Patent Description:
Traditionally, high-performance lubricating calcium sulfonate greases are prepared by converting the over-based calcium sulfonate's amorphous particle to a crystalline state, also known as gelation. During the gelation process, calcium carbonate, along with one or more promotors such as water, acids, alcohols, amines, etc. that destabilize the sulfonate's micellular structure, are used to convert the amorphous particle to crystalline particles of calcite or vaterite. The promotors used during the gelation process are also referred to as converting agents. Typical converting agents are used in the range of <NUM> to <NUM> weight percent ("wt%"), based on the total yield of the grease.

Greases often have additives, called extreme pressure additives or agents, to prevent or reduce sliding metal surfaces from seizing under severe contact conditions. Traditionally, extreme pressure additives, such as molybdenum disulfide or phosphoric acid have been added to improve the extreme pressure properties of the grease. These extreme pressure additives can be expensive and, in some cases, environmentally unfriendly. These extreme pressure additives may also be detrimental to other desired properties of the grease. For example, phosphoric acid may interfere with anti-corrosion properties of the grease. <CIT> and <CIT> disclose grease compositions comprising overbased detergents.

It was surprisingly found that overbased metal detergent greases made using a polyalkylene glycol wherein the polyalkylene glycol is a methoxypolyethyleneglycol having a number average (Mn) molecular weight of <NUM> to <NUM> Mn, <NUM> to <NUM> Mn, or <NUM> to <NUM> Mn, wherein the grease is made in a two-step process having a gelation step and a complexing step, wherein the polyalkylene glycol is added as a promotor during the gelation step.

The polyalkylene glycol may be present in a range of <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>, or <NUM> to <NUM> or <NUM> to <NUM> weight percent based on a total yield of the grease.

In other embodiments, an acid having at least one of both a nitrogen and a sulfur atom, is present in a range of <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM> or <NUM> to <NUM> weight percent based on a total yield of the grease. In one embodiment, the acid may be a sulfonic acid having at least one amine and/or amide functional group. In another embodiment, the sulfonic acid may comprise at least one of sulfamic acid, <NUM>-acrylamido <NUM>-methyl propane sulfonic acid, or combinations thereof.

In another embodiment, the grease may comprise the adduct of an acid and a polyalkylene glycol. The weight ratio of the acid to polyalkylene glycol may range from <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, or <NUM>:<NUM> to <NUM>:<NUM>. In yet another embodiment, the adduct may be the adduct of sulfamic acid and methoxypolyethylene glycol.

In yet other embodiments, the overbased metal detergent may be an overbased metal sulfonate, salicylate, naphthalene, naphthenate, phenate or oleate detergent, or mixtures thereof. The overbased metal detergent may be present in a range of <NUM> to <NUM>, or <NUM> to <NUM> weight percent based on a total yield of the grease. In yet other embodiments, the grease is a food-grade grease.

In some embodiments, the grease comprises at least one base oil selected from highly refined mineral oils ("liquid paraffin" or "white oil"), polyalphaolefin, polyalkylene glycol, seed oil, vegetable oil ("esters"), or mixtures thereof. In other embodiments, the grease may comprise an oil of lubricating viscosity selected from at least one API Group I, II, III, IV, or V oil, naphthenic oil, silicone oil, esters, or mixtures thereof.

The grease as described in any of the embodiments above, may have an extreme pressure performance, as measured by the Standard Test Method for Measurement of Extreme-Pressure Properties of Lubricating Grease ("Four-Ball Method") ASTM D2596, of passing, or at least <NUM>-f. In yet another embodiment, the weld point using the Four-Ball Method of the grease may be at least <NUM>-f. In some embodiments, the grease may have a copper corrosion value as measured using ASTM D4048 of 1B or better. In other embodiments, the grease may have a wear test result of less than or equal to <NUM> using ASTM D2266.

The disclosed grease may be made using a variety of methods. One method may comprise a gelation step and a complexing step, and wherein an acid having at least one of both a nitrogen and a sulfur atom is used in said complexing step.

Methods of lubricating a mechanical component using the grease described above are also disclosed. The method may comprise contacting a mechanical component with a grease. Mechanical components can include gears, drivetrain elements, bearings, hinges, or combinations thereof.

Method of improving the extreme pressure performance of an overbased metal sulfonate grease are also disclosed. The extreme pressure performance can be measured by the Standard Test Method for Measurement of Extreme-Pressure Properties of Lubricating Grease (Four-Ball Method), ASTM D2596.

