CN110088255A

CN110088255A - The lubrication of the automatic transmission of abrasion with the reduction on needle bearing

Info

Publication number: CN110088255A
Application number: CN201780077263.4A
Authority: CN
Inventors: W·D·亚伯拉罕; 石崎敬太
Original assignee: Lubrizol Corp
Current assignee: Lubrizol Corp
Priority date: 2016-12-16
Filing date: 2017-12-14
Publication date: 2019-08-02
Also published as: US20200080017A1; WO2018112135A1; EP3555252A1; JP7145857B2; JP2020502318A; CA3045129A1; EP3555252B1

Abstract

Lubricant compositions are 2.2-3.7mm comprising the kinematic viscosity of (a) at 100 DEG C²The oil of/s；At least one borate with the alkyl with 4-18 carbon atom provides 25-150 weight ppm boron in an amount of to composition；(c) at least one phosphorus ester, content is provides 150-650 weight ppm phosphorus to composition, and wherein kinematic viscosity of the lubricant compositions at 100 DEG C is less than or equal to 4.7mm²/ s provides wearability for the needle bearing in automatic transmission.

Description

Lubrication of automatic transmission with reduced wear on needle bearings

Background

The disclosed technology relates to lubricant formulations that provide good wear resistance. They may be particularly useful when used to lubricate needle bearings in automatic transmissions.

U.S. publication 2007/0142237, Degonia et al, 21.6.2007 discloses a lubricant composition, such as a gear oil. It contains a base oil, typically having a viscosity of 2-15 or 2-10 cSt. It also contains a boron-containing compound, which may be a nitrogen-containing compound such as a succinimide or a borate or an amide, such as a borated epoxide or a borated glycerol fatty acid ester. The amount of boron compound may provide 5-500 or 11-100ppm B. Also present are sulfur-containing, phosphorus-containing compounds; dibutyl phosphonates are disclosed.

U.S. publication 2014/0031268, Sumiejski et al, 30/1/2014, discloses a lubricant for a continuously variable transmission. The lubricant comprises a functionalized dispersant treated with a (inter alia) borating agent; di-C3-C6 alkyl phosphites and trialkylborates. The lubricant composition may have up to about 12mm²KV100 in/s, for example 2-10 or 6-8. The dispersant may contain 0.4 to 1.2% by weight of boron from the borating agent.

U.S. publication 2014/0107001, Saccomando et al, 4.17.2014, discloses a lubricant for automatic transmissions that contains certain aromatic condensation products. It is 1 or 2-8 to 10mm in KV100²Is prepared in oil, and the entire lubricant composition may have a thickness of 1 or 1.5 to 10 or to 15 or to 20mm²KV 100/s. Other components that may be present include dispersants. Succinimide dispersants and dispersants post-treated with, for example, boron compounds are disclosed. Supplemental friction modifiers may be present, such as fatty phosphites, borated fatty epoxides, or borated glycerol fatty acids. One formulation contains 0.15% borate friction modifier and 0.30% phosphite and phosphonate friction modifiers. Another formulation contains 0.2% phosphite friction modifier.

U.S. publication 2015/0376544, kakakakakao et al, 31.12.2015, discloses a lubricating composition for a transmission comprising a lubricant base oil having a kinematic viscosity at 100 ℃ of 1.5mm in an amount of 50 to 97 mass% based on the mass of the total base oil composition²(s) or more and 3.5mm²A mineral base oil in an amount of 3 to 10 mass% and having a kinematic viscosity at 100 ℃ of 2 to 10mm²Monoester-based oils per second; and phosphate-containing and borated ashless dispersants.

U.S. publication 2016/0130524, advanced, 5/12/2016, discloses a low viscosity ester lubricant, such as a crankcase lubricant, for high temperature applications. The esters have KV100 of 1-4 centistokes. The lubricant optionally contains one or more dispersants, among which are alkyl succinic acid derivatives. These products may be post-treated with various agents including, inter alia, boron compounds such as borate esters. In one example, a low Zn dialkyldithiophosphate is present.

U.S. publication 2016/0108337 to Abraham et al, 2016, 4, 21 discloses lubricant compositions and methods of lubricating a transmission. The kinematic viscosity of the lubricating composition at 100 ℃ may be from 3.6 to 4.8cSt or from 4.0 to 4.2 cSt. It may comprise an oil of lubricating viscosity 2.8 to 3.6 cSt. The lubricant contains 1.2-5.0% of a borated dispersant and two phosphorus-containing compounds in an amount to provide 360-950ppm phosphorus. The reaction product (i.e., borated dispersant) may contain 0.2 to 0.6 weight percent boron. An optional component is a friction modifier; including borated glycerides and borated fatty epoxides.

U.S. Pat. No. 9,090,850, Edwards et al, 2015, 7/28, discloses a lubricant containing a dithiophosphate ester of the structure

It may optionally contain a phosphite antiwear agent. It may optionally contain one or more boron-containing compounds, examples of which include borate esters and borated succinimide dispersants. The lubricant composition may have a viscosity of 2 to 30cSt or 4 to 8cSt at 100 ℃.

Thus, the disclosed technology addresses the problem of providing good or improved bearing life or reduced bearing wear, for example in needle bearings, particularly when very low viscosity lubricant fluids are used.

Abstract

The disclosed technology provides a lubricant composition comprising: (a) kinematic viscosity at 100 ℃ of about 2.2 to about 3.7mm²Oil per second; (b) at least one borate ester having an alkyl group having from 4 to about 18 carbon atoms in an amount to provide 25 to 300, or 30 to 150, or 50 to 100ppm by weight boron to the composition; (c) at least one phosphorus-containing ester in an amount to provide from about 150 to about 650 ppm by weight phosphorus to the composition; wherein the lubricant composition has a kinematic viscosity at 100 ℃ of less than or equal to about 4.7mm²/s。

In another embodiment, the disclosed technology provides a lubricant composition comprising: (a) about 50 to about 98 weight percent of an oil having a kinematic viscosity at 100 ℃ of about 2.2 to about 3.7mm²S; (b-1) about 0.1 to about 1.0 wt.% of a C4-C12 alkyl-containing polymerA borate ester of (a); (b-2) from about 0.15 to about 0.40 weight percent of a borate ester comprising a C14 to about C18 alkyl group; (c) at least one phosphorus-containing ester in an amount to provide from about 150 to about 650 ppm by weight phosphorus to the composition; (e-1) about 0.25 to 4.0 or 1.0 to about 4.0 weight percent of a borated succinimide dispersant that is not treated with dimercaptothiadiazole; (e-2) about 0.1 to about 1.5 weight percent of a borated succinimide dispersant treated with a dimercaptothiadiazole; wherein components (b-1), (b-2), (e-1) and (e-2) provide boron in an amount of at least 180ppm by weight of the composition; wherein the lubricant composition has a kinematic viscosity at 100 ℃ of less than or equal to about 4.7mm²/s。

The disclosed technology also provides for the use of such compositions in lubricating an automatic transmission.

Detailed Description

Various preferred features and embodiments will be described below by way of non-limiting illustration.

One component of the disclosed technology isOil of lubricating viscosityAlso known as base oils. The Base Oil may be selected from any of the group I-V Base oils of the American Petroleum Institute (API) Base Oil interconversion Guidelines (2011), i.e., Base oils

Other recognized base oil classes can be used, even if the API is not formally determined, group II + refers to group II materials having a viscosity index of 110-119 and a lower volatility than other group II oils, and group III + refers to group III materials having a viscosity index of greater than or equal to 130.

Oils of lubricating viscosity (or mixtures of such oils)Material) is a relatively low viscosity oil with a kinematic viscosity at 100 ℃ of 2.2-3.7mm²S, or 2.5 to 3.5mm²S, or 2.8 to 3.3mm²And s. Using oils of this viscosity range lubricant compositions can be prepared having a kinematic viscosity at 100 ℃ of less than or equal to 4.7mm²S, for example 3.0 to 4.6 or 3.3 to 4.3 or 3.6 to 4.1mm²/s

The amount of oil of lubricating viscosity may be from 50 to 98 wt%, or from 60 to 96, or from 70 to 94, or from 80 to 93, or from 85 to 92 wt%. The amount may be calculated to include the amount of diluent oil conventionally provided with additive components such as detergents, dispersants and viscosity modifiers.

