Textile article suitable for recycling and method for producing said article

Abstract

A textile article comprising: at least one fiber substrate, at least one finishing compound distributed over at least one portion of the fiber substrate, wherein the finishing compound comprises: a polymeric component suited to define at least one reversible bond with the fiber substrate; a cross-linking agent suited to define at least one irreversible bond with the fiber substrate and / or with the polymeric component; and wherein the cross-linking agent is chemically compatible with the polymeric component and / or with the fiber substrate to make a lattice-type structure.

Description

TEXTILE ARTICLE SUITABLE FOR RECYCLING AND METHOD FOR PRODUCINGSAID ARTICLEDESCRIPTIONField of application of the invention

[0001] This invention fits within the technical field of the design and manufacture of textiles and related products, and relates to a particularly innovative textile article that can easily be recycled.

[0002] This invention also relates to a method for manufacturing textile articles that can easily be recycled.State of the art

[0003] As is known, the manufacture of goods and articles requires considerable consumption of resources and raw materials.

[0004] Such consumption relates not only to the production chain (whose purpose, of course, is to process raw materials in order to obtain the final product), but increasingly also to all those activities associated with the disposal of the product.

[0005] In fact, it is precisely during the disposal of a product that the deconstruction of the complex article takes place in order to obtain the greatest possible quantity of raw materials that were originally used to make the product.

[0006] It is quite rare to come across totally circular recycling processes, i.e. based on the fact that disposal yields all the virgin materials originally used.

[0007] Recycling processes of this type, in fact, allow for the complete reversibility of the product over a large number of production (or rather, re-production) cycles of the same article.

[0008] More generally, a product can be designed and manufactured in a way that allows it to be partially recycled.

[0009] In this case, in fact, through disposal and recycling, it is possible to recover all the raw materials originally used to make the product itself.

[0010] It is quite clear that it is particularly difficult to design and manufacture products from which a large percentage of virgin raw materials can be recovered after disposal.

[0011] After all, it is common knowledge that the mass consumption of resources and virgin raw materials has a significant impact on the environment.

[0012] In recent years, more and more technical sectors are modifying their productionand product development processes in order to implement, as much as possible, a green and sustainable economic vision through which it is possible to at least limit the consumption of virgin raw materials by reusing raw materials that have been recovered from a disposal process.

[0013] In the current context, therefore, there is a strong social, economic and technological drive to change current production habits and techniques in order to generate products that can move closer and closer to the logic of complete circularity, so that they can be substantially self-sustainable ecologically.

[0014] This profound change also affects the sector of textile articles and yarns in general, which are used in many practical applications (clothing, upholstery and furnishings, to name but a few examples).

[0015] In addition, the textile articles sector includes supply chains for the processing of raw materials that have always been particularly energy-intensive with a high environmental impact.

[0016] The fibers constituting these textile articles are generally treated with finishing compounds to give them specific chemical and physical or chromatic properties.

[0017] For example, the use of finishing compounds makes it possible to make the article fireproof (or otherwise resistant to flames or high temperatures), and / or hydrophobic or oleophobic, water or oil repellent or waterproof so as to make the article hostile to bacteria or parasites.

[0018] In most cases, the purpose of the finishing compound is to make the virgin fibers constituting the article resistant both to dry and wet rubbing and to household washing.

[0019] It is well known, in fact, that the washing of fabrics or textile articles in general is always performed using a detergent dissolved in hot water, typically having a temperature at least close to 40°C.

[0020] In addition, the fibers constituting the textile articles may undergo printing or dyeing (coloring) processes to give them the desired aesthetic features.

[0021] The tendency to subject even textile articles to a circular reuse process has led the industry to focus on the large amount of waste on the market due to the short life cycle associated with this type of product.

[0022] In fact, an attempt was made to reuse textile articles discarded by the market (or belonging to the so-called second-hand supply chains) in order to recover the base raw materials through fiber grinding or fraying processes.

[0023] Thanks to these mechanical processes, in fact, it is possible to recover a part of the fibers contained in them; these fibers can then be reintroduced into the supply chain so as to constitute a fraction of the base material that can be used to generate new articles or fabrics.

[0024] It is also worth mentioning that the fiber obtained from grinding or fraying processes can also be used again in technical fields other than textiles, e.g. as an insulating material inside insulation panels.

[0025] When a textile article that has previously undergone a finishing process (e.g. performed to make it fireproof, dyed and / or wash resistant) is to be recovered and recycled, the mechanical operations of grinding and fraying must be preceded by a step for removing the finish from the virgin textile fibers.

[0026] At present, the step of removing the finishing compound from the textile article subject to recycling does not always guarantee acceptable results.

[0027] The main drawback of this step, in fact, is that the composition of the finishing compound is chosen in such a way as to encourage permanent adhesion to the fibers.

