Apparatus for manufacturing nonwoven fabrics

Abstract

The present invention provides an apparatus for increasing the density of polymer filament extrusion holes, preferably for producing spunbond-type nonwoven fabrics. [Solution] A apparatus 100 for producing nonwoven fabric is provided, comprising a plurality of separate plants configured to produce a nonwoven fabric that unfolds along a main axis 1a and a main plane 1b, and to produce a plurality of polymer, cellulose, or viscose filaments through an outlet along or parallel to a distribution plane 100a that transverses the main axis and the main plane, forming each layer of filaments from the outlet; and a conveying station 12 comprising a calendering means 13 located downstream of the outlet and configured to calender the layers together, and one or more conveyors 15.

Description

Technical Field

[0001] The present invention relates to an apparatus for producing a non-woven fabric of the type specified in the preamble of claim 1.

[0002] Specifically, the present invention relates to an apparatus comprising at least one plant designed to enable the distribution of a polymer fluid exiting the plant in the form of extruded polymer filaments to obtain a non-woven fabric, the plant comprising a spunbond spinneret, or a combination of a spunbond spinneret of either a cusped type or a coaxial multi-lobe type and a meltblown spinneret.

[0003] Furthermore, the present invention also relates to a plant enabling the combination of extruded polymer filaments and cellulose filaments to obtain a non-woven fabric.

[0004] Furthermore, the present invention relates to an article in which continuous polymer filaments, optionally combined with fibrous or particulate cellulose or other synthetic materials, are laminated inside, and to a related process for the formation of articles applicable for filtration or, particularly when the particles are liquid absorbents, for absorbent hygiene articles.

[0005] As is known, non-woven fabric or NWF is an industrial product similar to fabric but obtained by processes other than weaving and knitting. Thus, in non-woven fabric, the fibers have a random pattern and no identifiable ordered structure, while in fabric, the fibers usually have two main and orthogonal directions, called the weft and warp, between the fabrics.

[0006] Currently, a plurality of products containing NWF are manufactured according to the manufacturing techniques used, which are mainly related to the use of the product itself.

[0007] In particular, a distinction is made between high-quality NWF for hygiene products and low-quality NWF used especially for geotextiles.

[0008] From a technical standpoint, nonwoven fabrics can be basically classified into spunlace, spunbond, and multi-row coaxial or cusp melt-blown fabrics.

[0009] Spunlace fabric undergoes a treatment that gives the material isodirectional resistance. Thanks to this property, the possibility of producing it from a variety of materials such as viscose, polyester, cotton, polyamide, and microfiber, two possible finishes, namely smooth or porous, and many smooth or printed colors, spunlace is suitable for both the hygiene sector and the automotive, cosmetic, industrial, or single-use sectors.

[0010] Spunbond, typically made from polypropylene, is a nonwoven fabric with multiple applications in agriculture, sanitation, construction, furniture, mattresses, and other related fields. With appropriate treatment, it is possible to create a range of highly specialized products for various applications, including fluorescent, soft calendering, anti-mite, fire-resistant, antibacterial, antistatic, UV-resistant, and others. Numerous finishes, such as printing, lamination, flexographic lamination, and self-adhesion, are also applicable to spunbond.

[0011] A spunbond nonwoven fabric production plant basically includes at least one polymer material inlet conduit, a polymer extrusion head, a polymer distributor, or a breaker plate, and a spinneret adapted for producing the actual spunbond yarn that is deposited on a conveyor belt.

[0012] The aforementioned elements are arranged appropriately and adjacent to each other so as to enable the processing of the polymer and the distribution of the NWF spunbond.

[0013] More specifically, the polymer inside the dispensing conduit is pushed toward the extrusion head under pressure and at a high temperature, usually exceeding 200°C. In this regard, pressure control is generally performed, for example, using a pressure switch, to ensure the continuity of the output yarn and the accuracy of the deposition process.

[0014] The extruder head distributes the polymer along a distribution surface through which the molten polymer passes as it reaches the distributor. Between the distributor or breaker plate and the extruder head is a filter made of a steel sheet with a thickness typically varying between 0.8 mm and 1.6 mm, containing a fine mesh with nominal dimensions, for example, between 20 μm and 110 μm. Thus, the aforementioned filter is essentially a stretched net.

[0015] After passing through the filter, the molten polymer enters the distributor, from where it proceeds towards the spinneret, which extrudes the polymer into the filaments that make up the spunbond NWF. In detail, the filter is intended to block particles or polymer pigments that are not completely molten or, in some cases, larger, which may clog extremely small extrusion holes in the NWF by entering the spinneret.

[0016] To achieve higher technical characteristics than conventional TNT, NWF meltblown is performed through a specific spinneret. In fact, meltblown fabrics are characterized by fibers that have high filtering power for both liquid and gaseous substances.

[0017] A meltblown nonwoven fabric production plant consists of meltblown fiber manufacturing equipment and a housing containing all the components necessary for the process to function optimally.

[0018] A known cusp melt-blown plant comprises an extrusion head, a cusp distributor, and an air blade.

[0019] A multi-row coaxial meltblown plant provides a system for stretching polymers emerging from horizontally arranged tubes in a coaxial manner, using air that passes from the outside of the tubes and pushes the fibers downward.

[0020] In particular, the multi-row coaxial meltblown plant comprises components that define coaxial holes, which are arranged in a transverse row and adapted to accommodate at least a portion of the aforementioned pipes passing coaxially inside the holes, so as to allow diffusion of the polymer fluid and, at the same time, diffusion of air or gas from at least a portion of the holes.

[0021] Typically, these plants include a device called a spin pack, which contains several different components adapted to interact with each other. A spin pack typically consists of a spinneret and a diffusion device containing one or more components called air plates.

[0022] More specifically, the spinneret of a multi-row coaxial spunbond and / or meltblown spunbond and / or meltblown plant, as currently known, includes a plate having a first bore suitable for housing a tube configured to distribute a polymer fluid, and a second bore separated from the first bore and suitable for allowing the passage of air or gas, and further includes a fixture having a plurality of third bores separated from or integral with the plate and centered relative to the first bore, connected to the second bore via a fluid passage, housing a portion of the tube and simultaneously allowing the passage of the air or gas.

[0023] The prior art described contains several significant drawbacks.

[0024] Specifically, especially in spunbond technology, there is usually a nozzle designed to blow a jet of air downstream of the spinneret, i.e., at the exit point from the filament spinneret, for the purpose of cooling the filament. Cooling the filament before depositing it on the spool tape is important to prevent adjacent filaments from sticking together due to heat.

[0025] However, at the same time, air injection cannot apply excessive pressure to the filaments, because if it does, there is a risk that the filaments will deviate from the exit trajectory and still lead to undesirable mutual adhesion of the filaments.

[0026] In addition to this, since the cooling nozzles are arranged laterally with respect to the exit trajectory of the filaments, the fact that the pressure of the air blown onto the filaments decreases means that the central filaments cannot be cooled efficiently or at least not as well as the lateral filaments, because they are shielded by the lateral filaments. Therefore, from the perspective of the non-woven fabric, technical problems related to performance degradation due to unintended joining of the filaments still remain.

[0027] In addition to the above, it is clear that in order to ensure proper cooling of the filaments, it is necessary to increase the mutual distance between the output filaments, that is, to arrange them at a distance. This means that currently known spinnerets cannot contain high-density holes or distribution pipes, and as a result, a high-density fabric layer cannot be produced.

[0028] Therefore, the layers of non-woven fabric produced by currently known spinnerets are not particularly high-performance when subjected to tensile forces in different directions.

[0029] In fact, the non-woven fabric produced in this way is very robust along the main deployment direction of the plant, but not very perpendicular to that direction.

[0030] The consequences of this drawback have a great impact on, for example, the manufacture of diapers and wet wipes.

[0031] In fact, the above items are usually produced by stacking multiple layers to form the complete layer structure of the item itself.

[0032] Specifically, conventional diapers are typically made according to a lamination sequence (commonly referred to as S, S, MB, MB, S) consisting of two spunbond sheets, two meltblown sheets, and an additional spunbond sheet; tissues have similarities, although tissues also contain intermediate layers that may contain particles.

[0033] In any case, the items I've just described have several major drawbacks when implemented.

[0034] First, these items are manufactured by laminating them onto the same tape, which suggests that multiple different procedures are required, leading to longer lead times. Furthermore, this configuration also suggests that costs will be incurred, not only due to the manufacturing method but also because the cost of the item increases with the number of layers.

[0035] Furthermore, some layers are doubled, particularly in the conventional spunbond spinnerets mentioned above, due to limitations in the density of filament extrusion holes. Therefore, spunbond components need to be fabricated in two layers, and thus in two separate stages and / or devices, typically in multiple booths arranged in series, each equipped with a storage chamber containing the type of spinneret required to produce the desired layer.

