Grease composition for use in constant velocity joints

Abstract

A grease composition which has a good compatibility with boots made of rubber or thermoplastic elastomer, and which also gives enhanced endurance, low wear and low friction in use in constant velocity joints is disclosed. A grease composition is suggested comprising a) at least one base oil; b) 5% by weight to 40% by weight of at least one calcium sulphonate soap and/or calcium sulphonate complex soap as a thickener; and c) at least one molybdenum containing additive.

1 . A grease composition for use in constant velocity joints comprising:
 a) at least one base oil;   b) 5% by weight to 40% by weight of at least one calcium sulphonate soap and calcium sulphonate complex soap as a thickener; and   c) at least one molybdenum containing additive.   
     
     
         2 . A grease composition according to  claim 1 , wherein the composition comprises 12% by weight to 20% by weight of at least one calcium sulphonate soap and calcium sulphonate complex soap. 
     
     
         3 . A grease composition according to  claim 1  wherein the at least one molybdenum containing additive is selected from a group comprising at least one molybdenum dithiocarbamate, at least one molybdenum dithiophosphate, MoS 2 , at least one S-free and P-free organic molybdenum compound, and at least one trinuclear molybdenum compound. 
     
     
         4 . A grease composition according to  claim 1 , wherein the molybdenum containing additive is selected from a group comprising at least one molybdenum dithiocarbamate and at least one trinuclear molybdenum compound. 
     
     
         5 . A grease composition according to  claim 3 , wherein the molybdenum containing additive comprises 0.2 wt.-% to 5 wt.-% of at least one trinuclear molybdenum compound. 
     
     
         6 . A grease composition according to  claim 3 , wherein the molybdenum containing additive comprises 0.25 wt.-% to 5 wt.-% of at least one molybdenum dithiocarbamate. 
     
     
         7 . A grease composition according to  claim 3  wherein the molybdenum dithiocarbamate is selected from a group comprising at least one solid molybdenum dithiocarbamate. 
     
     
         8 . A grease composition according to  claim 3 , wherein the molybdenum containing additive comprises 0.3 wt.-% to 2.0 wt.-% of at least one trinuclear molybdenum compound and 0.5 wt.-% to 3 wt.-% of at least one molybdenum dithiocarbamate. 
     
     
         9 . A grease composition according to  claim 4 , wherein the molybdenum containing additive further comprises at least one molybdenum dithiophosphate. 
     
     
         10 . A grease composition according to  claim 1 , wherein the base oil composition comprises at least one of poly-α-olefins, naphthenic oils, paraffinic oils, and synthetic organic esters. 
     
     
         11 . A grease composition according to  claim 1 , further comprising at least one anti-oxidation agent, at least one corrosion inhibitor, at least one anti-wear-agent, at least one wax, at least one friction modifier and/or at least one extreme pressure agent. 
     
     
         12 . A grease composition according to  claim 1 , wherein the composition comprises 65 wt.-% to 86.9 wt.-% of a base oil composition, 16 wt.-% to 20 wt.-% of at least one calcium sulphonate soap and/or calcium sulphonate complex soap, 0.3 wt.-% to 2.0 wt.-% of at least one trinuclear molybdenum compound and 0.5 wt.-% to 3 wt.-% of at least one molybdenum dithiocarbamate. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled)