GB2449363A

GB2449363A - Lubricating composition

Info

Publication number: GB2449363A
Application number: GB0808983A
Authority: GB
Inventors: David A Hutchison
Original assignee: Afton Chemical Corp
Current assignee: Afton Chemical Corp
Priority date: 2007-05-16
Filing date: 2008-05-16
Publication date: 2008-11-19
Anticipated expiration: 2028-05-16
Also published as: CA2631211A1; JP2008285674A; DE102008022483A1; GB0808983D0; GB2449363B; US20080287328A1; CN101307268A; FR2919302A1

Abstract

A lubricant composition comprises a major amount of a base oil and a minor amount of an additive composition comprising (i) a triazole compound substituted with an aryl moiety; (ii) at least one nitrogen containing compound chosen from an alkylated phenothiazine and a compound represented by the formula (I): ```R<0> - N - (R<1>) (R<2>) (I) wherein R<0>, R<1> and R<2> are each independently selected from an aryl moiety comprising 6 to 30 carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R<0>, R<1> and R<2> are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and (iii) a metal detergent with a soap/TBN ratio ranging from about 0.05 to about 1.5. The composition has a delayed onset of viscosity increase due to oxidation.

Description

LUBRICATING COMPOSITION

DESCRIPTION OF THE DISCLOSURE

Field of the Disclosure

The present disclosure is directed to additive and lubricant compOsitionS and methods for use thereof.

Background of the DiscloSU!

Lubricating oils as used in the internal combustbn engines and transmissions of automobiles or trucks are subjected to a demanding environment during use. This environment results in oxidation of the oil which is catalyzed by the presence of impurities in the oil, and is also promoted by the elevated temperatures of the oil during use.

The oxidation of lubricating oils contributes to the fomiation of sludge in oils and the breakdown of viscosity characteristics of the lubricant. The oxidation is often controlled to some extent by selecting the proper antioxidant additives thereby significantly improving the life of the lubricating oils. Antioxidant additives can extend the useful life of the lubricating oil by, for example, reducing or preventing unacceptable viscosity increases and/or deposit formation.

Additionally, protecting the metal surface of an engine against wear degradation by selecting the proper balance of antiwear agents in a lubricating composition can significantly increase the life of the met& surface. Antiwear agents form a thin film on metal surfaces which prevents metal to metal contact, resulting in a decrease in the amount of wear. A well-known and commonlY used antiwear agent is zinc dialkyldithiOPhoSPhate (ZDDP).

I

However, the demanding environment in which lubricating oils are subjected, including high temperatures and/or high pressures, decompose ZDDP in a lubricating oil composition. Studies have shown that some exhaust emission catalysts may be deactivated by phosphorus, largely derived from ZDDP compounds which have been the mainstay antiwear agents in passenger car motor oil and heavy duty diesel formulaliOfls for the past 50 years. ConsequentlY, future engine oils will contain reduced phosphorus levels. Furthermore, as ZDDP decomposes and releases zinc molecules, these zinc molecules are capable of reacting with other performance addilives present in the lubricating composition, creating sludge and other particulate matter that can cause adverse effects on engine performance. These undesirable effects of oxidation present problems in meeting ever more severe engine performance requirements.

Simply lowering the amount of phosphorus containing compounds, such as ZDDP, is not a practical solution to the problem because of the accompanying reduction of antiwear properties. Therefore, it would be desirable for a lubricating oil composition to comprise reduced phosphorLs containing compound conc2ntratiOnS while also containing improved additives that reduce the oxidative degradation of lubricating oils.

SUMMARY OF THE DISCLOSURE

In accordance with the disclosure, there is provided an additive composition comprising (I) a triazole compound substituted with an aryl moiety; (ii) at least one nitrogen containing compound chosen from an alkylated phenothiaZine and a compound represented by the formula (I): R0 R1R2 (I) *1 wherein R , R1 and R2 are each independentlY selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon atoms, hydrogen, halogen, hydroxy, hydrocarbYl, substituted hydrocarbyl, amino, amido, phosphOrO and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and (iii) a metal detergent with a soapITBN ratio ranging from about 0.05 to about 1.5.

In an aspect, there is also provided a lubricant composition comprising a major amount of a base oil; and a minor amount of an additive composition comprising (i) a triazole compound substituted with an aryl moiety; (ii) at least one nitrogen containing io compound chosen from an alkylated phenothiazifle and a compound represented by the formula (I): R R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon oms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl1 amino, amido, phosphoit, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety compnsing from about 6 to about 30 carbon atoms; and (iii) a metal detergent with a soap/TBN ratio ranging from about 0.05 to about 1.5.

Moreover, there is provided a method of delaying the onset of viscosity increase in a lubricant composition, said method comprising providing to a machine a lubricant composition comprising a major amount of a base oil; and a minor amount of an additive comprising (i) a tnazole compound substituted with an aryl moiety; (ii) at least one nitrogen containing compound chosen from an alkylated phenothiaZifle and a compound represented by the formula (I): R0 R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon oms, hydrogen, halogen, hydroxy hydrocarbYl, substituted hydrocarbYl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and (iii) a metal detergent with a soapITBN ratio ranging from about 0.05 to about 1.5.

Another aspect of the present disdosure is directed to a method of lubricating at least one moving part of a machine. The method comprises contacting the at least one moving part with a lubricant composition comprising a major amount of a base oil and a minor amount of an additive composition. The additive composition comprises a triazole compound substituted with an aryl moiety; at least one nitrogen containing compound chosen from an alkylated phenothiaZifle and a compound represented by the formula (I): R R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon oms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and a metal detergent with a soap/TBN ratio ranging from about 0.05 to about 1.5.

Further, there is provided a method for operating a machine, said method compriSing adding to the machine a lubricant composition comprising a major amount of a base oil: and a minor amount of an additive composition comprising (I) a triazole compound substituted with an aryl moiety; (ii) at least one nitrogen containing compound chosen from an alkylated phenothiaZifle and a compound represented by the formula (I): R0 R1R2 (I) wherein R , R1 and R2 are each independentlY selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon oms, hydrogen, halogen, hydroxy, hydrocarbYl, substituted hydrocarbYl, amino, amido, phosphOrO and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety j5 comprising from about 6 to about 30 carbon atoms; and (iii) a metal detergent with a soapflBN ratio ranging from about 0.05 to about 1.5.

Also provided herein is the use of the additive composition of the invention to delay the onset of viscosity increase in a lubricant composition.

Additional advantages of the disclosure will be set forth in part in the description which follows, and/or can be learned by practice of the disclosure. It is to be understood that both the foregoing general description and the following detailed

-S

description are exemplary and explanatorY only and are not restrictive of the disclosure, as claimed.

