A BALE of nonwoven material, a method for manufacturing a BALE of nonwoven material, and a method for manufacturing a filter

Abstract

The present invention relates to a bale (400), a method for folding a bale and a filter for use in an aerosol generating article, the bale being formed by folding a continuous sheet of nonwoven material. The bale comprising a continuous sheet of nonwoven material folded into a plurality of layers stacked onto each other in a first direction (V), wherein folding edges (440) of the individual layers of the plurality of layers are located on a first side of the bale and on a second side of the bale opposite to the first side. On at least one of the first and second sides, a first layer (431) of the plurality of layers is positioned on a second layer (432) of the plurality of layers such that a folding edge of the first layer is positioned at a first distance (a) to a folding edge of the second layer in a second direction (H1) substantially perpendicular to the first direction.

Description

[0001] A BALE OF NONWOVEN MATERIAL, A METHOD FOR MANUFACTURING A BALE OF NONWOVEN MATERIAL, AND A METHOD FOR MANUFACTURING A FILTER

[0002] TECHNICAL FIELD

[0003] The present invention relates to a bale, a method for folding a bale and a filter for use in an aerosol generating article, the bale being formed by folding a continuous sheet of nonwoven material.

[0004] BACKGROUND

[0005] Smoking articles, such as cigarettes have cellulose acetate filters to filter components from the aerosols inhaled by a consumer. However, when the used article is improperly thrown, it often ends up in the environment. Therefore, to decrease the environmental impact, the filters comprising natural materials is becoming a more and more sought- after aim for manufacturers.

[0006] For example, in GB 2525363 A, a biodegradable cigarette filter tow is disclosed that includes a mixture of at least two or more natural materials selected from the group consisting of hemp fibre, flax fibre, abaca fibre or pulp, sisal fiber or pulp, wood pulp or cotton fibre or cotton flock, and a natural binder.

[0007] WO 2022 / 053621 relates to a filter comprising a nonwoven substrate having a low density and comprising natural fibers and a binder, wherein the filter can be used as a filter for a smoking or vaping article.

[0008] The nonwoven base material for production of these filters is typically stored on a set of bobbins that provide the nonwoven material to a production facility. A first bobbin is configured to provide the nonwoven material to the production facility, and a second bobbin functions as a backup in case the nonwoven material on the first bobbin is used. To avoid downtime in the production, a buffer zone is implemented to provide material when a bobbin is changed, so that when the nonwoven material of the second bobbin is supplied to the buffer zone while replacing the first (empty) bobbin with a new bobbin. While this arrangement allows to provide material in a continuous manner, the space occupied by the bobbins and the buffer zone is relatively large. As already disclosed in a co-pending application in the name of the same Applicant, one alternative is to store and provide the nonwoven in the form of a bale of stacked nonwoven material. Typically, a continuous sheet of nonwoven material is stacked on a bale, and an end of the continuous sheet is fed into the production machine. Since replacing the bale is faster than changing a bobbin and also taking into account that the end of the nonwoven material on a bale can be easily connected to the new nonwoven material on a new bale to provide continuity of the material supplied to the production machine, the downtime and the space requirement in the facility is reduced. However, folding edges at the sides of the bale can have a negative impact on the filter manufacturing / filter properties. For example, the weight of higher layers of nonwoven material on the bale may exert high pressures on the folding edges of lower layers of nonwoven material on the bale. This may lead to tearing of the sheet of nonwoven material during the manufacturing of the filter.

[0009] It is thus desired to provide a bale of nonwoven material, and to manufacture a filter from the nonwoven material, such that the above mentioned possible negative impact on the filter manufacturing and the filter properties can be avoided or at least reduced. It is also desired to provide a method for obtaining the bale and to manufacture the filter while eliminating or at least reducing the above-mentioned drawbacks related to the folding edges of the stacked layers of nonwoven material.

