JPWO2015045816A1 - Lubricating oil composition for traction drive transmission - Google Patents

Abstract

To provide a lubricating oil composition capable of improving oxidation stability by retaining a base number, maintaining seizure resistance, preventing occurrence of precipitation due to addition of a base, and suppressing a decrease in traction coefficient. With the goal. (A) Base oil, (B) Phosphate ester compound, (C) Antioxidant and (D) An amine represented by the following general formula (I) and / or an amine oxide comprising the amine Lubricating oil composition for traction drive transmission. In general formula (I), R1 and R2 are each independently a linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, a linear, branched or cyclic group having 1 to 26 carbon atoms. An alkenyl group, (R4-0) m-H or (R5-0) n1- (R6-0) n2-H, which may be different from each other or the same; R4 to R6 each independently represents an alkylene group having 2 to 3 carbon atoms, and m, n1 and n2 each independently represents a number of 2 to 25. R3 represents a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, or a substituted or unsubstituted linear, branched or cyclic alkenyl group having 1 to 26 carbon atoms. Indicates a group.

Description

  The present invention relates to a lubricating oil composition for a traction drive transmission.

  In recent years, transmissions for automobiles such as a traction drive transmission (T-CVT) have been in the trend of an increase in transmission power capacity and a reduction in size. Tend to seek. Therefore, higher levels of oxidation stability and extreme pressure (seizure resistance) are required for lubricating oil compositions used in automobile transmissions.

  In relation to the above problem, Patent Document 1 proposes a lubricating oil composition containing an antioxidant composed of a specific hindered phenol compound. Patent Document 2 proposes a lubricating oil composition containing an acidic phosphate ester.

JP-A-6-2933892 JP 2010-202680 A

Although the lubricating oil composition of Patent Document 1 can improve the oxidative stability of the lubricating oil composition by using a hindered phenol compound, no study on seizure resistance has been conducted.
Although the lubricating oil composition of Patent Document 2 can improve the wear resistance of the lubricating oil composition with an acidic phosphate ester, no examination has been made on seizure resistance and oxidation stability. In addition, when an acidic phosphate ester is added to the lubricating oil composition, it is required to balance the lubricating oil composition by adding a base in order to suppress corrosion due to an increase in acidity. However, when the base (monoamine compound) disclosed in Patent Document 2 is added to the lubricating oil composition, the acid phosphate ester and the amine may react to cause precipitation. Moreover, the lubricating oil composition of Patent Document 2 is for machine tools, and is not described at all for automobile transmissions.

  Furthermore, the lubricating oil composition for a traction drive transmission is required to have a high traction coefficient in order to appropriately transmit power. However, the lubricating oil compositions of Patent Documents 1 and 2 have not studied at all about the balance between the traction coefficient and other performances.

As described above, a lubricating oil composition for a traction drive transmission that has improved oxidation stability, retained seizure resistance, prevented precipitation due to the addition of a base, and suppressed the decrease in traction coefficient has been proposed. It wasn't.
The present invention has been made in view of the above circumstances, and improves oxidation stability by allowing the base number to remain, maintains seizure resistance, further prevents precipitation due to the addition of a base, and has a traction coefficient. An object of the present invention is to provide a lubricating oil composition for a traction drive transmission that suppresses a decrease in the traction drive.

一般式（Ｉ）においてＲ¹及びＲ²は、それぞれ独立に、炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルキル基、炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルケニル基、（Ｒ⁴−０）_m−Ｈ又は（Ｒ⁵−０）_n1−（Ｒ⁶−０）_n2−Ｈを示し、互いに異なってもよいし、同一であっても良い。Ｒ⁴〜Ｒ⁶は、それぞれ独立に、炭素数２〜３のアルキレン基を示し、ｍ、ｎ１及びｎ２は、それぞれ独立に２〜２５の数を示す。
Ｒ³は、置換若しくは無置換の炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルキル基、又は置換若しくは無置換の炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルケニル基を示す。In order to solve the above problems, the present invention provides the following lubricating oil composition for a traction drive transmission.
1. (A) Base oil, (B) Phosphate ester compound, (C) Antioxidant and (D) An amine represented by the following general formula (I) and / or an amine oxide comprising the amine Lubricating oil composition for traction drive transmission.

In the general formula (I), R ¹ and R ² are each independently a linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, a linear or branched alkyl group having 1 to 26 carbon atoms, or cyclic alkenyl group, (R ⁴ -0) _m -H, or _{^{(R 5 -0) n1 - (}} R 6 -0) indicates _n2 -H, may be different from each other, it may be the same. R ^{4 to} R ⁶ each independently represents an alkylene group having 2 to 3 carbon atoms, and m, n1 and n2 each independently represents a number of 2 to 25.
R ³ is a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, or a substituted or unsubstituted linear, branched or cyclic group having 1 to 26 carbon atoms. An alkenyl group is shown.

