Use of specific base oil for reducing particulate emissions

Abstract

The present application relates to the use of a lubricant composition comprising a base oil or a base oil mixture having a viscosity (BOV or base oil viscosity) of less than or equal to 4, for reducing the particulate emissions of an engine. The present application relates to the use of a lubricant composition comprising a base oil or a mixture of base oils, for reducing the particulate emissions of an engine, in which said base oil or said mixture of base oils has a kinematic viscosity, measured at 100° C., of less than or equal to 4.5 mm 2 /s, and in which said lubricant composition has a viscosity at 150° C. and under constant shear of greater than or equal to 2.4 mPa.s −1 .

1 . A method for reducing the emissions of particles in an engine, comprising the lubrication of said engine with a lubricating composition comprising a base oil or a mixture of base oils, wherein said base oil or said mixture of base oils has a kinematic viscosity (BOV or base oil viscosity) measured at 100°° C. as per the standard ASTM D445, of less than or equal to 4.5 mm 2 /s. 
     
     
         2 . The method according to  claim 1 , wherein the base oil or the mixture of base oils has a kinematic viscosity (BOV or base oil viscosity) measured at 100°° C., as per the standard ASTM D445, of less than or equal to 4.5 mm 2 /s, and wherein said lubricating composition has a viscosity at 150° C. and under constant shear of greater than or equal to 2.4 mPa.s −1 . 
     
     
         3 . The method according to  claim 1 , wherein the viscosity index of the base oil or of the mixture of base oils is greater than or equal to 130. 
     
     
         4 . The method according to  claim 1 , wherein the particles have a size less than or equal to 10 nm. 
     
     
         5 . The method according to  claim 1 , wherein the kinematic viscosity, measured at 100° C., of the base oil or of the mixture of base oils is comprised between 1.5 and 4.5 mm 2 /s. 
     
     
         6 . The method according to  claim 1 , wherein the viscosity at 150° C., and under constant shear, of the lubricating composition ranges from 2.4 mPa.s −1  to 5 mPa.s −1 . 
     
     
         7 . The method according to  claim 1 , wherein the lubricating composition has a grade according to SAEJ300 classification of type XW-(Y) where X represents 0, 5 or 10 and Y represents an integer from 6 to 50. 
     
     
         8 . The method according to  claim 1 , wherein the quantity of base oil of mixture of base oils used is comprised between 50% to 97% by weight with respect to the total weight of the lubricating composition. 
     
     
         9 . The method according to  claim 1 , wherein the lubricating composition further comprises at least one additive improving the viscosity index, chosen from the group consisting of hydrogenated butylene and styrene polymers, ethylene propylene copolymers and polymethacrylate polymers. 
     
     
         10 . The method according to  claim 1 , wherein the reduction of particle emissions relates to the cycle WLTC and/or the cycle RDE. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . A method of reducing particulate emission in a controlled ignition internal combustion engine, comprising the use of a lubricating composition comprising a base oil or a mixture of base oils, wherein said base oil or mixture of base oils has a kinematic viscosity (BOV or base oil viscosity) measured at 100° C., as per the standard ASTM D445, of less than or equal to 4.5 mm 2 /s, and wherein said lubricating composition has a viscosity at 150° C. and under constant shear, greater of equal to 2.4 mPa.s −1 . 
     
     
         16 . The method according to  claim 15 , wherein the lubricating composition has a viscosity at 150° C., and under constant shear, ranging from 2.4 mPa.s −1  to 5 mPa.s −1  and/or wherein the lubricating composition has a grade according to SAEJ300 classification of type XW-(Y) where X represents 0, 5 or 10 and Y represents an integer from 6 to 50. 
     
     
         17 . The method according to  claim 15 , wherein the viscosity index of the base oil or of the mixture of base oils is greater than or equal to 130. 
     
     
         18 . The method according to  claim 15 , wherein the kinematic viscosity, measured at 100° C., of the base oil or of the mixture of base oils is comprised between 1.5 and 4.5 mm 2 /s. 
     
     
         19 . The method according to  claim 15 , wherein the quantity of base oil of mixture of base oils used is comprised between 50% to 97% by weight with respect to the total weight of the lubricating composition.