JP7360239B2 - Lubricating oil composition, method for producing lubricating oil composition, lubrication method, and industrial machinery - Google Patents

Description

The present invention relates to a lubricating oil composition, a method for producing a lubricating oil composition, a lubrication method, and an industrial machine.
Regarding.

For example, industrial machinery such as agricultural machinery, construction machinery, and transportation machinery is usually equipped with transmissions (gears), hydraulic operating parts, etc., and the performance generally required of lubricating oil compositions used in industrial machinery is , prevention of seizure and wear of transmissions, and viscosity characteristics for maintaining hydraulic output.

Among industrial machinery, for example, agricultural machinery such as tractors, rice transplanters, binders, and combines; construction machinery such as hydraulic excavators, crane trucks, and bulldozers; and transportation machinery such as dump trucks, forklifts, shovel loaders, and rough terrain vehicles. , and further equipped with wet brakes, and the transmissions (gears), hydraulic operating parts, and wet brakes of these machines are generally lubricated with the same lubricating oil composition. For example, lubricating oil compositions containing one or more selected from zinc dialkyldithiophosphate, basic calcium sulfonate, and basic calcium phenate have been proposed as lubricating oil compositions for use in agricultural machinery (for example, patent (See Reference 1).

Japanese Patent Application Publication No. 2009-144097

By the way, a problem specific to wet brakes is brake squeal caused by vibrations caused by stick-slip, the repetition of adhesion and slippage between friction surfaces. Therefore, lubricating oil compositions used in industrial machines equipped with wet brakes are particularly required to have the ability to prevent brake squeal (hereinafter referred to as "brake squeal prevention performance").
However, the lubricating oil composition disclosed in Patent Document 1 cannot satisfy the brake squeal prevention performance, and there is a need for technological development of a lubricating oil composition that satisfies the brake squeal prevention performance.

The present invention was made in view of the above circumstances, and provides a lubricating oil composition having excellent brake squeal prevention performance, a method for producing the lubricating oil composition, and a lubrication method and industrial machine using the lubricating oil composition. The purpose is to

As a result of extensive research, the present inventors have discovered that the above-mentioned problems can be solved by the following invention. That is, the present invention provides a lubricating oil composition having the following configuration, a method for producing the lubricating oil composition, and a lubrication method and industrial machine using the lubricating oil composition.

1. A lubricating oil composition containing a base oil (A), a hydroxyl group-containing amine compound (B) represented by the following general formula (1), and an amine compound (C) represented by the following general formula (2). .

(In general formula (1), R ¹¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ¹² and R ¹³ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms.)

(In general formula (2), R ²¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ²² and R ²³ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms. , at least one of R ²² and R ²³ is a hydrogen atom.)

2. The lubricating oil composition as described in 1 above, further comprising an amide compound (D) represented by the following general formula (3).

(In general formula (3), R ³¹ is an organic group having 1 to 30 carbon atoms, and R ³² and R ³³ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms.)

3. A lubrication process comprising the step of blending a base oil (A), a hydroxyl group-containing amine compound (B) represented by the above general formula (1), and an amine compound (C) represented by the above general formula (2). Method for producing an oil composition.
4. 3. The method for producing a lubricating oil composition according to 3 above, wherein in the step, an amide compound (D) represented by the following general formula (3) is further blended.
5. A lubrication method using the lubricating oil composition according to 1 or 2 above.
6. An industrial machine using the lubricating oil composition according to 1 or 2 above, and comprising a transmission, a hydraulic operating part, and a wet brake.

According to the present invention, it is possible to provide a lubricating oil composition having excellent brake squeal prevention performance, a method for producing the lubricating oil composition, and a lubrication method and industrial machine using the lubricating oil composition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention (hereinafter sometimes simply referred to as "this embodiment") will be described below. In addition, in this specification, the numerical values related to "more than", "less than", and "~" regarding the description of numerical ranges are numerical values that can be arbitrarily combined, and the numerical values in the examples can be used as the upper limit value or the lower limit value. It is a numerical value.

[Lubricating oil composition]
The lubricating oil composition of the present embodiment includes a base oil (A), a hydroxyl group-containing amine compound (B) represented by the following general formula (1), and an amine compound (C ). Each component will be explained below.

(In general formula (1), R ¹¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ¹² and R ¹³ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms.)

(In general formula (2), R ²¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ²² and R ²³ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms. , at least one of R ²² and R ²³ is a hydrogen atom.)

(Base oil (A))
The base oil (A) used in the lubricating oil composition of this embodiment may be mineral oil or synthetic oil.
Mineral oils include atmospheric residual oil obtained by atmospheric distillation of paraffinic, naphthenic, and intermediate crude oils; distillate oil obtained by vacuum distillation of the atmospheric residual oil; Mineral oil refined by subjecting oil to one or more of the following treatments: solvent deasphalting, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, etc., such as light neutral oil, medium neutral oil, etc. Oil, heavy neutral oil, bright stock, and mineral oil obtained by isomerizing wax (GTL wax) produced by the Fischer-Tropsch method or the like.

