JP2001311090A - Lubricating oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lubricating oil composition having excellent extreme pressure properties and frictional properties, suitably useful as a lubricating oil for power transmission mechanism especially as a manual or an automatic transmission oil of automobile or a lubricating oil for common lubrication of a tractor and a building machine. SOLUTION: This lubricating oil composition having excellent extreme pressure properties and frictional properties is obtained by adding 0.01-10.0 mass % based on the total of the composition of a polysulfide compound of formula (1) (R1 and R3 are each a 6-30C alkyl group or alkenyl group; R2 is a 6-30C alkylene group; x and y are each independently 1-15; n is 0-2) to a base oil of lubricating oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil composition, and more particularly to a lubricating oil composition having excellent friction characteristics and durability, and particularly used in a mechanism having a portion affected by friction. . Specifically, it is used for power transmission mechanisms such as lubricating oil for manual transmission or automatic transmission using a synchronizer ring, and lubricating oil for common lubrication that simultaneously lubricates transmissions and brakes used in tractors and construction machinery. The present invention relates to a lubricating oil composition particularly suitable for use as a lubricating oil.

[0002]

2. Description of the Related Art In general, an additive mainly containing a sulfur-based additive and a phosphorus-based additive called an SP-based additive is used in gear oil. This is because this additive has a performance called extreme pressure resistance, which is excellent in abrasion resistance and seizure resistance.
However, in a manual or automatic transmission for automobiles that uses a synchronizer ring for the synchromesh mechanism, if there is not a sufficient kinetic friction coefficient between the synchronizer ring and the gear cone during shifting, it takes time to shift without easily synchronizing or shifting operation. Requires excessive force. If the coefficient of static friction between the synchronizer ring and the gear cone is high during gear shifting, a problem called catching is likely to occur. This is because it is necessary to slide the synchronizer ring that has once stopped slightly on the gear cone during the shifting operation, and if the coefficient of static friction at this time is high, catching occurs.

[0003] It is known that conventionally used SP additives deteriorate the friction characteristics. In particular, known polysulfides, which are one of the main components of the SP-based additive, promote abrasion of the copper-based synchronizer ring, causing a sharp decrease in the coefficient of dynamic friction. With the lubricating oil composition for manual or automatic transmissions described above, sufficient shifting operability was not obtained. On the other hand, in tractors and construction machinery, transmissions and wheel brakes are mostly lubricated with the same lubricant. For this reason, the lubricating oil used is required to have a high extreme pressure property as a gear oil and at the same time a performance of preventing brake noise. Brake squeal is generated by stick-slip or self-excited vibration of a wet brake (a brake using a wet friction mechanism). In order to prevent this, a lubricating oil composition to which a friction modifier having a characteristic of lowering the friction coefficient under a low-speed sliding condition is added is used. However, the performance of conventional lubricating oil compositions for tractors or construction machines was not satisfactory, and often caused brake squeals and product complaints.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of such circumstances, and its object is to provide:
In particular, a lubricating oil composition having excellent extreme pressure properties and friction characteristics, which is suitable for use as a lubricating oil for a power transmission mechanism such as a manual or automatic transmission oil for automobiles and a common lubricating oil for tractors and construction machinery. Is to provide.

[0005]

That is, the present invention provides a lubricating base oil containing 0.01 to 10.0% by mass of a polysulfide compound represented by the following general formula (1) based on the total amount of the composition. It is a lubricating oil composition characterized by comprising:

[0006]

Embedded image (In the formula (1), R ¹ and R ³ are an alkyl group or an alkenyl group having 6 to 30 carbon atoms, which may be the same or different, and R ² is an alkylene group having 6 to 30 carbon atoms. X and y are each independently 1 to 15, and n is 0 to 2.)

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the contents of the present invention will be described in more detail. The lubricating oil composition of the present invention, a lubricating base oil,
(A) The composition contains 0.01 to 10.0% by mass of a polysulfide compound represented by the following general formula (1) based on the total amount of the composition.

[0008]

Embedded image (In the formula (1), R ¹ and R ³ are an alkyl group or an alkenyl group having 6 to 30 carbon atoms, which may be the same or different, and R ² is an alkylene group having 6 to 30 carbon atoms. X and y are each independently 1 to 15, and n is 0 to 2.)

In the formula (1), R ¹ and R ³ are each independently an alkyl or alkenyl group having 6 to 30 carbon atoms. R ² is an alkylene group having 6 to 30 carbon atoms.
When the number of carbon atoms of R ^{1 to} R ³ is less than 6 or more than 30, the frictional characteristics of the lubricating oil deteriorate, which is not preferable.
Further, from the viewpoint of the effect of reducing the coefficient of static friction, R ^{1 to} R ³ preferably have 10 to 30 carbon atoms, and 12 to 24 carbon atoms.
Is particularly preferred. Further, x and y are each independently an integer of 1 to 15, but are preferably 10 or less from the viewpoint of stability and corrosiveness as a compound. Note that _{x in} each repeating unit represented by [-(S) _x -R ^2- ] _n is independent of x in other repeating units, and may be different from or the same as each other. good.

As R ¹ and R ³ , specifically, for example, hexyl group, heptyl group, octyl group, nonyl group,
Decyl group, undecyl group, dodecyl group, tridecyl group,
Tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henycosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl Alkyl groups such as these may be linear or branched; hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, Hexadecenyl group, heptadecenyl group, octadecenyl group, nonadecenyl group, icosenyl group, henicocenyl group, docosenyl group, tricosenyl group, tetracosenyl group, pentacosenyl group, hexacosenyl group, heptacoseni Group, Okutakoseniru group, Nonakoseniru group, alkenyl groups such as tri Conte sulfonyl group (these alkenyl groups may be branched be linear, also the position of the double bond is also arbitrary); and the like. Further, the alkyl group or the alkenyl group is preferably linear in terms of excellent friction characteristics. Further, an alkyl group is preferable from the viewpoint of oxidation stability.

Specific examples of R ² include hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, tridecylene, tetradecylene, pentadecylene, hexadecylene, heptadecylene, and octadecylene. Alkylene groups such as a group, a nonadecylene group, an icosylene group, a hencicosylene group, a docosylene group, a tricosylene group, a tetracosylene group, a pentacosylene group, a hexacosylene group, a heptacosylene group, an octacosylene group, a nonacosylene group, and a tricontylene group. May be linear or branched).

The sulfur content in the polysulfide compound of the present invention is not particularly limited, but the lower limit is 5% by mass, preferably 15% by mass. If the content of sulfur is too small, the reactivity as a compound may decrease, or the extreme pressure property may decrease. The upper limit is 70% by mass, preferably 60% by mass. If the sulfur content is too high, the compound may become unstable, causing a problem in storage stability, or the reactivity may be too high to increase the corrosiveness. Further, in the lubricating oil composition of the present invention, a mixture of two or more kinds of polysulfide compounds having different structures represented by the formula (1) can be used as the polysulfide compound.

In the lubricating oil composition of the present invention, the polysulfide compound represented by the formula (1) (hereinafter referred to as (A)
Also called a component. ), When the lubricating oil composition is used in a manual or automatic transmission, a tractor or construction machine, a synchronizer ring used in a manual or automatic transmission, or used in a tractor or construction machine The coefficient of dynamic friction (μ _d ) of the copper alloy, which is the material of the wet brake, can be kept high, and the coefficient of static friction (μ _s ) can be reduced. The lower limit of the content of the component (A) in the lubricating oil composition of the present invention is 0.01% by mass, and preferably 0.05% by mass, based on the total amount of the composition, while the upper limit of the composition is 10.0 based on the total amount
% By mass, preferably 5.0% by mass. The content of the polysulfide compound of the present invention is 0.0% based on the total amount of the composition.
If the amount is less than 1% by mass, the effect of improving the extreme pressure property and the frictional properties by the polysulfide compound is poor,
On the other hand, when the content exceeds 10.0% by mass based on the total amount of the composition, the corrosiveness of polysulfide becomes too large, which is not preferable.

Further, as the base oil in the lubricating oil composition of the present invention, any mineral oil and / or synthetic oil used as a base oil for ordinary lubricating oils can be used. As a mineral oil, for example, a lubricating oil fraction obtained by distilling atmospheric pressure residual oil obtained by atmospheric distillation of crude oil under reduced pressure is subjected to solvent removal, solvent extraction, hydrocracking, solvent dewaxing, and catalytic dewatering. Paraffinic and naphthenic oils and normal paraffins purified by appropriately combining various purification treatments such as wax, hydrorefining, sulfuric acid washing, and clay treatment can be used.

