TWI448549B - Lubricant composition and lubricating system using same - Google Patents

Description

Lubricant composition and lubrication system using the same

The present invention relates to a lubricant composition which is semi-solid at normal temperature, and more particularly to a lubricant composition having a high extreme pressure property and stable friction characteristics. Furthermore, the present invention relates to a lubricating system in which the lubricant resistant composition is applied to a transmission element mechanism.

In recent years, environmental protection and energy conservation have become important key technologies. In particular, environmental protection issues include, for example, reduction in carbon dioxide emissions, power saving, energy conservation, and efficient use of resources. It can be used as a target area, and there are various production activities and transportation systems.

Various industrial machines, such as calenders, plastic processing machines, work machines, injection molding machines (injection.rnoulding machines), presses, forging presses, etc., of course require high precision processing and high reliability. In addition to sex, there is a strong demand for energy saving. Moreover, in terms of compressors and vacuum pumps, energy-saving operation is also required. In addition, in addition to comfortable and stable driving and navigation, the transportation systems represented by automobiles, construction machinery, agricultural machinery, trains, airplanes, and ships also need to save fuel and save energy. In addition, mechanical systems such as home appliances, OA (office automation) equipment, and precision machinery are also being developed to consider products that further save energy.

In these mechanical systems, a plurality of bearings, gears, motive screws, direct-drive tables, and Cam (cam), belt, chain, cable and other transmission components. Systems in which such components are properly assembled are also being applied. Bearings, there are: various rolling bearings, sliding bearings and so on. The gear can also be exemplified by a parallel shaft gear such as a spur gear or a helical gear, a cross shaft gear such as a face gear, a screw gear or a hypoid gear (hypoid). Asymmetrical shaft gears such as gears, worm gears, epicyclic gears, differential gears, and the like. A representative of a rnotive screw may be a slide screw or a rolling screw. Specific transmission element mechanisms can be exemplified by bearings, table rollers, and chain drives for calenders or plasticity processing machines used in the field of ironmaking and metal processing. (chain driving), gear coupling, etc., for machine tools, injection molding machines, presses, forging presses, grinders, etc. There are bearings, rnotive screws, gears, belts, chains, etc. Precision drive mechanism parts. The power train of the car has a constant velocity joint, a universal joint, and a bearing. In the periphery of the engine, an actuator, a starter, a gear, an alternator, and a bearing are used. In addition, the steering aspect is using electric steering, over-speed rack and pinion, tilt telescope, suspension ball joint (ball). Joint) lubrication of machinery, brakes or chassis, electrical equipment parts. For the electrical device mechanism, the door handle portion of the door, the door check, the door hinge, and the door lock actuator are used. (door lock actuator), door ratchet, key cylinder, electric mirror, seat belt, seat, door regulator, various switches (switch) various transmission component mechanisms. In addition, there are chain drive parts and bearings for automatic two-wheelers and bicycles. In the construction machinery of excavators, wheel loaders, bull dozers, cranes, etc., there are guide bushes, gears, bearings, and agricultural machinery. There are bearings, gears, and chain drive units in lawn mowers, chain saws, and the like. Further, in the railway system, there are shifting gears and rail track switching mechanisms, and in airplanes or ships, various bearings and gears are also provided. Furthermore, various video and audio information devices, such as CDs (CDs), DVDs (diversified digital optical discs), audio tapes, digital tapes, etc., as memory media, and such portable devices, printers, facsimile machines, copy machines, etc. OA equipment. Also in bearings, gears, direct-coupled screws, chain drives, hard disk drive units in computers, film cameras, digital cameras, etc. in home appliances such as air conditioners, refrigerators, vacuum cleaners, induction cookers, washing machines, and health massage machines. The shutter mechanism portion, the lens drive portion, and the gear mechanism of the timepiece can also be exemplified as the transmission element mechanism.

Among these transmission element mechanisms, various lubricating oils, lubricants, greases, solid lubricants, and combinations thereof are used depending on the application. In particular, greases are not susceptible to oil leakage, and products having properties required for each application have been developed and have been put into practical use. Further, a liquid lubricating base oil containing a mineral oil system and/or a synthetic system, a biguanide and/or a monodecylamine, and a A composition having a thermoreversible gel-like lubricity of a friction modifier (Patent Document 1).