In addition, the mineral oil may be classified into Group 1, 2, or 3 in the API (American Petroleum Institute) base oil category, but it can improve brake squeal prevention performance and suppress sludge generation. Those classified into Groups 2 and 3 are preferable from the viewpoint of improving the performance of preventing seizure and wear of the transmission, the viscosity characteristics, the stability against oxidative deterioration, etc.

Examples of synthetic oils include polybutene, polyα-olefins such as ethylene-α-olefin copolymers, α-olefin homopolymers or copolymers; various esters such as polyol esters, dibasic acid esters, and phosphoric acid esters. ; various ethers such as polyphenyl ether; polyglycols; alkylbenzenes; alkylnaphthalenes and the like.

There is no particular restriction on the viscosity of the base oil (A), but from the viewpoint of improving the performance of preventing brake squeal, the performance of preventing seizure and wear of transmissions, the viscosity characteristics, and the stability against oxidative deterioration, etc. The kinematic viscosity at °C is preferably 2 mm ² /s or more, more preferably 3 mm ² /s or more, even more preferably 4 mm ² /s or more, and the upper limit is preferably 25 mm ² /s or less, more preferably 20 mm ^{2 /} s. s or less, more preferably 15 mm ² /s or less.
In addition, the viscosity index of the base oil (A) is preferably 80 or more, from the viewpoint of improving not only brake squeal prevention performance but also transmission seizure and wear prevention performance, viscosity characteristics, and stability against oxidative deterioration. , more preferably 90 or more, and even more preferably 95 or more. Here, the kinematic viscosity and the viscosity index are values measured using a glass capillary viscometer in accordance with JIS K 2283:2000.

As the base oil (A), mineral oils may be used alone or in combination of two or more types, synthetic oils may be used in one type, or two or more types may be used in combination. Furthermore, a combination of one or more mineral oils and one or more synthetic oils may be used as a mixed oil.
Further, the content of the base oil (A) based on the total amount of the lubricating oil composition is usually 50% by mass or more, preferably 60 to 97% by mass, more preferably 70 to 95% by mass, and even more preferably 80% by mass. ~95% by mass.

(Hydroxy group-containing amine compound (B))
The lubricating oil composition of this embodiment contains a hydroxyl group-containing amine compound (B) represented by the following general formula (1). The hydroxyl group-containing amine compound (B) has excellent solubility in base oil, and interacts with the amine compound (C) described below, more preferably the amide compound (D), to form the lubricating oil composition of the present embodiment. , which provides the general performance required for industrial machinery, such as the ability to prevent seizure and wear of transmissions, viscosity characteristics, stability against oxidative deterioration, etc., and also provides excellent brake squeal prevention performance. It is. Therefore, if the lubricating oil composition of this embodiment does not contain the hydroxyl group-containing amine compound (B), no interaction with the amine compound (C) will be obtained, and it will not have excellent general performance required for industrial machinery. Brake squeal prevention performance cannot be obtained.

In the general formula (1), R ¹¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ¹² and R ¹³ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms. It is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and unless R ¹² and R ¹³ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms, it has excellent solubility in base oil as well as brake squeal prevention performance. , it is not possible to improve the performance of preventing seizure and wear of the transmission, the viscosity characteristics, the stability against oxidative deterioration, etc.

The aliphatic hydrocarbon group having 12 to 30 carbon atoms in ^R11 has excellent solubility in base oil, prevents seizure and wear of transmissions, has viscosity characteristics, and is stable against oxidative deterioration, etc., as well as brake squeal prevention performance. From the viewpoint of improving properties, for example, straight-chain or branched alkyl groups and alkenyl groups having 12 to 30 carbon atoms are preferably mentioned, and straight-chain or branched alkyl groups having 12 to 24 carbon atoms, Alkenyl groups are more preferred, and linear or branched alkyl groups and alkenyl groups having 16 to 20 carbon atoms are preferred.

For example, as a linear or branched alkyl group having 12 to 30 carbon atoms, various dodecyl groups (hereinafter referred to as ), various tridecyl groups, various tetradecyl groups, various pentadecyl groups, various hexadecyl groups, various heptadecyl groups, various octadecyl groups. , various nonadecyl groups, various icosyl groups, various henicosyl groups, various docosyl groups, various tricosyl groups, various tetracosyl groups, various pentacosyl groups, various hexacosyl groups, various heptacyl groups, various octacosyl groups, various nonacosyl groups, and various triacontyl groups. Can be mentioned.

In addition, as the linear or branched alkenyl group having 12 to 30 carbon atoms, various dodecenyl groups, various tridecenyl groups, various tetradecenyl groups, various pentadecenyl groups, various hexadecenyl groups, various heptadecenyl groups, various octadecenyl groups, various Nonadecenyl groups, various icosenyl groups, various henicosenyl groups, various docosenyl groups, various tricosenyl groups, various tetracosenyl groups, various pentacosenyl groups, various hexacosenyl groups, various heptacocenyl groups, various octacosenyl groups, various nonacosenyl groups, and various triacontinyl groups. Can be mentioned.

