Lubricating oil composition

Abstract

The present invention provides a lubricating oil composition comprising a base oil, an aspartic acid derivative and an aliphatic amine compound. The lubricating oil composition is ideal as an industrial lubricating oil such as for example for a hydraulic working oil in hydraulic equipment. Primary amine, secondary amine, diamine, and/or tertiary amines may be employed for the aliphatic amine compound.

1 - 13 . (canceled) 
   
   
       14 . A lubricating oil composition comprising a base oil, an aspartic acid derivative, and an aliphatic amine compound. 
   
   
       15 . The lubricating oil composition of  claim 14 , wherein the aspartic acid derivative has an acid value of that is at least 10 and no greater than 200 mg KOH/g. 
   
   
       16 . The lubricating oil composition of  claim 14 , wherein the aspartic acid derivative is at an amount that is at least about 0.01 and no greater than about 5 weight % of the lubricating oil composition and the aliphatic amine compound is at an amount that is at least about 0.005 and no greater than about 5 weight % of the lubricating oil composition 
   
   
       17 . The lubricating oil composition of  claim 14 , wherein the aliphatic amine compound comprises a primary amine represented by the formula H 2 N—X 5  where X 5  is an alkyl group or alkenyl group of carbon number 1 to 30. 
   
   
       18 . The lubricating oil composition of  claim 14 , wherein the aliphatic amine compound further comprises a secondary amine represented by the formula X 6 —NH—X 7  where X 6  and X 7  are an alkyl group or alkenyl group of carbon number 1 to 30. 
   
   
       19 . The lubricating oil composition of  claim 14 , wherein the aliphatic amine compound comprises a diamine represented by the formula X 8 —NH—X 9 —NH 2  where X 5  is an alkyl group or alkenyl group of carbon number 1 to 30 and X 9  is an alkylene group of carbon number 1 to 12. 
   
   
       20 . The lubricating oil composition of  claim 14  wherein the aliphatic amine compound comprises a tertiary amine represented by the formula X 10 —NH—(X 11 ) 2  where X 10  is an alkyl group or alkenyl group of carbon number 1 to 30 and X 11  is an alkyl group, alkenyl group, or hydroxyalkyl group of carbon number 1 to 20. 
   
   
       21 . The lubricating oil composition of  claim 14  further comprising an aromatic amine compound, a phenol compound, or both. 
   
   
       22 . The lubricating oil composition of  claim 14 , wherein said base oil is a synthetic oil. 
   
   
       23 . The lubricating oil composition of  claim 22 , wherein said synthetic oil is a poly-α-olefin or GTL. 
   
   
       24 . A lubricating oil composition comprising a base oil, an aspartic acid derivative at an amount that is at least about 0.01 and no greater than about 5 weight % of the lubricating oil composition, and an aliphatic amine compound at an amount that is at least about 0.005 and no greater than about 5 weight % of the lubricating oil composition, wherein the aspartic acid derivative has an acid value that is at least 10 and no greater than 200 mg KOH/g, and wherein the aliphatic amine compound comprises: a primary amine represented by the formula H 2 N—X 8  where X 5  is an alkyl group or alkenyl group of carbon number 1 to 30; a secondary amine represented by the formula X 6 —NH—X 7  where X 6  and X 7  are an alkyl group or alkenyl group of carbon number 1 to 30; a diamine represented by the formula X 8 —NH—X 9 —NH 2  where X 8  is an alkyl group or alkenyl group of carbon number 1 to 30 and X 9  is an alkylene group of carbon number 1 to 12; and a tertiary amine represented by the formula X 10 —NH—(X 11 ) 2  where X 10  is an alkyl group or alkenyl group of carbon number 1 to 30 and X 11  is an alkyl group, alkenyl group, or hydroxyalkyl group of carbon number 1 to 20. 
   
   
       25 . A method of lubricating an apparatus, the method comprising lubricating the apparatus with a lubricating oil composition that comprises a base oil, an aspartic acid derivative, and an aliphatic amine compound. 
   
   
       26 . The method of  claim 25 , wherein the aspartic acid derivative has an acid value of that is at least 10 and no greater than 200 mg KOH/g. 
   
   
       27 . The method of  claim 25 , wherein the aspartic acid derivative is at an amount that is at least about 0.01 and no greater than about 5 weight % of the lubricating oil composition and the aliphatic amine compound is at an amount that is at least about 0.005 and no greater than about 5 weight % of the lubricating oil composition 
   
   
       28 . The method of  claim 25 , wherein the aliphatic amine compound comprises a primary amine represented by the formula H 2 N—X 5  where X 5  is an alkyl group or alkenyl group of carbon number 1 to 30. 
   
   
       29 . The method of  claim 25 , wherein the aliphatic amine compound further comprises a secondary amine represented by the formula X 6 —NH—X 7  where X 6  and X 7  are an alkyl group or alkenyl group of carbon number 1 to 30. 
   
   
       30 . The method of  claim 25 , wherein the aliphatic amine compound comprises a diamine represented by the formula X 8 —NH—X 9 —NH 2  where X 8  is an alkyl group or alkenyl group of carbon number 1 to 30 and X 9  is an alkylene group of carbon number 1 to 12. 
   
   
       31 . The method of  claim 25  wherein the aliphatic amine compound comprises a tertiary amine represented by the formula X 10 —NH—(X 11 ) 2  where X 10  is an alkyl group or alkenyl group of carbon number 1 to 30 and X 11  is an alkyl group, alkenyl group, or hydroxyalkyl group of carbon number 1 to 20. 
   
   
       32 . The method of  claim 25 , wherein the lubricating oil composition further comprises an aromatic amine compound, a phenol compound, or both. 
   
   
       33 . The method of  claim 25 , wherein said base oil is a synthetic oil. 
   
   
       34 . The method of  claim 33 , wherein said synthetic oil is a poly-α-olefin or GTL.