[0028] This adhesion, therefore, is based on the establishment of very strong chemical bonds with the textile fibers; the nature of the latter is such that it is very difficult to separate the finishing elements from the fibers during the recycling process.

[0029] A further limitation of the textile articles containing finishing compounds currently available on the market lies in the fact that, if undergoing a recycling process, they require the execution of very energy-intensive processing steps whose purpose is to separate the finishing compound from the fibers of the textile article to be recycled.

[0030] Another limitation of these textile articles lies in the fact that recycling processes have to be set up using chemical solvents (referred to as “scouring agents”) that are potentially polluting and hazardous to human health.

[0031] In addition, textile articles containing finishing compounds currently available on the market are not very suitable for being reused in large parts, as the presence of the finishing drastically reduces the overall recycling efficiency and, therefore, only a fraction of the recovered fiber has similar features as those expected for a virgin fiber.

[0032] As a consequence, a large part of the fibers obtained as a result of the recycling of textile products subject to finishing are of poor quality or at least inferior to virgin textile fibers.

[0033] Finally, textile products that have undergone a finishing process require arecycling process that, in addition to having a big impact on the environment and having a limited yield, as mentioned above, is particularly costly financially.Description of the invention

[0034] This invention is intended to overcome the aforementioned technical drawbacks by providing a textile article in accordance with claim 1.

[0035] In particular, the main purpose of this invention is to provide a textile article that can easily be recycled, i.e. such that a large fraction of the textile fibers constituting the article itself can be fully recovered in a state similar to the virgin state.

[0036] In addition, another purpose of this invention is to provide a textile article from which it is possible to recycle almost all of the textile fibers composing it - in a state similar to the virgin state - even when this article has a finishing compound applied.

[0037] Another purpose of this invention is to provide a textile article suitable for recycling with a significantly reduced energy expenditure.

[0038] Another purpose of this invention is to provide a textile article that is suitable for recycling using solvents with a reduced impact on both human health and the environment.

[0039] Another purpose of this invention is to provide a textile article suitable for recycling using processing conducted at atmospheric pressure.

[0040] Another purpose of this invention is to provide a textile article that minimizes the presence of finishing compound residues between the fibers during recycling.

[0041] Another purpose of this invention is to provide a textile article suitable for recycling in an essentially circular manner through recycling processes with a low cost and low environmental impact.

[0042] Again, not the least important purpose of this invention is to provide a textile article suitable for recycling on a large scale, even when it is produced in large quantities.

[0043] These purposes, together with others that will be better clarified below, are achieved with a textile article of the type in accordance with claim 1.

[0044] Other purposes that will be better described below are achieved with a textile article in accordance with the dependent claims.

[0045] According to another aspect of this invention, there is a method for producing a textile article of the type in accordance with claim 10.

[0046] As will become clear later in this description, the method for producing a textile article suited to be easily recycled also has the advantages mentioned above.Detailed description of the invention

[0047] This invention relates to a textile article. In particular, as will be better clarified later in this description, the subject of this invention is a textile article particularly suitable for recycling.

[0048] This textile article has chemical and physical features that make it particularly well suited to being recycled according to a “circular” technique, i.e. a recycling process that, starting from the manufactured article this invention relates to, succeeds in recovering almost all the textile fibers it contains while keeping the features associated with them substantially similar to those possessed by virgin fibers that have not yet undergone any processing.

[0049] This invention applies to any type of textile article, i.e. both articles belonging to the category of “woven fabrics” and those belonging to the category of “non-woven fabrics”.

[0050] According to UNI EN ISO 9092, a non-woven fabric article can be defined as an engineered, primarily planar, assembly of fibers that has been given a designed level of structural integrity using physical and / or chemical means, excluding weaving, knitting or paper making.

[0051] It is therefore possible to apply the object of this invention to all known textile articles:- that come under the category of non-woven fabric products in accordance with the above-mentioned UNI standard;- that come under the category of textile products in general, i.e. textile products that do not come under the above-mentioned UNI standard.

[0052] This description preferably relates to a textile article of the stitch-bonded type, i.e. a fabric belonging to the hybrid-matrix, non-woven fabric family.

[0053] A stitch-bonded backing is generally used to make articles with common uses such as cushion covers, mattresses, carpets, etc. A more accurate definition of a stitch- bonded fabric is given later in the description.

[0054] However, it is implied that the article that this invention relates to may be different from the stitch-bonded non-woven fabric, as well as having a different use from that generally associated with the latter.

[0055] In general, the term “article” used in this context means any product made of textile material, obtained through the use of textile fibers of any kind (e.g. of hybrid origin,but not only).

[0056] More specifically, this textile article is advantageously manufactured from multiple fibers interwoven, or bonded or woven together.

[0057] The fibers can be, for example, natural (cotton, wool or the like) or synthetic (e.g. polyester or polypropylene, para-aramid) or even artificial (e.g. viscose and / or fireproof viscose).

