WATER-BASED LUBRICANT FOR METALWORKING

Abstract

The invention relates to a lubricating composition comprising water and: - 1 to 60% by weight of poly(alkylene glycol), - 0.5 to 30% by weight of polyetheramine, relative to the total weight of the lubricating composition. The invention also relates to the use of said lubricating composition as a fluid for metalworking, the metals being preferably selected from steel and aluminum.

Description

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

[0001] The invention relates to an aqueous lubricant intended to be used for metalworking, in particular for machining (turning, milling, drilling, sawing, threading among others), forming, cutting, stamping or even rolling of metal parts, in particular made of aluminum or steel. STATE OF THE ART

[0002] Lubricants are traditionally used for metalworking. There are aqueous lubricants and non-aqueous lubricants, also called organic lubricants.

[0003] The water-based formulations currently on the market are generally in emulsion form and do not generally meet all the expectations for machining metal parts, particularly aluminum, from the point of view of part quality, performance (speed, feed), tool life. Tests carried out with products intended primarily for steel may have limitations on aluminum, a softer material requiring the addition of specific additives.

[0004] Aqueous fluids comprising poly(alkylene glycol) exist. They generally do not meet all the expectations of manufacturers for use in both steel and aluminum.

[0005] The present invention provides a lubricating composition having improved lubricating properties for the machining of metal parts, in particular aluminum and steel, but also for the forming, cutting, stamping or even rolling of metal parts. Summary of the invention

[0006] The invention relates to a lubricating composition comprising water and: - from 1 to 60% by weight of poly(alkylene glycol), - from 0.5 to 30% by weight of polyetheramine, relative to the total weight of the lubricating composition.

[0007] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 5 to 50% by weight of poly(alkylene glycol) comprising alkylene oxide units containing from 2 to 16 carbon atoms, preferably from 2 to 8 carbon atoms, - from 1 to 20% by weight of polyetheramine chosen from monoamines, diamines and triamines comprising units chosen from alkylene oxides comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, relative to the total weight of the lubricating composition.

[0008] According to one embodiment, the lubricating composition according to the invention further comprises at least one additive chosen from alkaline bases, alkanolamines and their mixtures,

[0009] the alkanolamines being preferably chosen 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, and

[0010] the alkaline bases being preferably chosen from potassium hydroxide and sodium hydroxide.

[0011] Preferably, the poly(alkylene glycol) is(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 or ethylene oxide-propylene oxide-ethylene oxide triblock copolymers, and mixtures thereof.

[0012] According to one embodiment, each poly(alkylene glycol) has a molecular mass ranging from 500 to 10,000 g / mol, preferably from 800 to 5,000 g / mol, more preferably from 1,100 to 3,000 g / mol.

[0013] According to one embodiment, each poly(alkylene 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.

[0014] According to one embodiment, the polyetheramine(s) are chosen from monoamines comprising ethylene oxide units and / or propylene oxide units, diamines comprising ethylene oxide units and / or propylene oxide units, and mixtures thereof, preferably from diamines comprising ethylene oxide units and / or propylene oxide units.

[0015] According to one embodiment, each polyetheramine has a molecular mass ranging from 500 to 5000 g / mol, preferably from 1000 to 3000 g / mol.

[0016] The invention also relates to the use of the lubricating composition according to the invention as a fluid for working metals, the metals preferably being chosen from steel and aluminum.

[0017] Preferably, the composition is used for machining metals and / or for forming and / or for cutting and / or for stamping and / or for rolling of metals.

[0018] The invention also relates to the use of 0.5 to 30% by weight of polyetheramines in a lubricating composition comprising water and 1 to 60% by weight of poly(alkylene glycol), relative to the total weight of the lubricating composition, for improving the lubricating properties during metalworking using said lubricating composition.

[0019] Preferably, the lubricating composition is as defined in the present invention.

[0020] According to one embodiment, the 0.5 to 30% by weight of polyetheramines are used to improve the lubricating properties of the lubricating composition during machining and / or during forming and / or during cutting, and / or during stamping and / or during rolling of metals.

[0021] The invention makes it possible to provide a multi-service lubricating composition since it can be applied indifferently to aluminum surfaces and steel surfaces.

[0022] The invention makes it possible to provide a lubricating composition having a good toxicological profile and a low impact on the environment.

[0023] The invention makes it possible to provide a lubricating composition which does not generate oil deposits on the ground, which increases operator safety.

