JP6690108B2 - Lubricating oil composition for internal combustion engine of hybrid vehicle - Google Patents

Description

  The present invention relates to a lubricating oil composition for internal combustion engines used in hybrid vehicles.

In recent years, environmental regulations on a global scale have become more and more strict, and in particular, the circumstances surrounding automobiles are becoming stricter such as fuel consumption regulations and exhaust gas regulations. Behind this is environmental protection such as global warming and resource protection from concerns over oil resource depletion. From such a recent situation, the production ratio of hybrid vehicles is improving in order to reduce air pollution caused by exhaust gas from the vehicles.
By the way, as the lubricating oil for the internal combustion engine of the hybrid vehicle, the same engine oil as the lubricating oil for the internal combustion engine of the vehicle that is driven only by the conventional internal combustion engine is used. Lubricating oil is being developed.
For example, Patent Document 1 discloses that a specific lubricating base oil contains a metal-based detergent, a boron-containing succinimide-based ashless dispersant, and a metal salt of a phosphorus-containing acid in specific contents. Disclosed is a characteristic lubricating oil composition for an internal combustion engine.
Further, in Patent Document 2, a lubricating base oil has a specific content, respectively, in a specific content, a salicylate-based detergent, a succinimide-based ashless dispersant containing only boron-free succinimide-based ashless dispersant, and phosphorus-containing. A lubricating oil composition for an internal combustion engine of a hybrid vehicle, which contains a metal salt of an organic acid, and the lubricating oil composition for an internal combustion engine, and further, a boron-containing succinimide-based ashless content in a specific content Disclosed is a lubricating oil composition for an internal combustion engine of a hybrid vehicle, which comprises a powder.

JP, 2008-144018, A JP, 2008-144019, A

  By the way, a hybrid vehicle has two power sources, an internal combustion engine (for example, an engine) and an electric motor (for example, an electric motor). Then, depending on the traveling conditions, the vehicle is traveling using only the internal combustion engine, only the electric motor, or these at the same time. In the conventional vehicle having only the internal combustion engine, it is necessary to always use the power of the internal combustion engine at the time of driving, but in the hybrid vehicle, it is possible to drive the electric power obtained by the electric motor without using the power of the internal combustion engine. As described above, the internal combustion engine of the hybrid vehicle has a longer stop time than the internal combustion engine of the conventional vehicle even when the vehicle is in use. Therefore, dew condensation occurs in the crank chamber, and water is easily mixed in the internal combustion engine lubricating oil. As a result, when a lubricating oil for an internal combustion engine is used in a hybrid vehicle, the lubricating oil deteriorates earlier when used in an internal combustion engine of a hybrid vehicle than when used in a vehicle having only a conventional internal combustion engine. I have a problem that it is easy to do.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lubricating oil suitable for an internal combustion engine of a hybrid vehicle, which is excellent in high-temperature cleanability and excellent in long drainability even when water is mixed. It is to provide a composition.

As a result of intensive studies, the inventors have found that a lubricating oil composition for an internal combustion engine contains a specific hindered amine compound, an amine-based antioxidant, a metal-based detergent, and an organic zinc dithiophosphate, and the hindered amine It has been found that the above problem can be solved by containing a compound and the amine antioxidant in a specific ratio.
That is, according to the present invention, there are provided the following lubricating oil compositions for internal combustion engines [1] to [8].
[1] Base oil,
(A1) a hindered amine compound,
(A2) an amine-based antioxidant,
(B) a metallic detergent,
(C) containing organic zinc dithiophosphate,
For an internal combustion engine of a hybrid vehicle in which the content of nitrogen atoms in the component (A1) is 5 to 75 mol% based on 100 mol% of the total of nitrogen atoms in the component (A1) and nitrogen atoms in the component (A2). Lubricating oil composition.
[2] Base oil,
(A1) a hindered amine compound,
(A2) an amine-based antioxidant,
(B) a metallic detergent,
(C) Compounded with zinc organic dithiophosphate,
A hybrid vehicle in which the content of nitrogen atoms in the component (A1) is 5 to 75 mol% based on 100 mol% of the total of nitrogen atoms in the component (A1) and nitrogen atoms in the component (A2). A method for producing a lubricating oil composition for an internal combustion engine.
[3] A lubrication method comprising using the lubricating oil composition for an internal combustion engine according to [1] above.
[4] A lubricating method comprising using the lubricating oil composition for an internal combustion engine obtained by the production method described in [2] above.
[5] An internal combustion engine using the lubricating oil composition for internal combustion engines according to [1] above.
[6] An internal combustion engine using the lubricating oil composition for an internal combustion engine obtained by the production method according to [2] above.
[7] A hybrid system having an internal combustion engine using the lubricating oil composition for an internal combustion engine according to the above [1], and an electric motor as a power source.
[8] A hybrid system having an internal combustion engine, which uses the lubricating oil composition for an internal combustion engine obtained by the production method according to [2], and an electric motor as a power source.

  ADVANTAGE OF THE INVENTION According to this invention, the lubricating oil composition suitable for the internal combustion engine of a hybrid vehicle which is excellent in high temperature cleanability and also in long drain property even when water is mixed can be provided.

Hereinafter, preferred embodiments of the present invention will be described in detail.
[Lubricant composition for internal combustion engine]
A lubricating oil composition for an internal combustion engine (hereinafter, may be simply referred to as “lubricating oil composition of the present invention”), which is an embodiment of the present invention, comprises a base oil, (A1) a hindered amine compound, and (A2) Amine-based antioxidant, (B) metal-based detergent, and (C) organic zinc dithiophosphate, and a total of 100 moles of nitrogen atoms in the component (A1) and nitrogen atoms in the component (A2). The content of nitrogen atoms in the component (A1) (hereinafter, also simply referred to as “N ratio”) is 5 to 75 mol%.
If the N ratio is less than 5 mol%, the long drain property when water is mixed in the lubricating oil composition for internal combustion engines is deteriorated, which is not preferable. On the other hand, when the N ratio exceeds 75 mol%, the high temperature detergency is poor. From the viewpoint of achieving both excellent high-temperature cleanability and long drainability when water is mixed, the lower limit of the N ratio is preferably 15 mol% or more, more preferably 25 mol% or more, and further preferably 35 mol% or more. The upper limit is preferably 70 mol% or less, more preferably 65 mol% or less.
The long-drain property refers to the ability to extend the lubricating oil replacement interval by suppressing the deterioration of the lubricating oil over a long period of time, and will be specifically described later in this specification. It is evaluated by the total value of the oxidation degree and the nitriding degree measured by the method described in the examples. Then, the present inventors have found that the results obtained by the evaluation have a high correlation with the results of a test (fleet test) in which the lubricating oil composition according to one embodiment of the present invention is run in a hybrid vehicle. Have confirmed that there is.
High-temperature cleanliness means cleaning the lubricating oil by preventing dirt and deposits such as sludge, deposits, varnish / lacquer and carbon deposits generated in the lubricating oil at high temperatures from adhering to the inside of the internal combustion engine. In the present specification, it is evaluated by a merit rating (merit score) obtained by a hot tube test described in Examples described later.

