Lubricating oil compositions having improved cleanliness and wear performance

Abstract

A method for improving wear protection, while maintaining or improving deposit control and cleanliness, in an engine or other mechanical component lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and one or more lubricating oil additives including at least one borated detergent, as a minor component. The at least one borated detergent comprises a borated alkaline earth metal sulfonate. The borated alkaline earth metal sulfonate is present in an amount sufficient to provide a total boron concentration of about 300 parts per million or greater in the formulated oil. Wear protection is improved, and deposit control and cleanliness are maintained or improved, as compared to wear protection, deposit control and cleanliness achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate.

1 . A method for improving wear protection, while maintaining or improving deposit control and cleanliness, in an engine or other mechanical component lubricated with a lubricating oil by using as the lubricating oil a formulated oil, said formulated oil having a composition comprising a lubricating oil base stock as a major component; and one or more lubricating oil additives, as a minor component;
 wherein the one or more lubricating oil additives comprise at least one borated detergent;   wherein the at least one borated detergent comprises a borated alkaline earth metal sulfonate;   wherein the borated alkaline earth metal sulfonate is present in an amount sufficient to provide a total boron concentration of about 300 parts per million or greater in the formulated oil; and   wherein wear protection is improved, and deposit control and cleanliness are maintained or improved, as compared to wear protection, deposit control and cleanliness achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate.   
     
     
         2 . The method of  claim 1  wherein, in wear measurements of the lubricating oil by a Sequence IVB engine test, intake lifter wear (mm 3 ) is improved as compared to intake lifter wear (mm 3 ) achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate. 
     
     
         3 . The method of  claim 1  wherein, in deposit measurements of the lubricating oil by thermo-oxidation engine oil simulation (TEOST 33C) measured by ASTM D6335, the amount of total deposits is maintained or reduced as compared to the amount of total deposits in a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate. 
     
     
         4 . The method of  claim 1  wherein wear control is improved and deposit, varnish and sludge control, and fuel efficiency are maintained or improved as compared to wear control, deposit, varnish and sludge control, and fuel efficiency achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate. 
     
     
         5 . The method of  claim 1  wherein, in deposit measurements of the lubricating oil by thermo-oxidation engine oil simulation (TEOST 33C) measured by ASTM D6335, the amount of total deposits is less than about 30 mg. 
     
     
         6 . The method of  claim 1  wherein the borated alkaline earth metal sulfonate detergent comprises borated calcium sulfonate. 
     
     
         7 . The method of  claim 1  wherein the borated alkaline earth metal sulfonate is present in an amount sufficient to provide a total boron concentration of about 350 parts per million or greater, or about 400 parts per million or greater, or about 450 parts per million or greater, or about 500 parts per million or greater, or about 550 parts per million or greater, or about 600 parts per million or greater, or about 650 parts per million or greater, or about 700 parts per million or greater, or about 750 parts per million or greater, or about 800 parts per million or greater, or about 850 parts per million or greater, or about 900 parts per million or greater, or about 950 parts per million or greater, or about 1000 parts per million or greater, in the formulated oil. 
     
     
         8 . The method of  claim 1  wherein the one or more lubricating oil additives further comprise an alkaline earth metal sulfonate detergent system or a mixed alkaline earth metal sulfonate detergent system. 
     
     
         9 . The method of  claim 8  wherein the mixed alkaline earth metal sulfonate detergent system comprises a calcium/magnesium sulfonate detergent system. 
     
     
         10 . The method of  claim 1  wherein the total amount of soap delivered by the at least one borated detergent is less than about 1.0 weight percent of the lubricating oil. 
     
     
         11 . The method of  claim 1  wherein the lubricating oil base stock comprises a Group I, Group II, Group III, Group IV or Group V base oil. 
     
     
         12 . The method of  claim 1  wherein the at least one borated detergent is present in an amount of from about 0.001 weight percent to about 20 weight percent, based on the total weight of the formulated oil. 
     
     
         13 . The method of  claim 1  wherein the lubricating oil base stock is present in an amount of from about 6 weight percent to about 95 weight percent, based on the total weight of the formulated oil. 
     
     
         14 . The method of  claim 1  wherein the one or more lubricating oil additives further comprise one or more of an antiwear additive, viscosity modifier, antioxidant, other detergent, dispersant, pour point depressant, corrosion inhibitor, metal deactivator, seal compatibility additive, anti-foam agent, inhibitor, friction modifier, and anti-rust additive. 
     