Another component of the disclosed lubricant compositions is at least one having an alkyl group having from 4 to 18 carbon atomsBoron Acid esters. In certain embodiments, two alkyl groups may be present, one having 4 to 12 or 4 to 10 or 6 to 10 carbon atoms and the other having 14 to 18 carbon atoms. Boronic esters can generally be considered as esters of boronic acids or their equivalents with alcohols, although they need not be formed by esterification (condensation) reactions. In one embodiment, the borate ester may be a so-called borated epoxide.

In one embodiment, the boron-containing compound may be described as a borate ester or borate alcohol. The borate or borate alcohol compounds are essentially the same except that the borate alcohol has at least one unesterified hydroxyl group, which may also be a borated epoxide. Thus, as used herein, the term "borate" is used to refer to a borate or borate alcohol.

The borate ester may be prepared by the reaction of a boron compound and at least one compound selected from the group consisting of epoxy compounds, halohydrin compounds, epihalohydrin compounds, alcohols, and mixtures thereof. Alcohols include diols, triols, or higher alcohols, provided that for one embodiment the hydroxyl groups are on adjacent carbon atoms, i.e., ortho. Hereinafter, when referring to an epoxy compound, a halohydrin compound, an epihalohydrin compound, or a mixture thereof, "epoxy compound" is used.

Is suitable for preparing boronThe boron compounds of the acid esters include various forms, such as boric acid (including metaboric acid HBO)₂Orthoboric acid H₃BO₃And tetraboric acid H₂B₄O₇) Boron oxide, boron trioxide and alkyl borates. Borate esters may also be prepared from boron halides.

In one embodiment, the borate ester is formed by the reaction of a boron compound with an epoxy compound, a diol, a triol, or a higher alcohol. The borate ester may be represented by at least one of formulas (I) - (VI):

wherein each R may be hydrogen or a hydrocarbyl group, provided that the borate ester is oil soluble.

In one embodiment, at least two R groups in each of the above formulae are hydrocarbyl groups. The hydrocarbyl group may be alkyl, aryl or cycloalkyl, where any two adjacent R groups are joined in a ring. When R is an alkyl group, the group may be saturated or unsaturated. In one embodiment, the hydrocarbyl group is an unsaturated alkyl group. In one embodiment, the hydrocarbyl group is cyclic. In one embodiment, the hydrocarbyl group is a mixture of alkyl and cycloalkyl groups.

The number of carbon atoms present in each R may be 4 to 18 or 6 to 12. In certain embodiments, the total number of carbon atoms on the R group may generally be 9 or more, or about 10 or more, or about 12 or more, or about 14 or more.

Examples of R groups include isopropyl, n-butyl, isobutyl, pentyl, 2-pentenyl, 4-methyl-2-pentyl, 2-ethylhexyl, heptyl, isooctyl, nonyl, decyl, undecyl, dodecenyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl and octadecyl.

Epoxy compounds useful in the preparation of boronic esters (i.e., for preparing materials also known as borated epoxides) can be represented by formula (VIIa) or (VIIb):

wherein,

R¹independently H or an alkyl chain containing 1 to 4 or 1 to 2 carbon atoms;

R²is an alkyl chain containing from 4 to 18, or from 6 to 16, or from 8 to 14 carbon atoms; and

t is independently hydrogen or halogen, such as chlorine, bromine, iodine or fluorine or mixtures thereof. In one embodiment, T is chloro; in another embodiment, T is hydrogen.

In one embodiment, the epoxy compound of the present invention comprises C₁₄-C₁₆Epoxide or C₁₄-C₁₈Commercial mixtures of epoxides. In one embodiment, the epoxy compounds of the present invention have been purified. Examples of suitable purified epoxy compounds may include 1, 2-epoxydecane, 1, 2-epoxyundecane, 1, 2-epoxydodecane, 1, 2-epoxytridecane, 1, 2-epoxytetradecane, 1, 2-epoxypentadecane, 1, 2-epoxyhexadecane, 1, 2-epoxyheptadecane, and 1, 2-epoxyoctadecane. In one embodiment, the purified epoxy compound comprises 1, 2-epoxyhexadecane. In one embodiment, the borate ester comprises a borated epoxide having 12 to 18 or 14 to 18 carbon atoms.

The alcohol used for esterification of the alcohol with the borating agent may include monohydric, dihydric, trihydric or higher alcohols. The alcohol may contain 4 to 18 carbon atoms or 6 to 16 or 6 to 12 carbon atoms.

The borate ester may be prepared by blending the boron compound and the above epoxy compound or alcohol and heating them at a suitable temperature, such as 80 ℃ to 250 ℃, 90 ℃ to 240 ℃, or 100 ℃ to 230 ℃ until the desired reaction occurs. The molar ratio of boron compound to epoxy compound may be 4:1 to 1:4, or 1:1 to 1:3, or about 1:2. Inert liquids may be used to carry out the reaction, such as toluene, xylene, chlorobenzene, dimethylformamide or mixtures thereof. Water is generally formed and distilled off during the condensation reaction. An alkaline reagent may be used to catalyze the reaction.

In one embodiment, suitable borate compounds include tripropyl borate, tributyl borate, tripentyl borate, trihexyl borate, triheptyl borate, trioctyl borate, trinonyl borate, and tridecyl borate. In one embodiment, the borate compound comprises tributyl borate, tri-2-ethylhexyl borate, or a mixture thereof.

In certain embodiments, the lubricant composition may comprise a borate ester comprising an alkyl group having 4 to 12 carbon atoms and a borate ester comprising an alkyl group having 12 to 18 or 14 to 18 carbon atoms. In other embodiments, the borate ester component may comprise the reaction product of boric acid and an alcohol having from 6 to 12 carbon atoms. In other embodiments, the borate ester component may comprise a borated epoxide having 12 to 18 carbon atoms.

The amount of borate ester in the lubricant may be 0.1 to 1.1 wt% or 0.05 to 1.1 or 0.15 to 0.7 or 0.10 or 0.90 wt%, or 0.2 to 1.0 wt% or 0.25 to 0.75 wt%. If two borates are present, one having C4-C12 alkyl and one having C14-C18 alkyl, the amount of C4-C12 ester may be 0.05-1.0% by weight or 0.1-1, or 0.15-0.7 or 0.2-0.6%; the C14-C18 ester can be 0.05-1 wt%, or 0.075-0.7, or 0.1-0.4 wt%. The one or more borate esters contribute to the amount of boron in the lubricant, some of which may come from other sources, such as borated dispersants (discussed below). The total amount of boron in the lubricant composition may be 100-500 ppm by weight or 150-400, or 200-350 ppm by weight, and the amount contributed by the borate may be 25-300, or 30-150, or 50-100, or 70-100 ppm by weight. The balance of boron may be provided by other sources, such as the borated dispersants described below.

Lubrication of the disclosed technologyThe agent also comprises at least onePhosphorus-containing estersIn an amount to provide 150-650, or 150-350, or 180-250 ppm phosphorus to the composition. The at least one phosphorus-containing ester is present in an amount of 0.05 to 0.4 wt%, or 0.1 to 0.35%.

Phosphorus-containing esters may include C4-C8 or C4-C6 alkyl phosphites, such as dioctyl phosphite, or oligomeric phosphites, which are the reaction product of monomeric phosphorous acid or ester with an alkylene glycol.

The C4-C6 alkyl phosphites may include dialkyl phosphites, such as dibutyl phosphite, dihexyl phosphite, and dicyclohexyl phosphite. These materials are readily commercially available.

