The present invention relates to the use, for cooling and lubricating a propulsion system of an electric or hybrid vehicle, of a composition comprising: (i) at least one base oil; and (ii) at least one diester of formula R.sup.a—C(O)—O—([C((R).sub.2)].sub.n—O).sub.s—C(O)—R.sup.b (I), different than the base oil (i). The invention also relates to a method of cooling and lubricating a propulsion system of an electric or hybrid vehicle comprising at least one step of bringing at least one mechanical component of said system into contact with a composition as defined above.

The present invention relates to the use, for cooling and lubricating a propulsion system of an electric or hybrid vehicle, of a composition comprising: (i) at least one base oil; and (ii) at least one diester of formula R.sup.a—C(O)—O—([C((R).sub.2)].sub.n—O).sub.s—C(O)—R.sup.b (I), different than the base oil (i). The invention also relates to a method of cooling and lubricating a propulsion system of an electric or hybrid vehicle comprising at least one step of bringing at least one mechanical component of said system into contact with a composition as defined above.

The invention relates to a method for preparing a composition of diesters comprising reacting an unsaturated compound of alcohol type or the ester thereof, with a saturated fatty acid, in the presence of an acid catalyst. The invention also relates to a composition of diesters that is obtainable by the method of the invention, and the use thereof in lubricating compositions or in cosmetic or pharmaceutical compositions.

The present invention relates to a method of inhibiting corrosion experienced during use of a base oil or lubricant by the addition of a polyester corrosion inhibitor. More especially, the polyester corrosion inhibitor is the reaction product of an alk(en)yl substituted succinic anhydride wherein the average number of succinic groups per alk(en)yl group is less than 3.0, and at least one polyol. There is also provided a composition comprising such a polyester corrosion inhibitor and use of such a composition as a corrosion inhibitor, as well as a base oil or lubricant comprising such a polyester corrosion inhibitor.

Provided are a lubricant composition for shock absorbers, a lubricant additive, and a method of adjusting friction characteristics of a lubricant composition for shock absorbers, each capable of satisfying both the operational stability and ride comfort. The lubricant composition for shock absorbers contains a base oil and a friction adjusting agent, the friction adjusting agent contains pentaerythritol esters, and the pentaerythritol esters contain a pentaerythritol tetraester and a pentaerythritol ester other than the pentaerythritol tetraester.

Provided are a lubricant composition for shock absorbers, a lubricant additive, and a method of adjusting friction characteristics of a lubricant composition for shock absorbers, each capable of satisfying both the operational stability and ride comfort. The lubricant composition for shock absorbers contains a base oil and a friction adjusting agent, the friction adjusting agent contains pentaerythritol esters, and the pentaerythritol esters contain a pentaerythritol tetraester and a pentaerythritol ester other than the pentaerythritol tetraester.

Provided is an engine oil lubricant composition with improved fuel efficiency. The engine oil lubricant composition may include: a polyalpha olefin base oil component an amount of about 50 wt % to about 90 wt % based on a total weight of the engine oil lubricant composition, wherein the polyalpha olefin base oil component is a Group IV base oil and has a Noack volatility of about 12.5% to about 15%; a Group II base oil component in an amount of about 0.1 wt % to about 50 wt % based on the total weight of the engine oil lubricant composition. The engine oil lubricant composition may have (i) a kinematic viscosity at 100° C. of about 10 cSt or less, (ii) a high temperature high shear viscosity at 150° C. of about 2.2 cP or less, and (iii) a Noack volatility of about 20% or less.

Provided is an engine oil lubricant composition with improved fuel efficiency. The engine oil lubricant composition may include: a polyalpha olefin base oil component an amount of about 50 wt % to about 90 wt % based on a total weight of the engine oil lubricant composition, wherein the polyalpha olefin base oil component is a Group IV base oil and has a Noack volatility of about 12.5% to about 15%; a Group II base oil component in an amount of about 0.1 wt % to about 50 wt % based on the total weight of the engine oil lubricant composition. The engine oil lubricant composition may have (i) a kinematic viscosity at 100° C. of about 10 cSt or less, (ii) a high temperature high shear viscosity at 150° C. of about 2.2 cP or less, and (iii) a Noack volatility of about 20% or less.

This ball screw grease composition for a rack-assisted electric power steering contains a thickener, a base oil, and at least one compound selected from the group consisting of a Ca sulfonates, fatty acids, and triglycerides, wherein the kinematic viscosity of the base oil at 40° C. is 4-100 mm2/s, and the worked penetration of the composition is 265-385.

This ball screw grease composition for a rack-assisted electric power steering contains a thickener, a base oil, and at least one compound selected from the group consisting of a Ca sulfonates, fatty acids, and triglycerides, wherein the kinematic viscosity of the base oil at 40° C. is 4-100 mm2/s, and the worked penetration of the composition is 265-385.