JP7096121B2 - Improvements in and related to the lubricating composition - Google Patents

Description

The present invention relates to a method of reducing low speed ligation (LSPI) events in a direct-foaming, spark-ignited combustion engine, wherein the method is a lubricating composition comprising a combination of molybdenum-containing additives and boron-containing additives. It includes a step of lubricating the crankcase of the engine.

Market demand and government legislation have prompted automakers and others to continually improve fuel economy, reduce CO ₂ emissions across engines, and at the same time maintain performance (horsepower). By using a turbocharger or supercharger to increase the specific output and slowing down the engine by using a higher gear ratio, which is possible by generating higher torque at lower engine speeds. The use of smaller engines, which provide higher output densities and increase air pressure, has allowed engine manufacturers and others to achieve superior performance while reducing friction and pumping losses. However, higher torque at lower engine speeds causes random preignition in the engine at low speeds, a phenomenon known as Low Speed Pre-ignition or LSPI, which is catastrophic. It has been found that it results in extremely high cylinder peak pressures that can lead to engine failure. This possibility of LSPI prevents engine manufacturers and the like from sufficiently optimizing engine torque at lower engine speeds in such smaller high-power engines.
Without going to any particular theory, LSPI is triggered, at least in part, by the self-ignition of droplets containing, for example, engine oil or a mixture of engine oil, fuel and / or deposits. It is possible that the droplets will form a gap in the piston (its piston ring pack and cylinder) into the combustion chamber of the engine while the engine is operating at low speed under high pressure. An engine that enters from (the space between the liner) and has the longest compression process time (for example, an engine with a compression stroke of 7.5 ms (msec) at 4,000 rpm, is 24 msec when operating at 1,250 rpm. May have a compression process). Therefore, it would be advantageous to identify and provide a lubricating oil composition that is resistant to self-ignition and therefore prevents or reduces the occurrence of LSPI.

Several attempts have been made in the art to address this problem. For example, SAE 2013-01-2569 (Investigation of Engine Oil Effect on Abnormal Combustion in Turbocharged Direct Injection-Spark Ignition Engines) (2nd report), Hirano et al.) Conclude that an increase in calcium concentration leads to a higher LSPI frequency. It has also been concluded that increasing zinc dihydrocarbyl dithiophosphate (ZDDP) concentrations can reduce LSPI frequency. SAE 2014-01-2785 ("Engine Oil Development for Preventing Pre-Ignition in Turbocharged Gasoline Engine", Fujimoto, etc.) is a lubricating oil compound. We conclude that reducing the amount of calcium cleaning agent in it is the most effective way to reduce LSPI events. Similarly, it has been concluded that increasing the amount of ZDDP can be effective in reducing the frequency of LSPI. SAE 2015-01-2027 ("Engine Oil Formulation Technology to Prevent Pre-Ignition in Turbocharged Direct Injection Spark Ignition Engines" , Onodera, etc.) can either (a) increase the molybdenum content in the engine oil formulation and decrease the calcium content, and (b) replace calcium in the cleaning agent for the engine oil formulation with magnesium. Also concludes that it was effective in reducing the frequency of LSPI events. WO 2017/011683 discloses a method of reducing the LSPI frequency by using a lubricant having a low sodium content and containing a specific molybdenum-containing compound. WO 2015/171980 is a method of reducing the frequency of LSPI by including at least one boron-containing compound, for example a boron-containing dispersant or a mixture of a boron-containing compound and a dispersant, in a lubricating oil formulation. Is disclosed. However, according to the examples disclosed in WO 2015/171980, in order to achieve a substantial improvement in LSPI frequency, a substantial amount of the calcium cleaner, or even all of it, with a magnesium cleaner. It was necessary to replace it.

Furthermore, the prior art has recognized that a reduction in calcium content and / or an increase in ZDDP content thereof in a lubricating oil formulation can lead to a reduction in LSPI events. However, cleaning agents are often considered to be essential additives for maintaining basic engine oil performance. Therefore, recent efforts to provide lubricating oil formulations that reduce LSPI events have focused on replacing calcium cleaners with alternative cleaners. However, alternative cleaning agents that can provide adequate cleaning activity and sufficient total base value (TBN) can stimulate development efforts. Moreover, the high ZDDP content in the lubricant formulation can lead to other less desirable effects. In particular, increasing the ZDDP concentration often leads to an increase in ash formation and can lead to damage to the catalyst in the engine exhaust system. EP 3 101 095 discloses a lubricating oil composition for reducing LSPI frequency, which comprises calcium and / or magnesium-containing compounds, molybdenum and / or phosphorus-containing compounds, and nitrogen. Contains the ashless dispersant contained. According to the disclosure of EP 3 101 095, the frequency of LSPI events can be reduced by adjusting the relative amounts of calcium, magnesium, molybdenum and phosphorus in the lubricating oil composition.
Therefore, there remains a need for a lubricating oil composition suitable for use in modern direct eruption flower ignition engines that reduces the incidence of LSPI events.

Unexpectedly, the present inventors lubricate the crankcase of a direct-injection-spark ignition internal combustion engine with the lubricating oil composition by using both molybdenum-containing and boron-containing additives in the lubricating oil composition. It has been found that the frequency of LSPI events in the internal combustion engine is substantially reduced when treated. More specifically, the present inventors unexpectedly, when using such a lubricating composition, a lubricating oil composition containing only a molybdenum-containing additive and not containing a boron-containing additive. We have found that there is a synergistic improvement in the reduction of LSPI compared to the use of lubricant compositions of and vice versa.
Accordingly, according to the first aspect, the present invention provides a method of reducing LSPI events in a direct-emission spark ignition internal combustion engine, wherein the method lubricates the crankcase of the engine with a lubricating oil composition. The lubricating oil composition comprises a boron-containing additive and a molybdenum-containing additive, and has a molybdenum content of at least 150 mass ppm (ppm by weight) based on the mass of the lubricating oil composition. It has a boron content of at least 150 mass ppm based on the mass of the lubricating oil composition.
According to the second aspect, the present invention comprises boron-containing in the lubricating oil composition to reduce LSPI events when the lubricating oil composition lubricates the crankcase of a direct injection-spark ignition internal combustion engine. It provides the use of a combination of additive and molybdenum-containing additive, wherein the molybdenum-containing additive has a molybdenum content of at least 150 mass ppm relative to the mass of the lubricating oil composition. The boron-containing additive, which is given to the composition, imparts a boron content of at least 150 mass ppm to the lubricating oil composition relative to the mass of the lubricating oil composition.

As used herein, the following terms and expressions, when used, have the following meanings:
"Hydrocarbyl" means the chemical group of a compound, which usually contains only hydrogen and carbon atoms and is directly attached to the rest of the compound via a single carbon atom, but is hetero. It can contain atoms, provided that the heteroatom does not impair the intrinsic hydrocarbyl properties of the group;
The terms "oil-soluble" or "oil-dispersible", or synonymous with the term, are not necessarily soluble or soluble in the oil in all proportions of the above compounds or additives. , Does not indicate that it is miscible or can be suspended therein. However, these things allow the compound to be soluble or stablely dispersed, for example, in the oil, to a degree sufficient to exert its intended effect in the environment in which the oil is used. Certainly means. In addition, the additional incorporation of other additives allows the incorporation of other additives and, if desired, higher levels of incorporation of specific additives;
"Major amount" means more than 50% by weight of a composition;
"Minor amount" means 50% by weight or less of a composition;
An "antifoam" is a chemical additive that reduces and impedes the formation of foam in the lubricating oil composition, and examples of commonly used defoaming agents are polydimethylsiloxane and other silicones. , Specific alcohols, stearate and glycols;

"TBN" is the unit mgKOH / g and means the total base value as measured by ASTM D2896;
"Phosphorus content" is measured by ASTM D5185;
"Molybdenum content" is measured by ASTM D5185;
"Boron content" is measured by ASTM D5185;
"Sulfur content" is measured by ASTM D2622;
"Sulfate ash content" is measured by ASTM D874.
Similarly, the various components used, essential as well as optional and customary, may react under compounding, storage or use conditions, and the present invention may be obtained as a result of any such reaction. It will be understood to include the use of possible or obtained products. Further, it is understood that any upper and lower limits of quantities, ranges and ratios described herein can be combined independently. Furthermore, the components according to the invention can be isolated or present in the mixture and can remain within the scope of the invention.
Of course, it will be appreciated that the features described in relation to one aspect of the invention can be incorporated into other aspects of the invention. For example, the use of the present invention can accept any of the features described with respect to the methods of the present invention, and vice versa.

FIG. 1 shows the results of the LSPI test according to Example 3 in the matrix format.

Several jargon have been spark ignited, including knocking, extreme knock (often also called super knock or mega knock), surface ignition, and preignition (ignition that precedes spark ignition). It exists for various forms of abnormal combustion in internal combustion engines. Extreme knocking occurs in a manner similar to conventional knocking, but with high knocking amplitude and can be mitigated by utilizing traditional knocking control methods. LSPI occurs at low speeds and high loads. In LSPI, the initial combustion is relatively slow and similar to normal combustion, with a sudden increase in combustion rate. LSPI, unlike some other types of anomalous combustion, is not a runaway phenomenon. Occurrence of LSPI is difficult to predict, but is often periodic in nature.
LSPI is most likely to occur in direct-injected, supercharged (turbo-supercharged or super-supercharged), spark-ignited (gasoline) internal combustion engines, which have approximately 1,000 to approximately 2,500 revolutions during their operation. At engine speeds of / minute (rpm), for example, engine speeds of about 1,000 to about 2,000 rpm, it exceeds about 1,500 kPa (15 bar) (peak torque), for example at least about 1,800 kPa (18 bar), especially at least about 2,000 kPa (20 bar). ) Brake mean effective pressure is generated. As used herein, the brake mean effective pressure (BMEP) is the mean effective pressure calculated from the measured brake torque. The term "brake" means the actual torque or power available in the flywheel of the engine, as measured by a dynamometer. Therefore, BMEP is a measure of useful power output of the engine. BMEP is defined as the work achieved during one engine cycle divided by the stroke volume of the engine, the engine torque standardized by the engine displacement, and can be calculated using the following equation:
BMEP = 2πTn _c / V _d
Where T is the torque (Nm), n _c is the number of revolutions per cycle, and V _d is the displacement (m ³ ). For a 4-stroke engine, n _c is 2, and for a 2-stroke engine, n _c is 1.

In SAE 2014-01-2785, the frequency of LSPI events is strongly influenced by the calcium content of the lubricating oil composition, and in order to avoid an excessively high frequency of LSPI events, the lubricating oil composition is used. We conclude that it is preferable to avoid the calcium content of the lubricating composition in excess of 0.11% by weight on a mass basis.
Surprisingly, the inventors have found that the presence of a combination of molybdenum and boron in a lubricating oil formulation is effective in reducing the incidence of LSPI events. Unexpectedly, the combination of both molybdenum and boron provides a synergistic improvement in the reduction of LSPI events, the reduction in frequency with respect to molybdenum-only lubricating oil compositions and boron-only compositions. It was found that the value was larger than expected from the analysis of. By lubricating the crankcase of an engine with the lubricating oil composition containing at least 150 mass ppm of molybdenum and at least 150 mass ppm of boron relative to the mass of the lubricating oil composition, the 150 mass of the crankcase It has now been found that the incidence of LSPI in the engine can be reduced compared to lubrication with lubricating oil compositions containing less than ppm molybdenum and less than 150 mass ppm boron. In addition, the present inventors have described, for example, when the method and use according to the first and second aspects of the present invention indicate that the lubricating oil composition contains a considerable amount of calcium, for example, the lubricating oil composition. Concomitantly found to be effective in reducing the frequency of LSPI events, even when containing at least 0.08% by weight of calcium relative to the mass of the lubricating oil composition.
Preferably, the engine according to the method of the first aspect of the invention and / or the use of the second aspect of the present invention has an engine speed of 1,000 to 2,500 rpm (rpm) and optionally 1,000 to 2,000 rpm. It is an engine that produces a brake mean effective pressure level that exceeds 1,500 kPa and optionally exceeds 2,000 kPa.

