Hydro-entangled filter material for smoking articles with improved expansion properties

Abstract

The invention relates to a hydroentangled nonwoven for producing segments of smoking articles, wherein the hydroentangled nonwoven is in the form of a web and contains at least 50% and at most 100% of cellulosic fibers, in each case based on the mass of the hydroentangled nonwoven, wherein the hydroentangled nonwoven has a weight per unit area of at least 15 g / m 2 and at most 60 g / m 2 , wherein the hydroentangled nonwoven has a machine direction and a transverse direction which is orthogonal thereto and which lies in the plane of the web of the hydroentangled nonwoven, and wherein the hydroentangled nonwoven has a characteristic plastic deformability in the transverse direction, characterized in that the nonlinear portion of the deformation energy absorbed by the hydroentangled nonwoven up to half the breaking elongation in a tensile test in the transverse direction according to ISO 1924-2:2008 is at least 10% and at most 50% of the total deformation energy absorbed by the hydroentangled nonwoven up to half the breaking elongation.

Description

Invention Field

[0001] This invention relates to filter materials suitable for use in the manufacture of sections in smoking articles, said filter material having advantageous plastic deformability in the transverse direction, thereby enabling the efficient manufacture of sections for smoking articles. The invention also relates to sections for smoking articles manufactured from such filter materials.

[0002] Background and Existing Technology

[0003] Smoking articles are typically rod-shaped articles, consisting of at least two rod-shaped segments arranged adjacent to each other. One segment contains a material capable of forming an aerosol upon heating, and at least one additional segment is used to influence the properties of the aerosol.

[0004] Smoking products can be filter cigarettes, wherein the first section contains aerosol-forming material, particularly tobacco, and the remaining sections are designed as filters to filter aerosols. In this respect, aerosols are generated by the combustion of the aerosol-forming material, and the filters primarily serve to filter aerosols and provide limited draw resistance for filter cigarettes.

[0005] However, smoking products can also be well-known heated tobacco products, in which the aerosol-forming material is heated but not burned. This means a reduction in the types and amounts of harmful substances in the aerosol. Such smoking products also consist of at least two sections, but more often multiple sections, particularly four. One section contains the aerosol-forming material, which typically includes tobacco, reconstituted tobacco, or tobacco prepared by other methods. Additionally, optional sections in heated tobacco products are used to transfer, cool, or filter the aerosol.

[0006] The sections are typically encased in packaging materials. Paper is commonly used as the packaging material.

[0007] Unless explicitly stated below or immediately apparent from the context, “segment” should be understood as a segment of a smoking article that does not contain aerosol-forming materials, but rather a segment used, for example, to transfer, cool, or filter aerosols.

[0008] In the prior art, it is known that such segments are formed from polymers such as cellulose acetate or polylactide. After consumption, smoking products must be properly disposed of. However, in many cases, consumers simply discard used smoking products into the environment, and attempts to curb this behavior through prosecution or fines have had little success.

[0009] Because cellulose acetate and polylactide biodegrade very slowly in the environment, there is industrial interest in manufacturing segments of smoking products from other, more biodegradable materials. Furthermore, regulations are under discussion in the European Union, for example, to significantly reduce or ban the use of non-natural polymers in smoking products, making it also interesting to provide alternative segments for available smoking products for this reason.

[0010] In the prior art, sections, particularly filter sections, made of paper are known for use in smoking products. These sections are generally readily biodegradable, but this also presents disadvantages. For example, filter sections from paper typically have high filtration efficiency, resulting in a dry aerosol, which deteriorates the aerosol flavor compared to cigarettes with conventional filter sections from cellulose acetate. Furthermore, they are generally less efficient at filtering phenol than cellulose acetate.

[0011] The primary reason for the limited use of filter segments from paper to date is their optical appearance. In the mouthpiece of smoking products, the cross-section of the segment located there is visible, and consumers are accustomed to the uniform white surface of conventional segments from cellulose acetate, where individual cut fibers are barely visible. However, segments from paper have a coarse structure, which gives consumers an impression of lower quality. Therefore, segments from paper are typically used only as part of one segment in a filter composed of multiple segments, making the cross-section invisible to the consumer. The mouthpiece segment is still often made of cellulose acetate. Due to these optical defects, the biodegradability of segments from paper cannot be fully utilized.

[0012] Segments for smoking articles made from nonwoven fabrics are also known in the prior art. For example, EP 2 515689 describes filter materials made from nonwoven fabrics; however, these primarily consist of fibers derived from polyvinyl alcohol, polylactide, or other non-natural polymers, and therefore do not fully meet the requirements for biodegradability. Furthermore, the nonwoven fabrics described herein are too thin to produce an optically acceptable appearance at the cross-section of the segments made from them.

[0013] Filter materials for smoking products made from paper are known in the prior art, manufactured from readily biodegradable fibers. Such filter materials are described in US2015 / 0374030; however, they consist to a considerable extent of pulp fibers from hemp, flax, Manila hemp, sisal, or cotton. These fibers are expensive, and their quality varies considerably due to their shorter growth cycle compared to pulp fibers from wood. Following the teachings in US2015 / 0374030, they need to achieve a sufficiently porous structure while simultaneously achieving sufficiently high strength. The use of wood pulp is hindered because it produces a dense and compact paper structure. In fact, the proportion of wood pulp should always be less than 50% by weight, and in industrial implementations, it is less than 5% by weight. Furthermore, due to the manufacturing process used, the optical appearance of such filters is not appealing to consumers.

[0014] Contrary to the teachings of the prior art, the inventors have discovered in this application that filter materials with a high proportion of pulp fibers can be manufactured in the form of a hydraulically entangled nonwoven fabric without making the structure of the nonwoven fabric too dense or too compact. A corresponding filter material that can be considered the starting point of this invention is described in the unpublished international application PCT / EP2019 / 085125. In that unpublished application, the pleating or crimping of the filter material to form a continuous bundle of pleated or crimped filaments is also described, followed by wrapping the segment with packaging paper and cutting it into individual rods of defined lengths.

[0015] As an example, during the manufacturing of a section, the cellulose-based nonwoven web can be initially crimped in the longitudinal direction before the paper web or cellulose-based nonwoven web is formed into a continuous tow and sealed with packaging material. The continuous tow can then be cut into parts suitable for further processing.

[0016] During the winding of the web, the web can pass through two patterned rollers, which imprint the pattern onto the web. As an example, the pattern can be a line pattern oriented along the machine direction of the web. The imprinted lines stretch and deform the web in a direction orthogonal to the machine direction (transverse), thus making it easier to form a continuous bundle of filaments by gathering the web in the transverse direction.

[0017] However, during the pleating process of the described type, tearing of the web in the transverse direction may occur. Therefore, there is a need for a filter material that does not have this disadvantage or has only a minor one, but is otherwise as similar as possible to other preferred filter materials, particularly those described in the aforementioned unpublished application PCT / EP2019 / 085125. Summary of the Invention

[0018] The object of the present invention is to provide a web-shaped filter material for smoking articles, which can be processed into sections of smoking articles with high productivity and is otherwise as similar as possible to preferred filter materials in terms of performance.

[0019] This objective is achieved by the hydraulically entangled nonwoven fabric as claimed in claim 1, the segment for a smoking article as claimed in claim 16, and the smoking article as claimed in claim 23, and by the method for manufacturing the segment as claimed in claim 22 and the method for manufacturing the hydraulically entangled nonwoven fabric as claimed in claim 27. Advantageous embodiments are provided in the dependent claims.

[0020] The inventors have discovered that this objective can be achieved by a filter material for a segment of a smoking article, wherein the filter material is a web-shaped, hydraulically entangled nonwoven fabric. Although the term "hydraulically entangled" primarily refers to the underlying manufacturing process, it should be considered that hydraulically entangled nonwovens possess unique structural properties that distinguish them from other nonwovens, and which, according to the inventors' knowledge, cannot be obtained in the same manner by other manufacturing processes. Unlike, for example, paper (where strength is due to hydrogen bonding and fibers are oriented primarily in the paper plane), the strength of a hydraulically entangled nonwoven fabric is obtained through the entanglement of fibers. The hydraulically entangled nonwoven fabric has a particularly porous structure, making it especially suitable as a filter material for a segment of a smoking article.