The lubricating oil composition for an internal combustion engine has a total value of the degree of oxidation and the degree of nitridation after a lapse of 144 hours in a NOx gas blowing / water addition ISOT test of preferably 0.0600 or less, more preferably 0.0500 or less, It is preferably 0.0350 or less. The total value of the oxidation degree and the nitriding degree after 168 hours is preferably 0.0900 or less, more preferably 0.0700 or less, and further preferably 0.0600 or less. The lower the total value of the oxidation degree and the nitriding degree is, the better the long drain property is even when water is mixed.
In addition, the merit rating (merit rating) in the hot tube test performed at 290 ° C. for 16 hours is preferably 7 or more, more preferably 8 or more.
The higher the value of the merit rating, the better the high temperature cleanability.
The lubricating oil composition for an internal combustion engine, under the NOx gas injection / water addition ISOT test, after a lapse of 144 hours or 168 hours, a suitable range of the total value of the oxidation degree and the nitriding degree, and at 290 ° C. for 16 hours. It is more preferable to simultaneously satisfy the preferable range of the merit rating (merit score) in the hot tube test to be performed.
The total value of the oxidation degree and the nitriding degree in the above-mentioned NOx gas blowing / water addition ISOT test, and the merit rating (merit rating) in the hot tube test performed at 290 ° C. for 16 hours are described in Examples described later. This is the value obtained by the method.

<Base oil>
The base oil used in the present invention is not particularly limited, and any one can be appropriately selected and used from mineral oils and synthetic oils conventionally used as base oils for lubricating oils.
As the mineral oil, for example, a lubricating oil fraction obtained by distilling a crude oil under atmospheric pressure to obtain a lubricating oil fraction obtained by distillation under reduced pressure is subjected to solvent degassing, solvent extraction, hydrogenolysis, solvent dewaxing, catalytic degassing. Examples include waxes and base oils produced by isomerizing waxes and hydrorefined mineral oils and waxes, among which mineral oils treated by hydrorefining are used. preferable. The mineral oil treated by hydrorefining tends to have good% C _P and viscosity index described later.
As the synthetic oil, for example, polybutene, poly-α-olefin such as α-olefin homopolymer or copolymer (for example, ethylene-α-olefin copolymer), for example, polyol ester, dibasic acid ester, phosphoric acid ester. Examples thereof include various esters such as polyphenyl ether, various ethers such as polyphenyl ether, polyglycol, alkylbenzene, alkylnaphthalene, and base oil produced by isomerizing GTL WAX (gas liquid wax). Among these synthetic oils, polyα-olefins and esters are particularly preferable, and those obtained by combining these two kinds are also suitably used as synthetic oils.

In one embodiment of the present invention, as the base oil, one type of mineral oil may be used alone, or two or more types may be used in combination. Further, one kind of synthetic oil may be used, or two or more kinds thereof may be used in combination. Further, one or more mineral oils and one or more synthetic oils may be used in combination.
The base oil is a main component in the lubricating oil composition, and is usually 50% by mass or more, preferably 60 to 97% by mass, and more preferably 65 to 95% by mass with respect to the total amount of the lubricating oil composition. % Contained.

The viscosity of the base oil is not particularly limited, but the kinematic viscosity at 100 ° C. is preferably 1.0 to ²⁰ mm ² / s, more preferably 1.5 to 15 mm ² / s, further preferably 2.0 to 13 mm. The range is ² / s. The value of the kinematic viscosity is measured by the method described in Examples below.
The viscosity index of the base oil is preferably 70 or higher, more preferably 90 or higher, even more preferably 100 or higher, still more preferably 120 or higher. The base oil having a viscosity index of 70 or more has a small change in viscosity due to changes in temperature.
When the viscosity index of the base oil is within the range, it becomes easy to improve the viscosity characteristics of the lubricating oil composition. The viscosity index is an index measured by the method described in Examples below.
The above-mentioned mineral oil has a paraffin content (% C _P ) by ring analysis of preferably 60% or more, more preferably 65% or more. By setting the paraffin content to 60% or more, the oxidation stability of the base oil becomes good. The paraffin content (% C _P ) is measured by the method described in Examples below.

<(A1) component: hindered amine compound>
The (A1) hindered amine compound used in the present invention is not particularly limited, and examples thereof include compounds having at least one or more terminal structure represented by the following general formula (1-1) in the molecule.
(In the formula, R ¹ represents a hydrogen atom (—H), a methyl group (—CH ₃ ), a hydroxyl group (—OH) or an alkoxy group (—OR ² ; R ² is an alkyl group). * Represents a single bond (others). Represents the bonding position with the structure)).

The alkyl group represented by R ² is preferably a linear or branched alkyl group having 1 to 10 carbon atoms.
As the compound having at least one partial structure represented by the following general formula (1-1) in the molecule, a compound represented by the following general formula (1-2) is preferable.
(In the formula, R ¹ represents a hydrogen atom (—H), a methyl group (—CH ₃ ), a hydroxyl group (—OH) or an alkoxy group (—OR ² ; R ² is an alkyl group). R ³ is a hydrocarbyl group. Represents.)