However, in recent years, the above-mentioned mechanical system is strongly required to be highly functional, miniaturized, and durable, so that the lubricant is required to be further improved in performance, and in particular, even a very small amount of oil can be smoothly lubricated.

[Patent Document 1] WO (World Patent) 2006/051671

The present invention has been made to solve the above problems, and an object of the present invention is to provide a lubricant composition which can apply a very small amount of an oil agent to a lubricating sliding portion to exhibit a high resistance even in a thin film state. It has excellent lubricity such as pressure and stable friction characteristics, and is semi-solid at normal temperature, and provides a lubrication system using this lubricant composition for a conductive element mechanism.

In order to solve the above problems, the inventors of the present invention have finally achieved the present invention by focusing on the results of research on lubricating base oils, chemical substances which maintain lubricity, additives, and the like.

That is, the present invention is a lubricant composition and a lubrication system as described below.

(1) A lubricant composition characterized by containing 10 to 99.9% by mass of the liquid base oil, 0.1 to 90% by mass of the guanamine compound, and 1.0 to 20% by mass of the solid lubricant or based on the amount of molybdenum (Mo) It is an organic molybdenum compound of 0.0005 to 5% by mass, and is semi-solid at normal temperature.

(2) The lubricant composition according to (1) above, wherein the liquid base oil is selected At least one of a poly-α-olefin low polymer and a fatty acid ester.

(3) The lubricant composition according to the above (1) or (2), wherein the guanamine compound is at least one compound represented by the following general formulas (1) to (3).

R ¹ -CO-NH-R ² (1) R ³ -CO-NH-A ¹ -NH-CO-R ⁴ (2) R ⁵ -NH-CO-A ² -CO-NH-R ⁵ (3) (In the formulae (1) to (3), R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms, and R ² may be Is hydrogen, and A ¹ and A ² are a divalent hydrocarbon group having 1 to 10 carbon atoms selected from the group consisting of an alkylene group having 1 to 10 carbon atoms, a phenyl group or an alkyl group having 7 to 10 carbon atoms.

(4) The lubricant composition according to any one of the above aspects, wherein the solid lubricant is one or more selected from the group consisting of molybdenum disulfide, graphite, boron nitride, and fluorine-containing resin. By.

(5) The lubricant composition according to any one of the above (1), wherein the organic molybdenum compound is at least one of molybdenum dithiocarbamate and molybdenum dithiophosphate.

(6) A lubricating system characterized in that the lubricant composition according to any one of the above (1) to (5) is used in a transmission element mechanism.

(7) The lubrication system according to (6) above, wherein the transmission element mechanism includes at least one of a bearing, a gear, a transmission screw, a direct drive table, a cam, a belt, a chain, and a wire.

When the lubricant composition of the present invention is used and a small amount is applied to the lubricating sliding portion, a stable film can be formed during sliding and displayed for a long period of time. A special effect of excellent lubricity such as high resistance to extreme pressure and low frictional properties. Moreover, since it is a semi-solid lubricant composition at normal temperature, it can replace the general-purpose grease, and can be used as a bearing, a gear, a transmission screw, a direct linkage table, a cam, a belt, a chain, a wire rope, etc. The transmission element mechanism, in particular, is an effective user of the lubricant as a power steering device for automobiles.

[Best form for carrying out the invention]

The present invention is a lubricant composition characterized by containing 10 to 99.9% by mass of a liquid base oil, 0.1 to 90% by mass of a guanamine compound, and 1.0 to 20% by mass or 0.0005 to 5% by mass of a solid lubricant. When the molybdenum compound is used as a molybdenum (Mo) amount and is semi-solid at normal temperature, if it is applied to a transmission element mechanism that requires lubrication, when it is in a state requiring lubrication, it will become liquid and exhibit desired lubricating properties. . In particular, it is useful in low-speed, high-load operations where there is a need for seizuring troubles, and in operations requiring extreme pressure lubrication. It exhibits high lubricity under the film and excellent oil retention. It is difficult to break the oil, so sintering is not easy to occur. Further, the lubricating composition of the present invention functions as a lubricant composition when the sliding portion of the transmission element mechanism starts to operate, and the temperature of the sliding portion rises from a semi-solid state to a liquid state and enters a narrow sliding portion. However, since the portion that does not propagate the frictional heat away from the sliding portion remains in a semi-solid state, there is no need to worry about the so-called oil leakage and the surrounding cleaning can be kept constantly.

