Abstract: A grease composition, which comprises (A) a perfluoropolyether base oil, (B) a thickener, and (C) barium sulfate and/or antimony oxide, where 0.1-50% by weight of the component (B) and 1-25% by weight of the component (C) are contained, has a distinguished effect on improvements of abrasion resistance, friction characteristics, load durability, high-temperature durability and corrosion resistance without any deterioration of heat resistance by adding at least one of barium sulfate and antimony oxide, each having an average primary particle size of 0.1-20 ?m, as component (C).

Abstract: Use as additive to stabilize perfluoropolyether lubricant oils at high temperatures, preferably higher than 200° C., of a solid polymer at room temperature, having a softening or a melting point higher than 150° C., preferably higher than 200° C., and containing in the repeating unit at least one aromatic ring; preferably in the backbone, and lubricating compositions containing said additive.

Abstract: Disclosed herein are azeotrope compositions comprising 1,2,3,3,3-pentafluoropropene and hydrogen fluoride. The azeotrope compositions are useful in processes to produce and in processes to purify 1,2,3,3,3-pentafluoropropene. Additionally, disclosed herein are azeotrope and near-azeotrope compositions comprising 1,1,1,2,3,4,4,5,5,5-decafluoropentane and hydrogen fluoride.

Abstract: The invention provides for a process and apparatus for preparing a soap concentrate, including: (a) introducing feed components to a first feeding zone; (b) first reacting in a first reacting zone; (c) first venting in a first venting zone; and (d) cooling in a cooling zone. The process may further include, after (c) and before (d): (i) continued reacting in a continued reacting zone; and (ii) second venting in a second venting zone. The invention also provides for a process and apparatus for preparing a lubricating composition comprising: (aa) introducing a soap concentrate and a base oil to a lubricating composition feeding zone; (bb) dispersing the soap concentrate in a lubricating composition dispersing zone; (cc) mixing the soap concentrate and the base oil in a lubricating composition mixing zone; and (dd) cooling in a lubricating composition cooling zone.

Abstract: The invention relates to thermally conductive greases that may contain carrier oil(s), dispersant(s), and thermally conductive particles, wherein the thermally conductive particles are a mixture of at least three distributions of thermally conductive particles, each of the at least three distributions of thermally conductive particles having an average (D50) particle size which differs from the other average particle sizes by at least a factor of five. The thermally conductive greases of the invention exhibit desirable rheological behavior during installation/application and during use of devices involving these materials.

Abstract: An electric submersible motor is provided that includes a plurality of rotors and bearings mounted on a shaft, and a stator external to said rotors. A running clearance is located between an inner diameter of the stator and external diameter of the rotors, and includes a lubricating oil that includes a base hydrocarbon oil and a plurality of nanoparticles. Also provided is an improved lubricant oil and method of preparation thereof are provided. The lubricant oil includes a hydrocarbon containing base oil and a plurality of nanoparticles. The nanoparticles may be present in an amount up to 30% by volume.

Abstract: The production of solid lubricant agglomerates by combining solid lubricant powder, an inorganic binder, other fillers if optionally desired, and a liquid to form a mixture, and driving off the liquid to form dry agglomerates which are subsequently classified by size or milled and classified by size to yield agglomerates of a desired size range. These agglomerates are then treated to stabilize the binder, thereby strengthening the binder and rendering it nondispersible in the liquid. The treated agglomerates are then blended or clad with a metal, metal alloy or a metallic composition, to produce a composition suitable for thermal spray applications.

Abstract: The hot stretch forming of sheet metal alloys, such as highly deformable aluminum alloy materials, is improved by using a lubricant comprising bismuth between the forming tool and the engaged surface of the sheet metal. A precursor of bismuth, such as bismuth subsalicylate, may be dispersed in a liquid and applied to the sheet metal before the sheet is heated to its forming temperature. Other lubricants such as boron nitride may be combined with the bismuth precursor. The precursor compound is decomposed to bismuth (or bismuth and carbon in the case of bismuth subsalicylate) which lubricates contact between the surface(s) of the sheet and the forming tool during forming and removal of the formed part from the tool.

Abstract: Novel hydrated-lime slurry compositions are disclosed, which include a heat-stable polymeric dispersant. The polymeric dispersant is capable to withstand temperatures in excess of 212° F. experienced by the slurry as a result of the hydrolysis of quicklime to produce hydrated lime, and accordingly can be added to the slurry composition prior to the addition of quicklime. Methods for making such slurry compositions are also disclosed.

