WO2018078434A1

WO2018078434A1 - Lubricating oil composition

Info

Publication number: WO2018078434A1
Application number: PCT/IB2017/001299
Authority: WO
Inventors: 貴文森; 剛久佐藤; 崇裕福水; 小川　仁志; 純一西ノ園
Original assignee: エクソンモービルリサーチアンドエンジニアリングカンパ二ー
Priority date: 2016-10-27
Filing date: 2017-10-27
Publication date: 2018-05-03
Also published as: EP3533857A1; US20200071634A1; SG11201903317QA; JP6962677B2; JP2021155740A; JP2018070721A

Abstract

The first purpose of the present invention is to provide a lubricating oil composition which achieves extended anti-shudder durability without causing a decrease in the metal-to-metal friction coefficient, even when the viscosity of the composition is reduced. Provided is a lubricating oil composition characterized by comprising (A) a lubricant base oil, (C) (C-1) a succinimide compound or boronated succinimide compound having a weight-average molecular weight of 4,000 to 7,000, (C-2) a succinimide compound or boronated succinimide compound having a weight-average molecular weight of more than 7,000 to 10,000, and (D) a phosphorus-based extreme pressure agent, wherein the lubricating oil composition does not include zinc dithiophosphate and may optionally include a sulfur-based extreme pressure agent, provided that the content of sulfur-based extreme pressure agent is no more than 0.1 percent by weight of the lubricating oil composition.

Description

Specification

Title of invention: Lubricating oil composition

Technical field

[0001] The present invention relates to a lubricating oil composition, and particularly to a lubricating oil composition characterized by being suitably used in an automobile transmission. More specifically, the present invention relates to a lubricating oil composition for a continuously variable transmission.

Background art

[0002] Lubricating oil compositions are widely used in the automotive field such as for internal combustion engines, automatic transmissions, and gear oils. In recent years, there has been a demand for lowering the viscosity of lubricating oil compositions in order to achieve fuel economy. A continuously variable transmission (CTV) has been widely used instead of a stepped automatic transmission, and a metal bell-type CVT using a metal belt and pulley for power transmission is common.

[0003] One way to improve the fuel efficiency of continuously variable transmission vehicles is to increase the operating conditions of the lock-up clutch, and it is required to extend the anti-shudder life of the lock-up clutch. However, if the amount of friction modifier is increased to extend the anti-shudder life, the coefficient of friction between metals between the metal belt and the pulley decreases, resulting in a problem that the belt grip performance decreases and the torque transmission capacity decreases. As described above, the anti-shudder performance and the friction coefficient between metals are in a relation of high load-off, and it is required to achieve both sufficient torque characteristics and anti-shudder performance at a high level. When the viscosity of the lubricating oil composition for a transmission is lowered, there is also a problem that a sufficient intermetallic friction coefficient cannot be obtained and a sufficiently large torque cannot be secured.

[0004] For example, Patent Documents 1 to 5 describe conventional lubricating oil compositions for continuously variable transmissions. Japanese Patent Application Laid-Open No. 2 0 6-0 0 5 6 9 3 4 (Patent Document 1) discloses that a specific succinic acid compound containing no boron and a phosphorus compound are blended, and a dialkyl zinc diphosphate A lubricating oil composition that does not contain any oil is described, the coefficient of friction between the metal belt or chain and the pulley is remarkably improved, and high friction over a long period of time. The friction coefficient can be maintained and the clutch plate is not clogged. Japanese Unexamined Patent Publication No. 2007-126541 (Patent Document 2) discloses a lubricant composition containing a sulfonate detergent, a salicylate detergent, and a boron-containing succinic acid imide additive in a specific amount and a specific amount ratio. It describes that it has sufficient torque transmission capacity and speed change characteristics and is excellent in anti-shudder performance. JP 2009-2 15395 A (Patent Document 3) has a boronated alkyl succinic acid imide and / or a boronated alkenyl succinic acid imide having a specific weight average molecular weight, and a linear alkyl group. A lubricating oil composition containing a specific amount of a metallic detergent is described, and it has a high coefficient of friction between metals, and is excellent in transmission characteristics and anti-shudder performance. Japanese Patent Laid-Open No. 201 0-1 80278 (Patent Document 4) discloses a lubricating oil composition in which a specific amount of a specific sulfolane derivative, one or more selected from calcium sulfonate and calcium phenate, and a specific viscosity index improver are combined. It describes that it has a high metal friction coefficient, and achieves both fuel efficiency and component durability through low viscosity. Japanese Patent Application Laid-Open No. 2000-355695 (Patent Document 5) discloses that at least four kinds of additives, calcium salicylate, phosphorus-based antiwear agent, friction modifier, and dispersion type viscosity index improver, are blended as essential components. It states that a high coefficient of friction between metals and anti-shudder properties can be achieved at the same time.

Prior art documents

. Afternoon offering

Patent Document 1: Japanese Unexamined Patent Publication No. 2006-056934

Patent Document 2: JP 2007-1 2654 1

Patent Literature 3: Japanese Patent Publication No. 2 1395

Patent Document 4: Japanese Patent Laid-Open No. 201 0-1 80278

Patent Document 5: Opening 2000-355695

Summary of the Invention

Problems to be solved by the invention [0006] In view of the above circumstances, the first object of the present invention is to provide a lubricating oil composition having an extended shudder prevention life without lowering the coefficient of friction between metals even when the viscosity is lowered. And

Means for solving the problem

[0007] As a result of further investigations by the inventors, as an ashless dispersant, two types of succinic acid compounds or boronated succinic acid compounds having a specific mass average molecular weight are combined, and phosphorous is further added. It has been found that the combined use of an extreme pressure agent can extend the anti-shudder life without lowering the coefficient of friction between metals even when the viscosity is lowered, and the present invention has been achieved.

