Engine oil formulation having improved Sequence VIII performance

Abstract

The present disclosure relates to a method for improving the viscous shear stability of lubricants and lubricant compositions, the lubricant composition comprising a base oil of lubricating viscosity and an amount of one or more zinc dialkyldithiophosphate compounds, the lubricant composition having the following ratios: a) a KV40°C to weight percent zinc contributed by the one or more zinc dialkyldithiophosphate compounds based on a total weight of the lubricant composition of greater than 510. 新鮮 The ratio is KV40℃ 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40°C; and b) a ratio of KV40°C to the weight percent phosphorus contributed by the one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition of greater than 560. 新鮮 The ratio is KV40℃ 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40°C.

Description

Technical Field

[0001] The present disclosure relates to engine lubricating oils having improved Sequence VIII performance. In particular, the present disclosure relates to lubricating oils and methods for improving the viscosity shear stability of lubricating oils in engines or other machine parts lubricated with the lubricating oils. The lubricating oils of the present disclosure are useful as internal combustion engine oils or for other applications where the lubricating oil is subjected to heat and oxidative conditions.

Background Art

[0002] Lubricating oils are an important part of modern vehicle design for engine operation and protection. One essential characteristic of engine oil is viscosity, which must be viscous enough to effectively distribute the fluid to the engine parts that require lubrication, but not so viscous that the engine cannot effectively distribute the fluid to the parts that require lubrication. Viscosity is closely related to fuel economy, and the higher the viscosity, the lower the fuel efficiency.

[0003] In addition, the shear resistance of lubricants is very important. The drain intervals of lubricating oils are becoming longer and require more shear-resistant lubricants. Furthermore, since the viscosity of fresh lubricants is very low, further reduction in viscosity due to shear loss can cause damage to metal parts. This is due to the high temperatures and severe operating conditions to which these lubricants are subjected in spark ignition engines. What is needed is a newly designed additive package for lubricants that can control viscosity shear stability over a longer period compared to conventional additive packages.

Summary of the Invention

[0004] The present invention can be described by the following text.

[0005] 1. In a first aspect, the present disclosure relates to a lubricating oil composition, the lubricating oil composition comprising more than 50% by weight of a lubricating viscosity base oil, and an amount of one or more zinc dialkyldithiophosphate compounds, The lubricating oil composition has a ratio of KV40°C to the weight percentage of zinc contributed by one or more zinc dialkyldithiophosphate compounds that is greater than 510, based on the total weight of the lubricating oil composition. 新鮮 where KV40°C 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40°C as measured by ASTM D445.

[0006] 2. The amount of zinc provided by one or more zinc dialkyldithiophosphate compounds can be less than about 1500 ppm, or less than about 1300 ppm, or less than about 1200 ppm, or less than about 1100 ppm, or from about 100 ppm to about 1500 ppm, or from about 300 ppm to about 1300 ppm, or from about 500 ppm to about 1200 ppm, based on the total weight of the lubricating oil composition, for the lubricating oil composition of Paragraph 1.

[0007] 3. KV40°C 新鮮 can be greater than 40 cSt when measured by ASTM D445, for the lubricating oil composition of Paragraph 1 or 2.

[0008] 4. The lubricating oil composition can have a KV100°C of 8.0 cP or more せん断 where KV100°C せん断 is the kinematic viscosity of the lubricating oil composition after stripping at 100°C for 10 hours as measured by ASTM D445, for any one of the lubricating oil compositions of Paragraphs 1 - 3.

[0009] 5. One or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols, one or more secondary alkyl alcohols, or a combination thereof, for any one of the lubricating oil compositions of Paragraphs 1 - 4.

[0010] 6. One or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols having alkyl groups each having 3 - 8 carbon atoms, for any one of the lubricating oil compositions of Paragraphs 1 - 5.

[0011] 7. A lubricating oil composition according to any one of paragraphs 1 to 6, wherein one or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols selected from the group consisting of n-propyl alcohol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, 2-butanol, n-pentyl alcohol, hexanol, methyl isobutyl carbinol, isohexanol, n-heptanol, isoheptanol, octanol, amyl alcohol, and 2-ethylhexanol.

[0012] 8. A lubricating oil composition according to any one of paragraphs 1 to 7, wherein one or more zinc dialkyldithiophosphate compounds can be derived from one or more secondary alkyl alcohols having an alkyl group having 3 to 8 carbon atoms.

[0013] 9. A lubricating oil composition according to any one of paragraphs 1 to 8, wherein one or more zinc dialkyldithiophosphate compounds can be derived from a secondary alkyl alcohol selected from the group consisting of isopropyl alcohol, amyl alcohol, and methyl isobutyl carbinol.

[0014] 10. A lubricating oil composition according to any one of paragraphs 1 to 9, wherein one or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols and one or more secondary alkyl alcohols.

[0015] 11. A lubricating oil composition according to any one of paragraphs 1 to 10, which may further comprise one or more calcium-containing detergents present in an amount to provide from about 800 ppm to 3000 ppm of calcium, or from about 900 ppm to about 2800 ppm of calcium, based on the lubricating oil composition.

[0016] 12. The lubricating oil composition according to any one of Articles 1 to 11 may include a calcium-containing detergent having a total base number of about 200 mg KOH / g or more, or about 225 mg KOH / g or more, or about 250 mg KOH / g or more, or about 300 mg KOH / g or more, which is an overbased calcium-containing detergent.

[0017] 13. The lubricating oil composition according to Article 12 may include a detergent selected from a calcium sulfonate detergent, a calcium phenate detergent, or a combination thereof as the one or more calcium-containing detergents.

[0018] 14. The lubricating oil composition according to any one of Articles 1 to 13 may further include a viscosity index improver.

[0019] 15. The viscosity index improver may be a copolymer of ethylene-propylene having an average molecular weight of 50,000 to 500,000 when measured by gel permeation chromatography in the lubricating oil composition according to Article 14.

[0020] 17. The lubricating oil composition according to any one of Articles 1 to 16 may further include a nitrogen-containing dispersant present in an amount providing from about 50 ppmw to about 1000 ppmw or from about 100 ppmw to about 900 ppmw.

[0021] 18. In a second aspect, the present disclosure relates to a lubricating oil composition, the lubricating oil composition comprising more than 50% by weight of a base oil having a lubricating viscosity, and a certain amount of one or more zinc dialkyldithiophosphate compounds, and the lubricating oil composition has a ratio of KV40°C to the weight percentage of phosphorus contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition, which is greater than 560, 新鮮 wherein KV40°C 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40°C when measured by ASTM D445.

[0022] 19. The amount of zinc provided by one or more zinc dialkyldithiophosphate compounds can be less than about 1500 ppm, or less than about 1300 ppm, or less than about 1200 ppm, or less than about 1100 ppm, or from about 100 ppm to about 1500 ppm, or from about 300 ppm to about 1300 ppm, or from about 500 ppm to about 1200 ppm, based on the total weight of the lubricating oil composition, the lubricating oil composition of clause 18.

[0023] 20. KV40°C 新鮮 can be greater than 40 cSt when measured by ASTM D445, the lubricating oil composition of clause 18 or 19.

[0024] 21. The lubricating oil composition can have a KV100°C of 8.0 cP or more せん断 and KV100°C せん断 is the kinematic viscosity of the lubricating oil composition after stripping at 100°C for 10 hours when measured by ASTM D445, the lubricating oil composition of any one of clauses 18 - 20.

[0025] 22. One or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols, one or more secondary alkyl alcohols, or a combination thereof, the lubricating oil composition of any one of clauses 18 - 21.

[0026] 23. One or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols having alkyl groups each having 3 - 8 carbon atoms, the lubricating oil composition of any one of clauses 18 - 22.

[0027] 24. A lubricating oil composition according to any one of paragraphs 18 to 23, wherein one or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols selected from the group consisting of n-propyl alcohol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, 2-butanol, n-pentyl alcohol, hexanol, methyl isobutyl carbinol, isohexanol, n-heptanol, isoheptanol, octanol, amyl alcohol, and 2-ethylhexanol.

[0028] 25. A lubricating oil composition according to any one of paragraphs 18 to 24, wherein one or more zinc dialkyldithiophosphate compounds can be derived from one or more secondary alkyl alcohols having an alkyl group having 3 to 8 carbon atoms.

[0029] 26. A lubricating oil composition according to any one of paragraphs 18 to 25, wherein one or more zinc dialkyldithiophosphate compounds can be derived from a secondary alkyl alcohol selected from the group consisting of isopropyl alcohol, amyl alcohol, and methyl isobutyl carbinol.

[0030] 27. A lubricating oil composition according to any one of paragraphs 18 to 26, wherein one or more zinc dialkyldithiophosphate compounds can be derived from one or more primary alkyl alcohols and one or more secondary alkyl alcohols.

[0031] 28. A lubricating oil composition according to any one of paragraphs 18 to 27, which may further comprise one or more calcium-containing detergents present in an amount providing from about 800 ppm to 3000 ppm of calcium, or from about 900 ppm to about 2800 ppm of calcium, based on the lubricating oil composition.

[0032] 29. The lubricating oil composition of paragraph 28 may include a calcium-containing detergent having a total base number of about 200 mg KOH / g or more, or about 225 mg KOH / g or more, or about 250 mg KOH / gram or more, or about 300 mg KOH / g or more, which is an overbased calcium-containing detergent.

[0033] 30. The lubricating oil composition of paragraph 29 may include a detergent selected from a calcium sulfonate detergent, a calcium phenate detergent, or a combination thereof, as one or more calcium-containing detergents.

[0034] 31. The lubricating oil composition of any one of paragraphs 18 to 30 may further include a viscosity index improver.

[0035] 32. The lubricating oil composition of paragraph 31 may be a copolymer of ethylene-propylene having an average molecular weight of 50,000 to 500,000 when measured by gel permeation chromatography, as the viscosity index improver.

[0036] 33. The lubricating oil composition of any one of paragraphs 18 to 32 may further include a nitrogen-containing dispersant present in an amount providing from about 50 ppmw to about 1000 ppmw or from about 100 ppmw to about 900 ppmw.

[0037] 34. In a third aspect, the present disclosure relates to a lubricating oil composition, the lubricating oil composition comprising more than 50% by weight of a base oil of lubricating viscosity, and an amount of one or more zinc dialkyldithiophosphate compounds, and the lubricating oil composition has the following ratio: a) The ratio of the kinematic viscosity at 40 °C (KV40°C) of the fresh lubricating oil composition, as measured by ASTM D445, to the weight percentage of zinc contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition, which is more than 510, and 新鮮 wherein KV40°C 新鮮 is the kinematic viscosity at 40 °C of the fresh lubricating oil composition when measured by ASTM D445, and b) The ratio of the weight % of phosphorus contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition to KV40℃ 新鮮 wherein KV40℃ 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40 °C as measured by ASTM D445, having one or both of the ratios.

[0038] In a fourth aspect, the present disclosure relates to a method of improving the viscosity shear stability of lubricating oil in an engine, the method comprising adding to the engine a lubricating oil composition according to any one of paragraphs 1 to 34.

[0039] The following definitions of terms are provided to clarify the meaning of certain terms used herein.

[0040] The terms "oil composition", "lubrication composition", "lubricating oil composition", "lubricating oil", "lubricant composition", "lubricating composition", "fully formulated lubricant composition", "lubricant", "crankcase oil", "crankcase lubricant", "engine oil", "engine lubricant", "motor oil", and "motor lubricant" are considered to be synonymous and fully interchangeable technical terms that refer to a final lubricating product that includes a minor amount of additive composition in addition to a major amount of base oil.

[0041] As used herein, the terms "additive package", "additive concentrate", "additive composition", "engine oil additive package", "engine oil additive concentrate", "crankcase additive package", "crankcase additive concentrate", "motor oil additive package", "motor oil concentrate" are considered to be synonymous and fully interchangeable technical terms that refer to a portion of a lubricating oil composition excluding a major amount of base oil feedstock mixture. The additive package may or may not include a pour point depressant.

[0042] The term "overbased" refers to metal salts such as sulfonates, carboxylates, salicylates, and / or phenates, where the amount of metal present exceeds the stoichiometric amount. Such salts can have a conversion level greater than 100% (i.e., such salts can contain more than 100% of the theoretical amount of metal required to convert the acid to its "standard salt", "neutral salt"). Often, the expression "metal ratio", abbreviated as MR, is used to indicate the ratio of the total chemical equivalents of metal in an overbased salt to the chemical equivalents of metal in the neutral salt, according to known chemical reactivity and stoichiometry. In the standard or neutral salt, the metal ratio (MR) is 1, but in the overbased salt, the MR is greater than 1. These are generally referred to as overbased, highly basic, or superbasic salts, and may be salts of organic sulfuric acids, carboxylic acids, salicylates, and / or phenols.

[0043] As used herein, the terms "hydrocarbyl substituent" or "hydrocarbyl group" are used in their ordinary meaning, well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly bonded to the remainder of the molecule and having predominantly hydrocarbon characteristics. Each hydrocarbyl group is independently selected from hydrocarbon substituents, and the substituted hydrocarbon substituents contain one or more of halo groups, hydroxyl groups, alkoxy groups, mercapto groups, nitro groups, nitroso groups, amino groups, pyridyl groups, furyl groups, imidazolyl groups, oxygen, and nitrogen, and two or fewer non-hydrocarbon substituents are present per ten carbon atoms in the hydrocarbyl group.

