Synthetic industrial oils made with "tri-synthetic" base stocks

Abstract

This invention describes a blend of three base stock fluids, a PAO, an alkylated aromatic and a aromatic ester that synergistically improve the solvency for industrial lubricant additives such as oxidation and rust inhibitors, extreme-pressure/antiwear agents, metal deactivators and the like. The blend also has excellent hydrolytic stability plus improved dispersancy and resistance to deposit formation without degrading demulsibility.

What is claimed is:  
     
         1 . A lubricant base stock blend comprising: 
 about 10 wt % or more of a polyalpha olefin (PAO) fluid;    about 1 wt % or more of an akylated aromatic fluid; and    about 1 wt % or more of an aromatic ester;    all amounts based on the weight of the blend.    
     
     
         2 . The blend of  claim 1  comprising: 
 from about 10 wt % to about 98 wt % of a PAO fluid;  
 from about 1 wt % to about 59 wt % of an alkylated aromatic fluid; and  
 from about 1 wt % to about 75 wt % of an aromatic ester.  
 
     
     
         3 . The blend of  claim 2  wherein the PAO comprise from about 80 to 85 wt %.  
     
     
         4 . The blend of  claim 2  wherein the alkylated aromatic comprises about 10 wt %.  
     
     
         5 . The blend of  claim 2  wherein the ester comprises from about 5 to about 8 wt %.  
     
     
         6 . The blend of  claim 1  or  2  wherein the alkylated aromatic is an alkylated naphthalene having 1 or more alkyl group of from 1 to about 8 carbon atoms.  
     
     
         7 . The blend of  claim 1  or  3  wherein the aromatic ester is the product of an aromatic acid or acid anhydride and a straight or branched aliphatic alcohol of from 3 to 18 carbon atoms.  
     
     
         8 . The ester of  claim 7  wherein the aromatic acid or anhyride is phthalic acid or anhydride.  
     
     
         9 . A lubricant composition comprising: 
 a major amount of a lubricant base stock blend; and    an effective amount of at least one lubricant additive selected from the group consisting of antioxidants, rust inhibitors, extreme pressure agents, and metal deactivators;    the base stock blend comprising about 10 wt % or more of a polyalpha olefin fluid;    about 1 wt % or more of an alkylated aromatic fluid; and    about 1 wt % or more of an aromatic ester,    the amounts in the blend being based on the weight of the blend.    
     
     
         10 . The composition of  claim 9  wherein the blend comprises: 
 from about 10 wt % to about 98 wt % of a PAO fluid;  
 from about 1 wt % to about 59 wt % of an alkylated aromatic fluid; and  
 from about 1 wt % to about 75 wt % of an aromatic ester.