Here, "normal temperature" means the normal temperature in the room, specifically, It is 50 ° C or less, and more generally, it means a temperature environment of about -10 to 30 ° C.

[liquid base oil]

As the liquid base oil to be used in the present invention, mineral oil, synthetic oil or a mixed oil of these may be used. The characteristics of the liquid base oil are not particularly limited, but it is preferably a kinernatic viscosity at 40 ° C of 5 to 5000 mm ² /s, more preferably 10 to 1000 mm ² /s, and even more preferably 20 to 700mm ² / s. Further, the viscosity index is 90 or more, preferably 95 to 250, the pour point is below -10 ° C, preferably -15 to -70 ° C, and the flash point is 150. Above °C is appropriate.

In the case of mineral oil, it is suitable to use a crude oil which is distilled under normal pressure, and then the distilled lubricating oil fraction is subjected to solvent desolving process and solvent extraction under appropriate pressure. The refined lubricating oil fraction obtained by the lubricating oil purification means such as hydrogenation decomposition, solvent dewaxing process, hydrodewaxing, hydrorefining, sulfuric acid washing, and clay treatrnent treatment. A purified lubricating oil fraction different in properties obtained by a combination of various raw materials and various purification means may be used alone or in combination of two or more.

Further, the synthetic oil may, for example, be a poly-α-olefin (PAO) or a poly-α-olefin low polymer such as an ethylene-α-olefin low polymer, an alkyl petroleum naphthenic acid, an ethylene glycol or a fat. Acid esters, organic oils, fluoro oils, and the like. Among them, poly-α-olefins and fatty acid esters are superior in terms of viscosity characteristics, oxidation stability, material suitability, and cost. use. These synthetic oils may be used singly or in combination of two or more kinds as long as they can satisfy the above physical properties. Further, the above mineral oil and synthetic oil may be used in combination at any mixing ratio. At this time, a plurality of mineral oils and synthetic oils can be used separately.

Poly-α-olefins, which are chemically inert, are commercially available with excellent viscosity characteristics, a wide range of viscosities, and low cost. The poly-α-olefin is preferably polymerized by using a low-polymer polymerization of an olefin such as 1-pentene or 1-dodecene or 1-tetradecene, and the polymerization degree is in the range of 2 to 10, The polymer is suitably blended for viscosity adjustment.

Fatty acid esters are also commercially available in a variety of molecular structures, each with unique viscosity characteristics (high viscosity index, low flow point), such as high flash point when compared to hydrocarbon based base oils of the same viscosity. The base oil of the character. The fatty acid ester can be obtained by dehydration condensation reaction of an alcohol with a fatty acid, but in the present invention, in terms of chemical stability, a diester, a polyol ester, or a complex ester is suitable as a liquid. Base oil composition.

As the diester, an ester of a dibasic acid having 4 to 14 carbon atoms and an alcohol having 5 to 18 carbon atoms is suitable. Here, as the dibasic acid, adipic acid, sebacic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, etc. may be specifically exemplified, and adipic acid and sebacic acid are preferred. , azelaic acid. In the case of an alcohol, a monohydric alcohol having 6 to 12 carbons, particularly preferably a branched monohydric alcohol having 8 to 10 hydrocarbon groups. Specifically, 2-ethylhexanol, 3,5,5-trimethylhexanol, decyl alcohol, lauryl alcohol, oleyl alcohol, etc. are mentioned.

