FR2913356A1 - LUBRICATION WITH DISPERSIONS IN METAL DEFORMATION PROCESSES - Google Patents

Abstract

The subject of the present invention is the use, as a lubricating composition in a metal shaping process, with the exception of the shaping of steel wires intended to reinforce a pneumatic tire, a dispersion of solid particles. The present invention also relates to a metal deformation process where the dispersion is implemented. The present invention also relates to suitable dispersions and / or concentrated lubricating formulations adapted.

Description

Lubrication by dispersions in deformation processes of

metals

  The subject of the present invention is the use, as a lubricating composition in a metal shaping process, with the exception of the shaping of steel wires intended to reinforce a pneumatic tire, a dispersion of solid particles. The present invention also relates to a metal deformation process where the dispersion is implemented. The present invention also relates to suitable dispersions and / or concentrated lubricating formulations adapted.

  Metal shaping processes, such as cutting, drawing, rolling or drawing processes, often require the use of lubricants, in particular to reduce tool wear, possibly to remove heat. generated by deformation, and / or to increase productivity. Among the metal deformation processes, dry processes are known where a lubricant in pasty form is applied to the deformation tool or to the metal to be deformed. Wet processes are also known where the metal to be deformed as well as the deformation tools are in contact with a liquid lubricating composition, for example in a bath of lubricating composition. Among the liquid lubricating compositions, there are known compositions such as whole oils based on an oily liquid vector. Aqueous compositions are also known. Among the aqueous compositions, liquid phase (s) compositions are known comprising an aqueous vector and lubricating compounds present in the composition in non-solid forms, for example in the form of emulsions, micelles, or arrangements of amphiphilic compounds in the form of vesicles or lamellar crystallites. Compositions in the form of solid particle dispersions of waxes based on Ethylene Bis-Stearamide (EBS) are also known. WO 01/29159, Rhodia, describes the use of lamellar crystallites in liquid phase lubricant compositions for the deformation of metals, particularly in wet drawing processes. WO 02/062931, Rhodia, discloses the use for the cold rolling of metals of an aqueous composition comprising a dispersion of EBS particles, a carboxylic acid and a phosphate ester. FR 2130981, Rhone-Poulenc, discloses liquid phase aqueous lubricant compositions comprising an amide phosphate. The document FR 1037447, Bataafsche Petroleum Maatschappij, describes aqueous compositions known as an emulsion comprising paraffin with a melting point of greater than 71 ° C., and at least one liposoluble compound known as an emulsifier, such as Ethylene Glycol Monostearate (EGMS), sorbitan esters, or ethoxylated castor oil. The compositions are said to be suitable for metal deformation processes, in particular for stretching steel strips.

  US 4612,27, Hitachi, discloses whole oil type lubricating formulations comprising phosphorus compounds for metal working. US 3966619, Alcan, discloses lubricants for the deformation of aluminum. Lubricants are aqueous compositions comprising an alkylamine and an ethoxylated phosphate ester.

  US 4481038, Glyco, discloses concentrated formulations for drawing or rolling metals, based on an EBS wax dispersion. US 4812248 and EP 227360, Alcan, disclose lubricating compositions for aluminum drawing, comprising a non-aqueous volatile liquid carrier, such as xylene, and Ethylene Glycol Di-Stearate (EGDS) or Ethylene Glycol Mono Stearate (EGMS). Such compositions are not advantageous because they use volatile organic compounds whose use is subject to quotas, or even prohibited. There is a need for other compositions. EGDS is a known compound, used in crystallized form as a beading and / or viscosizing agent in cosmetic formulations, or used as a bulk additive in thermoplastics, as a lubricant to accelerate molding rates. US 2126128, Montgomery, discloses lubricating compositions for the deformation of metals, applied hot and forming a film on the surface to be deformed. The compositions comprise stearic acid and a mineral oil. These are compositions of whole oils type or even whole wax type. US 6329329, Alcan, teaches applying to a metal a molten lubricant, without a liquid carrier, comprising stearic acid, Ethylene Glycol Di-Laurate (EGDL, laurate is a C12 group). and Ethylene Glycol Mono laurate (EGML).

  US 2948681, Standart Oil, discloses a method of drawing metal wires using an entire oil type lubricating composition including a mineral oil, glycerol monolaurate, and ethylene glycol butyl ether. US 3526596, Quaker Chemical, describes the working of metals at a very high temperature where they are malleable, with the aid of esters in molten form, without water (it would in any case be evaporated).

  US 4191658, Lubrizol, discloses a metal drawing process in which a molten lubricant composition is applied to the metal, which solidifies upon cooling to form a film. The compositions are nonaqueous, and include a phosphate ester. and esters of fatty acids, for example the diester of adipic acid and a C16-C18 fatty acid. US 4578202, Merck, discloses oils for cutting metals. These are whole oil type compositions without water. EP 192329, Alcan, describes a metal deformation process in which a composition comprising solid particles of a wax (EBS in the examples) of a water size of less than 1 μm, dispersed in a vector of type, is applied. nonaqueous volatile solvent, such as xylene. The composition forms a film on the metal. Such compositions are not advantageous because they use volatile organic compounds whose use is subject to quotas, or even prohibited. There is a need for other compositions.

  US 2039111, Texas Company discloses engine lubrication without deformation of the metal using oils comprising EGDS. US 4175047, Mobil OR, discloses engine lubrication without deformation of the metal using oils comprising certain esters. The use of aqueous lubrication compositions in metal deformation processes can be particularly advantageous: such formulations are easy to use, low pollution, economical, and can allow to evacuate the heat produced during the deformation is desirable. The drawing of steel wires through dies is often carried out under extremely severe conditions of temperature and pressure because of the significant friction that develops between the wire and the dies. This results in rapid wear of the surface of the die as that of the wire, the risk of breakage and appearance of superficial defects of the wire. A too rapid increase of the diameter of the die and thus of the drawn wire can be unacceptable from the industrial point of view. To overcome the above problems, at least minimize them, it is known to use lubricants of the oily or aqueous type. In the most extreme conditions, aqueous lubricants are generally preferred because of their superior cooling capacity of the metal. They have other benefits of being easy to use, low pollution and more economical. Compositions comprising particles of EBS dispersed in water are quite common and allow to obtain some lubrication. However, there is a need for more efficient lubrication in metal deformation processes.

  The invention responds to this need by proposing the use, as a lubricating composition in a metal shaping process, with the exception of the shaping of steel wires intended to reinforce a bandage. pneumatics, a dispersion in an aqueous liquid carrier of solid particles, at 23 C, preferably at least a temperature range of 23 C to 40 C, a compound B ester of a C14-C22 fatty acid , preferably C16-C22 with a diol or a polyol, of formula (I) below: [R-COO-] X A - [- OH] y (I) where: - R is an alkyl group, saturated or unsaturated , linear or branched, C13-C21, preferably C15-C21, A is a hydrocarbon group, optionally interrupted by one or more heteroatoms, of valence x + y, - x is an average number between 1 and 5, - y is an average number between 0 and 5, - x + y is an average number of between 1 and 10, preferably between 2 and 5.

  The invention also relates to lubricating compositions suitable for use above or others. The invention also relates to concentrated lubrication formulations suitable for use above or others. The invention also relates to processes for preparing the concentrated formulations and / or lubricating compositions. The invention also relates to the process for shaping metals using the lubricant composition.