[0058] In addition, these fibers may also be a combination of natural and synthetic fibers.

[0059] The combination of fibers used to make the textile article can be chosen to give it specific features for its use. Typically, fabrics can be produced entirely from synthetic fibers or entirely from virgin or recycled fibers. Alternatively, it is possible to use a mixed configuration made of artificial fibers that make the product more or less similar to a conventional fabric or more or less susceptible to receiving different types of finishing compounds (described in more detail later in this description). Conveniently, the article can be very flexible in its composition; for example, it is possible to use percentages of different types of fibers (e.g. 40% viscose and 60% polyester), as well as to create articles containing only a single type of fiber (e.g. 100% polyester, 100% viscose, etc.).

[0060] Merely by way of non-limiting example, reference will be made in the following to a stitch-bonded textile article made from polyester fibers, although, in accordance with the above, the article in question may be made from a fiber of any other material.

[0061] Conveniently, the textile article that this invention relates to comprises at least one fiber substrate.

[0062] The term "stitch-bonded' means a type of non-woven fabric known to people skilled in the art, which involves binding layers of base fibers (all arranged along an essentially longitudinal extension direction) by means of binding threads, arranged along an essentially transverse direction (analogous to warp threads).

[0063] Each binding thread defines a corresponding binding (or warp) line, suited to run across the entire width of the base fiber substrate (non-woven fabric).

[0064] In addition, the binding threads can be chosen from the range of natural polymer threads (e.g. cotton), synthetic polymer threads (e.g. polyester, polypropylene), or threads obtained by combining natural and synthetic materials.

[0065] Preferably but without imposing limits, the base fibers making up the substrate are suitably carded so that they are arranged substantially parallel to each other in the longitudinal extension direction.

[0066] The binding lines defined by the binding threads are preferably arranged transversally to the longitudinal extension direction so that they are substantially orthogonal to it.

[0067] Alternatively, the binding lines may be arranged obliquely to the longitudinal alignment direction of the base fibers, i.e. these lines may form an angle of a predetermined value with respect to the longitudinal direction.

[0068] For example, the angle between the binding lines and the longitudinal alignment direction of the fibers may be not less than 45°.

[0069] In the context of this invention, therefore, the term “transverse” used to define the extension direction of the binding lines can be interpreted as either a direction that is effectively perpendicular to the alignment direction, or any oblique direction that forms a given angle with the latter (the value of which is discretionary and depends on the type of article to be obtained).

[0070] In addition, the length of the binding stitches can range between 1 mm and 6 mm, preferably between 1.7 mm and 3 mm. The fineness of the binding stitches - i.e. the density of the stitches based on the thread count per inch - can preferably range between 7 and 22 threads (per inch). In this context, the expression “length of the binding stitches” relates to the length of a single stitch, i.e. the distance between one stop and the other of the frame.

[0071] Of course, the above-mentioned ranges - referring to the length of the binding stitches and the fineness of these - should be understood as illustrative but not limiting, since a textile article used in the context of this invention may possibly also include values other than those indicated.

[0072] The binding stitches are produced using continuous threads that are suitably processed during the creation step of the textile article in order to create series of continuous stitches to form binding lines (also known as warp lines), which extend along directions other than the alignment direction followed by the fibers that make up the article.

[0073] Conveniently, the binding stitches can be of the “chain” type, i.e. produced using appropriate machines to interweave the upper thread with the lower thread, forming a series of connected loops, similar to a chain, on the back of the fiber substrate.

[0074] In this way, each stitch is hooked to the previous one, thus ensuring that the resulting stitch-bonded textile article has a high degree of elasticity and strength.

[0075] The textile article according to the invention also comprises at least one finishing compound distributed over at least one portion of said fiber substrate.

[0076] In the context of this invention, the term “finishing compound” means any material or compound of materials distributed over the base fibers of the substrate in such a way as to facilitate at least partial coverage.

[0077] More specifically, the purpose of the finishing compound is to endow the article with one or more particular technical (chemical or physical) or aesthetic features.

[0078] For example, a finishing compound may be used to endow the article with a particular coloring or surface finish.

[0079] In particular, according to a first embodiment of the invention, the finishing compound may be distributed over the entire surface area defined by the base fiber substrate; in this case, therefore, the compound is distributed across all the fibers of the substrate for its entire extension.

[0080] In an additional embodiment of the invention, the finishing compound may be distributed over a limited portion of the substrate; in this case, there will be an area of the substrate over which the finishing compound has been distributed and a remaining area in which the finishing compound has not been distributed (and in which only the base fiber and possibly one or more binding lines are present).

[0081] The finishing compound can be applied to the textile article using multiple techniques, e.g. impregnation, or coating, or doctoring or even foaming. This list is not exhaustive, and the finishing compound may also be distributed on the textile article using other techniques not mentioned above.

