 wt %, wherein said additive further contains zinc dithiophosphate, wherein said base oil consists of ether oil and poly-α-olefin oil, the ratio of parts by weight of said poly-α-olefin oil to parts by weight of said ether oil for 100 parts by weight of the total amount of said base oil and said thickener is in the range of 50:32 to 64:16, wherein said base oil has a kinematic viscosity of 15 mm wherein said thickener comprises a diurea compound prepared by reacting an amine compound and 4,4′-diphenylmethane diisocyanate, said amine compound being octyl amine and p-toluidine.