[0036] Furthermore, as had already been anticipated, it is known that some items may contain particulate matter. Particulate matter is widely used, for example, within the absorbent structure of absorbent personal hygiene items such as disposable diapers for children, training pants for children, or incontinence underwear for adults, particularly for the purpose of absorbing and containing bodily exudates such as urine, or other moisturizing items such as wet wipes.

[0037] These absorbent articles typically consist of multiple layers that perform different functions, including an absorbent core among a top sheet, a back sheet, and other layers. The absorbent core must be able to absorb and retain liquid exudate for extended periods, such as overnight in the case of diapers, minimizing re-wetting to keep the wearer dry and preventing soiling of clothing or sheets. Modern absorbent cores typically consist of an absorbent structure composed of super-absorbent polymer (SAP) particles, also known as absorbent gelling materials (AGM), and fibrous materials such as natural fibers like cellulose fibers, modified natural fibers like regenerated cellulose-based materials, or synthetic fibers, such as viscose.

[0038] It is well known that absorbent structures can be formed "in-line" or "in-situ" on a conversion line to form a complete absorbent article; for example, referring to WO2022 / 120693A1, this patent discloses an absorbent core for use in an absorbent article, which comprises, in addition to an adhesively fixed cover layer, a liquid-permeable upper cover layer, a lower cover layer, a high-filling-factor core layer between the upper and lower cover layers, and first and second superabsorbent polymers that permeate at least partially into the high-filling-factor core layer. Furthermore, WO2014 / 001487 discloses particles embedded in a porous fabric and ultrasonically immobilized between cover layers.

[0039] However, these methods require each production line of the article, also known as a converter, to be equipped with a suitable processing system for adding particles, as well as a system for unwinding and binding pre-formed tapes. Furthermore, the formation of the absorbent core may limit the overall production volume.

[0040] Instead of forming the core in-line, composite absorbent tapes containing particles such as superabsorbents can be formed offline at high production volumes, which can then be discharged as so-called roll stock into a conversion line for forming articles to be packaged, and / or combined with other elements to form absorbent articles, thereby advantageously simplifying conversion equipment and processes and providing the benefit of lower production costs due to high production volumes.

[0041] Generally, offline molding of absorbent structures offers advantages over in-line molding, such as very high yields from a single production unit; however, there remains a need to improve the economics and / or properties of the resulting absorbent structures. Furthermore, the use of adhesives in absorbent structures can have negative consequences, particularly complicating the recycling of factory waste and leading to consumers perceiving them as unwanted chemicals.

[0042] For example, referring to a typical prior art plant as shown in Figure 13, a further drawback inherent to the adopted technology is that, in the case of multiple plants arranged in a series, the filaments are usually deposited on a stacked loading belt or mat of multiple filament layers.

[0043] This lamination means that during calendering, the layers and filaments are efficiently compressed and compacted, which therefore introduces inherent weaknesses in individual layers and joints, particularly in the formation of multilayer items such as disposable diapers, and degrades the performance of the item.

[0044] In this context, the fundamental technical problem underlying the present invention is to devise an apparatus for producing a nonwoven fabric that can substantially overcome at least some of the aforementioned drawbacks.

[0045] Within the scope of the above technical problems, an important object of the present invention is to obtain a plant for producing a nonwoven fabric, preferably a spunbond type, which increases the density of polymer filament extrusion holes within the same plant.

[0046] Therefore, another important objective of the present invention is to realize a plant for producing nonwoven fabrics in which layers of nonwoven fabric, which are usually produced using multiple separate spindles, can be produced using a single spindle.

[0047] Therefore, a key objective of the present invention is to realize an apparatus for producing nonwoven fabrics that reduce the production costs of layers of hygiene products such as diapers, wet wipes, or other similar items.

[0048] Furthermore, a further objective of the present invention is to realize an apparatus for producing nonwoven fabrics that enables the production of laminated items by reducing process steps and shortening the time required to complete the item.

[0049] In particular, a further objective of the present invention is to realize an apparatus for producing nonwoven fabrics that enable the production of high-performance laminated items in which the layers are highly durable, resistant to wear, and bonded efficiently between different layers.

[0050] Therefore, a further object of the present invention is to obtain an apparatus for producing nonwoven fabrics that can combine different technologies, such as spunbond and meltblown, in order to obtain an item.

[0051] Furthermore, a further objective of the present invention is to obtain an apparatus for producing a nonwoven fabric that allows for the combination of extruded polymer filaments and cellulose filaments in order to obtain a nonwoven fabric.

[0052] Therefore, a further object of the present invention is to create an item having continuous polymer filaments laminated inside, which may be combined with fibrous or particulate cellulose or other synthetic materials, and an associated process for forming an item applicable to filtration, or in particular to absorbent sanitary articles when the particles are liquid absorbents.

[0053] In particular, a further objective of the present invention is to reduce the complexity and cost of manufacturing the items.

[0054] The technical challenges and specific objectives are achieved by an apparatus for producing nonwoven fabrics as claimed in appended claim 1.

[0055] Preferred embodiments are highlighted in the dependent claims.

[0056] The features and advantages of the present invention are clarified below by a detailed description of preferred embodiments of the invention with reference to the accompanying drawings. [Brief explanation of the drawing]

[0057] [Figure 1] This shows a cross-sectional view of a plant for producing nonwoven fabric according to the present invention. [Figure 2] Figure 1 shows an exploded view of the plant. [Figure 3a] This is a perspective cross-sectional view of a rectangular spinneret of a plant for producing nonwoven fabric according to the present invention. [Figure 3b] This is a perspective cross-sectional view of a circular spinneret of a plant for producing nonwoven fabric according to the present invention. [Figure 4] This shows a perspective view of a spinneret holder in a plant for producing nonwoven fabric according to the present invention. [Figure 5a] The diagram shows a schematic upper view of the first hole and slit and the second hole, indicated by hatch lines, of a spinneret for a plant for producing nonwoven fabrics according to the present invention, where the slit is parallel and continuous to the main axis, i.e., a view from the dispenser's perspective. [Figure 5b] A schematic diagram of the top of a spinneret for a plant for producing nonwoven fabrics according to the present invention, showing the first hole and slit and the second hole, indicated by hatch lines, i.e., a view from the dispenser's perspective, is shown, in which the slit is parallel to the main axis and offset between the first and second parts of the spinneret along the main axis. [Figure 5c]The diagram shows a schematic upper view of the first hole and slit and the second hole, indicated by hatch lines, of a spinneret for a plant for producing nonwoven fabrics according to the present invention, where the slit is slightly inclined with respect to the main axis, i.e., a view from the dispenser's perspective. [Figure 5d] A schematic diagram of the lower part of a spinneret of a plant for producing nonwoven fabrics according to the present invention, with the first hole and slit and the second hole indicated by hatch lines, i.e., a view from the perspective of the collection surface, is shown, where the slit is perpendicular to the main axis. [Figure 5e] This diagram shows a schematic view of the lower part of a spinneret for a plant for producing nonwoven fabrics according to the present invention, with the first hole and slit and the second hole indicated by hatched lines, i.e., a view from the perspective of the collection surface, where the slit is strongly inclined with respect to the main axis. [Figure 6] This diagram shows a schematic view of the lower part of a circular spinneret of a plant for producing nonwoven fabric according to the present invention, specifically the first hole and slit and the second hole, indicated by hatch lines, i.e., a view from the perspective of the collection surface. [Figure 7] This diagram shows a cross-sectional view of an apparatus for producing nonwoven fabrics according to the present invention, in which a plant for producing spunbond-type nonwoven fabrics, a plant for producing meltblown nonwoven fabrics, and a plant for producing spunbond-type nonwoven fabrics without an external booth are sequentially arranged parallel to the main plane. [Figure 8a] A schematic diagram of an apparatus for producing nonwoven fabric according to the present invention is shown, in which the conveying station includes a pair of smooth rollers. [Figure 8b] The diagram shows a schematic representation of an apparatus for producing nonwoven fabrics according to the present invention, in which the conveying station includes a first pair of smooth rollers and a second pair of rollers downstream of the first pair, having needles on their contact surfaces. [Figure 8c] The diagram shows a schematic representation of an apparatus for producing nonwoven fabric according to the present invention, in which the conveying station includes a pair of rollers with needles on their contact surfaces positioned near the collection surface. [Figure 9a]The diagram shows a cross-sectional view of an apparatus for producing nonwoven fabrics according to the present invention, in which a plant for producing spunbond-type nonwoven fabrics, a plant for producing meltblown nonwoven fabrics, and a plant for producing spunbond-type nonwoven fabrics are sequentially located within a booth parallel to the main plane, and the conveying station includes two pairs of smooth rollers. [Figure 9b] The booth contains, in sequence, plants for distributing cellulose or viscose, plants for producing spunbond-type nonwoven fabrics, and plants for distributing cellulose or viscose, all arranged parallel to the main plane, and a conveying station including a pair of smooth rollers, as shown in the cross-sectional view of the apparatus for producing nonwoven fabrics according to the present invention. [Figure 9c] The booth contains, in sequence parallel to the main plane, a plant for distributing cellulose or viscose, a plant for producing cusp melt-blown type nonwoven fabrics, and another plant for distributing cellulose or viscose, and a cross-sectional view of the apparatus for producing nonwoven fabrics according to the present invention, in which a conveying station includes a pair of smooth rollers. [Figure 9d] The booth contains, in sequence, plants for distributing cellulose or viscose, plants for producing spunbond-type nonwoven fabrics, and plants for distributing cellulose or viscose, all arranged parallel to the main plane, and a conveying station includes a pair of rollers, one of which is smooth and the other has needles, as shown in the cross-sectional view of the apparatus for producing nonwoven fabrics according to the present invention. [Figure 9e] The booth contains, in sequence parallel to the main plane, a plant for distributing cellulose or viscose, a plant for producing coaxial multi-low melt-blown nonwoven fabric, and another plant for distributing cellulose or viscose, and a cross-sectional view of the apparatus for producing nonwoven fabric according to the present invention, in which the conveying station includes two pairs of smooth rollers. [Figure 9f]Inside the booth, parallel to the main plane, there are sequentially arranged plants for producing multi-row coaxial meltblown nonwoven fabrics, a plant for distributing cellulose or viscose, and another plant for producing multi-row coaxial meltblown nonwoven fabrics. The meltblown plant defines a distribution direction that converges with respect to the distribution plane, and the conveying station includes a pair of smooth rollers. The diagram shows a cross-sectional view of the apparatus for producing nonwoven fabrics according to the present invention. [Figure 10] The diagram shows a schematic cross-sectional view of an apparatus for producing a nonwoven fabric according to the present invention, in which, in the absence of a belt or mat collection surface, the compaction means and calendering means are arranged sequentially parallel to the distribution plane. [Figure 11] The diagram shows a schematic cross-sectional view of an apparatus for producing nonwoven fabric according to the present invention, in which there are multiple separate pieces of equipment at each outlet, each of which is equipped with a conveyor for separately transporting the polymer filament layer to a calendering means in addition to the compaction means. [Figure 12] The diagram shows a schematic cross-sectional view of an apparatus for producing nonwoven fabric according to the present invention, in which there are multiple separate plants at each outlet, each equipped with a conveyor for separately transporting a polymer filament layer to a calendering means in addition to a compaction means, and at least one layer of filament is transported to the calendering means by the plant without a conveyor. [Figure 13] A schematic cross-sectional view of a prior art apparatus for producing nonwoven fabric is shown, clearly indicating the presence of a conveyor belt between the calender outlet and the rollers. [Modes for carrying out the invention]

