Patent Description:
Engine oil is blended with various additives to satisfy various performance requirements. One well known way to increase fuel economy is to decrease the viscosity of the lubricating oil. However, this approach is now reaching the limits of current equipment capabilities and specifications. At a given viscosity, it is well known that adding organic or organometallic friction modifiers reduces the surface friction of the lubricating oil and allows for better fuel economy. However, these additives often bring with them detrimental effects such as increased deposit formation, seals impacts, or they out-compete the anti-wear components for limited surface sites, thereby not allowing the formation of an anti-wear film, causing increased wear.

In order to improve lubricant fuel economy performance, reduction of viscosity is typically the best path (i.e., high temperature high- shear (HTHS) viscosity). HTHS is the measure of a lubricant's viscosity under severe engine conditions. Under high temperatures and high stress conditions viscosity index improver degradation can occur. As this happens, the viscosity of the oil decreases which may lead to increased engine wear.

Therefore, despite the advances in lubricant oil formulation technology, there remains a need for an engine oil lubricant that effectively improves fuel economy while providing superior anti-wear performance.

<CIT> discloses a method for reducing aqueous phase separation of an emulsion comprising ethanol-based fuel and a lubricating oil comprising molybdenum ester amide complex and a dispersant polyalkyl (meth) acrylate.

<CIT> discloses an SAE 0W-<NUM> lubricant comprises the base oil and a mixture of polymethacylate and olefin copolymer or hydrogenated diene VI improvers.

<CIT> discloses a polymethacrylate having a mass average molecular weight of <NUM>,<NUM> to <NUM>,<NUM> inclusive and (B) an olefin copolymer having a <NUM>% loss temperature of <NUM> or lower as measured by a differential thermal analysis and a shear stability index (SSI) of <NUM> or less to a lubricant oil base oil.

<CIT> discloses a mixture of at least two polymers having a difference of permanent shear stability index (PSSI).

<CIT> discloses a biodegradable lubricant that is at least <NUM>% biodegradable and has a gelation index of about <NUM> or less can be formulated using a trans-esterified triglyceride base oil together with a synthetic ester. A combination of an ester viscosity index improver and an olefin copolymer viscosity index improver also can be added.

<CIT> discloses a lubricant composition containing a (meth)-acrylate-containing polymer comprising a multiplicity of arms containing at least <NUM> carbon atoms, said arms being attached to a multivalent organic moiety; and an ethylene/olefin copolymer having a weight average molecular weight of about <NUM>,<NUM> to about <NUM>,<NUM>.

<CIT> describes lubricating oil compositions for internal combustion engines.

<CIT> describes lubricating oil compositions.

<CIT> describes low viscosity engine oil with superior engine wear protection.

<CIT> describes partly synthetic multigrade crankcase lubricant.

<CIT> describes lubricant additive compositions having improved viscosity index increasing properties.

The present invention provides a lubricating oil composition as set out in claim <NUM> and a method of improving
friction and reducing wear in an internal combustion engine as set out in claim <NUM>.

Also described herein in is a lubricating engine oil composition having a HTHS viscosity at <NUM> in a range of about <NUM> to about <NUM> cP, comprising:.

wherein the lubricating oil composition contains less than 10ppm of molybdenum containing element.

Also described herein in is a method for improving friction and reducing wear in an internal combustion engine comprising lubricating said engine with a lubricating oil composition described herein.

In this specification, the following words and expressions, if and when used, have the meanings given below.

A "major amount" means in excess of <NUM> weight % of a composition.

A "minor amount" means less than <NUM> weight % of a composition, expressed in respect of the stated additive and in respect of the total mass of all the additives present in the composition, reckoned as active ingredient of the additive or additives.

"Active ingredients" or "actives" refers to additive material that is not diluent or solvent.

All percentages reported are weight % on an active ingredient basis (i.e., without regard to carrier or diluent oil) unless otherwise stated.

The abbreviation "ppm" means parts per million by weight, based on the total weight of the lubricating oil composition.

High temperature high shear (HTHS) viscosity at <NUM> was determined in accordance with ASTM D4683.

Kinematic viscosity at <NUM> (KV<NUM>) was determined in accordance with ASTM D445.

Metal - The term "metal" refers to alkali metals, alkaline earth metals, or mixtures thereof.

Throughout the specification and claims the expression oil soluble or dispersible is used. By oil soluble or dispersible is meant that an amount needed to provide the desired level of activity or performance can be incorporated by being dissolved, dispersed or suspended in an oil of lubricating viscosity. Usually, this means that at least about <NUM>% by weight of the material can be incorporated in a lubricating oil composition. For a further discussion of the terms oil soluble and dispersible, particularly "stably dispersible", see <CIT> for relevant teachings in this regard.

The term "sulfated ash" as used herein refers to the non-combustible residue resulting from detergents and metallic additives in lubricating oil. Sulfated ash may be determined using ASTM Test D874.

The term "Total Base Number" or "TBN" as used herein refers to the amount of base equivalent to milligrams of KOH in one gram of sample. Thus, higher TBN numbers reflect more alkaline products, and therefore a greater alkalinity. TBN was determined using ASTM D <NUM> test.

Boron, calcium, magnesium, molybdenum, phosphorus, sulfur, and zinc contents were determined in accordance with ASTM D5185.

