JP2007063560A - Anti-wear additive composition for low sulfur, low sulfate ash and low phosphorus lubricant composition for high-load diesel engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low sulfur, low sulfate ash and low phosphorus lubricant composition giving good anti-wear performance. <P>SOLUTION: The low sulfur, low sulfate ash and low phosphorus lubricant composition for a low emission gas high-load diesel engine is provided by containing the following ingredients. That is, an anti-wear additive composition comprising (a) a major amount of lubricating viscosity oil and (b) ≥2 mass% metal salt of Mannich condensate based on the total mass weight of the lubricant is provided. And, a low sulfur, low sulfate ash and low phosphorus lubricant condensate is provided by containing the following ingredients. That is, an anti-wear additive composition comprising (a) a lubricating viscosity oil and (b) ≥2 mass% metal salt of Mannich condensate based on the total mass weight of the lubricant is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention particularly relates to a low sulfur, low sulfated ash and low phosphorus lubricating oil composition for a low exhaust high load diesel engine comprising the following components: (a) a major amount of oil of lubricating viscosity, and (b) ) A wear-resistant additive composition comprising at least 2% by weight of a metal salt of a Mannich condensation product based on the total weight of the lubricating oil. The present invention also relates to a low sulfur, low sulfated ash and low phosphorus lubricating oil concentrate comprising the following components: (a) an oil of lubricating viscosity, and (b) at least 2 mass based on the total mass of the lubricating oil. % Wear-resistant additive composition comprising a metal salt of a Mannich condensation product.

  High-load (heavy duty) diesel internal combustion engines mounted on automobiles, construction machinery, and generators are generally operated using light oil or heavy oil (with a sulfur content of approximately 0.05% by mass or more). . Most diesel engine lubricants have a sulfur content of approximately 0.3 to 0.7% by weight, a sulfated ash content of approximately 1.3 to 2.0% by weight, and a phosphorus content of approximately 0.1 to 0.13% by weight. %.

  In order to reduce air pollution, vehicle manufacturers and oil companies are interested in developing lubricating oil systems with low emissions and good fuel economy for high load diesel engines. Environmental pollution caused by exhaust gas from diesel engines includes fine particles, carbon oxides, sulfur oxides, and nitrogen oxides. Diesel engine manufacturers are beginning to install diesel engines with exhaust gas aftertreatment devices including particulate removal devices, oxidation catalysts and reduction catalysts to eliminate environmental problems.

  Both the fuel and the lubricant used to lubricate the diesel engine give the particulates and oxides found in the exhaust from the diesel engine. Conventional anti-wear additives and antioxidants such as zinc dialkyldithiophosphates contribute to reducing the activity of the oxidation catalyst. Therefore, the reduction of the phosphorus content reduces the deactivation of the catalyst used in the exhaust gas aftertreatment device. The zinc dialkyldithiophosphate zinc can also give sulfated ash, which can clog the particulate remover. Therefore, it is necessary to reduce the phosphorus content and zinc content of the lubricating oil in order to protect the oxidation catalyst from degradation and prevent clogging of the particulate removal device.

  Another important concern is sulfated ash derived from alkali and alkaline earth metal detergents in lubricating oils. The non-combustible ash deposit in the diesel engine is collected in the groove of the diesel engine exhaust gas particulate removal device. Conventional lubricating oils used in diesel engines have a high sulfur content and are derived from additive components and base oils. Sulfur in the diesel fuel is converted into sulfuric acid and sulfate, which are transferred to the exhaust gas purifier and become fine particles, which clog the removal device of a high-load diesel engine vehicle equipped with the fine particle removal device. Sulfuric acid can contribute to clogging of the particulate removal apparatus indirectly by wetting the particulates and thereby increasing their mass. Sulfuric acid and sulfate also harm the oxidation catalyst in the exhaust gas cleaning device, which also results in failure to meet the exhaust gas requirements. Therefore, in order for these particulate collection devices and oxidation catalysts to continue to function, it is indispensable to significantly reduce the sulfur content and sulfated ash content of the lubricating oil compared to conventional diesel engine lubricating oil.

  Numerous patents and patent applications describe particulate emissions reduction methods and low sulfur, low sulfated ash and low phosphorus lubricating oil compositions, but consisting of Mannich condensation products that also provide cleanliness There is no disclosure of a low sulfur, low sulfated ash and low phosphorus lubricating oil composition for a low emission diesel engine comprising a reactive additive composition.

  Patent Document 1 discloses a low-sulfuric ash and low-viscosity reaction product obtained by neutralizing a sulfurized alkylphenol mixed with a Mannich base reacted with carbon dioxide with an alkaline earth metal oxide or hydroxide. A lubricating oil composition is disclosed.

  Patent Document 2 discloses an excess of a minor amount of trialkanolamine and zinc dihydrophosphate dithiophosphate that reduces the weight loss of bearings of an internal combustion engine while maintaining low ash content and rust prevention properties. A lubricating oil composition comprising a basic alkaline earth metal compound is disclosed.

  Patent Document 3 discloses a low ash and low phosphorus motor oil with improved oxidation stability as a result of the addition of synergistic amounts of dialkyldiphenylamine antioxidant and sulfurized polyolefin. The synergy between the two additives compensates for the loss of phosphorus in the form of zinc dithiophosphate to the extent that the oil retains SE grade quality.

  Patent Document 4 includes a base oil, an ashless dispersant containing at least about 2% by mass of nitrogen or ester, an oil-soluble antioxidant substance, and an oil-soluble dihydrocarbon dithiophosphate ester antiwear substance, and has a total sulfate ash level Is a low-sulfur ash lubricating oil composition having a mass ratio of 0.01 to 0.6% by mass and a mass ratio of total sulfated ash to dispersant of 0.01: 1 to 0.2: 2. .

