Adhesive composition for textiles and related reinforcing textiles

Abstract

Adhering composition for textile and related reinforcing textile The invention relates to an adhesive composition for textile, comprising a lignosulfonate salt, an epoxy hardener of this salt, and an elastomer latex. The lignosulfonate salt may be a sodium, potassium, magnesium, ammonium or calcium lignosulfonate. The invention also relates to the use of such a composition for conferring adhesion properties to a reinforcing textile, with respect to a rubber, a reinforcing textile, in particular a thread, cable or textile structure, at least partially coated and / or impregnated with this composition, and a part made of rubber or comprising a rubber, in which the rubber comprises at least one reinforcing textile, on the surface and / or integrated inside the rubber. Figure for the abstract: None

Description

Title of the invention: Adhesion composition for textiles and related reinforcing textiles

[0001] The present invention relates to an adhesive or bonding composition for textiles, in particular a composition for making a textile adhere to rubber. The invention relates in particular to applications in the field of belts, pipes, tires, air springs and, more generally, any part or article made of rubber, or comprising a part made of rubber, in which the rubber comprises a textile reinforcement on the surface and / or in depth (in the mass). The invention therefore also relates to textile reinforcements coated with this adhesive, and to parts or articles incorporating them both on the surface and in depth.

[0002] Background of the invention

[0003] To take the example of transmission belts, the textile reinforcement must primarily ensure the dimensional stability of the belt. To achieve this, the reinforcement is required to have specific mechanical properties in various environments. To guarantee the required properties, and in particular to avoid a risk of delamination, the reinforcement must adhere to the rubber of the belt. The reinforcement may be in contact with one or more different rubbers. To ensure good compatibility with the rubber, the reinforcement is generally treated with an adhesive. More complex properties may also be required of the reinforcement. For example, since the edge of the reinforcement is cut and exposed to the side of the belt, it must not fray, while being easy to cut. To guarantee these other properties, other types of treatments can be applied to the yarn.

[0004] Since several different treatments are applied to the textile reinforcement, it is imperative to ensure the compatibility of the adhesive with the reinforcement, the rubber and also the other treatments applied to the reinforcement.

[0005] To obtain all of these properties, it is necessary to provide a construction to the wire, in particular in the form of a cable, and to provide several chemical and thermal treatments.

[0006] Chemical treatments are primarily aimed at making a given reinforcement adhere to the different rubbers it may encounter. The treatments are as varied as there are types of reinforcement [glass, aramid, polyamide (PA), polyethylene terephthalate (PET), etc.] and families of rubber.

[0007] The heart of the treatment for making a reinforcing textile adhere to rubber is what is called the resorcinol-formaldehyde-latex or RFL treatment. This is a system mixing a latex (colloidal aqueous dispersion of elastomer or polymer) and thermosetting resins of the phenoplast or aminoplast type. This system is historic, it was widely developed in the 70s and remains the preferred treatment. Despite numerous attempts at replacement, it has never been possible to offer a global solution allowing it to achieve its performance. It is completely optimized to obtain maximum static adhesion, i.e. without dynamic stress.

[0008] Heat treatment has an impact on the chemical properties (adhesion) but also mechanical properties in the case of synthetic reinforcements. It impacts the shrinkage characteristics, among others. Treatment in ovens results from the consensus between maintaining the mechanical properties and the crosslinking of the adhesive.

[0009] For all these reasons, the new treatment must therefore be able to adapt to current processing conditions, in order to guarantee the mechanical properties. However, an adhesive allowing processing at a lower temperature will potentially provide new and interesting properties in certain applications, and will have a favorable energy aspect.

[0010] However, to improve adhesion performance, or to provide abrasion resistance, up to four different treatments may be applied successively to a textile, including treatment with RFL. These are the following treatments:

[0011] 1. The core treatment of the yarn which allows the filaments to be trapped in a matrix and the filaments to be locked together. It thus provides resistance to fraying and makes the yarn stiff. 2. Pre-activation, to improve adherence. 3. RFL treatment, in one or two layers. 4. Overcoats in the form of commercial adhesion promoters, or elastomer dissolutions (sometimes called cementation).

[0012] It is therefore also preferable that any change in a formulation does not call into question the functionality of the various treatments, both chemical and thermal (or physical, more generally) usually used for this or that application.

[0013] Considering all the constraints mentioned, the RFL treatment has established itself as the treatment of choice to enable adhesion between the textile and the rubber. The phenomena involved in adhesion are brought into play during the vulcanization of the rubber part, whereas the RFL treatment itself can be deposited on the textile several months before. This is why the term "adhesion" treatment is often used, the term "adhesion" being rather reserved for the state of adhesion. In the RFL, the latexes are colloidal aqueous dispersions of elastomers or polymers, generally similar in nature to the rubber to be bonded. However, these latexes do not have any real mechanical properties in themselves. To ensure the system holds together, a thermoset resin (thermosetting) is added. This is the RF resin, based on resorcinol and formaldehyde. Through its polarity, it allows good adhesion to the textile. It forms a mesh in which the latex is trapped, which stiffens the system. This mesh remains sufficiently flexible to allow the diffusion of the elastomer chains in the matrix and thus create good adhesion to the rubber (entanglement, molecular interactions and possibly co-crosslinking during vulcanization).

[0014] RFL contains formalin and resorcinol, which are currently suspected carcinogens. It would therefore be interesting to find an alternative to this formalin and resorcinol or to the RFL composition as a whole. The complex properties of RFL, both in terms of its implementation and in the usage properties of the final products incorporating it, which have been recalled above, make the exercise of finding an alternative solution a real challenge. It would be even more interesting to find such a solution that is more than an alternative, but which allows an increase in performance. It is to meet these challenges that the inventors have set out.

[0015] The invention thus aims to provide new adhesion solutions which in particular make it possible to replace RFLs in their known applications, with similar or even higher performance levels, and this with components which are acceptable in the context of sustainable development and under favorable economic conditions.

[0016] Lignosulfonates are proposed as a natural adhesive and as a short fiber binder for the production of mats (nonwovens) in combination with lignosulfonate hardeners, or as adhesives in wood-based multilayer products. They have never been proposed in alternative compositions to RFL and there is no indication that lignosulfonates may prove suitable for developing adhesion formulas to ensure a bond with rubbers, with sufficient mechanical performance. Summary of the invention

[0017] The subject of the invention is therefore a composition comprising (or based on, consisting essentially of, or consisting of) a lignosulfonate salt, an epoxy hardener of this salt, and a polymer latex, in particular an elastomer. It is in particular an adhesive or bonding composition for textiles.

[0018] The invention also relates to a composition, in particular an adhesive or bonding composition for textiles, obtained or capable of being obtained by mixing a lignosulfonate salt, an epoxy hardener of this salt, and a polymer latex, in particular elastomer. In one embodiment, the composition is as obtained or capable of being obtained by mixing a lignosulfonate salt and an epoxy hardener of this salt, in a basic medium, then adding a polymer latex, in particular elastomer; or by mixing a lignosulfonate salt in a basic medium and a polymer latex, in particular elastomer, then adding an epoxy hardener of this salt.

[0019] The invention also relates to a composition, in particular an adhesive or bonding composition for textiles, comprising the product of the reaction between a lignosulfonate salt, an epoxy hardener of this salt, and a polymer latex, in particular an elastomer. In one embodiment, the composition comprises the product of the reaction between a lignosulfonate salt in a basic medium and an epoxy hardener of this salt, then addition of a polymer latex, in particular an elastomer; or the product of the reaction between a lignosulfonate salt in a basic medium and a polymer latex, in particular an elastomer, then addition of an epoxy hardener of this salt.