[0010] It has to be also noted that the prior art discloses filters comprising natural nonwoven material, due to the low density of the filter, the nonwoven substrate may break during filter manufacturing, especially in / after the crimping process which is normally used for filter production for sheet substrate and the filter has a risk of falling apart, which can cause an unpleasant smoking experience for a user. Moreover, during production of nonwoven substrates, the binder tends to leak out of the nonwoven substrate, contaminating the manufacturing machines, which reduces the yield of the filter production.

[0011] It is thus desired to provide a filter which can be manufactured with reduced risk of breaking during production and with a reduced risk of falling apart during use and a reduced risk of binder leakage during production of the non-woven substrate, in particular when the nonwoven material to be used for the filter production is arranged on a bale. It is desired to provide a method for manufacturing the filter. SUMMARY OF THE INVENTION

[0012] The present invention provides a bale of nonwoven substrate, as well as a filter manufactured by nonwoven material stored on said bale and a method for manufacturing a filter comprising nonwoven material stored on said bale, that solves some or all of the above problems.

[0013] The present invention also provides a filter with a nonwoven substrate comprising natural fibers and a binder. Preferably the nonwoven material is obtained from the bale according to any one of the 22ndto 28thembodiment. A 1stembodiment of the invention is directed to a filter for use in a smoking or aerosol generating article, the filter comprising a nonwoven substrate comprising natural fibers and a binder, wherein the natural fibers represent from 85 to 95%, preferably 86.9 to 95% by weight of the nonwoven substrate, and the binder represents from 5 to 15% , preferably 5 to 13.1% by weight of the nonwoven substrate, wherein the nonwoven substrate has a dry tensile strength of at least 10 N / 5 cm, preferably at least 12 N / 5 cm and most preferably at least 14 N / 5 cm, and the nonwoven substrate has a thickness of from 0.4 to 1.0 mm, preferably 0.5 to 0.9 mm, and most preferably from 0.5 to 0.7 mm. Preferably, the natural fiber represents more than 85 to 90% by weight of the nonwoven substrate and the binder represents from 5 to less than 15 % by weight of the nonwoven substrate, preferably the nonwoven material is obtained from the bale according to any one of the 22ndto 28thembodiment. Preferably the nonwoven material herein disclosed and / or claimed, see for example any of the 1st to 18th embodiment, can be arranged in a bale herein disclosed and / or claimed, see for example any one of the 22ndto 28thembodiment.

[0014] Filters manufactured from nonwoven substrates with a tensile strength below 10 N / 5 cm have an increased risk of breaking of the substrate during manufacturing or in falling apart due to the low tensile strength. The above composition results in a filter made of natural material that is durable and has flow properties and TN CO emissions similar to filters known in the art. Moreover, the leaking of the binder from the nonwoven substrate during manufacturing is reduced.

[0015] According to a 2nd embodiment, in the preceding embodiment, the natural fibers represent from 90 to 93% by weight of the nonwoven substrate, and / or the binder represents 7 to 10% by weight of the nonwoven substrate. Preferably, the natural fibers represent from 91 to 95% by weight of the nonwoven substrate, and / or the binder represents 5 to 9% by weight. More preferably, the natural fibers represent from 93 to 95% by weight of the nonwoven substrate, and / or the binder represents from 5 to 7% by weight.

[0016] Furthermore, in any of the preceding embodiments, the natural fibers represent at least 86% by weight of the nonwoven substrate, preferably at least 87% by weight of the nonwoven substrate, more preferably at least 88% by weight of the nonwoven substrate, and most preferably at least 89% by weight of the nonwoven substrate, and / or at most 95% by weight of the nonwoven substrate, preferably at most 94% by weight of the nonwoven substrate, and most preferably at most 93% by weight of the nonwoven substrate, and / or the binder represents at most 14% by weight of the nonwoven substrate, preferably at most 13% by weight of the nonwoven substrate, more preferably at most 12% by weight of the nonwoven substrate, and most preferably at most 11% by weight of the nonwoven substrate, and / or at least 5% by weight of the nonwoven substrate, preferably at least 6% by weight of the nonwoven substrate, and most preferably at least 7% by weight of the nonwoven substrate.

