JP2019206671A - Lubricant composition and method for producing the same, lubrication method for drive system equipment and drive system equipment - Google Patents

Abstract

To provide a lubricant composition having excellent wear resistance and oxidation stability and a method for producing the same, and a lubrication method for drive system equipment, and drive system equipment, each of which uses the lubricant composition.SOLUTION: The present invention provides a lubricant composition containing a base oil, and a specific phosphorus-containing compound, and a method for producing the same; and a lubrication method for drive system equipment, and drive system equipment, each of which uses the lubricant composition.SELECTED DRAWING: None

Description

  The present invention relates to a lubricating oil composition and a method for producing the same, a method for lubricating a drive system device, and a drive system device.

  Lubricating oil compositions used for various applications such as shock absorbers, transmissions, power steering and other drive system devices, engines, hydraulic operations, and the like are required to have characteristics corresponding to each application. The characteristics of the lubricating oil composition are often greatly affected by the properties of the base oil used, the type of additive, etc., and in order to produce a lubricating oil composition that can exhibit the required characteristics, the base oil and The development of additives and the development of these formulations are widely performed.

  For example, parts such as sliding bearings and piston rings are incorporated in drive systems such as shock absorbers and transmissions used in automobiles such as automobiles and two-wheeled vehicles, and earthquake-resistant mechanisms in houses. Lubricating oil composition is used for lubrication of the sliding part which arises. The lubricating oil composition used in the shock absorber not only has the ability to lubricate the sliding parts of the above parts in the shock absorber, but also fills the shock absorber and creates fluid resistance when the piston expands and contracts. Therefore, the performance of attenuating the vibration transmitted from the road surface to the vehicle body in the case of a shock absorber for an automobile and the vibration due to an earthquake or the like is required for a shock absorber for a house. For example, in an automobile shock absorber, a sliding bearing is called a bush in the shock absorber industry, and is a component that slides with a piston rod. By optimizing the friction characteristics at the sliding parts such as between the piston rod and bushing and between the inner tube and piston ring, the ride quality of the automobile is controlled and the friction and wear of the parts are prevented, resulting in durability. It will be.

  Lubricating oil compositions used in drive system equipment such as shock absorbers, transmissions and the like in which parts with sliding parts such as sliding bearings and piston rings are incorporated have wear resistance particularly as a performance to lubricate sliding parts. Desired. As a lubricating oil composition having such performance, for example, a lubricating oil composition in which an antiwear agent such as zinc dialkyldithiophosphate (ZnDTP) is blended with a base oil, or a dioleyl hydrogen phosphite is blended with a lubricating base oil. In addition, a lubricating oil composition for automobile shock absorbers has been proposed (see, for example, Patent Document 1) containing an acidic phosphite diester such as dilauryl hydrogen phosphite.

JP 2003-147379 A

  By the way, self-lubricating polytetrafluoroethylene (hereinafter sometimes referred to as “PTFE”) material is sometimes used for parts such as a sliding bearing and a piston ring. For example, a PTFE coating is applied to a bronze sintered material. There are a sliding bearing, a piston ring made of PTFE material, and the like. Since PTFE material itself is a soft material, reinforcing materials such as glass fiber, graphite, and carbon fiber are blended, and the durability of the drive system equipment due to wear caused by these reinforcing materials at the sliding portion. In some cases, a problem such as lowering may occur. The decrease in durability is, for example, that the gap between the sliding portions becomes wider as the wear amount increases due to wear in the sliding direction on the inner tube contacting the piston ring made of PTFE mixed with glass fiber as a reinforcing material. Therefore, the damping performance is lowered, and as a result, the performance of the shock absorber is impaired. Therefore, in order to improve the durability of a drive system device such as a shock absorber, it is important to improve the wear resistance of the lubricating oil composition and suppress the occurrence of wear marks at the sliding portion.

  The lubrication of the sliding part in the drive system equipment includes the lubrication between the metal and the sliding part of the part using the PTFE material, that is, the lubrication of the PTFE material including the reinforcing material and the metal. Also, lubrication of sliding parts such as sliding bearings, piston rings, etc. includes lubrication in the state where the piston rod, inner tube and other parts in the vicinity of the center of the sliding part are continuously moving, and the end of the sliding part. There are mainly two types of lubrication, lubrication in a state where the part starts moving from a stopped state. Therefore, the lubricating oil composition is required to have wear resistance that can cope with these different types of lubrication.

  In addition, with the increase in size of automobiles (increase in displacement) and performance improvement, lubricating oil compositions used for these are required to have high oxidation stability. Various new transmissions have been developed, including manual transmissions, automatic transmissions, belt-type continuously variable transmissions, chain-type continuously variable transmissions, and dual transmissions. In order to develop a lubricating oil composition suitable for such transmissions, it is necessary to incorporate a number of additives. When an additive is added, the oxidation stability generally tends to deteriorate, so it is necessary to add an additive that improves the oxidation stability or to select an additive that does not deteriorate the oxidation stability. Depending on the type of additive used in the lubricating oil composition for shock absorbers, there are those that deteriorate the oxidation stability. In that case, an additive that improves the oxidation stability is added, or the oxidation stability is deteriorated. It is necessary to select additives that are not allowed.

  However, a lubricating oil composition in which an antiwear agent such as zinc dialkyldithiophosphate (ZnDTP) is blended with a base oil is effective for oxidation stability, but it is resistant to wear resistance, particularly galling marks at the sliding end. It is inferior in wear resistance. Moreover, although the lubricating oil composition in which acidic phosphorous acid diesters such as dioleyl hydrogen phosphite and dilauryl hydrogen phosphite described in Patent Document 1 are blended has an effect on wear resistance, It is inferior in oxidation stability. As described above, there is no conventional lubricating oil composition that has a high level of both wear resistance and oxidation stability.