DESCRIPTION OF THE EMBODIMENTS

The present disclosure generally relates to an additive composition comprising (i) a triazole compound substituted with an aryl moiety; (ii) at least one nitrogen containing compound chosen from an alkylated phenothiaZifle and a compound represented by the formula (I): R0 R1R2 (I) wherein R , R1 and R2 are each independentlY selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon atoms, hydrogen, halogen, hydroXy, hydrocarbYl, substituted hydrocarbyl, amino, amido, phosphorO, and sulfono, with the proviso that at least one of R , R' and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and a metal detergent with a soapITBN ratio ranging from about 0.05 to about 1.5. The present application is also directed to a lubricant composition comprising a major amount of a base oil and a minor amount of the above described additive composition.

As used herein, the term "major amount" is understood to mean an amount greater than or equal to 50 wt. %, for example from about 80 to about 98 wt.% relative to the total weight of the composition. Moreover, as used herein, the term "minor amount" is understood to mean an amount less than 50 wt. % relative to the total weight of the composition.

As used herein, "aromatic" or uaI.yln unless expressly stated otherwise, refers to substituted or unsubstituted non-aliphatic hydrocarbyl or heterocyclic moieties of this class, e.g., a polyunsaturated typically aromatic, cyclical hydrocarbyl, or heterocyclic substituent, which can have a single ring or multiple rings (up to three rings) that are fused together or linked covalently. Examples of hydrocarbyl aromatic moieties include phenyl, naphthyl, biphenylenyl, phenanthrenyl, phenalenyl, and the like. Such moieties are optionally substituted with one or more substituted or unsubstituted hydrocarbyl substituents. In an aspect, the substituents on the substituted hydrocarbyl substituents can themselves be unsubstituted. In one embodiment, the hydrocarbyl substituents are unsubstituted. Aryl moieties can also be optionally substituted with one or more substituents such as hydroxy, optionally substituted lower alkyl, optionally substituted lower alkoxy, amino, amide, ester moieties and carbonyl moieties (e.g., aldehyde or ketonic moieties). Also included are aryl moieties substituted by other aryl moieties, such as biphenyl. Heterocyclic aryl or aromatic moieties refers to unsaturated cyclical moieties containing carbon atoms in the ring and additionally one or more hetero atoms, such as oxygen, nitrogen, sulfur and/or phosphorus. Examples of suitable heterocyclic aryl or aromatic moieties include pyridyl, thienyl, furyl, thiazolyl, pyranyl, pyrrolyl, pyrazolyl, imidazolyl, pyrazinyl, thiazolyl, etc. Such moieties are optionally substituted with one or more substituents such as hydroxy, optionally substituted lower alkyl, optionally substituted lower alkoxy, amino, amide, ester moieties and carbonyl moieties (e.g., aldehyde or ketonic moieties). In one embodiment, an aryl moiety comprises from about 3 to about 30, for example from about 6 to about 30, carbon atoms.

As used herein, "alkaryl", unless expressly stated otherwise, refers to an alkyl group substituted by any of the substituted or unsubstituted non-aliphatic hydrocarbyl or heterocyclic moieties described above, such as phenyl, naphthyl, benzyl, and the like.

Such moieties are optionally substituted with one or more substituents, such as hydroxy, alkyl, alkoxy, amino, amide, ester and carbonyl moieties (e.g., aldehyde or ketonic moieties).

As used herein, the terms "hydrocarbon", "hydrocarbyl" or "hydrocarbon based" mean that the group being described has predominantly hydrocarbon character within the context of this invention. These include groups that are purely hydrocarbon in nature, that is, they contain only carbon and hydrogen. They may also include groups containing substituents or atoms which do not alter the predominantly hydrocarbon character of the group. Such substituents may include halo-, alkoxy-, nitro-, etc. These groups also may contain hetero atoms. Suitable hetero atoms will be apparent to those skilled in the art and include, for example, sulfur, nitrogen and oxygen. Therefore, while remaining predominantly hydrocarbon in character within the context of this invention, these groups may contain atoms other than carbon present in a chain or ring otherwise composed of carbon atoms.

In an aspect, the terms "hydrocarbon", "hydrocarbyl" or "hydrocarbon based" are used in their ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of a molecule and having a predominantly hydrocarbon character. Examples of hydrocarbyl groups include: (1) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) or aromatic substituents and 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 an alicyclic radical); (2) substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of the description herein, do not alter the predominantly hydrocarbon substituent (e.g., halo (especially chioro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy); (3) hetero-substituentS, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this description, contain other than carbon in a ring or chain otherwise composed of carbon atoms. Hetero-atoms include sulfur, oxygen, nitrogen, and encompass substituents such as pyridyl, furyl, thienyl, and imidazolyl. In general, no more than two, or as a further example, no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non-hydrocarbon substituent in the hydrocarbyl group. In an embodiment, a hydrocarbyl group can comprise from about 1 to about 32 carbon atoms, for example I to about 24 carbon atoms. In another aspect, a hetero-substituent can comprise from I to about 32 carbon atoms, for example I to about 24 carbon atoms, wherein one, two or three of the carbon atoms can be replaced by heteroatoms which are the same or different and can be selected from sulfur, oxygen and nitrogen.

In one embodiment, the substituents on an alkyl, alkenyl, alkoxy, cyclic and hydrocarbyl moiety are unsubstituted.

In an aspect, an alkyl group can be a linear or branched alkyl group containing from 1 to about 32 carbon atoms, for example from I to about 24 carbon atoms. A lower alkyl group typically refers to a said alkyl group which compnses from I to about 12 carbon atoms, for example 1 to about 6 carbon atoms. An alkyl group can be substituted by one or more substituents, for example one, two or three substituentS, which are the same or different and can be selected from halogen, hydroxy, alkoxy, In an aspect, a cycloalkyl group can be a cyclic form of an alkyl group which comprises from 3 to 32 carbon atoms, such as from 3 to 12, for example 5 or 6, carbon atoms. A cycloalkyl group can comprise one or more ring systems.

In an aspect, an alkoxy group can be a group -OR, wherein R is an alkyl group as defined above. An optionally substituted lower alkoxy group can be a group -OR wherein R can be an alkyl group which comprises from 1 to about.12 carbon atoms, for example I to about 6 carbon atoms, and can be unsubstituted or substituted by one or more substituents, for example one, two or three substituents, which are the same or different and can be selected from halogen, hydroxy, alkoxy, amino and thio In an aspect, a halogen can be fluorine, chlorine, bromine or iodine and in one embodiment can be fluorine, chlorine or bromine, such as fluorine or chlorine.

In an aspect, an amino group can be a group -NRR' wherein R and R' are the same or different and represent hydrogen or an alkyl group comprising from I to about 32 carbon atoms, for example from I to about 24 carbon atoms.