  The lubricating oil composition for a traction drive transmission according to the present invention maintains seizure resistance while improving oxidation stability by allowing the base number to remain, prevents occurrence of precipitation due to addition of a base, and has a traction coefficient. Reduction can be suppressed.

The lubricating oil composition for a traction drive transmission of the present invention comprises (A) a base oil, (B) a phosphoric ester compound, (C) an antioxidant and (D) an amine represented by the general formula (I) and / or Alternatively, an amine oxide composed of the amine is blended.
In the present invention, for example, “(A) base oil, (B) phosphate ester compound, (C) antioxidant and (D) amine represented by general formula (I) or amine oxide composed of the amine” The composition defined as “a lubricating oil composition” is not limited to “a composition containing the components (A) to (D)”, but instead of at least one of the components (A) to (D). In addition, “a composition containing a modified product in which the component is modified” and “a composition containing a reaction product in which at least some of the components (A) to (D) react with each other” are also included.

Hereinafter, the “lubricating oil composition for traction drive transmission of the present invention” may be referred to as “lubricating oil composition”.
[Component A: Base oil]
Mineral oil and / or synthetic oil is used as the base oil in the lubricating oil composition.
Mineral oils include paraffinic mineral oils, intermediate mineral oils and naphthenic mineral oils obtained by conventional refining methods such as solvent refining and hydrogenation refining, or waxes produced by the Fischer-Tropsch process (gas-liquid liquid wax). And those produced by isomerizing mineral oil wax.

Examples of synthetic oils include hydrocarbon synthetic oils and ether synthetic oils.
Examples of the hydrocarbon synthetic oil include polybutenes, polyisobutylenes, 1-octene oligomers, 1-decene oligomers, α-olefin oligomers such as ethylene-propylene copolymers or hydrides thereof, and aromatic series such as alkylbenzenes and alkylnaphthalenes. Compound, compound having one naphthene ring such as cyclopentane, cyclohexane, phychite, oleanane, 2,4-dicyclohexyl-2methylpentane, bicyclo [2.2.1] heptane, bicyclo [2.2.1] heptane ring Dimer hydrides of compounds, octahydromethanonaphthalene, octahydromethanoindane, naphthene ring-containing compounds such as compounds having two or more naphthene rings such as decahydromethanoazulene, and compounds having one naphthene ring and 2 naphthenic rings The compounds having above include compounds is an alkyl or alkylene group having 1 to 3 carbon atoms are substituted one or more. In the case of a bridged ring hydrocarbon, the number of naphthene rings is 2 in the case of bicyclic systems, and the number of naphthene rings is 3 in the case of tricyclic systems.
Examples of ether synthetic oils include polyoxyalkylene glycol and polyphenyl ether.
As the base oil, only one kind of the mineral oil and / or the synthetic oil may be used, but two or more kinds may be used. Further, one or more mineral oils and one or more synthetic oils may be used in combination.

Among the above-mentioned base oils, from the viewpoint of increasing the traction coefficient, naphthenic mineral oils or naphthenic ring-containing compounds (naphthenic synthetic oils) are preferable, of which naphthenic synthetic oils are more preferable, and of these, two naphthenic rings are included. The naphthenic synthetic oil having the above is more preferable.
Also, among naphthenic synthetic oils having two or more naphthene rings, bicyclo [2.2.1] heptane, bicyclo [2.2.1] heptane ring compound dimer or trimer hydride is preferable. In particular, a dimer is preferable.

  The bicyclo [2.2.1] heptane ring compound is a compound having a bicyclo [2.2.1] heptane ring and optionally substituted with one or more alkyl groups having 1 to 3 carbon atoms. And those having a molecular weight of 200 to 500. As a dimer of the compound, endo-2-methyl-exo-3-methyl-exo-2-[(exo-3-methylbicyclo [2.2.1] hept-exo-2-yl) methyl] Bicyclo [2.2.1] heptane, endo-2-methyl-exo-3-methyl-exo-2-[(exo-2-methylbicyclo [2.2.1] hept-exo-3-yl) methyl ] Bicyclo [2.2.1] heptane, endo-2-methyl-exo-3-methyl-exo-2-[(endo-3-methylbicyclo [2.2.1] hept-endo-2-yl) Methyl] bicyclo [2.2.1] heptane and endo-2-methyl-exo-3-methyl-exo-2-[(endo-2-methylbicyclo [2.2.1] hept-endo-3-yl ) Methyl] Bisiku [2.2.1] heptane, and the like. As a trimer of the compound, 3-methyl-2-[(3-methylbicyclo [2.2.1] hept-2-yl) methyl] -2-[(2,3-dimethylbicyclo [ 2.2.1] Hept-2-yl) methyl] bicyclo [2.2.1] heptane, 2-[(bicyclo [2.2.1] hept-2-yl) methyl] -2-[(2 -Methylbicyclo [2.2.1] hept-2-yl) methyl] bicyclo [2.2.1] heptane, 2-[(bicyclo [2.2.1] hept-2-yl) ethyl] -2 -[(2-ethylbicyclo [2.2.1] hept-2-yl) ethyl] bicyclo [2.2.1] heptane and the like.

