JPH10130680A - Lubricating oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a compsn. which retains good lubricating properties even after being aged and is useful as a low-fuel-consumption engine oil by compounding a lube base oil with a molybdenum compd., a thiocarbamoyl compd., and a metal-cleaning agent and/or an ashiless dispersant. SOLUTION: A lube base oil is compounded with at least one molybdenum compd. selected from among molybdenum oxysulfide dithiocarbamate represented by formula I (wherein R<1> to R<4> are each a hydrocarbon group; and X<1> to X<4> are each an oxygen or sulfur atom), a molybdenum oxysulfde dithiocarbamate represented by formula II (wherein R<5> to R<8> are each a hydrocarbon group: and X<5> to X<8> are each an oxygen or sulfur atom), and an a molybdenum amine compd. obtd. by reacting a hexavalent molybdenum compd. with amino compd. represented by the formula: R<9> NHR<10> (wherein R<9> and R<10> re each H or a hydrocarbon group), a thiocarbamoyl compd. represented by formula III [wherein R<11> to R<14> are each a 6C or higher hydrocarbon group; and Y is (S)n n (wherein (n) is 1-7], and a metal-cleaning agent and/or an ashless dispersant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a lubricating oil composition containing a molybdenum compound, a thiocarbamoyl compound, and a metal detergent and / or an ashless dispersant.

[0002]

2. Description of the Related Art At present, the situation surrounding automobiles is becoming stricter, such as fuel efficiency regulations and exhaust gas regulations. Behind this is environmental protection such as global warming, air pollution and acid rain, and resource protection from concerns about depletion of petroleum energy. At present, improvement of fuel efficiency is the most effective countermeasure.

In order to improve the fuel efficiency of automobiles, the automobile itself has been improved by reducing the weight of the automobile, improving the engine, etc., as well as reducing the viscosity of engine oil to prevent friction loss in the engine.
Improvement of engine oil, such as addition of a good friction modifier, is also an important factor.

[0004] The engine oil acts as a lubricant between the piston and the liner. In this portion, since there is much fluid lubrication, friction loss can be reduced by lowering the viscosity of the engine oil. For this reason, in recent years, the viscosity of oil has been reduced, but problems such as deterioration of sealability and increase in wear due to the reduction in viscosity have occurred. Further, engine oil also plays an important role in valve trains and bearings. However, in this area, mixed lubrication and boundary lubrication are common, so lowering the viscosity of oil causes increased wear. Therefore, a friction modifier, an extreme pressure agent, and the like are added for the purpose of reducing friction loss due to lowering the viscosity of oil and preventing wear.

[0005] Organic molybdenum compounds are used in various lubricating oils because they have an excellent friction reducing effect. However, they are particularly effective for fuel saving in engine oils and are essential for fuel saving oils. Additive. A fuel-saving oil is a new oil that, even if it has excellent fuel-saving performance, cannot be said to be excellent as a fuel-saving oil if its performance cannot be maintained. Maintaining it is an important theme at present.

[0006] Since the friction reducing performance of the organic molybdenum compound is deteriorated due to the deterioration, in recent years, the formulation of the oil to which the organic molybdenum compound is added to maintain the friction reducing performance has been studied. Among them, a thiocarbamoyl compound (dithiocarbamate compound) is a powerful additive for use with an organic molybdenum compound.

For example, in Japanese Patent Application Laid-Open No. 6-184578,
Proposed is an engine oil composition comprising a base oil blended with a metal detergent, zinc dialkyldithiophosphate and an ashless dispersant containing boron, and at least one additive component of an aliphatic amide compound and a dithiocarbamate compound dissolved therein. Have been.

[0008] Japanese Patent Publication No. 31760/1991 proposes a fatigue life improving lubricant composition obtained by combining an alkylthiocarbamoyl compound and molybdenum dithiocarbamate or molybdenum dithiophosphate.

Furthermore, Japanese Patent Publication No. 4-32877 proposes a fatigue life improving lubricant composition comprising a dithiocarbamic acid ester and / or an alkylthiocarbamoyl compound and a 1,3,4-thiadiazole compound.