  In particular, the invention makes it possible to obtain a more efficient lubrication. "More efficient" lubrication can notably result in: - greater productivity, for example greater production speed, and / or - a lower frequency of replacement of the shaping tools, and / or - by less breakage of metals during shaping, and / or - by the possibility of shaping harder metals under production conditions similar to those used for forming less hard metals. Effective lubrication can also be characterized by a low coefficient of friction, for example by a low coefficient of friction determined by tribology techniques, especially in a type of contact EHD ("Dynamic Elasto Hydro"). Effective lubrication can also be characterized by low wear, for example determined by material balances carried out in tribology studies, especially in a contact type EHD, or Falex type. The compositions, dispersions and formulations of the invention can moreover be particularly simple and / or of flexible use (easily adaptable, "versatile" in English). The compositions, dispersions and formulations of the invention can also make it possible to obtain an excellent constancy of the performance by limiting the possible interactions with the surface of the metal and its possible coating, and thus the evolution of the chemical composition of composition baths. lubricant during its use (so-called "bath break-in" problem). This is an advantage over lubricating compositions of the emulsion type.

  Lubricating Composition The lubricating composition comprises: an aqueous liquid carrier, solid particles dispersed in the aqueous liquid carrier, and optionally other compounds. The liquid vector is an aqueous vector. This will usually be water only. However, it is conceivable to combine minor amounts (less than 10% by weight, or even less than 1% by weight) of solvents, preferably of low volatility or non-volatility. The solid particles are particles based on a B compound detailed below. The particles are solid at 23 ° C., preferably at a temperature range, ranging from 23 ° C. to 40 ° C., preferably from 23 ° C. to 50 ° C. They may have a melting point of less than 200 ° C., preferably less than 135 ° C. The melting point may be less than 70 ° C. The particles may in particular have a melting point of greater than or equal to 60 ° C. Compound B may be chosen as a function of the melting point. The melting point is generally higher than the temperature at which the process is carried out. It is not excluded, however, that the temperature exceeds this melting point very locally, in a manner that is difficult to measure. Such a phenomenon does not affect the invention. The particles preferably have a particle size distribution with at least 90% by weight of particles of size between 0.1 and 50 μm. The particle size distribution may for example be determined using a light scattering granulometer, or laser like a HORIBA LA 910 type of apparatus. The particle size may especially be fine (of average size by weight between 0.degree. 5 and 10 μm) or coarser (average size by weight between 10 and 50 μm). It is not excluded that the particle size distribution is bi-populated, with a fine population, and a coarser population. The particles may in particular have a particle size distribution: with more than 50% by weight of particles having a size of between 0.5 and 10 μm, or with more than 50% by weight of particles having a size of between 10 and 30 μm, preferably between 10 and 20 pm. A very coarse particle size may in particular be difficult to stabilize. A very fine grain size can be binding. Solid particles may not be in pearl crystalline form. Crystallization is not necessary for the present invention. The presence of crystals can be evaluated by observation with Scanning Electron Microscopy of more or less organized platelets in aggregates. In addition, if a method for obtaining the particles by hot emulsion followed by cooling is used, it is not necessary to observe a temperature crystallization ramp.

  Compound B The particles are based on a compound B. By "based on a compound B" is meant that more than 50% by weight, preferably more than 75%, preferably more than 90%, or even 100%, by weight of the particles consists of a compound or a mixture of compounds responding to the definition of compound B given below. Compound B is an ester of a C16-C22 fatty acid, preferably a C16-C22 fatty acid, with a diol or a polyol, of formula (I) below: [R-COO-] X A - [- OH] y (I) wherein: - R is a linear or branched, C 13 -C 21, preferably C 15 -C 21, saturated or unsaturated alkyl group; -A is a hydrocarbon group, optionally interrupted by one or more heteroatoms, of valence; x + y, - x is an average number between 1 and 5, - y is an average number between 0 and 5, - x + y is an average number between 1 and 10, preferably between 2 and 5. In the present application, an average number may designate an integer or a decimal number. In the present application, the expression "between X and Y" includes the terminals X and Y.

  If y is different from 0, it means that it is a partial ester. If y = 0, it means that it is a completely esterified compound. For example, if x + y = 2, y = 0 and x = 2, it is a diester (totally esterified).

  Group A is a group whose compound of formula A - (- OH), + y is a diol or a polyol. It may especially be a diol such as ethylene glycol, or a polyol such as glycerol. Advantageously: - A is a divalent group (x + y = 2; A - (- OH) X + y is a diol), and - y = 0. The group A can in particular have the following formula: - (CH 2) Z [OE] n- [OP] m- (CH 2) Z where: - z, identical or different, is an integer from 1 to 10, - OE is an optional ethylene oxide group, and n is an average number inclusive between 0 and 100, preferably from 0 to 10, and - OP is an optional propylene oxide group, and m is an average number of between 0 and 100, preferably 0 to 10.

  If EO and / or OP groups are present, the compound of formula A - (- OH) 2 may be a product of (poly) ethoxylation and / or (poly) propoxylation, or condensation of ethylene glycol and / or propylene glycol. Group A preferably does not comprise EO and / or OP groups, and it is a C 1 -C 10, preferably C 2 -C 4, alkylene group. The group A can in particular be a methylene, ethylene, propylene or butylene group or a mixture of these groups. The group R is a linear or branched, saturated or unsaturated, C13-C21, preferably C15-C21, alkyl group. It is an alkyl group corresponding to a fatty acid of formula R-000H, C14-C22, preferably C16-C22. These fatty acids and alkyl groups are known. These are generally derived from vegetable oils. They can be present in mixtures. In the case of mixtures, the definition of all the groups, irrespective of the number of carbon atoms, if the group (or the corresponding acid) predominates in weight (relative majority, preferably absolute preferably at least 75%) corresponds to the definition. It is common to reduce the denomination to the group (or corresponding acid) to the group (or acid) rajoritary. The group R may especially correspond to fatty acid C14 or C16 or C18 or C22, such as myristic, palmitic, stearic, oleic, erucic or behenic acids. Preferably the group R-COO- is a C18 fatty acid, preferably stearic acid. The use of a compound B based on Ethylene Glycol Di-Stearate (EGDS) is particularly interesting. By compound "based on ethylene glycol distearate" is meant a compound or a composition comprising at least 75% by weight of ethylene glycol distearate, and optionally other compounds, in particular ethylene glycol monostearate (EGMS). . Unless otherwise specified or more precise in particular as regards the presence of other compounds, the term distearate of ethylene glycol or the acronym EGDS will denote a compound based on ethylene glycol distearate.

  The dispersion of the invention advantageously comprises from 0.05 to 6% by weight of the particles, preferably from 0.2 to 3% by weight. Concentrations of 0.5 to 1.5% by weight are quite suitable for effective lubrication.

  Amphiphilic Compound C The dispersion advantageously comprises, in addition to particles, at least one amphiphilic compound C. Such a compound may contribute to stabilizing the solid particles (preventing, for example, decantation which would affect the efficiency or require additional stirring means and may interfere with the formatting process). It can also help optimize lubrication efficiency. The amphiphilic compound C is preferably water-soluble. By water-soluble is meant compounds soluble in aqueous medium, at 23 C, at a concentration of 1% by weight.

  Compound C can in particular be a surfactant, but it is not excluded to use more complex compounds such as polymers with different blocks of alkylene oxide block copolymers (the latter are conventionally classified as surfactants) or comb copolymers. The surfactants are generally amphiphilic compounds of relatively low molecular weight (for example less than 1000 g / mol) and / or polyalkoxylates (such as alkylene oxide block copolymers).

  According to a particular embodiment, the amphiphilic compound C is a nonionic amphiphilic compound. The amphiphilic compound C can in particular be an anionic, cationic, amphoteric, zwitterionic or nonionic surfactant or a mixture of such surfactants. The use of nonionic surfactants is particularly effective.