The hydrocarbyl group represented by R ³ may be a hydrocarbyl group having any structure such as linear, branched, or cyclic, and is preferably a hydrocarbyl group having 3 to 20 carbon atoms.
Examples of the hydrocarbyl group having 3 to 20 carbon atoms include a linear or branched alkyl group having 3 to 20 carbon atoms, a linear or branched alkenyl group having 3 to 20 carbon atoms, and a carbon number. A cycloalkyl group having 5 to 13 or a linear or branched alkylcycloalkyl group, an aryl group having 6 to 18 carbon atoms or a linear or branched alkylaryl group, and an aryl having 7 to 19 carbon atoms An alkyl group is mentioned.
The hydrocarbyl group is preferably a linear or branched alkyl group or alkenyl group having 3 to 20 carbon atoms, and more preferably a linear or branched alkyl group having 5 to 15 carbon atoms.
Examples of the preferred alkyl group having 3 to 20 carbon atoms include propyl group, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1,1-dimethylethyl group, pentyl group, 1-methylbutyl group. Group, 2-methylbutyl group, 3-methylbutyl group, 1,1-dimethylpropyl group, 1,2-dimethylpropyl group, 2,2-dimethylpropyl group, 1-ethylpropyl group, hexyl group, 1-methylpentyl group , 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group , 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-ethyl-1-methylpropyl group, -Ethyl-2-methylpropyl group, heptyl group, octyl group, 2-ethylhexyl group, 6-methylheptyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group Examples thereof include linear or branched alkyl groups such as heptadecyl group, octadecyl group, nonadecyl group and eicosyl group.
Further, a preferable alkenyl group having 3 to 20 carbon atoms is, for example, an organic group obtained by extracting at least one hydrogen from each organic group exemplified by the alkyl group having 3 to 20 carbon atoms, Examples thereof include groups having one or more heavy bonds.

Specifically, for example, fatty acid (C12-21, C18 unsaturated) 2,2,6,6-tetramethyl-4-piperidinyl ester, 2,2,6,6-tetramethyl-4 -Piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 2,2,6,6-tetramethyl-4-piperidyl benzoate, bis (2,2,6,6-tetra Methyl-4-piperidyl) sebacate, bis (N-methyl-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1-octoxy-2,2,6,6-tetramethyl-4- Piperidyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyi) -4-piperidyl) -1,2,3,4-butanetetracarboxylate, bis (2,2,6,6-tetramethyl-4-piperidyl) di (tridecyl) -1,2,3,4- Butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) di (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,2) 6,6-Pentamethyl-4-piperidyl) -2-butyl-2- (3,5-di-tert-butyl-4-hydroxybenzyl) malonate, 1- (2-hydroxyethyl) -2,2,6,6 -Tetramethyl-4-piperidinol / diethyl succinate polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / 2,4-dichloro-6-morpholino-s − Bird Gin polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / 2,4-dichloro-6-tert-octylamino-s-triazine polycondensate, 1 , 5,8,12-Tetrakis [2,4-bis (N-butyl-N- (2,2,6,6-tetramethyl-4-piperidyl) amino) -s-triazin-6-yl] -1 , 5,8,12-Tetraazadodecane, 1,5,8,12-tetrakis [2,4-bis (N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl)) Amino) -s-triazin-6-yl] -1,5,8,12-tetraazadodecane, 1,6,11-tris [2,4-bis (N-butyl-N- (2,2,6) , 6-Tetramethyl-4-piperidyl) amino) -s-triazin-6-yl] a Minoundecane, 1,6,11-tris [2,4-bis (N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino) -s-triazin-6-yl ] Hindered amine compounds such as aminoundecane and the like can be mentioned. These may be used alone or in combination of two or more.
The content (nitrogen atom conversion) of the (A1) hindered amine amine compound used in the present invention is preferably 15 mass ppm or more, more preferably 25 mass ppm or more, still more preferably, based on the total amount of the lubricating oil composition for an internal combustion engine. Is 30 mass ppm or more, preferably 500 mass ppm or less, more preferably 350 mass ppm or less, still more preferably 250 mass ppm or less.

<(A2) component: amine-based antioxidant>
The (A2) amine-based antioxidant used in the present invention is not particularly limited as long as it is an antioxidant different from the hindered amine compound which is the above-mentioned (A1) component, and conventionally known ones can be used. . In the present invention, the “amine-based antioxidant” refers to an antioxidant composed of an amine compound other than the component (A1) described above.
Examples of the (A2) amine-based antioxidant include diphenylamine-based antioxidants, specifically, diphenylamine, monooctyldiphenylamine, monononyldiphenylamine, dibutyldiphenylamine, dihexyldiphenylamine, dioctyldiphenylamine, dinonyldiphenylamine, Hydrocarbyl-substituted diphenylamines such as tetrabutyldiphenylamine, tetrahexyldiphenylamine, tetraoctyldiphenylamine, tetranonyldiphenylamine, N, N-diphenyl-p-phenylenediamine; N, N'-diisopropyl-p-phenylenediamine, N, N'- Phenylenediamine such as diphenyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine and the like; and And naphthylamine type, specifically, hydrocarbyl such as α-naphthylamine, phenyl-α-naphthylamine, butylphenyl-α-naphthylamine, hexylphenyl-α-naphthylamine, octylphenyl-α-naphthylamine and nonylphenyl-α-naphthylamine. Substituted phenyl-α-naphthylamine and the like can be mentioned.
Among these, diphenylamine-based amine-based antioxidants are preferable from the viewpoint of obtaining excellent long drain property and high-temperature detergency. The diphenylamine-based amine antioxidant is preferably hydrocarbyl-substituted diphenylamine, more preferably dialkyl-substituted diphenylamine, from the viewpoint of obtaining excellent long drain property and high-temperature detergency. These may be used alone or in combination of two or more.

(Hydrocarbyl-substituted diphenylamine)
As the hydrocarbyl-substituted diphenylamine, a hydrocarbyl-substituted diphenylamine represented by the following general formula (2) is preferable.

(In the formula, R ⁴ represents a hydrocarbyl group. R ⁵ represents a hydrogen atom or a hydrocarbyl group.)

The hydrocarbyl group for R ⁴ and R ⁵ may be a hydrocarbyl group having any structure such as linear, branched or cyclic, and each independently is preferably a hydrocarbyl group having 3 to 20 carbon atoms. .
Examples of the hydrocarbyl group having 3 to 20 carbon atoms include a linear or branched alkyl group having 3 to 20 carbon atoms, a linear or branched alkenyl group having 3 to 20 carbon atoms, and a carbon number. A cycloalkyl group having 5 to 13 or a linear or branched alkylcycloalkyl group, an aryl group having 6 to 18 carbon atoms or a linear or branched alkylaryl group, and an aryl having 7 to 19 carbon atoms An alkyl group is mentioned.
The hydrocarbyl group is preferably a linear or branched alkyl group having 3 to 20 carbon atoms, more preferably a linear or branched alkyl group having 5 to 15 carbon atoms.
Examples of the preferred alkyl group having 3 to 20 carbon atoms include propyl group, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1,1-dimethylethyl group, pentyl group, 1-methylbutyl group. Group, 2-methylbutyl group, 3-methylbutyl group, 1,1-dimethylpropyl group, 1,2-dimethylpropyl group, 2,2-dimethylpropyl group, 1-ethylpropyl group, hexyl group, 1-methylpentyl group , 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group , 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-ethyl-1-methylpropyl group, -Ethyl-2-methylpropyl group, heptyl group, octyl group, 2-ethylhexyl group, 6-methylheptyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group Examples thereof include linear or branched alkyl groups such as heptadecyl group, octadecyl group, nonadecyl group and eicosyl group.
The hydrocarbyl-substituted diphenylamine represented by the general formula (2) is preferably a dialkyldiphenylamine in which R ⁴ and R ⁵ are alkyl groups, and more preferably a dialkyldiphenylamine in which R ⁴ and R ⁵ are the same alkyl group. is there.