     
         15 . The method of  claim 1  wherein the lubricating oil is a passenger vehicle engine oil (PVEO). 
     
     
         16 . A lubricating oil composition comprising a lubricating oil base stock as a major component, and one or more lubricating oil additives, as a minor component;
 wherein the one or more lubricating oil additives comprise at least one borated detergent;   wherein the at least one borated detergent comprises a borated alkaline earth metal sulfonate;   wherein the borated alkaline earth metal sulfonate is present in an amount sufficient to provide a total boron concentration of about 300 parts per million or greater in the lubricating oil; and   wherein wear protection is improved, and deposit control and cleanliness are maintained or improved, in an engine or other mechanical component lubricated with the lubricating oil, as compared to wear protection, deposit control and cleanliness achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate.   
     
     
         17 . The lubricating oil composition of  claim 16  wherein, in wear measurements of the lubricating oil by a Sequence IVB engine test, intake lifter wear (mm 3 ) is improved as compared to intake lifter wear (mm 3 ) achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate. 
     
     
         18 . The lubricating oil composition of  claim 16  wherein, in deposit measurements of the lubricating oil by thermo-oxidation engine oil simulation (TEOST 33C) measured by ASTM D6335, the amount of total deposits is maintained or reduced as compared to the amount of total deposits in a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate. 
     
     
         19 . The lubricating oil composition of  claim 16  wherein wear control is improved and deposit, varnish and sludge control, and fuel efficiency are maintained or improved as compared to wear control, deposit, varnish and sludge control, and fuel efficiency achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate. 
     
     
         20 . The lubricating oil composition of  claim 16  wherein, in deposit measurements of the lubricating oil by thermo-oxidation engine oil simulation (TEOST 33C) measured by ASTM D6335, the amount of total deposits is less than about 30 mg. 
     
     
         21 . The lubricating oil composition of  claim 16  wherein the borated alkaline earth metal sulfonate detergent comprises borated calcium sulfonate. 
     
     
         22 . The lubricating oil composition of  claim 16  wherein the borated alkaline earth metal sulfonate is present in an amount sufficient to provide a total boron concentration of about 350 parts per million or greater, or about 400 parts per million or greater, or about 450 parts per million or greater, or about 500 parts per million or greater, or about 550 parts per million or greater, or about 600 parts per million or greater, or about 650 parts per million or greater, or about 700 parts per million or greater, or about 750 parts per million or greater, or about 800 parts per million or greater, or about 850 parts per million or greater, or about 900 parts per million or greater, or about 950 parts per million or greater, or about 1000 parts per million or greater, in the lubricating oil. 
     
     
         23 . The lubricating oil composition of  claim 16  wherein the one or more lubricating oil additives further comprise an alkaline earth metal sulfonate detergent system or a mixed alkaline earth metal sulfonate detergent system. 
     
     
         24 . The lubricating oil composition of  claim 23  wherein the mixed alkaline earth metal sulfonate detergent system comprises a calcium/magnesium sulfonate detergent system. 
     
     
         25 . The lubricating oil composition of  claim 16  wherein the total amount of soap delivered by the at least one borated detergent is less than about 1.5 weight percent of the lubricating oil. 
     
     
         26 . The lubricating oil composition of  claim 16  wherein the lubricating oil base stock comprises a Group I, Group II, Group III, Group IV or Group V base oil. 
     
     
         27 . The lubricating oil composition of  claim 16  wherein the at least one borated detergent is present in an amount of from about 0.001 weight percent to about 20 weight percent, based on the total weight of the lubricating oil. 
     
     
         28 . The lubricating oil composition of  claim 16  wherein the lubricating oil base stock is present in an amount of from about 6 weight percent to about 95 weight percent, based on the total weight of the lubricating oil. 
     
     
         29 . The lubricating oil composition of  claim 16  wherein the one or more lubricating oil additives further comprise one or more of an antiwear additive, viscosity modifier, antioxidant, other detergent, dispersant, pour point depressant, corrosion inhibitor, metal deactivator, seal compatibility additive, anti-foam agent, inhibitor, friction modifier, and anti-rust additive. 
     
     
         30 . The lubricating oil composition of  claim 16  which is a passenger vehicle engine oil (PVEO).