EP2958980A1

EP2958980A1 - Lubricating composition based on aminated compounds

Info

Publication number: EP2958980A1
Application number: EP14707117.9A
Authority: EP
Inventors: Raphaele IOVINE; Carine PIZARD
Original assignee: Total Marketing Services SA
Current assignee: TotalEnergies Marketing Services SA
Priority date: 2013-02-19
Filing date: 2014-02-18
Publication date: 2015-12-30
Also published as: CN105073960A; US20160002559A1; FR3002235A1; WO2014128104A1; KR20150142670A; FR3002235B1; JP2016506996A

Abstract

The invention relates to a lubricating composition comprising at least one base oil and at least one aminated compound. The lubricating composition according to the invention simultaneously exhibits good anti-wear properties, good fuel economy properties, and good anti-oxidant properties.

Description

Lubricating composition based on amino compounds

The present invention is applicable to the field of lubricants. More particularly, the present invention relates to a lubricating composition comprising at least one amino compound. The lubricant composition according to the invention simultaneously has good anti-wear properties, fuel economy and good antioxidant properties.

The present invention also relates to a process using this composition.

The present invention also relates to a method for reducing the fuel consumption of a vehicle employing this lubricating composition.

The present invention also relates to a method for reducing the oxidation of a lubricating composition by adding an amino compound in this composition. The present invention also relates to the use of an amine compound as a friction modifier in a lubricating composition.

The present invention also relates to the use of an amino compound as an antioxidant in a lubricating composition. Lubricating compositions, and more particularly engine lubricating compositions, are known to include various types of additives, making it possible to provide the composition with particular properties.

Among these additives, antioxidants are commonly used. Indeed, in the presence of air and heat, a lubricating composition can react to form acids or other oxygenated compounds. The antioxidant is then added to the lubricant composition to reduce or block the formation or propagation of intermediate compounds, such as radicals or peroxides, thereby reducing or even blocking the oxidation of the composition.

The antioxidant agents commonly used in the field of lubricants are chosen from zinc dithiophosphates, phenolic compounds, aromatic amines, these compounds may be used alone or as a mixture.

However, they may have some disadvantages. Indeed, the major disadvantage of zinc thiophosphates is that they are metal-bearing and include sulfur, which is not desirable in low-rate lubricants. sulfated ash, low phosphorus and low sulfur content, commonly referred to as "low saps" lubricants.

Moreover, the use of phenolic compounds could be limited in the lubricating compositions, because of the potential risks of these compounds on human health, in particular by their toxicity, persistence and bioaccumulation by the body.

As for aromatic amines, their antioxidant effectiveness is recognized for cold use of a lubricating composition, thus reducing their interest in high temperature conditions corresponding to the operating conditions of an engine.

In addition, following the establishment of the Kyoto Protocol, new environmental protection standards require the automotive sector to build vehicles with reduced emissions and reduced fuel consumption. As a result, the engines of these vehicles are subject to increasingly stringent technical constraints: they turn in particular faster, at higher and higher temperatures and must consume less and less fuel.

The nature of automotive lubricants has an influence on pollutant emissions and fuel consumption. Engine lubricants for automobiles called energy saving or "fuel-eco" (in English terminology), have been developed to meet these new needs.

The improvement of the energetic performances of the lubricating compositions can be obtained in particular by mixing in base oils specific additives such as friction modifiers.

Among the friction modifiers, organometallic compounds comprising molybdenum, such as molybdenum dithiocarbamates, are commonly used. In order to obtain good anti-friction properties, a sufficient quantity of molybdenum must be present within the lubricating composition. However, these compounds have the disadvantage of inducing sediment formation when the lubricating composition has too much molybdenum content. The poor solubility of some of these compounds modifies or even deteriorates the properties of the lubricant composition, in particular its viscosity. However, too much or not enough viscous composition hinders the movement of moving parts, the good start of an engine, the protection of an engine when it has reached its operating temperature, and therefore ultimately causes an increase in fuel consumption. In addition, these molybdenum dithiocarbamates contribute to increasing the ash content, reducing their potential for use in a lubricant composition, especially in Europe. Various technical solutions to replace molybdenum compounds have been described.

US 4,505,835 discloses a lubricating composition comprising an amine compound as a friction modifier. However, this amino compound is defined by a specific chemical structure comprising an ammonium function. However, the compounds comprising an ammonium function, when they are added to a lubricating composition, present a potential risk of thickening of the composition, thus possibly altering the lubricating properties of the composition.