Nitrogen content was determined in accordance with ASTM D4629.

All ASTM standards referred to herein are the most current versions as of the filing date of the present application.

Olefins - The term "olefins" refers to a class of unsaturated aliphatic hydrocarbons having one or more carbon-carbon double bonds, obtained by a number of processes. Those containing one double bond are called mono-alkenes, and those with two double bonds are called dienes, alkyldienes, or diolefins. Alpha olefins are particularly reactive because the double bond is between the first and second carbons. Examples are <NUM>-octene and <NUM>-octadecene, which are used as the starting point for medium-biodegradable surfactants. Linear and branched olefins are also included in the definition of olefins.

Normal Alpha Olefins - The term "Normal Alpha Olefins" "refers to olefins which are straight chain, non-branched hydrocarbons with carbon-carbon double bond present in the alpha or primary position of the hydrocarbon chain.

Isomerized Normal Alpha Olefin. The term "Isomerized Normal Alpha Olefin" as used herein refers to an alpha olefin that has been subjected to isomerization conditions which results in an alteration of the distribution of the olefin species present and/or the introduction of branching along the alkyl chain. The isomerized olefin product may be obtained by isomerizing a linear alpha olefin containing from about <NUM> to about <NUM> carbon atoms, preferably from about <NUM> to about <NUM> carbon atoms, and preferably from about <NUM> to about <NUM> carbon atoms.

C<NUM>-<NUM> Normal Alpha Olefins - This term defines a fraction of normal alpha olefins wherein the carbon numbers below <NUM> have been removed by distillation or other fractionation methods.

Unless otherwise specified, all percentages are in weight percent.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure as defined by the appended claims.

Note that not all of the activities described in the general description or the examples are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described.

The specification and illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments.

As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or other features that are inherent to such process, method, article, or apparatus.

The use of "a" or "an" is employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the embodiments of the disclosure. This description should be read to include one or at least one and the singular also includes the plural, or vice versa, unless it is clear that it is meant otherwise. The term "averaged," when referring to a value, is intended to mean an average, a geometric mean, or a median value. Group numbers corresponding to columns within the Periodic Table of the elements use the "New Notation" convention as seen in the <NPL>).

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 to which this disclosure belongs. The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent not described herein, many details regarding specific materials and processing acts are conventional and may be found in textbooks and other sources within the lubricants as well as the oil and gas industries.

The specification and illustrations are not intended to serve as an exhaustive and comprehensive description of all the elements and features of formulations, compositions, apparatus and systems that use the structures or methods described herein. Separate embodiments may also be provided in combination in a single embodiment, and conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any sub-combination. Further, reference to values stated in ranges includes each and every value within that range. Many other embodiments may be apparent to skilled artisans only after reading this specification. Other embodiments may be used and derived from the disclosure, such that a structural substitution, logical substitution, or another change may be made without departing from the scope of the disclosure as defined by the appended claims. Accordingly, the disclosure is to be regarded as illustrative rather than restrictive.

A base oil is useful for making concentrates as well as for making lubricating oil compositions therefrom, and may be selected from natural and synthetic lubricating oils and combinations thereof.

Natural oils include animal and vegetable oils, liquid petroleum oils and hydrorefined, solvent-treated mineral lubricating oils of the paraffinic, naphthenic and mixed paraffinicnaphthenic types. Oils of lubricating viscosity derived from coal or shale are also useful base oils.

Synthetic lubricating oils include hydrocarbon oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropylenes, propylene-isobutylene copolymers, chlorinated polybutylenes, poly(<NUM>-hexenes), poly(<NUM>-octenes), poly(<NUM>-decenes); alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes, di(<NUM>-ethylhexyl)benzenes; polyphenols (e.g., biphenyls, terphenyls, alkylated polyphenols); and alkylated diphenyl ethers and alkylated diphenyl sulfides and the derivatives, analogues and homologues thereof.

Another suitable class of synthetic lubricating oils comprises the esters of dicarboxylic acids (e.g., malonic acid, alkyl malonic acids, alkenyl malonic acids, succinic acid, alkyl succinic acids and alkenyl succinic acids, maleic acid, fumaric acid, azelaic acid, suberic acid, sebacic acid, adipic acid, linoleic acid dimer, phthalic acid) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, <NUM>-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol). Specific examples of these esters include dibutyl adipate, di(<NUM>-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the <NUM>-ethylhexyl diester of linoleic acid dimer, and the complex ester formed by reacting one mole of sebacic acid with two moles of tetraethylene glycol and two moles of <NUM>-ethylhexanoic acid.

Esters useful as synthetic oils also include those made from C<NUM> to C<NUM> monocarboxylic acids and polyols, and polyol ethers such as neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol.

In one embodiment, the ester base oil is present at from about <NUM> to <NUM> wt. % based on the total weight of the lubricating oil composition. In other embodiments, the ester base oil is present at from about <NUM> to <NUM> wt. %, from about <NUM> to <NUM> wt. %, from about <NUM> to <NUM> wt. %, from about <NUM> to <NUM> wt. %, from about <NUM> to <NUM> wt. %, from about <NUM> to <NUM> wt. %, based on the total weight of the lubricating oil composition.