[0082] In addition, the compound will only be able to adhere to (and thus coat) the outer surface of the fibers. Alternatively, during the application of the finishing compound on the substrate, this compound may also penetrate into the substrate and thus not define a single surface coating of the substrate. The degree of penetration of the finishing compound on the substrate may vary depending on the technique used to apply it.

[0083] Conveniently, the finishing compound may also have the purpose of endowing the article with a particular chemical or physical feature or property, for example:- making the article fireproof (or otherwise resistant to flames or high temperatures), and / or- making the article hydrophobic or oleophobic, or water or oil repellent or waterproof and / or- making the article hostile to parasites and bacterial cultures.

[0084] According to the invention, the finishing compound comprises at least one polymeric component suited to define at least one reversible bond with said fiber substrate.

[0085] The expression “reversible bond” used in the preceding paragraph is intended to refer to the multiple chemical bonds (molecular bonds) that the polymeric component establishes with the base fibers and which, by their nature, can be severed under particular conditions without causing any chemical or physical alteration to the base fiber.

[0086] The reversible bonds that can be created by the association of the polymeric component with the substrate fibers could, for example, be included in the following list:Van der Waals forces, creation of ionic bonds, hydrogen bridges

[0087] In addition, reversible bonds of the type mentioned above come under the category of weak bonds since they possess very low bonding energy, thus defining reversible bonds that can break relatively easily.

[0088] By way of example, the energy of the reversible bonds formed by the association of the polymeric component with the fibers defining the substrate is much lower than for covalent bonds, and ranges between 0.1 and 10 kcal / mol (compared to 80-100 kcal / mol required for covalent bonds).

[0089] In addition, the finishing compound comprises at least one cross-linking agent suitable for defining at least one irreversible bond with said fiber substrate and / or with said polymerizing agent.

[0090] The term “irreversible bond”, on the other hand, refers to the multiple chemical bonds (i.e. atomic bonds) that the cross-linking agent establishes with the base fibers and the polymeric component and, by their nature, cannot be removed except by altering the chemical or physical structure of the base fiber.

[0091] Conveniently, the irreversible bonds created by the interaction between the crosslinking agent and the fiber substrate can be chosen from the set comprising strong covalent bonds, metal-covalent bonds, etc.

[0092] Irreversible bonds are said to be strong and possess a high bonding energy (typically between 80-100 kcal / mol).

[0093] Moreover, the breaking of an irreversible bond is permanent and, therefore, sucha break generates a definitive change in the structure or function of the molecule previously involved with an irreversible bond.

[0094] In the context of this invention, the percentage of irreversible bonds formed by the cross-linking agent with the fibers that make up the substrate is relatively low; these bonds, in fact, serve to ensure the wash fastness of the article but, at the same time, allow them to be removed under atmospheric pressure to enable the article to be recycled.

[0095] The cross-linking agent of the finishing compound binds with said polymeric component and / or with said fiber substrate to produce an at least partially lattice structure.

[0096] Conveniently, the combination formed by the polymeric component and the cross-linking agent may constitute a resin or binder (in this context, resin and binder are used as synonyms); consequently, the finishing compound may comprise at least such a resin (i.e. comprise the polymeric component and the cross-linking agent). However, the finishing compound may comprise additional elements in addition to the resin. For example, the cross-linking agent may comprise a pigment, flame retardant compound, etc. in addition to the resin.

[0097] The finishing compound may firstly cross-link due to the fact that it comprises a resin that may not contain isocyanates in an initial form, but which cross-links due to the presence of chemical fractions owing to the low purity of the resin.

[0098] Alternatively, if the resin is pure, its constituent polymers can be functionalized by monomers that have the feature of possessing functional groups suitable for subsequent cross-linking - subsequent to application - which means the binder performs even better.

[0099] Examples of such monomers are N-Methylolacrylamide and, more generally, nitrogen-substituted acrylamides with hydroxyl-bearing chains; diacetone acrylamide; glycidyl methacrylate; acrylic, methacrylic or itaconic acids; etc., or by addition of isocyanates.

[0100] Such functional groups have the characteristic of lending themselves easily to a cross-linking reaction - with themselves or with other functional groups of other molecules appropriately.

[0101] In particular, the nature of the polymeric component makes it possible, following the distribution of the finishing compound on the fibers, to obtain a polymer chain capable of adhering to the base fiber by means of relatively weak, reversible bonds, i.e. subjectto being removed during the normal use of the textile article (e.g. as a result of the various washes it undergoes over time).

[0102] The polymers of the polymeric component may be in a solution of an appropriate solvent, in an aqueous dispersion or in bulk (i.e. the polymer constitutes the entirety of the resin (or binder).

[0103] In the case of polymers in solution, such polymers may have a medium to high molecular weight obtained by polycondensation of diols and isocyanates in a suitable solvent.