[0010]

However, Japanese Patent Application Laid-Open No.
With the composition described in -184578, the performance with new oil was excellent, but the performance at the time of deterioration was still insufficient.

In addition, Japanese Patent Publication No. 3-31760 and Japanese Patent Publication No. 4
No. 32877 has a problem in solubility because the alkylthiocarbamoyl compound used has a short carbon chain.

By the way, metal detergents are common components as lubricating oil additives, and they are also known to have a friction reducing effect (for example, Japanese Patent Publication No. 6-62983).
issue). Ashless dispersants are also common components as lubricating oil additives.

Accordingly, it is an object of the present invention to provide a lubricating oil composition which maintains good lubricity even after deterioration and is particularly useful as a fuel-saving engine oil.

[0014]

Means for Solving the Problems The present inventors have conducted intensive studies and have found that a stable lubrication can be obtained by blending a molybdenum compound, a thiocarbamoyl compound having 6 or more carbon atoms, a metal detergent and / or an ashless dispersant. A lubricating oil composition that provides lubricity has been invented.

That is, according to the present invention, the lubricating base oil is represented by the general formula (1)

Embedded image (Wherein, R ^{1 to} R ⁴ represent a hydrocarbon group, and X ^{1 to} X
⁴ represents oxymolybdenum dithiocarbamate represented by an oxygen atom or a sulfur atom (hereinafter referred to as "Mo
DTC ”), general formula (2)

Embedded image (Wherein, R ^{5 to} R ⁸ represent a hydrocarbon group, and X ^{5 to} X
⁸ represents an oxygen atom or a sulfur atom; sulfurized oxymolybdenum dithiophosphate (hereinafter referred to as "Mo
DTP ") and a hexavalent molybdenum compound represented by the following general formula (3)

[Image Omitted] R ⁹ -NH-R ¹⁰ (3) (wherein R ⁹ and R ¹⁰ represent a hydrogen atom and / or a hydrocarbon group, but not at the same time a hydrogen atom) One or more molybdenum compounds selected from the group consisting of molybdenum amine compounds (hereinafter referred to as “MoAm”) obtained by reacting with an amino compound;
As the component (B), general formula (4)

Embedded image Wherein R ^{11 to} R ¹⁴ represent a hydrocarbon group having 6 or more carbon atoms, Y represents — (S) _n —, and n represents a number of 1 to 7; And (C)
A lubricating oil composition comprising, as a component, a metal detergent and / or an ashless dispersant.

The lubricating oil composition of the present invention may further comprise, if necessary, a component represented by the following general formula (5):

Embedded image (Where a represents a number of 0 to 1/3, and R ¹⁵ and R
¹⁶ represents a hydrocarbon group), zinc dithiophosphate (hereinafter, referred to as “ZDTP”), and / or
Or the following general formula (6)

Embedded image (Wherein, R ^{17 to} R ²⁰ represent a hydrocarbon group) (hereinafter, referred to as “ZDTC”).

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The molybdenum compound as the component (A) of the present invention comprises MoDTC represented by the general formula (1):
One of MoDTP represented by the general formula (2) and MoAm represented by the general formula (3) may be used alone, or two or more may be used in combination.

In the molybdenum compounds represented by the general formulas (1) to (3), R ^{1 to} R ¹⁰ are hydrocarbon groups,
For example, there are an alkyl group, an alkenyl group, an alkylaryl group, a cycloalkyl group, a cycloalkenyl group and the like.

Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, undecyl , Dodecyl, tridecyl, isotridecyl, myristyl, palmityl, stearyl, icosyl, docosyl, tetracosyl, triacontyl, 2-octyldodecyl,
2-dodecylhexadecyl, 2-tetradecyloctadecyl, monomethyl-branched-isostearyl and the like can be mentioned.

Examples of the alkenyl group include vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, pentenyl, isopentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, oleyl and the like.

Examples of the alkylaryl group include phenyl, toluyl, xylyl, cumenyl, mesityl, benzyl, phenethyl, styryl, cinnamyl, benzhydryl, trityl, ethylphenyl, propylphenyl,
Butylphenyl, pentylphenyl, hexylphenyl, heptylphenyl, octylphenyl, nonylphenyl, decylphenyl, undecylphenyl, dodecylphenyl, cumylphenyl, styrenated phenyl, α-
And naphthyl and β-naphthyl groups.