Furthermore, no indication is given in this document as to the existence of antioxidant properties of this compound. In addition, this document teaches more particularly the application of the lubricant composition in the field of marine lubricants.

Furthermore, the combination of antioxidants and friction modifiers in a lubricating composition does not necessarily ensure satisfactory anti-oxidant and anti-wear properties, as these compounds can potentially neutralize.

Formulation and fuel economy requirements are growing, so there is still a need to search for new polyfunctional compounds, having both antioxidant and friction modifier properties, which, once formulated in a lubricant composition , do not destabilize it and make it possible simultaneously to obtain oxidation resistance properties and improved fuel economy.

An object of the present invention is to provide a compound, as well as a lubricating composition comprising said compound, overcoming all or in part the aforementioned disadvantages.

Another object of the invention is to provide a lubricant composition whose formulation is easy to implement.

Another object of the invention is to provide a lubricating composition having antioxidant properties during cold and hot use. Another object of the present invention is to provide a lubrication method for saving energy.

The subject of the invention is thus a lubricating composition comprising at least one base oil and at least one amine compound of formula (I)

)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

R 1 represents a hydrogen atom or a linear or branched alkyl group containing from 1 to 30 carbon atoms;

R ₂ represents a linear or branched alkyl group comprising from 2 to 20 carbon atoms;

R ₃ represents a linear or branched alkyl group comprising from 2 to 20 carbon atoms;

• n represents 2, 3, 4, 5 or 6.

It is known from EP1462093A2 to add a compound of formula (I) in an aqueous medium comprising at least one oxidation base and / or at least one direct dye and at least one polycarboxylic acid or one of these salts. The compositions obtained are essentially dyeing compositions and are used to color the hair. However, this document does not mention the use of a compound of formula (I) in a base oil for the formulation of lubricating composition.

US3687852A discloses the use of aspartic acid derivatives (a compound other than the compounds of formula (I)) in a lubricant composition to improve its lubricity properties.

Surprisingly, the Applicant has found that the presence of an amine compound of formula (I) in a lubricant composition makes it possible to confer good antioxidant properties to the composition, as well as good anti-friction properties, and thus good fuel economy properties.

Thus, the present invention makes it possible to formulate lubricating compositions containing no or very few antioxidants chosen from zinc dithiophosphates, phenol compounds and aromatic amines, and which, however, have equivalent or even improved antioxidant properties.

The present invention also makes it possible to formulate lubricating compositions comprising no or very few molybdenum-based friction modifiers and which nevertheless have anti-friction properties and equivalent or even improved fuel economy.

Advantageously, the lubricant compositions according to the invention have improved storage stability and a viscosity that does not vary or very little over time.

In one embodiment, the lubricant composition consists essentially of at least one base oil and at least one amine compound of formula (I)

(I)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

R 1 represents a hydrogen atom or a linear or branched alkyl group comprising from 1 to 30 carbon atoms;

• n represents 2, 3, 4, 5 or 6. The invention also relates to an engine oil comprising a lubricant composition as defined above.

The invention also relates to a transmission oil comprising a lubricating composition as defined above.

The invention also relates to an industrial lubricating oil comprising a lubricating composition as defined above.

By industrial lubricating oil according to the invention is meant any lubricating oil for application in the lubrication of devices, including mechanical, hydraulic or other, used in the industry, such as fats, oils for metalworking, oils for compressor, turbine oils, chain oils, joint oils, insulating oils such as oils for electrical transformers, oils suitable for heat transfer, oils for refrigerating devices or hydraulic fluids.

Thus, the invention also relates to a hydraulic fluid comprising a lubricant composition as defined above.

The invention also relates to the use of a lubricant composition as defined above for the lubrication of a motor of light vehicles or trucks.

In one embodiment, the invention relates to the use of a lubricant composition as defined above for the lubrication of a gasoline or diesel light vehicle engine.

The invention also relates to the use of a lubricant composition as defined above for reducing the fuel consumption of vehicles.

The invention also relates to a method of lubricating a light vehicle or heavy vehicle engine comprising at least one step of contacting the engine with a lubricant composition as defined above.

In one embodiment, the invention relates to a method for lubricating a gasoline or diesel light vehicle engine comprising at least one step of contacting the engine with a lubricant composition as defined above. The invention also relates to a method of reducing energy losses by friction of a mechanical part comprising at least one step of contacting a mechanical part with a lubricant composition as defined above.