[0008] That is, the present invention

(A) Lubricating base oil,

(C) (C 1 1) succinic acid imide compound or borated succinic acid imide compound having a mass average molecular weight of 4, 0 0 0 to 7, 0 0 0,

(C 1 2) succinic acid imide compound or boronated succinic acid imide compound having a mass average molecular weight of more than 7,00 to 1,0,000, and

(D) A lubricating oil composition comprising a phosphorus-based extreme pressure agent, wherein the lubricating oil composition does not contain zinc dithiophosphate, and may optionally contain a sulfur-based extreme pressure agent, However, in the lubricating oil composition, the content of the sulfur-based extreme pressure agent is 0.1% by mass or less in the lubricating oil composition.

[0009] Further, in order to improve fuel consumption, it is necessary to reduce the viscosity at low temperature (eg 4 CTC) that affects fuel consumption while maintaining the viscosity at a high temperature (eg 100 ° C) as much as possible. Although a high viscosity index is required, the conventional continuously variable transmission lubricating oil composition breaks the polymer chain of the base oil and viscosity index improver due to mechanical shearing, leading to a decrease in high-temperature viscosity with running. There's a problem.

[0010] The present inventors have further identified the constitution of the lubricating base oil and the viscosity index improver in the lubricating oil composition, thereby improving the anti-shoulder life without reducing the intermetallic friction coefficient. In addition to the above, it was found that shear stability can be improved. That is, the present invention further includes

(A) Lubricating base oil,

(C) (C 1) Succinic acid imide compound or boronated succinic acid imide compound having a mass average molecular weight of 4,000 to 7,000,

(C-1) succinic acid imide compound or boronated succinic acid imide compound having a mass average molecular weight of more than 7,000 to 10,000, and

(D) A lubricating oil composition comprising a phosphorus-based extreme pressure agent, wherein the lubricating oil composition does not contain zinc dithiophosphate and may optionally contain a sulfur-based extreme pressure agent, However, the content of the sulfur-based extreme pressure agent is 0.1 mass% or less in the lubricating oil composition,

As part or all of the component (A), a poly α-age olefin or α-age olefin copolymer having kinematic viscosity SS Omm ² , s at 100 ° C is added to the mass of the entire lubricating oil composition. With respect to 5 to 30% by mass, and

(Iii) Provided is a lubricating oil composition further comprising polymethacrylate having a weight average molecular weight of 15,000 to 40,000.

Furthermore, a preferred embodiment of the lubricating oil composition of the present invention has at least the following features (1) to (10).

Part or all of the (1) (C-1) component and (C1-2) component are boronated succinimide compounds.

(2) The component (C-1) and the component (C1-2) are each composed of 0.1 to 3 masses of boron with respect to the mass of the component (C-1) or the component (C1-2). % Content.

(3) The succinic acid imide compound is represented by the following formula (1) or (2). [Chemical 1]

[Chemical 2]

In the above formula, R ¹ is independently an alkyl group or alkenyl group having 40 to 400 carbon atoms, m is an integer of〗 to 20, and n is an integer of 0 to 20.

(4) Kinematic viscosity at 100 ° C. 3 to 1 Omm ² Zs.

(5) It has a viscosity index of 150 or more.

(6) (D) The phosphorus extreme pressure agent is selected from acidic phosphoric acid ester, acidic phosphorous acid ester, phosphoric acid ester, phosphorous acid ester, and their amine salts, phosphoric acid, and phosphorous acid At least one or more.

(7) (D) the phosphorus extreme pressure agent is at least one selected from acidic phosphoric acid ester, acidic phosphorous acid ester, phosphoric acid ester, phosphorous acid ester, and amine salts thereof; It is a combination with at least one selected from acid and phosphorous acid.

(8) Further, (E) contains a metal detergent.

(9) Further, (F) an ether sulfolane compound is contained.

(1 0) For continuously variable transmissions. [0012] In particular, the lubricating oil composition comprises a poly α-age olefin having a kinematic viscosity of 6 to 80 mm ² / s at 100 ° C as part or all of the component (A). It is preferable that the α-aged lefin copolymer is contained in an amount of 5 to 30% by mass with respect to the total mass of the lubricating oil composition, and (ii) an ether sulfolane compound. Synthetic base oils have a lower affinity with oil seal rubbers called packings and gaskets than mineral oils, and the higher the molecular weight (high viscosity) base oil, the lower the affinity. If the affinity is low, the swelling of the seal rubber is reduced, and conversely, it tends to shrink. As a result, there is a problem that the sealing performance is lowered and oil leakage occurs. By making the lubricating oil composition of the present invention such a structure, the swelling property of the seal rubber can be further ensured.

The invention's effect

[0013] The lubricating oil composition of the present invention can extend the anti-shudder life without lowering the coefficient of friction between metals. This effect can be achieved even when the kinematic viscosity of the lubricating oil composition at 100 ° C. is lowered to about 5.0. Moreover, according to the present invention, in addition to the effect, a lubricating oil composition having improved shear stability can be provided. Furthermore, the swelling property of the seal rubber can be ensured. The lubricating oil composition of the present invention can be particularly suitably used as a lubricating oil composition for continuously variable transmissions.

BEST MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, each component will be described.

[0015] (A) Lubricating base oil

As the lubricating base oil in the present invention, a conventionally known lubricating base oil can be used, and there are mineral oil, synthetic oil, or a mixed oil thereof. In particular, as a part or all of the lubricating base oil, a poly α-age olefin or α-age olefin copolymer having a kinematic viscosity of 6 to 8 O mm ² / s at 100 ° C. preferably contains 5-3 0% by weight relative to the lubricating oil composition total weight, and more preferably, the lower limit is 6 mass%, good Ri preferably 8 mass%, the upper limit is 2 5 mass ^_0/0 More preferably, it is 20% by mass. If the content of the base oil is less than the lower limit, a sufficient viscosity index, that is, In other words, it is not possible to achieve both fuel saving performance and protection performance for machine elements, and if the above upper limit is exceeded, there is a risk that the shear stability will deteriorate and the rubber compatibility will deteriorate (rubber shrinkage).

