JP2014012855A - Lubricant oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubricant oil composition excellent in fatigue resistance such as seizure resistance and FZG micro pitching resistance, and suppressing formation of sludge in an oxidation test.SOLUTION: A lubricant oil composition contains a base oil, (A) an acidic phosphate alkyl ester having 6 to 20 carbon atoms in an alkyl group, (B) dialkyl amines and/or trialkylamines, and (C) (c-1) 0.2 to 0.6 mass% as S of a sulfur compound not containing poly sulfur bound more than -S-S-S- in the molecule and having the S content in the molecule of 15 mass% or more, and if the case may be, (c-2) 0.1 to 1.0 mass% of thiophosphoric acid tri-hydrocarbyl esters represented by a general formula (I) (R-O-)P=S (I), where R represents a hydrocarbyl group having 6 to 20 carbon atoms, and has the P content in the composition of 150 to 500 mass ppm.

Description

  The present invention relates to a lubricating oil composition, and more particularly, is a lubricating oil composition that is excellent in seizure resistance and fatigue resistance, and in which sludge generation is suppressed in an oxidation test, and particularly a speed increasing oil for wind power generation The present invention relates to a lubricating oil composition suitable as a composition.

From the viewpoint of reducing environmental impacts in recent years and the depletion of fossil fuels, wind power generation using renewable energy is expected to increase further in the future.
Wind power generation using wind power uses a propeller or other rotor that rotates in response to wind to convert wind kinetic energy into power, which drives the generator to convert it into electrical energy.
In such wind power generation, since the rotational speed of the rotor is slow, a speed increaser is used in consideration of the power generation efficiency of the generator. Various types of speed increasers are known, and planetary gear type power transmission devices are frequently used.
It has excellent seizure resistance and fatigue resistance such as FZG micropitting resistance, and oxidation stability for the speed increasing gear oil composition used for such planetary gear type power transmission devices. In the property test, the generation of sludge is required to be small.
Examples of the lubricating oil composition used in the wind power booster include (a) an extreme pressure compound containing a sulfur compound, (b) a mixture of a hydrocarbylamine compound and an alkyl phosphorothioate compound, (c) a compound for friction adjustment, and (D) A lubricating oil composition containing a base oil has been proposed (see, for example, Patent Document 1).
However, it cannot be said that this lubricating oil composition sufficiently satisfies all of the required performances required for the wind power booster oil composition.

JP 2005-126709 A

  Under such circumstances, the present invention provides a lubricating oil composition that is suitable as a speed-up gear oil composition for wind power generation that is excellent in seizure resistance and fatigue resistance and in which sludge generation is suppressed in an oxidation test. It is for the purpose.

As a result of intensive studies to develop the lubricating oil composition having the above-mentioned excellent performance, the present inventors have found that the base oil contains a specific acidic phosphoric acid alkyl ester, an alkylamine, and a specific sulfur. It has been found that a lubricating oil composition comprising a combination of compounds and containing P and S in a predetermined ratio can meet the purpose. The present invention has been completed based on such findings.
That is, the present invention
[1] Base oil, (A) alkyl phosphate alkyl ester having 6 to 20 carbon atoms, (B) dialkylamine and / or trialkylamine, and (C) (c-1) In the case where a sulfur compound having no S-S-S-S or higher polysulfur bond in the molecule and an S content in the molecule of 15% by mass or more is 0.2 to 0.6% by mass as S (C-2) General formula (I)
(R—O—) ₃ P = S (I)
(In the formula, R represents a hydrocarbyl group having 6 to 20 carbon atoms.)
A lubricating oil composition comprising 0.1 to 1.0 mass% of a thiophosphate trihydrocarbyl ester represented by the formula (1) and a P content in the composition of 150 to 500 ppm by mass. ,
[2] The above [1], wherein the component (B) is blended so that the mass ratio of [P in the component (A)] / [N in the component (B)] is 1.7 to 2.1. A lubricating oil composition according to claim 1,
[3] The lubricating oil composition according to the above [1] or [2], wherein the component (B) is a trialkylamine having 6 to 20 carbon atoms in the alkyl group,
[4] Furthermore, (D) the lubricating oil composition according to any one of [1] to [3] above, wherein 5D to 20% by mass of a partial ester of polyol, and [5] speed increase for wind power generation. The lubricating oil composition according to any one of the above [1] to [4], which is a machine oil composition,
Is to provide.