[0021] According to the present invention, the hydroentangled nonwoven fabric contains at least 50% and at most 100% cellulose fibers, each relative to the mass of the hydroentangled nonwoven fabric, wherein the hydroentangled nonwoven fabric has a mass of at least 15 g / m³. 2 And at most 60g / m 2 The basis weight. In this respect, the hydraulically entangled nonwoven fabric has a machine direction and a transverse direction orthogonal to the machine direction located in the plane of the web of the hydraulically entangled nonwoven fabric. Furthermore, the hydraulically entangled nonwoven fabric has a unique plastic deformability in the transverse direction, characterized in that, in the tensile test in the transverse direction according to ISO 1924-2:200,8, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 10% and at most 50% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break. This unique plastic deformability is more significant than that of ordinary filter materials.

[0022] During the manufacture and processing of hydraulically entangled nonwovens, the hydraulically entangled nonwovens run through the machine in one direction (the so-called machine direction), and the hydraulically entangled nonwovens have a direction (lateral) orthogonal to the machine direction in the plane of the web of the hydraulically entangled nonwovens.

[0023] During the processing of the filter material into sections for forming smoking articles, the hydraulically entangled nonwoven fabric is preferably crimped. For this purpose, the hydraulically entangled nonwoven fabric is passed, for example, through two patterned rollers that imprint the pattern onto the web. Preferably, the pattern is a line pattern oriented in the machine direction of the web. The imprinted lines stretch and deform the hydraulically entangled nonwoven fabric in a direction orthogonal to the machine direction (transverse). Filter material deformed in this way can be more easily aggregated in the transverse direction, and thus continuous tows can be produced for manufacturing sections.

[0024] One problem with this method is that, in order to induce the desired deformation of the hydraulically entangled nonwoven fabric, the two rollers produce high elongation in the transverse direction of the web, and therefore there is a risk that the hydraulically entangled nonwoven fabric will tear in the transverse direction. Those skilled in the art can now attempt to increase the elongation at break in the transverse direction of the hydraulically entangled nonwoven fabric so that it allows for greater deformation without tearing. However, the inventors have found that this does not solve the problem, because in order to achieve permanent deformation in the transverse direction, the elongation must be further increased, further increasing the risk of exceeding the breaking strength in the transverse direction.

[0025] According to the inventors' findings, and more importantly, during crimping, the lateral elongation of the hydraulically entangled nonwoven fabric exposed induces permanent plastic deformation, rather than elastic deformation. If this plastic deformation can be achieved during crimping with greater separation of the rollers, the risk of lateral tearing of the hydraulically entangled nonwoven fabric during processing is reduced. Typically, lateral stretching of the filter material up to approximately half its elongation at break should be sufficient.

[0026] The inventors have now discovered that, by using a suitable process, hydraulically entangled nonwovens can have a structure that exhibits good plastic deformation in the transverse direction and thus simplifies curling. Therefore, a suitable method is explained further below.

[0027] This transverse plastic deformation can be characterized in a tensile test according to ISO 1924-2:2008. In this tensile test, a strip with a width of 15 mm is removed from the sample transversely and stretched at a speed of 20 mm / min until it breaks. During this process, the elongation ε and the applied force F are recorded, resulting in a force-elongation curve F(ε). Similarly, the elongation at break ε is recorded. b and tensile strength F(ε)b Then, the hydraulically entangled nonwoven fabric absorbs up to half the elongation at break (ε). b / 2 of the deformation energy is

[0028]

[0029] In practice, integrals are calculated using numerical methods.

[0030] The deformation energy consists of an elastic portion and a plastic portion. The elastic deformation energy is released upon removal of the load, thus contributing nothing to the curling result. However, the plastic deformation is irreversible, meaning that even with a small elongation through the two rollers, good curling results can be expected if the portion of the plastic deformation energy relative to the total deformation energy is higher than that of similar filter materials in the prior art.

[0031] Elastic deformation is generally related to the ratio between elongation and force. Under the hypothetical assumption that hydraulically entangled nonwovens exhibit ideal elasticity up to half the elongation at break, the deformation energy E up to half the elongation at break is... lin Calculated using the following formula

[0032]

[0033] Then, the nonlinear portion E of the deformation energy absorbed by the hydraulically entangled nonwoven fabric, up to more than half of the fracture elongation at break, is generated. nl

[0034]

[0035] According to the inventors' discovery, if the nonlinear portion of the absorbed deformation energy up to half the transverse elongation at break is at least 10% of the total absorbed deformation energy up to half the transverse elongation at break, i.e.

[0036]

[0037] Very good results can be achieved during the curling process.

[0038] These considerations for quantifying plastic behavior can be achieved through... Figure 1 The figure shown illustrates the tensile test performed according to ISO 1924-2:2008. The elongation ε is displayed on the x-axis 10, while the force F(ε) applied to cause this elongation is displayed on the y-axis 11. Starting from the stress-free state 12, the elongation ε increases at a rate of 20 mm / min, while the force F(ε) is measured simultaneously, resulting in the force-elongation curve 13. The elongation continues to increase until the sample tears in state 14, and the elongation at break ε is thus determined. band tensile strength F(ε) b ).

[0039] During the manufacturing of sections of hydraulically entangled nonwoven fabric, the hydraulically entangled nonwoven fabric can be in certain locations, for example, up to about half of the elongation at break ε. b / 2(point 15), the corresponding force F(ε) under load b / 2), which makes state 16 possible.

[0040] Line 17, connecting points 12 and 16, represents a hypothetical linear elastic behavior, and the linear deformation energy E lin This corresponds to the region of the triangle formed by points 12, 16, and 15. However, the total deformation energy corresponds to the region enclosed by line 13, which runs from point 12 to point 15, from point 15 to point 16, and from point 16 to point 12. In the context of this invention, the nonlinear portion E is used to characterize the deformation energy of the hydraulically entangled nonwoven fabric according to the invention. n1 Corresponding to the region defined by lines 17 and 13, which are respectively located between points 12 and 16. The more strongly the force-elongation curve bends upward and the more it deviates from the hypothetical linear elastic behavior, the greater the likelihood of plasticity, and therefore the greater the likelihood of irreversible deformation.

[0041] During the manufacture of a section of the hydraulically entangled nonwoven fabric according to the invention, the elongation in the transverse direction can naturally deviate from half of the breaking elongation during the curling period. However, the nonlinear portion of the deformation energy up to half of the breaking elongation, which is independent of the actual applied elongation and the actual elastic-plastic behavior, has been found to be a suitable parameter for characterizing the structure of the hydraulically entangled nonwoven fabric according to the invention and for predicting the behavior of the hydraulically entangled nonwoven fabric during curling.

[0042] For comparison, Figure 2 The behavior of a typical ordinary filter material not according to the present invention is shown. Here, a tensile test according to ISO 1924-2:2008 is also performed on the sample in the transverse direction. The elongation ε is shown on the x-axis 20, and the force F(ε) applied to cause this elongation is shown on the y-axis 21. Starting from the stress-free state 22, the elongation ε increases at a rate of 20 mm / min, and the force F(ε) is measured simultaneously, resulting in a force-elongation curve 23. The elongation thus increases until the sample tears in state 24, and the elongation at break ε is thus determined. b and tensile strength F(ε) b ).

[0043] During the manufacturing of sections of hydraulically entangled nonwoven fabric, the hydraulically entangled nonwoven fabric can, for example, be loaded with a corresponding force F(ε). b / 2) Until approximately half of the elongation at break εb / 2(point 25), so that state 26 is reached.