  By way of examples of anionic surfactants, mention may be made, without intending to be limited thereto: alkylsulphonic acids, arylsulphonic acids, optionally substituted with one or more hydrocarbon groups, and whose acid function is partially or totally salified, such as C 8 -C 50, more particularly C 8 -C 30, preferably C 10 -C 22, alkylsulphonic acids, benzenesulphonic acids, naphthalenesulphonic acids, substituted with one to three C 1 -C 30, preferably C 4 -C 16, alkyl groups, and / or C2-C30 alkenyls, preferably C4-C16 alkenyls. the mono- or diesters of alkylsulfosuccinic acids, of which the linear or branched alkyl part, optionally substituted with one or more hydroxylated and / or alkoxylated, linear or branched C2-C4 (preferably ethoxylated, propoxylated, ethopropoxylated) groups. the phosphate esters chosen more particularly from those comprising at least one saturated, unsaturated or aromatic hydrocarbon group, linear or branched, comprising 8 to 40 carbon atoms, preferably 10 to 30, optionally substituted with at least one alkoxylated group (for example ethoxylated, propoxylated, ethopropoxylated). In addition, they comprise at least one phosphate ester group, mono- or di-esterified so that one or two acid groups can be free or partially or totally salified. The preferred phosphate esters are of the mono- and diester type of phosphoric acid and of alkoxylated (ethoxylated and / or propoxylated) mono-, di- or tristyrylphenol, or of alkoxylated (ethoxylated) mono-, di- or trialkylphenol and / or propoxylated), optionally substituted with one to four alkyl groups; phosphoric acid and a C8-C30 alcohol, preferably C10-C22 alkoxylated (ethoxylated or ethopropoxylated); phosphoric acid and an alcohol C8-C22, preferably C10-C22, non-alkoxylated. sulphate esters obtained from saturated or aromatic alcohols, optionally substituted with one or more alkoxylated groups (ethoxylated, propoxylated, ethopropoxylated), and for which the sulphate functional groups are in the free acid form, or partially or completely neutralized . By way of example, mention may be made of sulfate esters obtained more particularly from saturated or unsaturated C 8 -C 20 alcohols, which may comprise 1 to 8 alkoxylated units (ethoxylated, propoxylated, ethopropoxylated); sulphate esters obtained from polyalkoxylated phenol, substituted with 1 to 3 saturated or unsaturated C 2 -C 30 hydroxycarbon groups, and in which the number of alkoxylated units is between 2 and 40; sulfate esters obtained from polyalkoxylated mono-, di- or tristyrylphenol in which the number of alkoxylated units ranges from 2 to 40.

  The anionic surfactants can be in acid form (they are potentially anionic), or in partially or totally salified form, with a counterion. The counterion may be an alkali metal, such as sodium or potassium, an alkaline earth metal, such as calcium, or an ammonium ion of formula N (R) 4+ in which R, identical or different, represent a hydrogen atom or a C1-C4 alkyl radical optionally substituted by an oxygen atom. By way of examples of nonionic surfactants, mention may be made, without intention of being limited thereto: polyalkoxylated phenols (ethoxylated, propoxylated, ethopropoxylated) substituted with at least one C 4 -C 20, preferably C 4 -C 20, alkyl radical C12, or substituted by at least one alkylaryl radical whose alkyl part is C1-C6. More particularly, the total number of alkoxylated units is between 2 and 100. By way of example, mention may be made of polyalkoxylated mono-, di- or tri (phenylethyl) phenols, or polyalkoxylated nonylphenols. Among the ethoxylated and / or propoxylated di- or tristyrylphenols, mention may be made of ethoxylated di- (1-phenylethyl) phenol, containing 10 oxyethylenated units, ethoxylated di- (1-phenylethyl) phenol, containing 7 oxyethylenated units, sulfated ethoxylated di- (1-phenylethyl) phenol, containing 7 oxyethylene units, ethoxylated tri- (1-phenylethyl) phenol, containing 8 oxyethylenated units, ethoxylated tri- (1-phenylethyl) phenol containing 16 units oxyethylenes, sulfated ethoxylated tri- (1-phenylethyl) phenol, containing 16 oxyethylenated units, ethoxylated tri- (1-phenylethyl) phenol, containing 20 oxyethylene units, ethoxylated tri- (1-phenylethyl) phenol, posphated, containing 16 oxyethylenated units. alcohols or C6-C22 fatty acids, optionally polyalkoxylated (ethoxylated, propoxylated, ethopropoxylated). In the case where they are present, the number of alkoxylated units is between 1 and 60. polyalkoxylated triglycerides (ethoxylated, propoxylated, ethopropoxylated) of vegetable or animal origin. Thus triglycerides from lard, tallow, peanut oil, butter oil, cottonseed oil, linseed oil, olive oil, are suitable. palm oil, grape seed oil, fish oil, soybean oil, castor oil, rapeseed oil, coconut oil coconut oil, and comprising a total number of alkoxylated units of between 1 and 60. The term ethoxylated triglyceride is intended both for the products obtained by ethoxylation of a triglyceride by ethylene oxide and those obtained by ethoxylation of a triglyceride with ethylene oxide. by trans-esterification of a triglyceride with a polyethylene glycol. polyalkoxylated sorbitan esters (for example ethoxylated, propoxylated, ethopropoxylated). block copolymers of ethylene oxide and C3-C10 alkylene oxide. fatty amines, especially C6-C22, optionally polyalkoxylated (for example ethoxylated, propoxylated, ethopropoxylated). In the case where they are present, the number of alkoxylated units may be between 1 and 60.

  As examples of zwitterionic or amphoteric surfactants, mention may be made, without intending to be limited thereto: betaines, especially alkyldimethylbetaines, and alkylamidoalkylbetaines, such as alkylamidopropyldimethylbetaines, amine oxides, especially alkyldilmethylamine oxides, and alkylamidoalkylamine oxides such as alkylamidopropyldimethylamine oxides - sultaines - imidazoline derivatives, - amphopropionates.

  As examples of cationic surfactants, mention may be made, without intending to be limited to: quaternary fatty amines, optionally polyalkoxylated.

  May especially enter into the composition, alone or in mixtures or combinations: - Nonionic surfactants of the fatty acid type or polyalkoxylated fatty acids (for example ethoxylated, propoxylated or ethopropoxylated) (family of Alkamuls RHODIA, as examples oils ethoxylated hydrocarbons: Alkamuls OR 36, RC Alkamuls, Alkamuls R81, Alkamuls 696), ethoxylated alcoholic or propoxylated ethoxylated nonionic surfactants, polyalkyleneglycol, such as the Rhodasurf family of RHODIA, for example the Rhodasurf LA / 30, Rhodasurf ID5, Rhodasurf 860P), ethoxylated aromatic or ethoxylated propoxylated nonionic surfactants, for example the Rhodia Igepal family, surfactants of the ethoxylated or propoxylated ethoxy block copolymer type, for example the RHODIA Antarox family, such as Antarox B848, Antarox PLG 254, Antarox PL 122, Antarox SC138, -. Anionic surfactants, such as sulphonates, aliphatic sulphonates, sulphonates carrying ester or amide groups such as isothionate (sulphoester), taurates (sulphoamides), sulphosuccinates, sulphosuccinamates, or even sulphonates which do not carry amide or ester groups such as alkyldiphenyoxide disulphonate, alkyl naphthalene sulphonate, naphthalene / formaldehyde sulphonates with, for example, Dodecyl benzenesulphonate (RHODIA Rhodacal family, such as for example (Rhodacal 60 BE), phosphate esters, for example the Rhodafac family from RHODIA as Rhodafac PA 17, Rhodafac MB, Styrylphenol-based compounds such as Distyrylphenol, Tristyrylphenol, which may be ethoxylated or ethoxylated propoxylated, phosphated, sulphated, for example the Soprophor family of RHODIA such as Soprophor DSS7, Soprophor BSU, Soprophor 3D33, Soprophor 4D384, Soprophor 796P, - surfactants derived from terp nes for example the family of RHODOCLEAN from Rhodia - The ethoxylated fatty amines, for example the family of Rhodia Rhodameen.