Except in the Examples, or where otherwise explicitly indicated, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by the word "about. " It is to be understood that the upper and lower amount, range, and ratio limits set forth herein may be independently combined. Similarly, the ranges and amounts for each element of the invention can be used together with ranges or amounts for any of the other elements.

As used herein, the transitional term "comprising," which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, un-recited elements or method steps. However, in each recitation of "comprising" herein, it is intended that the term also encompass, as alternative embodiments, the phrases "consisting essentially of" and "consisting of," where "consisting of" excludes any element or step not specified and "consisting essentially of" permits the inclusion of additional un-recited elements or steps that do not materially affect the basic and novel characteristics of the composition or method under consideration.

Various features and embodiments will be described below by way of nonlimiting descriptions and examples. In one embodiment, an overbased metal detergent grease comprising at least one of polyalkylene glycol and/or an acid having at least one of both a nitrogen and a sulfur atom is disclosed.

The polyalkylene glycol may have a number average (Mn) molecular weight of <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM>. In other embodiments, the polyalkylene glycol is present in a range of <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>, or <NUM> to <NUM> or <NUM> to <NUM> weight percent based on a total yield of the grease. The polyalkylene glycol is a methoxypolyethylene glycol. Commercially available polyalkylene glycols include MPEG <NUM> Sentry Grade.

The acid may be present in a range of <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM> or <NUM> to <NUM> weight percent based on a total yield of the grease. In some embodiments, the acid may be sulfamic acid.

In some embodiments, the grease may comprise the adduct of an acid and a polyalkylene glycol. The weight ratio of the acid to polyalkylene glycol may range from <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, or <NUM>:<NUM> to <NUM>:<NUM>. In yet other embodiments, the grease comprises an adduct of sulfamic acid and methoxypolyethylene glycol.

The acid used to make the grease has at least one of both a nitrogen and a sulfur atom. Suitable acids are not overly limited and may be a sulfonic acid having at least one amine and/or amide functional group. In another embodiment, the sulfonic acid may comprise at least one of sulfamic acid, <NUM>-acrylamido <NUM>-methyl propane sulfonic acid, or combinations thereof.

The <NUM>-acrylamido <NUM>-methyl propane sulfonic acid may have the structure below.

The grease may be prepared using any overbased metal detergent known in the art. Overbased metal detergents, otherwise referred to as overbased detergents, metal-containing overbased detergents or superbased salts, are characterized by a metal content in excess of that which would be necessary for neutralization according to the stoichiometry of the metal and the particular acidic organic compound, i.e. the substrate, reacted with the metal. The overbased detergent may comprise one or more of non-sulfur containing phenates, sulfur containing phenates, sulfonates, salicylates, and mixtures thereof. Alternatively, the overbased metal detergent may comprise at least one overbased metal sulfonate, salicylate, naphthalene, naphthenate, or oleate detergent, or mixtures thereof.

The amount of excess metal is commonly expressed in terms of substrate to metal ratio. The terminology "metal ratio" is used in the prior art and herein to define the ratio of the total chemical equivalents of the metal in the overbased salt to the chemical equivalents of the metal in the salt which would be expected to result from the reaction between the hydrocarbyl substituted organic acid; the hydrocarbyl-substituted phenol or mixtures thereof to be overbased, and the basic metal compound according to the known chemical reactivity and the stoichiometry of the two reactants. Thus, in a normal or neutral salt (i.e. soap) the metal ratio is one and, in an overbased salt, the metal ratio is greater than one, especially greater than <NUM>. The overbased detergent may have a metal ratio of <NUM> to <NUM>, or a metal ratio of <NUM> to <NUM>, or a metal ratio of at least <NUM>.

The metal-containing detergent may also include "hybrid" detergents formed with mixed surfactant systems including phenate and/or sulfonate components, e.g. phenate-salicylates, sulfonate-phenates, sulfonate-salicylates, and sulfonates-phenates-salicylates. Where, for example, a hybrid sulfonate/phenate detergent is employed, the hybrid detergent would be considered equivalent to amounts of distinct phenate and sulfonate detergents introducing like amounts of phenate and sulfonate soaps, respectively. Overbased phenates and salicylates typically have a total base number of <NUM> to <NUM> TBN. Overbased sulfonates typically have a total base number of <NUM> to <NUM>, or <NUM> to <NUM>.