[0024] The lubricating composition according to the invention has improved lubricating properties, on aluminum but also on steel. DETAILED DESCRIPTION OF THE INVENTION

[0025] The invention relates to a lubricating composition comprising water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, of polyalkylene glycol, from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of polyetheramine, relative to the total weight of the lubricating composition, said lubricating composition being able to be in the form of a solution or in the form of an emulsion, preferably in the form of a solution. Polyalkylene glycol (PAG)

[0026] According to one embodiment, the PAG(s) of the lubricating composition according to the invention are chosen from PAGs comprising alkylene oxide units comprising from 2 to 16 carbon atoms, preferably from 2 to 8 carbon atoms, more preferably from 2 to 4.

[0027] According to one embodiment, the PAG(s) used in the lu- composition The polishing agent according to the invention corresponds to formula (I):

[0028] R-(OA)ZOH (I)

[0029] in which:

[0030] R represents a hydrogen atom or alkyl group, linear or branched, comprising from 1 to 5 carbon atoms;

[0031] A, all identical or different, represents an alkyl group, linear or branched, comprising from 2 to 16 carbon atoms, preferably from 2 to 8 carbon atoms, more preferably from 2 to 4;

[0032] z represents an integer greater than or equal to 2, preferably an integer greater than or equal to 4.

[0033] 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 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.

[0034] By "block copolymers comprising ethylene oxide units and propylene oxide units" within the meaning of the present invention, we mean 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 can then be called PEG / PPG.

[0035] For the purposes of the present invention, the term "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.

[0036] For the purposes of the present invention, the term "propylene oxide-ethylene oxide-propylene oxide triblock copolymers" means copolymers consisting of three blocks, sequenced, 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 this order). They can then be called PPG-PEG-PPG.

[0037] The PAG(s) used in the invention may optionally comprise alkyl end groups, for example chosen from linear or branched alkyl groups comprising from 1 to 5 carbon atoms. Preferably, the PAG(s) used in the invention do not comprise such alkyl end groups.

[0038] According to one embodiment, the lubricating composition comprises at least one PAG comprising -OCH2CH2- units and -OCH2CH(CH3)- units such that the ratio mass ratio between the OCH2CH2 units and the OCH2CH(CH3) units ranges from 0.1 to 0.9, preferably from 0.2 to 0.7, more preferably from 0.25 to 0.5.

[0039] 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):

[0040] R-(OCH2CH2)x(OCH2CH(CH3))yOH (II);

[0041] R-(OCH2CH(CH3))y(OCH2CH2)xOH (III);

[0042] R-(OCH2CH(CH3))y(OCH2CH2)x(OCH2CH(CH3))y OH (IV);

[0043] R-(OCH2CH2)x(OCH2CH(CH3))y(OCH2CH2)x OH (V);

[0044] in which:

[0045] R represents a hydrogen atom or a saturated, linear or branched alkyl group comprising from 1 to 5 carbon atoms;

[0046] x and x', identical or different, represents an integer greater than or equal to 2, preferably greater than or equal to 4,

[0047] y and y', identical or different, represents an integer greater than or equal to 2.

[0048] Preferably, in the 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.

[0049] Preferably, in formula (IV), x is an integer ranging from 2 to 30, preferably from 4 to 25, advantageously from 6 to 20, and the sum y+y' ranges from 8 to 45, preferably from 12 to 40, more preferably from 20 to 35.

[0050] Preferably, in formula (V), y is an integer ranging from 2 to 30, preferably from 4 to 25, advantageously from 6 to 20, and the sum x+x' ranges from 8 to 45, preferably from 12 to 40, more preferably from 20 to 35.

[0051] Preferably, in the compounds of formula (II), (III), (IV) or (V) of the PAG entering into the lubricating composition according to the invention, R is a hydrogen atom.

[0052] According to one embodiment, each PAG included in the lubricating composition according to the invention corresponds to formula (IV) in which R is a hydrogen atom, where x, y and y' are each independently of one another chosen from integers ranging from 6 to 20 and the sum y+y' ranges from 20 to 35.

[0053] According to one embodiment, each PAG included in the lubricating composition according to the invention has a molecular mass ranging from 500 to 10,000 g / mol, preferably from 800 to 5,000 g / mol, more preferably from 1,100 to 3,000 g / mol.

[0054] According to one embodiment, each PAG included in the lubricating composition according to the invention 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.

[0055] Viscosity at 40°C can be measured according to ASTM D7042.

[0056] 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 below -20°C.