Oligomeric phosphites are described in more detail in PCT publication WO2016/089565, Abraham et al (Lubrizol), 2016, 6/9. Briefly, they can be described as the reaction product of (a) monomeric phosphorous acid or an ester thereof with (b) at least two alkylene glycols. The first alkylene glycol (i) has two hydroxyl groups in a 1,4 or 1,5 or 1,6 relationship in the carbon chain and the second alkylene glycol (ii) is an alkyl substituted 1, 3-propylene glycol having one or more alkyl substituents on one or more carbon atoms of the propylene unit. The total number of carbon atoms in the alkyl substituted 1, 3-propylene glycol is from 5 to 12. In the oligomeric phosphite, the relative molar amounts of the total amounts of monomeric phosphorous acid or ester thereof (a) and alkylene glycol (b) are typically in a ratio of from about 0.9:1.1 to about 1.1: 0.9. Furthermore, the relative molar amounts of the first alkylene glycol (i) and the alkyl-substituted 1, 3-propylene glycol (ii) are typically in a ratio of from 30:70 to 65:35, or from 35:54 to 60:40 or from 50:60 to 50:50, or from 40:60 to 45: 55.

The first alkylene glycol may be branched (e.g., alkyl substituted) or unbranched, in one embodiment unbranched.unbranched, i.e., linear diols (α, omega-diols) include 1, 4-butanediol, 1, 5-pentanediol and 1, 6-hexanediol. branched or substituted diols include 1, 4-pentanediol, 2-methyl-1, 5-pentanediol, 3, 3-dimethyl-1, 5-pentanediol, 1, 5-hexanediol, 2, 5-hexanediol and 2, 5-dimethyl-2, 5-hexanediol. for purposes of the disclosed technology, diols having one or more secondary hydroxyl groups (e.g., 2, 5-hexanediol) may be referred to as branched or substituted diols, even though the hydroxyl groups themselves may be linear at the 1,4-, 1, 5-or 1, 6-positions (i.e., positions opposite or pendant to each other) may contribute to oligomerization with the phosphorus species without sterically forming a ring structure (in certain embodiments).

The first alkylene dihydroxy compound (diol) may, if desired, have additional hydroxyl groups, i.e., more than 2 per molecule, or there may be exactly two. In one embodiment, there are exactly two hydroxyl groups per molecule. If more than two hydroxyl groups are present care should be taken to ensure that there is no excess cyclization, e.g. that polymerization may be disturbed if less than 4 atoms separate any hydroxyl groups. Furthermore, care should be taken to avoid excessive branching or crosslinking in the product, which may lead to undesirable gel formation. These problems can be avoided by careful control of the reaction conditions, such as control of the ratio of reagents and their order of addition, carrying out the reaction under appropriate dilution conditions, and reaction under low acid conditions. These conditions can be determined by the person skilled in the art by means of only routine experiments.

The second alkylene glycol is an alkyl-substituted 1, 3-propylene glycol having one or more alkyl substituents on one or more carbon atoms of the propylene unit, the total number of carbon atoms in the alkyl-substituted 1, 3-propylene glycol being from 5 to 12 or from 6 to 12 or from 7 to 11 or from 8 to 18, or, in certain embodiments, 9. That is, the alkyl-substituted 1, 3-propylene glycol can be represented by the following general formula

Wherein each R group may be the same or different and may be hydrogen or alkyl, provided that at least one R is alkyl and the total number of carbon atoms in the R group is 2 to 9 or 3 to 9, such that the total carbon atoms in the diol are 5 to 12 or 6 to 12, respectively, and so on for other ranges of total carbon. Similar to the 1,4-, 1, 5-or 1, 6-diols mentioned above, reference herein to a 1, 3-diol means that the two hydroxyl groups are in a 1, 3-relationship to each other, that is, separated by a chain having 3 carbon atoms. Thus, a 1, 3-diol may also be referred to as a 2, 4-or 3, 5-diol. If the 1, 3-diol has one or more secondary hydroxyl groups, such a molecule will be considered a substituted diol. In one embodiment, the number of alkyl substituents is 2 and the total number of carbon atoms in the molecule is 9. Suitable substituents may include, for example, methyl, ethyl, propyl and butyl (in their various possible isomers).

Examples of the second alkylene glycol may include 2, 2-dimethyl-1, 3-propylene glycol, 2-ethyl-2-butylpropane-1, 3-diol, 2-ethylhexane-1, 3-diol, 2, 2-dibutylpropane-1, 3-diol, 2, 2-diisobutylpropane-1, 3-diol, 2-methyl-2-propylpropane-1, 3-diol, 2-propyl-propane-1, 3-diol, 2-butylpropane-1, 3-diol, 2-pentylpropane-1, 3-diol, 2-methyl-2-propylpropane-1, 3-diol, 2, 2-diethylpropane-1, 3-diol, 2,2, 4-trimethylpentane-1, 3-diol, 2-methylpentane-2, 4-diol, 2, 4-dimethyl-2, 4-pentanediol and 2, 4-hexanediol. It should be noted that some of the foregoing nomenclature emphasizes the propane-1, 3-diol structure of the molecule for clarity. For example, 2-pentylpropane-1, 3-diol may also be referred to as 2-hydroxymethylheptan-1-ol, but the latter nomenclature does not so clearly describe the 1, 3-nature of the diol.

While the one or more phosphorus-containing esters will provide phosphorus to the lubricant composition as described above, the total amount of phosphorus in the lubricant may be in a higher range, such as 150-1000, or 200-800 ppm by weight. The additional phosphorus may be provided by a different phosphorus-containing species, for example an inorganic phosphoric acid, such as phosphoric acid or phosphorous acid. Phosphoric acid is commercially available as 85% by weight composition and 15% water, and appropriate amounts thereof may be used. Other phosphorus sources may include phosphorus treated (phosphorus containing) dispersants such as post-treated succinimide dispersants described below.

In certain embodiments, the lubricant compositions of the disclosed technology may further compriseViscosity improverAlso known as viscosity index modifiers or viscosity index improvers. Viscosity Modifier (VM) and dispersantExamples of VM and DVM may include polymethacrylates, polyacrylates, polyolefins, hydrogenated vinyl aromatic-diene copolymers (e.g., styrene-butadiene, styrene-isoprene), styrene-maleate copolymers, and similar polymeric materials, including homopolymers, copolymers, and graft copolymers, including polymers having a linear, branched, or star structure.

Examples of commercially available VMs, DVMs, and chemical types thereof may include the following: polyisobutenes (e.g. Indopol from BP Amoco)^TMOr Parapol of ExxonMobil^TM) (ii) a Olefin copolymers (e.g. of Lubrizol7060. 7065 and 7067, andHC-2000L, HC-1100 and HC-600); hydrogenated styrene-diene copolymers (e.g. Shell's Shellvis)^TM40 and 50, and Lubrizol7308 and 7318); styrene/maleate copolymers which are dispersant copolymers (e.g. of Lubrizol)3702 and 3715); polymethacrylates, some of which have dispersant properties (e.g. Viscoplex by RohMax)^TMSeries, Afton's HiteC^TMSeries of viscosity index improvers, and of Lubrizol7702，7727，7725 and7720C) (ii) a Olefin-graft-polymethacrylate polymers (e.g., Viscoplex by RohMax)^TM2-500 and 2-600); and hydrogenated polyisoprene star polymers (e.g., Shell's Shellvis^TM200 and 260).

The VM or DVM may have a weight average molecular weight of 5,000-25,000, or 10,000-20,000, or 12,000-18,000. The number average molecular weight will be proportionally lower, such as 3,000-15,000, or 6,000-12,000. The materials in question generally have a relatively low molecular weight compared to VM and DVM, which may be commonly used in other applications, such as lubricants for internal combustion engines.

In one embodiment, the viscosity index improver can comprise a linear polymer viscosity improver having dispersant functionality, wherein the linear polymer has a weight average molecular weight of 5,000-25,000 or 10,000-20,000, and wherein the linear polymer is present in an amount of from about 0.1 to about 4 weight percent. In one embodiment, the viscosity index improver can comprise a linear polymer as described herein and a polymer having a star structure, for example a star polymer of the (meth) acrylic type, as disclosed in WO2007/127660, Lubrizol, 2007, 11/8.