[0015] The synthetic oil is not particularly limited.
Poly-α-olefin (1-octene oligomer, 1-
Decene oligomers, ethylene-propylene oligomers and the like, hydrides thereof, isobutene oligomers and their hydrides, isoparaffin, alkylbenzene, alkylnaphthalene, diesters (ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditridecyl adipate, di2 -Ethylhexyl sebacate, etc.), polyol esters (trimethylolpropane caprylate, trimethylolpropane pelargonate, pentaerythritol 2-ethylhexanoate, pentaerythritol pelargonate, etc.),
Polyoxyalkylene glycol, dialkyl diphenyl ether, polyphenyl ether and the like can be used. The kinematic viscosities of these lubricating base oils are not particularly limited and are arbitrary.
50 mm ² / s, preferably it is desirable to use those which are 2 to 20 mm ² / s.

The lubricating oil composition of the present invention may further contain (B) a phosphorus compound. By using a phosphorus compound (hereinafter also referred to as a component (B)) in combination, it is possible to further improve the extreme pressure performance of the lubricating oil composition and exhibit excellent friction characteristics from the beginning. Specific examples of the phosphorus compound as the component (B) include a phosphoric ester represented by the following general formula (2) and the following general formula (3)
And one or a mixture of two or more compounds selected from derivatives of these phosphorus compounds.

[0017]

Embedded image In the formula (2), R ⁴ , R ⁵ and R ⁶ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, and
At least one of R ⁴ , R ⁵ and R ⁶ is a hydrocarbon group, and X ¹ , X ² , X ³ and X ⁴ each independently represent an oxygen atom or a sulfur atom.

[0018]

Embedded image In the formula (3), R ⁷ , R ⁸ and R ⁹ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms;
At least one of R ⁷ , R ⁸ and R ⁹ is a hydrocarbon group, and X ⁵ , X ⁶ and X ⁷ each independently represent an oxygen atom or a sulfur atom.

As described above, R^Four, R^Five, R⁶, R⁷, R
⁸And R⁹Is independently a hydrogen atom or a carbon number 1 to
30 hydrocarbon groups, preferably a hydrogen atom or carbon
3 to 30 hydrocarbon groups, more preferably a hydrogen atom or
It represents a hydrocarbon group having 4 to 24 carbon atoms. Where R^Four, R^Five
And R⁶At least one of which is a hydrocarbon group,
R⁷, R⁸And R⁹At least one of which is a hydrocarbon group
is there. R^Four, R^Five, R⁶, R ⁷, R⁸And R⁹Hydrocarbon group
If the carbon number of the lubricant exceeds 30, the friction characteristics of the lubricating oil composition
It is not preferable because the property is deteriorated.

Specific examples of such a hydrocarbon group having 1 to 30 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group and a nonyl group. , Decyl group, undecyl group,
Dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henycosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl , A nonacosyl group, an alkyl group such as a triacontyl group (these alkyl groups may be linear or branched); a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, an undecenyl group, Dodecenyl group, tridecenyl group, tetradecenyl group, pentadecenyl group, hexadecenyl group, heptadecenyl group, octadecenyl group, nonadecenyl group, icosenyl group, henicocenyl group, docosenyl group, tricosenyl group, tetracosenyl Alkenyl groups such as pentacosenyl group, hexacosenyl group, heptacosenyl group, octacosenyl group, nonacosenyl group, and triaconenyl group (these alkenyl groups may be linear or branched, and the position of the double bond is arbitrary) A cycloalkyl group having 5 to 7 carbon atoms such as a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group; a methylcyclopentyl group, a dimethylcyclopentyl group, a methylethylcyclopentyl group, a diethylcyclopentyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, and a methylethylcyclohexyl Group, diethylcyclohexyl group, methylcycloheptyl group, dimethylcycloheptyl group, methylethylcycloheptyl group, diethylcycloheptyl group, etc.
1 alkylcycloalkyl group (the substitution position of the alkyl group is arbitrary); aryl groups such as phenyl group and naphthyl group: tolyl group, xylyl group, ethylphenyl group, propylphenyl group, butylphenyl group, pentylphenyl group, Hexylphenyl group, heptylphenyl group, octylphenyl group, nonylphenyl group, decylphenyl group,
C7-C18 alkylaryl groups such as undecylphenyl group and dodecylphenyl group (the alkyl group may be linear or branched, and the position of the double bond is arbitrary); benzyl group, phenyl Each arylalkyl group having 7 to 12 carbon atoms such as an ethyl group, a phenylpropyl group, a phenylbutyl group, a phenylpentyl group, and a phenylhexyl group (the alkyl group may be linear or branched; Are also optional), and among these, an alkyl group, an alkenyl group, an aryl group or an alkylaryl group is preferable.

As the derivative of the phosphorus compound, specifically, for example, phosphoric acid, phosphorous acid, one or two of R ⁴ , R ⁵ and R ^{6 in} the above formula (2) are hydrogen. Phosphorus compounds such as acidic phosphoric acid esters or acidic phosphites in which one or two of R ⁷ , R ⁸ and R ^{9 in} the formula (3) are hydrogen may be treated with ammonia or carbonized carbon atoms having 1 to 8 carbon atoms. Salts obtained by acting a nitrogen-containing compound such as an amine compound containing only a hydrogen group or a hydroxyl group-containing hydrocarbon group in a molecule to neutralize a part or all of the remaining acidic hydrogen are exemplified.

Specific examples of the nitrogen-containing compound include ammonia; monomethylamine, monoethylamine, monopropylamine, monobutylamine, monopentylamine, monohexylamine, monoheptylamine, monooctylamine, dimethylamine, and the like. Methylethylamine, diethylamine, methylpropylamine, ethylpropylamine, dipropylamine, methylbutylamine, ethylbutylamine, propylbutylamine,
Alkylamines such as dibutylamine, dipentylamine, dihexylamine, diheptylamine and dioctylamine (the alkyl group may be linear or branched); monomethanolamine, monoethanolamine, monopropanolamine, monobutanolamine, Monopentanolamine, monohexanolamine, monoheptanolamine, monooctanolamine, monononanolamine, dimethanolamine, methanolethanolamine, diethanolamine, methanolpropanolamine, ethanolpropanolamine, dipropanolamine, methanolbutanolamine, ethanolbutanol Amine, propanol butanolamine, dibutanolamine, dipentanolamine, dihexanolamine, diheptano Amines, alkanolamines such as di-octanol amine (alkanol group may be and straight-chain or branched); and mixtures thereof.

As the phosphorus compound of the component (B), R ⁴ ,
An acidic phosphate ester in which one or two of R ⁵ and R ⁶ are hydrogen, or R ⁷ , R ⁸ and R in the above formula (3)
One or two acid phosphite is hydrogen out of ^9, or amine salts of these phosphorus-based compounds as described above, alkanolamine salts are more preferably used.

Particularly preferred compounds as component (B) are, for example, monobutyl phosphate, monopentyl phosphate, monohexyl phosphate, monoheptyl phosphate, monooctyl phosphate, monononyl phosphate, monodecyl phosphate and monounphosphate. Decyl phosphate, monododecyl phosphate, monotridecyl phosphate, monotetradecyl phosphate, monopentadecyl phosphate, monohexadecyl phosphate, monoheptadecyl phosphate, monooctadecyl phosphate, monononadecyl phosphate, monoicosyl phosphate, monohenicosyl Monoalkyl phosphates such as phosphate, monodocosyl phosphate, monotricosyl phosphate, monotetracosyl phosphate, etc. Preparative (the alkyl group may be a branched be linear, or may be a thiophosphate); monoalkenyl phosphate (alkenyl groups such as mono-octadecenyl phosphate may be and straight-chain or branched,
The position of the double bond is also arbitrary and may be thiophosphate); mono (alkyl) aryl phosphates such as monophenyl phosphate and monocresyl phosphate (the substitution position of the alkyl group is arbitrary, and thiophosphate is optional. Dibutyl phosphate, dipentyl phosphate, dihexyl phosphate, dipeptyl phosphate, dioctyl phosphate, dinonyl phosphate, didecyl phosphate, jinundecyl phosphate, didodecyl phosphate,
Ditridecyl phosphate, ditetradecyl phosphate, dipentadecyl phosphate, dihexadecyl phosphate, diheptadecyl phosphate, dioctadecyl phosphate, dinonadecyl phosphate, diicosyl phosphate, dihenicosyl phosphate, didocosyl phosphate, dididecyl phosphate Dialkyl phosphates such as tricosyl phosphate and ditetracosyl phosphate (the alkyl group may be linear or branched, or thiophosphate); dialkenyl phosphates such as dioctadecenyl phosphate (alkenyl group) May be linear or branched, the position of the double bond is arbitrary,
A thiophosphate); di (alkyl) aryl phosphates such as diphenyl phosphate and dicresyl phosphate (the substitution position of the alkyl group is arbitrary and may be thiophosphate); monobutyl phosphite; Monopentyl phosphite, monohexyl phosphite, monopeptyl phosphite,
Monooctyl phosphite, monononyl phosphite,
Monodecyl phosphite, monoundecyl phosphite, monododecyl phosphite, monotridecyl phosphite, monotetradecyl phosphite, monopentadecyl phosphite, monohexadecyl phosphite, monoheptadecyl phosphite, monooctadecyl phosphite , Monononadecyl phosphite, monoicosyl phosphite, monohenicosyl phosphite, monodocosyl phosphite, monotricosyl phosphite, monotetracosyl phosphite, etc. Monoalkenyl phosphites such as monooctadecenyl phosphite (alkenyl groups may be linear or branched, and may have a double bond). The position is arbitrary, and Mono (alkyl) aryl phosphites such as monophenyl phosphite and monocresyl phosphite (the substitution position of the alkyl group is arbitrary and may be thiophosphite); dibutyl Phosphite, dipentyl phosphite, dihexyl phosphite, dipeptyl phosphite, dioctyl phosphite, dinonyl phosphite, didecyl phosphite, gin undecyl phosphite, didodecyl phosphite, ditridecyl phosphite, ditetradecyl phosphite Phyte, dipentadecyl phosphite, dihexadecyl phosphite, diheptadecyl phosphite, dioctadecyl phosphite, dinonadecyl phosphite, diicosyl phosphite, dihen icosyl phosphite, didokosyl phosphite Dialkyl phosphites such as graphite, ditricosyl phosphite, ditetracosyl phosphite (the alkyl group may be linear or branched, or thiophosphite); dioctadecenyl phosphite (Alkenyl groups may be linear or branched, the position of the double bond may be arbitrary, and may be thiophosphite); diphenyl phosphite, dicresyl phosphite, etc. (The substitution position of the alkyl group is arbitrary and may be thiophosphite); salts of these phosphorus compounds with the above-mentioned amines and alkanolamines; or Mixtures and the like can be mentioned.