The invention also relates to a method for reducing the fuel consumption of a vehicle comprising at least one step of contacting a mechanical part of the vehicle engine with a lubricating composition as defined above.

The invention also relates to the use of an amino compound of formula (I) as an antioxidant in a lubricant composition

(I)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

• n represents 2, 3, 4, 5 or 6.

The invention also relates to the use of an amino compound of formula (I) as a friction modifier in a lubricating composition

(I)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

n represents 2, 3, 4, 5 or 6.

The invention also relates to a method for reducing the oxidation of a lubricating composition comprising the addition of a compound of formula (I) in said lubricating composition

(I)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

n represents 2, 3, 4, 5 or 6. detailed description

Amino compound

The amino compound present in the lubricating composition according to the invention is composed of formula (I)

)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

• n represents 2, 3, 4, 5 or 6.

In a preferred embodiment, M represents a sodium cation.

In one embodiment, R 1 may represent a linear or branched alkyl group comprising from 5 to 20 carbon atoms, preferably from 9 to 15 carbon atoms. In a preferred embodiment, R 1 represents a linear alkyl group comprising from 1 to 30 carbon atoms, preferably from 5 to 20 carbon atoms, advantageously from 9 to 15 carbon atoms.

In a preferred embodiment, R ₂ represents a linear or branched alkyl group comprising from 2 to 5 carbon atoms. In a preferred embodiment, R ₃ represents a linear or branched alkyl group comprising from 2 to 5 carbon atoms.

In one embodiment, n represents 2, 3 or 4.

In a preferred embodiment of the invention, the amine compound may be chosen from compounds of formula (I) in which:

M represents a sodium cation,

R 1 represents a linear alkyl group comprising from 5 to 20 carbon atoms, preferably from 9 to 15 carbon atoms,

R ₂ represents a linear or branched alkyl group comprising from 2 to 5 carbon atoms,

R ₃ represents a linear or branched alkyl group comprising from 2 to 5 carbon atoms, and

• n represents 2, 3 or 4.

In one embodiment of the invention, R 1 represents a hydrocarbon group which is obtained after reduction of lauric acid.

Preferably, lauric acid is obtained by extraction of coconut oil.

Advantageously, the amino compound is a compound of formula (Ia)

As an example of amine compounds according to the invention, mention may be made of the Chimexane HB product marketed by Chimex.

In one embodiment, the content by weight of amine compound of formula (I) ranges from 0.01 to 3%, preferably from 0.5 to 2% relative to the total weight of the composition. In one embodiment, the invention relates to a lubricant composition comprising:

at least one compound of formula (I),

an antioxidant of zinc dithiophosphate type in a content of less than or equal to 0.5%, preferably ranging from 0.01 to 0.5% by weight relative to the weight of the lubricating composition.

In one embodiment, the invention relates to a lubricant composition comprising:

at least one compound of formula (I),

an antioxidant of phenolic compounds type in a content of less than or equal to 2%, preferably ranging from 0.01 to 2% by weight relative to the weight of the lubricating composition. In one embodiment, the invention relates to a lubricant composition comprising:

at least one compound of formula (I),

an aromatic amine antioxidant in a content of less than or equal to 2%, preferably ranging from 0.01 to 2% by weight relative to the weight of the lubricating composition.

In one embodiment, the invention relates to a lubricant composition comprising:

at least one compound of formula (I),

- A molybdenum-based friction modifier in a content of less than or equal to 0.25%, preferably ranging from 0.01 to 0.25% by weight relative to the weight of the lubricant composition.

Another subject of the invention relates to the use of an amine compound of (I) as an antioxidant in a lubricant composition

(I) in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

• n represents 2, 3, 4, 5 or 6.

The set of characteristics and preferences presented for the amino compound of formula (I) present in the lubricant composition also applies to the use of an amine compound of formula (I) as an antioxidant in a lubricating composition.

In a preferred embodiment, the invention relates to the use of an amino compound of formula (Ia) as an antioxidant in a lubricant composition

(the)

Another subject of the invention relates to the use of an amino compound of

(I) as a friction modifier in a lubricating composition

(I) in which M represents a hydronium, sodium, potassium, lithium or ammonium cation;

• n represents 2, 3, 4, 5 or 6.

The set of characteristics and preferences presented for the amino compound of formula (I) present in the lubricant composition also applies to the use of an amine compound of formula (I) as a friction modifier in a lubricant composition.

In a preferred embodiment, the invention relates to the use of an amino compound of formula (Ia) as a friction modifier in a lubricating composition.