[0044] As used herein, the terms "hydrocarbylene substituent" or "hydrocarbylene group" are used in their ordinary meaning well-known to those skilled in the art. Specifically, it refers to a group that is directly bonded to the remainder of the molecule by carbon atoms at two locations in the molecule and mainly has the characteristics of hydrocarbons. Each hydrocarbylene group is independently selected from divalent hydrocarbon substituents, and the substituted divalent hydrocarbon substituents are halo groups, alkyl groups, aryl groups, alkylaryl groups, arylalkyl groups, hydroxyl groups, alkoxy groups, mercapto groups, nitro groups, nitroso groups, amino groups, pyridyl groups, furyl groups, imidazolyl groups, oxygen, and nitrogen, and two or fewer non-hydrocarbon substituents are present per 10 carbon atoms in the hydrocarbylene group.

[0045] As used herein, the term "weight percent" means the percentage that the stated component represents relative to the total weight of the composition, unless otherwise explicitly stated.

[0046] The terms "soluble", "oil-soluble", or "dispersible" as used herein may indicate that a compound or additive is soluble, soluble, miscible, or suspendable in oil in any proportion, but not necessarily so. However, the foregoing terms mean that they are soluble, suspendable, soluble, or stably dispersible in oil to such an extent that they exhibit their intended effects, for example, in an environment where oil is used. Further, if desired, incorporating other additives may also make it possible to incorporate higher levels of specific additives.

[0047] The term "TBN" as employed herein is used to denote the total base number in units of mg KOH / g when measured by the method of ASTM D2896 or ASTM D4739 or DIN 51639-1.

[0048] The term "alkyl" as used herein refers to a straight-chain, branched, cyclic, and / or substituted saturated chain moiety of from about 1 to about 100 carbon atoms.

[0049] As used herein, the term "alkenyl" refers to a linear, branched, cyclic, and / or substituted unsaturated chain moiety of from about 3 to about 10 carbon atoms.

[0050] As used herein, the term "aryl" refers to monocyclic and polycyclic aromatic compounds which may contain alkyl, alkenyl, alkylaryl, amino, hydroxyl, alkoxy, halo substituents, and / or heteroatoms including, but not limited to, nitrogen, oxygen, and sulfur.

[0051] The lubricants, component combinations, or individual components herein may be suitable for use in various types of internal combustion engines. Suitable engine types may include, but are not limited to, heavy-duty diesel, passenger vehicle, light-duty diesel, medium-speed diesel, or marine engines. The internal combustion engine may be a diesel fuel engine, gasoline fuel engine, natural gas fuel engine, biofuel engine, mixed diesel / biofuel-fuel engine, mixed gasoline / biofuel-fuel engine, alcohol fuel engine, mixed gasoline / alcohol fuel engine, compressed natural gas (CNG) fuel engine, or mixtures thereof. The diesel engine may be a compression ignition engine. The gasoline engine may be a spark ignition engine. The internal combustion engine may also be used in combination with electric or battery power. An engine so configured is commonly known as a hybrid engine. The internal combustion engine may be a two-stroke, four-stroke, or rotary engine. Suitable internal combustion engines include marine diesel engines (such as inland vessels), aircraft piston engines, low-load diesel engines, and engines for motorcycles, automobiles, locomotives, and trucks.

[0052] An internal combustion engine can include one or more components of aluminum alloy, lead, tin, copper, cast iron, magnesium, ceramic, stainless steel, composite materials, and / or mixtures thereof. The components may be coated with, for example, diamond-like carbon coating, lubricating coating, phosphorus-containing coating, molybdenum-containing coating, graphite coating, nanoparticle-containing coating, and / or mixtures thereof. The aluminum alloy may contain aluminum silicate, aluminum oxide, or other ceramic materials. In one embodiment, the aluminum alloy is an aluminum silicate surface. As used herein, the term "aluminum alloy" is synonymous with "aluminum composite" and is intended to describe a component or surface that contains aluminum and another component that mix or react at the microscopic level or near the microscopic level regardless of its detailed structure. This includes not only conventional alloys having metals other than aluminum, but also composite or alloy-like structures having non-metallic elements or compounds such as ceramic-like materials.

[0053] The lubricating oil composition for an internal combustion engine may be suitable for any engine lubricant, regardless of the sulfur, phosphorus, or sulfuric acid ash content (ASTM D - 874). The sulfur content of the engine oil lubricant may be about 1 wt% or less, or about 0.8 wt% or less, or about 0.5 wt% or less, or about 0.3 wt% or less, or about 0.2 wt% or less. In one embodiment, the sulfur content may range from about 0.001 wt% to about 0.5 wt%, or from about 0.01 wt% to about 0.3 wt%. The phosphorus content may be about 0.2 wt% or less, or about 0.1 wt% or less, or about 0.085 wt% or less, or about 0.08 wt% or less, or even about 0.06 wt% or less, about 0.055 wt% or less, or about 0.05 wt% or less. In one embodiment, the phosphorus content may be from about 50 ppm to about 1000 ppm, or from about 325 ppm to about 850 ppm. The total sulfuric acid ash content may be about 2 wt% or less, or about 1.5 wt% or less, or about 1.1 wt% or less, or about 1 wt% or less, or about 0.8 wt% or less, or about 0.5 wt% or less. In one embodiment, the sulfuric acid ash content may be from about 0.05 wt% to about 0.9 wt%, or from 0.1 wt% or about 0.2 wt% to about 0.45 wt%. In another embodiment, the sulfur content may be about 0.4 wt% or less, the phosphorus content may be about 0.08 wt% or less, and the sulfuric acid ash may be about 1 wt% or less. In yet another embodiment, the sulfur content may be about 0.3 wt% or less, the phosphorus content may be about 0.05 wt% or less, and the sulfuric acid ash may be about 0.8 wt% or less.

[0054] In one embodiment, the lubricating oil composition is an engine oil, and the lubricating oil composition may have (i) a sulfur content of about 0.5 wt% or less, (ii) a phosphorus content of about 0.1 wt% or less, and (iii) a sulfuric acid ash content of about 1.5 wt% or less.

[0055] In one embodiment, the lubricating oil composition is suitable for a two-stroke or four-stroke marine diesel internal combustion engine. In one embodiment, the marine diesel combustion engine is a two-stroke engine. In some embodiments, the lubricating oil composition is not suitable for a two-stroke or four-stroke marine diesel internal combustion engine for one or more reasons including, but not limited to, the high sulfur content of the fuel used to power the marine engine and the high TBN required for an engine oil suitable for marine use (e.g., greater than about 40 TBN for an engine oil suitable for marine use).

[0056] In some embodiments, the lubricating oil composition is suitable for use in engines powered by low-sulfur fuels such as fuels containing about 1% to about 5% sulfur. Highway vehicle fuel contains about 15 ppm sulfur (or about 0.0015% sulfur).

[0057] Low-speed diesel typically refers to a marine engine, medium-speed diesel typically refers to a locomotive, and high-speed diesel typically refers to a highway vehicle. The lubricating oil composition may be suitable for only one or all of these types.

[0058] Furthermore, the lubricants of the present specification meet one or more industry specification requirements such as ILSAC GF-3, GF-4, GF-5, GF-5+, GF-6, PC-11, CF, CF-4, CH-4, CK-4, FA-4, CJ-4, CI-4 Plus, CI-4, API SG, SJ, SL, SM, SN, SN PLUS, ACEA A1 / B1, A2 / B2, A3 / B3, A3 / B4, A5 / B5, A7 / B7, C1, C2, C3, C4, C5, C6 E4 / E6 / E7 / E9, Euro 5 / 6, JASO DL-1, Low SAPS, Mid SAPS, or Dexos1 (trademark), Dexos2 (trademark), MB-Approval 229.1, 229.3, 229.5, 22.51 / 229.31, 229.52, 229.6, 229.71, 226.5, 226.51, 228.0 / .1, 228.2 / .3, 228.31, 228.5, 228.51, 228.61, VW 501.01, 502.00, 503.00 / 503.01, 504.00, 505.00, 505.01, 506.00 / 506.01, 507.00, 508.00, 509.00, 508.88, 509.99, BMW Longlife-01, Longlife-01 FE, Longlife-04, Longlife-12 FE, Longlife-14 FE+, Longlife-17 FE+, Porsche A40, C30, Peugeot Citroen Automobiles B71 2290, B71 2294, B71 2295, B71 2296, B71 2297, B71 2300, B71 2302, B71 2312, B71 2007, B71 2008, Renault RN0700, RN0710, RN0720, Ford WSS-M2C153-H, WSS-M2C930-A, WSS-M2C945-A, WSS-M2C913A, WSS-M2C913-B, WSS-M2C913-C, WSS-M2C913-D, WSS-M2C948-B, WSS-M2C948-A, GM 6094-M, Chrysler MS-6395, Fiat 9.55535 G1, G2, M2, N1, N2, Z2, S1, S2, S3, S4, T2, DS1, DSX, GH2, GS1, GSX, CR1, Jaguar Land Rover STJLR.03.5003, STJLR.03.It may also be suitable to meet the specifications of original equipment manufacturers such as 5004, STJLR.03.5005, STJLR.03.5006, STJLR.03.5007, STJLR.51.5122, or any past or future PCMO or HDD specifications not described in this specification. In some embodiments for passenger car motor oil (PCMO) applications, the amount of phosphorus in the final fluid is 1000 ppm or less, or 900 ppm or less, or 800 ppm or less.

[0059] Other hardware may not be suitable for use with the disclosed lubricants. "Functional fluids" include, but are not limited to, various fluids such as tractor hydraulic fluids, power transmission fluids including automatic transmission fluids, continuously variable transmission fluids and manual transmission fluids, hydraulic fluids including tractor hydraulic fluids, some gear oils, power steering fluids, fluids used in wind turbines, compressors, some industrial fluids, and fluids associated with components of power transmission devices. It should be noted that within each of these fluids, such as automatic transmission fluids, there are various different types of fluids for various transmissions with different designs that require fluids with significantly different functional characteristics. This is in contrast to the term "lubricating fluid" which is not used for power generation or transmission.

[0060] For example, with respect to tractor hydraulic fluids, these fluids are general-purpose fluids used for all lubricant applications in tractors except for lubricating the engine. These lubrication applications may include lubrication of the gearbox, power take-off and clutch, rear axle, reduction gears, wet brakes, and hydraulic accessories.

[0061] When the functional fluid is an automatic transmission fluid, the automatic transmission fluid must have sufficient friction for the clutch plate to transmit power. However, the friction coefficient of the fluid tends to decrease due to the influence of temperature as the fluid is heated during operation. It is important for the operating fluid of a tractor or automatic transmission fluid to maintain a high friction coefficient at high temperatures; otherwise, the braking system or automatic transmission may malfunction. This is not a function of engine oil.

[0062] Tractor fluids, such as Super Tractor Universal Oil (STUO) or Universal Tractor Transmission Oil (UTTO), may combine the performance of engine oil with that of transmissions, differentials, final drive planetary gears, wet brakes, and hydraulic performance. Many of the additives used to formulate UTTO or STUO fluids are functionally similar, but if not properly incorporated, they may have detrimental effects. For example, some anti-wear and extreme pressure additives used in engine oils can be highly corrosive to the copper components of hydraulic pumps. Detergents and dispersants used for the performance of gasoline or diesel engines can be harmful to the performance of wet brakes. Friction modifiers specific to quiet wet brake squeal may lack the thermal stability required for engine oil performance. Each of these fluids is designed to meet the specific and stringent requirements of the manufacturer, regardless of functionality, tractor, or lubricity.

[0063] The present disclosure provides a novel lubricating oil blend formulated for use as an automotive crankcase lubricant. The present disclosure provides a novel lubricating oil blend formulated for use as a crankcase lubricant for 2T and / or 4T motorcycles. Embodiments of the present disclosure are suitable for crankcase applications and may provide lubricating oils having improved properties in terms of air entrainment, alcohol fuel compatibility, antioxidant properties, antiwear performance, biofuel compatibility, air bubble reduction characteristics, friction reduction, fuel consumption, pre-ignition prevention, rust prevention, sludge and / or soot dispersibility, piston cleanliness, deposit formation, and water resistance.

[0064] The engine oil of the present disclosure may be formulated by adding one or more additives to a suitable base oil formulation, as described in detail below. The additives may be combined with the base oil in the form of an additive package (or concentrate), or alternatively, may be combined individually with the base oil (or a mixture of both). The fully formulated engine oil may exhibit improved performance characteristics based on the additives added and their respective proportions.

[0065] Further details and advantages of the present disclosure are described in part in the following description and / or may be learned by practice of the present disclosure. The details and advantages of the present disclosure may be realized and achieved by the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claimed present disclosure.