The component (B) is represented by R ⁴ and R ⁵ of the formula (2).
Or one or two of R ⁶ , or formula (3)
Wherein one or two of R ⁷ , R ⁸ or R ⁹ have an alkyl group or an alkenyl group having 6 or more carbon atoms, preferably 9 or more carbon atoms, more preferably a lauryl group, a myristyl group, a palmityl group, or a stearyl group. A phosphoric acid ester (or a thiophosphoric acid ester) or a phosphite (or a thiophosphorous acid ester) which is a linear alkyl group or a linear alkenyl group such as oleyl group, and the other is a hydrogen atom Is particularly preferable since the effect of improving the initial conformability of the lubricating oil composition is large.

When one or more components (B) arbitrarily selected in the lubricating oil composition of the present invention are used in combination, the lower limit of the content is set to 0 as phosphorus element amount based on the total amount of the composition. 0.005% by mass, preferably 0.01% by mass, while the upper limit is 0.5% by mass, preferably 0.3% by mass as the amount of phosphorus element based on the total amount of the composition. When the content of the component (B) is less than 0.005% by mass as the phosphorus element amount based on the total amount of the composition, the effect of improving the extreme pressure property and the initial adaptability of the lubricating oil composition by using the component (B) are improved. When the effect is poor, on the other hand, when the content exceeds 0.5% by mass as the phosphorus element amount based on the total amount of the composition,
Each of these is not preferable because the corrosiveness of the lubricating oil composition may increase or the durability of the sealing material or the resin material may be adversely affected.

The lubricating oil composition of the present invention may further contain (C) a friction modifier containing no phosphorus. The lubricating oil composition containing the polysulfide compound (A) according to the present invention has excellent friction characteristics and durability, but requires a higher effect due to friction characteristics such as cyclonizer ring and wet brake. There is.
In this case, by using a phosphorus-free friction modifier (hereinafter also referred to as component (C)) in combination, more excellent friction characteristics can be exhibited. As the component (C), any compound usually used as a friction modifier for lubricating oils can be used. Particularly, a compound having at least one alkyl group or alkenyl group having 6 to 30 carbon atoms in the molecule can be used. preferable. The alkyl group or the alkenyl group may be linear or branched, and is preferably a compound having 6 to 30, preferably 9 to 24 carbon atoms. When the number of carbon atoms of the alkyl group or the alkenyl group is less than 6 or more than 30,
Since the friction characteristics of the lubricating oil composition are deteriorated, each is not preferable.

Examples of the alkyl group or alkenyl group include, for example, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group,
Hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henycosyl group, docosyl group, tricosyl group, tetracosyl group, pentacosyl group,
Alkyl groups such as a hexacosyl group, a heptacosyl group, an octakosyl group, a nonacosyl group, and a triacontyl group (these alkyl groups may be linear or branched); a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group; Undecenyl group, dodecenyl group, tridecenyl group, tetradecenyl group, pentadecenyl group, hexadecenyl group, heptadecenyl group, octadecenyl group, nonadecenyl group, icosenyl group, henicocenyl group, docosenyl group, tricosenyl group, tetracosenyl group, pentacosenyl group, hexacosenyl group, hexacosenyl group, hexacosenyl group Alkenyl groups such as octacocenyl group, nonacocenyl group and triacontenyl group (these alkenyl groups may be linear or branched, and the position of the double bond is arbitrary);

Specific examples of the friction modifier (C) include (C-1) an amine compound having at least one alkyl or alkenyl group having 6 to 30 carbon atoms in the molecule, or a derivative thereof. , (C-2) an ester, amide, imide or metal salt of a fatty acid having at least one alkyl group or alkenyl group having 6 to 30 carbon atoms in the molecule;
Preferred compounds include one or more compounds selected from sulfides of unsaturated fatty acid esters. As the amine compound (C-1), more specifically, for example, an aliphatic monoamine represented by the following general formula (4) or an alkylene oxide adduct thereof, and a compound represented by the following general formula (5) And aliphatic polyamines represented by the general formula (6) and imidazoline compounds represented by the general formula (6).

[0030]

Embedded image In the formula (4), R ¹⁰ has 6 to 30 carbon atoms, preferably ⁹ to 2 carbon atoms.
4 represents an alkyl group or an alkenyl group, and R ¹¹ and R ¹²
Each independently represents an ethylene group or a propylene group,
R ¹³ and R ¹⁴ are each independently hydrogen or a group having 1 to 30 carbon atoms.
Wherein a and b each independently represent 0 to 0
10, preferably an integer of 0 to 6, and a + b = 0
-10, preferably 0-6.

[0031]

Embedded image In the formula (5), R ¹⁵ has 6 to 30 carbon atoms, preferably 9 to 2 carbon atoms.
4 represents an alkyl group or an alkenyl group; R ¹⁶ represents an ethylene group or a propylene group; R ¹⁷ and R ¹⁸ each independently represent hydrogen or a hydrocarbon group having 1 to 30 carbon atoms;
Represents an integer of 1 to 5, preferably 1 to 4.

[0032]

Embedded image In the formula (6), R ¹⁹ has 6 to 30 carbon atoms, preferably 9 to 2 carbon atoms.
4 represents an alkyl group or an alkenyl group, R ²⁰ represents an ethylene group or a propylene group, and R ²¹ represents hydrogen or carbon atom 1
And d is an integer of 0 to 10, preferably 0 to 6.

The alkyl group or alkenyl group for R ¹⁰ , R ¹⁵ and R ¹⁹ may be linear or branched, but preferably has 6 to 30, preferably 9 to 24 carbon atoms. When the number of carbon atoms of the alkyl group or the alkenyl group is less than 6 or more than 30, the friction characteristics of the lubricating oil composition deteriorate, which is not preferable. Specific examples of the alkyl group or alkenyl group represented by R ¹⁰ , R ¹⁵ and R ¹⁹ include various alkyl groups and alkenyl groups as described above.From the viewpoint of more excellent friction characteristics, a lauryl group, Myristyl group, palmityl group, stearyl group,
A straight-chain alkyl or alkenyl group having 12 to 18 carbon atoms such as an oleyl group is particularly preferred.

