Method for providing a nonwoven fabric

Abstract

Method for providing a nonwoven fabric, comprising: a. Providing a mold (100, 200, 300, 400, 500; 600; 700; 800) comprising one or more substrates (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926), wherein at least one first substrate (310, 410, 510; 610; 710; 810) comprises a plurality of openings (611, 612; 711, 712; 811, 812); b. Reversible blocking of at least one of the plurality of openings (611, 612; 711, 712; 811, 812) at least partially; and c. Transferring a plurality of nonwoven fibers (11) onto one or more substrates (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926) comprising at least one reversibly blocked opening.

Description

1. Technical area

[0001] The present invention relates to processes for providing nonwovens, molds used in such processes, and nonwovens obtained by such processes. 2. Description of the state of the art

[0002] Nonwovens are made from randomly arranged fibers or yarns that are bonded together by chemical, mechanical, heat, or solvent-based treatment. Unlike woven or knitted fabrics, the fibers or yarns in nonwovens are typically not arranged in a regular mesh or loop structure.

[0003] Nonwovens are extremely versatile because they can be specifically engineered to exhibit desired properties. For example, they can be engineered to be highly durable and stable, uniform, heat-resistant, and / or environmentally friendly. Therefore, nonwovens are used for a wide variety of products and articles, including clothing and footwear, such as shoes or sports accessories.

[0004] Nonwovens are typically provided in the form of flat layers. Fibers are extruded and laid, preferably uniformly, onto a moving conveyor belt or other flat surface. To ultimately obtain generally three-dimensionally shaped products such as clothing or footwear—or at least parts thereof—from these layers, further processing is required. Further processing steps are also required to provide such layers with details such as specific textures. This means that the layers are cut, welded, embroidered, sewn, and / or joined in post-processing. For example, EP 2 397 594 A2 discloses (heat-) pressing the layers into cast parts with the desired shape and / or details.However, such additional steps inevitably affect the properties of the nonwoven, making it difficult to obtain a fabric with exactly the desired properties, not to mention their impact on overall production times.

[0005] In an alternative approach, known from DE 10 2016 223 571 A1, the fibers are extruded directly onto a three-dimensionally shaped substrate, wherein the substrate has holes through which the fibers are sucked to distribute them uniformly, particularly on concave and / or convex surfaces of the substrate. However, providing such a special, perforated, three-dimensionally shaped substrate is a relatively long and complex process. Furthermore, such substrates are generally limited in size and cannot be easily modified in the event of changing requirements. In particular, such substrates cannot be easily reused for similar, but not identical, articles, which is why the use of this approach is – at least economically – inefficient.

[0006] Another approach is known from US 9 732 454 B2 and US 2013 / 0 285 294 A1. Here, extruded fibers are laid on a conveyor belt having corresponding, complementary structures, for example, in the form of depressions and / or elevations. Similarly, the actual conveyor belt can be wrapped with an additional layer having the corresponding, complementary structures instead of the conveyor belt itself. In both cases, this allows the obtaining of a limited number of predetermined textures; changing the conveyor belt or the wrapped layer to obtain a different texture would usually be too complex and therefore impossible in the industrial-scale production of nonwovens.

[0007] Therefore, there is a need for a process that reduces the number of processing steps necessary to obtain nonwovens with various desired shapes and details. 3. Summary of the invention

[0008] This need is at least partially met by a method according to claim 1.

[0009] A first aspect of the present invention relates to a method for providing a nonwoven fabric comprising reversibly positioning a mold on a conveyor moving through a shower of nonwoven fibers.

[0010] By reversibly positioning a mold on a conveyor, the mold can be changed at will, thereby providing nonwovens with different shapes and details. In fact, each mold can be different, allowing nonwovens of different shapes and sizes to be provided one after the other in any order. The positioning and / or changing of molds can also be performed while the conveyor is in operation. Unlike prior art solutions, a complete stop of the conveyor, for example, to replace the conveyor belt, is not required for the present invention.

[0011] This, in turn, can allow increased customization of nonwovens and the corresponding goods while maintaining speed and production efficiency on an industrial scale: Personalized substrates corresponding, for example, to an individualized last of a tailor-made sports shoe or at least parts thereof, can be easily positioned on a conveyor during normal operation, without requiring stopping or at least slowing down production or even special production processes and / or equipment.

[0012] In fact, the present invention not only allows for maintaining speed and efficiency on an industrial scale, but can even increase it. By positioning molded parts with the desired shape and details on the conveyor, the nonwovens leaving the production line can already be completely finished: Since they are given the desired shape and details during production, there is no need for extensive post-processing.

[0013] Finally, the present invention expands the applicability of conventional production processes. While these are typically used to obtain two-dimensional structures, i.e., layers of nonwoven fabrics as described above, the present invention allows three-dimensional structures to be obtained from these, while no modifications to existing production facilities are required. One can simply continue to use conventional two-dimensional production techniques to obtain three-dimensional, textured fabrics and articles.

[0014] In short, the present invention significantly expands the application possibilities as well as the modularity and flexibility of conventional processes for obtaining nonwovens.