  Patent Document 5 discloses a lubricating oil composition and concentrate containing the following components: an overbased alkali metal salt of a carboxylic acid, and an overbased magnesium salt of an acidic compound having a metal ratio of at least 3. However, there is a condition that the lubricating oil composition does not contain an overbased calcium salt of an acidic compound having a metal ratio greater than 3, or the lubricating oil composition does not contain an overbased magnesium salt having a metal ratio greater than 3. Stick.

  Patent Document 6 discloses a lubricating oil composition for an internal combustion engine having a high-temperature shear viscosity of 2.1 to 2.9 mPas, comprising (1) zinc dialkyldithiophosphate, (2) calcium alkyl salicylate and calcium alkyl, and A lubricating base oil is disclosed that includes a metallic detergent selected from a mixture of magnesium alkyl salicylates, and optionally (3) a friction modifier. This lubricating oil composition overcomes the problems of scuffing and wear resistance of moving parts under severe lubricating conditions.

  Patent Document 7 discloses a diesel engine oil composition comprising a lubricating oil base material and one or more metal detergents selected from overbased alkaline earth metal sulfonates, phenolates and salicylates. The total phosphorus content of this composition is limited to 100 parts by weight per million or less, thereby providing a diesel engine oil composition that exhibits oxidation stability and wear resistance.

  Patent Document 8 discloses an unsulfurized alkali-free metal having about 40% to 60% alkylphenol, 10% to 40% alkaline earth alkylphenol, and 20% to 40% alkaline earth monoaromatic alkyl salicylate. A detergent-dispersant composition is disclosed. The composition may have an alkaline earth diaromatic salicylate as long as the molar ratio of monocyclic alkyl salicylate to diaromatic alkyl salicylate is at least 8: 1.

  US Pat. No. 6,057,049 is a marine diesel lubricant composition having a TBN of at least 10 and preferably a VI of at least 90, comprising a major amount of oil of lubricating viscosity and a small amount of ashless wear resistance mixed therewith. And (i) an overbased metal detergent comprising a surfactant system derived from at least two surfactants with a TBN of at least 300, more preferably at least 400, and / or (i) ii) Lubricant compositions comprising in the form of metal detergents other than (i) (provided that the detergent (ii) is present, the composition is a minor amount up to 5.0% by weight, based on the total weight of the composition. In the absence of extreme pressure additives).

Patent Document 10 and Patent Document 11 describe (a) a synthetic base oil composition having a total kinematic viscosity of at least about 4.8 × 10 ⁻⁶ m ² / s (4.8 cSt) at 100 ° C. and a viscosity index of at least 110. , (B) a distributed viscosity modifier, and (c) a sulfur-free functionalized hydrocarbon-substituted phenol detergent can provide improved load on valve train wear along with long drain spacing in high load diesel engines. It is disclosed.

  Patent Document 12 discloses a lubricating oil composition suitably used for a diesel engine that emits a large amount of sulfur dioxide. The composition exhibits corrosion / antiwear properties against sulfur dioxide. The lubricating oil composition is a component that is a compound selected from the group consisting of a lubricating base oil, an overbased alkaline earth metal sulfonate, an overbased alkaline earth metal phenate, and an overbased alkaline earth metal salicylate (A) and the component (B) which is a bis type | mold succinimide compound are included.

  Patent Document 13 discloses a lubricating oil for internal combustion engines that can be used in combination with a fuel having 350 parts per million or less of sulfur, in particular, a lubricant base oil, a boron-containing ashless dispersant, a molybdenum-containing lubricant, and a metal type cleaner. Agent and zinc dithiophosphate are disclosed.

  Patent Document 14 discloses a detergent composition containing one or more metal detergents composed of a metal salt of an organic acid, which is 50 mol% or more based on the molar amount of the metal salt of an organic acid in the detergent composition. And (I) a metal salt of an aromatic carboxylic acid, or (II) a metal salt of a phenol, or (III) both a metal salt of an aromatic carboxylic acid and a metal salt of a phenol, and the amount of phosphorus in the oil composition And a sulfur amount of 0.09% by weight or less and a maximum of 0.5% by weight based on the weight of the oil composition, respectively, in a small amount to improve the oxidation resistance of the lubricating oil composition. It is disclosed for use in lubricating oil compositions. It has also been found that a detergent composition comprising 50 mol% or more of a metal salt of an aromatic carboxylic acid improves the reduction of wear in the engine.

  Patent Documents 15 and 16 disclose lubricating oil compositions containing the following components: (A) a major amount of oil of lubricating viscosity, and added thereto: (B) metal salt of organic acid A detergent composition comprising one or more metal detergents comprising a metal salt of an aromatic carboxylic acid of 50 mol% or more based on the molar amount of the metal salt of an organic acid in the detergent composition A small amount of the composition, and (C) a small amount of one or more auxiliary additives; provided that the total phosphorus amount and the total sulfur amount derived from (B) or (C) or both (B) and (C) Based on the mass of the product, phosphorus is 0.1% by mass or less, and sulfur is 0.5% by mass at maximum. It has been found that this detergent composition comprising 50 mol% or more of a metal salt of an aromatic carboxylic acid improves the reduction of wear in the engine.

  Patent Document 17 discloses a lubricating oil composition that can be used in combination with a low-sulfur fuel oil, preferably a base oil, alkenyl, alkyl succinimide or derivative thereof having a maximum sulfur content of 0.2% by mass. An ash dispersant, a metal-containing detergent containing an organic acid metal salt, a zinc dialkyldithiophosphate, a zinc dialkylaryldithiophosphate, and an antioxidant selected from the group consisting of a phenol compound, an amine compound and a molybdenum-containing compound, and a dialkyl It is disclosed that the ratio of the phosphorus content of zinc dithiophosphate to the zinc content of zinc dialkylaryl dithiophosphate is in the range of 20: 1 to 2: 1.

  Patent Document 18 discloses that a low sulfur content lubricating oil is used in combination with a low sulfur fuel to reduce particulate emissions of a diesel engine equipped with a particulate collection device.

