Classifications

• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/44—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties the fleeces or layers being consolidated by mechanical means, e.g. by rolling
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01G—PRELIMINARY TREATMENT OF FIBRES, e.g. FOR SPINNING
  • D01G15/00—Carding machines or accessories; Card clothing; Burr-crushing or removing arrangements associated with carding or other preliminary-treatment machines
  • D01G15/02—Carding machines
  • D01G15/10—Carding machines with other apparatus, e.g. drafting devices, in integral or closely-associated combination
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01G—PRELIMINARY TREATMENT OF FIBRES, e.g. FOR SPINNING
  • D01G21/00—Combinations of machines, apparatus, or processes, e.g. for continuous processing
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/54—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/732—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by fluid current, e.g. air-lay
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/736—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged characterised by the apparatus for arranging fibres

Definitions

• the invention relates to a system and a method for producing a single- or multi-layer nonwoven fabric.
• the carded fiber rovings are folded in a cross-folder to create a nonwoven with a medium-thickness/thickness ratio (MD/CD) of 1.3:1 to 2.1:1, which is then further consolidated after the cross-folder.
• MD/CD medium-thickness/thickness ratio
• the carding machine produces a fiber roving with a weight of 30 g/ m2 .
• This fiber roving enters a subsequent nonwoven at a speed of, for example, 100 m/min, where it is folded into four layers to achieve the desired MD/CD ratio.
• the multi-layered nonwoven then exits the cross-folder at a speed of, for example, 22 m/min and enters a drafting and consolidation station, before being wound up at a speed of 80 m/min.
• a cross-folder represents a very expensive investment for the plant operator, requiring considerable space due to the L-shaped material flow and undesirably limiting production quality and quantity.
• the WO 2018/055181 A1 reveals a carding process for the aerodynamic production of a fiber fleece with a thermal post-treatment of the nonwoven fabric.
• the EP 3118361 A1 reveals a system for wet-laid fibers that can be operated alone or in combination with a classic carding machine or with a carding fleece only.
• the object of the present invention is to provide a system and a method for producing a single- or multi-layer nonwoven fabric that is flexible in its application and with which almost isotropic nonwoven fabrics can be produced with high productivity.
• the system for producing a single- or multi-layer nonwoven fabric comprises at least one carding machine configured to generate a fiber pile by means of an aerodynamic process, and a first conveyor belt configured to transport the fiber pile from the carding machine to a compaction unit, wherein the compaction unit is configured to compact the fiber pile into a nonwoven fabric.
• an air-laid carding machine can process a wide range of fiber lengths, fiber finenesses, and fiber types.
• the invention provides that a downstream stretching device is arranged in the material transport direction, which is designed to stretch the nonwoven fabric by a factor of at least 1.5. Subsequently, the nonwoven fabric can be consolidated in various ways.
• the system is configured to produce an isotropic nonwoven fabric with high productivity without a lay-up unit.
• the system's productivity is higher than that of a conventional carding machine with a subsequent lay-up unit, and the investment costs are significantly lower.
• productivity can be doubled according to the invention.
• a further advantage is the reduced defect rate in the nonwoven fabric production, since folding thin nonwovens or fiber woven fabrics often results in edge folding, leading to uneven material accumulation across the cross-section.
• the system can include at least one additional carding unit designed to generate another fiber web using an aerodynamic process. If space permits, any number of carding units can be arranged in a row, with their fiber webs being processed together. By varying the number of carding units used and stretching the nonwoven fabric by a factor of 1.5 to 4, the final product can be varied almost arbitrarily in terms of basis weight and productivity.
• the system becomes more flexible and less expensive than a system with a conventional carding unit and lay-up unit. The same or different fiber qualities can be used.