[0104] In the case of dispersion, on the other hand, the polymer will be prepared in a solvent and, due to the presence of water-like functional groups such as carboxylates, sulphates or sulphonates, etc. in the structure of the polymer itself, so-called “indirect” dispersion will occur and the simultaneous removal of the solvent.

[0105] Finally, in the case of bulk polymers, it is possible to use bulk polyurethanes, which can essentially be defined as low molecular weight polymers.

[0106] In other words, the polymeric component after being distributed on the base fibers of the substrate undergoes a polymerization process triggered at a predetermined trigger temperature.

[0107] On the other hand, the cross-linking agent allows the structure of the entire finishing compound to be modified by encouraging cross-links both between the polymers of the polymer chain and between these polymers and the base fibers.

[0108] These bonds, unlike those established by the polymeric component, are irreversible and, therefore, very strong.

[0109] Irreversible bonds are created to resist all the treatments that the textile article undergoes over time (e.g. washing, rubbing, temperature changes, etc.).

[0110] A predetermined combination of the polymeric component and the cross-linking agent facilitates the adhesion of the finishing compound to the fiber substrate exhibiting both of these features:Encouraging the formation of bonds suitable for resisting all the treatments expected during normal use of the textile article (washing, rubbing, deterioration, etc.) over time;Facilitating the almost complete removal of these bonds (and, thus, the complete removal of the finishing compound from the base fibers) when the article, at the end of its life cycle, undergoes one or more specific treatments carried out as partof recycling.

[0111] More specifically, the finishing compound according to the invention is, at the same time, firmly attached to the substrate but, under certain physical or chemical conditions, easily removable from the substrate.

[0112] In particular, the combination of the polymeric component and the crosslinking agent allowed the Applicant to obtain a textile article capable of maintaining the features given by the finishing compound over a long period of time, e.g. for dozens of washes, and at the same time to return to the state of raw fibers if subjected to a particular type of treatment performed during the recycling step of the article.

[0113] For example, a finishing compound can remain attached to the substrate without essentially losing its standard properties (e.g. mechanical adhesion of the finishing compound, color shade, temperature resistance, etc.) until such time as the article undergoes a specific recycling treatment, e.g. carried out using a particular solvent or mixture of solvents suitable for encouraging the detachment of almost all the bonds present between the base fiber substrate and the polymeric component / cross-linking agent.

[0114] A resin with a low residual value of cross-linking impurities and a low value of specially given cross-linking elements (i.e. added to the resin to make it cross-link, such as isocyanates) enables the textile recycling process to be optimized by immersion in a solution bath with a predetermined composition (called scouring, as will be better described below).

[0115] The finishing compound described here, therefore, ensures the extraction of the resin from the substrate through the scouring bath.

[0116] For example, a resin configured to polymerize while retaining a limited crosslinking capacity, compared to resins of the same use configured to polymerize and crosslink, will have lower mechanical strength and wash fastness (i.e. less ability to remain unchanged during washing without degrading or changing its chemical and physical properties).

[0117] Appropriate cross-linking agents can be selected to increase the wash fastness of the article treated with the finishing compound, as well as the mechanical strength of the substrate.

[0118] For example, by using the first resin listed above (configured to polymerize while retaining a limited cross-linking capacity), the textile article can withstand threewashes at 40°C; at the same time, this article can be scoured to make the substrate fiber recyclable. By using, on the other hand, the second resin mentioned above (configured to polymerize and cross-link), the resulting article can withstand ten washes at 60°C, gradually losing its ability to be recycled if subjected to scouring.

[0119] Conveniently, to achieve these results, it is necessary to functionalize the resins. In this case, it has been experimentally proven that the above results can be achieved using the following cross-linking percentages:

[0120] A high-purity resin will be of the exclusively polymerizable type; in order to achieve cross-linking it will be necessary to functionalize the polymers.

[0121] One example of a monomer suitable for functionalizing polymers (to achieve cross-linking) is N-Methylolacrylamide and, more generally, nitrogen-substituted acrylamides with hydroxyl-bearing chains; diacetone acrylamide; glycidyl methacrylate; acrylic, methacrylic or itaconic acids; etc., and, otherwise, isocyanates.

[0122] A melamine cross-linking agent and a blocked isocyanate (e.g. an aliphatic polyisocyanate pre-diluted in propylene carbonate) can be selected as the cross-linking agent.

[0123] Below are some examples of the weight and percentage of finishing compound on the fabric (here understood as fibrous substrate and binding lines):2.5 g / m2final on the fabric, i.e. 18% of a typical finishing compound on the fabric;2.3 g / m2final on the fabric, i.e. 15% of a typical finishing compound on the fabric;1 .9 g / m2final on the fabric, i.e. 7% of a typical finishing compound on the fabric;

[0124] Conveniently, this solvent may be aqueous.