Examples of the group represented by R ¹³ , R ¹⁴ , R ¹⁷ , R ¹⁸ and R ²¹ include hydrogen; methyl, ethyl, propyl, butyl, pentyl, hexyl,
Heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group,
Alkyl such as pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henycosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, etc. Groups (these alkyl groups may be straight-chain or branched); butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl , Pentadecenyl group, hexadecenyl group, heptadecenyl group, octadecenyl group, nonadecenyl group,
Alkenyl groups such as icosenyl group, henicocenyl group, docosenyl group, tricosenyl group, tetracosenyl group, pentacosenyl group, hexacosenyl group, heptacosenyl group, octacosenyl group, nonacosenyl group, triacontenyl group and the like (these alkenyl groups may be linear or branched. A cycloalkyl group having 5 to 7 carbon atoms such as a cyclopentyl group, a cyclohexyl group and a cycloheptyl group; a methylcyclopentyl group;
Dimethylcyclopentyl, methylethylcyclopentyl, diethylcyclopentyl, methylcyclohexyl, dimethylcyclohexyl, methylethylcyclohexyl, diethylcyclohexyl, methylcycloheptyl, dimethylcycloheptyl, methylethylcycloheptyl, diethylcycloheptyl An alkylcycloalkyl group having 6 to 11 carbon atoms, such as a phenyl group;
Aryl groups such as naphthyl group: tolyl group, xylyl group, ethylphenyl group, propylphenyl group, butylphenyl group, pentylphenyl group, hexylphenyl group, heptylphenyl group, octylphenyl group, nonylphenyl group, decylphenyl group, unylphenyl group C7-C18 alkylaryl groups such as decylphenyl group and dodecylphenyl group (the alkyl group may be linear or branched, and the substitution position is arbitrary); benzyl group, phenylethyl group,
Each arylalkyl group having 7 to 12 carbon atoms such as a phenylpropyl group, a phenylbutyl group, a phenylpentyl group, and a phenylhexyl group (the alkyl group may be linear or branched, and the substitution position is arbitrary); And the like.

As the aliphatic monoamine represented by the formula (4) or the alkylene oxide adduct thereof, R ¹³ and R ¹⁴ in the formula (4) are superior in terms of friction characteristics.
Is independently hydrogen or an alkyl group having 1 to 6 carbon atoms,
An aliphatic monoamine wherein a = b = 0 and R ¹³ and R
¹⁴ is hydrogen, and a and b are independently 0-6,
An alkylene oxide adduct of an aliphatic monoamine with + b = 1 to 6 is more preferably used. Also,
The aliphatic polyamine represented by the formula (5) is preferably an aliphatic polyamine represented by the formula (5), wherein R ¹⁷ and R ¹⁸ are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms, because of its superior frictional properties. Group polyamines are more preferably used. Further, as the imidazoline compound represented by the formula (6), the compound having the formula (6)
^An imidazoline compound in which ²¹ is hydrogen or an alkyl group having 1 to 6 carbon atoms is more preferably used.

On the other hand, examples of the derivative of the amine compound referred to in (C-1) include amine compounds represented by the above formulas (4) to (6) and monocarboxylic acids having 2 to 30 carbon atoms (such as fatty acids). By reacting a polycarboxylic acid having 2 to 30 carbon atoms such as oxalic acid, phthalic acid, trimellitic acid and pyromellitic acid to neutralize a part or all of the remaining amino group and / or imino group, Amidated, so-called acid-modified compound; a so-called acid-modified compound in which boric acid is allowed to act on an amine compound represented by formulas (4) to (6) to neutralize part or all of the remaining amino group and / or imino group. Boric acid-modified compounds;
A so-called alkylene oxide adduct of an amine compound obtained by reacting an amine compound represented by the formula (4) or (6) with an alkylene oxide such as ethylene oxide or propylene oxide; a combination of two or more modifications selected from these. And a modified amine compound obtained by the above method.

As the amine compound (C-1) or a derivative thereof, specifically, laurylamine, lauryldiethylamine, lauryldiethanolamine, dodecyldipropanolamine, palmitylamine, stearylamine, etc. Amine compounds such as stearyltetraethylenepentamine, oleylamine, oleylpropylenediamine, oleyldiethanolamine, N-hydroxyethyloleylimidazoline; alkylene oxide adducts of these amine compounds; alkylene oxide adducts of these amine compounds; or mixtures thereof. Particularly preferably used.

The fatty acid in the fatty acid ester, fatty acid amide, fatty acid imide or fatty acid metal salt of (C-2) may be a linear fatty acid or a branched fatty acid, a saturated fatty acid or an unsaturated fatty acid. Alternatively, the carbon number of the alkenyl group is 6 to 30, preferably 9 to 2
4 is desirable. The same applies to hydrocarbon groups of sulfides of unsaturated fatty acid esters. When the number of carbon atoms of the alkyl group or alkenyl group of the fatty acid is less than 6 or more than 30, the friction characteristics of the wet clutch deteriorate, which is not preferable.

Examples of the fatty acid include heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecane Saturated fatty acids such as acid, icosanoic acid, henicicosanoic acid, docosanoic acid, tricosanoic acid, tetracosanoic acid, pentacosanoic acid, hexacosanoic acid, heptacosanoic acid, octacosanoic acid, nonacosanoic acid, and triacontanic acid (saturated fatty acids are linear or branched. Heptenoic acid, octenoic acid, nonenoic acid, decenoic acid, undecenoic acid, dodecenoic acid, tridecenoic acid, tetradecenoic acid, pentadecenoic acid, hexadecenoic acid, heptadecenoic acid, octadecenenoic acid, nonadecenoic acid, icosenoic acid, henicicosenic acid, dococene Acid, tricho Unsaturated fatty acids such as acid, tetracosenoic acid, pentacosenoic acid, hexacosenoic acid, heptacosenoic acid, octacosenoic acid, nonacosenoic acid and triaconthenic acid (unsaturated fatty acids may be linear or branched; And alkenyl succinic acid having the same alkenyl group; and particularly, from the viewpoint of excellent friction properties, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and various oils and fats. A linear fatty acid derived from a linear fatty acid (coconut oil fatty acid or the like) or a mixture of a linear fatty acid and a branched fatty acid synthesized by an oxo method or the like is preferably used.

Specific examples of the fatty acid ester referred to in (C-2) include polyhydric alcohol esters of the above fatty acids. Examples of the polyhydric alcohol include a polyhydric alcohol having 3 to 6 carbon atoms or a dimer or trimer thereof, and specifically, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol,
Examples thereof include polyhydric alcohols such as sorbitan, and diglycerin, ditrimethylolethane, ditrimethylolpropane, dipentaerythritol, triglycerin, tritrimethylolethane, tritrimethylolpropane, and tripentaerythritol, which are dimers and trimers thereof. Note that the ester referred to here may be a so-called full ester in which all of the hydroxyl groups in the polyhydric alcohol are esterified, or in the form of a hydroxyl group in which at least one or more of the hydroxyl groups in the polyhydric alcohol is not esterified. The remaining so-called partial ester may be used,
In the present invention, it is preferable to use a partial ester from the viewpoint of more excellent friction characteristics.

Examples of preferred compounds as fatty acid esters include glycerin monolaurate, glycerin monoisolaurate, glycerin dilaurate, glycerin diisolaurate, glycerin monomyristate, glycerin monoisomyristate, and glycerin dimyristate. , Glycerin diisomyristate, glycerin monopalmitate, glycerin monoisopalmitate, glycerin dipalmitate, glycerin diisopalmitate, glycerin monostearate, glycerin monoisostearate, glycerin distearate, glycerin diisostearate Glycerin partial esters such as glycerin monooleate, glycerin monoisooleate, glycerin dioleate, glycerin diisooleate; Ethane monolaurate, trimethylolethane monoisolaurate, trimethylolethanedilaurate, trimethylolethanediisolaurate, trimethylolethanemonomyristate, trimethylolethane monoisomyristate, trimethylolethanedimyristate, tri Methylolethane diisomyristate, trimethylolethane monopalmitate, trimethylolethane monoisopalmitate, trimethylolethane dipalmitate, trimethylolethane diisopalmitate, trimethylolethane monostearate, trimethylolethane monoisostearate Rate, trimethylolethane distearate, trimethylolethanediisostearate, trimethylolethane monooleate, trimethylolethanemo Trimethylolethane partial esters such as isooleate, trimethylolethanedioleate, and trimethylolethanediisooleate; trimethylolpropane monolaurate, trimethylolpropane monoisolaurate, trimethylolpropanedilaurate, trimethylolpropanediisolaurate , Trimethylolpropane monomyristate, trimethylolpropane monoisomyristate, trimethylolpropane dimyristate, trimethylolpropane diisomyristate, trimethylolpropane monopalmitate, trimethylolpropane monoisopalmitate, trimethylolpropanediate Palmitate, trimethylolpropane diisopalmitate,
Trimethylolpropane monostearate, trimethylolpropane monoisostearate, trimethylolpropane distearate, trimethylolpropane diisostearate, trimethylolpropane monooleate, trimethylolpropane monoisooleate, trimethylolpropanediole Trimethylolpropane partial esters such as ethate and trimethylolpropane diisooleate; pentaerythritol monolaurate, pentaerythritol monoisolaurate, pentaerythritol dilaurate, pentaerythritol diisolaurate, pentaerythritol trilaurate, pentaerythritol triisolau Rate, pentaerythritol monomyristate, pentaerythritol monoisomyristate, pen Pentaerythritol di myristate,
Pentaerythritol diisomyristate, pentaerythritol trimiristate, pentaerythritol triisomyristate, pentaerythritol monopalmitate, pentaerythritol monoisopalmitate,
Pentaerythritol dipalmitate, pentaerythritol diisopalmitate, pentaerythritol tripalmitate, pentaerythritol triisopalmitate, pentaerythritol monostearate, pentaerythritol monoisostearate, pentaerythritol distearate, pentaerythritol diisostearate Rate, pentaerythritol tristearate,
Pentaerythritol partial esters such as pentaerythritol triisostearate, pentaerythritol monooleate, pentaerythritol monoisooleate, pentaerythritol dioleate, pentaerythritol diisooleate, pentaerythritol trioleate, pentaerythritol triisooleate, etc. Sorbitan monolaurate, sorbitan monoisolaurate, sorbitan dilaurate, sorbitan diisolaurate, sorbitan trilaurate, sorbitan triisolaurate, sorbitan monomyristate, sorbitan monoisomyristate, sorbitan dimyristate, sorbitan diisomilile State, sorbitan trimyristate, sorbitan triisomyristate, sorbitan monopalmitate , Sorbitan monoisopalmitate, sorbitan dipalmitate, sorbitan diisopalmitate, sorbitan tripalmitate, sorbitan triisopalmitate, sorbitan monostearate, sorbitan monoisostearate, sorbitan distearate, sorbitan diisostearate Sorbitan partial esters such as sorbitan tristearate, sorbitan triisostearate, sorbitan monooleate, sorbitan monoisooleate, sorbitan dioleate, sorbitan diisooleate, sorbitan trioleate, sorbitan triisooleate; and These mixtures can be exemplified.