• the conveyor belt for transporting the fiber mat from the first carding machine can be located at least partially beneath the subsequent carding machines.
• the conveyor belt can run underground or be positioned between the supports of the carding machines.
• a separate conveyor belt Prior to compaction, a separate conveyor belt can be installed, designed to collect the fiber piles layered on top of each other. It is not necessary to synchronize this separate conveyor belt with the carding belts' discharge conveyors.
• the carding machines are designed as airlay machines, a compact and space-saving design can be used. Compared to other carding machines that operate on the random lay or aerodynamic principles, the airlay machine can produce a fiber nap with low basis weights and process fibers with a wide range of lengths.
• the compaction unit can, for example, consist of at least one pair of rollers that compact the fiber nap without altering the structure or orientation of the fibers.
• the subsequent stretching unit comprises at least an upper and lower stretching arrangement with which the nonwoven fabric can be stretched by a factor of 1.5 to 4. This arrangement can consist of rollers or conveyor belts, each with a smooth surface, or equipped with needles or pins.
• This unwinding station is designed to introduce, for example, another carded nonwoven fabric or a layer of paper or tissue into the system below and/or above the nonwoven fabric. This results in a highly flexible system in which various fibers with different fiber lengths and basis weights can be introduced and processed individually or together.
• the subsequent bonding process can be implemented as hydrodynamic bonding or as thermal bonding.
• Hydrodynamic bonding is a water jet bonding process and features multiple water jets with an associated suction system, which can be operated at a pressure of 40 to 400 bar.
• a single nonwoven fabric or multiple layers of nonwoven fabric can be bonded, joined, and/or structured.
• an upper structuring belt By means of a specially designed nozzle arrangement or in combination with an upper structuring belt, which compartmentalizes the web as fiber material and/or the nonwoven fabric, structuring and thus creating a patterned surface of the nonwoven fabric is possible.
• bonding and structuring can also be carried out on a drum (not shown) with a mounted structuring tray, which is positioned upstream of the dryer.
• a dryer After hydrodynamic solidification, a dryer can be arranged in the material transport direction.
• the inventive method for producing a single- or multi-layer nonwoven fabric involves generating at least one fiber nap with an MD/CD ratio of 1.0:1 to 1.2:1 from fibers with a fiber length of 10 to 60 mm and a fiber fineness of 0.5 to 30 dtex using an aerodynamic process.
• the fiber nap is subsequently compacted, and the resulting nonwoven fabric is stretched by at least a factor of 1.5 and then bonded.
• the inventive method enables the production of an isotropic nonwoven fabric without a lay-up unit, with high productivity. By stretching the nonwoven fabric, an isotropic nonwoven fabric with virtually any basis weight can be produced at high production speeds.
• the process complexity is significantly lower, and a greater variety of fibers with respect to length, fineness, and grade can be processed.
• the productivity of the system can be further increased. Any number of fiber layers can be produced separately, stacked on top of each other, and adjusted to the final weight via stretching. The concept is essentially limited only by the space required when more than four carding machines are used in a line.
• the superimposed fiber filaments all preferably exhibit the same properties as the first fiber filament.
• the invention also provides for the possibility of producing and processing fiber filaments of different fiber qualities together, with both fiber filaments exhibiting approximately the same isotropy.
• the stretching of the fiber pile can be done by a factor of 1.5 to 4, preferably by a factor of 2.
• the fiber pile of each carding machine can have a basis weight of 20 to 400g/ m2 and be produced at a speed of 15 to 200m/min, preferably having a basis weight of 80g/ m2 and being produced at a speed of 80m/min.
• the process can be made even more flexible by bonding the drawn nonwoven fabric together with at least one other nonwoven fabric, which is fed into the system via an unwinding station.
• the additional nonwoven fabric which could be, for example, a carded nonwoven or a layer of paper or tissue, can be positioned above and/or below the drawn nonwoven fabric.
• the drawn nonwoven fabric can thus be bonded with a different, preferably made of lighter nonwoven fabric, covered on one side or chambered, so that a wide range of products, for example hygiene products, can be manufactured.