  The content of the (A2) amine-based antioxidant used in the present invention (on a nitrogen atom basis) is, based on the total amount of the lubricating oil composition for an internal combustion engine, preferably 50 mass ppm or more, more preferably 70 mass ppm or more, The content is more preferably 90 mass ppm or more, preferably 1,000 mass ppm or less, more preferably 500 mass ppm or less, still more preferably 300 mass ppm or less.

<(B) component: metallic detergent>
Examples of the (B) metal-based detergent used in the present invention include alkali metal-based detergents and alkaline earth metal-based detergents. If the lubricating oil composition for an internal combustion engine does not contain the (B) metal-based detergent, the high-temperature detergency and / or the long drain property when water is mixed are inferior.
Specific examples include one or more metal-based detergents selected from alkali metal sulfonates or alkaline earth metal sulfonates, alkali metal phenates or alkaline earth metal phenates, alkali metal salicylates, alkaline earth metal salicylates, and the like. To be In addition, the alkali metal includes sodium and potassium, and the alkaline earth metal includes magnesium, calcium, and barium, preferably one or more selected from sodium, magnesium, and calcium, and more preferably calcium.

The alkali metal sulfonate or alkaline earth metal sulfonate is preferably an alkylaromatic sulfonic acid obtained by sulfonation of an alkylaromatic compound having a weight average molecular weight of 300 to 1,500, more preferably 400 to 700. Examples thereof include alkali metal salts and alkaline earth metal salts.
Examples of the alkali metal phenate or alkaline earth metal phenate include an alkali metal salt or an earth metal salt of a Mannich reaction product of an alkylphenol, an alkylphenol sulfide, or an alkylphenol.
Examples of the alkali metal salicylate or alkaline earth metal salicylate include alkali metal salts or alkaline earth metal salts of alkylsalicylic acid.
The alkyl group constituting the alkali metal-based detergent or alkaline earth metal-based detergent preferably has 4 to 30 carbon atoms, and more preferably is a 6 to 18 linear or branched alkyl group. , These may be linear or branched.
These may also be primary alkyl groups, secondary alkyl groups or tertiary alkyl groups.

Further, as the metal-based detergent, a neutral alkali metal sulfonate or a neutral alkaline earth metal sulfonate, a neutral alkali metal phenate or a neutral alkaline earth metal phenate, a neutral alkali metal salicylate or a neutral alkaline earth metal. (B1) Neutral metal detergent (base number: 10 to 80 mgKOH / g) such as neutral alkali metal detergent or neutral alkaline earth metal detergent such as salicylate; and (B2) overbased alkali Overbased alkali metal such as metal sulfonate or overbased alkaline earth metal sulfonate, overbased alkali metal phenate or overbased alkaline earth metal phenate, overbased alkali metal salicylate or overbased alkaline earth metal salicylate Detergents or overbased metal detergents such as overbased alkaline earth metal detergents (Base number: 150~500mgKOH / g); contains.
The base number of the metallic detergent used in the present invention means the base number measured by the perchloric acid method according to JIS K2501.

In addition, as the method for obtaining the neutral alkaline earth metal sulfonate, the neutral alkaline earth metal phenate, and the neutral alkaline earth metal salicylate as the component (B1), for example, the above-mentioned alkylaromatic sulfonic acid, alkylphenol, and alkylphenol can be used. Mannich reaction products of sulfides and alkylphenols, alkylsalicylic acids, etc. are directly reacted with alkaline earth metal bases such as alkaline earth metal oxides and hydroxides of magnesium and / or calcium, or once sodium salts or potassium salts And the like, and the like, and the like, which is obtained by substituting the alkaline earth metal salt with an alkali metal salt such as
Further, as a method of obtaining the overbased alkaline earth metal sulfonate, the overbased alkaline earth metal phenate and the overbased alkaline earth metal salicylate as the component (B2), for example, neutral carbon dioxide in the presence of carbon dioxide gas can be used. Examples thereof include a method of obtaining an alkaline earth metal sulfonate, a neutral alkaline earth metal phenate and a neutral alkaline earth metal salicylate by reacting an alkaline earth metal carbonate or borate.
Of these, (B1) the neutral metal-based detergent has a cleaning action which is the main function of the detergent. The overbased metal detergent (B2) is superior to the component (B1) in its ability to neutralize an acid such as an organic acid produced by oxidative deterioration in the lubricating oil or a nitric acid produced by combustion.

  These metal-based detergents may be used alone or in combination of two or more. Among the above-mentioned ones, the metal-based detergent preferably contains (B1) a neutral metal-based detergent from the viewpoint of improving high-temperature detergency, and is suitable for high-temperature detergency and long drainage when water is mixed. From the viewpoint of improving the property, more preferred is a combination of (B1) a neutral metal-based detergent and (B2) an overbased detergent. Specifically, the metal-based detergent preferably contains at least one selected from neutral alkaline earth metal sulfonates, neutral alkaline earth metal phenates, and neutral alkaline earth metal salicylates, and more preferably the metal. As the system detergent, preferably one or more selected from neutral alkaline earth metal sulfonates, neutral alkaline earth metal phenates and neutral alkaline earth metal salicylates, and overbased alkaline earth metal sulfonates and overbased alkalis. It is a combination of one or more selected from earth metal phenates and overbased alkaline earth metal salicylates. More specifically, it preferably contains at least one selected from neutral calcium sulfonate, neutral magnesium sulfonate and neutral sodium sulfonate, and more preferably overbased calcium salicylate and neutral calcium sulfonate, medium It is a combination with at least one selected from the group consisting of neutral magnesium sulfonate and neutral sodium sulfonate, and more preferably a combination of overbased calcium salicylate and neutral calcium sulfonate.