[0015] In one embodiment, a reversibly positioned mold may have at least one depression and / or elevation. These can be used to obtain the desired shape and / or details in the resulting nonwoven fabric. Depressions and / or elevations can have any shape and / or size. A mold may have only one depression and / or elevation. Alternatively, a mold may have multiple depressions and / or elevations. Depressions and / or elevations can be randomly arranged. Alternatively, depressions and / or elevations can be regularly and / or symmetrically arranged. Similarly, depressions and / or elevations can be partially randomly and partially symmetrically arranged. Depressions and / or elevations can be combined, i.e., one elevation can have one or more depressions and vice versa. A depression can also have the shape of a hole, i.e., it can break through the mold.

[0016] In some embodiments, a reversibly positioned mold may be a solid sheet or plate, which may have at least one depression and / or elevation as described above. In other embodiments, a reversibly positioned mold may be obtained by combining two or more substrates so that they at least partially overlap. This may further increase the production modularity and flexibility enabled by the present invention. For example, different substrates may be combined to obtain a desired, possibly three-dimensional, shape. This allows a large number of different molds to be obtained from a relatively small and limited number of different substrates. At the same time, this allows substrates to be reused, thus reducing production and operating costs.For example, the same substrate can be used for a variety of shoe uppers, and different second substrates can be positioned on the first substrate to obtain different details, i.e., textures, in the resulting shoe uppers. In general, more than two substrates can be combined if desired and / or needed. In some embodiments, the substrates can be substantially planar plates and / or templates. These plates and / or templates can have a common outer contour but different details. At least one of the substrates can also have one or more depressions and / or elevations as described above for the mold itself.

[0017] Alternatively, a reversibly positioned mold may be formed from a frame surrounding a grid or mesh. The grid or mesh may be formed from metal or plastic wires. Alternatively, the grid or mesh may be formed from ribbons of plastic, fabric, or paper materials. The wires or ribbons may be uniformly arranged to form holes between the wires or ribbons that have a regular shape. Alternatively, the wires or ribbons may be arranged in a random manner. In contrast to the above embodiment in which the mold is formed from a solid sheet, this embodiment allows for much tighter boundaries between the depressions and / or holes in the resulting nonwoven fabric.

[0018] In another aspect, the present invention relates to a method for providing a nonwoven fabric, comprising providing a mold comprising one or more substrates, wherein at least a first substrate comprises a plurality of apertures, reversibly blocking at least one of the plurality of apertures at least partially; and transferring a plurality of nonwoven fibers to the one or more substrates comprising the at least one reversibly blocked aperture.

[0019] In some embodiments, these substrates may be substantially planar plates and / or templates. These plates and / or templates may have a common outer contour but different details. The openings may have any shape and / or size. They may be arranged randomly or, at least in part, regularly and / or symmetrically. On the one hand, these openings may serve as details ultimately printed on the resulting nonwoven fabric, similar to the one or more depressions and / or elevations described above. On the other hand, air—or any other gas for this purpose—may flow through the openings, thus effectively directing the fibers toward or away from the openings.By blocking at least one of these openings, this effect can be suppressed for these one or more openings, thereby achieving a different shape and / or texture of the resulting nonwoven fabric at least in a region corresponding to the part of the mold comprising the reversibly blocked opening.

[0020] By reversibly at least partially blocking at least one of the plurality of openings, this effect can be controlled and used in a targeted manner. In particular, one can use a single or a few base substrates comprising, e.g., a number of uniformly distributed openings that can be blocked and / or exposed depending on the desired shape and / or details of the nonwoven fabric to be obtained, instead of providing different substrates with different arrangements of openings. This greatly benefits the possibility of customization without sacrificing production speed and efficiency. Furthermore, no complex post-processing is required, since the present aspect allows the provision of nonwoven fabrics with the desired shape and / or details already during production.

[0021] In short, similar to what was described above with respect to the first aspect of the present invention, this second aspect not only allows for further increasing the modularity and flexibility of conventional nonwoven production processes, but can even reduce production costs by allowing substrate reuse. This aspect of the present invention can be combined with the first aspect as described above, with all of the aforementioned details as well as those that follow.

[0022] The method for providing a nonwoven fabric may further comprise applying a pressure differential to at least one of the plurality of openings. This may enhance the above-described effect of the openings. In particular, when a suction force is applied to further draw the fibers through the plurality of openings, the resulting nonwoven fabric may be provided with sharp contours at the edges of each of the plurality of openings. The pressure differential may also be applied to only one of the plurality of openings. Alternatively, the pressure differential may be applied to two or more of the plurality of openings, or to all of them. This may comprise applying a pressure differential to a region comprising at least one reversibly blocked opening. The pressure differential may be uniform across all of the openings to which it is applied. Alternatively, the pressure differential may be varied across the surface of the mold.Varying the pressure difference allows for the creation of a non-uniform shape and / or structure of a resulting nonwoven fabric. The pressure difference can be kept uniform over time while the nonwoven fabric is being produced. Alternatively, the pressure difference can vary over time during the production of a nonwoven fabric. For example, the pressure difference can be greatest at the moment the nonwoven fibers are applied to the mold, and the pressure difference can decrease as the fibers bond, or vice versa. In this way, a density gradient can be achieved across a cross-section of the resulting nonwoven fabric, allowing for further tailoring of its performance and feel.

