Patent Application
20240229347
This disclosure relates to the field of dyed textiles and methods for functionalization of dyed textiles, in particular dyed textiles comprising a majority by mass of natural fibers, in particular cotton.
The textile industry has modernized considerably over the last 50 years, in particular by the functionalization of textiles. Functionalization is the treatment of a textile (yarn or fabric or knit) to give it new properties. Among the best-known properties are waterproof treatment (hydrophobic), stain-repellent treatment (hydrophobic and oleophobic), antibacterial treatment or wrinkle-resistant treatment. The treatment may be either chemical (the application of various products), or mechanical (by modification of the surface condition of the fabrics).
The functionalization may be done at the yarn level before it is woven or knit, or after weaving/knitting, on fabric or knit pieces, or assembled articles. The functionalization methods, also called finishing, may be sorted into three groups: preparation and bleaching treatments; coloring treatments (dyeing and printing); finishing treatments (mechanical and chemical finishes, coatings).
When the functionalization step is the final step in the production line for the textile (the dyed textile is bleached, colored and then functionalized), then one speaks of finishing the textile. As for the finishing chemical treatment, the textile may undergo for example one or several baths, with which to impregnate the textile with functionalizing products. Impregnation of the textile may be followed by a crosslinking step with which to create bonds and a network between the functionalizing product and the textile.
Over time and washings, the functionalizing product may tend to separate from the textile, such that the textile loses performance compared to when it came out of treatment. Depending on the kind of functionalization, the textile may lose most of the functionalities thereof after several washings.
This disclosure serves to improve the durability under washing of the functionalization of the textile.
In this context, a manufacturing method for functionalized dyed textile, where the textile is preferably a textile or a knit, is proposed comprising the following steps:
By bleaching before functionalization of an already-dyed textile, the functionalization can better set to the textile, and thus better resist wear and washing, either by machine or by dry-cleaning.
The features disclosed in the following paragraphs may, optionally, be implemented independently of each other or in combination:
According to another aspect, a functionalized dyed textile resulting according to the above method is proposed, optionally having any one or more of the preceding features.
The features disclosed in the following paragraphs may, optionally, be implemented for the resulting functionalized dyed textile, independently of each other or in combination:
According to another aspect, the use of a bleaching solution is proposed for increasing the hold on a dyed textile of a chemical functionalization, where the textile is preferably a fabric or a knit and comprises a majority by mass of natural fibers, preferably cellulose fibers, preferably cotton fibers, and the bleaching solution does not alter the dye of the dyed textile.
Other characteristics, details and advantages will appear upon reading the following detailed description, and analyzing the attached drawings, on which:
Referring to
The method 10 consists of functionalizing an already dyed textile 12, meaning giving it additional properties. The method also aims to increase the durability of the functionalized properties of the textile 12. For that purpose, the method 10 uses a step of cleaning the text out by bleaching before functionalization. This method is innovative in that the cleaning step is not conventionally done after dyeing, except in the case where it is desired that the dyed textile be faded by the bleaching step.
Thus, according to a first step 10-1 of the method 10, the dyed textile 12 is obtained. Textile 12 may be a fabric or a knit. The textile 12 may also be textile yarns before weaving or knitting. If the textile 12 is a woven textile, it may be woven in various ways, like for example simple weaving, canvas, serge, satin, jacquard and variants thereof. The representation from
The textile 12 resulting from the first step 10-1 may come as a roll, in particular if the textile 12 is a fabric. If the textile 12 is a knit, it may come on a roll or a tube. The roll may next be cut in order to form pieces which once assembled will make up an item of clothing. According to an embodiment, textile 12 the resulting from the first step 10-1 may be a shaped piece intended to be sewn to other pieces in order to form a coat. The textile 12 resulting from the first step 10-1 could also be a partially or fully formed item of clothing. According to an embodiment, the textile 12 comes in the form of yarn intended to be woven or knit.