Specification of Canadian Patent No. 810120 U.S. Pat. No. 4,089,791 U.S. Pat. No. 4,304,420 US Pat. No. 5,102,566 US Pat. No. 5,490,945 US Pat. No. 6,141,288 US Pat. No. 6,159,911 US Pat. No. 6,162,770 US Pat. No. 6,277,794 US Pat. No. 6,331,510 US Pat. No. 6,610,637 US Pat. No. 6,376,434 US Pat. No. 6,730,638 US Pat. No. 6,784,143 European Patent Application No. 012017752.1 (Publication No. EP1256619A1) Specification, withdrawn as of March 5, 2005 US Patent Application No. 10 / 142,513 (Publication No. US2003 / 0096716A1) Specification US Patent Application No. 10/430594 (Publication No. US2003 / 0216266A1) Specification International Publication No. WO2004 / 046283A1 Pamphlet

  The present invention relates to a low sulfur, low sulfated ash and low phosphorus lubricating oil composition, and a low sulfur, low sulfated ash and low phosphorus lubricating oil concentrate for low emission, high load diesel engines.

The present invention relates to a low sulfur, low sulfated ash and low phosphorus lubricating oil composition for a low exhaust gas high load diesel engine comprising: (a) a major amount of oil of lubricating viscosity; and (b) a lubricating oil. An antiwear additive composition comprising at least 2% by weight of a metal salt of a Mannich condensation product based on the total weight of The present invention also relates to a low sulfur, low sulfated ash and low phosphorus lubricating oil concentrate comprising the following components: (a) an oil of lubricating viscosity, and (b) at least 2 mass based on the total mass of the lubricating oil. % Wear-resistant additive composition comprising a metal salt of a Mannich condensation product.
The lubricating oil composition of the present invention can also be used as a lubricating oil for gasoline engines.

  The Mannich condensation product used in the antiwear additive composition of the present invention surprisingly exhibits antiwear performance while maintaining good cleanliness.

That is, the present invention relates to a low sulfur, low sulfated ash and low phosphorus lubricating oil composition for a low exhaust gas high load diesel engine comprising the following components:
A wear-resistant additive composition comprising (a) a major amount of an oil of lubricating viscosity, and (b) at least 2% by weight of a metal salt of a Mannich condensation product, based on the total weight of the lubricating oil composition.

  In the lubricating oil composition of the present invention, the concentration of the Mannich condensation product is preferably about 2% by mass to about 12% by mass based on the total mass of the lubricating oil composition. More preferably, the concentration of the Mannich condensation product is from about 3% to about 9% by weight based on the total weight of the lubricating oil composition, and most preferably the concentration of the Mannich condensation product is based on the total weight of the lubricating oil composition. About 4 mass% to about 7 mass%.

  The Mannich condensation product (b) in the lubricant antiwear additive composition of the present invention comprises formaldehyde or an aldehyde having 1 to about 10 carbon atoms and ammonia, a lower alkylamine, a polyamine and a mixture thereof. Manufactured from selected nitrogen bases and alkylphenols.

  The alkyl group of the alkylphenol used to produce the Mannich condensation product of the antiwear additive composition (b) is a linear or branched alkyl group. Preferably, the alkyl group of the alkylphenol used to prepare the Mannich condensation product is a branched alkyl group.

  The branched chain alkyl group of the alkylphenol used to produce the Mannich condensation product of the antiwear additive composition (b) preferably has from about 4 carbon atoms to about 60 carbon atoms. More preferably, the alkyl group of the alkylphenol has from about 6 carbon atoms to about 40 carbon atoms. Most preferably, the alkyl group of the alkylphenol has from about 8 carbon atoms to about 20 carbon atoms.

  Aldehydes that can be used for the production of Mannich condensation products are aldehydes having 1 to about 10 carbon atoms. Preferably, the aldehyde is formaldehyde, more preferably paraformaldehyde.

  The nitrogen base is selected from ammonia, a lower alkyl amine having 1 to about 10 carbon atoms in the alkyl group, and a polyamine having 2 to about 12 amine nitrogen atoms and 2 to about 40 carbon atoms.

  The nitrogen base compound for the production of the Mannich condensation product is preferably a lower alkylamine having 1 to about 10 carbon atoms in the alkyl group. Lower alkylamines are alkyl mono-amines such as mono-methylamine, mono-ethylamine, mono-propylamine, mono-butylamine and mono-pentylamine. More preferably, the alkyl mono-amine is mono-methylamine.

  Examples of polyamines that can be used in the production of Mannich condensation products include mono-alkylene polyamines and polyalkylene polyamines.

  In a preferred embodiment of the lubricating oil composition of the present invention, the Mannich condensation product of the antiwear additive composition (b) is an alkylphenol, provided that the alkyl group of the alkylphenol has from about 8 carbon atoms to about 20 carbon atoms. It is made from a branched alkyl group, paraformaldehyde and mono-methylamine.

  The metal of the metal salt of the Mannich condensation product may be an alkali metal or an alkaline earth metal. Preferably the metal is an alkaline earth metal, more preferably the alkaline earth metal is calcium.

  The sulfur content of the lubricating oil composition of the present invention is preferably in the range of 0.0 weight percent to about 0.4 weight percent based on the total weight of the lubricating oil. More preferably, the sulfur content of the lubricating oil composition of the present invention is in the range of 0.05 weight percent to about 0.3 weight percent based on the total weight of the lubricating oil. Most preferably, the sulfur content of the lubricating oil composition of the present invention is in the range of 0.1 weight percent to about 0.2 weight percent based on the total weight of the lubricating oil.

  The sulfated ash content of the lubricating oil composition of the present invention is preferably in the range of 0.2 wt% to about 4.0 wt% based on the total weight of the lubricating oil. More preferably, the sulfated ash content of the lubricating oil composition of the present invention is in the range of 0.3% to about 2.0% by weight based on the total weight of the lubricating oil. Most preferably, the sulfated ash content of the lubricating oil composition of the present invention is in the range of 0.5% to about 1.2% by weight based on the total weight of the lubricating oil.

