Diesel engine lubricating composition and method of using the same

Abstract

The present disclosure provides a diesel engine lubricating composition and a method for lubricating a diesel engine by supplying the lubricating composition as disclosed herein to the engine. The lubricating composition disclosed herein comprises: between 0.3% and 1.1% by weight total sulfated ash; a kinematic viscosity of less than 8.3 cSt at 100°C; between 0.6% and 2.1% by weight total alkaline earth metal soaps; and a HTHS of less than 2.7 mPa·s as measured according to ASTM D4683. The lubricating composition can be used in diesel engines, particularly heavy-duty diesel engines, to improve one or more of fuel economy and wear protection.

Description

Technical Field

[0001] The present disclosure provides a diesel engine lubricating composition and a method of lubricating the diesel engine by supplying the lubricating composition as disclosed herein to the engine. The lubricating composition disclosed herein can be used in a diesel engine (especially including a heavy-duty diesel engine) to improve one or more of fuel economy and wear protection. Background Art

[0002] Lubricating oil compositions are used for the smooth operation of internal combustion engines. Engine oils for internal combustion engines are used, among other things, to: (i) lubricate the various sliding joints between piston rings and cylinder liners, in the bearings of the crankshaft and connecting rod, and in the valve train, including the cams and valve lifters; (ii) cool the engine; (iii) clean and disperse combustion products; and (iv) prevent corrosion and subsequent rust formation. The stringent demands placed on high-performance engines in recent years have meant greater demands on lubricants used in such engines.

[0003] There is a growing interest in improving the fuel efficiency of internal combustion engines. Vehicle manufacturers have improved fuel economy through engine design, and these improvements have taken advantage of advances in lubricants that provide better oxidation stability, wear protection, and reduced friction. Operators of heavy-duty diesel vehicles have been reluctant to adopt low viscosity grades of engine oil to improve fuel economy; durability (i.e., the ability to keep the vehicle on the road for extended periods of time and mileage) has been and remains a major concern. Therefore, the most widely used viscosity grades for highway heavy-duty diesel vehicles are SAE 15W-40, 10W-30, and 5W-30. In recent years, there has been a continuous push to improve the fuel efficiency of heavy-duty diesel vehicles. Therefore, there is a need to improve the fuel economy of diesel engines without compromising the durability of the engine or otherwise adversely affecting lubricant properties, including deposit and soot control, as well as oxidation resistance and corrosion resistance. This is particularly relevant to viscosity grades lower than SAE 5W-30 (particularly viscosity grades 0W-20, 0W-16, and 0W12).

[0004] Therefore, there is interest in developing lubricating compositions that can be used in diesel engines that may operate under severe conditions and loads while reducing soot and soot-related wear as well as the effects of cleanliness, deposits and better fuel economy. Summary of the Invention

[0005] The present disclosure relates to diesel engine lubricating compositions for use in internal combustion engines, typically compression-ignition engines, to have at least one of reduced soot, improved fuel economy, reduced deposit formation, reduced wear, and improved cleanliness.

[0006] The lubricating composition comprises an oil of lubricating viscosity having greater than 50 wt. % (sometimes referred to as "wt. %) of a Group III base oil, a Group IV base oil, a Group V base oil, or a mixture thereof. The composition further comprises a first PIB succinimide dispersant derived from a PIB having an Mn of 1800 to 2500 and a second PIB succinimide dispersant derived from a PIB having an Mn of less than 1600, with the proviso that at least one of the first PIB succinimide dispersant and the second PIB succinimide dispersant is free of boron; an alkaline earth metal salicylate detergent (such as calcium salicylate); an alkaline earth metal sulfonate, wherein the alkaline earth metal sulfonate is present to deliver 0.1 wt. % to 1.2 wt. % of an alkaline earth metal soap to the composition; and a phosphorus antiwear agent present in an amount to deliver 300 ppm to 900 ppm of phosphorus to the lubricating composition.

[0007] The lubricating composition may have: between 0.3 wt% and 1.1 wt% sulfated ash; a kinematic viscosity at 100°C of less than 8.3 cSt; 0.6 wt% to 2.1 wt% total alkaline earth soaps and a HTHS of less than 2.7 mPa.s measured according to ASTM D4683. DETAILED DESCRIPTION

[0008] The present disclosure provides a diesel engine lubricating composition and a method for using the diesel engine lubricating composition. The lubricating composition comprises: an oil of lubricating viscosity having greater than 50 wt. % of a Group III base oil, a Group IV base oil, a Group V base oil, or a mixture thereof; a first PIB succinimide dispersant derived from a PIB having an Mn of 1800 to 2500; a second PIB succinimide dispersant derived from a PIB having an Mn of less than 1600, wherein at least one of the first PIB succinimide dispersant and the second PIB succinimide dispersant is free of boron; an alkaline earth metal salicylate detergent; an alkaline earth metal sulfonate detergent present in an amount to deliver 0.1 wt. % to 1.2 wt. % of an alkaline earth metal soap to the lubricating composition; and a phosphorus antiwear agent present in an amount to deliver 300 ppm to 900 ppm of phosphorus to the lubricating composition. The lubricating compositions disclosed herein also comprise between 0.3 wt% and 0.9 wt% or between 0.3 wt% and 1.1 wt% total sulfated ash, a total alkaline earth soap content of 0.6 wt% to 2.1 wt%, and a HTHS of less than 2.7 mPa.s as measured according to ASTM D4683.

[0009] Oil of lubricating viscosity

[0010] Lubricating compositions disclosed herein include oils with lubricating viscosity. Such oils include natural oils and synthetic oils, oils derived from hydrocracking, hydrogenation and hydrofining, unrefined oils, refined oils, re-refined oils or their mixtures. A more detailed description of unrefined oils, refined oils and re-refined oils is provided in paragraphs

[0054] to

[0056] of International Publication WO2008 / 147704 (similar disclosures are provided in U.S. Patent Application 2010 / 197536, referring to paragraphs

[0072] to

[0073] ). A more detailed description of natural lubricating oils and synthetic lubricating oils is described in paragraphs

[0058] to

[0059] of WO2008 / 147704 (similar disclosures are provided in U.S. Patent Application 2010 / 197536, referring to paragraphs

[0075] to

[0076] ). Synthetic oils may also be produced by the Fischer-Tropsch reaction and may typically be hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, the oil may be produced by a Fischer-Tropsch gas-to-liquids synthesis process and other gas-to-liquids oils.

[0011] Oils of lubricating viscosity may also be defined as defined in Section 1.3, Subheading 1.3, of the April 2008 edition of "Appendix E—API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils." "Basestock Classification." The API guidelines are also summarized in U.S. Patent No. 7,285,516 (see column 11, line 64 to column 12, line 10).

[0012] Group IV (also known as polyalphaolefins or PAOs) are known in the art and are prepared by oligomerization or polymerization of linear alpha olefins. Base oil PAOs are characteristically water-white oils with excellent low temperature viscosity properties (as measured) and a high viscosity index. Typical PAOs suitable for use in internal combustion engines include those with a kinematic viscosity of 3 to 10 m / s. 2 / s polyalphaolefins, such as PAO-4 and PAO-6, which are about 4m / s respectively. 2 / s and 6m 2 / s.

[0013] In addition to traditional Group III and Group IV base oils, low levels of some Group V base oils, particularly Group V ester base oils, may be present. Ester base fluids include esters of monocarboxylic acids with monohydric alcohols; diesters of diols with monocarboxylic acids and dicarboxylic acids with monohydric alcohols; polyol esters of monocarboxylic acids; and polyesters of monoalcohols with polycarboxylic acids, as well as mixtures thereof. Esters can be broadly divided into two categories: synthetic esters and natural esters.

[0014] Synthetic esters can include esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl and alkenyl succinic acids, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl and alkenyl malonic acids) with any of a variety of monohydric alcohols (e.g., butanol, hexanol, dodecanol, 2-ethylhexanol, ethylene glycol, diethylene glycol monoether, and propylene glycol). Specific examples of these esters include dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dideicosyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, and a complex ester formed by reacting 1 mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid. Other synthetic esters include esters prepared from C5 to C12 monocarboxylic acids and polyols and polyol ethers such as neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, and tripentaerythritol. The ester can also be a monoester of a monocarboxylic acid and a monool.

[0015] Natural (or biologically derived) ester refers to a substance derived from a renewable biological resource, an organism or an entity, which is different from a substance derived from oil or an equivalent raw material. Natural fats include fatty acid triglycerides, hydrolyzed or partially hydrolyzed triglycerides or triglycerides through transesterification, such as fatty acid methyl esters (or referred to as FAME). Suitable triglycerides include but are not limited to palm oil, soybean oil, sunflower oil, rapeseed oil, olive oil, linseed oil and related substances. Other sources of triglycerides include but are not limited to algae, animal fat and zooplankton. For example, U.S. Patent Publication 2011 / 0009300A1 describes a method for producing biolubricants from natural triglycerides.

[0016] In one embodiment, the lubricant composition of the present disclosure comprises 0.1 wt % to 10 wt % of an ester base fluid, or 0.25 wt % to 5 wt % or 0.1 wt % to 2 wt % of an ester base fluid. In one embodiment, the lubricant composition comprises no more than 5 wt % of an ester base fluid, no more than 2.5 wt % or no more than 1 wt % of an ester base fluid. In one embodiment, the lubricant composition is free or substantially free (i.e., contains less than 0.2 wt %) of intentionally added ester base fluid.

[0017] In one embodiment, the oil with lubricating viscosity can be a base oil comprising API Class I to Class IV oil, ester or synthetic oil or their mixture. In one embodiment, the oil with lubricating viscosity can be API Class II oil, Class III oil, Class IV oil, ester or synthetic oil or their mixture. In some embodiments, the oil with lubricating viscosity comprises at least 50 % by weight or at least 60 % by weight or at least 70 % by weight or at least 80 % by weight or at least 90 % by weight or at least 95 % by weight or at least 100 % by weight Class III base oil or Class IV base oil or a mixture of Class III base oil and Class IV base oil.

[0018] The amount of oil of lubricating viscosity present is generally the balance remaining after subtracting from 100 weight percent the sum of the amounts of the additives and other performance additives of the disclosed composition.

[0019] The lubricating composition may be in the form of a concentrate and / or a fully formulated lubricant. If the lubricating composition described herein (including the additives disclosed herein) is in the form of a concentrate that can be combined with additional oils to form, in whole or in part, a finished lubricant, the ratio of these additives to the oil of lubricating viscosity and / or to the diluent oil may range from 1:99 to 99:1 by weight or from 80:20 to 10:90 by weight. Typically, the lubricating composition described herein comprises at least 50% by weight, or at least 60% by weight, or at least 70% by weight, or at least 80% by weight of an oil of lubricating viscosity.