Furthermore, glycerin monooleate, glycerin dioleate, trimethylol ethane monooleate, trimethylol ethane dioleate, trimethylol propane mono oleate, trimethylol propane dioleate are particularly excellent in friction characteristics. Pentaerythritol monooleate, pentaerythritol dioleate, pentaerythritol trioleate, sorbitan monooleate, sorbitan dioleate, sorbitan trioleate and mixtures thereof are more preferably used, and furthermore, glycerin monooleate, which is monooleate. , Trimethylolethane monooleate, trimethylolpropane monooleate, pentaerythritol monooleate, sorbitan monooleate and mixtures thereof Things like are used most preferably. Further, as the fatty acid amide referred to in (C-2), specifically, the fatty acid, alkenyl succinic anhydride or acid chloride thereof may be obtained by converting ammonia, a hydrocarbon group having 1 to 8 carbon atoms or a hydrocarbon group containing a hydroxyl group. Examples thereof include amides and imides obtained by reacting a nitrogen-containing compound such as an amine compound containing only amide in the molecule.

As the nitrogen-containing compound, specifically,
Ammonia; monomethylamine, monoethylamine, monopropylamine, monobutylamine, monopentylamine, monohexylamine, monoheptylamine, monooctylamine, dimethylamine, methylethylamine, diethylamine, methylpropylamine, ethylpropylamine, dipropylamine Alkylamines such as methylbutylamine, ethylbutylamine, propylbutylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine and dioctylamine (the alkyl group may be linear or branched); monomethanolamine, monoethanolamine Amine, monopropanolamine, monobutanolamine, monopentanolamine, monohexanolamine, monoheptanolamine, monooctanol Min, mono nonanol amine,
Dimethanolamine, methanolethanolamine, diethanolamine, methanolpropanolamine, ethanolpropanolamine, dipropanolamine,
Methanol butanolamine, ethanolbutanolamine, propanolbutanolamine, dibutanolamine, dipentanolamine, dihexanolamine,
Alkanolamines such as diheptanolamine and dioctanolamine (alkanol groups may be linear or branched); and mixtures thereof.

As the fatty acid amide (C-2), specifically, lauric amide, lauric diethanolamide, lauric monopropanolamide, myristic acid amide, myristic acid diethanolamide, Myristic acid monopropanolamide, palmitic acid amide, palmitic acid diethanolamide, palmitic acid monopropanolamide, stearic acid amide, stearic acid diethanolamide, stearic acid monopropanolamide, oleic acid amide,
Oleic acid diethanolamide, oleic acid monopropanolamide, coconut oil fatty acid amide, coconut oil fatty acid diethanolamide, coconut oil fatty acid monopropanolamide, synthetic mixed fatty acid amide having 12 to 13 carbon atoms, synthetic mixed fatty acid diethanolamide having 12 to 13 carbon atoms , Synthetic mixed fatty acid monopropanolamide having 12 to 13 carbon atoms, and a mixture thereof are particularly preferably used.

On the other hand, the fatty acid metal salt referred to in (C-2) specifically includes, for example, alkaline earth metal salts (magnesium salts, calcium salts, etc.) and zinc salts of the above fatty acids. As the fatty acid metal salt of (C-2), specifically, since it is more excellent in the friction characteristics of a wet clutch,
Calcium laurate, calcium myristate, calcium palmitate, calcium stearate, calcium oleate, coconut oil fatty acid calcium, carbon number 12
~ 13 synthetic mixed fatty acid calcium, zinc laurate,
Zinc myristate, zinc palmitate, zinc stearate, zinc oleate, zinc coconut oil fatty acid, 12 to 12 carbon atoms
Thirteen synthetic zinc mixed fatty acids and mixtures thereof are particularly preferably used. Further, examples of the sulfide of the unsaturated fatty acid ester referred to in (C-2) include a reaction product of the unsaturated fatty acid ester and sulfur. (C-
As the sulfide of the unsaturated fatty acid ester of 2), a sulfide of methyl oleate is particularly preferably used from the viewpoint of superior synchro properties and friction properties of brakes. Needless to say, as the component (C), (C)
A mixture of two or more compounds having different structures selected from among friction modifiers represented by -1) and (C-2) can also be used.

When one or more components (C) arbitrarily selected in the lubricating oil composition of the present invention are used in combination, the lower limit of the content is 0.0% based on the total amount of the composition.
It is 1% by mass, preferably 0.03% by mass, while its upper limit is 5.0% by mass, preferably 3.0% by mass, based on the total amount of the composition. When the content of the component (C) is less than 0.01% by mass based on the total amount of the composition, the effect of improving the frictional characteristics by using the component (C) in combination is poor.
If the content exceeds 5.0% by mass based on the total amount of the composition, the coefficient of static friction (μ _s ) is too low, and the effectiveness of the wet brake is undesirably reduced.

Here, when the amine compound (C-1) is used as the component (C) in the present invention, the component (B) described above may be a compound of the formula (2) represented by R ⁴ , R ⁵ or R ⁶ . One or two of them, or one or two of R ⁷ , R ⁸ or R ^{9 in} the formula (3) is a hydrocarbon group having 1 to 30 carbon atoms, and the other is a hydrogen atom When an ester (or a thiophosphite) or a phosphite (or a thiophosphite), particularly a phosphite, is used in combination, the effect of improving the initial compatibility of the lubricating oil composition is particularly large. In this case, the amine compound of the component (C-1) and the above-mentioned phosphoric acid ester or phosphite of the component (B) may be added alone to the lubricating base oil, or the amine which has been reacted in advance. The compound may be added to the lubricating base oil in the form of a salt of a phosphorus compound.

The lubricating oil composition of the present invention may contain (D) a basic metal-based detergent. The basic metal-based detergent (hereinafter also referred to as a component (D)) has a high dynamic friction coefficient (μ _d ) or a low static friction coefficient required for synchronizing characteristics of a manual or automatic transmission and preventing brake squeal of tractors and construction machines. (Μ _s ). The polysulfide compound (A) according to the present invention has the effect of maintaining the dynamic friction coefficient (μ _d ) and reducing the static friction coefficient (μ _s ) even when used alone, but when used together with the component (D), The effect increases. The lower limit of the total base number of the basic metal-based detergent of the component (D) is 50 mgKOH /
g, preferably 100 mg KOH / g, while its upper limit is 450 mg KOH / g. 5 total base numbers
When the amount is less than 0 mgKOH / g, the oxidation stability of the lubricating oil composition deteriorates. On the other hand, when the total base number exceeds 450 mgKOH / g, the storage stability of the lubricating oil composition may be adversely affected. Each is not preferred. The term “total base number” as used herein refers to JIS K2501 “Petroleum products and lubricating oils-Neutralization number test method”. Means the total base number measured by the perchloric acid method in accordance with

As a specific example of the component (D), for example, (D
-1) Basic alkaline earth metal sulfonate having a total base number of 50 to 450 mg KOH / g, (D-2) Basic alkaline earth metal phenate having a total base number of 50 to 450 mg KOH / g, (D-3) All Base number is 50-450mg
One or more basic metal-based detergents selected from KOH / g basic alkaline earth metal salicylates. As the alkaline earth metal sulfonate, more specifically, for example, a molecular weight of 100 to 15
Alkaline earth metal salts of alkylaromatic sulfonic acids, particularly magnesium salts and / or calcium salts, obtained by sulfonating alkylaromatic compounds of 00, preferably 200 to 700, are preferably used. Specific examples include so-called petroleum sulfonic acid and synthetic sulfonic acid.