  The phosphorus content of the lubricating oil composition of the present invention is preferably in the range of 0.005 wt% to about 0.06 wt% based on the total weight of the lubricating oil. More preferably, the phosphorus content of the lubricating oil composition of the present invention is in the range of 0.015 wt% to about 0.05 wt% based on the total weight of the lubricating oil. Most preferably, the phosphorus content of the lubricating oil composition of the present invention is in the range of 0.03% to about 0.04% by weight based on the total weight of the lubricating oil.

  The lubricating oil composition was further selected from detergents, dispersants, antioxidants, viscosity index improvers, corrosion inhibitors, antiwear additives, friction modifiers, pour point depressants and antifoaming agents. Contains one or more lubricating oil additives.

  The lubricating oil composition preferably further contains one or more dispersants. More preferably, the dispersant is an ashless dispersant and the most preferred ashless dispersant is a derivative of succinic anhydride.

  The lubricating oil composition of the present invention may also contain viscosity index improvers such as polyalkyl methacrylates, ethylene-propylene copolymers, styrene-butadiene copolymers and polyisoprene.

  Corrosion inhibitors and antioxidants contemplated for use in the lubricating oils of the present invention are metal dialkyldithiophosphates and diphenylamine derivatives.

  Metal dialkyldithiophosphates may also be included in the lubricating oil composition of the present invention to reduce wear. However, it can be said that it is advantageous to suppress the amount of these additives because the metal provides sulfated ash to the lubricating oil and phosphorus is harmful to the exhaust gas oxidation catalyst. Examples of metal dialkyldithiophosphates include zinc and molybdenum salts of dialkyldithiophosphates.

  Generally, friction modifiers are used to impart proper friction properties to the lubricating oil composition. Friction modifiers that can be used are fatty acid esters and amides, and molybdenum compounds such as amine-molybdenum complexes and molybdenum dithiocarbamates. However, since addition of molybdenum dithiocarbamate further gives sulfur to the lubricating oil composition and sulfate ash to the exhaust gas system, this point needs attention.

  Pour point depressants are those that lower the temperature at which the liquid can flow or can be injected. Additives that optimize the low temperature fluidity of the lubricating oil are various copolymers such as polymethacrylate.

  Antifoaming agents that can be used are of the polysiloxane type.

Low sulfur, low sulfated ash and low phosphorus lubricating oil concentrates for low exhaust high load diesel engines, including:
(A) an oil having a lubricating viscosity of from about 10% to about 90% by weight based on the total weight of the lubricating oil concentrate; and (b) at least 2% by weight of the Mannich condensation product based on the total weight of the lubricating oil concentrate. An antiwear additive composition comprising a metal salt.

A method of lubricating a low emission high load diesel engine comprising lubricating with a low sulfur, low sulfated ash and low phosphorus lubricating oil composition comprising:
A wear-resistant additive composition comprising (a) a major amount of an oil of lubricating viscosity, and (b) at least 2% by weight of a metal salt of a Mannich condensation product, based on the total weight of the lubricating oil composition.

  According to the research of the present inventors, when a low sulfur, low sulfated ash and low phosphorus lubricating oil composition comprising an antiwear additive composition comprising a metal salt of a Mannich condensation product is used in a low exhaust gas high load diesel engine It has been found that it provides good wear control. In conventional lubricating oil compositions, wear inhibition is achieved by the addition of metal salts of dialkyldithiophosphates, such as zinc dialkyldithiophosphate, but the metals in these antiwear additives are the sulfated ash content of the lubricating oil. It contributes to the increase, and phosphorus causes deactivation of the oxidation catalyst used in the exhaust gas aftertreatment device. The antiwear additive composition used in the lubricating oil composition of the present invention provides good wear control without contributing to an increase in sulfur and sulfated ash, and deactivates the oxidation catalyst because it does not contain any phosphorus There is nothing.

[Definition]
The following terms, as used herein, have the following meanings unless otherwise indicated:

  “Alkali metal” as used herein means a Group I metal of the periodic table, such as sodium, potassium and lithium.

  “Alkaline earth metal” as used herein means a Group II metal of the periodic table, such as calcium and magnesium.

  “Detergent” as used herein means an additive designed to keep the acid neutralizing compound in solution in oil. Detergents are usually alkaline and react with strong acids (sulfuric acid and nitric acid) that cause corrosion in engine parts if generated and left unblocked in the course of fuel combustion. Suitable detergents for use in the present invention are alkyl sulfonates, alkyl phenates and Mannich base condensates. A number of detergents are commercially available and readily available.

  “Dispersant” as used herein means an additive that keeps soot and combustion products suspended in an oil-filled engine body, thereby preventing it from depositing as sludge or lacquer. . In general, an ashless dispersant is a nitrogen-containing dispersant formed by the reaction of an alkenyl succinic anhydride and an amine. Examples of such dispersants are alkenyl succinimides and succinamides. These dispersants can be further modified, for example, by reaction with boron or ethylene carbonate. In addition, an ester-based ashless dispersant derived from a long-chain hydrocarbon-substituted carboxylic acid and a hydroxy compound can also be used. Preferred ashless dispersants are those derived from polyisobutenyl succinic anhydride. Dispersibility can also be controlled by a dispersion-type viscosity modifier such as polymethacrylate, alkyl methacrylate styrene copolymer, polyalkyl methacrylate, and olefin copolymer. A number of dispersants are commercially available.

  “Overbased”, as used herein, is an alkaline earth metal alkylphenol, alkyl salicylate, and alkyl sulfonate, wherein the ratio of the number of equivalents of alkaline earth metal to the number of equivalents of organic moiety is greater than 1. Mean big. Low overbasing means alkaline earth metal alkylphenols, alkyl salicylates and alkyl sulfonates having a total base number (TBN) greater than 1 and less than or equal to 20, and medium overbasicity is greater than 20 and less than or equal to 200 Alkaline earth metal alkylphenols, alkyl salicylates and alkyl sulfonates are meant. High overbasing means alkaline earth metal alkylphenols, alkyl salicylates and alkyl sulfonates with a TBN greater than 200.