[0020] In some embodiments, the oil of lubricating viscosity may comprise an oil having a viscosity of 2.4 m / s measured at 100°C. 2 / s to 6.4m 2 In some embodiments, the kinematic viscosity is 3.8 m / s. 2 / s to 5.0m 2 / s or 5.2m 2 / s to 5.8m 2 / s or 6.0m 2 / s to 6.5m 2 In other embodiments, the kinematic viscosity of the base oil is 4.5 m / s. 2 / s or 4.3m 2 / s or 4.2m 2 / s.

[0021] Polyisobutylene (PIB) succinimide dispersant

[0022] The lubricating composition of the present disclosure also includes a first polyisobutylene succinimide dispersant and a second polyisobutylene succinimide dispersant. References to the polyisobutylene succinimide dispersant herein refer to both the first and second polyisobutylene succinimide dispersants. The difference is that the first polyisobutylene succinimide dispersant is derived from a polyisobutylene moiety having a larger number average molecular weight (Mn) than the PIB of the second polyisobutylene succinimide dispersant.

[0023] The first polyisobutylene succinimide and / or the second polyisobutylene succinimide dispersant can each be prepared (or, as used herein, "derived") from a polyisobutylene ("PIB") succinimide dispersant that is either a "conventional" PIB or a high vinylidene PIB. The difference between conventional polyolefins and high vinylidene polyolefins can be illustrated by reference to the production of PIB. In a process for producing conventional PIB, isobutylene is polymerized in the presence of AlCl3 to produce a mixture of polymers comprising primarily trisubstituted olefin (III) end groups and tetrasubstituted olefin (IV) end groups, with only a very small amount (e.g., less than 20%) of the chains containing terminal vinylidene (I). In an alternative process, isobutylene is polymerized in the presence of a BF3 catalyst to produce a mixture of polymers comprising primarily (e.g., at least 70%) terminal vinylidene groups, minor amounts of tetrasubstituted end groups, and other structures. Materials produced in an alternative process (sometimes referred to as "high vinylidene PIB") are also described in U.S. Patent No. 6,165,235, which is incorporated herein by reference in its entirety. In one embodiment, the polyisobutylene-derived dispersant is a conventional polyisobutylene-derived dispersant. In another embodiment, the polyisobutylene-derived dispersant is a high or medium vinylidene succinimide dispersant. The polyisobutylene-derived dispersants used herein are generally known in the art.

[0024] Polyisobutylene-derived acylating agents can be prepared / obtained / obtainable by reaction with maleic anhydride via an "ene" or "thermal" reaction (also known as direct alkylation). The "ene" reaction mechanism and general reaction conditions are summarized in "Maleic Anhydride," pp. 147-149, edited by B.C. Trivedi and B.C. Culbertson, and published by Plenum Press in 1982. Polyisobutylene-derived dispersants prepared by processes involving an "ene" reaction include dispersants having a carbocyclic ring present in less than 50 mol%, or 0 mol%, to less than 30 mol%, or 0 mol%, to less than 20 mol%, or 0 mol%. The "ene" reaction can have a reaction temperature of 180° C. to less than 300° C., or 200° C. to 250° C., or 200° C. to 220° C.

[0025] Polyisobutylene-derived acylating agents can also be obtained / obtained by a chlorine-assisted process, which generally involves a Diels-Alder reaction, resulting in the formation of a carbocyclic linkage. This process is known to those skilled in the art. The chlorine-assisted process can produce acylating agents having a carbocyclic ring present in 50 mol% or more, or 60 mol% to 100 mol% of the molecule. Both thermal and chlorine-assisted processes are described in more detail in U.S. Patent 7,615,521, columns 4-5, and Preparations A and B.

[0026] Polyisobutylene-derived acylating agents may also be prepared / obtained / obtainable by a free radical process wherein the acylating agent reacts with polyisobutylene in the presence of a free radical initiator. Such free radical processes are well known in the art and may be carried out in the presence of an additional α-olefin.

[0027] Polyisobutylene-derived acylating agents can be obtained by reacting polyisobutylene with an acylating agent (i.e., an ethylenically unsaturated carbonyl compound) to form an acylated polyisobutylene, which can be functionalized with an amine or further alcohol to form a suitable dispersant. Suitable acylating agents include maleic anhydride or its reactive equivalents (such as acids or esters), i.e., succinic acid and their reactive equivalents. In one embodiment, polyisobutylene can be reacted with maleic anhydride to form an acylated product with a conversion between 1 and 2. In one embodiment, monosuccinic acid is reacted with an amine such that the desired product comprises a mixture in which all anhydride present in the acylating agent has been converted to an imide.

[0028] The polyisobutylene derived dispersant may have a carbonyl to nitrogen ratio (CO:N ratio) of 5:1 to 1:10, 2:1 to 1:10, or 2:1 to 1:5, or 2:1 to 1:2. In one embodiment, the dispersant may have a CO:N ratio of 2:1 to 1:10, or 2:1 to 1:5, or 2:1 to 1:2, or 1:1.4 to 1:0.6.

[0029] The polyisobutylene succinimide dispersant of the present disclosure can be prepared by reacting acylated PIB with a suitable amine compound. Suitable amines include one or more hydrocarbyl amines, amino alcohols, polyether amines, or combinations thereof.

[0030] In one embodiment, the hydrocarbyl amine component may comprise at least one aliphatic amine containing at least one amino group capable of condensing with the acyl group to provide a pendant group and at least one additional group containing at least one nitrogen, oxygen, or sulfur atom. Suitable aliphatic amines include polyethylene polyamines (such as tetraethylenepentamine (TEPA), triethylenetetramine (TETA), pentaethylenehexamine (PEHA), and polyamine bottoms), N,N-dimethylaminopropylamine (DMAPA), N-(aminopropyl)morpholine, N,N-diisostearylamidopropylamine, ethanolamine, and combinations thereof.

[0031] In one embodiment, the hydrocarbyl amine component may comprise at least one aromatic amine containing at least one amino group capable of condensing with the acyl group to provide a pendant group and at least one additional group comprising at least one nitrogen, oxygen or sulfur atom, wherein the aromatic amine is selected from the group consisting of: (i) nitro-substituted aniline; (ii) an amine comprising two aromatic moieties linked by a C(O)NR- group, a -C(O)O- group, an -O- group, an N=N- group or a -SO2- group, wherein R is hydrogen or a hydrocarbyl group, one of the aromatic moieties bearing the condensable amino group; (iii) aminoquinoline; (iv) aminobenzimidazole; (v) N,N-dialkylphenylenediamine; (vi) aminodiphenylamine (also known as N,N-phenylenediamine); and (vii) ring-substituted benzylamine.

[0032] In one embodiment, the polyetheramine compound may comprise an amine terminated polyether compound. The amine terminated polyether compound may comprise units derived from ethylene oxide, propylene oxide, butylene oxide, or some combination thereof. Suitable polyether compounds include those available from Huntsman Series of polyetheramines.

[0033] In one embodiment, the first polyisobutylene succinimide dispersant can be prepared by the thermal direct alkylation process described herein. In another embodiment, the second polyisobutylene succinimide dispersant can be prepared by the thermal direct alkylation process described herein.

[0034] The polyisobutylene-derived dispersants described herein can be further described as having a TBN. In one embodiment, the first polyisobutylene succinimide dispersant has a TBN of 15 to 25. In another embodiment, the first polyisobutylene succinimide dispersant has a TBN of 15 to 20. In one embodiment, the second polyisobutylene succinimide dispersant has a TBN of 20 to 35. In another embodiment, the second polyisobutylene succinimide dispersant has a TBN of 25 to 30. In one embodiment, the second polyisobutylene succinimide dispersant has a TBN of 27 to 28.

[0035] In one embodiment, the first polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight ranging from 1720 to 2200. In another embodiment, the first polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight ranging from 1800 to 2100. In one embodiment, the first polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight ranging from 1850 to 2150.

[0036] In one embodiment, the second polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight in the range of 750 to 1600. In another embodiment, the second polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight in the range of 1000 to 1600. In one embodiment, the second polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight in the range of 1200 to 1600. In one embodiment, the second polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight in the range of 800 to 1150. In another embodiment, the second polyisobutylene succinimide dispersant is derived from PIB having a number average molecular weight in the range of 900 to 1100.

[0037] In one embodiment, the first polyisobutylene succinimide dispersant may be present in the lubricating composition in an amount of 0.5 wt % to 10 wt %. In another embodiment, the first polyisobutylene succinimide dispersant may be present in the lubricating composition in an amount of 0.8 wt % to 6 wt %. In one embodiment, the first polyisobutylene succinimide dispersant may be present in the lubricating composition in an amount of 1 wt % to 5 wt %. In one embodiment, the first polyisobutylene succinimide dispersant may be present in the lubricating composition in an amount of 1.1 wt % to 2.2 wt %.

[0038] In one embodiment, the second polyisobutylene succinimide dispersant is present in the lubricating composition in an amount of 1% to 5% by weight. In another embodiment, the second polyisobutylene succinimide dispersant is present in the lubricating composition in an amount of 1.5% to 4.8% by weight. In another embodiment, the second polyisobutylene succinimide dispersant is present in the lubricating composition in an amount of 1.8% to 4.6% by weight. In another embodiment, the second polyisobutylene succinimide dispersant is present in the lubricating composition in an amount of 1.9% to 3.3% by weight.

[0039] In one embodiment, the first polyisobutylene succinimide dispersant may comprise a mixture of two or more dispersants, wherein each of the two or more dispersants falls within a range including, but not limited to, the PIB Mn, TBN, and treat rate of the first polyisobutylene succinimide dispersant as disclosed herein. In another embodiment, the first polyisobutylene succinimide dispersant may comprise a mixture of two dispersants, wherein each of the two dispersants falls within a range including, but not limited to, the PIB Mn, TBN, and treat rate of the first polyisobutylene succinimide dispersant as disclosed herein.

[0040] In some embodiments, the second polyisobutylene succinimide dispersant may comprise a mixture of two or more dispersants, wherein each of the two or more dispersants falls within a range including, but not limited to, the PIB Mn, TBN, and treat rate of the second polyisobutylene succinimide dispersant disclosed herein. In another embodiment, the second polyisobutylene succinimide dispersant comprises 1 wt % to 5 wt % of a PIB succinimide dispersant derived from a PIB having an Mn of 900 to 1100 and 1 wt % to 5 wt % of a PIB succinimide dispersant derived from a PIB having an Mn of 1200 to 1600.

[0041] The lubricating composition of the present disclosure also provides that at least one of the first polyisobutylene succinimide dispersant and the second polyisobutylene succinimide dispersant is free of boron. In one embodiment, the first polyisobutylene succinimide dispersant is free of boron and the second polyisobutylene succinimide dispersant is borated. In another embodiment, the first polyisobutylene succinimide dispersant is borated and the second polyisobutylene succinimide dispersant is free of boron.