[0017] According to a 3rd embodiment, in any one of the preceding embodiments, the nonwoven substrate has a volume density of at least 50 mg / cm3, preferably of at least 55 mg / cm3and most preferably above 60 mg / cm3, or at least 62 mg / cm3and / or a volume density of at most 140 mg / cm3, preferably at most 130 mg / cm3, even preferably at most 120 mg / cm3, of at most preferably 110 mg / cm3, or at most too mg / cm3or at most 90 mg / cm3.

[0018] According to a 4th embodiment, in any one of the preceding embodiments, the nonwoven substrate has an areal density of from 40 to 65 g / m2, preferably 45 to 60 g / m2and most preferably from 46 to 58 g / m2.

[0019] With the above embodiments, the risk of leakage from the binder can be further reduced.

[0020] According to a 5th embodiment, in any one of the preceding embodiments, the average length of the natural fibers is at most 3.5 mm, preferably at most 3.0 mm and most preferably at most 2.8 mm, and / or the average length of the natural fibers is at least 2.0 mm, preferably at least 2.3 mm and most preferably at least 2.5 mm. According to a 6th embodiment, in any one of the preceding embodiments, the natural fibers comprise or preferably consist of wood pulp, the wood pulp preferably being obtained by a kraft process.

[0021] According to a 7th embodiment, in the preceding embodiment, the wood pulp comprises a soft wood pulp and / or a hard wood pulp, preferably a Southern bleached softwood kraft, SBSK, and / or a Northern bleached softwood kraft, NBSK, wherein preferably the wood pulp comprises at least 75% SBSK, preferably at least 85% SBSK, more preferably at least 95% SBSK and most preferably 100% SBSK and / or preferably 25% NBSK or less, more preferably 5% NBSK or less.

[0022] Having natural fibers in the filter substrate reduces the environmental impact of the filters or butts improperly thrown. Moreover, nonwoven substrates made from wood pulp provide filter capabilities (pressure drop and TN CO emission) similar to filters known in the art. Consequently, the environmental impact of the filters can be reduced while similar filter capabilities are maintained. Moreover, the higher percentage of SBSK tends to reduce the pressure drop of the filter compared to higher percentage of NBSK. So, the ratio of SBSK to NBSK may be used to adjust the pressure drop of the filter.

[0023] According to an 8th embodiment, in any one of the preceding embodiments, the binder comprises at least one binding agent being a water-based polymer emulsion.

[0024] According to a 9th embodiment, in any one of the preceding embodiments, the binder comprises one or more of an aqueous copolymer dispersion of Ethylene Vinyl Acetate, EVA, and a Polyvinyl Acetate, PVAc.

[0025] According to a 10th embodiment, in the preceding embodiment, the binder comprises a combination of EVA and PVAc, wherein the ratio of EVA to PVAc is preferably between 70:30 and 30:70, more preferably between 60:40 and 40:60, even more preferably between 55:45 and 45:55 and most preferably 50:50.

[0026] According to an 11th embodiment, in the 9th or 10th embodiment, the PVAc is a Polyvinyl alcohol stabilized polyvinyl acetate, preferably stabilized by a vinyl alcohol polymer, PVOH, a dextrin, or combinations thereof, wherein the EVA is stabilized with one or more of the following: a surfactant, an emulsifier, a cellulose derivate, PVOH, a colloid, and combinations thereof. According to a 12th embodiment, in any one of the preceding embodiments, the nonwoven substrate comprises flavor additives.

[0027] Adding flavor additives to the filter may improve the consumer experience. In particular, the flavor additives can change the taste of aerosol or smoke.