[0057] The pour point can be measured according to ISO 3016.

[0058] The PAG(s) represent from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight of the total weight of the lubricating composition (reduced to 100% by weight).

[0059] PAGs are commercially available products. Polyetheramine (PEA)

[0060] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention are chosen from monoamines, diamines and triamines comprising one or more units chosen from alkylene oxides comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms.

[0061] In the context of the present invention, the PEA(s) entering into the lubricating composition are different from the PAG(s) entering into the lubricating composition.

[0062] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention are chosen from monoamines comprising ethylene oxide units and / or propylene oxide units, diamines comprising ethylene oxide units and / or propylene oxide units, and mixtures thereof, preferably from diamines comprising ethylene oxide units and / or propylene oxide units.

[0063] By "monoamine comprising ethylene oxide units and / or propylene oxide units" within the meaning of the present invention, is meant a compound comprising a single amine function and comprising (i) a block resulting from the polymerization of ethylene glycol and / or (ii) a block resulting from the polymerization of propylene glycol.

[0064] By "diamine comprising ethylene oxide units and / or propylene oxide units" within the meaning of the present invention, is meant a compound comprising exactly two amine functions and comprising (i) a block resulting from the polymerization of ethylene glycol and / or (ii) a block resulting from the polymerization of propylene glycol.

[0065] Preferably, the PEA(s) included in the lubricating composition according to the invention are chosen from primary amines.

[0066] According to a particular embodiment, the PEA(s) included in the lubricating composition according to the invention are chosen from diamines comprising ethylene oxide units and propylene oxide units.

[0067] By "diamine comprising ethylene oxide units and / or propylene oxide units" within the meaning of the present invention, is meant a compound comprising exactly two amine functions and comprising (i) a block resulting from the polymerization of ethylene glycol and (ii) a block resulting from the polymerization of propylene glycol.

[0068] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention corresponds to the formula (VI), (VIbis) (VII), (Vllbis), (VIII), (VlIIbis), (IX) and / or (X):

[0069] H3C-(OCH2CH2)r(OCH2CH(CH3))s-NH2 (VI)

[0070] H3C-(OCH2CH(CH3))s-(OCH2CH2)r-NH2 (VIbis)

[0071] H2N-CH(CH3)-CH2 (OCH2CH(CH3))t-NH2 (VII)

[0072] H2N-CH(CH3)-CH2-(OCH2CH2)r-NH2 (Vllbis)

[0073] H2N-CH(CH3)-CH2(OCH2CH(CH3))u(OCH2CH2)v(OCH2CH(CH3))w-NH2(VIII)

[0074] H2N-CH(CH3)-CH2 (OCH2CH2)U(OCH2CH(CH3))V(OCH2CH2)W-NH2 (VlIIbis)

[0075] H3C-(OCH2CH2)r-NH2(IX)

[0076] H3C-(OCH2CH(CH3))t-NH2(X)

[0077] in which:

[0078] r represents an integer greater than or equal to 2, preferably greater than or equal to 5, more preferably greater than or equal to 8;

[0079] s represents an integer greater than or equal to 2, preferably greater than or equal to 5, more preferably greater than or equal to 8;

[0080] t represents an integer greater than or equal to 6, preferably greater than or equal to 10, more preferably greater than or equal to 15;

[0081] u represents an integer greater than or equal to 2, preferably greater than or equal to 5, more preferably greater than or equal to 8;

[0082] v represents an integer greater than or equal to 2, preferably greater than or equal to 5, more preferably greater than or equal to 8;

[0083] w represents an integer greater than or equal to 2, preferably greater than or equal to 5, more preferably greater than or equal to 8;

[0084] it being understood that:

[0085] r+s is greater than or equal to 6, preferably greater than or equal to 10, more preferably greater than or equal to 15 in formula (VI) and (VIbis) and that:

[0086] u+v+w is greater than or equal to 6, preferably greater than or equal to 10, more preferably greater than or equal to 15 in formula (VIII) and (VlIIbis).

[0087] The PEA used in the lubricating composition according to the invention may comprise a mixture of PEA, in particular a mixture of PEA of formula (VI), (VIbis) (VII), (Vllbis), (VIII), (VlIIbis), (IX) and / or (X).

[0088] According to one embodiment, the lubricating composition according to the invention comprises at least one PEA corresponding to one of the formulas (VI), (VII) or (VIII).