Further, as the polyol ester, neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane, bis(trimethylolpropane), and tris(3) are preferred. An ester of a hindered alcohol such as methylolpropane, isoamyltetraol, bis(isopentaerythritol) or tris(isopentaerythritol) and a fatty acid having 1 to 24 carbon atoms. The number of carbon atoms in the fatty acid is not particularly limited, and among the fatty acids having 1 to 24 carbon atoms, from the viewpoint of lubricity, it is preferably a carbon number of 3 or more, more preferably a carbon number of 4 or more, and more preferably carbon. Those with a number of 5 or more are particularly good for those having a carbon number of 7 or more. Specific examples thereof include valeric acid, caproic acid, heptanoic acid, caprylic acid, capric acid, capric acid, undecanoic acid, dodecanoic acid, tridecanoic acid, myristic acid, pentadecanoic acid, and hexadecane. Acid, heptadecanoic acid, octadecanoic acid, nonadecanic acid, eicosanic acid, etc., and these fatty acids may be any of linear fatty acids and branched fatty acids, and further It may also be a fatty acid (new acid) in which the α carbon atom is a quaternary carbon atom. Among them, shikimic acid (n-valeric acid), caproic acid (n-hexanoic acid), enanth acid (n-heptanoic acid), caprylic acid (n-octanoic acid), pelargonic acid (pelargonic acid) (n-decanoic acid), capric acid (n-decanoic acid), oleic acid (cis-9-octadecenoic acid), isovaleric acid (3-methylbutyric acid), 2-methylhexanoic acid 2-Ethylpentanoic acid, 2-ethylhexanoic acid and 3,5,5-trimethylhexanoic acid are suitable.

Further, a complex ester synthesized from a dibasic acid and a polyhydric alcohol with a monocarboxylic acid or a monohydric alcohol is also suitable. Mineral oil is a base oil that is more widely used, and has a good balance between cost surface, viscosity characteristics, and oxidation stability. Among these base oils, poly-α-olefins can be used as the base oil which is most excellent in the performance surface and the cost surface.

[guanamine compound]

The guanamine compound to be used in the present invention is a fatty guanamine compound having one or more guanamine groups (-NH-CO-), and a monoamine having one guanamine group represented by the following formula (1) and a formula (2) and (3) are bisguanamines having two guanamine groups.

R ¹ -CO-NH-R ² (1)

In the formula, R ¹ and R ² are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms, and R ² may be hydrogen.

R ³ -CO-NH-A ¹ -NH-CO-R ⁴ (2) R ⁵ -NH-CO-A ² -CO-NH-R ⁵ (3)

In the formulae (2) and (3), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms, and A ¹ and A ² are selected from carbon number 1. A divalent hydrocarbon group having 1 to 10 carbon atoms in the alkyl group, the phenyl group or the alkyl group having 7 to 10 carbon atoms in the alkyl group of 10 to 10. Further, when the phenylene group is a phenyl group, it may be a divalent hydrocarbon group in a form in which two or more of a phenyl group and an alkyl group and/or an alkyl group are bonded.

The monodecylamine compound is represented by the above formula (1), but a part of hydrogen constituting R ¹ and R ² may be substituted by a hydroxyl group. Specific examples of such a monoamine compound include saturated fatty amines such as laurylamine, palmitosamine, stearylamine, behen amide, and hydroxystearate, and oil oxime. An unsaturated fatty amide such as an amine or eruc amide, and a saturated or not stearyl stearylamine, an oil-based rutheniumamine, an oleyl stearylamine, a stearyl amide or the like Saturated long-chain fatty acids and substituted amides of long-chain amines.

Among these monoamine compounds, it is preferred that at least R ¹ and R ² of the formula (1) are independently a decylamine compound having 12 to 20 saturated chain hydrocarbon groups and/or at least R ¹ and R ² . One is a decylamine compound having an unsaturated chain hydrocarbon group having 12 to 20 carbon atoms, more preferably a mixture of two guanamine compounds. Further, an unsaturated oil-based monoamine compound having an unsaturated chain-bonded hydrocarbon group of 18 carbon atoms is preferred. Specifically, it is preferably oily amide or oil-based rutheniumamine, and a film is formed and held at the sliding portion to ensure film retention which is effective for releasing the sintering problem.

The diammonium compound is a compound represented by the above formula (2) or (3) in the form of an acid decylamine having a diamine or an acid decylamine having a dibasic acid. Further, in the formulae (2) and (3), R ³ , R ⁴ , R ⁵ and R ⁶ , and further, a hydrocarbon group represented by A ¹ and A ² may be partially substituted with a hydroxyl group (-OH).

The guanamine compound represented by the formula (2) may, for example, be specifically exemplified by ethyl bis-stearylamine, ethyl bis-isostearate, ethyl acetophenone, methylene bis-lauric acid. Indoleamine, hexamethylene bis-indoleamine, hexamethylene bis- stearylamine, m-xylylene bis- stearylamine, and the like. The guanamine compound represented by the formula (3) may, for example, be specifically N,N'-distearyl decylamine or the like.