  Advantageously, the amphiphilic compound C is chosen from the following surfactants: (1) ethoxylated and / or propoxylated ethylene oxide and ethylene oxide block copolymers C3-C, o, c2) di- or tristyrylphenols, and c3) fatty amines, optionally polyalkoxylated. It may be in particular a block copolymer of ethylene oxide and propylene oxide, preferably of structure [OE] n '- [OP], - [OE],., Where: - EO is an ethylene oxide group, and n ', which is the same or different, is an average number of between 2 and 1000, and - OP is an optional propylene oxide group, and m' is an average number of between 2 and 1000. .

  The ratio by weight between the groups OE and OP may especially be between 90/10 and 10/90, for example between 70/30 and 40/60. The total number of units OE and OP can in particular be between 20 and 500, for example between 50 and 200. It is possible in particular to use the surfactant Antarox SC138 marketed by Rhodia.

  The mass ratio between the amphiphilic compound C and the particles may especially be between 1/100 and 10/100, preferably between 2.5 / 97.5 and 7.5 / 92.5. Thus, typically, the aqueous dispersion can comprise from 0.01% to 0.6%, preferably from 0.02% to 0.3%, for example from 0.05% to 0.25%, by weight, of amphiphilic compound C. It is noted that such proportions are very different from those used in foaming detergent formulations such as shampoos, or shower gel, which do not correspond to the lubricating composition of the invention. They are also very different from those used for additives of concentrated ingredient type beadless fluid to be used for the preparation of cosmetic compositions especially cold (additives "cold pearl" in English).

  Extreme additive pressure D The dispersion may advantageously comprise, in addition to the particles, at least one extreme pressure additive D. Such additives may in particular further improve the lubrication under the most severe temperature conditions and preserve a lubricating film between the metal and the metal. formatting tool. This additive may be used, in addition to or instead of the amphiphilic compound C. It is mentioned that the extreme pressure additive may be amphiphilic or not. If it is an amphiphilic additive, it may act as an amphiphilic compound C. If the lubricating composition comprises an amphiphilic compound C, it may additionally contain the extreme pressure additive D, which is different from the amphiphilic compound C, the additive being itself amphiphilic or not. For example, the composition may comprise a combination of an amphiphilic compound C which is not phosphorus-based and / or which is not suffering, with an extreme phosphorous or sulfur-containing amphiphilic pressure additive D. The extreme pressure additive can in particular be an extreme pressure additive based on sulfur and / or phosphorus, preferably chosen from: - phosphate esters, optionally polyalkoxylated, - phosphonates, - sulphates, - sulphides and polysulphides, and - their mixtures.

  The phosphate ester may in particular be a compound of formula (R'O) X, -P (= O) (OH) X ,,, where R 'is an optionally polyalkoxylated hydrocarbon group, x' and x "being equal at 1 or 2, with the proviso that the sum of x 'and x "is equal to 3. The group R' may in particular be an alkyl, alkylaryl, polyalkylaryl or (polyarylalkyl) aryl group (the alkyl groups may be linear or branched saturated or unsaturated), C 1 -C 35, preferably C 5 -C 30 (not counting the number of carbon atoms of the possible polyalkoxylates). The polyalkoxylated compounds may be polyethoxylated compounds. The degree of alkoxylation may especially be between 1 and 80; preferably between 1 and 15. Preferably, the acidic phosphate ester corresponds to the following formula: ## STR2 ## wherein R " identical or not, represents a hydrocarbon radical comprising 1 to 30 carbon atoms, A "identical or not represents a linear or branched alkylene radical having 2 to 4 carbon atoms, y ', which is a mean value, is between 0 and 100, and x 'and x "are equal to 1 or 2, provided that x' + x" = 3.

  More particularly, R "or R 'is a hydrocarbon radical containing 1 to 30 carbon atoms, aliphatic, cycloaliphatic, saturated or unsaturated, or aromatic, preferably the radicals R" or R', which are identical or different, are alkyl radicals. or alkenyls bearing one or more linear or branched ethylenic unsaturations containing 8 to 26 carbon atoms. By way of examples of such radicals, mention may be made especially of stearyl, oleyl, linoleyl and linolenyl radicals. In addition, the radicals R "or R ', which may be identical or different, may be aromatic radicals bearing alkyl, arylalkyl or alkylaryl substituents, these radicals comprising 6 to 30 carbon atoms. mention may be made, inter alia, of nonylphenyl, mono-, di- and tri-styrylphenyl radicals.More particularly, the (OA -) groups, which may be identical or different, correspond to an oxyethylenated, oxypropylenated, oxybutylenated radical or mixtures thereof. Preferably, said group corresponds to an oxyethylenated and / or oxypropylenated radical. As for the value of y ', average, it is preferably between 0 and 80. Useful extreme pressure additives are in particular marketed by Rhodia under the names Lubrhophos and Rhodafac. It is mentioned that the extreme pressure additives are preferably present in the formulation in salt form, neutralized. The neutralization can be obtained using any organic or mineral base. It is possible in particular to use organic amines, for example optionally polyalkoxylated fatty amines. We give more details below. The dispersion may comprise from 0.01% to 5% by weight of the extreme pressure additive, preferably from 0.1% to 2%.

  Other compounds As mentioned above the lubricating composition may comprise at least one base. The base is preferably water soluble. Thus, by way of nonlimiting examples of such compounds, there may be mentioned hydroxides, hydroxycarbonates, carbonates, bicarbonates, alkali metal, ammonia.

  Preferably, the bases employed are organic bases which are more particularly chosen from primary, secondary or tertiary amines or polyamines, comprising at least one hydrocarbon radical having 1 to 40 carbon atoms, linear, branched or cyclic, optionally substituted by a or more hydroxyl radicals, and / or one or more alkoxylated groups. Said alkoxylated groups are preferably ethoxylated units. In addition, the number of alkoxylated units, if present, is less than or equal to 100.

  According to a preferred embodiment of the invention, when the amines have at least two amine functional groups, said functions are separated two by two by a number of carbon atoms from 2 to 5. As suitable amines, it is possible to mention monoethanolamine, diethanolamine, ethylenediamine, aminoethylethanolamine, aminomethylpropanolamine. The polyalkoxylated fatty amines can also be used as organic bases, for example those marketed by Rhodia Chimie under the name Rhodameen CS20. The lubricating composition may in particular comprise other particles, whether solid or non-solid. In such a case, the particles based on the compound B may preferably constitute more than 50%, more preferably more than 75%, for example more than 90% of the solid particles of wax forming the lubricating base of the lubricant composition of the invention and / or a concentrated formulation. It is preferred, however, that the solid particles based on compound B constitute all the solid particles of wax forming the lubricating base.

  The composition may comprise other compounds often commonly present in aqueous lubricating compositions. It may for example be antifoam additives, anti-corrosion additive, anti-scale additives, preservatives, pH modifiers, buffers, etc ...

  Preparation of the lubricating composition and concentrated formulation The lubricating composition can be prepared by simple mixing of its constituents.

  It is noted that the lubricating composition can be obtained by diluting a concentrated formulation in water. The dilution may for example be from 0.5 to 18 parts, preferably from 1 to 6 or 10 parts of concentrated formulation per 100 parts of water. The concentrated formulation comprises: - the aqueous liquid vector -. solid particles, -. optionally the amphiphilic compound C, and -. optionally the extreme pressure additive D, - • possibly other compounds.

  Details of these different compounds have been given above; they can be considered with respect to the concentrated formulation, and are not repeated here.

  The proportion by weight of the solid particles in the concentrated formulation may be greater than or equal to 6%, preferably greater than or equal to 10%, for example 20 to 35%. If an extreme pressure additive D is present, the concentrated formulation may comprise from 0.1% to 50% by weight of the extreme pressure additive, preferably 1% and 20%. Typically, the formulation may comprise from 0.1% to 6%, preferably from 0.2% to 3%, for example from 0.5% to 2.5%, by weight, of the amphiphilic compound C.