  “Sulfated ash” as used herein means non-flammable residues resulting from detergents and metallic additives in lubricating oils. ASTM test D874 is used to determine sulfated ash.

  “Total base number” or “TBN” as used herein means the amount of base equivalent to milligrams of KOH in a gram of sample. Therefore, the higher the TBN value, the stronger the alkalinity of the product, which reflects the higher alkalinity. The ASTM D2896 test is used to determine TBN.

  Unless otherwise specified, all percentages are weight percent.

[Lubricating oil composition]
Low sulfur, low sulfated ash and low phosphorus lubricating oil compositions that contain an antiwear additive composition comprising a metal salt of a Mannich condensation product provide good wear control when used in low exhaust gas high load diesel engines. I found it to bring. In conventional lubricating oil compositions, wear inhibition is achieved by the addition of metal salts of dialkyldithiophosphates, such as zinc dialkyldithiophosphate, but the metals in these antiwear additives are the sulfated ash content of the lubricating oil. It contributes to the increase, and phosphorus causes deactivation of the oxidation catalyst used in the exhaust gas aftertreatment device. The antiwear additive composition used in the lubricating oil composition of the present invention provides good wear suppression without contributing to an increase in sulfur and sulfated ash, and also deactivates the oxidation catalyst because it does not contain any phosphorus There is nothing.

  The lubricating oil composition of the present invention can be produced by simply blending or mixing the compounds described in detail below. Also, to facilitate blending of lubricating oil compositions containing the desired concentration of additives, these compounds may be pre-blended as a concentrate or package in a suitable ratio with various other additives. You can also.

(Oil of lubricating viscosity)
As used herein, an oil or base oil of lubricating viscosity means a lubricating oil, which may be a mineral oil or a synthetic oil of lubricating viscosity, but can preferably be used in a crankcase of an internal combustion engine. Is. The viscosity of the crankcase lubricant is typically about 1300 centistokes at -17.8 ° C to 22.7 centistokes at 98.9 ° C. Lubricating oils can be derived from synthetic or natural sources. Mineral oils used as base oils in the present invention can include paraffinic, naphthenic, and other oils commonly used in lubricating oil compositions. Synthetic oils include hydrocarbon synthetic oils and synthetic esters. Synthetic hydrocarbon oils that can be used include alpha olefin liquid polymers having the proper viscosity. Particularly useful are hydrogenated liquid oligomers of C ₆ -C ₁₂ alpha olefins such as 1-decene trimer. Similarly, alkylbenzenes of the proper viscosity, such as didodecylbenzene, may be used. Synthetic esters that can be used include esters of monocarboxylic acids and polycarboxylic acids with monohydroxyalkanols and polyols. Representative examples include didodecyl adipate, pentaerythritol tetracaproate, di-2-ethylhexyl adipate, and dilauryl sebacate. Complex esters synthesized from mixtures of mono and dicarboxylic acids and mono and dihydroxy alkanols can also be used. A blend of hydrocarbon oil and synthetic oil may be used. For example, blends of 10% to 25% by weight of hydrogenated 1-decene trimer with 75% to 90% by weight of 37.8 ° C. mineral oil at 683 centistokes make an excellent lubricating oil base. . A base oil derived from the Fischer-Tropsch process may also be used in the lubricating oil composition of the present invention.

  Furthermore, it is preferable that the oil of lubricating viscosity used for producing the lubricating oil composition of the present invention is a low sulfur base oil. The use of a low sulfur base oil is helpful in obtaining a lubricating oil composition having an extremely low sulfur content. The sulfur content of the base oil is well known to those skilled in the art, and a low sulfur base oil can be appropriately selected for the present invention.

[Abrasion resistance additive]
(Metallic salt of Mannich condensation product)
The Mannich condensation product can be produced using an alkylphenol, an aldehyde, and a nitrogen base compound selected from ammonia, a lower alkylamine, a polyamine, and a mixture thereof.

  The alkyl group of the alkylphenol used to produce the Mannich condensation product of the antiwear additive composition (b) is a linear or branched alkyl group. Preferably, the alkyl group of the alkylphenol used to produce the Mannich condensation product is a branched alkyl group.

  The alkyl group of the alkylphenol used to make the Mannich condensation product may be a branched alkyl group containing from about 4 carbon atoms to about 60 carbon atoms, or from about 6 carbon atoms to carbon atoms. It may be a linear alkyl group containing about 60. Preferably, the alkyl group of the alkylphenol is a branched alkyl group containing from about 8 carbon atoms to about 20 carbon atoms. The alkyl group is preferably bonded to the alkylphenol moiety at the ortho or para position relative to the hydroxyl group.

  More preferably, the ratio of bonds at the ortho and para positions of the alkyl group is 20:80 based on the total alkylphenol, and most preferably the ratio of bonds at the ortho and para positions of the alkyl group is based on the total alkylphenol. 5:95.

  Aldehydes that can be used for the production of Mannich condensation products are aldehydes having 1 to about 10 carbon atoms. Preferably, the aldehyde is formaldehyde, more preferably paraformaldehyde.

  The nitrogen base compound is selected from ammonia, a lower alkylamine having an alkyl group having 1 to 10 carbon atoms, and a polyamine having 2 to about 12 amine nitrogen atoms and 2 to about 40 carbon atoms.

  Preferably, the nitrogen base compound for the production of the Mannich condensation product is a lower alkylamine whose alkyl group has 1 to about 10 carbon atoms. Lower alkylamines are alkyl mono-amines such as mono-methylamine, mono-ethylamine, mono-propylamine, mono-butylamine, and mono-pentylamine. More preferably, the alkyl mono-amine is mono-methylamine.