The content (B) of the metal-based detergent used in the present invention (in terms of metal atoms) is the above-mentioned lubricating oil composition for an internal combustion engine from the viewpoint of improving high-temperature detergency and / or long drainability when water is mixed. It is preferably 50 mass ppm or more, more preferably 150 mass ppm or more, still more preferably 500 mass ppm or more, still more preferably 800 mass ppm or more, still more preferably 1,000 mass ppm or more, based on the total amount of the substances. Further, from the viewpoint of reducing the risk that the content of the metal-based detergent (in terms of metal atoms) is excessive and the distribution is increased, causing piston ring wear and metal corrosion, it is preferably 3,000 mass ppm or less, The content is more preferably 2,500 mass ppm or less, further preferably 2,400 mass ppm or less.
Among them, the content of the (B1) neutral metal detergent (on a metal atom basis) is preferably 50 mass ppm or more, more preferably 80 mass ppm or more, based on the total amount of the lubricating oil composition for an internal combustion engine. It is more preferably 100 mass ppm or more, preferably 500 mass ppm or less, more preferably 300 mass ppm or less, and further preferably 200 mass ppm or less.
The content of the component (B1) with respect to the total amount of the component (B) (equivalent to metal atom) (equivalent to metal atom) is preferably 1 to 25% by mass, from the viewpoint of obtaining excellent high-temperature cleanability. It is preferably 2 to 15% by mass, and more preferably 5 to 10% by mass.

<(C) component: Zinc organic dithiophosphate>
The organic zinc dithiophosphate (C) used in the present invention is not particularly limited, and examples thereof include compounds represented by the following general formula (3). When the lubricating oil composition contains the component (C), good oxidation stability and wear resistance can be obtained.

(In the formula, R ⁶ , R ⁷ , R ⁸ and R ⁹ each independently represent a hydrocarbyl group having 1 to 24 carbon atoms.)

Examples of the hydrocarbyl group having 1 to 24 carbon atoms include a linear or branched alkyl group having 1 to 24 carbon atoms, a linear or branched alkenyl group having 3 to 24 carbon atoms, and 5 to 5 carbon atoms. 13 cycloalkyl group or linear or branched alkylcycloalkyl group, aryl group having 6 to 18 carbon atoms or linear or branched alkylaryl group, and arylalkyl group having 7 to 19 carbon atoms However, among these, an alkyl group is preferable.
The component (C) is preferably zinc dialkyldithiophosphate, more preferably secondary zinc dialkyldithiophosphate. These may be used alone or in combination of two or more.
The content of the component (C) is, based on the total amount of the lubricating oil composition for an internal combustion engine, preferably 0.005 to 0.30 mass%, more preferably 0.01 to 0.15 mass% in terms of phosphorus amount. Is. When the content is within the above range, wear resistance and oxidation stability can be imparted to the lubricating oil composition for internal combustion engines.

<(D) component: Phenolic antioxidant>
The above lubricating oil composition for an internal combustion engine preferably further contains (D) a phenolic antioxidant from the viewpoint of obtaining excellent high-temperature detergency and excellent long drain property even when water is mixed.
The component (D) is not particularly limited, but is, for example, 4,4′-methylenebis (2,6-di-tert-butylphenol), 4,4′-bis (2,6-di-tert-butylphenol). , 4,4'-bis (2-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 2,2'-methylenebis (4-methyl-6-) tert-butylphenol), 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), 4,4′-isopropylidenebis (2,6-di-tert-butylphenol), 2,2′-methylenebis ( 4-methyl-6-nonylphenol), 2,2'-isobutylidene bis (4,6-dimethylphenol); 2,2'-methylenebis (4-methyl-) 6-cyclohexylphenol), 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, 2, 6-di-tert-amyl-p-cresol, 2,6-di-tert-butyl-4- (N, N'-dimethylaminomethylphenol), 4,4'-thiobis (2-methyl-6-t -Butylphenol), 4,4'-thiobis (3-methyl-6-tert-butylphenol), 2,2'-thiobis (4-methyl-6-tert-butylphenol), bis (3-methyl-4-hydroxy-). 5-tert-butylbenzyl) sulfide, bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, n-octyl-3- ( 4-hydroxy-3,5-di-tert-butylphenyl) propionate, n-octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2,2'-thio [diethyl- Bis-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and the like.
Among these, bisphenol type and ester group-containing phenol type are particularly preferable. These may be used alone or in combination of two or more.
The content of the component (D) is, based on the total amount of the lubricating oil composition for an internal combustion engine, preferably 0.1 to 5.0% by mass, more preferably 0.2 to 3.0% by mass, and further preferably It is 0.2 to 1.5 mass%.

[Other ingredients]
The lubricating oil composition for internal combustion engines may further contain other components other than the components (A) to (D). As other components, a viscosity index improver, an antioxidant other than the above-mentioned components (A1), (A2) and (D) (hereinafter, also simply referred to as "other antioxidant"), a friction modifier, and a resistance. Examples include abrasion agents, extreme pressure agents, ashless dispersants, metal deactivators, oiliness agents, pour point depressants, rust preventives, defoamers and the like.

Examples of the viscosity index improver include polymethacrylate (PMA) type (for example, polyalkylmethacrylate, polyalkylacrylate and the like), olefin copolymer (OCP) type (for example, ethylene-propylene copolymer (EPC), polybutylene). Etc.), styrene-based copolymers (for example, polyalkylstyrene, styrene-diene hydrogenated copolymer, styrene-maleic anhydride ester copolymer, etc.) and the like. Examples of the PMA-based viscosity index improver include a dispersion type and a non-dispersion type. The dispersion type PMA viscosity index improver is a homopolymer of alkyl methacrylate or alkyl acrylate, and the non-dispersion type PMA viscosity index improver is alkyl methacrylate or alkyl acrylate and a polar monomer having dispersibility. (For example, diethylaminoethyl methacrylate and the like). Further, like the PMA type, the OCP type viscosity index improver also has a dispersion type. These viscosity index improvers usually have a weight average molecular weight of 5,000 to 1,500,000, and in the case of PMA, preferably 20,000 or more, more preferably 100,000 or more, and It is preferably 1,000,000 or less, more preferably 800,000 or less. Further, in the case of OCP type, it is preferably 10,000 or more, more preferably 20,000 or more, and preferably 800,000 or less, more preferably 500,000 or less.
These viscosity index improvers may be contained alone or in any combination of plural kinds. The blending amount is preferably 0.01% by mass or more, and preferably 8.0% by mass or less, more preferably 6.0% by mass or less, and further based on the total amount of the lubricating oil composition for an internal combustion engine. It is preferably 4.0% by mass or less.