Unrefined, refined and re-refined oils can be used in the present lubricating oil composition. Unrefined oils are those obtained directly from a natural or synthetic source without further purification treatment. For example, a shale oil obtained directly from retorting operations, a petroleum oil obtained directly from distillation or ester oil obtained directly from an esterification process and used without further treatment would be unrefined oil. Refined oils are similar to the unrefined oils except they have been further treated in one or more purification steps to improve one or more properties. Many such purification techniques, such as distillation, solvent extraction, acid or base extraction, filtration and percolation are known to those skilled in the art. Re-refined oils are obtained by processes similar to those used to obtain refined oils applied to refined oils which have been already used in service. Such re-refined oils are also known as reclaimed or reprocessed oils and often are additionally processed by techniques for approval of spent additive and oil breakdown products.

Base oils suitable for use herein are any of the variety corresponding to API Group II, Group III, Group IV, and Group V oils and combinations thereof, preferably the Group III to Group V oils due to their exceptional volatility, stability, viscometric and cleanliness features.

The base oil constitutes the major component of the present lubricating oil composition and is present is an amount ranging from greater than <NUM> to <NUM> wt. % (e.g., <NUM> to <NUM> wt. %, or <NUM> to <NUM> wt.

The base oil may be selected from any of the synthetic or natural oils typically used as crankcase lubricating oils for spark-ignited internal combustion engines. The base oil typically has a kinematic viscosity at <NUM> in a range of <NUM> to <NUM><NUM>/s. In the case where the kinematic viscosity at <NUM> of the lubricating base oil exceeds <NUM><NUM>/s, low temperature viscosity properties may be reduced, and sufficient fuel efficiency may not be obtained. At a kinematic viscosity of <NUM><NUM>/s or less, formation of an oil film in a lubrication place is insufficient; for this reason, lubrication is inferior, and the evaporation loss of the lubricating oil composition may be increased.

Preferably, the base oil has a viscosity index of at least <NUM> (e.g., at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, or at least <NUM>). If the viscosity index is less than <NUM>, not only viscositytemperature properties, heat and oxidation stability, and anti-volatilization are reduced, but also the coefficient of friction tends to be increased; and resistance against wear tends to be reduced.

In one embodiment, the lubricating oil composition is a multi-grade oil. In another embodiment, the multi-grade oil is a viscosity grade SAE 0W-XX oil, wherein XX is any one of <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

The lubricating oil composition has a high temperature shear (HTHS) viscosity at <NUM> in the range of <NUM> to <NUM> cP (<NUM>. s to <NUM> Pa. s), <NUM> to <NUM> cP (<NUM>. s to <NUM> Pa. s) , <NUM> to <NUM> cP (<NUM>. s to <NUM> Pa. s), <NUM> to <NUM> cP (<NUM>. s to <NUM> Pa. s), or even <NUM> to <NUM> cP (<NUM>. s to <NUM> Pa.

The lubricating oil composition has a viscosity index of at least <NUM> (e.g., <NUM> to <NUM>, or <NUM> to <NUM>), at least <NUM> (e.g., <NUM> to <NUM>, <NUM> to <NUM>), at least <NUM> (e.g., <NUM> to <NUM>, or <NUM> to <NUM>), at least <NUM> (e.g., <NUM> to <NUM>, or <NUM> to <NUM>), or at least <NUM> (e.g., <NUM> to <NUM>, or <NUM> to <NUM>). If the viscosity index of the lubricating oil composition is less than <NUM>, it may be difficult to improve fuel efficiency while maintaining the HTHS viscosity at <NUM>. If the viscosity index of the lubricating oil composition exceeds <NUM>, evaporation properties may be reduced, and deficits due to insufficient solubility of the additive and matching properties with a seal material may be caused.

The lubricating oil composition has a kinematic viscosity at <NUM> in a range of <NUM> to <NUM><NUM>/s (e.g., <NUM> to <NUM><NUM>/s, <NUM> to <NUM><NUM>/s, or <NUM> to <NUM><NUM>/s).

In general, the level of sulfur in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of sulfur of about <NUM> wt. % to about <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> wt. % to <NUM> wt. In one embodiment, the level of sulfur in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, less than or equal to about <NUM> wt. %, less than or equal to about <NUM> wt. %, less than or equal to about <NUM> wt. %, less than or equal to about <NUM> wt. %, less than or equal to about <NUM> wt. % based on the total weight of the lubricating oil composition.

In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt. In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt. In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt. In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt. In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt. In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt. In one embodiment, the levels of phosphorus in the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. %, based on the total weight of the lubricating oil composition, e.g., a level of phosphorus of about <NUM> wt. % to about <NUM> wt.

In one embodiment, the level of sulfated ash produced by the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. % as determined by ASTM D <NUM>, e.g., a level of sulfated ash of from about <NUM> to about <NUM> wt. % as determined by ASTM D <NUM>. In one embodiment, the level of sulfated ash produced by the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. % as determined by ASTM D <NUM>, e.g., a level of sulfated ash of from about <NUM> to about <NUM> wt. % as determined by ASTM D <NUM>. In one embodiment, the level of sulfated ash produced by the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. % as determined by ASTM D <NUM>, e.g., a level of sulfated ash of from about <NUM> to about <NUM> wt. % as determined by ASTM D <NUM>. In one embodiment, the level of sulfated ash produced by the lubricating oil compositions of the present invention is less than or equal to about <NUM> wt. % as determined by ASTM D <NUM>, e.g., a level of sulfated ash of from about <NUM> to about <NUM> wt. % as determined by ASTM D <NUM>.

