Method for Enriching a Textile Fiber Bundle Intended for a Spinning Line, Electrospinning Station, Enriched Yarn and Use Thereof

The present invention refers to a method for enriching a textile fiber bundle intended for a weaving machine in a spinning line for transforming fibers into yarn.

The present invention also refers to an electrospinning station, employable in the aforesaid method, as well as a yarn or fabric obtained from a textile fiber bundle enriched according to the aforesaid enrichment method.

In general, in the textile industry non-woven textile materials are known to be produced, such as by thermoforming textile fibers into thermopolymers. Such non-woven textile fabrics (henceforth, NWT) inconveniently have great inherent variability in fiber size.

Within the production methods of NWT, electrospinning provides a solution to the problem of fiber size variability, due to the possibility of greater control over the fiber formation process.

As is known, known electrospinning systems enable the manufacture of NWT materials through the successive deposition of nanofibers onto a substrate, physical typically for the fabrication of membranes or films intended for use in making filters or fabrics for special applications.

Therefore, the traditional electrospinning processes allow for the creation of nanofiber layers, or films, deposited on substrates from which the NWT portions may then be separated. According to some variants, moreover, traditional electrospinning processes allow layers of nanofibers obtained by electrospinning to be deposited on a fabric so as to cover portions of the fabric previously woven from yarns obtained by known spinning techniques.

Such NWT production types turn out to be particularly complex, expensive, and difficult to scale up to a wide scale of fabric types.

Therefore, electrospinning production methods of the prior art are used exclusively for the production of high value-added textiles, such as medical, microbiological and similar applications.

It is thus the object of the present invention to identify a method for producing textile fibers and yarns that integrate the advantages of fiber production techniques by electrospinning to improve the properties of textile fibers and yarns obtained by the prior art.

A further object of the present invention is to identify a method for producing textile fibers and yarns (and thus fabrics) which, in addition to incorporating the advantages of electrospinning production techniques, is also less costly, simpler, and ensures improved volumes and improved production efficiency with respect to the known electrospinning production techniques.

The aforesaid objects are achieved by a textile fiber bundle enrichment method, an electrospinning station, a spinning line, and a yarn or a fabric according to the attached independent claims. The dependent claims describe preferred embodiments.

According to one embodiment of the invention, with reference to, a spinning line, installed in a spinning mill, comprises one or more weaving machines,,,, e.g. comprises one or more blowroom machines(e.g. a plucker, a mixer, an opener, a mixer loader, a scale loader, or a tuft blender), one or more carding machines, one or more combing machines(e.g., a drawing frame, lap winder, or comber), one or more spinning machines(e.g., a roving frame or spinning frame), installed in the spinning mill, and one or more electrospinning stations (,′), arranged upstream or downstream of one or more of the weaving machines.

According to the invention, the electrospinning stationis suitable for enriching a textile fiber bundlewith solid nanofibersgenerated by electrospinning. The textile fiber bundle, once enriched, is preferably intended for processing in a weaving machineof a spinning linecomprising one or more weaving machines, e.g., a blow room machineor a carding machine, or a combing machineor a spinning or slubbing machine.

It is clear that the terms “enrich”, “enriched”, and “enrichment” mean that the basic textile fiber bundle is enriched with additional solid nanofibersfrom the electrospinning process that are not part of the basic textile fiber bundle and generally used in standard processes of the spinning line.

The electrospinning stationcomprises an electrospinning device, preferably a needleless electrospinning device.

The electrospinning devicecomprises a reserve,′ suitable for containing an enrichment solution(i.e., an electrospinnable solution), for example a solution containing natural and/or artificial polymers and/or monomers dissolved in one or more solvents. The enrichment solutionis suitable for forming solid nanofibersby electrospinning that are deposited on the textile fiber bundlein the electrospinning process.

The electrospinning devicecomprises an emitter electrode,′, in some cases known as a spinneret, preferably a rotating electrode (e.g., a rotating drum), suitable for being arranged on a first sideof the textile fiber bundle.

According to one embodiment, the emitter electrode,′ is at least partially or totally bathed in the enrichment solution.

The electrospinning devicecomprises a collector electrode,′ facing and spaced apart from the emitter electrode,′ and suitable for being arranged on a second sideof the textile fiber bundle, opposite to the first side, so that, due to an electric field generated between the emitter electrode,′ and the collector electrode,′, the solid nanofibersare formed starting from the enrichment solutionand these solid nanofibersare transported on the textile fiber bundle, with the consequent deposit of the solid nanofiberson the textile fiber bundlein order to obtain an enriched fiber bundle.