  The blending amount of the base oil which is the component (A) in the total amount of the lubricating oil composition is preferably 80 to 99% by mass from the viewpoint of maintaining a high traction coefficient while ensuring the blending ratio of the other components. 90 to 95% by mass is more preferable.

[Component B: Phosphate ester compound]
In the present invention, a phosphate ester compound is used as the B component. The phosphate ester compound has a role of maintaining seizure resistance.
Examples of phosphoric acid ester compounds include phosphoric acid esters such as orthophosphoric acid esters, acidic phosphoric acid esters, and phosphorous acid esters, and at least one of these can be used. Among these phosphate esters, phosphite esters are suitable, but can be appropriately selected according to the purpose.

一般式（II）において、Ｒ⁷〜Ｒ⁹は、炭素数４〜２４のアルキル基、炭素数４〜２４のアルケニル基並びに前記アルキル基又はアルケニル基中に酸素原子、窒素原子及び硫黄原子から選ばれる原子を含有してなる炭素数４〜２４のヘテロ原子含有基を示す。
Ｒ⁷〜Ｒ⁹のアルキル基及びアルケニル基は、直鎖状、分岐状、環状のいずれであってもよいが、直鎖状であることが好ましい。さらに、Ｒ⁷〜Ｒ⁹のアルキル基及びアルケニル基は、好ましくは炭素数６〜２０であり、より好ましくは炭素数７である。
Ｒ⁷〜Ｒ⁹がヘテロ原子含有基である場合、ヘテロ原子の数は１〜４が好ましく、ヘテロ原子は硫黄原子であることが好ましい。As the normal phosphate, for example, those represented by the following general formula (II) are used.

In the general formula (II), R ^{7 to} R ⁹ are selected from an alkyl group having 4 to 24 carbon atoms, an alkenyl group having 4 to 24 carbon atoms, and an oxygen atom, a nitrogen atom, and a sulfur atom in the alkyl group or alkenyl group. A heteroatom-containing group having 4 to 24 carbon atoms, which contains the above atoms.
The alkyl group and alkenyl group of R ^{7 to} R ⁹ may be linear, branched or cyclic, but is preferably linear. Furthermore, the alkyl group and alkenyl group of R ^{7 to} R ⁹ preferably have 6 to 20 carbon atoms, and more preferably 7 carbon atoms.
When R ^{7 to} R ⁹ are heteroatom-containing groups, the number of heteroatoms is preferably 1 to 4, and the heteroatoms are preferably sulfur atoms.

As the alkyl group in R ^{7 to} R ⁹ , an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an icosyl group, Examples include a heicosyl group, a docosyl group, a tricosyl group, and a tetracosyl group, which may be linear, branched, or cyclic. The alkenyl group includes octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, icocenyl, heicosenyl, dococenyl Group, tricocenyl group and tetracocenyl group may be mentioned, and these may be linear, branched or cyclic, and the position of the double bond is also arbitrary.

一般式（III）において、Ｒ¹⁰は、水素原子、炭素数４〜２４のアルキル基、炭素数４〜２４のアルケニル基並びに前記アルキル基又はアルケニル基中に酸素原子、窒素原子及び硫黄原子から選ばれる原子を含有してなる炭素数４〜２４のヘテロ原子含有基を示すが、これらのうちではアルキル基、アルケニル基又はヘテロ原子含有基であることが好ましい。また、Ｒ¹¹は、炭素数４〜２４のアルキル基、炭素数４〜２４のアルケニル基並びに前記アルキル基又はアルケニル基中に酸素原子、窒素原子及び硫黄原子から選ばれる原子を含有してなる炭素数４〜２４のヘテロ原子含有基を示す。
Ｒ¹⁰及びＲ¹¹のアルキル基及びアルケニル基は、直鎖状、分岐状、環状のいずれであってもよいが、直鎖状であることが好ましい。さらに、Ｒ¹⁰及びＲ¹¹のアルキル基及びアルケニル基は、好ましくは炭素数６〜２０である。
Ｒ¹⁰及びＲ¹¹のアルキル基及びアルケニル基の具体例は、Ｒ⁷〜Ｒ⁹と同様である。
Ｒ¹⁰及びＲ¹¹がヘテロ原子含有基である場合、ヘテロ原子の数は１〜４が好ましく、ヘテロ原子は硫黄原子であることが好ましい。As acidic phosphoric acid ester, what is shown by the following general formula (III) is used, for example.

