Lubricating oil composition

Abstract

Lubricating oil composition containing components (A)-(C) in a base oil is provided. The components (A)-(C) are (A) one or more metal detergents selected from optionally substituted divalent metal phenates, optionally substituted divalent metal salts of salicylic acid and optionally substituted divalent metal salts of sulphonic acid; (B) one or more zinc dialkyl dithiophosphates; and (C) one or more compounds selected from (i) one or more fatty acid esters, and/or (ii) one or more further phosphorus compounds.

1 . A lubricating oil composition comprising: 
 (a) a base oil comprising mineral oil, synthetic oil or mixtures thereof,    (b) at least one metal detergent selected from the group consisting of divalent metal phenates, divalent metal salts of salicylic acid, and divalent metal salts of sulphonic acid;    (c) at least one zinc dialkyl dithiophosphates; and    (d) at least one compound selected from the group consisting of 
 (i) one or more fatty acid esters, and/or  
 (ii) one or more further phosphorus compounds.  
   
   
   
       2 . The lubricating oil composition of  claim 1  wherein component d) is at least one fatty acid ester.  
   
   
       3 . The lubricating oil composition of  claim 1  wherein component d) is at least one further phosphorus compound.  
   
   
       4 . The lubricating oil composition of  claim 1  wherein component d) comprise i) at least one fatty acid ester; and ii) at least one further phosphorus compound.  
   
   
       5 . The lubricating oil composition of  claim 1  wherein the metal detergent component b) is present in a total amount in the range of from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition.  
   
   
       6 . The lubricating oil composition of  claim 1  wherein the zinc dialkyl dithiophosphates component c) is present in a total amount in the range of from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition.  
   
   
       7 . The lubricating oil composition of  claim 4  wherein the components (d)(i) and (d)(ii) are each present in an amount in the range of from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition.  
   
   
       8 . The lubricating oil composition of  claim 1  wherein it has oxidation stability such that, in a test based on the JIS K 2514 ISOT test, the increase in acid value after 96 hours at 135° C. is 0.50 mg KOH/g or less.  
   
   
       9 . The lubricating oil composition of  claim 1  wherein among the synchroniser properties, the coefficient of friction is 0.100 or more and/or the amount of wear is 0.60 mm or less.  
   
   
       10 . The lubricating oil composition of  claim 1  wherein the metal detergent component b) is divalent metal salt of salicylic acid having one or more alkyl group substituents.  
   
   
       11 . The lubricating oil composition of  claim 1  wherein the metal detergent component b) is a calcium salt of alkylphenols having at least one linear or branched 4 to 30 carbon alkyl group or calcium salts of alkylphenol sulphides.  
   
   
       12 . The lubricating oil composition of  claim 1  wherein the metal detergent component b) is a calcium salt of alkylaromatic sulphonic acid.  
   
   
       13 . The lubricating oil composition of  claim 1  wherein the component (d) is present in an amount in the range of from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition.  
   
   
       14 . A lubricating oil composition comprising: 
 (a) a base oil comprising mineral oil, synthetic oil or mixtures thereof,    (b) from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition, of at least one metal detergent selected from the group consisting of divalent metal phenates, divalent metal salts of salicylic acid, and divalent metal salts of sulphonic acid;    (c) from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition, of at least one zinc dialkyl dithiophosphates; and    (d) from 0.3 to 5.0 weight %, per 100 weight % of lubricating oil composition, of at least one compound selected from the group consisting of 
 (i) one or more fatty acid esters, and/or  
 (ii) one or more further phosphorus compounds.