The textile 12 comprises a majority by mass of natural fibers. According to an embodiment, the natural fibers are cellulose, for example cotton or linen. According to an embodiment, the textile 12 is composed entirely of natural fibers, and preferably entirely of cellulose fibers. In that way, the textile 12 may be 100% cotton. According to another embodiment, the textile 12 comprises a minority by mass of fibers obtained from synthetic fibers, preferably fibers selected from elastane filaments, polyamide fibers and polyester fibers; For example, textile 12 contains a minority of polyamide and/or polyester fibers. The textile 12 may contain, one, two or more than two types of fibers, whether they are of natural or synthetic origin. According to an example, the textile 12 is a mixture of yarns made of cotton fibers and yarns made of polyester. According to another example, the textile 12 is made of elastane; the yarns are made up of a core of elastane filaments plated with a skin of cotton fibers.
The textile 12 is already dyed, meaning that a coloring treatment has already been applied to it before obtaining 10-1 the textile. The coloring treatment does not necessarily give a color that is dark or different from white. The coloring may be a bluing step to make it white, as in the case of cotton. The textile 12 may thus be white, light-colored meaning the parameter L from LABCIE1976 is over 60 measured by spectrophotometer, or dark. The textile 12 may be dyed with several colors, in order, for example, to create patterns. The textile 12 may also be dyed a uniform color, like for example, all white or all blue. The textile 12 may also be dyed after weaving (or stitching as the case may be), or else the fibers making up the textile may have been dyed before weaving (or stitching as the case may be) so as to get a dyed textile. It may happen that only some fibers of this textile were dyed. For example, in the case of a textile composed of natural fibers and synthetic fibers, only the natural fibers may have undergone a prior to dyeing.
The coloring applied to the textile is a coloring which will resist the subsequent step of cleaning by bleaching. Meaning that the color will not be altered by bleaching before functionalization. For this reason, indigo is not used. Reactive colorants may for example be chosen, because they are less subject to color loss when they are applied to cellulose fibers. Reactive colorants are characterized by a covalent type attachment to the fiber (covalent chemical reaction between the coloring and the reactive hydroxyl groups of the cellulose). A bleaching before functionalization may also [?] which does not alter the colors. Reactive colorants can also be used in combination with a bleaching which does not alter the colors. By “does not alter the colors” it is understood that the colors do not differ before and after bleaching by a Delta E parameter less than 1.5 and preferably less than 1. The Delta E color deviation is a measurement of the visual difference between two colors in a perceptually uniform colorimetric space L*a*b established in 1976 by the International Commission on Illumination (CIE). For a Delta E color deviation of 1.5, for example, 80% of people are unable to identify a color difference.
According to an embodiment, the dyeing is done after a prior bleaching (or first bleaching). Bleaching consists of the step serving to prepare the textile 12 (woven, knit, or in yarn form) to receive the dye, in particular when it involves natural fibers. Bleaching, which may be done in one or more steps, serves to eliminate natural or artificial impurities from the cloth. Bleaching followed by bluing on a cotton textile, for example, serves to get a white textile. Examples of bleaching are given below.
According to an embodiment, the textile 12 was mercerized. Mercerization is a chemical treatment method applied to cellulose fibers which serves to improve the physical-chemical and geometric properties of the cotton fibers, such as to give them a lustrous appearance. Mercerization may be done on yarn before weaving/stitching or else directly on the fabric/knit. In the following, mercerization on textile will therefore be referred to for designating indiscriminately mercerization on yarn or fabric or knitting.
Mercerization may be done before or after bleaching prior to dyeing of the textile 12, according to whether the fibers have undergone a bluing or not. Thus, according to an embodiment, the textile 12 underwent a step of mercerization comprising an exposure of the textile to sodium hydroxide solution, and the step of mercerization is done before the prior bleaching if the dyed yarns have undergone a first bleaching. And according to another embodiment, the textile 12 underwent a step of mercerization comprising exposure of the textile to a liquid ammonia solution right before bluing, if the textile had a bluing step, otherwise the mercerization step using an ammonia solution is done after dyeing.
