WATER-BASED LUBRICANT FOR METALWORKING

Abstract

The invention relates to a lubricating composition comprising water and, relative to the total weight of the lubricating composition: - from 1 to 60% by weight of polyalkylene glycol, - from 0.1 to 30% by weight of alkoxylated fatty alcohol(s), - from 0.1 to 30% by weight of an anti-corrosion system comprising at least one acid and at least one base. The present invention also relates to the use of the lubricating composition according to the invention for metalworking.

Description

Title of the invention: AQUEOUS LUBRICANT FOR METALWORKING TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates to an aqueous lubricant intended for use in metalworking, in particular for deforming metal parts, or for forming, cutting, stamping or rolling metal parts, especially aluminum or steel. STATE OF THE ART

[0002] For metalworking, and in particular for forming operations, especially on aluminum, there are products based on formulas comprising a solvent and a grease. The solvent generally serves as a carrier, allowing the grease, useful for lubrication, to be deposited on the surface of the metal; the solvent evaporates during the operation.

[0003] However, these products containing non-aqueous solvents can be toxic and therefore present a potential health risk. The presence of these non-aqueous solvents may also lead to the marketing of labeled products and the need for people using these products to wear protective equipment, including personal protective equipment, when handling the product.

[0004] Furthermore, these non-aqueous solvent-based products can be difficult to clean and therefore require the use of specific and complex cleaning products. There is thus an advantage to providing a lubricating composition, particularly for metalworking, that addresses the drawbacks of the prior art and, in particular, limits the use of solvents, especially toxic or potentially toxic solvents.

[0005] An objective of the present invention is to provide a lubricating composition, in particular a lubricating composition for metalworking, limiting the use of non-aqueous solvent, in particular toxic or potentially toxic solvent.

[0006] Water-based formulations have been proposed to limit the use of organic solvents.

[0007] The aqueous-based formulations currently on the market do not always meet the expectations of stakeholders for the deformation of metal parts, particularly aluminum, from a part quality standpoint, since they are likely to generate staining problems during heat treatment, heat treatment being generally carried out after the deformation of a metal part. tallique, in particular of an aluminum part.

[0008] Tests carried out with products intended mainly for steel may have limitations on aluminium, a softer material requiring the addition of specific additives.

[0009] Document WO 2017 / 114827 describes an aqueous formulation comprising an alkoxylated fatty alcohol and an anti-corrosion agent.

[0010] The present invention proposes a lubricating composition exhibiting improved lubrication properties for the deformation of metal parts, in particular aluminum and steel, a composition generating little or no volatile organic compounds (VOCs) when heated, in particular up to 80°C. Summary of the invention

[0011] The invention relates to a lubricating composition comprising water and: - 1 to 60% by weight of polyalkylene glycol, - from 0.1 to 30% by weight of alkoxylated fatty alcohol(s), - from 0.1 to 30% by weight of an anti-corrosion system comprising at least one acid and at least one base,

[0012] relative to the total weight of the lubricating composition.

[0013] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight of polyalkylene glycol comprising alkylene oxide motifs having from 2 to 8 carbon atoms, - from 0.1 to 20% by weight of ethoxylated and / or propoxylated fatty alcohol(s), - from 0.1 to 30% by weight of an anti-corrosion system comprising at least one monocarboxylic acid and at least one amine,

[0014] in relation to the total weight of the lubricating composition.

[0015] According to one embodiment, the lubricating composition according to the invention is a ready-to-use composition comprising water and: - 1 to 30% by weight of polyalkylene glycol, - 0.1 to 10% by weight of ethoxylated and / or propoxylated fatty alcohol(s), - from 0.1 to 15% by weight of the anti-corrosion system,

[0016] relative to the total weight of the lubricating composition.

[0017] According to one embodiment, the lubricating composition according to the invention is a concentrated composition comprising water and: - 30 to 60% by weight of polyalkylene glycol, - 1 to 15% by weight of ethoxylated and / or propoxylated fatty alcohol(s), - 10 to 30% by weight of the anti-corrosion system,

[0018] relative to the total weight of the lubricating composition.

[0019] Preferably, said at least one base is chosen from among the alkanolamines, preferably from monoethanolamine, diethanolamine, triethanolamine, digly-colamine, mono-isopropanolamine, diisopropanolamine, triisopropanolamine, methyldiethanolamine, 2-amino-2-ethyl-l,3-propanediol, 2-amino-2-methyl-l-propanol and mixtures thereof.

[0020] Preferably, the polyalkylene glycol(s) are chosen from poly(ethylene glycol), poly(propylene glycol), block copolymers comprising ethylene oxide motifs and propylene oxide motifs, and mixtures thereof, preferably from block copolymers comprising ethylene oxide motifs and propylene oxide motifs and mixtures thereof, preferably further from diblock copolymers ethylene oxide-propylene oxide and triblock copolymers propylene oxide-ethylene oxide-propylene oxide and mixtures thereof.

[0021] Preferably, each polyalkylene glycol has a molecular mass ranging from 500 to 10000 g / mol, preferably from 800 to 5000 g / mol, preferably again from 1000 to 3000 g / mol.

[0022] Preferably, each polyalkylene glycol has a viscosity at 40°C ranging from 10 to 1000 mm2 / s, preferably from 15 to 500 mm2 / s, preferably still from 20 to 400 mm2 / s.

