JP2003165991A - Lubricating oil composition for automobile engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a lubricating oil composition suitably employable particularly as a four-cycle engine oil for a motor bicycle consuming a little amount of oil and excellent in high-temperature oxidation stability and power transmitting performances. <P>SOLUTION: This lubricating oil composition comprises a mineral oil-based base oil having a lubricating viscosity and, dissolved or dispersed therein, (a) 0.01-0.08 wt.%, in terms of the boron content, of a boron-containing-succinimide- based dispersant, (b) 0.05-0.3 wt.%, in terms of the calcium content, of a calcium- containing cleaning agent, (c) 0.04-0.12 wt.%, in terms of the phosphorus content, of a zinc dialkyldithiophosphate and (d) 0.01-5.0 wt.% of an antioxidant, where the mineral oil-based base oil has a kinematic viscosity of 3-9 mm<SP>2</SP>/s at 100°C and an evaporation loss of at most 14 wt.%. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a lubricating oil composition for automobile engines, and more particularly to a lubricating oil composition suitable for lubricating a four-cycle gasoline engine for two-wheeled vehicles. In particular, the present invention relates to a four-cycle engine oil for a two-wheeled vehicle that consumes little oil and has excellent high-temperature oxidation stability and power transmission performance.

[0002]

2. Description of the Related Art Conventionally, as a four-cycle gasoline engine oil for a two-wheeled vehicle, an engine oil developed for a four-cycle gasoline engine for a four-wheeled vehicle has been generally diverted. However, unlike a four-wheeled vehicle, a two-wheeled vehicle shares the lubricating oil for the engine, the clutch system, and the transmission. It may interfere with the mechanism. Particularly in recent years, in the fuel-saving 4-cycle engine oil that has been strongly demanded for automobiles,
There is concern that clutch slippage may occur due to low friction properties and that gear durability may be insufficient due to low viscosity properties. Actually, such cases have been reported.

On the other hand, in a four-cycle gasoline engine for a two-wheeled vehicle, the oil temperature of the engine oil is likely to rise due to its features of small size, high output, high speed rotation, air cooling and / or water cooling. Therefore, there is a demand for an engine oil that consumes little oil and has excellent high-temperature oxidation stability.

[0004]

Therefore, the present invention provides a lubricating oil composition for automobile engines, which is particularly useful as a four-cycle engine oil for two-wheeled automobiles, which consumes little oil and is excellent in high temperature oxidation stability and power transmission performance. To provide.

[0005]

As a result of repeated studies on the above-mentioned problems, the present inventor has found that the oil consumption of lubricating oil (engine oil) in an engine test using a two-cycle automobile four-cycle gasoline engine and the engine oil It was found that there is a close relationship with the evaporation loss of base oil, which accounts for the major amount of. And as the base oil, the evaporation loss is 14% by weight.
And the kinematic viscosity at 100 ° C. is 3 to 9 mm ² /
It has been found that the use of the mineral oil base oil of s gives a 4-cycle gasoline engine oil composition for motorcycles, which consumes less oil, has excellent oxidation stability at high temperatures, and has excellent power transmission performance. The present invention has been reached.

The present invention is a lubricating oil composition for an automobile engine, which contains a large amount of a mineral oil-based base oil having a lubricating viscosity, wherein the mineral oil-based base oil contains (a) boron based on the total weight of the composition. The content of the succinimide-based dispersant is 0.01 to 0.08 wt% in terms of boron content, and (b) the calcium-containing detergent is 0.05 to 0.3 wt% in terms of calcium content, (c ) Zinc dialkyldithiophosphate is 0.04 to 0.12% by weight in terms of phosphorus content conversion value, and (d) is 0.01 to 5.0% by weight, respectively.
Is dissolved or dispersed, and the mineral base oil is 1
A lubricating oil composition for an automobile engine, which has a kinematic viscosity at 00 ° C. of 3 to 9 mm ² / s and an evaporation loss of 14% by weight or less.

