Lubricating oil base oil and lubricating oil composition

Abstract

Improvements in cooling performance, fuel efficiency, and other properties are desired for cooling lubricant compositions. [Solution]%C P The value is 60 or higher, and the kinematic viscosity at 40°C is 3 mm². 2 It is less than / s. A lubricating oil base oil is provided for use in the preparation of cooling lubricating oil compositions. Furthermore, a composition comprising this base oil is provided. A cooling lubricant composition is provided.

Description

[Technical Field]

[0001] The present invention relates to lubricating oil base oils and lubricating oil compositions, and for example, to cooling equipment for electric vehicles. This invention relates to a lubricating oil composition and a lubricating oil base oil used in its preparation. [Background technology]

[0002] In recent years, there has been a strong demand for reducing carbon dioxide emissions from the perspective of protecting the global environment. They are also focusing their efforts on developing fuel-saving technologies, and are producing vehicles with excellent fuel efficiency and environmental performance. The adoption of hybrid vehicles and electric vehicles is progressing. Equipped with a motor, generator, inverter, and battery, it runs using the power of an electric motor. ru.

[0003] Electric vehicle components such as electric motors and batteries can become less efficient or even break down when exposed to high temperatures. Cooling is necessary to prevent this. Electric motors in hybrid vehicles and electric vehicles and For cooling the generator, the existing automatic transmission fluid (hereinafter referred to as AT) is used. Lubricants such as F) and continuously variable transmission fluid (CVTF) are used. Furthermore, some hybrid and electric vehicles have gear reducers. Therefore, the lubricating oil compositions used in these applications need to possess not only lubrication but also cooling properties. For example, Patent Document 1 describes a kinetic energy recovery system (KERS) or hive A lubricating composition for cooling and / or insulating batteries or electric motors in a lidded vehicle It has been disclosed.

[0004] The cooling performance of the lubricating oil composition is low viscosity for cooling, which lowers the temperature of various devices. Furthermore, a high flash point is required to prevent various devices from igniting during cooling. Low viscosity and high flash point are generally in a trade-off relationship, making it difficult to achieve both characteristics simultaneously. Consideration is being given to find a way to achieve both. Furthermore, in recent years, there has been a high demand for fuel efficiency from the perspective of protecting the global environment and conserving energy. Yes, and lubricants are also required to have fuel-saving properties. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Special Publication No. 2013-522409 [Overview of the project]

[0006] Under these circumstances, improving cooling performance, fuel efficiency, and other properties of cooling lubricant compositions. That is desired. [Means for solving the problem]

[0007] The present invention includes the following embodiments. [1] %C P The value is 60 or higher, and the kinematic viscosity at 40°C is 3 mm³. 2 Less than / s, cold A lubricating oil base oil used in the preparation of lubricating oil compositions. [2] %C P The value is 60 or higher, and the kinematic viscosity at 40°C is 3 mm³. 2 Base oil less than / s (A) is contained, and the content of base oil (A) is 80% by mass or less of the total mass of the lubricating oil base oil. The lubricating oil base oil described in [1] above. [3] Further comprising a base oil (B) different from the base oil (A), The content of the base oil (B) is 1 to 20% by mass relative to the total mass of the lubricating oil base oil. The lubricating oil base oil described in [1] or [2]. [4] The base oil (A) is an isoparaffinic base oil as described in any of [1] to [3]. Lubricating oil base oil. [5] %C N A lubricating oil base oil according to any of [1] to [4], wherein the ratio is 21 or less. A cooling lubricant composition comprising a lubricating oil base oil as described in any of [6] [1] to [5]. [7] The content of the lubricating oil base oil is 30% by mass of the total mass of the cooling lubricating oil composition The cooling lubricant composition described above [6]. [8] The cooling lubricant composition has a kinematic viscosity of 3 mm at 40°C. 2 / s is less than [ Cooling lubricant composition as described in [6] or [7]. [9] The cooling lubricant composition has a flash point of 90°C or higher, any of [6] to "8" The cooling lubricant composition described above.

[10] The cooling lubricant composition has a pour point of -45°C or lower, one of [6] to "9" A cooling lubricant composition as described in any of the following.

[11] Cooling equipment for electric vehicles as described in any of [6] to

[10] Lubricating oil composition for use.

[12] The electric vehicle equipment includes a motor, a battery, an inverter, and an engine A cooling lubricant composition according to

[11] , which is at least one selected from n.

[13] A cooling device for cooling electric vehicle equipment, any of [6] to "12" An apparatus comprising the cooling lubricant composition described in (c).

[14] A method for cooling equipment for electric vehicles, as described in any of [6] to "12" By circulating the cooling lubricant composition within the electric vehicle equipment, the electric vehicle equipment A method that includes cooling the container. [Effects of the Invention]

[0008] To provide a lubricating oil composition for cooling, which is excellent in characteristics such as cooling performance and fuel cost savings, and a lubricating oil base oil used therefor.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described in detail. Note that the present invention is not limited to the following embodiments, and can be arbitrarily modified and implemented without departing from the gist thereof. The upper and lower limit values of the numerical ranges described in this specification can be arbitrarily combined. For example, when "A to B" and "C to D" are described, the ranges of "A to D" and "C to B" are also included in the scope of the present invention as numerical ranges. Further, the numerical range "lower limit value to upper limit value" described in this specification means that it is not less than the lower limit value and not more than the upper limit value.

[0010] One embodiment of the present invention relates to a lubricating oil base oil (hereinafter, also simply referred to as "base oil") in which %C P is 60 or more and the kinematic viscosity at 40 ° C is less than 3 mm 2 / s. The base oil is used for preparing a lubricating oil composition for cooling. Further, one embodiment of the present invention relates to a lubricating oil composition for cooling (hereinafter, also simply referred to as "lubricating oil composition") containing the lubricating oil base oil. The lubricating oil composition according to this embodiment further contains a lubricating oil base oil (component (A)) and, if necessary, other additives (component (B)). Hereinafter, the base oil according to this embodiment and each component contained in the lubricating oil composition will be described in order.