Alkylphenols are often used as constituents in and/or building blocks for overbased detergents. Alkylphenols may be used to prepare phenate, salicylate, salixarate, or saligenin detergents or mixtures thereof. Suitable alkylphenols may include para-substitued hydrocarbyl phenols. The hydrocarbyl group may be linear or branched aliphatic groups of <NUM> to <NUM> carbon atoms, <NUM> to <NUM> carbon atoms, <NUM> to <NUM> carbon atoms, <NUM> to <NUM> carbon atoms, or <NUM> to <NUM> carbon atoms.

The overbased metal-containing detergent may be alkali metal or alkaline earth metal salts. In one embodiment, the overbased detergent may be sodium salts, calcium salts, magnesium salts, barium salts, lithium salts or mixtures thereof of the phenates, sulfur-containing phenates, sulfonates, salixarates, salicylates, naphthalenes, naphthenates, or oleates, or mixtures thereof. In one embodiment, the overbased detergent is a calcium detergent, a magnesium detergent or mixtures thereof. In one embodiment, both calcium and magnesium containing detergents may be present in the grease. Calcium and magnesium detergents may be present such that the weight ratio of calcium to magnesium is <NUM>:<NUM> to <NUM>:<NUM>, or <NUM>:<NUM> to <NUM>:<NUM>, or <NUM>:<NUM> to <NUM>:<NUM>. In one embodiment, the overbased detergent is free of or substantially free of sodium.

In one embodiment, the sulfonate detergent may be predominantly a linear alkylbenzene sulfonate detergent having a metal ratio of at least <NUM>. The linear alkyl group may be attached to the benzene ring anywhere along the linear chain of the alkyl group, but often in the <NUM>, <NUM> or <NUM> position of the linear chain, and in some instances, predominantly in the <NUM> position, resulting in the linear alkylbenzene sulfonate detergent.

Salicylate detergents and overbased salicylate detergents may be prepared in at least two different manners. In a first manner, the detergent may be prepared via carbonylation (also referred to as carboxylation) of a p-alkylphenol followed by overbasing to form overbased salicylate detergent. Suitable p-alkylphenols include those with linear and/or branched hydrocarbyl groups of <NUM> to <NUM> carbon atoms. Salicylate detergents may also be prepared by alkylation of salicylic acid, followed by overbasing. Salicylate detergents prepared in this manner, may be prepared from linear and/or branched alkylating agents (usually <NUM>-olefins) containing <NUM> to <NUM> carbon atoms, <NUM> to <NUM> carbon atoms, or <NUM> to <NUM> carbon atoms.

In some embodiments, the overbased metal detergent grease may have a total base number "TBN" of <NUM> to <NUM>, to <NUM> to <NUM>, to <NUM> to <NUM>. The overbased metal detergent may be an overbased metal sulfonate, salicylate, naphthalene, naphthenate, phenate or oleate detergent, or mixtures thereof. In other embodiments, the overbased metal detergent may be present in a range of <NUM> to <NUM>, or <NUM> to <NUM> weight percent based on a total yield of the grease.

In one embodiment, the grease may be a food-grade grease. Suitable greases may include, but are not limited to, greases comprising at least one base oil selected from highly refined mineral oils ("liquid paraffin" or "white oil"), polyalphaolefin, polyalkylene glycol, seed oil, vegetable oil ("esters"). In other embodiments, the grease may comprise an oil of lubricating viscosity selected from at least one API Group I, II, III, IV, or V oil, naphthenic oil, silicone oil, esters, or mixtures thereof.

The greases described herein may also comprise an oil of lubricating viscosity. Such oils include natural and synthetic oils, oil derived from hydrocracking, hydrogenation, and hydrofinishing, unrefined, refined, re-refined oils or mixtures thereof. A more detailed description of unrefined, refined and re-refined oils is provided in <CIT>, paragraphs [<NUM>] to [<NUM>] (a similar disclosure is provided in <CIT>, see [<NUM>] to [<NUM>]). A more detailed description of natural and synthetic lubricating oils is described in paragraphs [<NUM>] to [<NUM>] respectively of <CIT> (a similar disclosure is provided in <CIT>, see [<NUM>] to [<NUM>]). Synthetic oils may also be produced by Fischer-Tropsch reactions and typically may be hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, oils may be prepared by a Fischer-Tropsch gas-to-liquid synthetic procedure as well as other gas-to-liquid oils.