(the)

Other compounds of the lubricating composition:

Base oils The lubricating composition according to the present invention comprises at least one base oil which can be chosen from among the base oils of groups I to V as defined in the API classification (American Petroleum Institute) or its European equivalent: the ATIEL classification. (Technical Association of the European Lubricants Industry) or their mixtures. The base oil or base oil mixture may be of natural or synthetic origin. The base oil or the mixture of base oils may represent at least 50%, preferably at least 60%, more preferably at least 70%, even more preferably at least 80%, relative to the total weight of the lubricating composition. The table below describes the base oil groups according to API classification (API Publication No. 1509 Engine Oil Licensing and Certification System appendix E, 14th Edition, December 1996). The percentages are given by weight based on the total weight of the base oil composition.

The oils of groups I to V can be oils of plant, animal or mineral origin. The so-called mineral base oils include any type of bases obtained by atmospheric and vacuum distillation of crude oil, followed by refining operations such as solvent extraction, desalting, solvent dewaxing, hydrotreating, hydrocracking and hydroisomerization, hydrofinishing.

The base oil of the composition according to the invention may also be a synthetic oil, such as certain esters of carboxylic acids and alcohols or polyalphaolefins. The polyalphaolefins used as base oil, and which are distinguished from the heavy polyalphaolefins which may also be present in the compositions according to the invention, may for example be obtained from monomers having 4 to 32 carbon atoms (e.g. octene, decene), and having a viscosity at 100 ° C ranging from 1.5 to 15 cSt (measured according to ASTM D445 international standard.) Synthetic and mineral oil mixtures can also be used.

Advantageously, the lubricant composition according to the invention is formulated to obtain a kinematic viscosity at 100 ° C. (KV100) ranging from 4 to 25 cSt, preferably from 5 to 22 cSt, more preferably from 5 to 13 cSt, measured according to International Standard ASTM D445.

Advantageously, the lubricant composition according to the invention is formulated to have a viscosity index greater than or equal to 140, preferably greater than or equal to 150, more preferably greater than or equal to 160.

Advantageously, the lubricant composition according to the invention is in the form of an anhydrous composition.

From the examples given below and on the basis of his general knowledge, a person skilled in the art knows how to formulate such compositions.

The invention also relates to an oil comprising a lubricant composition according to the invention. In one embodiment, the subject of the invention is an engine oil comprising a lubricant composition according to the invention.

In one embodiment, the invention also relates to a transmission oil comprising a lubricant composition according to the invention.

Advantageously, the invention relates to an engine oil comprising a lubricant composition according to the invention.

In one embodiment, the oil according to the invention can be grade OW-20 and 5W-30 according to the SAEJ300 classification, characterized by a kinematic viscosity at 100 ° C (KV100) ranging from 5.6 to 12.5 cSt measured according to ASTM D445 international standard.

In another embodiment, the oil according to the invention can be characterized by a viscosity index, calculated according to the international standard ASTM D2230, greater than or equal to 130, preferably greater than or equal to 150, more preferably greater than or equal to to 160.

To formulate a motor oil, base oils having a sulfur content of less than 0.3% by weight relative to the weight of the base oil composition, for example Group III mineral oils, may advantageously be used, and synthetic bases free of sulfur, preferably of group IV, or mixtures thereof.

From the examples and on the basis of his general knowledge, the person skilled in the art knows how to formulate such compositions.

Other additives

According to one embodiment, the lubricant composition according to the invention may further comprise at least one additional additive. The additional additive may be chosen from the group formed by the anti-wear additives, the extreme pressure additives, the various antioxidants of the amine compound of formula (I), the different friction modifiers of the amine compound of formula (I), the overbased or non-overbased detergents, viscosity index improvers, pour point improvers, dispersants, defoamers, thickeners and mixtures thereof. The additive (s) may be introduced in isolation and / or included in packages of additives. The addition of the selected additive (s) depends on the use of the lubricating composition. These additives and their use depending on the purpose of the lubricant composition are well known to those skilled in the art.

In one embodiment of the invention, the additive (s) are suitable for use as a motor oil.