Optionally, the lubricating oil composition according to all aspects of the present invention is at least 175% by mass of molybdenum, preferably at least 300% by mass of molybdenum, and optionally at least 350% by mass of molybdenum based on the mass of the lubricating oil composition. Molybdenum, eg, at least 500 mass ppm of molybdenum, eg at least 700 mass ppm of molybdenum. Optionally, the lubricating oil composition is molybdenum of 1,500 mass ppm or less, preferably 1,400 mass ppm or less, for example, molybdenum of 1,200 mass ppm or less, for example 1,100 mass ppm or less, based on the mass of the lubricating oil composition. Contains molybdenum, optionally molybdenum of 1,000 mass ppm or less. Optionally, the lubricating oil composition is 150 to 1,500 mass ppm of molybdenum, preferably 175 to 1,500 mass ppm of molybdenum, optionally 300 to 1,400 mass ppm of molybdenum, eg 350. It contains up to 1,200 mass ppm of molybdenum, for example 500 to 1,100 mass ppm of molybdenum, and optionally 700 to 1,000 mass ppm of molybdenum.
Optionally, the lubricating oil composition comprises at least 200% by weight of boron, preferably at least 300% by weight of boron, such as at least 400% by weight of boron, based on the mass of the lubricating oil composition. Optionally, the lubricating oil composition contains boron of 1,500 mass ppm or less, preferably 1,000 mass ppm or less, for example, boron of 800 mass ppm or less, based on the mass of the composition. Optionally, the lubricating oil composition contains 150 to 1,500 mass ppm of boron, preferably 200 to 1,000 mass ppm of boron, and optionally 400 to 800 mass ppm of boron based on the mass of the lubricating oil composition.

は700～1,250の範囲にある。付随的にまたはその代わりに、ホウ酸化分散剤は、以下に記載される無灰分散剤を、公知のホウ酸化手段または技術を利用してホウ酸化することにより製造される。 It will be appreciated that the boron-containing additive may be any suitable oil-soluble compound or oil-dispersible compound. Boron-containing additives can be produced by reacting a boron compound with an oil-soluble or oil-dispersible additive or compound. Boron compounds include boron oxide, boron oxide hydrate, boron trioxide, boron trifluoride, boron tribromide, boron trichloride, boronic acids such as boric acid, boric acid, tetraboric acid and metaboric acid, boron hydride, Includes various esters of boron amide and boric acid. For example, the boron-containing additive is a booxide dispersant; a booxide dispersant viscosity index improver; an alkali metal or mixed alkali metal or an alkaline earth metal borate; a booxidized and overbasified metal cleaning agent. It can be one or more of booxide epoxiside; borate ester; sulfurized borate ester; and borate amide. Preferably, the boron-containing additive is one or more of a boric acid dispersant, a boric acid ester or a borated and overbasified metal cleaner. Optionally, the borooxidized and overbasified metal cleaner, if present, is a borooxidized and overbasified metal cleaner having a TBN of at least 150, eg, borooxidized and over-oxidized with a TBN of at least 150. It is a basicized calcium cleaner.
Booxide dispersants can be prepared by boring succinimides, succinates, benzylamides and derivatives thereof, each having an alkyl or alkenyl group with a molecular weight of 700-3,000. Methods of producing these additives are known to those of skill in the art. The preferred amount of boron contained in these dispersants is 0.1-5% by mass (particularly 0.2-2% by mass). A particularly preferred booxide dispersant is a succinimide derivative of boron, such as polyisobutenyl succinimide booxide. An example of a booxide dispersant is polyisobutenyl succinimide booxide, where the number average molecular weight of the polybutenyl backbone:

Is in the range of 700 to 1,250. Concomitantly or instead, boring dispersants are produced by boring the ashless dispersants described below using known boring means or techniques.

Ash-free dispersants are non-metallic organic substances, which, in contrast to metal-containing and hence ash-forming substances, do not form substantially ash upon combustion. These include long chain hydrocarbons with polar heads, the polarity of which is derived from containing, for example, O, P or N atoms. The hydrocarbon is a lipophilic group that is oil soluble, eg, has 40-500 carbon atoms. Thus, the ashless dispersant can include an oil-soluble polymer-based hydrocarbon backbone with functional groups capable of binding to the particles to be dispersed. Typically, the dispersant often comprises an amine, alcohol, amide or ester-based polar moiety attached to the polymer backbone via a bridging group. For example, ashless dispersants are described in, for example, US-A-3,442,808, oil-soluble salts of long-chain hydrocarbons-substituted mono- and di-carboxylic acids or their anhydrides, esters, amino esters, amides, imides. And oxazoline; thiocarboxylate derivatives of long-chain hydrocarbons; long-chain aliphatic hydrocarbons with directly bound polyamines, and Mannich condensation formed by the condensation of long-chain substituted phenols with formaldehyde and alkylene polyamines. You can choose from the products. The oil-soluble polymer-based hydrocarbon main chain is typically an olefin polymer or polyene, particularly a large molar amount (ie, greater than 50 mol%) of C ₂ to C ₁₈ olefins (eg, ethylene, propylene, butylene, etc.). Isobutylene, pentene, octane-1, styrene), and typically polymers containing C ₂ to C ₅ olefins. The oil-soluble polymer-based hydrocarbon backbone can be homopolymer-based, including, for example, a copolymer of ethylene and an α-olefin, such as propylene or butylene, or a copolymer of two different α-olefins. Preferred classes of olefin polymers include polybutenes, especially polyisobutenes (PIBs) or poly-n-butenes, which can be produced, for example, by polymerization of a C ₄ refinery stream. Other categories of olefin polymers include ethylene-α-olefin (EAO) copolymers and α-olefin homo- and co-polymers.

The ashless dispersant comprises, for example, a derivative of a long chain hydrocarbon-substituted carboxylic acid, an example of which is a derivative of a high molecular weight hydrocarbyl-substituted succinic acid. A notable group of dispersants are, for example, the above-mentioned acids (or derivatives) and nitrogen-containing compounds, preferably hydrocarbon-substituted succinimides produced by reaction with polyalkylene polyamines, such as polyethylene polyamines. Particularly preferred are reaction products of polyalkylene polyamines with alkenyl succinic anhydride, such as US-A-3,202,678; -3,154,560; -3,172,892; -3,024,195; -3,024,237; -3,219,666; and -3,216,936; and BE-A. -It is described in 66,875. A preferred dispersant is a polyalkene-substituted succinimide, wherein the polyalkene group has a number average molecular weight in the range of 900-5,000. The number average molecular weight is measured by gel permeation chromatography (GPC). The polyalkene group can contain large molar amounts (ie, greater than 50 mol%) of C ₂ to C ₁₈ alkenes such as ethene, propene, butene, isobutylene, pentane, octane-1 and styrene. Preferably, the alkene is a C ₂ to C ₅ alkene, more preferably butene or isobutene, which can be produced, for example, by polymerization of a C ₄ purified stream. Most preferably, the number average molecular weight of the polyalkene group is in the range of 950-2,800.
The above ashless dispersants are post-treated with boron by methods known in the art, such as those described in US-A-3,087,936, US-A-3,254,025 and US-A-5,430,105. It is used as an oxidation dispersant. Boronization is an amount of boron oxide, boron halides, boronic acid and boronic acid, for example sufficient to provide an acyl nitrogen-containing dispersant with an atomic ratio of boron of about 0.1 to about 20 per mole of ashless dispersant. It can be achieved by treating with a boron compound selected from the esters of.

Alkaline metals and alkaline earth metal borates are generally hydrated granular metal borates, which are known in the art. Alkali metal borates include mixed alkalis and alkaline earth metal borates. These metal borates are available as commercial products. Representative patents describing suitable alkali metal and alkaline earth metal borates and methods of their manufacture include US3,997,454; 3,819,521; 3,853.772; 3,907,601; 3,997,454; and 4,089,790.
Amine booxide can be produced by reacting one or more of the above-mentioned boron compounds with one or more fatty amines, such as amines with 4-18 carbon atoms. These are the amine and the boron compound at a temperature in the range of 50 to 300 ° C., preferably 100 to 250 ° C. and at a ratio of the equivalent of the amine to the equivalent of the boron compound of 3: 1 to 1: 3. Can be produced by reacting.
Epoxide booxide is generally the reaction product of one or more of the above boron compounds with at least one epoxiside. The epoxiside is generally an aliphatic epoxiside having 8 to 30, preferably 10 to 24, and more preferably 12 to 20 carbon atoms. Examples of useful aliphatic epoxisides include heptyl epoxiside and octyl epoxiside. Similarly, a mixture of epoxisides, such as a commercially available mixture of epoxisides with 14-16 carbon atoms and 14-18 carbon atoms, can also be used. The booxide aliphatic epoxiside is generally known and is described in US Pat. No. 4,584,115.

Boric acid esters can be produced by reacting one or more of the above boron compounds with one or more of alcohols having appropriate lipophilicity. Typically, the alcohol contains 6 to 30 or 8 to 24 carbon atoms. Methods for producing such boric acid esters are known in the art. The boric acid ester can be a boric acid phospholipid. Such compounds, and methods for producing such compounds, are described in EP-A-0 684 298. Similarly, examples of sulfurized and booxidized esters are also known in the art, see EP-A-0 285 455 and US-B-6, 028, 210. Alternatively, the boric acid ester may be substantially absent in the lubricating oil composition according to the method or use of the present invention.
Borated and overbasified metal cleaners are known in the art, where the borate of the cleaner partially or completely replaces its carbonate within the core of the cleaner. .. The boric detergent can be produced by any conventional method, for example, the boric detergent can be produced by treating the metal detergent with boric acid. Suitable booxide cleaners and methods of making them are described in US 3,480,548, US 3,679,584, US 3,829,381, US 3,909,691 and US 4,965,004.
Preferably, at least a portion, eg, most of, the boron content of the lubricating oil composition is provided by the boron-containing dispersible additive. In one embodiment of the present invention, 100% by mass of boron in the lubricating oil composition is based on one or more boron-containing dispersible additives based on the mass of boron in the lubricating oil composition. Given.

Alternatively or further, at least a portion of the boron content of the lubricating oil composition is provided by the boring detergent.
Further or instead, at least a portion of the boron content of the lubricating oil composition is provided by the boric acid ester.
In one aspect of the invention, at least a portion, eg, most of, the boron content of the lubricating oil composition is provided by a boron-containing compound that is not a dispersant.
Optionally, based on the mass of boron in the lubricating oil composition, 100% by mass of boron in the lubricating oil composition is a boron-containing compound that is not one or more dispersants, such as boric acid. Given by detergent and / or boric acid ester. Optionally, based on the mass of boron in the lubricating oil composition, 20% by mass to 100% by mass, preferably 40% by mass to 80% by mass, for example, 50% by mass to 70% of the boron in the lubricating oil composition. %% By weight is given by one or more booxide cleaning agents (s) and / or borate esters (s).
It will be appreciated that the molybdenum-containing additive may be any suitable oil-soluble or oil-dispersible organic molybdenum compound. Preferably, 100% by mass of the molybdenum content according to the lubricating oil composition is given by the organic molybdenum compound based on the mass of the lubricating oil composition. In general, such molybdenum-containing additives, when present in the lubricating oil composition, exhibit friction conditioning properties. Concomitantly or instead, such molybdenum-containing additives can also impart antioxidant and anti-wear credits to the lubricating oil composition.

To make the molybdenum compound oil-soluble or oil-dispersible, typically one or more ligands are attached to the molybdenum atom in the compound. The binding of the ligand includes binding by electrostatic interaction, as in the case of counter-ion and intermediate binding forms between covalent and electrostatic bonds. The ligands within the same compound may be bound in different ways. For example, one ligand may be covalently bound and another ligand may be electrostatically bound. Preferably, the ligand or each ligand is monoanionic, and examples of such ligands are dithiophosphate, dithiocarbamate, xanthate, carboxylate, thioxanthate, phosphate and hydrocarbyl, preferably alkyl, derivatives thereof. Is.
The molybdenum-containing additive may be mononuclear, dikaryon, trinuclear or tetranuclear. Dikaryon and trinuclear molybdenum compounds are preferred. Where the compound is polynuclear, the compound comprises a molybdenum core consisting of non-metal atoms such as sulfur, oxygen and selenium, preferably essentially sulfur.
In a preferred embodiment, the molybdenum compound is a molybdenum-sulfur compound. Preferably, when the molybdenum-sulfur compound is a polynuclear compound, the ratio of the number of molybdenum atoms in its core to the number of monoanionic ligands that can make the compound oil-soluble or oil-dispersible is 1: 1. More than 1, for example at least 3: 2. The oil solubility or oil-dispersibility of the molybdenum-sulfur compound can be affected by the total number of carbon atoms present in the total ligand of the compound. The total number of carbon atoms present in the total hydrocarbyl group of the ligand of the compound will typically be at least 21, eg 21-800, eg at least 25, at least 30 or at least 35. For example, the number of carbon atoms in each alkyl group will generally be in the range of 1-100, preferably 1-40, and more preferably 3-20.