In the general formula (III), R ¹⁰ is selected from a hydrogen atom, an alkyl group having 4 to 24 carbon atoms, an alkenyl group having 4 to 24 carbon atoms, and an oxygen atom, a nitrogen atom and a sulfur atom in the alkyl group or alkenyl group. A heteroatom-containing group having 4 to 24 carbon atoms and containing an atom is preferable. Among these, an alkyl group, an alkenyl group or a heteroatom-containing group is preferable. R ¹¹ is a carbon containing an alkyl group having 4 to 24 carbon atoms, an alkenyl group having 4 to 24 carbon atoms, and an atom selected from an oxygen atom, a nitrogen atom and a sulfur atom in the alkyl group or alkenyl group. The hetero atom containing group of number 4-24 is shown.
The alkyl group and alkenyl group of R ¹⁰ and R ¹¹ may be linear, branched or cyclic, but is preferably linear. Furthermore, the alkyl group and alkenyl group of R ¹⁰ and R ¹¹ preferably have 6 to 20 carbon atoms.
Specific examples of the alkyl group and alkenyl group for R ¹⁰ and R ¹¹ are the same as those for R ^{7 to} R ⁹ .
When R ¹⁰ and R ¹¹ are heteroatom-containing groups, the number of heteroatoms is preferably 1 to 4, and the heteroatoms are preferably sulfur atoms.

一般式（IV）において、Ｒ¹²は、水素原子、炭素数４〜２４のアルキル基、炭素数４〜２４のアルケニル基並びに前記アルキル基又はアルケニル基中に酸素原子、窒素原子及び硫黄原子から選ばれる原子を含有してなる炭素数４〜２４のヘテロ原子含有基を示すが、これらのうちではアルキル基、アルケニル基又はヘテロ原子含有基であることが好ましい。また、Ｒ¹³は、炭素数４〜２４のアルキル基、炭素数４〜２４のアルケニル基並びに前記アルキル基又はアルケニル基中に酸素原子、窒素原子及び硫黄原子から選ばれる原子を含有してなる炭素数４〜２４のヘテロ原子含有基を示す。
Ｒ¹²及びＲ¹³のアルキル基及びアルケニル基は、直鎖状、分岐状、環状のいずれであってもよいが、直鎖状であることが好ましい。さらに、Ｒ¹²及びＲ¹³のアルキル基及びアルケニル基は、好ましくは炭素数６〜２０であるが、より好ましくは炭素数６〜１２である。
Ｒ¹²及びＲ¹³がヘテロ原子含有基である場合、ヘテロ原子の数は１〜４が好ましく、ヘテロ原子は硫黄原子であることが好ましい。
Ｒ¹²及びＲ¹³のアルキル基及びアルケニル基の具体例は、Ｒ⁷〜Ｒ⁹と同様である。As the phosphite, for example, those represented by the following general formula (IV) are used.

In the general formula (IV), R ¹² is selected from a hydrogen atom, an alkyl group having 4 to 24 carbon atoms, an alkenyl group having 4 to 24 carbon atoms, and an oxygen atom, a nitrogen atom and a sulfur atom in the alkyl group or alkenyl group. A heteroatom-containing group having 4 to 24 carbon atoms and containing an atom is preferable. Among these, an alkyl group, an alkenyl group or a heteroatom-containing group is preferable. R ¹³ is an alkyl group having 4 to 24 carbon atoms, an alkenyl group having 4 to 24 carbon atoms, and a carbon containing an atom selected from an oxygen atom, a nitrogen atom and a sulfur atom in the alkyl group or alkenyl group. The hetero atom containing group of number 4-24 is shown.
The alkyl group and alkenyl group of R ¹² and R ¹³ may be linear, branched or cyclic, but is preferably linear. Furthermore, the alkyl group and alkenyl group of R ¹² and R ¹³ preferably have 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms.
When R ¹² and R ¹³ are heteroatom-containing groups, the number of heteroatoms is preferably 1 to 4, and the heteroatoms are preferably sulfur atoms.
Specific examples of the alkyl group and alkenyl group for R ¹² and R ¹³ are the same as those for R ^{7 to} R ⁹ .