Among these bis-amine compounds, R ³ and R ⁴ of the formula (2) and R ⁵ and R ⁶ of the formula (3) are each independently a carbon number in the same manner as in the case of the monoamine compound. The guanamine compound having 12 to 20 saturated chain hydrocarbon groups and/or at least one of R ³ and R ⁴ and R ⁵ and R ⁶ is a guanamine compound having 12 to 20 carbon atoms of unsaturated chain, more preferably two A mixture of guanamine compounds. Further, from the viewpoint of ensuring film holding property, an oleylamine having an unsaturated group-bonded hydrocarbon group having 18 carbon atoms having an unsaturated bond is preferred. Such a compound may, for example, be ethyl acesulfame or hexamethylene bis decylamine.

When the guanamine compound is uniformly mixed with the liquid base oil, it forms a gel-like lubricious composition at normal temperature. This composition is uniformly blended with a solid lubricant or an organic molybdenum compound to be described later to prepare a lubricant composition which is semi-solid (gel-like) at normal temperature in the present invention. Thus, the indoleamine compound, in addition to the semi-curing compound which causes the liquid base oil to be semi-cured (gelled) At the same time, the function of the object, while exhibiting the original lubricating properties of the lubricant composition, functions as a lubricant composition of the liquid after being melted by frictional heat. When considering a case where it is semi-solid at a normal temperature and a liquid state at a high temperature, the melting point of the applicable guanamine compound is preferably 50 to 200 ° C, more preferably 80 to 180 ° C, and further The molecular weight is preferably from 100 to 1,000, more preferably from 150 to 800.

In addition, due to the limitation of the design of the mechanical system, only a small amount of oil can be used under the sliding portion. In order to prevent sintering or the like in a severe lubrication environment, the oil agent needs to be strongly adsorbed. Attached to the sliding surface to hold the oil film. For this reason, an oily agent having adhesion is required, and in the present invention, it has been found that when the hydrocarbon group of the guanamine compound which is itself a semi-cured compound is unsaturated chain-like, the fact of adhesion can be increased. If the adhesion is increased, it can be applied to the sliding surface in a film-like manner, and the oil film is not easily broken and the lubricating performance is improved even in a severe lubricating environment. The unsaturated chain hydrocarbon group is preferably an alkenyl group having an unsaturated bond having 12 to 20 carbon atoms, particularly preferably a bis-amine compound having an oil group having an unsaturated bond at a carbon number of 18.

The guanamine compound is formulated to be 0.1 to 90% by mass contained in the lubricant composition which is semi-solid at normal temperature after completion. When the amount of the guanamine compound is 0.1% by mass or less, the composition of the gel cannot be formed at normal temperature. On the other hand, even if it is 90% by mass or more, it is too hard to handle the treatment, which is not preferable. A more preferable amount is 1 to 80% by mass.

[Solid lubricants and organic molybdenum compounds]

In the lubricant composition of the present invention, in order to achieve high lubricity, Then, the solid lubricant is formulated in an amount of 1.0 to 20% by mass or an organic molybdenum compound having a Mo content of 0.0005 to 5% by mass. It is especially suitable for both.

The solid lubricant which can be used in the lubricant composition of the present invention may, for example, be a molybdenum disulfide, a graphite or a boron nitride which is a layered structural compound, a further polyimine, or a polytetrafluoroethylene. A fluorine-containing resin such as (PTFE).

The solid lubricant is formulated in an amount of 1 to 20% by mass, preferably 2 to 10% by mass, based on the lubricant composition of the present invention. When the content is less than 1% by mass, it does not have a meaning of being blended with the solid lubricant, and even if it is more than 20% by mass, the effect equivalent to the increase in lubricity is not obtained and it is not stably dispersed in the base oil.

These solid lubricants can be used without any particular limitation in terms of particle size and the like, as long as they can be uniformly dispersed in the base oil in the form of fine particles, but it is preferably such that they are stably dispersed without being precipitated. A particle diameter of 0.01 to 100 μm, more preferably 0.1 to 10 μm. Further, those solid lubricants may be uniformly dispersed in a diluent oil or a diluent solvent in advance, and may be suitably used. Among these solid lubricants, a layered structure compound, particularly a molybdenum disulfide system, is more preferable because the lubricating film formed on the sliding portion can contribute to low friction characteristics in a highly efficient manner in a severe lubrication region.