Abstract: Disclosed herein is a lubricant composition comprising soybean oil; and molybdenum disulfide; the molybdenum disulfide being dispersed in the soybean oil. Disclosed herein too is a method comprising agitating molybdenum disulfide with soybean oil in a reactor; the mixing being conducted in the presence of a magnetic field that is greater than the earth's field and an electrical field. Disclosed herein too is a coolant composition comprising water; soap and/or a surfactant; and a lubricant composition; the lubricant composition comprising soybean oil and molybdenum disulfide. Disclosed herein too is a method of manufacturing a coolant composition comprising mixing a lubricant composition, water and soap; the lubricant composition comprising a base oil and a metal sulfide.

Abstract: A lubricant for use in processing of a metallic material includes a lubricant base composed of at least one paraffinic hydrocarbon and a modifier oil added to the lubricant base at a rate of 2-20 wt % of total weight of the lubricant. The modifier oil contains (a) a sulfuric extreme pressure agent, (b) a rust inhibitive agent and (c) a calcium ingredient. Content of sulfur is 0.5-20 wt % of total weight of the modifier oil. Content of the rust inhibitive agent is 0.1-15 wt % of total weight of the modifier oil. Further, content of calcium is 0.1-15 wt % of total weight of the modifier oil.

Abstract: Embodiments of the invention include compositions of calcium/lithium complex greases containing calcium/lithium soaps having a high calcium fraction and complexing agents, encapsulated constant velocity shafts containing such lubricating greases and the use of the lubricating greases in encapsulated shafts of constant velocity shafts.

Abstract: The present invention aims to improve the extreme-pressure properties and compatibility with seals of lubricating grease compositions used at lubrication points where extreme-pressure properties and seal-resistance properties at high loads are required in various kinds of machinery. To this end the present invention provides a lubricating grease composition wherein from 0.1 to 3% by weight of a molybdenum dialkyl dithiocarbamate, from 0.1 to 3% by weight of benzothiazole compounds and from 0.1 to 3% by weight of calcium sulphonates are incorporated in a grease in which a thickening agent is blended in the base oil.

Abstract: To form a coating film having an excellent wear-resistant property in a temperature range from low temperature to high temperature a coating-film forming method includes a metal-powder producing step of producing a metal powder containing an element exhibiting a lubricating property when oxidized; an oxidizing step of oxidizing the metal powder so that an amount of oxygen contained in the metal powder is within 6 weight % to 14 weight %; and a coating-film forming step of forming a coating film on a material subject to a treatment, the coating film having such a composition that an area where an oxygen content is 3 weight % or less and an area where an oxygen content is 8 weight % or more are distributed in a unit area of the coating film when the metal powder is in a melted state or a semi-melted state, and an oxygen content of the entire coating film after the metal powder is melted or semi-melted being within 5 weight % to 9 weight %.

Abstract: The present invention relates to additives for use in lubricant compositions to processes for producing the additives, and to the use of the additives in lubricants and in systems that are lubricated. More specifically, the additive includes a capped particle comprising: (i) one or more core particles wherein the core particle is an inorganic particle having a dimension less than about 5 ?m; and (ii) one or more multi-block copolymers attached to the inorganic particles, wherein the multi-block copolymer comprises a) at least one nonpolar polymer block; b) at least one first polar polymer block; and c) at least one second polar polymer block; wherein the nonpolar polymer block is interposed between the first polar polymer block and the second polar polymer block, the first polar polymer block is attached to the core particle, and at least a portion of the second polar polymer block is not attached to the core particle.

Abstract: The present invention provides a surface-oxide abrasion-resistant lubricant coating that can maintain high lubricity for a long time without wear of a base material and a coating or damage to an object to be contacted by a simpler method and with less expensive material. A mixed fluid of a compressed gas and fine-particle powders of two soft metals having lower hardness and lower melting point than the base material of a sliding contact portion is ejected onto a surface of the sliding contact portion. The fine-particle powders of the soft metals are made to react with oxygen in the compressed gas at the surface of the sliding contact portion to form a metal-oxide film with high melting point composed of metal oxides of the two soft metals, one of the metal oxides having higher hardness than the other. This metal-oxide film with high melting point includes a coating having a thickness of 0.