  The present invention has been made in view of the above circumstances, and a lubricating oil composition having excellent wear resistance and oxidation stability, a method for producing the same, a method for lubricating a drive system device using the lubricating oil composition, and driving The purpose is to provide system equipment.

  As a result of intensive studies in view of the above problems, the present inventors have found that the above problems can be solved by the following invention. That is, this invention provides the outstanding lubricating oil composition which has the following structure, its manufacturing method, the lubricating method of a drive system apparatus using this lubricating oil composition, and a drive system apparatus.

1. A lubricating oil composition comprising a base oil and a phosphorus-containing compound represented by the following general formula (1).

(In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ represents Indicates an integer of 1 or 2.)
2. The manufacturing method of the lubricating oil composition which mix | blends base oil and the phosphorus containing compound represented by following General formula (1).

(In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ represents Indicates an integer of 1 or 2.)
3. A method for lubricating a drive system device using the lubricating oil composition described in 1 above.
4). A drive system device using the lubricating oil composition described in 1 above.

  ADVANTAGE OF THE INVENTION According to this invention, the lubricating oil composition excellent in abrasion resistance and oxidation stability, its manufacturing method, the lubricating method of a drive system apparatus using this lubricating oil composition, and a drive system apparatus can be provided.

  Hereinafter, an embodiment of the present invention (hereinafter simply referred to as “this embodiment”) will be described. In addition, in this specification, the numerical value concerning "above", "below", and "-" regarding description of a numerical range is a numerical value which can be combined arbitrarily.

[Lubricating oil composition]
The lubricating oil composition of the present embodiment contains a base oil and a phosphorus-containing compound represented by the following general formula (1). Hereinafter, components that can be contained in the lubricating oil composition of the present embodiment will be specifically described.

(In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ represents Indicates an integer of 1 or 2.)

(Phosphorus-containing compound)
The lubricating oil composition of this embodiment is required to contain a phosphorus-containing compound represented by the following general formula (1) (hereinafter sometimes simply referred to as “phosphorus-containing compound”). If the lubricating oil composition of the present embodiment does not contain a phosphorus-containing compound, excellent wear resistance and oxidation stability cannot be obtained at the same time. Here, in terms of wear resistance, the wear resistance to lubrication near the center of the sliding part (the ability to suppress wear marks) and the wear resistance to lubrication at the end of the sliding part (to suppress the occurrence of galling marks) Performance) and both. Further, the excellent wear resistance is not limited to the material related to the sliding part, that is, the material related to the sliding part is not limited to metal-metal, but is a PTFE material-metal mixed with a reinforcing material. Also means excellent wear scar generation suppression performance and galling scar generation suppression performance. Therefore, the lubricating oil composition of the present embodiment contains the above phosphorus-containing compound, so that it does not depend on the material related to the sliding part, and the performance of suppressing the occurrence of two marks having different properties, i.e., wear marks and galling marks. In addition to excellent wear resistance that simultaneously exhibits generation suppression performance, it can also have oxidation stability.

In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ is 1 Or the integer of 2 is shown.

As the monovalent hydrocarbon group for R ¹¹ , an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and the like are preferable from the viewpoint of improving wear resistance and oxidation stability. An aliphatic hydrocarbon group of an alkyl group is more preferable, an alkyl group or an alkenyl group is further preferable, and an alkyl group is particularly preferable. When these monovalent hydrocarbon groups are alkyl groups or alkenyl groups, they may be either linear or branched, but from the viewpoint of improving wear resistance and oxidation stability, branched ones may be used. preferable. In addition, the cycloalkyl group and the aryl group may be a polycyclic group such as a decalyl group, a naphthyl group, or a group having a bicyclo ring.

These monovalent hydrocarbon groups are those having a substituent containing an oxygen atom and / or a nitrogen atom such as a hydroxyl group, a carboxy group, an amino group, an amide group, a nitro group, a cyano group, a nitrogen atom, an oxygen atom, It may be partially substituted with a halogen atom or the like, and when the monovalent hydrocarbon group is a cycloalkyl group or an aryl group, it may further have a substituent such as an alkyl group or an alkenyl group. .
In addition, when n ₁₁ is 2, a plurality of R ¹¹ monovalent hydrocarbon groups may be the same or different, and are the same from the viewpoint of improving wear resistance and oxidation stability and availability. It is preferable that

The number of carbon atoms of the monovalent hydrocarbon group R ¹¹ is a case where an organic group containing a hydroxyl group X ¹¹ to be described later is represented by -R 12 ^OH, when the monovalent hydrocarbon group is an alkyl group From the viewpoint of improving wear resistance and oxidation stability, it is preferably 3 or more, more preferably 4 or more, still more preferably 6 or more, and the upper limit is preferably 20 or less, more preferably 16 or less, and still more preferably 10 When the monovalent hydrocarbon is an alkenyl group, it is preferably 2 or more, more preferably 3 or more, still more preferably 6 or more, and the upper limit is preferably 20 or less, more preferably 16 or less, still more preferably 10 or less. When the monovalent hydrocarbon is a cycloalkyl group, the carbon number is preferably 5 or more and 20 or less, and when the monovalent hydrocarbon is an aryl group, the carbon number is preferably 6 or more and 20 or less.

The carbon number of the monovalent hydrocarbon group of R ¹¹ is the case where X ¹¹ described later is an organic group represented by —OR ¹³ , and when the monovalent hydrocarbon group is an alkyl group, the wear resistance From the viewpoint of improving oxidation stability, it is preferably 1 or more, and the upper limit is preferably 12 or less, more preferably 6 or less, still more preferably 3 or less, preferably when the monovalent hydrocarbon is an alkenyl group. Is 2 or more, and the upper limit is preferably 12 or less, more preferably 6 or less, and still more preferably 4 or less. When the monovalent hydrocarbon is a cycloalkyl group, the carbon number is preferably 5 or more and 20 or less, and when the monovalent hydrocarbon is an aryl group, the carbon number is preferably 6 or more and 20 or less.