  The blending amount of the phosphoric acid ester compound of component B is preferably 0.05 to 10% by mass with respect to the total amount of the lubricating oil composition from the viewpoint of improving seizure resistance and suppressing the reduction of the traction coefficient. More preferably, it is 0.5-8 mass%.

[C component: antioxidant]
In the present invention, an antioxidant is used as the C component. Examples of the antioxidant include amine-based antioxidants, phenol-based antioxidants, and sulfur-based antioxidants.
Examples of amine-based antioxidants include dialkyl (alkyl group having 1 to 20 carbon atoms) diphenylamine, phenyl such as 4,4′-dibutyldiphenylamine, 4,4′-dioctyldiphenylamine, and 4,4′-dinonyldiphenylamine. And naphthylamines such as -α-naphthylamine, octylphenyl-α-naphthylamine, and nonylphenyl-α-naphthylamine.

  Examples of the phenolic antioxidant include monophenolic antioxidants such as 2,6-di-tert-butyl-4-methylphenol and 2,6-di-tert-butyl-4-ethylphenol, Examples thereof include diphenol antioxidants such as 4′-methylenebis (2,6-di-tert-butylphenol) and 2,2′-methylenebis (4-ethyl-6-tert-butylphenol).

Examples of the sulfur-based antioxidant include phenothiazine, pentaerythritol-tetrakis- (3-laurylthiopropionate), bis (3,5-tert-butyl-4-hydroxybenzyl) sulfide, thiodiethylenebis (3- (3,5-di-tert-butyl-4-hydroxyphenyl)) propionate, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazine-2 -Methylamino) phenol and the like.
The antioxidant mentioned above may be used individually by 1 type, and may be used in combination of 2 or more type. In the present invention, it is preferable to use a combination of a phenol-based antioxidant and an amine-based antioxidant or a sulfur-based antioxidant, and a combination of a phenol-based antioxidant and an amine-based antioxidant is optimal. .

  The blending amount of the antioxidant of component C is 0.1 to 1.6% by mass with respect to the total amount of the lubricating oil composition from the viewpoint of improving the oxidation stability and suppressing the decrease in the traction coefficient. Preferably, it is 0.5-1 mass%.

一般式（Ｉ）においてＲ¹及びＲ²は、それぞれ独立に、炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルキル基、炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルケニル基、（Ｒ⁴−０）_m−Ｈ又は（Ｒ⁵−０）_n1−（Ｒ⁶−０）_n2−Ｈを示し、互いに異なってもよいし、同一であっても良い。Ｒ⁴〜Ｒ⁶は、それぞれ独立に、炭素数２〜３のアルキレン基を示し、ｍ、ｎ１及びｎ２は、それぞれ独立に２〜２５の数を示す。
Ｒ³は、置換若しくは無置換の炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルキル基、又は置換若しくは無置換の炭素数１〜２６の直鎖状、分岐状、若しくは環状のアルケニル基を示す。[D component: amine]
In the present invention, the amine represented by the general formula (I) and / or amine oxide of the amine (hereinafter sometimes referred to as “amine of D component”) is used as the D component. Both the amine represented by the general formula (I) and the amine oxide of the amine can achieve the effects of the present invention. However, from the viewpoint of easily maintaining the base number and maintaining oxidation stability, the general formula (I) The amines shown are preferred.

In the general formula (I), R ¹ and R ² are each independently a linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, a linear or branched alkyl group having 1 to 26 carbon atoms, or cyclic alkenyl group, (R ⁴ -0) _m -H, or _{^{(R 5 -0) n1 - (}} R 6 -0) indicates _n2 -H, may be different from each other, it may be the same. R ^{4 to} R ⁶ each independently represents an alkylene group having 2 to 3 carbon atoms, and m, n1 and n2 each independently represents a number of 2 to 25.
R ³ is a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, or a substituted or unsubstituted linear, branched or cyclic group having 1 to 26 carbon atoms. An alkenyl group is shown.

  The D component amine neutralizes the acidity increased by the addition of the B component phosphoric acid ester compound, suppresses corrosion of the metal, suppresses oxidation of the lubricating oil composition, and improves oxidation stability. Have a role to play. As other basic substances, metallic detergents, primary amines and secondary amines can be considered. However, the metal detergent is too reactive, and the effect of maintaining the seizure resistance of the phosphoric acid ester compound of the B component is impaired. Moreover, a primary amine and a secondary amine may react with a phosphate ester type compound to cause precipitation.

