GREASE TO BE SEALED IN BEARING

摘要

A grease to be sealed in bearings which shows good lubricating properties within a wide temperature range from low to high temperatures, whereby it can prevent bearing noise while it is cold, and maintain its good properties including excellent high-temperature durability for a long period of time. The grease contains a base oil made up of a synthetic hydrocarbon oil and an ester synthetic oil having eight or more ester groups arranged in a comb-like fashion on one side of an oil chain molecule made up of eight of more carbon atoms, as expressed by Formula below, the ratio of contents in weight of the synthetic hydrocarbon oil and the ester synthetic oil being 0.65-0.75 : 0.35-0.25, and 5-20 wt% of a urea thickening agent. The grease may further contain 0.1-10 wt% dithiophosphate as an extreme pressure agent. The grease may be used as grease to be sealed in a ball bearing for supporting a pulley engaging belts for transmitting automotive engine torque to prevent noise immediately after the engine is started. (see fig. I) (where R1-R4 are alkyl groups, and x and y are integers greater than 1).