In the present invention, the evaporation loss is the ASTM
It is a measured value obtained according to the D5800 test method.

The present invention also provides a method of lubricating a four-cycle engine for a two-wheeled vehicle using the above engine oil composition.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The base oil used in the lubricating oil composition for an automobile engine of the present invention is a mineral base oil having a lubricating viscosity and has a kinematic viscosity at 100 ° C. of 3 to 9 mm ² / s.
And the evaporation loss is 14% by weight or less.

In the present invention, the evaporation loss of the base oil is AST.
Is a measured value obtained according to the MD5800 test method,
It is preferably 12% by weight or less, particularly preferably 10%.
It is less than or equal to wt. When the evaporation loss of the base oil exceeds 15% by weight, the oil consumption and the increase in viscosity at high temperature when the engine oil using such a base oil is used in a two-wheeled vehicle remarkably increase.

The kinematic viscosity of the base oil at 100 ° C. is 4
It is preferably ˜8 mm ² / s.

Examples of such mineral oils are refined oils obtained by distilling and refining paraffinic base oils and intermediate base crude oils according to a conventional method, for example, solvent refined oils, hydrogenated refined oils, dewaxed oils. , A clay treated oil can be mentioned. In particular, hydrocracked base oil that has been subjected to advanced hydrotreating (for example, evaporation loss is 10% by weight or less, aromatic content is 10% by weight or less).
The following and base oils having a viscosity index of 120 or more) can be preferably used in the present invention. Also, a high viscosity index base oil produced by a process of isomerization and hydrocracking using a mineral oil-based slack wax (crude wax) or a synthetic wax synthesized from natural gas as a raw material is preferable because of its small evaporation loss. it can. Further, the mineral base oil of the present invention may be a mixed base oil containing at least 10% by weight of these oils. In the case of the solvent refined oil 150 neutral oil which has been conventionally used for preparing 10WXX oil such as SAE10W30, the evaporation loss is usually 15 to 20% by weight. Is desirable.

The lubricating oil composition of the present invention basically contains the above-mentioned various additives. The boron-containing succinimide-based dispersant of the component (a) in the basic component is contained in an amount of 0.01 to 0.08 wt% in terms of boron content. This boron-containing succinimide dispersant has excellent thermal oxidation stability and abrasion resistance as compared with other dispersants, and is suitable for the present invention. The boron-containing succinimide dispersant is preferably a boric acid-modified derivative of an alkenyl or alkyl succinimide, and generally has a molecular weight of 900 to
Polybutenyl succinic anhydride obtained by reacting 5000 polyolefins, especially polybutene, with maleic anhydride by a chlorination method or a thermal reaction method, and a polyalkylene polyamine having an average number of nitrogen atoms of 4 to 10 per molecule. It can be produced by subjecting the succinimide obtained by the reaction to a reaction treatment with boric acid. Although the chlorination method has a higher reaction rate than the thermal reaction method, a large amount of chlorine tends to remain in the final product (for example, about 2000 ppm).
On the other hand, in the thermal reaction method, the amount of chlorine in the final product can be suppressed to an extremely low level (for example, about 30 ppm or less), which is also preferable in relation to dioxin and the like.

Among polybutenes, highly reactive polyisobutene having a methylvinylidene structure of at least about 50% is preferable because the reaction rate can be improved even by a thermal reaction method. In this case, the amount of unreacted polybutene decreases, so that a dispersant having a high effective component (succinimide) concentration can be obtained. Therefore, a boric acid-modified derivative of succinimide produced by a thermal reaction method using highly reactive polyisobutene is particularly preferable.

The above-mentioned boron-containing succinimide dispersant is contained as an essential component in the lubricating oil composition of the present invention, but other alkenylbenzylamine-based and alkenyl succinic ester-based ashless dispersants are also appropriately used. It can be used in combination.