[0089] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention comprises at least 50% by weight of PEA corresponding to formula (VI), (VII) and / or (VIII), relative to the total weight of the PEA(s).

[0090] According to one embodiment, the PEA(s) entering into the lubricating composition according to the invention comprises, relative to the total weight of the PEA(s), at least 50% by weight, preferably at least 70% by weight, preferably at least 90% by weight, of PEA corresponding to formula (VII), preferably in which t is an integer ranging from 6 to 70, preferably from 10 to 60, more preferably from 15 to 50.

[0091] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention comprises, relative to the total weight of the PEA(s), at least 50% by weight, preferably at least 70% by weight, preferably at least 90% by weight, of PEA corresponding to formula (VI), preferably in which r and s are such that the molecular mass ranges from 1000 to 3000 g / mol.

[0092] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention corresponds to formula (VII), preferably in which t is an integer ranging from 6 to 70, preferably from 10 to 60, more preferably from 15 to 50.

[0093] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention corresponds to formula (VI), preferably in which r and s are such that the molecular mass ranges from 1000 to 3000 g / mol.

[0094] According to one embodiment, the PEA(s) included in the lubricating composition according to the invention has a molecular mass ranging from 500 to 5000 g / mol, preferably from 1000 to 3000 g / mol.

[0095] The PEA(s) represent from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of the total weight of the lubricating composition (reduced to 100% by weight).

[0096] PEAs are commercially available products. Lubricating composition

[0097] The lubricating composition according to the invention is an aqueous lubricating composition. The water may represent from 10 to 90% by weight of the total weight of the lubricating composition or from 20 to 60% by weight of the total weight of the lubricating composition.

[0098] The lubricating composition may be in the form of a solution or an emulsion.

[0099] If the composition is in the form of an emulsion, it will typically be an oil-in-water emulsion when used for metalworking, the oil being able to be chosen from mineral oils, vegetable oils, animal oils.

[0100] Depending on the embodiment where the lubricating composition is in the form of an emulsion, the oil portion of the emulsion will typically represent from 1 to 60% by weight, preferably from 5 to 40% by weight, of the weight of the lubricating composition.

[0101] According to a preferred embodiment, the lubricating composition according to the invention is in the form of a solution. Indeed, the ingredients of the lubricating composition are preferably chosen such that they are soluble or solubilized in water.

[0102] For the purposes of the present invention, a “solution” contains a single phase and is distinguished from an emulsion which may contain several phases and is distinguished from a dispersion which may contain non-solubilized particles.

[0103] Thus, according to a preferred embodiment, the aqueous lubricating composition according to the invention is not in the form of an emulsion.

[0104] The lubricating composition according to the invention may further comprise at least one additive chosen from the additives conventionally used by those skilled in the art in lubricating compositions for metalworking, preferably at least one additive chosen from pH regulators, anti-corrosion agents, anti-foam agents, biocides, wetting agents, friction modifiers, antifreeze additives, preferably anti-foam agents and biocides, alone or as a mixture.

[0105] According to one embodiment, the lubricating composition according to the invention further comprises at least one pH regulating additive, in particular an alkaline buffer. The pH regulator makes it possible to maintain the desired pH of the lubricating composition, in particular in order to preserve an alkaline pH, advantageously between 8 and 11, in particular so as to prevent corrosion of the metal surfaces.

[0106] The pH regulator can be chosen from the family of amines, in particular alkanolamines and amino alcohols or from the family of alkaline bases.

[0107] It may in particular be a pH regulating additive chosen from ethanolamines, such as monoethanolamine (MEA), diethanolamine (DEA); triethanolamine (TEA), diglycolamine (DGA); isopropanolamines, such as monoisopropanolamine (MIPA), diisopropanolamine (DIPA) and triisopropanolamine (TIPA), ethylene amines, such as ethylene diamine (EDA), diethylene triamine (DETA), triethylene tetramine (TETA) and tetraethylene pentamine (TEPA), alkanolamines, such as methyldiethanolamine (MDEA), cyclamines, such as cyclohexylamine, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof.

[0108] According to one embodiment, the lubricating composition further comprises at least one additive chosen from alkaline bases, alkanolamines and their mixtures,

[0109] the alkanolamines being preferably chosen 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, and

[0110] the alkaline bases being preferably chosen from potassium hydroxide and sodium hydroxide.