  It is noted that some of the additives may be added after dilution or on dilution.

  The concentrated formulation can be prepared from compound B in solid form, most commonly available commercially. For example, it is possible to start from an EGDS-based compound in the form of flakes, coarse powder, granules, or flakes, which are currently commercially available. In order to obtain the dispersion, the particles may in particular be carried out according to one of the following two methods: method A: grinding, then dispersion in the aqueous liquid vector. method B: hot emulsification in the aqueous liquid carrier, followed by cooling.

  The process for preparing the concentrated formulation may comprise in particular the following step II): Step II): at least a portion of the amphiphilic compound C is mixed with solid or liquid particles B, the particles and / or at least a part amphiphilic compound C being optionally premixed with the aqueous liquid carrier. Stage II) will generally be preceded by a stage I) for obtaining particles. It can be in particular one of the following steps: Step IA): a raw material is ground based on the compound B, so as to obtain a powder (comprising particles).

  Step IB): a raw material based on compound E3 is emulsified in the aqueous liquid carrier, preferably in the presence of heat, in the presence of at least a portion of the amphiphilic compound C.

  The grinding can be carried out by any known technique. Cold grinding processes are preferred, in particular for limiting the heating and melting of compound B. Cooled air jet milling operations make it possible to obtain powders of compound B, for example of particle size centered on 15 or 20 μm. . In particular grinding can be carried out using grinders available from Micro-Macinazione. The powder obtained can then be incorporated slowly with stirring (for example pale inclined faces, 200-400 rpm) in an aqueous solution of the amphiphilic compound B.

  Hot emulsification is particularly suitable for obtaining a fine particle size. Such a method is not suitable for the preparation of formulations and compositions based on EBS, which has a very high melting point, well above the boiling point of water, at atmospheric pressure. It is thus possible to mix water (for example about 70%) and compound B in solid form (for example about 30%) and to bring the mixture beyond the melting point of compound B. This can for example be carried out in an emulsification tool having a rotor / stator mixing system, for example the tool KORUMA DISHO 100/45. The speed of the rotor makes it possible to control the energy engaged in the system, and to control the size of the droplets of the compound B formed. Once the emulsion is obtained, it is diluted in cold water until the desired concentration of compound B is obtained. The solidification of the droplets then occurs, and the dispersion of solid particles is obtained. Preferably the cooling is brutal, uncontrolled, without a crystallization ramp. By this method, for example, it is possible to obtain particles having a size of approximately 0.3 μm, or 1 μm or 10 μm. The amphiphilic compound C is not necessary for producing the (hot) emulsion. It is however useful to ensure the stability of the dispersion once cooled. It can be added during the emulsification step, or after.

  According to particular embodiments, the lubricant composition (the dispersion) and / or the concentrated formulation is substantially free of paraffin particles with a straight chain, preferably paraffins in general, with a melting point greater than or equal to 71 ° C. or their halogenated derivatives, combined with sulfonated castor oil and / or a mixture of C4-C18 alkenyl succinic acid. According to more particular embodiments, the lubricating composition (the dispersion) and / or the concentrated formulation is substantially free of paraffin particles having a straight chain, with a melting point of greater than or equal to 71 ° C. or of their halogenated derivatives, associated with a anionic surfactant. By "substantially free" is meant less than 3%, preferably less than 1%, preferably less than 0.1%, preferably less than 0.01%, by weight of paraffin, preferably not at all.

  Use of Lubricating Composition - Metal Shaping The dispersion is used as a lubricating composition in a metal shaping process, with the exception of shaping reinforcing steel wires. a tire. Such methods are known to those skilled in the art. Metal shaping is often referred to as "metal working". In these processes, the metal object is deformed and / or cut using a tool, generally metal or based on a hard material (organic or inorganic polishing or scraping materials such as diamonds). The tool and the metal to be shaped are brought into contact with the lubricating composition. For example, the metal object and the tool can be immersed in a bath comprising the lubricating composition. In another mode, the tool and the metal object are not immersed in a bath, but the composition is poured or sprayed, preferably continuously, at the point of contact of the tool and the object, or upstream of this point of contact. The shaping of metals can in particular be a wire drawing (the metal object is then a wire, and the tool is a die), often called "wet wire drawing". The shaping can be a rolling, often called "wet rolling". The shaping can also be a cut. The shaped metal may in particular be a metal comprising iron, for example a metal comprising steel. According to one embodiment, it is not about aluminum or an aluminum-based alloy. Steels can be of varied hardness. The implementation of the invention may be particularly advantageous for relatively hard metals, especially for relatively hard steels with a relatively high carbon content. The shaped metal may in particular comprise a softer metal coating, for example a metal based on copper, zinc, and their alloys. It may especially be a brass coating. Such a coating can soften the contact between the tool and the shaped object, and facilitate the shaping. It can also provide the metal object with particular properties that are useful for the use that will be made of it. The invention can notably find a utility in the humic drawing to obtain a wire, preferably steel, intended to cut materials, to reinforce synthetic or natural rubber conduits where appropriate chemically modified, or to reinforce conveyor belts. Reinforced conduit wires are often referred to as "hose wire" conduit wires. Such conduits are for example of the type that can be found in service stations for the fuel supply of motor vehicles. The wire, preferably of steel, and preferably brass, may especially be used to cut materials. Such son are often called son of cut, or son of saw ("saw-wire" in English). The invention also relates to a method in which the wire is prepared, and then cutting a material using this wire. The principle of the yarn to cut the butter is known. Of course, the cutting wire can be used in devices and processes, and for more complex materials. Uses for cutting materials are known. The invention can notably make it possible to manufacture relatively high-density yarns more efficiently, and / or to make yarns of higher hardness. A high hardness can in particular confer an advantage in terms of low wear during cutting, and therefore in terms of cost effectiveness and efficiency of cutting. The invention can also make it possible to prepare metal wires, preferably made of steel, finer and thus improve the precision of the cuts and / or reduce the cutting waste (less sawdust). Among the materials that can be cut, mention is made of semiconductor materials, in particular for the production of wafers or silicon-based plates, in particular for producing solar panels.

  Some details are given below as to the drawing of metal wires that can be used in the context of the invention. The method comprises the following steps: starting from a wire, preferably steel, having an initial diameter preferably greater than 0.6 mm; it is stretched through a series of dies of decreasing diameter, in the presence of a lubricating composition in the form of an aqueous dispersion, to a predetermined final diameter, preferably less than 0.5 mm, the method being characterized in that said aqueous dispersion meets the main definition as well as the preferred characteristics stated above. Preferably, the wire, preferably steel, starting has a diameter greater than 0.8 mm, for example between 0.8 and 2.0 mm. The predetermined final diameter is preferably less than 0.45 mm, for example in a range of 0.1 to 0.4 mm. The number of dies is preferably between 10 and 40, for example in a range from 15 to 30. The section reduction ratio per die is typically between 3% and 25%. In a known manner, all the dies and therefore the wire itself being drawn are immersed in a so-called drawing bath, with the exception of the last die which may be immersed or in the open air, depending on the case. The wire is lubricated and cooled by the drawing bath, itself cooled by a circulation of water coupled to a heat exchanger. The operating temperature of the bath is preferably less than 40 ° C. The drawing speed, that is to say the output speed of the last die (equal to the winding speed of the drawn fine wire), is preferably comprised between 5 and 25 m / s (meters per second), for example in a range of 10 to 20 m / s. The invention is implemented on metal wires, preferably made of steel, more preferably carbonaceous perlitic (or ferritic-pearlitic) steel, hereinafter referred to as "carbon steel", or else stainless steel (by definition steel with at least 11% chromium and at least 50% iron). But it is of course possible to use other steels. When carbon steel is used, its carbon content is preferably between 0.4% and 1.2%, especially between 0.5% and 1.1%. It is more preferably between 0.6% and 1.0% (% by weight of steel), in particular between 0.68% and 0.95%; such a content representing a good compromise between the mechanical properties required and the feasibility of the son. It should be noted that in applications where the highest mechanical strengths are not necessary, it is advantageous to use carbon steels whose carbon content is between 0.50% and 0.68%, especially 0, 55% to 0.60%, such steels being ultimately less expensive because easier to draw.