In an aspect, a thio group can be a group -SR wherein R represents hydrogen or an alkyl group comprising from 1 to about 32 carbon atoms, for example from I to about 24 carbon atoms.

In an aspect, a sulfono group can be a group -SO2R wherein R represents hydrogen or an alkyl group comprising from I to about 32 carbon atoms, for example from I to about 24 carbon atoms.

In an aspect, an amido group can be a group -C(O)NRR' wherein R and R' are the same or different and represent hydrogen or an alkyl group comprising from I to about 32 carbon atoms, for example from 1 to about 24 carbon atoms.

In an aspect, a phosphoro group can be a group -P(O)RR' wherein R and R' are the same or different and represent hydrogen or an alkyl group comprising from I to about 32 carbon atoms, for example from I to about 24 carbon atoms.

In an aspect, an ester group can be a group -C(O)OR wherein R represents hydrogen or an alkyl group comprising from I to about 32 carbon atoms, for example from I to about 24 carbon atoms.

In an aspect, a carbonyl group can be a group -C(O)R wherein R represents hydrogen or an alkyl group comprising from I to about32 carbon atoms, for example from Ito about 24 carbon atoms.

In an aspect, an alkenyl group can be a linear or branched alkylene group containing from 1 to about 32 carbon atoms, for example from 1 to about 24 carbon atoms. Typically, an alkenyl group or moiety is saturated except for one double bond.

An alkenyl group can be substituted by one or more substituents, for one, two or three substituents, which are the same or different and can be selected from halogen, hydroxy, alkoxy, amino and thio substituents.

In an aspect, a cycloalkenyl group can be a cyclic form of an alkenyl group which comprises from about 3 to about 32 carbon atoms, such as from about 3 to about 12, for example 5 or 6, carbon atoms. A cycloalkenyl group can comprise one or more ring systems.

In an aspect, a cyclic moiety can be a non-aromatic, saturated or unsaturated hydrocarbon ring comprising from about 3 to about 12 carbon atoms in which one or more, for example one, two or three, of the carbon atoms are replaced by a heteroatom selected from N, 0 and S. Typically, the cyclic moiety is unsaturated or has one double bond. The cyclic moiety can comprise one ormore ring systems and can also comprise bridging carbon atoms. When the cyclic moiety comprises one or more ring systems, said systems can be linked by covalent bonds or can be fused. In one embodiment, the cyclic moiety comprises two fused rings. A cyclic moiety can be substituted with one or more substituents, for example one, two or three substituents, which are the same or different and can be selected from hydroxy, alkoxy, amino, amide, ester, oxo, halogen, nitro, thio, phosphoro or sulfono substituents.

A triazole compound suitable for use in the compositions of the present disclosure can be any triazole, including a substituted or unsubstituted triazole compound. In some embodiments the triazole compound is a I,2,3-triazole compound.

In other embodiments the tnazole compound is a I,2,4-triazole compound. In an embodiment, the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole. In another embodiment, the triazole compound is substituted with an aryl moiety. The triazole itself can be further substituted by a substituent such as an alkyl moiety comprising from 1 to about 24 carbon atoms. Thus, in one embodiment, a triazole substituted with an aryl moiety refers to a triazole ring substituted with an aryl group wherein the tnazole ring is further optionally substituted with an alkyl group comprising from I to about 24 carbon atoms. The aryl moiety can be linked to the triazole via a covalent bond, or can be fused to the triazole.

As an example, the triazole compound can be substituted with a substituted or unsubstituted aryl moiety comprising a single ring or multiple rings, for example covalently linked rings. Non-limiting examples of substituted aromatic moieties comprising covalently linked rings include biphenyl, 1,1'-binaphthyl, p,p'-bitolyl, biphenyleflyl, and the like. As another example, the aryl moiety can comprise multiple fused rings. Non-limiting examples of aryl moieties comprising multiple fused rings include naphthyl, anthryl, pyrenyl, phenanthrenyl. phenalenyl, and the like. As a further example, the aryl moiety can comprise a single ring covalently linked to the triazole.

Non-limiting examples of aryl moieties comprising a single ring covalently linked to the triazole include phenyl and the like. As another example, the aryl moiety can comprise a single ring fused to the triazole. Non-limiting examples of aryl moieties comprising a single ring fused to the triazole include benzotriaZOle and tolyltriazOle. An example of a commercially available triazole compound suitable for use herein is a tolyltriazole, which is a light brown powder having a melting point ranging from 80-83 C, a flashpoint of 182 C, and a boiling point of 160 C.

In an embodiment, the triazole compound can be represented by formula (II) below: (lyR4 (I!) wherein R3 is selected from the group consisting of hydrogen and an alkyl moiety comprising from about 1 to about 24 carbon atoms, and wherein R4 is selected from the group consisting of hydrogen, an alkyl moiety comprising from about I to about 24 carbon atoms, and a substituted hydrocarbyl moiety. In another embodiment, R3 and R4 of the triazole compound represented by formula (II) can each independently comprise from about I to about 16 carbon atoms. In one embodiment, when R4 is an alkyl moiety it is an unsubstituted alkyl moiety.

The triazole compound can be present in the disclosed lubricant and additive compositions in any effective amount, which can be readily determined by one of ordinary skill in the art. In an embodiment, the lubricating composition of the present disclosure can comprise from about 0.05 wt.% to about 0.5 wt.%, and for example from about 0.1 wt.% to about 0.3 wt.% of the triazole compound, relative to the total weight of the composition. In another embodiment, the additive composition of the present disclosure can comprise from about 0.48 wt.% to about 5 wt.% of the triazole compound, relative to the total weight of the additive composition.

The disclosed compositions can also comprise at least one nitrogen containing compound. The nitrogen containing compound can be chosen from compounds represented by the formula (I), as described below, and alkylated phenothiazine compounds.

In one aspect of the present application, the nitrogen-containing compound is chosen to be a compound of formula (I): R R1R2 (I) wherein R , R' and R2 are each independently selected from the group consisting of an ar4 moiety comprising from about 6 to about 30 carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms. For example, R , R1 and R2 can each independently be chosen from a substituted or unsubstituted aryl group comprising from about 6 to about 30 carbon atoms. Non-limiting examples of suitable aryl groups include phenyl, benzyl, and naphthyl. Non-limiting examples of suitable substituents for the aryl groups include alkyl, hydrox4, carboxyl, amine and nitro moieties. Examples of alkyl substituted aryl groups include benzyl, phenyl, and naphthyl groups substituted with one or more alkyl groups, wherein the alkyl groups comprise from about 4 to about 30 carbon atoms, such as from about 4 to about 12 carbon atoms. As another example, R , R1 and R2 can each independently be chosen from alkyl substituted benzyl, phenyl, and naphthyl groups. In another example, at least one of R , R1 and R2 is hydrogen.