[0111] According to one embodiment, the lubricating composition comprises from 1 to 50% by weight of a pH regulating additive, preferably from 10 to 40% by weight, relative to the total weight of the lubricating composition, said pH regulating additive preferably being chosen from amines, preferably from alkanolamines, such as monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), di-glycolamine (DGA), mono-isopropanolamine (MIPA), diisopropanolamine (DIPA), triisopropanolamine (TIPA), methyldiethanolamine (MDEA), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol and mixtures thereof.

[0112] According to one embodiment, the lubricating composition comprises at least one corrosion inhibitor, preferably at least one organic corrosion inhibitor.

[0113] Among the organic corrosion inhibitors that may be mentioned are aliphatic monocarboxylic acids, in particular having from 4 to 15 carbon atoms, for example octanoic acid, aliphatic dicarboxylic acids having from 4 to 15 carbon atoms, for example decane dioic acid (sebacic acid), undecane dioic acid, dodecane dioic acid, isononanoic acid or mixtures thereof, polycarboxylic acids optionally neutralized by triethanolamine, such as 1,3,5-triazine-2,4,6-tri-(6-aminocaproic) acid, alkanoylamidocarboxylic acids, in particular isononanoylamidocaproic acid, 6-[[(4-methylphenyl)sulfonyl]amino]hexanoic acid, and mixtures thereof. Borated amides, products of the reaction of amines or amino alcohols with boric acid, can also be used.

[0114] An aqueous lubricating composition according to the invention may in particular comprise from 0.01% to 15% by weight of corrosion inhibitor(s), preferably from 1.0% to 13% by weight, relative to the total weight of the composition.

[0115] According to one embodiment, the mass ratio between the proportion of PAG and the proportion of PEA (PAG / PEA) is greater than or equal to 1, preferably greater than or equal to 2.

[0116] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, of PAG comprising alkylene oxide units comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, - from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of PEA chosen from monoamines, diamines and triamines comprising units chosen from alkylene oxides comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms,

[0117] relative to the total weight of the lubricating composition.

[0118] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight of PAG comprising alkylene oxide units containing from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, - from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of PEA chosen from monoamines, diamines and triamines comprising units chosen from alkylene oxides comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, - from 1 to 50% by weight, preferably from 10 to 40% by weight, more preferably from 15 to 35% by weight, of amines, other than a PEA, said amine possibly being an alkanolamine, for example chosen 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,

[0119] relative to the total weight of the lubricating composition.

[0120] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, of PAGs chosen from ethylene oxide-propylene oxide diblock copolymers and propylene oxide-ethylene oxide-propylene oxide triblock copolymers and mixtures thereof, - from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of PEA chosen from diamines comprising ethylene oxide units and / or propylene oxide units,

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

[0122] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, of PAGs chosen from ethylene oxide-propylene oxide diblock copolymers and propylene oxide-ethylene oxide-propylene oxide triblock copolymers and mixtures thereof, - from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of PEA chosen from diamines comprising ethylene oxide units and / or propylene oxide units, - from 1 to 50% by weight, preferably from 10 to 40% by weight, more preferably from 15 to 35% by weight, of amines, other than a PEA, said amine which may be an alkanolamine, for example chosen 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,

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

[0124] According to one embodiment, the lubricating composition according to the invention comprises water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, of PAG corresponding to the formula (Ilbis):

[0125] H-(OCH2CH2)xx(OCH2CH(CH3))yyOH (Ilbis);

[0126] in which:

[0127] xx and yy are integers greater than or equal to 0 such that the PAG has a molecular mass ranging from 1000 to 3000 g / mol; - from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of PEA corresponding to formula (IV) or formula (VI) as defined above in which the integers r, s and t are such that the molecular mass of the PEA ranges from 1000 to 3000 g / mol;

[0128] relative to the total weight of the lubricating composition.

[0129] According to one embodiment, the lubricating composition according to the invention includes water and: - from 1 to 60% by weight, preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, of PAG corresponding to the formula (IVbis):

[0130] H-(OCH2CH(CH3))yy(OCH2CH2)xx(OCH2CH(CH3))yy OH (IVbis);

[0131] in which:

[0132] xx, yy and yy' are integers ranging from 6 to 20,

[0133] the sum yy+yy' goes from 20 to 35,

[0134] xx, yy and yy' are such that the PAG has a molecular mass ranging from 1000 to 3000 g / mol and such that the mass ratio between the OCH2CH2 units and the OCH2CH(CH3) units ranges from 0.2 to 0.7; - from 0.5 to 30% by weight, preferably from 1 to 20% by weight, more preferably from 2 to 15% by weight, of PEA corresponding to formula (VI) or formula (VII) as defined above in which the integers r, s and t are such that the molecular mass of the PEA ranges from 1000 to 3000 g / mol;

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

[0136] Preferably, the aqueous lubricating composition is substantially free of metal particles, in particular free of non-soluble metal particles. bilized at room temperature.