[0023] The reversible at least partial blocking of at least one of the plurality of openings may comprise introducing a liquid into and / or applying an adhesive tape to at least one opening. These are particularly suitable, yet reversible, ways to at least partially block at least one of the openings. Also, liquids and adhesive tapes can be easily manufactured to follow any shape of a substrate into which they are introduced / applied to. In other embodiments, other means may be used to reversibly block at least one opening, such as one or more plugs. An adhesive tape may be applied over or under the one or more openings to be reversibly blocked.When applied beneath the one or more apertures, the one or more blocked apertures may manifest as an additional, slightly different texture in a resulting nonwoven fabric. In particular, at least partially blocking at least one of the plurality of apertures in this manner does not require any additional, specialized equipment, but rather relies on common, widely available and inexpensive means. This can emphasize the desired effects of the present invention on production modularity and flexibility, while keeping its implementation and operating costs particularly low.

[0024] One advantage of using an adhesive tape to block at least one of the plurality of openings is that it forms a border around a desired shape of a nonwoven fabric, the border having a uniform texture. This can be particularly advantageous when manufacturing fabrics for apparel that require additional finishing steps. For example, when two sides of a glove (front and back) are manufactured using the methods described herein, those two sides can be more easily bonded together around the edges if such edges have a uniform texture, for example, without depressions or bumps.

[0025] Alternatively or additionally, the mold may comprise two or more substrates, wherein a second substrate is arranged at least partially on or below the first substrate to at least partially block at least one of the plurality of openings of the first substrate. This may allow the reversible blocking and unblocking of one or more openings without producing any form of waste, since the substrates can be used multiple times without significant wear, compared to, for example, an adhesive tape. Also, such a second substrate can be easily turned to obtain two mirror-symmetrical pieces of nonwoven fabrics, which may be of significant use in the manufacture of, for example, shoes and gloves.Furthermore, using one or more prefabricated substrates for blocking can accelerate blocking and / or releasing, making the entire production process faster and more efficient. As described above for the application of the adhesive tape, if the second substrate is provided beneath the first substrate, the blocked one or more openings can manifest as additional, slightly different textures in a resulting nonwoven fabric.Furthermore, providing the mold in the form of two or more substrates can allow combining the desired effects of the second aspect with those of the first aspect of the invention: On the one hand, the substrates can comprise specific shapes to obtain the desired overall shape of the resulting composite mold, while at the same time being adjustable relative to each other to control and adapt the textural effect that the (lack of) airflow through one or more reversibly blocked openings can entail. The second substrate can itself comprise a second plurality of openings to further direct an airflow. For example, providing a second plurality of openings that partially block, but also partially overlap, the plurality of openings in the first substrate can result in a slightly angled airflow.Similarly, a suitable arrangement of the second plurality of apertures can create targeted non-laminar and / or turbulent air flows that can have a desired effect on the shape and details and thus on the performance and feel of a resulting nonwoven fabric.

[0026] Alternatively, the second substrate may have no openings. This may allow for a particularly tight sealing of the target opening or multiple target openings. Indeed, the properties of a resulting nonwoven fabric may differ even more significantly in regions corresponding to parts of the mold that include unblocked openings and in regions corresponding to parts of the mold that include blocked openings, which in turn allows for the achievement of particularly sharp contours.

[0027] Like any mold according to the first aspect of the present invention, a mold comprising one or more substrates, at least one of which comprises a plurality of openings, can be positioned on a conveyor moving through a shower of nonwoven fibers. This again allows the advantages described with reference to the first aspect of the present invention to be exploited in the second aspect as well. Indeed, when the mold is placed on a conveyor moving through a shower of nonwoven fibers, the advantages of both aspects can be synergistically combined and integrated. In particular, no expensive and complex adaptations to existing infrastructure are required.

[0028] The molds used in both aspects of the present invention, as discussed above, can be provided, inter alia, by an additive manufacturing step. This can allow for further increasing the flexibility of the corresponding production processes. In particular, the use of additively produced substrates can allow for increased customization. For example, molds can be additively manufactured according to the customer's preferences and / or requirements. In some embodiments, for example, the customer can have his / her foot precisely measured. A corresponding mold in the form of a shoe last, or parts thereof, is then additively manufactured. This mold can then be positioned on a conveyor to provide the customer with a tailor-made shoe in a relatively short period of time, since no special production steps need to be carried out.Rather, the customized mold is incorporated into the already optimized and ongoing industrial-scale production process. In some embodiments, the mold may be provided only partially comprising an additive manufacturing step. For example, while a prefabricated substrate is used for the entire shape of a shoe upper, a second, possibly topmost substrate may be additively manufactured according to the customer's requirements and / or preferences. For example, this allows the texture and thus the feel of a shoe upper to be customized without significantly changing the overall shape. Similarly, by providing a suitable second substrate, the customer's initials, for example, can be printed onto the resulting nonwoven fabric.

