Glycerol-containing functional fluid

Abstract

A functional fluid comprising a major amount of an oil of lubricating viscosity, and greater than about 0.05 wt-% glycerol. A method of preparing a functional fluid comprising adding glycerol to a functional fluid, wherein the glycerol is not glycerol monooleate. A method of preparing an additive concentrate comprising adding glycerol to a diluent oil wherein the concentrate contains from about 1% to about 99% by weight of said diluent. A method of reducing friction comprising contacting a metal surface with a functional fluid comprising a major amount of an oil of lubricating viscosity and greater than about 0.05 wt-% glycerol.

1 . A functional fluid comprising
 a. a major amount of an oil of lubricating viscosity, and   b. greater than about 0.05 wt-% glycerol.   
     
     
         2 . The functional fluid of  claim 1  wherein the functional fluid does not contain more than 0.5 wt-% of glycerol monooleate. 
     
     
         3 . The functional fluid of  claim 1  wherein the functional fluid also contains at least one detergent. 
     
     
         4 . The functional fluid of  claim 3  wherein the detergent further comprises at least one low overbased sulfonate, at least one medium overbased sulfonate, at least one high overbased sulfonate, or at least one non-sulfonate detergent. 
     
     
         5 . The functional of  claim 4  wherein the low overbased sulfonate is a low overbased calcium sulfonate. 
     
     
         6 . The functional fluid of  claim 4  wherein the non-sulfonate detergent is at least one phenate detergent or at least one carboxylate detergent. 
     
     
         7 . The functional fluid of  claim 4  wherein the high overbased sulfonate is a high overbased calcium sulfonate. 
     
     
         8 . The functional fluid of  claim 1  wherein the functional fluid also contains at least one antiwear additive. 
     
     
         9 . The functional fluid of  claim 8  wherein the at least one antiwear additive is zinc dialkyl dithiophosphate. 
     
     
         10 . The functional fluid of  claim 9  wherein the zinc dialkyl dithiophosphate is derived from a primary alcohol. 
     
     
         11 . The functional fluid of  claim 1  wherein the functional fluid is a tractor hydraulic fluid. 
     
     
         12 . The functional fluid of  claim 1  wherein the amount of glycerol in the functional fluid is at least about 0.05 weight %. 
     
     
         13 . The functional fluid of  claim 1  wherein the amount of glycerol in the functional fluid is from about 0.05 to about 1.0 wt %. 
     
     
         14 . The functional fluid of  claim 10  wherein the amount of glycerol in the functional fluid is from about 0.1 to about 0.3 wt %. 
     
     
         15 . The functional fluid of  claim 1  wherein the functional fluid also contains a glycerol monooleate. 
     
     
         16 . A method of preparing a functional fluid comprising adding glycerol to a functional fluid, wherein the glycerol is not glycerol monooleate. 
     
     
         17 . A method of preparing an additive concentrate comprising adding glycerol to a diluent oil wherein the concentrate contains from about 1% to about 99% by weight of said diluent. 
     
     
         18 . A method of reducing friction comprising contacting a metal surface with a functional fluid comprising
 a. a major amount of an oil of lubricating viscosity and   b. greater than about 0.05 wt-% glycerol.