Grease composition for engine bearing

Abstract

Disclosed is a grease composition for an engine bearing. The grease composition is a hybrid type grease composition which includes: a mixture of an ester-based base oil and a fluorine-based base oil as a base oil; and a mixture of a urea-based thickener and a fluorine-based thickener as a thickener. Accordingly, maximized effects in durability and heat resistance as the grease for an engine bearing may be obtained by optimally blending the base oils, the thickeners and the like.

What is claimed is: 
     
         1 . A grease composition for an engine bearing, comprising:
 an ester-based base oil;   a urea-based thickener; and   an additive,   wherein the grease composition comprises the ester-based base oil in an amount of about 50 to 70 wt %; a fluorine-based base oil in an amount of about 18 to 30 wt %; the urea-based thickener in an amount of about 8 to 15 wt % of; a fluorine-based thickener in an amount of about 1 to 10 wt %; and the additive in an amount of about 1 to 10 wt %, based on the total weight of the grease composition.   
     
     
         2 . The grease composition for an engine bearing of  claim 1 , wherein the additive includes zinc dithiophosphate (ZnDTP) in an amount of about 1 to 2 wt % of, based on the total weight of the grease composition. 
     
     
         3 . The grease composition for an engine bearing of  claim 1 , wherein the base oil composed of the ester-based base oil and the fluorine-based base oil has a kinematic viscosity of in a range from about 90 to about 150 cSt at a temperature of about 40° C. 
     
     
         4 . The grease composition for an engine bearing of  claim 1 , wherein the fluorine-based base oil is a fluorine-based polyether oil. 
     
     
         5 . The grease composition for an engine bearing of  claim 1 , wherein the fluorine-based thickener is polytetrafluoroethylene (PTFE).