  Another embodiment of the invention may also consist, depending on the end applications concerned, of using steels with a low carbon content, for example between 0.2% and 0.4%, especially because of a cost lower and easier to draw. The invention applies to a wet drawing process for obtaining any type of fine wire steel that is standard resistance (said NT for "Normal Tensile, high resistance (called HT for" High Tensile ' ), very high resistance (called SHT for "Super High Tensile") as ultra-high strength (so-called UHT for "Ultra High Tensile") The fine threads obtained by the drawing process of the invention can have a tensile strength (Rm denoted) which is preferably greater than 2000 MPa, for example between 2000 and 4000 MPa, more preferably greater than 2800 MPa, for example between 2800 MPa and 4500 MPa.The skilled person knows how to manufacture son of steel having such resistance, in particular by adjusting the carbon content of the steel and / or the hardening rates of these son.

  The steel used, whether it is for example a carbon steel or a stainless steel, can be a so-called "clear" steel (that is to say uncoated) or be coated with a metal layer improving for example the properties of implementation of the steel wire, its properties of use or those of any cable for which it is intended, such as for example the adhesion properties, corrosion resistance or resistance to aging. According to a preferred embodiment, the steel used is covered with zinc or with a zinc alloy, in particular brass (Zn-Cu alloy); it is recalled that during the wire drawing process, the brass or zinc coating is well known to facilitate the drawing of the wire. But the son could be covered with a thin metal layer other than a layer of brass or zinc, or a second layer used in addition to the first, having for example the function of improving the corrosion resistance of these wires, for example a thin layer of Co, Ni, Al, of an alloy of two or more compounds Cu, Zn, Al, Ni, Co, Sn.

  Other details or advantages of the invention may appear in light of the following examples, without limitation. Example 1 Preparation of concentrated formulations

  a) Raw materials used: - EGDS: Rhodia Alkamuls EGDS; scales of EGDS greater than 98% by weight; 20 - EBS: grade WAXSO MK, micronized with a median diameter of 15 μm from the company SOGIS Industria Chimica Spa; Paraffin: Sigma Aldrich product under No. 327204; linear saturated hydrocarbons having a melting point of about 55 C; - SC138: Antarox SC138 from Rhodia; polyoxyethylene and polyoxypropylene block copolymer (solid); - S40: Soprophor S40 from Rhodia; ethoxylated tristyrylphenol (solid); DSS7: Soprophor DSS7 Rhodia; sulphated ethoxylated distyrylphenol (viscous paste); - CS20: Rhodameen CS20 from Rhodia; ethoxylated fatty amine (liquid); Ethoxylated C12-C18 ester-phosphate of the Rhodafac product line of Rhodia.

  The experimental concentrated formulations, corresponding to the aqueous dispersions in diluted form C-2 to C-13 used in the following wire drawing tests, are given in Table 1 below (concentrations in% by weight of dry matter). Table 1 Composition EP-Surfactant Wax Granulometry Procedure Preparation C-2 EBS - 10% SC138 - 0.5 / Procedure 1 15%% C-3 Paraffin SC138 - 0.5% / Procedure 25% 10% C-4 EGDS 10% SC138 - 0.5% / Procedure 3 15 pm C-5 EBS 10% SC138 - 0.5% 0.5% Procedure 1 15 pm C-6 Paraffin SC138 -0.5% 0.5% Procedure 2 5 pm 10% C-7 EGDS - 10% SC138 -. 0.5% 0.5% Procedure 3 15 pm C-8 EGDS 10% S40 - 0.5% / Procedure 3 15 pm C-9 EGDS 10% DSS7 - 0.5% / Procedure 3 15 pm C-10 EGDS 10% CS20 - 0.5% / Procedure 3 15 pm C-11 EBS 10% S40 - 0.5% / Procedure 1 15 pm C-12 EBS 10% DSS7 0.5% / Procedure 1 15 pm C-13 EBS 10% CS20 - 0.5% Procedure 1 15 pm b) Preparation procedures: All formulations are at pH 8-9. At the end of the procedure, the pH is adjusted if necessary using diethanolamine or phosphoric acid. The indicated particle sizes are measured on a Horiba LA-910 (light scattering) apparatus, with a relative optical index of dispersed particles: 1.07-0.00i. The measurement is a volume average (that is, by weight) on the particle size distribution.

  The concentrated formulations prepared are 60 kg (total weight) of which: 10% by weight of dispersed solid particles; - 5% by weight of surfactant relative to the solid particles, ie 0.5% of surfactant relative to the total concentrated formulation; when a phosphate ester is added (C-5, C-6 and C-7): 5% by weight of EP relative to the dispersed particles, ie 0.5% of EP relative to the total concentrated formulation.

  Procedure 1 An aqueous solution of the surfactant is prepared, then the EBS is introduced into the aqueous solution, with moderate stirring (Rayneri type stirring motor, 200 rpm). If an extreme pressure additive is used, it is added last in the form of a concentrated aqueous solution, the pH of which is adjusted between 8 and 9 by addition of diethanolamine, with moderate stirring (Rayneri engine, 200 rpm). min). All operations are performed at room temperature (23 C).

  Procedure 2 An aqueous solution of the surfactant is prepared which is heated to a temperature of 10 ° C. higher than the melting point of the polymer used. The melted wax (at a temperature of 10 ° C. higher than the melting point of the wax used) is then introduced with stirring / grinding into the surfactant solution. This operation is conducted in a Koruma Disho 100/45 type apparatus. The size of the emulsion formed depends on the surfactant concentration, the speed (1000 to 3000 rpm) and the grinding time. The wax composition of this emulsion is 30%. The size of the melted wax droplets can be adjusted between about 0.2 μm and 10 μm. The emulsion is then diluted by a factor of three in cold water (5 C), simultaneously ensuring the quenching of the emulsion (and the solidification of the wax droplets) and the dilution at a concentration of 10% in wax . Depending on the amount of surfactant used to make the emulsion, surfactant is added to the dilution water to have a proper total surfactant composition. This operation is carried out in a tank cooled by water, with moderate agitation (Rayneri engine, 200 revolutions / min). If an extreme pressure additive is used, it is added last in the form of a concentrated aqueous solution, the pH of which is adjusted between 8 and 9 by addition of diethanolamine, with modified stirring (Rayneri engine, 200 turns / minute). min).

  Procedure 3 The scales of EGDS are crushed using an air jet mill at 0 ° C from Micro-Macinazione. The grinding energy (pressure and air flow) and the flow of EGDS are adjusted to obtain the indicated grain size. EGDS particles of size between 10 and 15 μm are obtained. An aqueous solution of the surfactant is prepared, and then the EGDS particles are introduced into the aqueous solution, with moderate stirring (Rayneri engine, 200 rpm). If an extreme pressure additive is used, it is added last in the form of a concentrated aqueous solution, the pH of which is adjusted between 8 and 9 by addition of diethanolamine, with moderate stirring (Rayneri engine, 200 rpm). min). The mixing operations are carried out at ambient temperature (23 ° C.).

  EXAMPLE 2 Wire Drawing Tests The following exemplary embodiments demonstrate that, in comparison with known solutions also using aqueous dispersions as a lubricating composition, the use in accordance with the invention unexpectedly leads to a higher property compromise. , this even in the presence of a lubricating composition of particularly simple formulation.