[0137] The lubricating composition according to the invention can be prepared by simply mixing the ingredients, according to any method known to those skilled in the art to obtain a solution. If the composition comprises a biocide and / or an anti-foam, said biocide and said anti-foam are preferably added at the end of the preparation of the composition. Applications

[0138] The invention also relates to the use of the lubricating composition according to the invention, as a fluid for working metals, in particular for machining metals (including in particular turning, milling, drilling, sawing, or even threading), forming metals, cutting metals, stamping metals or even rolling metals, these metals preferably being chosen from steel and aluminum.

[0139] The lubricating composition may optionally be diluted before use, in particular when used for machining metals.

[0140] The lubricating composition according to the present invention is particularly well suited for machining metals, in particular for turning, milling, drilling, sawing and / or threading.

[0141] The present invention also relates to a method for lubricating metal surfaces for working on these surfaces, in particular aluminum or steel, comprising bringing the lubricating composition according to the invention into contact with the metal surface, in particular aluminum or steel, for example by depositing the lubricating composition on the metal surface.

[0142] According to one embodiment, the lubrication method according to the invention further comprises a step of machining and / or forming and / or cutting and / or stamping and / or rolling said metal (coated with the lubricating composition), the machining including in particular turning, milling, drilling, sawing, or even threading. Preferably, said additional step is a step of machining metals, in particular turning, milling, drilling, sawing and / or threading.

[0143] The inventors have in fact observed that the combination of a PAG and a PEA makes it possible to obtain a lubricating composition having excellent lubricating properties for metalworking, and in particular for steel and aluminum.

[0144] The lubricating composition according to the invention thus has universality in that it can be used both for machining steel and for machining aluminum.

[0145] The lubricating composition according to the invention thus has an excellent service life and a very high usage cycle, notably higher than the fluids of the state of the art based on mineral oil.

[0146] The invention also relates to the use of 0.5 to 30% by weight of polyetheramines (PEA) in a lubricating composition comprising water and 1 to 60% by weight of polyalkylene glycol (PAG), relative to the total weight of the lubricating composition, for improving the lubricating properties of a metal surface, such as an aluminum or steel surface. In particular, the use of PEA in a solution comprising water and PAG makes it possible to reduce the power generated during metalworking.

[0147] The PEA(s) used in the aforementioned use may have one or more of the characteristics and preferences described above in the context of the lubricating composition according to the invention.

[0148] The PAG(s) used in the aforementioned use may have one or more of the characteristics and preferences described above in the context of the lubricating composition according to the invention.

[0149] The lubricating composition resulting from the aforementioned use may have one or more of the characteristics and preferences described above in the context of the lubricating composition according to the invention. EXAMPLES

[0150] In the remainder of this description, examples are given for the purpose of illustrating the present invention and are not intended in any way to limit its scope.

[0151] Example 1: Tests measuring the machining power drift required by the aluminum spindle to perform the operation

[0152] The lubricating compositions tested are detailed in Table 1. The percentages are expressed as percentages by weight relative to the total weight of the composition.

[0153] The ingredients used are as follows: - PAG = triblock block copolymer successively comprising propylene oxide, ethylene oxide and propylene oxide units, having a molecular mass ranging from 1100 to 3000 g / mol; - PEA = polyether diamine comprising only propylene oxide units and having a molecular mass ranging from 1000 to 3000 g / mol; - pH regulator = amine; - additives = additives conventionally used in fluids intended for metalworking, including in particular an anti-corrosion agent, an anti-oxidant, an emulsifier.

[0154] [Tables 1] CCI Cil PAG 20% 20% PEA - 4% pH regulator 25% 25% water 37.12% 33.12% additives 17.88% 17.88%

[0155] The CCI and Cil lubricating compositions are tested and compared.

[0156] The objective of this test is to measure the torque obtained by drilling 7 consecutive holes on an aluminum material, using a Microtap testing machine. The test is implemented in section. When drilling, a speed of 600 rpm is used to drill a pre-hole with a depth of 6 mm, with a screw pitch between 2 and 5 mm.