[0016] The poly α-year-old refin and α-year-old olefin copolymer should have a kinematic viscosity of 6-8 Omm ² / s at 100 ° C, preferably 8-80 mm ² Z s. More preferably, it is 8-60 mm < ² > / s, More preferably, it is 9-40 mm <2> / s. If the kinematic viscosity at 100 is less than the above lower limit value, the viscosity index, that is, the fuel efficiency and the protection performance to the machine element cannot be achieved at the same time. Unfavorable because shear stability and rubber compatibility deteriorate (rubber shrinkage).

[0017] The poly α-year-old refin or α-year-old refin copolymer is a (co) polymer or (co) oligomer of α-year-old refin, and may have any of the above kinematic viscosities. Conventionally known oils can be used. The α-year-old refin is, for example, selected from linear or branched refin hydrocarbons having 2 to 14 carbon atoms, preferably 4 to 12 carbon atoms. Examples thereof include 1-year-old kuten oligomers, 1-decene oligomers, ethylene monopropylene oligomers, isobutene oligomers and hydrides thereof. Further, the poly α-age olefin or α-age olefin copolymer may be one produced using a meta-octane catalyst. The (co) polymer or (co) oligomer may have a mass average molecular weight as long as the kinematic viscosity at 100 ° C. satisfies the above range. For example, it has a mass average molecular weight of 1,000 to 10,000, preferably 1,100 to 7,000. The poly α-age olefin or α-age olefin copolymer may be used alone or in combination of two or more.

[0018] The lubricating oil composition of the present invention may contain another lubricating base oil in combination with the poly α-age olefin or α-age olefin copolymer. These lubricating base oils are not particularly limited, and conventionally known mineral base oils and synthetic base oils other than the above-mentioned poly α-age olefins and α-age olefin copolymers can be used.

CO019] Mineral oil base oil includes a lubricating oil distillate obtained by atmospheric distillation and vacuum distillation of crude oil. The paraffin-based, naphthenic-type, etc. were refined by appropriately combining the solvent desolvation, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrotreating, sulfuric acid washing, clay treatment, etc. Examples include lubricating base oils and lubricating base oils obtained by isomerizing and dewaxing waxes obtained by solvent dewaxing. The kinematic viscosity of the mineral oil base oil is not limited to waiting, but in order to obtain a lubricating oil composition having a low viscosity, it is preferably 1 to 5 mm ² Zs.

[0020] As the synthetic base oil, isoparaffin, alkylbenzene, alkylnaphthalene, monoester, diester, polyol ester, polyoxyalkylene glycol, dialkyldiphenyl ether, polyphenyl ether, GT L base oil and the like can be used. The kinematic viscosity of the synthetic base oil is not particularly limited. It is also possible to use 1 00 ° kinematic viscosity at C is less than 6 mm ² / s or 80 mm ^2, s than a is poly α- old olefin or α- old olefin copolymer. In order to obtain a lubricating oil composition having a low viscosity, the kinematic viscosity of the synthetic base oil is preferably 1 to 6 mm ² / s.

[0021] The base oils that can be used in combination may be used alone or in combination of two or more. When using two or more types, use two or more mineral base oils, use two or more synthetic base oils, and use one or more mineral base oils and one or more synthetic base oils. Can be used. Among them, use of mineral base oil alone, use of two or more mineral base oils, use of synthetic base oil with a kinematic viscosity at 100 ° C of less than 1-6mm ² / s, 100 ° C It is preferable to use two or more synthetic base oils having a kinematic viscosity of 1 to less than 6 mm ² / s.

[0022] In addition, in order to obtain a lubricating oil composition having a low viscosity, the entire lubricating base oil may have a kinematic viscosity at 100 ° C of 2 to 7 mm ² / s, preferably 2.3-6. It is preferable to have mm ² / s, particularly ^{2.5 to} 5.6 mm ² / s.

[0023] (B) Viscosity index improver

The lubricating oil composition of the present invention can contain a conventionally known viscosity index improver. Preferably, polymethacrylate relay having a weight average molecular weight of 15,000 to 40,000 is preferably included as a viscosity index improver. Mass average molecular weight The lower limit of is preferably 1 7, 0 0 0, more preferably 1 8 0 0 0 0. The upper limit of the mass average molecular weight is preferably 38,00,0, more preferably 36,000. When the mass average molecular weight is less than the lower limit, the effect of improving the viscosity index is insufficient, and when the mass average molecular weight exceeds the upper limit, the effect of improving the viscosity index can be obtained, but the shear stability It is not preferable because the properties deteriorate. Although the content of the polymethacrylate is not limited, it is preferably 0.1 to 20% by mass, more preferably 1 to 15% by mass, and still more preferably 2 to 10% by mass in the lubricating oil composition. .

[0024] Polymethacrylate may be used alone or in combination of two or more. Content in the case of using 2 or more types together is not limited. The total content of polymethacrylate-soot is preferably 0.1 to 20% by mass in the lubricating oil composition, more preferably 1 to 15% by mass, and still more preferably 2 to 10% by mass.

[0025] The lubricating oil composition of the present invention may contain other viscosity index improvers in addition to the polymethacrylate relay. Such other viscosity index improvers include polymethacrylates having a weight average molecular weight of less than 15 000, polymethacrylates having a weight average molecular weight of more than 40,000, polyisobutylene and water thereof. Additives, styrene-monohydrogenated copolymers, styrene-maleic anhydride copolymers and polyalkylstyrenes. When the other viscosity index improver is included, the blending amount is preferably an amount of 0.1 to 15% by mass in the lubricating oil composition.