In general formula (I), R ^{1 to} R ³ are preferably alkyl groups, more preferably unsubstituted and linear alkyl groups, from the viewpoint of improving stability.
Further, in formula (I), it is preferable that the total number of carbon atoms of R ¹ to R ³ is 10 to 40, more preferably from 11 to 23, more preferably from 12 to 22. By setting the total number of carbons to 10 or more, the amine of component D can remain as an active ingredient for a long period of time, and by setting the total number of carbons to 40 or less, basic active ingredients can be added at a certain ratio. It can ensure and can suppress the addition amount of the amine of D component.
Further, in formula (I), preferably two single addition of R ¹ and R ² is a methyl group, and more preferably both R ¹ and R ² are methyl groups. From the viewpoint of improving stability, R ³ is preferably a linear alkyl group having 8 to 22 carbon atoms having no substituent, and a linear alkyl group having 10 to 20 carbon atoms having no substituent. Groups are more preferred.
Only 1 type may be used for the amine of D component, and 2 or more types may be mixed and used for it.

  The amine of the D component preferably has a base number that reduces the blending amount of the D component from the viewpoint of suppressing a decrease in the traction coefficient, and preferably has a base number of 50 mgKOH / g or more, more preferably 100 mgKOH / g or more. . In the present invention, the base number means a value measured by the hydrochloric acid method of JIS K2501.

The compounding amount of the amine of component D is preferably 0.05 to 4% by mass with respect to the total amount of the lubricating oil composition from the viewpoint of appropriate neutralization and suppression of reduction in the traction coefficient. It is more preferable that it is 0.8 mass%, and 0.15-0.5 mass% is still more preferable.
In the lubricating oil composition, the B-component phosphate ester compound and the D-component amine are preferably blended in a mass ratio of 35: 1 to 2: 1, and a mass of 20: 1 to 3: 1. It is more preferable to mix by ratio. By blending at such a mass ratio, the balance between seizure resistance and corrosion inhibition can be improved.

[E component: lubricating oil additive]
In the lubricating oil composition of the present invention, a lubricating oil additive can be further blended as the E component in the composition obtained by blending the A to D components.
Examples of the lubricating oil additive for component E include viscosity index improvers, friction modifiers and other lubricating oil additives, and one or more lubricating oil additives selected from these are blended. It is preferable.

As a friction modifier, the partial ester compound obtained by reaction with a fatty acid and aliphatic polyhydric alcohol is mentioned. In the partial ester compound, the fatty acid is preferably a fatty acid having a linear or branched hydrocarbon group having 6 to 30 carbon atoms, and the hydrocarbon group has more preferably 8 to 24 carbon atoms, particularly preferably 10 to 10 carbon atoms. 20. Examples of fatty acids include saturated fatty acids such as caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, and lignoceric acid, myristoleic acid, palmitoleic acid, oleic acid, and Examples include unsaturated fatty acids such as linolenic acid, preferably oleic acid. The aliphatic polyhydric alcohol is a divalent to hexavalent alcohol, and examples thereof include ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, sorbitan, and the like, and sorbitan is preferable. These partial ester compounds may be used individually by 1 type, and may be used in combination of 2 types.
Also, aliphatic saturated monoamines and unsaturated monoamines having about 10 to 20 carbon atoms such as stearylamine and oleylamine can be suitably used as friction modifiers.

  Examples of other lubricating oil additives include antifoaming agents, metal deactivators, oil absorbers, ultraviolet absorbers, rust inhibitors, and pour point depressants. Examples of the antifoaming agent include silicone oil and fluorinated silicone oil. Examples of the metal deactivator include N- [N, N′-dialkyl (an alkyl group having 3 to 12 carbon atoms). And copper deactivator such as aminomethyl] triazole.

The blending amount of the above-mentioned lubricating oil additive varies depending on the performance to be added, so it cannot be said unconditionally, but it is preferably 3% by mass or less, and preferably 0.1 to 1% by mass with respect to the total amount of the lubricating oil composition. It is more preferable that
The lubricating oil composition preferably contains substantially no primary or secondary aliphatic amine. “Substantially not contained” means 0.1 mass% or less, preferably 0.01 mass% or less, more preferably 0 mass%, based on the total amount of the lubricating oil composition. In addition, you may add a primary or secondary amine in the range which does not impair the effect of this invention. For example, if it is a primary amine or a secondary amine having a total carbon number exceeding 20, although it depends on the type of the base oil, it tends to hardly cause a precipitate.