[0011] [Component (A): Base Oil] The base oil is such that %C P is 60 or more and the kinematic viscosity at 40 ° C is less than 3 mm 2 / s It is characterized by the following. Such base oils have low viscosity, yet possess a high flash point and high low-temperature fluidity. By incorporating this into lubricating oils, a lubricating oil composition with excellent cooling and fuel-saving properties can be created. It can be granted.

[0012] The base oil is %C P It is 60 or more. %C P If it is less than 60, the thermal conductivity is low and sufficient If sufficient cooling performance (cooling rate) cannot be obtained, or if the coefficient of friction (traction coefficient) increases, combustion may occur. Cost may worsen. Base oil %C P Preferably, from the viewpoint of cooling performance and fuel efficiency. It is 70 or more, more preferably 75 or more, and even more preferably 77 or more. Preferably 80 or higher. Base oil %C P There is no particular upper limit; the higher the better. For example, the %C of the base oil P It is 99 or less, or 95 or less, or 90 or less. In that embodiment, the base oil's %C P Preferably, it is 60 to 99, more The range is 70-99, more preferably 75-99, and even more preferably 77-95. And, more preferably, it is 80 to 90.

[0013] Base oil %C N The base oil's %C is preferably 21 or less. N If it is 21 or less, the thermal conductivity is high In addition to excellent cooling performance, it also has a reduced coefficient of friction (low traction coefficient) and is excellent for lubricating oils. It can provide improved fuel efficiency. Base oil %C N It is more preferably 20 or less, and even more preferably The base oil's %C is 18 or less, and particularly preferably 16 or less. N The lower limit is particularly restricted It may not be calculated, and may be 0, but for example, the base oil's %C Nis 1 or more, or 5 or more, It is 10 or more. In some embodiments, the base oil's %C N Preferably 1 to 21 It is more preferably 1 to 20, even more preferably 1 to 18, and even more preferably The value is between 5 and 17, and is particularly preferably between 10 and 16.

[0014] Base oil %C A It is preferable that it is 10 or less. A If the value is 10 or less, the thermal conductivity is high and cooling is effective. In addition to its superior performance, it also has a reduced coefficient of friction (low traction coefficient) and is excellent in terms of lubrication efficiency. It can improve fuel efficiency. A It is more preferably 7 or less, and even more preferably 5 or less. Yes, it is. The base oil's %C A The lower limit is not particularly restricted and may be 0, but for example, the base oil's %C A is 1 or more, or 2 or more, or 3 or more. In some embodiments, the base Oil %C A is preferably 1 to 10, more preferably 2 to 7, and even more preferably The value is between 3 and 5.

[0015] In this specification, %C P , %C N , and %C A This is according to ASTM D3238-95. The value was obtained by ring analysis (ndM method) in accordance with the standard. %C P , %C N , and %C A teeth These figures represent the proportion of carbon atoms belonging to the paraffinic, naphthenic, and aromatic components of the oil, respectively.

[0016] The kinematic viscosity of the base oil at 40°C (40°C kinematic viscosity) is 3 mm². 2 It is less than / s. Base oil 40 The kinematic viscosity at °C is 3 mm 2If the value is above / s, sufficient cooling performance cannot be obtained. Base oil kinematic viscosity at 40°C From the viewpoint of cooling performance, preferably 2.7 mm 2 It is less than or equal to / s, and more preferably 2. 5mm 2 The value is less than or equal to / s, and more preferably 2.4 mm 2 It is less than / s. Base oil at 40°C There is no particular lower limit to the kinematic viscosity; the lower the better, but for example, 1 mm 2 / s or more, or 1.5mm 2 / s or more, or 1.8mm 2 It is greater than / s. In some embodiments The kinematic viscosity of the base oil at 40°C is preferably 1 mm². 2 / s or more 3mm 2 Less than / s, Preferably 1.5 mm 2 / s or more 2.7mm 2 / s or less, and more preferably 1.8 mm 2 / s or more 2.5mm 2 / s or less, and particularly preferably 2mm 2 / s or more 2.4m m 2 It is less than or equal to / s.

[0017] The flash point of the base oil is preferably 90°C or higher, more preferably 100°C or higher, and further Preferably, the flash point is 105°C or higher. A flash point of 90°C or higher is preferable from the standpoint of handling safety. It is also less likely to cause odor problems. From the standpoint of handling safety, a higher flash point is preferable. The flash point of the base oil is, for example, 130°C or below, 125°C or below, or 120°C or below. This may be done. In some embodiments, the flash point of the base oil is preferably 90 to 130°C. The temperature is more preferably 100-125°C, and even more preferably 105-120°C. . In this specification, the flash point is determined in accordance with JIS K 2265-3:2007. Measurements were taken using the Key-Martens sealed method (PM method).

[0018] The base oil is preferably one with a pour point of -45°C or lower, and more preferably one with a pour point of -47°C or lower. Preferably, the temperature is -50°C or lower. Such a base oil has low-temperature fluidity. Higher, potentially improving fuel efficiency at low temperatures. The pour point of the base oil is, for example, above -100°C, and -90°C. The pour point of the base oil may be above ℃ or -80℃. In some embodiments, the pour point of the base oil The temperature is preferably -100 to -45°C, more preferably -90 to -47°C, and More preferably, the temperature is -80 to -50°C. In this specification, the pour point is defined as in JIS K 2269:1987 (crude oil and petroleum products). This refers to values ​​measured in accordance with the pour point and cloud point test methods.

[0019] The base oil preferably has a thermal conductivity of 0.136 W / mK or higher, and preferably 0.138 W / mK or higher. Preferably, a value of 0.140 W / mK or higher is preferred. The higher the thermal conductivity, the faster the cooling rate. This can increase the cooling properties (fast cooling rate) of the lubricating oil. The thermal conductivity of the base oil is Preferably 0.200 W / mK or less, more preferably 0.180 W / mK or less, and 0.16 A value of 0 W / mK or less is even more preferable. In this specification, thermal conductivity is the value measured in accordance with ASTM D7896-19. It means.