Viscosity modifiers that may be used are described in U.S. Pat. nos. 5,157,088, 5,256,752, and 5,395,539. Depending on the application, VM and/or DVM may be used in the functional fluid at a concentration of up to 50% or 20% by weight. Concentrations of 0.1 to 20%, or 0.5 to 20%, or 1 to 12%, or 3 to 10%, or 0.1 to 4%, or 1 to 4%, or 20 to 40%, or 20 to 30% by weight of the lubricant composition may be used. Of viscosity improversThe amount is selected within the ability of the skilled person and will be combined with the viscosity of the base oil to provide a kinematic viscosity at 100 ℃ of less than or equal to 4.7mm²S, for example 2.7 to 4.7, or 2.8 to 4.7, or 3.4 to 4.0, or 3.5 to 3.9mm²Lubricant composition in s.

The lubricant compositions of the disclosed technology may further comprise one or moreDispersing agentSuch as a succinimide dispersant, which in some cases may provide additional boron content to the lubricant composition. Succinimide dispersants are sometimes referred to as ashless dispersants because they are provided without metals and therefore do not normally contribute to sulfated ash when added to a lubricant (although borated detergents may contain boron components that contribute to sulfated ash). However, once the ashless dispersants are added to a lubricant comprising metal-containing species, they may of course interact with environmental metals. Ashless dispersants are characterized by a polar group attached to a relatively high molecular weight hydrocarbon chain. Typical ashless dispersants include N-substituted long chain alkenyl succinimides having a variety of chemical structures, generally including the following simplified structures

Where R is¹Each independently an alkyl group, typically a polyisobutylene group having a molecular weight (Mn) of 500-5000 based on the polyisobutylene precursor, R²Is alkylene, usually ethylene (C)₂H₄) A group. Such molecules are typically derived from the reaction of an alkenyl acylating agent with a polyamine. In addition to the simple imide structures shown above, various linkages between the two moieties are possible, including various amides and quaternary ammonium salts. Also, various structures of the polyamine component are known to be possible, including various cyclic structures. Further, in the above structures, the amine moiety is shown as an alkylene polyamine, but other aliphatic and aromatic mono-and polyamines may also be used. Furthermore, R¹A variety of modes of attachment of groups to imide structures are possible, including a variety ofAre connected in a ring shape. The ratio of carbonyl groups of the acylating agent to nitrogen atoms of the amine can be 1:0.5 to 1:3, in other cases 1:1 to 1:2.75 or 1:1.5 to 1: 2.5. Succinimide dispersants are more fully described in U.S. Pat. nos. 4,234,435 and 3,172,892 and EP 0355895.

The dispersant may also be post-treated by reaction with any of a variety of reagents. Among these are urea, thiourea, dimercaptothiadiazoles, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, nitriles, epoxides, boron compounds and phosphorus compounds. References detailing such treatment are listed in U.S. Pat. No. 4,654,403.

In particular, in one embodiment, the succinimide dispersant used in the disclosed technology may optionally be borated, thus containing and supplying boron to the lubricant formulation. Borated dispersants can be prepared by boration using various agents, such as any of the various forms of a boronic acid (including metaboric acid, HBO)₂Orthoboric acid H₃BO₃And tetraboric acid H₂B₄O₇) Boron oxide, diboron trioxide and alkyl borate. In one embodiment, the borating agent is boric acid, which may be used alone or in combination with other borating agents.

Borated dispersants may be prepared by mixing a boron compound and a succinimide dispersant and heating at a suitable temperature, typically 80 ℃ to 250 ℃, 90 ℃ to 230 ℃, or 100 ℃ to 210 ℃ until the desired reaction occurs. Inert liquids may be used to carry out the reaction. The liquid may comprise toluene, xylene, chlorobenzene, dimethylformamide or mixtures thereof. The boron-containing succinimide dispersant may have a boron content of 0.5 to 1.0 wt%, or 0.6 to 0.9, or 0.54 to 0.85, or 0.56 to 0.83 wt%.

The borated succinimide dispersant may also be a product that has been post-treated to contain additional functionality, for example, by heating together:

(i) a succinimide dispersant;

(ii) a borating agent; and

(ii) optionally 2, 5-dimercapto-1, 3, 4-thiadiazole or a hydrocarbyl substituted 2, 5-dimercapto-1, 3, 4-thiadiazole ("DMTD"), or an oligomer thereof;

(iv) optionally a dicarboxylic acid of an aromatic compound selected from the group consisting of 1,3 diacids and 1,4 diacids; and

(v) optionally a phosphorus acid-containing compound, optionally in the form of a phosphoric acid-containing compound,

the heating is sufficient to provide a product of (i), (ii) and optionally (iii), (iv) and/or (v) which is soluble in an oil of lubricating viscosity. In one embodiment, the borated succinimide dispersant is further treated with a dimercaptothiadiazole.

The dispersant component may also comprise a mixture of individual dispersant species, including untreated (non-borated) succinimide dispersants, borated succinimide dispersants, DMTD treated dispersants, and terephthalic acid treated dispersants. Alternatively, some or all of the post-treatment may be applied to some or all of the succinimide dispersant species. In one embodiment, for example, some or all of the succinimide dispersant may be borated and treated with dimercaptothiadiazole and optionally further treated with terephthalic acid. In one embodiment, a borated succinimide dispersant and a mixture of borated and DMTD treated dispersants may be present. In certain embodiments, the dispersant component may comprise 1 to 4 weight percent of a borated succinimide dispersant that is not treated with a dimercaptothiadiazole, and 0.1 to 1.5 weight percent of a borated succinimide dispersant that is treated with a dimercaptothiadiazole.

The components for preparing the post-treated succinimide dispersant may be combined and reacted in any order. In particular, the boration agent may be a pre-treatment process or a post-treatment process. Thus, for example, boric acid (and optionally phosphoric acid) may be reacted with the dispersant substrate in one step, and then the intermediate borated dispersant may be reacted with the mercaptothiadiazole and the dicarboxylic acid of the aromatic compound. Alternatively, the dispersant substrate, the dicarboxylic acid of the aromatic compound and the mercaptothiadiazole may be first reacted and the product then treated with a borating agent (and optionally with phosphoric acid, phosphorous acid). In another variation, the phosphorylated succinimide dispersant may be prepared by reacting phosphoric acid with a hydrocarbyl-substituted succinic anhydride to prepare a mixed anhydride-acid precursor, and then reacting the precursor with a polyamine to form the phosphorus-containing dispersant. Thereafter, the phosphorus-containing dispersant may be reacted with the dicarboxylic acid of the aromatic compound and the mercaptothiadiazole; and reacted with a borating agent.

The components are typically reacted by heating the borating agent and optional other agents with the dispersant matrix for a sufficient time and temperature to ensure solubility of the resulting product, typically 80-200 deg.C, or 90-180 deg.C, or 120-170 deg.C, or 150-170 deg.C. The reaction time is usually at least 0.5 hour, for example 1-24 hours, 2-12 hours, 4-10 hours or 6-8 hours.

In fully formulated lubricants of the present technology, the amount of succinimide dispersant component (or, in particular, boron-containing succinimide dispersant), if present, may be at least 0.1%, or at least 0.3% or 0.5% or 1% or 1.5%, and in certain embodiments, up to 9% or 8% or 6% or 4% or 3% or 2% by weight of the lubricant composition, such as 1.1-5.5 or 1.0-3.5% by weight. The borated succinimide dispersant component may provide boron to the lubricant formulation in an amount of from 0 to 270 ppm by weight, or from 30, 50, 60, 70, or 100ppm to 270, 250, 225, 200, 180, or 140 ppm. In certain embodiments, the succinimide dispersant component may provide from about 10 to about 250 ppm by weight, or from 20 to 200, or from 50 to 150ppm of sulfur to the composition by the presence of a dimercaptothiadiazole moiety present therewith.