X ¹¹ represents an organic group containing an oxygen atom and having 1 to 30 carbon atoms. As represented by the general formula (1), the phosphorus-containing compound used in the present embodiment is an organic group in which all groups linked to the phosphorus atom include oxygen atoms (oxygen bonded through a double bond). (Excluding atoms). By using a phosphorus-containing compound having such a structure, excellent wear resistance and oxidation stability can be obtained.
Further, the X ^11, oxygen X ¹¹ comprises an oxygen atom, and unless an organic group having 1 to 30 carbon atoms, can not be obtained excellent oxidation stability, also be linked via a double bond to the phosphorus atom Without an atom, excellent oxidation stability cannot be obtained.

The organic group containing an oxygen atom of X ¹¹ and having 1 to 30 carbon atoms is, for example, —R ¹² OH (R ¹² has 1 to 30 carbon atoms) from the viewpoint of improving wear resistance and oxidation stability. An organic group containing a hydroxyl group represented by (hereinafter, referred to simply as “an organic group containing a hydroxyl group”), —OR ¹³ (R ¹³ has 1 to 30 carbon atoms). An organic group represented by the following monovalent hydrocarbon group (hereinafter sometimes referred to as a “hydrocarbyloxy group”), —R ¹⁴ —O—R ¹⁵ (R ¹⁴ has 1 or more carbon atoms) Preferable is an organic group having an ether bond represented by a divalent hydrocarbon group having 30 or less and R ¹⁵ is a monovalent hydrocarbon group having 1 to 30 carbon atoms. Among them, an organic group containing a hydroxyl group and a hydrocarbyloxy group are preferable. An organic group containing a hydroxyl group is preferable when it is desired to obtain further excellent wear resistance. Groups are preferred.

In —R ¹² OH of the organic group of X ¹¹ , R ¹² represents a divalent hydrocarbon group having 1 to 30 carbon atoms, and in —OR ¹³ of the organic group of X ¹¹ , R ¹³ is 1 or more carbon atoms. 30 or less monovalent hydrocarbon groups are shown.
When n ₁₁ is 1, the plurality of organic groups of X ¹¹ may be the same or different, and are preferably the same from the viewpoint of improving wear resistance and oxidation stability and availability. In addition, when the organic group of X ¹¹ is a hydrocarbyloxy group, the three hydrocarbyloxy groups linked to the phosphorus atom may be the same or different. From the viewpoint of improving wear resistance and oxidation stability, and availability. Are preferably the same.

Examples of the divalent hydrocarbon group for R ¹² include groups in which one hydrogen atom has been removed from the groups exemplified as the monovalent hydrocarbon group for R ¹¹ , that is, alkylene groups, alkenylene groups, cycloalkylene groups, arylene groups, and the like. Is preferred. Among these, from the viewpoint of improving wear resistance and oxidation stability, an alkylene group and an alkenylene group are preferable, and an alkylene group is more preferable. The alkylene group and alkenylene group may be either linear or branched, but are preferably linear from the viewpoint of improving wear resistance and oxidation stability.

The carbon number of the divalent hydrocarbon group of R ¹² is preferably 1 or more when the divalent hydrocarbon group is an alkylene group from the viewpoint of improving wear resistance and oxidation stability, and preferably as an upper limit. It is 12 or less, more preferably 8 or less, still more preferably 3 or less, and particularly preferably 2 or less. When the divalent hydrocarbon group is an alkenylene group, the number is preferably 2 or more, and the upper limit is preferably 12 or less, more preferably 8 or less, and still more preferably 3 or less. When the divalent hydrocarbon is a cycloalkylene group, the carbon number is preferably 5 or more and 20 or less, and when the monovalent hydrocarbon is an arylene group, the carbon number is preferably 6 or more and 20 or less.

Examples of the monovalent hydrocarbon group having 1 to 30 carbon atoms of R ¹³ include the same groups as those exemplified as the monovalent hydrocarbon group of R ¹¹ from the viewpoint of improving wear resistance and oxidation stability. Preferably mentioned. Among these, from the viewpoint of improving wear resistance and oxidation stability, an alkyl group and an alkenyl group are preferable, and an alkenyl group is more preferable.

When the monovalent hydrocarbon group is an alkyl group, the carbon number of the monovalent hydrocarbon group for R ¹³ is preferably 4 or more, more preferably 7 or more, from the viewpoint of improving wear resistance and oxidation stability. More preferably, it is 12 or more, More preferably, it is 16 or more, As an upper limit, Preferably it is 24 or less, More preferably, it is 22 or less, More preferably, it is 20 or less. When the monovalent hydrocarbon is an alkenyl group, it is preferably 4 or more, more preferably 7 or more, still more preferably 12 or more, still more preferably 16 or more, and the upper limit is preferably 24 or less, more preferably 22 or less, More preferably, it is 20 or less. When the monovalent hydrocarbon is a cycloalkyl group, the carbon number is preferably 5 or more and 20 or less, and when the monovalent hydrocarbon is an aryl group, the carbon number is preferably 6 or more and 20 or less.

The divalent hydrocarbon group R ^14, those exemplified as the divalent hydrocarbon groups of R ¹² are preferably exemplified, and as the monovalent hydrocarbon group of R ^15, the R ¹³ What was illustrated as a monovalent hydrocarbon group is mentioned preferably.