[0058] In this document, where measurements, values, shapes, and geometric references (such as perpendicular and parallel) are associated with words like "approximately" or other similar terms such as "almost" or "substantially," they should be understood as excluding measurement errors or inaccuracies due to production and / or manufacturing tolerances, and, in particular, as having a deviation of less than a slight from the associated value, measurement, shape, or geometric reference. For example, when associated with a value, such a term preferably indicates a deviation not exceeding 10% of the value itself.

[0059] Furthermore, when used, terms such as “first,” “second,” “upper,” “lower,” “primary,” and “secondary” do not necessarily identify order, priority of relationships, or relative position, but may simply be used to clearly distinguish between their different components.

[0060] Unless otherwise specified, terms such as “processing,” “calculating,” “determining,” “computing,” or similar terms are to be understood as referring to the actions and / or processes of a computer or similar electronic computing device that manipulate and / or transform data, which is expressed as physical quantities such as the amount of electrons in a computer system and / or memory recording, with other data, which is similarly expressed as physical quantities in a computer system, recording, or other information storage, transmission, or display device.

[0061] Unless otherwise stated, the measurements and data reported in this text should be considered to be those provided under the International Standard Atmosphere (ICAO) (ISO 2533:1975).

[0062] Referring to the figure, the plant for producing nonwoven fabric according to the present invention is generally numbered 1.

[0063] The plant 1 for producing nonwoven fabric according to the present invention is preferably of the spunbond type.

[0064] Therefore, like any spunbond plant, plant 1 can at least transport polymer filaments onto a deposition surface for producing nonwoven fabrics.

[0065] As a premise, nonwoven fabrics refer to any type of fabric in which filaments are deposited in a single mass, that is, not classified by a loom or other means that can knit and weave warp and weft threads, but rather, as will be further explained later, are mixed into one or more layers of material by deposition on a deposition surface. Therefore, nonwoven fabrics can be made not only from polyester filaments as conventionally, but also from any natural or synthetic material, such as polypropylene, nylon, cellulose, viscose, and of course, polyester itself.

[0066] Similarly, the term "filament" generally refers to any thread-like element that defines chemical fibers, acrylic fibers, and synthetic fibers.

[0067] Furthermore, it is specified that while Plant 1 is capable of producing nonwoven fabrics, more fundamentally, it is also capable of producing only one or more filaments that can be used for nonwoven fabric formation or for several other purposes, such as unwinding.

[0068] Preferably, plant 1 unfolds mainly along a main axis 1a. The main axis 1a is, for example, a virtual axis of the center of gravity along which plant 1 extends.

[0069] Furthermore, plant 1 also extends along a main plane 1b. The main plane 1b may be provided, for example, preferably by an intermediate plane parallel to the surface on which the polymer filaments constituting the nonwoven fabric are deposited.

[0070] The principal axis 1a may be parallel to the principal plane 1b, and in some cases, may lie on the same plane.

[0071] Furthermore, Plant 1 defines the vertical axis 1c.

[0072] The vertical axis 1c is preferably perpendicular to the principal axis 1a. Therefore, the vertical axis 1c is also preferably perpendicular to the principal plane 1b. Thus, the vertical axis 1c is preferably oriented perpendicular to the surface on which the polymer filaments constituting the nonwoven fabric are deposited and extends along the plant 1 from upstream to downstream.

[0073] Therefore, the vertical axis 1c is essentially an extrusion axis, along which at least a portion of the polymer fluid is transported to a dispenser in plant 1.

[0074] Plant 1, like all spunbond type plants, includes at least one extrusion head 2, one dispenser 3, and one spinneret 4.

[0075] Specifically, plant 1 preferably includes, along the vertical axis 1c, an extrusion head 2, a dispenser 3, and a spinneret 4 in that order.

[0076] Next, the polymer fluid is introduced into the extrusion head 2, then into the dispenser 3, and then distributed to the spinneret 4.

[0077] Preferably, the polymer fluid is selected from polypropylene, polyester, nylon, cellulose, polyester, and viscose.

[0078] The extrusion head 2 is preferably a general-purpose extrusion head, also known by the term coat hanger.

[0079] Preferably, the extrusion head 2 is suitable for guiding the polymer fluid to the dispenser 3. Therefore, preferably, the extrusion head 2 includes at least one main channel 20.

[0080] The main channel 20 is an opening or conduit of any shape or size, and therefore can be cylindrical or rectangular, compatible with other elements to which the main channel 20 is connected.

[0081] The main channel 20 is preferably suitable for the passage of polymer fluid through the extrusion head 2. Specifically, the main channel 20 is suitable for flowing polymer fluid to the dispenser 3. Of course, the extrusion head 2 may also include multiple main channels 20.

[0082] As mentioned above, dispenser 3 receives the polymer fluid from extrusion head 2, specifically from main channel 20, and distributes it.

[0083] Therefore, the dispenser 3 is preferably integrated with the extrusion head 2.

[0084] Dispenser 3 is also referred to as a breaker plate.

[0085] Therefore, the dispenser 3 includes at least one distribution duct 30.

[0086] The distribution duct 30 is connected to the main channel 20 and the fluid passage, and is suitable for distributing polymer fluid. Specifically, the dispenser 30 distributes the polymer fluid to the spinneret 4, and then produces polymer filaments that constitute the nonwoven fabric.

[0087] Both the main channel 20 and the distribution ducts 30 can define complex shapes. Furthermore, they can be divided to provide subchannels for distributing the polymer fluid. In other words, the dispenser 3 may also include a plurality of distribution ducts 30 located downstream of the main channel 20, each designed to distribute a smaller amount of polymer fluid than the main channel 20. Preferably, the dispenser 3 includes a plurality of distribution ducts 30 so that the polymer fluid is distributed along the main plane 1b.

[0088] The dispenser 3 preferably includes at least one housing and filter means.