• the consolidation of the stretched nonwoven fabric, alone or in combination with the nonwoven fabric(s) introduced from the unwinding station(s), can be carried out hydrodynamically or thermally, depending on the fiber type.
• the system 100 comprises at least one first carding unit 1, which may be designed as an airlay carding unit.
• the carding unit 1 is fed via a feeder 2 with fibers or fiber flakes, which may consist of natural or synthetic fibers (cotton, viscose, lyocell, hemp, pulp, polyester, polyamide, polypropylene, polyolefin) or of mixtures of these fibers.
• fibers with a length of 10 to 60 mm and a density of 0.5 to 30 dtex can be processed.
• the working width of the carding unit 1 can be between 1.5 and 3.8 m.
• the produced fiber pile 3 which, for example, has a weight of 80 g/ m2 at a production speed of 80 m/min, is laid down on a first conveyor belt 4, which guides the fiber pile 3 to a compaction unit, which in this embodiment is designed as a pair of rollers 6.
• the compaction process has the task of densifying the fiber pile without changing the structure in the orientation of the fibers.
• Airlay carding has the advantage that fibers of varying lengths and types (natural/synthetic fibers) can be processed with high quality across a wide range of properties (nonwoven weight, fiber fineness).
• compaction can also be achieved using a roller and a circulating belt, the roller then preferably being designed as a perforated sheet roller.
• Another alternative for compaction is hydromechanical pre-compaction, which has the advantage that the slightly pre-compacted nonwoven fabric can be drawn more uniformly later.
• the system 100 has at least one additional carding unit 1a, which can also be designed as an airlay carding unit.
• the fiber web 3 from the first carding unit 1 is guided by the conveyor belt 4 under the subsequent carding units 1a in the material transport direction and transferred to a further conveyor belt 5.
• the second carding unit 1a is also fed via a feeder 2a with fibers or fiber flakes, which can be identical to the fibers of the first carding unit 1.
• the fibers can also be different, so that a multi-layered nonwoven fabric with layers of different fibers can be produced.
• the produced second fiber web 3a also has a weight of 80 g/ m2 at a production speed of 80 m/min.
• the second fiber web 3a is also transferred to the conveyor belt 5, on which the two fiber webs 3 and 3a are brought together. Synchronization of the conveyor belts 4, 5 is not necessary.
• the subsequent compaction unit into which two layers of fiber 3, 3a with a total weight of 160 g/ m2 enter at 80 m/min, is designed in this embodiment as a pair of rollers and compacts the two layers of fiber 3, 3a without changing the orientation of the fibers, thus forming a nonwoven fabric 24. Since the final product is to have a weight of 40 g/ m2 , a stretching device 10, which can be designed as a nonwoven fabric stretcher, is arranged after the compaction unit.
• the pre-drawing device 10 is designed as a nonwoven stretcher, which may have an entry area 11 with two conveyor belts angled relative to each other. The angle of the conveyor belts can be adjusted, as can the speed of each individual conveyor belt.
• the nonwoven fabric 24 is pre-compressed and its thickness reduced so that it can enter between the upper and lower pre-drawing arrangements 12, 13.
• Both pre-drawing arrangements 12, 13 consist of a series of rollers that are offset from each other, such that the rollers of the upper pre-drawing arrangement 12 project at least partially into the gusset of the rollers of the lower pre-drawing arrangement 13.
• At least some of the rollers are driven, with the two pre-drawing arrangements 12, 13 being operated at different roller speeds, so that the nonwoven fabric is stretched between the rollers.
• the rotational speed of the rollers can increase continuously from the inlet area 11 to the outlet area 14.
• the rollers preferably have individual drives, so that the drafting along the drafting device can be variably adjusted.
• the mass of the nonwoven fabric 24 in the cross-section can be reduced by the speed difference of the rollers from the inlet area 11 to the outlet area 14, so that the nonwoven fabric 24 is stretched essentially uniformly over its entire cross-section.
• the upper drafting arrangement 12 is force- or weight-loaded.
• the distance between the upper drafting arrangement 12 and the lower drafting arrangement 13 can decrease from the inlet area 11 to the outlet area 14.
• the discharge area 14 of the delay device 10 can be designed as a conveyor belt adapted to the increased transport speed of the nonwoven fabric.