Examples of other antioxidants include sulfur-based antioxidants and phosphorus-based antioxidants. These can be appropriately selected and used from known antioxidants conventionally used as antioxidants for lubricating oils.
Examples of the sulfur-based antioxidant include dilauryl-3,3′-thiodipropionate and the like, and examples of the phosphorus-based antioxidant include phosphite and the like.
As the molybdenum amine complex-based antioxidant, a hexavalent molybdenum compound, specifically, one obtained by reacting molybdenum trioxide and / or molybdic acid with an amine compound can be used.
These antioxidants may be contained alone or in any combination of plural kinds.
The total content of these antioxidants including the above-mentioned components (A1), (A2), (D), and other antioxidants is preferably 0.1% based on the total amount of the lubricating oil composition for an internal combustion engine. The content is 01 to 10% by mass, more preferably 0.1 to 5.0% by mass.

Specific examples of the friction modifier and the antiwear agent include sulfur compounds such as sulfurized olefins, dialkyl polysulfides, diarylalkyl polysulfides, and diaryl polysulfides, phosphoric acid esters, thiophosphoric acid esters, phosphorous acid esters, and alkylhydrogens. Phosphite, phosphorous compounds such as amine salt of phosphoric acid ester, amine salt of phosphorous acid ester, zinc dithiocarbamate (ZnDTC), sulfurized oxymolybdenum organophosphorodithioate (MoDTP), sulfurized oxymolybdenum dithiocarbamate (MoDTC), etc. Ashless friction modifiers such as organometallic compounds, amine compounds, fatty acid esters, fatty acid amides, fatty acids, aliphatic alcohols, aliphatic ethers, urea compounds, hydrazide compounds and the like can be mentioned. These friction modifiers and antiwear agents may be contained alone or in any combination of plural kinds. The content thereof is preferably 0.01 to 8.0% by mass, more preferably 0.05 to 5.0% by mass, further preferably 0.1 to 1 based on the total amount of the lubricating oil composition for an internal combustion engine. It is in the range of 0.0% by mass.
As the extreme pressure agent, for example, sulfurized compounds such as sulfurized olefins, dialkyl polysulfides, diaryl alkyl polysulfides, diaryl polysulfides, phosphoric acid esters, thiophosphoric acid esters, phosphorous acid esters, alkyl hydrogen phosphites, phosphoric acid ester amine salts, Examples thereof include phosphorus compounds such as a phosphite amine salt. These extreme pressure agents may be contained alone or in any combination of plural kinds. The content thereof is preferably 0.01 to 10% by mass based on the total amount of the lubricating oil composition for internal combustion engines.
Examples of the ashless dispersant include polybutenyl succinimide having a polybutenyl group having a number average molecular weight of 900 to 3,500, polybutenylbenzylamine, polybutenylamine, and derivatives thereof such as boric acid modified products. Etc. These ashless dispersants may be contained alone or in any combination of plural kinds.

Examples of the metal deactivator include benzotriazole, triazole derivatives, benzotriazole derivatives, thiadiazole derivatives and the like. These metal deactivators may be contained alone or in any combination of plural kinds. The content thereof is preferably 0.01 to 3.0% by mass, more preferably 0.02 to 1.0% by mass, based on the total amount of the lubricating oil composition for an internal combustion engine.
Examples of the oiliness agent include aliphatic saturated and unsaturated monocarboxylic acids such as stearic acid and oleic acid, polymerized fatty acids such as dimer acid and hydrogenated dimer acid, ricinoleic acid, hydroxy fatty acids such as 12-hydroxystearic acid, and lauryl. Alcohols, aliphatic saturated and unsaturated monoalcohols such as oleyl alcohol, stearylamine, aliphatic saturated and unsaturated monoamines such as oleylamine, lauric acid amides, aliphatic saturated and unsaturated monocarboxylic acid amides such as oleic acid amide Can be mentioned. These oiliness agents may be contained alone or in any combination of plural kinds. The content thereof is preferably 0.01 to 5.0% by mass, more preferably 0.02 to 1.0% by mass, based on the total amount of the lubricating oil composition for an internal combustion engine.
As the pour point depressant, for example, ethylene-vinyl acetate copolymer, condensate of chlorinated paraffin and naphthalene, condensate of chlorinated paraffin and phenol, polymethacrylate type (polyalkylmethacrylate, polyalkylacrylate, etc.) , Polyalkyl styrene, polyvinyl acetate, polybutene, etc., and polymethacrylates are preferably used. These pour point depressants can be contained alone or in any combination of plural kinds. The content thereof is preferably 0.01 to 5.0% by mass, more preferably 0.01 to 1.0% by mass, based on the total amount of the lubricating oil composition for an internal combustion engine.
Examples of the rust preventive agent include dodecenyl succinic acid half ester, octadecenyl succinic anhydride, alkyl or alkenyl succinic acid derivatives such as dodecenyl succinic acid amide, sorbitan monooleate, glycerin monooleate, pentaerythritol monooleate, etc. The polyhydric alcohol partial ester, rosin amine, amines such as N-oleyl sarcosine, dialkyl phosphite amine salt and the like can be used. These rust preventives may be contained alone or in any combination of plural kinds. The content thereof is preferably 0.01 to 5.0% by mass, more preferably 0.05 to 2.0% by mass, based on the total amount of the lubricating oil composition for an internal combustion engine.
Examples of the defoaming agent include dimethyl polysiloxane and polyacrylate. These antifoaming agents may be contained alone or in any combination of plural kinds. The content thereof is preferably 0.0002 to 0.15% by mass, and more preferably 0.0005 to 0.10% by mass, based on the total amount of the lubricating oil composition for an internal combustion engine.

[Method for producing lubricating oil composition for internal combustion engine]
A method for producing a lubricating oil composition for an internal combustion engine, which is an embodiment of the present invention, comprises a base oil, (A1) a hindered amine compound, (A2) an amine antioxidant, and (B) a metal detergent. (C) Zinc organic dithiophosphate is blended, and the content of nitrogen atoms in the component (A1) is 100 mol% of the total of the nitrogen atoms in the component (A1) and the nitrogen atoms in the component (A2). Is 5 to 75 mol%, which is a method for producing a lubricating oil composition for an internal combustion engine of a hybrid vehicle. In addition, in the manufacturing method, it is preferable to add the component (D) in addition to these components, and other components may be added.
The base oil, the components (A1) to (D), and the other components are the same as above, and the lubricating oil composition for an internal combustion engine obtained by the production method is as described above. Is omitted.
In the manufacturing method, the components (A1) to (D) and the other components may be blended with the base oil by any method, and the method is not limited.