The lubricant compositions of the disclosed technology may further comprise one or moreFoam inhibitor. Defoamers used to reduce or prevent the formation of stable foam include silicones, fluorosilicones, or organic polymers such as acrylate polymers, fluoroacrylate polymers, or fluoromethacrylate polymers. Examples of these and additional defoaming compositions are described in "Foam Control Agents" (Noyes Data corporation) of Henry TCorporation, 1976), pages 125-162. They may generally be present in an amount of from 20 to 250 or from 50 to 200ppm (excluding diluent). Various combinations of defoamers may be used: for example, a first defoaming agent derived from a first defoaming composition comprising polydimethylsiloxane dispersed or dissolved in an aromatic oil or cycloalkane solvent, the first defoaming composition having a kinematic viscosity of 10,000-50,000mm at 25 ℃ (in the absence of solvent)²S; a second antifoaming agent comprising polydimethylsiloxane dispersed or dissolved in an aromatic oil or cycloalkane solvent and having a kinematic viscosity at 25 ℃ (solvent-free) of 80,000-²S; and a third antifoaming agent comprising a fluorinated polysiloxane dispersed or dissolved in an aliphatic solvent or a solvent comprising a ketone having 5 to 16 carbon atoms (e.g., an aliphatic ketone) and having a kinematic viscosity at 25 ℃ (in the absence of solvent) of 50 to 500mm²And s. Mixtures of such defoamers are disclosed in U.S. patent 9.3309,480, Loop et al, 2016, 4/12/2016.

Other conventional additives may also optionally be present in amounts conventionally used for automatic transmission lubricants. They include friction modifiers, antioxidants, detergents, corrosion inhibitors, extreme pressure/antiwear agents and seal swell agents.

In the context of an automatic transmission lubricant,friction modifiersAre materials designed to provide a high, stable coefficient of friction for lubricated clutch plates, typically mating plates comprising metallic (iron) and non-metallic compositions such as cellulose surfaces. Friction modifiers are well known to those skilled in the art. A list of friction modifiers that may be used is included in U.S. Pat. nos. 4,792,410, 5,395,539, 5,484,543 and 6,660,695. U.S. Pat. No. 5,110,488 discloses metal salts of fatty acids, particularly zinc salts, useful as friction modifiers. A list of friction modifiers that may be used may include borated alkoxylated fatty amines; a fatty acid amide; a fatty acid metal salt; a fatty epoxide; a sulfurized olefin; a fatty imidazoline; a fatty amine; condensation products of carboxylic acids and polyalkylene polyamines; a glyceride; metal salts of alkyl salicylates; boric acid glyceride; amine salts of alkylphosphoric acids; an alkoxylated fatty amine; an ethoxylated alcohol;an oxazoline; imidazoline; a hydroxyalkyl amide; a tertiary polyhydroxyl amine; and mixtures of two or more thereof.

Non-borated fatty epoxides may also be used as supplemental friction modifiers.

Borated amines that may be used are disclosed in U.S. patent 4,622,158. Borated amine friction modifiers, including borated alkoxylated fatty amines, may be prepared by reacting a boron compound as described above with the corresponding amines, including simple fatty amines and hydroxyl-containing tertiary amines. The amines used to prepare the borated amines may include the commercial alkoxylated fatty amines known under the trademark "ETHOMEEN", available from Akzo Nobel, such as bis [ 2-hydroxyethyl ] -coco amine, polyoxyethylene- [10] coco amine, bis [ 2-hydroxyethyl ] -soya amine, bis [ 2-hydroxyethyl ] -tallow amine, polyoxyethylene- [5] tallow amine, bis [ 2-hydroxyethyl ] oleyl amine, bis [ 2-hydroxyethyl ] octadecanamine and polyoxyethylene [15] octadecylamine. These amines are described in U.S. Pat. No. 4,741,848.

Alkoxylated fatty amines and fatty amines per se (e.g., oleylamines) are useful as friction modifiers. These amines are commercially available.

Both borated and non-borated glycerol fatty acid esters can be used as friction modifiers. Borated glycerol fatty acid esters can be prepared by borating a fatty acid ester of glycerol with a boron source, such as boric acid. The fatty acid esters of glycerol themselves may be prepared by various methods well known in the art. Many of these esters, such as glycerol monooleate and glycerol tallow, are manufactured on a commercial scale. Commercial glycerol monooleate may comprise a mixture of 45% to 55% by weight monoester and 55% to 45% by weight diester.

Fatty acids can be used to prepare the glycerides described above; they can also be used to prepare their metal salts, amides and imidazolines, any of which can also be used as friction modifiers. The fatty acid may contain 6 to 24 carbon atoms, or 8 to 18 carbon atoms. A useful acid may be oleic acid.

Amides of fatty acids may be those prepared by condensation with ammonia or with primary or secondary amines such as diethylamine and diethanolamine. The fatty imidazolines may include cyclic condensation products of acids with diamines or polyamines, such as polyethylene polyamines. In one embodiment, the friction modifier may be a condensation product of a C8-C24 fatty acid and a polyalkylene polyamine, such as the product of isostearic acid and tetraethylenepentamine. The condensation product of a carboxylic acid and a polyalkyleneamine can be an imidazoline or an amide.

The fatty acids may also be present as their metal salts, for example zinc salts. These zinc salts may be acidic, neutral or basic (overbased). These salts can be prepared by the reaction of a zinc-containing reagent with a carboxylic acid or salt thereof. A useful method for preparing these salts is to react zinc oxide with a carboxylic acid. Useful carboxylic acids are those described above. Suitable carboxylic acids include those of the formula RCOOH, wherein R is an aliphatic or alicyclic hydrocarbon group. Especially those wherein R is a fatty group such as stearyl, oleyl, linoleyl or palmityl. Zinc salts are also suitable, wherein the zinc is present in stoichiometric excess over the amount required to make the neutral salt. Salts may be used in which the zinc is present in a stoichiometric amount of 1.1 to 1.8 times, for example 1.3 to 1.6 times the stoichiometric amount of zinc. These zinc carboxylates are known in the art and are described in U.S. patent No. 3367869. The metal salt may also include calcium salts. Examples may include overbased calcium salts.

Sulfurized olefins are also well known commercial materials for use as friction modifiers. Suitable sulfurized olefins are those prepared in accordance with the detailed teachings of U.S. Pat. Nos. 4,957,651 and 4,959,168. Wherein a co-sulfurized mixture of two or more reactants selected from the group consisting of at least one fatty acid ester of a polyhydric alcohol, at least one fatty acid, at least one olefin, and at least one fatty acid ester of a monohydric alcohol is described. The olefin component may be an aliphatic olefin, which typically contains from 4 to 40 carbon atoms. Mixtures of these olefins are commercially available. Vulcanizing agents useful in the process of the present invention include elemental sulfur, hydrogen sulfide, sulfur halides plus sodium sulfide, and mixtures of hydrogen sulfide and sulfur or sulfur dioxide.

Metal salts of alkyl salicylates include calcium and other salts of long chain (e.g., C12-C16) alkyl substituted salicylic acids.

Amine salts of alkyl phosphoric acids include oleyl and other long chain esters of phosphoric acid with amines such as tertiary aliphatic primary amines, under the tradename Primene^TMAnd (5) selling.

85% phosphoric acid is a suitable material for addition to a fully formulated composition to increase friction performance and may be included at a level of 0.01 to 0.3 wt%, for example 0.03 to 0.2 or to 0.1% based on the weight of the composition.

The amount of supplemental friction modifier, if present, may be from 0.01 to 10 or 5 wt.% of the lubricating composition, from 0.1 to 2.5 wt.% of the lubricating composition, for example from 0.1 to 2.0, from 0.2 to 1.75, from 0.3 to 1.5 or from 0.4 to 1%. However, in some embodiments, the amount of friction modifier is present at less than 0.2 wt.%, or less than 0.1 wt.%, for example, 0.01 to 0.1 wt.%.