Examples of the cycloalkyl group and cycloalkenyl group include, for example, cyclopentyl, cyclohexyl, cycloheptyl, methylcyclopentyl, methylcyclohexyl, methylcycloheptyl, cyclopentenyl, cyclohexenyl, cycloheptenyl, methylcyclopentenyl, methylcyclohexenyl, methylcyclohepenyl And a thenyl group.

Note that R ⁹ and R ¹⁰ may be hydrogen atoms, but they are not hydrogen atoms at the same time.

R ^{1 to} R ¹⁰ may be the same or different. That is, R ^{1 to} R ⁴ , R ^{5 to} R ⁸ , and R ^{9 to} R ¹⁰ may be the same or different. When R ^{1 to} R ⁴ are different from each other, the lubricating oil composition has a longer drain (longer life).
It is preferable in aiming at.

Among them, R ^{1 to} R ⁴ , that is, MoD
In TC, an alkyl group having 8 to 13 carbon atoms, R ⁵ to
R ⁸ , that is, an alkyl group having 6 to 13 carbon atoms in MoDTP, and R ^{9 to} R ¹⁰ , that is, an alkyl group having 6 to 18 carbon atoms in MoAm. This is because if the number of carbon atoms is too small, the oil solubility becomes poor. If the number of carbon atoms is too large, the melting point becomes high, handling becomes poor, and the activity becomes low.

In the general formulas (1) and (2), X ^{1 to} X ^{4 and} X ^{5 to} X ⁸ each represent a sulfur atom or an oxygen atom, and X ^{1 to} X ^{4 and} X ⁵ to All of X ⁸ may be a sulfur atom or an oxygen atom, and four X ^{1 to} X ⁴ , X
^{5 to} X ⁸ may each be a sulfur atom or an oxygen atom, but in consideration of lubricity and corrosiveness, a sulfur atom /
It is particularly preferred that the ratio of oxygen atoms is 1/3 to 3/1.

The method for producing MoDTC used in the present invention is preferably, for example, the method described in JP-B-56-12638. That is, it can be obtained by reacting molybdenum trioxide or molybdate with an alkali sulfide or an alkali hydrosulfide, then adding carbon disulfide and a secondary amine and reacting at an appropriate temperature.

The MoDTP used in the present invention is described in, for example, JP-A-61-87690 and JP-A-61-106587.
The method described in the above item is preferred. That is, it can be obtained by reacting molybdenum trioxide or molybdate with an alkali sulfide or alkali hydrosulfide, and then adding P ₂ S ₅ and a secondary alcohol and reacting at an appropriate temperature.

MoAm used in the present invention is a reaction product of a hexavalent molybdenum compound such as molybdenum trioxide, molybdic acid (H ₂ MoO ₄ ), molybdate and a salt of a primary or secondary amine. So, for example,
It is preferably produced by the method described in US Pat. That is, molybdenum trioxide or a molybdate and a primary or secondary amine are reacted at room temperature to 100 ° C.
Between them.

The molybdenum compound as the component (A) of the present invention may be one of MoDTC, MoDTP and MoAm, or two or more of them may be used in combination.
Preferably, the species uses MoDTC. The amount of addition is not particularly limited, but if the amount is too small, the effect of reducing friction is not sufficient, and if the amount is too large, sludge and corrosion tend to be caused. Preferably 0.005 to 2% by weight, more preferably 0.01 to 1% by weight, and still more preferably 0.02% by weight.
０0.9% by weight.