[0044] Line 27, connecting points 22 and 26, represents linear elastic behavior, and the corresponding deformation energy E lin This corresponds to the region of the triangle formed by points 22, 26, and 25. However, the total deformation energy E corresponds to the region enclosed by line 23, which runs from point 22 to point 25, from point 25 to point 26, and from point 26 to point 22. The nonlinear component of the deformation energy E... n1 Corresponding to the region defined by lines 27 and 23, which are respectively between points 22 and 26. It can be seen that, with very similar elongation at break and very similar linear portions of deformation energy, the portion of nonlinear deformation energy is substantially smaller. Therefore, the response of this hydraulically entangled nonwoven to deformation will be primarily elastic, and upon removal of the load, the entire deformation will essentially be reversed. To introduce... Figure 1 The hydraulically entangled nonwovens shown in the diagram have similar plastic deformation energies as line 28, requiring stretching up to point 29. The required elongation is substantially higher, and initially, the required force approaches the transverse tensile strength. Due to small machine deviations or variations in the mass of the hydraulically entangled nonwovens, tearing may occur transversely. However, from... Figure 1 The hydraulically entangled nonwoven fabric according to the invention has a structure that allows for permanent deformation in the lateral direction even at small elongation rates, thus enabling more reliable manufacture of sections for smoking articles.

[0045] The hydraulically entangled nonwoven fabric according to the invention contains cellulose fibers. According to the inventors' findings, cellulose fibers are necessary to provide sufficient strength to the hydraulically entangled nonwoven fabric, allowing it to be processed into segments. According to the invention, however, the proportion of cellulose fibers in the hydraulically entangled nonwoven fabric is at least 50% and at most 100% of the mass of the hydraulically entangled nonwoven fabric, preferably at least 60% and at most 100%, and particularly preferably at least 70% and at most 95%, relative to the mass of the hydraulically entangled nonwoven fabric.

[0046] Cellulose fibers can be pulp fibers or fibers derived from regenerated cellulose, or mixtures thereof.

[0047] The pulp fibers are preferably derived from coniferous, deciduous, or other plants such as hemp, flax, jute, ramie, kenaf, kapok, coconut, Manila hemp, sisal, bamboo, cotton, or thatch. Mixtures of pulp fibers from various sources can also be used to manufacture hydraulically entangled nonwovens. Particularly preferred are pulp fibers derived from coniferous trees, as these fibers provide good strength for hydraulically entangled nonwovens, even in small proportions.

[0048] The hydroentangled nonwoven fabric according to the invention may contain fibers from regenerated cellulose. Preferably, the proportion of fibers from regenerated cellulose, each relative to the mass of the hydroentangled nonwoven fabric, is at least 5% and at most 50%, particularly preferably at least 10% and at most 45%, and highly preferably at least 15% and at most 40%.

[0049] Fibers derived from regenerated cellulose preferably comprise at least partially, and particularly more than 70%, viscose fibers, modal fibers, fiber, Fibers or mixtures thereof are formed. These fibers are highly biodegradable and can be used to optimize the strength of hydraulically entangled nonwovens and adjust the filtration efficiency of segments made from them for smoking articles. Due to the manufacturing process, they exhibit less variation than pulp fibers from natural sources, and therefore contribute to less variation in the properties of segments made from hydraulically entangled nonwovens compared to the case of using only pulp fibers. However, their manufacture requires more work, and they are generally also more expensive than pulp fibers.

[0050] According to the present invention, the basis weight of the hydraulically entangled nonwoven fabric is at least 15 g / m². 2 And at most 60g / m 2 Preferably at least 18g / m 2 And at most 55g / m 2 And preferably at least 20g / m 2 And at most 50g / m 2 Basis weight affects the tensile strength of hydraulically entangled nonwovens, with higher basis weight generally resulting in higher tensile strength. However, basis weight should not be too high, as hydraulically entangled nonwovens cannot be processed at high speeds into sections for use in smoking articles. This value refers to the basis weight measured according to ISO 536:2019.

[0051] For the hydraulically entangled nonwovens according to the invention, in the transverse tensile test according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwovens up to half the elongation at break is at least 10% and at most 50% of the total deformation energy absorbed by the hydraulically entangled nonwovens up to half the elongation at break. Preferably, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwovens up to half the elongation at break is at least 15% and at most 40% of the total deformation energy absorbed by the hydraulically entangled nonwovens up to half the elongation at break, and particularly preferably, the nonlinear portion is at least 15% and at most 35%, and especially at least 18% and at most 32%. At the preferred and particularly preferred intervals, good results can be obtained even at moderate elongation during crimping, and the risk of tearing in the transverse direction of the hydraulically entangled nonwovens is particularly low.

[0052] To achieve specific properties, the hydraulically entangled nonwovens according to the invention may contain additives such as alkyl ketene dimers (AKD), acid anhydrides such as alkenyl succinic anhydride (ASA), polyvinyl alcohol, waxes, fatty acids, starch, starch derivatives, carboxymethyl cellulose, alginate, chitosan, wet strength agents, or pH-adjusting substances (e.g., organic or inorganic acids or bases). Alternatively or additionally, the hydraulically entangled nonwovens according to the invention may also contain one or more additives selected from citrates such as trisodium citrate or tripotassium citrate, malates, tartrates, acetates such as sodium acetate or potassium acetate, nitrates, succinates, fumarates, gluconates, glycolates, lactates, oxalates, salicylates, α-hydroxyoctanoates, phosphates, polyphosphates, chlorides, and bicarbonates, and mixtures thereof.

[0053] A person skilled in the art can determine the type and amount of such additive based on his experience.

[0054] The hydroentangled nonwovens according to the present invention may further include other substances that are better suited to the filtration efficiency of the hydroentangled nonwovens and the filtration efficiency of cellulose acetate. In a preferred embodiment of the hydroentangled nonwovens according to the present invention, the hydroentangled nonwovens include substances selected from triacetin, propylene glycol, sorbitol, glycerol, polyethylene glycol, polypropylene glycol, polyvinyl alcohol, triethyl citrate, or mixtures thereof.

[0055] In a preferred embodiment of the hydraulically entangled nonwoven fabric, at least a portion of the cellulose fibers is loaded with filler, wherein the filler is particularly preferably formed of mineral particles, and especially of calcium carbonate particles. Because the structure of the hydraulically entangled nonwoven fabric is highly porous, it is not suitable for retaining filler, making it advantageous to load the cellulose fibers with filler and thus retain them within the structure of the hydraulically entangled nonwoven fabric. The filler can be used to impart specific properties to the hydraulically entangled nonwoven fabric.

[0056] The thickness of a single layer of hydraulically entangled nonwoven fabric, as measured according to ISO 534:2011, is preferably at least 25 μm and at most 1000 μm, preferably at least 30 μm and at most 800 μm, and particularly preferably at least 35 μm and at most 600 μm. Thickness affects the amount of hydraulically entangled nonwoven fabric that can be incorporated into sections of a smoking article, and thus affects the suction resistance and filtration efficiency of the section, as well as the processability of the hydraulically entangled nonwoven fabric, especially if it is curled or wrinkled during the manufacture of the section for use in the smoking article. For such a process step, excessive thickness is disadvantageous, and thicknesses within the preferred and particularly preferred intervals allow for particularly good processability of the hydraulically entangled nonwoven fabric according to the invention for forming sections of a smoking article.

[0057] The mechanical properties of the hydraulically entangled nonwoven fabric are important for processing sections of the hydraulically entangled nonwoven fabric according to the invention into smoking articles. The tensile strength of the hydraulically entangled nonwoven fabric relative to the width in the transverse direction, as measured according to ISO 1924-2:2008, is preferably at least 0.05 kN / m and at most 5 kN / m, particularly preferably at least 0.07 kN / m and at most 4 kN / m.