After obtaining the dyed textile 12 (meaning procuring or making), the manufacturing method 10 goes on to a second step 10-2 consisting of cleaning of the dyed textile 12 by bleaching in order to obtain a dyed textile 13 free of impurities and where the color has not been altered, before chemical functionalization in the third step 10-3.
The method 10 therefore comprises a bleaching step which was unexpected in that it is done after dyeing and before functionalization. The step of cleaning the textile by bleaching, which is conventionally reserved for the preparation of the textile 12 for dyeing is going to serve in the scope of the method 10 to increase the hold of the chemical functionalization over time. Consequently the functionalization is going to be more resistant to washing (machine or dry cleaning) and to wear. Bleaching of already dyed textile is counterintuitive for the person skilled in the art because conventionally it is never done after dyeing. Bleaching is typically reserved for the preparation of a textile before dyeing thereof, and not after. Since bleaching has properties of cleaning the fiber, the person skilled in the art would not have the idea of applying bleaching to the dyed textile which could alter the color of the textile. However, the inventors found surprisingly, that not only the colors of a textile dyed by reactive coloration were not altered, but the textile 12 better retained the subsequent functionalization. In fact, cleaning by bleaching after dyeing serves to remove impurities from the textile such as adhesives and oils which could still be on the fibers. Because of that, the hold of the hydrophobic functionalization on the textile fibers is increased.
Tests using a spray test (ISO 4920 standard) after washing (ISO 6330) on different cotton tissues dyed by reactive coloration, with and without the bleaching in step 10-2, show that the step of cleaning by bleaching before functionalization serves to increase the stain-repellent properties of the textile. The washing used according to the ISO 6330 standard was done in a type A machine, with type A drying, a type I point overload, a reference 3 detergent, and a 6N washing method. The following results were obtained. These same characteristics will be used in the present document for each result obtained by using the 6330 standard. On average, on 14 cotton textiles tested, with bleaching in step 10-2, the spray test is 4.43 and without bleaching is 3.64. The median with bleaching is 4.5 on spray test and the median without is 3.5. More precisely, with bleaching, two fabrics at 5 on spray test, 10 fabrics at 4.5, one fabric at 4 and one fabric at 3.5 were obtained. Without bleaching, one fabric at 5, three fabrics at 4.5, one fabric at 4, five fabrics at 3.5 and five fabrics at 3 were obtained.
The cleaning by chemical bleaching for the second step 10-2 may be done in the same way as the first bleaching discussed above and whose goal was to prepare the textile 12 for dyeing. The bleaching before functionalization is chemical in that it is subtractive because it “removes” chemical compounds. Bluing, by contrast, is an additive bleaching because it adds a molecule for the purpose of changing the color.
According to an embodiment, the bleaching step 10-2 for the textile 12 comprises an exposure of the textile 12 to a bleaching solution, for example hydrogen peroxide and/or sodium hydroxide (shown schematically in
The bleaching step comprises a drying step in which the textile 12 is rinsed and then dried before going to the functionalization step 10-3. The textile impregnated with hydrogen peroxide and/or sodium hydroxide solution is first rinsed with water before being dried. The drying may be done in open air or else in a drying oven. The drying may be done continuously, on a tenter frame or on a roller in a drying enclosure. The drying can be the passage of the rinsed textile in a oven a 120° C. for 30 seconds in order to remove the water contained in the rinsed textile. At the end of drying, the whitened dyed textile 13 is dry, and there is no sensation of moisture to the touch.
Once the bleached dyed textile 13 is obtained, the method 10 switches to a third step 10-3 consisting of functionalization of the bleached dyed textile 13 in order to get a functionalized textile 14. The functionalization has an increased attachment to the dyed textile because of the prior bleaching in the second step 10-2. The third step 10-3 may be done immediately after the second step 10-2.
Although the method 10 presented here does not comprise intermediate steps between the steps 10-2 and 10-3, according to an embodiment, one or more steps could be done between the steps 10-2 and 10-3. For example, a mercerization step could be inserted between the steps 10-2 and 10-3. The mercerization would then be similar to the one described above.