[0020] The base oil is the above %C P And there are no particular limitations as long as it satisfies the kinematic viscosity at 40°C, and mineral oil It may be synthetic oil, or a combination of mineral oil and synthetic oil.

[0021] As for the mineral oil, any suitable mineral oil will be selected from those conventionally used as the base oil for lubricating oils. They can be selected and used. For example, the atmospheric residue obtained by atmospheric distillation of crude oil can be distilled under reduced pressure. The lubricating oil fraction obtained is subjected to solvent delamination, solvent extraction, hydrocracking, solvent dewaxing, and catalytic dewaxing. Examples include mineral oil refined by one or more treatments such as hydrogenation. It can be used alone, or in combination of two or more types.

[0022] There are no particular restrictions on synthetic oils, and any synthetic oils that have been conventionally used as base oils for lubricants may be used. Any of these can be appropriately selected and used. For example, synthetic oils are naphthenic compounds. Polyolefin compounds, isoparaffin compounds, aromatic compounds, ether compounds ester compounds, glycol compounds, gas-to-liquid oil (GTL), stone Examples include coal-to-liquid (CTL) oil. Synthetic oils may be used alone. You may use two or more types in combination.

[0023] Examples of naphthenic compounds include cyclohexane rings, bicycloheptane rings, and bicycloheptane rings. Compounds having a ring selected from the cutan ring are preferred. Examples of polyolefin compounds include α-olefin homopolymers (poly-α-olefins). ;PAO) and copolymers (e.g., ethylene-α-olefin copolymers) and their hydrogenation The items are favorably listed.

[0024] Ester compounds include methanol and ethanol, which are constituent alcohols (units). n-propanol, n-butanol, n-pentanol, n-hexanol, n- Heptanol, n-octanol, n-nonanol, n-decanol, n-undecano n-dodecanol, n-tridecanol, n-tetradecanol, oleyl alcohol ethylhexanol, butyl octanol, pentyl nonanol, hexyl decanol L, heptylundecanol, octyldodecanol, methylheptadecanol, ole Alcohol, benzyl alcohol, 2-phenethyl alcohol, 2-phenoxyethanol Ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether Tel, diethylene glycol monobenzyl ether, diethylene glycol monophenyl Monophenols such as ethers, phenols, cresols, xylenols, alkylphenols, etc. Ethylene glycol, diethylene glycol, triethylene glycol, polytetra Methylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pe Tananediol, 1,6-hexanediol, and polyethylene glycol (water at both ends) Acid group), triols such as trimethylolpropane and trimethylolethane, pentae Examples include tetraols such as lithritol. Alcohol (unit) alone or They can be used in combination.

[0025] The carboxylic acids (units) that make up the ester are n-butanoic acid, n-pentanoic acid, and n-hexa n-acid, n-heptanoic acid, n-octanoic acid, n-nonanoic acid, n-decanoic acid, n-undecanoic acid, n-dodecanoic acid Canic acid, n-tridecanoic acid, n-tetradecanoic acid, ethylhexanoic acid, butyloctanoic acid, pe Intylnonanoic acid, hexyldecanoic acid, heptylundecanoic acid, octyldodecanoic acid, meth Heptadecanoic acid, oleic acid, benzoic acid, toluic acid, phenylacetic acid, and phenoxyethanol Monocarboxylic acids such as cyacetic acid, adipic acid, azelaic acid, sebacic acid, 1,10-deca Examples of dicarboxylic acids include methylenedicarboxylic acid, phthalic acid, isophthalic acid, and terephthalic acid. Carboxylic acids (units) may be used alone or in combination.

[0026] As an example of an ester consisting of the alcohol and carboxylic acid mentioned above, polyethylene glycol Polyglycol benzoates such as dibenzoate and polypropylene glycol dibenzoate Acid esters, such as pentaerythritol n-octanoate tetraester and trimethylol pro Linear carboxylic acid hindered esters such as n-octanoic acid triesters of bread, azelaines Diesters such as di-n-octyl acid and ethylhexyl 1,10-decamethylenedicarboxylate , such as 16-methylheptadecanate dodecyl and 2-heptylundecanoate n-dodecyl Oleyl esters, such as oleyl oleate and 16-methylheptadecyl oleate Esters are preferred.

[0027] Aromatic compounds include alkylbenzenes, alkylnaphthalenes, and other alkyl aromatic compounds. Examples include compounds. Examples of ether compounds include polyphenyl ethers. Examples of glycol compounds include polyglycols such as polyoxyalkylene glycols. Oil is one example.

[0028] Coal to liquid (CTL) is produced by crushing coal, mixing it with a solvent, and heating it at high temperatures. CTL groups obtained by direct liquefaction methods (such as the Bergius process) involving direct reaction with hydrogen under high pressure. Oil and coal are first gasified (coal gasification), and the resulting gas is separated and purified and then reacted with the raw materials in a synthesis reaction. CTL base oil obtained by indirect liquefaction methods (such as the Fischer-Tropsch process), etc. There is. As for gas-to-liquid (GTL) oil, the residue wax in the GTL process is... GT is manufactured by hydrogenation and de-isomerization of (Gastri Liquid Wax) L-based oil is one example.

[0029] (Base oil (A)) The base oil is %C P The value is 60 or higher, and the kinematic viscosity at 40°C is 3 mm³. 2 The base is less than / s It is preferable that it contains oil (A). Base oil (A) %C P In addition to having high thermal conductivity and excellent cooling performance, it also has excellent fuel efficiency. Therefore, it is preferably 70 or more, more preferably 75 or more, and even more preferably The %C of the base oil (A) is 77 or higher, and is particularly preferably 80 or higher. P The upper limit is not particularly restricted. There are no limitations, and higher is better, but for example, the %C of the base oil (A) P is 99 or less, or 95 or less. It is below or 90. In some embodiments, the %C of the base oil (A) P is preferred More preferably 60-99, more preferably 70-99, and even more preferably 75-99 It is 9, more preferably 77-95, and especially preferably 80-90.