  Examples of polyamines that can be used in the production of the Mannich condensation product used in the antiwear additive composition of the present invention include mono-alkylene polyamines and polyalkylene polyamines. Examples of mono-alkylene polyamines include ethylene di-amine, ethylene tri-amine and ethylene tetra-amine, propylene di-amine, and propylene tri-amine. Examples of polyalkylene polyamines include di-ethylene di-amine, di- (tri-methylene) tri-amine, di-propylene tri-amine, and tri-ethylene tetra-amine.

  The metal salt of the Mannich condensation product used in the lubricating oil composition of the present invention can be produced by any method known to those skilled in the art. In general, Mannich condensation products are prepared by reacting alkylphenols, formaldehyde and mono-alkylamines with metal hydroxides in the presence of a diluent.

  Mannich condensation products are well known to those skilled in the art. Mannich condensation products can be prepared using alkylphenols, aldehydes and amines by any method known to those skilled in the art. For example, a Mannich condensation product can be produced as described in US Pat. No. 5,370,805.

  The metal salt of the Mannich condensation product can be produced by any well-known method using a metal oxide, metal hydroxide or metal alkoxide. The metal may be an alkali metal or an alkaline earth metal. Preferably the metal is an alkaline earth metal, more preferably the alkaline earth metal is calcium.

[Other additives]
In addition to the antiwear additive composition of the present invention, the lubricating oil composition of the present invention generally also contains other additives used to impart desired properties to the lubricating oil composition of the present invention. It may be. Thus, the lubricating oil contains one or more additives such as dispersants, antioxidants, viscosity index improvers, corrosion inhibitors, antiwear additives, friction modifiers, pour point depressants and antifoaming agents. It may be.

  In order to obtain the best overall results from the standpoint of imparting the desired properties to conventional lubricating oil compositions for heavy duty diesel engine lubricating oils, the lubricating oil should be an anti-wear additive composition of the present invention. The product is included in an amount necessary to provide the desired anti-wear performance, and includes an effective amount of a compatible combination of each of the various additives described above.

(Low, medium and high overbased metal detergents)
A small amount of a low or medium overbased metal detergent may optionally be used in the lubricating oil composition of the present invention. Examples of low and medium overbased metal detergents are low or medium overbased sulfonic acids, salicylic acid, carboxylic acids or phenols, or Mannich condensation products of alkylphenols, aldehydes and amines. These detergents may be alkali metal detergents or alkaline earth metal detergents. An alkaline earth metal detergent is preferable, and a calcium detergent is more preferable. These detergents have a TBN greater than 1 and about 500 or more. However, it is worth noting that further additions of detergents such as those described above can contribute to the sulfur and / or sulfated ash content of the lubricating oil. These detergents are well known in the art and are also commercially available.

(Dispersant)
The lubricating oil composition of the present invention optionally contains an ashless dispersant. In general, an ashless dispersant is a nitrogen-containing dispersant formed by reacting an alkenyl succinic anhydride with an amine. Examples of such dispersants are alkenyl succinimides and alkenyl succinamides. These dispersants can be further modified, for example, by reaction with boron or ethylene carbonate. An ester-based ashless dispersant derived from a long-chain hydrocarbon-substituted carboxylic acid and a hydroxy compound may be used. Preferred ashless dispersants are those derived from polyisobutenyl succinic anhydride. A number of dispersants are commercially available.

(Antioxidant)
Antioxidants are used in lubricating oils to prevent degradation processes that occur naturally in lubricating oils as they age or oxidize in the presence of air. These oxidation processes cause the formation of gums, lacquers and sludges, resulting in increased acidity and viscosity. Examples of antioxidants that can be used include hindered phenols, alkylated and non-alkylated aromatic amines, alkyl or aryl phosphates, esters of thiodicarboxylic acid, carbamic acid or di-thiophosphoric acid salts. Molybdenum compounds such as amine-molybdenum complex compounds and molybdenum dithiocarbamates may also be used as antioxidants. However, care should be taken because the addition of molybdenum dithiocarbamate further adds sulfur and sulfated ash to the lubricating oil composition.

(Viscosity index improver)
Viscosity index improvers are added to lubricating oils to adjust viscosity changes due to temperature changes. Some examples of viscosity index improvers that are commercially available are olefin copolymers, polybutenes, polymethacrylates, vinyl pyrrolidone, and methacrylate copolymers.

(Corrosion inhibitor)
Corrosion inhibitors are included in lubricating oils to protect vulnerable metal surfaces. Such corrosion inhibitors are generally used in very small amounts in the range of about 0.02% to about 1.0% by weight. It is preferred that the corrosion inhibitor should not itself corrode silver and silver-plated bearings, such as di-thiophosphate metal salts. Examples of corrosion inhibitors that can be used include sulfurized olefin corrosion inhibitors and co-sulfurized alkenyl ester / alpha olefin corrosion inhibitors.

  In addition to the substances described above, the lubricating oil composition of the present invention may also contain other additives such as pour point depressants and antifoaming agents. The various additive materials or classes of materials described herein are well known materials and can be easily purchased or produced by known methods or obvious improvements thereof.

  For the anti-wear additive composition used in the low sulfur, low sulfate ash and low phosphorus lubricating oil compositions of the present invention, using formulations prepared as described in Example 1 and Table 1 below. The wear resistance performance was evaluated.

[Example 1]
Comparative formulations A and B and test formulation C contained an ashless dispersant, an antioxidant, a viscosity index improver, a medium overbased alkyl phenate, an anti-wear additive and an antifoam agent. Base oil was used to make each of Comparative Formulations A and B and Test Formulation C 100%. Details of Comparative Formulations A and B and Test Formulation C are given in Table 1 below.

  In each of Comparative Formulations A and B and Test Formulation C, the weight percent concentration of calcium based on the total weight of the lubricating oil was kept constant, as shown in Table 2 below.