In particular, considering the improvement of brake squeal prevention performance, various hexadecyl groups, various heptadecyl groups, various octadecyl groups with 16 to 18 carbon atoms, various hexadecenyl groups, various heptadecenyl groups, various octadecenyl groups with 16 to 18 carbon atoms Alkenyl groups having 16 to 18 carbon atoms such as various hexadecenyl groups, various heptadecenyl groups, and various octadecenyl groups are more preferable, various octadecenyl groups are still more preferable, and n-octadecenyl groups are particularly preferable, and among them, oleyl groups are preferable. Note that R ¹¹ above may be partially substituted with a hydroxyl group, a halogen atom, or the like.

The aliphatic hydrocarbon group having 1 to 5 carbon atoms in R ¹² and R ¹³ has properties such as brake squeal prevention performance, solubility in base oil, transmission seizure and wear prevention performance, viscosity characteristics, oxidative deterioration, etc. From the viewpoint of improving stability, preferred examples include linear or branched alkylene groups having 1 to 5 carbon atoms, and linear or branched alkenylene groups having 2 to 5 carbon atoms. More preferred examples include linear or branched alkylene groups having 1 to 3 carbon atoms, linear or branched alkenylene groups having 2 to 3 carbon atoms, and linear alkylene groups having 1 to 2 carbon atoms; More preferred is a linear alkenylene group having 2 carbon atoms.

Examples of linear or branched alkylene groups having 1 to 5 carbon atoms include methylene groups, ethylene groups, various propylene groups, various butylene groups, and various pentylene groups. Further, examples of the linear or branched alkenylene group having 2 to 5 carbon atoms include a vinylene group, various propenylene groups, various butenylene groups, and various pentenylene groups.
Among these, an alkylene group is preferred, and an alkylene group having 2 carbon atoms, ie, an ethylene group, is particularly preferred in view of improving brake squeal prevention performance.
R ¹² and R ¹³ may be the same or different, and are preferably the same from the viewpoint of improving brake squeal prevention performance.

A particularly preferred specific compound of the hydroxyl group-containing amine compound (B) represented by the general formula (1) is stearyldiethanolamine (in the general formula (1), R ¹¹ is an octadecyl group, R ¹² and R ¹³ are ), oleyldiethanolamine (in general formula (1), R ¹¹ is an octadecenyl group, and R ¹² and R ¹³ are ethylene groups).

(Amine compound (C))
The lubricating oil composition of this embodiment contains an amine compound (C) represented by the following general formula (2). The amine compound (C) has excellent solubility in base oil, and due to the interaction with the hydroxyl group-containing amine compound (B), the lubricating oil composition of this embodiment has the general properties required for industrial machinery. It imparts performance, that is, performance in preventing seizure and wear of the transmission, viscosity characteristics, stability against oxidative deterioration, etc., and provides excellent brake squeal prevention performance. Therefore, if the lubricating oil composition of this embodiment does not contain the amine compound (C), no interaction with the hydroxyl group-containing amine compound (B) will be obtained, and it will not have excellent general performance required for industrial machinery. Brake squeal prevention performance cannot be obtained.
The lubricating oil composition of the present embodiment preferably further contains an amide compound (D) together with the amine compound (C), from the viewpoint of improving the effect of the above interaction, that is, the amine compound (C) and the amide compound ( D) is preferably used in combination. Here, the amine compound (C) may be used alone or in combination, and the same applies to the amide compound (D).
First, the amine compound (C) will be explained.

The amine compound (C) used in this embodiment is a compound represented by the following general formula (2).

In the general formula (2), R ²¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, R ²² and R ²³ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms, At least one of R ²² and R ²³ is a hydrogen atom. R ²¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, R ²² and R ²³ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms, and at least R ²² and R ²³ are On the other hand, if it is not a hydrogen atom, it will not be possible to improve brake squeal prevention performance, solubility in base oil, excellent transmission seizure and wear prevention performance, viscosity characteristics, stability against oxidative deterioration, etc.

Regarding the amine compound (C) represented by the general formula (2), the aliphatic hydrocarbon group having 12 to 30 carbon atoms in R ²¹ has excellent solubility in base oil, excellent solubility in base oil, and excellent performance in preventing brake squeal. From the viewpoint of improving seizure and wear prevention performance, viscosity characteristics, stability against oxidative deterioration, etc., for example, those exemplified as the aliphatic hydrocarbon group having 12 to 30 carbon atoms for R ¹¹ above are preferably mentioned, and specific Specifically, an alkyl group and an alkenyl group are preferable. The number of carbon atoms in R ²¹ is preferably 12 to 30, more preferably 12 to 24, and even more preferably 16 to 20, which is the same as R ¹¹ above.
In particular, considering the improvement of brake squeal prevention performance, ^R21 may include various hexadecyl groups, various heptadecyl groups, various octadecyl groups having 16 to 18 carbon atoms, various hexadecenyl groups, various heptadecenyl groups, and various octadecenyl groups. Alkenyl groups having 16 to 18 carbon atoms are preferred, alkenyl groups having 16 to 18 carbon atoms such as various hexadecenyl groups, various heptadecenyl groups, and various octadecenyl groups are more preferred, various octadecenyl groups are still more preferred, and n-octadecenyl groups are particularly preferred. An oleyl group is preferred.