[0030] Base oil (A) %C N From the viewpoint of cooling performance and / or fuel efficiency, preferably 20 or less It is below, more preferably 18 or less, and even more preferably 16 or less. Base oil (A ) of %C N The lower limit is not particularly restricted and may be 0, but for example, the %C of the base oil (A) N is 1 or more, or 5 or more, or 10 or more. In some embodiments, the base %C of oil (A) N It is preferably 1 to 20, more preferably 5 to 18, and further Preferably, it is 10 to 16.

[0031] Base oil (A) %C A From the viewpoint of cooling and / or fuel efficiency, it is preferably 10 or less. The percentage of base oil (A) is 7 or less, more preferably 7 or less, and even more preferably 5 or less. C A The lower limit is not particularly restricted and may be 0, but for example, the %C of the base oil (A) A is, 1 The above, or 2 or more, or 3 or more. In some embodiments, base oil (A) %C A is preferably 1 to 10, more preferably 2 to 7, and even more preferably The range is 3 to 5.

[0032] The kinematic viscosity of the base oil (A) at 40°C (40°C kinematic viscosity) is preferably such that it has good cooling properties. 3mm 2 Less than / s, more preferably 2.7 mm 2 / s or less, and more preferably less than or equal to / s. 2.5mm 2 The value is less than or equal to / s, and is particularly preferably 2.4 mm 2 It is less than / s. Base oil (A The lower limit of the kinematic viscosity at 40°C is not particularly limited; a lower limit is better, for example, 1 mm 2 / s or more , or 1.5mm 2 / s or more, or 1.8mm 2 It is / s or more. In terms of form, the kinematic viscosity of the base oil (A) at 40°C is preferably 1 mm². 2 / s or more 3mm 2 / s Less than 1.5 mm, more preferably 1.5 mm 2 / s or more 2.7mm2 / s or less, and further Preferably 1.8 mm 2 / s or more 2.5mm 2 It is less than or equal to / s, and particularly preferably 2.2m m 2 / s or more 2.4mm 2 It is less than or equal to / s.

[0033] The flash point of the base oil (A) is preferably 90°C or higher, more preferably 100°C or higher. More preferably, the flash point is 105°C or higher. If the flash point is 90°C or higher, it poses safety concerns in terms of handling. Therefore, it is preferable, and odor problems are less likely to occur. From the standpoint of handling safety, a higher flash point is preferable. Which is preferable? The flash point of the base oil (A) is, for example, 130°C or lower, 125°C or lower, or 120°C. It may be below °C. In some embodiments, the flash point of the base oil (A) is preferably The temperature is 90-130°C, more preferably 100-125°C, and even more preferably 10 The temperature range is 5 to 120 degrees Celsius.

[0034] Base oil (A) may be used alone or in combination of two or more types. ) is the above %C P And there are no particular restrictions as long as it satisfies the kinematic viscosity at 40°C, and it is a mineral oil. It may be synthetic oil, or a combination of mineral oil and synthetic oil. The base oil (A) is a cooling oil. From a property standpoint, synthetic oils such as polyolefin compounds and isoparaffin compounds, isoparaffin Fin-based mineral oils are preferred. In a preferred embodiment, the base oil (A) is an isoparaffinic base oil. Fin-based oils have excellent cooling properties. Isoparaffin-based oils include gas-liquid oil (Gas to l Isoparaffin-based synthetic oil derived from iquid (GTL), coal liquefied oil obtained by indirect liquefaction method. (Coal to liquid; CTL) derived isoparaffinic synthetic oil, polymerization product of isobutene Conventional isoparaffinic synthetic oils, isoparaffinic mineral oils, etc., can be used.

[0035] The content of base oil (A) is preferably 80% by mass or more relative to the total mass of base oil. Preferably 82% by mass or more, even more preferably 85% by mass or more, and especially preferred Or it must be 90% by mass or more. There is no particular upper limit on the content of base oil (A), 100% by mass It can be %. In some embodiments, the content of base oil (A) is relative to the total mass of base oil. Preferably, it is 80-100% by mass, more preferably 82-100% by mass. More preferably, it is 85-100% by mass, and particularly preferably 90-100% by mass. In some embodiments, the amount is preferably 80-99% by mass of the total mass of the base oil. More preferably 82-97% by mass, and even more preferably 85-97% by mass. Particularly preferably, it is 90 to 96% by mass.

[0036] (Base oil (B)) The base oil may include base oil (A) and other base oils different from base oil (A). In that embodiment, the base oil further comprises a base oil (B) different from base oil (A). By including B), the kinematic viscosity of the lubricating oil base oil at 40°C (40°C kinematic viscosity) can be adjusted. It has advantages such as making it easier.

[0037] In some embodiments, the kinematic viscosity of the base oil (B) at 40°C (40°C kinematic viscosity) is From the perspective of balancing cooling performance and traction coefficient, 4-20mm 2 The range of / s is preferable. 4.5~15mm 2A range of / s is more preferable, 5-10mm 2 The range of / s is further preferable.

[0038] The flash point of the base oil (B) is preferably 90°C or higher, more preferably 120°C or higher. More preferably, the flash point is 150°C or higher. If the flash point is 90°C or higher, it poses safety concerns in terms of handling. Therefore, it is preferable, and odor problems are less likely to occur. From the standpoint of handling safety, a higher flash point is preferable. Which is preferable? The flash point of the base oil (B) is, for example, 200°C or lower, 180°C or lower, or 170°C. It may be below °C. In some embodiments, the flash point of the base oil (B) is preferably The temperature is 90-200°C, more preferably 120-180°C, and even more preferably 13 The temperature range is 0 to 170°C.