[Traction drive transmission]
The traction drive transmission of the present invention uses the above-described lubricating oil composition for a traction drive transmission of the present invention as a lubricating oil composition contained in the traction drive transmission.
A conventionally known traction drive transmission main body can be used. As the lubricating oil composition contained in the traction drive transmission, the above-described lubricating oil composition for a traction drive transmission of the present invention is used.
The traction drive transmission of the present invention has sufficient oxidation stability due to excellent base number persistence, maintains seizure resistance, has no obstacles due to precipitates, has a high traction coefficient, and is excellent in power transmission. Is.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples. In the examples, the lubricating oil composition was evaluated and measured as follows. The results are shown in Tables 1 and 2.

<Evaluation method and measurement method of lubricating oil composition>
(1) Base Number Based on JIS K2501, the base number of the lubricating oil composition (new oil) was measured by the hydrochloric acid method.
(2) Seizure resistance In the Falex test (rotation speed: 290 rpm, oil temperature 100 ° C.) based on ASTM D3233 (Method A), the load (N) when the test piece was seized was measured. The larger the load, the better the seizure resistance. In addition, what was not seized even with the load 13340N was described as ">13340".

(3) Residual base number amount Based on CEC L-48-A-00 [B], the base number of a lubricating oil composition subjected to an oxidation stability test at 150 ° C. for 240 hours was compliant with JIS K2501. Then, it was measured by the hydrochloric acid method.

(4) Appearance The appearance of the lubricating oil composition (new oil) immediately after blending was visually observed. “◯” indicates that no change in appearance was observed, “Δ” indicates cloudiness, and “x” indicates precipitation.

(5) Traction coefficient The traction coefficient at 100 ° C was measured with a two-cylinder friction tester. That is, one of the cylinders of the same size in contact (diameter 40 mm, thickness 20 mm, driven type is a flat type with a curvature radius of 20 mm, and the driving side is a flat type without crowning) is continuously constant at the other rotation speed. The tangential force generated between the two cylinders, that is, the traction force, was measured by applying a weight of 147.1 N to the contact portion of both cylinders with a weight, and the traction coefficient was obtained. This cylinder was made of mirror-finished chromium-molybdenum steel SCM420, the average peripheral speed was 6.8 m / s, and the maximum Hertz contact pressure was 1.24 GPa. The traction coefficient was measured under the condition that the slip ratio was 5%.
(6) μ decrease rate Based on the traction coefficient obtained as described above, the decrease rate of the traction coefficient of each example and the comparative example with respect to the traction coefficient of the comparative example 1 was calculated.

[Examples 1 to 18 and Comparative Examples 1 to 15]
The materials shown in Table 1 and Table 2 were blended and stirred at 80 ° C. for 30 minutes to prepare a lubricating oil composition, and the above evaluation and measurement were performed.
In addition, the raw material symbol used in Table 1 and Table 2 shows the following.

(Component A)
A-1: A naphthenic synthetic oil (a dimer hydride of a bicyclo [2.2.1] heptane ring compound) (endo-2-methyl-exo-3-methyl-exo-2-[(exo-3 -Methylbicyclo [2.2.1] hept-exo-2-yl) methyl] bicyclo [2.2.1] heptane and endo-2-methyl-exo-3-methyl-exo-2-[(exo 2-Methylbicyclo [2.2.1] hept-exo-3-yl) methyl] bicyclo [2.2.1] heptane) (number of naphthene rings: 4)
A-2: Naphthenic synthetic oil (2,4-dicyclohexyl-2methylpentane) (Number of naphthene rings: 2)
A-3: Naphthenic synthetic oil ((1S, 3aR, 4S, 8aS) -4,8,8-trimethyl-9-methylene-decahydro-1,4-methanoazulene)
A-4: Ester-based synthetic oil (3,5,5-trimethylhexanoic acid 3,5,5-trimethylhexyl ester)
(B component)
Phosphate ester compound (phosphorus content 920 ppm, total acid value 1.95 mg KOH / g).

(C component)
C-1: Monobutylphenyl monooctylphenylamine C-2: Pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]
C-3: benzenepropanoic acid, 3,5-bis (1,1-dimethyl-ethyl) -4-hydroxy-C7-C9 side chain alkyl ester C-4: 2,6-di-tert-butyl-4- Methylphenol C-5: phenyl-1-naphthylamine C-6: bis (tridecyl) thiodipropionate
(D component)
D-1: N-methyldioleilamine (total carbon number of R ^{1 to} R ³ of general formula (I): 37, base number 107 mgKOH / g)
D-2: N-methyldidecylamine (total carbon number of R ^{1 to} R ³ of general formula (I), base number 184 mgKOH / g)
D-3: Dimethyldodecylamine (total carbon number of R ^{1 to} R ³ of general formula (I) 14, base number 261 mg KOH / g)
D-4: Trioctylamine (total carbon number of R ^{1 to} R ³ of general formula (I) 24, base number 154 mgKOH / g)
D-5: Dicyclohexylmethylamine (total carbon number of R ^{1 to} R ³ of general formula (I) 13, base number 297 mgKOH / g)
D-6: N, N-dimethyloctylamine (total carbon number of R ^{1 to} R ³ of general formula (I), base number 327 mgKOH / g)