^R22 and ^R23 are hydrogen atoms, or at least one of them is a hydrogen atom, and in addition to brake squeal prevention performance, excellent solubility in base oil, transmission seizure and wear prevention performance, viscosity characteristics, stability against oxidative deterioration, etc. From the viewpoint of improving performance, particularly in improving brake squeal prevention performance, it is preferable that R ²² and R ²³ are both hydrogen atoms.

As mentioned above, R ²² and R ²³ are both preferably hydrogen atoms, but may also be aliphatic hydrocarbon groups having 1 to 5 carbon atoms. Examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms include a linear or branched alkyl group having 1 to 5 carbon atoms, and a linear or branched alkenyl group having 2 to 5 carbon atoms. Preferred examples include straight chain or branched alkyl groups having 1 to 3 carbon atoms, straight chain or branched alkenyl groups having 2 to 3 carbon atoms, and straight chain or branched alkenyl groups having 1 to 2 carbon atoms. More preferred are a chain alkyl group and a straight chain alkenyl group having 2 carbon atoms. Even if either R ²² or R ²³ is an aliphatic hydrocarbon group having the above-mentioned number of carbon atoms, it will have brake squeal prevention performance, solubility in base oil, and excellent transmission seizure and wear prevention performance. Viscosity characteristics and stability against oxidative deterioration are improved.

Examples of linear or branched alkyl groups having 1 to 5 carbon atoms include methyl groups, ethyl groups, various propyl groups, various butyl groups, and various pentyl groups. Further, examples of the linear or branched alkenyl group having 2 to 5 carbon atoms include a vinyl group, various propenyl groups, various butenyl groups, and various pentenyl groups. In particular, in consideration of brake squeal prevention performance, an alkyl group is preferable, and an alkyl group having 1 carbon number, ie, a methyl group, is particularly preferable. Further, the aliphatic hydrocarbon groups of R ²¹ , R ²² and R ²³ described above may be partially substituted with a hydroxyl group, a halogen atom, or the like.

As the amine compound (C) represented by the general formula (2), compounds in which R ²¹ is an alkyl group or alkenyl group having 12 to 30 carbon atoms, and R ²² and R ²³ are hydrogen atoms are preferred, and particularly preferred. Specific amine compounds (C) include monostearylamine (in general formula (2), R ²¹ is an octadecyl group, and R ²² and R ²³ are hydrogen atoms), monooleylamine (general formula (2) ), R ²¹ is an octadecenyl group, and R ²² and R ²³ are hydrogen atoms.

(Amide compound (D))
The lubricating oil composition of the present embodiment preferably further contains an amide compound (D) represented by the following general formula (3). Including the amide compound (D) improves brake squeal prevention performance, excellent solubility in base oil, transmission seizure and wear prevention performance, viscosity characteristics, and stability against oxidative deterioration.

In the general formula (3), R ³¹ is an organic group having 1 to 30 carbon atoms, and R ³² and R ³³ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms.

Regarding the amide compound (D) represented by the general formula (3), examples of the organic group for R ³¹ include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a heterocyclic group, etc. From the viewpoint of improving brake squeal prevention performance, excellent solubility in base oil, transmission seizure and wear prevention performance, viscosity characteristics, stability against oxidative deterioration, etc., aliphatic hydrocarbon groups are preferred.

Examples of the aliphatic hydrocarbon group for R ³¹ include alkyl groups and alkenyl groups, and more specifically, the above-mentioned alkyl groups and alkenyl groups having 1 to 5 carbon atoms, and the above-mentioned alkyl groups and alkenyl groups having 12 to 30 carbon atoms. In addition to alkyl groups and alkenyl groups, examples include alkyl groups having 6 to 11 carbon atoms, that is, various hexyl groups, various heptyl groups, various octyl groups, various nonyl groups, various decyl groups, various undecyl groups, and corresponding alkenyl groups. It will be done. Further, these alkyl groups and alkenyl groups may be partially substituted with a hydroxyl group, a halogen atom, or the like.
When R ³¹ is an aliphatic hydrocarbon group, the number of carbon atoms is preferably 12 to 30, more preferably 12 to 24, and even more preferably 16 to 20, especially considering brake squeal prevention performance.

The alicyclic hydrocarbon group for ^R31 typically includes a cyclohexyl group, a dimethylcyclohexyl group, an ethylcyclohexyl group, a methylcyclohexylmethyl group, a cyclohexylethyl group, a propylcyclohexyl group, a butylcyclohexyl group, a heptylcyclohexyl group, and the like. Examples include a cycloalkyl group and a cycloalkenylene group corresponding to the cycloalkyl group.
When R ³¹ is an alicyclic hydrocarbon group, the number of carbon atoms is preferably 3 to 30, more preferably 4 to 24, and even more preferably 6 to 16, especially considering brake squeal prevention performance.