[0028] According to a 13th embodiment, in any one of the preceding embodiments, a reel width of the non-woven substrate is between 50 and 240 mm, preferably 100 and 220 mm, for example between 120 and 180 mm.

[0029] The reel width may depend on the circumference of the filter. The smaller the circumference, the narrower the width is. More particularly, when the circumference of the filter is about 16.8 mm (“super slim” format), the reel width is preferably between 50 and 100 mm. When the circumference of the filter is about 21.5 mm (“Slim format”), the reel width is preferably between 100 and 160mm. When the circumference of the filter is about 24.2 mm (“King size format”), the reel width is preferably between 120 and 180 mm.

[0030] According to a 14th embodiment, in any one of the preceding embodiments, the nonwoven substrate is crimped in the machine direction with a crimping depth of 0.2 to 1.2 mm, preferably 0.2 to 1.0 mm, more preferably of 0.5 to 1.0 or 0.5 to 0.9 mm.

[0031] A crimping depth in the above range reduces the risk of unwanted cracks in the nonwoven substrate, while the desired crimping effect is obtained.

[0032] According to a 15th embodiment, in any one of the preceding embodiments, the filter has a density between 100 and 220 mg / cm3or between 100 and 200 mg / cm3, for example of 140 mg / cm3, and / or the pressure drop at the filter is between 1.3 and 5.0 mmWC / mm or between 1.3 and 4.5 mmWC / mm, preferably between 1.8 and 3 mmWC / mm, preferably determined according to the conditions described in ISO 6565:2015.

[0033] According to a 16th embodiment, in any one of the preceding embodiments, the hardness of the filter corresponds to a decrease in the diameter of the filter in the range of 2.5 mm to 1.3 mm, more preferably in the range of 2.3 mm to 1.5 mm, preferably when being subjected to a pressure of 350g for 5s in a SODIM-H hardness measurement module. A pressure drop in the above range is similar to the pressure drop of cellulose acetate filters. Accordingly, a consumer using a smoking article / aerosol generating device with the described filter has the sought-after consumption experience.

[0034] According to a 17th embodiment, in any one of the preceding embodiments, the nonwoven substrate is brought in a rod-shaped form and is wrapped by a wrapping paper having a basis weight of from 24 to 120 gsm, or 25 to 50 gsm, preferably from 27 to 45 gsm and / or a thickness of from 0.03 to 0,13 mm or from 0.03 to 0.06 mm, preferably from 0.043 to 0.125 mm.

[0035] For example, the circumference may be between 16 to 28 mm, for example 16.8 mm, or about 16 to 26 mm, for example 21.5 mm, or about 16.8 to 24.20 mm.

[0036] According to an 18th embodiment, in the preceding embodiment, a circumference of the filter is between 16 to 28 or 20 and 28 mm, preferably between 22 and 26 mm, even more preferably between 24 and 25 mm, and most preferably 24.2 mm.

[0037] The above ranges are commonly used in state-of-the-art smoking articles / aerosol generating devices. Accordingly, a filter in the above ranges can be used in a variety of applications.

[0038] The present invention also provides an aerosol generating article, preferably a cigarette or heat-not-burn aerosol generating article.

[0039] A 19th embodiment is directed to an aerosol generating article, preferably a cigarette or heat-not-burn aerosol generating article, comprising a filter according to any one of the preceding embodiments.

[0040] According to a 20thembodiment, a tipping paper is arranged to attach the filter and the aerosol generating segment wherein the tipping paper has a basis weight of at least 30 gsm and / or a thickness of at least 35 pm. Preferably, the tipping paper has a basis weight of 55 gsm or less and a thickness of 55 pm or less. In a most preferred example, the tipping paper has a basis weight of about 50 (+ / -2) gsm and a thickness of 50 (+ / - 2) pm.

[0041] The present invention also provides a method for manufacturing of a filter comprising a nonwoven substrate.