As the petroleum sulfonic acid, a sulfonated alkyl aromatic compound of a lubricating oil fraction of a mineral oil, a so-called mahoganic acid, which is a by-product of white oil production, is generally used. As the synthetic sulfonic acid, for example, an alkylbenzene having a linear or branched alkyl group, which is obtained as a by-product from an alkylbenzene production plant, which is a raw material of a detergent, or obtained by alkylating a polyolefin to benzene, is used as a raw material. A sulfonated product thereof, or a sulfonated product of dinonylnaphthalene is used. The sulfonating agent for sulfonating these alkyl aromatic compounds is not particularly limited, but fuming sulfuric acid or sulfuric acid is usually used. Further, as the alkaline earth metal phenate, more specifically, for example, an alkylphenol having at least one linear or branched alkyl group having 4 to 30, preferably 6 to 18 carbon atoms, and the alkylphenol and the element Alkaline earth metal salts, particularly magnesium salts and / or calcium salts, of alkylphenol sulfide obtained by reacting sulfur or Mannich reaction product of alkylphenol obtained by reacting this alkylphenol with formaldehyde are preferably used.

Further, as the alkaline earth metal salicylate, more specifically, for example, alkyl salicylic acid having at least one linear or branched alkyl group having 4 to 30 carbon atoms, preferably 6 to 18 carbon atoms. Alkaline earth metal salts, particularly magnesium salts and / or calcium salts, are preferably used. (D-1) basic alkaline earth metal sulfonate, (D-2) basic alkaline earth metal phenate and (D-3) basic alkaline earth metal salicylate have a total base number of 50 to 450 mgKOH / g
Alkyl aromatic sulfonic acid, alkyl phenol, alkyl phenol sulfide, Mannich reaction product of alkyl phenol, alkyl salicylic acid, etc., directly into alkaline earth metal oxides and hydroxides of magnesium and / or calcium, etc. Of the neutral salt (normal salt) obtained by reacting with an alkaline earth metal salt of Basic salts obtained by heating a metal salt or an alkaline earth metal base (a hydroxide or oxide of an alkaline earth metal) in the presence of water, or a neutral salt (positive salt) in the presence of carbon dioxide. Overbased salts (ultrabasic salts) obtained by reacting a salt) with a base of an alkaline earth metal. . These reactions are usually performed in a solvent (such as an aliphatic hydrocarbon solvent such as hexane, an aromatic hydrocarbon solvent such as xylene, or a light lubricating base oil).
Metal-based detergents are usually commercially available in a diluted state with a light lubricating base oil or the like, and are available.
Generally, it is desirable to use one having a metal content of 1.0 to 20% by mass, preferably 2.0 to 16% by mass.

When one or more components (D) arbitrarily selected in the lubricating oil composition of the present invention are used in combination, the lower limit of the content is 0.0% based on the total amount of the composition.
It is 5% by mass, preferably 0.1% by mass, while its upper limit is 5.0% by mass, preferably 3.0% by mass, based on the total amount of the composition. When the content of the component (D) is less than 0.05% by mass based on the total amount of the composition, the effect of improving the friction characteristics of the lubricating oil composition by using the component (D) in combination is poor.
On the other hand, if the content exceeds 5.0% by mass based on the total amount of the composition, the oxidation stability of the lubricating oil composition may be reduced and the friction material may be clogged, which is not preferable.

The lubricating oil composition of the present invention further comprises
(E) It can contain zinc thiophosphate. This switch
Zinc phosphate (hereinafter also referred to as component (E)) is an ammonium oxide.
The coefficient of static friction (μ_sReduced)
Especially effective in combination with (D) basic metal detergent
The effect is great when you do. The component (E) has static friction
Coefficient (μ _s) The effect of reducing the manual using copper alloy
Or automatic transmission synchronizer or tractor
And in the wet brake of construction equipment,
Or the tractor or building
More effectively prevent brake squeal in construction machinery.
Can be. As the zinc thiophosphate component (E),
Physically, dithiophosphoric acid represented by the following general formula (7)
Zinc and the like.

[0054]

Embedded image In the formula (7), R ²² , R ²³ , R ²⁴ and R ²⁵ each independently represent an alkyl group having 1 to 18 carbon atoms, an aryl group or an alkylaryl group having 7 to 18 carbon atoms.

As the alkyl group, specifically, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl , A tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group and an octadecyl group.
8 alkyl groups are preferred. These alkyl groups may be linear or branched. They may also be primary (primary) alkyl groups or secondary (secondary) alkyl groups.

When introducing R ²² , R ²³ , R ²⁴ and R ²⁵ , a mixture of α-olefins may be used as a raw material. In this case, the compound represented by the formula (7) has a different structure. It becomes a mixture of zinc dialkyldithiophosphates having an alkyl group. Specific examples of the aryl group include a phenyl group and a naphthyl group. As the alkylaryl group, specifically, a tolyl group, a xylyl group, an ethylphenyl group, a propylphenyl group, a butylphenyl group,
Pentylphenyl group, hexylphenyl group, heptylphenyl group, octylphenyl group, nonylphenyl group, decylphenyl group, undecylphenyl group, dodecylphenyl group and the like (these alkyl groups may be linear or branched; Including all substituted isomers).

R ²² , R ²³ , R ²⁴ and R ²⁵ may be any of such alkyl groups, aryl groups and alkylaryl groups. If the lubricating oil composition requires extreme pressure properties, (E) It is preferred to use zinc dithiophosphate having a secondary alkyl group as a component and zinc dithiophosphate having an aryl group or an alkylaryl group as a component (E) when heat resistance is required. In consideration of the above, it is most preferable to use zinc dithiophosphate having a primary alkyl group as a whole. Further, zinc dithiophosphate having a basic primary alkyl group shows particularly excellent oxidation stability, and it is effective to use it alone or in combination with another zinc dithiophosphate.

When one or more arbitrarily selected components (E) are used in combination in the lubricating oil composition of the present invention, the lower limit of the content is 0.0% based on the total amount of the composition.
It is 5% by mass, preferably 0.1% by mass, while its upper limit is 5.0% by mass, preferably 3.0% by mass, based on the total amount of the composition. When the content of the component (E) is less than 0.05% by mass based on the total amount of the composition, the effect of reducing the static friction coefficient (μ _s ) of the lubricating oil composition by the combined use of the component (E) is poor. If the amount exceeds 5.0% by mass based on the total amount of the composition, the friction material may be clogged, and the durability of the sealing material or the resin material may be adversely affected. .

The lubricating oil composition of the present invention may contain (F) a succinimide-based ashless dispersant. The combined use of a succinimide-based ashless dispersant (hereinafter also referred to as component (F)) can be expected to improve the oxidation stability and thermal stability of the composition. It also has the effect of increasing the coefficient of dynamic friction (μ _d ) between the synchronizer ring and gear cone during a gear shift operation and during the wet brake system. Specific examples of the component (F) include, for example, succinimides having at least one alkyl group or alkenyl group having 30 to 300 carbon atoms in the molecule, or derivatives thereof, and are arbitrarily selected from these. One type or two or more types can be blended. More specifically, examples of the component (F) include compounds represented by the following general formula (8) or (9).

[0060]

Embedded image In the formula (8), R ²⁶ has 30 to 300 carbon atoms, preferably 4 carbon atoms.
It represents an alkyl group or alkenyl group of 0 to 150, and e represents an integer of 1 to 5, preferably 2 to 4.

[0061]

Embedded image In the formula (9), R ²⁷ and R ²⁸ each independently have 3 carbon atoms.
It represents an alkyl or alkenyl group of 0 to 300, preferably 40 to 150, and f represents an integer of 0 to 4, preferably 1 to 3.

The succinimide is, when imidized, a so-called mono-type succinimide as shown in the general formula (8) in which succinic anhydride is added to one end of a polyamine, and succinic anhydride at both ends of the polyamine. There is a so-called bis-type succinimide represented by the general formula (2) to which is added, but as the component (F), any of them and a mixture thereof can be used. The alkyl group or alkenyl group may be linear or branched, but preferred are, specifically, propylene,
Examples thereof include a branched alkyl group and a branched alkenyl group derived from an oligomer of an olefin such as 1-butene and isobutylene, and a copolymer of ethylene and propylene. The alkyl group or alkenyl group has 30 to 30 carbon atoms.
300, preferably 40-150. When the number of carbon atoms of the alkyl group or the alkenyl group is less than 30, the solubility of the compound in the lubricating base oil is reduced. On the other hand, when the number of carbon atoms of the alkyl group or the alkenyl group exceeds 300, the lubricating oil composition has a low temperature. Since the fluidity deteriorates, each is not preferable.