(E component)
E-1: detergent dispersant (long-chain calcium alkylsulfonate)
E-2: detergent dispersant (polyolefin polyamine succinimide / polyol)
E-3: detergent dispersant (long chain calcium salicylate)
E-4: Friction modifier (8: 2: 1 mixture of long chain alkyl polyamide, thioalkyl long chain alkyl ester and oleic acid monoglyceride)
E-5: Antifoaming agent (fluorinated silicone)
E-6: Benzotriazole UV absorber (aliphatic primary amine or secondary amine)
F-1: Oleylamine (aliphatic primary amine)
F-2: Di-cured beef tallow alkylamine (12 to 20 carbon atoms of each alkyl group, C16: 30%, C18: 64%) (aliphatic secondary amine)

From Tables 1 and 2, the following can be understood. The lubricating oil compositions of the examples were able to retain a sufficient base number even after being used for a long time in a high temperature environment. This means that a base is always present even in use under severe conditions, and oxidation stability is good. Further, the lubricating oil compositions of the examples were able to maintain seizure resistance without causing seizure even at a load of 13340 N, and did not cause precipitation due to the addition of a base. In addition, the lubricating oil compositions of the examples had little decrease in traction coefficient with respect to Comparative Example 1 as a reference, and could suppress the decrease in traction coefficient.
On the other hand, the lubricating oil compositions of Comparative Examples 1 to 7, 9 to 10, and 12 to 15 cannot sufficiently retain the base number after being used for a long time in a high temperature environment. This means that when used under severe conditions, the amount of base is not sufficient and the oxidation stability cannot be satisfied. In Comparative Examples 7 and 8, precipitation was caused by using a primary amine or a secondary amine. Moreover, since the comparative examples 9-11 used the metal type | system | group detergent dispersing agent, the effect which maintains the seizure resistance of the phosphate ester type compound of B component was impaired.

  According to the present invention, a lubricating oil that improves oxidation stability by retaining the base number, maintains seizure resistance, prevents precipitation due to addition of a base, and suppresses a decrease in traction coefficient. A composition can be provided. Therefore, it can be effectively used as a lubricating oil composition for a traction drive transmission (T-CVT).

Claims (6)

(A) Base oil, (B) Phosphate ester compound, (C) Antioxidant and (D) An amine represented by the following general formula (I) and / or an amine oxide comprising the amine Lubricating oil composition for traction drive transmission.

In the general formula (I), R ¹ and R ² are each independently a linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, a linear or branched alkyl group having 1 to 26 carbon atoms, or cyclic alkenyl group, (R ⁴ -0) _m -H, or _{^{(R 5 -0) n1 - (}} R 6 -0) indicates _n2 -H, may be different from each other, it may be the same. R ^{4 to} R ⁶ each independently represents an alkylene group having 2 to 3 carbon atoms, and m, n1 and n2 each independently represents a number of 2 to 25.
R ³ is a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 26 carbon atoms, or a substituted or unsubstituted linear, branched or cyclic group having 1 to 26 carbon atoms. An alkenyl group is shown.   The lubricating oil composition for a traction drive transmission according to claim 1, wherein the base oil of component (A) is a naphthenic synthetic oil. The lubricating oil composition for a traction drive transmission according to claim 1 or 2, wherein the total number of carbon atoms of R ^{1 to} R ³ of the amine of the general formula (I) is 10 to 40. 4. The amine according to claim ^1, wherein R ¹ and / or R ² of the amine of the general formula (I) is a methyl group, and R ³ is an alkyl group having 8 to 22 carbon atoms having no substituent. The lubricating oil composition for traction drive transmission as described.   (B) The phosphoric acid ester compound of the component and the amine represented by the general formula (I) of the component (D) and / or an amine oxide composed of the amine are blended at a mass ratio of 35: 1 to 2: 1. The lubricating oil composition for a traction drive transmission according to any one of claims 1 to 4.   (A) Component base oil is 80 to 99% by mass, Component (B) is a phosphate ester compound of 0.05 to 10% by mass, and Component (C) is 0.1 to 1.6% by mass of antioxidant. %, The amine represented by the general formula (I) of the component (D) and / or the amine oxide composed of the amine is blended in an amount of 0.05 to 4% by mass. Lubricating oil composition for transmission.