[0023] Preferably, the alkoxylated fatty alcohol(s) are chosen from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols, and mixtures thereof.

[0024] Preferably, each alkoxylated fatty alcohol comprises from 1 to 20 alkoxylated motifs and / or a hydrocarbon chain comprising from 6 to 24 carbon atoms.

[0025] According to one embodiment, the lubricating composition according to the invention is a ready-to-use composition comprising water and: - 5 to 30% by weight of PAGs selected from diblock copolymers of ethylene oxide-propylene oxide and triblock copolymers of propylene oxide-ethylene oxide-propylene oxide and their mixtures, the PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 0.1 to 10% by weight of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and their mixture, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - from 0.05 to 10% by weight of monocarboxylic aliphatic acid(s) comprising 4 to 15 carbon atoms, and - from 0.05 to 10% by weight of alkanolamine(s) chosen from monoethanolamine, diethanolamine, triethanolamine, diglycolamine, mono-isopropanolamine, diisopropanolamine, triisopropanolamine, methyldiethanolamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof,

[0026] in relation to the total weight of the lubricating composition.

[0027] According to one embodiment, the lubricating composition according to the invention is a concentrated composition comprising water and: - 30 to 60% by weight of PAGs selected from diblock copolymers of ethylene oxide-propylene oxide and triblock copolymers of propylene oxide-ethylene oxide-propylene oxide and their mixtures, the PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 1 to 10% by weight of alkoxylated fatty alcohols chosen from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and their mixture, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - 5 to 15% by weight of monocarboxylic aliphatic acid(s) comprising 4 to 15 carbon atoms, and - 5 to 15% by weight of alkanolamine(s) chosen from monoethanolamine, diethanolamine, triethanolamine, diglycolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, methyldiethanolamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1,3-propanediol and mixtures thereof,

[0028] in relation to the total weight of the lubricating composition.

[0029] The invention also relates to the use of the lubricating composition according to the invention, as a fluid for metalworking, in particular for metal deformation and / or for metal forming and / or for metal cutting and / or for metal stamping and / or for metal rolling, the metals being preferably chosen from steel and aluminum.

[0030] Preferably, the emissions of total volatile organic compounds at 80°C according to standard NF EN 12619 are less than 200 ppm, preferably less than 150 ppm, preferably even less than 100 ppm, or even less than 50 ppm.

[0031] The invention makes it possible to provide a multi-service lubricating composition since it can be implemented on different types of metallic surfaces, including aluminum surfaces and steel surfaces.

[0032] The invention makes it possible to provide a lubricating composition having a good toxicological profile and a low impact on the environment.

[0033] The lubricating composition according to the invention generates very few volatile organic compounds (VOCs), or even no VOCs at all, when heated.

[0034] The invention makes it possible to provide a lubricating composition that does not generate oil deposits on the ground, which increases operator safety.

[0035] The lubricating composition according to the invention is little or not staining, it generates very little or no staining when used on metal parts, in particular during post-treatments of aluminum.

[0036] The lubricating composition according to the invention can be implemented for the de forming of thin metal parts, for example for shaping heat exchangers. DETAILED DESCRIPTION OF THE INVENTION

[0037] The invention relates to a lubricating composition comprising water and: from 1 to 60% by weight, preferably from 5 to 60% by weight, of polyalkylene glycol (PAG), from 0.1 to 30% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohol(s), from 0.1 to 30% by weight, preferably from 1 to 30% by weight, of an anti-corrosion system comprising at least one acid and at least one base,

[0038] in relation to the total weight of the lubricating composition.

[0039] The lubricating composition according to the invention can be a ready-to-use composition or a concentrated composition, also called a composition to be diluted.

[0040] Indeed, the lubricating composition according to the invention can be diluted with the addition of water before being used as a fluid for metalworking.

[0041] When the composition is ready for use, it can be used directly as a fluid for metalworking, without the need to dilute it.

[0042] When the composition is a ready-to-use composition, it preferably comprises water and: from 1 to 30% by weight, preferably from 5 to 25% by weight, of polyalkylene glycol, from 0.1 to 10% by weight, preferably from 0.5 to 5% by weight, of ethoxylated and / or propoxylated fatty alcohol(s), from 0.1 to 15% by weight, preferably from 0.5 to 10% by weight, of the anti-corrosion system,

[0043] in relation to the total weight of the lubricating composition.

[0044] When the composition is a composition to be diluted (concentrated), it preferably comprises water and: 30 to 60% by weight, preferably 35 to 55% by weight, of polyalkylene glycol, from 1 to 15% by weight, preferably from 1.5 to 10% by weight, of ethoxylated and / or propoxylated fatty alcohol(s), 10 to 30% by weight, preferably 15 to 25% by weight, of the anti-corrosion system,

[0045] relative to the total weight of the lubricating composition. Polyalkylene glycol (PAG)

[0046] The lubricating composition according to the invention comprises at least one PAG. The PAG may be a polymer or a copolymer. When it is a copolymer, it may be a random copolymer or a block copolymer.

[0047] According to one embodiment, the PAG(s) of the lubricating composition according to the invention are chosen from PAGs comprising alkylene oxide motifs having from 2 to 12 carbon atoms, preferably from 2 to 8 carbon atoms, more preferably from 2 to 4 carbon atoms.