Non-limiting examples of nitrogen-containing compounds of Formula (I) that are suitable include: phenylamine; diphenylamine; triphenylamifle various alkylated phenylamines, diphenylamines and triphenylamines; N,N'-bis(4-amiflOpheflYl) alkylamine; 3-hydroxydiphenylamifle N-phenyl-1,2-phenylenediamifle N-phenyl-1,4-phenylenediamine; dibutyldiphenylamifle dioctyldiphenylamine dinonyldiphenYlamifle phenyl.alpha-naphthylamifle phenylbeta-naphthylamifle diheptyldipheflylamine and p-oriented styrenated diphenylamifle. Additional non-limiting examples of suitable nitrogen-containing compounds and their methods of preparation include those described in U.S. Patent No. 6,218,576, which descriptions are incorporated herein by reference. In one embodiment, the nitrogen containing compound is an alkylated diphenylamifle.

In some aspects of the present application, the nitrogen-containing compound can comprise multiple nitrogen groups, provided that at least one nitrogen has at least one aryl group attached thero, e.g., as in the case of various diamines having a secondary nitrogen atom as well as an aryl attached to one of the nitrogens. Examples of such diamines include N-Phenyl Phenylene Diamine adducts.

In one aspect of the present application, the nitrogen containing compound is chosen to be an alkylated phenothiazine. Examples of suitable alkylated phenothiazines can include monotetradecylphenothiaZifle, ditetradecyipheflOthiaZifle, monodecyiphenothiazifle, didecyiphenothiazifle, monononyiphenothiazine, dinonyiphenothiaZifle, monoctyiphenothiazine, dioctylphenothiaZine, monobutylphenothiazifle, dibutytphenothiaZifle, monostyryiphenothiazifle, distyrylphenothizifle, butyloctylphenothiaZifle, styryloctyiphenothiazine. Other suitable examples of known alkylated phenothiazine compounds are disclosed in U.S. Patent No. 6,599,865 issued July 29, 2003 to Carl K. Esche, Jr. et al.; U.S. Patent No. 5,614,124, issued March 25, 1997 to Carl K. Esche, Jr. et al.; and U.S. Patent No. 6,797,677 issued September 28,2004 to Carl K. Esche, Jr. et al., the disclosures of which are incorporated herein by reference in their entirety.

The nitrogen-containing compounds used herein can have antioxidant properties in the disclosed compositions when used alone or in combination as described herein.

The nitrogen-containing compounds used herein should be soluble in a final lubricant composition.

The amount of the nitrogen-containing compound in the additive and lubricant compositions can vary depending upon specific requirements and applications. In an embodiment, the lubricating composition of the present disclosure can compnse from about 0.2 wt.% to about 1.2 wt.%, and for example from about 0.4 wt.% to about 1.0 wt.%, of the nitrogen-containing compound, relative to the total weight of the lubricating composition. In another embodiment, the additive compositions of the present disclosure can comprise from about 2 wt.% to about 12 wt.% of the nitrogen-containing compound, relative to the total weight of the additive composition.

The additive and lubricant compositions of the present application can comprise a metal containing detergent, referred to herein as "metal detergent," with a soapITBN ratio ranging from about 0.05 to about 1.5, such as from about 0.1 to about 1.4, or from about 0.15 to about 1. The metal detergent can indude one or more compounds chosen from sulfonates, sulfurized phenates and salicylates. The metal detergent can be a neutral "soap" compound, such as a neutral sulfonate, neutral sulfurized phenate or neutral salicylate; or the detergent can be overbased sulfonate, overbased sulfurized phenate or overbased salicylate; or a combination of both neutral and overbased compounds, such as one or more neutral sulfonates, neutral sulfurized phenates or neutral salicylates in combination with one or more overbased sulfonates, overbased sulfurized phenates or overbased salicylates. Suitable neutral and overbased sulfonates, sulfunzed phenates and salicylates are well known in the art, and any suitable sulfonates, sulfurized phenates and salicylates can be employed in the

compositions of the present disclosure.

The phrase usoapflBN ratio" is defined herein as the ratio of moles of soap compounds to the total base number ("TBN") of the metal detergents employed in the additive or lubricant composition. Thus, the higher thesoap content in the metal detergent, the higher the soapITBN ratio of the metal detergent.

The term "soap" for purposes of this disclosure means a neutral detergent compound that contains approximately the stoichiometric amount of metal to achieve the neutralization of the acidic group or groups present in the acid used to make the detergent. For example, the term "neutral sulfonates," as used herein, means metal salts of sulfonic acids, which salts contain approximately the stoichiometric amount of metal to achieve the neutralization of the acidic group or groups present in the acid.

"TBN" is the amount of potassium hydroxide, in milligrams, that is equivalent to the unneutralized base found in the overbased detergent per gram of metal detergent.

The term "neutral" is used to distinguish from "overbased" detergent, which is a salt that contains significantly more than the stoichiometnc amount of metal that would result in neutralization of the acid. Overbased detergents are well known in the art and any suitable overbased detergents can be employed. Examples of suitable overbased detergents include overbased sulfonates, such the calcium carbonate overbased calcium polyisobutenyl sulfonates and magnesium carbonate overbased magnesium polyisobutenyl sulfonates. Such overbased sulfonates are disclosed, for example, in U.S. Patent 4,137,184, issued to N. Bakker on January 30, 1979, the disdosure of which is hereby incorporated by reference in its entirety. Overbased salicylates and sulfurized phenates are also well known in the art. Examples of well known overbased salicylates and sulfurized phenates are described in U.S. Patent No. 5,919,276. issued to Gareth Charles Jeffrey on July 6, 1999, the disclosure of which is herein incorporated by reference in its entirety.

Detergents can be overbased to various TBN levels. Thus, the soapfTBN ratio can vary based upon the degree of overbasing. In some aspects, lubricant compositions that have soapITBN ratios within relatively low ranges can be useful in the compositions of the present application. However, metal detergents that include higher amounts of soap, such as neutral sulfonate, in addition to the small amount of soap that may already be included in overbased detergents, are believed to provide additional benefits over the overbased detergents alone. For example, in the compositions of the present application, employing detergents having soap/TBN ratios of 0.1 or greater, such as 0.15 or greater, may provide improved antioxidant effects, reduction in viscosity increase over time of the lubricants during use, or may allow for less antioxidant compounds, such as the nitrogen containing compounds described above, to be used in the additive and lubricant compositions.

In one aspect of the present disdosure, the metal detergent comprises at least one neutral sulfonate. The neutral sulfonates suitable for use in compositions of the present disdosure can be any neutral sulfonate compound provided that it is soluble in a lubricant composition. In one aspect of the present application, the neutral sulfonates can have the general formula (Ill), R5-SO3M (III) where R5 is a hydrocarbyl group and M is any of the Group I or Group II metals or lead which forms a salt with the sulfonic acid moiety.