Examples of suitable organic molybdenum compounds include molybdenum dithiocarbamate, molybdenum dithiophosphate, molybdenum dithiophosphinate, molybdenum xanthate, molybdenum thioxanthate, molybdenum sulfide and the like, and mixtures thereof. Particularly preferred are molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, molybdenum alkylxanthate and molybdenum alkylthioxanthate. One of the particularly preferred organic molybdenum compounds is molybdenum dithiocarbamate. In one aspect of the invention, the oil-soluble or oil-dispersible molybdenum compound comprises either molybdenum dithiocarbamate or molybdenum dithiophosphate or a mixture thereof as the sole source of molybdenum atoms in the lubricating oil composition. There is. In another aspect of the invention, the oil-soluble or oil-dispersible molybdenum compound consists of molybdenum dithiocarbamate as the sole source of molybdenum atoms in the lubricating oil composition.

A suitable dikaryon or dimer type molybdenum dialkyldithiocarbamate is represented by the following formula:

R ₁ to R ₄ mean a linear, branched or aromatic hydrocarbyl group independently having 1 to 24 carbon atoms, and X ₁ to X ₄ independently mean an oxygen atom or a sulfur atom. .. The four hydrocarbyl groups R ₁ to R ₄ may be the same or different from each other.
Other molybdenum-containing additives useful in the above compositions of the present invention are organic molybdenum compound compounds having the formulas Mo (ROCS ₂ ) ₄ and Mo (RSCS ₂ ) ₄ , where R is generally 1 Organic groups selected from the group consisting of alkyl, aryl, aralkyl and alkoxyalkyls with ~ 30 carbon atoms, preferably 2-12 carbon atoms and most preferably alkyls with 2-12 carbon atoms. Is. The dialkyldithiocarbamate of molybdenum is particularly preferred.
In a preferred embodiment, the molybdenum-containing additive is an oil-soluble or oil-dispersible trinuclear molybdenum-sulfur compound. Examples of trinuclear molybdenum-sulfur compounds are described in WO98 / 26030, WO99 / 31113, WO99 / 66013, EP-A-1 138 752, EP-A-1 138 686 and European Patent Application No. 02078011. Each is incorporated herein by reference, particularly in relation to the characteristics of the molybdenum compounds and additives disclosed herein.
Suitable trinuclear organic molybdenum compounds include compounds having the formula: Mo _{3 Sk L n Q z} and mixtures thereof, where L is sufficient to make the compound soluble or dispersible in the above oils. It is an independently selected ligand containing an organic group with a large number of carbon atoms, n is 1 to 4, k varies from 4 to 7, and Q is a neutral electron donating compound such as water. , Amine, alcohol, phosphine and ether, and z is in the range of 0-5 and contains non-chemical quantitative values. A total number of 21 carbon atoms, such as at least 25, at least 30, or at least 35 carbon atoms, should be present in the entire organic group of the ligand.

The above ligands are independently selected from those listed below and mixtures thereof:

There, X, X ₁ , X ₂ and Y are independently selected from the group consisting of oxygen and sulfur, where R ₁ , R ₂ and R are independent of hydrogen and organic groups that may be the same or different. Is selected for. Preferably, the organic group is a hydrocarbyl group, such as an alkyl (eg, the carbon atom attached to the rest of the ligand is primary or secondary), aryl, substituted aryl and ether groups. More preferably, each ligand has the same hydrocarbyl group. More importantly, the organic group of the ligand has a sufficient number of carbon atoms to make the compound soluble or dispersible in the oil. For example, the number of carbon atoms in each group will generally be in the range of about 1 to about 100, preferably about 1 to about 30, and more preferably about 4 to about 20. Preferred ligands include dialkyldithiophosphate, alkylxanthate and dialkyldithiocarbamate, of which dialkyldithiocarbamate is more preferred. An organic ligand containing 2 or 3 or more of the functionalities can also act as a ligand and bind to 1 or 2 or more of the core. Those skilled in the art will recognize that the formation of a compound according to the above lubricating oil composition of the present invention requires the selection of a ligand having an appropriate charge to balance the charge of its core.

Particularly suitable molybdenum-containing additives have a cationic core surrounded by an anionic ligand, have the formula: Mo _{3 Sk L n Q z} , and are also represented by a structure such as: Contains compounds with a net charge of +4:

After all, in order to solubilize these cores, the total charge in all of the above ligands must be -4. Four monoanionic ligands are preferred. I am not bound by any theory, but two or more trinuclear cores can be bound or interconnected by one or more ligands, which are polydentate ligands. It is considered to be gained. This includes the case of multicoordinated ligands involving multiple linkages to a single core. It is believed that oxygen and / or selenium can replace the sulfur in the core (s).
Concomitantly or instead, a particularly suitable trinuclear molybdenum-containing additive can be expressed by the formula: Mo _{3 Sk} E _x L _{n App} Q _z , in which.
k is an integer of at least 1;
E represents a non-metal atom selected from oxygen and selenium;
x can be 0 or an integer, and preferably k + x is at least 4, more preferably 4-10, for example in the range 4-7, most preferably 4 or 7;
L represents a ligand that imparts oil solubility or oil-dispersity to the molybdenum-sulfur compound, and L is preferably a monoanionic ligand;
n is an integer in the range 1-4;
A represents an anion other than L when L is an anionic ligand;
p can be 0 or an integer;
Q represents a neutral electron donating compound; and
z is in the range 0-5 and includes non-stoichiometric values.

Those skilled in the art will appreciate that the formation of the trinuclear molybdenum-sulfur compound is, for example, by the number of sulfur and E atoms present in the core, i.e. the sulfur atom (s), and the E atom (s) if present. It will be recognized that depending on the total anion charge given, the appropriate ligand (L) and other anions (A) must be selected and, if present, L and A must be -12. .. Examples of Q include water, alcohols, amines, ethers and phosphines. The electron donating compound Q appears to be present solely to fill any free coordination site on the trinuclear molybdenum-sulfur compound. Examples of A can have any valence, such as monovalent and divalent, and also include disulfides, hydroxydos, alcoholides, amides and thiocyanates or derivatives thereof, preferably representing disulfide ions. Preferably, L is a monoanionic ligand such as dithiophosphate, dithiocarbamate, xanthate, carboxylate, thioxanthate, phosphate and hydrocarbyl, preferably alkyl, derivatives thereof. If n is 2 or 3 or more, the ligands can be the same or different. In one embodiment, independent of the other, k is 4 or 7, n is either 1 or 2, L is a monoanionic ligand, and p is based on the anionic charge on A. , An integer that gives the compound electrical neutrality, and x and z are each 0.
In a further aspect, independent of the other aspects, k is 4 or 7, L is a monoanionic ligand, n is 4, and p, x, and z are each 0.

In another embodiment, the molybdenum-containing additive comprises a trinuclear molybdenum core and a ligand bound to the core, preferably a monoanionic ligand, which can make the core oil-soluble or oil-dispersible, eg. Contains dithiocarbamate. For the avoidance of doubt, the molybdenum-containing additive may also include either negatively charged molybdenum species or positively charged molybdenum species or both negatively and positively charged molybdenum species.
The molybdenum-sulfur core, eg, the structure depicted in (I) and (II) above, can be attached to one or more polydentate ligand-type ligands, i.e., two or more molybdenum atoms. It is possible to form an oligomer by linking with each other by a ligand having a functional group of. It is considered that the molybdenum-sulfur additive containing such an oligomer falls within the range of the above-mentioned lubricating oil composition according to the present invention.
Oil-soluble or oil-dispersible trinuclear molybdenum-containing additives can be used in suitable liquids (s) / solvents (s) in molybdenum sources such as (NH ₄ ) ₂ Mo ₃ S ₁₃ · n. Manufactured by reacting (H ₂ O) (where n fluctuates between 0 and 2 and also contains non-chemical quantitative values) with a suitable ligand source, such as tetraalkyl molybdenum disulfide. can do. Other oils-soluble or dispersible trinuclear molybdenum-containing additives are molybdenum sources such as (NH ₄ ) ₂ Mo ₃ S ₁₃ · n (H ₂ O) in a suitable solvent (s). , Tetraalkylthiumum disulfide, dialkyldithiocarbamate or dialkyldithiophosphate, and can be formed during the reaction of sulfur abstractors such as cyanide ion, sulfite ion or substituted phosphine. Alternatively, trinuclear molybdenum-sulfur halide salts, such as [M'] ₂ [Mo ₃ S ₇ A ₆ ] (where M'is a counterion and A is a halogen such as Cl, Br or I). Reacting with a ligand source such as dialkyldithiocarbamate or dialkyldithiophosphate in a suitable liquid (s) / solvent (s) to form an oil-soluble or dispersible trinuclear molybdenum compound. Can be done. The suitable liquid / solvent can be, for example, aqueous or organic.

The oil-solubility or dispersibility of a compound can be affected by the number of carbon atoms in the organic group of the ligand. Preferably, at least 21 total carbon atoms should be present within the organic group of all the ligands. Preferably, the selected ligand source has a sufficient number of carbon atoms in its organic group to make the compound soluble or dispersible in the lubricating oil composition.
Other examples of molybdenum compounds include molybdenum carboxylate and molybdenum-nitrogen complexes, both of which may be sulfurized.
Alternatively, the molybdenum-containing additive may be an acidic molybdenum compound. These compounds will react with basic nitrogen compounds as measured by the titration procedure of ASTM test D-664 or D-2896 and are typically hexavalent. Molybdate, ammonium molybdate, sodium molybdate, potassium molybdate, and other alkali metal molybdates and other molybdates such as sodium hydrogen molybdate, MoOCl ₄ , MoO ₂ Br ₂ , Mo ₂ O ₃ Cl ₆ , Includes molybdate trioxide or similar acidic molybdate compounds.
Alternatively, the lubricating oil composition of the present invention includes, for example, US Pat. Nos. 4,263,152; 4,285,822; 4,283,295; 4,272,387; 4,265,773; 4,261,843; 4,259,195 and Molybdenum can be provided by a molybdenum / sulfur complex of a basic nitrogen compound as described in No. 4,259,194; and WO 94/06897.
Optionally, the lubricant composition comprises one or more molybdenum-containing compounds, which are not friction modifier-based additives (eg, they are used as friction modifier-based additives). Not done). Optionally, at least a portion, eg, most of, the molybdenum content of the lubricant composition is provided by a molybdenum-containing compound that is not a friction modifier.

Optionally, the lubricating oil composition according to all aspects of the present invention has a calcium content of at least 0.08% by mass based on the mass of the lubricating oil composition. The lubricating oil composition according to all aspects of the present invention can have a calcium content of at least 0.10% by mass, preferably at least 0.15% by mass, for example at least 0.18% by mass, based on the mass of the lubricating oil composition. .. Optionally, the lubricating oil composition according to all aspects of the present invention is 0.08% by mass to 0.8% by mass, preferably 0.10% by mass to 0.6% by mass, for example 0.15% by mass, based on the mass of the lubricating oil composition. It has a calcium content of 0.5% by mass, for example 0.18% by mass to 0.3% by mass. It will be appreciated that the use of LSPI-reducing additives in lubricating oil compositions containing higher concentrations of calcium is particularly advantageous.
Optionally, the lubricating oil composition has a magnesium content of 0.12% by mass or less, for example 0.6% by mass or less, for example 0.03% by mass or less, based on the mass of the lubricating oil composition. Optionally, the lubricating oil composition is substantially magnesium-free and has, for example, a magnesium content of about 0.0% by weight based on the mass of the lubricating oil composition.

Conventionally, a lubricating oil composition suitable for use as a motor oil for a passenger vehicle includes an oil having a large amount of lubricating viscosity and a small amount of a performance-enhancing additive containing a cleaning agent. Metal-containing or ash-forming cleaners act as both acid neutralizers and rust inhibitors to reduce or remove deposits, thereby reducing wear and corrosion and extending engine life. do. Detergents generally include a polar head with a long hydrophobic tail. The polar head contains a metal salt of an acidic organic compound. The salt comprises a substantially stoichiometric amount of the metal, where the salt is usually described as a normal salt or a neutral salt and also 0 to less than 150, eg 0 to about 80 or 100. Has total base value or TBN (as can be measured by ASTM D2896). A large amount of metal base can be incorporated by reacting an excess amount of metal compound (eg, oxide or hydroxide) with an acid gas (eg, carbon dioxide). The resulting overbasified cleaning agent comprises a neutralized cleaning agent as the outer layer of a metal base (eg, carbonate) micelle. Such overbasified detergents will have a TBN of 150 or more, and will typically have a TBN of 250-450 or more.