[0026] (C) Succinic acid imide compound or boronated succinic acid imide compound

The lubricating oil composition of the present invention is characterized by containing two kinds of specific succinic acid imide compounds or boronated succinic acid imide compounds as ashless dispersants. That is, the present invention provides a succinic acid composition in which the lubricating oil composition has (C-1) weight average molecular weight 4, 0 00 to 7, 0 0 0, preferably 5, 0 0 0 to 7, 0 0 0. And a boron compound or a boronated succinic acid imide compound, and (C 1 2) weight average molecular weight of more than 7,00 to 1,0,0,0, preferably 7,10,0 to 9,600, It is characterized by containing a combination of existing succinic acid compounds or boronated succinic acid compounds. In the following, the above (C 1 1) component is It is called a succinic acid imide compound, and the above (C-12) component is sometimes referred to as a second succinic acid imide compound. At least one of the component (C1-1) and the component (C1-2) may be a part or all of a boronated succinic acid imide compound. Further, both (C 1 1) component and (C-2) component may be a boronated succinic acid imide compound.

[0027] The component (C) is preferably 0.5 to 3% by mass, more preferably 0.6 to 2.5% by mass, and still more preferably 0.9 to 2% by mass, based on the entire composition. Contained in the composition in an amount of. If it is less than the lower limit, it may not be possible to secure anti-shudder. Above the upper limit, the viscosity at low temperatures may be high

[0028] The mass ratio of the (C 1 1) component to the (C 1 2) component is not limited, but (C 1 2) (C 1 1) = 1 to 10 is preferable, and 1.5 -8 are more preferable, and 2-6 are more preferable. By containing it in a ratio that falls within the above range, it is possible to achieve both the friction coefficient and the shudder characteristics. If the amount ratio of (C 1 2) exceeds the above upper limit, the amount of (C-1) component is too small, and the characteristics at low temperatures, for example, 40 ° C, are insufficient for preventing shudder. A problem arises that it becomes apparent at an early stage. If the amount ratio of (C 1 2) is less than the above lower limit, there is a problem that the characteristics at high temperatures, for example, 120 ° C., are insufficient, and are manifested early in the durability test.

[0029] The first and second succinic acid imide compounds in the present invention may be succinic acid imide compounds or boronated succinic acid imide compounds known as ashless dispersants. A boronated succinic acid imide compound is obtained by modifying (borating) a succinic acid imide compound having at least one alkyl group or alkenyl group in a molecule with a boron compound such as boric acid or borate. Is mentioned. Examples of the alkyl group or alkenyl group include olefins such as propylene, 1-butene and isopylene, or oligomers thereof, and ethylene and propylene co-oligomers.

[0030] The succinic acid imide compound is more specifically, succinic anhydride is added to the polyamine. It is an added compound. There are mono-type succinic acid imide compounds and bis-type succinic acid imide compounds, both of which can be used. The monotype succinic acid imide compound can be represented by, for example, the following formula (1). The bis-type succinic acid imide compound can be represented, for example, by the following formula (2).

[Chemical 3]

[Chemical 4]

In the above formula, R ′ is independently an alkyl group or an alkenyl group having 40 to 40 carbon atoms, m is an integer from〗 to 20 and n is an integer from 0 to 20; A bis-type succinic acid imide compound is particularly preferable. The succinic acid imide compound may be a combination of monotype and bistype, a combination of two or more monotypes, or a combination of two or more bistypes.

[0031] The boronated succinic acid imide compound is a compound obtained by reacting a succinic acid imide compound represented by the above formula with a boron compound. Boron compounds include boric acid, boric anhydride, boric acid ester, boron oxide, and boron halide. The boronated succinic acid imide compound may be a single type or a combination of two or more types.

[0032] In the lubricating oil composition of the present invention, the first and second succinic acid imide compounds are Each may be part or all of a boronated succinic acid imide compound. In other words, the first and second succinic acid imide compounds in the present invention are independent of each other, and are singly or in combination of non-borated succinic acid imide compounds, fluorinated succinic acid imides. The compound may be any one selected from the group consisting of a single compound or two or more compounds, and a combination of one or more non-borated succinic acid compounds and one or more boronated succinic acid compounds. In each of the component (C1-1) and the component (C-2), the ratio of the boronated succinic acid imide compound is not particularly limited, but is preferably 5 to 100% by mass with respect to the mass of each component, Furthermore, 20 to 100% by mass is preferable, and further 50 to 100% by mass is preferable.

[0033] (C 1) The first succinic acid imide compound has a mass average molecular weight of 4,000 to

Has 7,000. The mass average molecular weight is preferably 5,000 to 7,000, more preferably 5,200-6,800. When the molecular weight of the first succinic acid imide compound is less than 4,000, the shudder characteristics deteriorate. In the present invention, the mass average molecular weight of the first succinic acid imide compound is as follows: solvent: THF (tetrahydrofuran), packed column: styrene • divinylbenzene copolymer, set temperature: 40 ° C, set flow rate 1. Om I minutes, measured in RI (differential refraction) detector, in terms of polystyrene

[0034] When a boronated succinimide compound is used as the first succinimide compound, the boron content in the component (C-1) is not limited, but the component (C-1) preferably from 0.1 to 3% by weight, based on the weight of the borated succinic acid imide compound is, further from 0.2 to 2.5 mass ^_0/0 are preferred, in a further 0.2 to 2 wt% In particular, 0.2 to 1.5% by mass is preferable. The nitrogen content in the (C-1) component is not limited, but it is preferably 0.3 to 10% by mass based on the mass of the boronated succinic acid imide compound that is the (C-1) component. Furthermore, 0.5 to 5% by mass is preferable, and 0.8 to 2.5% by mass is particularly preferable. [0035] The content of the first succinic acid compound in the lubricating oil composition is not limited, but is preferably 0.05 to 2 mass% with respect to the total mass of the lubricating oil composition. 0.08 to 1.8% by mass is more preferable, and 0.1 to 1.5% by mass is more preferable. If the content is less than the lower limit, sufficient cleanliness may not be ensured, and if the content exceeds the upper limit, sludge may be generated.

[0036] (C-2) The second succinic acid imide compound has a mass average molecular weight of more than 7,000 to 10,000. The mass average molecular weight is preferably 7,100-9,600, more preferably 7,500-9,200. If the molecular weight of the second succinic acid imide compound is more than 10,000, the low-temperature viscosity will deteriorate.

