Oil additive

Abstract

The present disclosure relates to the use of a C 12-20 polyalkyl methacrylate polymer as a lubricating oil additive such that the C 12-20 polyalkyl methacrylate polymer accounts for 0.1 to 0.3% by weight of the finished lubricating oil. The use comprises the addition of said C 12-20 polyalkyl methacrylate polymer to a lubricating oil based on mineral oil to improve the filtration of said lubricating oil based on mineral oil. Further, the present disclosure relates to finished lubricating oils resulting from such a use and methods of lubricating the metal surface of a gear or axle comprising applying to the metal surface such a finished lubricating oil.

1 . Use of a C 12-20  polyalkyl methacrylate polymer as a lubricating oil additive such that the C 12-20  polyalkyl methacrylate polymer accounts for 0.1 to 0.3% by weight of the finished lubricating oil, which use comprises the addition of said C 12-20  polyalkyl methacrylate polymer to a lubricating oil based on mineral oil to improve the filtration of said lubricating oil based on mineral oil.  
   
   
       2 . Use according to  claim 1  wherein the lubricating oil based on mineral oil is a gear oil.  
   
   
       3 . Use according to  claim 1  wherein the mean CETOP filtration stage 2 test value of the finished lubricating oil (the oil resulting from said use) is over 90%.  
   
   
       4 . Use according to  claim 3  wherein the finished lubricating oil (the oil resulting from said use) meets the specification by Scania (STO 1:0).  
   
   
       5 . Use according to  claim 1  wherein the C 1220  polyalkyl methacrylate polymer accounts for 0.1 or 0.2% by weight of the finished lubricating oil.  
   
   
       6 . Use according to  claim 1  of a composition comprising the C 12-20  polyalkyl methacrylate polymer.  
   
   
       7 . Use according to  claim 6  wherein the composition comprises about 45% by weight of the C 12-20  polyalkyl methacrylate polymer and about 55% by weight of a mineral carrier oil.  
   
   
       8 . Use according to  claim 7  wherein the composition has a viscosity of 800 mm 2 /s (ASTM D4052) at 100° C.  
   
   
       9 . Use according to  claim 1  wherein the lubricating oil based on mineral oil has a viscosity of 80W-90 or 85W-140.  
   
   
       10 . Use according to  claim 1  wherein the lubricating oil based on mineral oil is for automotive or industrial applications.  
   
   
       11 . Use according to  claim 1  wherein the lubricating oil based on mineral oil is a part synthetic base stock.  
   
   
       12 . Use according to  claim 1  wherein the lubricating oil based on mineral oil comprises brightstock.  
   
   
       13 . Use according to  claim 1  wherein the lubricating oil based on mineral oil is Kuwait Petroleum Company, Repsol YPF, Total, Esso or SAFOR base stock.  
   
   
       14 . Use according to  claim 1  wherein the lubricating oil based on mineral oil and/or the finished lubricating oil comprises a further additive, which further additive is added to the lubricating oil based on mineral oil or the finished lubricating oil prior to, simultaneously with or subsequently to the composition comprising a C 12-20  polyalkyl methacrylate polymer in a mineral carrier oil.  
   
   
       15 . Use according to  claim 1  wherein the lubricating oil based on mineral oil is a formulated gear lubricant composition.  
   
   
       16 . A finished lubricating oil resulting from a use as defined in  claim 1 .  
   
   
       17 . A method of lubricating the metal surface of a gear or axle comprising applying to the metal surface a finished lubricating oil as defined in  claim 16 .  
   
   
       18 . A method according to  claim 17  wherein the method comprises adding the finished lubricating oil to a transmission or axle and operating the transmission or axle.  
   
   
       19 . A gear or axle which has been lubricated in a method according to  claim 17 .  
   
   
       20 . A composition comprising a C 12-20  polyalkyl methacrylate polymer in a mineral carrier oil for use as defined in  claim 1 .  
   
   
       21 . A gear additive package comprising a composition as defined in  claim 20.