[0042] A 21st embodiment is directed to a method for manufacturing of a filter comprising a nonwoven substrate, preferably a filter according to any one of the first to 18th embodiment, for use in a smoking or aerosol generating article, the method comprising the steps of providing a nonwoven substrate arranged as a continuous sheet (also referred to herein as “festoon”) on a bale or pallet, inserting the nonwoven substrate into a production facility for production of the filter, and crimping the nonwoven substrate into the filter, preferably the bale is a bale according to any one of the 22ndto 28thembodiment.

[0043] As mentioned above, the present invention provides a bale of nonwoven.

[0044] A 22ndfirst embodiment of the invention relates to a bale of nonwoven material. The bale comprising a continuous sheet of nonwoven material folded into a plurality of layers stacked onto each other in a first direction, wherein folding edges of the individual layers of the plurality of layers are located on a first side of the bale and on a second side of the bale opposite to the first side, wherein on at least one of the first and second side, a first layer of the plurality of layers is positioned on a second layer of the plurality of layers such that a folding edge of the first layer is positioned at a distance to a folding edge of the second layer in a second direction substantially perpendicular to the first direction.

[0045] By arranging the folding edges of individual layers of the nonwoven material on the bale at a first distance in the horizontal direction, pressure from the upper layers of nonwoven material is not directly applied to the folding edges of subsequent layers. With this configuration, in possible embodiments, the pressure on the folding edges of lower layers of nonwoven material in the bale was reduced by 66%. Hence, the overall pressure on individual folding edges is reduced and the disadvantages in the filter production due to the use of the nonwoven material are reduced.

[0046] Preferably the nonwoven material herein disclosed and / or claimed, see for example any of the 1st to 18th embodiment, can be arranged in a bale according to the invention. Advantageously by arranging the folding edges of individual layers of the nonwoven material having the features of any of the 1st to 18th embodiment on the bale at a first distance in the horizontal direction resulted in non-woven material supplied to the production machine (e.g. comprising a crimping unit) having no, or at least reduced, folding lines.

[0047] According to a 23rdembodiment in the preceding embodiment, a third layer of the plurality of layers is positioned on the second layer, such that a folding edge of the third layer is positioned at a second distance to the folding edge of the second layer in the second direction. Preferably the second distance is substantially similar to the first distance.

[0048] According to a 24thembodiment in the preceding embodiment, a fourth layer of the plurality of layers is positioned on the third layer, such that a folding edge of the fourth layer is positioned at a third distance to the folding edge of the third layer in the second direction. Preferably, the folding edge of the fourth layer is positioned substantially above the folding edge of the second layer in the first direction V. Preferably, the third distance is substantially similar to the first distance.

[0049] According to a 25thembodiment in the preceding embodiment, a fifth layer of the plurality of layers is positioned on the fourth layer, such that a folding edge of the fifth layer is positioned at a fourth distance to the folding edge of the fourth layer in the second direction. Preferably, the folding edge of the fifth layer is positioned substantially above the folding edge of the first layer in the first direction V, and / or the fourth distance is preferably substantially similar to the first distance.

[0050] According to a 26thembodiment in any one of the preceding embodiments, an nthlayer of the plurality of layers is positioned on the n-ithlayer, such that a folding edge of the nthlayer is positioned at an mthdistance to the folding edge of the n-ithlayer in the second direction, wherein n is an integer of at least 7. Preferably, the folding edge of the nthlayer is positioned substantially above the folding edge of the n-2thlayer, above the folding edge of the n-3thlayer, above the folding edge of the n-4thlayer or above the folding edge of the n-5thlayer in the first direction V, and / or the mthdistance is preferably substantially similar to the first distance.

[0051] According to a 27thembodiment in any one of the 22ndto 26thembodiments, the edges of the plurality of layers are arranged in a predetermined pattern, preferably a pattern having a zigzag-shape on at least one side of the bale, wherein the zigzag-shape is formed by at least two individual layers of the plurality of layers, preferably by at least three individual layers (431, 432, 433) of the plurality of layers (431, 432, 433, 434, 435)? more preferably by five individual layers of the plurality of layers.

