A dispersant for a lubricating oil, containing at least one compound selected from a specific nitrogen-containing compound which is obtained by using, as raw materials, (A) at least one polyolefin selected from polybutene and polyisobutene, (B) at least one maleic acid compound selected from maleic acid and maleic anhydride, and (C) polyamine; a boride of the specific nitrogen-containing compound; and an acylated product of the specific nitrogen-containing compound. The polyolefin (A) satisfies at least one of the following conditions () and (). () a ratio (Sb/Sa) of an integrated value (Sb) of a peak present at 4.40 to 5.00 ppm in a .sup.1H-NMR spectrum to an integrated value (Sa) of a peak present at 5.01 to 5.60 ppm in the 1H-NMR spectrum is 2 or more. () a ratio (Sd/Sc) of an integrated value (Sd) of a peak present at 1.76 to 2.10 ppm in the 1H-NMR spectrum to an integrated value (Sc) of a peak present at 1.65 to 1.75 ppm in the .sup.1H-NMR spectrum is 1 or more.

A lubricating composition suited for use in lubricating a driveline device includes an oil of lubricating viscosity and a compound comprising a polyolefin-substituted bridged hydroxyaromatic compound or metal salt thereof, wherein the polyolefin is derived from a isobutylene having a number average molecular weight of 150 to 800.

A polyisobutylene-substituted hydroxyaromatic compound and derivatives thereof which are suitable for use as additives in lubricating compositions. The polyisobutylene-substituted hydroxyaromatic compound may include the reaction product of a hydroxyaromatic compound with a polyisobutylene having a number average molecular weight of 150 to 800.

The disclosed technology provides a lubricating composition comprising an oil of lubricating viscosity and a detergent comprising a polyolefin-substituted hydroxy-aromatic carboxylic acid or salt thereof, wherein the polyolefin is derived from a branched alkene having at least 4 carbon atoms and wherein the polyolefin has a number average molecular weight of 150 to 800. The invention further relates to a method of lubricating a mechanical device with the lubricant composition.

Disclosed is a lubricant for use in cold forming of a metal. The lubricant comprises a mixture of at least one lubricating compound and at least one starch. The starch adheres the lubricating compound to the metal surface. The present lubricant completely removes the need to pre-coat the metal with a zinc phosphate coating to adhere the lubricating compound to the metal. The present lubricant eliminates several steps required in processes that utilize zinc phosphate pre-coatings. In addition, the lubricant of the present invention is easily removed after the cold forming operations unlike zinc phosphate coatings.

Provided is a grease composition containing a base oil, a thickener, and an additive. The base oil contains a poly--olefin and has a kinematic viscosity of 20-60 mm.sup.2/s at 40 C. The thickener contains a urea compound produced by reacting a diisocyanate compound with a mixed amine containing an alicyclic amine and an aromatic amine. The additive contains a phosphorous acid ester, an ether compound, and an oxidized paraffin.

The disclosure includes a grease composition comprising providing at least one polyol-ester base oil, at least one fatty-acid metal soap, at least one dimercaptothiadiazole derivative, and at least one sulfurous fatty-acid ester, the amount of active sulfur provided by the sulfurous fatty-acid ester at 150 C. according to the ASTM D1662 standard being greater than or equal to 0.18 wt % with respect to the total weight of the grease composition.

A solid lubricant containing a fatty acid metal salt and a polyethylene having an acid value is prepared. The solid lubricant is disposed so as to be applied on a surface of an image bearing member of an image forming apparatus in electrophotography, and a lubricant layer is formed on the surface of the image bearing member with the solid lubricant.

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 solid lubricant containing a fatty acid metal salt and a polyethylene having an acid value is prepared. The solid lubricant is disposed so as to be applied on a surface of an image bearing member of an image forming apparatus in electrophotography, and a lubricant layer is formed on the surface of the image bearing member with the solid lubricant.