Lubricating compositions are disclosed which comprise a major amount of an oil of lubricating viscosity, thickened to a grease consistency with an oil thickener and a minor amount of a rare earth halide.
Novel lubricant compositions contain at least one rare earth halide, e.g., cerium trifluoride, and at least one surfactant including a hydrophobic moiety and a hydrophilic moiety, such hydrophilic moiety comprising ethylene oxide and/or propylene oxide units and, optionally, hydrophilic functional groups, dispersed in an oily medium compatible therewith.
Novel aqueous lubricant dispersions contain at least one rare earth halide, e.g., cerium trifluoride, and at least one polymeric dispersing agent therefor, such at least one dispersing agent including: (a) a copolymer of an ethylenically unsaturated carboxylic acid or derivative thereof with an .alpha.-olefin comonomer and/or a vinyl comonomer; (b) a homopolymer or copolymer of an ethylenically unsaturated carboxylic acid or derivative thereof; (c) a copolymer of at least one ethylenically unsaturated carboxylic acid and at least one ethylenically unsaturated sulfonic acid comonomer; and/or (d) a polymer of an alkylene oxide of an (arylalkyl)phenol, or phosphated or sulfated derivative thereof.
Additives comprising a salt or complex of tetrathiocarbonic acid are useful in lubricants to enhance both the extreme pressure/anti-wear and anti-oxidant capabilities thereof. The lubricants preferably are oils of lubricating viscosity, which may be thickened to grease-like consistency with one or more oil thickeners, and contain from about 0.1 to about 20 weight percent of said additives.
A data storage device of the type having a rotating member mounted on a shaft, said data storage device comprising a lubricant provided between the shaft and the rotating member, wherein the lubricant comprises (a) a linear, nonpolar polyether base oil having a glass transition temperature (T.sub.g) of about -110.degree. C. or less and an activation energy of flow (E.sub.a) of about 30 kJ/mol or less, and (b) an amount of a thickening agent sufficient to provide the lubricant with a grease-like consistency.
A process for upgrading technical low grade cerium/fluorine-containing residues having concentrations of silicon and iron above about 1.0 weight percent produces compositions wherein the combined silicon and iron content is less than about 1.0 weight percent. Typically, the cerium content is raised to above about 50 weight percent and sufficient fluorine is present for the fluorine-to-cerium molar ratio to be 3.0 or above. Lubricating compositions comprising a major part of a lubricant and a minor amount of said upgraded cerium/fluorine-containing residue are useful as anti-wear lubricants.