[0125] In the jargon of the technical field of the invention, the step of removing the finishing compound from the substrate fibers is called “scouring”.

[0126] It should be emphasized that currently known finishing compounds (and part of the state of the art of this invention) are not removable from the fiber substrate without very invasive and energy-intensive treatments that, in any case, result in a degradationof the substrate fiber quality.

[0127] The use of a polymeric component and cross-linking agent, as well as the use of a finishing compound with a particular combination proportion by weight of the same, makes it possible to facilitate a treatment on the base fibers of the substrate that is able to maintain its properties basically the same overtime during the normal use of the article itself and to be easily removed through specific scouring treatments that do not require high energy for their implementation.

[0128] Conveniently, the textile article according to the invention can be used in an essentially circular production and recycling process.

[0129] The finishing compound of the textile article according to the invention is preferably removable from the fiber substrate by means of a scouring treatment that can be carried out at atmospheric pressure.

[0130] Advantageously, the polymeric component of the finishing compound is chosen from the following: acrylic-, vinyl-, styrene-acrylic- or vinyl-acrylic-based polymers.

[0131] Advantageously, the Applicant conducted numerous tests that established that the above-mentioned polymers, and in particular acrylic-based polymers, are easily removable when treated with an appropriate compound, such as sodium hydroxide (NaOH) and appropriate cationic and non-ionic surfactants.

[0132] Advantageously, said polymeric component of said finishing compound comprises a dispersion of polymeric particles having an average size between 10 nm and 10 pm.

[0133] The finishing compound preferably comprises polymers obtained by copolymerization.

[0134] In particular, the finishing compound comprises polymers obtained by radical copolymerization in aqueous emulsion.

[0135] The polymers of the finishing compound are preferably obtained by copolymerization of acrylic or methacrylic acid esters, in particular with carboxylic acids of 1 to 14 carbon atoms (linear or branched), styrene, vinyl acetate, vinyl esters of carboxylic acids with 3 to 14 carbon atoms (linear or branched), ethylene, vinyl chloride, nitriles of acrylic or methacrylic acid, amides of acrylic or methacrylic acid, acrylic, methacrylic and itaconic acids.

[0136] Advantageously, this finishing compound comprises polymers obtained byradical copolymerization in aqueous emulsion of monomers functionalized with crosslinking monomers.

[0137] More specifically, the polymer lattice is achieved by polymers bonded together by a cross-linking reaction.

[0138] Each polymer preferably comprises cross-linking monomers that enable crosslinking of the above-mentioned polymers to obtain cross-linked polymers.

[0139] In other words, the cross-linking agent may comprise at least one cross-linking monomer with at least one functional group configured to initiate a cross-linking reaction.

[0140] Examples of such monomers are N-Methylolacrylamide and, more generally, nitrogen-substituted acrylamides with hydroxyl-bearing chains; diacetone acrylamide; glycidyl methacrylate; acrylic, methacrylic or itaconic acids; etc.

[0141] In addition, the cross-linking agent may comprise at least one additional group of molecules configured to bind with said at least one cross-linking monomer to establish a cross-linking reaction.

[0142] In this case, therefore, the cross-linking agent of the finishing compound comprises the aforementioned additional group of molecules and, therefore, this crosslinking agent co-operates with the cross-linking monomer in order to regulate (improve) the cross-linking reaction.

[0143] In order to ensure correct cross-linking, it is necessary to control the transition speed by keeping the textile article, including the finishing compound, at a desired temperature (between 125°C and 170°C) and for a predetermined length of time (normally 160°C for 60 seconds).

[0144] Advantageously, this further group of molecules of said cross-linking agent comprises hydrazide of the adipic acid and / or at least one molecule comprising an isocyanate group.An example of a cross-linking agent including an isocyanate group is the resin with the commercial code EC 61.Conveniently, the finishing compound may also include, in addition to the above, a pigment suitable for giving the base fiber substrate a predetermined coloring.

[0145] In particular, this pigment can be chosen from the group of printing pigments.

[0146] By way of example, the quantity of pigment is given in the following tables; this quantity corresponds to the correct color / binder ratio if the textile article is printed on a printing press or on a stenter press.color / binder ratio when printing on printing presscolor / binder ratio when printing on stenter press

[0147] In addition, the finishing compound as described above is also able to guarantee sufficient wet and dry rubbing resistance to be able to withstand normal domestic washing, which is normally carried out at 40°C.

[0148] For the recycling of such a textile article, a predetermined chemical compound, as mentioned, known as a “scouring agent” can be applied, configured to break the bonds and, in particular, depolymerize the polymeric component of the finishing compound, so as to completely separate the polymeric component from the substrate fibers. In this way, the finishing compound is easily removed by normal washing.

[0149] The scouring also removes any pigment present in the finishing compound.