[0020] The compositions may be adhesion compositions for making textiles adhere to a rubber or a similar material. These compositions are the compositions which can be applied to a substrate, such as in particular a textile, in particular the textiles according to the invention. The invention also relates to their preparation process.

[0021] The invention also relates to these compositions dried and hardened after suitable treatment such as heat treatment. These dried and hardened compositions are then generally associated with a substrate, such as in particular a textile, in particular the textiles according to the invention, or even with rubber parts, or the like, incorporating these textiles. By associated, it is meant that the composition impregnates the textile, coats the textile, or impregnates and coats the textile. The coating can be continuous or discontinuous. The impregnation can be complete and at the core or partial.

[0022] The invention also relates to a kit or set comprising a first composition comprising a lignosulfonate salt and a polymer latex, in particular an elastomer, and a second composition comprising an epoxy hardener of the lignosulfonate salt. The first and second compositions are suitable and intended to be mixed to form the adhesion composition, before the application of the latter to a textile within the meaning of the invention.

[0023] The invention also relates to a method of applying an adhesion composition according to the invention, to confer adhesion properties to a reinforcing textile, with respect to a rubber or a similar material. This method will comprise drying and hardening the composition, by a suitable treatment such as a heat treatment.

[0024] The invention also relates to the use of a composition according to the invention or of a dried and hardened adhesive composition, for conferring adhesion properties to a reinforcing textile, with respect to a rubber or a similar material.

[0025] The invention also relates to a reinforcing textile, in particular yarn, cable or textile structure, at least partially coated and / or impregnated with an adhesion composition according to the invention, in particular dried and hardened.

[0026] The invention also relates to an article or part made of rubber (or similar material) or comprising a part made of rubber (or similar material), in which the rubber comprises at least one reinforcing textile according to the invention, on the surface and / or integrated inside the rubber or the rubber matrix.

[0027] Other objects of the invention will appear on reading the detailed description which follows. Detailed description

[0028] The invention therefore has as its first subject an adhesive or bonding composition for textiles, comprising (or based on, consisting essentially of, or consisting of) at least one lignosulfonate salt, at least one epoxy hardener of this salt, and an elastomer latex.

[0029] Without wishing to be bound by theory, it is believed that the lignosulfonate salt and the epoxy hardener of this salt, by definition, react together to give a reaction product when their mixture is subjected to heat during a heat treatment, such as a heat treatment which will be applied to the textile once coated and / or impregnated with the adhesion composition. However, the possibility of one or more reaction mechanisms between the lignosulfonate salt and the epoxy hardener possibly catalyzed by the basic medium, during the preparation and / or storage time of the adhesion composition cannot be excluded. By "reaction product", we understand as goes without saying the product of the reaction between the lignosulfonate and the epoxy, which does not include any additives which could enter into the final composition.

[0030] Drying means evaporation of water. Hardening or heat-setting means catalysis of the reactivity of the chemical species deposited on the textile. The heat treatment applied allows drying and hardening, or drying and heat-setting.

[0031] This composition can in particular be obtained by a process, also the subject of the invention, according to which the three ingredients are mixed with stirring.

[0032] As illustrated in the examples, according to a first embodiment, the lignosulfonate salt can be solubilized in water, before mixing the solution obtained with the latex and the epoxy. This solubilization can be facilitated by working in a basic medium, by adding an agent such as sodium hydroxide and / or ammonia. According to one method, the lignosulfonate salt solution and the latex are first mixed, and only then is the epoxy added. According to another method, the lignosulfonate salt solution is first mixed sulfonate and the epoxy hardener, and only then is the latex added, thus constituting two methods. Note that, unless otherwise indicated, the term "addition" may mean adding the first product to the second, or vice versa.

[0033] In one embodiment of the preparation process, the lignosulfonate salt can be dissolved in water with stirring and in the presence of the agent allowing it to be at a basic pH, stirring until solubilization, preferably complete, it is then added, while stirring, to the latex, before incorporating, still with stirring, the hardener (preferably the latter is previously dissolved or dispersed in water, e.g. with vigorous stirring). According to a practical method, the mixture of lignosulfonate salt and latex is added to the epoxy hardener solution or dispersion. The mixing with the epoxy hardener can be carried out in the continuation of the preparation of the lignosulfonate and latex mixture, or subsequently, as in the case of the kit or set which is the subject of the invention. The composition can be used as a ready-to-use adhesion composition or one which can be diluted to order.

[0034] According to another embodiment of the method, an aqueous solution of lignosulfonate and epoxy hardener can be mixed, before adding the mixture with stirring to an aqueous latex dispersion. According to a practical method, the lignosulfonate salt and epoxy hardener mixture is added to the latex. Advantageously, the pH of the lignosulfonate or lignosulfonate and hardener solution is adjusted to be basic, for example by adding sodium hydroxide and / or ammonia, before incorporating the latex. The composition can be used as a ready-to-use adhesion composition or one that can be diluted to order.

[0035] The following characteristics apply to the different objects of the invention.

[0036] The latex is preferably a basic aqueous dispersion of the polymer(s) and / or elastomer(s). It is also possible to work according to the invention at neutral pH. The working pH values may in particular be those mentioned below with regard to the pH of the composition.

[0037] The term "elastomer" means, in particular, a polymer or copolymer chain whose glass transition temperature (Tg) is less than approximately 25°C. The elastomers are present in the rubber to be adhered and in the latex of the adhesion composition. An "elastomer latex" is a colloidal aqueous dispersion of elastomer.

[0038] By "rubber" (in English "rubber") or "elastomeric material" is meant here the vulcanized or crosslinked product prepared from elastomer or elastomeric gum, synthetic or natural, of one or more types, reinforcing filler(s) (carbon blacks, silica, kaolins, etc.), plasticizer(s), vulcanizing agent(s) (sulfur, peroxide, metal oxides and the necessary accelerators), possible other additives usual for the application considered (for example to facilitate the setting in work, for protection against oxygen, ozone, heat, flame, UV). The invention concerns both synthetic rubbers and natural rubber. Rubbers, formulated on the basis of elastomers, are materials whose Tv obtained is then lower than the service temperature of the part.

[0039] Lignosulfonates are by-products of wood processing, particularly from the treatment of wood for the manufacture of paper pulp using the so-called “bisulfite acid cooking process”. This process, which uses a bisulfite, allows, depending on the nature of the counterion used, the corresponding lignosulfonate salts to be obtained. These lignosulfonates can also be derived from a process intended to produce them from wood.

[0040] Preferably, in the adhesion composition, the lignosulfonate salt may be a sodium, potassium, magnesium, ammonium or calcium salt.

[0041] In an exemplary embodiment, lignosulfonates prepared by the bisulfite process from maritime pine, for example from Landes (France), are used.

[0042] Preferably, the bonding compositions do not comprise formaldehyde or formalin. Preferably, the bonding compositions do not comprise resorcinol. Preferably, the bonding compositions do not comprise formaldehyde or formalin, nor resorcinol. Preferably, the bonding compositions do not comprise an organic solvent. They use water as a solvent, the pH of which can be adjusted as needed.

[0043] The epoxy hardener according to the invention is a compound containing at least one epoxy group or unit. These hardeners are in particular polyepoxy compounds, comprising at least 2 epoxy groups or units. In particular, those which comprise on average more than one glycidyl or -methyl-glycidyl radical carried by a hetero-atom, preferably an oxygen or nitrogen atom, more particularly an oxygen atom, or those which contain on average more than one epoxy-cyclohexyl group. It is possible to use several different compounds from the lists which follow.

