Oil-Based Lubricant Especially Useful for Precision Parts

Abstract

A lubricant composition contains about 2 to 10 weight percent (wt. %) of tungsten disulfide; about 2 to 10 (wt. %) of a zinc dialkyl dithiophosphates (ZDDP); and an oil carrier.

What is claimed is: 
     
         1 . A lubricant composition comprising about 2 to 10 weight percent (wt. %) of tungsten disulfide; about 2 to 10 (wt. %) of a zinc dialkyl dithiophosphates (ZDDP); and an oil carrier. 
     
     
         2 . The lubricant of  claim 1  wherein the oil carrier is an ester oil. 
     
     
         3 . The lubricant of  claim 2  wherein the synthetic ester oil is a polyol ester oil. 
     
     
         4 . The lubricant of  claim 3  wherein the polyol ester oil has a viscosity at 40° C. of about 6 cSt to about 30 cSt. 
     
     
         5 . The lubricant of  claim 4  wherein the polyol ester oil has a viscosity at 40° C. of about 8 cSt to about 25 cSt. 
     
     
         6 . The lubricant of  claim 5  wherein the polyol ester oil has a viscosity index of about 110 to about 200. 
     
     
         7 . The lubricant of  claim 6  wherein the polyol ester oil has a viscosity index of about 115 to 150. 
     
     
         8 . The lubricant of  claim 7  wherein the polyol ester oil has a viscosity index of about 115 to 140. 
     
     
         9 . The lubricant of  claim 8  wherein the wt % of tungsten disulfide is about 2% to about 5%. 
     
     
         10 . The lubricant of  claim 9  wherein the wt % of ZDDP is about 2% to 5% 
     
     
         11 . The lubricant of  claim 10  wherein the wt % of ZDDP is about 4%. 
     
     
         12 . The lubricant of  claim 11  wherein the tungsten disulfide is a fullerene-shaped tungsten disulfide. 
     
     
         13 . The lubricant of  claim 12  wherein the tungsten disulfide has a particle size of about 200 nm to about 600 nm. 
     
     
         14 . The lubricant of  claim 13  wherein the wt % of tungsten disulfide is about 4%. 
     
     
         15 . The lubricant of  claim 14  wherein about 25% of the tungsten disulfide has a particle size of 200 nm, about 25% of the tungsten disulfide has a particle size of about 400 nm, and about 50% of the tungsten disulfide has particle size of about 600 nm. 
     
     
         16 . The lubricant of  claim 1  wherein the lubricant is a chain lubricant. 
     
     
         17 . The lubricant of  claim 1  further comprising a up to 3% of a calcium sulfonate oil additive. 
     
     
         18 . The lubricant of  claim 17  comprising about 2% of a calcium sulfonate oil additive. 
     
     
         19 . A method of manufacturing the lubricant of  claim 1 , the method comprising: contacting a tungsten disulfide, ZDDP, and an oil carrier under conditions effective to disperse the tungsten disulfide and ZDDP in the oil carrier to manufacture the lubricant.