Optionally, the lubricating oil composition comprises a cleaning agent, such as a calcium cleaning agent. Optionally, the cleaning agent is a calcium booxide cleaning agent. Examples of suitable calcium borate cleaners include one or more calcium borate sulfonate cleaners, one or more calcium borate salicylate cleaners, or mixtures thereof. Not limited. Preferably, such a calcium borooxide detergent is a overbasified calcium borooxide detergent. Such a calcium booxide detergent can be produced by any conventional method. For example, the calcium borate cleaning agent can also be produced by treating the calcium cleaning agent with boric acid. Suitable calcium borooxide cleaners and methods for making such calcium borooxide cleaners are disclosed in US 3,480,548, US 3,679,584, US 3,829,381, US 3,909,691 and US 4,965,004. Optionally, the cleaning agent is a overbasified calcium cleaning agent having a total base value (TBN) of, for example, at least 150, preferably at least 200. Preferably, the overbasified calcium cleaner has a TBN of 200-450. It will be appreciated that the composition optionally comprises one or more additional detergents, eg, detergents other than the overbased calcium detergent with a TBN of at least 150. For example, the composition may include a detergent package containing the overbasified calcium detergent. Preferably, the cleaning agent is used in an amount that gives the lubricating oil composition a TBN of about 4 to about 10 mgKOH / g, preferably about 5 to about 8 mgKOH / g. Preferably, the overbasified cleaning agent based on a metal other than calcium is 60% or less, for example 50% or less, of the TBN of the lubricating oil composition provided by the overbasified cleaning agent. Or it is present in an amount that gives 40% or less. Preferably, the lubricating oil composition according to the present invention is a non-calcium-based superbase in an amount that gives about 40% or less of the total TBN given to the lubricating oil composition by the superbasified detergent. Calcified ash-contains cleaning agents. A combination of superbased calcium cleaning agents can be used (eg, two or more overbased calcium phenates, overbased calcium salicylate and overbased sulfonic acid. Contains calcium; or contains 2 or 3 or more calcium cleaning agents, each with over 150 different TBNs). Preferably, the cleaning agent has a TBN of at least about 200, such as about 200 to about 500, preferably at least about 250, such as about 250 to about 500, more preferably at least about 300, such as about 300 to about 450. Or on average would have such a TBN.

Calcium cleaning agents that can be used in all aspects of the invention include oil-soluble, neutral and overbasified calcium salts, phenates, sulfide phenates, thiophosphonates, salicylates and naphthenates and other oils. Contains soluble carboxylates. It will be appreciated that similarly suitable calcium cleaning agents may include other metals, especially alkali metals or alkaline earth metals such as barium, sodium, potassium, lithium, calcium and / or magnesium. The most commonly used additional metals are magnesium and sodium, either or both of which may be present in the calcium cleaner and / or the calcium booxide cleaner. The cleaning agent can optionally include a combination of cleaning agents, whether overbasified or neutral or both.
Sulfonates can be made from sulfonic acids, typically obtained from petroleum rectification or by sulfonated alkyl substituted aromatic hydrocarbons such as those obtained by alkylation of aromatic hydrocarbons. Examples include those obtained by alkylating benzene, toluene, xylene, naphthalene, diphenyl or halogen derivatives thereof, such as chlorobenzene, chlorotoluene and chloronaphthalene. The alkylation can be carried out in the presence of a catalyst using an alkylating agent having more than about 3 to 70 carbon atoms. Generally, the alkaline sulphonate contains about 9 to about 80 or more carbon atoms, preferably about 16 to about 60 carbon atoms per alkyl substituted aromatic moiety.
The oil-soluble sulfonate or alkaline sulfonic acid can be neutralized with oxides, hydroxides, alcoholides, carbonates, carboxylates, sulfides, hydrosulfides, nitrates, borates and ethers of the metals. .. The amount of the metal compound is selected taking into account the desired TBN of the final product, but is typically about 100-220% by weight (preferably at least 125) of the stoichiometrically required amount. It is in the range of mass%).

Metal salts of phenol or phenol sulfide can be produced by reaction with suitable metal compounds such as oxides or hydroxides, and neutral or overbasified products can be obtained by methods well known in the art. .. Phenol sulfide is a reaction of a phenol with a sulfur or sulfur-containing compound such as hydrogen sulfide, sulfur monohalide or sulfur dihalide so that two or more phenols are generally bridged by a sulfur-containing bridge. It can be produced by forming a product that is a mixture of spanned compounds.
Carboxylate cleaning agents, such as salicylates, can be prepared by reacting aromatic carboxylic acids with suitable metal compounds such as oxides or hydroxides, and neutral or overbasified products are well known in the art. It can be obtained by the method of. The aromatic portion of the aromatic carboxylic acid can contain heteroatoms such as nitrogen and oxygen. Preferably, the moiety contains only carbon atoms, more preferably the moiety contains 6 or more carbon atoms, for example benzene is the preferred moiety. The aromatic carboxylic acid can include one or more aromatic moieties condensed or linked via alkylene crosslinks, such as one or more benzene rings. The carboxylic acid moiety can be attached directly or indirectly to the aromatic moiety. Preferably, the carboxylic acid group is directly attached to the carbon atom of the aromatic moiety, eg, the carbon atom on the benzene ring. More preferably, the aromatic moiety also contains a second functional group, such as a hydroxy or sulfonate group, which can be directly or indirectly attached to a carbon atom on the aromatic moiety.
Preferred examples of aromatic carboxylic acids are salicylic acid and its sulfide derivatives, such as hydrocarbyl-substituted salicylic acid and its derivatives. For example, methods of sulfurizing hydrocarbyl-substituted salicylic acid are known to those of skill in the art. Salicylic acid is typically produced by carboxylation of phenoxide, eg, by the Kolbe-Schmitt method, and in that case, generally in a diluent, mixed with uncarboxylated phenol. Will be obtained.

Preferred substituents in oil-soluble salicylic acid are alkyl substituents. In alkyl-substituted salicylic acids, the alkyl group preferably contains 5-100, preferably 9-30, particularly 14-20 carbon atoms. When two or more alkyl groups are present, the average number of carbon atoms in the entire alkyl group is preferably at least 9 to ensure sufficient oil solubility.
Detergents that are generally useful in formulating lubricating oil compositions according to the invention are, for example, US Pat. Nos. 6,153,565; 6,281,179; 6,429,178; and 6,429,178, mixed surfactants. Also included are "hybrid" detergents formed using the system, eg, Fenate / Salicylate, Sulfonate / Fenate, Sulfonate / Salicylate, Sulfonate / Fenate / Salicylate.
Optionally, the cleaning agent comprises calcium phenate, calcium sulfonate and / or calcium salicylate. Optionally, the cleaning agent comprises calcium booxide phenate, calcium booxide sulfonate and / or calcium borate salicylate, preferably calcium borate salicylate.
Optionally, the cleaning agent comprises a plurality of calcium cleaning agents. Optionally, each calcium cleaner is independently calcium phenate, calcium sulfonate or calcium salicylate. Preferably, the cleaning agent is substantially free of any cleaning agent that is not a calcium cleaning agent. In other words, the cleaning agent may consist of one or more calcium cleaning agents. If the cleaning agent is said to contain virtually nothing other than a particular type of cleaning agent, or is said to consist of that particular type of cleaning agent, then the cleaning agent is nonetheless in trace amounts of other. It will be understood that it can contain substances. For example, the cleaning agent may contain another substance with a trace amount derived from the production method used to produce the cleaning agent.

Optionally, at least 75%, eg, at least 90%, eg, at least 95%, of the calcium content of the lubricating oil composition is provided by the cleaning agent. If the calcium content of the lubricating oil composition is primarily provided by the cleaning agent, the cleaning and LSPI properties of the composition may be controlled particularly effectively.
Optionally, the composition also comprises an additional cleaning agent incidentally. Preferably, this additional cleaning agent is substantially free of calcium. Optionally, the additional cleaning agent comprises one or more phenates, sulfonates and / or salicylate cleaning agents. The additional cleaning agent can be a overbased or neutral cleaning agent. Optionally, the additional cleaning agent comprises one or more neutral metal-containing cleaning agents (having a TBN of less than 150). These neutral, metal-based cleaning agents can be magnesium salts or salts of other alkali metals or alkaline earth metals other than calcium. Optionally, 100% of the metal introduced into the lubricating oil composition by the cleaning agent is calcium. Similarly, the additional cleaning agent can include an ash-free (metal-free) cleaning agent, such as the oil-soluble hydrocarbylphenol aldehyde condensate described in US 2005/0277559 A1.
Preferably, the cleaning agent as a whole has a sulfated ash content (SASH) of 0.2 to 2.0% by mass, for example 0.35 to 1.5% by mass or 0.5 to 1.0% by mass, more preferably about 0.6 to about 0.8% by mass, in the lubricating oil composition. ) Is used in the amount given.
Optionally, the composition is one from a list consisting of dispersants, rust preventives, antioxidants, pour point depressants, defoamers, supplemental anti-wear agents, friction modifiers, and viscosity modifiers. Or it contains two or more additives.

Oils having a lubricating viscosity useful in formulating a lubricating oil composition suitable for use in the practice of the present invention are, in terms of viscosity, from light distillate mineral oils to heavy lubricating oils such as gasoline engine oils, inorganic lubrications. It can be in the range of oils and heavy diesel oils. Generally, the viscosity of the oil is measured at 100 ° C. from about 2 mm ² / sec (centistokes) to about 40 mm ² / sec, especially from about 3 mm ² / sec to about 20 mm ² / sec, most preferably about 9 mm. It is in the range of ² / sec to about 17 mm ² / sec.
Natural oils are animal and vegetable oils (eg, castor oil, lard oil); liquid petroleum oils and paraffin-type, naphthen-type and mixed paraffin-naphthen-type hydrorefined, solvent-treated or acid-treated. Contains mineral oil. Oils with a lubricating viscosity derived from coal or shale also serve as useful base oils.
Synthetic lubricants include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and copolymerized olefins (eg polybutylene, polypropylene, propylene-isobutylene copolymers, chlorinated polybutylene, poly (1-hexene), poly). (1-octene), poly (1-decene)); alkylbenzene (eg, dodecylbenzene, tetradecylbenzene, dinonylbenzene, di (2-ethylhexyl) benzene); polyphenyl (eg, biphenyl, terphenyl, alkylation) Polyphenols); and include alkylated diphenyl ethers and alkylated diphenyl sulfides and derivatives, analogs and homologs thereof.
The alkylene oxide polymers and copolymers and derivatives thereof, in which the terminal hydroxyl group is modified by esterification, etherification, etc., constitute another class of known synthetic lubricating oils. These include polyoxyalkylene polymers produced by polymerization of ethylene oxide or propylene oxide, and alkyl and aryl ethers of polyoxyalkylene polymers (eg, methyl-polyisopropylene glycol ethers with a molecular weight of 1,000 or molecular weights of 1,000 to 1,500. Polyethylene glycol diphenyl ethers); and these mono- and poly-carboxylic acid esters such as tetraethylene glycol acetates, mixed C ₃ -C ₈ fatty acid esters and C ₁₃ oxo acid diesters.

Another suitable category of synthetic lubricants is dicarboxylic acids (eg, phthalic acid, succinic acid, alkyl succinic acid and alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linole). Esters of acid dimers, malonic acid, alkylmalonic acid, alkenylmalonic acid) with various alcohols (eg, butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol). including. Specific examples of such esters include dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, A composite ester formed by reacting diicosyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, and 1 mol of sebacic acid with 2 mol of tetraethylene glycol and 2 mol of 2-ethylhexanoic acid. include. Equally useful are synthetic oils derived from Fischer-Tropsch-synthesized hydrocarbons derived by the gas to liquid method, which are usually gas to liquid or "GTL". It is called base oil.
Similarly, esters useful as synthetic oils are those made from C ₅ to C ₁₂ monocarboxylic acids and polyols and polyol esters such as neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol. include.
Silicon-based oils such as polyalkyl-, polyaryl-, polyalkoxy-or polyaryloxy-silicone oils and silicate oils constitute another useful class of synthetic lubricants, such as The oils are tetraethyl silicate, tetraisopropyl silicate, tetra- (2-ethylhexyl) silicate, tetra- (4-methyl-2-ethylhexyl) silicate, tetra- (p-tert-butylphenyl) silicate, hexa- (4-methyl). -2-Ethylhexyl) Disiloxane, poly (methyl) siloxane and poly (methylphenyl) siloxane are included. Other synthetic lubricants include liquid esters of phosphorous-containing acids (eg, diethyl esters of tricresyl phosphate, trioctyl phosphate, decylphosphonic acid) and polymer-based tetrahydrofuran.