[0044] The following hardeners may be mentioned in particular:

[0045] - diglycidyl or polyglycidyl ethers of aliphatic polyols, - diglycidyl or polyglycidyl ethers of polyfunctional phenols, - polyglycidyl ethers of condensation products of phenols with formaldehyde obtained under acidic conditions, - di- or polyglycidyl esters of aliphatic or aromatic polycarboxylic acids, - compounds with epoxycyclohexyl groups, - polyepoxide compounds resulting from the epoxidation of an olefinically unsaturated compound

[0046] We can mention in particular:

[0047] - diglycidyl or polyglycidyl ethers of aliphatic polyols such as 1,4-butanediol, 1,6-hexanediol, 1,2,6-hexanetriol, glycerol, neopentyl glycol, ethylene glycol, triethylene glycol, 1,2-propylene glycol or polyalkylene glycols such as polypropylene glycols, or derivatives of polyalkylene glycols, for example polypropylene glycols; - diglycidyl or polyglycidyl ethers of polyfunctional phenols such as 2,2-bis(4-hydroxyphenyl)propane (or BPA), 2,2-bis(4-hydroxyphenyl)hexafluoropropane (or BPA-F), 1,1-bis(4-hydroxyphenyl)-1-phenyl-ethane (or BPA-P), 2,2-bis(4-hydroxyphenyl)butane, (BPB), bis-(4-hydroxyphenyl)diphenylmethane (or BPBP), 2,2-bis(3-methyl-4-hydroxyphenyl)propane (or BPC), bis(4-hydroxyphenyl)-2,2-dichloroethylene (or BPCII), bis(4-hydroxyphenyl)methane (or BPF), 4,4'-(9H-fluoren-9-ylidene)bisphenol (or BPFL), 2,2-bis(4-hydroxy-3-isopropylphenyl)propane (or BPG), l,3-bis(2-(4-hydroxyphenyl)-2-propyl)benzene (or BPM), l,l-bis(4-hydroxyphenyl)cyclohexane (BPZ) and the like; - polyglycidyl ethers of condensation products of phenols with formaldehyde obtained under acidic conditions: phenol novolaks and cresol novolaks and the like; - ethers of compounds containing epoxycyclohexyl groups such as 3,4-epoxycyclohexylmethyl 3,4 epoxycyclohexanecarboxylate, 8,9-epoxy-3,4-(epoxycyclohexyl)-3-di-oxa-2,4 spiro 5,5 undecane and bis-(3,4-epoxycyclohexylmethyl) adipate, and the like; - di- or polyglycidyl esters of polycarboxylic acids such as phthalic acid, terephthalic acid, A-tetrahydrophthalic acid, hexahydrophthalic acid, trimellitic acid, oxalic acid, succinic acid, glutaric acid, dimerized linolenic acid and the like.

[0048] The epoxy hardener may in particular be chosen from the compounds below, it being understood that the composition may incorporate one of them or several of them, in particular 2 of them:

[0049] - 1,4 butanediol diglycidyl ether (Diglycidyl ethers of polyols ali phatic) - 2,2-bis(4-hydroxyphenyl) propane diglycidyl ether (Diglycidyl ethers of polyfunctional phenols) - Diglycidyl 1,2-cyclohexanedicarboxylate (Di- or polyglycidyl esters of polycarboxylic acids) - 3,4-epoxycyclohexylmethyl 3,4 epoxycyclohexanecarboxylate (Compounds with epoxycyclohexyl groups) - 1,6 hexanediol diglycidyl ether (Diglycidyl ethers of polyols ali phatic) - Glycerol diglycidyl ether (Diglycidyl ethers of aliphatic polyols) - Glycerol triglycidyl ether (Polyglycidyl ethers of aliphatic polyols) - Mixture of glycerol diglycidyl ether and glycerol triglycidyl ether, eg marketed by the Raschig Company under the reference GE 100 (Diglycidyl ethers of aliphatic polyols) - Novolac type epoxy resins, e.g. marketed by HUNTSMAN Company under the reference Araldite PZ 323 (Polyglycidyl ethers of condensation products of phenols with formaldehyde)

[0050] The epoxy hardener may also be chosen from N-glycidyl derivatives of amines, amides and heterocyclic nitrogen bases, for example: - N,N-diglycidylaniline, - N,N-diglycidyltoluidine, - N,N,N',N' tetrakis-glycidyl bis-(4-aminophenyl)-methane, - the triglycidyl derivative of 4-hydroxyaniline, - triglycidyl isocyanurate, - N,N'-diglycidyl-ethyleneurea, - N,N'-diglycidyl-5,5-dimethylhydantoin, - N,N'-diglycidyl-5-isopropylhydantoin and - N,N'-diglycidyl-5,5-dimethyl-6-isopropyl-5,6-dlhydrouracil.

[0051] The latex may advantageously be a carboxylated acrylonitrile / butadiene copolymer latex (XNBR), a hydrogenated acrylonitrile / butadiene latex (HNBR), a chlorosulfonated polyethylene latex (CSM), a styrene-butadiene-vinylpyridine copolymer latex (VPSBR), a styrene / butadiene copolymer latex (SBR), an acrylonitrile / butadiene copolymer latex (NBR), a polybutadiene latex (BR), a chlorobutadiene latex (CR), a natural rubber latex (NR), a polyurethane latex, or a mixture of at least two of them.

[0052] The mass content of dry matter in the composition may be in particular between approximately 2 and approximately 38%, in particular between approximately 4 and approximately 30%, more particularly between approximately 7 and approximately 25%.

[0053] The composition according to the invention may in particular comprise from approximately 40 to approximately 95%, preferably from approximately 55 to approximately 90% or from approximately 40 to approximately 60, 70, 80 or 90% by mass of elastomer relative to the composition.

[0054] Unless otherwise indicated, the composition is given in dry matter.

[0055] In the composition, the hardener / lignosulfonate salt mass ratio may be in particular between approximately 0.01 and approximately 5, more particularly between approximately 0.03 and approximately 1, typically between approximately 0.05 and approximately 0.5. Values lower or higher may be possible depending on the hardener and lignosulfonate salt pairs chosen and this parameter can be determined by those skilled in the art on the basis of this description.

[0056] In the composition, the mass ratio [hardener + lignosulfonate salt] / latex may be in particular between approximately 0.05 and approximately 0.6, more particularly between approximately 0.15 and approximately 0.5. Lower or higher values may prove possible depending on the compounds chosen in combination and this parameter can be determined by a person skilled in the art on the basis of this description.

[0057] According to an advantageous characteristic, the composition has a neutral or basic pH, in particular a pH of between approximately 7 and approximately 13, in particular between approximately 9 and approximately 13. The composition may comprise for this purpose an additive making it possible to adjust the pH, for example soda.

[0058] The composition comprises the water of the elastomer latex. Water may further be added, in order to make the applicable composition sufficiently fluid for conventional application, for example by impregnation.

[0059] The composition may also comprise additives at a content in particular of between approximately 0.01 or 0.1 and approximately 50% by dry mass. The composition may in particular comprise an adhesion promoter or adhesion promoter soluble in an aqueous medium (for example, silane, blocked isocyanate), a surfactant, a dispersant, an anti-foaming agent, a wax (for example, microcrystalline hydrocarbon wax in emulsion), a filler (for example, carbon black, silica), a colorant, a metal oxide (for example, zinc oxide ZnO), an elastomer crosslinker, an anti-UV agent, an anti-ozone agent, a heat-protective agent. These agents are additives conventionally used in RFL formulations. They are compatible with the adhesive that is the subject of the invention.