The hydrocarbyl group can be any hydrocarbyl that will render the sulfonate compound soluble in a lubricant. Suitable hydrocarbyl groups can be, for example, substantially saturated, aliphatic hydrocarbyl compounds containing from about 20 to 300 carbon atoms, such as from 50 to about 250. The term "substantially saturated," as used herein, means that at least about 95% of the carbon-to-carbon covalent linkages.

are saturated. Examples of suitable R5 groups include polymers derived from olefins, such as polyisobutylene.

Group I metals for the metal component M can include lithium, sodium and potassium; and the Group II metals can include magnesium, calcium, strontium, barium and zinc. In some aspects of the invention, M is chosen from calcium and magnesium.

Examples of suitable neutral sulfonate compounds include, Calcium polyisobutyenyl sulfonate, magnesium polyisobutenyl sulfonate, and sodium polyisobutyenl sulfonate, Examples of commercially available sulfonate compounds include HiTEC H614 and HITEC 615, both available from Afton Chemical Corporation.

The neutral sulfonate, neutral sulfunzed phenate and neutral salicylate compounds can be present in the disclosed lubricant and additive compositions in any effective amount, which can be readily determined by one of ordinary skill in the art. In one example, the lubricating composition of the present disclosure can comprise from about 0.5 wt.% to about 2 wt.%, such as from about 0.8 wt.% to about 1.8 wt.% of the neutral sulfonate, neutral sulfurized phenate and/or neutral salicylate compounds, relative to the total weight of the composition. In another example, the additive composition of the present disclosure can comprise from about 5 wt.% to about 20 wt.% of the neutral sulfonate, neutral sulfurized phenate and/or neutral salicylate compounds, relative to the total weight of the additive composition.

Determining the total amount of metal detergents, including both neutral and overbased metal detergents, is well within the ordinary skill of the art. Examples of suitable ranges for metal detergents in a lubricant composition can range from about 0.1 to about 15 wt. % based on the total weight of the composition, such as, for example, about 0.2 to about 8 wt. %.

The additive and lubricant compositions disclosed herein can optionally contain additives, such as anti-wear agents, dispersants, ashless-detergentS, pour point depressing agents, viscosity index modifiers, ash-containing friction modifiers, ashless friction modifiers, nitrogen-containing friction modifiers, nitrogen-free friction modifiers, esterified friction modifiers, extreme pressure agents, rust inhibitors, supplemental antioxidants in addition to those described above, corrosion inhibitors, anti-foam agents, titanium compounds, titanium complexes, organic soluble molybdenum compounds, organic soluble molybdenum complexes, boron-containing compounds, boron-containing complexes, and combinations thereof. In an aspect, the anti-wear agents can be oil soluble phosphorus-containing compounds, such as, for example zinc dialkyldithiophosphate salts (ZDDP), which may be present in the additive and lubricant composition in an amount sufficient to provide from about 100 to about 1000 parts per million by weight of total phosphorus in a lubricant composition. In another aspect, the phosphorus-containing compounds may be present in an amount sufficient to provide from about 600 to about 800 parts per million by weight of total phosphorus in a lubricant composition. In yet another aspect, the compositions can comprise various levels of at least one titanium-containing compound depending on the needs and requirements of the application.

Base oils suitable for use in formulating the disclosed compositions can be selected from any of the synthetic or mineral oils or mixtures thereof. Mineral oils include animal oils and vegetable oils (e.g., castor oil, lard oil) as well as other mineral lubricating oils such as liquid petroleum oils and solvent treated or acid-treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic-naphtheniC types. Oils derived from coal or shale are also suitable. Further, oils derived from a gas-to-liquid process are also suitable.

The base oil can be present in a major amount, wherein umajor amount" is understood to mean greater than or equal to 50%, for example from about 80 to about 98 percent by weight of the lubricant composition.

The base oil typically has a viscosity of, for example, from about 2 to about 150 cSt and, as a further example, from about 5 to about 15 cSt at 100 C. Thus, the base oils can normally have a viscosity in the range of about SAE 15 to about SAE 250, and more usually can range from about SAE 20W to about SAE 50. Suitable automotive oils also include cross-grades such as 15W-40, 20W-50, 75W-140, BOW-90, 85W-140, 85W-90, and the like.

Non-limiting examples of synthetic oils include hydrocarbon oils such as polymenzed and interpolymenzed olefin s (e.g., polybutylenes, polypropylefles, propylene isobutylene copolymers, etc.); polyalphaolefins such as poly(1-hexenes), poly-( 1 -octenes), poly( 1 -decenes), etc. and mixtures thereof; alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes, di-nonytbenzenes, di-(2-ethyl hexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, terphenyl, alkylated polyphenyls, etc.); alkylated diphenyl ethers and alkylated diphenyl sulfides and the derivatives, analogs and homologs thereof and the like.

Alkylene oxide polymers and interpolymers and derivatives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc., constitute another class of known synthetic oils that can be used. Such oils are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylefle polymers (e.g., methyl-polyisopropylene glycol ether having an average molecular weight of about 1000, diphenyl ether of polyethylene glycol having a molecular weight of about 500-1000, diethyl ether of polypropylene glycol having a molecular weight of about 1000-1500,.

etc.) or mono-and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C8 fatty acid esters, or the C13 Oxo acid diester of tetraethytene glycol.

Another class of synthetic oils that can be used includes the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acids, alkenyl succiriic acids, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethyihexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycot, etc.) Specific examples of these esters include dibutyl adipate, di(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethyihexyl diester of linoleic acid dimer, the complex ester formed by reacting one mole of sebacic acid with two moles of tetraethylene glycol and two moles of 2-ethylhexanoic acid and the like.

Esters useful as synthetic oils also include those made from C5.12 monocarboxylic acids and polyols and polyol ethers such as neopentyl glycol, trimethylol propane, pentaerythritol, d ipentaerythritol, tripentaerythritol, etc. Hence, the base oil which can be used to make the compositions as described herein can be selected from any of the base oils in Groups I-V as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. Such base oil groups are as follows: Group I contain less than 90% saturates and/or greater than 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120: Group II contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120; Group Ill contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 120; Group IV are polyalphaolefins (PAO); and Group V include all other base oils not included in Group I, II, Ill or IV.

The test methods used in defining the above groups are ASTM D2007 for saturates; ASTM D2270 for viscosity index; and one of ASTM D2622, 4294, 4927 and 3120 for sulfur.

Group IV base oils, i.e. polyalphaolefins (PAO) include hydrogenated oligomers of an alpha-olefin, the most important methods of oligomerisation being free radical processes, Ziegler catalysis, and cationic, Friedel-Crafts catalysis.