Oils with the above lubrication viscosities are Group I (Group I), Group II (Group II), Group III (Group III), Group IV (Group IV) or Group V (Group V) basestock or the above-mentioned basestock. Can include base oil blends. Preferably, the oil having the lubricating viscosity is a Group II, Group III, Group IV or Group V basestock, or a mixture thereof, or a Group I basestock and one or more Group II, Group III, Group IV or Group. It is a mixture with V-based stock. The basestock or basestock blend preferably has a saturated content of at least 65%, more preferably at least 75%, for example at least 85%. Preferably, the basestock or basestock blend is a Group III or higher basestock or a mixture thereof, or a mixture of a Group II basestock and a Group III or higher basestock or a mixture thereof. .. Most preferably, the basestock or basestock blend has a saturated content of greater than 90%. Preferably, the oil or oil blend will have a sulfur content of less than 1% by weight, preferably less than 0.6% by weight, most preferably less than 0.4% by weight, for example less than 0.3% by weight. In a preferred embodiment, at least 30% by weight, preferably at least 50% by weight, more preferably at least 80% by weight of the oil having the lubricating viscosity used in the lubricating oil composition of the present invention is a group III basestock, group. IV basestock, or a mixture of Group II and Group IV basestocks.
Preferably, the volatility of the oil or oil blend as measured by the Noack test (ASTM D5800) is 30% by weight or less, eg less than about 25% by weight, preferably 20% by weight or less. It is more preferably 15% by mass or less, and most preferably 13% by mass or less. Preferably, the oil or oil blend has a viscosity index (VI) of at least 85, preferably at least 100, most preferably about 105-140.

The definition of the basestock and the base oil in the lubricating oil composition according to the present invention is a publication of the American Petroleum Institute (API): "Engine Oil Licensing and Certification System". , Industry Services Department, 14th Edition, December 1996, Addendum 1, identical to that found in December 1998. This publication categorizes the basestock as follows:
a) Group I basestock contains less than 90% saturated and / or more than 0.03% sulfur and has a viscosity index greater than or equal to 80 and less than 120 when using the test method specified in Table 1 below. have.
b) Group II basestock contains 90% or more saturated material and 0.03% or less sulfur, and has a viscosity index of 80 or more and less than 120 when using the test method specified in Table 1 below. ..
c) Group III basestock contains 90% or more saturated material and 0.03% or less sulfur and has a viscosity index of 120 or more when using the test method specified in Table 1 below.
d) The Group IV basestock is a poly-alpha-olefin (PAO). and
e) Group V basestock includes all other basestock not included in Group I, II, III, or IV.

The lubricating oil composition according to all aspects of the present invention may further contain a phosphorus-containing compound.
Suitable phosphorus-containing compounds include metal salts of dihydrocarbyldithiophosphate, which are often used as anti-wear and antioxidants. The metal can be an alkali metal or an alkaline earth metal, or aluminum, lead, tin, molybdenum, manganese, nickel or copper. The zinc salt is most commonly used in lubricating oils in an amount of 0.1 to 10, preferably 0.2 to 2% by mass, based on the total mass of the lubricating oil composition. They first form dihydrocarbyl dithiophosphate (DDPA) by reacting P ₂ S ₅ with one or more alcohols or phenols, usually according to known techniques, and then the formed DDPA is neutralized with a zinc compound. It can be manufactured by summing. For example, dithiophosphate can be produced by reacting a mixture of primary and secondary alcohols. Alternatively, a wide variety of dithiophosphates can be produced, where the hydrocarbyl group of one dithiophosphate is completely secondary in properties, and the hydrocarbyl group of the other dithiophosphate is completely primary in properties. Is. Any basic or neutral zinc compound may be used to produce the zinc salt, but oxides, hydroxides and carbonates thereof are most commonly used. Commercially available additives often contain excess amounts of zinc due to the use of excess amounts of the basic zinc compound in their neutralization reaction.

The preferred zinc dihydrocarbyl dithiophosphate salt is an oil-soluble salt of dihydrocarbyl dithiophosphate and can be represented by the following formula:

Here, R and R'can be hydrocarbyl radicals containing 1 to 18 carbon atoms, preferably 2 to 12 carbon atoms, which are the same or different, and the radicals are, for example, alkyl, alkenyl, aryl, arylalkyl, arca. Includes reels and alicyclic radicals. Particularly preferred as R and R'groups are alkyl groups with 2-8 carbon atoms. Therefore, the radicals are, for example, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl, n-octyl, decyl, dodecyl, octadecyl. , 2-Ethylhexyl, phenyl, butylphenyl, cyclohexyl, methylcyclopentyl, propenyl, butenyl. In order to obtain oil solubility, the total number of carbon atoms (ie, R and R') in the dithiophosphate will generally be about 5 or more. The zinc dihydrocarbyl dithiophosphate (ZDDP) preferably contains a zinc dialkyl dithiophosphate.
Preferably, the lubricating oil composition useful in carrying out the present invention contains a phosphorus-containing compound in 0.01-0.12% by mass of phosphorus, eg, in the lubricating oil composition, relative to the total mass of the lubricating oil composition. It will contain 0.04 to 0.10% by mass of phosphorus, preferably 0.05 to 0.08% by mass of phosphorus in an introduced amount. Optionally, the lubricating oil composition is 0.1% by mass (1,000 ppm) or less, for example 0.09% by mass (900 ppm) or less, preferably 0.08% by mass (800 ppm) or less of phosphorus based on the mass of the lubricating oil composition. Has a content rate. In a preferred embodiment of the present invention, the lubricating oil composition has a phosphorus content of 0.06% by mass (600 ppm) or less.
Antioxidants or antioxidants reduce the tendency of mineral oil to deteriorate during use. Oxidative degradation can be substantiated by sludge in the lubricant, varnish-like deposits on the metal surface, and increased viscosity. Such acid inhibitors include alkaline earth metal salts of hindered phenols, preferably alkylphenol thioesters with C ₅ -C ₁₂ alkyl side chains, calcium nonylphenol sulfides, oil-soluble phenates and sulfide phenates, phosphorus sulfides or sulfide hydrocarbons. Alternatively, it includes esters, phosphorous esters, metal thiocarbamates, oil-soluble copper compounds as described in US Pat. No. 4,867,890, and molybdenum-containing compounds.

Aromatic amines with at least two aromatic groups attached directly to their nitrogen constitute another class of compounds often used for antioxidancy. A typical oil-soluble aromatic amine with at least two aromatic groups attached directly to one amine nitrogen contains 6-16 carbon atoms. The amine can contain 3 or more aromatic groups. It has at least 3 aromatic groups as a whole, where the two aromatic groups are covalently bonded or by an atom or group (eg, oxygen or sulfur atom, or -CO-, -SO _2- , or alkylene group). A compound that is bound and the two are directly attached to one amine nitrogen is also considered to be an aromatic amine with at least two aromatic groups directly attached to that nitrogen. .. Typically, the aromatic ring is substituted with one or more substituents selected from alkyl, cycloalkyl, alkoxy, aryloxy, acyl, acylamino, hydroxy, and nitro groups. The amount of any such oil-soluble aromatic amine having at least two aromatic groups directly attached to one amine nitrogen should preferably not exceed 0.4% by weight.
Dispersants result in oxidation during use and keep substances insoluble in oil in suspension, thus preventing sludge aggregation and precipitation, or deposition on metal parts. Optionally, the lubricating oil composition used according to the present invention may comprise at least one dispersant and may optionally include a plurality of dispersants. The dispersant (s) is preferably a nitrogen-containing dispersant, and is preferably 0.05 to 0.19% by weight, most preferably 0.06 to 0.18% by weight, based on the lubricating oil composition. Gives 0.07-0.16% by weight nitrogen.

Dispersants useful in the context of the present invention, when added to lubricating oils, contain nitrogen-containing materials, which are known to be effective in reducing deposit formation when used in gasoline and diesel engines. Includes a range of ashless (metal-free) dispersants and also contains oil-soluble polymer long chain backbones with functional groups capable of binding to particles to be dispersed. Typically, such dispersants often have an amine, amine-alcohol or amide polar moiety attached to the polymer backbone via a bridging group. The ashless dispersant is, for example, an oil-soluble salt of a long-chain hydrocarbon-substituted mono- and a poly-carboxylic acid or an anhydride thereof, an ester, an amino ester, an amide, an imide and an oxazoline; a thiocarboxylate derivative of a long-chain hydrocarbon; Long-chain aliphatic hydrocarbons with polyamine moieties directly attached to them; and Mannich condensation products formed by the condensation of long-chain substituted phenols with formaldehyde and polyalkylene polyamines. obtain.
In general, each mono- or di-carboxylic acid-producing moiety will react with a nucleophilic group (amine or amide) and the number of functional groups in the polyalkenyl-substituted carboxylic acid-based acylating agent will be. Will determine the number of nucleophilic groups in the finished dispersant.

The polyalkenyl moieties of the dispersants useful in the present invention are between 700 and 3,000, preferably between 950 and 3,000, such as between 950 and 2,800, more preferably about 950 to 2,500, and most preferably between 950 and 2,400. It has a number average molecular weight. In one aspect of the invention, the dispersant of the lubricating oil composition is a lower molecular weight dispersant (eg, having a number average molecular weight of 700-1,100) and at least 1,500, preferably between 1,800 and 3,000, eg. Includes a combination of high molecular weight dispersants with a number average molecular weight of between 2,000 and 2,800, more preferably 2,100 to 2,500, and most preferably 2,150 to 2,400. The molecular weight of a dispersant is generally expressed in terms of the molecular weight of its polyalkenyl moiety, because the exact molecular weight range of the dispersant is the type, functional group of the polymer used to derive the dispersant. It depends on a number of parameters, including the number of and the type of nucleophilic group used.
Preferably, the polyalkenyl moiety from which the high molecular weight dispersant is derived has a narrow molecular weight distribution (MWD), the molecular weight distribution being determined by the ratio of weight average molecular weight (Mw) log average molecular weight (Mn). It is also called polydispersity. Specifically, the polymer from which a dispersant useful in carrying out the present invention is derived has Mw / Mn of 1.5 to 2.0, preferably 1.5 to 1.9, and most preferably 1.6 to 1.8.

Suitable hydrocarbons or polymers used in the formation of dispersants useful in the practice of the present invention include homopolymers, copolymers or lower molecular weight hydrocarbons. A group of such polymers is ethylene and / or at least one of the formula: H ₂ C = CHR ¹ (where R ¹ is a linear or branched alkyl radical containing 1-26 carbon atoms). Contains a polymer of C ₃ -C ₂₈ α-olefin with, wherein the polymer contains carbon-carbon unsaturated, preferably a high degree of terminal ethylidene unsaturated. Preferably, such a polymer comprises a copolymer of ethylene with at least one α-olefin having the above formula, wherein R ¹ is an alkyl having 1-18 carbon atoms, and It is more preferably an alkyl group having 1 to 8 carbon atoms, and even more preferably 1 to 2 carbon atoms. Thus, useful α-olefin monomers and commonomers include, for example, propylene, butene-1, hexene-1, octene-1, 4-methylpentene-1, decene-1, dodecene-1, tridecene-1, tetradecene-1, Includes pentadecene-1, hexadecene-1, heptadecene-1, octadecene-1, nonadecene-1, and mixtures thereof (eg, mixtures of propylene and butene-1). Typical of such polymers are propylene homopolymers, butene-1 homopolymers, ethylene-propylene copolymers, ethylene-butene-1 copolymers, propylene-butene copolymers and the like, wherein the polymers are at least several. Contains terminal and / or internal unsaturated. Preferred polymers are unsaturated copolymers of ethylene with propylene and ethylene with butene-1. The copolymer can contain a small amount, eg 0.5-5 mol%, of a C ₄ -C ₁₈ non-conjugated diolefin comonomer. However, the polymer used in the practice of the present invention preferably contains only α-olefin homopolymers, copolymers of α-olefin commonomers and copolymers of ethylene and α-olefin comonomers. The molar ethylene content of the polymer used in the present invention is preferably in the range of 0-80%, and more preferably 0-60%. When propylene and / or butene-1 is used as a comonomer (s) with ethylene, the ethylene content of such copolymers is most preferably between 15 and 50%, but higher. Or lower ethylene content may also be present.