[0039] Base oil (B) may be used alone or in combination of two or more types. ) is not particularly limited, and can be mineral oil, synthetic oil, or a combination of mineral oil and synthetic oil. It's okay to have it. In some embodiments, the base oil (B) is mineral oil. In some embodiments, the base oil (B) is a synthetic oil (e.g., a polyolefin compound). That is the case. In some embodiments, base oil (A) is an isoparaffinic base oil, and base oil (B) It is either mineral oil or synthetic oil. In some embodiments, base oil (A) is an isoparaffinic base oil, and base oil (B) It is mineral oil. In some embodiments, base oil (A) is an isoparaffinic base oil, and base oil (B) This is a synthetic oil (for example, a polyolefin compound).

[0040] The content of base oil (B) is preferably 20% by mass or less relative to the total mass of base oil, Preferably 18% by mass or less, more preferably 15% by mass or less, and especially preferred The amount is 10% by mass or less. The lower limit of the base oil (B) content when base oil (B) is included is special Not limited to, for example, 1 mass or more, or 3% by mass or more, or 4% by mass or more Good. In some embodiments, the content of base oil (B) is preferred relative to the total mass of base oil. More preferably 1 to 20% by mass, more preferably 3 to 18% by mass, and even more preferably The amount is 3 to 15% by mass, and particularly preferably 4 to 10% by mass.

[0041] A lubricating oil composition can be made by blending base oils in the above form. The base oil is the main component of the lubricating oil composition. It is an ingredient, and the base oil content is usually preferably 30% by mass or more based on the total amount of the composition. Furthermore, it is more preferably 60% by mass or more, and even more preferably 65% ​​by mass or more. The layer preferably contains 70% by mass or more, and particularly preferably 80% by mass or more. For example, the base The oil content is preferably 30-100% by mass, more preferably 60% based on the total amount of the composition. ~100% by mass, more preferably 65~99.5% by mass, even more preferably 70~99% by mass This is a percentage by amount, and is particularly preferably 80-99% by mass.

[0042] [Ingredients (B): Other additives] The lubricating oil composition contains the above-mentioned lubricating oil base oil (component (A)) to the extent that it does not impair the effects of the present invention. In addition, anti-wear agents, antioxidants, viscosity index improvers, rust inhibitors, and metal inerts may be added as needed. Other additives such as conditioning agents, defoaming agents, detergent dispersants, and friction modifiers can be added. The total content of these other additives is not particularly limited, but according to lubricant composition standards, for example For example, approximately 0-40% by mass, or 0.5-35% by mass, or 1-30% by mass, It is 1-20% by mass.

[0043] (Anti-wear agent) There are no particular restrictions on the anti-wear agent, and it can be selected from among the anti-wear agents conventionally used in lubricating oils. Any of these can be selected and used as appropriate. For example, hybrid vehicles and electric vehicles When electric motors and gear reducers are used in combination in vehicles, electrical isolation should be minimized. To avoid impairing the properties, neutral phosphorus compounds, acidic phosphite esters or their amine salts, It is preferable to use sulfur-based compounds and the like. The amount of anti-wear agent is not particularly limited, but on a basis of the total composition, for example, 0.01 to 5 It is approximately a mass percent.

[0044] Examples of neutral phosphorus compounds include tricresyl phosphate and triphenyl phosphate. Trixylenyl phosphate, tricresylphenyl phosphate, tricresylthios Aromatic neutral phosphate esters such as phosphate, triphenylthiophosphate, and tributyl Phosphate, tri-2-ethylhexyl phosphate, tributoxy phosphate, tri Aliphatic neutral phosphate esters such as butylthiophosphate, triphenyl phosphite, Tricresyl phosphite, trisnonylphenyl phosphite, diphenyl mono-2-ether Tylhexyl phosphite, diphenyl monotridecyl phosphite, tolkresylthio Aromatic neutral phosphites such as phosphites and triphenylthiophosphites, Butyl phosphite, trioctyl phosphite, trisdecyl phosphite, trist Lidecyl phosphite, trioleyl phosphite, tolbutylthiophosphite, tri Examples include aliphatic neutral phosphites such as octylthiophosphite. These can be used individually or in combination of two or more types.

[0045] As an example of an acidic phosphite ester, di-2-ethylhexyl acid phosphate amine salt , dilauryl acid phosphate amine salt, dioleyl acid phosphate amine salt Aliphatic acid phosphate amine salts such as di-2-ethylhexyl hydrogen phosphatase Ito, dilauryl hydrogen phosphite, dioryl hydrogen phosphite, etc. Aliphatic acidous phosphate esters and their amine salts, diphenyl acid phosphate Aromatic acidic phosphate esters such as amine salts and dicresyl acid phosphate amine salts Min salt, diphenylhydrogen phosphite, dicresylhydrogen phosphite Which aromatic acidic phosphites and their amine salts, S-octylthioethyl phosphate dodecylthioethyl acid phosphate amine salts, etc. Sulfur-containing acidic phosphate amine salt, S-octylthioethylhydrogen phosphatide Sulfur-containing acidic phosphates such as S-dodecylthioethylhydrogen phosphite Examples include tel and their amine salts. These may be used individually or in pairs. You may use the above in combination.

[0046] Various sulfur compounds can be used, but specifically, thiadiazole Polysulfide compounds, dithiocarbamate compounds, sulfurized oil compounds Examples include sulfurized olefin compounds.

[0047] (Antioxidant) As antioxidants, known antioxidants that have been conventionally used as antioxidants in lubricating oils. Any of these can be appropriately selected and used. For example, amine-based antioxidants (Diphenylamines, naphthylamines), phenolic antioxidants, molybdenum acids Examples include antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, etc. Antioxidants are single-component antioxidants. They may be used individually or in combination of two or more. The content of antioxidants is not particularly limited. However, based on the total amount of the composition, it is, for example, about 0.05 to 7% by mass.

[0048] (Viscosity index improver) Examples of viscosity index improvers include polymethacrylate, dispersed polymethacrylate, Olefin copolymers (e.g., ethylene-propylene copolymers), dispersed olefins Styrene-based copolymers, styrene-based copolymers (e.g., styrene-diene copolymers, styrene-I) Examples include sorbene copolymers, etc. Viscosity index improvers may be used alone, or 2 More than one type may be used in combination. The amount of viscosity index improver is not particularly limited, For example, from the standpoint of formulation effectiveness, the amount should be approximately 0.5% by mass or more and 15% by mass or less based on the total amount of the composition. That is the case.