[0031] In thiocarbamoyl compounds represented by the present invention component (B) is the general formula (4), R ¹¹ ~R ¹⁴ is a hydrocarbon group, which may be the same or different from each other, also the above-mentioned R ¹ to R ¹⁰ as well as, alkyl group, alkenyl group, but an alkyl aryl group or the like, the number of carbon atoms must be 6 or more. If the number of carbon atoms is less than 6, the solubility in the lubricating base oil is insufficient, which adversely affects the lubricity. Among them, preferred hydrocarbon groups are hydrocarbon groups having 8 or more carbon atoms, and more preferably alkyl groups having 8 to 13 carbon atoms. Further, if the compound is straight-chain, ligand exchange may occur with the molybdenum compound as the component (A). Therefore, a branched hydrocarbon group such as a 2-ethylhexyl group or an isotridecyl group is preferable. Therefore, the most preferred hydrocarbon group is an alkyl group having a branched chain and having 8 to 13 carbon atoms.

Y represents-(S) _n- , where n is 1
Represents the number of ~ 7. Particularly preferred as Y is when n = 1 to 3, more preferably n = 2, that is, -S
-S-.

The addition amount of the thiocarbamoyl compound as the component (B) is not particularly limited. However, if the addition amount is too small, the effect of reducing friction in deteriorated oil is not sufficient, and if the addition amount is too large, sludge and corrosion may be caused. Therefore, the content is preferably 0.001 to 3% by weight, more preferably 0.05 to 1% by weight, and still more preferably 0.1 to 0.8% by weight based on the lubricating base oil.

The metal detergent as the component (C) of the present invention is not particularly limited, and may be a commonly used metal detergent.
For example, lithium dinonyl naphthalene sulphonate,
Sodium dinonyl naphthalene sulphonate, zinc dinonyl naphthalene sulphonate, aluminum dinonyl naphthalene sulphonate, magnesium dinonyl naphthalene sulphonate, calcium dinonyl naphthalene sulphonate, barium dinonyl naphthalene sulphonate, sodium trisulphonate Benzylmethylbenzenesulfonate, potassium tribenzylmethylbenzenesulfonate, sodium-2,6-dioctylnaphthalene-
1-sulfonate, sodium-2,6-didodecylnaphthalenesulfonate, magnesium dodecyl salicylate, magnesium hexadecyl salicylate, calcium dodecyl salicylate, calcium hexadecyl salicylate, barium dodecyl salicylate, barium hexadecyl salicylate, magnesium nonylphenate, calcium nonylphenate And barium nonylphenate. Among these, metal sulfonates, metal phenates, metal salicylates are preferred,
More preferred are metal phenates and metal salicylates, and most preferred are alkaline earth metal phenates and alkaline earth metal salicylates.

The metal detergent used in the present invention includes, for example, JP-A-3-281595, JP-A-3-153794, JP-A-62-96598, JP-A-63-46297,
JP-A-62-190295, JP-A-53-12172
It is preferably manufactured by the method described in No. 7, etc.

The ashless dispersant which is the component (C) of the present invention is not particularly limited, and may be a commonly used ashless dispersant. For example, benzylamine, benzylamine boron derivative, alkenyl succinimide, alkenyl succinimide boron derivative and the like can be mentioned.

The ashless dispersant used in the present invention is preferably produced by the method described in, for example, JP-A-3-41193 and JP-A-1-95194.

The metal detergent and / or the ashless dispersant as the component (C) of the present invention may be used alone or in combination of two or more. The amount of addition is not particularly limited, but is preferably 0.001 to 15% by weight based on the lubricating base oil,
The content is more preferably 0.01 to 10% by weight, and still more preferably 0.05 to 8% by weight. If the added amount is too small, it is not desirable from the viewpoint of corrosiveness, and the abrasion increases, and the amount of generated sludge increases. On the other hand, if the amount is too large, the coefficient of friction may increase.

In order to obtain more excellent lubricity,
It is preferable to further add the component (D) in addition to the components (A), (B) and (C). In the ZDTP represented by the general formula (5), which is the component (D) of the present invention, R ¹⁵ and R ¹⁶ are hydrocarbon groups, which may be the same or different from each other, and are the same as R ^{1 to} R ¹⁰ described above. , An alkyl group, an alkenyl group, an alkylaryl group and the like. Among these, an alkyl group having 3 to 14 carbon atoms is preferable.

Further, one or more ZDTs used
It is preferable that 60% or more of R ¹⁵ and R ^{16 in} P is a primary alkyl group. The remaining 40% or less may be a secondary and / or tertiary alkyl group.