Suitably, the present lubricating oil composition may have a total base number (TBN) of <NUM> to <NUM> KOH/g (e.g., <NUM> to <NUM> KOH/g, <NUM> to <NUM> KOH/g, or <NUM> to <NUM> KOH/g).

Viscosity modifiers (VM) or viscosity index improvers (VIIs) are used in the lubricant to impart high and low temperature operability. VM may be used to impart that sole function or may be multifunctional. Multifunctional viscosity modifiers also provide additional functionality for dispersant function. Examples of Viscosity modifiers and dispersant viscosity modifiers are polymethacrylates, polyacrylates, polyolefms, styrene-maleic ester copolymer and similar polymeric substances including homopolymers, copolymers and graft copolymers.

In one embodiment, the VIIs can be present in the lubricating oil composition from <NUM> to <NUM> wt. % based on the lubricating oil composition. In other embodiments, the VIIs can be present from <NUM> to <NUM> wt. %, from <NUM> to <NUM> wt. %, from <NUM> to <NUM> wt. %, from <NUM> to <NUM> wt. %, from <NUM> to <NUM> wt. %, from <NUM> to <NUM> wt. % the lubricating oil composition.

Particularly useful in this disclosure is the combination of a dispersant polymethacrylate VII and an ethylene based non-dispersant VII.

Dispersant PMAs may have a weight average molecular weight of from <NUM>,<NUM>/mol to <NUM>,<NUM>/mol, from <NUM>,<NUM>/mol to <NUM>,<NUM>/mol, from <NUM>,<NUM>/mol to <NUM>,<NUM>/mol, or from <NUM>,<NUM>/mol to <NUM>,<NUM>/mol.

Dispersant polymethacrylate (DPMA) viscosity index modifiers can be described as follows, and are described in <CIT>. Dispersant polymethacrylate (DPMA) viscosity index modifiers include Viscoplex® viscosity index improvers <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM>, all available from Evonik RohMax Additives GmbH of Darmstadt, Germany. Polyalkyl(meth)acrylate(s) may comprise monomer units of:.

The DPMA used in the present invention is believed to contain about <NUM> to <NUM> wt. % methyl methacrylate monomer, about <NUM> to <NUM> wt. % N-vinyl pyrrolidone as the nitrogen-containing monomer, and the balance longer chain alkyl methacrylate monomers, in particular, lauryl methacrylate, and has a MW of from <NUM>,<NUM> to <NUM>,<NUM>. It has an SSI of from about <NUM> to about <NUM>.

Non-dispersant ethylene-based olefin copolymer VIIs have a weight average molecular weight of <NUM>,<NUM>/mol to110,<NUM>/mol.

The ethylene-based viscosity index modifier used in the present invention can be described as follows, and as set forth in <CIT>.

The ethylene-based VII is an ethylene propylene copolymer.

In one embodiment, the polymer compositions typically contain about <NUM> wt % to about <NUM> wt % of the first ethylene-α-olefin copolymer (a) and about <NUM> wt % to about <NUM> wt % of the second ethylene-α-olefin copolymer (b) based upon the total amount of (a) and (b) in the composition. In another embodiment, the polymer compositions typically contain about <NUM> wt % to about <NUM> wt % of the first ethylene-α-olefin copolymer (a) and about <NUM> wt % to about <NUM> wt % of the second ethylene-α-olefin copolymer (b) based upon the total amount of (a) and (b) in the composition. In a particular embodiment, the polymer composition contains about <NUM> to about <NUM> wt % of the first ethylene-α-olefin copolymer (a) and about <NUM> to about <NUM> wt % of the second ethylene-α-olefin copolymer (b) based upon the total amount of (a) and (b) in the composition.

The first ethylene-α-olefin copolymer described herein may have a weight average molecular weight of about <NUM>,<NUM>/mol to about <NUM>,<NUM>/mol. The first ethylene-α-olefin copolymer described herein may have a weight average molecular weight of <NUM>,<NUM>/mol to about <NUM>,<NUM>/mol. The second ethylene-α-olefin copolymer described herein may have a weight average molecular weight of <NUM>,<NUM>/mol to about <NUM>,<NUM>/mol. The second ethylene-α-olefin copolymer described herein may have a weight average molecular weight of <NUM>,<NUM>/mol to about <NUM>,<NUM>/mol. The weight average molecular weight of the composition of the first ethylene-α-olefin copolymer and second ethylene-α-olefin copolymer in one embodiment is typically about <NUM>,<NUM>/mol to about <NUM>,<NUM>/mol. In a still further embodiment, the weight average molecular weight of the composition of the first ethylene-α-olefin copolymer and second ethylene-α-olefin copolymer is typically about <NUM>,<NUM> to about <NUM>,<NUM>/mol. The molecular weight distribution of each of the ethylene-α-olefin copolymers is typically less than about <NUM>, and more typically about <NUM> to about <NUM>. The polymer distribution as determined by GPC is typically unimodal.