The organic molybdenum compound which can be effectively used in the lubricant composition of the present invention may, for example, be molybdenum dithiocarbamate (MoDTC) or molybdenum dithiophosphate (MoDTP). These compounds may be used singly or in combination of two or more. In particular, if an inorganic molybdenum compound is used in combination with an organic molybdenum compound, a greater lubricity improving effect can be obtained. Therefore, it is better For the combination of molybdenum disulfide and MoDTC and/or MoDTP. The mixing ratio of the inorganic molybdenum compound to the organic molybdenum compound at this time is preferably from 0.5:1 to 150:1, more preferably from 1:1 to 20:1, based on the molybdenum atom.

When the inorganic molybdenum compound and the organic molybdenum compound are based on a molybdenum atom, the lubricant composition which is semi-solid at normal temperature after completion may preferably contain 0.02 to 20% by mass, particularly preferably 0.1. Up to 10% by mass. If the blending ratio is less than 0.02% by mass, the lubricity-improving effect cannot be obtained, and on the other hand, even if the blending exceeds 20% by mass, the lubricity improvement effect equivalent to the blending amount cannot be obtained, and may be added The amount is too large to be stably dissolved in the base oil and thus has an adverse effect.

[Modulation of lubricant composition]

The lubricant composition which is semi-solid at normal temperature in the present invention is not particularly limited, and may be prepared by uniformly mixing a liquid base oil, a guanamine compound, a solid lubricant, and an organic molybdenum compound in the above ratio. For example, a liquid base oil, a guanamine compound, a solid lubricant, and an organic molybdenum compound are separately metered, and the liquid base oil and the guanamine compound (semi-cured compound) are heated to a melting point or higher, and then a solid state is added in a liquid state. The lubricant and the organic molybdenum compound are uniformly stirred and cooled to form a semi-solid state. Since the molybdenum disulfide-based powder solid is difficult to uniformly mix in the liquid oil, it is difficult to uniformly disperse in the liquid because the molybdenum disulfide is an inert inorganic compound which is insoluble to the oil. Therefore, the molybdenum disulfide may be kneaded by mixing the liquid base oil or the organic molybdenum compound with the decylamine compound heated to a melting point or higher and then cooling the semi-solid composition to be uniformly mixed. A lubricant composition in which the components are semi-solid at normal temperature.

In the composition of the present invention, additives such as known extreme pressure agents, corrosion inhibitors, anti-wear agents, rust inhibitors, antioxidants, and antifoaming agents can be appropriately formulated. The extreme pressure agent and the anti-wear agent may, for example, be a zinc dialkyl dithiophosphate, a sulfur compound or a phosphorus compound, and the anticorrosive agent may, for example, be a thiadiazole derivative or The benzothiazole and its derivative, and the rust inhibitor may, for example, be a fatty acid partial ester, a metal sulfonate or a phosphorus compound, and the antioxidant may, for example, be a phenol type or an amine type. Examples of the compound and the antifoaming agent include an organic lanthanoid compound, a PMA (polymethacrylate) polymer, a pour point depressant, and a viscosity index improver, and examples thereof include a PMA polymer and the like. . Further, the various additives described above may be used in the form of a so-called additive package in which a plurality of additives are mixed in advance.

The lubricant composition of the present invention which is semi-solid at normal temperature, if it is suitable for a mechanical mechanism (sliding portion) requiring lubrication, is changed into a liquid state due to frictional heat during sliding, and penetrates into the sliding portion, and A solid surface constituting the sliding portion such as a metal or a resin forms a film to lubricate the sliding portion. When the sliding is stopped, the temperature is lowered, and the lubricant composition which is originally in a liquid state is restored to a semi-solid state (gel-like shape). Further, since the lubricant composition of the present invention has excellent friction characteristics such as high sintering load and low friction coefficient, it can maintain such excellent friction characteristics for a long period of time, and therefore is suitable for low speed and high in use. The extreme pressure operator of the load is also suitable for use in a sliding portion of a device that is difficult to replenish the lubricant or that is once unassembled after being assembled. Furthermore, the lubricant of the present invention The composition is capable of re-constructing the gel (semi-solid structure) even if the temperature rise and the stress caused by the use or non-use are repeated, so that contamination due to oil leakage can be avoided.