Further, a is 0 to 1/3, and when a = 0, it is called neutral ZDTP, and when a = 1/3, it is called basic ZDTP.

The ZDTP used in the present invention can be produced, for example, by the method described in JP-B-48-37525. That is, it is produced by reacting P ₂ S ₅ with a desired alcohol to produce an alkyl-substituted dithiophosphoric acid, neutralizing or basifying it with zinc oxide, and forming a zinc salt.

[0043] Further, in ZDTC represented by the general formula is a component (D) of the present invention (6), R ¹⁷ ~R ²⁰ is a hydrocarbon, it may be the same or different from each other, also the above-mentioned R ¹ to R ¹⁰ as well as, alkyl group, alkenyl group, and alkyl aryl group. Among these, an alkyl group having 3 to 14 carbon atoms is preferable.

The ZDTC used in the present invention can be produced, for example, by the method described in Japanese Patent Publication No. 7-80833. That is, it is produced by heating and mixing zinc oxide, amine and carbon disulfide.

The component (D) of the present invention, ZDTP, and / or
Alternatively, one kind of ZDTC may be used alone, or two or more kinds may be used in combination. The addition amount is not particularly limited, but if the addition amount is too small, a sufficient extreme pressure effect cannot be obtained, and if the addition amount is too large, ZDTP contains phosphorus, which tends to poison the catalyst of the exhaust gas treatment device. Therefore, the content is preferably 0.01 to 10% by weight, more preferably 0.05 to 5% by weight, based on the lubricating base oil.

The lubricating base oil that can be used in the present invention may be any of mineral oil and synthetic oil. The kinematic viscosity is not particularly limited, but is preferably 0.1 to 50 at 100 ° C.
cSt, about 1 to 1,000 cSt at 40 ° C., and a viscosity index (VI) of preferably 70 or more, more preferably 100
That is all.

Here, mineral oil is separated from natural crude oil,
Distilled, purified, paraffinic, naphthenic, or hydrogenated and solvent purified,
And hydrocracked VHVI oils. The synthetic oil is a chemically synthesized lubricating oil, and is a poly-α-olefin, polyisobutylene (polybutene), diester, polyol ester, phosphate ester, silicate ester, polyalkylene glycol, polyphenyl ether. , Silicones, fluorinated compounds, alkylbenzenes and the like.

If necessary, various known additives such as higher fatty acids, higher alcohols, amines, amides, esters, polyol ethers and the like may be used within the scope of the present invention.
Friction modifiers such as polyethers, extreme pressure agents such as sulfur-based, chlorine-based, phosphorus-based and organometallics, antioxidants such as phenols and amines, and high molecular weight poly (meth) acrylates;
Viscosity index improvers such as polyisobutylene, polystyrene, ethylene-propylene copolymer, styrene-isobutylene copolymer, etc., or defoamers such as esters and silicones, other rust inhibitors, pour point depressants, etc. Can be added in the range of the amount used.

The lubricating oil composition of the present invention can be used for lubrication in all applications. For example, industrial lubrication oil, turbine oil, machine oil, bearing oil, compressor oil, hydraulic oil, hydraulic oil, internal combustion engine oil, gear oil, automatic transmission oil, transaxle fluid,
Metal working oils and the like. Among them, vehicle engines,
The composition is suitable for internal combustion engine oils such as two-cycle engines, aircraft engines, marine engines, and locomotive engines. Examples of the internal combustion engine include a gasoline engine, a diesel engine, a jet engine, a gas turbine engine, an alcohol engine, and the like.

[0050]

EXAMPLES Hereinafter, the lubricating oil composition of the present invention will be described in more detail by way of examples. EXAMPLES The components used in the lubricating oil compositions of the present invention and comparative products are as follows: Lubricating base oil: a mineral oil-based high VI obtained by hydrocracking a mineral oil obtained from crude oil oil. Kinematic viscosity is 100 ° C
4.1 cSt, 18.3 cSt at 40 ° C., VI = 12
6.