The calcium-containing detergent as the component (b) is used in the lubricating oil composition of the present invention in a calcium content conversion value of 0.0.
It is contained in an amount of 5 to 0.3% by weight. The calcium-containing detergent is preferably a sulfurized calcium (Ca) alkylphenate derived from a branched alkyl-substituted phenol and having a total base number of 10 to 350 mgKOH / g. Conventional engine oils that were often diverted to engine oils developed for four-cycle automobile four-cycle gasoline engines used Mg sulfonate and Ca sulfonate, but compared to these, the sulfurized Ca phenate was
It is excellent in thermal oxidation stability and in improving the frictional characteristic index and is suitable for preparing the lubricating oil composition of the present invention.

Although the above-mentioned calcium-containing detergent is contained as an essential component in the lubricating oil composition of the present invention, the other non-sulfurized alkylsalicylic acid alkali metal salt or alkaline earth metal salt, carbon-nitrogen. Alkali metal salt or alkaline earth metal salt of organic acid or phenol derivative having bond, alkali metal salt or alkaline earth metal salt of non-sulfurized alkylphenol derivative having Mannich base structure, and alkali metal salt of petroleum sulfonic acid or alkylbenzene sulfonic acid Metallic detergents such as salts or alkaline earth metal salts can also be used in appropriate combination.

The component (c) zinc dialkyldithiophosphate is used in the lubricating oil composition of the present invention in a phosphorus content conversion value of 0.0.
It is contained in an amount of 4 to 0.12% by weight. However, considering the catalyst poisoning of the exhaust gas purification catalyst, the phosphorus content is 0.04 to
It is preferably in the range of 0.08% by weight. As the zinc dialkyldithiophosphate, zinc dialkyldithiophosphate containing a secondary alkyl group derived from a secondary alcohol having 3 to 18 carbon atoms is preferable from the viewpoint of preventing wear. On the other hand, zinc dialkyldithiophosphate containing a primary alkyl group derived from a primary alcohol having 3 to 18 carbon atoms has excellent heat resistance. Therefore,
In the lubricating oil composition of the present invention, it is preferable to use a secondary alkyl group type zinc dialkyldithiophosphate and a primary alkyl group type zinc dialkyldithiophosphate in an appropriate combination to prevent wear and thermal oxidation stability. It is more preferable from the point.

The component (d) antioxidant is contained in the lubricating oil composition of the present invention in an amount of 0.01 to 5.0% by weight. As the antioxidant, an antioxidant phenol compound and an antioxidant amine compound are preferable, and specifically, a hindered phenol-based antioxidant and a diarylamine-based antioxidant are used.

Examples of hindered phenolic antioxidants are 2,6-di-t-butyl-p-cresol,
4,4'-methylenebis (2,6-di-t-butylphenol), 4,4'-methylenebis (6-t-butyl-)
o-cresol), 4,4'-isopropylidene bis (2,6-di-t-butylphenol), 4,4'-bis (2,6-di-t-butylphenol), 2,2'-
Methylenebis (4-methyl-6-t-butylphenol), 4,4'-thiobis (2-methyl-6-t-butylphenol), 2,2'-thio-diethylenebis [3
-(3,5-di-t-butyl-4-hydroxyphenyl) propionate], octyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, and 3- (3,5- Mention may be made of hindered phenols such as octadecyl di-t-butyl-4-hydroxyphenyl) propionate. In particular, 3- (3,5
The -di-t-butyl-4-hydroxyphenyl) propionic acid alkyl ester is in a liquid state, has excellent solubility, and is favorably used in the lubricating oil composition of the present invention.

Examples of diarylamine antioxidants are mixed alkyl diphenylamines having 4 to 9 carbon atoms, p, p'-dioctyldiphenylamine, phenyl-α-naphthylamine, phenyl-β-naphthylamine, alkylated-α-naphthylamine. , And diarylamines such as alkylated-phenyl-α-naphthylamine.