[0029] Furthermore, molds can be positioned at least partially using a robotic arm. This can allow the automation and thus potentially further acceleration of the production processes described above. Centralized control over production can also be enabled. In some embodiments, a robotic arm can have access to a number of prefabricated substrates, e.g., plates and / or templates. In response to user input—which in some embodiments can be received from remote locations such as shops on other continents—a robotic arm selects a mold and positions it on the conveyor. Alternatively, the robotic arm can select a number of substrates and combine them on a conveyor such that, as a result, a desired mold is positioned there.This may include positioning a second substrate on or beneath a first substrate to reversibly at least partially block at least one opening therein, as described above. Similarly, the robotic arm may be adapted to introduce a liquid into one or more openings of the first substrate and / or apply an adhesive tape thereto. Subsequently, the resulting mold moves through a shower of nonwoven fibers to produce the desired nonwoven fabric requested by user input. All of this, of course, can be achieved by any type of robot, which need not necessarily have the specific shape of a robotic arm.

[0030] In another aspect, the present invention relates to nonwoven fabrics having an inhomogeneous and / or three-dimensional shape, which are obtained at least partially by one of the methods described above, as well as to clothing or footwear, in particular sports shoes, comprising such fabrics. As is clear from the foregoing, such nonwoven fabrics can be provided on an increasingly individual basis and in an increasingly rapid, inexpensive, and therefore efficient manner. This is made possible in particular by the use of modularly combinable and / or individually manufactured substrates and thus by eliminating the need for extensive post-processing steps as far as possible.

[0031] Among other things, such nonwovens may comprise regions of more or less densely distributed fibers, resulting in different feel and performance characteristics between these different regions. For example, the density of the fibers may influence the air permeability and tensile strength of the corresponding region of the nonwoven. In some embodiments, a region comprising more densely arranged fibers may correspond to a portion of the mold that includes at least one blocked opening.

[0032] In a further aspect, the present invention relates to casting molds that can be used in any of the methods described above.

[0033] In some embodiments, such molds may comprise two or more substrates combined to obtain a depression and / or elevation of the corresponding mold. As described above, the flexibility and efficiency of conventional production processes can be significantly increased by modularly combining two or more substrates to obtain the desired mold shape; a limited number of substrates can allow the molding of a large number of different mold shapes, which benefits the possibility of individualizing the resulting fabrics. In particular, such molds can allow the exploitation of two-dimensional production processes to provide three-dimensionally shaped nonwoven fabrics. At the same time, production costs can be reduced because the molds and substrates used therein can be reused repeatedly without experiencing significant wear.

[0034] Alternatively or additionally, at least one substrate contained in such a mold may comprise a plurality of openings, at least one of which can be reversibly blocked and opened. This allows for the selective modification of, for example, the texture of a resulting nonwoven fabric, thereby further increasing the flexibility and efficiency of production processes known in the art.

[0035] Of course, such molds can be provided by at least partially using additive manufacturing techniques, thereby further simplifying customization. In some examples, the entire mold can be manufactured using an additive manufacturing step. In other embodiments, only one or more substrates used to form the mold can be manufactured in this way, while at least one other substrate is provided without an additive manufacturing step. 4. Brief description of the figures

[0036] Possible embodiments of the present invention are described in the following detailed description with reference to the following figures: Fig. : Exemplary manufacturing facility adapted to carry out the methods according to some aspects of the present invention; Fig. : Exemplary substrates according to some aspects of the present invention; Fig. : Further exemplary substrates according to some aspects of the present invention; Fig. : Exemplary nonwoven fabrics according to some aspects of the present invention. 5. Detailed description of possible embodiments

[0037] For the sake of brevity, only a few embodiments are described below. Those skilled in the art will appreciate that the specific features described with reference to these embodiments can be modified and combined in various ways, and that individual features can also be omitted if they are not essential. The general explanations in the above sections also apply to the following detailed explanations.

[0038] Fig. shows a conveyor 30 moving through a shower 10 of nonwoven fibers 11 (not all labeled). The conveyor 30 moves to the right, as indicated by the arrows 35a and 35b. Shower 10 originates from a fiber transfer device 20, which is arranged above the conveyor 30. In some embodiments, the fiber transfer device 20 can be a meltblown head. In a meltblown process, molten filaments emerge from a spinneret, are drawn through a primary air stream, and broken into rod fibers by eddy currents. A secondary air stream transfers the fibers to the substrate. The meltblown process is a very efficient process for producing nonwoven fibers. However, other processes for producing the nonwoven fibers 11 can also be used, such as a spunbond process. In the embodiment of Fig. The shower 10 has a substantially linear cross-section. In other embodiments, it may have any desired shape. For example, it may have a rectangular, circular, or elliptical cross-section. In some embodiments, the shower 10 can be controlled to vary over time; it can change its shape and / or even stop for certain periods of time. Similarly, the number of fibers, i.e., the density of the shower, can be controlled, all depending on the desired shape and / or details of the resulting nonwoven fabric. For example, the shower 10 can be controlled by user input.