<Component (A)> Mo compound 1: In the general formula (1), R ^{1 to} R ⁴ = 2-
An ethylhexyl group, M wherein X ^{1 to} X ⁴ = S / O = 2.2
oDTC. Mo compound 2: In the general formula (1), R ^{1 to} R ⁴ = 2-
Ethylhexyl group: isotridecyl group = 1: 1, X ¹ to
MoDTC where X ⁴ = S / O = 2.2. Mo compound 3: In the general formula (2), R ^{5 to} R ⁸ = 2-
An ethylhexyl group, M wherein X ^{5 to} X ⁸ = S / O = 2.2
oDTP. Mo compound 4: a compound of the general formula (3) synthesized by the following method. Under a nitrogen stream, 1 mol of molybdenum trioxide is dispersed in 540 ml of water, and then 2 mol of ditridecylamine (R ⁹ ,
R ¹⁰ = isotridecyl group) at 50 to 60 ° C.
The mixture was added dropwise for one hour and aged at the same temperature for one hour. Thereafter, the aqueous layer was separated and removed, and a light blue oily amine molybdate compound (MoAm) was synthesized.

<Component (B)> Thiocarbamoyl compound 1: In the general formula (4), R ¹¹
To R ¹⁴ = 2-ethylhexyl group, Y = -S-S- in which bis (di 2-ethylhexyl carbamoyl) disulfide. Thiocarbamoyl compound 2: In the general formula (4), R ¹¹
Bis (diisotridecylcarbamoyl) disulfide in which 14R ¹⁴ = isotridecyl group and Y = —S—S—. Thiocarbamoyl compound 3: In formula (4), R ¹¹
To R ¹⁴ = butyl, Y = -S-S- in which bis (dibutylcarbamoyl) disulfide. Thiocarbamoyl compound 4: In the general formula (4), R ¹¹
Ethylene bis (dibutylcarbamoyl) disulfide in which 14R ¹⁴ = butyl group and Y = —S— (CH ₂ ) —S—.

<Component (C)> Metal detergent 1: Calcium phenate Metal detergent 2: Calcium salicylate Metal detergent 3: Calcium sulfonate Ashless dispersant 4: Boron alkenyl succinimide Ashless dispersant 5: Alkenyl succinic acid Imide

<Component (D)> ZDTP1: In the general formula (5), R ¹⁵ and R ¹⁶ = 2-
Ethylhexyl group (primary alkyl group), neutral salt (a =
0): Basic salt (a = 1/3) = 55: 45 (molar ratio)
ZDTP. ZDTP2: ZDTP in the general formula (5), in which R ¹⁵ and R ¹⁶ = secondary hexyl group: isopropyl group = 1: 1, neutral salt: basic salt = 62: 38 (molar ratio). ZDTC3: In the general formula (6), R ^{17 to} R ²⁰ = 2-
ZDTC which is an ethylhexyl group.

By mixing the above components in the proportions shown in the table, lubricating oil compositions of the present invention and comparative products were obtained. Next, a solubility test was first performed to confirm the presence or absence of a precipitate. Thereafter, a deterioration test was performed to measure the coefficient of friction of the deteriorated lubricating oil composition. The test conditions are as follows. In addition, among the numerical values in the table, the component (A) represents ppm by weight of molybdenum relative to the lubricating base oil, and the components (B), (C) and (D) represent% by weight.

<Solubility test> Each component was added to a lubricating base oil in an amount of 80%.
The mixture was heated and dissolved at ℃, left at room temperature and confirmed after 30 days. : No precipitation ×: Precipitation occurred.

<Deterioration test> The test was carried out in accordance with JIS-K-2514. The temperature of the thermostat was 150 ° C., and the sample stirring rod was stirred at 1,300 revolutions per minute for 140 hours to oxidize and degrade the sample oil.

<Method of Measuring Friction Coefficient> With respect to the lubricating oil compositions of the present invention and the comparative product, a friction coefficient measurement test was performed using an SRV measuring test machine under the following conditions. <Conditions> Line contact: The test conditions were cylinder-on-plate line contact conditions. That is, the upper cylinder (φ15 × 22m
m) was set on a plate (φ24 × 6.85 mm) perpendicularly to the sliding direction, reciprocated and vibrated, and the friction coefficient was measured after 7 minutes. The material was SUJ-2 for both. Load: 400 N Temperature: 70 ° C. Measurement time: 15 minutes Amplitude: 1.5 mm Cycle: 50 Hz The formulations of the lubricating oil compositions of the present invention and comparative products, and the results of the measurement are shown in the following table.