When X ¹¹ is an organic group containing a hydroxyl group and n ₁₁ is 1, the phosphorus-containing compound becomes a phosphinic acid ester having a structure in which one hydrocarbyloxy group and two organic groups containing a hydroxyl group are linked to a phosphorus atom. , N ₁₁ is 2, it becomes a phosphonic acid ester having a structure in which two hydrocarbyloxy groups and an organic group containing one hydroxyl group are linked.
When X ¹¹ is an organic group containing a hydroxyl group, n ₁₁ may be either 1 or 2, but from the viewpoint of improving wear resistance and oxidation stability, n ₁₁ is preferably 2. That is, when X ¹¹ is an organic group containing a hydroxyl group, the phosphorus-containing compound is preferably a phosphonic acid ester having two hydrocarbyloxy groups and an organic group containing one hydroxyl group. In this case, from the viewpoint of improving wear resistance and oxidation stability, it is preferable that the carbon number of R ¹¹ is larger than the carbon number of R ¹² .

When X ¹¹ is a hydrocarbyloxy group, the phosphorus-containing compound has a structure in which three hydrocarbyloxy groups are linked to a phosphorus atom (phosphate ester). In this case, n ₁₁ may be either 1 or 2, but it is preferable that n ₁₁ is 2 and R ¹³ has more carbon atoms than R ¹¹ .

  The phosphorus-containing compound represented by the general formula (1) includes a phosphinic acid ester having an organic group containing one hydrocarbyloxy group and two hydroxyl groups, an organic group containing two hydroocarbyloxy groups and one hydroxyl group. Phosphonic acid esters having three hydrocarbyloxy groups, and phosphones having two hydroocarbyloxy groups and an organic group containing one hydroxyl group from the viewpoint of improving wear resistance and oxidation stability. An acid ester and a phosphate ester having three hydrocarbyloxy groups are preferred. Among them, a phosphonic acid ester is preferred when it is desired to obtain further superior wear resistance, and a further superior oxidation stability is desired. Phosphate esters are preferred.

  In the present embodiment, the phosphorous compound may be selected from phosphinic acid ester, phosphonic acid ester, and phosphoric acid ester according to desired performance. As the phosphorus-containing compound, a kind of phosphinic acid ester, phosphonic acid ester, and phosphoric acid ester may be used, or a plurality of phosphinic acid esters, phosphonic acid esters, and phosphoric acid esters may be used. You may use it in combination.

  The content of the phosphorus-containing compound based on the total amount of the composition is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and still more preferably 0, from the viewpoint of further improving the wear resistance and oxidation stability. The upper limit is preferably 3.0% by mass or less, more preferably 2.0% by mass or less, and still more preferably 1.0% by mass or less.

(Base oil)
The base oil contained in the lubricating oil composition of the present embodiment may be either mineral oil or synthetic oil.
Mineral oil includes atmospheric residual oil obtained by atmospheric distillation of paraffinic, naphthenic and intermediate-based crude oil; distillate obtained by vacuum distillation of the atmospheric residual oil; Mineral oil refined by subjecting the oil to one or more of solvent removal, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, etc., for example, light neutral oil, medium neutral oil Examples thereof include mineral oils obtained by isomerizing oils, heavy neutral oils, bright stocks, and waxes (GTL waxes) produced by the Fischer-Tropsch process or the like.
Further, the mineral oil may be classified into any of groups 1, 2, and 3 in the API (American Petroleum Institute) base oil category, but from the viewpoint of further suppressing sludge formation, Those classified into 3 are preferred.

  Synthetic oils include, for example, polyα-olefins such as polybutene, ethylene-α-olefin copolymer, α-olefin homopolymer or copolymer; various types such as polyol ester, dibasic acid ester, and phosphate ester. Examples include ester oils; various ethers such as polyphenyl ether; polyglycols; alkyl benzenes;

  In the present embodiment, the base oil may be at least one mineral oil, at least one synthetic oil, or a mixed oil obtained by mixing at least one mineral oil and at least one synthetic oil. In the present embodiment, mineral oil is preferable from the viewpoint of being inexpensive and obtaining more excellent viscosity characteristics.

The viscosity of the base oil is not particularly limited, but from the viewpoint of preventing seizure at high temperatures, the 40 ° C. kinematic viscosity is preferably 3.0 mm ² / s or more, more preferably 4.0 mm ² / s or more, 5 0.0 mm ² / s or more is more preferable. From the viewpoint of securing low-temperature fluidity, is preferably from 30.0 mm ² / s, more preferably not more than 20.0 mm ² / s, more preferably not more than 10.0 mm ² / s. From the same viewpoint as this, 100 ° C. kinematic viscosity of the base oil is preferably at least 1.0 mm ² / s, more preferably at least 1.5 mm ² / s, more preferably more than 2.0 mm ² / s. The upper limit is preferably not more than 15.0 mm ² / s, more preferably not more than 10.0 mm ² / s, more preferably not more than 5.0 mm ² / s. The viscosity index of the base oil is preferably 70 or more, more preferably 71 or more, and still more preferably 72 or more. In this specification, kinematic viscosity and viscosity index are values measured using a glass capillary viscometer in accordance with JIS K 2283: 2000. When the kinematic viscosity and the viscosity index of the base oil are within the above ranges, the lubricating oil composition has more appropriate viscosity characteristics, and wear resistance and oxidation stability are improved.

Further, the 15 ° C. density of the base oil is preferably 0.80 g / cm ³ or more, more preferably 0.82 g / cm ³ or more, and still more preferably, from the viewpoint of exerting more appropriate lubricating performance as the lubricating oil composition. and at 0.83 g / cm ³ or more, preferably the upper limit is 0.95 g / cm ³ or less, more preferably 0.93 / cm ³ or less, further preferably 0.88 g / cm ³ or less. In this specification, the 15 ° C. density is a value measured in accordance with JIS K2249: 2011.

  The content of the base oil composition based on the total amount is preferably 60% by mass or more, more preferably from the viewpoint of having a more appropriate viscosity as the lubricating oil composition and improving wear resistance and oxidation stability. It is 70 mass% or more, More preferably, it is 85 mass% or more. Further, the upper limit is preferably 99.95% by mass or less, more preferably 99.9% by mass or less, and further preferably 99.5% by mass or less.