Brief Description of the Drawings

[0066]

Figure 1

Figure 2

[0067] The present disclosure relates to lubricating oil compositions having improved shear stability. In particular, the present disclosure relates to lubricating oil compositions and methods for improving the shear stability of lubricating oils in engines or other mechanical components lubricated with the lubricating oil. The lubricating oils of the present disclosure are useful as passenger vehicle engine oil (PVEO) products, commercial vehicle engine oil (CVEO) products, or for other applications where the lubricating oil is subjected to heat and oxidative conditions.

[0068] The lubricating oil composition of the present invention comprises a base oil having a lubricating viscosity of more than 50% by weight and an amount of one or more zinc dialkyldithiophosphate compounds, and the lubricating oil composition has a ratio of KV40°C to the weight % of zinc contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition over 510. 新鮮 where KV40°C 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40°C as measured by ASTM D445.

[0069] In another embodiment, the lubricating oil composition of the present invention comprises a base oil having a lubricating viscosity of more than 50% by weight and an additive composition containing an amount of one or more zinc dialkyldithiophosphate compounds, and the lubricating oil composition has a ratio of the kinematic viscosity measured at KV40°C to the weight % of phosphorus contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition over 560. 新鮮 where KV40°C 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40°C as measured by ASTM D445.

[0070] As will be discussed in detail below, the lubricating oil composition was tested according to the Sequence VIII engine test for shear stability. The Sequence VIII test (ASTM D6709) is a test method for measuring shear stability under high temperature operating conditions using unleaded gasoline. The shear stability of the oil is determined by comparing the kinematic viscosity of the stripped oil at 100 °C with the kinematic viscosity of the fresh oil at 40 °C. The kinematic viscosity of the fresh oil is measured by ASTM D445 at 40 °C, 100 °C, and then again after the lubricating oil has been stripped at 100 °C for 10 hours.

[0071] In a lubricating oil composition in which the measured shear kinematic viscosity at 100 °C is higher and the ratio of KV40°C to the weight % of zinc contributed by one or more zinc dialkyldithiophosphate compounds, based on the total weight of the lubricating oil composition 新鮮 is greater than 510, or in a lubricating oil composition in which the ratio of KV40°C to the weight % of phosphorus contributed by one or more zinc dialkyldithiophosphate compounds, based on the total weight of the lubricating oil composition 新鮮 is greater than 560, a value of 8.0 cP or greater is found, where KV40°C 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40 °C as measured by ASTM D445.

[0072] Base oil The base oil used in the lubricating oil compositions herein may be selected from any of the base oils in Groups I - V as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five base oil groups are as follows.

[0073]

Table 1

[0074] Groups I, II, and III are mineral oil process stocks. Group IV base oils contain true synthetic molecular species produced by the polymerization of olefinically unsaturated hydrocarbons. Many Group V base oils are also true synthetic products and may include diesters, polyol esters, polyalkylene glycols, alkylated aromatics, polyphosphate esters, polyvinyl ethers, and / or polyphenyl ethers, or may be natural oils such as vegetable oils. Group III base oils are derived from mineral oils, but it should be noted that due to the rigorous processing these fluids undergo, their physical properties become very similar to those of some true synthetic oils such as PAO. Thus, oils derived from Group III base oils may be referred to as synthetic fluids in the industry. Group II+ may include high viscosity index Group II.

[0075] The base oils used in the disclosed lubricating oil compositions can be mineral oils, animal oils, vegetable oils, synthetic oils, synthetic oil blends, or mixtures thereof. Suitable oils can be derived from hydrocracked, hydrogenated, hydrofinished, unrefined oils, refined oils, and re-refined oils, and mixtures thereof.

[0076] Unrefined oils are those derived from natural, mineral, or synthetic sources without or with little further refining treatment. Refined oils are similar to unrefined oils except that they have been treated in one or more refining processes that can result in the improvement of one or more properties. Examples of suitable refining techniques are solvent extraction, secondary distillation, acid or base extraction, filtration, osmosis, etc. Oils refined to a quality suitable for food use may or may not be useful. Edible oils are sometimes also called white oils. In some embodiments, the lubricating oil composition does not contain edible oil or white oil.

[0077] Re-refined oils are also known as recycled or reprocessed oils. These oils are obtained in a similar manner to refined oils using the same or similar processes. Often, these oils are further treated by techniques aimed at removing used additives and oil degradation products.

[0078] Mineral oil can include oil obtained by excavation, or from plants and animals, or any mixture thereof. For example, such oils can include castor oil, lard oil, olive oil, peanut oil, corn oil, soybean oil, and linseed oil, as well as mineral lubricating oils, such as liquid petroleum, and solvent-treated or acid-treated mineral-based lubricating oils of paraffinic, naphthenic, or mixed paraffinic-naphthenic types, but are not limited thereto. Such oils can be partially or fully hydrogenated if desired. Oils derived from coal or shale can also be useful.

[0079] Useful synthetic lubricating oils include hydrocarbon oils, such as polymerized, oligomerized, or interpolymerized olefins (e.g., polybutylene, polypropylene, propylene isobutylene copolymer); poly(1-hexene), poly(1-octene), trimers or oligomers of 1-decene, such as poly(1-decene) (such materials are often referred to as α-olefins), and mixtures thereof; alkyl-benzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di-(2-ethylhexyl)-benzene); polyphenyls (e.g., biphenyl, terphenyl, alkylated polyphenyls); diphenylalkanes, alkylated diphenylalkanes, alkylated diphenyl ethers and alkylated diphenyl sulfides, and their derivatives, analogs, and homologs, or mixtures thereof. Polyalphaolefins are typically hydrogenated materials.

[0080] Other synthetic lubricating oils include polyol esters, diesters, liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, and diethyl ester of decanephosphonic acid), or polymeric tetrahydrofuran. Synthetic oils can be produced by the Fischer-Tropsch reaction and can typically be hydrogenated isomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, the oil can be prepared by Fischer-Tropsch gas-liquid synthesis procedures, as well as other gas-liquid oils.

[0081] The major amount of base oil contained in the lubricating composition can be selected from the group consisting of Group I, Group II, Group III, Group IV, Group V, and combinations of two or more of the foregoing, provided that the major amount of base oil is other than that resulting from the provision of additive components or viscosity index improvers in the composition. In another embodiment, the major amount of base oil contained in the lubricating composition can be selected from the group consisting of Group II, Group III, Group IV, Group V, and combinations of two or more of the foregoing, provided that the major amount of base oil is other than that resulting from the provision of additive components or viscosity index improvers in the composition.

[0082] The amount of oil of lubricating viscosity present may be the remaining balance after subtracting from 100% by weight the total amount of performance additives including viscosity index improvers and / or pour point depressants and / or other top treatment additives. For example, the oil of lubricating viscosity that may be present in the final fluid may be a major amount, such as greater than about 50% by weight, greater than about 60% by weight, greater than about 70% by weight, greater than about 80% by weight, greater than about 85% by weight, or greater than about 90% by weight.

[0083] Zinc dialkyldithiophosphate compound The lubricating oil composition contains an amount of one or more zinc dialkyldithiophosphate compounds (ZDDP).

[0084] The ZDDP is present in the lubricating oil composition in an amount of from about 0.01% to about 15% by weight, or from about 0.01% to about 10% by weight, or from about 0.05% to about 5% by weight, or from about 0.1% to about 3% by weight, or from about 0.1% to about 2% by weight, based on the total weight of the lubricating oil composition.

[0085] The ZDDP compound may contain ZDDP derived from a primary alkyl alcohol, a secondary alkyl alcohol, or a combination of primary and secondary alkyl alcohols. The primary alkyl alcohol and secondary alkyl alcohol used to prepare the ZDDP agent may have an alkyl group containing 1 to 20 carbon atoms, or about 1 to 18 carbon atoms, or about 1 to about 16 carbon atoms, or 2 to 12 carbon atoms, or about 3 to about 8 carbon atoms. Preferably, the primary alkyl alcohol has a branch at the beta carbon compared to the hydroxyl group.

[0086] For example, an alcohol having a branch at the beta (β) carbon would be branched at the second carbon counted from the oxygen atom of the hydroxyl group.

[0087]

Chemical formula

[0088] Suitable examples of the primary alkyl alcohol and secondary alkyl alcohol for use in the preparation of the ZDDP agent may be selected from n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, 2-butanol, isobutyl alcohol, n-pentyl alcohol, amyl alcohol, hexanol, methyl isobutyl carbinol, isohexanol, n-heptanol, isoheptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, and 2-ethylhexanol.

[0089] The molar ratio of primary alkyl alcohol to secondary alkyl alcohol used to prepare ZDDP in the lubricating oil composition is about 100:0 to 0:100, or about 100:0 to 50:50, or 100:0 to 60:40. Preferably, the molar ratio of primary alkyl alcohol to secondary alkyl alcohol used to prepare ZDDP in the lubricating oil composition is 100:0 or 0:100. ZDDP can have a P:Zn ratio of about 1.08 to 1.3, or about 1.08 to 1.2, or about 1.09 to about 1.15.

[0090] In some embodiments, the additive composition comprises at least two different zinc dialkyldithiophosphate compounds. The two alkyl groups on the zinc dialkyldithiophosphate compound may be the same or different.

[0091] In some embodiments, the alkyl groups of 100 mole percent of one or more zinc dialkyldithiophosphate compounds may be derived from one or more primary alcohol groups. In some embodiments, the alkyl groups of 100 mole percent of one or more zinc dialkyldithiophosphate compounds may be derived from one or more secondary alcohol groups. In some embodiments, a mixture of one or more zinc dialkyldithiophosphate compounds derived from one or more primary alcohol groups and one or more zinc dialkyldithiophosphate compounds derived from one or more secondary alcohol groups may be present.

[0092] Alcohols suitable for forming zinc dialkyldithiophosphate salts may be primary alkyl alcohols or secondary alkyl alcohols. In an embodiment, the additive package comprises two or more zinc dialkyldithiophosphate salts that are first derived from an alcohol containing a primary alkyl group and a second zinc dialkyldithiophosphate salt derived from an alcohol containing a secondary alkyl group. In another embodiment, the zinc dialkyldithiophosphate compound is derived from at least two secondary alcohol groups. The alcohol may contain any of a branched chain, a cyclic chain, or a straight chain.

[0093] One or more zinc dialkyldithiophosphate salts may be oil-soluble salts of dihydrocarbyl dithiophosphoric acid and may be represented by the following formula:

[0094] [Chemical formula] In the formula, R5 and R6 may be the same or different alkyl groups containing from 1 to 20 carbon atoms, or from about 1 to 18 carbon atoms, or from about 1 to about 16 carbon atoms, or from 2 to 12 carbon atoms, or from about 3 to about 8 carbon atoms, and containing moieties such as alkyl and cycloalkyl moieties. Thus, the moieties may be, for example, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl, n-octyl, decyl, dodecyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, 2-ethylhexyl, cyclohexyl, or methylcyclopentyl.

[0095] The average number of total carbon atoms per mole of phosphorus in the ZDDP compound may be calculated by dividing the sum of the carbon atoms of the four alkyl groups R5 and R6 provided to the ZDDP compound by the alcohol used in the preparation of the ZDDP compound by 2. For example, in a single ZDDP compound, when R5 is a C3-alkyl group and R6 is a C6 alkyl group, the total number of carbon atoms is 3 + 3 + 6 + 6 = 18. Dividing this by 2 moles of phosphorus per mole of ZDDP gives an average total number of carbon atoms per mole of phosphorus of 9.

[0096] The average total number of carbon atoms per mole of phosphorus (ATCP) for a composition containing one or more ZDDP compounds can be calculated from the alcohol used to produce the ZDDP compound according to the following formula: ATCP = 2 * [(mol% of alc1 * (number of C atoms in alc1) + (mol% of alc2* (Number of C atoms in alc2) + (mol% of alc3 * (Number of C atoms in alc3) +... etc.] In the formula, alc1, alc2, and alc3 each represent different alcohols used to prepare the ZDDP compound, and mol% is the molar percentage of each alcohol present in the reaction mixture used to prepare the ZDDP compound. "~ etc." indicates that when preparing the ZDDP compound using more than three alcohols, the formula can be extended to include each alcohol present in the reaction mixture.

[0097] The average total number of carbon atoms from both R5 and R6 of ZDDP is more than 2 carbon atoms per mole of phosphorus. In one embodiment, it is in the range of more than 4 to 40 carbon atoms, or more than 6 to about 20 carbon atoms. In one embodiment, it is in the range of more than 6 to about 16 carbon atoms. In one embodiment, it is in the range of about 6 to about 15 carbon atoms. In one embodiment, it is in the range of about 9 to about 15 carbon atoms. In one embodiment, it is about 12 carbon atoms per mole of phosphorus.

[0098] The zinc salt of dialkyldithiophosphate may be prepared according to known techniques by first forming dialkyldithiophosphoric acid (DDPA) usually by the reaction of one or more alcohols, and then neutralizing the formed DDPA with a zinc compound. Any basic or neutral zinc compound may be used to prepare the zinc salt, but oxides, hydroxides, and carbonates are most commonly used. The zinc dialkyldithiophosphate of component (i) may be prepared by a process such as the process generally described in U.S. Patent No. 7,368,596.