[0058] Therefore, the elongation at break of hydraulically entangled nonwovens, as measured according to ISO 1924-2:2008, is preferably at least 0.5% and at most 50%, and particularly preferably at least 0.8% and at most 40%. The elongation at break is primarily determined by the length of the fibers, with longer fibers resulting in a higher elongation at break, and thus it can be adjusted within a wide range according to the specific requirements of the hydraulically entangled nonwovens.

[0059] The segments for smoking articles according to the invention can be manufactured from the hydraulically entangled nonwoven fabric according to the invention using methods known in the art. These methods include, for example, crimping the hydraulically entangled nonwoven fabric, forming a continuous tow from the crimped hydraulically entangled nonwoven fabric, encapsulating the continuous tow with packaging material, and cutting the encapsulated tow into individual rods of defined lengths. In many cases, the length of such rods is an integer multiple of the length of the segments subsequently used in the smoking articles according to the invention, and therefore, the rods are cut into segments of desired lengths before or during the manufacture of the smoking articles.

[0060] The section for smoking articles according to the invention includes the hydraulically entangled nonwoven fabric and packaging material according to the invention.

[0061] Specifically, the segment includes a hydraulically entangled nonwoven fabric aggregated in the transverse direction, and packaging material, wherein, relative to the mass of the hydraulically entangled nonwoven fabric, the hydraulically entangled nonwoven fabric contains at least 50% and at most 100% cellulose fibers. In this respect, the hydraulically entangled nonwoven fabric has a mass of at least 15 g / m³. 2 And at most 60g / m 2 The basis weight. To determine the basis weight, the area of ​​the hydraulically entangled nonwoven fabric is used if the nonwoven fabric is laid out (i.e., no longer aggregated). The hydraulically entangled nonwoven fabric has a transverse direction in which it aggregates. To facilitate the aggregation of the hydraulically entangled nonwoven fabric, it can be pre-formed by crimping or pleating. Therefore, the term "aggregate" should be interpreted broadly, and the verb "aggregate" does not imply that the "aggregated" state is achieved by any particular mechanical method. Furthermore, the "pleated" state, for example, in the context of this disclosure, is the "aggregated" state, unrelated to the mechanical means of achieving pleating or shortening in the transverse direction. Furthermore, in the non-aggregated state, the hydraulically entangled nonwoven fabric exhibits unique plastic deformation properties in the transverse direction, characterized in that, in the transverse tensile test according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 10% and at most 50% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break.

[0062] In a preferred embodiment of the segment according to the invention, the segment is cylindrical with a diameter of at least 3 mm and at most 10 mm, particularly preferably at least 4 mm and at most 9 mm, and even more particularly preferably at least 5 mm and at most 8 mm. These diameters are advantageous for use in smoking articles according to the invention.

[0063] In a preferred embodiment of the segment according to the invention, the segment has a length of at least 4 mm and at most 40 mm, particularly preferably at least 6 mm and at most 35 mm, and even more particularly preferably at least 10 mm and at most 28 mm.

[0064] To generate a certain volumetric flow rate through a smoking product, the draw resistance of a section specifically determines the pressure differential that the consumer needs to apply during use, and therefore substantially affects the consumer's acceptance of the smoking product. The draw resistance of a section can be measured according to ISO 6565:2015 and given in mm water level gauges (mmWG). For a very good approximation, the draw resistance of a section is proportional to the length of the section, so that the measurement of draw resistance can also be performed on a rod that differs only in its length from the section. The draw resistance of the section can then be easily calculated.

[0065] The suction resistance per unit length of the section is preferably at least 1 mmWG / mm and at most 12 mmWG / mm, and particularly preferably at least 2 mmWG / mm and at most 10 mmWG / mm.

[0066] The packaging material for the sections according to the invention is preferably paper or film.

[0067] The packaging material for the segment according to the invention preferably has a content of at least 20 g / m³ according to ISO 536:2019. 2 And at most 150g / m 2 Particularly preferred is at least 30g / m 2 And at most 130g / m 2 The basis weight. Packaging materials having this preferred or particularly preferred basis weight provide a particularly advantageous rigidity to the sections of the invention encapsulated by them.

[0068] The smoking articles according to the present invention can be manufactured from the sections according to the present invention using methods known in the art.

[0069] The smoking article according to the invention includes a segment containing an aerosol-forming material and a segment containing a nonwoven and packaging material with hydraulic entanglement according to the invention.

[0070] Because the cross-section of the segment according to the invention is optically very similar to the cross-section of a segment made of cellulose acetate, in a preferred embodiment, the segment located near the mouthpiece of the smoking article is the segment according to the invention.

[0071] In a preferred embodiment, the smoking product is a filtered cigarette, and the aerosol-forming material comprises tobacco.

[0072] In a preferred embodiment, the smoking article is one in which the aerosol-forming material is heated but not burned during its intended use, and the aerosol-forming material preferably comprises a material selected from tobacco, recycled tobacco, nicotine, glycerin, propylene glycol, or mixtures thereof. Here, the aerosol-forming material may also be in liquid form and may be located in a suitable container within the smoking article.

[0073] According to the inventors' discovery, the nonlinear portion of the deformation energy according to the invention can be obtained by more strongly orienting the fibers in the hydraulically entangled nonwoven fabric in the machine direction of the hydraulically entangled nonwoven fabric. This can be achieved by the method according to the invention described below.

[0074] The hydraulically entangled nonwoven fabric according to the present invention can be manufactured according to the method including steps A1 to A3.

[0075] A1 – Provides a fiber web comprising cellulose fibers having a machine orientation and a transverse orientation orthogonal to the machine orientation in the plane of the fiber web.

[0076] A2 – To produce a hydraulically entangled fiber web by guiding a water jet onto the fiber web.

[0077] A3 – Dry, hydraulically entangled fiber webs

[0078] In step A1, the amount or proportion of cellulose fibers in the fiber web is selected such that, after drying in step A3, the hydroentangled nonwoven fabric contains at least 50% and at most 100% cellulose fibers relative to the mass of the hydroentangled nonwoven fabric.

[0079] The steps A1 and A2 are performed to provide the hydraulically entangled nonwoven fabric with a characteristic plastic deformability in the transverse direction. The nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break, according to ISO 1924-2:2008, is at least 10% and at most 50% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break. Furthermore, after drying in step A3, the hydraulically entangled nonwoven fabric has a strength of at least 15 g / m³. 2 And at most 60g / m 2 The base weight.

[0080] At this point, steps A1 and A2 can be performed so that the cellulose fibers in the final hydraulically entangled nonwoven fabric tend to be more oriented in the machine direction than in the transverse direction.

[0081] In step A2, the water jets guided onto the fiber web induce entanglement of the cellulose fibers, thereby producing a structure that facilitates advantageous plastic behavior in the transverse direction. "Pressure of the water jets"—the pressure used to generate the water jets, as will be understood by those skilled in the art—is, for example, in a pressure chamber. According to the inventors' findings, it is important to achieve advantageous plastic behavior in hydraulically entangled nonwovens, i.e., a low proportion of transversely oriented fibers and a greater orientation of fibers in the machine direction and thickness direction. To produce this structure according to the invention in a hydraulically entangled nonwoven, the water jets should be arranged close to each other in the transverse direction. Due to the proximity of the water jets simultaneously impacting the fiber web, the water diffuses in the machine direction rather than the transverse direction, causing the fibers to align accordingly.

[0082] Therefore, the pressure of the water jet can be reduced compared to the pressure typically used. The distance and pressure of the water jet also depend primarily on the size of the opening from which the water jet exits, and more importantly on the speed of the fiber web, allowing those skilled in the art to consider specific implementations based on experience and to select specific values ​​through simple experiments.

[0083] In a preferred embodiment of the method according to the invention, a plurality of water jets are used in step A2 to perform hydraulic entanglement, wherein the water jets are arranged in at least one row transverse to the machine direction of the fiber web.

[0084] In a preferred embodiment of the method according to the invention, the hydraulic entanglement in step A2 is carried out by at least two rows of water jets directed onto the fiber web, wherein, particularly preferably, at least one row of water jets acts on each of the two sides of the fiber web.