Antioxidant agentIncluding phenolic antioxidants which may be hindered phenolic antioxidants with one or both ortho positions on the phenolic ring occupied by bulky groups such as t-butyl. The para position may also be occupied by a hydrocarbyl group or a group bridging two aromatic rings. In certain embodiments, the para position is occupied by an ester-containing group, e.g., an antioxidant of the formula

Wherein R is³Is a hydrocarbyl group, such as an alkyl group containing, for example, 1 to 18 or 2 to 12 or 2 to 8 or 2 to 6 carbon atoms; the tertiary alkyl group may be a tertiary butyl group. Such antioxidants are described in more detail in U.S. Pat. No. 6,559,105.

Antioxidants also include aromatic amines. In one embodiment, the aromatic amine antioxidant may comprise an alkylated diphenylamine, such as a nonylated diphenylamine or a mixture of di-nonylated and mono-nonylated diphenylamines.

Antioxidants also include sulfurized olefins, such as mono-or disulfides, or mixtures thereof. These materials typically have sulfide bonds with 1-10, e.g., 1-4, or 1 or 2 sulfur atoms. Materials which can be vulcanized to form the vulcanized organic compositions of the present invention include oils, fatty acids and esters, olefins and polyolefins prepared therefrom, terpenes or Diels-Alder adducts. Details of methods of preparing some such vulcanized materials can be found in U.S. Pat. Nos. 3,471,404 and 4,191,659.

Molybdenum compounds may also be used as antioxidants, and these materials may also be used for various other functions, such as anti-wear agents or friction modifiers. U.S. Pat. No. 4,285,822 discloses lubricating oil compositions containing molybdenum and sulfur compositions prepared by combining a polar solvent, an acidic molybdenum compound, and an oil-soluble basic nitrogen compound to form a molybdenum-containing complex and contacting the complex with carbon disulfide to form a molybdenum and sulfur-containing composition.

Typical amounts of antioxidants will, of course, depend on the particular antioxidant and its respective effectiveness, but illustrative total amounts may be 0.01 to 5% by weight or 0.15 to 4.5% or 0.2 to 4%.

Detergent compositionTypically an overbased material, otherwise known as an overbased or superbased salt, which is typically a homogeneous newtonian system, having a metal content in excess of that present upon stoichiometric neutralization of the metal and the detergent anion. The amount of excess metal is usually expressed as the metal ratio, i.e. the ratio of the total equivalents of metal to the equivalents of acidic organic compound. Overbased materials are prepared by reacting an acidic material (e.g., carbon dioxide) with an acidic organic compound, an inert reaction medium (e.g., mineral oil), a stoichiometric excess of a metal base, and a promoter such as a phenol or alcohol. Acidic organic materials typically have a sufficient number of carbon atoms to provide oil solubility.

Overbased detergents may be characterized by a total base number (TBN, ASTM D2896), the amount of strong acid required to neutralize the basicity of all materials, expressed as mg KOH per gram of sample. Since overbased detergents are typically provided in a form containing a diluent oil, for purposes of this document, the TBN is recalculated to an oil-free basis by dividing by the fraction of detergent that is not oil (as provided). Some useful detergents may have a TBN of 100-800, or 150-750, or 400-700.

The metal compounds that can be used to prepare the basic metal salts are generally any group 1 or group 2 metal compounds (CAS version of the periodic table of the elements). Examples include alkali metals such as sodium, potassium, lithium, copper, magnesium, calcium, barium, zinc and cadmium. In one embodiment, the metal is sodium, magnesium or calcium. The anion portion of the salt may be hydroxide, oxide, carbonate, borate or nitrate.

In one embodiment, the lubricant may comprise an overbased sulfonate detergent. Suitable sulfonic acids include sulfonic and thiosulfonic acids, including mono-or polynuclear aromatic or cycloaliphatic compounds. Certain oil-soluble sulfonates may be prepared from R²T(SO₃ ^-)_aOr R³(SO₃ ^-)_bWherein a and b are each at least 1; t is a cyclic nucleus, such as benzene or toluene; r²Is an aliphatic group such as alkyl, alkenyl, alkoxy or alkoxyalkyl; (R)²) -T typically contains a total of at least 15 carbon atoms; r³Is an aliphatic hydrocarbon group typically containing at least 15 carbon atoms. Group T, R²And R³It may also contain other inorganic or organic substituents. In one embodiment, the sulfonate detergent may be a predominantly linear alkylbenzene sulfonate detergent having a metal ratio of at least 8, as in U.S. patent application 2005065045 [0026 [ ]]-[0037]As described in the paragraph.

Another overbased material is an overbased phenate detergent. The phenol used to prepare the phenate detergent may be prepared from (R)¹)_a-Ar-(OH)_bIs represented by the formula (I) in which R¹Is an aliphatic hydrocarbon group having 4 to 400 or 6 to 80 or 6 to 30 or 8 to 25 or 8 to 15 carbon atoms; ar is an aromatic group such as benzene, toluene or naphthalene; a and b are each at least 1, the sum of a and b amounting to the number of replaceable hydrogens on the aromatic nucleus of Ar, for example 1 to 4 or 1 to 2. Phenate detergents are sometimes also provided as sulfur-bridged species.

In one embodiment, the overbased material is an overbased salicin detergent. Overbased salicin detergents are typically overbased magnesium salts, which are based on salicin derivatives. Salicin detergents are disclosed in more detail in U.S. Pat. No. 6,310,009, with particular reference to their method of synthesis (column 8 and example 1).

Salixarate derivatives and methods for their preparation are described in more detail in U.S. Pat. No. 6,200,936 and PCT publication WO 01/56968. Salixarate derivatives are believed to have predominantly linear rather than macrocyclic structures, although both structures are included in the term "salixarate". Overbased glyoxylate detergents and methods for making the same are disclosed in more detail in U.S. patent 6,310,011 and the references cited therein. The overbased detergent may also be an overbased salicylate, for example an alkali or alkaline earth metal salt of a substituted salicylic acid. Overbased salicylate detergents and methods of making the same are disclosed in U.S. patents 4,719,023 and 3,372,116. Other overbased detergents may include overbased detergents having a mannich base structure as disclosed in U.S. patent 6,569,818.

In certain embodiments, the hydrocarbyl substituent on the hydroxy-substituted aromatic ring (e.g., phenate, salicide, salixarate, glyoxylate, or salicylate) in the above detergents is free or substantially free of C₁₂Aliphatic hydrocarbyl groups (e.g. less than 1%, 0.1% or 0.01% by weight of the substituents being C₁₂An aliphatic hydrocarbon group). In some embodiments, such hydrocarbyl substituents contain at least 14 or at least 18 carbon atoms.

The amount of overbased detergent, if present, in the formulations of the present technology is typically at least 0.6 wt.%, or 0.7 to 5 wt.%, or 1 to 3 wt.%, or 0.05 to 0.55 wt.% on an oil-free basis. A single detergent or multiple detergents may be present. In other words, the amount of overbased calcium detergent may be an amount suitable to provide 110-550 ppm by weight, or 175 or 400 or 175-300 ppm.

Corrosion inhibitorsGenerally referred to as copper (or "yellow metal") corrosion inhibitors. These materials include triazole compounds such as tolyltriazole, tolyltriazoleThe imidazoline compound, the thiadiazole, the carboxylic acid and the salt or ester thereof, and the alkanolamine.

In addition to or in addition to the phosphorus-containing esters detailed above, may also compriseAntiwear agent. Examples include phosphorus-containing antiwear/extreme pressure agents such as phosphate esters and salts thereof, phosphorus-containing carboxylic acids, esters, ethers, and amides; and phosphites. In certain embodiments, the phosphorus antiwear agent may be present in an amount to provide 0.01 to 0.2 or 0.015 to 0.15 or 0.02 to 0.1 or 0.025 to 0.08% phosphorus. Phosphorus-free antiwear agents include borate esters (including borated epoxides), dithiocarbamate compounds, molybdenum-containing compounds, and sulfurized olefins.

