Toxicologically acceptable alkylphenol detergents as friction modifiers in automotive lubricating oils

Abstract

The disclosed technology relates to the use of toxicologically acceptable hydrocarbyl- (e.g. alkyl-) phenol detergents and their salts in automotive lubricating oils, such as, for example, automatic or manual transmissions.

1 . A transmission lubricant composition comprising
 a. an oil of lubricating viscosity,   b. from about 0.1 to about 5 wt % of a dispersant, and   c. from about 0.1 to about 5 wt % of a detergent, wherein from about 0.01 to about 2 wt % of the detergent comprises an alkylphenol detergent comprising at least one unit of an alkyl-substituted phenol wherein the alkyl group is derived from oligomers of an olefin compound containing 3 to 8 carbon atoms, wherein the olefin-derived alkyl group comprises at least 30 mol percent of oligomers derived from n-butane, and where the alkyl group is a hydrocarbyl group of 12 to 48 carbon atoms, and   d. from about 0.05 to about 3 wt % of a C 2 -C 18  di- or tri-hydrocarbyl phosphite, based on the total weight of said lubricant   wherein all wt % are based on a total weight of said lubricant composition.   
     
     
         2 . The lubricant of  claim 1 , wherein the alkylphenol detergent is a sulfur-bridged phenate, a sulfur-free alkylene-bridged phenate, a salicylate, or mixtures thereof. 
     
     
         3 . The lubricant of  claim 2 , wherein the alkylphenol detergent comprises one or more alkali metals, one or more alkaline earth metals, or mixtures thereof. 
     
     
         4 . The lubricant of  claim 3 , wherein the alkylphenol detergent is overbased. 
     
     
         5 . The lubricant of  claim 4 , where the overbased alkylphenol detergent has a metal ratio of at least 1.5, at least 5, or at least 7. 
     
     
         6 . (canceled) 
     
     
         7 . The lubricant of  claim 1 , wherein the alkylphenol detergent is an overbased sulfur-coupled alkylphenol detergent with a metal ratio of at least 1.5. 
     
     
         8 . The lubricant of  claim 1 , wherein the alkylphenol detergent comprises a sulfur-bridged phenate represented by the structure 
       
         
           
           
               
               
           
         
       
       wherein each R is an aliphatic hydrocarbyl group derived from oligomers of n-butene, higher alphaolefins, or mixtures thereof, that contains 8 to 48 carbon atoms; y is 1 to 4; and n=0 to 8, or 1 to 6, or 1 to 4, or 2 to 4. 
     
     
         9 . The lubricant of  claim 1 , wherein the alkylphenol detergent is a neutral or overbased salt of alkylsalicylic acid. 
     
     
         10 . The lubricant of  claim 1 , wherein the alkylphenol detergent is an alkyl salicylate represented by the structure 
       
         
           
           
               
               
           
         
       
       where R is an aliphatic hydrocarbyl group derived from oligomers of n-butene, higher alphaolefins, or mixtures thereof, and wherein the hydrocarbyl group contains 8 to 48 carbon atoms 
     
     
         11 . The lubricant of  claim 1 , wherein the oil of lubricating viscosity comprises at least one API Group I, II, III, IV, or V, lubricant or mixtures thereof. 
     
     
         12 . The lubricant of  claim 1  further comprising at least one of a phosphorus-containing antiwear agent comprising a non-ionic phosphorus compound; an amine salt of a phosphorus compound; a calcium-containing detergent; another phenate detergent; a sulphur-containing extreme pressure agent; a sulphur-containing corrosion inhibitor; or combinations thereof. 
     
     
         13 . (canceled) 
     
     
         14 . The lubricant of  claim 1  further comprising less than 2000 ppm zinc based on a total weight of said lubricant. 
     
     
         15 . The lubricant of  claim 1 , wherein the lubricant is substantially free of to free of a phenol alkylated with oligomers of propylene. 
     
     
         16 . A method of lubricating a manual transmission comprising supplying to said manual transmission a lubricant composition comprising
 a. an oil of lubricating viscosity,   b. from about 0.1 to about 5 wt % of a dispersant, and   c. about 0.01 to about 2 wt % of the detergent comprises an alkylphenol detergent comprising at least one unit of an alkyl-substituted phenol wherein the alkyl group is derived from oligomers of an olefin compound containing 3 to 8 carbon atoms, wherein the olefin-derived alkyl group comprises at least 30 mol percent of an olefin with 4 or more carbon atoms where all wat % are based on a total weight of said lubricant composition.   
     
     
         17 . The method of  claim 16 , wherein the lubricant composition comprises:
 a. the oil of lubricating viscosity;   b. a thiadiazole;   c. a phosphorous containing antiwear agent   d. the dispersant;   e. the detergent; and   f. the alkylphenol detergent.   
     
     
         18 . A method of lubricating automatic transmission comprising supplying the lubricant composition of  claim 1  to said automatic transmission. 
     
     
         19 . The method of  claim 18 , wherein the lubricant composition comprises:
 a. the oil of lubricating viscosity;   b. a thiadiazole;   c. a phosphorous containing antiwear agent   d. the dispersant;   e. the detergent; and   f. the alkylphenol detergent.   
     
     
         20 . A method of lubricating an off-highway vehicle comprising supplying the lubricant composition of  claim 1  to said off-highway vehicle. 
     
     
         21 . The method of  claim 20 , wherein the lubricant composition comprises:
 a. the oil of lubricating viscosity;   b. a zinc dialkyl dithiophosphate antiwear agent   c. the dispersant; and   d. the detergent.   
     
     
         22 . The method of  claim 20 , wherein the vehicle is a farm-tractor vehicle or a construction vehicle. 
     
     
         23 . A method of lubricating a highway vehicle comprising supplying the lubricant composition of  claim 1  to  15  to said highway vehicle. 
     
     
         24 . The method of  claim 23 , wherein the lubricant composition comprises
 a. the oil of lubricating viscosity;   b. the dispersant;   c. the detergent;   d. a sulfurized olefin;   e. a thiadiazole; and   f. a phosphorous containing antiwear agent.