[0085] In a preferred embodiment of the method according to the invention, the drying in step A3 is carried out at least in part by contact with hot air, by infrared radiation, or by microwave radiation. Drying by direct contact with a heated surface is also possible, but not preferred, because the thickness of the hydraulically entangled nonwoven fabric may be reduced as a result.

[0086] The hydraulically entangled nonwoven fabric produced according to this method should be suitable for use in sections of smoking articles. This means that it can, individually or in combination, have all the features described above regarding hydraulically entangled nonwoven fabrics and defined in the dependent claims relating to hydraulically entangled nonwoven fabrics.

[0087] In an advantageous embodiment, step A1 of providing the fiber web includes steps B1 to B3:

[0088] B1 – produces an aqueous suspension containing cellulose fibers.

[0089] B2 – Apply the suspension from step B1 to the running wire mesh.

[0090] B3 – The suspension is dehydrated by running a wire mesh to form the fiber web.

[0091] In step B1, the amount or proportion of cellulose fibers in the fiber web is selected such that, after drying in step A3, the hydroentangled nonwoven fabric contains at least 50% and at most 100% cellulose fibers relative to the mass of the hydroentangled nonwoven fabric.

[0092] In step B3, the machine direction of the fiber web is defined by the running direction of the wire mesh, and the transverse direction is defined by a direction orthogonal to the machine direction and located in the plane of the fiber web.

[0093] In step B2, the suspension is applied to the running wire mesh at a speed lower than the speed of the running wire mesh. In this respect, the speeds of the running wire mesh and the suspension should be understood as being relative to the same frame of reference, such that the different speeds result in a relative speed between the suspension and the running wire mesh, as used in this embodiment of the method.

[0094] In this embodiment of the method, the fiber web at least partially achieves the desired structure because the speed at which the suspension flows onto the running web in step B2 and the speed of the running web in step B2 are appropriately adjusted relative to each other. Specifically, according to the inventors' findings, the speed at which the suspension flows onto the running web in step B2 should be lower than the speed of the running web. Due to the speed difference, the suspension is conveyed along with the web, and shear forces are generated in the suspension, which orient the cellulose fibers in the machine direction and thus contribute to the structure of the hydraulically entangled nonwoven fabric, resulting in transverse plastic deformability according to the invention. Those skilled in the art can select the magnitude of the speed difference based on their experience and by considering exemplary embodiments or through simple experimentation. According to the inventors' experience, in many cases, a structure with desired transverse plastic deformability can be obtained if the suspension is applied to the running web in step B2 at only about 90% of the speed of the running web, for example, 88% to 93% of the speed of the running web. This value is for reference only; the appropriate value of the speed difference will depend at least in part on the remaining process parameters, and therefore in practice, those skilled in the art will determine it experimentally, wherein the guiding principle and the final criterion is the characteristic plastic deformation property of the hydraulically entangled nonwoven fabric produced in the transverse direction, as described above, which is characterized by tensile testing in the transverse direction according to reference to ISO 1924-2:2008.

[0095] In a preferred embodiment, the aqueous suspension in step B1 has a solids content of up to 3.0%, particularly preferably up to 1.0%, more particularly preferably up to 0.2%, and especially up to 0.05%. The particularly low solids content of the suspension enables the formation of a low-density fiber web in step B3, which is advantageous for the filtration efficiency of the sections manufactured from it.

[0096] In a preferred embodiment, the running wire mesh in steps B2 and B3 is tilted upward at an angle of at least 3° and at most 40° relative to the horizontal direction in the machine direction of the fiber web, particularly preferably at least 5° and at most 30°, and more particularly preferably at least 15° and at most 25°.

[0097] In a preferred embodiment, the method includes the following steps: wherein a pressure difference is applied between the two sides of a running wire mesh to support the dehydration of the suspension in step B3, wherein particularly preferably, the pressure difference is generated by a vacuum chamber or a suitably shaped foil.

[0098] In a preferred embodiment, the method includes further steps in which one or more additives are applied to the fiber web. The additives are preferably selected from alkyl ketene dimers (AKD), acid anhydrides such as alkenyl succinic anhydride (ASA), polyvinyl alcohol, waxes, fatty acids, starch, starch derivatives, carboxymethyl cellulose, alginate, chitosan, wet strength agents, or substances for adjusting pH (e.g., organic or inorganic acids or bases) and mixtures thereof. Alternatively or additionally, one or more additives may be applied, selected from citrates such as trisodium citrate or tripotassium citrate, malates, tartrates, acetates such as sodium acetate or potassium acetate, nitrates, succinates, fumarates, gluconates, glycolates, lactates, oxalates, salicylates, α-hydroxyoctanoates, phosphates, polyphosphates, chlorides, and bicarbonates and mixtures thereof.

[0099] In a preferred embodiment, one or more additives are applied between or after step A3 of the method according to the invention, followed by other steps for drying the fiber web. Attached Figure Description

[0100] Figure 1 Force-elongation diagrams of hydraulically entangled nonwoven fabrics according to the present invention are shown by way of example.

[0101] Figure 2 The force-elongation diagram of a filter material not according to the invention is shown by way of example.

[0102] Figure 3 An apparatus is shown that allows for a method according to the invention for manufacturing a hydraulically entangled nonwoven fabric.

[0103] Figure 4 Force-elongation curves measured in the transverse direction for embodiments A, B, and C according to the present invention are shown.

[0104] Figure 5 The force-elongation curves for comparative example Z (not according to the invention) measured in the transverse direction are shown. Detailed Implementation

[0105] The following describes hydraulically entangled nonwovens, methods for manufacturing hydraulically entangled nonwovens, smoking article sections, and some preferred embodiments of smoking articles. Furthermore, comparative examples not based on the invention are described.

[0106] Exemplary implementation schemes A, B, and C

[0107] Figure 3 The apparatus shown is used to manufacture according to embodiments A, B and C of the present invention.

[0108] In step B1, a suspension 31 of pulp fibers and fibers from regenerated cellulose is provided in storage tank 32. In step B2, the suspension is pumped from storage tank 32 to a running wire mesh 33 that is inclined upwards relative to the horizontal. In step B3, the suspension is dehydrated through a vacuum chamber 39, forming a fiber web 34 on the wire mesh, the general direction of movement of which is indicated by arrow 310. It should be noted that steps B1 to B3 are specific sub-steps of the general process step A1 (providing a fiber web containing cellulose fibers). At this point, to ensure that the fibers are oriented primarily in the machine direction, the speed at which the wire mesh 33 moves is selected to be approximately 10% higher than the speed of the suspension 31 flowing from storage tank 32. In step C4, the fiber web 34 is removed from the wire mesh 33 and transferred to a support wire mesh 35 that is also in operation. There, water jets 311, arranged in several rows transverse to the machine direction of the fiber web 34, are guided from device 36 onto the fiber web 34 to entangle the fibers and solidify the fiber web 34 into a nonwoven fabric, step A2. Continuing in step A2, water jets 312 are also guided to the other side of the fiber web 34 via an auxiliary device 37. Then, in step A3, the still, damp nonwoven fabric is passed through drying unit 38 and dried there to obtain a hydraulically entangled nonwoven fabric.

[0109] To create hydraulically entangled nonwovens, pulp fibers produced from coniferous wood and A mixture of fibers, wherein the amount of fibers selected is such that the final hydroentangled nonwoven fabric consists of 65% pulp fibers and 35%... Fiber composition. According to ISO 536:2019, the final hydraulically entangled nonwoven fabric has a fiber composition of 55 g / m². 2The base weight.

