A lubricating grease composition for a resin member is used to be supplied as a lubricant on a surface of at least a sliding portion of a resin member including the sliding portion with an other member. The lubricating grease composition for a resin member contains a base oil which is a mixed oil of a poly--olefin having a kinetic viscosity at 40 C. of 18 to 50 mm.sup.2/s and an ethylene--olefin copolymer having a number average molecular weight of 40,000 to 200,000, a lithium-based complex soap as a thickener and a polytetrafluoroethylene resin as a solid lubricant having a mixing ratio of 4 to 12 mass % to the entire lubricating grease composition, wherein the base oil has a kinetic viscosity at 40 C. of 80 to 200 mm.sup.2/s and a worked penetration of the lubricating grease composition ranges from 265 to 340.

Disclosed is food-grade lubricating grease and a method for preparing the same, belonging to the technical field of lubricating grease. The food-grade lubricating grease is prepared from the following components in percentage by mass: 75% to 85% of food-grade white oil, 6% to 16% of stearic acid, 2.0% to 3.0% of benzoic acid, 4.7% to 8.7% of aluminum isopropoxide, 1.0% to 1.5% of water and 1.0% to 7.0% of nano-PTFE, and has good extreme-pressure, abrasion-resistant and friction-reduction properties, a last non-seizure load (P.sub.B) reaching 411.6 N, a sintering load (P.sub.D) reaching 1,960 N, and a friction coefficient reduced by 18.5%. The lubricating grease can be used for a food production industry and in household food appliances, the service life of a device and the service life of the food-grade lubricating grease are effectively prolonged, and meanwhile, food security is guaranteed to a certain degree.

Provided is a mixed grease containing a grease (A) prepared from a base oil (a1) and a thickening agent (a2) that is a lithium soap consisting of a lithium salt of a monovalent fatty acid, and a grease (B) prepared from a base oil (b1) and a thickening agent (b2) that is a lithium complex soap consisting of a lithium salt of a monovalent fatty acid and a lithium salt of a divalent fatty acid. The mixed grease has good wear resistance and load bearing properties and has excellent grease leakage preventing properties.

An overbased sulfonate modified lithium carboxylate grease composition and method of manufacture comprising overbased calcium sulfonate, overbased magnesium sulfonate, or both added to a source of lithium hydroxide, base oil, and optionally one or more acids when a complex grease is desired. When overbased sulfonate is added, the amount of dicarboxylic acid relative monocarboxylic acid may be reduced. Additionally, the amount of lithium hydroxide added may be less than stoichiometrically needed to react with the acids. A sulfonate modified lithium grease with improved thickener yield and dropping point may be made without multiple heating and cooling cycles or using a pressurized kettle.

Provided is a particle-containing grease composition that can efficiently improve friction and wear resistance properties with a small added amount and exhibits excellent friction and wear resistance properties even when a clearance and the surface roughness of the friction surface in sliding parts are extremely small. The particle-containing grease composition includes base oil, a thickener, and molybdenum disulfide particles, in which a median diameter D.sub.50 of the molybdenum disulfide particles determined by a dynamic light scattering method is 10 nm or more and less than 450 nm.

Provided is a particle-containing grease composition that can efficiently improve friction and wear resistance properties with a small added amount and exhibits excellent friction and wear resistance properties even when a clearance and the surface roughness of the friction surface in sliding parts are extremely small. The particle-containing grease composition includes base oil, a thickener, and molybdenum disulfide particles, in which a median diameter D.sub.50 of the molybdenum disulfide particles determined by a dynamic light scattering method is 10 nm or more and less than 450 nm.

A lubricating grease composition includes a base oil, a thickener, and a solid lubricant, wherein the base oil is a synthetic hydrocarbon oil with a kinematic viscosity of 600 to 2000 mm.sup.2/s at 40 C., the thickener is a barium complex soap, and the solid lubricant is an inorganic fine particle with Mohs hardness of 3 to 6 and an average particle size of 10 to 40 m.

A lubricating grease composition includes a base oil, a thickener, and a solid lubricant, wherein the base oil is a synthetic hydrocarbon oil with a kinematic viscosity of 600 to 2000 mm.sup.2/s at 40 C., the thickener is a barium complex soap, and the solid lubricant is an inorganic fine particle with Mohs hardness of 3 to 6 and an average particle size of 10 to 40 m.

A robot includes a first member, a second member provided to be capable of turning with respect to the first member, and a gear device configured to transmit a driving force from one side to the other side of the first member and the second member. The gear device includes an internal gear, an external gear having flexibility and configured to partially mesh with the internal gear, a wave generator configured to be in contact with the external gear and move a meshing position of the internal gear and the external gear in a circumferential direction, and lubricant disposed in at least one of a meshing section of the internal gear and the external gear and a portion where the external gear and the wave generator are in contact with each other. A last non-seizure load of the lubricant is 300 N or more.

A robot includes a first member, a second member provided to be capable of turning with respect to the first member, and a gear device configured to transmit a driving force from one side to the other side of the first member and the second member. The gear device includes an internal gear, an external gear having flexibility and configured to partially mesh with the internal gear, a wave generator configured to be in contact with the external gear and move a meshing position of the internal gear and the external gear in a circumferential direction, and lubricant disposed in at least one of a meshing section of the internal gear and the external gear and a portion where the external gear and the wave generator are in contact with each other. A last non-seizure load of the lubricant is 300 N or more.