The polyalphaolefins typically have viscosities in the range of 2 to 100 cSt at 100 C., for example 4 to 8 cSt at 100 C. They can, for example, be oligomers of branched or straight chain alpha-olefins having from about 2 to about 30 carbon atoms, non-limiting examples include polypropenes, polyisobutenes, poly-I -butenes, poly-1 -hexenes, poly-1-octenes and poly-1-decene. Included are homopolyrnerS, interpolymers and mixtures.

Regarding the balance of the base oil referred to above, a "Group I base oil" also includes a Group I base oil with which base oil(s) from one or more other groups can be admixed, provided that the resulting admixture has characteristics falling within those specified above for Group I base oils.

Exemplary base oils include Group I base oils and mixtures of Group II base oils with Group I bright stock.

Base oils suitable for use herein can be made using a variety of different processes including but not limited to distillation, solvent refining, hydrogen processing, oligomerisation, esterification, and re-refining.

The base oil can be an oil derived from Fischer-TropSCh synthesized hydrocarbons. Fischer-Tropsch synthesized hydrocarbons can be made from synthesis gas containing H2 and CO using a Fischer-TropSCh catalyst. Such hydrocarbons typically require further processing in order to be useful as the base oil. For example, the hydrocarbons can be hydroisomerized using processes disclosed in U.S. Pat. No. 6,103,099 or 6,180,575; hydrocracked and hydroisomeriZed using processes disclosed in U.S. Pat. No. 4,943,672 or 6,096,940; dewaxed using processes disclosed in U.S. Pat. No. 5,882,505; or hydroisomerized and dewaxed using processes disclosed in U.S. Pat. No. 6,013,171; 6,080,301; or 6,165,949.

Unrefined, refined and rerefined oils, either mineral or synthetic (as well as mixtures of two or more of any of these) of the type disclosed hereinabove can be used in the base oils. Unrefined oils are those obtained directly from a mineral or synthetic source without further purification treatment. For example, a shale oil obtained directly from retorting operations, a petroleum oil obtained directly from primary distillation or ester oil obtained directly from an esterification process and used without further treatment would be an unrefined oil. Refined oils are similar to the unrefined oils except they have been further treated in one or more purification steps to improve one or more properties. Many such purification techniques are known to those skilled in the art such as solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, etc. Rerefined oils are obtained by processes similar to those used to obtain refined oils applied to refined oils which have been already used in service. Such rerefined oils are also known as reclaimed or reprocessed oils and often are additionally processed by techniques directed to removal of spent additives, contaminants, and oil breakdown products.

Any concentrations of the various ingredients, including the optional additives and base oils disdosed above, that are effective for providing a desired result can be contained in the compositions of the present application. Non-limiting representative concentrations of ingredients that can be employed in exemplary lubricant compositions of the present application are shown in range I and range 2 of Table 1, below:

TABLE I

Additive Wt. % Wt.% Range I Range 2 Antioxidant system 0-5 0.01-3 Corrosion Inhibitor 0-5 0-2 Metal Dihydrocarby Dithiophosphate 0.1-6 0.1-4 Antifoaming Agent 0-5 0.001-0.15 Friction Modifier 0-5 0-2 Supplemental Antiwear Agents 0-1.0 0-0.8 Pour Point Depressant 0.01-5 0.01-1.5 Viscosity Modifier 0.01-10 0.25-7 Base Oil Balance Balance According to various other aspects of the present application, there is disclosed a method of delaying the onset of viscosity increase in a lubricant composition. As used herein, the term udelaying the onset of viscosity increase" is understood to mean delaying the start of an increase in the viscosity of a lubricant composition over a period of time due to the oxidation process, as compared to a composition that is devoid of the antioxidant compositions of the present application, including a tiiazole compound substituted with an aryl moiety, a nitrogen-containing compound. and a metal detergent compound, as disclosed herein. The method of delaying the onset of viscosity increase in a lubricant composition can comprise providing to a machine a lubricant composition comprising a major amount of a base oil; and a minor amount of an additive comprising (i) a triazole compound substituted with an aryl moiety; (ii) at least one nitrogen-containing compound chosen from an ailcylated phenothiazine and a compound represented by the formula (I): R0 R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of at east one aryl moiety comprising from about 6 to about 30 atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and (iii) a metal detergent with a soapITBN ratio ranging from about 0.05 to about 1.5.

According to various embodiments, there is also disclosed a method of lubricating at least one moving part of a machine. As used herein, "at least one moving part of a machine" is understood to mean at least one part of a machine which is capable of being in motion, including a gear, piston, bearing, rod, spring, camshaft, crankshaft, and the like. The method of lubricating at least one moving part of a machine comprises contacting the at least one moving part with a lubricant composition comprising a major amount of a base oil; and a minor amount of the disclosed additive composition. In other embodiments, there is also disclosed a method for operating a machine comprising adding a lubricant composition comprising a major amount of a base oil and a minor amount of the disdosed additive composition.

The machine in the disclosed methods can be selected from the group consisting of spark ignition and compression-ignition internal combustion engines. Moreover, the at least one moving part can comprise a gear, piston, bearing, rod, spring, camshaft, crankshaft, and the like.

The lubricant composition can be any composition that would be effective in lubricating a machine. In an aspect, the composition is selected from the group consisting of passenger car motor oils, medium speed diesel engine oils, and heavy duty diesel engine oils that comprise the additive compositions of the present

disclosure.

EXAMPLES

The following examples are illustrative of the invention and its advantageous properties. In these examples, as well as elsewhere in this application, all parts and percentages are by weight of the composition, unless otherwise indicated.

A lubricant composition according to the present application was formulated comprising an antioxidant system, including a triazole compound subituted with an aryl moiety, an aryl amine compound, and a metal detergent compound, in a base composition, as shown in Table 2. The triazole compound employed in Example Composition I was a commercially available tolyltriazole (Cobratec IT-I 00, PMC Specialties Group, Cincinnati, Ohio). The aryl amine compound was an alkylated diphenylamine (Hi-TEC 7190, Afton Chemical Corporation, Richmond, VA), and the metal detergent compound included a commercially available sulfonate (HITEC H614, Afton Chemical Corporation, Richmond, VA).

Comparative examples 2 to 4 were formulated without a triazole compound, as shown in Tables 3 to 5, using the same aryl amine and base composition as in Example 1. The amount of neutral sulfonate shown in Tables 2 to 5 is the amount added to the composition, excluding any neutral sulfonate that may have been included in the overbased metal detergents.