[0150] A method for producing the above-described article will be described later in this description. However, the following is an example of how such an article, which has reached the end of its life cycle and has been disposed of, can be used again in a recycling process in order to recover its constituent base fibers.

[0151] By way of example, the recycling process described below specifically targets a stitch-bonded textile article, i.e. a non-woven fabric made from polyester, viscose, natural or mixed fibers.

[0152] Firstly, during the recycling process, the textile article undergoes a step in which it is cut into strips.

[0153] By way of example only, the following is an experimental table correlating the average fiber length AL to the length L of the longest side.

[0154] Following this cut, the strips are immersed in a scouring bath containing solvents, preferably a water-based one.

[0155] In particular, the ratio of the mass of said strips to the mass of said bath ranges between 1 :7 and 1 :20.

[0156] Conveniently, the scouring bath can be made with 30% NaOH and suitable cationic and non-ionic surfactants.

[0157] The textile article is preferably kept in the scouring bath for between 20 and 50 minutes at a temperature ranging between 80 and 105°C.

[0158] At the end of the scouring treatment, a series of hot and / or cold washes are carried out until the finishing compound is completely detached from the base fiber substrate.

[0159] The above steps (soaking in the scouring agent for the prescribed times and at the prescribed temperatures and the series of successive washes) were developed to encourage the severing of the bonds that the polymeric component and the cross-linking agent, constituting the finishing compound, form with each other and with the base fibers.

[0160] Conveniently, the textile article of the type described above may include one or more accessories intended to adhere to or be mechanically bound with the fibers of base material treated with finishing compound.

[0161] For example, the accessory may consist of appropriate closure means (zips and / or Velcro strips and / or buttons or the like) suited to selectively allow access to the inside of a textile article defining an essentially bag-like shape or provided with pockets.

[0162] In addition, in order to make the recycling of the textile article thus produced quick and easy, the textile article described above may be provided with an appropriate label.

[0163] This label may contain different types of information associated with the production of the textile article. For example, this label may contain different types of technical information associated with:the type of base fiber; and / or the amount of such fiber; and / or the type of threads used to make the binding lines; and / or the features of any pigment used as a dye; and / or the partial or total composition of the finishing compound; and / or the operating conditions maintained during production of the manufactured article (temperature of application of the finishing compound, duration of such application, etc.)

[0164] This information is useful to outline the steps through which the textile article can be recycled at the end of its life cycle.

[0165] Therefore, the information on the label associated with the manufactured article allows the entirety of its constituent elements (or at least the base fibers) to be used and reused according to the dictates of the circular economy, through a rapid and relatively simple recycling process.

[0166] The label associated with the manufactured article may include, preferably, a radio frequency identification device, i.e. an RFID device, configured to contain the information set out above and / or to allow connection to an external information database.

[0167] Alternatively, the label associated with the manufactured article may include any electronic storage and / or data linking device that can contain or allow linking to the information associated with the manufacture of the textile article.

[0168] This invention also relates to a method for producing a textile article.

[0169] In particular, this method makes it possible to obtain a textile article of the type described above.

[0170] Accordingly, all of the above-described features of the textile article, taken individually or in any combination thereof, may also refer to the method for producing a textile article covered by this invention.

[0171] This method comprises at least the operational steps described below.

[0172] Preliminarily, the method involves a step a) of providing at least one base fiber substrate.

[0173] In addition, the method involves a step b) of the association of at least one finishing compound with the fiber substrate, in order to give the latter at least one predetermined chemical or physical feature (e.g. resistance to high temperatures, pigmentation, etc.).

[0174] According to the invention, the finishing compound comprises one polymeric component suitable for defining at least one reversible bond with said fiber substrate.

[0175] In addition, the finishing compound comprises one cross-linking agent suitable for defining at least one irreversible bond with said fiber substrate and / or with said polymeric component.

[0176] The cross-linking agent chemically reacts with the polymeric component and / or fiber substrate to create a lattice structure.

[0177] In this way, the combination of the polymeric component and the cross-linking agent makes it possible to obtain a textile article with a predetermined finish in which the bonds it has with the base fibers can be almost totally broken down by applying an appropriate recycling process.

[0178] More specifically, the finishing compound according to the invention is, at the same time, firmly attached to the substrate but, if subject to scouring steps using suitable solvents with certain physical or chemical features, is easily removable from the substrate.

[0179] Advantageously, the method includes, prior to said association step b), a step for the formation of said finishing compound.

[0180] This combining step can be performed by means of known finishing compound distribution techniques such as impregnation, coating, foaming or printing.

[0181] Step b) of forming the finishing compound involves at least the following operational sub-steps.

[0182] Preliminarily, the step for forming the finishing compound preferably involves a sub-step i) of providing a first group of monomers.