[0089] This housing is preferably located adjacent to the extrusion head 2 and between the main channel 20 and the distribution duct 30.

[0090] More specifically, the housing can be obtained on the dispenser 3 in the interface region with the extrusion head 2.

[0091] Therefore, the dispenser 3 may include a single housing or may include multiple adjacent housings distributed along the dispenser 3 laterally with respect to the vertical axis 1c.

[0092] The filter medium is preferably housed within a housing.

[0093] Therefore, the housing is essentially a tank in which a filter medium can be placed. The tank is preferably positioned between the main channel 20 and the distribution duct 30, i.e., preferably within the housing, to filter the polymer fluid.

[0094] In particular, preferably, the filtering means includes a porous element.

[0095] Porous elements define multiple non-linear and irregularly sized passage channels.

[0096] Structurally, it is basically similar to a sponge. In this sense, a porous element does not mean a soft element that can be easily deformed. Rather, a porous element is preferably defined in terms of rigidity and hardness by the material and manufacturing process that distinguishes it.

[0097] However, like sponges, porous elements also contain multiple pores that make the porous element itself substantially heterogeneous and anisotropic.

[0098] In particular, porous elements are preferably elements manufactured by sintering technology.

[0099] The porous element preferably includes multiple non-linear passage channels of various sizes, depending on the manufacturing process.

[0100] The term "size" refers to all dimensions that contribute to the volume calculation of cavities or pores that characterize a porous element.

[0101] More specifically, preferably, the filtering means includes a plurality of holes or cavities that, when adjacent, define a passage. In other words, as a result of the holes, a channel for the polymer fluid to pass through is realized.

[0102] Preferably, the porosity of each pore is greater than or equal to 18 μm.

[0103] As mentioned above, the porous element is preferably treated by sintering and therefore contains multiple sintered particles of the same material.

[0104] The particles can then be made of any material, as long as they can withstand the passage of the polymer fluid. For example, porous elements can be made of metallic materials.

[0105] Furthermore, sintered particles can potentially possess a variety of properties.

[0106] For example, in the first embodiment, the particles may be components having the option of being spherical or fragmentary.

[0107] In a second embodiment, the porous element may include filaments that are woven together and sintered.

[0108] In a third embodiment, the porous element may include a first layer and a second layer. These layers preferably overlap each other and each includes components and filaments as described above. More specifically, preferably the first layer and the second layer are adjacent to the extrusion head 2 and the dispenser 3, respectively, and alternately adjacent to the dispenser 3 and the extrusion head 2, respectively.

[0109] Furthermore, single-layer sintering of both particles and filaments can be provided.

[0110] The porous element may be manufactured integrally with the dispenser 3, or, preferably, may be available in a removable manner within the dispenser 3, particularly within the housing.

[0111] Therefore, preferably, the porous element has a complementary shape to the housing and is removably arranged within the housing.

[0112] Therefore, if there are multiple housings, dispenser 3 may include multiple porous elements that can be introduced as tablets within a suitable housing.

[0113] Advantageously, each housing is adapted to accommodate porous elements such that the porous elements are positioned at a distance from the distribution ducts 30. Preferably, especially when the dispenser 3 includes multiple distribution ducts 30, the housing is configured to avoid adhesion between the filtering means and the distribution ducts 30.

[0114] Therefore, generally, the housing is configured to space the filter means and the distribution duct 30 so that at least a separation space is realized.

[0115] The separation space is preferably a portion of the free space between the porous element and the distribution duct 30, and defines a thickness along the vertical axis 1c.

[0116] Preferably, the thickness of the separation space is greater than or equal to 500 μm.

[0117] More preferably, the separation space is between 500 μm and 8 mm.

[0118] Preferably, but not necessarily, the separation space is defined to be thicker than or equal to the thickness of the porous element. In a preferred embodiment, the thickness is defined to be at least 1.5 mm. More specifically, preferably, the porous element is defined to be between 1.5 mm and 8 mm in thickness.

[0119] To achieve separation between the filter medium and the inlet of the distribution duct 30, the housing may include support means.

[0120] The support means is preferably designed to allow the porous element to rest on it, such that the porous element remains within a housing positioned at a distance from the distribution duct 30.

[0121] Therefore, the support means may include a support frame, or at least other spacer elements capable of creating a separation space.

[0122] The spinneret 4 is preferably a separate element from the dispenser 3, as is the case with typical spunbond plants. However, preferably, the spinneret 4 is at least integrated with the dispenser 3.

[0123] Preferably, the spinneret 4 has a plurality of first holes 40. Each of the first holes 40 is preferably spread out laterally with respect to the main plane 1b.

[0124] Furthermore, each of the first holes 40 is preferably connected to a distribution duct 30 and a fluid passage, which is suitable for extruding the polymer fluid to produce each filament, preferably a polymer filament.

[0125] Ideally, the first hole 40 may have a diameter whose dimensions vary depending on the intended use.

[0126] Furthermore, the first hole 40 can be formed into a circular shape or define other shapes laterally with respect to its unfolding axis, i.e., defined by the cross-section of the first hole 40 of different shapes and sizes. For example, the first hole 40 can define a circular, square, or triangular contour with acute or preferably chamfered corners, and may also exhibit concave or convex portions.

[0127] Advantageously, the spinneret 4 of the plant 1 according to the present invention includes at least one slit 41.

[0128] The slits 41 are preferably aligned parallel to the main plane 1b. Therefore, the slits 41 are suitable for air to pass through the spinneret 4.

[0129] The slit 41 may extend to the left and right of the spinneret 4. Alternatively, the slit 41 may also extend only partially within the spinneret 4.

[0130] Therefore, the spinneret 4 also advantageously includes a second group of holes 42.

[0131] The second hole 42 is connected to the slit 41 as a fluid passage.

[0132] Next, a second hole 42 is opened parallel to the first hole 40 so that air can escape from the slit 41.

[0133] Therefore, the first hole 40 and the second hole 42 are deployed along or parallel to one or more distribution directions 4a that are in line with the direction of the air from which the polymer filament is extruded and which pushes the filament out of the plant 1.

[0134] Therefore, one or more distribution directions 4a correspond to directions along the direction in which polymer filaments are distributed from the spinneret 4.

[0135] The second holes 42 are preferably distributed throughout the spinneret 4, so that the air exiting the spinneret 4, particularly from the slit 41, can interact with the polymer fluid exiting from all the first holes 40.

[0136] Furthermore, the slit 41 is unique and can be extended parallel to the main plane 1b to connect with all the second holes 42 and fluid passages.

[0137] Alternatively, the spinneret 4 may have a plurality of slits 41 connected to fluid passages, each slit 41 of which may be connected to a group of second holes 42.

[0138] In fact, preferably, the first holes 40 are arranged in a first row 40a.

[0139] The first row 40a is essentially a row of distinct, separate, and parallel first holes 40. Therefore, the slits 41 are preferably distinct and separated from each other. Furthermore, the slits 41 are arranged parallel to the first row 40a and between adjacent first rows 40a.

[0140] More specifically, the slit 41 is deployed so as not to interfere with the first hole 40. Furthermore, advantageously, the spinneret 4 includes a group of multiple second holes 42, each of which is connected to a fluid passage, along with each slit 41.

[0141] Furthermore, the spinneret 4 can be defined to have a specific shape and size that matches the structure of the plant 1, for example, the dispenser.

[0142] Therefore, for example, the spinneret 4 can be defined as a rectangle, or more generally, a square, or even a round shape such as a circle.

[0143] Therefore, the spinneret 4 can determine a specific orientation for the first row 40a relative to the main spindle 1a, and thus for the slit 41 as well.

[0144] For example, in the first embodiment shown in Figures 5a to 5b and Figure 6, the first column 40a can be unfolded parallel to the main axis 1a.

[0145] Alternatively, as shown in Figures 5c to 5e, the first column 40a may be extended laterally with respect to the main axis 1a, resulting in it being perpendicular to the main axis 1a (Figure 5d) or oblique to the main axis 1a (Figures 5c and 5e).

[0146] In any embodiment, the spinneret 4 can be divided into a plurality of parts or regions. For example, the spinneret 4 may include a first part 4' and a second part 4'.

[0147] If a first portion 4' and a second portion 4'' exist, for example as shown in Figure 5b, the first portion 4' and the second portion 4'' each contain a first row 40a that is offset from each other, with each first row 40a of the first portion 4' aligned in a line with each slit 41 of the second portion 4'', and conversely, each first row 40a of the second portion 4'' aligned in a line with each slit 41 of the first portion 4'.

[0148] The second hole 42 can also be positioned in a specific manner.

[0149] For example, advantageously, one or more second holes 42 from the group of second holes 42, preferably the second holes 42 from each group, are arranged in at least one pair of second rows 42a.