[0042] In the preparation of the boron-containing polyisobutylene succinimide dispersant, the first polyisobutylene-derived succinimide dispersant or the second polyisobutylene-derived succinimide dispersant as described herein can be post-treated by conventional methods, including reaction with a boron compound to produce the boron-containing polyisobutylene succinimide dispersant. Suitable boron compounds that can be used to borate the polyisobutylene-derived dispersant include one or more of a variety of agents selected from the group consisting of various forms of boric acid (including metaboric acid HBO2, orthoboric acid H3BO3, and tetraboric acid H2BO7), boron oxide, boron trioxide, and alkyl borates. In one embodiment, the borating agent is boric acid, which can be used alone or in combination with other borating agents. Methods for preparing borated dispersants are known in the art. Borated dispersants can be prepared in such a way that they contain 0.1 wt% to 2.5 wt% boron or 0.1 wt% to 2.0 wt% boron or 0.2 wt% to 1.5 wt% boron or 0.3 wt% to 1.0 wt% boron.

[0043] In some embodiments, the borated first polyisobutylene succinimide dispersant or the borated second polyisobutylene succinimide dispersant is present in an amount to deliver at least 25 ppm, or at least 50 ppm, or at least 75 ppm of boron to the lubricating composition. In another embodiment, either the borated first polyisobutylene succinimide dispersant or the borated second polyisobutylene succinimide dispersant is present in an amount to deliver 25 ppm to 400 ppm of boron to the lubricating composition. In another embodiment, either the borated first polyisobutylene succinimide dispersant or the borated second polyisobutylene succinimide dispersant is present in an amount to deliver 25 ppm to 400 ppm, or 50 ppm to 200 ppm, or 75 ppm to 150 ppm, or 78 ppm to 100 ppm of boron to the lubricating composition.

[0044] detergent

[0045] The lubricating composition of the present disclosure also comprises an alkaline earth metal salicylate detergent and at least one alkaline earth metal sulfonate detergent as described herein. Metal-containing detergents are known in the art. They are generally composed of metal salts (particularly alkali metals and alkaline earth metals) of acidic organic substrates. The metal-containing detergent can be neutral (i.e., a stoichiometric salt of the metal and the substrate, also known as a neutral soap or soap) or overbased.

[0046] Metal overbased detergents (also known as overbased detergents, metal-containing overbased detergents, or superbased salts) are characterized by a metal content in excess of that required for neutralization based on the stoichiometry of the metal and the particular acidic organic compound (i.e., substrate) with which the metal reacts. The overbased detergent may comprise one or more of a sulfonate, a salicylate, a non-sulfur-containing phenate, a sulfur-containing phenate, and mixtures thereof.

[0047] The amount of excess metal relative to the substrate is typically expressed as a metal ratio. The term "metal ratio" is used in the prior art and herein to define the ratio of the total chemical equivalents of metal in the overbased salt to the chemical equivalents of metal in the salt, which is expected to result from the reaction between the hydrocarbyl-substituted organic acid, hydrocarbyl-substituted phenol, or mixture thereof to be overbased and the alkali metal compound, based on the known chemical reactivity and stoichiometry of the two reactants. Thus, in a normal or neutral salt (i.e., soap), the metal ratio is 1, and in an overbased salt, the metal ratio is greater than 1, in particular, greater than 1.3. The overbased metal detergent may have a metal ratio of 5 to 30, or a metal ratio of 7 to 22, or a metal ratio of 11 to 18, or a metal ratio of at least 11.

[0048] Metal-containing detergents may also include "hybrid" detergents formed with mixed surfactant systems that include phenate and / or sulfonate components, such as phenate-salicylate, sulfonate-phenate, sulfonate-salicylate, sulfonate-phenate-salicylate, as described, for example, in U.S. Patents 6,429,178, 6,429,179, 6,153,565, and 6,281,179. In the case of, for example, a mixed sulfonate / salicylate detergent, the mixed detergent would be considered equivalent to the amount of different salicylate and sulfonate detergents incorporating the same amount of salicylate and sulfonate soap, respectively. Overbased phenates and salicylates typically have a total base number (TBN) of 180 to 450 TBN. Overbased sulfonates typically have a total base number (TBN) of 250 to 800 or 300 to 600. Overbased detergents are known in the art.

[0049] Alkylphenols are commonly used as ingredients in overbased detergents and / or as building blocks for overbased detergents. Alkylphenols can be used to prepare phenates, salicylates, salicylate alkoxides, or salicin detergents, or mixtures thereof. Suitable alkylphenols can include para-substituted alkylphenols. The alkyl group can be a straight or branched aliphatic group having 1 to 60 carbon atoms, 8 to 40 carbon atoms, 10 to 24 carbon atoms, 12 to 20 carbon atoms, or 16 to 24 carbon atoms. In one embodiment, the alkylphenol overbased detergent is prepared from an alkylphenol or mixture thereof that is free of or substantially free of (i.e., contains less than 0.1% by weight) p-dodecylphenol. In one embodiment, the lubricating composition contains less than 0.3% by weight of alkylphenol, less than 0.1% by weight of alkylphenol, or less than 0.05% by weight of alkylphenol. In one embodiment, the alkylphenol detergent is a salicylate.

[0050] Alkaline earth metal salicylates

[0051] Salicylate detergents and overbased salicylate detergents can be prepared in at least two different ways. The carbonylation (also referred to as carboxylation) of p-alkylphenols has been described in many references (including U.S. Patent No. 8,399,388). After carbonylation, overbased can be carried out to form overbased salicylate detergents. Suitable p-alkylphenols include those with straight and / or branched hydrocarbon groups having 1 to 60 carbon atoms, 4 to 34 carbon atoms, 14 to 24 carbon atoms and combinations thereof. Salicylate detergents can also be prepared by alkylation of salicylic acid, followed by overbased, as described in U.S. Patent No. 7,009,072. Salicylate detergents prepared in this way can be prepared by straight and / or branched alkylating agents (generally 1-olefins) containing 6 to 50 carbon atoms, 10 to 30 carbon atoms or 14 to 24 carbon atoms. In one embodiment, the overbased detergent is a salicylate detergent. In one embodiment, the salicylate detergent contains no unreacted p-alkylphenol (ie, contains less than 0.1 wt. %). In one embodiment, the salicylate detergent is prepared by the alkylation of salicylic acid.

[0052] In one embodiment, the alkaline earth metal salicylate detergent has a TBN (KOH / g) of 200 to 575 or 200 to 500. In another embodiment, the alkaline earth metal salicylate detergent has a TBN (KOH / g) of 250 to 350. In one embodiment, the alkaline earth metal salicylate detergent has a metal ratio of 2 to 7 or 2 to 4 or 2.5 to 3.5. In one embodiment, the alkaline earth metal salicylate detergent is present in the lubricating composition in an amount of 0.1 wt % to 5 wt %. In another embodiment, the alkaline earth metal salicylate detergent is present in the lubricating composition in an amount of 0.2 wt % to 3 wt %. In one embodiment, the alkaline earth metal salicylate detergent is present in the lubricating composition in an amount of 0.5 wt % to 3 wt %. In one embodiment, the alkaline earth metal salicylate detergent is present in the lubricating composition in an amount of 0.8 wt % to 2.5 wt %. In one embodiment, the calcium alkaline earth metal detergent is present in the lubricating composition in an amount of 0.9 wt % to 2.3 wt %.

[0053] In one embodiment, the alkaline earth metal salicylate detergent can be calcium salicylate, magnesium salicylate, or a combination thereof. In one embodiment, the alkaline earth metal salicylate is calcium salicylate. In one embodiment, the alkaline earth metal salicylate is magnesium salicylate. The calcium salicylate can be present in an amount that delivers 150 ppm to 1500 ppm of calcium to the lubricant composition, or 250 ppm to 1100 ppm of calcium to the composition. The magnesium salicylate can be present in an amount that delivers 100 ppm to 2000 ppm of magnesium to the lubricant composition, or 250 ppm to 1750 ppm of magnesium, or 300 ppm to 1550 ppm of magnesium to the lubricant composition.

[0054] Alkaline earth metal sulfonate detergent

[0055] The alkaline earth metal sulfonate can be a neutral sulfonate (metal ratio less than 1.3), a low overbased detergent (metal ratio of 1.5 to 6), or a high overbased detergent (metal ratio of at least 8), or any combination thereof such that at least 0.1 wt. % of the alkaline earth metal soap is present in the lubricant composition.

[0056] The alkaline earth metal sulfonate detergent can be a linear alkylbenzene sulfonate detergent, as described in paragraphs

[0026] to

[0037] of U.S. Patent Publication 2005 / 065045 (and licensed as US 7,407,919). Linear alkylbenzene sulfonate detergents can be particularly useful for helping improve fuel economy. The linear alkyl group can be attached to the benzene ring at any position along the linear chain of the alkyl group (but typically at the 2, 3, or 4 positions of the linear chain, and in some cases, primarily at the 2 position) to obtain a linear alkylbenzene sulfonate detergent.

[0057] In one embodiment, the alkaline earth metal sulfonate detergent of the present disclosure is selected from calcium sulfonate detergents and magnesium sulfonate detergents. In another embodiment, the alkaline earth metal sulfonate detergent is a calcium sulfonate detergent. In one embodiment, the calcium sulfonate detergent has a TBN of less than 250 on an oil-free basis. In another embodiment, the calcium sulfonate detergent has a TBN of less than 200, or less than 150, or less than 80. In one embodiment, the calcium sulfonate detergent has a TBN of 50 to 90. In one embodiment, the calcium sulfonate has a TBN of 120 mg KOH / g to 250 mg KOH / g and a metal ratio of 1.5 to 5.

[0058] In one embodiment, the alkaline earth metal sulfonate detergent is a calcium sulfonate detergent present in the lubricating composition in an amount of 0.1 wt % to 2.0 wt %. In another embodiment, the calcium sulfonate detergent is present in the lubricating composition in an amount of 0.3 wt % to 1.5 wt %.

[0059] In one embodiment, the alkaline earth metal sulfonate detergent is a magnesium sulfonate detergent. The magnesium sulfonate may have a TBN (mg KOH / g) of 300 to 800 on an oil-free basis. In some embodiments, the magnesium sulfonate may have a TBN (mg KOH / g) of 400 to 750. In other embodiments, the magnesium sulfonate may have a TBN (mg KOH / g) of 250 to 350. In other embodiments, the magnesium sulfonate may have a TBN (mg KOH / g) of 350 to 375. In one embodiment, the magnesium sulfonate may have a metal ratio of 8 to 30, 10 to 25, or 12 to 18.

[0060] In one embodiment, the magnesium sulfonate detergent is present in the lubricating composition in an amount of 0.05 wt % to 0.5 wt % or 0.05 wt % to 0.2 wt %. In another embodiment, the magnesium sulfonate detergent is present in the lubricating composition in an amount of 0.06 wt % to 0.1 wt % or 0.06 wt % to 0.2 wt %.

[0061] In one embodiment, the alkaline earth metal sulfonate may be a combination of at least one neutral or low overbased alkaline earth metal sulfonate (ie, metal ratio less than 6) and at least one highly overbased alkaline earth metal sulfonate (metal ratio of at least 8).