Abstract: An anti-seizure agent for hot steel working that exhibits excellent wettability and surface film-adherability comprises: an inorganic component (first component); sodium hydroxide (second component); water-soluble resins and/or water-soluble surfactants (third component); and water. With the mass of the sum of the first component, the second component, and the third component as 100 mass %, the anti-seizure agent contains: 96.5 mass % or more and 99.98 mass % or less of the first component; 0.01 mass % or more and 2.0 mass % or less of the second component; and 0.01 mass % or more and 1.5 mass % or less of the third component, and the inorganic component is one or more selected from a group consisting of Al2O3, SiO2, CaO, B2O3, K2O, and Na2O. A coating layer formed after application solidly adheres to the steel and does not come off in the environment of both cold and hot working.

Abstract: Provided is a grease composition with a long service life under high-temperature conditions, considerable low-evaporability, and incombustibility. The invention provides a grease composition comprising, as a base oil, an ionic liquid formed of a cation and an anion and having an ion concentration of 1 mol/dm3 or more as measured at 20° C., and a thickener having a dropping point of 260° C. or higher.

Abstract: Engines equipped with an exhaust line fitted with a particulate filter, in which the particulates contained in the exhaust gas are trapped on such filter, and wherein the trapped particulates are periodically burned off, are operated by improvedly catalyzing the combustion of said particles utilizing a composition containing mixture of a lubricating oil and a colloidal dispersion as the engine-lubricating composition, which dispersion includes particles of at least one compound of at least one rare earth and an amphiphilic agent.

Abstract: The present invention provides a beverage surfactant composition that includes a surfactant, a phosphonium compound, and a carrier; wherein the beverage surfactant composition exhibits stability as a solution or as a dispersion at a temperature of about 0 EC to about 8 EC. The present invention also provides a container or a conveyor for a container having a surface that is at least partially coated with the composition. The present invention also provides a process for lubricating a container that includes contacting at least a portion of a surface of the container and the composition together. The present invention also provides a process for lubricating a conveyor that includes contacting at least a portion of a surface of the conveyor and the composition together.

Abstract: A soft magnetic material includes a plurality of composite magnetic particles including a metal magnetic particle and an insulating film surrounding a surface of the metal magnetic particle. The insulating film also contains a phosphate. The soft magnetic material further includes an aromatic polyetherketone resin and a metallic soap and/or an inorganic lubricant having a hexagonal crystal structure. The metallic soap and the inorganic lubricant are particles with an average particle size of not more than 2.0 ?m.

Abstract: Improved desulfurization compositions are provided for removing substantial fractions of sulfur, sulfur complexes, and sulfur compounds from liquid hydrocarbons such as crude oil and fuels. The preferred compositions comprise respective quantities of an alkylphenol ethoxylate, an amine, and an alkali metal nitrite. The compositions may be contacted with liquid hydrocarbons to achieve high levels of desulfurization.

Abstract: A lube oil composition is provided. The lube oil composition includes a base oil and a carbon nanocapsule grafting with an alkyl group dispersed in the base oil, wherein the carbon nanocapsule is hollow or filled with metal, metal alloy, metal oxide, metal carbide, metal sulfide, metal nitride or metal boride.

Abstract: Lubricant-hard-ductile composite coating compositions and methods of making the same are provided. In embodiment, a composite coating composition comprises: a lubricant phase for providing lubrication to a surface; a hard ceramic phase for providing structural integrity and wear resistance to the surface; and a ductile metal phase for providing ductility to the surface.

Abstract: An additive mixture containing the components (A), (B) and optionally (C), wherein component (A) is at least one compound of the formula (I) wherein p is zero or 1; m and n are independently of one another an integer from zero to 3; and the radicals R are independently of one another C1-C8alkyl, C1-C8alkoxy, hydroxy, halogen, C1-C8alkylthio, C1-C8alkylsulfoxy or 2 radicals R form together with 2 adjacent carbon atoms of the unsaturated parent ring a 5- to 7-membered carbocyclic or heterocyclic ring; component (B) is at least one compound of the formula (II) wherein x and y are independently of one another an integer from 2 to 10; the radicals A1, A2 and A3 are independently of one another C1-C10alkyl, C5-C12cycloalkyl unsubstituted or substituted by 1 to 3 C1-C10alkyl; phenyl unsubstituted or substituted by 1 to 3 C1-C10alkyl; or C7-C12-phenylalkyl, and the radicals A2 and A3 are additionally hydrogen; with the proviso that at least one of the radicals A1 and A2 is branched C3-C10alkyl, C5-C12cycloa