According to one embodiment, for example shown in, the electrospinning stationcomprises one or more bundle winding rollers, wherein each bundle winding rolleris rotatable about its own roller rotation axis Z, Z1,, Z3 for guiding the textile fiber bundleto be wound around the bundle winding rollerin coils(that is, so as to form coils) about the roller rotation axis Z, Z1, Z2, Z3. The one or more bundle winding rollersare arranged between the emitter electrode,′ and the collector electrode,′ so that, due to electrospinning effect, solid fibersare deposited onto a first sideof the textile fiber bundlewound around said one or more bundle winding rollers.

It is clear that the coilsmay be formed partially around the roller rotation axis Z, Z1, Z2, Z3. For example, in the case in which there are multiple winding rollers, the coilsare formed around more than one roller rotation axis so as to span two or more roller rotation axes Z, Z1, Z2, Z3, as for example shown in

According to one embodiment, the electrospinning stationcomprises guide meansconfigured to guide the bundle of textile fibersto form coilsin a helical shape,around multiple bundle winding rollers, so that, in an electrospinning space region S resulting between at least two rollers,;,of said bundle winding rollers, multiple coilsof the same textile fiber bundleare formed, spaced apart along a direction Z′ parallel to the roller rotation axis Z, Z1, Z2, Z3.

This makes it possible to create, in the space region S, a structure of successive coil segments,,of the same fiber bundleside by side and spaced apart, which from time to time are struck with the solid nanofibersfrom the emitter electrode,′ as the textile fiber bundleadvances in the bundle running direction X. Advantageously, the guide means are configured in such a way that the optimal distance between the coilsmay be adjusted according to the type and size of the textile fiber bundle. This makes it possible to minimize the amount of dispersed solid nanofibers, that is, those solid nanofibersthat, when passing between the coils, are not retained on the textile fiber bundleand are deposited on the collector electrode,′. Furthermore, this allows the number of passes of the textile fiber bundlein the region in which the depositing of solid nanofiberstakes place to be optimized according to specific needs.

According to one embodiment, the guide means are suitable for guiding the textile fiber bundlein such a way that the distance between the coilsis increasing or decreasing along the direction Z′ parallel to the roller rotation axis Z, Z1, Z2, Z3. This makes it possible to adjust the appropriate amount of solid nanofibersthat are gradually deposited on the textile fiber bundle, since the amount of solid nanofibersthat are deposited also depends on the amount of solid nanofibersalready deposited.

Preferably, the electrospinning space S resulting between at least two rollers,;,is defined as the region of space facing towards both rollers, that is, the region of space defined between two imaginary planes P1, P2; P3, P4 tangent to an outer surface of the two rollers,;,, parallel to the roller rotation axis Z, Z1, Z2, Z3 of each winding rollerand traversable by the coils.

In particular, advantageously, the guide meansallow the distance between the coilsto be varied without changing the size of the electrospinning space S.

According to one embodiment, the guide meanscomprise protuberances or depressionspresent on each bundle winding roller.

According to one embodiment, the guide means comprise coil guidesthat are either fixed with respect to the one or more bundle winding rollersor movable (e.g., rotatable) independently of the rotation of the one or more bundle winding rollersand are suitable for receiving the textile fiber bundlein sliding contact. Preferably, the fact that the coil guidesare movable independently of the rotation of the one or more bundle winding rollersmeans that they are not directly connected to the bundle winding roller for rotation but may rotate independently or may be dragged in motion by the textile fiber bundleor other transmission system or otherwise may rotate around a rotation axis different from the rotation axis of the bundle winding rollers.

For example, according to one embodiment, the coil guides comprise one or more bulkheads, one or more fixed or rotatable cylinders, one or more posts or a combination thereof, or similar mechanical guides.

According to one embodiment, the coil guides, preferably posts or cylinders (e.g., rotatable posts or cylinders), are placed in the electrospinning region of space S. This allows the spaces of the electrospinning station to be optimized.

According to one embodiment, the coil guides, preferably posts or cylinders (e.g., rotatable posts or cylinders), are placed outside the electrospinning space region S. This allows the electrospinning process not to be affected.

According to one embodiment, for example shown in, the coil guidesare posts or cylinders positioned in such a way as to have their main axis of extension (or of rotation, if rotatable) positioned incident to or perpendicular to the roller rotation axis Z, Z1, Z2, Z3. Moreover, these posts or cylinders are spaced apart along a direction Z′ parallel to this roller rotation axis Z, Z1, Z2, Z3.

According to one embodiment, said posts or cylinders are repositionable along the direction Z′ parallel to the roller rotation axis Z, Z1, Z2, Z3 so that the distance between the posts or cylinders, and consequently the distance between the coils, may be adjusted.