(Other additives)
The lubricating oil composition of the present embodiment contains the above base oil and phosphorus-containing compound, and may consist of the base oil and phosphorus-containing compound. In addition to the base oil and phosphorus-containing compound, For example, it may contain other additives such as a viscosity index improver, a dispersant, an antioxidant, an extreme pressure agent, a metal deactivator, an antifoaming agent, a friction reducing agent, and an oily agent. These other additives can be used alone or in combination of two or more.
The total content of other additives may be appropriately determined as desired, and is not particularly limited. However, in consideration of the effect of adding other additives, preferably 0.1% by mass or more based on the total amount of the composition. The upper limit is preferably 20% by mass or less, more preferably 15% by mass or less, and still more preferably 10% by mass or less.

  As the viscosity index improver, for example, a non-dispersion having a mass average molecular weight (Mw) of preferably 500 to 1,000,000, more preferably 5,000 to 800,000, still more preferably 10,000 to 700,000. Type polymethacrylate, polymethacrylate such as dispersed polymethacrylate; the mass average molecular weight (Mw) is preferably 800 to 300,000, more preferably 10,000 to 200,000, still more preferably 20,000 to 150,000. Such as olefin copolymer (for example, ethylene-propylene copolymer), dispersed olefin copolymer, styrene copolymer (for example, styrene-diene copolymer, styrene-isoprene copolymer), etc. Polymer; and the like.

  Examples of the dispersant include monovalent or divalent compounds represented by boron-free succinimides, boron-containing succinimides, benzylamines, boron-containing benzylamines, succinic esters, fatty acids or succinic acid. Examples include ashless dispersants such as carboxylic acid amides.

  Examples of the antioxidant include amine-based antioxidants such as diphenylamine-based antioxidants and naphthylamine-based antioxidants; monophenol-based antioxidants, diphenol-based antioxidants, hindered phenol-based antioxidants, etc. Phenolic antioxidants; molybdenum trioxides and / or molybdenum antioxidants such as molybdenum amine complexes formed by reacting molybdic acid with amine compounds; and the like.

  As extreme pressure agents, sulfur-based extreme pressure agents such as sulfurized fats and oils, sulfurized fatty acids, sulfurized esters, sulfurized olefins, dihydrocarbyl polysulfides, thiadiazole compounds, alkylthiocarbamoyl compounds, thiocarbamate compounds; zinc dialkylthiocarbamates (Zn-DTC) Sulfur-nitrogen extreme pressure agents such as molybdenum dialkylthiocarbamate (Mo-DTC); sulfur-phosphorus extreme pressure agents such as zinc dialkyldithiophosphate (Zn-DTP) and molybdenum dialkyldithiophosphate (Mo-DTP); Etc.

  Examples of the metal deactivator include benzotriazole, tolyltriazole, thiadiazole, and imidazole compounds. Examples of the antifoaming agent include silicone antifoaming agents such as silicone oil and fluorosilicone oil, Ether-based antifoaming agents such as fluoroalkyl ethers can be mentioned, and examples of friction reducing agents include aliphatic alcohols, fatty acids, fatty acid esters, aliphatic amines, aliphatic amine salts, aliphatic amides, etc., and oily agents Examples thereof include glycerol esters such as glycerol monooleate and glycerol dioleate.

(Various physical properties of lubricating oil composition)
Kinematic viscosity at 40 ° C. of the lubricating oil composition of the present embodiment, from the viewpoint of anti-seizing and low temperature fluidity of securing at high temperatures, preferably 3.0 mm 2 / ^s or more, more preferably 4.0 mm ² / s or more, more preferably at 5.0 mm ² / s or more, upper limit is preferably 30.0 mm ² / s or less, more preferably 20.0 mm ² / s or less, more preferably 10.0 mm ² / s or less is there. From the same viewpoint, the kinematic viscosity at 100 ° C. of the lubricating oil composition of the present embodiment is preferably 1.0 mm ² / s or more, more preferably 1.5 mm ² / s or more, and further preferably 2.0 mm. ^The upper limit is preferably 15.0 mm ² / s or less, more preferably 10.0 mm ² / s or less, and still more preferably 5.0 mm ² / s or less. Further, the viscosity index of the lubricating oil composition of the present embodiment is preferably 70 or more, more preferably 71 or more, and further preferably 72 or more.

  The wear scar width of the lubricating oil composition of this embodiment is preferably 0.55 mm or less, more preferably 0.50 mm or less, and even more preferably 0.40 mm or less. Moreover, it is preferable that no galling mark is generated. Here, the wear scar width and the galling scar are measured by the method described in the examples.

Further, for the oxidation stability of the lubricating oil composition of the present embodiment, the smaller the copper elution amount, the more preferable. Specifically, 10.0 mass ppm or less is preferable, and 8.0 mass ppm or less is more preferable. 3.0 mass ppm or less is more preferable. The smaller the iron elution amount, the better. Specifically, 5.0 mass ppm or less is preferred, 3.0 mass ppm or less is more preferred, and 1.0 mass ppm or less is even more preferred.
The lacquer degree is preferably 1 or less.
The smaller the insoluble content of n-pentane, the better. More specifically, it is preferably less than 0.02% by mass, more preferably 0.01% by mass or less, and still more preferably 0.005% by mass or less.
The smaller the Millipore value, the better. Specifically, it is preferably less than 5.0 mg / 100 ml, more preferably 3.0 mg / 100 ml or less, and even more preferably 2.0 mg / 100 ml or less.
The rate of change in kinematic viscosity at 40 ° C. is preferably as small as possible. Specifically, it is preferably less than ± 1.0%, more preferably ± 0.8% or less, and even more preferably ± 0.6% or less.
The copper elution amount, iron elution amount, lacquer degree, insoluble content of n-pentane, millipore value, and 40 ° C. kinematic viscosity change rate are determined by the method described in the examples.