The polymer compositions have a total ethylene content of <NUM> wt. % to <NUM> wt. In other embodiments, the polymer composition has a total ethylene content of about <NUM> wt. % to about <NUM> wt.

Salicylates may be prepared by reacting a basic metal compound with at least one carboxylic acid and removing water from the reaction product. Detergents made from salicylic acid are one class of detergents prepared from carboxylic acids. Useful salicylates include long chain alkyl salicylates. One useful family of compositions is of the following structure (<NUM>):
<CHM>
wherein R" is a C<NUM> to C<NUM> (e.g., C<NUM> to C<NUM>) alkyl group; n is an integer from <NUM> to <NUM>; and M is an alkaline earth metal (e.g., Ca or Mg).

Hydrocarbyl-substituted salicylic acids may be prepared from phenols by the Kolbe reaction (see <CIT>). The metal salts of the hydrocarbyl-substituted salicylic acids may be prepared by double decomposition of a metal salt in a polar solvent such as water or alcohol.

In one aspect of the present disclosure, the salicylate is derived from C<NUM>-C<NUM> isomerized NAO and is made from an alkylphenol with an alkyl group derived from an isomerized NAO having an isomerization level (i) from about <NUM> to about <NUM>, preferably from about <NUM> to about <NUM>, preferably from about <NUM> to about <NUM>, and more preferably from about <NUM> to about <NUM>.

A typical detergent is an anionic material that contains a long chain hydrophobic portion of the molecule and a smaller anionic or oleophobic hydrophilic portion of the molecule. The anionic portion of the detergent is typically derived from an organic acid such as a sulfur acid, carboxylic acid, phosphorous acid, phenol, or mixtures thereof. The counterion is typically an alkaline earth or alkali metal.

Salts that contain a substantially stoichiometric amount of the metal are described as neutral salts and have a total base number (TBN) of from <NUM> to <NUM> KOH/g. Many compositions are overbased, containing large amounts of a metal base that is achieved by reacting an excess of a metal compound (e.g., a metal hydroxide or oxide) rich an acidic gas (e.g., carbon dioxide). Useful detergents can be neutral, mildly overbased, or highly overbased.

It is desirable for at least some detergent used in the detergent mixture to be overbased. Overbased detergents help neutralize acidic impurities produced by the combustion process and become entrapped in the oil. Typically, the overbased material has a ratio of metallic ion to anionic portion of the detergent of <NUM>:<NUM> to <NUM>:<NUM> (e.g., <NUM>:<NUM> to <NUM>:<NUM>) on an equivalent basis. The resulting detergent is an overbased detergent that will typically have a TBN of <NUM> KOH/g or higher (e.g., <NUM> to <NUM> KOH/g or more). A mixture of detergents of differing TBN can be used.

Suitable detergents include metal salts of sulfonates, phenates, carboxylates, phosphates, and salicylates.

Sulfonates may be prepared from sulfonic acids which are typically obtained by the sulfonation of alkyl-substituted aromatic hydrocarbons such as those obtained from the fractionation of petroleum or by the alkylation of aromatic hydrocarbons. Examples included those obtained by alkylating benzene, toluene, xylene, naphthalene, diphenyl or their halogen derivatives. The alkylation may be carried out in the presence of a catalyst with alkylating agents having from about <NUM> to more than <NUM> carbon atoms. The alkaryl sulfonates usually contain from about <NUM> to <NUM> or more carbon atoms (e.g., about <NUM> to <NUM> carbon atoms) per alkyl substituted aromatic moiety.

Phenates can be prepared by reacting an alkaline earth metal hydroxide or oxide (e.g., CaO, Ca(OH)<NUM>, MgO, or Mg(OH)<NUM>) with an alkyl phenol or sulfurized alkylphenol. Useful alkyl groups include straight or branched chain C<NUM> to C<NUM> (e.g., C<NUM> to C<NUM>) alkyl groups, or mixtures thereof. Examples of suitable phenols include isobutylphenol, <NUM>-ethylhexylphenol, nonylphenol, dodecyl phenol, and the like. It should be noted that starting alkylphenols may contain more than one alkyl substituent that are each independently straight chain or branched chain. When a non-sulfurized alkylphenol is used, the sulfurized product may be obtained by methods well known in the art. These methods include heating a mixture of alkylphenol and sulfurizing agent (e.g., elemental sulfur, sulfur halides such as sulfur dichloride, and the like) and then reacting the sulfurized phenol with an alkaline earth metal base.

Preferred magnesium-containing detergents include magnesium sulfonates, magnesium phenates, and magnesium salicylates, especially magnesium sulfonates and salicylates. These can be as described above.

The magnesium-containing detergent is used in an amount that provides at least <NUM> ppm to <NUM> ppm (for example, <NUM> ppm to <NUM> ppm, <NUM> to <NUM> ppm, <NUM> to <NUM> ppm, <NUM> to <NUM> ppm, <NUM> to <NUM> ppm, <NUM> to <NUM> ppm, <NUM> to <NUM> ppm, <NUM> to <NUM> ppm, or <NUM> to <NUM> ppm) by weight of magnesium to the lubricating oil composition.