[0060] In one embodiment, the textile adhesive composition consists essentially of a lignosulfonate salt, an epoxy hardener, this salt, and an elastomer latex, and may comprise one or more additives, in particular one or more of the additives mentioned in the preceding paragraph. Advantageously, the compositions according to the invention do not comprise a conventional hardener or catalyst for compounds with an epoxy group or unit, such as triethylenetriamine (TETA) and triethylamine (TEA).

[0061] The viscosity of the adhesion composition, measured at 23°C using a Brookfield viscosimeter as detailed in the Examples section, may in particular be between approximately 1 and approximately 5, for example between approximately 1.5 and approximately 4.5, Cp or mPa.s. This viscosity can easily be adjusted by varying the water content, in particular.

[0062] The composition according to the invention can be applied to any textile. By "textile" for the purposes of the invention, the following are understood to mean: continuous monofilament yarn, continuous multifilament yarn, staple fiber or yarn, any assembly of continuous monofilament and / or multifilament yarns or of staple fiber, in particular a roving, a cable formed from such yarns by conventional twisting techniques and a “textile structure” formed from the assembly of yarns, twisted or cabled, in particular in the form of fabric, grid, etc. The textiles of the invention, having been treated with the composition according to the invention, are designated by the expression “reinforcing textiles”.

[0063] The textile may be of organic or inorganic nature. As textile nature, we may cite in particular glass (in particular E glass or high modulus glass), basalt, carbon, aramid (meta or para), polyvinyl alcohols, cellulose, high density polyethylenes (HDPE), polyesters (in particular polyethylene terephthalates, PET), polyamides (PA, in particular PA 4.6, PA 6.6, PA 6), acrylics, hybrids (aramid yarn + nylon yarn, cabled together; acrylic + glass + copper, cabled together), etc. When the textile is a cable or a textile structure of several yarns, the yarns may all be of organic or inorganic nature, or the cable or the textile structure may comprise both types of yarns, organic and inorganic.

[0064] The invention also relates to a method of applying, or the use of, an adhesion composition according to the invention, to confer adhesion properties to such a textile, in particular with respect to an elastomeric material. This use can be broken down into terms of a method of adhesion of a textile according to the invention. This use or this method comprises the application of said composition to the textile (yarn, cable, textile structure), then its drying. This application can be carried out by the methods used in industry, for coating, in particular by impregnation, as described below. The choice of latex, therefore of the constituent elastomer, advantageously tends towards a formula similar to the nature of the constituent elastomer of the rubber to be treated.

[0065] In one embodiment, the impregnation of the textiles is carried out by dipping in tanks containing the adhesive preparations.

[0066] The threads, ropes and cables may in particular undergo either direct dipping in a tank or impregnation by a licking roller, for the application of the adhesion composition. After dipping or impregnation, the excess wet preparation is preferably removed, for example by pressing (rolling), die, suction or by physical compression between porous supports such as foams. After dipping or impregnation, and possibly removal of the excess, the adhesion composition is then dried and heat-set. The coated impregnated textile may thus undergo passage through an oven to allow the drying and crosslinking of the adhesion composition. After leaving an oven, the textile may again undergo an impregnation step (by dipping or impregnation by licking roller), then passing through an oven, these steps being able to be repeated, in particular up to a total of 4 impregnations (2, 3 or 4).

[0067] In another impregnation method, particularly suitable for mineral fibers (glass, basalt, carbon, etc.), a breaking system composed of a comb and / or “pigtails” can be used before impregnating a multifilament yarn. It allows maximum opening of the multifilament yarn, to promote strong impregnation. After soaking or impregnation with a licking roller as above, the excess wet preparation is preferably removed, for example by pressing (piling), suction or by physical compression between porous supports such as foams. After soaking or impregnation, and possibly removal of the excess, the adhesion composition is then dried and heat-set. The coated impregnated yarn can thus undergo passage through an oven to allow drying and crosslinking of the adhesion composition.After leaving an oven, the wire can again undergo an impregnation step (by dipping or impregnation by licking roller), then passing through an oven, these steps can be repeated, in particular up to a total of 4 impregnations (2, 3 or 4).

[0068] After the steps of impregnating and drying and heat-setting a yarn, the yarn is then twisted in line. The cabling is preferably carried out on an already treated yarn, but it is also possible to carry out the cabling and then carry out the steps of impregnation and drying and heat-setting. In the different processes, the speeds can range from 1 m / min to 150 m / min, the oven temperatures from 30°C to 350°C, more specifically from 100 to 300°C, and even more specifically from 140 to 220°C. Mechanical tension can also be applied to the textile throughout the process.

[0069] One embodiment relates to the production of a textile reinforcement for incorporation into assemblies such as transmission belts or conveyor belts. For this, a cord, for example made of polyamide such as PA 4-6, is constructed by twisting and then cabling. The cord obtained may optionally and advantageously be treated by a first core impregnation intended to lock the filaments together and give the yarn resistance to fraying, also making the yarn stiff; this may be achieved with a solution of methylene diphenyl diisocyanate in toluene; the impregnated cord is then subjected to drying and heat-setting in an oven. The cord is then impregnated in a tank containing an adhesive composition of the invention, then dried and heat-set in the oven.

[0070] Another embodiment relates to the production of a textile reinforcement for incorporation into profiles and seals, such as window or door seals. Such reinforcements can in particular be made from glass yarn containing a size with which the adhesive composition must be compatible. It is possible to proceed from glass threads (especially E glass), they are subjected to unraveling (see above) and impregnation in the tank containing an adhesion composition of the invention. The impregnated threads were subjected to drying and heat-setting in an oven. Upon leaving the oven, the threads undergo a twisting operation. A plurality, for example three, impregnated twists can then be cabled together.

[0071] Another embodiment relates to the production of a textile reinforcement to serve as reinforcement, braided, spiraled, covered or knitted in a brake pipe. It is possible to start from a thread made of organic material, for example polyethylene terephthalate (PET), high density polyethylene (HDPE), or polyamide. A twist is preferably applied to it. The thread, preferably twisted, is treated by impregnation in an adhesion composition of the invention, then by drying and heat setting in an oven.

[0072] As a variant of this embodiment, starting from similar yarns, a cable is constructed by successive stages of twisting, then cabling. The cable obtained is treated by a first core impregnation intended to block the filaments together and give the yarn resistance to fraying, also making the yarn stiff, for example using a solution of methylene diphenyl diisocyanate in toluene, then subjected to drying and heat-setting in an oven. The cable obtained is then treated by impregnation in an adhesion composition of the invention, then by drying and heat-setting in an oven.

[0073] Other characteristics of the use or method will appear upon reading the remainder of the description.

[0074] The invention also relates to a reinforcing textile coated and / or impregnated with an adhesive composition according to the invention. The invention particularly relates to a reinforcing textile coated and / or impregnated with an adhesive composition capable of being obtained by implementing the methods described here. It also relates to the method of treating the textile to produce the reinforcing textile, by applying the adhesive composition to said textile.

[0075] The invention relates in particular to a yarn coated and / or impregnated with an adhesive composition according to the invention. The yarn may be a twisted yarn, and the twisting may take place before or after application of the composition, and solidification thereof. When the yarn is multifilament, it may be impregnated to the core, and this may have been obtained if necessary by untying the yarn (separating the filaments by means known to those skilled in the art) before impregnating it with the composition. This yarn may in particular comprise, or be coated with, the hardened (dried and / or crosslinked) adhesive composition.

