Grease composition for constant velocity joint and constant velocity joint containing the composition sealed therein

摘要

The present invention provides a grease composition for use in constant velocity joints, which comprises the following components (a) to (g) and a constant velocity joint comprising the grease composition sealed or encapsulated therein: (a) a base oil; (b) a diurea thickener represented by the following general formula: R1NH—CO—NH—C6H4-p-CH2—C6H4-p-NH—CO—NHR2 wherein R1 and R2 each independently represents an alkyl group having 8 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms or a cycloalkyl group having 6 to 12 carbon atoms; (c) a molybdenum dialkyl dithiocarbamate insoluble in the base oil; (d) a molybdenum dialkyl dithiocarbamate soluble in the base oil; (e) molybdenum disulfide; (f) at least one member selected from the group consisting of calcium phenate and calcium sulfonate; and (g) a sulfur-containing extreme-pressure agent free of phosphorus. The grease composition can efficiently prevent a temperature rise of a constant velocity joint and can impart excellent durability to the joint.