[0150] The second columns 42a are distinct from each other, separated, and parallel. Therefore, each of the second columns 42a is preferably located near each of the two adjacent first columns 40a.

[0151] Furthermore, advantageously, the second holes 42 of each second row 42a are preferably offset from the first holes 40 of the adjacent first row 40a, and as a result are positioned laterally between two adjacent first holes 40 of the first row 40a.

[0152] In this way, the second hole 42 allows the air that has come out of the spinneret 4 to be extruded so as to surround all the filaments that have come out of the first hole 40.

[0153] Since the slit 41 is suitable for allowing air to pass through, preferably the plant 1 also includes a conveying means 5.

[0154] The conveying means 5 is connected to the slit 41 and the fluid passage. Therefore, the conveying means 5 is configured to convey air into the slit 41.

[0155] Therefore, the air being transported is displacement air, and thus, before the polymer fluid leaks out of the spinneret 4, it is possible to cool the polymer fluid at least from the outside through the first hole 40.

[0156] Furthermore, since air also escapes from the second hole 42 adjacent to the first hole 40, the polymer fluid is further directly cooled both immediately near the outlet of the spinneret 4 and between the first hole 40, as described above.

[0157] This technical configuration is highly advantageous, as will be explained in more detail later.

[0158] In addition to what has been described, Plant 1 may include further details.

[0159] As mentioned above, the spinneret 4 is preferably separated from the dispenser 3 and can be defined, for example, as a rectangle (Figure 3a) or a circle (Figure 3b). Therefore, plant 1 may further include support 6.

[0160] For example, the support 6 shown in Figures 1-2 and 4 is integrated with the dispenser 3 if present. Therefore, the support 6 is suitable for supporting the spinneret 4 so that it remains integrated with the dispenser 3.

[0161] In this respect, preferably, the support 6 includes a housing 60.

[0162] The housing 60 is perforated to accommodate the spinneret 4 without blocking the holes 40, 42. Therefore, preferably, the conveying means 5 includes one or more conveying ducts 50.

[0163] One or more transport ducts 50 are preferably deployed between the extrusion head 2, the dispenser 3, and the support 6. Furthermore, the transport ducts 50 are connected to fluid passages with one or more slits 41, preferably one transport duct is connected to fluid passages with all of the slits 41, or each of the transport ducts is connected to the same slit 41 or to each other's slits 41.

[0164] In conclusion, the plant 1 preferably includes an extrusion head 2, a dispenser 3, and a support 6, which are different from each other, separate, and constrained to each other in this order. Thus, the spinneret 4 is removably constrained to the support 6, which is enclosed within a housing 60 between the dispenser 3 and the support 6.

[0165] Therefore, plant 1 is preferably capable of extruding polymer filaments along and parallel to the distribution direction 4a, where the distribution direction 4a may be parallel to or even inclined with respect to the vertical axis 1c.

[0166] Preferably, plant 1 is used to produce a nonwoven fabric. Then, preferably, the filaments are deposited on a movable deposition surface such that at least one woven filament layer is formed during deposition.

[0167] However, Plant 1 can also be used for the fabrication of filament reels. In this regard, for example, one can plan to arrange one or more reels, which are unfolded parallel to the main spindle 1a and rotate around an axis parallel to it, so as to be tangent to the distribution direction 4a, so that the filaments are collected on the rotating reels.

[0168] In this way, by employing a loom that can rewind the filament and weave it into the warp and / or weft threads, the filament can also be used in actual weaving.

[0169] Similarly, the present invention does not include only the new plant 1.

[0170] In fact, this invention makes it possible to manufacture new devices.

[0171] Specifically, the present invention makes it possible to use at least one new apparatus for producing nonwoven fabrics, which is collectively referred to as 100 when referring to the figure.

[0172] It is important to explain from the outset whether or not the apparatus 100 may include plant 1.

[0173] Furthermore, the device 100 can be configured according to different modes, and more specifically, according to several different advantageous configurations.

[0174] For example, in various embodiments, the apparatus 100 may include a booth 10, as is the case with most apparatuses involving spunbond or meltblown plants.

[0175] If a booth 10 exists, it typically comprises a housing that contains a plant capable of dispensing filaments, such as plant 1. In an example where plant 1 is located in booth 10, booth 10 includes all the components of plant 1, such as the extruder head 2, dispenser 3, spinneret 4, and possibly additionally, a support 6 and transport means 5. Alternatively, in this example, booth 10 may also include only the spinneret 4, and possibly the support 6, to house the filaments in a sealed environment.

[0176] Therefore, booth 10 defines a sealed containment container, that is, a container that cannot be accessed from the outside.

[0177] Furthermore, Plant 1 includes an outlet 10a.

[0178] Generally, plant 1 is configured to actually extrude multiple filaments of a type selected from polymer, cellulose, or viscose through outlet 10a.

[0179] Preferably, discharge is achieved by the Venturi effect.

[0180] Therefore, distribution is preferably carried out parallel to one or more distribution directions 4a that traverse the main plane 1b.

[0181] If booth 10 exists, booth 10 may include exit 10a.

[0182] Next, the outlet 10a can correspond to the part of booth 10 from which the filament distributed by the plant located within booth 10 can be discharged.

[0183] Typically, spunbond or meltblown plants, as well as other plants suitable for distributing filaments, are three-dimensional objects that unfold along a plane that intersects the distribution direction 4a, similar to the main plane 1b of plant 1. Therefore, the outlet 10a is essentially unfolded along the distribution plane 100a. The distribution plane 100a is preferably a virtual plane that intersects the main axis 1a and the main plane 1a, along which or parallel to it the filaments are distributed.

[0184] Therefore, the filament discharged from the outlet 10a preferably forms a filament layer along the distribution plane 100a or parallel to the distribution plane 100a.

[0185] Therefore, the outlet 10a can structurally define a distribution slit whose region extends laterally with respect to the distribution plane 100a.

[0186] In fact, the outlet 10a preferentially defines a volumetric constriction configured to allow multiple filaments to be distributed from the plant 1, for example, the booth 10. Such constriction allows the filaments to be distributed, particularly by the Venturi effect, by forming a set of filaments at the outlet, and as a result, a filament layer is formed along or parallel to the distribution plane 100a, as described above.

[0187] Regardless of the presence or absence of booth 10, plant 1 preferably also includes funnel portion 10b.

[0188] The funnel portion 10b is preferably positioned upstream of the outlet 10a. The funnel portion 10b then converges, guiding the filament to the outlet 10a.

[0189] This means, for example, if plant 1 includes a booth 10, the filament will accumulate on the wall of the funnel portion 10b of booth 10 and slide down on its own to the exit 10a.

[0190] In the embodiment, the apparatus 100 may further include one or more collection surfaces 11.

[0191] The collection surface 11 may substantially correspond to a surface previously referred to as a deposition or deposition surface. Thus, the collection surface 11 extends laterally with respect to the distribution plane 100a downstream of the outlet 10a. Therefore, the collection surface 11 is configured to collect the output layer from the outlet 10a to produce a nonwoven article.

[0192] As mentioned above, the apparatus 100 may include a spunbond type plant 1 as described.

[0193] More generally, apparatus 100 may include a plant for producing any nonwoven fabric. The plant for producing any nonwoven fabric may, but is not necessarily, be housed in booth 10 within apparatus 100.

[0194] Therefore, the plant unfolds along the main axis 1a and main plane 1b that traverse the distribution plane 100a. Furthermore, the plant is configured to distribute at least one filament of a selected type from polymer, cellulose, or viscose toward the outlet 10a along one or more distribution directions 4a that traverse the main plane 1b.

[0195] In the first embodiment of the apparatus 100, the apparatus 100 may or may not include the booth 10.

[0196] In fact, preferably, the apparatus 100 generally includes at least one plant as described above, and one conveying station 12.

[0197] Therefore, in summary, the plant is configured to distribute multiple filaments of any type of polymer or cellulose or viscose through outlet 10a, along and parallel to one or more distribution directions 4a that cross the main plane 1b, forming a layer of filaments along or parallel to the distribution plane 100a at outlet 10a, and preferably, especially if a booth 10 is also present, not necessarily by the Venturi effect.

[0198] On the other hand, the transport station 12 is preferably located downstream of the outlet 10a.

[0199] The conveying station 12 is basically suitable for conveying the filament layer to the outside of the plant. Therefore, for example, the apparatus 100 may include a winding machine 16.

[0200] If a winding machine 16 is present, it can be configured to wind the layers onto itself to form a reel. Therefore, the conveying station 12 can be configured to convey the output layers from the outlet 10a to the winding machine 16.

[0201] Of course, the path between the transport station 12 and the winding machine 16 can be facilitated by the presence of additional elements. In fact, the apparatus 100 may also include a transfer device 17.