(Use of lubricating oil composition)
Since the lubricating oil composition of the present embodiment is excellent in wear resistance and oxidation stability, for example, for drive system equipment such as a shock absorber, a transmission, and a power steering, for an engine, for hydraulic operation, for turbine It is suitably used for various devices and parts such as compressors, machine tools, cuttings, gears, fluid bearings, and rolling bearings. Considering the characteristics of excellent wear resistance and oxidation stability, it is preferably used for drive system equipment, and used for shock absorbers, especially automobile shock absorbers such as automobiles and motorcycles, especially automobile shock absorbers. It is preferred that
Also, from the viewpoint of effectively utilizing excellent wear resistance, the above equipment is suitable for equipment provided with parts using polytetrafluoroethylene (PTFE) material mixed with reinforcing materials such as glass fiber, graphite, and carbon fiber. For example, in equipment using a sliding bearing coated with PTFE on a bronze sintered material, a piston ring made of PTFE, etc., lubrication between the piston rod and bushing and between the inner tube and piston ring is required. It is suitably used for a drive system device, preferably a shock absorber, particularly a shock absorber for automobiles such as a four-wheeled vehicle and a two-wheeled vehicle, particularly a shock absorber for a four-wheeled vehicle.

[Method for producing lubricating oil composition]
The manufacturing method of the lubricating oil composition of this embodiment is characterized by blending a base oil and a phosphorus-containing compound represented by the following general formula (1).

In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ is 1 Or the integer of 2 is shown.

  In the manufacturing method of the lubricating oil composition of the present embodiment, the base oil and the phosphorus-containing compound are the same as those described as being included in the lubricating oil composition of the present embodiment, and the content thereof is It is the same as what was demonstrated as content in the lubricating oil composition of a form. In addition, in the method for producing the lubricating oil composition of the present embodiment, components other than the base oil and the phosphorus-containing compound, for example, other additives described as components that can be included in the lubricating oil composition of the present embodiment may be blended. .

  In producing the lubricating oil composition, the blending order of the base oil and the phosphorus-containing compound is not particularly limited, and may be blended in any order. Further, when other additives are blended, the blending order is not particularly limited. For example, various additives used as other additives may be blended sequentially into a blend of base oil and phosphorus-containing compound. .

[Lubrication method of drive system equipment]
The lubrication method of the drive system device of the present embodiment is characterized by using the lubricating oil composition of the present embodiment.
Since the lubricating oil composition of the present embodiment described above is excellent in wear resistance and oxidation stability, the lubricating method of the present embodiment is applied to drive system equipment such as a shock absorber, a transmission, and a power steering, particularly a buffer. It can be suitably used for lubricating a shock absorber for automobiles such as automobiles, especially automobiles such as automobiles and motorcycles, especially automobile automobile shock absorbers. These drive system devices are usually parts that use polytetrafluoroethylene (PTFE) material mixed with reinforcing materials such as glass fiber, graphite, and carbon fiber, such as sliding bearings coated with PTFE on bronze sintered material, PTFE material Parts such as made piston rings are provided, and lubrication in these parts, more specifically, between the piston rod and the bush and between the inner tube and the piston ring is required. By using the lubricating oil composition of this embodiment, regardless of the material related to the sliding part of these parts, that is, the material related to the sliding part is not limited to metal-metal, even if PTFE material-metal, Generation | occurrence | production of a wear trace and a galling trace can be suppressed and durability of a drive system apparatus can be improved. Therefore, the drive system lubrication method of the present embodiment is particularly preferably employed in drive system equipment including parts using polytetrafluoroethylene among the drive system equipment.

[Drive system equipment]
The drive system device of the present embodiment uses the lubricating oil composition of the present embodiment. As the drive system device of the present embodiment, a drive system device such as a shock absorber, a transmission, and a power steering, particularly a shock absorber, particularly a shock absorber for automobiles such as four-wheeled vehicles and two-wheeled vehicles, particularly a shock absorber for four-wheeled vehicles is suitable. It is mentioned in.
The lubricating oil composition of the present embodiment is not limited to metal-metal as the material related to the sliding part, and even if it is a PTFE material-metal, excellent wear resistance can suppress the generation of wear marks and galling marks. As a result, the drive system device of this embodiment has high durability. Considering the characteristics of the lubricating oil composition used in the drive system device of the present embodiment, the drive system device of the present embodiment includes polytetrafluoroethylene (PTFE) in which a reinforcing material such as glass fiber, graphite, and carbon fiber is blended. It is preferable to include parts such as a sliding bearing coated with PTFE on a bronze sintered material and a piston ring made of PTFE material.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not restrict | limited at all by these examples.

The properties and performance of the base oil and lubricating oil composition were measured and evaluated by the following methods.
(1) Kinematic viscosity Based on JISK2283: 2000, the kinematic viscosity in 40 degreeC and 100 degreeC was measured.
(2) Viscosity index (VI)
It measured based on JISK2283: 2000.
(3) Density at 15 ° C. Measured according to JIS K2249: 2011.

(4) Evaluation of wear resistance (wear scar width)
With respect to the lubricating oil compositions of Examples and Comparative Examples obtained by mixing the components shown in Table 1, a ball-on-disk type reciprocating friction tester (Bowden-Leven type) was used, and the load was 29.4 N. A friction test was conducted at a temperature of 100 ° C., a sliding speed of 50 mm / s, a stroke of 10 mm, and a time of 30 minutes, and the wear scar width on the disk was measured. The balls are glass spheres (diameter 12 mm), and the disks are made of material SPCC-SB. It can be said that the smaller the wear scar width, the better the wear resistance.
(5) Evaluation of wear resistance (galling marks)
For the lubricating oil compositions of the examples and comparative examples obtained by mixing the components shown in Table 1, the same friction test as in the above (4) evaluation of wear resistance was performed, and the end of reciprocation on the disk The presence or absence of galling marks in the part was visually confirmed. If there is no galling mark, it can be said that the wear resistance is excellent.