[0048] Typically, within the framework of the present invention, if the PAG comprises a hydroxyl-type terminal group (-OH) and an alkyl-type terminal group, then said alkyl-type terminal group comprises from 1 to 5 carbon atoms.

[0049] According to one embodiment, the PAG(s) used in the lubricating composition according to the invention corresponds to formula (I):

[0050] R-(OA)ZOR' (I)

[0051] in which:

[0052] R and R' represent, independently of each other, a hydrogen atom or alkyl group, linear or branched, comprising from 1 to 5 carbon atoms;

[0053] A, all identical or different, represents an alkyl group, linear or branched, comprising from 2 to 8 carbon atoms;

[0054] z represents an integer greater than or equal to 2, preferably an integer greater than or equal to 4.

[0055] According to one embodiment, the PAG(s) of the lubricating composition according to the invention are chosen from poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), block copolymers comprising ethylene oxide motifs and propylene oxide motifs, and mixtures thereof, preferably from block copolymers comprising ethylene oxide motifs and propylene oxide motifs and mixtures thereof, preferably further from diblock copolymers ethylene oxide-propylene oxide, triblock copolymers propylene oxide-ethylene oxide-propylene oxide, triblock copolymers ethylene oxide-propylene oxide-ethylene oxide, and mixtures thereof.

[0056] For the purposes of this invention, "block copolymers comprising ethylene oxide units and propylene oxide units" means copolymers comprising at least one block resulting from the polymerization of ethylene glycol and at least one block resulting from the polymerization of propylene glycol. They may then be referred to as PEG / PPG.

[0057] For the purposes of this invention, "ethylene oxide-propylene oxide diblock copolymers" means copolymers consisting of two blocks, one block resulting from the polymerization of ethylene glycol and one block resulting from the polymerization of Propylene glycol. They can then be called PEG-PPG.

[0058] For the purposes of this invention, "propylene oxide-ethylene oxide-propylene oxide triblock copolymers" are defined as copolymers consisting of three sequenced blocks: one block resulting from the polymerization of propylene glycol, one block resulting from the polymerization of ethylene glycol, and one block resulting from the polymerization of propylene glycol (in that order). They may then be referred to as PPG-PEG-PPG.

[0059] For the purposes of this invention, "triblock copolymers ethylene oxide-propylene oxide-ethylene oxide" are defined as copolymers consisting of three sequenced blocks: one block resulting from the polymerization of ethylene glycol, one block resulting from the polymerization of propylene glycol, and one block resulting from the polymerization of ethylene glycol (in that order). They may then be referred to as PEG-PPG-PEG.

[0060] The PAG(s) implemented in the invention may optionally include alkyl terminal groups, for example selected from linear or branched alkyl groups comprising 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms.

[0061] Preferably, the lubricating composition according to the invention comprises at least one PAG having an alkyl terminal group comprising 1 to 5 carbon atoms.

[0062] According to one embodiment, the PAG(s) used in the lubricating composition according to the invention corresponds to one of the formulas (II) to (V):

[0063] R-(OCH2CH2)x(OCH2CH(CH3))yOR' (II);

[0064] R-(OCH2CH(CH3))y(OCH2CH2)xOR' (III);

[0065] R-(OCH2CH(CH3))y(OCH2CH2)x(OCH2CH(CH3))y OR' (IV);

[0066] R-(OCH2CH2)x(OCH2CH(CH3))y(OCH2CH2)x OR' (V);

[0067] in which:

[0068] R and R' represent, independently of each other, a hydrogen atom or a saturated alkyl group, linear or branched, comprising from 1 to 5 carbon atoms;

[0069] x and x', whether identical or different, represent an integer greater than or equal to 2, preferably greater than or equal to 4,

[0070] y and y', identical or different, represent an integer greater than or equal to 2.

[0071] Preferably, in compounds of formula (II), (III), (IV) or (V) according to the invention, x, x', y and y' are independently of each other, an integer ranging from 2 to 30, preferably from 4 to 25, advantageously from 6 to 20.

[0072] Preferably, in formula (IV), x is an integer from 2 to 30, preferably from 4 to 25, advantageously from 6 to 20, and the sum y+y' goes from 8 to 45, preferably from 12 to 40, preferably again from 20 to 35.

[0073] Preferably, in formula (V), y is an integer from 2 to 30, preferably from 4 to 25, advantageously from 6 to 20, and the sum x+x' goes from 8 to 45, preferably from 12 to 40, preferably again from 20 to 35.

[0074] According to one embodiment, each PAG included in the lubricating composition according to the invention presents a molecular weight ranging from 500 to 10000 g / mol, preferably from 700 to 5000 g / mol, preferably still from 1000 to 3000 g / mol.

[0075] According to one embodiment, each PAG entering into the lubricating composition according to the invention has a viscosity at 40°C ranging from 8 to 1000 mm2 / s, preferably from 10 to 500 mm2 / s, preferably again from 10 to 400 mm2 / s.

[0076] The viscosity at 40°C can be measured according to ASTM D7042.

[0077] According to one embodiment, each PAG entering into the lubricating composition according to the invention has a pour point below 0°C, preferably below -15°C, preferably even below -20°C.

[0078] The pour point can be measured according to ISO 3016.