[0099] In some embodiments, at least one zinc dialkyldithiophosphate salt may be present in the lubricating oil in an amount sufficient to provide from about 10 ppmw zinc to about 1300 ppmw zinc, or from about 100 ppmw zinc to about 1200 ppmw zinc, or from about 200 ppmw zinc to about 1100 ppmw zinc, based on the total weight of the lubricating oil composition.

[0100] In some embodiments, at least one zinc dialkyldithiophosphate salt may be present in the lubricating oil in an amount sufficient to provide from about 100 to about 1200 ppm phosphorus, or from about 200 to about 1100 ppm phosphorus, or from about 300 to about 1000 ppm phosphorus, or from about 400 to about 1000 ppm phosphorus, or from about 550 to about 1000 ppm phosphorus, based on the total weight of the lubricating oil composition.

[0101] The present invention may include overbased ZDDP, which is a basic ZDDP. The term basic ZDDP, or equivalent expression, is used herein to describe zinc salts in which the metal substituents are present in a stoichiometrically greater amount than the phosphate radicals. For example, a normal or neutral zinc phosphorodithioate has 2 equivalents (i.e., 1 mole) of zinc per 2 equivalents (i.e., 2 moles) of phosphorodithioic acid, while a basic zinc diorganophosphorodithioate has more than 2 equivalents of zinc per 2 equivalents of phosphorodithioic acid.

[0102] For example, overbasing can be carried out using a basic zinc compound such as zinc oxide. The amount of the basic base compound required to impart the desired overbasing is not critical. The essential factor is that a sufficient amount of zinc compound is present in the reaction mixture for the overbasing reaction. Although not absolutely essential, it has been found that the reaction proceeds in a more satisfactory manner when using a slightly excess amount of zinc compound than the amount required for the reaction. This excess should be maintained at a minimum level with respect to the need to remove large amounts of solids from the final product. As a general statement, the excess zinc compound should not exceed 10 - 15 wt%.

[0103] Detergent The lubricating oil composition may include one or more detergents including one or more calcium-containing detergents.

[0104] The one or more detergents may be neutral, low-base, or overbased detergents, and mixtures thereof. Suitable detergent substrates include phenates, sulfur-containing phenates, sulfonates, calixalates, salixalates, salicylates, carboxylic acids, phosphoric acids, mono- and / or di-thiophosphoric acids, alkylphenols, sulfur-bonded alkylphenol compounds, or methylene-bridged phenols. Suitable detergents and methods for their preparation are described in more detail in a number of patent publications including U.S. Patent No. 7,732,390 and the references cited therein.

[0105] In addition to calcium, the one or more detergents may be formed from a detergent substrate salt-formed with an alkali metal or another alkaline earth metal, such as, but not limited to, magnesium, potassium, sodium, lithium, barium, or mixtures thereof. In some embodiments, the detergent does not contain barium.

[0106] Suitable detergents can include salts of petroleum sulfonic acids and long-chain mono- or di-alkylaryl sulfonic acids where the aryl group is benzyl, tolyl, and xylyl. Examples of suitable calcium-containing detergents include, but are not limited to, calcium phenates, calcium sulfur-containing phenates, calcium sulfonates, calcium calixarates, calcium salixarates, calcium salicylates, calcium carboxylic acids, calcium phosphates, calcium mono- and / or di-thiophosphates, calcium alkylphenols, calcium sulfur-bonded alkylphenol compounds, and calcium methylene-bridged phenols. Examples of suitable detergents that can be used with one or more calcium-containing detergents include magnesium phenates, magnesium sulfur-containing phenates, magnesium sulfonates, magnesium calixarates, magnesium salixarates, magnesium salicylates, magnesium carboxylic acids, magnesium phosphates, magnesium mono- and / or di-thiophosphates, magnesium alkylphenols, magnesium sulfur-bonded alkylphenol compounds, magnesium methylene-bridged phenols, sodium phenates, sodium sulfur-containing phenates, sodium sulfonates, sodium calixarates, sodium salixarates, sodium salicylates, sodium carboxylic acids, sodium phosphates, sodium mono- and / or di-thiophosphates, sodium alkylphenols, sodium sulfur-bonded alkylphenol compounds, or sodium methylene-bridged phenols.

[0107] One or more of the detergents can be overbased detergents. Such detergent additives can be prepared by reacting a metal oxide or metal hydroxide with a substrate and carbon dioxide gas. The substrate is typically an acid, such as an acid like an aliphatic-substituted sulfonic acid, an aliphatic-substituted carboxylic acid, or an aliphatic-substituted phenol.

[0108] The term "overbased" relates to metal salts such as sulfonates, carboxylates, and phenates of metals where the amount of metal present exceeds the stoichiometric amount. Such salts can have a conversion level greater than 100% (i.e., such salts can contain more than 100% of the theoretical amount of metal required to convert the acid to its "standard salt", "neutral salt"). Often, the expression "metal ratio", abbreviated as MR, is used to indicate the ratio of the total chemical equivalent of the metal in the overbased salt to the chemical equivalent of the metal in the neutral salt, according to known chemical reactivity and stoichiometry. In the standard or neutral salt, the metal ratio (MR) is 1, but in the overbased salt, the MR is greater than 1. They are generally referred to as overbased, highly basic, or superbasic salts and can be salts of organic sulfuric acids, carboxylic acids, or phenols.

[0109] The overbased detergent of the lubricating oil composition can have a total base number (TBN) of about 200 mg KOH / gram or more, or as a further example, about 225 mg KOH / g or more, or about 250 mg KOH / gram or more, or about 300 mg KOH / gram or more, or about 350 mg KOH / gram or more, or about 375 mg KOH / gram or more, or about 400 mg KOH / gram or more.

[0110] Preferably, one or more calcium-containing detergents may include overbased calcium-containing detergents. Examples of suitable overbased calcium-containing detergents include overbased calcium phenate, overbased calcium sulfur-containing phenate, overbased calcium sulfonate, overbased calcium calixarate, overbased calcium salixarate, overbased calcium salicylate, overbased calcium carboxylic acid, overbased calcium phosphate, overbased calcium monothiophosphate and / or dithiophosphate, overbased calcium alkylphenol, overbased calcium sulfur-bonded alkylphenol compound, and overbased calcium methylene-bridged phenol, but are not limited thereto. Preferably, the overbased calcium-containing detergent is an overbased calcium sulfonate detergent.

[0111] Examples of other suitable overbased detergents that can be used with one or more calcium-containing detergents include overbased magnesium phenolate, overbased magnesium sulfur-containing phenate, overbased magnesium sulfonate, overbased magnesium calixarate, overbased magnesium salixarate, overbased magnesium salicylate, overbased magnesium carboxylate, overbased magnesium phosphate, overbased magnesium mono- and / or di-thiophosphate, overbased magnesium alkylphenol, overbased magnesium sulfur-bonded alkylphenol compound, or overbased magnesium methylene-bridged phenol, but are not limited thereto.

[0112] The overbased detergent can have a metal-to-substrate ratio of 1.1:1 or more, or 2:1 or more, or 4:1 or more, or 5:1 or more, or 7:1 or more, or 10:1 or more.

[0113] One or more detergents may be a low-base / neutral detergent having a TBN of up to 175 mg KOH / g, or up to 150 mg KOH / g. The calcium-containing detergent may be a low-base / neutral detergent. The low-base neutral calcium-containing detergent may be selected from calcium sulfonate detergents, calcium phenate detergents, and calcium salicylate detergents. In some embodiments, the low-base / neutral detergent is a calcium-containing detergent, or a mixture of calcium-containing detergents. In some embodiments, the low-base / neutral detergent is a calcium sulfonate detergent, or a calcium phenate detergent. In an embodiment, one or more detergents include a mixture of one or more low-base / neutral calcium-containing detergents and one or more overbased calcium-containing detergents.

[0114] One or more detergents may include an overbased calcium-containing detergent and a low-base / neutral detergent that is a salt of an alkali metal or alkaline earth metal other than calcium.

[0115] The amount of calcium provided by one or more calcium-containing detergents is greater than about 300 ppmw, or greater than 500 ppmw, or greater than 1000 ppmw, or up to about 4000 ppmw, or up to about 3500 ppmw, or up to about 3000 ppmw, or from about 300 ppmw to about 4000 ppmw, or from about 500 ppmw to about 3500 ppmw, or from about 1000 ppmw to about 3000 ppmw, or from about 1000 ppmw to about 2800 ppmw, based on the total weight of the lubricating oil composition.

[0116] The low-base / neutral detergent can provide calcium in an amount that constitutes at least 0.01 wt% of the calcium provided by the total detergents in the lubricating oil composition. In some embodiments, the low-base / neutral detergent can provide calcium in an amount that constitutes at least 0.5 wt%, or at least 1 wt%, or from 0.01 wt% to 12 wt% of the calcium provided by the total detergents in the lubricating oil composition.

[0117] In certain embodiments, one or more low-base / neutral detergents provide from about 0 ppmw to about 1000 ppmw of calcium to the lubricating oil composition, based on the total weight of the lubricating oil composition. In some embodiments, one or more low-base / neutral calcium-containing detergents provide from 25 ppmw to less than 800 ppmw, or from 50 ppmw to 600 ppmw, or from 70 to 300 ppmw of calcium to the lubricating oil composition, based on the total weight of the lubricating oil composition.

[0118] In some embodiments, the detergent is effective to suspend harmful products formed in the lubricating oil composition during engine use.

[0119] One or more detergents may be present in an amount from about 0 wt% to about 10 wt%, or from about 0.1 wt% to about 8 wt%, or from about 1 wt% to about 4 wt%, or greater than about 4 wt% to about 8 wt%, based on the total weight of the lubricating oil composition.

[0120] Viscosity modifier The lubricating oil composition of the present disclosure includes one or more viscosity modifiers (also known as viscosity index improvers and viscosity improvers). The viscosity modifier provides a lubricant having high-temperature and low-temperature operability. These additives impart shear stability at high temperatures and an acceptable viscosity at low temperatures. The viscosity modifier may be one or more dispersant viscosity modifiers that function as both a viscosity modifier and a dispersant. Preferably, the lubricating oil composition includes one or more non-dispersant viscosity modifiers.

[0121] The one or more non-dispersant viscosity modifiers can be hydrocarbon polymers that may have a backbone consisting essentially of aliphatic olefins, particularly alpha-olefin monomers. Thus, the polyolefins of this embodiment exclude polymers having a large component of other types of monomers copolymerized in the main polymer such as ester monomers, acid monomers, etc. The polyolefin may contain other monomers in an amount of such materials of impurities, for example, less than 5% by weight, more often less than 1% by weight, preferably less than 0.1% by weight. Useful polymers include copolymers of ethylene and C3-C 28 alpha-olefins, or copolymers of ethylene and C3-C8 alpha-olefins, or copolymers of ethylene and C3-C6 alpha-olefins, or copolymers of ethylene and C3-C4 alpha-olefins that are oil-soluble or dispersible.

[0122] Olefin copolymers (sometimes referred to as polyolefins) may be random copolymers, block copolymers, and random block copolymers. Ethylene propylene copolymers are usually random or statistical copolymers. Random or statistical copolymers can be a mixture of two or more polymers made in two or more reactors in series. Block copolymers may be obtained by conducting the reaction in a tubular reactor. Such a procedure is described in U.S. Patent No. 4,804,794, which is hereby incorporated by reference for related disclosures in this regard. These polymers are commercially available as PARATONE® 8941 and PARATONE® 8910 (sold by Chevron Oronite Company L.L.C.). Block copolymers can also be obtained by selecting an appropriate catalyst and / or process for polymerization. Such polymers are described in U.S. Patent Application Publication No. 2006 / 0199896, which is hereby incorporated by reference for related disclosures in this regard. Such olefin block copolymers are commercially available from Dow Chemical under the trade name INFUSE™ olefin block copolymers.

[0123] Numerous U.S. patents include the preparation of copolymers of alpha olefins. Copolymers of ethylene and higher alpha olefins are the most common copolymers of aliphatic olefins. Ethylene-propylene copolymers are the most common ethylene-alpha-olefin copolymers and are preferred for use in the present invention. A description of ethylene-propylene copolymers can be found in U.S. Patent No. 4,137,185, which is incorporated herein by reference. Useful ethylene-alpha olefins, usually ethylene-propylene copolymers, are commercially available. Ethylene-alpha olefin copolymers containing from about 30 to about 60 weight percent of monomer units derived from ethylene are generally referred to as low ethylene or amorphous copolymers. Ethylene-alpha olefin copolymers containing from about 60 to about 80 weight percent of units derived from ethylene are generally referred to as high ethylene (semicrystalline) polymers. In an embodiment, one or more non-dispersant viscosity modifiers are ethylene-propylene copolymers having from about 40 to about 60 weight percent ethylene and from about 60 to about 40 weight percent propylene, where the weight percents are based on the total weight of the olefin polymer. In another embodiment, the olefin polymer is an ethylene-propylene copolymer having from about 45 to about 55 weight percent ethylene and from about 55 to about 45 weight percent propylene, where the weight percents are based on the total weight of the olefin polymer. The polymer backbone (i.e., the portion of the olefin polymer that is a backbone without substituents) can also contain a mixture of amorphous and semicrystalline polymers in a weight ratio as described in U.S. Patent No. 5,427,702, which is incorporated herein by reference. Typical commercially available polymers containing amorphous copolymers are PARATONE® 8921 available from Chevron Oronite, LZ7067, LZ7065, and LZ7060 available from Lubrizol Corporation, Keltan® 1200A, 1200B available from Lanxess, and NDR125 available from Dow Chemical Company.