  According to the present invention, a lubricating oil composition suitable as a wind speed gearbox oil composition that is excellent in seizure resistance and fatigue resistance such as FZG micropitting resistance and has sludge generation suppressed in an oxidation test. Can be provided.

The lubricating oil composition of the present invention comprises a base oil, (A) an alkyl acid alkyl ester having 6 to 20 carbon atoms in an alkyl group, (B) a dialkylamine and / or a trialkylamine, and (C ) (C-1) A sulfur compound not containing a polysulfur bond of -SSSS or more in the molecule and having an S content of 15% by mass or more in the molecule is defined as 0.2 to 0 as S. .6 mass% and optionally (c-2) general formula (I)
(R—O—) ₃ P = S (I)
(In the formula, R represents a hydrocarbyl group having 6 to 20 carbon atoms.)
The thiophosphate trihydrocarbyl ester represented by the formula is blended in an amount of 0.1 to 1.0 mass%, and the P content in the composition is 150 to 500 mass ppm.
As the base oil used in the lubricating oil composition of the present invention, those having a kinematic viscosity at 40 ° C. in the range of 30 to 800 mm ² / s and a viscosity index of 80 or more are preferable. 40 ° C. kinematic viscosity less evaporation loss if 30 mm ² / s or more, whereas 800 mm ² / if s or less power loss due to viscosity resistance does not become too large. More preferably 40 ° C. kinematic viscosity is 32~680mm ² / s, it is preferable in particular 100 to 500 mm ² / s. If the viscosity index is 80 or more, the change in viscosity due to the change in temperature is small. This viscosity index is more preferably 100 or more, and still more preferably 130 or more.
The pour point is preferably -25 ° C or lower. If this pour point is −25 ° C. or lower, the resulting lubricating oil composition has sufficient fluidity even in a low temperature environment. This pour point is more preferably −30 ° C. or lower, and further preferably −40 ° C. or lower.
The kinematic viscosity and the viscosity index are values measured according to JIS K 2283, and the pour point is a value measured according to JIS K 2265.

There is no restriction | limiting in particular about the kind as the said base oil, Both mineral oil and synthetic oil can be used. Here, as the mineral oil, various conventionally known oils can be used, for example, paraffin-based mineral oil, intermediate-based mineral oil, naphthene-based mineral oil, and the like. Specific examples include solvent refining or hydrogen refining. Light neutral oil, medium neutral oil, heavy neutral oil, bright stock, etc. can be mentioned.
As the synthetic oil, various conventionally known oils can be used, for example, poly α-olefin, polybutene, polyol ester, dibasic acid ester, phosphoric acid ester, polyphenyl ether, alkylbenzene, alkylnaphthalene, Polyoxyalkylene glycol, neopentyl glycol, silicone oil, trimethylolpropane, pentaerythritol, hindered ester, and the like can be used. These base oils can be used alone or in combination of two or more kinds, and mineral oil and synthetic oil may be used in combination.

  In the lubricating oil composition of the present invention, the acidic phosphoric acid alkyl ester having 6 to 20 carbon atoms in the alkyl group used as the component (A) may be represented by the general formula (II)

The compound represented by these can be used.
X ¹ in the general formula (II) represents a hydrogen atom or an alkyl group having 6 to 20 carbon atoms, and X ² represents an alkyl group having 6 to 20 carbon atoms.
The alkyl group having 6 to 20 carbon atoms may be linear, branched or cyclic, and examples thereof include various hexyl groups, octyl groups, decyl groups, dodecyl groups, tetradecyl groups, hexadecyl groups, Examples include an octadecyl group and an icosyl group. Among these, an alkyl group having 10 to 18 carbon atoms is preferable.
Examples of the acidic phosphoric acid alkyl esters represented by the general formula (II) include monooctyl acid phosphate, monodecyl acid phosphate, monoisodecyl acid phosphate, monolauryl acid phosphate, mono (tridecyl) acid phosphate, and monomyristyl. Acid phosphate monoester, monopalmityl acid phosphate, monostearyl acid phosphate monophosphate, dioctyl acid phosphate, didecyl acid phosphate, diisodecyl acid phosphate, dilauryl acid phosphate, di (tridecyl) acid phosphate, dipalmityl acid Examples thereof include acidic phosphoric acid diesters such as phosphate and distearyl acid phosphate.