[0079] According to one embodiment, each PAG entering into the lubricating composition according to the invention has a cloud point ranging from 10 to 120°C, preferably from 20 to 110°C, preferably still from 40 to 100°C.

[0080] The trouble point can be measured according to standard NF EN 1890.

[0081] The PAG(s) represent from 1 to 60% by weight, preferably from 5 to 60% by weight, of the total weight of the lubricating composition (reduced to 100% by weight).

[0082] PAGs are commercially available products. Alkoxylated fatty alcohol(s)

[0083] According to one embodiment, the alkoxylated fatty alcohol(s) (also called polyalkoxylated fatty alcohols) are chosen from ethoxylated fatty alcohols, propoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and their mixture.

[0084] In the context of the present invention, alkoxylated fatty alcohols are different from PAGs.

[0085] Typically, the alkoxylated fatty alcohols of the lubricating composition are in the form of a mixture of fatty alcohols comprising a distribution of compounds that differ in the number of alkoxylated motifs.

[0086] According to one embodiment, each alkoxylated fatty alcohol comprises from 1 to 20 alkoxylated motifs, preferably from 1 to 10 alkoxylated motifs, the alkoxylated motifs being preferably chosen from ethoxylated motifs, propoxylated motifs and their mixture.

[0087] According to a preferred embodiment, the alkoxylated fatty alcohols used in the lubricating composition according to the invention comprise ethoxylated units, optionally in combination with propoxylated units. Indeed, the ethoxylated units will provide good solubility in water.

[0088] According to one embodiment, each alkoxylated fatty alcohol comprises an aliphatic hydrocarbon chain having from 6 to 24 carbon atoms, preferably from 6 to 16 carbon atoms.

[0089] The lubricating composition according to the invention may comprise a mixture of alkoxylated fatty alcohols in which the alkoxylated fatty alcohols differ from each other by the length of the hydrocarbon chain. According to this embodiment, the hydrocarbon chain, preferably of the alkyl type, comprises from 6 to 18 carbon atoms, preferably from 6 to 14 carbon atoms.

[0090] According to a preferred embodiment, the molar mass of the alkoxylated fatty alcohols ranges from 130 to 900 g / mol, preferably from 170 to 500 g / mol, preferably still from 200 to 400 g / mol.

[0091] Alkoxylated fatty alcohols represent from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of the total weight of the lubricating composition (reduced to 100% by weight).

[0092] Alkoxylated fatty alcohols are commercially available products. Anti-corrosion system

[0093] The anti-corrosion system implemented in the lubricating composition according to the present invention comprises at least one acid and at least one base.

[0094] Among the acids, mention may be made of monocarboxylic aliphatic acids, in particular having from 4 to 15 carbon atoms, for example octanoic acid or isononanoic acid, dicarboxylic aliphatic acids having from 4 to 15 carbon atoms, for example decanedioic acid (sebatic acid), undecanedioic acid, dodecanedioic acid, isononanoic acid, and their mixtures.

[0095] Preferably, the acid of the anti-corrosion system implemented in the invention is a saturated acid.

[0096] Preferably, the acid of the anti-corrosion system implemented in the invention consists of carbon, hydrogen and oxygen atoms.

[0097] Preferably, the acids are chosen from among the monoacids. Indeed, diacids can cause staining problems.

[0098] Among the bases, amines, in particular alkanolamines and amino alcohols, potash and sodium hydroxide can be cited. The base(s) may be chosen from potash, sodium hydroxide, and ethanolamines, such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), triethanolamine (TEA), diglycolamine (DGA), isopropanolamines, such as monoisopropanolamine (MIPA), diisopropanolamine (DIPA) and triisopropanolamine (TIPA), ethyleneamines, such as ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA) and tetraethylenepentamine (TEPA), cyclamines, such as cyclohexylamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof.

[0099] According to one embodiment, the base(s) are chosen from monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), triethanolamine (TEA), diglycolamine (DGA), isopropanolamines such as monoisopropanolamine (MIPA), diisopropanolamine (DIPA) and triisopropanolamine (TIPA), ethylene amines such as ethylenediamine (EDA), Diethylene triamine (DETA), triethylene tetramine (TETA) and tetraethylene pentamine (TEPA), cyclamines such as cyclohexylamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof.

[0100] According to a preferred embodiment, the lubricating composition comprises: - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably still from 0.5 to 7% by weight, of acid(s), and - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably still from 1 to 7% by weight of base(s),

[0101] relative to the total weight of the lubricating composition.

[0102] According to a preferred embodiment, the lubricating composition comprises: - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably still from 0.5 to 7% by weight, of aliphatic carboxylic acid(s), and - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably still from 1 to 7% by weight of amine(s),

[0103] relative to the total weight of the lubricating composition.

[0104] According to a preferred embodiment, the lubricating composition comprises: - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably even more from 1 to 7% by weight, of monocarboxylic aliphatic acid(s), and - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably still from 1 to 7% by weight of alkanolamine(s),

[0105] relative to the total weight of the lubricating composition.