  In these examples, Steelcord thin carbon steel (NT type) fine wires coated with brass are made by wet drawing. Apart from the formulation of the drawing lubricant, these yarns are prepared in a known manner, for example starting from machine wires (diameter 5 to 6 mm) made of carbon steel (carbon content of about 0.7% i), that the It is first drawn by drawing (dry) to an intermediate diameter of about 1.5 mm and a strength of about 1100 MPa. After heat treatment and then deposition of a coating of brass (for example 64% copper) on these intermediate son, is carried out on each wire a so-called "final" work hardening by cold drawing in a humid medium, through a series of dies (about twenty in total) whose diameter decreases gradually (section reduction ratio by die between 3% and 25%), to obtain a final diameter of 0.28 mm. The lubricating wire drawing composition, in which the dies and the wire in formation are in a known manner immersed, is in all the examples in the form of an aqueous dispersion, one of them called "commercial" and several other experimental , the latter being in conformity or not with the invention. The so-called commercial lubricant composition is made from a concentrated aqueous formulation "Supersol 4419T" available from Rhodia, comprising particles based on EBS. It is used as a witness. For the sake of simplicity it is called "commercial formulation" or "commercial lubricant". In addition to the EBS particles, this concentrated commercial formulation includes various customary additives, including a surfactant and an ester-phosphate extreme pressure additive.

  The other experimental dispersions tested comprise, at a concentration of 1% by weight, solid particles of the following compounds (waxes): EGDS (ethylene glycol distearate); EBS (ethylene bis-stearamide); paraffin.

  As explained in detail below, these aqueous dispersions are stabilized by various known commercial surfactants, they may contain in some cases an extreme-pressure ester-phosphate additive. Experimental dispersions are prepared by dilution (up to a concentration of solid particles by weight of 1%) in water of experimental concentrated formulations, details of compositions and preparation of which have been given in the preceding paragraph.

  For comparison, the formulas for EGDS and EBS are as follows: (EGDS) H3C û (CH2) 16 ûCO2CH2 - CH2 - OCO2 (CH2) 16 - CH3 ( The performance in lubrication in the wet drawing machine is characterized by two parameters: the loss of brass (4). expressed as a percentage of the initially deposited mass of brass) is measured by the difference between the mass deposited on the wire of intermediate diameter and the mass measured on the final fine wire (at the output of the last die); it is estimated that a brass loss of less than 10% is indicative of a good quality of lubrication; - The die wear is characterized indirectly by measuring the increase in wire diameter after 30 kg of wire drawn wire to the theoretical diameter initially targeted.

  The fine yarn obtained is also characterized in tension in order to measure its maximum mechanical strength, denoted Rm (measured according to the ISO 6892 standard of 1984, from the Force-Elongation curve of the yarn tested). a) Test 1 In this first test, one compares with commercial lubricant "Supersol 4419T" mentioned above based on EBS (composition noted C-1), three experimental waxes (EBS, paraffin and EGDS), all three stabilized by the same agent surfactant known ("Antarox SC138" marketed by Rhodia) (compositions respectively noted C-2 to C-4). Only the use of the composition C-4 is therefore in accordance with the invention. Table 2 below summarizes the drawing results obtained with these four lubricating compositions. Table 2 Lubricant: Wear (pm for 30 kg) Rm (MPa) Brass loss (%) C-1 (control) 0 2950 9 C-2 (EBS) Undrawn wire - - C-3 (paraffin) Undrawn wire - Firstly, a comparison of the experimental compositions C-2, C-3 and C-4 clearly demonstrates the superiority of the EGDS wax compared with the two other waxes, since in these formulations very simplified, only the composition C-4 is able to draw a significant length of steel wire; with the other two compositions C-2 and C-3, it is simply impossible to draw (breakage of the wire even before reaching the nominal speed of wire drawing). Unexpectedly, the composition C-4 reveals an excellent lubricating power since, despite a formulation that could not be simpler (combination of a wax and a surfactant), results equivalent in terms of wear to those of commercial lubricant (Control C-1) which is itself fully formulated, and even improved with regard to the loss of brass. In particular, it can be deduced that, contrary to what was commonly accepted by those skilled in the art so far, the use of an extreme pressure type additive is not necessarily essential for the drawing of Steelcord steel wire; this is the case for the aqueous dispersion used according to the invention. b) Test 2 In this test is reproduced the previous test 1, this time adding, in addition to the surfactant (Antarox SC138), an ethylene-type C12-C18 ester-phosphate extreme pressure additive of the Rhodafac product range marketed. by Rhodia. Since the commercial lubricant (Composition C-1) is already formulated with an ester-phosphate additive, no other additive is added to it. Only the use of the composition C-7 is in accordance with the invention. Table 3 below summarizes the wire drawing results obtained with these four lubricating compositions. Table 3 Lubricant: Wear (pm / 30kg) Rm (MPa) Loss brass (%) C-1 (control) 0 2950 9 C-5 (EBS) 0 2825 5.8 C-6 (paraffin)> 10 2835 4 C-7 (EGDS) 0 2835 5.4 Compared to Table 2 above, Table 3 demonstrates that if the extreme pressure additive makes the experimental formulations (C- 5 and C-6) based on paraffin and especially on EBS capable of drawing, this additive brings on the other hand no visible improvement to the composition used in accordance with the invention (compare composition C-7 composition C-4 of previous test 1). In other words, the composition C-7 according to the invention, based on EGDS, is insensitive to the presence or absence of the extreme-pressure additive for good lubrication of the die. This is another remarkable and unexpected result for the skilled person.

  c) Test 3 In this test, the previous EGDS and EBS waxes are compared again, this time in the presence of four different surfactants (all marketed by Rhodia), all comprising at least one polyoxyethylene block as a hydrophilic unit and various hydrophobic units: a surfactant ("Antarox SC 138", solid), nonionic, of the polyoxyethylene and polyoxypropylene block copolymer type; a surfactant ("Soprophor S 40", solid), nonionic, of the ethoxylated tristyrylphenol type, comprising tristyrylphenol as a hydrophobic unit; a surfactant ("Soprophor DSS7", viscous paste), anionic, of the sulphated ethoxylated distyrylphenol type comprising distyrylphenol as hydrophobic unit; a surfactant ("Rhodameen CS 20", liquid) of the ethoxylated fatty amine type comprising an aliphatic chain as a hydrophobic unit.

  No other additive, in particular extreme pressure additive, is used in the experimental compositions tested. Only compositions C-4 and C-8 to C-10 are in accordance with the invention. The compositions C-2 and C-4 have already been tested in the preceding test 1. Table 4 below summarizes the drawing results obtained with these eight lubricating compositions. Table 4 Lubricant: Wear (pm / 30 kg) Rm (MPa) Brass Loss (%) C-4 (EGDS + 0 2930 3 SC138) C-8 (EGDS + S40) 4 2960 5.2 C-9 (EGDS + DSS7) 0.5 2880 4.5 C-10 (EGDS + 1.5 2895 5.2 CS20) C-2 (EBS + SC138) Undrawn wire - - C-11 (EBS + S40) Undrawn wire - - C-12 (EBS + DSS7) Wire not wire drawing - - C-13 (EBS + CS20)> 10 * not measured (wire obtained outside tolerances)

  The results in Table 4 clearly confirm the best performance of EGDS wax compared to EBS wax, regardless of the surfactant associated with it.

  It is furthermore noted that compositions C-4, C-9 and C-10 (in accordance with the invention) give an excellent performance from the industrial point of view, with a die wear rate of less than 2 pm combined with a loss of brass less than 10%. The best lubricant composition (C-4) is that based on EGDS and polyoxyethylene and polyoxypropylene block copolymer.

  For EBS, regardless of the surfactant used, the performance is either unacceptable or poor (composition C-13).