TABLE 2-Example Composition I COMPONENT Wt.% Tnazole 0.2 WPD Rating 5.29 Aryl amine 0.4 ViscositY Metal detergents 3*3 Increase 111.2% (SoapITBN ratio = 0.175) 5 Base composition Remainder TABLE 3-Comparative Example Composition 2 COMPONENT Wt.% Tnazole -Aryl amine 0.4 Metal detergents 1.8 LWPD Rating 3.88 (Soap/TBN ratio 0.08) _________ Viscosity Base composition Remainder Increase 2323% TABLE 4-Comparative Example Composition 3 COMPONENT Wt.% Tnazole -Aryl amine 0.8 Metal detergents 1.8 L WPD Rating 3.98 (Soap/TBN ratio = 0.08) _________ Viscosity Base composition Remainder Increase 129% TABLE 5-Comparative Example Composition 4 COMPONENT Wt.% Thazole -L WPD Rating 2.97 Aryl amine 0.4 ViscosIty Metal detergents 33 Increase 148.5% (Soap/TBN = 0.175) 15 Base composition Remainder The base compositions for Example Compositions 1, 2, 3 and 4 included typical lubricant additives, such as a dispersant system, corrosion inhibitor, metal dihydroarbyl dithiophosphate, antifoaming agent, friction modifier, supplemental antiwear agents, pour point depressant, viscosity modifier and base oil. The base composition was formulated with a base oil meeting the GF-4 standards set forth by the International Lubricants Standardization and Approval Committee (ILSAC), which in the instant example, was a SAE Grade 5W-30 type motor oil.

Sequence IlIG engine tests were performed on Example Composition I and Comparative Example Compositions 2, 3 and 4 using a 1996/1997 231 CID (3,800 cc) Series II General Motors V-6 fuel-injected gasoline engine. The used compositions were evaluated to determine degree of piston deposits during high temperature conditions. The degree of piston deposits was measured in terms of a weighted piston deposit (WPD) rating. The WPD rating was determined by inspection of all 6 pistons for deposit and varnish residue. The degree of piston deposit formation was evaluated according to a cleanliness code numbering I through 10, with 10 being considered clean. The "weighted piston deposit" result is an average of cleanliness ratings for all 6 pistons. A higher WPD rating demonstrates lower piston deposit formation and less oxidative degradation that a particular composition suffers in an engine.

The used compositions were also evaluated to determine increases in viscosity at 40 C by well known methods in the art for measuring kinematic viscosity. The composition was sampled and analyzed every 20 hours. The greater the increase in viscosity, the less stable a particular lubricant composition is to oxidation. A lubricant composition that demonstrates a viscosity increase greater than 150% fails this criterion.

The results demonstrated the advantage of using the disclosed composition to delay the onset of viscosity increase in a lubricant composition. As shown by the foregoing example, Example Composition I comprising the disclosed antioxidant system demonstrated a WPD rating of 5.29 and a viscosity increase of 111.2%. In comparison, Example Composition 2 which was devoid of the disclosed composition demonstrated a WPD rating of 3.88 and a viscosity increase of 232.3%. Example Composition 3, which was devoid of the disclosed composition, but included an increased amount of the aryl amine antioxidant as compared to the Example Composition 1, demonstrated a WPD rating of 3.98 and a viscosity increase of 129%.

Example Composition 4, which was also devoid of the disclosed composition, demonstrated a WPD rating of 2.97 and a viscosity increase of 148.5%. Thus, it can be seen that the disclosed composition surprisingly and significantly reduces piston deposits with reduced increase in kinematic viscosity for lubricant compositions, while allowing lower amounts of the aryl amine antioxidant nitrogen containing compounds to be employed. The reduction in aryl amine antioxidant compounds can be seen as an improvement, as these compounds are expensive and increase the cost of the additive and lubricant compositions.

It is intended that the examples are being presented for the purpose of illustration only and are not intended to limit the scope of the invention disclosed herein. As would be understood by one of ordinary skill in the art, the particular ingredients employed and the concentrations of the ingredients can differ from those used in the examples.

It is noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the," include plural referents unless expressly and unequivocally limited to one referent. Thus, for example, reference to "an antioxidant" includes two or more different antioxidants. As used herein, the term "include" and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items.

For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

While particular embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or can be presently unforeseen can arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they can be amended are intended to embrace all such altematives, modifications variations, improvements, and substantial equivalents.

Claims

1. An additive composition comprising: i. a triazole compound substituted with an aryl moiety; ii. at least one nitrogen containing compound chosen from an alkylated phenothiazine and a compound represented by the formula (I): R RIR2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and iii. a metal detergent with a soap/TBN ratio ranging from about 0.05 to about 1.5.

2. The additive composition of claim 1, wherein the triazole compound is substituted with a substituted aryl moiety comprising multiple rings.

3. The additive composition of claim 1, wherein the triazote compound is substituted with a substituted aryl moiety comprising a single ring.

4. The additive composition of claim 1, wherein the triazole compound is represented by the formula (II): (II) wherein R3 is selected from the group consisting of hydrogen and an alkyl moiety comprising from about I to about 24 carbon atoms, and wherein R4 is selected from the group consisting of hydrogen, an alkyl moiety comprising from about I to about 24 carbon atoms, and a substituted hydrocarbyl moiety.

5. The additive composition of any one of claims 1 to 4, wherein the nitrogen containing compound is a compound of Formula I, wherein two of the R , R1 and R2 groups are phenyl groups.

6. The additive composition of any one of claims I to 5, wherein the nitrogen containing compound is an alkylated diphenylamine.

7. The additive composition of any one of claims 1 to 5, wherein the nitrogen containing compound is an alkylated phenothiazine.

8. The additive composition of any one of claims I to 7, wherein the soapITBN ratio ranges from about 0.1 to about 1.4.

9. The additive composition of any one of claims 1 to 8, wherein the soapITBN ratio ranges from about 0.15 to about 1.

10. The additive composition of any one of claims 1 to 9, wherein the detergent comprises at least one neutral sulfonate compound.

11. The additive composition of claim 10, wherein the neutral sulfonate compound is present in an amount ranging from about 5 wt.% to about 20 wt.%, based on the weight of the additive composition.

12. The additive composition of claim 10 or claim 11, wherein the neutral sulfonate compound is a compound of the formula Ill: R5-SO3M (Ill) where R5 is a hydrocarbyl group and M is an element chosen from Group I or Group II metals or lead.

13. The additive composition of claim 12, wherein R5 is a substantially saturated, aliphatic compound containing from about 20 to 300 carbon atoms.

14. The additive composition of claim 12 or claim 13, wherein R5 is polyisobutylene.

15. The additive composition of any one of claims 12 to 14, wherein M is chosen from lithium, sodium, potassium, magnesium, calcium, strontium, barium, and zinc.

16. The additive composition of any one of claims ito 15, wherein the triazole compound is present in an amount ranging from about 0.48 wt.% to about 5 wt.%, based on the weight of the additive composition.