The functionalization is the treatment of the textile 13 aiming to give it new properties. The functionalization may be mechanical or chemical. The chemical functionalization consists in the impregnation of the textile 13 with the finish (also called functionalizing solution) to give it new properties. The impregnation is followed by a crosslinking of the textile 13 which serves to activate the chains and the polymers of the functionalizing solution. The crosslinking of the textile 13 may be done by going through an oven whose temperature may be included between 140° C. and 200° C., for a time included between 15 seconds and 45 seconds, and which may extend to five minutes. The crosslinking could also be a damp crosslinking, which could take place under damp conditions at 70-90° C. for 8 to 24 hours.
There are various chemical functionalizations which could be applied alone or in addition with each other to the textile 13 to functionalize it. Among the best known are: waterproof treatment, stain-repellent treatment, antibacterial treatment, anti-UV treatment, flame-retardant treatment, wrinkle-resistant treatment, softening, anti-felting, or antistatic. There are also several ways of impregnating the textile 13 with the functionalizing finish, the following can be listed among them: padding, depletion, leaching, spraying, sol-gel treatment, plasma treatment, and coating.
During padding, the textile 13 is plunged in a bath of the functionalizing solution (or finish), and passes between several rollers before coming out of the solution impregnated, which allows the treatment of all of the textile 13 by improving the penetration and the diffusion of the solution.
During depletion, the textile 13 is plunged in one or more baths containing the functionalizing solution without going between rollers. The purpose of this traditional method is to bring the textile into contact with the functionalizing products, and to do so in various types of machine suited for working the material in yarns, parts, and articles such as clothing. These machines operate by circulation of the bath through the textile, the textile in the bath or both at the same time. For example, bath circulation units, commonly called “autoclaves” are used, which can treat large pieces or bobbins of yarn. It is also possible to work with pieces in rope form on overflow type machines. In this case, the chemical products used must have affinity for the textile material in order to be adsorbed, and then to diffuse and attach.
During the coating, the textile is covered (or coated) with one or more polymer layer(s). In general, the textile layer gives the system the properties of strength (again tearing and against pulling) and the properties of stretch whereas the polymer layer serves to give properties, for example, of strength against penetration and permeability (liquids, gases and dust) and also improves the resistance of the textile to abrasion. If the coating involves several layers, they may be bound to each other by the addition of an adhesive to one or both of the layers. The crosslinking serves to shape the polymer to the textile surface (with or without adhesive).
During leaching, the textile is wet by means of a roller (or plates) which is emerged in a vat and which applies a controlled quantity of functionalizing solution on a single side of the textile.
During spraying, fine droplets of functionalized solution are applied on the textile.
During sol-gel treatment, the reactivity of solutions at ambient temperature serves to cover media with low thermal strength such as textile media based on natural and/or synthetic fibers. The method is based on the hydrolysis and condensation of organometallic compounds.
During plasma treatment, the textile surface is placed under a plasma zone. A plasma is an ionized gas composed of electrons, positive or negatively charged ions, neutral atoms and molecules. Cold plasmas, better suited to textiles, are plasmas at ambient temperature, which apply onto the textile in order to give it functionalities.
According to an embodiment, the functionalization 10-3 of the textile 13 aims to give it hydrophobic (or hydrofugic) properties, meaning that the textile 13 does not let aqueous compounds penetrate it. This could be the case for waterproofing the textile. These properties may be along a hydrophobic range going from completely waterproof textile to a textile shedding or simply repelling water. According to an embodiment, the functionalization of the textile 13 aims to also give it oleophobic (or oleophobic) properties, meaning that it does not let fat penetrate it.
If the functionalization of the textile 13 aims to give it hydrophobic and oleophobic properties, the textile 13 may be made substantially stain-repellent. According to an embodiment, the stain-repellent functionalization results from exposure of the textile to at least one bath selected from a solution of perfluorocarbons and/or a solution of silicone compounds in order to give it hydrophobic or even stain-repellent properties. The solution of perfluorocarbons and/or silicone compounds may include only perfluorocarbons and/or silicone compounds, or else contain other compounds in addition to the perfluorocarbons and/or silicone compounds. The exposure of the textile 13 to a perfluorocarbon or silicone compound solution may comprise at least one operation of: padding, depletion, leaching, spraying, sol-gel treatment, plasma treatment, and coating, and crosslinking of the textile 13.