[0062] The alkaline earth metal detergent used herein can be a sodium salt, calcium salt, magnesium salt or a mixture thereof of a sulfonate. In one embodiment, the alkaline earth metal sulfonate detergent is a calcium sulfonate detergent, a magnesium sulfonate detergent or a mixture thereof. In one embodiment, one or more of the calcium sulfonate detergent and the magnesium sulfonate detergent is overbased. In one embodiment, the alkaline earth metal detergent is an overbased calcium sulfonate detergent. In another embodiment, the alkaline earth metal detergent is an overbased magnesium sulfonate detergent. In yet another embodiment, the alkaline earth metal detergent is a mixture of an overbased calcium sulfonate detergent and an overbased magnesium sulfonate detergent. In one embodiment, the alkaline earth metal sulfonate detergent is a mixture of 0.6 wt % to 1.5 wt % of a calcium sulfonate detergent with a TBN (mg KOH / g) of 50 to 200 and 0.04 wt % to 0.1 wt % of an overbased magnesium sulfonate detergent with a TBN (mg KOH / g) of 400 to 800.

[0063] The detergent of the disclosed lubricating composition can include an alkaline earth metal from the detergent. In one embodiment, the calcium salicylate detergent is present in an amount to deliver 150 ppm to 1500 ppm, or 250 ppm to 1100 ppm, or 300 ppm to 800 ppm of calcium to the lubricating composition. In embodiments where the alkaline earth metal detergent comprises a calcium sulfonate detergent, the calcium sulfonate detergent can be present in an amount to deliver 100 ppm to 1000 ppm, 150 ppm to 800 ppm, or 250 ppm to 650 ppm of calcium to the lubricating composition. In embodiments where the alkaline earth metal detergent comprises a magnesium sulfonate detergent, the magnesium sulfonate detergent can be present in an amount to deliver 50 ppm to 500 ppm, 100 ppm to 425 ppm, or 150 ppm to 350 ppm of magnesium to the lubricating composition. In some embodiments, the alkaline earth metal detergent comprises a calcium sulfonate detergent, and the total amount of calcium delivered to the lubricating composition from the calcium salicylate detergent and the calcium sulfonate detergent is: 800 ppm to 2500 ppm, 900 ppm to 1800 ppm, 950 ppm to 1450 ppm calcium delivered to the lubricating composition.

[0064] The metal-containing detergent provides sulfated ash to the lubricating composition. Sulfated ash can be determined by ASTM D874. In one embodiment, the total sulfated ash delivered to the lubricating composition from the alkaline earth salicylate detergent and the alkaline earth metal detergent is 0.25 wt % to 0.95 wt %. In other embodiments, the alkaline earth metal salicylate detergent is present in an amount that delivers 0.05 wt % to 0.5 wt % or 0.1 wt % to 0.35 wt % sulfated ash to the lubricating composition. In another embodiment, the alkaline earth metal detergent is present in an amount that delivers 0.05 wt % to 0.75 wt % or 0.1 wt % to 0.6 wt % sulfated ash to the lubricating composition.

[0065] In addition to ash content and TBN, overbased detergents provide detergent soap (also referred to as neutral detergent) to the lubricating composition. As a metal salt of a substrate, soap can serve as a surfactant in the lubricating composition. In one embodiment, the alkaline earth metal sulfonate detergent is present in an amount that delivers 0.1 wt % to 1.5 wt % or 0.15 wt % to 1.2 wt % or 0.2 wt % to 0.9 wt % sulfonate soap to the lubricating composition. In one embodiment, the alkaline earth metal salicylate detergent is present in an amount that delivers 0.3 wt % to 1.4 wt % or 0.35 wt % to 1.2 wt % or 0.4 wt % to 1.0 wt % salicylate soap to the lubricating composition. In one embodiment, the alkaline earth metal soap can be calcium, magnesium or any mixture thereof. In one embodiment, the alkaline earth metal sulfonate soap is present in an amount of 0.2 wt % to 0.8 wt % of the lubricating composition, and the alkaline earth metal salicylate soap is present in an amount of 0.3 wt % to 1.0 wt % of the lubricating composition. The total amount of all alkaline earth metal detergent soaps may be present in an amount from 0.6 wt % to 2.1 wt % or from 0.7 wt % to 1.4 wt % of the lubricant composition.

[0066] anti-wear agents

[0067] The lubricating compositions of the present disclosure also include one or more phosphorus-containing antiwear agents.

[0068] Phosphorus-containing antiwear agents are well known to those skilled in the art and include metal dialkyl(dithio)phosphates, hydrocarbyl phosphites, hydrocarbyl phosphines, hydrocarbyl phosphonates, alkyl phosphates, amine or ammonium (alkyl)phosphates, and combinations thereof.

[0069] In one embodiment, the phosphorus-containing antiwear agent can be a metal dialkyl dithiophosphate, which can include zinc dialkyl dithiophosphate. Such zinc salts are commonly referred to as zinc dialkyl dithiophosphate (ZDDP) or simply zinc dithiophosphate (ZDP). They are well known and readily available to those skilled in the art of lubricant formulations. Additionally, zinc dialkyl dithiophosphates can be described as primary zinc dialkyl dithiophosphates or secondary zinc dialkyl dithiophosphates, depending on the structure of the alcohol used in their preparation. In some embodiments, the present composition can include primary zinc dialkyl dithiophosphates. In some embodiments, the composition includes secondary zinc dialkyl dithiophosphates. In some embodiments, the composition includes a mixture of primary zinc dialkyl dithiophosphates and secondary zinc dialkyl dithiophosphates. In some embodiments, component (b) is a mixture of primary zinc dialkyldithiophosphate and secondary zinc dialkyldithiophosphate, wherein the ratio of primary zinc dialkyldithiophosphate to secondary zinc dialkyldithiophosphate (on a weight basis) is at least 1:1 or even at least 1:1.2 or even at least 1:1.5 or 1:2 or 1:10.

[0070] Examples of suitable dialkyldithiometallate phosphates include metal salts of the formula:

[0071]

[0072] where R 1 and R 2 is independently a hydrocarbyl group containing 3 to 24 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms; M is a metal having a valence of n, and typically includes zinc, copper, iron, cobalt, antimony, manganese, and combinations thereof. In one embodiment, R 1 and R 2 is a secondary aliphatic hydrocarbyl group containing from 3 to 8 carbon atoms, and M is zinc.

[0073] In one embodiment, the phosphorus-containing antiwear agent can be a zinc-free phosphorus-containing compound. The zinc-free phosphorus antiwear agent can contain sulfur or can be sulfur-free. The sulfur-free phosphorus antiwear agent includes a hydrocarbyl phosphite, a hydrocarbyl phosphine, a hydrocarbyl phosphonate, an alkyl phosphate, an amine or ammonium phosphate, or a mixture thereof.

[0074] In one embodiment, the phosphorus-containing antiwear agent is present in the lubricating composition in an amount to deliver 300 ppm to 900 ppm phosphorus to the lubricating composition. In one embodiment, the antiwear agent is ZDDP and is present in the composition in an amount to deliver 400 ppm to 850 ppm, or 450 ppm to 800 ppm, or 500 ppm to 800 ppm, or 550 ppm to 780 ppm, or 650 ppm to 780 ppm phosphorus to the lubricating composition.

[0075] In one embodiment, the phosphorus-containing antiwear agent is present in an amount from 0.2 wt % to 2 wt %, or from 0.3 wt % to 1.3 wt %, or from 0.5 wt % to 0.95 wt % of the lubricant composition.

[0076] Other performance additives

[0077] The lubricating composition can be prepared by blending an oil of lubricating viscosity, a first PIB succinimide dispersant, a second succinimide dispersant, a calcium salicylate detergent, an alkaline earth metal detergent, a phosphorus antiwear agent, and optionally one or more performance additives (as described below).

[0078] Other performance additives include at least one of metal deactivators, viscosity modifiers, friction modifiers, anti-wear agents, corrosion inhibitors, extreme pressure agents, antioxidants, foam inhibitors, demulsifiers, pour point depressants, seal swell agents, and mixtures thereof. Typically, a fully formulated lubricating oil will contain one or more of these performance additives.

[0079] In another embodiment, the lubricating composition comprises an antioxidant, wherein the antioxidant comprises a phenolic antioxidant, an aminic antioxidant, or a mixture thereof. The antioxidant comprises a diarylamine, an alkylated diarylamine, a hindered phenol, or a mixture thereof. When present, each antioxidant is independently present in an amount of 0.1% to 3% by weight, 0.5% to 2.75% by weight, or 1% to 2.5% by weight of the lubricating composition.

[0080] Diarylamine or alkylated diarylamine can be phenyl-α-naphthylamine (PANA), alkylated diphenylamine or alkylated phenylnaphthylamine or their mixture.Alkylated diphenylamine can include dinonylated diphenylamine, nonyldiphenylamine, octyldiphenylamine, dioctylated diphenylamine, didecylized diphenylamine, decyldiphenylamine and their mixture.In one embodiment, diphenylamine can include nonyldiphenylamine, dinonyldiphenylamine, octyldiphenylamine, dioctyldiphenylamine or their mixture.In another embodiment, alkylated diphenylamine can include nonyldiphenylamine or dinonyldiphenylamine.Alkylated diarylamine can include octyl, dioctyl, nonyl, dinonyl, decyl or didecylphenylnaphthylamine.

[0081] Hindered phenol antioxidants typically contain sec-butyl and / or t-butyl groups as steric hindering groups. The phenol group may typically be further substituted with a hydrocarbyl group (typically a linear or branched alkyl group) and / or a bridging group to a second aromatic group. Examples of suitable hindered phenol antioxidants include 2,6-di-t-butylphenol, 4-methyl-2,6-di-t-butylphenol, 4-ethyl-2,6-di-t-butylphenol, 4-propyl-2,6-di-t-butylphenol or 4-butyl-2,6-di-t-butylphenol or 4-dodecyl-2,6-di-t-butylphenol. In one embodiment, the hindered phenol antioxidant may be an ester and may include, for example, Irganox available from Ciba. TM L-135. Suitable hindered phenol esters include hydrocarbyl esters of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid, such as hydrocarbyl esters containing 3 to 18 carbon atoms, or 4 to 12 carbon atoms, or 6 to 10 carbon atoms. A more detailed description of suitable ester-containing hindered phenol antioxidant chemistry is found in U.S. Patent 6,559,105.

[0082] In one embodiment, the lubricating composition contains a friction modifier. The friction modifier can be selected from the group consisting of long-chain fatty acid derivatives of amines, long-chain fatty esters, or long-chain fatty epoxide derivatives; fatty imidazolines; amine salts of alkyl phosphoric acids; fatty alkyl tartaric acid esters; fatty alkyl tartarimides; fatty alkyl tartaramides; fatty glycolates; fatty glycolamides; and combinations thereof.

[0083] As used herein, the term "fatty alkyl" or "fat" in relation to friction modifiers refers to a carbon chain, typically a straight carbon chain, having from 10 to 24 carbon atoms, which may be saturated or unsaturated.