Abstract: A gear part of the present invention includes a lubrication coating formed on a surface of the gear part, the lubrication coating containing an organic phosphorous compound. In the gear part, when a tooth surface of the gear part is engaged with a tooth surface of a counter member, the organic phosphorous compound is transferred to the tooth surface of the counter member and another lubrication coating containing the organic phosphorous compound is formed on the tooth surface of the counter member. As a result, the lubrication coating can be held on the surface of the gear part for long periods.

Abstract: A coating is provided having a first metal or non-metal nitride layer and a second metal or non-metal nitride layer wherein the first and second nitride layers are sufficiently resistant to interdiffusion to maintain respective individual layer structure and strength at an elevated operating temperature when a coating contact surface is in sliding contact with another material and wherein one of the first layer or second layer includes a component that is oxidizable at the contact surface to form a friction-reducing lubricous oxide material at the contact surface.

Abstract: The disclosed invention relates to a biodegradable grease composition. The grease composition comprises the reaction product of a dispersion of metal oxide and/or hydroxide particulates with at least one animal or vegetable oil. The dispersion comprises an organic medium and has a water content of up to about 0.5% by weight water. The particulates have a mean particle size up to about 15 microns. A process for making a grease composition using a dispersion of metal oxide and/or hydroxide particulates is disclosed.

Abstract: The present invention provides compositions and products, such as waxes and lubricants, comprising a plurality of nanoparticles dispersed in a continuous phase comprising a vegetable oil derived material, such as one or more vegetable oils or a synthetic product derived from one or more vegetable oils. Incorporation of nanoparticles in the present compositions is beneficial for providing mechanical, thermal and/or chemical properties useful for a selected product or product application. In some compositions of the present invention, for example, incorporation of the nanoparticle component provides compositions derived from one or more vegetable oils exhibiting enhanced mechanical stability, hardness, viscosity, thermal stability and mechanical strength.

Abstract: To provide a nanoparticle-containing lubricating oil composition which demonstrates a low friction coefficient and realizes a further fuel economy. A nanoparticle-containing lubricating oil composition comprising a base oil, an additive having hydroxyl group, and nanoparticle. A nanoparticle-containing lubricating oil composition comprising a base oil, an ashless friction modifier having hydroxyl group, and nanoparticle. A nanoparticle-containing lubricating oil composition comprising a base oil, an additive having hydroxyl group, and nanoparticle having a particle diameter of 1 to 100 nm. A nanoparticle-containing lubricating oil composition comprising a base oil, an ashless friction modifier having hydroxyl group, and nanoparticle having a particle diameter of 1 to 100 nm.

Abstract: An embodiment of the invention relates to a spindle motor of a magnetic recording storage device, the spindle motor comprising a fluid dynamic bearing comprising a lubricant comprising at least one of an organic and inorganic nanomaterial.

Abstract: [Object] To provide a nanoparticle-containing lubricating oil composition which demonstrates a low friction coefficient and realizes a further fuel economy. [Solving Means] A nanoparticle-containing lubricating oil composition comprising a base oil, an additive having hydroxyl group, and nanoparticle. A nanoparticle-containing lubricating oil composition comprising a base oil, an ashless friction modifier having hydroxyl group, and nanoparticle. A nanoparticle-containing lubricating oil composition comprising a base oil, an additive having hydroxyl group, and nanoparticle having a particle diameter of 1 to 100 nm. A nanoparticle-containing lubricating oil composition comprising a base oil, an ashless friction modifier having hydroxyl group, and nanoparticle having a particle diameter of 1 to 100 nm.

Abstract: The invention provides a process for preparing a dispersion of particles, by reducing in particle size at least one component by agitating the component in the presence of (i) a plurality of beads; (ii) a powder; (iii) a surfactant; and (iv) a liquid medium to form a dispersion, wherein the particles are uniformly dispersed in the liquid medium. The invention further provides for the use of the dispersion of particles.