In the present invention, the mass average molecular weight of the second succinic acid imide compound is as follows: solvent: THF (tetrahydrofuran), packed column: styrene-divinylbenzene copolymer, set temperature: 40 ° C, set flow rate 1. It is a polystyrene equivalent value measured with an RI (differential refraction) detector at Oml / min.

[0037] When a boronated succinic acid imide compound is used in the second succinic acid imide compound, the boron content in the component (C1-2) is not limited, but the component (C-2) The boron content is preferably 0.1 to 3% by mass, more preferably 0.2 to 2.5% by mass with respect to the mass of the boronated succinic acid imide compound. / ₀ is preferable, more preferably 0.2 to 2% by mass, and particularly preferably 0.2 to 1.5% by mass. The nitrogen content in the component (C1-2) is not limited, but is preferably 0.2-5% by mass relative to the mass of the boronated succinic acid imide compound as the component (C1-2). Is preferably 0.3 to 2.5% by mass, and more preferably 0.5 to 2% by mass.

[0038] The content of the second succinic acid imide compound in the lubricating oil composition include, but are not limited to, 0.1 is preferably 05-2 wt%, 0.1 08～. 8 mass ^_0/0 Gayo More preferred is 0.1 to 1.5% by mass. If it is less than the lower limit, sufficient cleanliness may not be ensured, and if it exceeds the upper limit, low temperature viscosity is generated. [0039] The lubricant composition of the present invention may further contain another ashless dispersant in combination with the component (C1-1) and the component (C1-2). Other ashless dispersants typically include succinic acid amide compounds.

[0040] (D) Phosphorus extreme pressure agent

The lubricating oil composition of the present invention essentially contains (D) a phosphorus extreme pressure agent. The phosphorus extreme pressure agent is an extreme pressure agent having phosphorus, and may be a conventionally known one. The content of the phosphorus-based extreme pressure agent in the lubricating oil composition is not limited, but is preferably from 0. 01 to 2.5% by mass based on the total mass of the lubricating oil composition, and from 0. 02 to 1 5% by mass is more preferable, and 0.02 to 1.0% by mass is more preferable. The phosphorus-based extreme pressure agent in the present invention may have sulfur. Phosphorus-sulfur-based extreme pressure agents such as citrate phosphate are included in the phosphorus-based extreme pressure agent. Not included. However, in the present invention, the phosphorus-based extreme pressure agent does not include zinc dithiophosphate. Particularly preferably, the phosphorus extreme pressure agent in the present invention does not have a metal element.

[0041] The lubricating oil composition of the present invention may further contain a sulfur-based extreme pressure agent in addition to the phosphorus-based extreme pressure agent. The sulfur-based extreme pressure agent is an extreme pressure agent having sulfur and may be a conventionally known one. Further, as described above, the lubricating oil composition of the present invention does not contain zinc dithiophosphate. Therefore, the sulfur-based extreme pressure agent in the present invention does not include ditian zinc phosphate. Particularly preferably, the sulfur-based extreme pressure agent in the present invention does not have a metal element. The content of the sulfur type extreme pressure agent in the lubricating oil composition of the present invention is 0.1% by mass or less, preferably 0.08% by mass or less, more preferably 0.06% by mass in the lubricating oil composition. It is the amount that is less than or equal to mass%. If the lubricating oil composition contains a sulfur-based extreme pressure agent in the lubricating oil composition in an amount exceeding the above upper limit, the shudder characteristics will be poor.

[0042] As described above, the lubricating oil composition of the present invention does not contain zinc dithiophosphate. This is because the presence of zinc phosphate in the lubricating oil composition deteriorates the shudder characteristics of the lubricating oil composition.

[0043] The phosphorus extreme pressure agent is preferably a phosphate ester or an acidic phosphate ester. , Phosphites, acidic phosphites, and their amine salts, phosphoric acid, and phosphorous acid. These may be used alone or in combination of two or more. Particularly preferably, the phosphorus extreme pressure agent is at least one selected from phosphoric acid ester, acidic phosphoric acid ester, phosphite ester, acidic phosphite ester and their amine salts, and phosphoric acid. And a combination of at least one selected from phosphorous acid. In addition to these phosphorus-based extreme pressure agents, sulfur-based extreme pressure agents may be included, but the content thereof must satisfy the above-mentioned conditions.

[0044] Phosphoric acid ester and acidic phosphoric acid ester are (R'0) _a P (= 0) (OH) a

It is represented by a is 0 1 2 or 3; R ′ is independently a monovalent hydrocarbon group having a carbon number of 430. Here, the case where a = 1 or 2 is an acidic phosphate ester.

[0045] phosphites and acid phosphites ^{_{(R 2 0) b P (}} = 0) (0 H) 2 - represented by _b H. b is 0 1 or 2; R ² is independently a monovalent hydrocarbon group having a carbon number of 430.

[0046] The phosphoric acid ester and the acidic phosphoric acid ester are preferably a monoalkyl phosphate, a dialkyl phosphate, and a phosphoric acid trialkyl ester, but are not limited thereto.

[0047] The phosphite and acidic phosphite are preferably monoalkyl phosphite and dialkyl phosphite, but are not limited thereto.

[0048] Further, as the phosphorus-based extreme pressure agent, a compound in which a part of oxygen atoms of the above-described phosphoric acid ester, phosphorous acid ester, acidic phosphoric acid ester or acidic phosphorous acid ester is substituted with a sulfur atom, for example, Also included are thiophosphate, citrus phosphite, citrate phosphate, and citrate phosphite.