• the surfaces of the rollers of the upper and lower winding arrangement 12, 13 can be smooth or have a set of pins, which prevents shrinkage of the nonwoven fabric. Lateral guides on the winding device 10 prevent the nonwoven fabric 24 from being stretched beyond the desired working width.
• Figure 2b shows a second embodiment of a pre-drawing device 10, which can also have an infeed area 11 with two conveyor belts angled relative to each other.
• the angle of the conveyor belts relative to each other can be adjusted, as can the speed of each individual conveyor belt.
• the nonwoven fabric 24 is pre-compressed and its thickness reduced so that it can enter between the upper and lower pre-drawing arrangements 12, 13.
• the upper and lower pre-drawing arrangements 12, 13 are designed as conveyor belts, with the conveyor belts operating at different speeds, so that the nonwoven fabric is stretched between the conveyor belts by a factor, which can be, for example, 2.
• the angle and/or distance between the upper and lower pre-drawing arrangements 12, 13 can also be adjusted to accommodate different nonwoven fabric thicknesses.
• the discharge area 14 is designed as a conveyor belt and can be adjusted to different speed ranges according to the stretching factor.
• the conveyor belts of the drafting arrangement 12, 13 can also be provided with needles on the surface facing the nonwoven fabric 24.
• the nonwoven fabric 24 which has been stretched by a factor of 2 in the pre-drawing unit 10, for example, is consolidated with a weight of 40 g/ m2 at a speed of 160 m/min.
• This consolidation can take place in the subsequent hydrodynamic consolidation.
• This consolidation has several water bars 20 in which the fibers are interwoven by means of water jets.
• a circulating conveyor belt 21 can be arranged below the water bars 20, and a suction unit 22 is located below it.
• the conveyor belt 21 is perforated to drain the water from the water bars 20.
• the nonwoven fabric 24 can also be chambered between two conveyor belts and consolidated by means of water jets.
• the nonwoven fabric can not only be consolidated but can also be structured and/or perforated.
• Another alternative to this embodiment can be achieved by consolidation on a rotating drum with internal suction, in which the nonwoven fabric 24 is located next to the The bonding process also structures and/or perforates the material.
• the water beams can be operated with a water pressure of 40–400 bar.
• the nonwoven fabric 24 is dried in a dryer, which can be a drum or belt dryer, and wound up at a winding station 25.
• FIG. 3 An alternative embodiment of Annex 100 is in Figure 3
• the diagram shows a system in which at least one or two unwinding stations 15 are arranged downstream of the warping unit 10. These stations are designed to feed, for example, a thin layer of synthetic carded nonwoven fabric 15a into the system below and/or above the nonwoven fabric 24, so that the nonwoven fabric 24, made of isotropic fibers, is covered with one or two further layers of carded nonwoven fabric 15a.
• the layers of thin synthetic carded nonwoven fabric 15a can, for example, have a low basis weight of ⁇ 30 g/ m2 .
• a thin nonwoven fabric made of tissue or paper can also be used.
• the system is configured to produce a single- or multi-layered nonwoven fabric 24, which can consist solely of the fiber nap 3, 3a of the carding 1, 1a, or of the fiber nap 3, 3a with a lower and/or upper carding nap 15a.
• a single- or multi-layered nonwoven fabric 24 can consist solely of the fiber nap 3, 3a of the carding 1, 1a, or of the fiber nap 3, 3a with a lower and/or upper carding nap 15a.
• the system 100 is configured such that an isotropic nonwoven fabric 24 can be produced with high productivity without a lay-up unit.
• the MD/CD ratio after bonding is between 1.5:1 and 2.1:1.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Mechanical Engineering (AREA)
• Nonwoven Fabrics (AREA)
• Preliminary Treatment Of Fibers (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=83995557

Family Applications (1)

Country Status (6)

Citations (1)

Family Cites Families (14)

• 2021
  • 2021-12-06 DE DE102021132077.1A patent/DE102021132077A1/de active Pending
• 2022
  • 2022-09-22 CN CN202280042000.0A patent/CN117500966A/zh active Pending
  • 2022-09-22 JP JP2024513853A patent/JP2024541171A/ja active Pending
  • 2022-09-22 EP EP22793716.6A patent/EP4444946B1/de active Active
  • 2022-09-22 PL PL22793716.6T patent/PL4444946T3/pl unknown
  • 2022-09-22 WO PCT/EP2022/076383 patent/WO2023104365A1/de not_active Ceased

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Non-Patent Citations (1)

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