In one embodiment, the lubricating composition may further comprise at least one anti-wear additive, at least one extreme pressure additive or their mixture. The anti-wear and extreme pressure additives protect the friction surfaces by forming a protective film adsorbed on these surfaces. There exists a a wide variety of anti-wear additives, but the most used category in lubricating compositions, especially for motor oil, is that of phosphosulfur additives such as metal alkylthiophosphates, in particular zinc alkylthiophosphates, and more specifically zinc dialkyldithiophosphates or ZnDTP. The preferred compounds have the formula Zn ((SP (S) (OR ₄ ) (OR ₅ )) 2, in which R ₄ and R ₅ , which may be identical or different, independently represent an alkyl group, preferably containing from 1 to 18 carbon atoms. The amine phosphates are also anti-wear additives which can be used in the lubricating compositions according to the invention However, the phosphorus provided by these additives acts as a poison for the catalytic systems of automobiles because these additives are ash generators. These effects can be minimized by partially substituting amine phosphates with non-phosphorus additives, such as, for example, polysulfides, especially sulfur-containing olefins.

In one embodiment, in particular for a motor application, the anti-wear and extreme-pressure additives may be present in the motor oil at contents ranging from 0.01 to 6% by weight, preferably from 0.05 to 4%. %, preferably from 0.1% to 2% relative to the total mass of the engine oil. In one embodiment of the invention, the lubricating composition may further comprise at least one additional friction modifier different from the amine compound of formula (I). The additional friction modifying additive may be a compound providing metallic elements or a compound without ash. Among the compounds providing metal elements, mention may be made of transition metal complexes such as Mo, Sb, Sn, Fe, Cu, Zn, the ligands of which may be hydrocarbon compounds containing oxygen, nitrogen, sulfur or phosphorus. The ashless friction modifiers are of organic origin and may be selected from monoesters of fatty acids and polyols, alkoxylated amines, fatty alkoxylated amines, fatty epoxides, borate fatty epoxides; fatty amines or fatty acid glycerol esters. For the purposes of the present invention, the term "fatty" or "fatty (s)" is intended to mean a hydrocarbon group comprising from 10 to 24 carbon atoms.

In one embodiment, the additional friction-modifying additive may be present at levels ranging from 0.01 to 2% by weight, preferentially from 0.1 to 1.5% in the lubricating composition, relative to the total mass of the lubricating composition.

In one embodiment for a motor application, the additional friction modifying additive may be present in the engine oil at contents ranging from 0.01 to 5% by weight, preferably from 0.1 to 2% in oils. motor, relative to the total mass of the engine oil.

In one embodiment, the lubricating composition may further comprise at least one additional antioxidant additive different from the amine compound of formula (I). The antioxidant additives retard the degradation of the lubricating compositions in service, in particular engine oils in service, which degradation may in particular result in the formation of deposits, the presence of sludge, or an increase in the viscosity of the lubricant composition, especially the engine oil. Antioxidant additives act in particular as radical inhibitors or destroyers of hydroperoxides. Additional antioxidants include antioxidants of phenolic or amine type, phosphosulfur antioxidants. Some of these antioxidants, for example phosphosulfides, can be ash generators. Phenolic antioxidants may be ashless, or may be in the form of neutral or basic metal salts.

The additional antioxidant agents may especially be chosen from sterically hindered phenols, sterically hindered phenol esters and sterically hindered phenols comprising a thioether bridge, diphenylamines, diphenylamines substituted with at least one C 1 -C 12 alkyl group, and Dialkyl aryl diamines and combinations thereof. For the purposes of the present invention, sterically hindered phenol means a compound comprising a phenol group in which at least one vicinal carbon of the carbon carrying the alcohol function is substituted by at least one C 1 -C 10 alkyl group, preferably an alkyl group containing C1-C6, preferably a C4 alkyl group, preferably by the ter-butyl group. Amino compounds are another class of additional antioxidants that can be used, optionally in combination with phenolic antioxidants. Typical examples are aromatic amines of the formula R ₆ R ₇₈ N, in which R ₆ represents an optionally substituted aliphatic group or aromatic group, R ₇ represents an optionally substituted aromatic group, R ₈ represents a hydrogen atom, an alkyl group, a aryl group or a group of formula R ₉ S (O) _z R ₁₀ , where R ₉ represents an alkylene group or an alkenylene group, R ₁₀ represents an alkyl group, an alkenyl group or an aryl group and z represents an integer equal to 0 , 1 or 2. Sulfurized alkyl phenols or their alkali and alkaline earth metal salts can also be used as additional antioxidants. Another class of additional antioxidants is copper compounds, for example copper thio- or dithiophosphates, copper and carboxylic acid salts, dithiocarbamates, sulphonates, phenates, copper acetylacetonates. Copper salts I and II, succinic acid or anhydride may also be used.