Abstract: A composition that includes solid lubricant nanoparticles and an organic medium is disclosed. Also disclosed are nanoparticles that include layered materials. A method of producing a nanoparticle by milling layered materials is provided. Also disclosed is a method of making a lubricant, the method including milling layered materials to form nanoparticles and incorporating the nanoparticles into a base to form a lubricant.

Abstract: A waterborne composition for forming protective coatings to provide, by a simple method comprising coating and drying onto a metal surface, a coating that is uniform with little unevenness and that has an excellent galling resistance and workability that are at least as good as the corresponding properties afforded by conversion treatment methodologies, contains water-soluble inorganic salt and smectite-type clay mineral. The lubrication performance of the coating can also be improved when said composition additionally contains a lubricating component.

Abstract: A method for lubricating a metal workpiece during a metalworking process includes delivering supercritical carbon dioxide to the workpiece during the metalworking process. The supercritical carbon dioxide acts as a lubricant, coolant, chip evacuator, and/or carrier for another lubricant or corrosion inhibitor.

Abstract: There is provided a fluid composition comprising (a) one or more non-chlorinated 3-isothiazolone, (b) 0.7% to 10% by weight, based on the weight of said fluid composition, one or more primary alkanolamine, (c) 2% to 30% by weight, based on the weight of said fluid composition, one or more tertiary alkanolamine, (d) one or more stabilizer selected from the group consisting of iodine-containing stabilizers, mercaptobenzothiazole, and mixtures thereof, wherein the molar ratio of said stabilizer to said non-chlorinated 3-isothiazolone is from 0.3:1 to 3:1.

Abstract: The invention provides a method of lubricating an internal combustion engine comprising supplying to said engine a dispersion, the dispersion comprises: (a) a metal base; (b) a surfactant; and (c) an organic medium in which the metal base is uniformly dispersed by physical processes, wherein the metal base has a mean average particle size of at least 10 nanometres to less than 1 ?m; and the dispersion has a solids content of greater than 15 wt %. The invention further provides a lubricant composition containing said dispersion.

Abstract: The invention relates to a novel emulsified composition containing (a) major amount of an aqueous phase, (b) a minor amount of an organic phase (c) a thickener and (d) a minor but effective amount of at least one emulsifier to emulsify the aqueous and organic phase resulting in a water in oil emulsifeid composition, in particular emulsified greases and emulsified coatings. Further, the present invention provides a process for making the emulsified composition.

Abstract: A scroll compressor (10) includes a lubrication part (70) provided at a sliding part between a cylindrical part (26) of a slide bush (25) and an extension (53) of a movable scroll (50). The lubrication part (70) has a coating formed on the surface of an iron substrate and the coating is made of a composition for a sliding element containing polytetrafluoroethylene, 300 parts by weight of polyamide-imide resin per 100 parts by weight of polytetrafluoroethylene and 100 parts by weight of calcium fluoride as a wear resistant agent per 100 parts by weight of polytetrafluoroethylene.

Abstract: Lubricant oil compositions containing a base oil and an additive package comprising one or more wear-resistant additives. The wear-resistant additives can be (a) a Group 1a alkali metal carbonate, a Group 2a alkaline earth metal carbonate, or a mixture thereof; (b) Group 1a alkali metal sulfate, a Group 2a alkaline earth metal sulfate, or a mixture thereof; (c) a Group 1a alkali metal phosphate, a Group 2a alkaline earth metal phosphate, or a mixture thereof; (d) Group 1a alkali metal carboxylate, a Group 2a alkaline earth metal carboxylate; or (e) a combination of (a), (b), (c), and (d). The wear-resistant additives are in the form of nanoparticles.

Abstract: The present invention provides an emulsion composition containing (a) a first phase with (i) an oil soluble inert medium; and (ii) an emulsifier capable of forming a water-in-oil emulsion; and (b) a second phase with (i) a metal base; (ii) an aqueous medium; and (iii) optionally a compound containing two or more hydroxyl groups, wherein a base in the form of an alkali metal or an alkaline earth metal oxide, hydroxide, carbonate, bicarbonate; or combinations thereof; and wherein the emulsion composition has a flow rate through a 45 ?m filter of more than 8 ml/min in a filterability test carried out at ambient temperature and 45 kPa applied vacuum; wherein the filter has diameter of 5 cm and a mesh size of about 45 ?m; and wherein the oil soluble inert medium in the filtration test is an oil of lubricating viscosity of a SAE 50 base oil. The invention further provides a method of preparing the emulsion composition and its use in a marine engine.