In the present invention, as the component (A), the acidic phosphate esters may be used alone or in combination of two or more. Moreover, the compounding quantity requires that content of all the P in a lubricating oil composition is 150-500 mass ppm. If the P content is less than 150 ppm by mass, the seizure resistance is insufficient. On the other hand, if it exceeds 500 ppm by mass, fatigue resistance (FZG micropitting resistance) decreases. The content of P is more preferably 250 to 450 mass ppm, and further preferably 350 to 400 mass ppm.
The test methods for seizure resistance and fatigue resistance are shown below.
<Seizure resistance>
(1) FZG seizure test In accordance with ASTM D 5182-91, a test is performed under the conditions of 90 ° C., 1450 rpm, and 15 minutes, and displayed on a scuffing load stage.
(2) Timken test Based on ASTM D2782, the test is performed at 800 rpm for 10 minutes, and the maximum load (lbs) that does not cause seizure is displayed.
<Fatigue resistance>
(3) FZG micropitting test In the above FZG seizure test, display is made on the micropitting generation load stage.

In the lubricating oil composition of the present invention, the dialkylamines and / or trialkylamines used as the component (B) preferably have 6 to 20 carbon atoms in the alkyl group.
Examples of dialkylamines include dihexylamine, dicyclohexylamine, dioctylamine, dilaurylamine, distearylamine, and examples of trialkylamines include trihexylamine, tricyclohexylamine, and trioctylamine. , Trilaurylamine, tristearylamine and the like.
In the lubricating oil composition of the present invention, as the component (B), the dialkylamines and trialkylamines may be used alone or in combination of two or more thereof. From the viewpoint of performance, trialkylamines are preferred. In addition, seizure resistance is reduced with monoalkylamines.
The blending amount of the component (B) is preferably selected so that the [P in the component (A)] / [N in the component (B)] mass ratio is 1.7 to 2.1. When the mass ratio is 1.7 or more, seizure resistance is good, and when the mass ratio is 2.1 or less, generation of sludge in the oxidation test is suppressed.

In the lubricating oil composition of the present invention, as the sulfur compound of component (C), (c-1) the molecule contains no S-SS-S- or higher polysulfur bond and the S content in the molecule. Is a sulfur compound of 15% by mass or more, and optionally (c-2) general formula (I)
(R—O—) ₃ P = S (I)
(In the formula, R represents a hydrocarbyl group having 6 to 20 carbon atoms.)
The thiophosphoric acid trihydrocarbyl ester represented by these is used.
In the case where the sulfur compound as the component (c-1) is a compound having a polysulfur bond of -SSSS or more in the molecule, in the Indiana oxidation test, there is a lot of sludge generation, and FZG resistance Pitching performance is reduced. Moreover, if S content in a molecule | numerator is less than 15 mass%, the addition effect of a sulfur compound will not fully be exhibited, but seizure resistance may be insufficient.
Examples of the sulfur compound of component (c-1) having such properties include the following compounds.
(1) Mono- or disulfide olefins (2) Dihydrocarbyl mono- or disulfide (3) Thiadiazole compounds (4) Dithiocarbamate compounds (5) Ester compounds having a disulfide structure (6) Other sulfur compounds

[Mono or disulfide olefin]
As the sulfurized olefin, for example, the following general formula (III)
R ¹ -S _a -R ² (III)
(In the formula, R ¹ represents an alkenyl group having 2 to 15 carbon atoms, R ² represents an alkyl group or alkenyl group having 2 to 15 carbon atoms, and a represents 1 or 2.)
The compound etc. which are represented by these can be mentioned. This compound is obtained by reacting an olefin having 2 to 15 carbon atoms or a dimer to tetramer thereof with a sulfurizing agent such as sulfur or sulfur chloride. As the olefin, propylene, isobutene, diisobutene and the like are preferable.
[Dihydrocarbyl mono or disulfide]
As dihydrocarbyl mono or disulfide, the following general formula (IV)
R ³ -S _b -R ⁴ (IV)
(In the formula, R ³ and R ⁴ are each an alkyl group having 1 to 20 carbon atoms or a cyclic alkyl group, an aryl group having 6 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, or 7 to 20 carbon atoms. An arylalkyl group, which may be the same or different from each other, and b represents 1 or 2)
It is a compound represented by these. Here, when R ³ and R ⁴ are alkyl groups, they are referred to as alkyl sulfides.
Examples of the dihydrocarbyl mono or disulfide represented by the general formula (IV) include, for example, dibenzyl mono or disulfide, various dinonyl mono or disulfide, various didodecyl mono or disulfide, various dibutyl mono or disulfide, various dioctyl mono or disulfide. , Diphenyl mono or disulfide, dicyclohexyl mono or disulfide and the like can be preferably exemplified.