Oils of lubricating viscosity may also be defined as specified in the<NPL>. "Base Stock Categories". In one embodiment the oil of lubricating viscosity may be an API Group II or Group III oil. In one embodiment, the oil of lubricating viscosity may be an API Group I oil.

Exemplary embodiments of grease formulations are shown in Table <NUM> below.

The amount of each chemical component described (including the Grease Additives below) is presented exclusive of any solvent or diluent oil, which may be customarily present in the commercial material, that is, on an active chemical basis, unless otherwise indicated. However, unless otherwise indicated, each chemical or composition referred to herein should be interpreted as being a commercial grade material which may contain the isomers, by-products, derivatives, and other such materials which are normally understood to be present in the commercial grade.

The overbased metal detergent grease disclosed herein may have improved extreme pressure properties compared to a grease not comprising at least one of an acid, polyalkylene glycol, or mixtures thereof. Suitable methods for measuring improved extreme pressure properties include, but are not limited to, ASTM D2596, commonly called "<NUM>-ball weld point". Accordingly, in some embodiments, the grease may have an extreme pressure performance, as measured by the Standard Test Method for Measurement of Extreme-Pressure Properties of Lubricating Grease ("Four-Ball Method") ASTM D2596, of passing, or at least <NUM>-f. In yet another embodiment, the weld point using the Four-Ball Method of the grease may be at least <NUM>-f. In yet other embodiments, the overbased metal detergent grease disclosed herein may have anti-corrosion properties of copper of 1B or better using ASTM D4048. In other embodiments, the grease may have a wear test result of less than or equal to <NUM> using ASTM D2266.

Methods suitable for making the grease are not overly limited and include any method known to persons ordinarily skilled in the art. The grease may be made in a one-step process or a two-step process having a gelation step and a complexing step. If using a two-step process, the polyalkylene glycol and /or an acid having at least one of both a nitrogen and a sulfur atom may be used in the gelation step, the complexing step, or both. Both the polyalkylene glycol and /or an acid having at least one of both a nitrogen and a sulfur atom may be used together in a one-step process.

Upon visual observation, grease color can range from a white or off-white color to a dark brown color, depending on the ingredients used. While color does not in any way affect the performance of the grease, the market generally prefers lighter color greases having a white, off-white, tan, or beige color, and darker greases, such as brown grease are less preferred. The grease compositions disclosed herein have a preferable tan color.

The overbased metal detergent grease disclosed herein may be used to lubricate mechanical components. Accordingly, some embodiments include methods of lubricating a mechanical component using the overbased metal detergent grease described above. The methods may comprise contacting the mechanical component with the grease. Exemplary mechanical components include, but are not limited to, at least one of a gear, drivetrain element, bearing, hinge, or combinations thereof. In another embodiment, a method of improving the extreme pressure performance of an over-based metal sulfonate grease as measured by <NUM>-ball weld point is disclosed.

The grease composition optionally comprises other performance additives. The other performance additives include at least one of metal deactivators (often called corrosion inhibitors), rust inhibitors, viscosity modifiers, detergents, friction modifiers, antiwear agents, dispersants, dispersant viscosity modifiers, extreme pressure agents (in addition to the extreme pressure agents described above), antioxidants, and mixtures thereof. Typically, a fully-formulated grease composition will contain one or more of these performance additives.

The metal deactivators may comprise one or more derivatives of benzotriazole, benzimidazole, <NUM>-alkyldithiobenzimidazoles, <NUM>-alkyldithiobenzothiazoles, <NUM>-(N,N-dialkyldithiocarbamoyl)benzothiazoles, <NUM>,<NUM>-bis(alkyldithio)-<NUM>,<NUM>,<NUM>-thiadiazoles, <NUM>,<NUM>-bis(N,N-dialkyldithiocarbamoyl)-<NUM>,<NUM>,<NUM>-thiadiazoles, <NUM>-alkyldithio-<NUM>-mercaptothiadiazoles or mixtures thereof.

The benzotriazole compounds may include hydrocarbyl substitutions at one or more of the following ring positions <NUM>- or <NUM>- or <NUM>- or <NUM>- or <NUM>- or <NUM>- benzotriazoles. The hydrocarbyl groups may contain from <NUM> to <NUM> carbons, and in one embodiment from <NUM> to <NUM> carbons, and in one embodiment from <NUM> to <NUM> carbons. The metal deactivator may comprise <NUM>-methylbenzotriazole. The metal deactivator may be present in the grease composition at a concentration in the range up to <NUM> wt %, or <NUM> to <NUM> wt %, or <NUM> to <NUM> wt %.