Abstract: The present invention provides a grease composition capable of effectively preventing a rolling surface of a bearing from having hydrogen brittleness-caused peeling, a grease-enclosed bearing in which the grease composition is enclosed, and a rotation-transmitting apparatus with a built-in one-way clutch in which the grease composition is enclosed at a sliding portion. The grease composition contains a base grease consisting of a base oil and a thickener; and an additive added to the base grease. The grease composition prevents a frictional wear surface of the sliding portion or a newly generated surface consisting of iron or the like exposed owing to wear from being peeled owing to hydrogen brittleness. The additive contains a bismuth-based additive or a magnesium-based additive. The bismuth-based additive consists of at least one of inorganic bismuth and organic bismuth not containing a sulfur component. The magnesium-based additive consists of at least one of inorganic magnesium and organic magnesium.

Abstract: A waterborne lubricant, useful in the plastic working of metals, which imparts a lubricating behavior to the surface of metals in the absence of a conversion coating contains (A) water-soluble inorganic salt and (B) wax, wherein these components are dissolved or dispersed in water and the (B)/(A) solids weight ratio is 0.3 to 1.5. The (C) metal salt of a fatty acid can also be present at a (C)/(A) solids weight ratio of 0.01 to 0.4. The water-soluble inorganic salt (A) can be selected from the sulfates, silicates, borates, molybdates, and tungstates. The wax (B) can be a synthetic wax having a melting point of 70 to 150° C. A lubricating coating is formed by application to give a post-drying add-on of 0.5 to 40 g/m2. A method for using said lubricant is also provided.

Abstract: A method for lubricating a metal workpiece during a metalworking process includes delivering supercritical carbon dioxide to the workpiece during the metalworking process. The supercritical carbon dioxide acts as a lubricant, coolant, chip evacuator, and/or carrier for another lubricant or corrosion inhibitor.

Abstract: A non-chlorine type lubricant in which a sulfur type extreme pressure additive, an organic zinc compound, a calcium type additive, and an ester compound are blended with a base oil for the lubricant, and having a kinetic viscosity from 5 to 50 mm2/s at 40° C.

Abstract: A grease composition using lubricating base oil that is biodegradable by microorganisms in nature and has an affinity to the human body is provided. More particularly, a distillation residue secondarily generated in production of biodiesel from vegetable oil (soybean oil and canola oil) is used as the lubricating base oil. The grease composition is produced by adding 1 to 20 wt % of additives to 100 to 95 wt % of distillation residues, which is generated in production of biodiesel, and 1 to 30 wt % of thickeners.

Abstract: A method for reducing a friction coefficient adjacent a lubricated surface, and a lubricant composition for reducing a friction coefficient between lubricated surfaces. The method includes providing an amount of metal-containing dispersed in a fully formulated lubricant composition containing a base oil of lubricating viscosity, wherein the nanoparticles have an average particles size ranging from about 1 to about 10 nanometers. The lubricant composition containing the metal-containing nanoparticles is applied to a surface to be lubricated.

Abstract: A method of making a thermal spray powder is provided. The method comprises: providing a powder comprising a plurality of porous particles; infiltrating a mixture comprising a solvent and a plurality of solid lubricant particles into the porous particles; and heating the powder to a temperature sufficient to evaporate the solvent. The method of forming a wear-resistant coating is provided. The method comprises: providing a thermal spray powder; heating the thermal spray powder; and accelerating the thermal spray powder from a thermal spray gun onto the substrate, to form a deposit. Yet another embodiment provides a wear resistant coating. The wear resistant coating is formed by thermally spraying the thermal spray powder.

Abstract: The present invention relates to a lubricant for lubricating relatively movable, facing contact surfaces at least one of which is coated with DLC, a method of lubricating DLC contact surfaces with this lubricant, and a system having DLC contact surfaces. The lubricant fulfills the following conditions (a) and (b): (a) the lubricant contains a lubricant base oil containing, as a main component, a base oil composed at least one of a hydrocracked mineral oil, a wax-isomerized mineral oil, and a poly-?-olefin base oil. The base oil has a kinematic viscosity of 2 to 20 mm2/s at 100° C., a total aromatic content of not higher than 5 mass %, and a sulfur content of 0.005 mass %; and (b) the lubricant has a sulfur content of not higher than 0.2 mass %.