[Problem]

From the points of view of improving the fuel efficiency of automobiles and industrial machines and saving energies thereof, the present invention provides lubricants having outstanding shear stability and low-temperature viscosity characteristics.

[Solution]

A lubricant composition includes a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 10 mm.sup.2/s, and an ethylene/α-olefin copolymer (B) in which (B1) the peak top molecular weight is 3,000 to 10,000, (B2) the copolymer shows no melting peak, (B3) the value B is not less than 1.1 and (B4) the kinematic viscosity at 100° C. is 140 to 500 mm.sup.2/s. The lubricant composition has a kinematic viscosity at 100° C. of not more than 20 mm.sup.2/s, a peak top of molecular weight in the range of 3,000 to 10,000, and a weight fraction of components having a molecular weight not less than 20,000 of 1 to 10% relative to all components having a molecular weight not less than the molecular weight that gives the peak top.

[Problem]

From the points of view of improving the fuel efficiency of automobiles and industrial machines and saving energies thereof, the present invention provides lubricants having outstanding shear stability and low-temperature viscosity characteristics.

[Solution]

A lubricant composition includes a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 10 mm.sup.2/s, and an ethylene/α-olefin copolymer (B) in which (B1) the peak top molecular weight is 3,000 to 10,000, (B2) the copolymer shows no melting peak, (B3) the value B is not less than 1.1 and (B4) the kinematic viscosity at 100° C. is 140 to 500 mm.sup.2/s. The lubricant composition has a kinematic viscosity at 100° C. of not more than 20 mm.sup.2/s, a peak top of molecular weight in the range of 3,000 to 10,000, and a weight fraction of components having a molecular weight not less than 20,000 of 1 to 10% relative to all components having a molecular weight not less than the molecular weight that gives the peak top.

A lubricating grease composition, and more specifically, to a lubricating grease composition which, when used with an article clamping device, such as a chuck, produces excellent lubricating properties whilst remaining strongly adhered to metal parts in the clamping mechanism of the device and showing enhanced chemical and physical resistance to fluids such as cutting fluids with which they come into contact.

A lubricating grease composition, and more specifically, to a lubricating grease composition which, when used with an article clamping device, such as a chuck, produces excellent lubricating properties whilst remaining strongly adhered to metal parts in the clamping mechanism of the device and showing enhanced chemical and physical resistance to fluids such as cutting fluids with which they come into contact.

A lubricating oil composition, and a method of reducing LSPI events employing the lubricating oil composition, including a base oil of lubricating viscosity, and an additive composition including: one or more overbased calcium-containing detergent(s) sufficient to provide at least 500 ppmw of calcium, and a zirconium-containing nanoparticle(s) and/or one or more zirconium-containing compound(s) sufficient to provide greater than 0 ppmw to 6000 ppmw of zirconium, wherein the nanoparticles have a size of from 1 to 500 nm, as measured by Dynamic Light Scattering, an amount of one or more molybdenum-containing compound present in an amount sufficient to provide no greater than 100 ppmw of molybdenum, and wherein the additive composition has a weight ratio of ppmw of zirconium provided by the zirconium-containing nanoparticle(s) and/or the one or more zirconium-containing compound(s) to the ppmw of calcium provided by the one or more overbased-calcium-containing detergent(s) of greater than about 0.01 to less than 5.

A lubricating oil composition, and a method of reducing LSPI events employing the lubricating oil composition, including a base oil of lubricating viscosity, and an additive composition including: one or more overbased calcium-containing detergent(s) sufficient to provide at least 500 ppmw of calcium, and a zirconium-containing nanoparticle(s) and/or one or more zirconium-containing compound(s) sufficient to provide greater than 0 ppmw to 6000 ppmw of zirconium, wherein the nanoparticles have a size of from 1 to 500 nm, as measured by Dynamic Light Scattering, an amount of one or more molybdenum-containing compound present in an amount sufficient to provide no greater than 100 ppmw of molybdenum, and wherein the additive composition has a weight ratio of ppmw of zirconium provided by the zirconium-containing nanoparticle(s) and/or the one or more zirconium-containing compound(s) to the ppmw of calcium provided by the one or more overbased-calcium-containing detergent(s) of greater than about 0.01 to less than 5.

A sliding material composition comprising a polymer component comprising (A) a high-density polyethylene and (B) an olefin block copolymer; and (C) a silane coupling agent; wherein the Si content is 0.1 to 15% by mass based on the mass of the entire sliding material composition. The sliding material composition has the same level of slidability as a resin to which particles are added.

A lubricating oil composition for industrial gears, including 10 to 90% by mass of a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 100 mm.sup.2/s, a viscosity index of 100 or more, and a pour point of 0° C. or lower, and 90 to 10% by mass of a liquid random copolymer (B) of ethylene and α-olefin, the liquid random copolymer (B) being prepared by means of a specific catalyst, wherein the total amount of (A) and (B) is 100% by mass, the lubricating oil composition for industrial gears having a kinematic viscosity at 40° C. of 100 to 10,000 mm.sup.2/s.

A lubricating oil composition for industrial gears, including 10 to 90% by mass of a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 100 mm.sup.2/s, a viscosity index of 100 or more, and a pour point of 0° C. or lower, and 90 to 10% by mass of a liquid random copolymer (B) of ethylene and α-olefin, the liquid random copolymer (B) being prepared by means of a specific catalyst, wherein the total amount of (A) and (B) is 100% by mass, the lubricating oil composition for industrial gears having a kinematic viscosity at 40° C. of 100 to 10,000 mm.sup.2/s.

A grease composition including 10 to 98% by mass of a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 14 mm.sup.2/s, a viscosity index of 100 or more, and a pour point of 0° C. or lower, 89 to 1% by mass of a liquid random copolymer (B) of ethylene and α-olefin produced by using a specific catalyst, and 1 to 30% by mass of a thickener (C) (note that the sum total of (A) to (C) is 100% by mass), wherein the lubricant base oil (A) and the copolymer (B) are mixed in such a ratio that the mixture of the lubricant base oil (A) and the ethylene-α-olefin copolymer (B) has a kinematic viscosity at 100° C. of 1 to 500 mm.sup.2/s and a viscosity index of 120 or more.