Provided is a lubricating grease used for lubricating mechanical elements having a reciprocating sliding ball interposed therebetween and maintaining flaking resistance even under a high load in mechanical elements having a reciprocating sliding ball interposed therebetween. The present invention therefore provides a grease composition comprising a base oil (a), a diurea compound (b), an amide compound (c), and a thiophosphorous compound or a thiophosphoric acid ester compound (d), wherein the diurea compound (b) includes a compound represented by Formula (1) R.sub.1—NHCONH—R.sub.2—NHCONH—R.sub.3 (1) wherein R.sub.1 and R.sub.3 represent an acyclic aliphatic hydrocarbon group having from 8 to 20 carbon atoms, and R.sub.2 represents a diphenylmethane group.

Provided is a lubricating grease used for lubricating mechanical elements having a reciprocating sliding ball interposed therebetween and maintaining flaking resistance even under a high load in mechanical elements having a reciprocating sliding ball interposed therebetween. The present invention therefore provides a grease composition comprising a base oil (a), a diurea compound (b), an amide compound (c), and a thiophosphorous compound or a thiophosphoric acid ester compound (d), wherein the diurea compound (b) includes a compound represented by Formula (1) R.sub.1—NHCONH—R.sub.2—NHCONH—R.sub.3 (1) wherein R.sub.1 and R.sub.3 represent an acyclic aliphatic hydrocarbon group having from 8 to 20 carbon atoms, and R.sub.2 represents a diphenylmethane group.

The invention relates to lubricating greases based on alkali metal soaps and/or earth-alkali metal soaps and metal complex soaps based on (R)-10-hydroxyoctadecanoic acid and to the use thereof.

The invention relates to lubricating greases based on alkali metal soaps and/or earth-alkali metal soaps and metal complex soaps based on (R)-10-hydroxyoctadecanoic acid and to the use thereof.

Provided is a grease composition for a ball joint that can reduce the wear of a ball seat at a slide region and also has excellent compatibility with a dust cover. The grease composition for a ball joint comprises a base oil, a thickener, and an additive. The base oil contains an ethylene-α-olefin copolymer and the kinetic viscosity of the base oil at 40° C. is 2,000 to 6,000 mm.sup.2/s. The additive contains a polar wax (e.g., monoamide wax or ester wax).

An object of the present invention is to provide a grease composition which has little influence on the environment and has good rust prevention and water resistance against salt water such as sea water. The grease composition comprises a biodegradable base oil and a rust-preventive agent comprising a calcium sulfonate complex and a sorbitan fatty acid ester, wherein a total content of biodegradable organic substances in the grease composition is 75% by mass or more, and wherein a content of the rust-preventive agent is 2.5 to 30% by mass.

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, and a calcium soap of fatty acid having 12 to 24 carbon atoms. 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 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, and a calcium soap of fatty acid having 12 to 24 carbon atoms. 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 invention provides a lubricant composition comprising: (i) a base oil (ii) an organophilic clay-based thickener; and (iii) a solid lubricant, wherein said solid lubricant does not comprise any heavy metals. The present invention also provides the use of a lubricant composition comprising: a base oil; an organophilic clay-based thickener; and a solid lubricant, wherein said solid lubricant does not comprise any heavy metals, as a pipe dope.

The present invention provides a lubricant composition comprising: (i) a base oil (ii) an organophilic clay-based thickener; and (iii) a solid lubricant, wherein said solid lubricant does not comprise any heavy metals. The present invention also provides the use of a lubricant composition comprising: a base oil; an organophilic clay-based thickener; and a solid lubricant, wherein said solid lubricant does not comprise any heavy metals, as a pipe dope.