The hindered phenol-based antioxidant and the diarylamine-based antioxidant can be used alone, but may be used in combination if desired. Further, oil-soluble antioxidants other than these may be used in combination.

The lubricating oil composition of the present invention may further contain 40 to 1000 ppm by weight of a molybdenum-containing compound belonging to the multifunctional additive. Molybdenum-containing compounds function as antioxidants and antiwear agents in engine oil compositions. As the molybdenum compound, imide,
A molybdenum-containing reaction product of an amide or an amine is preferable, and a sulfur-containing oxymolybdenum complex compound of succinimide (described in JP-B-3-22438) can contribute to improvement of cleanability at high temperature and is particularly preferable. . In addition, sulfurized oxymolybdenum dithiocarbamate and sulfurized oxymolybdenum dithiophosphate, which are often used in fuel-saving engine oils for four-cycle automobile 4-cycle gasoline engines, tend to reduce the friction coefficient and power transmission performance. It is not preferable because it exists.

The addition of an alkali metal borate hydrate is also effective in terms of high temperature detergency or imparting a base number. In the present invention, the alkali metal borate hydrate represents a compound represented by the compound synthesized by the method described in US Pat. Nos. 3,929,650 and 4,089,790. For example, fine particles dispersion of an alkali metal borate obtained by carbonating an alkali metal or alkaline earth metal neutral sulfonate in the presence of an alkali metal hydroxide to obtain an overbased sulfonate, and reacting this with boric acid. The body (it is desirable to coexist with an ashless dispersant such as succinimide in the carbonation reaction) can be mentioned. Here, potassium is used as the alkali metal,
Sodium is preferable. As a specific example, a particle size of about 0.3 represented by the composition formula: KB ₃ O ₅ .H ₂ O dispersed in neutral calcium sulfonate and succinimide system.
An example is a fine particle dispersion having a size of μm or less. From the viewpoint of water resistance, those in which potassium is replaced with sodium are also preferably used.

The lubricating oil composition of the present invention may contain a viscosity index improver in an amount of 20% by weight or less (particularly in the range of 1 to 20% by weight). Examples of viscosity index improvers include polyalkylmethacrylates, ethylene-propylene copolymers, styrene-butadiene copolymers, and polymeric compounds such as polyisoprene. Further, it is also possible to use a dispersion type viscosity index improver or a multifunctional viscosity index improver in which dispersion performance is imparted to these polymer compounds. These viscosity index improvers can be used alone, but any two or more kinds of viscosity index improvers may be used in combination.

Further, the lubricating oil composition of the present invention may contain various auxiliary additives. Examples of such auxiliary additives are zinc dithiocarbamate, methylenebis (dibutyldithiocarbamate), an oil-soluble copper compound, a sulfur-based compound (eg, sulfurized olefin, sulfurized ester, which functions as an antioxidant or an antiwear agent). Examples thereof include polysulfide), phosphoric acid ester, phosphorous acid ester, and organic amide compounds (eg, oleylamide). Further, a benzotriazole-based compound or a thiadiazole-based compound that functions as a metal deactivator can be added. Polyoxyethylene ethylene phenyl ether, which functions as a rust inhibitor or demulsifier
A polyoxyalkylene nonionic surfactant such as a copolymer of ethylene oxide and propylene oxide can also be added. Various amines, amides, amine salts, and their derivatives that function as friction modifiers, or fatty acid esters of polyhydric alcohols, or their derivatives can also be added. Further, various compounds that function as a defoaming agent or a pour point depressant can be added. These auxiliary additives are preferably used in amounts of 3% by weight or less (particularly in the range of 0.001 to 3% by weight) based on the lubricating oil composition.