[0084] Examples of suitable friction modifiers include long chain fatty acid derivatives of amines, fatty acid esters or fatty epoxides; fatty imidazolines, such as condensation products of carboxylic acids and polyalkylene polyamines; amine salts of alkyl phosphoric acids; fatty alkyl tartaric acids; fatty alkyl tartarimides; fatty alkyl tartaramides; fatty phosphonates; fatty phosphites; borated phospholipids, borated fatty epoxides; glycerides; borated glycerides; fatty amines; alkoxylated fatty amines; borated alkoxylated fatty amines; hydroxy and polyhydroxy fatty amines, including tertiary hydroxy fatty amines; hydroxyalkyl amides; metal salts of fatty acids; metal salts of alkyl salicylates; fatty acids; oxazoline; fatty ethoxylated alcohols; condensation products of carboxylic acids and polyalkylene polyamines; or reaction products of fatty carboxylic acids with guanidine, aminoguanidine, urea or thiourea and their salts.

[0085] Friction modifiers may also include materials such as sulfurized aliphatic compounds and olefins, molybdenum compounds such as molybdenum dialkyl dithiophosphates, molybdenum dithiocarbamates, amine-salted molybdic acid compounds, and molybdenum post-treated succinimide dispersants. The molybdenum dithiocarbamates may be mononuclear, dinuclear, or even trinuclear complexes. Suitable molybdenum compounds may be present as Mo(IV) complexes, Mo(V) complexes, or Mo(VI) complexes, or combinations thereof, and include commercial materials such as Sakura-lube 525 from Adeka Co. Ltd. and Sakura-lube 525 from Vanderbilt Chemicals LLC. 855.

[0086] In another embodiment, the friction modifier can be a long chain fatty acid ester. In another embodiment, the long chain fatty acid ester can be a monoester, and in another embodiment, the long chain fatty acid ester can be a triglyceride. Suitable triglycerides include vegetable oils, such as soybean oil or sunflower oil.

[0087] The ashless friction modifier may be present in the lubricating composition in an amount from 0.01 wt % to 2.5 wt %, or from 0.1 wt % to 0.5 wt %, or from 0.3 wt % to 2.0 wt %, or from 0.5 wt % to 0.9 wt %.

[0088] Lubricating composition also optionally comprises at least one antiwear agent except above-mentioned phosphorus-containing antiwear agent.The example of suitable antiwear agent comprises titanium compound, tartrate, tartrimide, the compound containing thiocarbamate, such as thiocarbamate, thiocarbamate amide, thiocarbamate ether, alkylene coupling thiocarbamate and bis(S-alkyl dithiocarbamoyl) disulfide.In one embodiment, antiwear agent can comprise tartrate or tartrimide, as disclosed in international publication WO 2006 / 044411 or Canadian patent CA 1 183 125.Tartrate or tartrimide can contain alkyl-ester group, and wherein the sum of carbon atoms on the alkyl group is at least 8.In one embodiment, antiwear agent can comprise citrate, as disclosed in U.S. Patent Application 20050198894.

[0089] Another class of additives includes oil-soluble titanium compounds, such as disclosed in US 7,727,943 and US2006 / 0014651. The oil-soluble titanium compound can be used as an anti-wear agent, a friction modifier, an antioxidant, a deposit control additive, or more than one of these functions. In one embodiment, the oil-soluble titanium compound is a titanium (IV) alkoxide. The titanium alkoxide is formed from the following substances: a monohydric alcohol, a polyhydric alcohol, or a mixture thereof. The monohydric alkoxide can have 2 to 16 carbon atoms or 3 to 10 carbon atoms. In one embodiment, the titanium alkoxide is titanium (IV) isopropoxide. In one embodiment, the titanium alkoxide is titanium (IV) 2-ethylhexyl alcohol. In one embodiment, the titanium compound includes an alkoxide of an adjacent 1,2-diol or a polyol. In one embodiment, the 1,2-vicinal diol includes a fatty acid monoester of glycerol, typically the fatty acid is oleic acid.

[0090] In one embodiment, the oil-soluble titanium compound is a titanium carboxylate. In another embodiment, the titanium (IV) carboxylate is titanium neodecanoate.

[0091] Extreme pressure (EP) agents soluble in oil include sulfur-containing and chlorinated sulfur-containing EP agents, dimercaptothiadiazole or CS2 derivatives of dispersants (typically succinimide dispersants), chlorinated hydrocarbon EP agents, and derivatives of phosphorus EP agents. Examples of such EP agents include chlorinated waxes; sulfurized olefins (such as sulfurized isobutylene), hydrocarbon-substituted 2,5-dimercapto-1,3,4-thiadiazoles or oligomers thereof, organic sulfides and polysulfides (such as dibenzyl disulfide, bis-(chlorobenzyl) disulfide, dibutyl tetrasulfide), sulfurized methyl oleate, sulfurized alkylphenols, sulfurized dipentenes, sulfurized terpenes, and sulfurized Diels-Alder adducts; phosphorus sulfurized hydrocarbons, such as the reaction products of phosphorus sulfide with turpentine or methyl oleate; phosphites, such as di- and tri-hydrocarbon phosphites, for example, Dibutyl phosphate, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite; dipentylphenyl phosphite, tridecyl phosphite, distearyl phosphite and polypropylene-substituted phenol phosphites; metal thiocarbamates, such as zinc dioctyldithiocarbamate and barium heptylphenol dioate; amine salts or derivatives of alkyl and dialkyl phosphoric acids, including, for example, amine salts of the product of the reaction of a dialkyldithiophosphoric acid with propylene oxide and subsequent further reaction with P2O5; and mixtures thereof (as described in US 3,197,405).

[0092] Foam suppressors that may be used in the present compositions include silicones, copolymers of ethyl acrylate and 2-ethylhexyl acrylate, and optionally vinyl acetate; demulsifiers include fluorinated silicones, trialkyl phosphates, polyethylene glycols, polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers.

[0093] Polymeric viscosity index improvers (also referred to as viscosity modifiers (VM) or dispersant viscosity modifiers (DVM)) can be used in the compositions disclosed herein. Dispersant viscosity modifiers are generally understood to be functionalized (i.e., derivatized) forms of polymers similar to polymeric viscosity modifiers. The polymeric viscosity modifier can be an olefin (co)polymer, a poly (meth)acrylate (PMA), or a mixture thereof. In one embodiment, the polymeric viscosity modifier is an olefin (co)polymer or a dispersant viscosity modifier derived therefrom.

[0094] The olefin polymer can be derived from isobutylene or isoprene. In one embodiment, the olefin polymer is prepared from ethylene and a higher olefin in the C3-C10 alpha-monoolefin range, for example, the olefin polymer can be prepared from ethylene and propylene.

[0095] Useful olefin polymers, particularly ethylene-α-olefin copolymers, have a number average molecular weight of 4500 to 500000 (e.g., 5000 to 100,000 or 7500 to 60000 or 8000 to 45000).

[0096] The formation of functionalized ethylene-α-olefin copolymers is well known in the art, for example, those described in U.S. Patent No. 7,790,661 at column 2, line 48 to column 10, line 38. Additional detailed descriptions of similar functionalized ethylene-α-olefin copolymers can be found in International Publication No. WO 2006 / 015130 or U.S. Patent Nos. 4,863,623, 6,107,257, 6,107,258, 6,117,825, and U.S. Patent No. 7,790,661. In one embodiment, the functionalized ethylene-α-olefin copolymers can include those described in U.S. Patent No. 4,863,623 (see column 2, line 15 to column 3, line 52) or International Publication No. WO 2006 / 015130 (see page 2, paragraph

[0008] and the preparation examples described in paragraphs

[0065] to

[0073] ).

[0097] In one embodiment, the lubricating composition comprises a dispersant viscosity modifier (DVM).The DVM may comprise an olefin polymer that has been modified by the addition of a polar moiety.

[0098] Olefin polymers are functionalized by modifying the polymer by adding a polar moiety. In a useful embodiment, the functionalized copolymer is the reaction product of an olefin polymer grafted with an acylating agent. In one embodiment, the acylating agent can be an ethylenically unsaturated acylating agent. Useful acylating agents are generally αβ-unsaturated compounds having at least one olefinic bond (before the reaction) and at least one (e.g., two) carboxylic acid (or its anhydride) group or a polar group that can be converted into the carboxyl group by oxidation or hydrolysis. The acylating agent is grafted onto the olefin polymer to obtain two carboxylic acid functional groups. Examples of useful acylating agents include maleic anhydride, chloromaleic anhydride, itaconic anhydride or their reactive equivalents, for example, corresponding dicarboxylic acids such as maleic acid, fumaric acid, cinnamic acid, (meth) acrylic acid, esters of these compounds and acyl chlorides of these compounds.

[0099] In one embodiment, the functionalized ethylene-α-olefin copolymer comprises an olefin copolymer grafted with acyl groups, which is further functionalized with hydrocarbyl amines, hydrocarbyl alcohol groups, amino- or hydroxy-terminated polyether compounds, and mixtures thereof.

[0100] In one embodiment, the hydrocarbyl amine may be selected from aromatic amines, aliphatic amines, and mixtures thereof. In one embodiment, the hydrocarbyl amine component may comprise at least one aromatic amine containing at least one amino group capable of condensing with the acyl group to provide a pendant group and at least one additional group containing at least one nitrogen, oxygen, or sulfur atom, wherein the aromatic amine is selected from the group consisting of: (i) nitro-substituted aniline; (ii) an amine comprising two aromatic moieties linked by a C(O)NR- group, a -C(O)O- group, an -O- group, an N=N- group, or a -SO2- group, wherein R is hydrogen or a hydrocarbyl group, one of the aromatic moieties bearing the condensable amino group; (iii) aminoquinoline; (iv) aminobenzimidazole; (v) N,N-dialkylphenylenediamine; (vi) aminodiphenylamine (also known as N-phenylphenylenediamine); (vii) ring-substituted benzylamine; and (viii) methylene-bonded dimers of aminodiphenylamine.

[0101] In one embodiment, the lubricating composition may comprise a poly(meth)acrylate polymer viscosity modifier.As used herein, the term "(meth)acrylate" and its cognates refer to methacrylate or acrylate, as will be readily understood.

[0102] In one embodiment, the poly(meth)acrylate polymer is prepared from a monomer mixture comprising (meth)acrylate monomers having alkyl groups of varying lengths. The (meth)acrylate monomers may contain alkyl groups that are linear or branched. The alkyl groups may contain from 1 to 24 carbon atoms, for example, from 1 to 20 carbon atoms.

[0103] In one embodiment, the poly(meth)acrylate polymer comprises a dispersant monomer; dispersant monomers include those monomers copolymerizable with the (meth)acrylate monomer and containing one or more heteroatoms in addition to the carbonyl group of the (meth)acrylate. The dispersant monomer may contain nitrogen-containing groups, oxygen-containing groups, or mixtures thereof.

