A sliding mechanism includes first and second members slidable relative to each other and a grease composition interposed between the first and second members and containing a thickening agent and a base oil, wherein the grease composition contains lithium 12-hydroxystearate as the thickening agent and dioctyl sebacate and/or poly--olefin as the base oil; and wherein at least one of the first and second member has a sliding surface coated with a hard carbon film of diamond-like carbon.

A sliding mechanism includes first and second members slidable relative to each other and a grease composition interposed between the first and second members and containing a thickening agent and a base oil, wherein the grease composition contains lithium 12-hydroxystearate as the thickening agent and dioctyl sebacate and/or poly--olefin as the base oil; and wherein at least one of the first and second member has a sliding surface coated with a hard carbon film of diamond-like carbon.

The invention provides a lubricant composition for an eccentrically oscillating speed reducer of planetary gear type, which is capable of extending the life of the speed. reducer under high temperatures and keeping low input torque at low temperatures, and includes (a) a base oil containing a synthetic oil, (b) a hydrocarbon wax, and (c) at least one calcium salt selected from the group consisting of a calcium salt of petroleum sulfonic acid, a calcium salt of alkyl aromatic sulfonic acid, a calcium salt of oxidized wax, an overbasic calcium salt of petroleum sulfonic acid, an overbasic calcium salt of alkyl aromatic sulfonic acid, and an overbasic calcium salt of oxidized wax.

A grease composition containing base oil, a thickener, and an additive, wherein said additive contains at least one kind selected from among a phosphite ester shown by a chemical formula (1) or a phosphite ester shown by a chemical formula (2); a content of said phosphite ester is 0.5 to 4 parts by weight for 100 parts by weight which is a total of an amount of said base oil and that of said thickener; and said additive contains neither phosphite esters other than said phosphite ester shown by said formula (1) or by said formula (2) nor phosphate esters having organic groups whose carbon number is not less than three:

##STR00001##

A grease composition containing base oil, a thickener, and an additive, wherein said additive contains at least one kind selected from among a phosphite ester shown by a chemical formula (1) or a phosphite ester shown by a chemical formula (2); a content of said phosphite ester is 0.5 to 4 parts by weight for 100 parts by weight which is a total of an amount of said base oil and that of said thickener; and said additive contains neither phosphite esters other than said phosphite ester shown by said formula (1) or by said formula (2) nor phosphate esters having organic groups whose carbon number is not less than three:

##STR00001##

The present application relates to polyurea/calcium sulfonate complex grease composition for use in constant velocity joints. The invention discloses a lubricating grease with thixotropy and a preparation method thereof. The lubricating grease comprises a polyurea/high base number calcium sulfonate composite thickener, colloidally dispersed calcium carbonate solid particles in the form of calcite, a calcium borate or calcium borate composite, a calcium soap of fatty acid having 12 to 24 carbon atoms, an organic molybdenum compound, and an antioxidant. The above components are uniformly dispersed in an oil phase medium. The content of high base number calcium sulfonate in the lubricating grease is less than 22 wt %.

The present application relates to polyurea/calcium sulfonate complex grease composition for use in constant velocity joints. The invention discloses a lubricating grease with thixotropy and a preparation method thereof. The lubricating grease comprises a polyurea/high base number calcium sulfonate composite thickener, colloidally dispersed calcium carbonate solid particles in the form of calcite, a calcium borate or calcium borate composite, a calcium soap of fatty acid having 12 to 24 carbon atoms, an organic molybdenum compound, and an antioxidant. The above components are uniformly dispersed in an oil phase medium. The content of high base number calcium sulfonate in the lubricating grease is less than 22 wt %.

Additive packages including multifunctional additive molecules are disclosed, including, for example, organic medium intercalated with lubricant nanoparticles. The additive package may be greaseless or may be added to materials such as base oils or greases, greaseless materials, or anti-corrosives, for example. The additive package added to materials may form a coating or lubricant that may be added to a surface of an object.

Provided herein are grease compositions comprising at least one estolide compound of formula: ##STR00001##
in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 2; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided are methods of making estolide-based grease products.

Provided herein are grease compositions comprising at least one estolide compound of formula: ##STR00001##
in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 2; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided are methods of making estolide-based grease products.