[0124] Olefin polymers having a backbone consisting essentially of aliphatic olefins (sometimes referred to as polyolefins) can be polymers containing dienes. The olefin polymer may be a homopolymer or copolymer of one or more dienes. The diene may be conjugated, such as isoprene, butadiene, 2,3-dimethyl-1,3-butadiene, chloroprene, 1,3-butadiene, and piperylene, or non-conjugated, such as 1,4-hexadiene, ethylidene norbornene, vinyl norbornene, 4-vinylcyclohexene, and dicyclopentadiene. Polymers of conjugated dienes are preferred. In an embodiment, the total carbon content of the diene may not exceed 20 carbons. Such polymers are conveniently prepared via free radical polymerization techniques and anionic polymerization techniques. Emulsion techniques are commonly used for free radical polymerization.

[0125] Olefin polymers having a backbone consisting essentially of aliphatic olefins can be copolymers of a conjugated diene and a vinyl-substituted aromatic compound. In one embodiment, the olefin polymer is a copolymer of a vinyl-substituted aromatic compound and a conjugated diene. This vinyl-substituted aromatic generally contains from 8 to about 20 carbon atoms, preferably from 8 to 12 carbon atoms, and most preferably 8 or 9 carbon atoms. Examples of vinyl-substituted aromatic compounds include vinyl anthracene, vinyl naphthalene, and vinyl benzene (styrene compounds). Styrene compounds are preferred, and examples thereof are styrene, alpha-methylstyrene, ortho-methylstyrene, meta-methylstyrene, para-methylstyrene, para-tertiary-butylstyrene, and chlorostyrene, with styrene being preferred. The vinyl-substituted aromatic content of these copolymers typically ranges from about 15 wt% to about 70 wt%, or from about 20 wt% to about 40 wt%, based on the total weight of the copolymer. The aliphatic conjugated diene content of these copolymers typically ranges from about 30 wt% to about 85 wt%, or from about 60 wt% to about 80 wt%, based on the total weight of the copolymer.

[0126] Polymers, particularly styrene-diene copolymers, can be random copolymers or block copolymers, which can include regular block copolymers or random block copolymers. A random copolymer is a copolymer in which the comonomers are arranged randomly or nearly randomly in the polymer chain and the homopolymer of any monomer is not significantly blocked. A regular block copolymer is a copolymer in which a small number of relatively long chains of the homopolymer of one type of monomer are alternately bonded to a small number of relatively long chains of the homopolymer of another type of monomer. A random block copolymer is a copolymer in which a large number of relatively short segments of the homopolymer of one type of monomer are alternating with relatively short segments of the homopolymer of another monomer. Block copolymers, particularly diblock copolymers, are preferred. Examples of such polymer substrates are illustrated in U.S. Patent Nos. 6,162,768, 6,215,033, 6,248,702, and 6,034,184, which are incorporated herein by reference.

[0127] The random, regular block, and random block polymers used in the present invention may be linear or they may be partially or highly branched. The relative arrangement of the homopolymer segments in a linear regular block or random block polymer is obvious. The difference in structure lies in the number and relative size of the homopolymer segments, and the arrangement in any type of linear block polymer is always alternating in the homopolymer segments.

[0128] Normal or regular block copolymers usually have 1 to about 5, often 1 to about 3, preferably just 1 to about 2 relatively large homopolymer blocks of each monomer. The sizes of the blocks do not necessarily have to be the same and can vary quite a bit. The only requirement is that any regular block copolymer contains relatively few but relatively large alternating homopolymer segments.

[0129] These olefin polymers having a backbone consisting essentially of aliphatic olefins can be hydrogenated to reduce the amount of olefinic unsaturation present in the polymer. They may or may not be fully hydrogenated. Hydrogenation is often achieved using catalytic methods. Catalytic techniques using hydrogen under high pressure and high temperature are well known to those skilled in the chemical arts. Other methods are also useful and are well known to those skilled in the art. A comprehensive discussion of diene polymers can be found in "Encyclopedia of Polymer Science and Engineering", Volume 2, pp. 550-586 and Volume 8, pp. 499-532, Wiley-Interscience (1986), which are hereby expressly incorporated by reference herein for their relevant disclosures in this regard. As a specific example, U.S. Patent No. 3,959,161 teaches the preparation of hydrogenated polybutadiene. In another example, upon hydrogenation, 1,4-polyisoprene becomes an alternating copolymer of ethylene and propylene. Copolymers of conjugated dienes are prepared from two or more conjugated dienes. Useful dienes are the same as those described in the preparation of the above-mentioned homopolymers of conjugated dienes. For example, U.S. Patent No. 4,073,737 describes the preparation and hydrogenation of butadiene-isoprene copolymers.

[0130] The olefin copolymer can have a weight average molecular weight (molecular weight, Mw) determined by gel permeation chromatography using polystyrene standards in the range of about 7,000 g / mol to about 500,000 g / mol, or about 20,000 g / mol to about 400,000 g / mol, or about 100,000 g / mol to about 300,000 g / mol. Exemplary polydispersity values (Mw / Mn) are in the range of about 1.5 to about 10, or about 1.5 to about 3.0, or about 1.7 to about 3.0, or about 2.0 to about 2.5.

[0131] Suitable viscosity modifiers include high molecular weight polyesters or functionalized polyolefins, such as ethylene-propylene copolymers functionalized with the reaction product of an acylating agent (such as maleic anhydride) and an amine, polymethacrylates functionalized with an amine, or esterified maleic anhydride-styrene copolymers reacted with an amine. The typical molecular weight (Mw) of these polymers, as determined by gel permeation chromatography using polystyrene standards, is from 10,000 g / mol to 1,500,000 g / mol, more typically from 20,000 g / mol to 1,200,000 g / mol, and even more typically from 50,000 g / mol to 1,000,000 g / mol.

[0132] Examples of suitable viscosity modifiers include linear or star polymers and copolymers of methacrylates (such as copolymers of alkyl methacrylates of various chain lengths).

[0133] Suitable non-dispersant olefin copolymer viscosity modifiers are non-polar hydrogenated olefin copolymer type viscosity modifiers such as the LUBRIZOL 7075 (trademark) series manufactured by LUBRIZOL (Wickliffe, Ohio). Hydrogenated olefin copolymers are the most widely used type of viscosity modifier for passenger car motor oils and heavy-duty diesel engine oils.

[0134] The shear stability index (SSI) of the polymer backbone (i.e., the portion of the olefin polymer that is a backbone without substituents) is typically in the range of about 3 to about 60, or about 5 to about 50, or about 15 to about 40, or about 25 to about 35. The SSI is measured using test method ASTM-D6278, which evaluates the shear stability of polymer-containing fluids. The test method measures the percent viscosity loss at 100 °C of the polymer-containing fluid when evaluated by the diesel injector device procedure using a European diesel injector test facility. The viscosity loss reflects polymer degradation due to shear at the nozzle.

[0135] In embodiments of the present disclosure, the viscosity modifier and / or dispersant viscosity modifier may be used in an amount greater than about 0.5 wt%, or from about 0.5 wt% to about 30 wt%, or from about 1.0 wt% to about 25 wt%, or from about 2.0 wt% to about 20 wt%, or from about 2.5 wt% to about 15 wt%, or from about 3 wt% to about 10 wt%, or from about 5 wt% to about 10 wt%, based on the total weight of the lubricating oil composition.

[0136] In some embodiments of the present disclosure, the lubricating oil composition includes two or more viscosity modifiers and / or dispersant viscosity modifiers.

[0137] Antioxidant The lubricating oil compositions herein may also optionally contain one or more antioxidants. Antioxidant compounds are known and include, for example, phenates, phenate sulfides, sulfurized olefins, phosphosulfurized terpenes, sulfurized esters, aromatic amines, alkylated diphenylamines (e.g., nonyldiphenylamine, di-nonyldiphenylamine, octyldiphenylamine, di-octyldiphenylamine), phenyl-alpha-naphthylamine, alkylated phenyl-alpha-naphthylamine, hindered non-aromatic amines, phenols, hindered phenols, oil-soluble molybdenum compounds, polymeric antioxidants, or mixtures thereof. The antioxidant compounds may be used alone or in combination.

[0138] The hindered phenol antioxidant may contain a secondary butyl group and / or a tertiary butyl group as a steric hindrance group. The phenol group may be further substituted with a crosslinking group that binds to a hydrocarbyl group and / or a second aromatic group. Examples of suitable hindered phenol antioxidants include 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol or 4-butyl-2,6-di-tert-butylphenol, or 4-dodecyl-2,6-di-tert-butylphenol. In one embodiment, the hindered phenol antioxidant may be an ester and may include, for example, Irganox™ L-135 available from BASF or an addition product derived from 2,6-di-tert-butylphenol and an alkyl acrylate. The alkyl group may contain from about 1 to about 18, or from about 2 to about 12, or from about 2 to about 8, or from about 2 to about 6, or about 4 carbon atoms. Another commercially available hindered phenol antioxidant may be an ester and may include Ethanox™ 4716 available from Albemarle Corporation.

[0139] Useful antioxidants may include diarylamines and high molecular weight phenols. In one embodiment, the lubricating oil composition may contain a mixture of a diarylamine and a high molecular weight phenol, so each antioxidant may be present in an amount sufficient to provide up to about 5% by weight, based on the final weight of the lubricating oil composition. In one embodiment, the antioxidant may be a mixture of about 0.3 to about 1.5% by weight of a diarylamine and about 0.4 to about 2.5% by weight of a high molecular weight phenol, based on the final weight of the present lubricating oil composition.

[0140] Examples of suitable olefins that can be sulfided to form sulfided olefins include propylene, butylene, isobutylene, polyisobutylene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, eicosene, or mixtures thereof. In one embodiment, hexadecene, heptadecene, octadecene, nonadecene, eicosene, or mixtures thereof, and their dimers, trimers, and tetramers are particularly useful olefins. Alternatively, the olefin may be a Diels - Alder adduct of a diene such as 1,3 - butadiene and an unsaturated ester such as butyl acrylate.

[0141] Another class of sulfided olefins includes sulfided fatty acids and their esters. Fatty acids are often obtained from vegetable or animal oils and typically contain from about 4 to about 22 carbon atoms. Examples of suitable fatty acids and their esters include triglycerides, oleic acid, linoleic acid, palmitoleic acid, or mixtures thereof. Often, the fatty acids are obtained from lard oil, tall oil, peanut oil, soybean oil, cottonseed oil, sunflower seed oil, or mixtures thereof. The fatty acids and / or esters can be mixed with olefins such as α - olefins.

[0142] In another alternative embodiment, the antioxidant composition also contains a molybdenum - containing antioxidant in addition to the phenolic and / or amine antioxidants discussed above. When a combination of these three antioxidants is used, preferably the ratio of phenol to amine to molybdenum - containing is (0 - 2):(0 - 2):(0 - 1).

[0143] One or more antioxidants may be present in the lubricating oil composition in the range of about 0 wt% to about 20 wt%, or about 0.1 wt% to about 10 wt%, or about 0.5 wt% to about 5 wt%.

[0144] Wear inhibitor In addition to one or more zinc dialkyldithiophosphates, the lubricating oil compositions herein may also optionally contain one or more other antiwear agents. Examples of suitable antiwear agents include, but are not limited to, metal thiophosphates; metal (other than zinc) dialkyldithiophosphates; phosphate esters or their salts; phosphate esters; phosphites; phosphorus-containing carboxylic acid esters, ethers, or amides; sulfurized olefins; thiocarbamate-containing compounds such as thiocarbamate esters, alkylene-bonded thiocarbamates, and bis(S-alkyldithiocarbamyl) disulfides; and mixtures thereof. A suitable antiwear agent can be molybdenum dithiocarbamate. Phosphorus-containing antiwear agents are fully described by European Patent No. 612839. The metal in the dialkyldithiophosphate salt can be an alkali metal, alkaline earth metal, aluminum, lead, tin, molybdenum, manganese, nickel, copper, or titanium.

[0145] Further examples of suitable antiwear agents include titanium compounds, tartrates, tartrimides, oil-soluble amine salts of phosphorus compounds, sulfurized olefins, phosphites (e.g., dibutyl phosphite), phosphonates, thiocarbamate-containing compounds such as thiocarbamate esters, thiocarbamate amides, thiocarbamic acid ethers, alkylene-bonded thiocarbamates, and bis(S-alkyldithiocarbamyl) disulfides. Tartrates or tartrimides can contain alkyl-ester groups, but the total number of carbon atoms on the alkyl group can be at least 8. The antiwear agent can, in one embodiment, include citrate.