The content of the succinimide-based ashless dispersant of the component (F) is arbitrary, but from the viewpoint of abrasion resistance, oxidative stability and friction characteristics, the nitrogen content thereof is usually 0.01 to 0.01.
10% by mass, preferably 0.1 to 10% by mass is desirably used. Further, as the derivative of the succinimide-based ashless dispersant of the component (F), for example, the succinimide as described above may be a monocarboxylic acid having 2 to 30 carbon atoms (such as a fatty acid), oxalic acid, phthalic acid, or tricarboxylic acid. Melitic acid,
A so-called acid-modified compound obtained by reacting a polycarboxylic acid having 2 to 30 carbon atoms such as pyromellitic acid to neutralize or amidate part or all of the remaining amino group and / or imino group; A so-called boron-modified compound in which boric acid acts on such a nitrogen-containing compound to neutralize or amidate a part or all of the remaining amino group and / or imino group; A sulfur-modified compound treated with a sulfur compound; and 2 selected from acid-, boron-, and sulfur-modified nitrogen-containing compounds as described above.
Modified compounds obtained by combining at least two kinds of modifications. Among these derivatives, boric acid-modified products are particularly excellent in the effect of improving the coefficient of friction (μ _d ). To emphasize this effect, use a boric acid-modified succinimide-based ashless dispersant. It is also effective.

When one or more components (F) arbitrarily selected in the lubricating oil composition of the present invention are used in combination, the lubricating oil composition may be used in view of abrasion resistance, oxidative stability, friction characteristics and the like.
Usually, those having a nitrogen content of 0.01 to 10% by mass, preferably 0.1 to 10% by mass are desirably used.
The lower limit of the content of the component (F) is 0.1% based on the total amount of the composition.
It is 1% by mass, preferably 0.5% by mass, while its upper limit is 15.0% by mass, preferably 10.0% by mass, based on the total amount of the composition. When the content of the component (F) is less than 0.1% by mass based on the total amount of the composition, the effect of the component (F) cannot be obtained, while the content is 1% based on the total amount of the composition.
If the content exceeds 5.0% by mass, the low-temperature fluidity of the lubricating oil composition is deteriorated, and the durability of the sealing material or the like may be adversely affected.

As described above, in the lubricating oil composition of the present invention, a specific amount of the polysulfide compound (A) is contained in the lubricating base oil so that the lubricating oil composition can be used in a manual transmission or an automatic transmission. Coefficient of friction (μ _d ) for copper alloys, which are used for synchronizer rings used in manual transmissions or automatic transmissions and wet brakes used in tractors or construction equipment when used on tractors or construction equipment And the coefficient of static friction (μ _s ) can be reduced.

Further, if necessary, one or more compounds selected from the components (B) to (F) may be used together in a specific amount to further improve the friction characteristics. That is, the lubricating oil composition of the present invention has a composition in which the component (A) is added to the lubricating base oil,
All aspects of the composition comprising various combinations of the lubricating base oil, the component (A), and the components (B) to (F) are included. Of these, a composition containing the component (B) in addition to the component (A) is particularly preferable, and the following embodiments are particularly preferable. (1) Base oil + (A) + (B), (2) Base oil + (A) + (B) + (C) or (D) or (E) or (F), (3) Base oil + (A) + (B) + (C) + (D) or (E) or (F), (4) Base oil + (A) + (B) + (C) + (D) + (E)
Or (F), (5) Base oil + (A) + (B) + (C) + (D) + (E)
+ (F), (6) Base oil + (A) + (B) + (D) + (E) or (F), (7) Base oil + (A) + (B) + (D) + ( E) +
(F). As another preferable composition, a composition containing the component (E) in addition to the component (A) is preferable, and the following embodiments are mentioned. (8) Base oil + (A) + (E), (9) Base oil + (A) + (E) + (C) or (D) or (F), (10) Base oil + (A) + (D) + (E) + (C) or (F), (11) Base oil + (A) + (C) + (D) + (E) +
(F).

In the lubricating oil composition of the present invention, for the purpose of further improving its performance, a viscosity index improver, a pour point depressant, an antioxidant, an extreme pressure additive,
Various additives such as a corrosion inhibitor, a rubber swelling agent, an antifoaming agent, and a coloring agent may be contained alone or in combination of several kinds. As the viscosity index improver, specifically, a so-called non-dispersion type viscosity index improver such as a polymer or copolymer of one or more monomers selected from various methacrylates, or a hydrogenated product thereof Or a so-called dispersion type viscosity index improver obtained by copolymerizing various methacrylic esters further containing a nitrogen compound.
Specific examples of other viscosity index improvers include non-dispersed or dispersed ethylene / α-olefin copolymers (α-olefins include propylene, 1-butene, 1-pentene, etc.), and hydrogen thereof. Compound, polyisobutylene,
Alternatively, hydrogenated products thereof, styrene-diene hydrogenated copolymers, styrene-maleic anhydride copolymers, polyalkylstyrenes and the like can be exemplified.

It is necessary to select the molecular weight of these viscosity index improvers in consideration of shear stability. Specifically, the number average molecular weight of the viscosity index improver is, for example, 5,000 in the case of the dispersion type and the non-dispersion type polymethacrylate.
１５０150,000, preferably 5,000-350,000
0 is polyisobutylene or a hydride thereof, preferably 800 to 5,000, preferably 1,000 to 4.0,
In the case where 00 is an ethylene / α-olefin copolymer or its hydride, it is preferably 800 to 150,000, more preferably 3,000 to 12,000. When an ethylene / α-olefin copolymer or a hydride thereof is used among these viscosity index improvers, a lubricating oil composition having particularly excellent shear stability can be obtained.

One or more compounds arbitrarily selected from these can be contained in an arbitrary amount. Usually, the content is 0.1 to 10% based on the total amount of the lubricating oil composition. It is preferably 40.0% by mass. As the antioxidant, any one generally used in lubricating oils such as a phenolic compound and an amine compound can be used. Specifically, alkylphenols such as 2,6-di-tert-butyl-4-methylphenol,
Methylene-4,4-bisphenol (2,6-di-te
bisphenols such as tert-butyl-4-methylphenol); naphthylamines such as phenyl-α-naphthylamine; dialkyldiphenylamines; and (3) such as (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid. , 5-di-tert-butyl-4-hydroxyphenyl) fatty acids and monohydric or polyhydric alcohols (for example, methanol, octadecanol, 1,6-hexapolysulfide, neopentyl glycol, thiodiethylene glycol, triethylene glycol, Esters with pentaerythritol). One or two or more compounds arbitrarily selected from these can be contained in an arbitrary amount. Usually, the content is 0.01 to 100% based on the total amount of the lubricating oil composition.
It is desirably 5.0% by mass.

Examples of extreme pressure additives include sulfur compounds such as disulfides and sulfurized fats and oils in addition to the polysulfide compound (A) which is an essential component of the present invention. One or two or more compounds arbitrarily selected from these can be contained in an arbitrary amount, but usually, the content is 0.01 to 5.0 based on the total amount of the lubricating oil composition. It is desirably 0% by mass. Examples of the corrosion inhibitor include benzotriazole-based, thiadiazole-based, and imidazole-based compounds.
One or more compounds arbitrarily selected from these can be contained in any amount,
Usually, the content is 0.01% based on the total amount of the lubricating oil composition.
It is desirably about 3.0% by mass. As an antifoaming agent,
For example, silicones such as dimethyl silicone and fluorosilicone are exemplified. One or two or more compounds arbitrarily selected from these can be contained in an arbitrary amount, and usually, the content is 0.001 to 0. 0 based on the total amount of the lubricating oil composition. It is desirably 0.05% by mass. The colorant can be contained in any amount, but usually the content is desirably 0.001 to 1.0% by mass based on the total amount of the lubricating oil composition.

[0071]

As described above, the lubricating oil composition of the present invention has excellent extreme pressure properties and friction characteristics, and in particular, lubricating oil for a manual or automatic transmission using a synchronizer ring, a tractor or the like. It is suitable for use as a lubricating oil for a power transmission mechanism, such as a lubricating oil for common lubrication for simultaneously lubricating a transmission and a brake used in a construction machine.