[0157] The results are expressed as a percentage gain compared to a lubricating composition marketed for machining aluminum (called “reference”).

[0158] The test is carried out at room temperature.

[0159] For this test, the lubricating compositions described in Table 1 are diluted to 10% in water.

[0160] A drop of lubricating composition to be tested is introduced into each hole, the hole is filled 100% with the lubricating composition, avoiding air bubbles.

[0161] The protocol is as follows: - the torque exerted by the spindle integrating the drill is measured for each hole, an average of the power generated is calculated; - the torque as a function of time per hole is recorded; - the temperature before / after each hole is measured; an average is calculated; - the relative torque and temperature increase of the tested composition is calculated relative to the reference.

[0162] The results are shown in Table 2. The result (the couple) is expressed as a percentage relative to the reference composition.

[0163] [Tables2] CCI Cil % gain -1.3% -6.9%

[0164] The results in Table 2 show that the lubricating composition according to the invention Cil generates significantly less power for the lubrication of the aluminum part. The lubricating composition according to the invention therefore has better properties than the comparative CCI composition.

[0165] Example 2: Tests measuring the service life on steel

[0166] In this example, composition Cil (see Table 1) is compared to a commercial composition comprising an oil-in-water emulsion containing neither PAG nor PEA (CC2) marketed for steelworking.

[0167] For this test, the composition Cil described in Table 1 is diluted to 8%.

[0168] The test protocol is as follows:

[0169] The machine is a semi-industrial machine tool. The steel tool is used to make 460 holes, successively, on a steel plate under the following conditions: - spindle rotation speed N = 6478 rpm - cutting speed Vc = 203 m / min - feed rate per revolution F = 0.3 mm / hole - drilling depth 42 mm - diameter 10 mm

[0170] The diameter of the holes is measured, as well as the power required to make the holes.

[0171] The power drift during machining is determined, as well as the diameter drift (also called metrological drift). The greater the drift, the shorter the life of the lubricating composition.

[0172] The results are presented in Table 3.

[0173] [Tables3] CC2 Cil Power drift 39% 25% Diameter drift 20 pm 12 pm

[0174] The results in Table 3 show that the lubricating composition according to the invention has a better service life than the commercial composition of the state of the art, and this during the machining of steel parts.

[0175] Example 3: Tests measuring lubricating properties (coefficient of friction)

[0176] The lubricating compositions tested are detailed in Table 4. The percentages are expressed as percentages by weight relative to the total weight of the composition.

[0177] The ingredients used are as follows: - PAG = triblock block copolymer successively comprising propylene oxide, ethylene oxide and propylene oxide units, having a molecular mass ranging from 1100 to 3000 g / mol; - PEA = polyether diamine comprising only propylene oxide units and having a molecular mass ranging from 1000 to 3000 g / mol; - pH regulator = amine; - additives = additives conventionally used in fluids intended for metalworking, including in particular an anti-corrosion and an anti-oxidant.

[0178] [Tables4] CC3 CI2 PAG - 20% PEA 20% 4% pH regulator 25% 25% water 37% 41% additives 14% 14%

[0179] For this test, the compositions described in Table 4 are diluted to 10% in water.

[0180] The objective of this test is to measure the extreme pressure properties of the compositions. The CC3 and CI2 lubricating compositions are tested and compared, using a 4-ball test according to ASTM D2783, adapted with the following parameters:

[0181] - speed close to 1500 rpm,

[0182] - room temperature, i.e. approximately 20°C,

[0183] - 1 minute load duration for welding load measurement or 10 seconds for measuring the last load before seizure,

[0184] - initial contact pressure of approximately 3.5 GPa.

[0185] The extreme pressure measurement is carried out by rotating a stainless steel ball on three stainless steel balls held stationary, the 4 balls being entirely covered with a film of lubricant. A load is applied to the balls and gradually increased (by 10 kg) until the balls weld together. The balls are changed before each increase in load.

[0186] The extreme pressure power corresponds to the value of the load from which the 4 balls weld, preventing the rotation of the upper ball on the other 3. The greater the load, the higher the extreme pressure power.

[0187] The results are shown in Table 5. For this test, the tests were carried out under the conditions of dilution of the lubricating composition on the machine, namely at a dilution of between 8 and 10%.

[0188] [Tables5] CC3 CI2 Welding load (kilogram force) 120 140

[0189] The results in Table 5 show that the lubricating composition according to the invention CI2 makes it possible to have better extreme pressure properties than the comparative lubricating composition CC3.