[0076] The invention also relates to a cord coated and / or impregnated with an adhesive composition according to the invention. This cord may in particular comprise, or be coated with, the hardened (dried and / or crosslinked) adhesive composition.

[0077] The cable may be formed from at least two threads not coated or impregnated with the adhesive composition, generally each thread is twisted, then the threads are cabled (assembled together and twisted in the opposite direction to the twisting of the elementary threads), then the cable is impregnated with the adhesive composition, which is hardened after application.

[0078] The cable can also be formed from the assembly of at least two threads coated or impregnated with the adhesive composition, generally each thread is twisted after solidification of the composition, and then the threads are cabled (assembled together and twisted in the opposite direction to the twisting of the elementary threads); it is then possible to provide for a coating of the cable with other treatments ("overcoat" or "topcoat"), and its drying.

[0079] The invention also relates to a textile structure formed from the assembly of threads by known techniques such as weaving or by gluing or welding in the case of grids. These textile structures are coated or impregnated with the composition of the invention, and the invention covers these textile structures coated with the hardened adhesive composition.

[0080] The adhesive compositions can be applied to textiles within the meaning of the invention by the methods used for RFL. Firstly, impregnation will be retained, by direct dipping or by means of a licking roller.

[0081] The invention also relates to an article or part made of rubber (or comprising a part made of rubber), comprising at least one reinforcing textile, in particular thread, cable and / or textile structure, according to the invention. This reinforcing textile may in particular be applied to the surface of the article or part and / or integrated inside the article or part.

[0082] As stated, rubber is a vulcanizable formulation based on natural or synthetic elastomers, such as vulcanized (crosslinked) natural rubber (NR or polyisoprene), or a vulcanized (crosslinked) synthetic rubber.Examples of synthetic rubbers include: polybutadiene (BR), polyurethane (AU or EU), polychloroprene (CR), silicone (VMQ, PVMQ) and fluorosilicone (FVMQ), ethylene-propylene-diene monomer (EPDM), butadiene-acrylonitrile copolymers (NBR for nitrile butadiene rubber), hydrogenated butadiene-acrylonitrile copolymers (HNBR), styrene / butadiene copolymer (SBR), epichlorohydrin (ECO or CO), butyl (IIR), bromobutyl (BIIR), chlorobutyl (CIIR), chlorinated polyethylenes (CM), chlorosulfonated polyethylenes (CSM), carboxylated nitrile butadiene acrylonitrile (XNBR), ethylene-methyl acrylate copolymers (AEM), ethylene-vinyl acetate copolymers (EVM and EVA), polyacrylates (ACM), fluorinated rubbers (FKM), perfluorinated rubbers (FFKM).

[0083] A rubber may also be a vulcanizable formulation based on mixtures or blends of such elastomeric gums.

[0084] The rubber can also be a thermoplastic-based formulation elastomers (so-called “physically crosslinked” elastomers such as SBS, styrene-butadiene-styrene block).

[0085] The invention relates in particular to an article or part made of elastomer or rubber comprising, embedded in its mass of elastomer or rubber, a reinforcing textile adhered according to the invention, for example one or more threads, individual or cabled or even assembled into textile structures, or several of these categories.

[0086] By "adhered" is meant in particular that the reinforcing textile comprises or is coated with the hardened (dried and / or crosslinked) adhesive composition.

[0087] The invention also relates to an article or part made of elastomer or rubber comprising, glued to at least one surface of this elastomer or rubber material, an adhered textile structure according to the invention.

[0088] The invention also relates to an article or part made of elastomer or rubber comprising, embedded in its mass of elastomer or rubber, one or more threads, individual or cabled or even assembled into textile structures, or several of these categories, and further comprising, glued to at least one surface of this elastomer or rubber material, a textile structure according to the invention, these reinforcing textiles being adhered in accordance with the invention.

[0089] As articles, the following articles may be cited, without being exhaustive, which may incorporate at least one adhered reinforcing textile according to the invention, in particular thread, cable or textile structure treated with the adhesion composition of the invention, applied to the surface of the article to which it adheres and / or integrated inside the elastomer material of the article:

[0090] - Belts, in particular transmission belts, synchronous belts, conveyor belts, elevator belts, trapezoidal belts. The belts may comprise wires or cords embedded in the mass of elastomer or rubber. They may also comprise, instead of or in addition to the wires and cords, a textile structure, in particular a fabric, adhering on the surface, for example on the back in the transmission belt, and on the back and the notching for the timing belt - Flexible or rigid hoses, including brake hoses (comprising a braided, single or double braided textile structure), hoses, industrial hoses (comprising a wrapped or spiraled textile structure, i.e. manufactured by wrapping or spiraling), including oil and gas hoses, hoses (knitted textile structure). Braiding, spiraling, knitting is generally carried out during the implementation of the hose by extrusion. - Specialty items: air springs, kinetic coupling discs, pipe plugs, compensation joints. - Tires: especially heavy goods vehicles and racing tires.

[0091] As examples of rubber composition for these articles: transmission belt: based on EPDM or CR; synchronous belts: based on HNBR and CR; Hoses: based on SBR, or EPDM, or an NBR / PVC blend, or epichlorohydrin, or butyl; Airspring: based on CR; kinetic discs: based on CR or NR; tires: thick part comprising several mixtures, based on NR, BR or SBR

[0092] The invention has the advantage of being integrated into the recovery of non-food renewable raw materials. It allows the recovery of lignin, currently a waste product from the wood and paper industry. This compound is perfectly harmless, has a low cost and high performance. Its use does not compete with the food market and is not subject to regulations on chemical products. It is an agro-resource.

[0093] The invention will now be described in more detail using embodiments taken as non-limiting examples.

[0094] Part I Preparation of formula comprising a lignosulfonate salt and an epoxy hardener (two-component example).

[0095] The phenomenon of crosslinking or "curing" of a thermosetting material, i.e. the formation of a three-dimensional covalent network resulting in a reaction product, is accompanied by a release of heat. Thus, the differential scanning calorimeter (DSC) is conventionally used to characterize the crosslinking of a thermosetting material. This is accomplished by subjecting an uncured thermosetting material to a controlled temperature ramp followed by analysis of the location, size and shape of the resulting exothermic peak.

[0096] A few grams of sodium lignosulfonate (Arbo NI8; Tembec N18) and an epoxy hardener (1,4 butanediol diglycidyl ether) are homogenized for 2 minutes in an aluminum cup under a hood at room temperature. The mass ratio of lignosulfonate salt / epoxy hardener is precisely 1. Then a few milligrams of this composition are sealed in an aluminum crucible with a diameter of 43 mm and a depth of 12 mm. The sample is then placed in a METTLER TOLEDO DSC 3+ STARe SYSTEM equipment and subjected to a temperature ramp from 25 to 300°C, at 10°C per minute, under a nitrogen flow of 80 ml per minute. The total enthalpy change that the sample undergoes is recorded by integrating the surface under the exothermic peak using the STAR SW 14.00 software, then normalized in Jg *.The cooking temperature in °C, where the crosslinking kinetics are strongest, is measured at the maximum peak (peakmax) of the exothermic peak with an accuracy of + / - 1°C.