[0059]

[Table 1]

From the above example, when the thiocarbamoyl compound was added, when it was not added (Comparative product 1)
The coefficient of friction is better than that of. Also, among the thiocarbamoyl compounds, the lubricating oil composition containing a compound having a short hydrocarbon chain (Comparative Product 5) and the lubricating oil composition containing a compound having a methylene group (Comparative Product 6) have the thiocarbamoyl compound as a base oil. It can be seen that the precipitate did not dissolve sufficiently in water and the coefficient of friction was not good. Further, when the metal detergent was added, the coefficient of friction was better than when the metal detergent was not added (Comparative Product 3).

[0061]

The effect of the present invention is to provide a lubricating oil composition containing a molybdenum compound, a thiocarbamoyl compound and a metal detergent. The lubricating oil composition of the present invention maintains good lubricity even after deterioration, and is particularly useful as a fuel-saving engine oil.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C10M 135: 18 133: 04 135: 10 133: 20 133: 56 137: 10) (C10M 159/18 133: 04 125: 10) C10N 10:04 10:12 30:04 30:06 40:25 60:00 (72) Inventor Yoko Saito 7-35 Higashiogu, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd. (72) Inventor Miyashita Asao Denka Kogyo Co., Ltd. (72) Inventor Kazuhisa Morita 7-35 Higashiogu Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd.

Claims (6)

[Claims] 1. A lubricating base oil having the general formula (1) as a component (A): (Wherein, R ^{1 to} R ⁴ represent a hydrocarbon group, and X ^{1 to} X
⁴ represents an oxygen atom or a sulfur atom), represented by the general formula (2): (Wherein, R ^{5 to} R ⁸ represent a hydrocarbon group, and X ^{5 to} X
⁸ represents an oxygen atom or a sulfur atom) and a hexavalent molybdenum compound represented by the following general formula (3): R ⁹ —NH—R ¹⁰ (3) , R ⁹ and R ¹⁰ represent a hydrogen atom and / or a hydrocarbon group, but are not a hydrogen atom at the same time) are selected from the group consisting of molybdenum amine compounds obtained by reacting with an amino compound represented by One or more molybdenum compounds; as the component (B), a compound represented by the general formula (4): Wherein R ^{11 to} R ¹⁴ represent a hydrocarbon group having 6 or more carbon atoms, Y represents — (S) _n —, and n represents a number of 1 to 7; And (C)
A lubricant composition comprising a metal detergent and / or an ashless dispersant as a component. 2. The lubricating oil composition according to claim 1, wherein in the general formula (2), R ^{11 to} R ¹⁴ are a branched alkyl group having 8 or more carbon atoms. 3. The metal detergent (C) is at least one selected from the group consisting of metal phenates, metal sulfonates and metal salicylates, and the ashless dispersant is alkenyl succinimide and / or alkenyl succinimide boron. 3. The lubricating oil composition according to claim 1, which is a derivative. 4. The component (A) is 0.005 to 2% by weight in terms of molybdenum and the component (B) is 0.005% by weight based on the lubricating base oil.
0.001 to 15% by weight, and 0.001 to 15% of the component (C).
The lubricating oil composition according to any one of claims 1 to 3, wherein the lubricating oil composition contains 1% by weight. Further, as the component (D), a compound represented by the general formula (5): (Where a represents a number of 0 to 1/3, and R ¹⁵ and R
¹⁶ represents a hydrocarbon group) and / or zinc dithiophosphate represented by the following general formula (6): (Wherein, R ¹⁷ to R ²⁰ represents a hydrocarbon group) containing zinc dithiocarbamate represented by the lubricating oil composition of any one of claims 1 to 4. 6. The component (D) is added to the lubricating base oil in an amount of 0.5%.
The lubricating oil composition according to claim 5, which contains from 0.01 to 10% by weight.