[0039] In the embodiment of the Fig. the conveyor means 30 comprises a conveyor belt 31 which is operated by driving tires 32 (not all labeled). The conveyor belt may have a loop structure so that it has no beginning and / or end. In other embodiments, the conveyor belt may not have a loop structure. Instead, a conveyor layer may be rolled out from some kind of reservoir at a point above the shower 10 and the fiber transfer device 20 and may be rolled back onto and / or into another reservoir at a point below the shower 10 and the fiber transfer device 20. Alternatively, the conveyor layer may be disposed of after use. Furthermore, in a further embodiment, a robot, e.g. a robotic arm, may function as the conveyor means 30.In general, the conveyor 30 can be moved at a constant or variable speed, which can help control the amount of fiber deposited on a given section of the conveyor 30.

[0040] In the embodiment of the Fig. A robotic arm 50 positions molds, such as molds 100, 200, 300, 400, and 500, on the conveyor belt 31. In some embodiments, the robotic arm 50 may have access to a collection of different molds, such as molds 100, 200, 300, 400, 500, and may selectively grasp or otherwise move one or more of them onto the conveyor 30. In Fig. The robotic arm 50 is shown grasping mold 500 for subsequent positioning on the conveyor 30. In other embodiments, the molds 100, 200, 300, 400, 500 are manually positioned on the conveyor 30. In further embodiments, the molds are automatically fed onto the conveyor 30 from a parallel or otherwise arranged auxiliary conveyor, such as a conveyor belt. In general, any form of automation using any type of robot can be used to place molds such as molds 100, 200, 300, 400, 500 onto the conveyor 30.

[0041] Furthermore, Fig. a pressure difference generator 60 arranged below the conveyor 30. In other embodiments, the pressure difference generator may be arranged above the conveyor 30. In yet other embodiments, the pressure difference generator 60 may be arranged at least partially adjacent to the conveyor 30. The pressure difference generator 60 can draw in or discharge air to create an airflow, preferably through the conveyor 30. The pressure difference generator 60 can operate with any gas or gas mix, not just air. The pressure difference generator 60 may have a different shape and size in other embodiments. It may be adapted to provide a uniform pressure difference, both spatially and temporally, but it may also be adapted to create a variable pressure difference.For example, it can create a particularly strong pressure difference below the fiber transfer device 20 to suck nonwoven fibers 11 into the passing conveyor, while creating a smaller pressure difference below the shower 10.

[0042] Casting mold 100 of Fig. is a simple, monolithic, rectangular plate that serves as the first and only substrate 110. In other embodiments, however, a monolithic mold, such as mold 100, or a simple substrate, such as substrate 110, may have a non-planar shape. A mold, such as mold 100, or a simple substrate, such as substrate 110, may indeed have any arbitrary shape, be it substantially two-dimensional or three-dimensional. In particular, such a mold may have at least one recess and / or projection. Recesses and / or projections may have any shape and / or any size. A mold may have only one recess and / or projection, or several. Recesses and / or projections may be arranged randomly or at least partially regularly and / or symmetrically. Recesses and / or projections may be combined, i.e., one projection may have one or more recesses and vice versa.A depression can also be in the form of a hole, i.e., it can penetrate the mold. Depressions and / or elevations can be arranged on any surface of the mold. Although they are preferably arranged on one or more surfaces that are at least partially exposed to the shower 10 of nonwoven fibers 11, they can also be arranged on a remote side. In this case, the elevations can function as spacers, for example, to position the corresponding mold closer to the fiber transfer device 20 and away from the conveyor 30. Alternatively or additionally, separate spacer elements can be used for this purpose.

[0043] In other embodiments, the molds may not be monolithic, but may comprise at least two substrates, such as mold 200, which includes substrates 210 and 220. Substrate 220 has a substantially cuboid shape and is placed on substrate 210, which has a substantially planar shape. However, these shapes are purely illustrative. As explained with reference to mold 100 and substrate 110, respectively, molds such as mold 100 and 200, as well as substrates such as substrates 110, 210, 220, may have any desired shape, be it substantially two-dimensional or three-dimensional. In particular, molds such as mold 100 and 200, as well as substrates such as substrates 110, 210, 220, may have a regular or irregular pattern of depressions and / or elevations, or a mix thereof. This applies to all molds and substrates described herein.A plurality of substrates such as substrates 210 and 220, in particular a number greater than two, can also be combined to obtain a casting mold with a three-dimensional shape, e.g., a casting mold with at least one recess and / or elevation. Substrates such as substrates 210 and 220 can be placed on the conveyor 30 one after the other, or together, in the same way as monolithic casting molds such as casting mold 100. In particular, a robotic arm such as robotic arm 50 can be used for this purpose. However, the other approaches described above can also be applied.