[Thiadiazole compounds]
Examples of thiadiazole compounds include 2,5-bis (n-hexyldithio) -1,3,4-thiadiazole, 2,5-bis (n-octyldithio) -1,3,4-thiadiazole, 2,5 -Bis (n-nonyldithio) -1,3,4-thiadiazole, 2,5-bis (1,1,3,3-tetramethylbutyldithio) -1,3,4-thiadiazole, 3,5-bis ( n-hexyldithio) -1,2,4-thiadiazole, 3,6-bis (n-octyldithio) -1,2,4-thiadiazole, 3,5-bis (n-nonyldithio) -1,2,4 -Thiadiazole, 3,5-bis (1,1,3,3-tetramethylbutyldithio) -1,2,4-thiadiazole, 4,5-bis (n-octyldithio) -1,2,3-thiadiazole 4,5-bis n- nonyldithio) -1,2,3-thiadiazole, 4,5-bis (1,1,3,3-tetramethylbutyl dithio) -1,2,3-thiadiazoles such as can be a preferably exemplified.
[Dithiocarbamate compound]
Examples of the dithiocarbamate compound include alkylene bisdialkyldithiocarbamate, among which an alkylene group having 1 to 3 carbon atoms, a linear or branched saturated or unsaturated alkyl group having 3 to 20 carbon atoms, or a carbon number A compound having a cyclic alkyl group of 6 to 20 is preferably used. Specific examples of such dithiocarbamate compounds include methylene bisdibutyl dithiocarbamate, methylene bisdioctyl dithiocarbamate, methylene bistridecyl dithiocarbamate, and the like.

[Ester compound having a disulfide structure]
As the ester compound having a disulfide structure, the general formula (V)
^{R 5 OOC-A 1 -S-} S-A 2 -COOR 6 ··· (V)
Disulfide compounds represented by general formula (VI)
^{R 11 OOC-CR 13 R 14} -CR 15 (COOR 12) -S-S-R 20 (COOR 17) -CR 18 R 19 -COOR 16 ··· (VI)
The disulfide compound represented by these is used.
In the general formula (V), R ⁵ and R ⁶ are each independently a hydrocarbyl group having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 2 to 18 carbon atoms, particularly 3 to 3 carbon atoms. Eighteen hydrocarbyl groups are preferred. The hydrocarbyl group may be linear, branched or cyclic, and may contain an oxygen atom, a sulfur atom or a nitrogen atom. R ⁵ and R ⁶ may be the same or different, but are preferably the same for manufacturing reasons.
Next, A ¹ and A ² are each independently a group represented by CR ⁷ R ⁸ or CR ⁷ R ⁸ —CR ⁹ R ¹⁰ , and R ^{7 to} R ¹⁰ are each independently a hydrogen atom or a carbon number. 1-20 hydrocarbyl groups. The hydrocarbyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms. A ¹ and A ² may be the same or different from each other, but are preferably the same for manufacturing reasons.

On the other hand, in the general formula (VI), R ¹¹ , R ¹² , R ¹⁶ and R ¹⁷ are each independently a hydrocarbyl group having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 2 to 2 carbon atoms. A hydrocarbyl group having 18, especially 3 to 18 carbon atoms is preferred. The hydrocarbyl group may be linear, branched or cyclic, and may contain an oxygen atom, a sulfur atom or a nitrogen atom. R ¹¹ , R ¹² , R ¹⁶ and R ¹⁷ may be the same or different from each other, but are preferably the same for reasons of production.
Next, R ^{13 to} R ¹⁵ and R ^{18 to} R ²⁰ are each independently a hydrogen atom or a hydrocarbyl group having 1 to 5 carbon atoms. A hydrogen atom is preferable because the raw material is easily available.