The levels of molybdenum containing element in the lubricating oil compositions of the present invention is less than <NUM> ppm, based on the total weight of the lubricating oil composition, e.g., a level of molybdenum containing element of about <NUM> to less than <NUM> ppm. In one embodiment, the levels of molybdenum containing element in the lubricating oil compositions of the present invention is less than or equal to about <NUM> ppm, based on the total weight of the lubricating oil composition, e.g., a level of molybdenum containing element of about <NUM> to about <NUM> ppm.

In other embodiments, the lubricating oil composition is substantially free of molybdenum containing element. In some embodiments, substantially free of molybdenum containing element means the molybdenum containing element is present at less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM> ppm.

In addition to the additives compound described herein, the lubricating oil composition can comprise additional lubricating oil additives.

The lubricating oil compositions of the present disclosure may also contain other conventional additives that can impart or improve any desirable property of the lubricating oil composition in which these additives are dispersed or dissolved. Any additive known to a person of ordinary skill in the art may be used in the lubricating oil compositions disclosed herein. Some suitable additives have been described in <NPL>); and <NPL>). For example, the lubricating oil compositions can be blended with antioxidants, anti-wear agents, metal detergents, rust inhibitors, dehazing agents, demulsifying agents, metal deactivating agents, friction modifiers, pour point depressants, antifoaming agents, co-solvents, corrosioninhibitors, ashless dispersants, multifunctional agents, dyes, extreme pressure agents and the like and mixtures thereof. A variety of the additives are known and commercially available. These additives, or their analogous compounds, can be employed for the preparation of the lubricating oil compositions of the disclosure by the usual blending procedures.

The lubricating oil composition of the present invention can contain one or more anti-wear agents that can reduce friction and excessive wear. Any anti-wear agent known by a person of ordinary skill in the art may be used in the lubricating oil composition. Non-limiting examples of suitable anti-wear agents include zinc dithiophosphate, metal (e.g., Pb, Sb, Mo and the like) salts of dithiophosphates, metal (e.g., Zn, Pb, Sb, Mo and the like) salts of dithiocarbamates, metal (e.g., Zn, Pb, Sb and the like) salts of fatty acids, boron compounds, phosphate esters, phosphite esters, amine salts of phosphoric acid esters or thiophosphoric acid esters, reaction products of dicyclopentadiene and thiophosphoric acids and combinations thereof. The amount of the anti-wear agent may vary from about <NUM> wt. % to about <NUM> wt. %, from about <NUM> wt. % to about <NUM> wt. %, or from about <NUM> wt. % to about <NUM> wt. %, based on the total weight of the lubricating oil composition.

In certain embodiments, the anti-wear agent is or comprises a dihydrocarbyl dithiophosphate metal salt, such as zinc dialkyl dithiophosphate compounds. The metal of the dihydrocarbyl dithiophosphate metal salt may be an alkali or alkaline earth metal, or aluminum, lead, tin, molybdenum, manganese, nickel or copper. In some embodiments, the metal is zinc. In other embodiments, the alkyl group of the dihydrocarbyl dithiophosphate metal salt has from about <NUM> to about <NUM> carbon atoms, from about <NUM> to about <NUM> carbon atoms, from about <NUM> to about <NUM> carbon atoms, or from about <NUM> to about <NUM> carbon atoms. In further embodiments, the alkyl group is linear or branched.

The amount of the dihydrocarbyl dithiophosphate metal salt including the zinc dialkyl dithiophosphate salts in the lubricating oil composition disclosed herein is measured by its phosphorus content. In some embodiments, the phosphorus content of the lubricating oil composition disclosed herein is from about <NUM> wt. % to about <NUM> wt. %, based on the total weight of the lubricating oil composition.

The lubricating oil composition of the present invention can contain one or more friction modifiers that can lower the friction between moving parts. Any friction modifier known by a person of ordinary skill in the art may be used in the lubricating oil composition. Non-limiting examples of suitable friction modifiers include fatty carboxylic acids; derivatives (e.g., alcohol, esters, borated esters, amides, metal salts and the like) of fatty carboxylic acid; mono-, di- or tri-alkyl substituted phosphoric acids or phosphonic acids; derivatives (e.g., esters, amides, metal salts and the like) of mono-, di- or tri-alkyl substituted phosphoric acids or phosphonic acids; mono-, di- or tri-alkyl substituted amines; mono- or di-alkyl substituted amides and combinations thereof. In some embodiments examples of friction modifiers include, but are not limited to, alkoxylated fatty amines; borated fatty epoxides; fatty phosphites, fatty epoxides, fatty amines, borated alkoxylated fatty amines, metal salts of fatty acids, fatty acid amides, glycerol esters, borated glycerol esters; and fatty imidazolines as disclosed in <CIT>; friction modifiers obtained from a reaction product of a C<NUM> to C<NUM>, or a C<NUM> to C<NUM>, or a C<NUM> to C<NUM>, fatty acid ester and a nitrogen-containing compound selected from the group consisting of ammonia, and an alkanolamine and the like and mixtures thereof. The amount of the friction modifier may vary from about <NUM> wt. % to about <NUM> wt. %, from about <NUM> wt. % to about <NUM> wt. %, or from about <NUM> wt. % to about <NUM> wt. %, based on the total weight of the lubricating oil composition.