[0110] In step A2 of the manufacturing process, firstly, Figure 3 The water jets 311 in the three rows are guided to the first side of the fiber web 34, and then... Figure 3 A water jet 312 is guided onto the second side of the fiber web 34. To obtain different hydraulically entangled nonwovens according to inventions A, B, and C, the pressure of the water jet varies from about 2 MPa to about 40 MPa (low, medium, and high) in three steps. The diameter of the opening from which the water jet exits between the rows is different and selected from 80 μm to 120 μm; the distance from center to center of the opening is 0.3 mm.

[0111] Samples were taken from these hydraulically entangled nonwovens in the transverse direction, and force-elongation diagrams were recorded in a tensile test according to ISO 1924-2:2008. The results are shown in... Figure 4 The x-axis 40 shows the elongation percentage (%), while the y-axis 41 shows the force (N). Three lines, A, B, and C, illustrate the force-elongation diagrams for three types of hydraulically entangled nonwovens according to the present invention (A, B, and C). By way of example, for the hydraulically entangled nonwoven C, the determination of the nonlinear portion of the absorbed deformation energy up to half the breaking elongation is explained relative to the total absorbed deformation energy up to half the breaking elongation.

[0112] At half the elongation at break ε b / 2, determine the corresponding force F(ε) b / 2), and the deformation energy E lin The linear part can be calculated by the following formula.

[0113]

[0114] The total deformation energy absorbed up to half the elongation at break corresponds to the energy absorbed by the x-axis 40 and curve C from ε = 0 to ε = ε. b The region spanned by / 2 can be determined with sufficient accuracy using numerical integration without any problems. If we subtract the deformation energy E from it... lin The linear portion, then the remaining shaded region, which corresponds to the deformation energy E n1 The nonlinear part.

[0115] For all hydraulically entangled nonwovens A, B, and C, the deformation energy was measured up to half the elongation at break, and the results are shown in Table 1, where E is the total deformation energy. lin It is the linear part of the deformation energy, E nlThis is the nonlinear part of the deformation energy, each extending transversely up to half the elongation at break. The deformation energy is numerically determined from the force-elongation curve and therefore formally has the unit N%. To obtain J / m... 2 The commonly used units still need to consider the sample geometry. However, since only proportions relative to each other are important here, and since the sample geometry is identical, this is not necessary. The elongation at break ε is also shown. b The force F(ε) at half the elongation at break b / 2).

[0116] A Low 43.0 4.28 59.3 46.0 13.3 22.4 B middle 40.8 3.92 55.3 40.0 15.3 27.7 C high 32.4 3.24 34.1 26.2 7.9 23.0

[0117] Table 1

[0118] The values ​​in Table 1 indicate that, for embodiments A, B, and C according to the invention, the nonlinear portion of the deformation energy is approximately 20% to approximately 30%. It is also noteworthy that the elongation at break decreases as the water jet pressure increases. For this reason, choosing a lower water jet pressure is advantageous, as in addition to good plastic elongation properties, larger permanent deformation may also occur during coiling.

[0119] Comparative Example D

[0120] Comparative Example D relates to the manufacture of filter material in a method comprising only steps B1 to B3 and step A3, but excluding the step of using a fiber web for hydraulic entanglement. Therefore, the filter material from Comparative Example D is not according to the invention, as it is not a hydraulically entangled nonwoven fabric. Comparative Example D essentially serves to demonstrate that the execution of steps B1 to B3 (as a sub-step of a preferred embodiment of step A1) is indeed suitable for structures that contribute to resulting in a desired characteristic plastic deformability in the transverse direction, if in step B2, the suspension is applied to the running wire mesh at a reduced rate.

[0121] To manufacture the filter material, pulp fibers from coniferous wood and... A blend of fibers, wherein the amount of fibers selected results in the final filter material consisting of 80% pulp fibers and 20% [unspecified material]. Fiber composition. According to ISO 536:2019, the final filter material has a fiber content of 15 g / m³. 2 The base weight.

[0122] In step B2 of this method, the outflow rate of the suspension is selected to be 10% lower than the speed of the running wire mesh.

[0123] Four samples were taken transversely from the obtained filter material D, and force-elongation diagrams were recorded in the tensile test according to ISO 1924-2:2008. The evaluation of the force-elongation diagrams was similar to that in embodiments A, B, and C. The results of the four measurements are shown in Table 2.

[0124] D 4.20 5.97 9.19 6.27 2.92 31.8 D 3.13 5.43 5.91 4.25 1.66 28.1 D 3.56 5.79 7.39 5.15 2.24 30.3 D 4.08 5.90 8.55 6.02 2.53 29.6

[0125] Table 2

[0126] The values ​​in Table 2 indicate that the resulting filter material D has a nonlinear component of approximately 30% of the deformation energy and exhibits low variance in repeated measurements of the same sample material. This demonstrates that steps B1 through B3 of the method do indeed contribute to the desired plastic deformability in the transverse direction when the suspension in step B2 is applied to the running wire mesh at a reduced rate.

[0127] Exemplary Implementation E

[0128] On the other hand, in order to obtain the characteristic lateral plastic deformability according to the invention in hydraulically entangled nonwovens, the special execution of step A1 (with the reduced application rate of the suspension in step B2) used in embodiments A, B, and C is not required. This can be seen from embodiment E described below.

[0129] To manufacture the hydraulically entangled nonwoven fabric in exemplary embodiment E, pulp fibers from coniferous wood and A mixture of fibers, wherein the amount of fibers selected is such that the final hydroentangled nonwoven fabric consists of 80% pulp fibers and 20%... Fiber composition. Step A1 is performed without first providing the pulp fibers in the fiber web with a preferred orientation transverse to the machine direction via step B2. According to ISO 536:2019, the final hydraulically entangled nonwoven fabric has a density of 15 g / m². 2 The base weight.

[0130] Step A2 for hydraulic entanglement is performed as in step A2 of exemplary embodiment B.

[0131] Two samples were taken transversely from the hydraulically entangled nonwoven fabric E, and force-elongation diagrams were recorded in a tensile test according to ISO 1924-2:2008. The force-elongation diagrams were evaluated similarly to those in embodiments A through C. The results of the two measurements are shown in Table 3.

[0132] E 3.26 2.75 3.01 2.47 0.53 17.72 E 3.95 2.85 3.42 2.82 0.59 17.37

[0133] Table 3

[0134] The values ​​in Table 3 indicate that the hydraulically entangled nonwoven fabric E thus produced has a nonlinear deformation energy ratio of approximately 17%. A comparison with exemplary embodiments A to C, which are produced by a combination of properly performing hydraulic entanglement in step A2 and pre-structuring the fiber web by reducing the application speed in step B2, shows that this combination provides a higher ratio of nonlinear deformation energy of approximately 22% to approximately 28%, and thus can result in better performance during crimping. Of course, as in exemplary embodiment E, the combined method incurs slightly higher costs compared to the case where the characteristic lateral plastic deformability according to the invention is obtained solely through properly performing hydraulic entanglement in step A2. Exemplary embodiment E demonstrates that this is indeed possible.

[0135] Comparative Example Z

[0136] To manufacture a filter material that is not according to the invention, a mixture of the same fibers as in exemplary embodiment D is used. The basis weight remains 15 g / m³. 2 However, only the machine settings commonly used in filter paper manufacturing are employed.

[0137] Three samples were taken transversely from the filter material of Comparative Example Z, and force-elongation diagrams were recorded in tensile testing according to ISO 1924-2:2008. Similar to Embodiment A.

[0138] Z 3.21 8.38 7.22 6.71 0.52 7.17 Z 3.23 7.42 6.40 5.97 0.42 6.64 Z 3.15 7.10 5.89 5.58 0.32 5.38

[0139] Table 4

[0140] The force-elongation curve of comparative example Z is shown in Figure 5 Even without quantitative analysis, it is clear that this behavior is essentially closer to linear elastic behavior, meaning that deformation is largely reversed upon removal of the load, and much higher elongation and force are required to achieve permanent deformation. This implies that tensile strength or elongation at break can easily be exceeded in the transverse direction.