The lubricating oil composition of the present invention obtained by dissolving or dispersing the above-mentioned various additive components in the mineral oil base oil has a SAE viscosity grade of 5W30, 5
It is preferably W40, 10W30, 10W40 or 10W50. Further, the lubricating oil composition of the present invention has a sulfated ash content of 0.2 to 1.2% by weight, a phosphorus content of 0.04 to 0.12% by weight, and a chlorine content based on the total weight of the composition. Of 40 ppm by weight or less and high temperature high shear viscosity (according to ASTM D4683 test method) of 2.9 mPa · s
The above is desirable. And, such a lubricating oil composition of the present invention is classified into MA based on JASO T903-98.

By using the above-mentioned lubricating oil composition of the present invention in a four-cycle gasoline engine for a two-wheeled vehicle, the engine can be suitably lubricated.

[0029]

EXAMPLES (1) Production of Engine Oil Composition Using the following base oil and additive components, a lubricating oil composition according to the present invention and a lubricating oil composition for comparison were produced. These lubricating oil compositions were prepared by adding a viscosity index improver so that the SAE viscosity grade was 10W30.

(2) Base oil Base oil 1: kinematic viscosity at 100 ° C. of 5.23 mm ² / s, evaporation loss (ASTM D5800) of 12.5% by weight, viscosity index of 102 solvent refined mineral oil 150 neutral oil (distillation temperature range) : Narrow cut type) Base oil 2: Kinematic viscosity at 100 ° C. 6.40 mm ² / s, Evaporation loss 5.6% by weight, Viscosity index 132 Hydrocracked mineral oil Base oil 3: Solvent refined mineral oil 100 Neutral oil (100 ° C.
Kinematic viscosity: 4.00 mm ² / s, evaporation loss 28.1% by weight, viscosity index 98), and 250 neutral oil (100
℃ kinematic viscosity: 6.59mm ² / s, evaporation loss 7.0% by weight, mixed oil weight ratio 70:30 between the viscosity index 96),
Kinematic viscosity at 100 ° C. 5.40 mm ² / s, evaporation loss 21.
7% by weight, viscosity index 98 Base oil 4: kinematic viscosity at 100 ° C. 5.30 mm ² / s, evaporation loss 18.4% by weight, solvent refining mineral oil 15 with viscosity index 106
0 neutral oil

(3) Additive component boric acid-modified succinimide dispersant: number average molecular weight of about 13
Of polyisobutenyl succinic anhydride obtained by thermally reacting highly reactive polyisobutene of 00 (having a methylvinylidene structure of 50% or more) and maleic anhydride with an average number of nitrogen atoms of 6.5 (1 molecule Per bis type succinimide obtained by reacting with polyalkylene polyamine (reaction of nitrogen content 2.0% by weight, boron content 0.7% by weight, chlorine content less than 5 ppm)

Sulfurized Calcium Phenate Detergent: Sulfurized Ca alkylphenate derived from phenol alkylated with propylene tetramer (Ca: 9.3 wt%, S: 3.4 wt%, TBN 255 mg KOH / g) Calcium sulphonate detergent Agent: (Ca: 15.5% by weight, S: 2.0% by weight, TBN: 325 mgKOH /
g, OLOA247Z manufactured by Chevron Oronite Co., Ltd.)

Zinc dithiophosphate 1: Zinc dialkyldithiophosphate derived from a secondary alcohol having 3 to 8 carbon atoms (P: 7.2% by weight, Zn: 7.85% by weight,
S: 14.4% by weight) Zinc dithiophosphate 2: Zinc dialkyldithiophosphate derived from a primary alcohol having 8 carbon atoms (P: 7.
3% by weight, Zn: 8.4% by weight, S: 14.0% by weight)

Phenolic compound antioxidant 1: 4, 4 '
-Methylenebis (2,6-di-t-butylphenol) phenolic compound antioxidant 2: 3- (3,5-di-t)
-Butyl-4-hydroxyphenyl) octylamine propionate compound antioxidant: dialkyldiphenylamine (nitrogen content 4.6% by weight, TBN 180 mgKOH /
g, an alkyl group: a mixture of C ₄ and C ₈ )