The lubricant composition according to the invention may contain any type of additional antioxidant additives known to those skilled in the art. Advantageously, the ashless antioxidants are used.

In one embodiment, the lubricant composition according to the invention may comprise from 0.5 to 2% of at least one additional antioxidant additive by weight relative to the total weight of the lubricating composition.

In one embodiment, the lubricating composition according to the invention may further comprise a detergent additive. The detergent additives reduce in particular the formation of deposits on the surface of the metal parts by dissolving the secondary products of oxidation and combustion. The detergents that can be used in the lubricant composition according to the invention are well known to those skilled in the art. The detergents commonly used in the formulation of lubricating compositions may be anionic compounds having a long lipophilic hydrocarbon chain and a hydrophilic head. The associated cation is typically a metal cation of an alkali or alkaline earth metal. The detergents are preferably chosen from alkali metal or alkaline earth metal salts of carboxylic acids, sulphonates, salicylates and naphthenates, as well as the salts of phenates. The alkali and alkaline earth metals are preferably calcium, magnesium, sodium or barium. These metal salts may contain the metal in an approximately stoichiometric amount or in excess (in an amount greater than the stoichiometric amount). In the latter case, these detergents are called overbased detergents. The excess metal, bringing the overbased character to the detergent, is in the form of metal salts insoluble in the oil, for example carbonate, hydroxide, oxalate, acetate, glutamate, preferably carbonate. In one embodiment, the lubricating composition according to the invention may comprise from 2 to 4% by weight of detergent, relative to the total mass of the lubricating composition.

In one embodiment, the lubricating composition may further comprise at least one viscosity index improving polymer. In particular, the polymers improving the viscosity index make it possible to guarantee good cold strength and minimum viscosity at high temperature, in particular to formulate multi-grade motor oils. Among these compounds, mention may be made of polymeric esters, copolymer olefins (OCP), homopolymers or copolymers of styrene, butadiene or isoprene, hydrogenated or otherwise, polymethacrylates (PMA).

In one embodiment, the lubricant composition according to the invention may comprise from 1 to 15% by weight of viscosity index improving polymers, relative to the total weight of the lubricating composition.

In one embodiment for a motor application, the engine oil according to the invention comprises from 0.1 to 10% by weight of polymers improving the viscosity index, with respect to the total mass of the engine oil, preferably from 0.5 to 5%, preferably from 1 to 2%.

In one embodiment, the lubricant composition according to the invention may further comprise at least one pour point depressant additive. The pour point depressant additives notably improve the cold behavior of the lubricating compositions, by slowing down the formation of paraffin crystals. As examples of pour point depressant additives, mention may be made of alkyl polymethacrylates, polyacrylates, polyarylamides, polyalkylphenols, polyalkylnaphthalenes and alkylated polystyrenes.

In one embodiment, the lubricant composition according to the invention may comprise, in addition, at least one dispersing additive, preferably anhydrous.

The dispersant additives may be selected from the groups formed by succinimides or Mannich bases.

In one embodiment, the lubricating composition according to the invention may comprise from 0.2 to 10% by total weight of dispersants, relative to the total mass of the lubricant composition. The subject of the invention is also a lubricating composition comprising:

from 50 to 99.9% by weight of at least one base oil relative to the weight of the lubricating composition,

from 0.01 to 3% by weight of at least one amine compound of formula (I) relative to the weight of the lubricating composition.

All the characteristics and preferences presented above for the base oil and the amino compound of formula (I) also apply to the above lubricant composition.

The subject of the invention is also a lubricant composition consisting essentially of:

50 to 99.9% by weight of at least one base oil relative to the weight of the lubricant composition,

- 0.01 to 3% by weight of at least one amine compound of formula (I) relative to the total weight of the lubricating composition.

The subject of the invention is also a composition, of the additive concentrate type, comprising:

from 5 to 20%, preferably from 10 to 20% by weight of at least one amine compound of formula (I) relative to the weight of the composition,

from 80 to 95% by weight of at least one other additive relative to the total weight of the composition.

The set of characteristics and preferences presented for the amino compound of formula (I) and for the additional additive also applies to the lubricant composition above.

In one embodiment, the invention relates to a composition comprising: from 5 to 20%, preferably from 10 to 20% by weight, of at least one amine compound of formula (I) relative to the weight of the composition, from 80 to 95% by weight of at least one other additive chosen from antiwear additives, extreme pressure additives, friction modifiers different from the amine compound of formula (I), viscosity index improving polymers, pour point improvers, anhydrous dispersants, defoamers, thickeners and mixtures thereof, based on the weight of the composition.