  As a lubricating method using the internal combustion engine lubricating oil composition according to one embodiment of the present invention, the internal combustion engine lubricating oil composition according to one embodiment of the present invention is filled in an internal combustion engine such as an engine. , A method of lubricating each component of the internal combustion engine. The above-described lubricating oil composition for an internal combustion engine according to one embodiment of the present invention is more preferably used as a lubricating oil that lubricates between parts of an internal combustion engine included in a hybrid system described below.

[Hybrid system using lubricating oil composition for internal combustion engine]
Another embodiment of the present invention is a hybrid system having, as a power source, an internal combustion engine and an electric motor using the above lubricating oil composition for an internal combustion engine. For example, it is preferably a hybrid system having an engine and an electric motor using the above lubricating oil composition for an internal combustion engine as engine oil. Examples of devices having the hybrid system include hybrid cars, hybrid motorcycles, hybrid trains, and hybrid ships.
The lubricating oil composition for an internal combustion engine, which is one embodiment of the present invention, is preferably used to fill the internal combustion engines of these hybrid systems and lubricate each component of the internal combustion engine.

  The present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

In the present specification, the physical properties of the raw materials used in Examples and Comparative Examples are measured according to the following procedures.
(1) Kinematic viscosity It is a value measured using a glass capillary viscometer according to JIS K2283.
(2) Viscosity index It is a value measured according to JIS K2283.
(3) NOACK evaporation amount It is a value measured according to the method specified in JPI-5S-41.
(4) Paraffin content by ring analysis (% _CP )
The ratio (percentage) of the paraffin component calculated by the ring analysis n-d-M method is shown and measured according to ASTM D-3238.
(5) Base number It is measured by the perchloric acid method according to JIS K2501.
(6) Weight average molecular weight (Mw) of poly (meth) acrylate
The weight average molecular weight (Mw) is a value obtained by measuring under the following conditions and using polystyrene as a calibration curve, and in detail, it is measured under the following conditions.
Equipment: Agilent 1260 type HPLC column: Shodex LF404 x 2 solvent: Chloroform Temperature: 35 ° C
Sample concentration: 0.05% Calibration curve: Polystyrene
Detector Nitrogen content in differential refraction detector (7) (A1) and (A2) component It is the value measured by the chemiluminescence method based on JIS K2609.
(8) Content of elements other than the above-mentioned nitrogen content-Contents of calcium, phosphorus, zinc, and boron are values measured according to JPI-5S-38-92.
The sulfur content is a value measured according to JIS K2542.

The evaluation method of the lubricating oil composition of each Example and Comparative Example is as follows.
[Long drain property]
Using the lubricating oil compositions of Examples and Comparative Examples, a NOx gas blowing / water addition ISOT test was conducted under the following conditions. The lubricating oil compositions before the test start, 144 hours, and 168 hours later were red. External spectroscopy (IR) measurement was performed, the oxidation degree and the nitriding degree were determined from the obtained infrared absorption spectrum, and the total value thereof was calculated.
(Oxidation degree)
In the infrared absorption spectrum obtained before the start of the deterioration test, the transmittance of the wave number having the highest transmittance (% T) was I ₀ , and the transmittance of the wave number of 1710 cm ⁻¹ was I.
In the IR absorption spectrum obtained after the deterioration test (after 144 hours or 168 hours), the transmittance of the wave number with the highest transmittance was I ₀ ′, and the transmittance of the wave number 1710 cm ⁻¹ was I ′.
The degree of oxidation was calculated using the following formula. The wave number of 1710 cm ^-1 is an absorption wavelength derived from (C = O) of the deteriorated acid [-O- (C = O)-], and the larger the value of the oxidation degree, the more the oxidation deterioration of the lubricating oil composition. Indicates that you are making progress.
Degree of oxidation = log ₁₀ (I ₀ '/ I')-log ₁₀ (I ₀ / I)

(Nitriding degree)
In the infrared absorption spectrum obtained after the deterioration test (after 144 hours or 168 hours), when an absorption peak was detected at a wave number of 1630 cm ⁻¹ , the transmittance indicated by the peak apex i was defined as I. Next, a straight line connecting local maxima on both sides of the peak apex was drawn and used as a baseline. Then, the intersection of the straight line drawn from the peak apex in the baseline direction in parallel with the Y axis (transmittance) and the baseline is set to i ₀ (point of wavenumber 1630 cm ^{−1 in} the baseline), and the intersection The transmittance indicated by i ₀ was defined as I ₀ .
The nitriding degree was calculated using the following formula. The wave number of 1630 cm ⁻¹ is the absorption wavelength of nitroester, and the higher the nitriding degree, the more the deterioration of the lubricating oil composition due to NOx.
Nitriding degree = log ₁₀ (I ₀ / I)

<Test conditions>
Testing machine: ISOT TESTER manufactured by Yoshida Scientific Instruments Co., Ltd.
Volume of test container: 500mL
Amount of lubricating oil composition used: 300 mL
NOx gas amount: 2,000 volume ppm with respect to the total amount of supply gas
Amount of pure water added: 5% by volume with respect to the total amount of the lubricating oil composition every 24 hours Stirring speed: 800 r / min
Test temperature (cycle): (1) 60 ° C, 4 hours, (2) 95 ° C, 2 hours, (3) 120 ° C, 12 hours, (4) 60 ° C, 6 hours; (1) to (4) The temperature conditions of (4) were changed in this order, after the condition of (4) was returned to the conditions of (1) again, and the temperature was changed again in the order of (1) to (4).
[High temperature cleanliness]
A hot tube test was conducted using the lubricating oil compositions of the examples and comparative examples. The hot tube test was set at a test temperature of 290 ° C., and other conditions were performed according to JPI-5S-55-99. In accordance with JPI-5S-55-99, the glass tube after the test was evaluated in 0.5 steps at 0 points (black) to 10 points (colorless) (merit point), and evaluated in 21 steps. The higher the number, the better the high temperature cleanability.