Molybdenum compound 1: Sulfur-containing oxymolybdenum-succinimide complex compound (Mo: 5.4% by weight, S: 3.7% by weight, TBN: 45 mgKOH / g) Molybdenum compound 2: Sulfurized oxymolybdenum dithiocarbamate ( Mo: 4.5% by weight, S: 4.7% by weight, alkyl group: mixture of C ₈ and C ₁₃ primary alkyl) Alkali metal borate hydrate: fine particle dispersion of potassium borate hydrate (K: 8.3% by weight, B: 6.8% by weight,
TBN: 125mgKOH / g, chevron oronite
OLO9750 manufactured by Co., Ltd.) Viscosity index improver: non-dispersion type ethylene-propylene copolymer Other additives: pour point depressant, defoaming agent

(4) Performance Evaluation of Engine Oil Composition 1) High Temperature Oxidation Engine Test A high temperature oxidation stability was tested and evaluated using an air-cooled, single-cylinder, 4-cycle gasoline engine for motorcycles with a displacement of 100 cc. . Engine oil filling amount 1400
After operating for 24 hours under the conditions of ml, oil temperature 150 ° C., engine speed 8000 rpm, and full load operation, the viscosity increase rate (%) and oil consumption amount (g / hour) of the test oil were determined.

2) Friction characteristic evaluation test SAE No. 2 friction test was conducted in accordance with JASO T904-98 motorcycle four-cycle gasoline engine oil clutch friction characteristic evaluation test method to obtain a dynamic friction characteristic index (D).
FI), static friction characteristic index (SFI) and braking time index (STI) were obtained. And J
ASO T903-98 Standard value defined as performance MA of motorcycle 4-cycle gasoline engine oil (DFI
The power transmission performance was evaluated based on 1.45 or more, SFI 1.15 or more, STI 1.55 or more).

[Examples 1 to 3] Table 1 shows the additive components in the base oil.
The engine oil composition of the present invention was produced by adding it in the composition shown in.

[Comparative Examples 1 to 3] Table 1 shows the additive components in the base oil.
Was added in the formulation shown in to prepare an engine oil composition for comparison. Table 1 shows the composition, analysis value and evaluation test result of each lubricating oil composition.

[0040]

[Table 1]

[0041]

[Table 2]

From Table 1, it can be seen that when a base oil having a high evaporation loss is used, the oil consumption amount in the engine test increases and the viscosity increase also increases. That is, when the base oil 3 (mixture of 100 neutral oil and 250 neutral oil) having a wide distillation temperature range was used (Comparative Example 1,
3) The evaporation loss was high, the viscosity was remarkably increased, and the oil consumption was also increased. Even with the base oil 4 (150 neutral oil) (Comparative Example 2), since the evaporation loss was high, the viscosity increased greatly and the oil consumption was large. on the other hand,
When Narrow cut type base oil 1 is used (Example 1,
In 3), the evaporation loss was low, the increase in viscosity and the oil consumption were suppressed. Especially, the viscosity index is high and the evaporation loss is 10
When the hydrocracking base oil 2 as low as less than wt% was used (Example 2), the increase in viscosity and the oil consumption were small.

Further, among the molybdenum compounds as additive components, a sulfurized oxymolybdenum dithiocarbamate (molybdenum compound 2), which is used as a multifunctional additive in fuel-saving gasoline engine oils for four-wheeled vehicles, is used in a friction characteristic evaluation test. It was found that there is a tendency to reduce the frictional characteristic index, and thereby reduce the power transmission performance. On the other hand, it was found that the sulfur-containing oxymolybdenum-succinimide complex compound (molybdenum compound 1) can be suitably used for a four-cycle engine oil for motorcycles without lowering the friction characteristic index.