Therefore, in addition to being able to be fully used in place of the conventional grease, it can be suitably used for, for example, a transmission element mechanism of a bearing, a gear, a drive screw, a direct drive table, a cam, a belt, a chain, a wire rope, etc., especially a high load. The conductive element is on the mechanism. A particularly preferable use is a shifting gear composed of a worm wheel or a planetary gear, and the like, and various uses thereof include various conveying mechanical systems and power steering devices for automobiles.

[Examples]

Hereinafter, the present invention will be described in detail by way of examples, but the invention is not limited by the examples.

[liquid base oil]

The following three liquid base oils were used to prepare the lubricant compositions for the examples and the comparative examples.

Base oil A: Commercially available poly-α-olefin (PAO: SHF-400 manufactured by Mobil: viscosity grade VG400) Base oil B: VG100 mineral oil (Japan energy company 500 neutral (neutral oil)) Base oil C: fatty acid ester (Priolube 2087 complex ester manufactured by Unikema)

The physical properties of the three liquid base oils are shown in Table 1. Further, these liquid lubricating base oils are preliminarily formulated with additives such as antioxidants and anti-wear agents, and have basic properties as lubricating oils (antioxidation and anti-oxidation). Wear and tear, etc.).

[guanamine compound]

The liquid base oil was formulated and the following guanamine compound was used for semi-curing.

Indoleamine A: ethylene bis-indolylamine (made by Nippon Kasei Co., Ltd., Simpsons O), melting point 119 ° C Indoleamine B: N-stearyl stearylamine (manufactured by Nippon Chemical Co., Ltd., ruthenium sulphate s), melting point 95 ° C

[Solid lubricant]

As the solid lubricant, the following two compounds were used.

MoS ₂ : molybdenum disulfide, particle size 1 μm, Mo content 60% by mass, PTFE: polytetrafluoroethylene particles KD-300AS (made by Kitamura), particle size 0.3 μm, diluted with mineral oil, PTFE concentration 40%

[organic molybdenum compound]

MoDTC: Adeka Sakura Lube 515 (manufactured by Adeka), Mo amount 10% by mass, dynamic viscosity (40 ° C) 700 mm ² /s.

[Modulation of lubricant composition]

As the liquid base oil, base oil A (PAO) and base oil B (mineral oil) are used, and as the guanamine compound, guanamine A (ethylene bisamine) and guanamine B (N-stearyl group hard) are used. Lipidamide), and MoS ₂ (molybdenum disulfide) and MoDTC (molybdenum dithiocarbamate) were used as the molybdenum compound, and the test oils of Examples 1 to 10 and Comparative Examples 1 and 2 were prepared in the following procedure. (Lubricant composition).

In a stainless steel beaker, the ratio of the liquid base oil, the guanamine compound, and the molybdenum compound to the test oil after the completion of the test oil shown in the upper part of Table 2 (% by mass) can be obtained as about 100 ml of the test oil. The amount is measured by a predetermined amount, and the table electromagnetic heater is used, and the mixture is stirred while being heated to a temperature higher than the melting point of the guanamine compound (melting point + 20 ° C). After the appearance was observed to be uniformly dissolved, about 100 ml of the homogeneous solution was transferred to a heat-resistant glass container (inner diameter 60 rnm x height 90 mrn) and allowed to cool, and Examples 1 to 10 and Comparative Examples 1 and 2 were semi-solid at normal temperature. a lubricant composition.

A commercially available lithium (Li) grease which has been conventionally used as a semi-solid lubricant composition was evaluated as a comparative object (Comparative Example 2). The grease contains a Mo-based additive (7% in terms of Mo), and the consistency of the grease is equivalent to the consistency number No. 2 (mixed consistency range 265 to 295).

[Evaluation method]

Each of the lubricant composition of the examples and the comparative examples and the Li grease evaluation test (measurement of the sintering load and the friction coefficient) were carried out according to the method described below. The results are shown in the lower part of Table 2.