  Specific examples of the disulfide compound represented by the general formula (V) include bis (methoxycarbonylmethyl) disulfide, bis (ethoxycarbonylmethyl) disulfide, bis (n-propoxycarbonylmethyl) disulfide, bis (isopropoxycarbonylmethyl). ) Disulfide, bis (cyclopropoxycarbonylmethyl) disulfide, 1,1-bis (1-methoxycarbonylethyl) disulfide, 1,1-bis (1-methoxycarbonyl-n-propyl) disulfide, 1,1-bis (1 -Methoxycarbonyl-n-butyl) disulfide, 1,1-bis (1-methoxycarbonyl-n-hexyl) disulfide, 1,1-bis (1-methoxycarbonyl-n-octyl) disulfide, 2,2-bis ( 2-methoxycarbonyl -N-propyl) disulfide, α, α-bis (α-methoxycarbonylbenzyl) disulfide, 1,1-bis (2-methoxycarbonylethyl) disulfide, 1,1-bis (2-ethoxycarbonylethyl) disulfide, , 1-bis (2-n-propoxycarbonylethyl) disulfide, 1,1-bis (2-isopropoxycarbonylethyl) disulfide, 1,1-bis (2-cyclopropoxycarbonylethyl) disulfide, 1,1-bis (2-methoxycarbonyl-n-propyl) disulfide, 1,1-bis (2-methoxycarbonyl-n-butyl) disulfide, 1,1-bis (2-methoxycarbonyl-n-hexyl) disulfide, 1,1- Bis (2-methoxycarbonyl-n-propyl) disulfide, 2, - bis (3-methoxycarbonyl -n- pentyl) disulfide, 1,1-bis (2-methoxycarbonyl-1-phenylethyl) and the like disulfides.

  Specific examples of the disulfide compound represented by the general formula (VI) include tetramethyl dithiomalate, tetraethyl dithiomalate, tetra-1-propyl dithiomalate, tetra-2-propyl dithiomalate, and tetra-1-butyl dithiomalate. , Tetra-2-butyl dithiomalate, tetraisobutyl dithiomalate, tetra-1-hexyl dithiomalate, tetra-1-octyl dithiomalate, tetra-1- (2-ethyl) hexyl dithiomalate, tetra-1-dithiomalate 3,5,5-trimethyl) hexyl, tetra-1-decyl dithiomalate, tetra-1-dodecyl dithiomalate, tetra-1-hexadecyl dithiomalate, tetra-1-octadecyl dithiomalate, tetrabenzyl dithiomalate, dithioapple Tetra-α- (methyl) benzyl, tetra-α, α-dimethylbenzyl dithiomalate, tetra-1- (2-methoxy) ethyl dithiomalate, tetra-1- (2-ethoxy) ethyl dithiomalate, tetra-1 dithiomalate -(2-butoxy) ethyl, tetra-1- (2-ethoxy) ethyl dithiomalate, tetra-1- (2-butoxy-butoxy) ethyl dithiomalate, tetra-1- (2-phenoxy) ethyl dithiomalate, etc. Can be mentioned.

[Other sulfur compounds]
Examples of other sulfur compounds include sulfurized fats such as sulfurized lard, sulfurized rapeseed oil, sulfurized castor oil, sulfurized soybean oil and sulfurized rice bran oil, sulfurized fatty acids such as thioglycolic acid and sulfurized oleic acid, dilauryl thiodipropionate, and distearyl. Examples thereof include dialkylthiodipropionate compounds such as thiodipropionate and dimyristylthiodipropionate, and thioterpene compounds obtained by reacting phosphorus pentasulfide with pinene.
In the lubricating oil composition of the present invention, as the sulfur compound of component (c-1), the above sulfur compounds may be used alone or in combination of two or more. Moreover, the compounding quantity of this (c-1) component requires that 0.2-0.6 mass% is contained as S in lubricating oil composition. If the S content is less than 0.2% by mass, the seizure resistance is insufficient. On the other hand, if it exceeds 0.6% by mass, the fatigue resistance such as FZG micropitting resistance is inferior, and in the Indiana oxidation test. More sludge is generated. A preferable S content is 0.3 to 0.5 mass%.
The Indiana oxidation test is performed by the following method.
<Indiana oxidation test>
In accordance with Standard's Indiana oxidation test method, air was blown at a rate of 10 liters / hour into a 300 milliliter sample at 121 ° C for 312 hours. After the experiment, the amount of sludge generated was measured in millipores. Capture with a filter and weigh.

