Abstract: The present invention provides a grease composition which comprises a base oil and a thickening agent and in which the base oil comprises an ester oil represented by the following general formula (1) and composed of pentaerythritol and a fatty acid, the composition being characterized in that it comprises a pentaerythritol tetra-ester oil in which the fatty acid used for forming the ester, at least, comprises 2-ethyl hexanoic acid in an amount ranging from 51 to 55% by mass and caprylic acid and capric acid in a total amount ranging from 39 to 49% by mass wherein the content of caprylic acid is not less than 30% by mass and that of capric acid ranges from 5 to 10% by mass: C(CH2OCOR1)4, wherein R1 represents a linear and/or branched fatty acid residue having 6 to 12 carbon atoms as well as a bearing comprising the grease composition, filled therein.

Abstract: Disclosed is a grease that provides a prolonged lubricating lifetime to applied portions for use at high temperature, and a grease sealed bearing in which the bearing is sealed with this grease. This grease comprises a base oil, a thickener, and an amide-based wax. The amide-based wax is contained in an amount of 0.5 to 10% by weight based on the total amount of the grease, has a melting point of 80° C. or more, and an antioxidative ability to the base oil. The base oil is at least one base oil selected from the group consisting of an ether-based oil, an ester-based oil and a synthetic hydrocarbon oil, and has kinematic viscosity of 20 to 150 mm2/s at 40° C. The thickener is an urea-based thickener, and is contained in an amount of 5 to 30% by weight based on the total amount of the grease.

Abstract: Disclosed is a grease that provides a prolonged lubricating lifetime to applied portions for use at high temperature, and a grease sealed bearing in which the bearing is sealed with this grease. This grease comprises a base oil, a thickener, and an amide-based wax. The amide-based wax is contained in an amount of 0.5 to 10% by weight based on the total amount of the grease, has a melting point of 80° C. or more, and an antioxidative ability to the base oil. The base oil is at least one base oil selected from the group consisting of an ether-based oil, an ester-based oil and a synthetic hydrocarbon oil, and has kinematic viscosity of 20 to 150 mm2/s at 40° C. The thickener is an urea-based thickener, and is contained in an amount of 5 to 30% by weight based on the total amount of the grease.