[0141] Manufacturing sections and smoking products

[0142] Each of the hydraulically entangled nonwoven fabrics in exemplary embodiments A to E and the filter material of comparative example Z are used to manufacture filter rods wrapped in paper with a length of 100 mm and a diameter of 7.85 mm. The width of the hydraulically entangled nonwoven fabric and the machine settings during filter manufacturing are selected to produce a suction resistance of 450 ± 10 mm WG.

[0143] The filter rod can be manufactured from the hydraulically entangled nonwoven fabric of exemplary embodiments A to C and E, and the filter material of comparative example Z. However, during manufacturing, it was found that for the hydraulically entangled nonwoven fabric of exemplary embodiments A to C and E, the crimping process is less sensitive to changes in machine settings, and in particular to the setting of the distance between the rollers during crimping, than in comparative example Z.

[0144] Filter cigarettes are manufactured using conventional methods according to existing technologies, specifically from exemplary embodiments A to C and E, and comparative example Z. This manufacturing method has no problems.

[0145] Therefore, it can be seen that the nonwoven fabrics made by the hydraulic entanglement according to the invention are more reliable and easier to manufacture sections and smoking articles than those made by ordinary hydraulically entangled nonwoven materials or paper, and better results can be obtained during curling due to the advantageous plastic elongation behavior.

Claims

1. A hydraulically entangled nonwoven fabric for manufacturing sections of smoking articles, wherein the hydraulically entangled nonwoven fabric is in web shape and contains at least 50% and at most 100% cellulose fibers, each relative to the mass of the hydraulically entangled nonwoven fabric. The hydroentangled nonwoven fabric described herein has a density of at least 15 g / m². 2 And at most 60 g / m 2 The basis weight, wherein the hydraulically entangled nonwoven fabric has a machine direction and a transverse direction orthogonal to the machine direction and located in the plane of the web of the hydraulically entangled nonwoven fabric, and wherein the hydraulically entangled nonwoven fabric has a characteristic plastic deformability in the transverse direction, characterized in that, In the tensile test in the said transverse direction according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 10% and at most 50% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break.

2. The hydroentangled nonwoven fabric according to claim 1, wherein the proportion of cellulose fibers in the hydroentangled nonwoven fabric is at least 60% and at most 100%, each relative to the mass of the hydroentangled nonwoven fabric.

3. The hydroentangled nonwoven fabric according to claim 2, wherein the proportion of cellulose fibers in the hydroentangled nonwoven fabric is at least 70% and at most 95%, each relative to the mass of the hydroentangled nonwoven fabric.

4. The hydroentangled nonwoven fabric according to claim 1, wherein the cellulose fibers are formed from pulp fibers or fibers derived from regenerated cellulose, or mixtures thereof.

5. The hydraulically entangled nonwoven fabric according to claim 4, wherein the pulp fibers are derived from coniferous wood or a variety of coniferous woods, deciduous wood or a variety of deciduous woods; or from a mixture of pulp fibers from various of these sources.

6. The hydraulically entangled nonwoven fabric according to claim 5, wherein the pulp fibers are derived from hemp, flax, jute, ramie, kenaf, kapok, coconut, Manila hemp, sisal, bamboo, cotton, or thatch; or from a mixture of pulp fibers from various of these sources.

7. The hydroentangled nonwoven fabric according to claim 4, wherein the proportion of fibers from regenerated cellulose is at least 5% and at most 50%, each relative to the mass of the hydroentangled nonwoven fabric.

8. The hydroentangled nonwoven fabric according to claim 7, wherein the proportion of fibers from regenerated cellulose is at least 10% and at most 45%, each relative to the mass of the hydroentangled nonwoven fabric.

9. The hydroentangled nonwoven fabric of claim 7, wherein the proportion of fibers from regenerated cellulose is at least 15% and at most 40%, each relative to the mass of the hydroentangled nonwoven fabric.

10. The hydroentangled nonwoven fabric of claim 4, wherein the fibers derived from regenerated cellulose are at least partially formed of viscose fiber, modal fiber, Lyocell® fiber, Tencel® fiber, or mixtures thereof.

11. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, having a density of at least 18 g / m². 2 And at most 55 g / m 2 The base weight.

12. The hydraulically entangled nonwoven fabric according to claim 11, having a density of at least 20 g / m³. 2 And at most 50 g / m 2 The base weight.

13. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, wherein the hydraulically entangled nonwoven fabric has a characteristic plastic deformability in the transverse direction, characterized in that, In the tensile test in the said transverse direction according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 15% and at most 40% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break.

14. The hydraulically entangled nonwoven fabric according to claim 13, wherein the hydraulically entangled nonwoven fabric has a unique plastic deformability in the transverse direction, characterized in that, In the tensile test in the said transverse direction according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 15% and at most 35% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break.

15. The hydraulically entangled nonwoven fabric according to claim 13, wherein the hydraulically entangled nonwoven fabric has a unique plastic deformability in the transverse direction, characterized in that, In the tensile test in the said transverse direction according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 18% and at most 32% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break.

16. The hydroentangled nonwoven fabric according to any one of claims 1 to 10, comprising at least one additive selected from alkyl ketene dimers; acid anhydrides; polyvinyl alcohol; waxes; fatty acids; starch; starch derivatives; carboxymethyl cellulose; alginate; chitosan; wet strength agents; or pH-adjusting substances; or mixtures of two or more of these additives.

17. The hydroentangled nonwoven fabric according to claim 16, wherein the additive is selected from alkenyl succinic anhydride; organic or inorganic acids or bases; or mixtures of two or more of these additives.

18. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, comprising at least one additive selected from citrate; malate; tartrate; acetate; nitrate; succinate; fumarate; gluconate; glycolate; lactate; oxalate; salicylate; α-hydroxyoctanoate; phosphate; polyphosphate; chloride and bicarbonate; or a mixture of two or more of these additives.

19. The hydroentangled nonwoven fabric according to claim 18, wherein the additive is selected from trisodium citrate; tripotassium citrate; sodium acetate; potassium acetate; or a mixture of two or more of these additives.

20. The hydroentangled nonwoven fabric according to any one of claims 1 to 10, comprising at least one substance selected from triacetin, propylene glycol, sorbitol, glycerol, polyethylene glycol, polypropylene glycol, polyvinyl alcohol and triethyl citrate, or a mixture of two or more of these substances.

21. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, wherein at least a portion of the cellulose fibers is loaded with filler.

22. The hydraulically entangled nonwoven fabric according to claim 21, wherein the filler is formed of mineral particles.

23. The hydraulically entangled nonwoven fabric according to claim 21, wherein the filler is formed of calcium carbonate particles.

24. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, wherein the thickness of one layer of the hydraulically entangled nonwoven fabric, as measured according to ISO 534:2011, is at least 25 μm and at most 1000 μm.

25. The hydraulically entangled nonwoven fabric of claim 24, wherein the thickness of one layer of the hydraulically entangled nonwoven fabric, as measured according to ISO 534:2011, is at least 30 μm and at most 800 μm.

26. The hydraulically entangled nonwoven fabric of claim 24, wherein the thickness of one layer of the hydraulically entangled nonwoven fabric, as measured according to ISO 534:2011, is at least 35 μm and at most 600 μm.

27. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, wherein the tensile strength of the hydraulically entangled nonwoven fabric relative to the width in the transverse direction, as measured according to ISO 1924-2:2008, is at least 0.05 kN / m and at most 5 kN / m.

28. The hydraulically entangled nonwoven fabric according to claim 27, wherein the tensile strength of the hydraulically entangled nonwoven fabric relative to the width in the transverse direction, as measured according to ISO 1924-2:2008, is at least 0.07 kN / m and at most 4 kN / m.

29. The hydraulically entangled nonwoven fabric according to any one of claims 1 to 10, wherein the elongation at break of the hydraulically entangled nonwoven fabric in the transverse direction, as measured according to ISO 1924-2:2008, is at least 0.5% and at most 50%.