[0049] In more detail, mono-octyl phosphate, di-octyl phosphate, tri-octyl phosphate, mono-octyl phosphite, di-octyl phosphite, di-octyl phosphate mono-octyl, di-octyl phosphate Di-year-old octyl, tri-year-old trioctyl phosphate, di-year-old monophosphite Dioctyl phosphate, didodecyl phosphate, monododecyl phosphate, tridodecyl phosphate, monododecyl phosphite, didodecyl phosphite, acidic butyl ester phosphate, acidic hexyl phosphate ester, acidic Examples include phosphoric acid octyl ester, acidic phosphoric acid dodecyl ester, acidic phosphite butyl ester, acidic phosphite hexyl ester, acidic phosphite dioctyl ester, acidic phosphite dodecyl ester, etc. Not limited

[0050] Furthermore, alkylamine salts and alkenylamine salts of the above compounds which are partial esters can also be suitably used. That is, an amine salt of an acidic phosphate ester and an amine salt of an acidic phosphite ester can be used, but are not limited thereto.

[0051] More specifically, monoamine octyl phosphate amin salt, dioctyl phosphate amine salt, trioctyl phosphate amine salt, dioctyl phosphite amine salt, trioctyl phosphite amin salt, Amide salt of dioctyl phosphate, Amide salt of lyoctyl thiophosphate, Amide salt of didecyl phosphate, Amide salt of didecyl phosphate, Amine salt of didecyl phosphite, Amide of didodecyl phosphate Salt, tridodecyl phosphate ammine salt, dododecyl phosphite ammine salt, tridodecyl phosphite ammine salt, amido salt of tridecyl phosphate, amido salt of trihexadecyl phosphate, Amine salt of trihexadodecyl phosphate, Amine salt of acidic phosphite butyl ester, Amine salt of acidic phosphate hexyl ester, Acidic phosphate Amine salt of ester, amine salt of acidic phosphoric acid dodecyl ester, amine salt of acidic phosphite butyl ester, amine salt of acidic phosphorous acid hexyl ester, amine salt of acidic phosphorous acid octyl ester, acidic phosphorous acid Examples include amine salts of dodecyl esters.

[0052] In addition, phosphoric acid and phosphorous acid are preferably used as phosphorus-based extreme pressure agents other than those described above. In addition, but not limited to, at least one selected from acidic phosphate ester, acidic phosphite ester, phosphate ester, phosphite ester, and amine salts thereof, and phosphoric acid and phosphite. At least selected from phosphoric acid In combination with at least one kind is preferred. The ratio of phosphoric acid and phosphorous acid when used in combination is not particularly limited, but phosphoric acid and phosphorous acid are 0.02 to 0.5 mass% with respect to the total mass of the phosphorous extreme pressure agent. Is preferred.

[0053] Further, in particular, it is selected from an acidic phosphate, phosphoric acid and phosphorous acid.

A combination with one or more is preferred. In particular, the acidic phosphate ester is preferably at least one selected from acidic phosphoric acid butyl ester, acidic phosphoric acid hexyl ester, acidic phosphoric acid-containing ethyl ester, and acidic phosphoric acid dodecyl ester.

[0054] Examples of the sulfur-based extreme pressure agent include sulfurized olefins, sulfurized fats and oils, sulfurized esters, and polysulfide.

[0055] Sulfurated refin is a compound obtained by sulphurizing refins. The sulfurized olefin is obtained, for example, by sulfurizing olefins such as polyisobutylenes and terpenes with sulfur or other sulfiding agents.

[0056] Sulfurized fat and oil is a reaction product of fat and sulfur. For example, it can be obtained by sulfurizing animal and vegetable oils such as lard, beef tallow, whale oil, palm oil, coconut oil and rapeseed oil. The product obtained by the reaction is not a single substance species but may be a mixture of various substances. Therefore, the chemical structure is not always clear.

[0057] In addition to the above-mentioned sulfurized fats and oils, sulfurized esters are obtained by converting ester compounds obtained by the reaction of various organic acids (saturated fatty acids, unsaturated fatty acids, dicarboxylic acids, aromatic carboxylic acids, etc.) with various alcohols to sulfur and other sulfurized compounds. And those obtained by sulfurization with an agent. Like sulfurized fats, the chemical structure is not always clear.

[0058] The lubricating oil composition of the present invention preferably further comprises (E) a metal detergent and / or (F) an ether sulfolane compound in addition to the components (A) to (D).

[0059] (E) Metal detergent

Examples of metal detergents include detergents having an alkali metal or an alkaline earth metal. For example, sulfonates containing alkali metals or alkaline earth metals, salicylates containing alkali metals or alkaline earth metals, Examples include, but are not limited to, phenates containing Lucari metal or alkaline earth metal. Examples of the alkali metal or alkaline earth metal include, but are not limited to, magnesium, barium, sodium, and calcium.

[0060] The sulfonate containing alkali metal or alkaline earth metal is not limited, but calcium sulfonate and magnesium sulfonate are preferably used.

[0061] The salicylate containing an alkali metal or an alkaline earth metal is not limited, but calcium salicylate and magnesium salicylate are preferably used.

[0062] The phenate containing an alkali metal or an alkaline earth metal is not limited, but calcium phenate and magnesium phenate are preferably used.

[0063] The amount of alkali metal or alkaline earth metal contained in the metal detergent include, but are not limited to, 0.1 is preferably 1 to 20 mass%, 0.5 to 1 5 weight ^_0/0 Gayori preferably 1.0 to 15% by mass is more preferable.

[0064] The metal detergent is not limited, but preferably has a total base number of 10 to 50 Omg KOH / g, more preferably 50 to 40 Omg KOH / g, and 150 to 400 mg KOH / g is more preferred. In particular, when it is 200 to 400 mg KOHZg, more preferably 300 to 40 Omg KOH / g, most preferably, when it is 310 to 400 mg KOH / g, the cleansing effect is also obtained. Most preferable because it is high and sludge generation can be suppressed.

[0065] The metal detergent may be contained in the lubricating oil composition in an arbitrary ratio. For example, it is 0 to 5% by mass, more preferably 0.1 to 2% by mass, and still more preferably 0.2 to 1% by mass.