[0146] The antiwear agent may be present in an amount ranging from about 0 wt% to about 15 wt%, or about 0.01 wt% to about 10 wt%, or about 0.05 wt% to about 5 wt%, or about 0.1 wt% to about 3 wt% of the lubricating oil composition.

[0147] Boron-containing compounds The lubricating oil compositions herein may optionally contain one or more boron-containing compounds.

[0148] Examples of boron-containing compounds include borate esters, boric acid fatty amines, boric acid epoxides, boron-containing detergents, and boron-containing dispersants such as, for example, borated succinimide dispersants, as disclosed in U.S. Patent No. 5,883,057.

[0149] When present, the boron-containing compound can be used in an amount sufficient to provide up to about 8 wt%, about 0.01 wt% to about 7 wt%, about 0.05 wt% to about 5 wt%, or about 0.1 wt% to about 3 wt% of the lubricating oil composition.

[0150] Dispersant The lubricating oil composition may optionally further comprise one or more dispersants or mixtures thereof. Dispersants are often referred to as ashless dispersants because they do not contain metals that form ash before being mixed into the lubricating oil composition and typically do not contribute to ash when added to the lubricant. Ashless dispersants are characterized in that the polar group is bonded to a relatively high molecular weight hydrocarbon chain. Typical ashless dispersants include N-substituted long chain alkenyl succinimides. Examples of N-substituted long chain alkenyl succinimides include polyisobutylene succinimides in which the number average molecular weight of the polyisobutylene substituent ranges from about 350 to about 50,000, or up to about 5,000, or up to about 3,000, as measured by GPC. Succinimide dispersants and their preparation are disclosed, for example, in U.S. Patent No. 7,897,696 or U.S. Patent No. 4,234,435. The alkenyl substituent can be prepared from polymerizable monomers containing from about 2 to about 16, or from about 2 to about 8, or from about 2 to about 6 carbon atoms. Succinimide dispersants are typically imides formed from polyamines (typically poly(ethyleneamine)).

[0151] Preferred amines are selected from polyamines and hydroxyamines. Examples of polyamines that can be used include, but are not limited to, higher homologues such as diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and pentaethyleneaminehexamine (PEHA).

[0152] Suitable heavy polyamines contain a small amount of lower polyamine oligomers such as TEPA and PEHA (pentaethylenehexamine), but mainly contain polyalkylene-polyamine mixtures containing more than 6 nitrogen atoms, more than 2 primary amines per molecule, and oligomers with a wider range of branching than conventional polyamine mixtures. The heavy polyamine preferably contains polyamine oligomers containing 7 or more nitrogens per molecule and having more than 2 primary amines per molecule. The heavy polyamine contains more than 28% by weight (for example, more than 32% by weight) of total nitrogen and 120 to 160 grams of equivalent primary amine groups per equivalent.

[0153] In some approaches, suitable polyamines are generally known as PAM and contain mixtures of ethyleneamines in which TEPA and pentaethylenehexamine (PEHA) are the main part and usually less than about 80%.

[0154] Typically, PAM has 8.7 to 8.9 milliequivalents of primary amine per gram (115 to 112 grams of equivalent per equivalent of primary amine) and a total nitrogen content of about 33 to 34% by weight. A heavier cut of PAM oligomers that contains substantially no TEPA and only a very small amount of PEHA but mainly contains more than 6 nitrogens and oligomers with a wider range of branching can produce a dispersant with improved dispersibility.

[0155] In one embodiment, the present disclosure further comprises at least one polyisobutylene succinimide dispersant derived from polyisobutylene having a number average molecular weight in the range of about 350 to about 50,000, or up to about 5,000, or up to about 3,000 when determined by GPC. The polyisobutylene succinimide can be used alone or in combination with other dispersants.

[0156] In some embodiments, when polyisobutylene is included, the polyisobutylene can have a terminal double bond content of greater than 50 mol%, greater than 60 mol%, greater than 70 mol%, greater than 80 mol%, or greater than 90 mol%. Such PIB is also referred to as high reactivity PIB ("HR-PIB"). HR-PIB having a number average molecular weight in the range of about 800 to about 5000 when determined by GPC is suitable for use in embodiments of the present disclosure. Conventional PIB typically has a terminal double bond content of less than 50 mol%, less than 40 mol%, less than 30 mol%, less than 20 mol%, or less than 10 mol%.

[0157] HR-PIB having a number average molecular weight in the range of about 900 to about 3000 when measured by GPC may be suitable. Such HR-PIB can be commercially available or synthesized by the polymerization of isobutene in the presence of a non-chlorinated catalyst such as boron trifluoride as described in U.S. Patent No. 4,152,499 to Boerzel, et al. and U.S. Patent No. 5,739,355 to Gateau, et al. When HR-PIB is used in the above thermal ene reaction, the HR-PIB can result in a higher conversion rate during the reaction and a lower amount of precipitate formation due to the increased reactivity. A suitable method is described in U.S. Patent No. 7,897,696.

[0158] In one embodiment, the present disclosure further comprises at least one dispersant derived from polyisobutylene succinic anhydride ("PIBSA"). PIBSA can have an average of about 1.0 to about 2.0 succinic acid moieties per polymer.

[0159] The active ingredient percentage of the alkenyl or alkyl succinic anhydride can be determined using chromatography techniques. This method is described in columns 5 and 6 of U.S. Patent No. 5,334,321.

[0160] The conversion rate of the polyolefin is calculated from the active ingredient percentage using the formulas in columns 5 and 6 of U.S. Patent No. 5,334,321.

[0161] Unless otherwise specified, all percentages are by weight, and all molecular weights are number average molecular weights determined by gel permeation chromatography (GPC) using a commercially available polystyrene standard (having a number average molecular weight of 180 to about 18,000 as a calibration standard).

[0162] In one embodiment, the dispersant can be derived from polyalphaolefin (PAO) succinic anhydride. In one embodiment, the dispersant can be derived from an olefin maleic anhydride copolymer. As an example, the dispersant can be described as poly-PIBSA. In one embodiment, the dispersant can be derived from an anhydride grafted onto an ethylene-propylene copolymer.

[0163] Suitable types of nitrogen-containing dispersants can be derived from olefin copolymers (OCPs), more specifically, ethylene-propylene dispersants that can be grafted with maleic anhydride. A more complete list of nitrogen-containing compounds that can react with functionalized OCPs is described in U.S. Patent Nos. 7,485,603, 7,786,057, 7,253,231, 6,107,257, and 5,075,383, and / or are commercially available.

[0164] Alternatively, the hydrocarbyl moiety of the hydrocarbyl-dicarboxylic acid or the anhydride of component A) can be derived from an ethylene-alpha olefin copolymer. These copolymers contain a plurality of ethylene units and a plurality of one or more C3-C 10 alpha-olefin units. C3-C10 The alpha-olefin units may include propylene units.

[0165] One type of suitable dispersant can be a Mannich base. Mannich bases are materials formed by the condensation of higher molecular weight alkyl-substituted phenols, polyalkylene polyamines, and aldehydes such as formaldehyde. Mannich bases are described in more detail in U.S. Patent No. 3,634,515.

[0166] A suitable class of dispersants may also be high molecular weight esters or semi-ester amides.

[0167] Suitable dispersants can also be post-treated by reaction with any of a variety of agents by conventional methods. These include boron, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydride, nitriles, epoxides, carbonates, cyclic carbonates, hindered phenol esters, and phosphorus compounds. U.S. Patent No. 7,645,726, U.S. Patent No. 7,214,649, and U.S. Patent No. 8,048,831 are hereby incorporated by reference in their entirety.

[0168] In addition to post-treatment with carbonates and boric acid, the compounds can each be post-treated or further post-treated by a variety of post-treatments designed to improve or impart different properties. Such post-treatments include those summarized in columns 27-29 of U.S. Patent No. 5,241,003, which is hereby incorporated by reference. Such treatments include the following: Inorganic phosphoric acids or anhydrides (e.g., U.S. Patent Nos. 3,403,102 and 4,648,980); Organic phosphorus compounds (e.g., U.S. Patent No. 3,502,677); Phosphorus pentasulfide; Boron compounds as already described above (e.g., U.S. Patent Nos. 3,178,663 and 4,652,387); Carboxylic acids, polycarboxylic acids, anhydrides, and / or acid halides (e.g., U.S. Patent Nos. 3,708,522 and 4,948,386); Epoxides, polyepoxides, or thioepoxides (e.g., U.S. Patent Nos. 3,859,318 and 5,026,495), Aldehydes or ketones (e.g., U.S. Patent No. 3,458,530); Carbon disulfide (e.g., U.S. Patent No. 3,256,185); Glycidol (e.g., U.S. Patent No. 4,617,137); Urea, thiourea, or guanidine (e.g., U.S. Patent Nos. 3,312,619, 3,865,813, and British Patent No. 1,065,595); Organic sulfonic acids (e.g., U.S. Patent No. 3,189,544 and British Patent No. 2,140,811); Alkenyl cyanides (e.g., U.S. Patent Nos. 3,278,550 and 3,366,569); Diketene (e.g., U.S. Patent No. 3,546,243); Diisocyanates (e.g., U.S. Patent No. 3,573,205); Alkanesulfones (e.g., U.S. Patent No. 3,749,695); 1,3 - dicarbonyl compounds (e.g., U.S. Patent No. 4,579,675); Sulfates of alkoxylated alcohols or phenols (e.g., U.S. Patent No. 3,954,639); Cyclic lactones (e.g., U.S. Patent Nos. 4,617,138, 4,645,515, 4,668,246, 4,963,275, and 4,971,711); Cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132, 4,647,390, 4,648,886, 4,670,170); Nitrogen - containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent No. 2,140,811); Hydroxy-protected chlorocarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); Lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patents Nos. 4,614,603 and 4,666,460); Cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patents Nos. 4,612,132, 4,647,390, 4,646,860, and 4,670,170); Nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent No. 2,440,811); Hydroxy-protected chlorocarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); Lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patents Nos. 4,614,603 and 4,666,460); Cyclic carbamates, cyclic thiocarbamates, or cyclic dithiocarbamates (e.g., U.S. Patents Nos. 4,663,062 and 4,666,459); Hydroxy aliphatic carboxylic acids (e.g., U.S. Patents Nos. 4,482,464, 4,521,318, 4,713,189); Oxidizing agents (e.g., U.S. Patent No. 4,379,064); Combinations of phosphorus pentasulfide and polyalkylene polyamines (e.g., U.S. Patent No. 3,185,647); Combinations of carboxylic acids or aldehydes or ketones and sulfur or sulfur chloride (e.g., U.S. Patents Nos. 3,390,086, 3,470,098); Combinations of hydrazine and carbon disulfide (e.g., U.S. Patent No. 3,519,564); Combinations of aldehydes and phenols (e.g., U.S. Patents Nos. 3,649,229, 5,030,249, 5,039,307); Combinations of aldehydes and O-diesters of dithiophosphoric acid (e.g., U.S. Patent No. 3,865,740); Combination of hydroxy aliphatic carboxylic acid and boric acid (e.g., U.S. Patent No. 4,554,086); Combination of hydroxy aliphatic carboxylic acid, subsequent formaldehyde and phenol (e.g., U.S. Patent No. 4,636,322); Combination of hydroxy aliphatic carboxylic acid and subsequent aliphatic dicarboxylic acid (e.g., U.S. Patent No. 4,663,064); Combination of formaldehyde and phenol and subsequent glycolic acid (e.g., U.S. Patent No. 4,699,724); Combination of hydroxy aliphatic carboxylic acid or oxalic acid and subsequent diisocyanate (e.g., U.S. Patent No. 4,713,191); Combination of inorganic acid or anhydride of phosphorus or its partial or whole sulfur analog and boron compound (e.g., U.S. Patent No. 4,857,214); Combination of organic diacid, subsequent unsaturated fatty acid, and subsequent nitroso aromatic amine, optionally followed by boron compound, and subsequent glycolating agent (e.g., U.S. Patent No. 4,973,412); Combination of aldehyde and triazole (e.g., U.S. Patent No. 4,963,278); Combination of aldehyde and triazole and subsequent boron compound (e.g., U.S. Patent No. 4,981,492); Combination of cyclic lactone and boron compound (e.g., U.S. Patent Nos. 4,963,275 and 4,971,711). The above patents are hereby incorporated herein by reference in their entirety.

[0169] The TBN of a suitable dispersant can be about 10 to about 65 when oil-free, which is equivalent to about 5 to about 30 TBN when measured on a dispersant sample containing about 50% diluted oil. TBN is measured by the method of ASTM D2896.

[0170] In certain embodiments, when a dispersant is present, the dispersant is present in an amount that provides from 50 ppmw nitrogen to about 1200 ppmw nitrogen, or from about 100 ppmw nitrogen to about 1000 ppm nitrogen, based on the total weight of the lubricating oil composition.

[0171] When present, the dispersant can be used in an amount sufficient to provide up to about 20 wt% based on the final weight of the lubricating oil composition. Another amount of dispersant that can be used is from about 0.1 wt% to about 15 wt%, or from about 0.1 wt% to about 10 wt%, or from about 0.1 wt% to about 8 wt%, or from about 1 wt% to about 10 wt%, or from about 1 wt% to about 8 wt%, or from about 1 wt% to about 6 wt%, based on the total weight of the lubricating oil composition. In some embodiments, the lubricating oil composition utilizes a mixed dispersant system. A mixture of a single type or two or more types of dispersants in any desired ratio can be used.