[0097] The same process is applied to produce other compositions containing 2,2-bis(4-hydroxyphenyl) propane diglycidyl ether; diglycidyl 1,2-cyclohexanedicarboxylate; 3,4-epoxycyclohexylmethyl 3,4 epoxycyclohexanecar-boxylate; 1,6 hexanediol diglycidyl ether; glycerol diglycidyl ether; glycerol tri-glycidyl ether; mixture of glycerol diglycidyl ether and glycerol triglycidyl ether marketed by Raschig under the reference GE100; novolac type epoxy resin marketed by HUNTSMAN under the reference Araldite® PZ 323.

[0098] The same process is applied to produce other samples containing only sodium lignosulfonate.

[0099] The same process is applied to produce other samples containing only the epoxy hardener.

[0100] [Tables] Exothermic variation (in % vs. lignosulfonate salt control) Ratio Lignosulfonate salt / Hardener 1 0 1,4 butanedial diglycidyl ether 1129 0 2,2-bis(4-hydroxyphenyl) propane diglycidyl ether 1079 0 diglycidyl 1,2-cyclohexanedicarboxylate 1058 0 3,4-epoxycyclohexylmethyl 3,4 epoxy cyclohexanecarboxylate 957 0 1,6 hexanediol diglycidyl ether 1134 0 glycerol diglycidyl ether 1199 0 glycerol triglycidyl ether 1100 0 GE100 993 33 Araldite® PZ 323 595 0

[0101] The variation in exothermic energy measured for the control sample containing only lignosulfonate is normalized to 100%.

[0102] The compositions containing only an epoxy hardener (lignosulfonate salt / hardener mass ratio of 0) exhibit zero or low exothermic variations, between 0 and 33% compared to the lignosulfonate salt control.

[0103] The compositions containing sodium lignosulfonate and an epoxy hardener (lignosulfonate salt / hardener mass ratio of 1) exhibit variations in exothermic energies of between 595 and 1199% compared to the lignosulfonate salt control. This strong variation in exotherm compared to the control is characterized characteristic of the phenomenon of crosslinking or "cooking" of a thermosetting material. The role of the epoxy hardener on the lignosulfonate is clearly apparent here.

[0104] Examples II: Part Examples of preparation of adhesive formula

[0105] The definitions and methods of measurement or control described in this part apply generally to the application, unless otherwise indicated.

[0106] The dry extract (or mass concentration) of the preparations is defined as the percentage of residual dry matter after evaporation of the volatile matter (water, solvent) according to a defined drying method. The analysis is carried out using a desiccator balance, on a wet sample taken with a mass mech= between 2 and 5 grams. The sample is placed in a previously tared aluminum cup containing a binder-free fiberglass filter, with a surface density of 52 g.m2 and a threshold of 1.6 pm. The whole is then subjected to a temperature of 120 °C until the mass is completely stabilized. The result is expressed in %.

[0107] The viscosity of the preparation is measured at 23°C using a Brookfield viscometer. Unless otherwise stated, the measurement is carried out using a ULA (Ultra Low Viscosity Adaptor) module and a spindle no. 1 (low viscosity system) at a speed of 60 rpm (revolutions per minute).

[0108] The pH of the aqueous preparations is measured using a METLER 340 pH meter, calibrated for measurements in basic media using buffer solutions. A glass electrode and a 3M KC1 electrolyte are used.

[0109] Unless otherwise stated, the water used to make the preparations is osmosis quality water, with a residual conductivity of less than 70pS / cm.

[0110] Example C.II-1: Preparation of an adhesive based on sodium lignosulfonate and an epoxy hardener

[0111] In a first embodiment of the invention, 64.2g of sodium lignosulfonate (Arbo N18; Tembec) are dissolved with stirring in 1184g of water. 2.5g of a 10% by mass sodium hydroxide solution are then added to the solution, which is kept stirring for 10 minutes to allow complete solubilization. This solution is added with stirring to 983g of a styrene-butadiene-vinylpyridine copolymer latex (VPSBR). The whole is kept stirring (150 rpm) during the hardener preparation phase.

[0112] 35g of GE100 are stirred vigorously (300rpm) with 230 grams of water. This The solution is added to the lignosulfonate and latex preparation. Stirring is continued for a few minutes until completely homogenized.

[0113] The preparation has a pH of 10.8, a dry extract of 19.43% and a viscosity of 2.45 mPa.s.

[0114] The same process was applied to produce 2 other compositions by varying the following parameters:

[0115] Mass ratio of hardener / lignosulfonate salt: from 56% to 116%

[0116] Mass ratio [lignosulfonate salt + hardener] / latex: from 18% to 21%

[0117] % by mass of dry latex in the composition: from 80 to 84%.

[0118] In total, 3 compositions were produced.

[0119] Example C.II-2: Second method of preparing a sodium lignosulfonate adhesive and an epoxy hardener

[0120] In a second embodiment of the invention, 34.8g of sodium lignosulfonate are introduced into a container and 782g of water are gradually added. The solution is stirred at 200rpm. 20g of a 10% by mass sodium hydroxide solution and 100.7g of 20% by mass ammonia are then successively added to the preparation with stirring. The mixture is stirred at 200rpm for 10 minutes.

[0121] The basic sodium lignosulfonate solution is added with stirring to a latex preparation of a styrene-butadiene copolymer (wet latex SBR; 946g) and to 157g of previously homogenized water.

[0122] 75.5g of GE100 are stirred vigorously (300rpm) and 383.75 grams of water are added. are added. This emulsion is immediately added with stirring to the lignosulfonate and latex preparation. Stirring is continued for a few minutes until completely homogenized.

[0123] The preparation has a pH of 12.2, a dry extract of 19.9% and a viscosity of 2.7 mPa.s.

[0124] The same process was applied to produce another composition by varying the following parameters:

[0125] Mass ratio of hardener / lignosulfonate salt: from 217% to 218%.

[0126] Mass ratio [lignosulfonate salt + hardener] / latex: from 21% to 29%.

[0127] % by mass of dry latex in the composition: from 78% to 82%.

[0128] In total, 2 compositions were produced.

[0129] Example C.II-3: Third method of preparing an adhesive based on sodium lignosulfonate and an epoxy hardener

[0130] In a third method of preparation of the invention, a basic solution of sodium lignosulfonate is prepared by dissolving, with stirring, 19g of sodium lignosulfonate in 955g of water and adding 19g of a 10% by mass sodium hydroxide solution. The preparation is left stirring at 200rpm for 10 minutes to allow complete solubilization.

[0131] A basic latex dispersion is prepared by introducing 167g of water into a container, which is then stirred at 200rpm. 1049g of a styrene-butadiene copolymer latex (SBR), then 25g of a 20% by mass ammonia solution are then introduced successively. The basic lignosulfonate solution is then added with stirring to the latex dispersion.

[0132] 49g of GE 100 are put under vigorous stirring (300rpm) and 216 grams of water are added added. This solution is immediately added with stirring to the preparation of li-gnosulfonate and latex. Stirring is continued for a few minutes until completely homogenized.

[0133] The preparation has a pH of 12.25, a dry extract of 18.33% and a viscosity of 2.25 mPa.s.

[0134] The same process was applied to produce 2 other compositions by varying the following parameters:

[0135] Mass ratio of hardener / lignosulfonate salt: from 255% to 516%

[0136] Mass ratio [lignosulfonate salt + hardener] / latex: from 16% to 46%

[0137] % by mass of dry latex in the composition: from 68% to 86%.

[0138] In total, 3 compositions were produced.

[0139] Example C.II-4: Fourth method of preparing an adhesive based on potassium lignosulfonate and an epoxy hardener.