[0104] The dispersant monomer may be present in an amount of up to 5 mol% of the monomer composition of the (meth)acrylate polymer. In one embodiment, the poly(meth)acrylate is present in an amount of 0 mol% to 5 mol%, 0.5 mol% to 4 mol%, or 0.8 mol% to 3 mol% of the polymer composition. In one embodiment, the poly(meth)acrylate is free or substantially free of dispersant monomer.

[0105] In one embodiment, the poly(meth)acrylate polymer (P) is a block or tapered block copolymer comprising at least one polymer block (Bi) that is insoluble or substantially insoluble in a base oil and a second polymer block (B2) that is soluble or substantially soluble in a base oil.

[0106] In one embodiment, the poly (meth) acrylate polymer can have a structure selected from linear, branched, hyperbranched, cross-linked, star-shaped (also referred to as "radial"), or a combination thereof. Star-shaped or radial refers to a multi-arm polymer. Such polymers include polymers containing (meth) acrylates comprising 3 or more arms or branches, and in some embodiments, contain at least about 20 or at least 50 or 100 or 200 or 350 or 500 or 1,000 carbon atoms. The arms are typically connected to a multivalent organic portion acting as a "core" or "coupling agent." Multi-arm polymers can be referred to as radial or star-shaped polymers or even "comb-shaped" polymers or polymers otherwise having multiple arms or branches as described herein.

[0107] Random, block or other forms of linear poly (meth) acrylate can have a weight average molecular weight (Mw) of 1,000 dalton to 400,000 dalton, 1,000 dalton to 150,000 dalton or 15,000 dalton to 100,000 dalton. In one embodiment, poly (meth) acrylate can be a linear block copolymer with an Mw of 5000 dalton to 40000 dalton or 10,000 dalton to 30000 dalton. Radial, cross-linked or star copolymers can be derived from linear random or diblock copolymers with molecular weights as described above. Star polymers can have a weight average molecular weight of 10,000 dalton to 1,500,000 dalton, 40,000 dalton to 1,000,000 dalton, 300,000 to 850,000 dalton.

[0108] Another class of polymeric viscosity modifiers are styrene-diene (SD) copolymers, such as styrene isoprene (SI) and styrene butadiene (SBR). Styrene-diene copolymers can be linear or radial (star-shaped) and typically contain one or more different blocks of styrene attached to one or more different blocks of hydrogenated diene.

[0109] The lubricating composition may comprise 0.05 wt % to 2 wt % or 0.08 wt % to 1.2 wt % or 0.1 wt % to 0.8 wt % of one or more polymeric viscosity modifiers and / or dispersant viscosity modifiers.

[0110] Pour point depressants that may be used in the compositions disclosed herein include poly-alpha-olefins, esters of maleic anhydride-styrene copolymers, poly(meth)acrylates, polyacrylates, or polyacrylamides.

[0111] Demulsifiers include trialkyl phosphates, and various polymers and copolymers of ethylene glycol, ethylene oxide, propylene oxide, or mixtures thereof.

[0112] Metal passivators include derivatives of benzotriazole (typically tolyltriazole), 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, or 2-alkyldithiobenzothiazole. Metal passivators can also be described as etch resists.

[0113] Seal swell agents include the diolefin sulfone derivative Exxon Necton-37 TM (FN 1380) and Exxon MineralSeal Oil TM (FN 3200).

[0114] The lubricating composition may further comprise one or more dispersants other than the first and second PIB succinimide dispersants of the compositions disclosed herein. Such dispersants include dispersants other than the succinimide dispersants of the compositions, Mannich dispersants, polyolefin succinates, amides, or ester-amides, or mixtures thereof.

[0115] The additional dispersant may be a PIB succinimide similar to the dispersant of the composition, derived from polyisobutylene having a number average molecular weight of 800 to 2,600 Daltons. The additional dispersant may be present to provide a boost to soot handling or as a source of ashless TBN. The soot dispersant may be functionalized with an aromatic (poly)amine. Dispersants used as TBN boosters typically have a high TBN, such as greater than 80 mg KOH / g, greater than 95 mg KOH / g, or even greater than 110 mg KOH / g.

[0116] The additional dispersant may be present in an amount from 0.05 wt % to 2 wt %, or from 0.1 wt % to 1.1 wt %, or from 0.2 wt % to 0.8 wt % of the lubricant composition.

[0117] Industrial Applications

[0118] The lubricating compositions disclosed herein are suitable for use in diesel engines. Diesel engines are classified by their Gross Vehicle Weight Rating (GVWR). The GVWR includes the maximum rated weight of the vehicle and cargo (including passengers). The GVWR applies to either the truck or the trailer, but not the combination of the two, which is a separate rating called the Gross Combination Weight Rating (GCWR). The GVWRs for various diesel engine types are listed in the following table:

[0119]

[0120] Light-duty vehicles are classified as those belonging to Classes 1 through 3. Class 2A vehicles are often referred to as "light-duty" vehicles, and Class 2B vehicles are often referred to as "light-heavy-duty" vehicles.

[0121] Medium-duty vehicles are those belonging to classes 4 to 6. Heavy-duty vehicles are those classified as classes 7 and 8.

[0122] There are significant differences between vehicle categories because they involve operating conditions. The difference in size means that higher-class vehicles have engines that will experience significantly different operating conditions (such as load, oil temperature, duty cycle, and engine speed). Heavy-duty diesel engines are designed to maximize the torque used to tow a payload with maximum fuel economy, while passenger cars (lower-class vehicles) are designed to carry people for commuting and acceleration with maximum fuel economy. The design purpose of engine traction and commuting leads to different hardware designs and causes stress on the lubricants designed to protect and lubricate the engine. Another significant design difference is the revolutions per minute (RPM), with which each engine operates for traction and commuting. Heavy-duty diesel engines (such as typical 12-13 liter truck engines) typically do not exceed 2200rpm, while passenger car engines can reach 4500rpm.

[0123] In one embodiment, the internal combustion engine is a heavy duty diesel compression ignition (or spark assisted compression ignition) internal combustion engine.

[0124] The sulfur content of the lubricating composition may be 1% by weight or less, or 0.8% by weight or less, or 0.5% by weight or less, or 0.3% by weight or less. In one embodiment, the sulfur content may be in the range of 0.001% by weight to 0.5% by weight, or 0.01% by weight to 0.3% by weight. The phosphorus content may be 0.2% by weight or less, or 0.12% by weight or less, or 0.1% by weight or less, or 0.085% by weight or less, or 0.08% by weight or less, or even 0.06% by weight or less, 0.055% by weight or less, or 0.05% by weight or less. In one embodiment, the phosphorus content may be 0.04% by weight to 0.12% by weight. In one embodiment, the phosphorus content may be 100 ppm to 1000 ppm, or 200 ppm to 600 ppm. The total sulfated ash content may be 0.3% to 1.2% by weight, or 0.5% to 1.1% by weight of the lubricating composition.

[0125] In one embodiment, the sulfated ash content may be from 0.2 wt % to 1.2 wt % of the lubricating composition. The lubricating compositions disclosed herein may have a sulfated ash content of from 0.2 wt % to 1.2 wt % or from 0.3 wt % to 1.1 wt % or from 0.4 wt % to 0.8 wt %.

[0126] As used herein, TBN value (Total Base Number) is measured by the method described in ASTM D4739 (buffer).

[0127] The lubricating composition may be characterized as having a total base number (TBN) content of at least 3 mg KOH / g, or at least 4 mg KOH / g, or at least 5 mg KOH / g.

[0128] The lubricating composition may be characterized as having a total base number (TBN) content of 5 mg KOH / g to 10 mg KOH / g or 5 mg KOH / g to 8.5 mg KOH / g.

[0129] The lubricating compositions disclosed herein have a hardness of 2.5 cSt to 8.3 cSt or 3.5 cSt to 6.5 cSt (mm) at 100°C as measured by ASTM D-445. 2 / s) and 15 cSt to 30 cSt (mm at 40 °C 2 In another embodiment, the lubricating composition has a kinematic viscosity of 2.5 cSt to 6.5 cSt or 3 cSt to 5.5 cSt (mm) at 100°C. 2 / s) and 15 cSt to 25 cSt (mm at 40 °C 2 / s) in kinematic viscosity.

[0130] The lubricating compositions disclosed herein have a high temperature high shear viscosity (HTHS) of less than 2.6 mPa-s, or less than 2.5 mPa-s, or less than 2.3 mPa-s, or less than 2.1 mPa-s at 150° C. as measured by ASTM D4683. In another embodiment, the lubricating composition has a HTHS of from 1.4 mPa-s to 2.5 mPa-s, or from 1.6 mPa-s to 2.1 mPa-s, or from 1.8 mPa-s to 2.1 mPa-s, or from 1.9 mPa-s to 2.0 mPa-s.

[0131] The lubricating composition may have an SAE viscosity grade of 0W-Y, where Y may be 12, 16, or 20. In one embodiment, the lubricating composition has an SAE viscosity grade of 0W-12.

[0132] The internal combustion engines disclosed herein may have steel surfaces on the cylinder bores, cylinder blocks, or piston rings.

[0133] The internal combustion engine may have a surface of steel or an aluminum alloy or an aluminum composite material.

[0134] Typically, a compression ignition internal combustion engine has a maximum load mass exceeding 3,500 kg.

[0135] The present disclosure also relates to a method of lubricating a diesel engine by supplying to the engine any of the lubricating compositions disclosed herein. In one embodiment, the method comprises lubricating the diesel engine by supplying to the engine a lubricating composition having: an oil of lubricating viscosity having greater than 50% by weight of a Group III base oil, a Group IV base oil, or a mixture thereof; a first PIB succinimide dispersant derived from 1800 Mn to 2500 Mn; PIB; a second PIB succinimide dispersant derived from PIB having an Mn of less than 1600, wherein at least one of the first PIB succinimide dispersant and the second PIB succinimide dispersant is free of boron; a calcium salicylate detergent; an alkaline earth metal sulfonate detergent, the alkaline earth metal sulfonate detergent being present in an amount to deliver 0.3 wt % to 2.1 wt % alkaline earth metal soap to the lubricating composition; and a phosphorus antiwear agent being present in an amount to deliver 300 ppm to 900 ppm phosphorus to the lubricating composition, wherein the lubricating composition further comprises between 0.3 wt % and 0.9 wt % total sulfated ash and a HTHS of less than 2.7 mPa.s as measured according to ASTM D4683.

[0136] Another embodiment provides the use of any of the lubricating compositions disclosed herein to improve at least one of wear protection and fuel economy of a compression-ignition internal combustion engine, typically a heavy-duty diesel internal combustion engine.

[0137] In various embodiments, the lubricating compositions disclosed herein may have the compositions described in the following table:

[0138]

[0139] The following examples provide illustrations of the compositions. These examples are non-exhaustive and are not intended to limit the scope of the invention.

[0140] Example

[0141] A series of 0W-12 engine lubricants in a Group III base oil of lubricating viscosity were prepared containing the above additives as well as conventional additives including polymeric viscosity modifiers, corrosion inhibitors, pour point depressants, and other performance additives as follows (Table 1). Elements are included to demonstrate the relative equivalence of the compositions.