[0172] Friction modifier The lubricating oil compositions herein may optionally contain one or more friction modifiers. Suitable friction modifiers may include metal-containing and metal-free friction modifiers and include, but are not limited to, imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amide amines, nitriles, betaines, quaternary amines, imines, amine salts, aminoguanidines, alkanolamides, phosphonic acids, metal-containing compounds, glycerol esters, sulfurized aliphatic compounds and olefins, sunflower oil and other naturally occurring vegetable or animal oils, dicarboxylic acid esters, esters or partial esters of polyols with one or more aliphatic or aromatic carboxylic acids, and the like.

[0173] Suitable friction modifiers may contain a hydrocarbyl group selected from linear, branched, or aromatic hydrocarbyl groups, or mixtures thereof, and may be saturated or unsaturated. The hydrocarbyl group may be composed of carbon and hydrogen or heteroatoms such as sulfur or oxygen. The hydrocarbyl group may range from about 12 to about 25 carbon atoms. In some embodiments, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a mono-ester, or a di-ester, or a (tri)glyceride. The friction modifier may be a long-chain fatty amide, a long-chain fatty ester, a long-chain fatty epoxide derivative, or a long-chain imidazoline.

[0174] Other suitable friction modifiers may include organic, ashless (metal-free), nitrogen-free organic friction modifiers. Such friction modifiers include esters formed by reacting carboxylic acids and anhydrides with alkanols and may generally include polar end groups (such as carboxyl or hydroxyl) covalently bonded to a lipophilic hydrocarbon chain. Examples of organic ashless nitrogen-free friction modifiers are generally known as glycerol monooleate (GMO), which may contain mono-, di-, and tri-esters of oleic acid. Other suitable friction modifiers are described in U.S. Patent No. 6,723,685, which is hereby incorporated by reference in its entirety.

[0175] Amine-based friction modifiers may include amines or polyamines. Such compounds can have a hydrocarbyl group that is linear, either saturated or unsaturated, or a mixture thereof, and may contain from about 12 to about 25 carbon atoms. Further examples of suitable friction modifiers include alkoxylated amines and alkoxylated ether amines. Such compounds can be linear and can have a hydrocarbyl group that is either saturated or unsaturated, or a mixture thereof. They may contain from about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated ether amines.

[0176] Amines and amides can be used by themselves or in the form of adducts or reaction products with boron compounds such as boron oxide, boron halides, metaborates, boric acid or mono-, di- or tri-alkyl borates. Other suitable friction modifiers are described in U.S. Patent No. 6,300,291, which is hereby incorporated by reference in its entirety.

[0177] The friction modifier may optionally be present in the range of about 0 wt% to about 10 wt%, or about 0.01 wt% to about 8 wt%, or about 0.1 wt% to about 4 wt%, etc.

[0178] Molybdenum-containing component The lubricating oil composition herein may optionally also contain one or more molybdenum-containing compounds. Oil-soluble molybdenum compounds may have the functional performance of antiwear agents, antioxidants, friction modifiers, or mixtures thereof. Oil-soluble molybdenum compounds may include molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, molybdenum dithiophosphinate, amine salts of molybdenum compounds, molybdenum xanthate, molybdenum thioxanthate, molybdenum sulfide, molybdenum carboxylate, molybdenum alkoxide, trinuclear organomolybdenum compounds, and / or mixtures thereof. Molybdenum sulfide includes molybdenum disulfide. Molybdenum disulfide can be in the form of a stable dispersion. In one embodiment, the oil-soluble molybdenum compound can be selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, amine salts of molybdenum compounds, and mixtures thereof. In one embodiment, the oil-soluble molybdenum compound can be molybdenum dithiocarbamate.

[0179] Suitable examples of molybdenum compounds that can be used include commercially available materials sold under trade names such as Molyvan 822 (trademark), Molyvan (trademark) A, Molyvan 2000 (trademark), Molyvan 1055 (trademark), and Molyvan 855 (trademark) from R.T. Vanderbilt Co., Ltd., and Sakura-Lube (trademark) S-165, S-200, S-300, S-310G, S-525, S-600, S-700, and S-710 available from Adeka Corporation, and mixtures thereof. Suitable molybdenum components are described in U.S. Patent No. 5,650,381, U.S. Reissue Patent Nos. 37,363 (E1), 38,929 (E1), and 40,595 (E1), the entireties of which are incorporated herein by reference.

[0180] Additionally, the molybdenum compound can be an acidic molybdenum compound. Included are molybdic acid, ammonium molybdate, sodium molybdate, potassium molybdate, and other alkali metal molybdates and other molybdenum salts, such as sodium hydrogen molybdate, MoOCl4, MoO2Br2, Mo2O3Cl6, molybdenum trioxide or similar acidic molybdenum compounds. Alternatively, the composition can provide molybdenum by a molybdenum / sulfur complex of a basic nitrogen compound, as described, for example, in U.S. Patent Nos. 4,263,152, 4,285,822, 4,283,295, 4,272,387, 4,265,773, 4,261,843, 4,259,195, and 4,259,194, and International Publication No. 94 / 06897, the aforementioned patent documents being incorporated herein by reference in their entireties.

[0181] Another class of suitable organomolybdenum compounds are trinuclear molybdenum compounds, such as the formula Mo3S k L n Q zCompounds and mixtures thereof, wherein S represents sulfur, L represents independently selected ligands having an organic group having a sufficient number of carbon atoms to render the compound soluble or dispersible in oil, n is from 1 to 4, k varies from 4 to 7, Q is a neutral electron-donating compound, such as selected from the group of water, amines, alcohols, phosphines, and ethers, z is in the range from 0 to 5, including non-stoichiometric values. Among the organic groups of all ligands, at least 21 total carbon atoms, such as at least 25, at least 30, or at least 35 carbon atoms, may be present. Additional suitable molybdenum compounds are described in U.S. Patent No. 6,723,685, which is hereby incorporated by reference in its entirety.

[0182] The oil-soluble molybdenum compound may be present in an amount sufficient to provide from about 0.5 ppm to about 2000 ppm, from about 1 ppm to about 700 ppm, from about 1 ppm to about 550 ppm, from about 5 ppm to about 300 ppm, or from about 20 ppm to about 250 ppm of molybdenum.

[0183] Transition metal-containing compounds In another embodiment, the oil-soluble compound can be a transition metal-containing compound or a metalloid. Transition metals can include, but are not limited to, titanium, vanadium, copper, zinc, zirconium, molybdenum, tantalum, tungsten, etc. Suitable metalloids include, but are not limited to, boron, silicon, antimony, tellurium, etc.

[0184] In certain embodiments, the oil-soluble transition metal-containing compound can function as an antiwear agent, a friction modifier, an antioxidant, an adhesion control additive, or two or more of these functions. In certain embodiments, the oil-soluble transition metal-containing compound can be an oil-soluble titanium compound such as titanium(IV) alkoxide. Among the titanium-containing compounds that can be used in the preparation of the oil-soluble materials of the disclosed technology or for that purpose, there are various Ti(IV) compounds such as titanium(IV) oxide; titanium(IV) sulfide; titanium(IV) nitrate; titanium(IV) alkoxides such as titanium methoxide, titanium ethoxide, titanium propoxide, titanium isopropoxide, titanium butoxide, titanium 2-ethylhexoxide; and other titanium compounds or complexes such as, but not limited to, titanium phenate; titanium carboxylates such as titanium(IV) 2-ethyl-1,3-hexanedioate or titanium citrate or titanium oleate; and titanium(IV)(triethanolaminato)isopropoxide. Other forms of titanium encompassed by the disclosed technology include titanium phosphates such as titanium dithiophosphate (e.g., dialkyldithiophosphate) and titanium sulfonate (e.g., alkylbenzene sulfonate), or generally reaction products of titanium compounds that form salts such as oil-soluble salts with various acid substances. Thus, the titanium compounds can be derived, inter alia, from organic acids, alcohols, and glycols. The Ti compounds can also exist in dimer or oligomer forms containing a Ti-O-Ti structure. Such titanium materials are commercially available or can be readily prepared by suitable synthetic techniques known to those skilled in the art. Depending on the particular compound, these can exist as solids or liquids at room temperature. These can also be provided in solution form in a suitable inert solvent.

[0185] In one embodiment, titanium can be supplied as a Ti-modified dispersant such as a succinimide dispersant. Such materials can be prepared by forming a titanium mixed anhydride between a titanium alkoxide and a hydrocarbyl-substituted succinic anhydride such as alkenyl- (or alkyl) succinic anhydride. The resulting titanate-succinate intermediate can be used directly or reacted with any of several substances such as (a) a polyamine-based succinimide / amide dispersant having a free condensable -NH functional group; (b) components of a polyamine-based succinimide / amide dispersant, namely, alkenyl (or alkyl) succinic anhydride and polyamine; (c) a hydroxy-containing polyester dispersant prepared by reaction of a substituted succinic anhydride with a polyol, amino alcohol, polyamine, or mixtures thereof. Alternatively, the titanate-succinate intermediate can be reacted with other agents such as an alcohol, amino alcohol, ether alcohol, polyether alcohol or polyol, or a fatty acid, but the product can be used directly to impart Ti to the lubricant or further reacted with a succinic acid dispersant as described above. By way of example, 1 part (mole) of tetraisopropyl titanate can be reacted with about 2 parts (mole) of polyisobutene-substituted succinic anhydride at 140-150 °C for 5-6 hours to provide a titanium-modified dispersant or intermediate. The resulting material (30 g) can be further reacted at 150 °C for 1.5 hours with a succinimide dispersant from a polyisobutene-substituted succinic anhydride and polyethylene polyamine mixture (127 grams + diluent oil) to produce a titanium-modified succinimide dispersant.

[0186] Another titanium-containing compound can be the reaction product of a titanium alkoxide and a C6-C 25 carboxylic acid. The reaction product can be represented by the following formula:

[0187]

Chemical formula

[0188] [Chemical formula] (wherein m + n = 4, n ranges from 1 to 3, R4 is an alkyl moiety having from 1 to 8 carbon atoms, R1 is selected from hydrocarbyl groups containing from about 6 to 25 carbon atoms, and R2 and R3 are the same or different and are selected from hydrocarbyl groups containing from 1 to 6 carbon atoms), or the formula:

[0189] [Chemical formula] (wherein x ranges from 0 to 3, R1 is selected from hydrocarbyl groups containing from about 6 to 25 carbon atoms, R2 and R3 are the same or different and are selected from hydrocarbyl groups containing from about 1 to 6 carbon atoms, and R4 is selected from the group consisting of H, a carboxylic acid moiety of C6 - C 25 ). It can be represented by any of the carboxylic acid moieties of

[0190] Suitable carboxylic acids can include, but are not limited to, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, oleic acid, erucic acid, linoleic acid, linolenic acid, cyclohexanecarboxylic acid, phenylacetic acid, benzoic acid, neodecanoic acid, etc.

[0191] In one embodiment, the oil - soluble titanium compound can be present in the lubricating oil composition in an amount providing from about 0 to about 3000 weight ppm of titanium, or from 25 to about 1500 weight ppm of titanium, or from about 35 weight ppm to about 500 weight ppm of titanium, or from about 50 ppm to about 300 ppm.

[0192] Other optional additives The other additives can be selected to perform one or more functions required for the lubricating fluid. Further, one or more of the aforementioned additives can be multifunctional and can provide additional functions in addition to the functions described herein, or can provide other functions.

[0193] The lubricating oil composition according to the present disclosure may optionally contain other performance additives. The other performance additives may be additional to the specific additives of the present disclosure and / or may include one or more of a metal deactivator, a viscosity index improver, a detergent, an ashless TBN booster, a friction modifier, an antiwear agent, a corrosion inhibitor, a rust inhibitor, a dispersant, a dispersant viscosity index improver, an extreme pressure agent, an antioxidant, an antifoaming agent, a demulsifier, an emulsifier, a pour point depressant, a seal swell agent, and mixtures thereof. Typically, a fully formulated lubricating oil will contain one or more of these performance additives.

[0194] Suitable metal deactivators include derivatives of benzotriazole (typically tolyltriazole), dimercaptothiadiazole derivatives, 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, or 2-alkyldithiobenzothiazole; antifoaming agents including copolymers of ethyl acrylate and 2-ethylhexyl acrylate and optionally vinyl acetate; demulsifiers including trialkyl phosphate, polyethylene glycol, polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers; and pour point depressants including esters of maleic anhydride-styrene, polymethacrylate, polyacrylate, or polyacrylamide.

[0195] Suitable antifoaming agents include silicon-based compounds such as siloxane.

[0196] Suitable pour point depressants may include polymethyl methacrylate or mixtures thereof. The pour point depressant may be present in an amount sufficient to provide from about 0 wt% to about 1 wt%, from about 0.01 wt% to about 0.5 wt%, or from about 0.02 wt% to about 0.04 wt% based on the final weight of the lubricating oil composition.