Extreme Pressure (EP) agentIncluding some of the materials listed elsewhere herein as well as other sulfur and sulfur chloride containing EP agents, chlorinated hydrocarbon EP agents and phosphorus EP agents. Examples of such EP agents include chlorinated waxes; sulfurized olefins (such as sulfurized isobutylene), organic sulfides and polysulfides such as dibenzyldisulfide, bis- (chlorobenzyl) disulfide, dibutyl tetrasulfide, sulfurized methyl oleate, sulfurized alkylphenols, sulfurized dipentene, sulfurized terpenes, and sulfurized Diels-Alder adducts; phosphosulfurized hydrocarbons, such as the reaction product of phosphorus sulfide with turpentine or methyl oleate; phosphorus-containing esters such as dihydrocarbon and trihydrocarbon phosphites, for example dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite; diamyl phenyl phosphite, tridecyl phosphite, distearyl phosphite and polypropylene-substituted phenol phosphite; metal thiocarbamates such as zinc dioctyldithiocarbamate; amine salts of alkyl and dialkyl phosphoric acids or derivatives, including, for example, the reaction of dialkyl dithiophosphoric acids with propylene oxide, followed by further reaction with P₂O₅Amine salts of the reaction products of the reaction; and mixtures thereof (as described in U.S. patent 3,197,405).

Seal swelling agentIncluding oil-soluble esters and oil-soluble sulfones, sulfolanes, such as isodecylsulfone, benzyl esters, lactones, nitriles, phenolic materials or phthalates.

As used herein, the term "condensation product" is intended to encompass esters, amides, imides, and other such materials that can be prepared by the condensation reaction of an acid or reactive equivalent of an acid (e.g., an acid halide, anhydride, or ester) with an alcohol or amine, whether or not the condensation reaction actually is carried out directly resulting in the product. Thus, for example, a particular ester may be prepared by a transesterification reaction rather than directly by a condensation reaction. The resulting product is still considered to be a condensation product.

Unless otherwise indicated, the amounts of each chemical component recited do not include any solvent or diluent oils that may typically be present in the commercial material, i.e., based on the active chemical. However, unless otherwise indicated, each chemical species or composition referred to herein should be interpreted as a commercial grade material, which may contain isomers, by-products, derivatives, and other such materials that are normally understood to be present in the commercial grade.

As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, as is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the rest of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include:

hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, as well as aromatic, aliphatic, and alicyclic-substituted aromatic substituents, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (e.g., two substituents together form a ring);

substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon nature of the substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfinyl);

hetero-substituents, that is, substituents which, while having a predominantly hydrocarbon character in the context of the present invention, contain elements other than carbon in a ring or chain otherwise composed of carbon atoms, include pyridyl, furyl, thienyl and imidazolyl. Heteroatoms include sulfur, oxygen, and nitrogen. Generally, no more than 2 or no more than 1 non-hydrocarbon substituent per 10 carbon atoms in the hydrocarbyl group; alternatively, non-hydrocarbon substituents may not be present in the hydrocarbyl group.

It is known that some of the above materials may interact in the final formulation such that the components of the final formulation may be different from the components initially added. For example, metal ions (e.g., of a detergent) may migrate to other acidic or anionic sites of other molecules. The products formed thereby, including products formed when using the lubricant compositions of the presently disclosed technology in their intended use, may not be easily described. However, all such modifications and reaction products are intended to be included within the scope of the presently disclosed technology; the disclosed technology includes lubricant compositions prepared by mixing the above components.

Needle roller bearings are roller bearings in which the rollers have a high aspect ratio, for example at least 3:1 or 4:1 and at most, for example 10: 1. The rollers may be used in compression bearings, and the rollers may be oriented radially with respect to the axis of rotation of the bearing. Needle roller bearings may have a higher load capacity than other roller bearings.

The invention may be used to lubricate a transmission such as an automatic transmission; the method comprising adding thereto a lubricant composition as described herein. It is particularly useful wherein the automatic transmission comprises bearings, such as needle bearings, lubricated by the lubricant composition. The advantages and uses of the disclosed technology may be better understood with reference to the following examples.

Examples. The following lubricant formulations were prepared and tested. All amounts reported are on an oil-free basis and are reported in weight percent unless otherwise indicated.

Example 1A mineral oil-based formulation comprising:

0.13% borated epoxide (borate ester with 14-16 carbons) containing 2.1% B (thus contributing 27ppm boron to the lubricant)

3.1% borated succinimide dispersant containing 0.82% B (thus contributing 253ppm boron to the lubricant [ I calculate from 116.31+116.32 ]

0.23% dibutyl phosphite containing 15.5% P (thus contributing 357ppm phosphorus to the lubricant)

0.08% phosphate ester of C18 alcohol, containing 5.25% P (thus contributing 42ppm phosphorus to the lubricant)

0.9% of an acrylic-based viscosity modifier with star structure,

0.16% overbased calcium sulfonate detergent

Plus conventional friction modifiers, antioxidants, corrosion inhibitors and other performance additives for automatic transmission lubricants.

For example 1, this example had the following properties: FINISH BLEND KV100 is 4.27cSt, KV40cSt is 17.7 cSt; BOV 3.15 cSt; 368ppm for B, 322ppm for Ca, 736ppm for P and 1763ppm for S.

Example 2A mineral oil-based formulation comprising:

0.15% borated epoxide (borate ester with 14-16 carbons) containing 2.1% B (thus contributing 32ppm boron to the lubricant)

0.1% borate ester based on an alcohol having 8 carbons, containing 2.7% B (thus contributing 20ppm boron to the lubricant)

3.2% borated succinimide dispersant containing 0.82% B (thus contributing 262ppm boron to the lubricant)

0.2% of an oligomeric phosphite containing 15.4% P (thus contributing 306ppm phosphorus to the lubricant)

0.12% phosphate ester of C18 alcohol, containing 5.25% P (thus contributing 63ppm phosphorus to the lubricant)

0.87% of acrylic-based viscosity improvers having various structures,

0.28% overbased calcium sulfonate detergent

For example 2, this example had the following properties: FINISH BLEND KV100 is 3.84cSt, KV40cSt is 15.7 cSt; BOV 2.98cSt, B328 ppm, Ca 298ppm, P586 ppm, S1617 ppm.

Example 3.A mineral oil-based formulation comprising:

2.8% borated succinimide dispersant containing 0.4% B (thus contributing 128ppm boron to the lubricant)

0.5% of a mixture containing DMTD dispersant

0.23% alkyl phosphite antiwear agent containing 15.5% P (thus contributing 357ppm phosphorus to the lubricant)

0.28% overbased calcium sulfonate detergent

For example 3, this example had the following properties: FINISH BLEND KV100 is 3.82cSt, KV40cSt is 15.5 cSt; BOV 2.98cSt, B344 ppm, Ca 303ppm, P607 ppm, S1755 ppm.

Example 4.A mineral oil-based formulation comprising:

0.15% borate ester based on an alcohol having 8 carbons, containing 2.7% B (thus contributing 41ppm boron to the lubricant)

2.6% non-borated succinimide dispersant

0.7% borated succinimide dispersant containing 0.4% B (thus contributing 127ppm boron to the lubricant)

0.65% of a mixture containing DMTD dispersant

0.12% phosphate ester of C18 alcohol, containing 5.25% P (thus contributing 79ppm phosphorus to the lubricant)

0.25% of an alkyl phosphite antiwear agent containing 15.5% P (thus contributing 388ppm phosphorus to the lubricant)

0.28% overbased calcium sulfonate detergent

For example 4, this example had the following properties: FINISH BLEND KV100 is 3.84cSt, KV40cSt is 15.8 cSt; BOV 2.98cSt, B298 ppm, Ca 301ppm, P570 ppm, S1615 ppm

Example 5 is a commercially available automatic transmission fluid sample for comparison. It is the sample Shell^TMATF134FE, a high performance automatic transmission fluid commercially available from Shell. For example 5, this example had the following properties: FINISH BLEND KV100 ═ 5.3cSt, KV40 ═ 23.8 cSt. Toyota WS in Toyota has a BOV of about KV100 ═ 3.3cst (BOV). 70ppm for B, 130ppm for Ca, 271ppm for P and 729ppm for S.