[0044] Mold 300 also includes two substrates 310 and 320. However, in contrast to mold 200, one of the substrates, i.e., substrate 310, includes a plurality of openings. A subset of this plurality of openings is at least partially blocked by substrate 320, which is arranged on substrate 310. Similarly, molds 400 and 500 each include substrates 410 and 510, which include a plurality of openings, but no further substrates on or below the respective substrates 410 and 510. Further details, in particular regarding the arrangement of the openings as well as their reversible blocking, are described below with reference to Fig. described. In any case, a pressure difference generator 60 may be used to generate a pressure difference along and / or an air flow through at least one of the plurality of openings in substrates 310, 410, 510.

[0045] Casting molds 100-500 are moved by a shower 10 of nonwoven fibers 11 through the conveyor 30. In Fig. The mold 400 is currently covered by nonwoven fibers, meaning it has been moved more than halfway through the shower 10. As a result, a nonwoven fabric such as nonwoven fabric 1000 forms on the mold 400—and on all other molds—bearing an imprint of the corresponding mold. In this way, a nonwoven fabric can be obtained that has a desired shape and desired details.

[0046] Fig. show molds 600, 700, 800, each comprising a substantially identical first substrate 610, 710, 810. In the embodiments of Fig. The substrates 610, 710, 810 are essentially planar, ie they can be described as plates. However, just like the substrates 110, 210, 220, 310, 320, 410, 510 of the Fig. take any shape. In particular, they may comprise at least one depression and / or elevation. Substrates 610, 710, 810 each comprise a plurality of openings 611, 612, 711, 712, 811, 812 (not all labeled). In the embodiments of the Fig. the openings 611, 612, 711, 712, 811, 812, etc. are arranged regularly and / or symmetrically. However, in other embodiments, the openings 611, 612, 711, 712, 811, 812, etc. may be arranged randomly, or only partially regularly and / or symmetrically. Fig. Various means are used to at least partially and reversibly block at least one of the openings.

[0047] In Fig. a number of openings of the substrate 610, such as the opening 615, are at least partially reversibly blocked by the introduction of a liquid. In the embodiment of the Fig. The reversibly blocked openings such as opening 615 approximately describe a rectangular or #-like shape. Openings such as opening 615 can be only partially filled with a liquid, so that the remaining free space of these openings can each appear as an additional texture on a nonwoven fabric to be obtained, such as the nonwoven fabric 1000 of the Fig. . The liquid can be introduced manually, for example using a spatula, or automatically, for example by using a robotic arm such as the robotic arm 50 of the Fig. . The liquid can be removed by suction from the openings such as the opening 615, possibly with the aid of a pressure difference generator such as the pressure difference generator 60 of the Fig. Alternatively or additionally, the substrate 610 can simply be lifted from the conveyor 30 so that the liquid drains away. Any type of liquid can be used, in particular water or another widely used liquid. However, in other embodiments, specifically selected liquids can be used. For example, such a specifically selected liquid can facilitate the removal of a nonwoven fabric such as the nonwoven fabric 1000 of Fig. from the mold 600. It should again be noted that the substrate 610 can in principle have any desired shape, in particular a non-planar shape, in other embodiments.

[0048] In Fig. a number of openings of the substrate 710, such as the opening 715, are at least partially reversibly blocked by a layer of adhesive tape, which acts as a second substrate. In the embodiment of the Fig. The layer of adhesive tape 720 is composed of a number of adhesive tape strips such as the adhesive tape strips 721, 722, and 723 (not all marked). The layer of adhesive tape 720 comprises the contour of a T-shirt. Of course, the adhesive tape can be applied in any desired shape, including any contour. In the embodiment of the Fig. the layer of adhesive tape 720 is applied to the substrate 710. In other embodiments, the layer of adhesive tape 720 can be applied to the other side of the planar substrate 710. Then, the one or more reversibly blocked openings such as the opening 715 can manifest as additional, slightly different textures in a resulting nonwoven fabric such as the nonwoven fabric 1000 of Fig. show.

[0049] It should again be noted that in other embodiments, the substrate 710 may have any desired, in particular non-planar, shape and that the layer of adhesive tape 720 may be configured to at least partially follow this shape.

[0050] In Fig. A number of openings of the substrate 810, such as the opening 815, are at least partially blocked by a second substrate 820. Substrate 820 includes a recess 825 that has the same contour as a T-shirt, ie, it can be described as a stencil. It does not include any further recesses and / or openings, although it could generally include such in other embodiments of the present invention. In the embodiment of Fig. only one further substrate, i.e., substrate 820, is placed on the substrate 810. In other embodiments, more than one substrate, such as the substrate 820, can be arranged on the substrate 810 to obtain the desired contour of the depression 825. Furthermore, additional depressions such as the depression 825 can be formed using further substrates. Similarly, elevations can be formed using further substrates, or they can already form part of the substrates 810 or 820. Also, the substrate 820—like any other additional substrate—can be arranged under the substrate 810. Then, the one or more reversibly blocked openings such as the opening 815 can manifest as additional, slightly different textures in a resulting nonwoven fabric, such as the nonwoven fabric 1000 of the Fig. , show. It is also possible to arrange additional substrates, such as substrate 820, on different sides of substrate 810, respectively. In this way, only a subset of the blocked openings, such as opening 815, can show up as textures in a resulting nonwoven fabric.