[0197] A suitable rust inhibitor can be a single compound or a mixture of compounds having the property of suppressing corrosion of the ferrous metal surface. Non-limiting examples of rust inhibitors useful herein include oil-soluble high molecular weight organic acids such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, behenic acid, and serotic acid, and oil-soluble polycarboxylic acids including dimeric and trimeric acids such as those produced from tall oil fatty acid, oleic acid, and linoleic acid. Other suitable corrosion inhibitors include long-chain alpha, omega-dicarboxylic acids in the molecular weight range of about 600 to about 3000, and alkenyl succinic acids having an alkenyl group containing about 10 or more carbon atoms such as tetrapropenyl succinic acid, tetradecenyl succinic acid, and hexadecenyl succinic acid. Another useful type of acidic corrosion inhibitor is a half-ester of an alkenyl succinic acid having about 8 to about 24 carbon atoms in the alkenyl group and an alcohol such as a polyglycol. The corresponding half-amides of such alkenyl succinic acids are also useful. Useful rust inhibitors are high molecular weight organic acids. In some embodiments, the engine oil does not contain a rust inhibitor.

[0198] When present, the rust inhibitor can be used in an amount sufficient to provide from about 0 wt% to about 5 wt%, from about 0.01 wt% to about 3 wt%, from about 0.1 wt% to about 2 wt% based on the final weight of the lubricating oil composition.

[0199] Generally speaking, a suitable crankcase lubricant may contain additive components within the ranges listed in the following table.

[0200]

Table 2

[0201] The percentages of the above components represent the weight % of each component based on the weight of the final lubricating oil composition. The remainder of the lubricating oil composition consists of one or more base oils.

[0202] The additives used when formulating the compositions described herein can be blended into the base oil individually or in various partial combinations. However, it may be suitable to use additive concentrates (i.e., additives plus diluents such as hydrocarbon solvents) to blend all of the components simultaneously.

Examples

[0203] The following examples illustrate, but do not limit, the methods and compositions of the present disclosure. Other suitable modifications and adaptations of the various conditions and parameters commonly encountered in the art and apparent to those skilled in the art are within the spirit and scope of the present disclosure. All patents and publications cited herein are hereby incorporated by reference in their entirety.

[0204] Each of the lubricating oil compositions contained a major amount of a base oil and a base conventional dispersant inhibitor (DI) package. The DI package contained conventional amounts of dispersants, antiwear additives, antioxidants, friction modifiers, antifoam agents, process oils, viscosity improvers, and pour point depressants, as provided in Table 3 below. The major amount of the base oil was a Group II base oil, a Group III base oil, or a mixture thereof. The components that were varied are specified in the tables and discussions of the following examples. All values listed are described as weight percent of the components in the lubricating oil composition (i.e., active ingredients plus diluent oil if any), unless otherwise specified.

[0205]

Table 3

[0206] The lubricating oil composition was tested according to the Sequence VIII engine test. The Sequence VIII test method (ASTM D6709) encompasses the evaluation of both single-viscosity grade and multi-viscosity grade automotive engine oils intended for use in spark-ignition gasoline engines. The test procedure is conducted using a carbureted spark-ignition Cooperative Lubrication Research (CLR) oil test engine (also referred to as the Sequence VIII test engine in this test method), which operates on unleaded fuel. The oil is evaluated for its ability to protect the engine and the oil from degradation under high-temperature and severe usage conditions. The test method can also be used to evaluate the viscosity shear stability of multi-viscosity grade oils. This test method is used to evaluate automotive engine oils with respect to engine protection against bearing weight loss and to evaluate the maintenance of the grade capabilities of multi-viscosity grade oils.

[0207]

Table 4

[0208] The data in Table 4 and Figures 1 and 2 demonstrate the presence of improved KV100°C for a lubricating oil composition containing an amount of one or more zinc dialkyldithiophosphate compounds, and the lubricating oil composition has the following ratio: せん断 is present, and the lubricating oil composition has the following ratio: a) The ratio of KV40℃ to the weight % of zinc contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition, where KV40℃ 新鮮 is the kinematic viscosity of the fresh lubricating oil composition at 40 °C as measured by ASTM D445, and 新鮮 b) The ratio of KV40℃ to the weight % of phosphorus contributed by one or more zinc dialkyldithiophosphate compounds based on the total weight of the lubricating oil composition, where KV40℃ is the kinematic viscosity of the fresh lubricating oil composition at 40 °C as measured by ASTM D445, having one or both of the ratios. 新鮮 This is evident from the fact that the KV100℃ 新鮮 values of Examples IE1 to IE5 of the present invention are higher when compared with the values of Comparative Examples CE1 to CE. せん断

[0209] In addition, the data in Table 4 demonstrate that for lubricating oil compositions formulated with one or more viscosity modifiers in an amount greater than about 5.0 wt% based on the total weight of the lubricating oil composition, there is an improvement in shear stability, i.e., KV100℃ せん断 is 8.0 cP or higher. This is evident from the KV100KC せん断 values of Examples IE1 to IE5 of the present invention when compared with the values of Comparative Examples CE2 to CE4.

[0210] ​​Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. As used throughout the specification and claims, the terms “a” and / or “an” and / or “the” can refer to one or more than one. Unless otherwise indicated, all numbers expressing quantities, ratios, percentages, or other numerical values are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0211] It should be understood that each component, compound, substituent, or parameter disclosed herein is disclosed for use alone or in combination with one or more of any other components, compounds, substituents, or parameters disclosed herein.

[0212] It should be further understood that each range disclosed herein is to be construed as disclosing each specific value within the range having the same number of significant digits. Thus, for example, a range of 1 to 4 is to be construed as disclosing explicitly the values 1, 2, 3, and 4 as well as any range of such values.

[0213] It should be further understood that each lower limit of each range disclosed herein is to be construed as disclosed in combination with each upper limit of each range and each specific value within each range for the same component, compound, substituent, or parameter. Thus, the present disclosure should be construed as disclosing all ranges derived by combining each lower limit of each range with each upper limit of each range, or with each specific value within each range, or by combining each upper limit of each range with each specific value within each range. That is, it is further understood that any range between endpoint values within a broader range is also contemplated herein. Thus, the range of 1 to 4 also means ranges such as 1 to 3, 1 to 2, 2 to 4, 2 to 3, etc.

[0214] Furthermore, a specific amount / value of a component, compound, substituent, or parameter disclosed in the description or examples should be construed as a disclosure of either a lower limit or an upper limit of a range, and thus can form a range for that component, compound, substituent, or parameter in combination with any other lower limit or upper limit or specific amount / value of a range for the same component, compound, substituent, or parameter disclosed elsewhere in the present application.

Claims

**Claim 1** An automotive engine oil composition comprising: a base oil having a lubricating viscosity of more than 50% by weight; a certain amount of one or more zinc dialkyldithiophosphate compounds; one or more viscosity index improvers present in an amount of more than 5.0% by weight based on the total weight of the automotive engine oil composition. The ratio of the kinematic viscosity (KV40°C) of the automotive engine oil composition at 40°C, as measured by ASTM D445, to the weight percentage of zinc contributed by the one or more zinc dialkyldithiophosphate compounds, based on the total weight of the automotive engine oil composition, which is more than 510 新鮮 , where KV40°C 新鮮 is the kinematic viscosity of the fresh automotive engine oil composition at 40°C when measured by ASTM D445, The automotive engine oil composition has a kinematic viscosity (KV) at 100 °C of 8.0 cSt or more せん断 wherein the kinematic viscosity (KV) at 100 °C せん断 is the kinematic viscosity of the automotive engine oil composition after stripping at 100 °C for 10 hours when measured according to ASTM D445, and the kinematic viscosity (KV) at 40 °C 新鮮 is more than 40 cSt when measured according to ASTM D445, an automotive engine oil composition **Claim 2** The automotive engine oil composition according to claim 1, wherein the amount of zinc provided by the one or more zinc dialkyldithiophosphate compounds is less than 1500 ppm based on the total weight of the automotive engine oil composition. **Claim 3** The automotive engine oil composition according to claim 1, wherein the one or more zinc dialkyldithiophosphate compounds are derived from one or more primary alkyl alcohols, one or more secondary alkyl alcohols, or a combination thereof. **Claim 4** The automotive engine oil composition according to claim 1, wherein the one or more zinc dialkyldithiophosphate compounds are derived from one or more primary alkyl alcohols each having an alkyl group with 3 to 8 carbon atoms. **Claim 5** The automotive engine oil composition according to claim 1, wherein the one or more zinc dialkyldithiophosphate compounds are derived from one or more primary alkyl alcohols selected from the group consisting of n-propyl alcohol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, 2-butanol, n-pentyl alcohol, hexanol, methyl isobutyl carbinol, isohexanol, n-heptanol, isoheptanol, octanol, amyl alcohol, and 2-ethylhexanol. **Claim 6** The automotive engine oil composition according to claim 1, wherein the one or more zinc dialkyldithiophosphate compounds are derived from one or more secondary alkyl alcohols each having an alkyl group with 3 to 8 carbon atoms. **Claim 7** The automotive engine oil composition according to claim 1, wherein the one or more zinc dialkyldithiophosphate compounds are derived from one or more secondary alkyl alcohols selected from the group consisting of isopropyl alcohol, amyl alcohol, and methyl isobutyl carbinol. **Claim 8** The automotive engine oil composition according to claim 1, wherein the one or more zinc dialkyldithiophosphate compounds are derived from one or more primary alkyl alcohols and one or more secondary alkyl alcohols. **Claim 9** Further comprising a combination of an overbased calcium sulfonate detergent and an overbased calcium phenate detergent, said combination providing from 800 ppm to 3000 ppm of calcium based on the total weight of said automotive engine oil composition, said overbased calcium sulfonate detergent and said overbased calcium phenate detergent each having a total base number of 200 mg KOH / g or more, The automotive engine oil composition according to claim 1, wherein said one or more zinc dialkyldithiophosphate compounds are derived from one or more secondary alkyl alcohols having an alkyl group having 3 to 8 carbon atoms.

10. The automotive engine oil composition according to claim 1, wherein said viscosity index improver is a copolymer of ethylene-propylene having an average molecular weight of 50,000 to 500,000 when measured by gel permeation chromatography.

11. Further comprising a nitrogen-containing dispersant present in an amount providing from 50 ppmw to 1000 ppmw of nitrogen to said automotive engine oil composition based on the total weight of said automotive engine oil composition, the automotive engine oil composition according to claim 1.

12. An automotive engine oil composition, more than 50% by weight of a base oil having a lubricating viscosity, an amount of one or more zinc dialkyldithiophosphate compounds, and one or more viscosity index improvers present in an amount of more than 5.0% by weight based on the total weight of said automotive engine oil composition. The ratio of the kinematic viscosity at 40°C (KV40°C) of the automotive engine oil composition to the weight percentage of phosphorus contributed by the one or more zinc dialkyldithiophosphate compounds based on the total weight of the automotive engine oil composition, which is more than 560, 新鮮 wherein KV40°C 新鮮 is the kinematic viscosity at 40°C of the fresh automotive engine oil composition as measured by ASTM D445, The automotive engine oil composition has a kinematic viscosity (KV) at 100 °C of 8.0 cSt or more せん断 wherein the KV at 100 °C せん断 is the kinematic viscosity of the automotive engine oil composition after stripping for 10 hours at 100 °C when measured according to ASTM D445, and the KV at 40 °C 新鮮 is more than 40 cSt when measured according to ASTM D445, an automotive engine oil composition.

13. An automotive engine oil composition, more than 50% by weight of a base oil having a lubricating viscosity, an amount of one or more zinc dialkyldithiophosphate compounds, One or more viscosity index improvers present in an amount of more than 5.0% by weight based on the total weight of the automotive engine oil composition, and the automotive engine oil composition has a kinematic viscosity at 100 °C (KV100 °C) of 8.0 cSt or more せん断 where KV100 °C せん断 is the kinematic viscosity of the automotive engine oil composition after stripping for 10 hours at 100 °C when measured by ASTM D445, and KV40 °C 新鮮 is more than 40 cSt when measured by ASTM D445 said automotive engine oil composition having the following ratio: a) The ratio of KV40°C to the weight % of zinc contributed by the one or more zinc dialkyldithiophosphate compounds, based on the total weight of the automotive engine oil composition, above 510, where KV40°C 新鮮 is the kinematic viscosity at 40°C of the fresh automotive engine oil composition when measured by ASTM D445, and 新鮮 the ratio, and b) The ratio of KV40°C to the weight % of phosphorus contributed by the one or more zinc dialkyldithiophosphate compounds based on the total weight of the automotive engine oil composition above 560, where KV40°C 新鮮 is the kinematic viscosity at 40°C of the fresh automotive engine oil composition as measured by ASTM D445, and the automotive engine oil composition having one or both of the ratios. 新鮮 is the kinematic viscosity at 40°C of the fresh automotive engine oil composition as measured by ASTM D445, 新鮮 and the automotive engine oil composition having one or both of the ratios.

14. A method of improving the viscosity shear stability of a lubricating oil in an automotive engine, said method comprising adding the automotive engine oil composition according to claim 13 to the crankcase of said automotive engine.

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