The aromatic hydrocarbon group for ^R31 is typically an aryl group such as a phenyl group, a naphthyl group, an anthracenyl group, a biphenyl group, or a terphenyl group, a methylphenyl group (tolyl group), a dimethylphenyl group, or a butylphenyl group. group, alkylaryl groups such as nonylphenyl group, dimethylnaphthyl group, arylalkyl groups such as phenylmethyl group, phenylethyl group, phenylpropyl group, methylbenzyl group, diphenylmethyl group, etc.; Representative examples thereof include pyridyl group, pyrazyl group, triazinyl group, furyl group, thienyl group, thiophenyl group, thiazolyl group, thiadiazolyl group, benzothiazolyl group, imidazolyl group, benzimidazolyl group, and the like.
When R ³¹ is an aromatic hydrocarbon group, the number of carbon atoms is preferably 6 to 30, more preferably 6 to 24, and even more preferably 6 to 12, especially considering brake squeal prevention performance.

These alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and heterocyclic groups may be substituted with alkyl groups, hydroxyl groups, alkoxy groups, halogen atoms, etc., and the alkyl groups contained in these groups The aliphatic hydrocarbon groups may be either linear or branched.

R ³² and R ³³ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, preferably at least one is a hydrogen atom, and more preferably both are hydrogen atoms. Since at least one of them is a hydrogen atom, the interaction between the hydroxyl group-containing amine compound (B) and the amine compound (C) is particularly promoted, which improves brake squeal prevention performance, solubility in base oil, and speed change. It is possible to improve machine seizure and wear prevention performance, viscosity characteristics, stability against oxidative deterioration, etc.

Furthermore, as the organic group having 1 to 30 carbon atoms for R ³² and R ³³ , those exemplified as the organic group having 1 to 30 carbon atoms for R ³¹ above are preferably used. The organic group having 1 to 30 carbon atoms in R ³² and R ³³ is preferably an aliphatic hydrocarbon, and preferably has 12 to 30 carbon atoms ^. is the same as

The amide compound (D) represented by the general formula (3) is particularly suitable for R ³¹ being an alkyl group or alkenyl group having 12 to 30 carbon atoms, and R ³² and R ³³ is a hydrogen atom, and a particularly preferred specific amide compound (D) is monostearylamide (in general formula (3), R ³¹ is an octadecyl group, R ³² and R ³³ are hydrogen atoms) ), monooleylamide (in general formula (3), R ³¹ is an octadecenyl group, and R ³² and R ³³ are hydrogen atoms).

(Content of each component)
The content of the hydroxyl group-containing amine compound (B) based on the total amount of the composition is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.15% by mass or more, and the upper limit is Preferably it is 1.0% by mass or less, more preferably 0.8% by mass or less, still more preferably 0.4% by mass or less. Further, the content of nitrogen atoms in the hydroxyl group-containing amine compound (B) based on the total amount of the composition is preferably 10 to 300 mass ppm, more preferably 20 to 250 mass ppm, and even more preferably 20 to 200 mass ppm. When the content of the hydroxyl group-containing amine compound (B) based on the total composition and the content of nitrogen atoms in the hydroxyl group-containing amine compound (B) based on the total composition are within the above ranges, brake squeal prevention performance and speed change It is possible to efficiently improve machine seizing and wear prevention performance, viscosity characteristics, stability against oxidative deterioration, etc.

The mass ratio of the hydroxyl group-containing amine compound (B) to the amine compound (C) (content of the hydroxyl group-containing amine compound (B)/content of the amine compound (C)) is preferably 0.10 or more, more preferably It is 0.50 or more, more preferably 1.00 or more, and the upper limit is preferably 10.00 or less, more preferably 8.00 or less, and still more preferably 5.00 or less. When the mass ratio of the hydroxyl group-containing amine compound (B) to the amine compound (C) is within the above range, the brake squeal prevention performance in particular can be efficiently improved due to the interaction of these components.

Furthermore, when containing an amide compound (D), the mass ratio of the hydroxyl group-containing amine compound (B) and the amide compound (D) (content of the hydroxyl group-containing amine compound (B)/content of the amide compound (D)) is , preferably 0.10 or more, more preferably 0.50 or more, still more preferably 0.80 or more, and the upper limit is preferably 5.00 or less, more preferably 3.00 or less, still more preferably 2. 00 or less. When the mass ratio of the hydroxyl group-containing amine compound (B) to the amine compound (D) is within the above range, the brake squeal prevention performance in particular can be efficiently improved due to the interaction of these components.

When containing an amine compound (C) and an amide compound (D), the mass ratio of the amine compound (C) to the amide compound (D) (content of the amine compound (C)/content of the amide compound (D)) is preferably 0.01 or more, more preferably 0.1 or more, even more preferably 0.3 or more, and the upper limit is preferably 3.00 or less, more preferably 1.50 or less, and even more preferably 1.00. It is as follows. When the mass ratio of the amine compound (C) and the amide compound (D) is within the above range, the interaction between these components and the hydroxyl group-containing amine compound (B) effectively improves brake squeal prevention performance in particular. can be done.

Further, the content of all nitrogen atoms based on the total amount of the composition is preferably 300 mass ppm or more, more preferably 350 mass ppm or more, and still more preferably 380 mass ppm or more, and there is no particular upper limit, but usually It is 2000 mass ppm or less, preferably 1500 mass ppm or less, more preferably 1000 mass ppm or less, and still more preferably 800 mass ppm or less. When the content of all nitrogen atoms based on the total amount of the composition is within the above range, the brake squeal prevention performance is effectively improved, as well as the seizure and wear prevention performance of the transmission, viscosity characteristics, and stability against oxidative deterioration. can be done.