  The anti-wear performance of test formulation C comprising the anti-wear additive composition of the present invention comprising a calcium salt of a Mannich condensation product comprises only a mixture of a calcium salt of an alkyl hydroxy aromatic carboxylic acid and a calcium salt of an alkyl phenol. Comparison with comparative formulation A and comparative formulation B with a mixture of calcium salt of alkyl hydroxy aromatic carboxylic acid and calcium salt of alkyl phenol and calcium salt of Mannich condensation product.

Comparative formulation B contains the following ingredients:
(A) Calcium salt of a mixture of the following components:
(A) A mixture of the following components:
(I) an alkyl hydroxybenzene carboxylic acid, provided that the alkyl group of the alkyl hydroxy benzene carboxylic acid was a branched alkyl group containing 12 carbon atoms, and (ii) an alkyl hydroxy benzene carboxylic acid, provided that the alkyl hydroxy benzene The alkyl group of the carboxylic acid was a linear alkyl group containing 20 to 28 carbon atoms, and (b) a mixture of the following components:
(I) a calcium salt of an alkylphenol, provided that the alkyl group of the alkylphenol was a branched alkyl group containing 12 carbon atoms, and (ii) a calcium salt of an alkylphenol, where the alkyl group of the other alkylphenol was carbon. A linear alkyl group containing 20 atoms to 28 carbon atoms,
The calcium salts of (a) and (b) were present in a ratio of 3: 2, and (B) the calcium salt of the Mannich condensation product of alkylphenol, paraformaldehyde and mono-methylamine. The alkyl group of the alkylphenol was a branched alkyl group containing 10 to 20 carbon atoms.

  Comparative formulation A contains only (A) shown in comparative formulation B above. The calcium salts of (a) and (b) were present in a ratio of 3: 2.

  Test formulation C contains only the anti-wear additive composition of the present invention of (B) shown in comparative formulation B above.

Table 1 ────────────────────────────────────
Ingredient composition (mass%)
Comparison A Comparison B Test C
────────────────────────────────────
Base oil 92.08 91.47 90.40
Ashless dispersant 3.4 3.4 3.4
Antioxidant 0.5 0.5 0.5
Viscosity index improver 0.28 0.28 0.28
Medium overbased phenate 0.22 0.22 0.22
Additional anti-wear additive 0.36 0.36 0.36
Antifoam 0.0025 0.0025 0.0025
(A) ^* 3.16 2.01-
(B) ^** -1.76 4.84
────────────────────────────────────
*: (A) is as described above.
**: (B) is as described above.

  Table 2 below shows the amounts of sulfur, sulfated ash, phosphorus and calcium in Comparative Formulations A and B and Test Formulation C.

Table 2 ─────────────────────────────────
Ingredient composition (mass%)
Comparison A Comparison B Test C
────────────────────────────────
Sulfur 0.0992 0.1002 0.1007
Sulfated ash 1.06 1.06 1.06
Phosphorus 0.0378 0.0378 0.0378
Calcium 0.296 0.296 0.296
────────────────────────────────

Example 2 Modified Four-Ball Test Using the modified four-ball test method, the abrasion resistance performance of test formulation C was evaluated in comparison with comparative formulations A and B. Test improvements included pre-aging samples of Formulations AC. Pre-aging was performed to allow the protective film of the wear resistant additive composition of the present invention to be provided and to reveal the effect of oxidative degradation products on the wear resistance performance of the additive. Comparative formulations A and B and test formulation C, approximately 10 milliliter samples were pre-aged at 160 ° C. in the presence of metal spheres for 2 days. The test was started at a load of 10 kilograms, and the load was increased in stages to a total load of 90 kilograms. During the test, the oil temperature, torque and load lever arm displacement at the center of the three fixed spheres were recorded. At the end of the test, the wear index was calculated based on the arm displacement data. The 10th International Colloquium on Tribology-Solving Friction and Wear Problems, Technical Academy (Esslingen, Germany), January 9-11, 1996, for the improvement of this four-ball test. Volume 3, p. It is described in a paper titled “Examination test by an improved four-ball test of an anti-wear additive” by J. Cazin, P. Tequi and Y. Lesieur published in 2063-2073. .

  Data reported were for wear index, oil temperature and torque at the end of the test, and seizure. Table 3 below summarizes the results of the improved four-ball test.

Table 3 ──────────────────────────────────
Improved four-ball test formulation
A B C
──────────────────────────────────
Abrasion index ^* 276 325 30
Temperature (° C) 134 131 113
Torque (Deca Newton) 0.246 0.243 0.159
Seizure Yes Yes No ───────────────────────────────────
*: The wear index was obtained by standardizing the change in measured distance on the sphere surface due to metal loss due to wear in the modified four-ball test. The measured distance was measured in micrometers in the modified four-ball test, but was multiplied by 10 to facilitate reporting of the numerical values obtained in the test.

  The results obtained in the modified four-ball test summarized in Table 3 above show that the test formulation C comprising the antiwear additive composition of the present invention consisting of the calcium salt of the Mannich condensation product is an alkyl hydroxy aromatic carboxylic acid. Rather than Comparative Formulation A comprising only a mixture of calcium salt of acid and calcium salt of alkylphenol, or (i) a mixture of calcium salt of alkyl hydroxy aromatic carboxylic acid and calcium salt of alkylphenol and (ii) calcium of Mannich condensation product It reveals that it gave better wear resistance performance than Comparative Formulation B containing salt. Table 3 above reveals that Formula C performed significantly better than either Comparative Formula A or B for each of the four types of data collected.

  The data shows that Comparative Formulation B did not show wear resistance performance comparable to Test Formulation C, although it contained some of the Mannich condensation product calcium salt as in Test Formulation C. . The presence of a mixture of a calcium salt of an alkyl hydroxy aromatic carboxylic acid and a calcium salt of an alkylphenol in Comparative Formulation B indicates that the Mannich Condensate of an alkylphenol was present even though Comparative Formula B contained a calcium salt of the Mannich Condensate It appears to have a negative impact on anti-wear performance when compared to test formulation C containing only the calcium salt of This result was unpredictable.