[0202] If a transfer device is present, the transfer device 17 is configured to transfer the layers from the conveying station 12 to the winding machine 16. For example, the device may include, for example, one or more secondary rolling elements suitable for holding the sliding belt using a vacuum system.

[0203] Advantageously, the transport station 12 generally includes at least a calendar means 13.

[0204] The calendering means 13 is a means that enables the layer to be calendered, which is a well-known industrial process of compressing and stretching a layer by sliding it in a gap such as between two wheels to reduce the local thickness of the layer.

[0205] Therefore, the calendar means 13 is advantageously positioned at a distance of 0 to 5 meters from the outlet 10a. The collection distance can be, for example, between 0.1m and 3m, more specifically, preferably between 0.5m and 1.5m, and more appropriately, a shorter distance such as 1m.

[0206] The conveying station 12 in this embodiment is advantageous in that it does not have a collection surface such as a belt or mat collection surface 11 located upstream of the calendering means 13. This means that the apparatus 100 can convey the layers out of the plant so that the layers are calendered directly by the calendering means 13 without being pre-accumulated on a belt or mat collection surface, as clearly shown in Figure 10.

[0207] By avoiding filament deposition, the strength of the nonwoven fabric layer can be increased. Furthermore, it becomes possible to manufacture nonwoven fabric articles without laminating various uncompressible layers on the deposition surface, but in some cases by appropriately combining them only after calendering.

[0208] Of course, additional components can be included to further improve the plant.

[0209] For example, the transport station 12 may also include a compaction means 14.

[0210] If a compaction means 14 is present, it is positioned between the outlet 10a and the calendering means 13. The compaction means 14 is then configured to compress the layer in order to weave together the strands of the layer before the layer is conveyed to the calendering means 13.

[0211] Therefore, preferably, the compaction means 14 applies greater pressure to the filament layer compared to the calendering means 13.

[0212] Therefore, the calendering means 13 and / or compaction means 14 may include additional details.

[0213] For example, the calendar means 13 may include a pair of first rollers 13a.

[0214] If a first roller 13a is present, it preferably rotates in the opposite direction. Furthermore, the first rollers 13a are aligned parallel to the main plane 1b. Thus, they are configured to rotate around their respective axes of rotation, which are oriented relative to the main shaft 1a, and to convey the layers out of the outlet 10a under pressure.

[0215] Of course, the first roller 13a can be fixed to the main shaft 1a or selectively rotated.

[0216] The first roller 13a more specifically includes a first contact surface 130.

[0217] The first contact surface 130 is part of the first roller 13a, which is suitable for contacting the filament discharged from the outlet 10a.

[0218] Therefore, the first contact surface 130 can be smooth.

[0219] Alternatively, the first contact surface 130 may include one or more knurling. If knurling is present, when the filament comes into contact with the first contact surface 130, the knurling is configured to pick up the filament from the outlet 10a along the distribution plane 100a. Furthermore, if knurling is present, the knurling is also configured to regularly release the filament when the layer is released from the first contact surface 130.

[0220] In a particularly advantageous embodiment of the device 100, the first contact surface 130 preferably includes a plurality of first needles 131.

[0221] The first needles 131, if present, are distributed radially around the axis of rotation along the axis of rotation. Furthermore, the first needles 131 protrude from the first contact surface 130.

[0222] Therefore, based on this structure, the first needle 131 is configured to punch the nonwoven fabric layer extruded from the outlet 10a to form punches distributed on that layer. Advantageously, during punching, the filaments are woven together and sealed.

[0223] Similarly, the compaction means may include a pair of second rollers 14a.

[0224] If a second roller 14a is present, it preferably rotates in the opposite direction. Furthermore, the second roller 14a is aligned parallel to the main plane 1b. Thus, they are configured to rotate around their respective axes of rotation, which are oriented relative to the main shaft 1a, and to convey the layers out of the outlet 10a under pressure.

[0225] Of course, the second roller 14a can be fixed to the main shaft 1a or selectively rotated.

[0226] The second roller 14a more specifically includes a second contact surface 140.

[0227] The second contact surface 140 is part of the second roller 14a, which is suitable for contacting the filament discharged from the outlet 10a.

[0228] Therefore, the second contact surface 140 can be smooth.

[0229] Alternatively, the second contact surface 140 may include one or more knurling. If knurling is present, it is configured to pick up the filament from the outlet 10a along the distribution plane 100a when the filament comes into contact with the second contact surface 140. Furthermore, if knurling is present, it is also configured to regularly release the filament when the layer is released from the second contact surface 140.

[0230] In a particularly advantageous embodiment of the device 100, the second contact surface 140 preferably includes a plurality of second needles 141.

[0231] The second needles 141, if present, are distributed radially around the axis of rotation along the axis of rotation. Furthermore, the second needles 141 protrude from the second contact surface 140.

[0232] Therefore, based on this structure, the second needle 141 is configured to punch the nonwoven fabric layer extruded from the exit 10a to form punches distributed on the layer. Advantageously, during punching, the filaments are woven together and sealed.

[0233] The calendering means 13 and the compacting means 14 can also be arranged according to a specific structure; in practice, preferably, the calendering means 13 and the compacting means 14 are arranged sequentially along the distribution plane 100a so as to transport the layers along the distribution plane 100a.

[0234] The configuration of the apparatus 100 according to the present invention, as described above, enables a new process for manufacturing nonwoven fabric articles.

[0235] This process is, of course, carried out by the device 100.

[0236] Therefore, this process advantageously includes at least one transport stage.

[0237] During the conveying stage, preferably, the layers are conveyed from the outlet 10a to the calendering means 13 without being pre-deposited on the belt or mat collection surface.

[0238] More specifically, advantageously, during the transport phase, the layers may also be compacted and, in some cases, punched to form punch holes distributed on the layers, which are then interwoven and sealed together.

[0239] Therefore, this process, advantageously, also includes a calendar stage.

[0240] During the calendaring stage, the layers are calendared by the calendaring means 13.

[0241] Of course, the present invention also includes nonwoven articles produced by the process described above.

[0242] The embodiment of the device 100 described above can also be modified.

[0243] In fact, in the second embodiment, the apparatus 100 preferably includes a plurality of separate plants and conveying stations 12.

[0244] In summary, as previously described, each plant is deployed along a main axis 1a and main plane 1b that traverse the distribution plane 100a. Furthermore, the plant is configured to distribute at least one filament of a selected type from polymer, cellulose, or viscose toward the outlet 10a along one or more distribution directions 4a that traverse the main plane 1b. Furthermore, the plant may or may not be equipped with a booth 10. Since the multiple plants are preferably separate, they are preferably not located within the same booth 10.

[0245] Therefore, the conveying station 12 preferably includes a calendering means 13. The calendering means 13 may or may not include the detailed components described above, namely the first roller 13a, the first contact surface 130, and the first needle 131.

[0246] Advantageously, in this second embodiment, the transport station 12 also includes one or more conveyors 15.

[0247] One or more conveyors 15 are each positioned between their respective outlets 10a and the calendaring means 13. Therefore, for example, the apparatus 100 may include a conveyor 15 positioned between the outlet 10a and the calendaring means 13 of one plant, as shown in Figure 12, but not between the outlet 10a and the calendaring means 13 of the other plant. Alternatively, as shown in Figure 11, the apparatus 100 may include a conveyor 15 for each outlet 10a of each plant upstream of the calendaring means 13.

[0248] Advantageously, one or more conveyors 15 are configured to transport each layer separately from the other layers to the calendaring means 13. In particular, the layers are configured to be stacked only in the calendaring means 13.

[0249] Therefore, in this second embodiment, the same calendering means 13 is used to calender multiple different layers of filaments distributed from different plants, starting from each outlet 10a, thereby avoiding the layering of different layers on the same surface before calendering 13.

[0250] To further improve the performance of the articles discharged from the calendering means 13 and, if applicable, transported to the winding machine 16 via the transfer device 17, the apparatus 100 may also include a compaction means 14.

[0251] If a compaction means 14 is present, it is located downstream of one or more outlets 10a. Therefore, if a compaction means 14 is present, it is located between the outlets 10a and the calendering means 13. The layers are then configured to be compressed to weave the filaments together and seal them before being transported to the calendering means 13.

[0252] More specifically, advantageously, one or more conveyors 15 are positioned between the compaction means 14 and the calendering means 13 so as to be able to transport already compacted layers.

[0253] The compaction means 14 may also include the aforementioned details, namely the second roller 14a, the second contact surface 140, and the second needle 141.

[0254] On the other hand, from a structural standpoint, one or more conveyors 15 may each be equipped with a collection surface 11. As described above, the collection surface 11 extends laterally with respect to the distribution plane 100a downstream of the outlet 10a and collects the layers discharged from the outlet 10a. The collection surface 11 is then configured to transport the layers to the calendering means 13. For example, the collection surface 11 can be made up of a moving belt or mat. Alternatively, one or more conveyors 15 may be made up of chutes, rollers or other elements capable of determining a path through which layers can reach the calendering means 13 independently of other layers.