[0106] According to a preferred embodiment, the lubricating composition comprises: - from 0.05 to 10% by weight, preferably from 0.1 to 7% by weight, preferably again from 0.5 to 5% by weight, of monocarboxylic aliphatic acid(s) comprising from 4 to 15 carbon atoms, and - from 0.05 to 10% by weight, preferably from 0.1 to 10% by weight, preferably again from 1 to 10% by weight of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-l,3-propanediol, 2-amino-2-methyl-l-propanol and mixtures thereof,

[0107] relative to the total weight of the lubricating composition.

[0108] According to a preferred embodiment, the lubricating composition comprises: - from 0.05 to 10% by weight, preferably from 0.1 to 7% by weight, preferably even more from 0.5 to 5% by weight, of saturated monocarboxylic aliphatic acid(s) comprising from 4 to 15 carbon atoms, and - from 0.05 to 10% by weight, preferably from 0.1 to 10% by weight, preferably further 1 to 10% by weight of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-l,3-propanediol, 2-amino-2-methyl-l-propanol and mixtures thereof,

[0109] relative to the total weight of the lubricating composition.

[0110] According to one embodiment, the acid / base mass ratio of the anti-corrosion system ranges from 0.1 to 2, preferably from 0.2 to 1, and even more preferably from 0.3 to 0.8.

[0111] Preferably, the anti-corrosion system is chosen so as to maintain the pH of the lubricating composition at an alkaline pH, i.e. a pH ranging from 8 to 11, preferably from 8 to 10.

[0112] The acid-base anti-corrosion system represents from 0.1 to 30% by weight, preferably from 1 to 30% by weight, of the total weight of the lubricating composition (reduced to 100% by weight). Lubricant composition

[0113] The lubricating composition according to the invention is an aqueous lubricating composition. Water can represent from 10 to 95% by weight of the total weight of the lubricating composition.

[0114] When the composition is a ready-to-use composition, water preferably represents 40 to 95% by weight, preferably 50 to 90% by weight, of the total weight of the lubricating composition.

[0115] When the composition is a concentrated composition (to be diluted), water preferably represents 10 to 50% by weight, preferably 10 to 30% by weight, of the total weight of the lubricating composition.

[0116] The lubricating composition according to the invention may further comprise at least one additive selected from among the additives conventionally used by those skilled in the art in lubricating compositions for metalworking, preferably at least one additive selected from among antifoams, biocides, wetting agents, friction modifiers, antifreeze additives, anti-corrosion agents other than acid-base systems, and mixtures thereof.

[0117] According to one embodiment, the lubricating composition according to the invention further comprises at least one additive selected from antifoams, benzotriazole or tolyltriazole type anti-corrosion agents, and biocides, alone or in mixture, preferably in a total quantity from 0.01 to 5% by weight, preferably from 0.05 to 3% by weight, relative to the total weight of the lubricating composition.

[0118] According to one embodiment, the viscosity at 40°C of the lubricating composition ranges from 1 to 20 mm2 / s, preferably from 1.5 to 5 mm2 / s.

[0119] The viscosity at 40°C of the lubricating composition can be measured according to ASTM D7042.

[0120] According to one embodiment, the lubricating composition according to the invention comprises water and: - 1 to 60% by weight, preferably 5 to 60% by weight, of PAGs containing alkylene oxide motifs comprising 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, propoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - 0.1 to 30% by weight, preferably 1 to 30% by weight, of an anti-corrosion system comprising at least one acid and at least one base,

[0121] relative to the total weight of the lubricating composition.

[0122] According to one embodiment, the lubricating composition according to the invention includes water and: - 1 to 60% by weight, preferably 5 to 60% by weight, of PAGs containing alkylene oxide motifs comprising 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of aliphatic carboxylic acid(s), - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of amine(s),

[0123] relative to the total weight of the lubricating composition.

[0124] According to one embodiment, the lubricating composition according to the invention includes water and: - 1 to 60% by weight, preferably 5 to 60% by weight, of PAGs containing alkylene oxide motifs comprising 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of aliphatic carboxylic acid(s) composed of carbon, hydrogen and oxygen atoms, - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of amine(s),

[0125] relative to the total weight of the lubricating composition.

[0126] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAGs containing alkylene oxide motifs comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, the PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of aliphatic carboxylic acid(s), - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of amine(s),

[0127] relative to the total weight of the lubricating composition.

[0128] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAGs comprising alkylene oxide motifs comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, said PAGs being terminated by one or two identical or different alkyl terminal groups having from 1 to 5 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, said fatty alcohols comprising a hydrocarbon chain having from 6 to 24 carbon atoms, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferably still from 0.5 to 5% by weight, of aliphatic carboxylic acid(s), - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of amine(s),

[0129] relative to the total weight of the lubricating composition.

[0130] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAG comprising alkylene oxide motifs having from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of ali- acid(s) monocarboxylic phatic(s), and - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of alkanolamine(s),

[0131] relative to the total weight of the lubricating composition.

[0132] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAG comprising alkylene oxide motifs having from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of monocarboxylic aliphatic acid(s) comprising from 4 to 15 carbon atoms, and - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof,

[0133] relative to the total weight of the lubricating composition.

[0134] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAGs selected from diblock copolymers of ethylene oxide-propylene oxide and triblock copolymers of propylene oxide-ethylene oxide-propylene oxide and mixtures thereof, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of monocarboxylic aliphatic acid(s), and - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of alkanolamine(s),

[0135] relative to the total weight of the lubricating composition.

