Multipurpose lubricant based on phosphorous and sulphur compounds

Abstract

The multifunctional lubricant according to the invention comprises at least one phosphoric ester (A) of general formula: in which k is equal to 2 or 3, m is a number ranging from 0 to 8, x is equal to 1 or 2 and R represents a linear alkyl or alkenyl radical having from 10 to 20 carbon atoms, or a salt of such an ester and at least one polysulphide (B) of general formula: R′—S y —R′ in which y is a number ranging from 2 to 8 and R′ represents a tert-alkyl radical having from 4 to 18 carbon atoms, the A/B ratio by mass being between 0.01/1 and 1/1.

1 . Multifunctional lubricant comprising at least one phosphorus compound (A) and at least one sulphur compound (B), characterized in that the compound A is a phosphoric ester of general formula:  
       
         
           
           
               
               
           
         
       
       in which k is equal to 2 or 3, m is a number ranging from 0 to 8, x is equal to 1 or 2 and R represents a linear alkyl or alkenyl radical having from 10 to 20 carbon atoms, or a salt of such an ester and the compound B is a polysulphide of general formula:  
       R′—S y —R′ 
       in which y is a number ranging from 2 to 8 and R′ represents a tert-alkyl radical having from 4 to 18 carbon atoms, the a/b ratio by mass being between 0.01/1 and 1/1.  
     
     
         2 . Lubricant according to  claim 1 , in which k is equal to 2, m is a number ranging from 2 to 6 and R is a radical having from 12 to 18 carbon atoms.  
     
     
         3 . Lubricant according to  claim 1  or  2 , in which the number y is between 3 and 5 and R′ is a tert-alkyl radical having from 4 to 12 carbon atoms.  
     
     
         4 . Lubricant according to one of  claims 1  to  3 , in which the A/B ratio by mass is between 0.05/1 and 0.4/1.  
     
     
         5 . Lubricant according to one of  claims 1  to  4 , in which the compound A is a mixture of phosphoric mono- and diesters, the number k being equal to 2, the number m being between 4 and 5 and R being the lauryl, stearyl, oleyl or linoleyl radical.  
     
     
         6 . Lubricant according to one of  claims 1  to  5 , in which the compound B is di-tert-butyl trisulphide, di-tert-nonyl pentasulphide, di-tert-dodecyl trisulphide or di-tert-dodecyl pentasulphide.  
     
     
         7 . Multifunctional lubricant additive, characterized in that it comprises at least one phosphoric ester (A) of general formula:  
       
         
           
           
               
               
           
         
       
       in which k is equal to 2 or 3, m is a number ranging from 0 to 8, x is equal to 1 or 2 and R represents a linear alkyl or alkenyl radical having from 10 to 20 carbon atoms, or a salt of such an ester and at least one polysulphide (B) of general formula:  
       R′—S y —R′ 
       in which y is a number ranging from 2 to 8 and R′ represents a tert-alkyl radical having from 4 to 18 carbon atoms, the A/B ratio by mass being between 0.01/1 and 1/1.  
     
     
         8 . Additive according to  claim 7 , in which k is equal to 2, m is a number ranging from 2 to 6 and R is a radical having from 12 to 18 carbon atoms.  
     
     
         9 . Additive according to  claim 7  or  8 , in which the number y is between 3 and 5 and R′ is a tert-alkyl radical having from 4 to 12 carbon atoms.  
     
     
         10 . Additive according to one of  claims 7  to  9 , in which the A/B ratio by mass is between 0.05/1 and 0.4/1.  
     
     
         11 . Additive according to one of claims  7  to  10 , in which the compound A is a mixture of phosphoric mono- and diesters, the number k being equal to 2, the number m being between 4 and 5 and R being the lauryl, stearyl, oleyl or linoleyl radical.  
     
     
         12 . Additive according to one of  claims 7  to  11 , in which the compound B is di-tert-butyl trisulphide, di-tert-nonyl pentasulphide, di-tert-dodecyl trisulphide or di-tert-dodecyl pentasulphide.