30. The hydraulically entangled nonwoven fabric of claim 29, wherein the elongation at break of the hydraulically entangled nonwoven fabric in the transverse direction, as measured according to ISO 1924-2:2008, is at least 0.8% and at most 40%.

31. A segment for a smoking article comprising a hydraulically entangled nonwoven fabric of any one of claims 1 to 30, and a packaging material, which are laterally aggregated.

32. The segment of claim 31, wherein the segment is cylindrical with a diameter of at least 3 mm and at most 10 mm, and / or wherein the length of the segment is at least 4 mm and at most 40 mm.

33. The segment of claim 32, wherein the diameter of the segment is at least 4 mm and at most 9 mm, and / or the length of the segment is at least 6 mm and at most 35 mm.

34. The segment of claim 32, wherein the diameter of the segment is at least 5 mm and at most 8 mm, and / or the length of the segment is at least 10 mm and at most 28 mm.

35. The segment of claim 31, wherein the suction resistance per unit length of the segment according to ISO 6565:2015 is at least 1 mmWG / mm and at most 12 mmWG / mm.

36. The segment of claim 35, wherein the suction resistance per unit length of the segment according to ISO 6565:2015 is at least 2 mmWG / mm and at most 10 mmWG / mm.

37. The section according to any one of claims 31 to 36, wherein the packaging material is formed of paper or film.

38. The segment according to any one of claims 31 to 36, wherein the packaging material has a content of at least 20 g / m³ according to ISO 536:2019. 2 And at most 150 g / m 2 The base weight.

39. The segment of claim 38, wherein the packaging material has a content of at least 30 g / m³ according to ISO 536:2019. 2 And at most 130 g / m 2 The base weight.

40. A method for manufacturing a segment according to any one of claims 31 to 39, wherein, The hydraulically entangled nonwoven fabric according to any one of claims 1 to 30 is curled or pleated to form a continuous bundle of filaments produced by the curled or pleated hydraulically entangled nonwoven fabric, the bundle of filaments of the curled or pleated hydraulically entangled nonwoven fabric is encapsulated by packaging material, and the encapsulated bundle of filaments is cut into individual rods having a defined length.

41. A smoking article comprising a segment containing an aerosol-forming material and a segment according to any one of claims 31 to 39, wherein the segment according to any one of claims 31 to 39 is the segment of the smoking article located closest to the mouth end.

42. The smoking article of claim 41, wherein the smoking article is a filter cigarette and the aerosol forming material is tobacco or contains tobacco.

43. The smoking article of claim 41, wherein the smoking article is a smoking article in which the aerosol forming material is heated but not burned during its intended use, wherein the aerosol forming material comprises a material selected from tobacco, reconstituted tobacco, nicotine, glycerin, propylene glycol, or mixtures thereof.

44. The smoking article of claim 43, wherein the aerosol-forming material is present in liquid form and is located in a corresponding container in the smoking article.

45. A method for manufacturing a hydraulically entangled nonwoven fabric according to any one of claims 1 to 30, wherein the method comprises the following steps: A1 – Provides a fiber web comprising cellulose fibers having a machine orientation and a transverse orientation orthogonal to the machine orientation and located in the plane of the fiber web. A2 – A hydraulically entangled fiber web produced by causing the fiber web to become hydraulically entangled through a water jet directed onto it. A3 – Dry the hydraulically entangled fiber web. In step A1, the proportion of cellulose fibers in the fiber web is selected such that, after drying in step A3, the hydroentangled nonwoven fabric contains at least 50% and at most 100% cellulose fibers relative to the mass of the hydroentangled nonwoven fabric. Steps A1 and A2 are performed such that the hydraulically entangled nonwoven fabric, which provides characteristic plastic deformability in the transverse direction, is characterized in that, in a tensile test in the transverse direction of the hydraulically entangled nonwoven fabric after drying in step A3 according to ISO 1924-2:2008, the nonlinear portion of the deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break is at least 10% and at most 50% of the total deformation energy absorbed by the hydraulically entangled nonwoven fabric up to half the elongation at break. Furthermore, after drying in step A3, the hydraulically entangled nonwoven fabric has a density of at least 15 g / m³. 2 And at most 60 g / m 2 The base weight.

46. ​​The method of claim 45, wherein a plurality of water jets are used in step A2 to perform the hydraulic entanglement, wherein the water jets are arranged in at least one row transverse to the machine direction of the fiber web.

47. The method of claim 46, wherein the hydraulic entanglement in step A2 is achieved by at least two rows of water jets directed onto the fiber web, wherein at least one row of water jets acts on each of the two sides of the fiber web.

48. The method of claim 45, wherein the drying in step A3 is performed at least in part by contact with hot air, by infrared radiation, or by microwave radiation.

49. The method of claim 45, wherein step A1 for providing the fiber web comprises the following sub-steps B1 to B3: B1 – produces an aqueous suspension containing cellulose fibers. B2 – Apply the suspension from step B1 to the running wire mesh. B3 – The suspension is dehydrated by the running wire mesh to form the fiber web. In step B1, the amount or proportion of cellulose fibers is selected such that, after drying in step A3, the hydraulically entangled nonwoven fabric contains at least 50% and at most 100% cellulose fibers relative to the mass of the hydraulically entangled nonwoven fabric. In step B3, the machine direction of the fiber web is defined by the running direction of the wire mesh, and the transverse direction is defined by a direction orthogonal to the machine direction and located in the plane of the fiber web. In step B2, the suspension is applied to the running wire mesh at a speed lower than the speed of the running wire mesh.

50. The method of claim 49, wherein the aqueous suspension in step B1 has a solids content of up to 3.0%.

51. The method of claim 49, wherein the aqueous suspension in step B1 has a solids content of up to 1.0%.

52. The method of claim 49, wherein the aqueous suspension in step B1 has a solids content of up to 0.2%.

53. The method of claim 49, wherein the aqueous suspension in step B1 has a solids content of up to 0.05%.

54. The method of claim 49, wherein the operating wire mesh in steps B2 and B3 is inclined upward at an angle of at least 3° and at most 40° relative to the horizontal direction in the machine direction of the fiber web.

55. The method of claim 49, wherein the operating wire mesh in steps B2 and B3 is inclined upward at an angle of at least 5° and at most 30° relative to the horizontal direction in the machine direction of the fiber web.

56. The method of claim 49, wherein the operating wire mesh of steps B2 and B3 is inclined upward at an angle of at least 15° and at most 25° relative to the horizontal direction in the machine direction of the fiber web.

57. The method according to any one of claims 49 to 56, further comprising the step of generating a pressure difference between the two sides of the running wire mesh to support the dehydration of the suspension in step B3, wherein the pressure difference is generated by a vacuum chamber or a suitably shaped foil.

58. The method according to any one of claims 45 to 56, further comprising the step of applying one or more additives to the fiber web, wherein the one or more additives are selected from alkyl ketene dimers; acid anhydrides; polyvinyl alcohol; waxes; fatty acids; starch; starch derivatives; carboxymethyl cellulose; alginate; chitosan; wet strength agents; or pH-adjusting substances; and mixtures thereof.

59. The method of claim 58, wherein the one or more additives are selected from alkenyl succinic anhydride; organic or inorganic acids or bases; and mixtures thereof.

60. The method according to any one of claims 45 to 56, further comprising the step of applying one or more additives to the fiber web, wherein the one or more additives are selected from citrate; malate; tartrate; acetate; nitrate; succinate; fumarate; gluconate; glycolate; lactate; oxalate; salicylate; α-hydroxyoctanoate; phosphate; polyphosphate; chloride and bicarbonate; and mixtures thereof.

61. The method of claim 60, wherein the one or more additives are selected from trisodium citrate; tripotassium citrate; sodium acetate; potassium acetate; and mixtures thereof.

62. The method of claim 58, wherein the one or more additives are applied between step A2 and step A3, or after step A3, followed by other steps of drying the fiber web.

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