[0066] The metal detergents may be used alone or in combination of two or more. Even if they are used together, there is no limitation on the type. For example, The lysylate compound and the phenate compound may be used, but a combination of a sulfadate compound and a salicylate compound, a sulfonate compound and a phenoate compound, or a combination of a sulcillate compound and a phenoate compound may be used.

[0067] (F) Ether sulfolane compound

By containing the ether sulfolane compound, the lubricating oil composition of the present invention can further ensure appropriate seal rubber swelling. The ether sulfolane compound is the following compound.

[Chemical 5]

In the above formula, R is an alkyl group having〗 -20 carbon atoms, preferably an alkyl group having 8-16 carbon atoms.

[0068] The blending amount of the ether sulfolane compound is preferably 0 to 5% by mass, more preferably 0.2 to 2% by mass, and more preferably 0.2 to 1% by mass in the lubricating oil composition.

[0069] The lubricating oil composition of the present invention may further contain other additives other than the above (B) to (F). For example, oily agents, antiwear agents, extreme pressure agents other than phosphorus and sulfur extreme pressure agents, rust inhibitors, friction modifiers, antioxidants, corrosion inhibitors, metal deactivators, pour point depressants, Antifoaming agents, coloring agents, and package additives for automatic transmission oils. Various lubricating oil package additives containing at least one of these can also be added.

[0070] The kinematic viscosity at 100 ° C of the lubricating oil composition of the present invention is not limited, but is preferably 3 to 10 mm ² / s, and 3 to 8 mm ² / s. More preferably, it is more preferably 4 to 7.5 mm ² / s, and 4 to 6 m. More preferably, m ² / s. If the kinematic viscosity at 100 ° C of the lubricating oil composition is less than the above lower limit value, the friction coefficient may not be sufficiently secured. Further, if it exceeds the above upper limit value, the shudder characteristic may be deteriorated.

[0071] The viscosity index of the lubricating oil composition of the present invention is not limited, but is preferably 150 or more, and more preferably 60 or more. If the viscosity index of the lubricating oil composition is less than the above lower limit, it may not be possible to secure sufficient low shear characteristics. The upper limit is not limited, but is preferably 250.

[0072] The lubricating oil composition of the present invention has an effect that it has a sufficiently large coefficient of friction between metals and can secure a shudder characteristic despite its low viscosity. Further, as described above, shear stability can be ensured by further specifying the composition of the base oil and the viscosity index improver according to the present invention. Furthermore, by containing an ether sulfolane compound, it is possible to ensure an appropriate seal rubber swelling property. Furthermore, the use of a metal detergent having a total base number of 200 to 40 Omg KO H / g is preferable because it can suppress the generation of sludge while ensuring cleanliness. The lubricating oil composition of the present invention can be suitably used for a continuously variable transmission.

Example

[0073] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0074] Each component used in Examples and Comparative Examples is as follows. Each component shown below was mixed in the composition shown in Table 1 or Table 2 to prepare a lubricating oil composition. In the following, KV 100 means kinematic viscosity at 100 ° C, VI means viscosity index, and PMA means polymethacrylate.

(A) Lubricating base oil

'Mineral oil 1: highly hydrorefined paraffinic base oil (KV 1 00 = 3.1 mm ² / s, VI = 1 1 2)

-Mineral oil 2: Highly hydrorefined paraffinic base oil (KV 1 00 = 4.2 mmVs VI = 1 22)

Mineral oil 3: Highly hydrorefined paraffinic base oil (KV 1 00 = 4.2 mm 2 / s

(V I = 1 34)

Mineral oil 4: Hydrorefined paraffinic base oil (KV 1 00 = 2.2 mm ² / s, V = 1 9)

Mineral oil 5: Hydrorefined paraffinic base oil (K V 100 = 2.5 mm ss V = 99)

Synthetic base oil 1: Poly α-year-old refin (KV 1 00 = 10 mm ² s, VI =

37)

• Synthetic base oil 2: Poly α-year-old refin (KV 1 00 = 40mm ² / s, VI = 1 47)

• Synthetic base oil 3: Ethylene mono-alpha olefin copolymer (KV 1 00 = 10 mm ² / s, VI = 1 50)

• synthetic base oil 4: Ethylene one α- old olefin copolymer ^{(KV 1 00 = 40mm 2 /} s, VI = 1 55)

[0075] (B) Viscosity index improver

• PMA viscosity index improver 1 (Mw = 30,000)

[0076] (C) Borated succinic acid imide compound

(C- 1)

'Boronated succinic acid imide compound 1 (Mw = 5, 600, B: 0.34 wt, N = 1.58 wt%, in the above formula (2), R ¹ is a polyisobutenyl group, n = 4 to 2 blend)

'Boronated succinic acid imide compound 3 (Mw = 4,600, B: 1. 8 wt%, N = 2.35 wt%, in the above formula (2), R ¹ is a polyisobutenyl group, n = 4 to 2 A mixture of

(C-2)

'Boronated succinic acid imide compound 2 (Mw = 8, 500, B: 0.23 wt%, N = 0.88wt%, in formula (2) above, R' is polyisobutenyl Group, _n = 4 to 1 2)

[0077] (D) Extreme pressure agent

(D— 1) Phosphoric acid

(D-2) Phosphorous acid

(D-3) Acidic butyl phosphate

(D-4) Amine salt of acidic butyl phosphate

(D-5) Acid hexyl ester

(D—6) Acid phosphite butyl ester

(D-7) Olefin sulfide

(D-8) Dialkyl divalent zinc phosphate (primary alkyl group with 6 carbon atoms) [0078] (E) Metal detergent

• C a sulphone (total base number 35 Om 9 KOH / g)

[0079] (F) Ether sulfolane compound

• LU BR I ZOL 730 (compound with R ¹ = C, ₀ H ₂ in the following formula)

[Chemical 6]

[0080] (G) Other additives

Antiwear agent, friction modifier, antioxidant, antifoam agent, metal deactivator, and colorant

[0081]

Table 2

3]

TO

Various properties of each lubricating oil composition were measured according to the following method. The results are shown in Table 46. (1) Kinematic viscosity at 100 ° C (KV 100) Test method: AST Measured according to M D445.