[0136] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAGs selected from diblock copolymers of ethylene oxide-propylene oxide and triblock copolymers of propylene oxide-ethylene oxide-propylene oxide and mixtures thereof, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of monocarboxylic aliphatic acid(s) comprising from 4 to 15 carbon atoms, and - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof,

[0137] relative to the total weight of the lubricating composition.

[0138] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAGs selected from diblock copolymers ethylene oxide-propylene oxide and triblock copolymers propylene oxide-ethylene oxide-propylene oxide and mixtures thereof, the PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of monocarboxylic aliphatic acid(s) comprising from 4 to 15 carbon atoms, and - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof,

[0139] relative to the total weight of the lubricating composition.

[0140] When the composition is a ready-to-use composition, according to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 30% by weight of PAGs chosen from diblock copolymers ethylene oxide-propylene oxide and triblock copolymers propylene oxide-ethylene oxide-propylene oxide and their mixtures, the PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 0.1 to 10% by weight of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and their mixture, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - from 0.05 to 10% by weight of monocarboxylic aliphatic acid(s) comprising 4 to 15 carbon atoms, and - from 0.05 to 10% by weight of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-l,3-propanediol, 2-amino-2-methyl-l-propanol and mixtures thereof,

[0141] relative to the total weight of the lubricating composition.

[0142] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 60% by weight, of PAGs comprising alkylene oxide motifs comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, said PAGs being terminated by one or two identical or different alkyl terminal groups having from 1 to 5 carbon atoms, - from 0.1 to 20% by weight, preferably from 0.1 to 15% by weight, of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, said fatty alcohols comprising a hydrocarbon chain having from 6 to 24 carbon atoms, - from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, of monocarboxylic aliphatic acid(s) comprising from 4 to 15 carbon atoms, and - from 0.05 to 15% by weight, preferably from 0.1 to 12% by weight, of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof,

[0143] relative to the total weight of the lubricating composition.

[0144] When the composition is a ready-to-use composition, according to one embodiment, the lubricating composition according to the invention comprises water and: from 1 to 30% by weight of PAGs comprising alkylene oxide motifs having from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, said PAGs being terminated by one or two identical or different alkyl terminal groups having from 1 to 5 carbon atoms, from 0.1 to 10% by weight of alkoxylated fatty alcohols selected from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols and mixtures thereof, said fatty alcohols comprising a hydrocarbon chain having from 6 to 24 carbon atoms, from 0.05 to 10% by weight of monocarboxylic aliphatic acid(s) comprising 4 to 15 carbon atoms, and from 0.05 to 10% by weight of alkanolamine(s) selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof,

[0145] relative to the total weight of the lubricating composition.

[0146] Preferably, the lubricating composition according to the invention is in the form of a solution. Indeed, the ingredients of the lubricating composition are preferably soluble or solubilized in water.

[0147] For the purposes of the present invention, a “solution” is distinguished from an emulsion or dispersion which may contain several phases or which may contain insolubilized particles.

[0148] According to one embodiment, the aqueous lubricating composition according to the invention is not an emulsion.

[0149] The lubricating composition according to the invention can be prepared by simply mixing the ingredients, according to any methods known to a person skilled in the art for obtaining a solution. Applications

[0150] The invention also relates to the use of the lubricating composition according to the invention, as a fluid for metalworking, in particular for the deformation of metal parts and / or for the forming of metal parts and / or for the cutting of metal parts and / or for the stamping of metal parts and / or for the rolling of metal parts, the metals being preferably chosen from steel and aluminum.

[0151] It should be noted that the lubricating composition may be diluted with water before its use as a fluid for metalworking.

[0152] The present invention also relates to a method of lubricating at least one metal surface of a metal part, in particular aluminium or steel, comprising bringing the lubricating composition into contact with said metal surface.

[0153] Preferably, the contact step is carried out by spraying the lubrication composition or by depositing the lubrication composition on the metal surface, the deposit being carried out for example using a roller or a brush.

[0154] Preferably, the metal surface is an aluminum or steel surface.

[0155] The metal parts are preferably of small thicknesses, for example of thicknesses less than or equal to 5 pm, preferably less than or equal to 3 pm, preferably still a thickness ranging from 0.35 to 1.5 pm.

[0156] It should be noted that the lubrication process may include a step of diluting the lubricating composition with water before the step of bringing the lubricating composition (thus diluted) into contact with said metal surface.

[0157] The inventors have indeed observed that the combination of PAG, alkoxylated fatty alcohol and an acid-base anti-corrosion system made it possible to obtain a lubricating composition having reduced or even zero VOC emissions even when heated to 80°C, said composition having excellent lubrication properties for metalworking, and in particular for metal deformation.

[0158] The lubricating composition according to the invention thus presents a universality in that it can be used both for the deformation of steel and for the deformation of aluminum.

[0159] According to one embodiment, the lubrication process further includes a heat treatment step for the metal part, after the contact step. For example, the heat treatment could be heating to a temperature of at least 150°C, or even at least 200°C or at least 300°C. This embodiment, including a heat treatment step, is particularly well suited when the metal part is made of aluminum.

[0160] The lubricating composition according to the invention can also be implemented to provide deformed metal parts without staining said metal part, in particular when the part is made of aluminum.