Claims (32)

A low sulfur, low sulfated ash and low phosphorus lubricating oil composition for a low exhaust high load diesel engine comprising the following components:
(A) a major amount of oil of lubricating viscosity;
(B) An antiwear additive composition comprising at least 2% by weight of a metal salt of a Mannich condensation product based on the total weight of the lubricating oil composition.   The lubricating oil composition of claim 1, wherein the concentration of the Mannich condensation product ranges from about 2% to about 12% by weight based on the total weight of the lubricating oil composition.   The lubricating oil composition of claim 2, wherein the concentration of the Mannich condensation product ranges from about 3% to about 9% by weight based on the total weight of the lubricating oil composition.   The lubricating oil composition of claim 3, wherein the concentration of the Mannich condensation product is in the range of about 4% to about 7% by weight, based on the total weight of the lubricating oil composition.   In the antiwear additive composition (b), the Mannich condensation product comprises an aldehyde having 1 to about 20 carbon atoms, a nitrogen base compound selected from ammonia, a lower alkylamine, a polyamine, and mixtures thereof; The lubricating oil composition according to claim 1, which is a condensate with an alkylphenol.   The lubricating oil composition according to claim 5, wherein the alkyl group of the alkylphenol of the Mannich condensation product is a linear or branched alkyl group or a mixture thereof.   The lubricating oil composition according to claim 6, wherein the alkyl group of the alkylphenol of the Mannich condensation product is a branched alkyl group.   The lubricating oil composition according to claim 5, wherein the alkyl group of the alkylphenol in the Mannich condensation product has from about 4 carbon atoms to about 60 carbon atoms.   The lubricating oil composition according to claim 8, wherein the alkyl group of the alkylphenol of the Mannich condensation product has from about 6 carbon atoms to about 40 carbon atoms.   The lubricating oil composition according to claim 9, wherein the alkyl group of the alkylphenol of the Mannich condensation product has from about 8 carbon atoms to about 20 carbon atoms.   The alkyl group of the lower alkylamine has from 1 to about 10 carbon atoms and the polyamine has from 2 to 12 amine nitrogen atoms and from 2 to about 40 carbon atoms. 5. The lubricating oil composition according to 5.   12. The lubricating oil composition according to claim 11, wherein the nitrogen base compound for producing the Mannich condensation product is a lower alkyl amine having 1 to about 10 carbon atoms in the alkyl group.   The lubricating oil composition of claim 12, wherein the lower alkyl amine is an alkyl mono-amine.   The lubricating oil composition according to claim 11, wherein the polyamine is a mono-alkylene polyamine, a polyalkylene polyamine, or a mixture thereof.   The lubricating oil composition according to claim 5, wherein the aldehyde used to produce the Mannich condensation product is formaldehyde.   The lubricating oil composition according to claim 5, wherein the aldehyde used to produce the Mannich condensation product is paraformaldehyde.   In the antiwear additive composition (b), the Mannich condensation product is an alkylphenol, provided that the alkyl group of the alkylphenol is a branched alkyl group having from about 8 carbon atoms to about 20 carbon atoms. The lubricating oil composition according to claim 5, wherein the lubricating oil composition is produced from methylamine.   The lubricating oil composition according to claim 1, wherein the metal salt of the Mannich condensation product is an alkali metal or an alkaline earth metal.   The lubricating oil composition according to claim 18, wherein the metal is an alkaline earth metal.   The lubricating oil composition according to claim 19, wherein the alkaline earth metal is calcium.   The lubricating oil composition of claim 1, wherein the sulfur content is in the range of 0.0 weight percent to about 0.4 weight percent based on the total weight of the lubricating oil.   The lubricating oil composition of claim 21, wherein the sulfur content is in the range of 0.05 weight percent to about 0.3 weight percent based on the total weight of the lubricating oil.   The lubricating oil composition of claim 22, wherein the sulfur content is in the range of 0.1 wt% to about 0.2 wt% based on the total weight of the lubricating oil.   The lubricating oil composition of claim 1, wherein the sulfated ash is in the range of 0.2 weight percent to about 4.0 weight percent based on the total weight of the lubricating oil.   The lubricating oil composition of claim 24, wherein the sulfated ash is in the range of 0.3 wt% to about 2.0 wt% based on the total weight of the lubricating oil.   26. The lubricating oil composition of claim 25, wherein the sulfated ash is in the range of 0.5% to about 1.2% by weight based on the total weight of the lubricating oil.   The lubricating oil composition of claim 1, wherein the phosphorus content is in the range of 0.005 wt% to about 0.06 wt% based on the total weight of the lubricating oil.   28. The lubricating oil composition of claim 27, wherein the phosphorus content is in the range of 0.015% to about 0.05% by weight based on the total weight of the lubricating oil.   30. The lubricating oil composition of claim 28, wherein the phosphorus content is in the range of 0.03% to about 0.04% by weight.   The lubricating oil composition further comprises one or more selected from detergents, dispersants, antioxidants, viscosity index improvers, corrosion inhibitors, antiwear additives, friction modifiers, pour point depressants and antifoaming agents. The lubricating oil composition of claim 1 comprising a lubricating oil additive. Low sulfur, low sulfated ash and low phosphorus lubricating oil concentrates for low exhaust high load diesel engines, including:
(A) an oil having a lubricating viscosity of from about 10% to about 90% by weight based on the total weight of the lubricating oil concentrate; and (b) at least 2% by weight of the Mannich condensation product based on the total weight of the lubricating oil concentrate. An antiwear additive composition comprising a metal salt. A method of lubricating a low emission high load diesel engine comprising lubricating with a low sulfur, low sulfated ash and low phosphorus lubricating oil composition comprising:
A wear-resistant additive composition comprising (a) a major amount of an oil of lubricating viscosity, and (b) at least 2% by weight of a metal salt of a Mannich condensation product, based on the total weight of the lubricating oil composition.