[0051] Substrates such as substrates 110, 210, 220, 310, 320, 410, 510, 610, 710, 720, 810, 820 can comprise a variety of materials, such as metal, plastic, acrylic, cardboard, or even paper. Particularly in substrates arranged above or below another substrate comprising a plurality of openings, the air permeability of the chosen substrate can be taken into account when selecting the appropriate material. The air permeability can influence the density at which the fibers are arranged on the respective substrate, particularly when a pressure difference is applied to at least one of the plurality of openings of the other substrate. On the other hand, the recyclability and ease of handling of the material can be taken into account. For example, cardboard and / or paper substrates can be widely recycled and easily and quickly obtained. However, they can easily break and wear out.On the other hand, metal substrates can be particularly durable, but relatively difficult and costly to maintain.

[0052] In an exemplary manner, Fig. a number of differently shaped substrates 921, 922, 923, 924, 925, 926 made of cardboard or paper, and adapted to at least partially block at least one of the plurality of openings in a substrate 910 (not shown) similar to substrates 310, 410, 510, 610, 710, and 810. Substrates 921, 922, 923, 924, 925, 926 may also be described as stencils. Substrates 921, 922, 923, 924, 925, 926 may have been cut from a larger piece of cardboard or paper, for example, by hand or by a machine. The machine can be programmed to cut the substrates 921, 922, 923, 924, 925, 926 based on received user input.

[0053] Fig. shows a nonwoven fabric 4000 produced by a method according to the present invention. To produce a nonwoven fabric 4000, a mold 900 (not shown) may have been used. Mold 900 may comprise a first substrate 901 and a second substrate 902. Substrates 901 and 902 may each have a - possibly identical - rectangular outer shape. To produce a nonwoven fabric 4000 of the Fig. To achieve this, substrates 901 and 902 are each formed, for example, at least partially from a mesh. Each mesh may have a rhombic pattern, similar to a wire mesh. The rhombic pattern may vary between the mesh for substrate 901 and the mesh for substrate 902, such that substrate 901 has a different rhombic pattern than substrate 902. In particular, the pattern of substrate 901 may have smaller rhombic shapes than substrate 902.

[0054] Furthermore, the mold 900 may include a third substrate 903. Substrate 903 may be made at least partially of paper. Additionally or alternatively, the substrate 903 may also include one of the other materials described above.

[0055] Substrate 903 may have a first opening having the same shape, e.g. outer contour of the substrate 921 of the Fig. Additionally or alternatively, the substrate 903 may include further openings, each having the shape of a parallelogram. These further openings may be arranged adjacent to the first opening, e.g., between the "legs" of the first opening.

[0056] Mold 900 can be obtained by placing substrates 901 and 902 directly next to each other and then placing substrate 903 on substrates 901 and 902. For example, substrate 903 can be placed centrally on substrates 901 and 902 such that its first opening extends symmetrically across substrates 901 and 902.

[0057] For the production of the nonwoven fabric 4000, the mold can be placed on a conveyor such as the conveyor 30 of the Fig. In addition, a pressure difference generator such as the pressure difference generator 60 of the Fig. have generated an air flow through the mold 90. In particular, an air flow may have been generated such that air flowed from above the mold 900 to below the mold 900. For example, air may flow towards the conveying means such as the conveying means 30 of the Fig. For the production of the nonwoven fabric 4000, the pressure difference, e.g., the suction, may have been uniform.

[0058] Casting mold 900 can then be filled with a shower of nonwoven fibers such as shower 10 of the Fig. have been moved to obtain the nonwoven fabric 4000. As a result, the nonwoven fabric 4000 contains a textured region 4921, the contours of which may correspond to those of the first opening of the substrate 903. The textured region 4921 comprises the part 4921a (on the left side of the Fig. shown) and part 4921b (on the right side of the Fig. Parts 4921a and 4921b are substantially mirror-symmetrical to each other. The dashed line 4921c, which is Fig. shown, reflects the corresponding axis of symmetry. Further textured regions 4927a-4927f may correspond to the further parallelogram-shaped openings of the substrate 903.

[0059] As in Fig. As shown, all textured regions 4921, 4927a-4927f comprise rhombic patterns. These patterns may include depressions. In particular, textured regions 4927a-4927c and part 4921a of textured region 4921 comprise a different rhombic pattern than textured regions 4927d-4927f and part 4921b of textured region 4921. This means that the rhombuses in the pattern of textured regions 4927a-4927c and part 4921a of textured region 4921 are smaller than those in the pattern of textured regions 4927d-4927f and part 4921b of textured region 4921. These different rhombic patterns can correspond to the rhombic patterns of substrates 901 and 902, respectively.For example, the pattern of substrates 901 and 902 may have been imprinted onto textured regions 4921, 4927a-4927f when the nonwoven fibers transferred to mold 900 were at least partially drawn through the openings in the respective mesh of substrates 901 and 902. Accordingly, dashed line 4921c may further be associated with the location of the contact surface between substrates 901 and 902.