The lubricating oil composition of the invention preferably contains an organic oxidation inhibitor in an amount of <NUM>-<NUM> wt. %, preferably <NUM>-<NUM> wt. The oxidation inhibitor can be a hindered phenol oxidation inhibitor or a diarylamine oxidation inhibitor. The diarylamine oxidation inhibitor is advantageous in giving a base number originating from the nitrogen atoms. The hindered phenol oxidation inhibitor is advantageous in producing no NOx gas.

Examples of the hindered phenol oxidation inhibitors include <NUM>,<NUM>-di-t-butyl-p-cresol, <NUM>,<NUM>' -methylenebis(<NUM>,<NUM>-di-t-butylphenol), <NUM>,<NUM>' -methylenebis(<NUM>-t-butyl-o-cresol), <NUM>,<NUM>' - isopropylidenebis(<NUM>,<NUM>-di-t-butylphenol), <NUM>,<NUM>' -bis(<NUM>,<NUM>-di-t-butylphenol), <NUM>,<NUM>' -methylenebis(<NUM>-methyl-<NUM>-t-butylphenol), <NUM>,<NUM>' -thiobis(<NUM>-methyl-<NUM>-t-butylphenol), <NUM>,<NUM>-thio-diethylenebis[<NUM>-(<NUM>,<NUM>-di-t-butyl-<NUM>-hydroxyphenyl)propionate], octyl <NUM>-(<NUM>,<NUM>-di-t-butyl-<NUM>-hydroxyphenyl)propionate, octadecyl <NUM>-(<NUM>,<NUM>-di-t-butyl-<NUM>-hydroxyphenyl)propionate, and octyl <NUM>-(<NUM>,<NUM>-butyl-<NUM>-hydroxy-<NUM>-methylphenyl)propionate, and commercial products such as, but not limited to, Irganox L135® (BASF), Naugalube <NUM>® (Chemtura), and Ethanox <NUM>® (SI Group). Examples of the diarylamine oxidation inhibitors include alkyldiphenylamine having a mixture of alkyl groups of <NUM> to <NUM> carbon atoms, p,p' -dioctyldiphenylamine, phenyl-naphthylamine, phenyl-naphthylamine, alkylated-naphthylamine, and alkylated phenyl-naphthylamine.

Each of the hindered phenol oxidation inhibitor and diarylamine oxidation inhibitor can be employed alone or in combination.

The lubricating oil compositions disclosed herein can be prepared by any method known to a person of ordinary skill in the art for making lubricating oils. In some embodiments, the base oil can be blended or mixed with the zirconium-containing compounds described herein. Optionally, one or more other can be added. The additives may be added to the base oil individually or simultaneously. In some embodiments, the additives are added to the base oil individually in one or more additions and the additions may be in any order. In other embodiments, the additives are added to the base oil simultaneously, optionally in the form of an additive concentrate. In some embodiments, the solubilizing of the additives in the base oil may be assisted by heating the mixture to a temperature from about <NUM> to about <NUM>, from about <NUM> to about <NUM> or from about <NUM> to about <NUM>.

Any mixing or dispersing equipment known to a person of ordinary skill in the art may be used for blending, mixing or solubilizing the ingredients. The blending, mixing or solubilizing may be carried out with a blender, an agitator, a disperser, a mixer (e.g., planetary mixers and double planetary mixers), a homogenizer (e.g., Gaulin homogenizers and Rannie homogenizers), a mill (e.g., colloid mill, ball mill and sand mill) or any other mixing or dispersing equipment known in the art.

The lubricating oil composition disclosed herein may be suitable for use as motor oils (that is, engine oils or crankcase oils), in a spark-ignited internal combustion engine, particularly direct injected and boosted engines.

The following examples are presented to exemplify embodiments of the invention but are not intended to limit the invention to the specific embodiments set forth. Unless indicated to the contrary, all parts and percentages are by weight. All numerical values are approximate. When numerical ranges are given, it should be understood that embodiments outside the stated ranges may still fall within the scope of the invention. Specific details described in each example should not be construed as necessary features of the invention.

The following examples are intended for illustrative purposes only and do not limit in any way the scope of the present invention.

A lubricating oil composition was prepared by blending together the following components to obtain an SAE 0W-<NUM> viscosity grade formulation free of molybdenum:.

Example <NUM> was replicated except the calcium salicylate was derived from a C<NUM>-C<NUM> isomerized normal alpha olefin with an isomerization level of the alpha olefin is about <NUM>. The additive contained <NUM> wt. % Ca, and about <NUM> wt. % diluent oil, and had a TBN of about <NUM> KOH/g and a basicity index of about <NUM>. On an actives basis, the TBN of this additive is about <NUM> KOH/g.

The isomerization level was measured by an NMR method.

The isomerization level (I) of the olefin was determined by hydrogen-<NUM> (<NUM>) NMR. The NMR spectra were obtained on a Bruker Ultrashield Plus <NUM> in chloroform-d1 at <NUM> using TopSpin <NUM> spectral processing software.