[0049] (Rust inhibitor) Examples of rust inhibitors include fatty acids, alkenyl succinate half-esters, and fatty acid secco. N, alkyl sulfonates, polyhydric alcohol fatty acid esters, fatty acid amides, oxidized paraffin Examples include phosphates and alkyl polyoxyethylene ethers. Rust inhibitors are used alone. It is also acceptable to use two or more types in combination. The preferred amount of rust inhibitor is not particularly limited. It is not possible to determine the exact amount, but it is approximately 0.01% by mass or more and 3% by mass or less based on the total amount of the composition.

[0050] (metal deactivator) Examples of metal deactivators include benzotriazole, triazole derivatives, and benzotriazole. Examples include triazole derivatives and thiadiazole derivatives. Metal deactivators can be used alone. It is also acceptable to use two or more types in combination. The content of the metal deactivator is not particularly controlled. While not limited to this, the amount is preferably 0.01 to 5% by mass based on the total amount of the composition.

[0051] (Antifoaming agent) Examples of defoaming agents include silicone compounds such as dimethylpolysiloxane, and polya Examples include acrylates. Antifoaming agents may be used alone or in combination of two or more types. It may be present. The amount of defoaming agent is not particularly limited, but on a basis of the total composition, it should be 0.0001 It is approximately between 5% and 5% by mass.

[0052] (cleaning dispersant) Examples of cleaning dispersants include succinimide compounds, boron-based imide compounds, and acid amides. Examples include system compounds. Cleaning dispersants may be used alone or in combination of two or more types. It may be used in this way. The content of the cleaning dispersant is not particularly limited, but preferably on a basis of the total composition. It is more accurately 0.01 to 20% by mass.

[0053] Examples of friction modifiers include known friction modifiers used in lubricating oils. Any suitable additive can be selected and used from among the available additives. For example, organic dithiolin Examples include salts, molybdenum-based friction modifiers, and ashless friction modifiers. Friction modifiers are simple It may be used alone, or two or more types may be used in combination. The amount of friction modifier is particularly important. While not limited, the amount is preferably 0.01 to 20% by mass based on the total amount of the composition.

[0054] [Properties of the Lubricant Composition] The lubricant composition preferably satisfies the properties of low viscosity and high flash point as cooling performance. . From the viewpoint of cooling performance, the kinematic viscosity at 40 °C (40 °C kinematic viscosity) of the lubricant composition is preferably less than 3 mm 2 / s, more preferably 2.8 mm 2 / s or less, and even more preferably 2.6 mm 2 / s or less, and particularly preferably 2.5 mm 2 / s or less. The lower limit of the 40 °C kinematic viscosity of the lubricant composition is not particularly limited, and the lower it is, the better. For example, 1 mm 2 / s or more, or 1.5 mm 2 / s or more, or 1.8 mm 2 / s or more. In some embodiments, the 40 °C kinematic viscosity of the lubricant composition is preferably 1 mm 2 / s or more and less than 3 mm 2 / s, more preferably 1.5 mm 2 / s or more and 2.8 mm 2 / s or less, even more preferably 1.8 mm 2 / s or more and 2.6 mm 2 / s or less, and particularly preferably 2 .2 mm 2 / s or more and 2.5 mm 2 / s or less.

[0055] The flash point of the lubricant composition is preferably 90 °C or higher, more preferably 92 °C or higher, even more preferably 95 °C or higher, and particularly preferably 100 °C or higher. When the flash point is 90 °C or higher , it is preferable from the viewpoint of handling safety, and the problem of odor is also less likely to occur. From the aspect of handling safety , the higher the flash point, the better. The flash point of the lubricant composition is, for example, 130 °C or lower The temperature may be 125°C or lower, or 120°C or lower. In some embodiments, lubrication The flash point of the oil composition is preferably 90 to 130°C, and more preferably 92 to 125°C. The temperature is more preferably 95-120°C, and particularly preferably 100-115°C. ru.

[0056] From the viewpoint of low-temperature fluidity, the lubricating oil composition is preferably one with a pour point of -45°C or lower. A temperature of -47°C or lower is more preferable, and a temperature of -50°C or lower is even more preferable. The higher the thermal fluidity, the better the starting performance and the greater the potential for improved fuel efficiency. The lower limit of the pour point of the lubricating oil composition is There are no particular restrictions, and lower is better, but for example, the pour point of a lubricating oil composition should be -100°C or higher. Alternatively, the temperature is above -90°C or above -80°C. In some embodiments, lubrication is used. The pour point of the oil composition is preferably -100 to -45°C, more preferably -90 to - The temperature is 47°C, and more preferably -80 to -50°C.

[0057] The lubricating oil composition has a thermal conductivity of 0.136 W / mK, in terms of cooling performance (fast cooling rate). The above is preferable, 0.138 W / mK or higher is more preferable, and 0.140 W / mK or higher is preferable. Furthermore, it is preferable. There is no particular upper limit to the thermal conductivity of the lubricating oil composition; the higher the better, however Furthermore, the thermal conductivity of the lubricating oil composition is 0.200 W / mK or less, or 0.180 W / mK. The following is true, or 0.160 W / mK or less. In some embodiments, the lubricating oil composition The thermal conductivity of the material is preferably 0.136 to 0.200 W / mK, and 0.138 to 0.180 W / mK is more preferred, and 0.140 to 0.160 W / mK is even more preferred.