  Other wire drawing tests, which comply with and are not in accordance with the invention, were carried out starting from an intermediate wire made of steel with a higher carbon content (0.9%), with a diameter of around 1.3 mm. (Resistance Rm equal to about 1200 MPa), for obtaining son type SHT of final diameter 0.23 mm. The results obtained fully confirmed the results of tests 1 to 3 described above.

Claims (5)

  1. Use as a lubricating composition in a metal forming process, except for forming steel wires for reinforcement of a tire, dispersion in a liquid carrier aqueous composition of solid particles, at 23 ° C., of a compound B ester of a C 14 -C 22, preferably C 16 -C 22, fatty acid with a diol or a polyol, of formula (I) below: [R-COO- ] X A - [- OH] y (I) where: - R is a linear or branched, C15-C21, preferably C15-C21, saturated or unsaturated alkyl group; A is a hydrocarbon group, optionally interrupted; with one or more heteroatoms, of valence x + y, - x is an average number between 1 and 5, - y is an average number between 0 and 5, - x + y is an average number between 1 and 10, preferably between 2 and 5.   2. Use according to claim 1, characterized in that the particles have a particle size distribution with at least 90% by weight of particles of size between 0.1 and 50 pm.   3. Use according to one of the preceding claims, characterized in that: - A is a divalent group, and -y = 0.   4. Use according to the preceding claim, characterized in that the group A has the following formula: - (CH2) z- [OE] n- [OP] m- (CH2) z- where: 30 - z, identical or different is an integer from 1 to 10, - OE is an optional ethylene oxide group, and n is an average number of 0 to 100, preferably 0 to 10, and - OP is an optional propylene oxide group and m is an average number between 0 and 100, preferably 0 to 10. 35   5. Use according to one of the preceding claims, characterized in that A is a methylene, ethylene, propylene, butylene or a mixture of these groups.25 6 Use according to one of the preceding claims, characterized in that the group R-COO- is a C18i fatty acid, preferably stearic acid. 7 Use according to one of the preceding claims, characterized in that the compound B is a compound based on Ethylene Glycol Di-Stearate (EGDS). 8 Use according to one of the preceding claims, characterized in that the dispersion comprises from 0.05 to 6% by weight of the particles, preferably from 0.2 to 3% by weight. 9 Use according to one of the preceding claims, characterized in that the dispersion comprises a more at least one amphiphilic compound C. 10. Use according to claim 9, characterized in that the amphiphilic compound C is a surfactant. 11. Use according to one of claims 9 or 10, characterized in that the amphiphilic compound C is a nonionic amphiphilic compound. 1: 2. Use according to one of Claims 9 or 10, characterized in that the amphiphilic compound C is an anionic, cationic, amphoteric, zwitterionic or nonionic surfactant or a mixture of such surfactants. 13. Use according to one of claims 9 to 12, characterized in that the amphiphilic compound C is chosen from: cl) block copolymers of ethylene oxide and C3-C10 alkylene oxide, c2) ethoxylated and / or propoxylated di- or tristyrylphenols, and c3) fatty amines, optionally polyalkoxylated. 14. Use according to claim 13, characterized in that the block copolymer is a block copolymer of ethylene oxide and propylene oxide, preferably of structure [OE] n, - [OP], " [OE] n ', where: - EO is an ethylene oxide group, and n', the same or different, is an average number between 2 and 1000, and - OP is an optional propylene oxide group, and m is an average number between 2 and 1000.2015 Use according to one of claims 9 to 14, characterized in that the mass ratio between the amphiphilic compound C and the particles is between 1/100 and 10/100, preferably between 2.5 / 97.5 and 7.5 / 92.5 16. Use according to one of claims 9 to 15, characterized in that the dispersion comprises, in addition to or instead of the amphiphilic compound C, an additive Extreme pressure D, amphiphilic or not 17. Use according to one of the preceding claims, characterized in that the extreme additive ession is chosen from extreme pressure additives based on sulfur and / or phosphorus, preferably chosen from: - phosphate esters, optionally polyalkoxylated. 18. Use according to one of claims 16 or 17, characterized in that the dispersion comprises from 0.01% to 5% by weight of the extreme pressure additive, preferably from 0.1% to 2%. 19. Use according to one of the preceding claims, characterized in that the dispersion is obtained by dilution in water, of a concentrated formulation comprising: - the aqueous liquid carrier, - the solid particles, - optionally a compound amphiphilic C, and 25 - optionally an extreme pressure additive D. 20. Use according to one of the preceding claims, characterized in that the dilution is from 0.5 to 18 parts, preferably from 1 to 6 or 10 parts of formulation concentrated for 100 parts of liquid vector. 21. Use according to one of the preceding claims, characterized in that the metal shaping process is a wet wire drawing process, or a wet rolling process. 22. Use according to one of the preceding claims, characterized in that the shaped metal comprises steel and optionally a metal coating, preferably based on brass. 2: 3. Use according to claim 21 or 22, characterized in that the metal shaping process is a wet drawing process for obtaining a wire for cutting materials, reinforcing synthetic rubber ducts or natural if necessary chemically modified, or to reinforce conveyor belts. 24. A process for the wet wire drawing of a wire, preferably a steel wire, with the exception of metal wires intended for reinforcing a pneumatic tire, comprising the following steps: starting from a wire steel having a diameter greater than 0.6 mm; it is stretched through a series of dies of decreasing diameter, in the presence of a lubricating composition in the form of an aqueous dispersion, to a predetermined final diameter of less than 0.5 mm, said process being characterized in that said aqueous dispersion is as defined in any one of the preceding claims 1 to 20. 25. The method of claim 24, wherein the starting wire has a diameter greater than 0.8 mm. The method of claims 24 or 25, wherein the predetermined final diameter is less than 0.45 mm. 27. A process according to any one of claims 24 to 26, wherein the number of spinnerets is between 10 and 40. 28. A method according to any one of claims 24 to 27, wherein the section reduction rate. per sector is between 3% and 25%. 29. A method according to any one of claims 24 to 28, wherein the drawing speed is between 5 and 25 meters per second. 30. Concentrated lubricant formulation comprising: - the aqueous liquid carrier, dispersed in the aqueous liquid carrier, solid particles, at 23 ° C., of a compound B ester of a C 16 -C 22 fatty acid, preferably C 16 -C22 with a diol or a polyol of the following formula (I): ## STR3 ## wherein: R is a linear or branched alkyl group, saturated or unsaturated; , C15-C21, preferably C15-C21, - A is a hydrocarbon group, optionally interrupted by one or more heteroatoms, of valence x + y, - x is an average number between 1 and 5, - y is a number average between 0 and 5, - x + y is an average number between 1 and 10, preferably between 2 and 5 an amphiphilic compound C, and optionally an extreme pressure additive D. 31. Formulation according to claim 30, characterized in that that the particles have a particle size distribution with 90% by weight of particles of size between 0.1 and 50 pm. 32. Formulation according to one of claims 30 or 31, characterized in that: - A is a divalent group, and - y = 0. 33. Formulation according to the preceding claim, characterized in that the group A has the following formula: - (CH2) Z [OE] n- [OP] m- (CH2) Z where: 25 - z, identical or different, is an integer from 1 to 10, - OE is an optional ethylene oxide group, and n is an average number between 0 and 100, preferably 0 to 10, and - OP is an optional propylene oxide group, and m is an average number of between 0 and 100, preferably 0 to 10. 34. Formulation according to one of claims 30 to 33, characterized in that A is a methylene, ethylene, propylene, butylene or a mixture of these groups. 35. Formulation according to one of claims 30 to 34, characterized in that the R-COO- group corresponds to a C18 fatty acid, preferably stearic acid. Formulation according to one of claims 30 to 43, characterized in that it is a concentrated formulation, comprising at least 6%, preferably at least 10%, by weight, of the particles.