(Other additives)
The lubricating oil composition of this embodiment includes, for example, a viscosity index improver, a friction modifier, a pour point depressant, an antifoaming agent, an anti-wear agent, an extreme pressure agent, an oil-based Other additives such as antioxidants, dispersants, metal detergents, metal deactivators, and rust preventives can be appropriately selected and blended. These additives can be used alone or in combination.
The total content of these other additives is not particularly limited as long as it does not contradict the purpose of the present invention, but considering the effect of adding other additives, it is 0.1 to 20% based on the total amount of the composition. It is preferably 1 to 15% by weight, and even more preferably 3 to 10% by weight.

(Various physical properties of lubricating oil composition)
The kinematic viscosity at 40° C. of the lubricating oil composition of the present embodiment is preferably 20 mm ² /s or more, more preferably 30 mm ² /s or more, even more preferably 40 mm ² /s or more, and the upper limit is preferably 80 mm ² /s or less, more preferably 70 mm ² /s or less, even more preferably 60 mm ² /s or less. The kinematic viscosity at 100° C. of the lubricating oil composition of the present embodiment is preferably 7 mm ² /s or more, more preferably 8 mm ² /s or more, even more preferably 8.5 mm ² /s or more, and the upper limit is preferably It is 12 mm ² /s or less, more preferably 11 mm ² /s or less, even more preferably 10 mm ² /s or less. Moreover, the viscosity index of the lubricating oil composition of this embodiment is preferably 130 or more, more preferably 135 or more, and even more preferably 140 or more. When the kinematic viscosity and viscosity index of the lubricating oil composition of the present embodiment are within the above ranges, the brake squeal prevention performance, the seizure and wear prevention performance of the transmission, the viscosity characteristics, the stability against oxidative deterioration, etc. are improved. It becomes easier.
Here, the methods for measuring the kinematic viscosity and viscosity index are the same as those for the above base oil.

The lubricating oil composition of this embodiment has been rated SAE No. 1 according to JASO M348:2002 (Automatic Transmission Friction Characteristics Test Method). The ratio (μ ₀ /μ _d ) using the coefficient of kinetic friction (μ ₀ ) and the coefficient of kinetic friction (μ _d ) measured and calculated after one cycle and after 5000 cycles of the dynamic friction test using a two-friction test device. , hereinafter referred to as friction coefficient ratio) is preferably 1 or less. When the friction coefficient ratio in the dynamic friction test (after 1 cycle and after 5000 cycles) is 1 or less, brake squeal prevention performance is exhibited from the initial stage over a long period of time. Here, the dynamic friction test, the calculation method of the dynamic friction coefficient (μ ₀ ), the dynamic friction coefficient (μ _d ), etc. are based on the methods described in Examples.

(Application)
The lubricating oil composition of the present embodiment has particularly excellent performance in preventing brake squeal, and also has performance that is generally required for lubricating oil compositions used in industrial machinery, such as seizure of transmissions. It also has anti-wear performance, viscosity characteristics, and stability against oxidative deterioration. Therefore, the lubricating oil composition of the present embodiment exhibits excellent effects in general industrial machines such as agricultural machines, construction machines, and transport machines that are equipped with transmissions (gears), hydraulic operating parts, etc. Suitable for use in these industrial machines. In particular, industrial machines equipped with transmissions (gears), hydraulic operating parts, and wet brakes, such as agricultural machines such as tractors, rice transplanters, binders, and combines, construction machines such as hydraulic excavators, crane trucks, and bulldozers, dump trucks, When commonly lubricating transportation machines such as forklifts, shovel loaders, rough terrain vehicles, etc., the brake squeal prevention performance can effectively function, so it is suitably used for these applications.

[Method for producing lubricating oil composition]
The method for producing a lubricating oil composition of the present embodiment includes the step of blending the base oil (A), the hydroxyl group-containing amine compound (B), and the amine compound (C). Further, in the method for producing a lubricating oil composition of the present embodiment, in the above step, preferably the above amide compound (D) is further blended.
The order in which the above components are blended is not particularly limited, and for example, the hydroxyl group-containing amine compound (B), the amine compound (C), and the more preferably used amide compound (D) are sequentially blended into the base oil (A). Alternatively, the hydroxyl group-containing amine compound (B), the amine compound (C) and the amide compound (D) may be mixed together in advance, or the amine compound (C) and the amide compound (D) may be mixed together. may be used by mixing them in advance.

[Lubrication method]
The lubrication method of this embodiment is a lubrication method using the above-mentioned lubricating oil composition of this embodiment. The lubricating oil composition used in the lubrication method of the present embodiment has particularly excellent brake squeal prevention performance, and also has excellent performance in preventing seizure and wear of transmissions, viscosity characteristics, and oxidative deterioration. It also has properties such as stability that are generally required for lubricating oil compositions used in industrial machinery.
Therefore, since the lubrication method of the present embodiment can effectively utilize the above-mentioned performance of the lubricant composition of the present embodiment, it can be applied to agricultural machinery, construction machinery, and transportation equipment equipped with transmissions (gears), hydraulic operating parts, etc. Suitable for use in general industrial machines such as machines. In particular, industrial machines equipped with transmissions (gears), hydraulic operating parts, and wet brakes, such as agricultural machines such as tractors, rice transplanters, binders, and combines, construction machines such as hydraulic excavators, crane trucks, and bulldozers, dump trucks, When commonly lubricating transport machines such as forklifts, shovel loaders, rough terrain vehicles, etc., the brake squeal prevention performance can be effectively utilized, so it is suitably used.