These polymers are α-olefin monomers, or mixtures of α-olefin monomers, or mixtures containing ethylene with at least one C ₃ -C ₂₈ α-olefin monomer, with at least one metallocene (eg, cyclopentadi). It can be produced by polymerization in the presence of a catalytic system containing an enyl-transition metal compound) and an alumoxane compound. Using this method, more than 95% of the polymer chains can provide a polymer with terminal ethenylidene-type unsaturatedity. The proportion of polymer chains exhibiting terminal ethenylidene unsaturatedity can be determined by FTIR spectroscopy, titration, or ¹³ C NMR. This latter type of copolymer can be characterized by the formula: POLY-C (R ¹ ) = CH ₂ , where R ¹ is C ₁ -C ₂₆ alkyl, preferably C ₁ -C ₁₈ alkyl, and more. It is preferably C ₁ -C ₈ alkyl, and most preferably C ₁ -C ₂ alkyl (eg, methyl or ethyl), where POLY represents the polymer chain. The chain length of the R ¹ alkyl group will vary depending on the comonomer (s) selected for use in the polymerization. A small amount of the polymer chain can contain terminal ethenyl, i.e. vinyl unsaturated, i.e. POLY-CH = CH ₂ , and some of the polymer is internal mono-unsaturated, eg, POLY-CH = CH (R). ¹ ) can be included, where R ¹ is as defined above. These terminally unsaturated copolymers can be produced by known metallocene chemistries, as well as US Pat. Nos. 5,498,809; 5,663,130; 5,705,577; 5,814,715; It can also be manufactured as described in 6,022,929 and 6,030,930.

Another useful class of polymers is polymers produced by cationic polymerization of isobutylene, styrene and the like. Common polymers in this category are C ₄ purified streams with a butene content of 35-75% by weight and an isobutylene content of 30-60% by weight, such as Lewis acid catalysts, such as aluminum trichloride or trifluoride. Contains polyisobutene obtained by polymerization in the presence of boron fluoride. A preferred monomer source for producing poly-n-butene is a petroleum feed stream such as Raffinate II. These feedstocks are disclosed in the art, for example, in US Pat. No. 4,952,739. Polyisobutylene is the most preferred backbone of the polymer useful in the practice of the present invention, in that it is readily available by cation polymerization of the butene stream (eg, using an AlCl ₃ or BF ₃ catalyst). be. Such polyisobutylene contains residual unsaturated in the amount of about one ethylenically double bond per polymer chain, generally arranged along the chain. In a preferred embodiment, polyisobutylene produced from a pure isobutylene stream or a stream of Raffinate I is used to produce a reactive isobutylene polymer with a terminal vinylidene olefin. Preferably, these polymers, called highly reactive polyisobutylene (HR-PIB), have a terminal vinylidene content of at least 65%, such as 70%, more preferably at least 80%, and most preferably at least 85%. The production of such polymers is described, for example, in US Pat. No. 4,152,499. HR-PIB is known and HR-PIB is available on the market under the trade name Glissopal ^TM (from BASF).
Polyisobutylene polymers that can be used are generally based on 700-3,000 hydrocarbon chains. The method for producing polyisobutylene is known. Polyisobutylene can be functionalized by halogenation (eg, chlorination), thermal "ene" reaction, or radical grafting with a catalyst (such as peroxide), as described below.

The hydrocarbon or polymer backbone may be selectively or chained at carbon-carbon unsaturated sites on the polymer or hydrocarbon chain, for example utilizing the three methods described above or combinations thereof in any order. Can be randomly functionalized along with a carboxylic acid-producing moiety (preferably an acid or anhydride moiety).
Methods of reacting polymer hydrocarbons with unsaturated carboxylic acids, anhydrides or esters, and the production of derivatives from such compounds are described in US Pat. No. 3,087,936; 3,172,892; 3,215,707; 3,231,587; 3,272,746; 3,275,554; 3,381,022; 3,442,808; 3,565,804; 3,912,764; 4,110,349; 4,234,435; 5,777,025; 5,891,953; and EP 0 382 450 B1; CA-1,335,895 and GB-A-1,440,219. For example, the polymer or hydrocarbon utilizes the halogen-assisted functionalization (eg, chlorination) method described above or the thermal "ene" reaction described above and uses a carboxylic acid producing moiety (preferably an acid or anhydride). , The polymers or hydrocarbons are subjected to predominantly carbon-carbon unsaturated (also also referred to as ethylene-based or olefin-based unsaturated) sites on these polymers or hydrocarbon chains, with functional moieties or functionalizers, i.e. acids. , Anhydrous, ester moieties and the like can be functionalized by reacting under conditions that result in the addition.

Selective functionalization is performed on the unsaturated α-olefin polymer at a temperature of 60-250 ° C, preferably 110-160 ° C, for example 120-140 ° C, for about 0.5-10 hours, preferably 1-7 hours. Halogenation, eg, chlorination, is achieved by passing chlorine or bromine through the polymer to about 1-8% by weight, preferably 3-7% by weight, chlorine or bromine relative to the mass of the polymer or hydrocarbon. Or it can be achieved by bromination. The halogenated polymer or hydrocarbon (hereinafter the main chain) is then monounsaturated at 100-250 ° C, usually about 180 ° C-235 ° C, for about 0.5-10 hours, eg 3-8 hours. The resulting product of reaction with a sufficient monounsaturated reactant capable of adding a predetermined number of functional moieties to the backbone, such as a carboxylic acid reactant, is the halogenated backbone. It will contain a predetermined number of moles of the monounsaturated carboxylic acid reactant per mole. Alternatively, the backbone and the monounsaturated carboxylic acid reactant are mixed and heated, while chlorine is added to the hot material.
Chlorination helps increase the reactivity of the starting olefin polymer with monounsaturated functionalized reactants, but some of the above polymers or hydrocarbons intended for use in the present invention, especially high end bond content. And reactive, such preferred polymers or hydrocarbons are not required. Thus, preferably, the backbone and the monosaturated functional reactants, such as carboxylic acid reactants, are contacted at high temperatures to cause an initial thermal "ene" reaction. The ene reaction is known.
The hydrocarbon or polymer backbone can be functionalized by a variety of methods by random bonding of functional moieties along the polymer chain. For example, the polymer in solution or solid form can be grafted with the monounsaturated carboxylic acid reactant in the presence of a radical initiator, as described above. When performed in solution, the grafting occurs at high temperatures in the range of about 100-260 ° C, preferably 120-240 ° C. Preferably, radical-initiated grafting is achieved in an inorganic lubricant solution containing, for example, 1-50% by weight, preferably 5-30% by weight of the polymer relative to its initial total oil solution. Will.

The radical initiators that can be used are peroxides, hydroperoxides, and azo compounds, preferably having a boiling point above about 100 ° C. and thermally decomposing within the grafting temperature range to free radicals. It is something to give. Typical of these radical initiators are azobutyronitrile, 2,5-dimethylhex-3-ene-2,5-bis-tert-butyl peroxide and dicumen peroxide. When used, the initiator is typically used in an amount between 0.005% by weight and 1% by weight based on the weight of the reaction mixture solution. Typically, the monounsaturated carboxylic acid reactants and radical initiators described above are used in mass ratios ranging from 1.0: 1 to 30: 1, preferably 3: 1 to 6: 1. The grafting is preferably carried out in an inert atmosphere, for example under a nitrogen gas seal. The resulting grafted polymer is characterized by having randomly bonded carboxylic acid (or ester or anhydride) moieties along the polymer chain, which of course some of the polymer chain. Is understood to remain ungrafted. The radical grafting described above can be used for other polymers and hydrocarbons useful in the practice of the present invention.

Preferred mono-unsaturated reactants used to functionalize the main chain include mono- and di-carboxylic acid substances, ie acids, anhydrides, or acid ester substances, and (i) mono-unsaturated C. ₄ -C ₁₀ dicarboxylic acid, where (a) its carboxyl group is bicinyl (ie, located on an adjacent carbon atom) and (b) at least one of the adjacent carbon atoms, preferably both, are said mono. Part of the unsaturated; (ii) a derivative of (i) above, eg, an anhydride or a mono- or di-ester derived from the C ₁ -C ₅ alcohol of (i); (iii) mono-unsaturated C _3- The C ₁₀ monocarboxylic acid, where its carbon-carbon double bond is conjugated to its carboxy group, i.e. has the structure -C = -CO-; and (iv) the derivative of (iii) above. For example, it includes mono- or di-esters derived from the C ₁ -C ₅ alcohol of (iii). Mixtures of monounsaturated carboxylic acid substances (i)-(iv) can also be used. Upon reaction with the backbone, the monounsaturation of the monounsaturated carboxylic acid reactant is brought to a saturated state. Thus, for example, maleic anhydride is the backbone-substituted succinic acid anhydride, and acrylic acid is the backbone-substituted propionic acid. Typical examples of such monounsaturated carboxylic acid reactants are fumaric acid, itaconic acid, maleic acid, maleic anhydride, chloromaleic acid, chloromaleic acid anhydride, acrylic acid, methacrylic acid, crotonic acid and keihi. Acids, and lower alkyl (eg, C ₁ -C ₄ alkyl) acid esters of the above, such as methylmalate, ethylfumarate, and methylfumarate.
To provide the required functionality described above, the monounsaturated carboxylic acid reactant, preferably maleic anhydride, is typically equimolar to about 100 mass based on the number of moles of polymer or hydrocarbon. It will be used in an amount in the range of% excess, preferably 5-50% by weight. The unreacted excess monounsaturated carboxylic acid reactant can be removed from its final dispersant product, for example, usually by stripping under reduced pressure, if desired.

The functionalized oil-soluble polymer-based hydrocarbon backbone is then derivatized with a nitrogen-containing nucleophilic reactant, such as an amine, aminoalcohol, amide, or a mixture thereof to form the corresponding derivative. .. Amine compounds are preferred. Amine compounds useful for derivatizing functionalized polymers include at least one amine and can also contain one or more additional amines or other reactive or polar groups. These amines can be hydrocarbyl amines, or can be hydrocarbyl amines in which the hydrocarbyl group predominantly contains other groups such as hydroxy groups, alkoxy groups, amide groups, nitriles, imidazoline groups and the like. Particularly useful amine compounds include mono- and poly-amines, such as 1-12, eg 3-12, preferably 3-9, most preferably 6-about 7 nitrogen atoms per molecule, 2 Includes polyalkenes and polyoxyalkylene polyamines having up to 60, eg, 2-40 (eg, 3-20) total carbon atoms. Mixtures of amine compounds, such as those produced by the reaction of alkylene dihalides with ammonia, may be advantageously used. Preferred amines are aliphatic saturated amines, such as 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, polyethyleneamine, such as diethylenetriamine, triethylenetetramine, etc. Includes tetraethylenepentamine, and polypropylene amines such as 1,2-propylenediamine, and di- (1,2-propylene) triamine. Such polyamine mixtures, known as PAM, are available on the market. A particularly preferred polyamine mixture is a mixture derived by distilling a light fraction from a PAM product. This resulting mixture, known as "heavy" PAM or HPAM, is also available on the market. The characteristics and attributes of both PAM and / or HPAM are, for example, US Pat. No. 4,938,881; No. 4,927,551; No. 5,230,714; No. 5,241,003; No. 5,565,128; No. 5,756,431; No. 5,792,730; It is described in No. 5,854,186 of the same.

Other useful amine compounds include alicyclic diamines such as 1,4-di (aminomethyl) cyclohexane and heterocyclic nitrogen compounds such as imidazoline. Another useful class of amines are polyamides and related amidoamines as disclosed in US Pat. Nos. 4,857,217; 4,956,107; 4,963,275; and 5,229,022. Also usable are tris (hydroxymethyl) aminomethane (TAM) as described in US Pat. No. 4,102,798; No. 4,113,639; No. 4,116,876; and No. 989,409 in the United Kingdom. Dendrimers, star-type amines, and amines with a comb-type structure can also be used. Similarly, condensed amines as described in US Pat. No. 5,053,152 can also be used. The functionalized polymer is reacted with the amine compound using, for example, US Pat. Nos. 4,234,435 and 5,229,022, as well as prior art as described in EP-A-208,560.
A preferred dispersant composition comprises at least one polyalkenyl succinimide, which is the reaction product of a polyalkenyl-substituted succinic anhydride (eg, PIBSA) and a polyamine (PAM), from 0.65 to 0.65. It has a coupling ratio of 1.25, preferably 0.8 to 1.1, most preferably 0.9 to 1. In the context of the present disclosure, "coupling ratio" can be defined as the ratio of the number of succinyl groups in the PIBSA to the number of primary amino groups in the polyamine reactant.
Another class of high molecular weight ashless dispersants include the Mannich base condensation product. Generally, as disclosed, for example, in US Pat. No. 3,442,808, these products are about 1 mol of long-chain alkyl-substituted mono- or poly-hydroxybenzene and about 1-2.5 mol of carbonyl compound (1 or). Produced by condensing (eg, formaldehyde and paraformaldehyde) and 0.5-2 mol of polyalkylene polyamine. Such Mannig base condensation products can contain the polymer products produced by metallocene-catalyzed polymerization as substituents on their benzene groups, or in a manner similar to that described in US Pat. No. 3,442,808. , Can be reacted with compounds containing such polymers substituted on amber acid anhydride. Examples of functionalized and / or derivatized olefin polymers synthesized using metallocene catalyst systems are described in the publications identified above.