According to another embodiment, the functionalization step 10-3 is a stain-repellent functionalization aiming to give the textile an increased durability of the functionalization. The functionalization step 10-3 then comprises:
In fact, it was observed that the use of the second functionalization step on the textile comprising an exposure of the textile to a silicone composition after a first step of functionalization of the textile comprising an exposure of the textile to a perfluorocarbon solution was able to increase the stain-repellent properties of the textile.
During each of the first or second functionalization steps above, only one of the impregnation operations discussed above may be done (one time or several times), or else a combination of these operations may be done (for example a depletion and a padding in that order or in the opposite order). The first and second functionalization steps may be similar (each being the same operation), or different from each other.
The crosslinking of the textile 13 after the first functionalization step and the crosslinking of the textile 13 after the second functionalization step may each be done by passing through an oven whose temperature is included between 140° C. and 200° C., preferably 170° C., during a time included between 15 seconds and 45 seconds, preferably 30 seconds. The crosslinking of the textile 13 after the first functionalization step and the crosslinking of the textile 13 after the second functionalization step may be done differently from each other, meaning with different drying times and temperatures from each other.
The exposure of the textile 13 to the perfluorocarbon solution during the first step of functionalization serves to give it hydrophobic or even also oleophobic properties. According to an embodiment, the perfluorocarbon solution comprises mostly perfluorocarbons. According to an embodiment, the perfluorocarbon solution comprises perfluorocarbons having six or fewer carbon atoms. Examples of perfluorocarbons used during the first functionalization step are the compounds known in the trade under the name Quecophob MPF-S, Tubiguard 30-F, Quecophob LE 6, or Nuva® 2114 Liq (ARCHROMA 219493). According to an example, an exhaustion bath or a padding solution may be prepared for performing the first functionalization step by having a concentration of 80 g of Nuva® 2114 Liq per liter of water.
The exposure of the textile 13 to the silicone solution serves to give it hydrophobic properties or even also oleophobic properties. According to an embodiment, the solution of silicone compounds from the second functionalization step comprises a majority of silicone compounds. The solution of silicone compounds may comprise compounds selected from polyorganosiloxane, in particular polymethylhydrosiloxane, polyethylhydrosiloxane, polydimethylsiloxane, polydimethylsiloxane, poly(dimethylsiloxane-co-methylhydrosiloxane), poly(methylhydrosiloxane-co-methylphenylsiloxane) or poly(dimethylsiloxane-co-hydro phenylsiloxane) or a mixture thereof, more specifically a polyorganosiloxane crosslinked by a crosslinking agent comprising at least one unsaturated functional group. Exemplary solutions of silicone compounds used during the second functionalization step are the compound known in the trade under the name Bluesil TCS 7001, Bluesil TCS 7110 A&B, Phobotex® WS ConcEco perl HC, Wacker repellent 50 Extender, or Ecoperl active. This silicone compound may for example be used in the case where the textile 13 is made of cotton. Another type of Phobotex® could be used for a textile 13 other than cotton, for example wool. According to an example, an exhaustion bath or a padding solution may be prepared for performing the first functionalization step by having a concentration of 35 g of Phobotex® WS Conc per liter of water.
According to an embodiment, the order of steps between the first functionalization step and the second functionalization step may be reversed. However, it was observed, surprisingly that, when the first functionalization step is done before the second functionalization step, the durability of the functionalization was increased over time. An example of textile functionalization having an increased durability is discussed below. It was observed that the second step of functionalization had an additional effect on the textile in that it protected the functionalization obtained after the first step from wear, and therefore allowed to textile to keep the hydrophobic functionalization thereof, or even stain-repellent, longer than if the second step of functionalization had not taken place.