[0142] Table 1 - Lubricating Compositions 1

[0143]

[0144]

[0145] 1. Unless otherwise stated, all treatment rates presented are without oil

[0146] 2. Polyisobutylene succinimide dispersant prepared from 2300Mn low vinylidene PIB via the Diels-Alder process (TBN 54 mg KOH / g)

[0147] 3. Borated analogs of the above dispersants (1 wt% boron)

[0148] 4.PIB succinimide aromatic amine soot dispersant

[0149] 5. Polyisobutylene succinimide dispersant prepared from high vinylidene 2000Mn PIB via thermal olefin alkylation (TBN 26 mg KOH / g)

[0150] 6. Polyisobutylene succinimide dispersant prepared from 980Mn PIB (TBN 25 mg KOH / g)

[0151] 7. Polyisobutylene succinimide dispersant prepared from high vinylidene 1550Mn PIB via thermal olefin alkylation (TBN 17 mg KOH / g)

[0152] 8. Overbased calcium alkylbenzene sulfonate (TBN 520 mg KOH / g; 48% substrate)

[0153] 9. Overbased calcium alkyl salicylate detergent (TBN 300 mg KOH / g; metal ratio 2.8)

[0154] 10. Low TBN calcium alkylbenzene sulfonate detergent (TBN 170 mg KOH / g; 84% substrate; metal ratio 2.7)

[0155] 11. Combinations of diarylamines, hindered phenols and sulphurised olefins.

[0156] 12. Combination of low Mn (10 kDa) and high Mn (60 kDa) substituted ethylene-propylene copolymers functionalized with aromatic amines

[0157] 13. Premix of oleyl tartarimide (44 wt %), boronating agent, basic nitrogen, and compatibilizer (0.46 wt % boron; TBN 17 mg KOH / g)

[0158] 14. Sulfur-bridged molybdenum (V) dimer, dithiocarbamate complex (commercially available as Sakurolube 525 from Adeka)

[0159] 15. Other additives include pour point depressants, foam inhibitors and low levels of corrosion inhibitors and compatibilizers.

[0160] The lubricating examples of Table 1 were evaluated for fuel economy improvement and wear prevention / reduction capabilities. The results are summarized along with other chemical and physical properties relevant to performance (Table 2). Fuel economy improvement was measured according to the Volvo D13TC fuel economy test. In this test, improvement is determined relative to a preselected reference oil; in these data, Example 8 (EX8) was selected as the reference oil.

[0161] Wear resistance (also known as durability) was measured on a high frequency reciprocating tester (HFRR) available from PCS Instruments. The HFRR conditions used for evaluation were 500 g load, 75 minutes duration, 1000 micron stroke, 20 Hz frequency, and a temperature of 105° C. Wear and contact potential were then measured.

[0162] Table 2

[0163]

[0164] The results obtained demonstrate that the lubricant composition can provide improved fuel economy while maintaining or even enhancing wear control.

[0165] The lubricant compositions described herein also provide cleanliness, deposit control, and oxidation control in suitable bench tests. Deposition performance can be measured according to the Thermal Oxidation Engine Oil Simulation Test (TEOST 33) as set forth in ASTM D6335. The results of the TEOST 33 test show the number of milligrams deposited after the engine oil is run at elevated temperatures. Lower TEOST 33 results indicate improved resistance to deposit formation. The deposit control of the lubricating composition can be tested in a Panel Cooker heated to 325°C, with a sump temperature of 105°C and a splash / bake cycle of 120s / 45s. The air flow rate is 350ml / min, the spindle speed is 1000rpm, and the test lasts for 4 hours. The oil is sprayed onto aluminum panels and then optically evaluated by a computer. Performance ranges from 0% (black panel) to 100% (clean panel).

[0166] The fuel economy of the disclosed lubricating compositions can be tested and can be improved according to any of the M111 fuel economy test (CEC L-54-96), the Daimler OM501LA fuel economy test, the NEDC MB fuel economy test, and the ILSAC sequence VI engine test. Friction performance can also be evaluated in any of several high frequency reciprocating test machine (HFRR) bench tests (e.g., ASTM D6079).

[0167] Unless otherwise indicated herein, all references to treat rates or amounts of components present in the lubricating compositions disclosed herein are on an oil-free basis, ie, active matter amount.

[0168] As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, which is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character, including one or more double bonds. Examples of hydrocarbyl groups include: hydrocarbyl substituents, i.e., aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic, aliphatic, and alicyclic substituted aromatic substituents, as well as cyclic substituents in which the ring is completed by another part of the molecule (e.g., two substituents together form a ring); substituted hydrocarbyl substituents, i.e., substituents containing non-hydrocarbon groups which, in the context of the present invention, do not alter the predominantly hydrocarbon nature of the substituent (e.g., halogens (particularly chlorine and fluorine), hydroxyl, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxyl); heterosubstituents, i.e., substituents having predominantly hydrocarbon character in the context of the present invention, but containing atoms other than carbon in a ring or chain consisting of, such as pyridyl, furyl, thienyl, and imidazolyl. Heteroatoms include sulfur, oxygen, and nitrogen. Typically, no more than two, or no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; alternatively, there may be no non-hydrocarbon substituents in the hydrocarbyl group.

[0169] The present disclosure is not limited to the specific embodiments described in this application, and these embodiments are intended to illustrate various aspects. Without departing from the spirit and scope of the present invention, many modifications and variations can be made, which will be apparent to those skilled in the art. In addition to those listed herein, functionally equivalent methods and components within the scope of the present disclosure will be apparent to those skilled in the art based on the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is only subject to the terms of the appended claims and the full scope of equivalents granted by such claims. It should be understood that the present disclosure is not limited to specific methods, reagents, compounds or compositions, which can certainly vary. It should also be understood that the terms used herein are only used to describe the purpose of specific embodiments and are not intended to be limiting.

[0170] As used in this document, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Nothing in this disclosure should be construed as an admission that the embodiments described in this disclosure are not entitled to antedate this disclosure by virtue of prior invention. As used herein, the term "including" means "including, but not limited to."

[0171] Although various compositions, methods, and apparatus are described as "comprising" various components or steps (interpreted to mean "including, but not limited to"), the compositions, methods, and apparatus may also be described as "consisting essentially of" or "consisting of" the various components and steps, and such terms should be interpreted as limiting a substantially closed group of members.

[0172] With respect to the use of substantially any plural and / or singular terms herein, those skilled in the art can translate from the plural to the singular and / or from the singular to the plural as appropriate, depending on the context and / or application. For clarity, various singular / plural arrangements may be explicitly set forth herein.

[0173] Those skilled in the art will understand that, in general, the terms used herein and in particular in the appended claims (e.g., the bodies of the appended claims) are generally intended to be “open” terms (e.g., the term “including” should be interpreted as “including, but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “including, but not limited to,” etc.). Those skilled in the art will further understand that if a specific number of introduced claim statements is intended, such intent will be expressly stated in the claim, and in the absence of such statement, no such intent is present. For example, to aid understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim statements. However, the use of such phrases should not be interpreted as implying that introducing a claim recitation by the indefinite article "a," "an" limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and an indefinite article such as "a," "an" (e.g., "a," "an" should be interpreted as meaning "at least one" or "one or more"); the same is true for the use of definite articles to introduce claim recitations. In addition, even if a specific number of introduced claim recitations is expressly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the unmodified recitation "two recitations," without other modifiers, means at least two recitations or two or more recitations). Furthermore, in those instances where a convention similar to “at least one of A, B, and C, etc.” is used, generally speaking, such construction is intended to have a meaning that one skilled in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include, but is not limited to, systems having only A, only B, only C, A and B, A and C, B and C, and / or A, B, and C, etc.). In those instances where a convention similar to “at least one of A, B, or C, etc.” is used, generally speaking, such construction is intended to have a meaning that one skilled in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include, but is not limited to, systems having only A, only B, only C, A and B, A and C, B and C, and / or A, B, and C, etc.). Those skilled in the art will further understand that, whether in the specification, claims, or drawings, virtually any disjunctive word and / or phrase presenting two or more alternative terms should be understood to contemplate the possibility of including one, either, or both of the terms.For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

[0174] In addition, where features or aspects of the disclosure may be described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[0175] As will be understood by those skilled in the art, for any and all purposes, such as with respect to providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations thereof. Any listed range can easily be considered to fully describe and enable the same range to be decomposed into at least equal halves, thirds, quarters, fifths, tenths, etc. As non-limiting examples, each range discussed herein can easily be decomposed into lower thirds, middle thirds, and upper thirds, etc. As will be understood by those skilled in the art, all languages ​​(such as "at most," "at least," etc.) include the stated numbers and refer to ranges that can subsequently be decomposed into subranges as described above. Finally, as will be understood by those skilled in the art, ranges include each individual member. Therefore, for example, a group having 1% to 3% by weight refers to a group having 1%, 2%, or 3% by weight. Similarly, a group having 1% to 5% by weight refers to a group having 1%, 2%, 3%, 4%, or 5% by weight, etc., including all points therebetween.

[0176] Furthermore, when a stated range is provided for a treat rate, it is contemplated that the range should include treat rates for individual components and / or mixtures of components. Thus, for example, a range of 1 wt % to 3 wt % contemplates that a given component may be present in a range of 1 wt % to 3 wt % or that a mixture of similar components may be present in a range of 1 wt % to 3 wt %.

[0177] As used herein, the term "about" means that the value of a given amount is within ±20% of the stated value. In other embodiments, the value is within ±15% of the stated value. In other embodiments, the value is within ±10% of the stated value. In other embodiments, the value is within ±5% of the stated value. In other embodiments, the value is within ±2.5% of the stated value. In other embodiments, the value is within ±1% of the stated value.

[0178] Unless otherwise indicated, "wt %" as used herein shall refer to weight percent based on the total weight of the composition on an oil-free basis.

[0179] As described below, known methods (such as GPC analysis using polystyrene standards) have been used to determine the number average molecular weight of dispersant viscosity modifiers and viscosity modifiers. Methods for determining the molecular weight of polymers are well known. For example, these methods are described in: (i) PJ Flory, "Principles of Polymer Chemistry", Cornell University Press (1953), Chapter VII, pages 266 to 315; or (ii) "Macromolecules, an Introduction to Polymer Science", compiled by F.A. Bovey and F.H. Winslow, Academic Press (1979), pages 296 to 312.

[0180] Although the present invention has been explained with respect to its preferred embodiment, it will be appreciated that various modifications thereof will become apparent to those skilled in the art upon reading this specification. Therefore, it will be understood that the invention disclosed herein is intended to cover these modifications that fall within the scope of the appended claims.