〔Industrial machinery〕
The industrial machine of this embodiment uses the lubricating oil composition of this embodiment described above, and is equipped with a transmission, a hydraulic operating section, and a wet brake. The industrial machines of this embodiment include, for example, agricultural machines such as tractors, rice transplanters, binders, and combines; construction machines such as hydraulic excavators, crane trucks, and bulldozers; dump trucks, forklifts, shovel loaders, and rough terrain vehicles; Examples include transportation machines. Moreover, in these industrial machines, it is preferable that they be commonly lubricated from the viewpoint of effectively utilizing the excellent performance of the lubricating oil composition of the present embodiment.

Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to these examples in any way.

Examples 1 and 2, Comparative Examples 1 and 2
Lubricating oil compositions were prepared with the blending amounts (mass%) shown in Table 1. Various tests were conducted on the obtained lubricating oil composition by the following methods to evaluate its physical properties. The evaluation results are shown in Table 1. The details of each component shown in Table 1 used in this example are as follows.
・Base oil 1 (A): 150N (neutral) hydrotreated mineral oil, 100°C kinematic viscosity: 5.3 mm ² /s, viscosity index: 116, API group 2
・Base oil 2 (A): 500N (neutral) hydrotreated mineral oil, 100°C kinematic viscosity: 10.5mm ² /s, viscosity index: 96, API group 2
- Hydroxyl group-containing amine compound (B): oleyl diethanolamine (in general formula (1), R ¹¹ is an n-octadecenyl group (oleyl group), and R ¹² and R ¹³ are ethylene groups), nitrogen atom content :4.0% by mass
- Amine compound 1 (C): monooleylamine (in general formula (2), R ²¹ is an n-octadecenyl group (oleyl group), and R ²² and R ²³ are hydrogen atoms), nitrogen atom content: 5.2% by mass
・Amide compound (D): Oleic acid amide ・Amine compound 2: Tertiary amine (dimethylstearylamine)
・Other additives: viscosity index improvers, pour point depressants, antifoaming agents, extreme pressure agents, antioxidants, etc.

The properties of the lubricating oil composition were measured by the following method.
(1) Kinematic viscosity Kinematic viscosity at 40°C and 100°C was measured in accordance with JIS K 2283:2000.
(2) Viscosity index (VI)
Measured in accordance with JIS K 2283:2000.
(3) Nitrogen atom content Measured in accordance with JIS K2609:1998.
(4) Calculation of dynamic friction coefficient (μ ₀ ), dynamic friction coefficient (μ _d ), and friction coefficient ratio (μ ₀ /μ _d ) by dynamic friction test The following dynamic friction test was performed for the lubricating oil compositions of each example and comparative example. The dynamic friction coefficient (μ ₀ ), the dynamic friction coefficient (μ _d ), and the friction coefficient ratio (μ ₀ /μ _d ) were calculated.
(Dynamic friction test; Friction test using SAE No. 2 test equipment according to JASO M348:2002 (Automatic transmission friction characteristics test method))
SAE No. A dynamic friction test was conducted under the following conditions using a 2 test device, and the friction torque was measured at the rotation speed (1200 rpm) for calculating the dynamic friction coefficient (μ _d ) and the rotation speed (80 rpm) for calculating the dynamic friction coefficient (μ ₀ ). (T _d , T ₀ ) were measured, and the dynamic friction coefficients (μ _d , μ ₀ ) at these friction torques were calculated using the following formula (1), and the friction coefficient ratio (μ ₀ /μ _d ) was calculated. .

μ: Dynamic friction coefficient T: Friction torque (Nm)
n: Number of friction discs (3 discs)
re: Average effective radius of friction (20mm)
P: Pressing load (1962kPa)
A: Friction area (3142mm ² )

(Test condition)
・How to assemble friction material: steel plate / sintered material / steel plate ・Moment of inertia of inertia disk: 0.207 kg・m ²
・Test rotation speed: 3000±50rpm
・Rotation start-up time: 8±2 seconds ・Oil temperature: 95±5℃
・Oil amount: 700ml
・Friction plate surface pressure: 1962kPa
・Test cycle: 30 seconds/cycle ・Rise time of pressing load: 0.1 to 0.15 seconds ・Holding time of pressing load: 5 seconds ・Number of tests: 1 cycle or 5000 cycles ・Wrapping temperature: 60°C
・Number of lapping: 100 cycles ・Rotation speed for calculating dynamic friction coefficient (μ _d ): 1200 rpm
・Rotation speed for calculating dynamic friction coefficient (μ ₀ ): 80 rpm

Note) *1 to 3 in Table 1 are as follows.
*1, Mass ratio of hydroxyl group-containing amine compound (B) and amine compound 1 (C).
*2, Mass ratio of hydroxyl group-containing amine compound (B) and amide compound (D).
*3, Mass ratio of amine compound 1 (C) and amide compound (D).