The stain-repellent functionalization in two steps made it possible to increase the durability of functionalization compared to the application in a single step (meaning mixed perfluorocarbon and silicone compounds), or else if only one of the two functionalizations were done, or even if the order of functionalizations were reversed.
For example, for 16 cotton fabrics tested, some before washing others after washing, some with bleaching others without, on average the results of the spray test 4.53 with the functionalization into steps compared to 4.44 and one step (mixed perfluorocarbon and silicone compounds). In detail, for the functionalization in one step, seven fabrics resulted which had a test spray result of 5, four which had a spray test result of 4.5, two which had a spray test result of 4, two which had a spray test result of 3.5 and one which had a spray test result of 3. In comparison, for the functionalization in two steps, seven fabrics resulted which had a test spray result of 5, six which had a spray test result of 4.5, one which had a spray test result of 4, one which had a spray test result of 3.5 and one which had a spray test result of 3.
The bleach dyed textile 13 may be functionalized so as to give it more than one property. For example, the functionalization of the textile 13 comprises several exposures of the textile to various baths separated by at least one step of crosslinking of the textile, and optionally one or several bleaching steps.
According to an embodiment, the functionalization according to the method 10 is done on a textile 12 already functionalized (for example another type than that from the method 10) obtained in the first step 10-1. In this case, it was observed that not only the bleaching from the second step 10-2 did not change the original functionalization of the textile 12, but further, the subsequent functionalization according to the method 10 made it possible for the original functionalization to last longer.
According to an example, a textile already functionalized wrinkle-resistant in step 10-1 can be functionalized hydrophobic in step 10-3 with method 10. According to an example, the fabric already functionalized wrinkle-resistant underwent an wrinkle-resistant step. The wrinkle-resistant treatment may consist of a resin deposit which does not react with the fiber. In this case, the following resins may be used: phenol-formaldehyde resin, urea-formaldehyde resin, alkyd resin, ketonic resin, vinyl resin, without limitation. According to another example, a crosslinking resin is used in order to create covalent bonds. The crosslinking agents may be nitrogen or non-nitrogen crosslinking agents. These resins of type chemically react with the fiber and crosslink the fiber molecules.
Thus, according to an example, a cotton fabric suited for wrinkle-resistant clothing functionalized hydrophobic with the method 10, may then have a recovery angle after creasing greater than or equal to 130°, measured according to the ISO 2313:1972 standard after having been exposed to up to 40 cycles of machine washing according to the ISO 6330 standard. The recovery angles are between 0 and 180°. An angle near 0, for example 60°, represents a fabric more wrinkled than an angle near 180°, for example 160°. Further, the fabric may then have a spray test result of at least 4 measured according to the ISO 6330 standard.
The recovery angle measured according to the ISO 2313:1972 standard shown here is the average of recovery angles found in the warp and then weft directions of each side of the fabric. The recovery angles measured according to the ISO 2313:1972 standard presented here are between 0 and 180°.
According to an example, a hydrophobic cotton fabric suited for clothing use and previously functionalized wrinkle-resistant may have the following properties from method 10.
By comparison, the same hydrophobic cotton fabric previously having been functionalized wrinkle-resistant has the following properties before undergoing method 10:
Improvement of the stain-repellent and wrinkle-resistant properties are therefore seen because of prior bleaching from step 10-2 and the double functionalization.
According to an embodiment, the method 10 is done by performing the steps 10-1, 10-2 and 10-3 in this order and directly one after the other. Method 10 could include additional steps, before or after some or each step 10-1, 10-2, 10-3.
The present disclosure is not limited to the functionalized dyed textile production method examples and to the functionalized dyed textiles described above, only as examples, but it encompasses all variants which the person skilled in the art could conceive in connection with the protection sought.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2101916 | Feb 2021 | FR | national |
| 2101918 | Feb 2021 | FR | national |
| 2101920 | Feb 2021 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/FR2022/050335 | 2/24/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20240133114 A1 | Apr 2024 | US |