The rust inhibitor may comprise one or more metal sulphonates such as calcium sulphonate or magnesium sulphonate, amine salts of carboxylic acids such as octylamine octanoate, condensation products of dodecenyl succinic acid or anhydride and a fatty acid such as oleic acid with a polyamine, e.g. a polyalkylene polyamine such as triethylenetetramine, or half esters of alkenyl succinic acids in which the alkenyl group contains from <NUM> to <NUM> carbon atoms with alcohols such as polyglycols.

The rust inhibitors may present in the grease composition at a concentration in the range up to <NUM> wt %, and in one embodiment in the range from <NUM> wt % to <NUM> wt %, and in one embodiment in the range from <NUM> wt % to <NUM> wt %.

Antioxidants include diarylamine alkylated diarylamines, hindered phenols, dithiocarbamates, <NUM>,<NUM>-dihydro-<NUM>,<NUM>,<NUM>-trimethylquinoline, hydroxyl thioethers, or mixtures thereof. In one embodiment the grease composition includes an antioxidant, or mixtures thereof. The antioxidant may be present at <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt % of the grease composition.

The diarylamine alkylated diarylamine may be a phenyl-α-naphthylamine (PANA), an alkylated diphenylamine, or an alkylated phenylnapthylamine, or mixtures thereof. The alkylated diphenylamine may include di-nonylated diphenylamine, nonyl diphenylamine, octyl diphenylamine, di-octylated diphenylamine, or di-decylated diphenylamine. The alkylated diarylamine may include octyl, di-octyl, nonyl, di-nonyl, decyl or di-decyl phenylnapthylamines. In one embodiment the alkylated diphenylamine may comprise at least one of octylated diphenylamine, butylated diphenylamine, or mixtures thereof e.g. Irganox® L <NUM> from BASF.

The hindered phenol antioxidant often contains a secondary butyl and/or a tertiary butyl group as a sterically hindering group. The phenol group may be further substituted with a hydrocarbyl group (typically linear or branched alkyl) and/or a bridging group linking to a second aromatic group. The bridging atom may be carbon or sulfur. Examples of suitable hindered phenol antioxidants include <NUM>,<NUM>-di-tertbutylphenol, <NUM>-methyl-<NUM>,<NUM>-di-tert-butylphenol, <NUM>-ethyl-<NUM>,<NUM>-di-tert-butylphenol, <NUM>-propyl-<NUM>,<NUM>-di-tert-butylphenol or <NUM>-butyl-<NUM>,<NUM>-di-tert-butylphenol, or <NUM>-dodecyl-<NUM>,<NUM>-di-tert-butylphenol. In one embodiment the hindered phenol antioxidant may be an ester and may include, e.g., Irganox® L <NUM> from BASF. A more detailed description of suitable ester-containing hindered phenol antioxidant chemistry is found in <CIT>.

The dithiocarbamate anti-oxidant may be metal containing such as molybdenum or zinc dithiocarbamate or it may be "ashless". Ashless refers to the dithiocarbamate as containing no metal and the linking group is typically a methylene group.

The <NUM>,<NUM>-dihydro-<NUM>,<NUM>,<NUM>-trimethylquinoline may be present as a unique molecule or oligomerized with up to <NUM> repeat units and known commercially as "Resin D", available form a number of suppliers.

In one embodiment the grease composition further includes a viscosity modifier. The viscosity modifier is known in the art and may include hydrogenated styrene-butadiene rubbers, ethylene-propylene copolymers, polymethacrylates, polyacrylates, hydrogenated styrene-isoprene polymers, hydrogenated diene polymers, polyalkyl styrenes, polyolefins, esters of maleic anhydride-olefin copolymers (such as those described in International Application <CIT>), esters of maleic anhydride-styrene copolymers, or mixtures thereof.

Some polymers may also be described as dispersant viscosity modifiers (often referred to as DVM) because they exhibit dispersant properties. Polymers of this type include olefins, for example, ethylene propylene copolymers that have been functionalized by reaction with maleic anhydride and an amine. Another type of polymer that may be used is polymethacrylate functionalized with an amine (this type may also be made by incorporating a nitrogen containing co-monomer in a methacrylate polymerization). More detailed description of dispersant viscosity modifiers are disclosed in International Publication <CIT> or <CIT>; <CIT>; <CIT>; and <CIT>. The viscosity modifiers may be present at <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt %, or <NUM> wt % to <NUM> wt % of the grease composition.