From the results of Examples 1 and 2, the lubricating oil composition of this embodiment has a friction coefficient ratio of 1 or less in both the friction tests (after 1 cycle and after 5000 cycles), and provides excellent braking from the initial stage over a long period of time. It was confirmed that squeal prevention performance was exhibited. Furthermore, since the friction coefficient ratio after 5000 cycles was about the same or lower than after 1 cycle, the lubricating oil composition of this embodiment exhibits excellent brake squeal prevention performance over a longer period of time. It can be said that there is. On the other hand, the lubricating oil compositions of Comparative Examples 1 and 2 that do not contain amine compound (C) but instead contain amine compound 2 exhibit brake squeal prevention performance initially, but do not exhibit brake squeal prevention performance over a long period of time. It was confirmed that there was no.

The lubricating oil composition of the present embodiment is a lubricating oil composition having excellent brake squeal prevention performance, and the lubricating oil composition and the lubrication method using the same can be applied to, for example, agricultural machinery, construction machinery, transportation machinery, etc. This is a general industrial machine, and is suitably used for an industrial machine equipped with a transmission (gear), a hydraulic operating part, etc. In particular, industrial machines equipped with transmissions (gears), hydraulic operating parts, and wet brakes, such as agricultural machines such as tractors, rice transplanters, binders, and combines, construction machines such as hydraulic excavators, crane trucks, and bulldozers, dump trucks, Suitable for use in transportation machines such as forklifts, shovel loaders, and rough terrain vehicles.

Claims (12)

A lubricating oil composition containing a base oil (A), a hydroxyl group-containing amine compound (B) represented by the following general formula (1), and an amine compound (C) represented by the following general formula (2). And,
Furthermore, it contains an amide compound (D) represented by the following general formula (3),
The mass ratio of the hydroxyl group-containing amine compound (B) and the amide compound (D) (hydroxyl group-containing amine compound (B)/amide compound (D)) is 0.10 or more and 5.00 or less,
The mass ratio of the amine compound (C) and the amide compound (D) (amine compound (C)/amide compound (D)) is 0.01 or more and 3.00 or less,
A lubricating oil composition for wet brakes having a kinematic viscosity of 7 to 12 mm ² /s at 100°C.

(In general formula (1), R ¹¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ¹² and R ¹³ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms.)

(In general formula (2), R ²¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ²² and R ²³ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms. , at least one of R ²² and R ²³ is a hydrogen atom.)

(In general formula (3), R ³¹ is an organic group having 1 to 30 carbon atoms, and R ³² and R ³³ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms.) The lubricating oil composition according to claim 1, wherein the content of all nitrogen atoms based on the total amount of the composition is 300 mass ppm or more. The lubricating oil composition according to claim 1 or 2, wherein the content of the hydroxyl group-containing amine compound (B) based on the total amount of the composition is 0.05% by mass or more and 1.0% by mass or less. The mass ratio of the hydroxyl group-containing amine compound (B) and the amine compound (C) (hydroxyl group-containing amine compound (B)/amine compound (C)) is 0.10 or more and 10.00 or less. 3. The lubricating oil composition according to any one of 3. In general formula (1), R ¹¹ is an alkyl group or alkenyl group having 12 to 30 carbon atoms, and R ¹² and R ¹³ are each independently an alkylene group having 1 to 5 carbon atoms or an alkenylene group having 2 to 5 carbon atoms. The lubricating oil composition according to any one of claims 1 to 4. The lubricating oil composition according to any one of claims 1 to 5, wherein in general formula (2), R ²¹ is an alkyl group or alkenyl group having 12 to 30 carbon atoms, and R ²² and R ²³ are hydrogen atoms. thing. The lubricating oil composition according to any one of claims 1 to 6, wherein in general formula (3), R ³¹ is an alkyl group or alkenyl group having 12 to 30 carbon atoms, and R ³² and R ³³ are hydrogen atoms. thing. The lubricating oil composition according to any one of claims 1 to 7, which has a viscosity index of 130 or more. A lubrication process comprising the step of blending a base oil (A), a hydroxyl group-containing amine compound (B) represented by the following general formula (1), and an amine compound (C) represented by the following general formula (2). A method for producing an oil composition, comprising:
A method for producing a lubricating oil composition for wet brakes , further comprising the step of blending an amide compound (D) represented by the following general formula (3).

(In general formula (1), R ¹¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ¹² and R ¹³ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms.)

(In general formula (2), R ²¹ is an aliphatic hydrocarbon group having 12 to 30 carbon atoms, and R ²² and R ²³ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms. , at least one of R ²² and R ²³ is a hydrogen atom.)

(In general formula (3), R ³¹ is an organic group having 1 to 30 carbon atoms, and R ³² and R ³³ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms.) A lubrication method using the lubricating oil composition according to any one of claims 1 to 8 . The lubrication method according to claim 10 , for lubricating an industrial machine equipped with a wet brake. An industrial machine using the lubricating oil composition according to any one of claims 1 to 8 and equipped with a wet brake.