(2) Viscosity index test method: Measured according to ASTM D 2270.

(3) Shear stability test method: According to JASO M347-2014, the viscosity at 100 ° C after 10 hours was measured, and the rate of change from the viscosity before the start of the test was determined.

(4) Anti-shudder life test method: 40 ° C, 60 ° C, 80 ° C, 1 2 (evaluated at TC d xZd v (1.0 0-2

. Mean in OmZs) either has asked for time below one 2 x 1 0_ ^3.

(5) Friction coefficient (compared with commercial products): Made by Optimol, S RV friction and wear tester, SU J ball (diameter 1 Omm), SU J disk (diameter 24mmx height 6.9) mm _s lapping), load: 1 O ON, temperature: 100 ° C, frequency: 5 OH z, amplitude: 0.5 mm, and the average value of the coefficient of friction after 30 minutes Asked. The friction coefficient of the commercial oil (Comparative Example 5) is 1

The ratio was determined as 0.

(6) Rubber swelling test method: ASTM D47 1 C type dumbbell-shaped ACM rubber (NOK T945) was immersed in sample oil at 150 ° C and volume change after 70 hours The rate was determined.

[0083] In Comparative Example 5, a commercially available lubricating oil composition for a transmission was evaluated.

[0084]

Table 4

Example 1 Example 2 Example 3 Example 4 Actual base oil V100 4.0 4 0 4.0 3.7

KV100 5.5 5.5 5.5 5.2

[] 0085

VI 163 168 170 168 Shear stability 4 4 4 4 Composition Shader 450 450 450 450 Friction coefficient

1.00 1.00 1.00 1.00

(Ratio ¾ Relative ratio with Example 5)

Swellability 5 5 5 5

Table 5

6) Table 6

[0087] As shown in Examples 1 to 15 described in Table 4 and Table 5, the lubricating oil composition of the present invention contains two types of succinic acid imides, and contains a phosphorus-based extreme pressure agent. Therefore, despite the low kinematic viscosity at 100 ° C., the anti-shudder life can be extended without lowering the coefficient of friction between metals. As shown in Comparative Example 1, if the (C-2) component is not included, the shudder characteristic is deteriorated. In addition, as shown in Comparative Example 4, when the dilute zinc phosphate is included, the shudder characteristic is deteriorated. Furthermore, if the sulfur-based extreme pressure agent is contained in excess of the upper limit of the present invention, the shudder characteristic is deteriorated.

Further, as can be seen from the comparison between Example 1 and Example 8, (A) the composition of the component is specified, and (F) further containing ether sulfolane further improves the seal rubber swelling property in addition to the above effects. can do.

Industrial applicability

[0088] The lubricating oil composition of the present invention can be particularly suitably used for automobile transmissions, particularly for continuously variable transmissions.

Claims

The scope of the claims

(A) Lubricating base oil,

(C) (C 1) succinic acid imide compound or boronated succinic acid imide compound having a weight average molecular weight of 4,000 to 7,000,

(D) A lubricating oil composition comprising a phosphorous extreme pressure agent, wherein the lubricating oil composition does not contain zinc dithiophosphate and may optionally contain a sulfur extreme pressure agent. However, the content of the sulfur-based extreme pressure agent is 0.1% by mass or less in the lubricating oil composition.

As a part or all of the component (A), a poly α-age refin or α-age olefin copolymer having a kinematic viscosity of 6 to 80 mm ² / s at 100 ° C is added to the entire lubricating oil composition. 5-30% by mass with respect to the mass, and

(I) The lubricating oil composition according to claim 1, further comprising polymethacrylate having a weight average molecular weight of 15,000 to 40,000.

The lubricating oil composition according to claim 1 or 2, wherein a part or all of the component (C-1) and the component (C1-2) is a boronated succinic acid compound. In each of the (C 1 1) component or the (C-2) component, the boron content is 0.1 to 3% by mass relative to the mass of the fluorinated succinic acid imide compound. The lubricating oil composition according to any one of 3

[Claim 5] The mass ratio of the (C 1 1) component to the (C 1 2) component is (C 1 2) /

The lubricating oil composition according to any one of claims 1 to 4, wherein (C 1 1) = 1 to 10.

[6] The lubricating oil composition according to any one of claims 1 to 5, wherein the succinic acid imide compound is represented by the following formula (1) or (2). [Chemical 1]

[Chemical 2]

In the above formula, R ¹ is independently an alkyl or alkenyl group having 40 to 40 carbon atoms, m is an integer of ˜20, and n is an integer of 0 to 20.

1 0 0 C has a kinematic viscosity 3~ 1 0 mm ² / s at, the lubricating oil composition of any one of claims 1-6.

The lubricating oil composition according to any one of claims 1 to 7, which has a viscosity index of 1550 or more.

(D) The phosphorus extreme pressure agent is at least one selected from acidic phosphoric acid ester, acidic phosphorous acid ester, phosphoric acid ester, phosphorous acid ester, and amine salts thereof, phosphoric acid, and phosphorous acid The lubricating oil composition according to any one of claims 1 to 8, wherein the lubricating oil composition is at least one species.

(D) the phosphorus extreme pressure agent is at least one selected from acidic phosphoric acid ester, acidic phosphorous acid ester, phosphoric acid ester, phosphorous acid ester, and amine salts thereof, and phosphoric acid and 10. The lubricating oil composition according to claim 9, which is a combination with at least one selected from phosphorous acid. [Claim 11] The lubricating oil composition according to any one of claims 1 to 10, further comprising (E) a metal detergent.

[Claim 12] The composition further comprises (F) an ether sulfolane compound.

The lubricating oil composition according to any one of 1 above.

[Claim 13] The lubricating oil composition according to any one of claims 1 to 12, which is used for a continuously variable transmission.