[0255] Furthermore, one or more conveyors 15 can be independently positioned relative to the calendaring means 13.

[0256] In fact, the calendaring means 13 is preferably positioned at a distance from at least one of the one or more conveyors 15. Furthermore, at least one of the one or more conveyors 15 is positioned to extend over the calendaring means 13.

[0257] Furthermore, the configuration of the apparatus 100 according to the present invention, as described above, enables a new process for manufacturing nonwoven fabric articles.

[0258] This process is, of course, carried out by the device 100.

[0259] Therefore, this process advantageously includes at least one transport stage.

[0260] During the conveying phase, preferably, each layer is conveyed separately from the other layers from the exit 10a to the calendaring means 13. Therefore, different layers are only superimposed at the calendaring means 13 due to the different paths preferentially defined by the conveyor 15.

[0261] More specifically, advantageously, during the transport stage, the layers may also be compacted by the compaction means 14 and, in some cases, punched to form punch holes distributed on the layers, where the filaments are interwoven and sealed to one another.

[0262] Therefore, this process, advantageously, also includes a calendar stage.

[0263] During the calendaring stage, multiple layers are calendared together by the calendaring means 13.

[0264] Of course, the present invention also includes nonwoven articles produced by the process described above.

[0265] In a further inventive embodiment of the apparatus 100, the apparatus 100 preferably includes a booth 10 and an additional plant within the booth 10.

[0266] In fact, preferably, booth 10 includes at least two plants distributed parallel to the main plane 1b. Of the two plants, preferably only one is of the spunbond or meltblown type.

[0267] Therefore, based on this configuration, at least two different types of filaments extruded from the plant will be mixed simultaneously at the outlet 10a within the booth 10.

[0268] In this way, different types of filaments produce one identical layer at the output of booth 10.

[0269] This is particularly important because, in typical equipment, different filaments are not mixed before leaving booth 10, but instead are continuously stacked on the collection surface 11 using multiple booths with a single placement device.

[0270] In a particularly advantageous embodiment, preferably, the booth 10 includes at least three plants distributed parallel to the main plane 1b such that at least three filaments, of which at least two are of different types, are mixed simultaneously within the booth 10.

[0271] Therefore, the plant in booth 10 can be configured in various ways.

[0272] First, one or more distribution directions 4a of each plant are either parallel to the distribution plane 100a or can converge to the distribution plane 100a. This means, for example, in a device 100 having three plants, those plants may include a central plant whose distribution direction 4a is parallel to or aligned with the distribution plane 100a, and side plants whose distribution direction 4a converges toward the distribution plane 100a and is therefore incident on and inclined with respect to the distribution direction 4a of the central plant.

[0273] Of course, since the plant can extrude multiple filaments, and the extrusion can be linear or conical, each plant can define a distribution cone in which the distribution direction 4a is confined, for example, as shown in Figures 9a to 9f.

[0274] Furthermore, the plant can define a specific type of configuration.

[0275] For example, in the embodiments shown in Figures 7 and 9a, booth 10 may include a spunbond type plant, a meltblown type plant, and a spunbond type plant in that order. This configuration makes it possible to obtain an SMS type layer by simultaneous blending of filaments, which is particularly advantageous for diaper production.

[0276] Alternatively, in the embodiments shown in FIGS. 9b to 9e, the booth 10 may include a cellulose or viscose distribution plant, a spunbond or meltblown type plant, and a cellulose or viscose distribution plant in that order.

[0277] The cellulose or viscose distribution plant is already known per se, similar to a general meltblown and spunbond plant, and thus will not be described in detail here.

[0278] With this configuration, it becomes possible to obtain an absorbent layer by co-spinning filaments, which is particularly advantageous for the production of wet tissues or the like.

[0279] Alternatively, further, in the embodiment shown in FIG. 9f, the booth 10 may include a meltblown or spunbond type plant, a cellulose or viscose distribution plant, and a meltblown or spunbond type plant in that order.

[0280] If there is one or more meltblown plants in the booth 10, one of them may be of the cusp type (FIG. 9a) or the multi-loop coaxial type (FIGS. 9e to 9f).

[0281] Furthermore, if there is one or more spunbond type plants in the booth 10, they are preferably, but not necessarily, configured as the plant 1 according to the present invention.

[0282] With the configuration of the apparatus 100 according to the present invention described above, a new process for producing non-woven articles becomes possible.

[0283] This process is, of course, carried out by the apparatus 100.

[0284] Therefore, this process advantageously includes at least one mixing step.

[0285] In the mixing stage, preferably, at least two separate filaments distributed from the plant are mixed simultaneously at the outlet 10a of the booth 10.

[0286] As mentioned earlier, it is also possible to mix three filaments at the same time.

[0287] This process then includes a distribution stage, in which single layers, created by mixing different types of filaments, are distributed from the booth 10 through the outlet 10a.

[0288] Therefore, this process includes a deposition stage. In the deposition stage, the layers are collected on a collection surface 11 or on a reel. Thus, the deposited layers enable the creation of nonwoven articles with significantly improved mechanical properties.

[0289] Of course, the present invention also includes articles produced by the process described above.

[0290] The apparatus 100 according to the present invention can also have different configurations.

[0291] For example, the apparatus 100 may include only the booth 10 described, a collection surface 11, and one plant, configured to distribute at least one filament of a selected type, from polymer, cellulose, or viscose, toward an outlet 10a along one or more distribution directions 4a traversing a main plane 1b.

[0292] All of these features have already been explained in detail above.

[0293] However, in a further embodiment of the invention, the apparatus 100 may also include a transport station 12.

[0294] In this case, the transport station 12 is preferably located between the booth 10 and the collection surface 11. In particular, in a preferred embodiment, the transport station 12 is also located next to the outlet 10a, advantageously to seal the outlet 10a.

[0295] Alternatively, in another embodiment, and even in combination with the previous embodiment, the transport station 12 is positioned next to the collection surface 11.

[0296] Therefore, the transport station 12 includes at least one rolling element 12a.

[0297] The rolling elements 12 are preferably aligned parallel to the main plane 1b. Therefore, the rolling elements 12 preferably rotate around an oriented axis of rotation that is parallel, perpendicular, or oblique to the main spindle 1a. Thus, advantageously, the rolling elements 12a are configured to regularly transport the filaments of the filament layer onto the collection surface 11, particularly by oriented the filaments perpendicular or parallel to the collection surface 11.

[0298] Of course, the rolling element 12a can be fixed to the main shaft 1a or selectively rotated.

[0299] Furthermore, the rolling element 12a may include or consist of a first roller 13a or a second roller 14a.

[0300] The rolling element 12a more specifically includes an additional contact surface 120. The contact surface 120 may also include, or consist of, a first contact surface 130 and a second contact surface 140.

[0301] The additional contact surface 120 is part of a second rolling element 12a that is suitable for contacting the filament exiting the booth 10.

[0302] Therefore, the additional contact surface 120 can be smooth.

[0303] Alternatively, the further contact surface 120 may include one or more lourettes. When lourettes are present, the lourettes are configured to pick up the filament from the outlet 10a along the dispensing plane 100a when the filament contacts the further contact surface 120. Further, when lourettes are present, the lourettes are also configured to regularly release the filament when the layer is released from the further contact surface 120.

[0304] In a particularly advantageous embodiment of the device 100, the further contact surface 120 preferably includes a plurality of additional needles 121. The additional needles 121 may also correspond to the first needle 131 or the second needle 141.

[0305] When present, the additional needles 121 are distributed radially around the axis of rotation along the axis of rotation. Further, the additional needles 121 project from the additional contact surface 120.

[0306] Therefore, on the premise of this structure, the additional needles 121 are configured to punch the non-woven fabric layer discharged from the outlet 10a to form punches distributed on the layer. Advantageously, in the punches, the filaments are woven together and sealed.

[0307] The conveying station 12 of the device 100 can also be configured in various ways.

[0308] For example, in the first embodiment shown in FIGS. 8a-8b and FIGS. 9a-9f, the conveying station 12 preferably includes at least a pair of mutually reversely rotating rolling elements 12a. Further, the rolling elements 12a are configured to pass between the rolling elements 12a before the layer is deposited on the collecting surface 11.

[0309] In a further embodiment, as shown in FIGS. 8b, 9a and 9e, the conveying station 12 may include two pairs of rolling elements 12a.

[0310] Furthermore, the pair of rolling elements 12a may include the same additional contact surface 120. Alternatively, as in the embodiment of Figure 9d, the pair of rolling elements 12a may include various additional contact surfaces 120, in particular, for example, smooth and including needles, and even smooth and knurled, or knurled and including needles.