[0072]

EXAMPLES Hereinafter, the content of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[Test 1] The lubricating oil compositions shown in Table 1 were used to evaluate the frictional characteristics of copper alloys, which are materials for synchronizer rings used in manual or automatic transmissions and wet brakes used in tractors. A synchro friction test was carried out under the following conditions, and a static friction coefficient μ _s after 1000 cycles of running-in operation (μ _s indicates the maximum friction coefficient after the synchronizer ring has started to slip at 1 rpm from a stationary state) was measured.

Operating conditions for synchro friction test Synchronizer ring: Copper alloy synchronizer ring for domestic manual transmission Gear cone: Steel gear cone for domestic manual automatic transmission Oil temperature: 80 ° C. Motor rotation speed: 1200 rpm Pressing load: 400 N Pressing cycle: ON 0.5 sec / OFF 1.0 sec

[0075]

[Table 1]

1) Refined mineral oil A: kinematic viscosity 4.1 mm ² / s
(＠ 100 ° C.), paraffin-based hydrocracked mineral oil having a viscosity index of 123. 2) Lubricating oil A: Kinematic viscosity obtained by adding 20% by mass of polymethacrylate, 0.3% by mass of di-2-ethylhexyl acid phosphate ester amine salt and 0.2% by mass of thiadiazole to refined mineral oil A based on the total amount of the composition. 13.6 mm ² / s (＠
100 ° C) lubricating oil. 3) Lubricating oil B: Refined mineral oil A, based on the total amount of the composition, 20% by mass of polymethacrylate, 0.2% by mass of dibutyl phosphite, 1.2% by mass of basic primary ZnDTP, 2.0% by mass of TBN300Ca sulfonate,
Kinematic viscosity of 14.8 mm to which 0.5% by mass of alkenyl succinimide and 0.3% by mass of sorbitan monooleate are added.
² / s (@ 100 ° C) lubricating oil. 4) Polysulfide compound A: In the formula (1), R
A polysulfide compound having ^{1 to} R ³ and having 8 carbon atoms, n = 0 to 1, and x, y = 3 to 9. 5) Polysulfide compound B: In the formula (1), R
^{1 to} R ³ having 16 or 18 carbon atoms, n = 0 to 1, x, y =
1 to 9 polysulfide compounds. 6) Polysulfide compound C: In the formula (1), R
A polysulfide compound having ^{1 to} R ³ and having 4 carbon atoms, n = 0 to 1, and x, y = 2 to 13. 7) μ ₁₂₀₀ : friction coefficient at 1200 rpm after 10,000 cycles. 8) [0.5]: A polysulfide compound was added so that the sulfur content was 0.5% by mass based on the total amount of the composition.

As is evident from the results in Table 1, the lubricating oil composition of the present invention containing (A) the polysulfide compound according to the present invention is used in a synchromesh mechanism of a manual or automatic transmission or a wet brake of a tractor. high dynamic friction coefficient mu ₁₂₀₀ of a copper alloy, it is possible to prevent a decrease in the friction coefficient of the synchronous time causing gear noise in synchromesh-type manual or automatic transmission.

[0078] For Test 2] The lubricating oil composition of the present invention, in order to evaluate the influence of the frictional properties were measured static friction coefficient mu ₁ of each composition shown in Table 1 in the synchronous friction tester. The results are shown in Table 2.

Operating conditions for synchro friction test Synchronizer ring: Copper alloy synchronizer ring for domestic manual transmission Gear cone: Steel gear cone for domestic manual automatic transmission Oil temperature: 80 ° C. Motor rotation speed: 1 rpm after inertia absorption test Pressing load: 400 N Pressing cycle: ON 2.0 sec / OFF 5.0 sec

[0080]

[Table 2]

1) Refined mineral oil A: The same as refined mineral oil A in Table 1. 2) Lubricating oil A: same as lubricating oil A in Table 1. 3) Lubricating oil B: same as lubricating oil B in Table 1. 4) Polysulfide compound A: identical to polysulfide compound A in Table 1. 5) Polysulfide compound B: same as polysulfide compound B in Table 1. 6) Polysulfide compound C: identical to polysulfide compound C in Table 1. 7) μ ₁ : 1 rpm after 100 cycles after the inertial absorption test
The maximum friction coefficient of. 8) [0.5]: A polysulfide compound was added so that the sulfur content was 0.5% by mass based on the total amount of the composition.

As is evident from the results in Table 2, the lubricating oil composition of the present invention, in particular, R ^{1 to} R ³ in the formula (1)
Example 8 using a long-chain polysulfide compound B,
10 and 12 show μ ₁ which is significantly lower than the corresponding Comparative Examples 5 to 8. This means that the coefficient of friction at low sliding speeds is low, which indicates that it is effective in preventing the snagging phenomenon of the synchromesh mechanism of the manual or automatic transmission and the brake squeal of the wet brake of the tractor.

[Test 3] In order to evaluate the effect of the lubricating oil composition according to the present invention on the squealing of the tractor brake, the lubricating oil compositions of Examples 13 and 9 having the compositions shown in Table 3 were evaluated. Under the conditions shown below, a tractor brake squealing test was performed when the oil temperature was 5 ° C. and the oil temperature was the same as the outside air temperature. The results are shown in Table 3.

Tractor-brake squeal test (1) Tractor used: 15 hp tractor (2) Test method: First, tractor filled with test oil
Cool in low temperature room (0 ° C) for 2 hours or more. Accelerate the tractor out of the cold room to 30 km / h without warm air, apply full brakes, listen for sound, and measure the oil temperature. This is repeated twice to form a test at 5 ° C. Further running is repeated, and when the oil temperature reaches 30 ° C., full brake is applied and a sound is heard. This is repeated twice as a test of the outside air temperature.

[0085]

[Table 3]

1) Lubricating oil C: Refined mineral oil A: 7.5% by mass of polymethacrylate, 1.8% by mass of basic primary ZnDTP, 2.0% by mass of TBN100Ca sulfonate, 1.5% by mass of TBN300Ca sulfonate based on the total amount of the composition % And a kinematic viscosity of 9.1 mm ² / s (＠ 100 ° C.) to which 0.1% by mass of oleylamide is added. 2) Polysulfide compound B: the same as polysulfide compound B in Table 1. 3) Polysulfide compound C: the same as polysulfide compound C in Table 1. 4) [0.5]: A polysulfide compound was added so that the sulfur content was 0.5% by mass based on the total amount of the composition.

As is clear from the results in Table 3, the lubricating oil composition of the present invention (Example 13) is excellent in the effect of preventing the brake noise of the tractor.

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Claims (6)

[Claims] 1. A lubricating base oil containing a polysulfide compound represented by the following formula (1) in an amount of from 0.01 to 0.01 based on the total amount of the composition.
A lubricating oil composition comprising 10.0% by mass. Embedded image (In the formula (1), R ¹ and R ³ are an alkyl group or an alkenyl group having 6 to 30 carbon atoms, which may be the same or different, and R ² is an alkylene group having 6 to 30 carbon atoms. X and y are each independently 1 to 15, and n is 0 to 2.) 2. In the formula (1), R ¹ and R ³ have 10 carbon atoms.
An alkyl or alkenyl group to 30, R ² is a lubricating oil composition according to claim 1, characterized in that an alkylene group having 10 to 30 carbon atoms. 3. The lubricating oil composition according to claim 1, further comprising: a phosphoric ester represented by the following formula (2); a phosphite represented by the following formula (3); Lubrication characterized by comprising one or more compounds selected from derivatives of a series compound or a mixture of two or more compounds in an amount of 0.005 to 0.5% by mass of phosphorus based on the total amount of the composition. Oil composition. Embedded image (In the formula (2), R ⁴ , R ⁵ and R ⁶ are each independently:
Represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, and at least one of R ⁴ , R ⁵ and R ⁶ is a hydrocarbon group, and X ¹ , X ² , X ³ and X ⁴ are Each individually,
Indicates an oxygen atom or a sulfur atom. ) (In the formula (3), R ⁷ , R ⁸ and R ⁹ are each independently:
Represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, and at least one of R ⁷ , R ⁸ and R ⁹ is a hydrocarbon group, and X ⁵ , X ⁶ and X ⁷ are each independently , An oxygen atom or a sulfur atom. ) 4. The lubricating oil composition according to claim 1, further comprising 0.05 to 5.0% by mass of zinc dithiophosphate represented by the following formula (7) based on the total amount of the composition. A lubricating oil composition characterized by comprising: Embedded image (In the formula (7), R ²² , R ²³ , R ^24, and R ²⁵ each independently represent an alkyl group or an aryl group having 1 to 18 carbon atoms, or an alkylaryl group having 7 to 18 carbon atoms.) 5. The lubricating oil composition according to claim 1, which is a lubricating oil for a manual transmission or an automatic transmission. 6. The lubricating oil composition according to claim 1, which is a common lubricating oil for tractors and construction machines.