[0060] Nonwoven fabric 4000 further comprises a non-textured region 4500 which forms the remaining portion of the portion of nonwoven fabric 4000 which is in the Fig.is visible. The non-textured region 4500 does not include textures like the textured regions 4921, 4927a-4927f because it may correspond to the parts of the mold 900 in which the substrates 901 and 902 were covered by the substrate 903, such that the nonwoven fibers were not at least partially sucked through the openings in the mesh of the respective substrates 901 and 902.

[0061] In the textured regions 4921, 4927a-4927f, the nonwoven fibers may be arranged less densely. Conversely, the nonwoven fibers in the non-textured region 4500 may be arranged more densely.

[0062] Producing a nonwoven fabric 4000 with non-textured region 4500 as described above provides textured regions 4921, 4927a-4927f with sharp contours. Such sharp contours can benefit production accuracy, for example, when the textured regions 4921, 4927a-4927f are to be cut out of the nonwoven fabric 4000 to be applied to another object or for further processing. Alternatively or additionally, at least portions of the non-textured region 4500 of the nonwoven fabric 4000 can remain attached to the textured regions 4921, 4927a-4927f when the latter are cut out. These excess portions can then be used to attach the textured regions 4921, 4927a-4927f to another object or to each other.For example, the textured regions 4921, 4927a-4927f may be sewn to each other over these excess portions, so that the properties of the textured regions 4921, 4927a-4927f as such are not affected by the attachment.

Claims

[1] A method for providing a nonwoven fabric comprising: a. Providing a casting mold (100, 200, 300, 400, 500; 600; 700; 800) comprising one or more substrates (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926), wherein at least a first substrate (310, 410, 510; 610; 710; 810) comprises a plurality of openings (611, 612; 711, 712; 811, 812); b. Reversibly blocking at least one of the plurality of openings (611, 612; 711, 712; 811, 812) at least partially; and c. Transferring a plurality of nonwoven fibers (11) to the one or more substrates (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926) comprising the at least one reversibly blocked opening. [2] The method of claim 1, further comprising applying a pressure differential to at least one of the plurality of orifices (611, 612; 711, 712; 811, 812). [3] The method of any one of claims 1 or 2, wherein reversibly blocking at least one of the plurality of openings (611, 612; 711, 712; 811, 812) comprises at least partially introducing a liquid into and / or applying an adhesive tape to at least one opening. [4] Method according to one of claims 1-3, wherein the mold (100, 200, 300, 400, 500; 600; 700; 800) comprises two or more substrates (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926) and wherein a second substrate (320; 720; 820; 921, 922, 923, 924, 925, 926) is arranged at least partially on or below the first substrate (310, 410, 510; 610; 710; 810). is to at least partially reversibly block at least one of the plurality of openings (611, 612; 711, 712; 811, 812) of the first substrate (310, 410, 510; 610; 710; 810). [5] The method of claim 4, wherein the second substrate (320; 720; 820; 921, 922, 923, 924, 925, 926) does not comprise any openings. [6] Method according to one of claims 1-5, further comprising positioning the mold (100, 200, 300, 400, 500; 600; 700; 800) on a conveyor (30) which moves through a shower (10) of nonwoven fibers (11). [7] Method according to one of claims 1-6, wherein the casting mold (100, 200, 300, 400, 500; 600; 700; 800) is provided comprising an additive manufacturing step. [8] The method of any one of claims 1-7, wherein the mold (100, 200, 300, 400, 500; 600; 700; 800) is positioned at least partially by using a robotic arm (50). [9] Nonwoven fabric (1000; 4000) having an inhomogeneous and / or three-dimensional shape, provided at least partially by a method according to any one of claims 1-8. [10] Nonwoven fabric (1000; 4000) according to claim 9, wherein the fibers of a first region (4500) are arranged more densely than the fibers of a second region (4921, 4927a-f). [11] The nonwoven fabric (1000; 4000) of claim 10, wherein the first region (4500) of the fabric corresponds to a region on the mold (100, 200, 300, 400, 500; 600; 700; 800) comprising the at least one blocked opening. [12] A garment or footwear comprising a nonwoven fabric (1000; 4000) according to any one of claims 9-11. [13] A casting mold (100, 200, 300, 400, 500; 600; 700; 800) for use in methods for providing a nonwoven fabric comprising one or more substrates (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926), wherein at least a first substrate (310, 410, 510; 610; 710; 810) comprises a plurality of openings (611, 612; 711, 712; 811, 812), at least one of which can be reversibly blocked and released. [14] Casting mold (100, 200, 300, 400, 500; 600; 700; 800) according to claim 13, wherein at least one substrate (110, 210, 220, 310, 320, 410, 510; 610; 710, 720; 810, 820; 921, 922, 923, 924, 925, 926) comprising an additive manufacturing step is provided. [15] A casting mold (100, 200, 300, 400, 500; 600; 700; 800) according to any one of claims 13 or 14, suitable for use in a method according to any one of claims 1-8.

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