The dispersant (s) are preferably non-polymeric (eg, mono- or bis-succinimide). The dispersant (s), especially the lower molecular weight dispersants, can optionally be booxidized. Such dispersants can generally be booxidized by conventional means as taught in US Pat. Nos. 3,087,936, 3,254,025 and 5,430,105. Boronization of the dispersant is an amount of the boron compound, eg, boron oxide, sufficient to give the acyl nitrogen-containing dispersant 0.1-20 atomic ratios of boron per mole of the acylated nitrogen formulation. , Easily achieved by treatment with boron halides, boronic acids, and esters of boronic acids.
The highly reactive polyisobutylene-derived dispersants have been found to provide a lubricant composition with wear credit compared to the corresponding dispersants derived from conventional polyisobutylene. .. This wear reliability is particularly important for lubricants containing low levels of ash-containing wear inhibitors, such as ZDDP. Therefore, in a preferred embodiment, the at least one dispersant used in the lubricating oil composition of the present invention is derived from highly reactive polyisobutylene.
Additional additives can be incorporated into the lubricating oil compositions to meet specific performance requirements. Examples of additives that can be included in the lubricating oil composition of the present invention include metal corrosion inhibitors, viscosity index improvers, rust inhibitors, antioxidants, friction modifiers, defoamers, anti-wear agents and It is a pour point defoamer. Some of them are discussed in more detail below.

It is also possible to include friction modifiers and fuel economy agents that are compatible with the other components of the final oil. Examples of such substances are glyceryl monoesters of higher fatty acids such as glyceryl monooleates; esters of long-chain polycarboxylic acids and diols such as butanediol esters of dimerized unsaturated fatty acids; oxazoline compounds; and alkoxyls. Includes modified and alkyl-substituted monoamines, diamines and alkyl ether amines such as ethoxylated taro amines and ethoxylated taro ether amines.
The viscosity index of the base stock is increased or improved by incorporating a specific polymer-based substance that functions as a viscosity modifier (VM) or a viscosity index improver (VII). In general, polymer-based substances useful as viscosity modifiers have a number average molecular weight (Mn) of about 5,000 to about 250,000, preferably about 15,000 to about 200,000, more preferably about 20,000 to about 150,000. These viscosity modifiers can be grafted with a grafted material such as maleic anhydride, and the grafted material can be used to form a polyfunctional viscosity modifier (dispersant-viscosity modifier). Can be reacted with, for example, amines, amides, nitrogen-containing heterocyclic compounds or alcohols. The molecular weight of the polymer, especially Mn, can be determined by various known techniques. A preferred method is gel permeation chromatography (GPC), which also provides information on the molecular weight distribution incidentally (WWYau, JJKirkl & DDBly, "Modern Size Exclusion Liquid Chromatography". ) ”, John Wiley and Sons, NY, 1979). In particular, another method useful for measuring molecular weight for lower molecular weight polymers is the vapor pressure osmotic method (see, eg, ASTM D3592).

It has been found that some diblock copolymers useful as viscosity modifiers provide wear reliability relative to, for example, olefin copolymer viscosity regulators. This wear reliability is particularly important for lubricants containing low levels of ash-containing wear inhibitors, such as ZDDP. Therefore, in a preferred embodiment, the at least one viscosity modifier used in the lubricating oil composition of the present invention is predominantly, preferably one block derived exclusively from vinyl aromatic hydrocarbon monomers and predominantly preferred. A linear diblock copolymer containing one block derived exclusively from a diene monomer. Useful vinyl aromatic hydrocarbon monomers include those containing 8 to about 16 carbon atoms, such as aryl-substituted styrene, alkoxy-substituted styrene, vinylnaphthalene, alkyl-substituted vinylnaphthalene and the like. A diene or diolefin contains two double bonds that are usually located in a 1,3 relationship in a conjugated state. An olefin containing three or more double bonds, often referred to as a polyene, is considered to fall within the definition of "diene" as used herein as well. Useful dienes contain 4 to about 12 carbon atoms, preferably 8 to about 16 carbon atoms, such as 1,3-butadiene, isoprene, piperylene, methylpentadiene, phenylbutadiene, 3,4-dimethyl. It contains -1,3-hexadiene, 4,5-diethyl-1,3-octadiene, preferably 1,3-butadiene and isoprene.
As used herein in the context of the composition of a polymer block, "exclusively" means that the specified monomer or monomer type that is the main component of the polymer block is present in an amount of at least 85% by weight of the block. Means to do.

Polymers made with diolefins will contain ethylene-based unsaturateds, and such polymers are preferably hydrogenated. If the polymer is hydrogenated, the hydrogenation can be achieved using any of the techniques known in the prior art. For example, the hydrogenation uses methods such as those taught in US Pat. Nos. 3,113,986 and 3,700,633, for example so that both ethylenically and aromatic unsaturateds are converted (saturated). The hydrogenation can be achieved, for example, as taught in US Pat. Nos. 3,634,595; 3,670,054; 3,700,633 and USRe 27,145, where a significant portion of the ethylenically unsaturated is present. It can be selectively achieved so that it is converted, while little or no aromatic unsaturatedity is converted. Any of these methods can also be used to hydrogenate polymers that contain only ethylenically unsaturated and not aromatic unsaturateds.
The block copolymers are a mixture of linear diblock polymers with different molecular weights and / or different vinyl aromatic contents, as described above, and a mixture of linear block copolymers with different molecular weights and / or different vinyl aromatic contents. Can be included. The use of two or more different polymers, when used to produce compounded engine oils, may be preferred over a single polymer, depending on the rheological properties that the product intends to impart. Examples of commercially available styrene / hydrogenated isoprene linear diblock copolymers are Infineum USA LP and Infineum UK Ltd., Infineum SV140 ^TM , Infinium. SV150 (Infineum SV150 ^TM ) and Infineum SV160 (Infineum SV160 ^TM ); Lubrizol 7318 (Lubrizol ^TM 7318) available from The Lubrizol Corporation; and Septon Company of America (Kuraray) Includes Septon 1001 ^TM and Septon 1020 ^TM available from Group)). Suitable styrene / 1,3-butadiene hydrogenated block copolymers are marketed by BASF under the trade name Glissoviscal ^TM .

Pour point depressants (PPDs) are also known as lubricant fluidity improvers (LOFIs), which lower the temperature. Compared to VMs, LOFIs generally have a lower number average molecular weight. Like VMs, LOFIs can be grafted with a grafted material such as maleic anhydride, which grafted material reacts with, for example, amines, amides, nitrogen-containing heterocyclic compounds or alcohols. And form a polyfunctional additive.
In the above lubricating oil composition of the present invention, it may be necessary to include an additive that maintains the stability of the viscosity of the blend. Thus, polar group-containing additives achieve reasonably low viscosities during their pre-blending step, but some compositions have been observed to increase in viscosity when stored for extended periods of time. There is. Additives that are effective in controlling this increase in viscosity have been functionalized by reaction with mono- or di-carboxylic acids or anhydrides used in the production of ashless dispersants as disclosed above. Contains long chain hydrocarbons. In another preferred embodiment, the lubricating oil composition of the present invention comprises an effective amount of a long chain hydrocarbon functionalized by reaction with a mono- or di-carboxylic acid or anhydrate.
When the lubricating composition comprises one or more of the above-mentioned additives, each additive is typically blended into the base oil in an amount that the additive can provide its desired function. Lubrication. Typical effective amounts of such additives when used in crankcase lubricants are listed below. All listed values (except cleaning agent values) are stated as Active Ingredients (AI) in% by weight. As used herein, AI means an additive substance that is not a diluent or solvent.

Although not required, one or more additive concentrates containing additives (concentrates are often referred to as additive packages) are prepared, whereby several additives are added to the oil at the same time. Therefore, it may be desirable to be able to form the above-mentioned lubricating oil composition.
The final composition may be 5-25% by weight, preferably 5-22% by weight, typically 10-20% by weight, with the balance being an oil with a lubricating viscosity. Is.
Preferably, the volatility of Noack according to the above-mentioned fully-blended lubricating oil composition (oil having lubricating viscosity + all additives) is 20% by mass or less, for example 15% by mass or less, preferably 15% by mass or less. It will be 13% by mass or less.
The lubricating oil composition useful in carrying out the present invention can have an overall sulfate ash content of 0.3 to 1.2% by mass, for example 0.4 to 1.1% by mass, preferably 0.5 to 1.0% by mass.

The present invention will be further understood by reference to the following examples. In the examples, all parts are parts by mass unless otherwise specified, and these examples include preferred embodiments of the present invention.
Description of Examples
Although the invention is described and exemplified with reference to particular embodiments, one of ordinary skill in the art will appreciate that the invention is also suitable for many different variations not specifically described herein. Will. Only as an example, certain possible variants will now be explained.
The amount of additive given is the amount of additive containing diluting oil, unless otherwise specified.

1：このホウ酸化分散剤は、インフィニアムUK社(Infineum UK Limited)から入手し得るホウ酸化ポリイソブテニルサクシンイミド分散剤であった。
2：このマグネシウム洗浄剤は、インフィニアムUK社から入手し得る、全塩基価342を持つマグネシウムサリチレート洗浄剤であった。
3：このカルシウム洗浄剤は各オイルについて同一であり、またインフィニアムUK社から入手し得る、225という全塩基価を持つカルシウムサリチレート洗浄剤と、インフィニアムUK社から入手し得る、64という全塩基価を持つカルシウムサリチレート洗浄剤との混合物を含んでいた。
4：このモリブデンジチオカルバメートは、インフィニアムUK社から入手し得るトリマー系モリブデンジチオカルバメートである。
5：この添加剤パッケージは、各オイルについて同一であり、またホウ酸化されていない分散剤、亜鉛ジアルキルジチオホスフェート、アミン系酸化防止剤およびケイ素系消泡剤(silicon antifoam)を含んでいた。
6：この流動点降下剤は、インフィニアムUK社から入手し得るインフィニアム(Infineum) V385であった。
7：この粘度調整剤は、インフィニアムUK社から入手し得るインフィニアム(Infineum) SV603であった。
8：このベースストックは、APIグループ(Group) IIIベースオイルを含んでいた。 Example 1
Two SAE 0W-20 grade lubricant compositions have been produced that represent the motor oils of typical European mid-SAPS passenger cars. The formulations of these compositions are shown in Table 2 below.

1: This booxide dispersant was a polyisobutenyl succinimide dispersant booxide available from Infineum UK Limited.
2: This magnesium cleaning agent was a magnesium salicylate cleaning agent having a total base value of 342, which was available from Infinium UK.
3: This calcium cleaner is the same for each oil and is available from Infinium UK, a calcium salicylate cleaner with a total base value of 225, and is available from Infinium UK, 64. It contained a mixture with a calcium salicylate detergent having a total base value.
4: This molybdenum dithiocarbamate is a trimmer molybdenum dithiocarbamate available from Infinium UK.
5: This additive package was the same for each oil and contained an unoxidized dispersant, zinc dialkyldithiophosphate, an amine-based antioxidant and a silicon-based antifoam.
6: This pour point depressant was Infineum V385, available from Infinium UK.
7: This viscosity modifier was Infineum SV603 available from Infinium UK.
8: This basestock contained API Group III base oil.

Comparative Oil 1 contains a typical amount of booxide dispersant, the oil composition having a boron content of 57 ppm and no molybdenum-containing additives. The oil (Oil) 2 of the embodiment of the present invention contains a larger amount of booxide dispersant, the oil composition thereof has a boron content of 195 ppm, and the molybdenum-containing compound is the oil. The composition is given 198 ppm molybdenum.

The above oils were tested for the incidence of LSPI events according to the GM LSPI test for approval application for the Dexos ^TM standard, and the results are shown in Table 3 below. The test limit for the above dextests for 5 experiments is 0 0 0 2 2, which results in zero LSPI events in experiments 1, 2 and 3 and less than or equal to 2 in experiments 4 and 5. Compositions that result in LSPI events pass this test, while with more than zero LSPI events in Experiments 1, 2 and / or 3 and / or compositions with more than 2 LSPI events in Experiments 4 and 5. Means fail this test.