[0140] In this method of preparation, 94.5g of an aqueous solution of potassium lignosulfonate and 63.7g of GE100 are mixed. 1794.8g of water are then poured onto the mixture with vigorous stirring. 33g of a 10% by mass sodium hydroxide solution and 166.6g of a 20% by mass ammonia solution are then successively added to the preparation with stirring. The mixture is left stirring for 10 minutes, then added with stirring to a chloroprene latex (CR wet latex; 1004g) in water (176g).

[0141] The preparation has a pH of 12.69, a dry extract of 19.58% and a viscosity of 2.45 mPa.s.

[0142] The same process was applied to produce 2 other compositions by varying the following parameters:

[0143] Mass ratio of hardener / lignosulfonate salt: from 33% to 134%

[0144] Mass ratio [lignosulfonate salt + hardener / latex]: from 20% to 47%

[0145] % by mass of dry latex in the composition: from 65% to 79%.

[0146] In total, 3 compositions were produced.

[0147] Example C.II-5: Fifth method of preparing an adhesive based on potassium lignosulfonate and an epoxy hardener

[0148] In this method of preparation, 94.5g of an aqueous solution of potassium lignosulfonate and 63.7g of GE100 are mixed. 1794.8g of water are then poured onto the mixture with vigorous stirring. 33g of a 10% by mass sodium hydroxide solution and 166.6g of a 20% by mass ammonia solution are then successively added to the preparation with stirring. The mixture is left stirring for 10 minutes, then added with stirring to a dispersion of chloroprene latex (CR wet latex; 1004g) in water (176g).

[0149] 1306g of this preparation are taken and diluted with stirring in 996g of water. 36g of an aqueous dispersion of zinc oxide at 55% by mass, 78g of an aqueous dispersion of carbon black at 35% by mass and 83g of an adhesion promoter (blocked isocyanate) are then successively added with moderate stirring.

[0150] The preparation has a pH of 12.32, a dry extract of 14.1% and a viscosity of 1.95 mPa.s.

[0151] The same process was applied to produce 2 other compositions by varying the following parameters:

[0152] Mass ratio of hardener / lignosulfonate salt: from 33% to 135%

[0153] Mass ratio [lignosulfonate salt + hardener] / latex: from 20% to 47%

[0154] % by mass of dry latex in the composition: from 48% to 59%

[0155] In total, 3 compositions were produced.

[0156] The compositions of these examples are used in the treatment part of the reinforcing textile. Part III - Treatment of the reinforcing textile

[0157] The definitions and methods of measurement or control described in this part apply generally to the application, unless otherwise indicated. The mechanical characteristics of the treated textiles, such as tensile strength, elongation at break, shrinkage, temperature shrinkage, contraction, shrinkage force, linear weight, dip pick-up (DPU), stiffness, etc., are measured according to the standards in force in the textile industry. In the context of the present invention, it has been verified that the new treatments do not result in any modification of these properties, compared to the standard RFL.

[0158] The adhesive preparations of the invention are subject to an evaluation of their adhesion performance. After coating the textile, it is deposited within an unvulcanized rubber matrix, so that the surface of the textile in contact with the rubber remains free of any pollution. The matrix containing the textile is then vulcanized by compression, according to temperature, time and pressure conditions specific to each rubber. The textile + vulcanized matrix assembly forms an adhesion test piece.

[0159] Adhesion test pieces can take several forms, described in different international standards, such as for example the ISO 36:2017 standard. The test pieces, and by extension the test carried out to determine adhesion, are commonly known to those skilled in the art under names such as Test-T (“pull-out test”, ASTM D2229-04), Test-H (according to the NF ISO 4647 or ASTM D4776-04 standard), peeling (peel-test), etc. The test is then carried out by stressing the test piece until the interfacial contact zone is destroyed, the textile is torn off, or the rubber matrix is torn. The adhesion is then evaluated according to criteria such as the appearance of the textile at break, the maximum adhesion force, the average tearing force, possibly related to the thickness of the test piece.

[0160] General information on impregnation processes

[0161] Generally, the textile impregnation process is carried out by dipping in tanks containing the adhesive preparations. A diagram of such a process is illustrated in Gomes A., Nabih N., Kramer T, Adhesion activation of tire textiles by resorcinol formaldehyde free coatings, Rubber World, March 2016.

[0162] The reel(s) of untreated yarns, ropes and cables may be positioned on a creel at the line inlet. An accumulator system may optionally be used. The yarns, ropes and cables may undergo either direct dipping in a tank or impregnation by a licking roller, for the application of the adhesion composition. After dipping or impregnation, the excess wet preparation is preferably removed, for example by pressing (furling), suction or by foams.

[0163] The adhesion composition is then dried and / or crosslinked. The coated impregnated textile can then be passed through an oven to allow the adhesion composition to dry and crosslink. After leaving an oven, the textile can again undergo an impregnation step, then a passage through an oven, these steps being able to be repeated, in particular up to a total of 4 impregnations (2, 3 or 4). At the end of the line, the threads, ropes or cables can be received on winders.

[0164] In another impregnation method, particularly suitable for mineral fibers (glass, basalt, carbon, etc.), a stripping system composed of a comb and / or “pigtails” can be used at the creel outlet. It allows maximum opening of the multifilament yarn, to promote strong impregnation. After the impregnation and drying and / or crosslinking steps, the yarn is then twisted in line. Cabling is preferably carried out on an already treated yarn. Additional treatments can be carried out on the cables thus formed.

[0165] In the various processes, the speeds can range from 1 m / min to 150 m / min, the oven temperatures from 30°C to 350°C, more specifically from 100 to 300°C, and even more specifically from 140 to 220°C. Mechanical tension can also be applied to the textile. Unless otherwise stated, in the following examples, the textiles were treated with the adhesion compositions which are the subject of the invention under conditions identical to those applied during treatment with an RFL.

[0166] Example III-1: Treated polyamide 4-6 reinforcement for belts.

[0167] In an example of preparation of the invention, the inventors have endeavored to present a solution which can be used as reinforcement in assemblies such as transmission belts or conveyor belts.

[0168] For this, a PA 4-6 cord of 470 / 5x3 dtex (100 / 125) construction was constructed by successive stages of twisting, then cabling. The cord obtained was treated by a first impregnation in a solution of methylene diphenyl diisocyanate in toluene, then subjected to drying and heat-setting in an oven. The cord was then impregnated in a tank containing the adhesive of the invention, at a mass concentration of dry matter of 20%, instead of the RFL treatment usually applied. The different yarns impregnated with the different adhesives obtained were evaluated for adhesion to a mixture based on EPDM (ethylene-propylene-diene monomer) accelerated with peroxide. The test pieces were produced by compression molding. A yarn impregnated with RFL, produced under the same conditions, made it possible to obtain the control adhesion values.The adhesion values obtained are presented in Table 2, and expressed as % adhesion compared to the adhesion obtained with the control RFL wire.

[0169] Example III-2: Treated glass reinforcement for profiles,

[0170] In an example of preparation of the invention, the inventors have endeavored to present an invention which can be used as reinforcement in profiles and joints, such as window or door joints. Such reinforcements are made from glass yarn containing a size with which the adhesive composition must be compatible.

[0171] For this, several E-glass yarns with a 136tex count underwent unraveling and impregnation in the tank containing the adhesive of the invention, instead of the RFL. In this example, adhesives with a mass concentration of 20% were evaluated. The impregnated yarns were subjected to drying and heat-setting in an oven. Upon leaving the oven, the yarns underwent a twisting operation giving them a twist of 135 turns / meter in the Z direction. Three impregnated twists were then cabled together in a direction and at a level of 135 S. The different yarns impregnated with the different adhesives obtained were evaluated for adhesion to an EPDM rubber compound conventionally implemented by extrusion. The test pieces were produced by compression molding. A yarn impregnated with RFL, produced under the same conditions, made it possible to obtain the control adhesion values.The adhesion values obtained are presented in Table 2, and expressed as % adhesion compared to the adhesion obtained with the control RFL wire.