[Examples 1 to 8 and Comparative Examples 1 to 4]
As shown in Tables 1 and 2 below, the base oil was blended with the components shown in Tables 1 and 2 below, and the lubricating oil composition of each of Examples and Comparative Examples containing the base oil and each of these components was blended. The thing was prepared. Further, the lubricating oil compositions of Examples and Comparative Examples were evaluated according to the above evaluation method. The obtained results are shown in Tables 1 and 2 below.

In addition, each component in the following Table 1 and Table 2 represents the following.
Base oil: Group III 100N hydrorefined base oil, 100 ° C. kinematic viscosity 4.1 mm ² / s, viscosity index 134, NOACK evaporation (250 ° C., 1 hour) 12.9 mass%, ndM ring analysis % _C P 87.7%
Component (A1): hindered amine compound (trade name “XPDL-590”, manufactured by BASF Corporation, main component: 2,2,6,6-tetramethylpiperidin-4-yl dodecanoate, nitrogen (N) content 4. 13% by mass)
Component (A2): hydrocarbyl-substituted diphenylamine (trade name "Sumilyzer 9A", manufactured by Sumitomo Chemical Co., Ltd., main component: dinonyldiphenylamine, nitrogen (N) content 3.06% by mass)
・ (B) component: Metal-based detergent;
(B1) Neutral metal detergent (active ingredient 57% by mass, base oil content 43% by mass): neutral calcium sulfonate, base number (perchloric acid method) 17 mgKOH / g, calcium content 2.15% by mass, sulfur Content 3.44% by mass
(B2) Overbased metal detergent (active ingredient 65% by mass, base oil content 35% by mass): overbased calcium salicylate, base number (perchloric acid method) 225 mg KOH / g, calcium content 7.80% by mass
Component (C): zinc dialkyldithiophosphate (ZnDTP) -containing engine oil package (containing at least ZnDTP, butenyl succinimide, boron-containing polybutenyl succinimide. Element content is phosphorus content based on the package total amount) 1.07% by mass, zinc content 1.17% by mass, sulfur content 2.42% by mass, nitrogen content 0.79% by mass, boron content 0.37% by mass)
Component (D): phenolic antioxidant (octadecyl-3- (3,5-di-tert-butyl 4-hydroxyphenyl) propionate)
Other components Viscosity index improver: polyalkyl (meth) acrylate, a mixture of a weight average molecular weight of 420,000 and a weight average molecular weight of 230,000 As other additives in Tables 1 and 2 below, friction modifiers: Mo-DTC, Oiliness agent: oleic acid diethanolamide, copper deactivator: benzotriazole, antifoaming agent: dimethylpolysiloxane, pour point depressant: polymethacrylate (PMA). In addition, in the other additives described in Tables 1 and 2 below, the compounding ratios of these additives were the same in any of Examples 1 to 8 and Comparative Examples 1 to 4.

As is clear from the results of Table 1, the lubricating oil compositions of the respective examples suppress the increase in the total value of the oxidation degree and the nitriding degree after 144 hours and 168 hours in the NOx gas injection / water addition ISOT test. Therefore, it was confirmed that it has an excellent long drain property even when water is mixed. Further, as is clear from the result of the hot tube test, it was confirmed that the sample also had excellent high temperature cleanability.
On the other hand, as is clear from the results of Table 2, the content of nitrogen atoms in the component (A1) is 100 mol% in total of the nitrogen atoms in the component (A1) and the nitrogen atoms in the component (A2). On the other hand, in Comparative Example 1 in which the content was 0 mol%, it was confirmed that the long drain property was inferior to the respective Examples. In addition, in Comparative Examples 2 to 4 in which the content of nitrogen atoms in the component (A1) was 80 to 100 mol%, it was confirmed that the high temperature cleanability was remarkably inferior to the respective Examples.

  INDUSTRIAL APPLICABILITY The lubricating oil composition for an internal combustion engine of a hybrid vehicle of the present invention is excellent in high-temperature detergency and has a long drain property even when water is mixed therein, and thus can be suitably used for an internal combustion engine of a hybrid vehicle.

Claims (8)

Base oil,
(A1) a hindered amine compound represented by the following general formula (1-2),

(In the formula, R ¹ represents a hydrogen atom (—H), a methyl group (—CH ₃ ), a hydroxyl group (—OH) or an alkoxy group (—OR ² ; R ² is an alkyl group). R ³ is a straight chain. Represents a hydrocarbyl group.
(A2) an amine-based antioxidant,
(B) a metallic detergent,
(C) containing organic zinc dithiophosphate,
For an internal combustion engine of a hybrid vehicle, wherein the content of nitrogen atoms in the component (A1) is 10 to 70 mol% based on 100 mol% of the total of nitrogen atoms in the component (A1) and nitrogen atoms in the component (A2). Lubricating oil composition.   The lubricating oil composition for an internal combustion engine of a hybrid vehicle according to claim 1, wherein the amine antioxidant (A2) is a hydrocarbyl-substituted diphenylamine.   (B) The metal-based detergent is an overbased calcium salicylate and one or more kinds selected from neutral calcium sulfonate, neutral magnesium sulfonate and neutral sodium sulfonate, of the hybrid vehicle according to claim 1 or 2. A lubricating oil composition for an internal combustion engine.   The lubricating oil composition for internal combustion engines of hybrid vehicles according to any one of claims 1 to 3, further comprising (D) a phenolic antioxidant.   The lubricating oil composition, based on the total amount thereof, containing 50 to 500 mass ppm (metal atom conversion) of one or more selected from the above-mentioned neutral calcium sulfonate, neutral magnesium sulfonate and neutral sodium sulfonate. A lubricating oil composition for an internal combustion engine of a hybrid vehicle. Base oil,
(A1) a hindered amine compound represented by the following general formula (1-2),

(In the formula, R ¹ represents a hydrogen atom (—H), a methyl group (—CH ₃ ), a hydroxyl group (—OH) or an alkoxy group (—OR ² ; R ² is an alkyl group). R ³ is a straight chain. Represents a hydrocarbyl group.
(A2) an amine-based antioxidant,
(B) a metallic detergent,
(C) Compounded with zinc organic dithiophosphate,
A hybrid vehicle in which the content of nitrogen atoms in the component (A1) is 10 to 70 mol% based on 100 mol% in total of the nitrogen atoms in the component (A1) and the nitrogen atoms in the component (A2). A method for producing a lubricating oil composition for an internal combustion engine.   A lubricating method comprising using the lubricating oil composition for an internal combustion engine according to any one of claims 1 to 5.   A hybrid system comprising an internal combustion engine using the lubricating oil composition for an internal combustion engine according to claim 1 and an electric motor as a power source.