Advantageously, the composition according to the invention as defined above is in the form of a concentrated composition of amino compound of formula (I).

In one embodiment of the invention, to the concentrated composition according to the invention can be added at least one base oil to obtain a lubricant composition according to the invention. Rooms

The lubricant composition according to the invention can lubricate at least one mechanical part or a mechanical member, in particular bearings, gears, universal joints, transmissions, the piston / piston / sleeve system, the camshafts, the clutch , manual or automatic gearboxes, rockers, crankcases etc.

The invention also relates to a method for reducing the energy losses by friction of a mechanical part, said method comprising at least one step of contacting a mechanical part with a lubricant composition according to the invention.

The set of characteristics and preferences presented for the lubricant composition also applies to the method for reducing the energy losses by friction of a mechanical part according to the invention.

The invention also relates to a method for reducing the fuel consumption of a vehicle, the method comprising at least one step of contacting a lubricant composition according to the invention with at least one mechanical part of the engine of the vehicle . In one embodiment, the invention relates to a method for reducing the fuel consumption of a vehicle, in particular a vehicle traveling in an urban environment or a vehicle having a stop and go system. automatic start called "Stop and Start" system. The set of characteristics and preferences presented for the lubricant composition also applies to the process for reducing the fuel consumption of a vehicle according to the invention.

The invention also relates to the use of a lubricant composition according to the invention for reducing the fuel consumption of vehicles. In one embodiment, the invention relates to the use of a lubricating composition for reducing the fuel consumption of cold vehicles, in particular vehicles traveling only in urban areas or vehicles having an arresting system. and automatic start called "Stop and Start" system. The set of characteristics and preferences presented for the lubricant composition also applies to the use to reduce the fuel consumption of vehicles according to the invention.

The vehicles may include a two or four stroke internal combustion engine. The engines may be gasoline engines or diesel engines intended to be powered by gasoline or conventional diesel. For the purposes of the present invention, the term "conventional gasoline" or "conventional diesel" means engines which are powered by a fuel obtained after refining an oil of mineral origin (such as oil for example). The engines may also be gasoline engines or diesel engines modified to be powered by a fuel based on oils derived from renewable materials such as alcohol-based fuels or biodiesel fuel.

The vehicles may be light vehicles such as automobiles and motorcycles. Vehicles can also be heavy trucks, construction machinery, ships.

The invention also relates to the use of a lubricant composition according to the invention for reducing the energy losses by friction of a metal part, preferably in bearings, gears or universal joints. The set of characteristics and preferences presented for the lubricant composition also applies to the use to reduce frictional energy losses of a metal part according to the invention.

The invention also relates to a process for reducing the oxidation of a lubricating composition comprising the addition of a compound of formula (I) in said lubricant composition.

The set of characteristics and preferences presented for the amino compound of formula (I) applies to the process for reducing the oxidation of a lubricating composition according to the invention. The various objects of the present invention and their implementations will be better understood on reading the examples which follow. These examples are given for information only, and are not limiting in nature.

Example 1 Evaluation of the Antioxidant Properties of Lubricating Compositions According to the Invention

It is a question of evaluating the antioxidant properties of lubricating compositions according to the invention, subjected to a high temperature and in the presence of a metal salt as a catalyst, on the basis of the method below:

A control lubricant composition was prepared according to Table I; the percentages given are percentages by mass.

Table I

A composition B (comparative) comprising an aromatic amine antioxidant and a composition C (according to the invention) according to Table II was prepared; the percentages given are percentages by mass.

Table I I

The antioxidant properties were evaluated according to the following method:

Each composition, in an amount of 27 g, was maintained at a temperature of 170 ° C in the presence of a metal catalyst of the formula Ci ₅ H ₂₅ FeO ₆ diluted in chloroform, and under a flow of air having a flow rate of 10 liters per hour.

The duration of the test was 96h.

Different amounts of metal catalyst were used, corresponding:

- at a quantity of iron of 40ppm, - at a quantity of iron of 60ppm,

- an amount of iron of 80ppm.

The oxidation of each composition was evaluated by measuring the kinematic viscosity increase KV at 40 ° C according to the ASTM D445 standard method.

The results are shown in Table III and represent the RKV, ie the ratio (kinematic viscosity before test at 40 ° C / kinematic viscosity after test at 40 ° C.) × 100 Table III

The results show that the presence of an amino compound according to the invention in a lubricating composition makes it possible to very significantly improve the antioxidant properties of the composition.