The isomerization level (I) represents the relative amount of methyl groups (-CH<NUM>) (chemical shift <NUM>-<NUM> ppm) attached to the methylene backbone groups (-CH<NUM>-) (chemical shift <NUM>-<NUM> ppm) and is defined by Formula (<NUM>) as shown below,<MAT> where m is NMR integral for methyl groups with chemical shifts between <NUM> ± <NUM> to <NUM> ± <NUM> ppm, and n is NMR integral for methylene groups with chemical shifts between <NUM> ± <NUM> to <NUM> ± <NUM> ppm.

Example <NUM> was replicated except the magnesium sulfonate detergent was present in an amount to provide <NUM> ppm of magnesium.

Example <NUM> was replicated except the C<NUM>-C<NUM> normal alpha olefin derived overbased calcium salicylate was removed.

Example <NUM> was replicated except that <NUM> wt. % of an ester base oil was added to the finished oil.

Example <NUM> was replicated except the calcium salicylate was substituted with a magnesium salicylate which was derived from a C<NUM>-C<NUM> isomerized normal alpha olefin with an isomerization level of the alpha olefin is about <NUM>. The additive contained <NUM> wt. % Mg, and about <NUM> wt. % diluent oil, and had a TBN of about <NUM> KOH/g. Isomerization level was measured as in Example <NUM>.

Example <NUM> was replicated except the calcium salicylate was substituted with a magnesium salicylate which was derived from a C<NUM>-C<NUM> alpha olefin and had a TBN of about <NUM> mgKOH/g and <NUM> wt.

Example <NUM> was replicated except that the ethylene propylene derived non-dispersant OCP was replaced with <NUM> wt. % of polymer concentrate which contains a hydrogenated polyisoprene star polymer coupled with divinylbenzene with an SSI of <NUM> and a molecular weight of <NUM>,<NUM>.

Example <NUM> was replicated except that <NUM> wt. % of a sulfur free molybdenum compound was added in an amount to provide <NUM> ppm of molybdenum to the lubricating oil composition.

Example <NUM> was replicated except that <NUM> wt. % of a sulfur free molybdenum compound and <NUM> wt. % of a sulfur containing molybdenum succinimide complex was added in an amount to provide <NUM> ppm of molybdenum to the lubricating oil.

Example <NUM> was replicated except that <NUM> wt. % of a sulfur free molybdenum compound was added in an amount to provide <NUM> ppm of molybdenum to the lubricating oil.

Example <NUM> was replicated except the ethylene propylene derived non-dispersant OCP and dispersant PMA was replaced with <NUM> wt. % of polymer concentrate which contains a hydrogenated polyisoprene star polymer coupled with divinylbenzene with an SSI of <NUM> and a molecular weight of <NUM>,<NUM> and <NUM> wt. % of a sulfur containing molybdenum succinimide complex was added in an amount to provide <NUM> ppm of molybdenum to the lubricating oil composition.

Comparative Example <NUM> was replicated except the ethylene propylene derived non-dispersant OCP and dispersant PMA was replaced with <NUM> wt. % of polymer concentrate which contains a hydrogenated polyisoprene star polymer coupled with divinylbenzene with an SSI of <NUM> and a molecular weight of <NUM>,<NUM>.

Example <NUM> was replicated except that the ethylene propylene derived non-dispersant OCP was replaced with a <NUM> wt. % of a polymer concentrate of a dispersant OCP.

Performance evaluation of the formulations is given in Table <NUM>. The following bench test was performed to measure wear: FZG Wear Scuffing Load Carrying Capacity Test. In order to evaluate wear performance of the automotive engine oils, the load carrying characteristics of various engine oils having different chemistries were evaluated on an FZG test rig (FZG four-square test machine) using A10 gears according to CEC-L-<NUM>-A-<NUM>. This method is useful for evaluating the scuffing load capacity potential of oils typically used with highly stressed cylindrical gearing found in many vehicle and stationary applications. Theminimum load stage fail was <NUM> for the A10 gears at <NUM>/s and <NUM>.

Claim 1:
A lubricating oil composition having a HTHS viscosity at <NUM> in a range of <NUM> to <NUM> cP (<NUM>.0013Pa.s to <NUM> Pa.s), comprising:
a) a major amount of an oil of lubricating viscosity having a kinematic viscosity at <NUM> in a range of <NUM> to <NUM><NUM>/s;
b) a dispersant polymethacrylate (DPMA) VII having a Mw of from <NUM>,<NUM>/mol to <NUM>,<NUM>/mol and a SSI of from <NUM> to <NUM>,
the dispersant polymethacrylate (DPMA) VII containing: <NUM> to <NUM> wt.% methyl methacrylate monomer; <NUM> to <NUM> wt.% N-vinyl pyrrolidone as the nitrogen-containing monomer; and the balance longer chain alkyl methacrylate monomers, in particular, lauryl methacrylate;
c) a non-dispersant ethylene-based olefin copolymer viscosity index improver having a Mw of from <NUM>,<NUM>/mol to <NUM>,<NUM>/mol and a total ethylene content of <NUM> wt % to <NUM> wt %, wherein the non-di spersant ethylene-based olefin copolymer is an ethylene propylene copolymer;
d) from <NUM> to <NUM> ppm of magnesium from a magnesium containing detergent; and
wherein the lubricating oil composition contains less than <NUM> ppm of a molybdenum containing element,
wherein the HTHS viscosity at <NUM> was determined in accordance with ASTM D4683.