According to one embodiment, for example shown in, each bundle winding rollercomprises protuberances or depressions(that is, the guide meansin the form of protuberances or depressions) for guiding the textile fiber bundleto be wound around the bundle winding rollerin coilsspaced apart along the roller rotation axis Z, Z1, Z2, Z3.

It is clear that, in the variant with the previously described coil guides, for example shown in, each bundle winding rollermay also have a smooth outer surface, without depressions or protuberances.

Preferably, the depositing of the solid fibersoccurs while the textile fiber bundleis moving along a bundle running direction X, preferably a direction incident to or perpendicular to the direction of transport of the enrichment solution from the emitter electrode toward the textile fiber bundle.

According to one embodiment, the one or more bundle winding rollerscomprise a first group of rollers′ and a second group of rollers″, spaced apart from the first group of rollers. The first group of rollers′ is arranged so as to expose the first sideof the textile fiber bundleto the solid fiberscoming from the electrospinning device. The second group of rollers″ is arranged downstream of the first group of rollers′ in the bundle running direction X so as to receive the textile fiber bundlealready enriched on the first sideand so as to expose a second sideof the textile fiber bundleto the solid fiberscoming from the electrospinning device.

Preferably, the second group of rollers″ comprises one or more second group rollers,, each rotatable about its own roller rotation axis Z, Z1 in the opposite direction to the rotation direction of the first group of rollers″, so that the second sideof the textile fiber bundleis easily exposed, and a small footprint of the electrospinning stationis maintained, along with mechanical symmetry and an equal utilization of components.

According to one embodiment, the electrospinning stationcomprises an idler roller′″ arranged between the first group of rollers′ and the second group of rollers″ in the bundle running direction X. The idler roller′″ is out of alignment with respect to the first group of rollers′ and the second group of rollers″. Preferably, the idler roller′″ is rotatable about an idler roller rotation axis Z4 out of alignment with respect to the roller rotation axes Z, Z1, Z2, Z3 of the first group of rollers′ and the second group of rollers″.

Preferably, the roller rotation axes Z, Z1, Z2, Z3 of the first group of rollers′ and of the second group of rollers″ all lie on a single plane of rotation axes. Preferably, the idler roller′″ is out of alignment with respect to the first group of rollers′ and the second group of rollers″ in that its idler roller rotation axis Z4 does not lie on the same plane of rotation axes, e.g., the idler roller rotation axis Z4 lies on a plane parallel to the plane of rotation axes.

According to one embodiment, the first group of rollers′ comprises a first group first rollerand a first group second roller. Preferably, the second group of rollers″ also comprises a second group first rollerand a second group second roller. According to this embodiment, the first group first rollerand the first group second rollerare each rotatable around their rotation axis Z2, Z3 and both in a same first rotation direction R1.

Preferably, the second group first rollerand the second group rollerare also each rotatable around their rotation axis Z, Z1 and both in the same second rotation direction R2 opposite to the first rotation direction R1.

In this way, when the fiber bundleis transported by passing around the first group first rollerand the first group second roller, the first sideof the fiber bundleis enriched; subsequently, when the fiber bundle, already enriched on the first side, is transported by passing around the second group first rollerand the second group second roller, the second sideof fiber bundlethen is enriched.

Thus, it is clear that the present invention also refers to an electrospinning stationthat comprises a textile fiber bundlewhich is transported therein, which is movable along the bundle running direction X and arranged around the first group of rollers′ and the second group of rollers″. When in use, that is, when the electrospinning stationis operational, the textile fiber bundleis therefore preferably arranged around the first group of rollers′ and the second group of rollers″.

According to one embodiment, the textile fiber bundleforms a first helical shapearound the first group of rollers′ and a second helical shapearound the second group of rollers″.

According to one embodiment, the electrospinning stationcomprises a chamberthat contains the electrospinning device.

Preferably, the electrospinning stationalso comprises suction meansconfigured to suction any residual textile fibers inside the chamberand/or fumes deriving from the evaporation of solvents from the enrichment solution.

The present invention also refers to a method for enriching a textile fiber bundlepreferably intended for a weaving machine, such as a blowroom machineor a carding machine, or a drawing machineor combing machine, or a spinning or slubbing machine.

The method according to the present invention comprises the operating steps of:

Preferably, in step b), the first electrospinning stationis positioned in the process of treating or creating the textile fiber bundle, e.g. upstream of a weaving machine, or downstream of a weaving machine, or on a weaving machine(e.g., integrated into the weaving machine), in the bundle running direction X.