[0052] The zigzag-shape has proven to be surprisingly effective in reducing the overall pressure on the folding edges of lower layers of nonwoven material in the bale. In particular, the zigzag-shape has proven to be surprisingly effective in reducing the overall pressure on the folding edges of lower layers in the bale of the nonwoven material having the features of any of the 1st to 18th embodiment. According to a 28thembodiment in any one of the 22ndto 27thembodiments, the distance a is at least 7 mm, preferably at least 8 mm, more preferably at least 10 mm, even more preferably at least 12 mm, and most preferably at least 15 mm; and / or wherein the distance a is at most 30 mm, preferably at most 27 mm, more preferably at most 25 mm, even more preferably at most 22 mm, and most preferably at most 20 mm.

[0053] With the above values, the pressure in the folding edges of lower layers is reduced, while the stability of the bale is not impacted. Significantly higher distances may have a negative impact on the stability of the bale, while significantly lower distances reduce the positive effect on the folding edges.

[0054] According to a 29thembodiment in any one of the 22ndto 27thembodiment, the individual layers of the one or more layers are formed by two sheet portions of the continuous sheet of nonwoven. The sheet portions are formed by folding the continuous sheet of nonwoven material at the folding edge, the two sheet portions being connected to each other via the folding edge.

[0055] A 30thembodiment is directed to a method for providing a bale of nonwoven material comprising the steps of folding a continuous sheet of nonwoven material into a plurality of layers stacked onto each other in a first direction on a surface, preferably on a pallet, such that folding edges of the individual layers of the plurality of layers are located on a first side of the bale and on a second side of the bale opposite to the first side, wherein folding the continuous sheet of nonwoven material further comprises folding at least a first layer and a second layer, wherein on at least one of the first and second side of the bale, the first layer is positioned on the second layer such that a folding edge of the first layer is positioned at a first distance of a folding edge of the second layer in a second direction substantially perpendicular to the first direction.

[0056] According to a 31thembodiment in the preceding embodiment, wherein folding the continuous sheet of nonwoven material further comprises folding a third layer, wherein the third layer is positioned on the second layer, such that a folding edge of the third layer is positioned at a distance b to the folding edge of the second layer in the second direction, wherein preferably the second distance is substantially similar to the first distance.

[0057] According to a 32ndembodiment in the preceding embodiment, wherein folding the continuous sheet of nonwoven material further comprises folding a fourth layer, wherein the fourth layer is positioned on the third layer, such that a folding edge of the fourth layer is positioned at a third distance of the folding edge of the third layer in the second direction, and the folding edge of the fourth layer is preferably positioned substantially above the folding edge of the second layer in the first direction , and / or the third distance is preferably substantially similar to the first distance.

[0058] According to an 33rdembodiment in the preceding embodiment, folding the continuous sheet of nonwoven material further comprises folding a fifth layer, wherein the fifth layer is positioned on the fourth layer, such that a folding edge of the fifth layer is positioned at a fourth distance to the folding edge of the fourth layer in the second direction, and the folding edge of the fifth layer is preferably positioned substantially above the folding edge of the first layer in the first direction , and / or the fourth distance is preferably substantially similar to the first distance.

[0059] According to a 34thembodiment in any one of the 29thto 32thembodiment, folding the continuous sheet of nonwoven material further comprises folding an nthlayer, wherein the nthlayer of the plurality of layers is positioned on the n-ithlayer, such that a folding edge of the nthlayer is positioned at an mthdistance to the folding edge of the n-ithlayer in the second direction, wherein n is an integer of at least 7, and the folding edge of the nthlayer is preferably positioned substantially above the folding edge of the n-2thlayer, above the folding edge of the n-3thlayer, above the folding edge of the n-4thlayer or above the folding edge of the n-5thlayer in the first direction, and / or the mthdistance is preferably substantially similar to the first distance.