In the lubricating oil composition of the present invention, the component (c-2) is optionally added as a general formula (I)
(R—O—) ₃ P = S (I)
The thiophosphoric acid trihydrocarbyl ester represented by these is used.
R in the general formula (I) represents a hydrocarbyl group having 6 to 20 carbon atoms. The hydrocarbyl group is a linear, branched, or cyclic alkyl group or alkenyl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. In the aryl group and aralkyl group, one or more alkyl groups may be introduced on the aromatic ring. Further, the three R—O— groups may be the same or different.
Examples of the alkyl group and alkenyl group having 6 to 20 carbon atoms include various hexyl groups, various octyl groups, various decyl groups, various dodecyl groups, various tetradecyl groups, various hexadecyl groups, various octadecyl groups, cyclohexyl groups, and various hexenyl groups. And various octenyl groups, various decenyl groups, various dodecenyl groups, various tetradecenyl groups, various hexadecenyl groups, various octadecenyl groups, and cyclohexenyl groups.
Examples of the aryl group having 6 to 20 carbon atoms include phenyl group, tolyl group, xylyl group, decylphenyl group, 2,4-didecylphenyl group, naphthyl group and the like, and examples of the aralkyl group having 7 to 20 carbon atoms include Examples include benzyl group, phenethyl group, naphthylmethyl group, methylbenzyl group, methylphenethyl group, and methylnaphthylmethyl group.
Specific examples of the thiophosphoric acid trihydrocarbyl esters represented by the general formula (I) include trihexyl thiophosphate, tri-2-ethylhexyl thiophosphate, tris (decyl) thiophosphate, trilauryl thiophosphate, trimyristylthio. Phosphate, tripalmityl thiophosphate, tristearyl thiophosphate, trioleyl thiophosphate, tricresyl thiophosphate, trixylyl thiophosphate, tris (decylphenyl) thiophosphate, tris [2,4-isoalkyl (C ₉ , C ₁₀ ) Phenyl] thiophosphate and the like. One of these thiophosphate trihydrocarbyl phosphates may be used alone, or two or more thereof may be used in combination.
In the lubricating oil composition of the present invention, the thiophosphate trihydrocarbyl esters of the component (c-2) are added as desired in order to further enhance the effect of adding the sulfur compound of the component (c-1). The amount added is preferably in the range of 0.1 to 1.0% by mass, more preferably 0.2 to 0.5% by mass, based on the total amount of the lubricating oil composition. However, the total P content in the lubricating oil composition is required to be 150 to 500 ppm by mass.

In the lubricating oil composition of the present invention, if desired, a partial ester of a polyol can be further blended as the component (D). This component (D) has an action of further suppressing sludge formation in the Indiana oxidation test.
The polyol that is a raw material for the partial ester of the polyol is not particularly limited, but is preferably an aliphatic polyol, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol, and the like. And dihydric alcohols such as triglycerides such as glycerin, trimethylolethane, and trimethylolpropane, and polyhydric alcohols such as diglycerin, triglycerin, pentaerythritol, dipentaerythritol, mannitol, and sorbit. it can.
The number of ester bonds in the partial ester is not particularly limited as long as at least one hydroxyl group remains. The hydrocarbyl group constituting the ester bond is preferably an alkyl group or alkenyl group having 6 to 20 carbon atoms. For example, various hexyl groups, octyl groups, decyl groups, dodecyl groups, tetradecyl groups, hexadecyl groups, octadecyl groups, hexenyls. Group, octenyl group, decenyl group, dodecenyl group, tetradecenyl group, hexadecenyl group, octadecenyl group and the like.
Specific examples of the partial ester of the polyol include neopentyl glycol monolaurate, neopentyl glycol monomyristate, neopentyl glycol monopalmitate, neopentyl glycol monostearate, neopentyl glycol monoisostearate, trimethylolpropane. Mono or dilaurate, trimethylolpropane mono or dimyristate, trimethylolpropane mono or dipalmitate, trimethylolpropane mono or distearate, trimethylolpropane mono or diisostearate, glycerol mono or dilaurate, glycerol mono or distearate, glycerol mono or diiso Although a stearate etc. can be mentioned, it is not limited to these.
In the lubricating oil composition of the present invention, as the component (D), a partial ester of polyol may be used alone or in combination of two or more. Moreover, the compounding quantity is about 5-20 mass% normally from the point of the suppression effect of sludge generation | occurrence | production in an Indiana oxidation test, Preferably it is about 7-15 mass%.