The grease composition may further include a dispersant, or mixtures thereof. The dispersant may be a succinimide dispersant, a Mannich dispersant, a succinamide dispersant, a polyolefin succinic acid ester, amide, or ester-amide, or mixtures thereof. In one embodiment the dispersant may be present as a single dispersant. In one embodiment the dispersant may be present as a mixture of two or three different dispersants, wherein at least one may be a succinimide dispersant.

The dispersant may be an N-substituted long chain alkenyl succinimide. An example of an N-substituted long chain alkenyl succinimide is polyisobutylene succinimide. Typically, the polyisobutylene from which polyisobutylene succinic anhydride is derived has a number average molecular weight of <NUM> to <NUM>, or <NUM> to <NUM> or <NUM> to <NUM>. Succinimide dispersants and their preparation are disclosed, for instance in <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>,<CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>, <CIT> and <CIT>.

The dispersants may also be post-treated by conventional methods by a reaction with any of a variety of agents. Among these are boron compounds (such as boric acid), urea, thiourea, dimercaptothiadiazoles, carbon disulphide, aldehydes, ketones, carboxylic acids such as terephthalic acid, hydrocarbon-substituted succinic anhydrides, maleic anhydride, nitriles, epoxides, and phosphorus compounds. In one embodiment the post-treated dispersant is borated. In one embodiment the post-treated dispersant is reacted with dimercaptothiadiazoles. In one embodiment the post-treated dispersant is reacted with phosphoric or phosphorous acid.

Typically, the additional antiwear agent may be a phosphorus antiwear agent. The antiwear agent may be present at <NUM> wt % to <NUM> wt %, <NUM> wt % to <NUM> wt %, <NUM> wt % to <NUM> wt % of the lubricant. The phosphorus antiwear agent may include a phosphorus amine salt, calcium salt, or mixtures thereof. The phosphorus amine salt includes an amine salt of a phosphorus acid ester or mixtures thereof. The amine salt of a phosphorus acid ester includes phosphoric acid esters and amine salts thereof; dialkyldithiophosphoric acid esters and amine salts thereof; phosphites; and amine salts of phosphorus-containing carboxylic esters, ethers, and amides; hydroxy substituted di or tri esters of phosphoric or thiophosphoric acid and amine salts thereof; phosphorylated hydroxy substituted di or tri esters of phosphoric or thiophosphoric acid and amine salts thereof; and mixtures thereof. In one embodiment the oil soluble phosphorus amine salt includes partial amine salt-partial metal salt compounds or mixtures thereof. In one embodiment the phosphorus compound further includes a sulphur atom in the molecule. In another embodiment the phosphorus compound is a derivative of calcium.

Additional examples of the antiwear agent may include a non-ionic phosphorus compound (typically compounds having phosphorus atoms with an oxidation state of +<NUM> or +<NUM>). In one embodiment the amine salt of the phosphorus compound may be ashless, i.e., metal-free (prior to being mixed with other components).

In one embodiment, the antiwear additives may include a zinc dialkyldithiophosphate. In other embodiments the grease is substantially free of, or even completely free of zinc dialkyldithiophosphate. In yet another embodiment, the grease includes a dithiocarbamate antiwear agent defined in <CIT> column <NUM>, line <NUM> to column <NUM>, line <NUM>. When present the dithiocarbamate antiwear agent may be present from <NUM> wt %, <NUM> wt %, <NUM> wt % or even <NUM> wt % up to <NUM> wt %, <NUM> wt %, <NUM> wt % or even <NUM> wt % in the overall composition.

Grease additive packages may include the compositions in Table <NUM> below.

In order to demonstrate improved performance in a grease composition, the composition may be evaluated versus control standards as to ASTM D2266-<NUM> (<NUM>): Standard Test Method for Wear Preventive Characteristics of Lubricating Grease (Four-Ball Method), ASTM D4170-<NUM>: Standard Test Method for Fretting Wear Protection by Lubricating Greases, ASTM D5969-11e: Standard Test Method for Corrosion-Preventive Properties of Lubricating Greases in Presence of Dilute Synthetic Sea Water Environments and ASTM D6138-<NUM>: Standard Test Method for Determination of Corrosion-Preventive Properties of Lubricating Greases Under Dynamic Wet Conditions (Emcor Test).