[0058] The lubricating oil composition preferably has a traction coefficient of 0.028 or less, and preferably 0.026 or less. More preferably, a value of 0.024 or less is even more preferable. The lower the traction coefficient, the lower the friction coefficient. The number is low, leading to fuel efficiency. There is no particular lower limit to the traction coefficient of the lubricating oil composition. However, it is 0.010 or higher, or 0.015 or higher, or 0.018 or higher. In this embodiment, the traction coefficient of the lubricating oil composition is preferably 0.010 to 0.028. More preferably, 0.015 to 0.026 is preferable, and even more preferably 0.018 to 0.024. It's nice. In this specification, the traction coefficient is measured by the method described in the examples below. .

[0059] [Uses of lubricating oil compositions] The lubricating oil composition of the present invention described above provides lubricity and excellent cooling performance (for example) , low viscosity and high flash point; furthermore, in addition to low viscosity and flash point, high low-temperature fluidity (low flow) It has a moving point and / or high thermal conductivity. Therefore, as a cooling lubricant composition, It can be suitably used for cooling various types of equipment, particularly electric vehicles and hybrid vehicles. It is preferably used for cooling vehicle equipment, such as motors, batteries, and inverters. , and as a cooling oil for at least one electric vehicle component selected from the engine This is preferable.

[0060] [Cooling device] Lubricating oil compositions provide lubrication and cooling effects to various types of equipment. For example, The lubricating oil composition provides lubrication to various devices, such as those used in electric vehicles, by circulating it through the devices. At the same time, the equipment is cooled. One embodiment is a cooling device for cooling equipment for electric vehicles. The present invention provides an apparatus equipped with the lubricating oil composition described above. At least one selected from the motor, battery, inverter, and engine It is used in cooling devices for cooling equipment in electric vehicles. For example, a lubricating oil composition is used in hydraulic systems. Used in devices, stationary transmissions, automotive transmissions, and cooling systems for motors or batteries. It is possible.

[0061] [Method for producing a lubricating oil composition] The method for producing the lubricating oil composition is not particularly limited. Method for producing a lubricating oil composition according to one embodiment This involves mixing component (A) (lubricating oil base) and, if necessary, component (B) (other additives). This includes the fact that ingredient (A) and ingredient (B), if necessary, may be formulated in any way. Generally, the order and method of mixing are not limited. [Examples]

[0062] The present invention will be described in detail below with reference to examples, but the technical scope of the present invention is not limited thereto. It is not something that should be done.

[0063] The raw materials used in the examples and comparative examples, as well as the lubricating oil base oils of each example and comparative example. The physical properties of the lubricating oil composition were measured using the method described below. (1)Kinematic viscosity In accordance with JIS K2283:2000, a glass capillary viscometer was used at 40°C. The kinematic viscosity (kinematic viscosity at 40°C) was measured. (2) Flash point The flash points of the lubricating oil base oil and lubricating oil composition were measured using two methods. The flash point (PM) is determined in accordance with JIS K 2265-3:2007, and the penskin tarts are used. Measurements were taken using the sealed method (PM method). (3) Thermal conductivity The thermal conductivity of lubricating oil base oil and lubricating oil composition was determined using a thermal conductivity meter manufactured by C-Therm. Next, the thermal conductivity at 40°C was measured. (4) Pour point The pour point is defined in JIS K 2269:1987 (Pour point and cloud point of crude oil and petroleum products). Measurements were taken in accordance with the test method. (5)%C P , %C N , and %C A %C P , %C N , and %C A This is in accordance with ASTM D3238-95, and ring analysis (n Measured using the -dM method.

[0064] Furthermore, cooling performance tests and traction coefficient measurements were performed on the lubricating oil compositions of each example and comparative example. The determination was made using the following method. (Cooling test: Surface temperature after 12 seconds) In accordance with the "Cooling Performance Test Method: Method A" specified in JIS K2242, the temperature was set to 200°C. A heated silver rod was placed in 250 mL of sample oil heated to 30°C, and the temperature of the silver rod surface after 12 seconds was measured. This is the measured value.

[0065] (Traction coefficient measurement) The traction coefficient (MTM) is measured using a traction coefficient measuring instrument (product name: MTM2 (Min Using i Traction Machine 2 (manufactured by PCS Instruments) The values ​​were measured under the following measurement conditions. (Measurement conditions) First, the oil tank is heated with a heater to raise the oil temperature to 40°C, and the load is 20N. The traction coefficient was measured at an average rolling speed of 2 m / s and a slip ratio (SRR) of 50%. .

[0066] [Examples 1-6, Comparative Examples 1-4] The base oil components shown in Table 1 are mixed to prepare a lubricating oil base oil, and then mixed with other additives. By doing so, the lubricating oil compositions of the examples and comparative examples were prepared. The properties were obtained by the above method. Evaluation, cooling performance tests, and traction coefficient measurements were performed. The results are shown in Table 1.

[0067] [Table 1]

[0068] The components shown in Table 1 are as follows: 1.Lubricant base oil • Base oil (A) Base oil-1: Isoparaffinic base oil, kinematic viscosity 2.2 mm at 40°C. 2 / s, flash point (PM) 11 0℃, %C P 81% Base oil-2: Isoparaffin-based base oil, kinematic viscosity 2.2 mm at 40°C. 2 / s, flash point (PM) 10 6℃, %C P 81% Base oil-3: Isoparaffin-based base oil, kinematic viscosity 2.2 mm at 40°C. 2 / s, flash point (PM) 10 0℃, %C P 76% • Base oil (B) Mineral oil-1: Paraffinic mineral oil, kinematic viscosity 2.4 mm at 40°C. 2 / s, flash point (PM) 106℃ , %C P 44% Mineral oil-2: Aromatic mineral oil, kinematic viscosity at 40°C is 2.2 mm. 2 / s, flash point (PM) 100℃ , %C P 36% Mineral oil-3: Paraffinic mineral oil, kinematic viscosity at 40°C: 7.1 mm² 2 / s, flash point (PM) 165℃ , %C P 73% Synthetic oil-1:PAO (poly-α-olefin), kinematic viscosity at 40°C: 5.1 mm²2 / s, flash point (PM) 161℃ 2. Other additives A mixture of metal deactivators, anti-wear agents, friction modifiers, antioxidants, cleaning dispersants, and defoamers.