In the lubricating oil composition of the present invention, various additives such as an ashless detergent dispersant, an antioxidant, a rust inhibitor, a metal deactivator, a viscosity are included as long as the object of the present invention is not impaired. At least one selected from an index improver, a pour point depressant and an antifoaming agent can be blended.
Here, as the ashless detergent-dispersing agent, for example, succinimides, boron-containing succinimides, benzylamines, boron-containing benzylamines, succinic acid esters, monovalents represented by fatty acids or succinic acid or And divalent carboxylic acid amides.

  As the antioxidant, amine-based antioxidants, phenol-based antioxidants and sulfur-based antioxidants conventionally used in lubricating oils can be used. These antioxidants can be used singly or in combination of two or more. Examples of the amine antioxidant include monoalkyl diphenylamine compounds such as monooctyl diphenylamine and monononyl diphenylamine, 4,4′-dibutyldiphenylamine, 4,4′-dipentyldiphenylamine, 4,4′-dihexyldiphenylamine, 4 , 4′-diheptyldiphenylamine, 4,4′-dioctyldiphenylamine, dialkyldiphenylamine compounds such as 4,4′-dinonyldiphenylamine, polyalkyl such as tetrabutyldiphenylamine, tetrahexyldiphenylamine, tetraoctyldiphenylamine, tetranonyldiphenylamine Diphenylamine compounds, α-naphthylamine, phenyl-α-naphthylamine, butylphenyl-α-naphthylamine, pentylphenyl α- naphthylamine, hexylphenyl -α- naphthylamine, heptylphenyl -α- naphthylamine, octylphenyl -α- naphthylamine, and naphthylamine-based compounds such as nonylphenyl -α- naphthylamine.

Examples of the phenolic antioxidant include 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, and octadecyl 3- (3.5-di- monophenol compounds such as tert-butyl-4-hydroxyphenyl) propionate, 4,4′-methylenebis (2,6-di-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert- And diphenolic compounds such as butylphenol).
Examples of the sulfur-based antioxidant include 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol, phosphorus pentasulfide and Examples thereof include thioterpene compounds such as a reaction product with pinene, and dialkylthiodipropionates such as dilauryl thiodipropionate and distearyl thiodipropionate.

Examples of the rust preventive agent include metal sulfonates and succinic acid esters, and examples of the metal deactivator include benzotriazole and thiadiazole.
As the viscosity index improver, for example, polymethacrylate, dispersed polymethacrylate, olefin copolymer (for example, ethylene-propylene copolymer), dispersed olefin copolymer, styrene copolymer (for example, Styrene-diene hydrogenated copolymer, etc.).
As the pour point depressant, polymethacrylate having a weight average molecular weight of about 50,000 to 150,000 can be used.
As the antifoaming agent, a polymer silicone-based antifoaming agent and a polyacrylate-based antifoaming agent are preferable. By adding such a polymer silicone-based antifoaming agent, the defoaming property is effectively exhibited.
Examples of the polymer silicone antifoaming agent include organopolysiloxane, and fluorine-containing organopolysiloxane such as trifluoropropylmethyl silicone oil is particularly suitable.
The lubricating oil composition of the present invention is excellent in seizure resistance and fatigue resistance (FZG micropitting resistance, etc.) and generates little sludge in the oxidation test. For example, it is used as various lubricating oils such as gear oil and bearing oil. In particular, it is suitable as a lubricating oil used in a planetary gear type power transmission device used in a wind power generator.

  As described above, the present invention is a lubricating oil composition comprising a base oil, components (A) to (C), and further, these components and component (D), and usually a base oil and (A) It is a lubricating oil composition containing the component (C) and these components and the component (D).

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
The properties of the base oil used in each example and various characteristics of the lubricating oil composition obtained in each example were determined according to the following methods.
<Properties of base oil>
(1) Kinematic viscosity, viscosity index Measured according to JIS K 2283.
(2) Pour point Measured according to JIS K 2265.
<Various characteristics of lubricating oil composition>
(3) FZG seizure test A test was performed according to the method described in the specification. 13 stage pass is acceptable.
(4) Timken test A test was performed according to the method described in the specification. More than 45 lbs is acceptable.
(5) FZG micropitting test A test was performed according to the method described in the specification. Nine stage pass is acceptable.
(6) Indiana oxidation test A test was conducted according to the method described in the specification. A sludge amount of 10 or less by the Millipore filter is acceptable.