(6) Evaluation of oxidation stability About the lubricating oil composition of each Example obtained by mixing each component of Table 1, and the comparative example, it obtained by conducting the following tests (a)-(e). , Copper elution amount (mass ppm) A, iron elution amount (mass ppm) B, lacquer color score C, n-pentane insoluble matter (mass%) D, millipore value (mg / 100 ml) E and 40 ° C kinematic viscosity change rate (%) as F, A is 10.0 mass ppm or less, B is 5.0 mass ppm or less, C is 1 or less, and D is less than 0.02 mass%. , E was less than 5.0 mg / 100 ml, and F was less than ± 1.0%. The number of passes for the six items A to F was evaluated according to the following criteria to obtain a comprehensive evaluation of oxidation stability. If it is evaluation 1, it will be a pass.
1: All six items of A to F passed.
2: Passed 4 to 5 items of A to F.
3: Passed 3 or less items of A to F.

(A) Measurement of elution amounts of copper and iron The lubricating oil compositions of Examples and Comparative Examples obtained by mixing the components shown in Table 1 were subjected to an ISOT test in accordance with JIS K2514-1: 2013. Then, a plate-like iron catalyst and a copper catalyst, which are catalysts, were added to the lubricating oil composition to degrade the sample at a test temperature of 120 ° C., a test time of 24 hours, and a stirring speed of 1300 rpm. ppm) and the elution amount (mass ppm) of iron. The elution amount of copper was A, and the elution amount of iron was B.
(B) Measurement of Lacquer Degree Oxidation tests based on JIS K2514-1: 2013 are conducted on the lubricating oil compositions of Examples and Comparative Examples obtained by mixing the components shown in Table 1, and an evaluation sample is obtained. The degree of lacquer was determined by comparing with (color scale) and designated as C.
(C) Measurement of n-pentane insoluble matter Using the lubricating oil compositions of Examples and Comparative Examples obtained by mixing the components shown in Table 1 as sample oils, (a) Elution of copper and iron After performing the same test as the ISOT test performed by measuring the amount, n-pentane insoluble matter (Method A) (mass%) was measured. n-pentane insoluble matter (Method A) (mass%) was defined as D.
(D) Measurement of Millipore Value Lubricating oil compositions of Examples and Comparative Examples obtained by mixing the components shown in Table 1 were used as sample oil, and 300 ml of sample oil was placed in a cylinder container. A plate-like iron catalyst and a copper catalyst as catalysts were added, and an Indiana oxidation test was performed by heating at 150 ° C. for 24 hours while blowing air at 10 L / h through an air blowing tube. Next, in accordance with SAE-ARP-785-63: 1996, the precipitate in 300 ml of sample oil after the Indiana oxidation test was collected by filtration (average pore size: 0.8 μm), and the mass was measured in millipore value (mg / 100 ml). ). E. Millipore value (mg / 100 ml).
(E) Measurement of Kinematic Viscosity Change Rate at 40 ° C. The lubricating oil compositions of Examples and Comparative Examples obtained by mixing the components shown in Table 1 were used as sample oils in accordance with JASO M347-95. The sonicated product obtained by irradiating the sonic wave for 60 minutes and the untreated sample oil were measured for 40 ° C. kinematic viscosity according to JIS K2283: 2000, and the treated product 40 ° C. kinematic viscosity was v ₁ , The rate of decrease ((v ₀ −v ₁ ) / v ₀ × 100) when the 40 ° C. kinematic viscosity of the untreated product was v ₀ was defined as 40 ° C. kinematic viscosity change rate.

(Preparation of lubricating oil compositions of Examples 1 and 2 and Comparative Examples 1 to 12)
A lubricating oil composition was prepared by blending according to the blending formulation shown in Table 1 below. Table 1 shows the evaluation results of the properties and performances measured by the above methods for the obtained lubricating oil compositions.

The details of each component shown in Table 1 used in this example are as follows.
Base oil: paraffinic mineral oil (40 ° C. kinematic viscosity: 8.386 mm ² / s, 100 ° C. kinematic viscosity: 2.300 mm ² / s, viscosity index: 78, 15 ° C. density: 0.8682 g / cm ³ )
Phosphorus-containing compound 1: Phosphonic acid ester (hydroxymethylphosphonic acid di--) of general formula (1): R ¹¹ : 2-ethylhexyl group, X ¹¹ : -R ¹² OH (R ¹² : methylene group), n ₁₁ : 2 2-ethylhexyl)
Phosphorus-containing compound 2: In general formula (1), R ¹¹ : ethyl group, X ¹¹ : -OR ¹³ (R ¹³ : oleyl group), n ₁₁ : 2 phosphate ester (diethyloleyl phosphate)
Additive 1: Di-t-butylparacresol (antioxidant)
Additive 2: Sesquioleyl acid phosphate (mixture of monooleyl acid phosphate and dioleyl acid phosphate)
Additive 3: Amine salt of acidic phosphate (mixture of amine salt of monomethyl acid phosphate and monoethyl acid phosphate monoethyl)
Additive 4: Zinc dialkyldithiophosphate (containing primary propyl group, butyl group and hexyl group)
Additive 5: Distearyl pentaerythritol diphosphite Additive 6: Zinc dialkyldithiophosphate (containing secondary propyl group and hexyl group)
Additive 7: 3- (Di-isobutoxy-thiophosphorylsulfanyl) -2-methyl-propionic acid Additive 8: 2,5-bis [(1,1,3,3-tetramethylbutyl) dithio]- 1,3,4-thiadiazole / additive 9: dilauryl hydrogen phosphite / additive 10: sesquilauryl hydrogen phosphite (mixture of monolauryl hydrogen phosphite and dilauryl hydrogen phosphite, acid value: 60mgKOH / g)
Additive 11: Sesquilauryl hydrogen phosphite (mixture of monolauryl hydrogen phosphite and dilauryl hydrogen phosphite, acid value: 70 mg KOH / g)
Additive 12: Sesquilauryl hydrogen phosphite (mixture of monolauryl hydrogen phosphite and dilauryl hydrogen phosphite, acid value: 80 mgKOH / g)