Example 6 is also a commercially available automatic transmission fluid sample for comparison. It is prepared from Toyota^TMCommercial Toyota WS (world standard) automatic transmission fluids. For example 6, this example had the following properties: finshblend KV100 ═ 4.35cSt and KV40 ═ 18.1 cSt. The BOV of Shell ATF134 is about KV100 ═ 3.0cst (BOV). 136ppm for B, 236ppm for Ca, 343ppm for P and 1669ppm for S.

In Unisteel^TMNeedle bearing testing was performed on bearing sets for the formulations of examples 1-4. 100mL samples of each lubricant were evaluated using a bearing with 12 thrust needles, each sample was run 6 times with an applied load of 10,000N, a speed of 1.1-1.5m/s (corresponding to a 12,250rpm needle speed and a shaft speed of about 700 rpm), and a maximum pressure of 2.6GPa at 120 ℃. Test results are shown as L10 and L50, and Weibull analysis was performed on the fitted data. L10 represents the number of revolutions (determined by dimple formation, usually detected as vibration) with a bearing failure probability of 10%, and L50 represents the number of revolutions with a failure probability of 50%. The results reported in revolutions (cycles) are shown in the following table:

	L10	L50	KV100(cSt)	KV40(cSt)
					example 1	285,000	920,000	4.27	17.7
Example 2	592,000	2,100,000	3.84	15.7
					Example 3	700,000	2,000,000	3.82	15.5
Example 4	163,000	610,000	3.84	15.8
					Example 5	42,000	255,000	5.30	23.8
Example 6	148,000	500,000	4.35	18.1

The formulations of examples 1-4 of the present invention provide good bearing life.

Each of the documents mentioned above is incorporated herein by reference, including any prior applications claiming priority, whether or not specifically listed above. Reference to any document is not an admission that such document qualifies as prior art, or forms the common general knowledge of a skilled person in any jurisdiction. Except in the examples, or where otherwise explicitly indicated, all numbers 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 specific limits described herein may be independently combined. Similarly, the ranges and amounts for each element of the invention can be used with ranges or amounts for any of the other elements.

As used herein, the transitional term "comprising" synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional unrecited elements or method steps. However, in each statement herein that "comprises" the term also includes the phrases "consisting essentially of and" consisting of as alternative embodiments, "wherein" consists of "excludes any elements or steps not specified," consisting essentially of "allows for the inclusion of other unrecited elements or steps that do not materially affect the basic and novel characteristics of the composition or method under consideration. The expression "consisting of or" consisting essentially of, when applied to an element of a claim, is intended to limit all species of the type represented by that element, notwithstanding the presence of "comprising" elsewhere in the claim.

While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. In this respect, the scope of the invention is limited only by the following claims.

Claims

1. A lubricant composition comprising:

(a) kinematic viscosity at 100 ℃ of about 2.2 to about 3.7mm²Oil per second;

(b) at least one borate ester having an alkyl group having from 4 to about 18 carbon atoms in an amount to provide from about 25 to about 300, or from about 30 to about 150, or from 50 to 100, ppm by weight boron to the composition; and

(c) at least one phosphorus-containing ester in an amount to provide from about 150 to about 650 ppm by weight phosphorus to the composition;

wherein the lubricant composition has a kinematic viscosity at 100 ℃ of less than or equal toEqual to about 4.7mm²/s。

2. The lubricant composition of claim 1 wherein:

the amount of the at least one borate ester (b) is from about 0.1 to about 1.1 wt%, or from 0.15 to about 0.7 wt%; and

the at least one phosphorus-containing ester (c) is present in an amount of about 0.05 to about 0.40 weight percent.

3. The lubricant composition of claim 1 or 2 wherein the composition comprises from about 100 to about 500ppm boron and from about 150 to about 1000ppm phosphorus.

4. A lubricant composition as set forth in claim 1 wherein the oil of component (a) comprises an API group II or group III oil or mixtures thereof.

5. The lubricant composition of any of claims 1 through 4 wherein (b) said at least one borate component comprises a borate having an alkyl group having from 4 to 12 carbon atoms and a borate having an alkyl group having from 14 to about 18 carbon atoms.

6. The lubricant composition of any of claims 1 through 4 wherein (b) said at least one borate component comprises a borated epoxide having from about 12 to about 18 carbon atoms.

7. The lubricant composition of any of claims 1 through 5 wherein (b) said at least one borate component comprises the reaction product of boric acid and an alcohol having from about 6 to about 12 carbon atoms.

8. The lubricant composition of any of claims 1 through 6 wherein (C) the phosphorus-containing ester comprises a C4-C6 alkyl phosphite such as dibutyl phosphite or an oligomeric phosphite that is the reaction product of a monomeric phosphorous acid or ester and an alkylene glycol.

9. The lubricant composition of any of claims 1 through 7 further comprising (d) a viscosity index improver.

10. The lubricant composition of claim 8 wherein (d) the viscosity index improver comprises a poly (meth) acrylate containing a nitrogen-containing dispersant monomer.

11. The lubricant composition of claim 8 wherein (d) the viscosity index improver comprises a linear polymer viscosity improver having dispersant functionality, wherein the linear polymer has a weight average molecular weight of 5,000-25,000, and wherein the linear polymer is present in an amount of from about 0.1 to about 4 weight percent.

12. The lubricant composition of any of claims 1 through 10 further comprising (e) a succinimide dispersant.

13. The lubricant composition of claim 10 wherein (e) the succinimide dispersant comprises a borated succinimide dispersant.

14. The lubricant composition of claim 10 or 11 wherein (e) the succinimide dispersant is further treated with dimercaptothiadiazole.

15. The lubricant composition of any of claims 10 through 13 wherein some or all of (e) the succinimide dispersant is borated and treated with dimercaptothiadiazole.

16. The composition of any of claims 12 to 14 wherein the amount of (e) the boron-containing succinimide dispersant is from about 1.0 to about 3.5 wt%.

17. The lubricant composition of any of claims 10 through 15 wherein the (e) boron-containing succinimide dispersant component provides from about 10 to about 250 ppm by weight sulfur to the composition through the presence of dimercaptothiadiazole moieties present therewith.

18. The lubricant composition of any of claims 12 through 16 wherein the boron content of the (e) boron-containing succinimide dispersant is from about 0.6 to about 0.9 wt.%, or from 0.54 to 0.85, or from 0.56 to 0.83 wt.%.

19. The lubricant composition of any of claims 1 through 17 further comprising at least one of a friction modifier, an antioxidant, a detergent, a corrosion inhibitor, an extreme pressure/antiwear agent, an antifoamant, or a seal swell agent.

20. A lubricant composition comprising:

(a) about 50 to about 98 weight percent of an oil having a kinematic viscosity at 100 ℃ of about 2.2 to about 3.7mm²/s；

(b-1) about 0.1 to about 1.0 weight percent of a borate ester containing a C4-C12 alkyl group;

(b-2) from about 0.15 to about 0.40 weight percent of a borate ester comprising a C14 to about C18 alkyl group;

(e-1) from about 1.0 to about 4.0 weight percent of a borated succinimide dispersant that is not treated with a dimercaptothiadiazole; and

(e-2) about 0.1 to about 1.5 weight percent of a borated succinimide dispersant treated with a dimercaptothiadiazole;

wherein components (b-1), (b-2), (e-1) and (e-2) provide boron in an amount of at least 180ppm by weight of the composition; wherein the lubricant composition has a kinematic viscosity at 100 ℃ of less than or equal to about 4.7mm²/s。

21. A method of lubricating an automatic transmission comprising supplying thereto a lubricant composition according to any one of claims 1 to 19.

22. The method of claim 20, wherein the automatic transmission comprises a bearing lubricated by the lubricant composition.