Over all five experiments with each composition, Oil 2 showed a lower frequency of LSPI events and passed the Dexos ^TM test above, while Oil 1 failed the Dexos test. .. These results indicate that combined increases in both boron and molybdenum content provide a decrease in the frequency of LSPI events.

9：このホウ酸化分散剤は、インフィニアムUK社(Infineum UK Limited)から入手し得るホウ酸化ポリイソブテニルサクシンイミド分散剤であった。
10：このカルシウム洗浄剤は、インフィニアムUK社から入手し得る、全塩基価225を持つカルシウムサリチレート洗浄剤を含んでいた。
11：このモリブデンジチオカルバメートは、インフィニアムUK社から入手し得る、トリマー系モリブデンジチオカルバメートである。
12：この添加剤パッケージは各オイルについて同一であり、またホウ酸化されていない分散剤、亜鉛ジアルキルジチオホスフェート、アミン系酸化防止剤、ヒンダードフェノール酸化防止剤、無灰摩擦調整剤およびケイ素系消泡剤を含んでいた。
13：この流動点降下剤は、インフィニアムUK社から入手し得るインフィニアム(Infineum) V385であった。
14：この粘度調整剤は、インフィニアムUK社から入手し得るインフィニアム(Infineum) SV603であった。
15：このベースストックは、GTLベースオイルを含んでいた。 Example 2
Two additional SAE OW-20 grade lubricant compositions have been produced that correspond to the motor oils of typical European mid-SAPS passenger cars with a phosphorus content of 0.09% by weight. The composition table of these compositions is shown in Table 4 below.

9: This booxide dispersant was a polyisobutenyl succinimide dispersant booxide available from Infineum UK Limited.
10: This calcium cleaner contained a calcium salicylate cleaner with a total base value of 225, available from Infinium UK.
11: This molybdenum dithiocarbamate is a trimmer molybdenum dithiocarbamate available from Infinium UK.
12: This additive package is the same for each oil and is not booxidized dispersant, zinc dialkyldithiophosphate, amine-based antioxidants, hindered phenolic antioxidants, ashless friction modifiers and silicon-based defoamers. It contained a foaming agent.
13: This pour point depressant was Infineum V385, available from Infinium UK.
14: This viscosity modifier was Infineum SV603 available from Infinium UK.
15: This basestock contained GTL base oil.

From Table 4, it can be seen that Oil 3 has a lower boron content and a lower molybdenum content compared to the Oil 4 composition.
These compositions were tested for the incidence of LSPI events according to the ASTM (Ford) LSPI test for application for GF-6 / API SP, and the results are shown in Table 6 below.

Over all four experiments with each composition, Oil 4 showed a significantly lower frequency of LSPI events compared to Oil 3, which was both boron and molybdenum content. It is shown that the increase in is resulting in a decrease in the frequency of LSPI events.

16：このホウ酸化分散剤は、インフィニアムUK社(Infineum UK Limited)から入手し得るホウ酸化ポリイソブテニルサクシンイミド分散剤であった。
17：この非-ホウ酸化分散剤は、インフィニアムUK社から入手し得るポリイソブチレンサクシンイミド分散剤であった。この非-ホウ酸化分散剤の量は、上記オイル内に存在するホウ素の量を変えるために用いられたホウ素化分散剤の変動する量と、釣り合わせるために変動する。
18：このカルシウム洗浄剤は、インフィニアムUK社から入手し得る、全塩基価300を持つカルシウムスルホネート洗浄剤を含んでいた。
19：このマグネシウム洗浄剤は、インフィニアムUK社から入手し得る、全塩基価400を持つマグネシウムスルホネート洗浄剤であった。
20：このモリブデンジチオカルバメートは、インフィニアムUK社から入手し得るトリマー型のモリブデンジチオカルバメートである。
21：この添加剤パッケージは各オイルについて同一であり、また亜鉛ジアルキルジチオホスフェート、アミン系酸化防止剤、ヒンダードフェノール酸化防止剤、無灰摩擦調整剤、希釈オイルおよびケイ素系消泡剤を含んでいた。
22：この流動点降下剤は、インフィニアムUK社から入手し得るインフィニアム(Infineum) V387であった。
23：この粘度調整剤は、シェブロンオロナイト(Chevron Oronite)から入手し得るパラトン(Paratone) 68530であった。
24：このベースストックは、APIグループ(Group) IIベースストックを含んでいた。 Example 3
Produced five 5W-30 grade lubricants, equivalent to the motor oils of typical European mid-SAPS passenger cars. The formulation table for these compositions is shown in Table 6 below.

16: This booxide dispersant was a polyisobutenyl succinimide dispersant booxide available from Infineum UK Limited.
17: This non-boroxidation dispersant was a polyisobutylene succinimide dispersant available from Infinium UK. The amount of this non-boronizing dispersant varies to balance with the varying amount of the boring dispersant used to alter the amount of boron present in the oil.
18: This calcium cleaner contained a calcium sulfonate cleaner with a total base value of 300, available from Infinium UK.
19: This magnesium cleaning agent was a magnesium sulfonate cleaning agent having a total base value of 400, which was available from Infinium UK.
20: This molybdenum dithiocarbamate is a trimmer type molybdenum dithiocarbamate available from Infinium UK.
21: This additive package is the same for each oil and also contains zinc dialkyldithiophosphates, amine-based antioxidants, hindered phenolic antioxidants, ashless friction modifiers, diluted oils and silicon-based defoamers. board.
22: This pour point depressant was Infineum V387 available from Infinium UK.
23: This viscosity modifier was Paratone 68530 available from Chevron Oronite.
24: This basestock included the API Group II basestock.

Oils 5 and 6 are completely boron-free (boron-free dispersants are included in these compositions to maintain the functionality of the equivalent dispersants in the above compositions). Oils 5 and 7 are completely molybdenum free. Thus, oil 5 contains neither boron nor molybdenum, oil 6 contains a relatively large amount of molybdenum but no boron at all, and oil 7 contains a relatively large amount of boron. Contains no molybdenum. Oils 8 and 9 contain boron and molybdenum. Oil 8 contains a relatively large amount of boron and a relatively large amount of molybdenum, which are the same as oils 7 and 6, respectively, and oil 9 contains half the amount of boron and molybdenum.

These compositions were tested for the incidence of LSPI events according to the ASTM (Ford) LSPI test for application for GF-6 / API SP, and the results are shown in Table 7 below. These tests were performed in a random order in matrix fashion, with 5 control oil experiments each.

The above LSPI test results presented in Table 7 are also shown in the matrix format in FIG. These test results show no reduction in LSPI frequency from 0 ppm to 400 ppm in the absence of molybdenum, due to a substantial increase in the boron content of the above composition, and from 0 ppm to 700 ppm in the absence of boron. By substantially increasing the molybdenum content of the composition up to, a modest reduction (43% reduction) in LSPI frequency is exhibited. In contrast, the test results show a significant, even more substantial reduction (57% reduction) in LSPI frequency, from 0 ppm to 200 ppm and 350 ppm, respectively, simply by moderately increasing both the boron content and the molybdenum content. ) Is shown. Moreover, the test results show a further significant reduction (71% reduction) in LSPI frequency by substantially increasing both the boron content and the molybdenum content from 0 ppm to 400 ppm and 700 ppm, respectively. Unexpectedly, the test results of Example 3 show a synergistic effect on the reduction in LSPI frequency resulting from the combination of both boron and molybdenum in the lubricating oil composition.
Where integers or elements are mentioned in the above description, including known, obvious or predictable equivalents, such equivalents are incorporated herein as if they were described individually. To determine the true scope of the invention, the claims should be referred to and the claims should be construed to include any such equivalent. Similarly, the integers or features of the invention described to the reader as preferred, advantageous, convenient, etc. are optional and do not limit the scope of the independent claims of the invention. Will be understood. Moreover, such arbitrary integers or features may be a possible benefit in some embodiments of the invention, but may be undesirable and therefore may not exist in other embodiments. Should be understood.

Claims (20)

A method of reducing low speed ligation (LSPI) events in a direct eruption spark ignition internal combustion engine, comprising the step of lubricating the crankcase of the engine with a lubricating oil composition, wherein the lubricating oil composition is the lubricating oil composition. The lubricating oil composition comprises a calcium detergent, a boron-containing additive and a molybdenum-containing additive that impart a calcium content of 0.18 to 0.5% by mass based on the mass of the substance to the lubricating oil composition. The lubricating oil has a molybdenum content of 150 to 1,500 mass ppm based on the mass of the lubricating oil composition, and has a boron content of 150 to 1,500 mass ppm based on the mass of the lubricating oil composition. The lubricating oil composition has a magnesium content of 0.03% by mass or less based on the mass of the composition, and has a phosphorus content of 0.01 to 0.12% by mass based on the mass of the lubricating oil composition. The above method, which has a sulfated ash content of 0.3 to 1.2% by mass based on the mass. The method according to claim 1, wherein during operation, the engine generates a brake mean pressure level exceeding 1,500 kPa at an engine speed of 1,000 to 2,500 rpm (rpm) . The method according to claim 1 or 2, wherein the lubricating oil composition has a molybdenum content of 300 to 1,500 mass pp m based on the mass of the lubricating oil composition. The method according to claim 1, 2 or 3, wherein the lubricating oil composition has a boron content of 200 to 1,000 mass ppm based on the lubricating oil composition. The method according to any one of claims 1 to 4, wherein the calcium detergent imparts a calcium content of 0.18 to 0.4% by mass to the lubricating oil composition based on the mass of the lubricating oil composition. The method according to any one of claims 1 to 5, wherein the lubricating oil composition has a magnesium content of 0.0% by mass based on the mass of the lubricating oil composition. The boron-containing additive is a booxide dispersant, a booxide dispersant viscosity index improver, an alkali metal or alkaline earth metal borate, a booxidized and overbasified metal cleaning agent, booxide epoxiside, hoof. The method according to any one of claims 1 to 6, wherein the method is one or more of an acid ester, a sulfide borate ester, or a borate amide. The method according to any one of claims 1 to 7, wherein the molybdenum-containing additive is an oil-soluble or oil-dispersible organic molybdenum compound. The method according to any one of claims 1 to 8, wherein the lubricating oil composition has a phosphorus content of 0.08% by mass or less based on the mass of the lubricating oil composition. Use of a combination of boron-containing and molybdenum-containing additives in the lubricating oil composition to reduce LSPI events when the lubricating oil composition lubricates the crankcase of a direct injection-spark ignition internal combustion engine. The molybdenum-containing additive imparts a molybdenum content of at least 150 mass ppm based on the mass of the lubricating oil composition to the lubricating oil composition, and the boron-containing additive provides the lubrication. A boron content of at least 150 mass ppm based on the mass of the oil composition is given to the lubricating oil composition, and the lubricating oil composition is 0.18 to 0.5 mass% calcium based on the mass of the lubricating oil composition. The use comprising a calcium detergent which imparts a content to the lubricating oil composition. The use according to claim 10, wherein during operation, the engine produces mean brake pressure levels in excess of 1,500 kPa at engine speeds of 1,000 to 2,500 rpm. The use according to claim 10 or 11, wherein the molybdenum-containing additive imparts a molybdenum content of 150 mass ppm to 1,500 mass pp m based on the mass of the lubricating oil composition to the lubricating oil composition. The use according to any one of claims 10 to 12, wherein the boron-containing additive imparts a boron content of 150 to 1,500 mass pp m relative to the mass of the lubricating oil composition. The use according to any one of claims 10 to 13, wherein the calcium detergent imparts a calcium content of 0.18 to 0.4% by mass based on the mass of the lubricating oil composition to the lubricating oil composition. The use according to any one of claims 10 to 14, wherein the lubricating oil composition has a magnesium content of 0.12% by mass or less. The use according to claim 15, wherein the lubricating oil composition has a magnesium content of 0.0% by mass based on the mass of the lubricating oil composition. The boron-containing additive is a booxide dispersant, booxide dispersant VI improver, alkali metal or mixed alkali metal or alkaline earth metal borate, booxidized and overbasified metal cleaning agent, booxide. The use according to any one of claims 10 to 16, which is one or more of epoxiside, borate ester, sulfurized borate ester, or borate amide. The use according to any one of claims 10 to 17, wherein the molybdenum-containing additive is an oil-soluble or oil-dispersible organic molybdenum compound. The use according to any one of claims 10 to 18, wherein the lubricating oil composition has a phosphorus content of 0.12% by mass or less based on the mass of the lubricating oil composition. The use according to any one of claims 10 to 19, wherein the lubricating oil composition has a sulfated ash content of 0.3 to 1.2% by mass based on the mass of the lubricating oil composition.

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