Moreover, the kind of each component used for preparation of a lubricating oil composition is as follows.
(1) Base oil: PAO, α-olefin oligomer, 40 ° C. kinematic viscosity 390 mm ² / s, viscosity index 149, pour point −50 ° C. or lower (2) Acid phosphate ester • Isodecyl: Acid phosphate (mono, di) Isodecyl ester (mixing ratio of mono and di = 1: 1)
Tridecyl: acid phosphoric acid (mono, di) tridecyl ester (mono / di mixture molar ratio = 1: 1)
Isoamyl: acid phosphoric acid (mono, di) isoamyl ester (mixing molar ratio of mono, di = 1: 1)
2-ethylhexyl: acidic phosphoric acid (mono, di) -2-ethylhexyl ester (mono / di mixed molar ratio = 1: 1)
Oleyl: acidic phosphoric acid (mono, di) oleyl ester (mono / di mixed molar ratio = 1: 1)
(3) Amines Trioctylamine Dodecylamine (4) Sulfur compounds Dithiocarbamate: Methylenebisdibutyldithiocarbamate: S content 30% by mass
Thiophosphate: Tris (2,4-diisoalkyl (C ₉ , C ₁₀ ) phenyl) thiophosphate, S content 44% by mass
・ Dibutyldithioglycolate: S content 20% by mass
Thiadiazole: 2,5-bis (1,1,3,3-tetramethylbutanedithio) -1,3,4-thiadiazole, S content 39% by mass
-Butene sulfide: containing trisulfide bond (mono, di, tri, tetrasulfide S _X : average value 2.3 of x), S content 40 mass%
(5) Polyol ester Partial ester: ester of trimethylolpropane and isostearic acid (molar ratio 1: 2)
Complete ester: ester of trimethylolpropane and isostearic acid (molar ratio 1: 3)
(6) Antioxidant A: Octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate B: 4,4′-dioctyldiphenylamine (7) Rust inhibitor: dialkylaminomethylbenzotriazole

Examples 1-8 and Comparative Examples 1-7
A lubricating oil composition having the composition shown in Table 1 was prepared, and various properties of the composition were determined. The results are shown in Table 1.

As can be seen from Table 1, in Examples 1 to 5, all of the Timken test, FZG seizure test, FZG micropitch test, and Indiana oxidation test passed. In Example 6, the polyol partial ester was not added, and in Example 7, the polyol complete ester was added. In both cases, sludge generation was slightly higher in the Indiana oxidation test. In Example 8, acidic 2-ethylhexyl phosphate having an alkyl group having 8 carbon atoms is used as the acidic phosphate, and sludge generation is slightly increased in the Indiana oxidation test.
Each of Comparative Examples 1 to 6 is out of any of the defined requirements in the present invention, and therefore the performance is inferior to that of the example.
The commercially available product (Comparative Example 7) has significantly more sludge produced in the Indiana oxidation test.

  The lubricating oil composition of the present invention is excellent in seizure resistance and FZG micropitting resistance and other fatigue resistance, and generates little sludge in an oxidation test, and various lubricating oils such as gear oil and bearing oil, especially wind power generation. It is suitable as a lubricating oil used in a speed increaser such as a planetary gear type power transmission device used in a machine.

Claims (5)

A base oil, (A) an alkyl alkyl ester having 6 to 20 carbon atoms in the alkyl group, (B) a dialkylamine and / or a trialkylamine, and (C) (c-1) in the molecule. A sulfur compound not containing polysulfur bonds of -S-S-S- or more and having an S content in the molecule of 15% by mass or more is defined as 0.2 to 0.6% by mass and optionally (c -2) General formula (I)
(R—O—) ₃ P = S (I)
(In the formula, R represents a hydrocarbyl group having 6 to 20 carbon atoms.)
A lubricating oil composition comprising 0.1 to 1.0 mass% of a thiophosphate trihydrocarbyl ester represented by the formula (1) and a P content in the composition of 150 to 500 ppm by mass. .   The lubrication according to claim 1, wherein the component (B) is blended so that the [P in the component (A)] / [N in the component (B)] mass ratio is 1.7 to 2.1. Oil composition.   The lubricating oil composition according to claim 1, wherein component (B) is a trialkylamine having 6 to 20 carbon atoms in the alkyl group.   Furthermore, the lubricating oil composition of Claim 1 formed by mix | blending 5-20 mass% of partial ester of (D) polyol.   The lubricating oil composition according to any one of claims 1 to 4, which is a speed increasing oil composition for wind power generation.