[0069] As shown in Table 1, %C P and lubrications of Examples 1-6 in which the kinematic viscosity at 40°C is within a specific range. Oil base oils have a low kinematic viscosity at 40°C, high thermal conductivity, a low pour point (high low-temperature fluidity), and high It was superior in characteristics such as flash point of 1 or higher. Lubricants formulated with the lubricating oil base oils of Examples 1 to 6 The oil composition has a low kinematic viscosity at 40°C, high thermal conductivity, a low pour point (high low-temperature fluidity), and It was superior in one or more properties, including a high flash point. In addition, the lubricating oil base oils of Examples 1 to 6 were used. The combined lubricant composition exhibited a low traction coefficient and a low table after 12 seconds in the cooling test. It exhibits surface temperature (high cooling rate, decrease in the temperature of the object being cooled), and offers excellent fuel efficiency and cooling performance. This was confirmed. Also, %C P Example 3, which had a higher and lower kinematic viscosity at 40°C, performed better in the cooling test. The surface temperature was remarkably low after several seconds, confirming that the cooling performance was exceptionally good. %C P And by using a lubricating oil base oil whose kinematic viscosity at 40°C is within a specific range, a low 40°C kinematic viscosity, high thermal conductivity, low pour point (high low-temperature fluidity), high flash point, fuel efficiency (for example) (Low traction coefficient), high cooling rate, and one or more characteristics of the temperature drop of the object being cooled. It is found that excellent results can be obtained, resulting in a well-balanced lubricating oil composition. Therefore, in some embodiments of the present invention, %C P and the kinematic viscosity at 40°C is within a specific range. By using a certain lubricating oil base, fuel efficiency (e.g., a low traction coefficient) and cooling can be improved. Excellent properties (for example, low surface temperature after 12 seconds (high cooling rate, decrease in the temperature of the object being cooled)) A lubricating oil composition is provided. In a preferred embodiment of the present invention, C P and 40°C kinematic viscosity By using a lubricating oil base oil with a specific degree range, fuel efficiency can be improved (for example, low traction). (Coefficient) and cooling performance (e.g., low surface temperature after 12 seconds (high cooling rate, temperature of the object being cooled) In addition to the decrease in kinematic viscosity at 40°C, it has low kinematic viscosity, high thermal conductivity, and a low pour point (high low-temperature fluidity). A lubricating oil composition is provided that is excellent in one or more properties, including a high flash point.

[0070] In contrast to this, %C P The lubricating oil base oils of Comparative Examples 1 and 2, which have a value less than 60, have low thermal conductivity. Furthermore, the lubricating oil compositions containing the lubricating oil base oils of Comparative Examples 1 and 2 have a high traction coefficient and are energy-efficient. It was confirmed that it has poor fuel efficiency. kinematic viscosity at 40°C is 3 mm 2 The lubricating oil base oils of Comparative Examples 3 and 4, which were ≥ / s, showed surface after 12 seconds. The temperature (cooling performance test) was too high, and sufficient cooling performance could not be obtained.

[0071] The scope of the present invention is not limited to the above description, and the present invention also applies to things other than those exemplified above. It may be modified and implemented as appropriate, without compromising its intent. Furthermore, all references listed in this specification. And any publications, regardless of their purpose, shall be incorporated herein by reference in their entirety. ru. [Industrial applicability]

[0072] The lubricating oil composition containing the lubricating oil base oil of the present invention is excellent in cooling performance and fuel efficiency. It can be used for cooling equipment in electric vehicles such as electric cars and hybrid vehicles. It is possible. For example, a small selection from motors, batteries, inverters, and engines. At the very least, it is suitable as a lubricating oil for cooling equipment in an electric vehicle.

Claims

1. %C Ｐ The value is 60 or higher, and the kinematic viscosity at 40°C is 3 mm³. ２ / s is less than cooling lubricant A lubricating oil base oil used in the preparation of lubricating oil compositions.

2. %C Ｐ The value is 60 or higher, and the kinematic viscosity at 40°C is 3 mm³. ２ Base oil (A) that is less than / s It contains, and the content of base oil (A) is 80% by mass or more of the total mass of the lubricating oil base oil. The lubricating oil base oil according to claim 1.

3. The above base oil (A) is further comprising a different base oil (B), The content of the base oil (B) is 1 to 20% by mass relative to the total mass of the lubricating oil base oil. Lubricating oil base oil according to claim 1 or 2.

4. The above-mentioned base oil (A) is an isoparaffin-based base oil, as described in any one of claims 1 to 3. Lubricant base oil.

5. %C Ｎ A lubricating oil base oil according to any one of claims 1 to 4, wherein the ratio is 21 or less.

6. A cooling lubricant composition comprising a lubricating oil base oil according to any one of claims 1 to 5.

7. The content of the lubricating oil base oil is 30% by mass or more of the total mass of the cooling lubricating oil composition. A cooling lubricant composition according to claim 6.

8. The cooling lubricant composition has a kinematic viscosity of 3 mm at 40°C. ２ Claim 6, which is less than / s Or the cooling lubricant composition described in 7.

9. The cooling lubricant composition has a flash point of 90°C or higher, according to any one of claims 6 to 8. The cooling lubricant composition described above.

10. The cooling lubricant composition has a pour point of -45°C or lower, any one of claims 6 to 9. The cooling lubricant composition described above.

11. A cooling lubricant according to any one of claims 6 to 10, used for cooling equipment for electric vehicles. Lubricating oil composition.

12. The aforementioned electric vehicle equipment is selected from a motor, battery, inverter, and engine. A cooling lubricant composition according to claim 11, wherein at least one of the selected components is present.

13. A cooling device for cooling equipment for electric vehicles, wherein any one of claims 6 to 12 An apparatus comprising the cooling lubricant composition described above.

14. A method for cooling equipment for electric vehicles, the cooling method according to any one of claims 6 to 12. By circulating the lubricating oil composition within the electric vehicle equipment, the electric vehicle equipment A method that includes cooling.

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