[0183] Preferably, a sub-step ii) of providing a second group of cross-linking monomers is also included.

[0184] The formation step b) also includes the sub-step Hi) of a functionalization reaction between the first group of monomers and said second group of cross-linking monomers.

[0185] The monomer of said first group is chemically bonded with at least one crosslinking monomer of the second group so as to obtain functionalized monomers.

[0186] The formation step also preferably includes a further sub-step iv) of copolymerization of said functionalized monomers obtained from said step Hi).

[0187] Following sub-step iv), it is possible to obtain a polymer lattice that is susceptibleto being bonded to the base fibers of the substrate.

[0188] In a preferred configuration of the production method (which, however, is not to be understood as limiting the invention), further steps are set out below: a step c) of arranging the fibers of base material along a direction essentially parallel to a longitudinal direction a step d) of inserting the binding lines arranged along a transverse (or oblique) direction with respect to the longitudinal direction along which the base fibers are arranged.

[0189] Conveniently, the binding lines can be produced using suitable binding threads suitable for defining multiple chain stitches that ensure an adequate hold of the fibers during the manufacture and use of the article, as well as a simple removal of the binding threads themselves when, during recycling and after cutting the latter, any kind of hold is to be removed in order to recover the base fibers.

[0190] Conveniently, the manufactured article described in this invention, understood both in its product configuration and in the definition of the production method, may have all the technical features already described in patent application No. 102022000025242 filed by the same Applicant.

[0191] Therefore, all of the article and method features in the above-mentioned application No. 102022000025242 can be included in the following description.

[0192] This invention can be produced in other variants all falling within the scope of the inventive features claimed and described; these technical features can be replaced with different technically equivalent elements and the materials used; the invention can be of any shape or dimension as long as they are compatible with its use.

[0193] The numbers and reference marks included in the claims and description are only intended to increase the clarity of the text and must not be considered as limiting the technical interpretation of the objects or processes identified by them.

Claims

CLAIMS1. Textile article comprising:- at least one fiber substrate;- at least one finishing compound distributed over at least a portion of said fiber substrate; wherein said finishing compound comprises:- a polymeric component suited to define at least one reversible bond with said fiber substrate;- a cross-linking agent suited to define at least one irreversible bond with said fiber substrate and / or with said polymeric component; and wherein said cross-linking agent is chemically compatible with said polymeric component and / or with said fiber substrate to make a structure of a latticetype structure.

2. Textile article according to claim 1 , characterized in that said polymeric component is chosen from polymers of acrylic, vinyl, styrene-acrylic or vinyl-acrylic nature.

3. Textile article according to claim 1 or 2, characterized in that said polymeric component of said finishing compound comprises a dispersion of polymeric particles having an average size between 10 nm and 10 pm.

4. Textile article according to one or more of the preceding claims, characterized in that said cross-linking agent comprises at least one cross-linking monomer provided with at least one functional group suited to establish a cross-linking reaction.

5. Textile article according to one or more of the preceding claims, characterized in that said finishing compound is suited to define a polymer lattice obtained by radical copolymerization in aqueous emulsion of monomers functionalized with cross-linking monomers.

6. Textile article according to one or more of the preceding claims, characterized in that said cross-linking agent comprises at least one additional group of molecules chemically compatible with said at least one cross-linking monomer to establish a crosslinking reaction.

7. Textile article according to one or more of the preceding claims, characterized in that said additional group of molecules of said cross-linking agent comprises a hydrazide of the adipic acid and / or at least one molecule comprising an isocyanategroup.

8. Textile article according to one or more of the preceding claims, characterized in that said finishing compound is chemically compatible with at least one solvent so as to be separated from the fibers of said fiber substrate when a reaction is established with said at least one solvent.

9. Method for producing a textile article, comprising at least the following steps: a) providing at least one fiber substrate of base material; b) association of at least one finishing compound with said fiber substrate; wherein said finishing compound includes:- a polymeric component suited to define at least one reversible bond with said fiber substrate;- a cross-linking agent suited to define at least an irreversible bond with said fiber substrate and / or said polymeric component; and wherein said cross-linking agent is chemically compatible with said polymeric component and / or said fiber substrate to make a lattice structure.

10. Method for producing a textile article according to claim 9, characterized in that it comprises, prior to said association step b), a step of forming said finishing compound, which involves at least the following operational sub-steps: i. providing a first group of monomers; ii. providing a second group of cross-linking monomers; iii. functionalization reaction of said first group of monomers with said second group of cross-linking monomers; iv. copolymerization reaction of said functionalized monomers obtained from said step iii) to obtain polymers comprising said cross-linking monomers; v. cross-linking reaction to obtain a polymer lattice that is susceptible to being bonded to the fibers of said substrate; wherein in said step iii) said at least one monomer of said first group establishes a bond with at least one cross-linking monomer of said second group to obtain functionalized monomers.

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