[0172] Example III-3: Treated polyethylene terephthalate reinforcement for pipes,

[0173] In another example of preparation of the invention, the inventors have endeavored to present a solution which can be used as a reinforcement, braided, spiraled, covered or knitted into a brake hose.

[0174] Example III-3 (a): For this, a 90 Z twist was applied to a polyethylene terephthalate (PET) yarn with a count of 1100 dtex. The yarn obtained was treated by impregnation in the adhesive that is the subject of the invention, then by heat-setting in an oven. The adhesives used in this example have a dry matter concentration of 20%. The different yarns impregnated with the adhesive were evaluated for adhesion to a peroxide-accelerated EPDM rubber mixture conventionally used in brake pipes. The test pieces were produced by compression molding. A yarn impregnated with RFL, produced under the same conditions, made it possible to obtain the control adhesion values. The values obtained are presented in Table 2, and expressed as % adhesion relative to the adhesion obtained with the control RFL yarn.

[0175] Example III-3 (b): In another example, a cord of 830 / 2x3 dtex construction was constructed by successive stages of twisting, then cabling. The resulting cord was treated by a first impregnation in a solution of methylene diphenyl dii-isocyanate in toluene, then subjected to drying and heat-setting in an oven. The adhesives used in this example have a dry matter concentration of 20%. The different yarns impregnated with the adhesive were evaluated for adhesion to a CR-based rubber compound. The test pieces were produced by compression molding. A yarn impregnated with RFL, produced under the same conditions, made it possible to obtain the control adhesion values. The values obtained are presented in Table 2, and expressed as % adhesion relative to the adhesion obtained with the control RFL yarn.

[0176] [Tables 2] Adhesive compositions C. II-l C. II-2 C. II-3 C. II-4 Hardener Epoxy GE 100 XXXX Lignosulfonate Sodium lignosulfonate XXX Potassium lignosulfonate X Latex VP-SBR X SBR XX CR III-l (PA 4-6) 89 to 98 Example III-2 (E glass) 72 to 77 Example III-3 (a) (PET) 131 to 155 Example III-3 (b) (PET) 100 to 115

[0177] The Polyamide 4-6 cord of Example III-1 treated with the different adhesives of Example C.IL1 showed satisfactory levels of adhesion with EPDM in comparison with the impregnated control yarn RFL. The levels of adhesion obtained, as well as the observation of the fracture surfaces, show that the adhesives evaluated are compatible with the first impregnation applied to the textile.

[0178] The E-glass cord of Example III-2 treated with the different adhesives of Example C.IL2 showed satisfactory adhesion levels with respect to EPDM in comparison with the impregnated control yarn RFL. The adhesion levels obtained, as well as the observation of the fracture surfaces, show that the adhesives evaluated are compatible with glass sizing. In addition, the glass strands thus treated showed no visual damage, nor did they cause excessive fouling on the processing lines. This demonstrates the ability of the adhesives evaluated to provide properties identical to RFL, including mechanical protection properties.

[0179] The PET yarn of Example III-3 (a), treated with the different adhesives of each of Example C. 11-3 showed higher levels of adhesion to EPDM than the RFL impregnated control yarn. The PET yarn of Example III-3 (b), treated with the different adhesives of each of Example C. 11-4 showed satisfactory levels of adhesion to the CR mixture than the RFL impregnated control yarn.

[0180] In conclusion, the results of these different tests clearly demonstrate that the adhesive compositions according to the invention constitute a very interesting alternative to the use of conventional RFL adhesion solutions containing formaldehyde and resorcinol.

Claims

Claims

1. A textile adhesive composition comprising a lignosulfonate salt, an epoxy hardener of said salt comprising at least two epoxy units, and an elastomer latex, the lignosulfonate salt and the epoxy hardener being intended to react together to form a reaction product.

2. The composition of claim 1, wherein the lignosulfonate salt is a sodium, potassium, magnesium, ammonium or calcium lignosulfonate.

3. Composition according to claim 1 or 2, in which the hardener is chosen from diglycidyl or polyglycidyl ethers of aliphatic polyols, diglycidyl or polyglycidyl ethers of polyfunctional phenols, polyglycidyl ethers of condensation products of phenols with formaldehyde obtained under acidic conditions, di- or polyglycidyl esters of aliphatic or aromatic polycarboxylic acids, compounds with epoxy-cyclohexyl groups, polyepoxide compounds resulting from the epoxidation of an olefinically unsaturated compound, and mixtures thereof.

4. Composition according to claim 3, wherein the hardener is selected from the following compounds: 1,4 butanediol diglycidyl ether, 2,2-bis(4-hydroxyphenyl) propane diglycidyl ether, Diglycidyl 1,2-cyclohexanedicarboxylate, 3,4-epoxycyclohexylmethyl 3,4 epoxy-cyclohexanecarboxylate, 1,6 hexanediol diglycidyl ether, Glycerol diglycidyl ether, Glycerol triglycidyl ether, mixture of glycerol diglycidyl ether and glycerol triglycidyl ether, novolak type epoxy resins, and mixtures thereof.

5. A composition according to any one of claims 1 to 4, comprising a carboxylated acrylonitrile / butadiene copolymer latex (XNBR), a hydrogenated acrylonitrile / butadiene latex (HNBR), a chlorosulfonated polyethylene latex (CSM), a styrene-butadiene-vinylpyridine copolymer latex (VPSBR), a styrene / butadiene copolymer latex (SBR), an acrylonitrile / butadiene copolymer latex (NBR), a polybutadiene latex (BR), a chlorobutadiene latex (CR), a natural rubber latex (NR), a polyurethane latex, or a mixture of at least two of them.

6. Composition according to any one of claims 1 to 5, in which the mass content of dry matter of the composition can be including in particular between approximately 2 and approximately 38%, in particular between approximately 4 and approximately 30%, more particularly between approximately 7 and approximately 25%.

7. A composition according to any one of claims 1 to 6, comprising from about 40 to about 95%, preferably from about 55 to about 90% by weight of elastomer relative to the composition.

8. Composition according to any one of claims 1 to 7, in which the mass ratio of hardener / lignosulfonate salt is between about 0.01 and about 5, more particularly between about 0.03 and about 1, typically between about 0.05 and about 0.

5.

9. Composition according to any one of claims 1 to 8, in which the mass ratio [hardener + lignosulfonate salt] / latex is between approximately 0.05 and approximately 0.6; more particularly between approximately 0.15 and approximately 0.

5.

10. A composition according to any one of claims 1 to 9, having a neutral or basic pH, in particular a pH of between about 7 and about 13, in particular between about 9 and about 13.

11. A kit for producing an adhesive composition according to any one of claims 1 to 10, comprising a first composition comprising a lignosulfonate salt and an elastomer latex, and a second composition comprising an epoxy hardener of the lignosulfonate salt.

12. Use of a composition or kit according to any one of the preceding claims, for conferring adhesion properties to a reinforcing textile, with respect to a rubber.

13. Reinforcing textile, in particular yarn, cable or textile structure, at least partially coated and / or impregnated with an adhesion composition according to any one of claims 1 to 10.

14. Part made of rubber or comprising rubber, in which the rubber comprises at least one reinforcing textile according to the preceding claim, on the surface and / or integrated inside the rubber.