It is known that some of the materials described above may interact in the final formulation, so that the components of the final formulation may be different from those that are initially added. For instance, metal ions (of, e.g., a detergent) can migrate to other acidic or anionic sites of other molecules. The products formed thereby, including the products formed upon employing the composition of the present invention in its intended use, may not be susceptible of easy description. Nevertheless, all such modifications and reaction products are included within the scope of the present invention; the present invention encompasses the composition prepared by admixing the components described above.

For the Control, <NUM> grams of overbased calcium sulfonate, <NUM> grams of <NUM> SUS viscosity oil ("Formulated Oil"), <NUM> grams of detergent dodecyl benzene sulfonic acid, <NUM> grams of acetic acid and <NUM> grams of hexylene glycol are added to a reactor. The mixture is mixed and heated to <NUM> to <NUM> and held at temperature for one hour. Complete conversion of amorphous calcium carbonate to calcite is verified by infrared. Once conversion is complete, <NUM> grams of hydrated lime in <NUM> grams of water and <NUM> grams of boric acid in <NUM> grams of water are added. The mixture is then heated and mixed slowly to <NUM> until all volatiles are stripped off. Then, <NUM> grams of <NUM>-hydroxystearic acid is added and mixed while holding the temperature to <NUM> to <NUM> until all the <NUM>-hydroxystearic acid is complexed. The mixture is then cooled to <NUM> to <NUM> followed by the addition of <NUM> grams of an antioxidant. The mixture is then cooled and adjusted to Grade <NUM> with <NUM> SUS oil and milled to prepare the finished grease.

For Comp <NUM>, <NUM> grams of overbased calcium sulfonate, <NUM> grams of <NUM> SUS viscosity oil ("Formulated Oil"), <NUM> grams of sulfamic acid ("Promotor B"), <NUM> grams of detergent dodecyl benzene sulfonic acid, <NUM> grams of acetic acid and <NUM> grams of hexylene glycol are added to a reactor. The mixture is mixed and heated to <NUM> to <NUM> and held at temperature for one hour. Complete conversion of amorphous calcium carbonate to calcite is verified by infrared. Once conversion is complete, <NUM> grams of hydrated lime in <NUM> grams of water, <NUM> grams of boric acid in <NUM> grams of water are added. The mixture is then heated and mixed slowly to <NUM> until all volatiles are stripped off. Then, <NUM> grams of <NUM>-hydroxystearic acid is added and mixed while holding the temperature to <NUM> to <NUM> until all the <NUM>-hydroxystearic acid is complexed. The mixture is then cooled to <NUM> to <NUM> followed by the addition of <NUM> grams of an antioxidant. The mixture is then cooled and adjusted to Grade <NUM> with <NUM> SUS oil and milled to prepare the finished grease.

First, <NUM> grams of overbased calcium sulfonate, <NUM> grams of <NUM> SUS viscosity oil ("Formulated Oil"), <NUM> grams of methoxypolyethylene glycol ("Promotor A"), <NUM> grams of detergent dodecyl benzene sulfonic acid, <NUM> grams of acetic acid and <NUM> grams of hexylene glycol are added to a reactor. The mixture is mixed and heated to <NUM> to <NUM> and held at temperature for one hour. Complete conversion of amorphous calcium carbonate to calcite is verified by infrared. Once conversion is complete, <NUM> grams of hydrated lime in <NUM> grams of water, <NUM> grams of boric acid in <NUM> grams of water, <NUM> grams of methoxypolyethylene glycol ("Promotor A") are added. The mixture is then heated and mixed slowly to <NUM> until all volatiles are stripped off. Then, <NUM> grams of <NUM>-hydroxystearic acid is added and mixed while holding the temperature to <NUM> to <NUM> until all the <NUM>-hydroxystearic acid is complexed. The mixture is then cooled to <NUM> to <NUM> followed by the addition of <NUM> grams of an antioxidant. The mixture is then cooled and adjusted to Grade <NUM> with <NUM> SUS oil and milled to prepare the finished grease.