17. The additive composition of any one of claims I to 16, wherein the nitrogen-containing compound is present in an amount ranging from about 2 wt.% to about 12 wt.%, based on the weight of the additive composition.

18. The additive composition of any one of claims I to 17, further comprising at least one additive selected from the group consisting of phosphorus-containing compounds, dispersants, ashless-detergents, pour point depressing agents, viscosity index improving agents, ash-containing friction modifier, ashless friction modifier, nitrogen-containing friction modifier, nitrogen-free friction modifier, esterified friction modifier, extreme pressure agents, rust inhibitors, supplemental antioxidants, corrosion inhibitors, anti-foam agents, titanium compounds, titanium complexes, organic soluble molybdenum compounds, organic soluble molybdenum complexes, boron-containing compounds, and boron-containing complexes.

19. The additive composition of any one of claims Ito 18, further comprising an oil soluble phosphorus compound having a concentration ranging from about 100 to aboutl000ppm.

20. A lubricant composition comprising: a major amount of a base oil; and a minor amount of an additive composition comprising, i. a triazole compound substituted with an ar4 moiety; ii. at least one nitrogen containing compound chosen from an alkylated phenothiazine and a compound represented by the formula (I): R0 R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, arnido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and iii. a metal detergent with a soap/TBN ratio ranging from about 0.05 to about 1.5.

21. A lubricant composition according to claim 20 wherein the additive composition is as defined in any one of claims 1 to 19.

22. The lubricant composition of claim 20 or claim 21, wherein the triazole compound is present in an amount ranging from about 0.05 wt. % to about 0.5 wt.%, based on the weight of the lubricant composition.

23. The lubricant composition of any one of claims 20 to 22, wherein the triazole compound is present in an amount ranging from about 0.1 wt.% to about 0.3 wt.%, based on the weight of the lubricant composition.

24. The lubricant composition of any one of claims 20 to 23, wherein the nitrogen-containing compound is present in an amount ranging from about 0.2 wt.% to about 1.2 wt.%, based on the weight of the lubricant composition.

25. The lubricant composition of any one of claims 20 to 24, wherein the nitrogen-containing compound is present in an amount ranging from about 0.4 wt.% to about 1.0 wt.%, based on the weight of the lubricant composition.

26. The lubricant composition of any one of claims 20 to 25, wherein the metal detergent comprises a neutral sulfonate compound, wherein the neutral sulfonate compound is present in the lubricant composition in an amount ranging from about 0.5 wt.% to about 2.0 wt.%, based on the weight of the lubricant composition.

27. The lubncant composition of any one of claims 20 to 26, further comprising at least one additive selected from the group consisting of phosphorus-containing compounds, dispersants, ashless-detergents, pour point depressing agents, viscosity index improving agents, ash-containing friction modifier, ashless friction modifier, nitrogen-containing friction modifier, nitrogen-free friction modifier, estenfied friction modifier, extreme pressure agents, rust inhitAtors, supplemental antioxidants, corrosion inhibitors, anti-foam agents, titanium compounds, titanium complexes, organic soluble molybdenum compounds, organic soluble molybdenum complexes, boron-containing compounds, and boron-containing complexes.

28. The lubricant composition of any one of claims 20 to 27, wherein the lubricant composition is selected from the group consisting of passenger car motor oil, medium speed diesel engine oil, and heavy duty diesel engine oil.

29. The lubricant composition of any one of claims 20 to 28, further comprising at least one titanium compound.

30. The lubricant composition of any one of claims 20 to 29, further comprising a phosphorus-containing compound in an amount ranging from about 100 to about 1000 ppm of total phosphorus in a lubricant composition.

31. The lubricant composition of any one of claims 20 to 30, further comprising a phosphorus-containing compound in an amount ranging from about 600 to about 800 ppm of total phosphorus in a lubricant composition.

32. A method of delaying the onset of viscosity increase in a lubricant composition, said method comprising: providing to a machine a lubricant composition comprising a major amount of a base oil; and a minor amount of an additive composition comprising i. a triazole compound substituted with an aryl moiety; ii. at least one nitrogen containing compound chosen from an alkylated phenothiazine and a compound represented by the formula (I): R0 R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about 30 carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and iii. a metal detergent with a soapITBN ratio ranging from about 0.05 to about 1.5.

33. The method of claim 32, wherein the machine is selected from the group consisting of spark ignition and compression-ignition internal combustion engines.

34. A method of lubricating at least one moving part of a machine, said method comprising: contacting the at least one moving part with a lubricant composition comprising a major amount of a base oil and a minor amount of an additive composition comprising, i. a triazole compound substituted with an aryl moiety; ii. at least one nitrogen containing compound chosen from an alkylated phenothiazine and a compound represented by the formula (I): R R1R2 (I) wherein R , R' and R2 are each independently selected from the io group consisting of an aryl moiety comprising from about 6 to about carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl, substituted hydrocarbyl, amino, amido, phosphoro, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an ar1 moiety comprising from about 6 to about 30 carbon atoms; and iii. a metal detergent with a soap/TBN ratio ranging from about 0.05 to about 1.5.

35. The method of claim 34, wherein the machine is selected from the group consisting of spark ignition and compression-ignition internal combustion engines.

36. A method of operating a machine comprising: adding to the machine a lubricating composition comprising a major amount of a base oil; and a minor amount of an additive composition comprising i. a tnazole compound substituted with an aryl moiety; ii. at least one nitrogen containing compound chosen from an alkylated phenothiazine and a compound represented by the formula (I): R R1R2 (I) wherein R , R1 and R2 are each independently selected from the group consisting of an aryl moiety comprising from about 6 to about carbon atoms, hydrogen, halogen, hydroxy, hydrocarbyl.

substituted hydrocarbyl, amino, amido, phosphon, and sulfono, with the proviso that at least one of R , R1 and R2 are chosen to be an aryl moiety comprising from about 6 to about 30 carbon atoms; and iii. a metal detergent with a soapITBN ratio ranging from about 0.05 to about 1.5.

37. The method of claim 36, wherein the machine is selected from the group consisting of spark ignition and compression-ignition internal combustion engines.

38. The method of any one of claims 32 to 37 wherein the lubricant composition is as defined in any one of claims 20 to 31.

39. Use of an additive composition according to any one of claims I to 19 to delay the onset of viscosity increase in a lubricant.

40. An additive composition according to claim I and substantially as hereinbefore described.

41. A lubricant composition according to claim 20 and substantially as hereinbefore described

42. A method according to claim 32 and substantially as hereinbefore described.

43. A method according to claim 34 and substantially as hereinbefore described.

44. A method according to claim 36 and substantially as hereinbefore described.

45. Use according to claim 39 and substantially as hereinbefore described.