(1) FALEX sintering test The measurement of the sintering load according to the combination of a block and a pin was carried out using a FALEX tester described in ASTM D3233. The material of the V block and the pin is AISI (American Iron and Steel Institute) steel. The measurement was started under the conditions of a number of revolutions of 300 rpm, a continuous load, and room temperature. The general evaluation is carried out in the state where the block/pin is completely immersed in the test oil, but in this evaluation, only the V-shaped portion (triangular column) of the two V-shaped blocks is coated with the test oil. And record the sintering load when a small amount of test oil is used. Here, the supply of the test oil in the test was not carried out.

(2) HFRR test The friction coefficient was measured using an HFRR tester (HFRR D-826 manufactured by PCS Instruments Co., Ltd.) prescribed in JPI-5S-50-98 (Petroleum Society Standard, Light Oil-Lubricity Test Method). The material is SUJ (high carbon chromium bearing steel)-2. The disk has a diameter of 9 mm and a thickness of 5 mm, and the material is SUJ-2. The test oil was applied to the surface of the disk so as to be extremely thin so as to have a coating amount of 0.0003 g/cm ² . The test was carried out for 10 minutes of round-trip friction according to a load of 300 gf, an amplitude of 50 Hz, an amplitude of 1.0 mm, and a temperature of 25 °C.

Examples 1 to 10 exhibited a sintering load of 1500 to 2100 LBF (lbs) at FALEX and showed a high extreme pressure resistance. In contrast, the sintering load in Comparative Examples 1 and 2 was lower than that in the examples. Further, in the HFRR test, the friction coefficients of Examples 1 to 10 showed stable values of, for example, 0.12 to 0.14, but in the comparative example, sintering occurred in a friction time of less than 10 minutes. From the above results, in the examples, even a very small amount of the oil agent can exhibit a high extreme pressure resistance, and even if it is applied in the form of a film, a strong friction coefficient can be formed.

[Industrial availability]

As apparent from the above, the lubricant composition which is semi-solid at normal temperature in the present invention is a general-purpose grease which can be formed into a film state with a very small amount of use, and exhibits high extreme pressure resistance and stable friction characteristics. Particularly stable friction characteristics (low coefficient of friction) are beneficial to energy saving. Therefore, if it is applied to a transmission element mechanism, for example, a mechanical system formed by a mechanism such as a bearing, a gear, a transmission screw, a cam, a belt, a chain, a cable, etc., energy saving can be achieved, and due to the extreme pressure resistance Extremely high, it can be expected to contribute to the durability of mechanical systems.

Claims (6)

A lubricant composition characterized by containing 10% by mass or more of a liquid base oil, the remainder being 0.1 to 80% by mass of a guanamine compound, and 1.0 to 20% by mass of a solid lubricant or by weight of molybdenum (Mo) 0.0005 to 5% by mass of the organic molybdenum compound, which is semi-solid at normal temperature, and the guanamine compound contains both the compound represented by the following general formula (1) and the compound represented by the general formula (2), R ¹ -CO -NH-R ² (1) R ³ -CO-NH-A ¹ -NH-CO-R ⁴ (2) (In the formulae (1) and (2), each of R ¹ , R ² , R ³ and R ⁴ Independently, a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms, R ² may be hydrogen, and A ¹ is selected from an alkyl group having 1 to 10 carbon atoms, a phenyl group or an alkyl group having a carbon number of 7 to 10. a divalent hydrocarbon group having 1 to 10 carbon atoms of a phenyl group). The lubricant composition according to claim 1, wherein the liquid base oil is at least one selected from the group consisting of poly-α-olefin low polymers and fatty acid esters. The lubricant composition according to the first aspect of the invention, wherein the solid lubricant is one or more selected from the group consisting of molybdenum disulfide, graphite, boron nitride, and fluorine-containing resin. The lubricant composition according to claim 1, wherein the organic molybdenum compound is at least one selected from the group consisting of molybdenum dithiocarbamate and molybdenum dithiophosphate. A lubricating system characterized in that the lubricant composition according to any one of claims 1 to 4 is used in a transmission element mechanism. The lubrication system of claim 5, wherein the transmission component mechanism comprises at least one of a bearing, a gear, a transmission screw, a direct drive table, a cam, a belt, a chain, and a steel cable.