[0190] The lubricity of the CC3 and CI2 compositions is also evaluated and compared using a Plint SRV test.

[0191] The Plint SRV type test is carried out according to the publication JSAE 9436260 (Frictional Characteristics of Organomolybdenum Compound with Addition of Sulfurized Additives Takashi Kikuchi, Yoko Yonekura, Kenyu Akiyama (Toyota Motor Corporation), pp. 105-108, 13) with the following characteristics:

[0192] - stroke: 2.2 mm,

[0193] - frequency: 30 Hz (0.13 m / s),

[0194] - load: 150 N,

[0195] - temperatures (°C): 40, 50, 60, 70.

[0196] The results are shown in Table 6. For this test, the tests were carried out under the conditions of dilution of the lubricating composition on the machine, namely at a dilution of between 8 and 10%.

[0197] [Tableauxô] Coefficient of friction CC3 CI2 40°C 0.13 0.12 50°C 0.14 0.12 60°C 0.15 0.11 70°C 0.16 0.11

[0198] The results in Table 6 show that the lubricating composition according to the invention CI2 makes it possible to have better lubricating properties than the comparative composition CC3, since the coefficients of friction are lower, in particular at high temperature.

[0199] In summary of the above examples, the lubricating composition according to the invention comprising the combination of a PAG and a PEA makes it possible to obtain excellent properties, both for machining aluminum and for machining steel, with excellent service life, reduced generated power and very good extreme-pressure properties.

Claims

Claims

1. Lubricating composition comprising water and: - from 1 to 60% by weight of poly(alkylene glycol), - from 0.5 to 30% by weight of polyetheramine, relative to the total weight of the lubricating composition, in which the poly(alkylene glycol) is(are) chosen from block copolymers comprising ethylene oxide units and propylene oxide units, and mixtures thereof.

2. Lubricating composition according to claim 1, comprising water and: - from 5 to 50% by weight of poly(alkylene glycol), - from 1 to 20% by weight of polyetheramine chosen from monoamines, diamines and triamines comprising units chosen from alkylene oxides comprising from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, relative to the total weight of the lubricating composition, in which the poly(alkylene glycol) is(are) chosen from block copolymers comprising ethylene oxide units and propylene oxide units, and mixtures thereof.

3. A lubricating composition according to claim 1 or 2, further comprising at least one additive selected from alkali bases, alkanolamines and mixtures thereof, the alkanolamines preferably being selected 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, and the alkali bases preferably being selected from potassium hydroxide and sodium hydroxide.

4. Lubricating composition according to any one of claims 1 to 3, in which the poly(alkylene glycol) is(are) chosen 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.

5. A lubricating composition according to any one of claims 1 to 5. 4, wherein each poly(alkylene glycol) has a molecular weight ranging from 500 to 10000 g / mol, preferably from 800 to 5000 g / mol, more preferably from 1100 to 3000 g / mol.

6. A lubricating composition according to any one of claims 1 to 5, wherein each poly(alkylene 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.

7. Lubricating composition according to any one of claims 1 to 6, in which the polyetheramine(s) are chosen from monoamines comprising ethylene oxide units and / or propylene oxide units, diamines comprising ethylene oxide units and / or propylene oxide units, and mixtures thereof, preferably from diamines comprising ethylene oxide units and / or propylene oxide units.

8. A lubricating composition according to any one of claims 1 to 7, wherein each polyetheramine has a molecular weight ranging from 500 to 5000 g / mol, preferably from 1000 to 3000 g / mol.

9. Use of the lubricating composition according to any one of claims 1 to 8, as a fluid for working metals, the metals preferably being chosen from steel and aluminum.

10. Use according to claim 9, wherein the composition is used for machining metals and / or for forming and / or for cutting and / or for stamping and / or for rolling metals.

11. Use of 0.5 to 30% by weight of polyetheramines in a lubricating composition comprising water and 1 to 60% by weight of poly(alkylene glycol), relative to the total weight of the lubricating composition, for improving the lubricating properties during metalworking using said lubricating composition, in which the poly(alkylene glycol) is(are) chosen from block copolymers comprising ethylene oxide units and propylene oxide units, and mixtures thereof.

12. Use according to claim 11, wherein the lubricating composition is as defined in any one of claims 1-2

13. a o. Use according to claim 11 or 12, for improving the lubricating properties of the lubricating composition during machining and / or during forming and / or during cutting, and / or during stamping and / or during rolling of metals. 21