Claims

1. A diesel engine lubricating composition, comprising: an oil of lubricating viscosity having greater than 50 weight percent of a Group III base oil, a Group IV base oil, a Group V base oil, or a mixture thereof; a first polyisobutylene (PIB) succinimide dispersant derived from PIB having a number average molecular weight of 1800 to 2100 and present in the lubricating composition in an amount of 0.8 wt % to 6 wt %; a second polyisobutylene (PIB) succinimide dispersant derived from PIB having an Mn of less than or equal to 1600, wherein at least one of the first PIB succinimide dispersant and the second PIB succinimide dispersant is free of boron; Alkaline earth metal salicylate detergents; an alkaline earth metal sulfonate detergent present in an amount to deliver 0.1 wt % to 1.2 wt % of alkaline earth metal soap to the lubricating composition; as well as a phosphorus antiwear agent present in an amount to deliver 300 ppm to 900 ppm phosphorus to the lubricating composition, The lubricating composition has: a total sulfated ash content between 0.3 wt% and 0.9 wt% as determined in accordance with ASTM D874; a kinematic viscosity at 100°C of less than 8.3 cSt as measured in accordance with ASTM D-445; 0.6 to 2.1 wt% total alkaline earth soaps and a HTHS of less than 2.7 mPa.s as measured according to ASTM D4683.

2. The composition of claim 1, wherein the first PIB succinimide dispersant has a TBN of 15 to 25 as measured according to ASTM D4739.

3. The composition of claim 1, wherein the first PIB succinimide dispersant has a TBN of 15 to 20 as measured according to ASTM D4739.

4. The composition of any one of claims 1 to 3, wherein the first PIB succinimide dispersant is present in the lubricating composition in an amount of 1 wt% to 5 wt%.

5. The composition of any one of claims 1 to 3, wherein the first PIB succinimide dispersant is present in the lubricating composition in an amount of 1.5 wt% to 5 wt%.

6. The composition of any one of claims 1 to 3, wherein the first PIB succinimide dispersant is prepared by a thermal direct alkylation process.

7. The composition of any one of claims 1 to 3, wherein the first PIB succinimide dispersant comprises a mixture of two dispersants.

8. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is derived from PIB having a number average molecular weight of 750 to 1600.

9. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is derived from PIB having a number average molecular weight of 1000 to 1600.

10. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is derived from PIB having a number average molecular weight of 1200 to 1600.

11. The composition of claim 8, wherein the second PIB succinimide dispersant is derived from PIB having a number average molecular weight of 800 to 1150.

12. The composition of claim 8, wherein the second PIB succinimide dispersant is derived from PIB having a number average molecular weight of 900 to 1100.

13. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is prepared by a thermal direct alkylation process.

14. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is present in the lubricating composition in an amount of 1 wt% to 5 wt%.

15. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is present in the lubricating composition in an amount of 1.5 wt% to 4.8 wt%.

16. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is present in the lubricating composition in an amount of 1.8 wt% to 4.6 wt%.

17. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant is present in the lubricating composition in an amount of 1.9 wt% to 4.6 wt%.

18. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant comprises 1 wt% to 5 wt% of a PIB succinimide dispersant derived from a PIB having an Mn of 900 to 1100 and 1 wt% to 5 wt% of a PIB succinimide dispersant derived from a PIB having an Mn of 1200 to 1600.

19. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant has a TBN of 20 to 35 as measured according to ASTM D4739.

20. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant has a TBN of 25 to 30 as measured according to ASTM D4739.

21. The composition of any one of claims 1 to 3, wherein the second PIB succinimide dispersant has a TBN of 27 to 28 as measured according to ASTM D4739.

22. The composition of any one of claims 1 to 3, wherein the first PIB succinimide dispersant is borated.

23. The composition of claim 22, wherein the second PIB succinimide dispersant is borated.

24. The composition of claim 23, wherein the first and second PIB succinimide dispersants are present in amounts to independently deliver 25 ppm to 400 ppm by weight of boron to the lubricating composition.

25. The composition of claim 23, wherein the first and second PIB succinimide dispersants are present in amounts to independently deliver 50 ppm to 200 ppm by weight of boron to the lubricating composition.

26. A composition according to any one of claims 1 to 3, wherein the alkaline earth metal salicylate detergent has a TBN of 200 to 575 measured according to ASTM D4739.

27. A composition according to any one of claims 1 to 3, wherein the alkaline earth metal salicylate detergent has a TBN of 200 to 500 as measured according to ASTM D4739.

28. A composition according to any one of claims 1 to 3, wherein the alkaline earth metal salicylate is a calcium salicylate detergent having a TBN of 250 to 350 as measured according to ASTM D4739.

29. A composition according to any one of claims 1 to 3 wherein the alkaline earth metal salicylate detergent has a metal ratio of 2 to 7.

30. A composition according to any one of claims 1 to 3 wherein the alkaline earth metal salicylate detergent has a metal ratio of 2 to 4.

31. A composition according to any one of claims 1 to 3 wherein the alkaline earth metal salicylate detergent has a metal ratio of from 2.5 to 3.

5.

32. The composition of any one of claims 1 to 3, wherein the alkaline earth metal sulfonate detergent is selected from calcium sulfonate detergents and magnesium sulfonate detergents.

33. The composition of any one of claims 1 to 3, wherein the alkaline earth metal sulfonate detergent is a calcium sulfonate detergent.

34. The composition of claim 33, wherein the calcium sulfonate detergent has a TBN of less than 200 as measured according to ASTM D4739.

35. The composition of claim 33, wherein the calcium sulfonate detergent has a TBN of less than 150 as measured according to ASTM D4739.

36. The composition of claim 33, wherein the calcium sulfonate detergent has a TBN of less than 100 as measured according to ASTM D4739.

37. The composition of claim 33, wherein the calcium sulfonate detergent has a TBN of less than 80 as measured according to ASTM D4739.

38. The composition of claim 33, wherein the calcium sulfonate detergent has a TBN of 50 to 90 as measured according to ASTM D4739.

39. The composition of claim 33, wherein the calcium sulfonate detergent is present in the lubricant composition in an amount of 0.5% to 2.0% by weight.

40. The composition of claim 33, wherein the calcium sulfonate detergent is present in the lubricant composition in an amount of 0.6% to 1.5% by weight.

41. The composition of claim 38, wherein the calcium sulfonate detergent is present in the lubricant composition in an amount of 0.5% to 2.0% by weight.

42. The composition of claim 38, wherein the calcium sulfonate detergent is present in the lubricant composition in an amount of 0.6% to 1.5% by weight.

43. The composition of any one of claims 1 to 3, wherein the alkaline earth metal sulfonate detergent is an overbased magnesium sulfonate detergent.

44. The composition of claim 43, wherein the overbased magnesium sulfonate detergent has a TBN of 200 to 500 as measured according to ASTM D4739.

45. The composition of claim 43, wherein the overbased magnesium sulfonate detergent has a TBN of 250 to 400 as measured according to ASTM D4739.

46. ​​The composition of claim 43, wherein the overbased magnesium sulfonate detergent has a TBN of 250 to 350 as measured according to ASTM D4739.

47. The composition of claim 43, wherein the overbased magnesium sulfonate detergent has a TBN of 350 to 375 as measured according to ASTM D4739.

48. The composition of claim 43, wherein the overbased magnesium sulfonate detergent is present in the lubricating composition in an amount of 0.05 wt. % to 0.2 wt. %.

49. The composition of claim 43, wherein the overbased magnesium sulfonate detergent is present in the lubricating composition in an amount of 0.06 wt. % to 0.1 wt. %.

50. The composition of any one of claims 1 to 3, wherein the alkaline earth metal sulfonate comprises a mixture of 0.6 wt% to 1.5 wt% calcium sulfonate detergent having a TBN of 50 to 100 as measured according to ASTM D4739 and 0.05 wt% to 0.1 wt% overbased magnesium sulfonate detergent having a TBN of 250 to 350 as measured according to ASTM D4739.

51. The composition of any one of claims 1 to 3, wherein the total alkaline earth metal soaps of the lubricating composition are from 0.6 wt% to 1.5 wt%.

52. The composition of any one of claims 1 to 3, wherein the total alkaline earth metal soaps of the lubricating composition are from 0.7 wt% to 1.4 wt%.

53. The composition of any one of claims 1 to 3 wherein the phosphorus antiwear agent is a zinc dialkyl dithiophosphate and the zinc dialkyl dithiophosphate is present in an amount to deliver 400 ppm to 850 ppm to the lubricating composition.

54. The composition of any one of claims 1 to 3 wherein the phosphorus antiwear agent is a zinc dialkyl dithiophosphate and the zinc dialkyl dithiophosphate is present in an amount to deliver 450 ppm to 800 ppm to the lubricating composition.

55. The composition of any one of claims 1 to 3 wherein the phosphorus antiwear agent is a zinc dialkyl dithiophosphate and the zinc dialkyl dithiophosphate is present in an amount to deliver 500 ppm to 800 ppm to the lubricating composition.

56. The composition of any one of claims 1 to 3 wherein the phosphorus antiwear agent is a zinc dialkyl dithiophosphate and the zinc dialkyl dithiophosphate is present in an amount to deliver 550 ppm to 780 ppm to the lubricating composition.

57. The composition of any one of claims 1 to 3 wherein the phosphorus antiwear agent is a zinc dialkyl dithiophosphate and the zinc dialkyl dithiophosphate is present in an amount to deliver 650 ppm to 780 ppm to the lubricating composition.

58. The composition of any one of claims 1 to 3, wherein the total sulfated ash is between 0.4% and 0.8% by weight.

59. The composition of any one of claims 1 to 3, wherein the HTHS is less than 2.

5.

60. The composition of any one of claims 1 to 3, wherein the HTHS is less than 2.

3.

61. The composition of any one of claims 1 to 3, wherein the HTHS is less than 2.

1.

62. The composition of any one of claims 1 to 3, wherein the HTHS is from 1.4 to 2.

5.

63. The composition of any one of claims 1 to 3, wherein the HTHS is from 1.6 to 2.

1.

64. The composition of any one of claims 1 to 3, wherein the HTHS is from 1.8 to 2.

1.

65. The composition of any one of claims 1 to 3, wherein the HTHS is from 1.9 to 2.

0.

66. The composition of any one of claims 1 to 3 further comprising an ashless friction modifier.

67. The composition of any one of claims 1 to 3, further comprising a dispersant other than the first PIB succinimide dispersant and the second PIB succinimide dispersant.

68. The composition of any one of claims 1 to 3, further comprising one or more additional additives selected from antioxidants, foam inhibitors, and corrosion inhibitors.

69. The composition of any one of claims 1 to 3, wherein the kinematic viscosity at 100°C is from 2.5 cSt to 8.3 cSt.

70. The composition of any one of claims 1 to 3, wherein the kinematic viscosity at 100°C is from 3.5 cSt to 6.5 cSt.

71. A method of lubricating a diesel engine, the method comprising supplying the engine with a lubricant composition according to any one of the preceding claims.

72. Use of a lubricating composition according to any one of claims 1 to 69 for improving one or more of fuel economy in a diesel engine and wear protection in a diesel engine.

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