[0044]

INDUSTRIAL APPLICABILITY The lubricating oil composition for an automobile engine of the present invention is suitable for a four-cycle engine oil for a two-wheeled vehicle because it has a small increase in viscosity at a high temperature and a small oil consumption amount and exhibits excellent high-temperature oxidation stability. used. Also, JA
A lubricating oil having a sufficiently high friction characteristic index and excellent power transmission performance, which is classified as MA based on SOT903-98.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) C10M 133/56 C10M 133/56 135/30 135/30 137/10 137/10 A 139/00 139/00 A 159/18 159/18 159/22 159/22 // C10N 10:04 C10N 10:04 10:12 10:12 20:00 20:00 AZ 20:02 20:02 30:08 30:08 30 : 10 30:10 40:25 40:25 F-term (reference) 4H104 AA26 BB05 BF03 BH07 DA02 EA02 EA04 EA21A EA21Z EA22 EB05 EB07 EB09 FA02 FA06 LA02 LA03 LA04 LA05 PA41

Claims (10)

[Claims] 1. A lubricating oil composition for an automobile engine, which comprises a large amount of a mineral oil-based base oil having a lubricating viscosity as a component, wherein the mineral oil-based base oil contains (a) a boron-containing amber based on the total weight of the composition. Acid imide dispersant is 0.01 in terms of boron content conversion
~ 0.08% by weight, (b) the calcium-containing detergent is 0.05 to 0.3% by weight in terms of calcium content, (c)
Zinc dialkyldithiophosphate had a phosphorus content converted value of 0.
04-0.12% by weight, and (d) the antioxidant is 0.
Each of which is dissolved or dispersed in an amount of 01 to 5.0% by weight, and the mineral base oil has a kinematic viscosity at 100 ° C. of 3 to 9 mm ² / s and an evaporation loss (ASTM D5800). ) Is 14% by weight or less, a lubricating oil composition for an automobile engine. 2. The mineral base oil has an evaporation loss of 10% by weight or less, an aromatic content of 10% by weight or less, and a viscosity index of 12.
The lubricating oil composition for an automobile engine according to claim 1, containing 10% by weight or more of a mineral oil of 0 or more. 3. A mineral oil base oil having an evaporation loss of 10% by weight or less, an aromatic content of 10% by weight or less, and a viscosity index of 12.
The lubricating oil composition for an automobile engine according to claim 2, which is composed of a mineral oil of 0 or more. 4. A sulfated ash content of 0.2 to 1.2% by weight, a phosphorus content of 0.04 to 0.12% by weight, and a chlorine content of 4
0 wt ppm or less, and high temperature high shear viscosity (A
The lubricating oil composition for an automobile engine according to claim 1, wherein STM D4683) is 2.9 mPa · s or more. 5. SAE viscosity grade is 5W30, 5W4
The lubricating oil composition for an automobile engine according to claim 1, which is 0, 10W30, 10W40 or 10W50. 6. A boron-containing succinimide dispersant,
Chlorine content obtained by reacting polyisobutenyl succinic anhydride obtained by thermally reacting highly reactive polyisobutene having at least about 50% methylvinylidene structure with maleic anhydride with polyalkylene polyamine Is a boric acid-modified derivative of succinimide in an amount of 30 ppm by weight or less, and the lubricating oil composition for an automobile engine according to claim 1. 7. A calcium-containing detergent derived from a branched alkyl-substituted phenol, having a total base number of 10-3.
The lubricating oil composition for an automobile engine according to claim 1, which is 50 mgKOH / g of a sulfurized calcium alkylphenate. 8. The method according to claim 1, wherein the molybdenum-containing reaction product of imide, amide or amine is further dissolved or dispersed in the mineral base oil in an amount of 40 to 1000 ppm by weight in terms of molybdenum content conversion value. Lubricating oil composition for automobile engines. 9. The lubricating oil composition for an automobile engine according to claim 1, which is for lubricating a four-cycle engine for a two-wheeled automobile. 10. A method of lubricating a four-cycle engine for a two-wheeled vehicle with the engine oil composition according to any one of claims 1 to 8.