It should be noted that the antioxidant properties of a lubricating composition according to the invention are equivalent to, or better than those of a lubricating composition comprising a conventional antioxidant aromatic amine type, this all the more with a content in amine compound according to the invention lower than the aromatic amine antioxidant content

It should be noted that the lubricant compositions according to the invention retain good antioxidant properties under severe oxidation conditions (i.e. corresponding to an iron content of 80 ppm).

Example 2 Evaluation of the Coefficient of Friction of Lubricating Compositions According to the Invention

A lubricating composition D (comparative) was prepared according to Table IV; the percentages given are percentages by mass.

Table IV

The coefficient of friction of each composition was evaluated by a Cameron Plint Laboratory Scratch Test using a Cameron-Plint TE-77 alternative tribometer. The test bench consists of a cylinder / plane tribometer immersed in the lubricant composition to be tested. The coefficient of friction is monitored during the test by measuring the tangential force on the normal force. A cylinder (SKF 100C6) of length 10 mm and diameter 7 mm is applied to the steel plane immersed in the lubricant composition to be tested, the temperature of the lubricant composition is fixed at each test. A sinusoidal reciprocating motion is applied with a defined frequency. Each test lasts 100 seconds. Several load levels have been studied; 52N, 131N, 115N, 255N, 257N and 258N.

The values of the coefficient of friction taken at different temperatures, charges and frequencies and for each of compositions A, C and D are shown in Table IV.

Table IV

The results show that an amino compound according to the invention has anti-friction properties. The results also show that a lubricant composition according to the invention (composition C) makes it possible to obtain coefficients of friction equivalent to or even lower than those of a lubricant composition comprising a usual friction modifier (composition D).

Thus, on the basis of the above results, it can be reasonably envisaged that a lubricating composition according to the invention could make it possible to obtain fuel consumption gains at least equivalent to or even greater than those obtained with a lubricant composition comprising a conventional friction modifier, especially for a cold use of a vehicle.

Claims

claims

Lubricating composition comprising at least one base oil and at least one amine compound of formula (I)

in which :

M represents a hydronium, sodium, potassium, lithium or ammonium cation;

• n represents 2, 3, 4, 5 or 6.

Lubricating composition according to Claim 1, in which:

M represents a sodium cation;

R 1 represents a linear or branched alkyl group comprising from 5 to 20 carbon atoms, preferably from 9 to 15 carbon atoms;

R ₂ represents a linear or branched alkyl group comprising from 2 to 5 carbon atoms;

R ₃ represents a linear or branched alkyl group comprising from 2 to 5 carbon atoms;

• n represents 2, 3 or 4.

3. Composition according to claim 1 or 2 wherein R 1 represents a linear alkyl group comprising from 5 to 20 carbon atoms, preferably from 9 to 15 carbon atoms.

4. Lubricating composition according to any one of claims 1 to 3 comprising an amino compound of formula (Ia):

(the)

5. Lubricating composition according to any one of the preceding claims wherein the content by weight of amine compound of formula (I) or (la) ranges from 0.01 to 3%, preferably from 0.5 to 2% relative to to the total weight of the composition.

A lubricating composition according to any one of the preceding claims further comprising at least one additive selected from detergents, anti-wear additives, extreme pressure additives, additional antioxidants, viscosity index improving polymers, point improvers flow, antifoams, thickeners and mixtures thereof.

An engine oil comprising a lubricant composition according to any one of claims 1 to 6.

A transmission oil comprising a lubricating composition according to any one of claims 1 to 6.

Use of a lubricant composition according to any one of claims 1 to 6 for reducing vehicle fuel consumption.

10. A method of reducing energy losses by friction of a mechanical part comprising at least one step of contacting a part mechanical system with a lubricating composition according to any one of claims 1 to 6.

1 1. A method for reducing the fuel consumption of a vehicle comprising at least one step of contacting a mechanical part of the vehicle engine with a lubricant composition according to any one of claims 1 to 6.

12. Use of an amino compound of formula (I) as defined in one of claims 1 to 4 as an antioxidant in a lubricant composition.

13. Use of an amino compound of formula (I) as defined in one of claims 1 to 4 as a friction modifier in a lubricant composition.

14. Process for reducing the oxidation of a lubricating composition comprising the addition of an amine compound of formula (I) as defined in one of claims 1 to 4 in said lubricant composition