[0311] In embodiments having a single rolling element 12a, particularly when the rolling element 12a is positioned near the collection surface 11 as shown in Figure 8c, the rolling element 12a preferably includes an additional contact surface 120 with additional needles 121.

[0312] In conclusion, the apparatus 100 described above may also include a calendar means 13.

[0313] If a calendaring device 13 is present, the calendaring device 13 is located downstream of the transport station 12.

[0314] Next, the calendar means 13 interacts with the nonwoven fabric layer on the collection surface 11 to produce a nonwoven fabric article.

[0315] The configuration of the apparatus 100 according to the present invention, as described above, enables a new process for manufacturing nonwoven fabric articles.

[0316] This process is, of course, carried out by the device 100.

[0317] Therefore, this process favorably includes at least one distribution stage.

[0318] In the distribution stage, preferably, layers of filaments of a type selected from polymer, cellulose, or viscose are distributed from the outlet 10a along the distribution plane 100a.

[0319] Next, this process also includes, advantageously, a transport stage.

[0320] During the transport phase, the layered filaments are transported onto the collection surface 11 by orienting the filaments perpendicular or parallel to the collection surface 11, passing through the transport station 12 in a regular manner.

[0321] More specifically, advantageously, during the conveying stage, the layers are similarly punched to form punch holes distributed on the layers, where the filaments are interwoven and sealed together.

[0322] Next, this process also includes a deposition stage. In the deposition stage, preferably, layers are deposited on the collection surface 11 so that articles are obtained.

[0323] If a calendar 13 is also present, the process also includes a calendaring step downstream of the conveying station 12, in which layers are calendared to obtain the goods.

[0324] Of course, the present invention also includes nonwoven articles produced by the process described above.

[0325] A plant 1 for producing nonwoven fabrics, an apparatus 100 for producing nonwoven fabrics, a process for producing nonwoven articles, and nonwoven articles according to the present invention achieve significant advantages.

[0326] In fact, conventional spunbond plants typically cannot accommodate spindles that are too wide, because the air delivered to the filament only at the spindle outlet and laterally does not reach the center of the fiber. As a result, the uncooled fibers stick together or drip from the spindle without crystallizing, causing significant damage to the product quality.

[0327] In contrast, Plant 1 can also cool the filament inside the spinneret 4, which allows for more effective and efficient cooling of the fiber, and most importantly, more uniform cooling.

[0328] Therefore, plant 1 can increase the number of fibers extruded from the spinneret 4, and thus significantly increase the number of kilograms of filaments produced compared to current technology. Furthermore, considering that in prior art spunbond plants, cooling air reaches the filament from the side and theoretically can reach the center of the spinneret, the polymer fluid outlet hole layout must always necessarily have the holes offset from each other and spaced sufficiently apart so that the air can reach the center.

[0329] In contrast, in plant 1, the filament can be cooled from above, and therefore, multiple extrusion holes, and in some cases multiple spinnerets 4, can be arranged using various extrusion techniques, such as arranging spunbond spinnerets and meltblown spinnerets side by side and having them cooperate to simultaneously form a single layer on the same plant 1.

[0330] Regarding apparatus 100, in typical known technologies, when attempting to produce nonwoven fabric for use in diaper production, five layers of nonwoven fabric must be laminated together and then all five must be calendered together. The machine requires five different pieces of equipment, each equipped with at least three plants with spunbond-type spinnerets and one plant with a meltblown-type spinneret. As can be imagined, this results in more nonwoven fabric layers being laminated and calendered together, leading to increased product costs due to a decrease in the mechanical quality of the final product.

[0331] Instead, the apparatus 100 according to the present invention allows two or three plants to be arranged side by side, either as a single unit or with separate components, enabling simultaneous operation with multiple spinnerets of various types, and thus having the potential of three apparatus heads of the prior art in the same booth 10, significantly reducing the costs of investment, maintenance, and electricity and air consumption.

[0332] Furthermore, before leaving booth 10, mixing various types of filaments, such as SMS type filaments, simultaneously significantly improves the quality of the product, dramatically altering both its technical and mechanical properties and aesthetic characteristics.

[0333] Furthermore, if there is a cellulose or viscose dispensing plant equipped with a conveyor or editor from which cellulose and / or viscose or other materials emerge, and a polymer filament dispensing plant from which cellulose and / or viscose merge and mix as they emerge, the apparatus 100 enables the production of a single-layer fabric composed of partly polymer fibers and partly of cellulose and / or viscose, cotton, or other materials.

[0334] In conclusion, while known devices can produce items with good mechanical strength in only one direction, device 100, using the transport station 12, can also orient the filament to deposit on the collection surface 11 not only in one direction, but in some cases in different directions, for example, obliquely to the feeding direction of the collection surface 11. This variety of positions of the filament before passing under the calendar allows the formed layer to have increased mechanical strength in both directions.

[0335] Furthermore, having a conveying station 12 in which at least one rolling element 12a includes an additional needle 121 makes it possible to orient the filaments and, at the same time, perforate the layers formed by the filaments so as to partially seal them together before passing under the calender. This makes it possible to provide additional mechanical strength to both sides of the thus fabricated article.

[0336] In conclusion, the apparatus 100, which allows filament layers to be transported without accumulating on the collection surface and different filaments to be transported along separate paths, and as a result, allows calendering without already individually compacted layers accumulating on other layers, enables the production of nonwoven articles with superior performance and greater durability, where the layers are stronger and the seals between different layers are firmer, thereby improving the performance of the articles, especially when used to make diapers or wet wipes.

[0337] The present invention can be modified to produce various versions that fall within the scope of the concept of the invention as defined by the claims.

[0338] In this context, all details may be replaced with equivalent elements, and any material, shape, and dimensions may be used.

Claims

1. The present invention comprises a plurality of separate plants, each configured to produce a nonwoven fabric that unfolds along a main axis and a main plane, and to distribute a plurality of polymer, cellulose, or viscose filaments through an outlet along or parallel to a distribution plane that transverses the main axis and the main plane, forming each layer of filaments from the outlet; Located downstream of the aforementioned outlet, A calendering means configured to perform calendering together with the aforementioned layer, and Each is characterized by including a conveying station, which includes one or more conveyors, each positioned between the respective outlet and the calendering means, and configured to transport each layer separately from the other layers to the calendering means, such that the layers are stacked only in the calendering means. A device for manufacturing nonwoven fabrics.

2. The apparatus according to claim 1, wherein the conveying station is located downstream of one or more of the outlets and between the outlets and the calendering means, and comprises a compaction means configured to compress the layer and weave the filaments of the layer together to seal it before the layer is conveyed to the calendering means.

3. The apparatus according to claim 2, wherein one or more conveyors are arranged between the compaction means and the calendering means.

4. The apparatus according to claim 1 or 2, wherein each of the one or more conveyors includes a collection surface that extends laterally with respect to the distribution plane downstream of the outlet, collects the layer discharged from the outlet, and transports the layer to the calendering means.

5. The apparatus according to claim 1 or 2, wherein the calendering means is positioned at a distance from at least one of the one or more conveyors, and at least one of the one or more conveyors is cantilevered from the calendering means.

6. The apparatus according to claim 1 or 2, wherein the calendaring means comprises at least a pair of counter-rotating first rollers configured to rotate around their respective axes of rotation, which are unfolded parallel to the main plane and oriented relative to the main axis, and to convey the layers out of the outlet under pressure.

7. The apparatus according to claim 6, wherein one or more of the first rollers comprises a first contact surface having smooth or one or more knurling, configured to pull the layer out of the outlet when the filament contacts the first contact surface and to regularly release the filament when the layer is released from the first contact surface.

8. The apparatus according to claim 7, further comprising a plurality of first needles configured to punch holes in the layer of nonwoven fabric distributed from the outlet, such that the first contact surface is distributed radially along and around the rotation axis protruding from the first contact surface, and the punch holes in the layer are distributed on the layer such that the filaments are woven together and sealed.

9. The apparatus according to claim 2 or 3, wherein the compaction means comprises at least a pair of counter-rotating second rollers configured to be deployed parallel to the main plane and rotate around their respective axes of rotation oriented with respect to the main axis, and to convey the layer from the outlet toward the calendering means under pressure.

10. The method comprises distributing multiple layers of filaments of any type, either polymer, cellulose, or viscose, from the outlet along each of the aforementioned distribution planes; Transporting each of the layers from the outlet to the calendering means separately from the other layers, so that the layers are stacked only in the calendering means; and A process for producing a nonwoven fabric item, carried out using the apparatus according to claim 1 or 2, characterized by including calendering the layer using the calendering means.

11. A nonwoven fabric item produced by the process described in claim 10.

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