  The lubricating oil compositions of Examples 1 and 2 have a friction mark width of 0.55 mm or less, no galling mark is generated, copper elution amount is 10.0 mass ppm or less, and iron elution amount is 5.0. Mass ppm or less, lacquer degree 1 or less, n-pentane insoluble content is less than 0.02 mass%, millipore value is less than 5.0 mg / 100 ml, and 40 ° C. kinematic viscosity change rate is less than ± 1.0%. From this, it was confirmed that the lubricating oil composition of the present embodiment has excellent wear resistance and oxidation stability. Further, in comparison with Examples 1 and 2, when the phosphorus-containing compound is a phosphonic acid ester having an organic group containing a hydroxyl group, more excellent wear resistance is obtained, and when the phosphorus-containing compound is a phosphoric acid ester, It can be seen that excellent oxidation stability is obtained.

On the other hand, the lubricating oil compositions of Comparative Examples 1 to 12 that do not contain the phosphorus-containing compound represented by the general formula (1) cannot satisfy any performance of wear resistance and oxidation degradation index, and are excellent. Further, it could not be said to have high wear resistance and oxidation stability.
Further, for example, the lubricating oil compositions of Comparative Examples 4 and 6 contain zinc dialkyldithiophosphate (ZnDTP), which has been conventionally used as an antiwear agent, both of which show galling marks and have excellent wear resistance. It could not be said to have a property. The lubricating oil composition of Comparative Example 2 contains oleyl acid phosphate, but is different from the phosphorus-containing compound represented by the general formula (1) in that the hydroxyl group is linked to the phosphorus atom, and has excellent oxidation stability. It could not be said to have a property. The lubricating oil compositions of Comparative Examples 9 to 12 contain lauryl hydrogen phosphite, but differ from the phosphorus-containing compound represented by the general formula (1) in that a hydrogen atom is connected to a phosphorus atom. It cannot be said that it has excellent oxidation stability.
Further, from the results of Comparative Examples 4, 5, and 6, it can be seen that in wear resistance, if one of the wear mark width and the galling mark is satisfied, the other is not satisfied.

  As described above, from the results of Examples and Comparative Examples, the lubricating oil composition of the present embodiment exhibits excellent performance with respect to lubrication having different properties in terms of wear resistance by containing a specific phosphorus-containing compound. It was confirmed that it not only obtained but also excellent in oxidation stability.

Claims (15)

A lubricating oil composition comprising a base oil and a phosphorus-containing compound represented by the following general formula (1).

(In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ represents Indicates an integer of 1 or 2.) In the general formula (1), X ¹¹ represents —R ¹² OH or —OR ¹³ , R ¹² represents a divalent hydrocarbon group having 1 to 30 carbon atoms, and R ¹³ represents a monovalent carbon number of 1 The lubricating oil composition according to claim 1, which shows 30 or less hydrocarbon groups. In the general formula (1), R ¹¹ is a monovalent aliphatic hydrocarbon group having 3 to 20 carbon atoms, X ¹¹ is —R ¹² OH, and R ¹² is 2 having 1 to 12 carbon atoms. The lubricating oil composition according to claim 2, which is a valent aliphatic hydrocarbon group. The lubricating oil composition according to claim 3, wherein, in the general formula (1), R ¹¹ has more carbon atoms than R ¹² . In the general formula (1), R ¹¹ is an alkyl group having 4 to 16 carbon atoms, R ¹² is an alkylene group having 1 to 3 carbon atoms, and n ₁₁ is 2. 5 or The lubricating oil composition described. In the general formula (1), R ¹¹ is a monovalent aliphatic hydrocarbon group having 1 to 12 carbon atoms, X ¹¹ is —OR ¹³ , and R ¹³ is a monovalent carbon having 4 to 24 carbon atoms. The lubricating oil composition according to claim 2, which is an aliphatic hydrocarbon group. The lubricating oil composition according to claim 6, wherein in the general formula (1), n ₁₁ is 2, and R ¹³ has more carbon atoms than R ¹¹ . The lubricating oil composition according to claim 6 or 7, wherein, in the general formula (1), R ¹¹ is an alkyl group having 1 to 6 carbon atoms, and R ¹³ is an alkenyl group having 7 to 20 carbon atoms.   The lubricating oil composition according to any one of claims 1 to 8, wherein a content of the phosphorus-containing compound based on the total amount of the composition is 0.05% by mass or more and 3.0% by mass or less.   The lubricating oil composition according to any one of claims 1 to 9, which is used for drive system equipment. The manufacturing method of the lubricating oil composition which mix | blends base oil and the phosphorus containing compound represented by following General formula (1).

(In the general formula (1), R ¹¹ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms, X ¹¹ represents an oxygen atom, an organic group having 1 to 30 carbon atoms, and n ₁₁ represents Indicates an integer of 1 or 2.)   A method for lubricating a drive train using the lubricating oil composition according to any one of claims 1 to 10.   The drive system apparatus using the lubricating oil composition of any one of Claims 1-10.   The drive system apparatus of Claim 13 provided with the components in which the polytetrafluoroethylene was used.   The drive system apparatus according to claim 13 or 14, which is a shock absorber.