[0161] The PAG(s) implemented in the aforementioned use may exhibit one or more of the characteristics and preferences described above within the framework of the lubricating composition according to the invention.

[0162] The alkoxylated fatty alcohol(s) in the aforementioned use may exhibit a or several of the characteristics and preferences described above within the framework of the lubricating composition according to the invention.

[0163] The anti-corrosion system in the aforementioned use may have one or more of the characteristics and preferences described above within the framework of the lubricating composition according to the invention.

[0164] The resulting lubricating composition from the aforementioned use may exhibit one or more of the characteristics and preferences described above within the framework of the lubricating composition according to the invention. EXAMPLES

[0165] In the remainder of this description, examples are given by way of illustration of the present invention and are not intended in any way to limit its scope.

[0166] In the examples, the following ingredients were used: - PAG1 designates a linear poly(alkylene glycol) comprising ethylene oxide (OE) and propylene oxide (OP) motifs in an OE / OP ratio of approximately 1 / 1, PAG1 being terminated by methyl and butyl groups, PAG1 having a molecular mass ranging from 1000 to 2000 g / mol. - PAG2 designates a poly(alkylene glycol) comprising ethylene oxide (OE) and propylene oxide (OP) motifs in an OE / OP ratio of approximately 1 / 1, PAG2 being terminated by a butyl group at one end and a hydroxyl group at the other end, PAG2 having a molecular mass ranging from 1000 to 2000 g / mol. - PAG3 designates a poly(alkylene glycol) comprising ethylene oxide (OE) and propylene oxide (OP) motifs, PAG3 being terminated by an alkyl group at one end and a hydroxyl group at the other end, PAG3 having a molecular mass ranging from 1000 to 2500 g / mol. - alkoxylated fatty alcohol refers to one or more alcohols comprising propoxylated and / or ethoxylated motifs and an aliphatic hydrocarbon chain comprising 12-14 carbon atoms. - alkanolamine means one or more alkanolamines selected from monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), monoisopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-l,3-propanediol, 2-amino-2-methyl-l-propanol and mixtures thereof. - C8-C10 aliphatic monoacid refers to one or more aliphatic monocarboxylic acids having 8 to 10 carbon atoms. - C8-C10 aliphatic diacid refers to one or more dicarboxylic acids

[0167]

[0168]

[0169]

[0170]

[0171]

[0172] aliphatic having 8 to 10 carbon atoms. - triazine-derived salt is a system comprising a triacid fatty acid salt derived from 1,3,5-triazine. - additive package refers to a mixture of additives commonly used in lubricating compositions for metalworking, including in particular an antifoam and a benzotriazole-type anti-corrosion agent. Example 1: Measuring VOC emissions In this example, a lubricating composition according to the invention was compared to two organic solvent-based lubricating compositions used for the deformation of metal parts. Table 1 gives details of the compositions tested; the percentages are percentages by weight relative to the total weight of the composition. [Tables 1] CCI CC2 Cil Mineral oil of petroleum origin 76% Ester 24% 24% Isoparaffinic oil of petroleum origin 76% Water 70.74% PAG1 10% PAG2 10% Alkoxylated fatty alcohol 1% Alkanolamine 4.6% C7-C11 aliphatic monoacid 3% Additives package 0.66% The tests were carried out in accordance with the EN NF 12619 standard, by weighing 3g of product, and testing two temperatures: 30°C and 80°C. Total VOC emissions, converted to ppm, are shown in Table 2 for the three compositions tested and for the two temperatures tested.

[0173] [Tables2] CCI CC2 Cil VOC emissions at 30°C 19 216 0 VOC emissions at 80°C 441 2404 0

[0174] The results in Table 2 show that the lubricant composition according to the invention has zero VOC emissions, even at 80°C.

[0175] Example 2: Staining tests on aluminium plates

[0176] In this example, staining tests were set up to determine the staining power of the lubricating composition with respect to an aluminum part.

[0177] Table 3 shows the details of the lubricant compositions tested in this example.

[0178] [Tables3] CC3 CI2 CI3 Water 72.95% 70.45% 70.45% PAG1 5% 5% PAG2 15% 15% PAG3 20% Alkoxylated Fatty Alcohol 1% 1% Castor Oil 5% Triazine Derivative Salt 1.5% Alkanolamine 4.6% 4.6% C7-C11 Aliphatic Monoacid 3% C7-C11 Aliphatic Diacid 3% Additive Package 0.55 0.95% 0.95%

[0179] Staining is assessed by spraying the lubricating composition onto an aluminum plate and placing said plate in an oven heated to 350°C and maintaining the plate at 350°C for 10 minutes. The level of staining is assessed by assigning a score from 0 (no stain) to 5 (heavily stained).

[0180] The Cil composition described in Table 1 and the compositions in Table 3 were evaluated and the results are shown in Table 4.

[0181] [Tables 4] CC3 Eyelash CI2 CI3 Staining notes 5 0 0 3

Claims

Claims

1. Lubricating composition comprising water and: - from 1 to 60% by weight of polyalkylene glycol, - from 0.1 to 30% by weight of alkoxylated fatty alcohol(s), - from 0.1 to 30% by weight of an anti-corrosion system comprising at least one monocarboxylic acid and at least one amine, relative to the total weight of the lubricating composition.

