Lubricating oil composition having excellent thermal stability, extreme pressure resistance and anti-wear performance

Abstract

The present invention relates to a lubricating oil composition for use in industrial oils such as hydraulic oils, bearing oils, industrial gear oils and sliding surface lubricating oils. In its broadest aspect, the present invention comprises a lubricating oil composition having a major amount of a base oil of lubricating viscosity and a minor, but effective amount, of A. at least one a compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof; B. a phosphorus acid ester and/or an amine thereof; and C. at least one compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof. The lubricating oil composition of the present invention provides excellent thermal stability, extreme pressure resistance and anti-wear performance.

What is claimed is:  
     
         1 . A lubricating oil composition comprising a major amount of a base oil of lubricating viscosity, and 
 A. 0.1 to 5.0 wt % of at least one compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof;    B. 0.01 to 1.0 wt % of a phosphorus acid ester and/or an amine thereof; and    C. 0.01 to 2.0 wt % of at least one compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof.    
     
     
         2 . A lubricating oil composition comprising a major amount of base oil of lubricating viscosity, and 
 A. 0.1 to 3.0 wt % of at least one compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof; and    B. 0.01 to 0.4 wt % of a phosphorus acid ester and/or an amine thereof; and    C. 0.01 to 1.0 wt % of the compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof.    
     
     
         3 . A lubricating oil composition comprising a major amount of a base oil of lubricating viscosity and 
 A. 0.1 to 1.0 wt % of at least one compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof;    B. 0.01 to 0.2 wt % of a phosphorus acid ester and/or an amine thereof; and    C. 0.01 to 0.4 wt % of a compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof.    
     
     
         4 . A lubricating oil composition according to  claim 1 , wherein the weight ratio of components A to B is in the range of 1:1 to 500:1.  
     
     
         5 . A lubricating oil composition according to  claim 4 , wherein the weight ratio of components A to B is in the range of 1:1 to 50:1.  
     
     
         6 . A lubricating oil composition according to  claim 5 , wherein the weight ratio of components A to B is in the range of 1:1 to 25:1.  
     
     
         7 . A lubricating oil composition according to  claim 1 , wherein the weight ratio of components B to C is in the range of 1:0.5 to 1:20.  
     
     
         8 . A lubricating oil composition according to  claim 7 , wherein the weight ratio of components B to C is in the range of 1:1 to 1:3.  
     
     
         9 . A lubricating oil composition according to  claim 8 , wherein the weight ratio of components B to C is in the range of 1:1 to 1:2.  
     
     
         10 . A lubricating oil composition according to  claim 1 , wherein the weight the total phosphorus content in the range of 50 to 5,000 mass ppm.  
     
     
         11 . A lubricating oil composition according to  claim 10 , wherein the weight the total phosphorus content in the range of 50 to 2,500 mass ppm.  
     
     
         12 . A lubricating oil composition according to  claim 11 , wherein the weight the total phosphorus content in the range of 50 to 1,000 mass ppm.  
     
     
         13 . A lubricating oil composition according to  claim 1 , wherein the base oil of lubricating viscosity has a kinematic viscosity of 5 to 900 mm 2 /s at 40° C.  
     
     
         14 . A lubricating oil composition according to  claim 1 , wherein the compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof is a phosphoric acid ester.  
     
     
         15 . A lubricating oil composition according to  claim 14 , wherein the phosphoric acid ester is a trialkylphenyl phosphate.  
     
     
         16 . A lubricating oil composition according to  claim 1 , wherein the phosphorus acid ester and/or an amine thereof is a dialkyl phosphite or a trialkyl phosphite.  
     
     
         17 . The lubricating oil composition according to  claim 1 , wherein the compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof is an alkyl succinic acid ester.  
     
     
         18 . The lubricating oil composition according to  claim 17 , wherein the alkyl succinic acid ester is a polybutenyl succinic acid ester.  
     
     
         19 . A lubricating oil concentrate comprising 1.0 to 30 wt % of a compatible organic diluent and 
 A. 10 to 90 wt % of at least one compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof;    B. 1 to 20 wt % of a phosphorus acid ester and/or an amine thereof; and    C. 1 to 40 wt % of at least one compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof.    
     
     
         20 . A lubricating oil concentrate according to  claim 19 , wherein the weight ratio of components A to B is in the range of 1:1 to 500:1.  
     
     
         21 . A lubricating oil concentrate according to  claim 20 , wherein the weight ratio of components A to B is in the range of 1:1 to 50:1.  
     
     
         22 . A lubricating oil concentrate according to  claim 21 , wherein the weight ratio of components A to B is in the range of 1:1 to 25:1.  
     
     
         23 . A lubricating oil concentrate according to  claim 19 , wherein the weight ratio of components B to C is in the range of 1:0.5 to 1:20.  
     
     
         24 . A lubricating oil concentrate according to  claim 23 , wherein the weight ratio of components B to C is in the range of 1:1 to 1:3.  
     
     
         25 . A lubricating oil concentrate according to  claim 24 , wherein the weight ratio of components B to C is in the range of 1:1 to 1:2.  
     
     
         26 . A lubricating oil concentrate according to  claim 19 , wherein the weight the total phosphorus content in the range of 5,000 to 80,000 mass ppm.  
     
     
         27 . A lubricating oil concentrate according to  claim 19 , wherein the weight the total phosphorus content in the range of 10,000 to 50,000 mass ppm.  
     
     
         28 . A lubricating oil concentrate according to  claim 27 , wherein the weight the total phosphorus content in the range of 15,000 to 30,000 mass ppm.  
     
     
         29 . A lubricating oil concentrate according to  claim 19 , wherein the compound selected from the group consisting of a phosphoric acid ester, a thiophosphoric acid ester, and amine salts thereof is a phosphoric acid ester.  
     
     
         30 . A lubricating oil concentrate according to  claim 29 , wherein the phosphoric acid ester is a trialkylphenyl phosphate.  
     
     
         31 . A lubricating oil concentrate according to  claim 19 , wherein the phosphorus acid ester and/or an amine thereof is a dialkyl phosphite or a trialkyl phosphite.  
     
     
         32 . The lubricating oil concentrate according to  claim 19 , wherein the compound selected from the group consisting of an alkenyl succinimide, an alkenyl succinic acid ester, benzylamine, and derivatives thereof is an alkenyl succinic acid ester.  
     
     
         33 . The lubricating oil concentrate according to  claim 32 , wherein the alkenyl succinic acid ester is a polybutenyl succinic acid ester.  
     
     
         34 . A method for producing a lubricating oil composition comprising blending the components according to  claim 1 .  
     
     
         35 . A lubricating oil composition produced by the method according to  claim 34 .  
     
     
         36 . A method for lubricating hydraulic systems, bearing systems, gear systems, or sliding systems with the lubricating oil composition of claim  1 .