For EX <NUM>, <NUM> grams of overbased calcium sulfonate, <NUM> grams of <NUM> SUS viscosity oil ("Formulated Oil"), <NUM> grams of methoxypolyethylene glycol ("Promotor A"), <NUM> grams of detergent dodecyl benzene sulfonic acid, <NUM> grams of acetic acid, and <NUM> grams of hexylene glycol are added to a reactor. The mixture is mixed and heated to <NUM> to <NUM> and held at temperature for one hour. Complete conversion of amorphous calcium carbonate to calcite is verified by infrared. Once conversion is complete, <NUM> grams of hydrated lime in <NUM> grams of water, <NUM> grams of boric acid in <NUM> grams of water are added. To this mixture, <NUM> grams of sulfamic acid ("Promotor B") and another <NUM> grams of methoxypolyethylene glycol ("Promotor A") are added. The mixture is then heated and mixed slowly to <NUM> until all volatiles are stripped off. Then, <NUM> grams of <NUM>-hydroxystearic acid is added and mixed while holding the temperature to <NUM> to <NUM> until all the <NUM>-hydroxystearic acid is complexed. The mixture is then cooled to <NUM> to <NUM> followed by the addition of <NUM> grams of an antioxidant. The mixture is then cooled and adjusted to Grade <NUM> with <NUM> SUS oil and milled to prepare the finished grease.

EX <NUM> is similar to EX2, except different amounts of hexylene glycol and hydrated lime are used in the complexing step. First, <NUM> grams of overbased calcium sulfonate, <NUM> grams of <NUM> SUS viscosity oil ("Formulated Oil"), <NUM> grams of methoxypolyethylene glycol ("Promotor A"), <NUM> grams of detergent dodecyl benzene sulfonic acid, <NUM> grams of acetic acid and <NUM> grams of hexylene glycol are added to a reactor. The mixture is mixed and heated to <NUM> to <NUM> and held at temperature for one hour. Complete conversion of amorphous calcium carbonate to calcite is verified by infrared. Once conversion is complete, <NUM> grams of hydrated lime in <NUM> grams of water and <NUM> grams of boric acid in <NUM> grams of water are added. To this mixture, <NUM> grams of sulfamic acid ("Promotor B") and another <NUM> grams of methoxypolyethylene glycol ("Promotor A") are added. The mixture is then heated and mixed slowly to <NUM> until all volatiles are stripped off. Then, <NUM> grams of <NUM>-hydroxystearic acid is added and mixed while holding the temperature to <NUM> to <NUM> until all the <NUM>-hydroxystearic acid is complexed. The mixture is then cooled to <NUM> to <NUM> followed by the addition of <NUM> grams of an antioxidant. The mixture is then cooled and adjusted to Grade <NUM> with <NUM> SUS oil and milled to prepare the finished grease.

EX <NUM> is similar to EX3, except different amounts of acetic acid and hydrated lime are used in the complexing step. First, <NUM> grams of overbased calcium sulfonate, <NUM> grams of <NUM> SUS viscosity oil ("Formulated Oil"), <NUM> grams of methoxypolyethylene glycol ("Promotor A"), <NUM> grams of detergent dodecyl benzene sulfonic acid, <NUM> grams of acetic acid and <NUM> grams of hexylene glycol are added to a reactor. The mixture is mixed and heated to <NUM> to <NUM> and held at temperature for one hour. Complete conversion of amorphous calcium carbonate to calcite is verified by infrared. Once conversion is complete, <NUM> grams of hydrated lime in <NUM> grams of water and <NUM> grams of boric acid in <NUM> grams of water are added. To this mixture, <NUM> grams of sulfamic acid ("Promotor B") and another <NUM> grams of methoxypolyethylene glycol ("Promotor A") are added. The mixture is then heated and mixed slowly to <NUM> until all volatiles are stripped off. Then, <NUM> grams of <NUM>-hydroxystearic acid is added and mixed while holding the temperature to <NUM> to <NUM> until all the <NUM>-hydroxystearic acid is complexed. The mixture is then cooled to <NUM> to <NUM> followed by the addition of <NUM> grams of an antioxidant. The mixture is then cooled and adjusted to Grade <NUM> and milled to prepare the finished grease.

The above examples were checked for <NUM>-ball extreme pressure ("EP") ASTM D2596 and wear ASTM D2266.

Claim 1:
An overbased metal detergent grease comprising a polyalkylene glycol wherein the polyalkylene glycol is a methoxypolyethylene glycol having a number average (Mn) molecular weight of <NUM> to <NUM>n, <NUM> to <NUM>n, or <NUM> to <NUM>n, wherein the grease is made in a two-step process having a gelation step and a complexing step, wherein the polyalkylene glycol is added as a promotor during the gelation step.