2. Lubricating composition according to claim 1, comprising water and: - from 1 to 60% by weight of polyalkylene glycol comprising alkylene oxide units comprising from 2 to 8 carbon atoms, - from 0.1 to 20% by weight of ethoxylated and / or propoxylated fatty alcohol(s), - from 0.1 to 30% by weight of an anti-corrosion system comprising at least one monocarboxylic acid and at least one amine, relative to the total weight of the lubricating composition.

3. Lubricating composition according to claim 1 or 2, said composition being a ready-to-use composition comprising water and: - from 1 to 30% by weight of polyalkylene glycol, - from 0.1 to 10% by weight of ethoxylated and / or propoxylated fatty alcohol(s), - from 0.1 to 15% by weight of the anti-corrosion system, relative to the total weight of the lubricating composition.

4. Lubricating composition according to claim 1 or 2, said composition being a concentrated composition comprising water and: - from 30 to 60% by weight of polyalkylene glycol, - from 1 to 15% by weight of ethoxylated and / or propoxylated fatty alcohol(s), - from 10 to 30% by weight of the anti-corrosion system, relative to the total weight of the lubricating composition.

5. A lubricating composition according to any one of claims 1 to 4, wherein said amine is selected from alkanolamines, preferably from monoethanolamine, diethanolamine, triethanolamine, diglycolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, methyldiethanolamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof.

6. Lubricating composition according to any one of claims 1 to 5, in which the polyalkylene glycol(s) are chosen from poly(ethylene glycol), poly(propylene glycol), block copolymers comprising ethylene oxide units and propylene oxide units, and mixtures thereof, preferably from block copolymers comprising ethylene oxide units and propylene oxide units and mixtures thereof, more preferably from ethylene oxide-propylene oxide diblock copolymers and propylene oxide-ethylene oxide-propylene oxide triblock copolymers and mixtures thereof.

7. A lubricating composition according to any one of claims 1 to 6, wherein each polyalkylene glycol has a molecular weight ranging from 500 to 10000 g / mol, preferably from 800 to 5000 g / mol, more preferably from 1000 to 3000 g / mol.

8. A lubricating composition according to any one of claims 1 to 7, wherein each polyalkylene glycol has a viscosity at 40°C ranging from 10 to 1000 mm2 / s, preferably from 15 to 500 mm2 / s, more preferably from 20 to 400 mm2 / s.

9. Lubricating composition according to any one of claims 1 to 8, in which the alkoxylated fatty alcohol(s) are chosen from ethoxylated fatty alcohols, ethoxylated and proproxylated fatty alcohols, and a mixture thereof.

10. A lubricating composition according to any one of claims 1 to 9, wherein each alkoxylated fatty alcohol comprises from 1 to 20 alkoxylated units and / or a hydrocarbon chain comprising from 6 to 24 carbon atoms.

11. A lubricating composition according to any one of claims 1 to 3 and 5 to 10, said composition being a ready-to-use composition comprising water and: from 5 to 30% by weight of PAG chosen from copolymers ethylene oxide-propylene oxide diblock and propylene oxide-ethylene oxide-propylene oxide triblock copolymers and mixtures thereof, PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 0.1 to 10% by weight of alkoxylated fatty alcohols chosen from ethoxylated fatty alcohols, ethoxylated and pro-proxylated fatty alcohols and their mixture, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - from 0.05 to 10% by weight of monocarboxylic aliphatic acid(s) containing from 4 to 15 carbon atoms, and - from 0.05 to 10% by weight of alkanolamine(s) chosen from monoethanolamine, diethanolamine, triethanolamine, diglycolamine, monoisopropanolamine, dii-sopropanolamine, triisopropanolamine, methyldiethanolamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof, relative to the total weight of the lubricating composition.

12. A lubricating composition according to any one of claims 1 to 2 and 4 to 10, said composition being a concentrated composition comprising water and: - from 30 to 60% by weight of PAG chosen from ethylene oxide-propylene oxide diblock copolymers and propylene oxide-ethylene oxide-propylene oxide triblock copolymers and mixtures thereof, the PAGs having a molecular mass ranging from 1000 to 3000 g / mol, - from 1 to 10% by weight of alkoxylated fatty alcohols chosen from ethoxylated fatty alcohols, ethoxylated and pro-proxylated fatty alcohols and their mixture, said alkoxylated fatty alcohols having a molar mass ranging from 100 to 900 g / mol, - from 5 to 15% by weight of monocarboxylic aliphatic acid(s) containing from 4 to 15 carbon atoms, and - from 5 to 15% by weight of alkanolamine(s) chosen from monoethanolamine, diethanolamine, triethanolamine, diglycolamine, monoisopropanolamine, dii-sopropanolamine, triisopropanolamine, methyldiethanolamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-l-propanol and mixtures thereof, relative to the total weight of the lubricating composition.

13. Use of the lubricating composition according to any one of claims 1 to 12, as a fluid for metalworking, in particular for deforming metals and / or for forming metals and / or for cutting metals and / or for stamping metals and / or for rolling metals, the metals preferably being chosen from steel and aluminum.

14. Use according to claim 13, in which the emissions of total volatile organic compounds at 80°C according to standard NF EN 12619 are less than 200 ppm, preferably less than 150 ppm, more preferably less than 100 ppm, or even less than 50 ppm.