[0060] According to a 35thembodiment in any one of the 30thto 34thembodiment, folding the continuous sheet of nonwoven material further comprises arranging the edges of the plurality of layers in a zigzag-shape on at least one side of the bale, wherein the zigzagshape is formed by at least two individual layers of the plurality of layers, preferably by five individual layers of the plurality of layers.

[0061] According to a 36thembodiment in any one of the 30thto 35thembodiment, the first distance is at least 7 mm, preferably at least 8 mm, more preferably at least 10 mm, even more preferably at least 12mm, and most preferably at least 15mm; and / or wherein the first distance is at most 30 mm, preferably at most 27 mm, more preferably at most 25mm, even more preferably at most 22mm, and most preferably at most

[0062] 20mm. According to a 37thembodiment in any one of the 30thto 36thembodiment, the individual layers of the one or more layers are formed by two sheet portions of the continuous sheet of nonwoven. The sheet portions are formed by folding the continuous sheet of nonwoven material at the folding edge, the two sheet portions being connected to each other via the folding edge.

[0063] A 38thembodiment is directed to a filter manufactured by crimping nonwoven material stored on a bale according to any one of the 22ndto 29thembodiment.

[0064] A 39thembodiment is directed to a method for manufacturing a filter comprising nonwoven material comprising the steps of providing a nonwoven material on a bale according to any one of the 22ndto 29thembodiment, and crimping the nonwoven material to obtain the filter.

[0065] A 40thembodiment is directed to a bale obtained according to any one of the 27thto 36thembodiment.

[0066] A 41stembodiment is directed to a filter obtained by crimping a nonwoven material obtained according to any one of the 30thto 37thembodiment.

[0067] Preferred embodiments are now described, by way of example only, with reference to the accompanying drawings.

[0068] BRIEF DESCRIPTION OF THE DRAWING

[0069] Figure 1: is a plot showing the tensile strength measurements results of exemplary nonwoven substrates at various thicknesses and binder contents;

[0070] Figure 2: is another plot showing the tensile strength measurements results of exemplary nonwoven substrates at various thicknesses and binder contents;

[0071] Figure 3: is a plot of the firmness against the pressure drop of exemplary filters comprising nonwoven substrates;

[0072] Figure 4a: shows an arrangement of nonwoven material according to a first embodiment;

[0073] Figure 4b: shows an arrangement of nonwoven material according to a second embodiment; Figure 5: shows the space requirement of a nonwoven substrate stored on a bale / pallet by means of festooning process with the space requirement of a nonwoven substrate supplied by bobbins, i.e. by a known rolling process;

[0074] Figure 6: shows a schematic view of a bale according to an embodiment of the invention;

[0075] Figure 7: shows a schematic view of a bale according to an embodiment of the invention;

[0076] Figure 8: shows a combustible aerosol-generating article according to an embodiment;

[0077] Figure 9: shows an aerosol-generating article according to an embodiment;

[0078] Figure 10: shows a non-combustible aerosol generating article according to an embodiment.

[0079] DETAILED DSCRIPTION OF THE PREFERRED EMBODIMENTS

[0080] Preferred embodiments of the present invention are described hereinafter with reference to the drawing.

[0081] In the following, a filter comprising a nonwoven substrate for use in a smoking or aerosol generating article is described in more detail.

[0082] Nonwoven substrates relate to substrates made from fiber material where the fibers are randomly arranged and bonded together thermally (e.g., melt-blown), mechanically (e.g., hydroentangled) or by means of a binder.

[0083] A filter according to an embodiment comprises a nonwoven substrate comprising natural fibers and a binder. Preferably, the nonwoven substrate is provided as a sheet. In the nonwoven substrate, the natural fibers represent 85% to 95% by weight of the nonwoven substrate and the binder represents 5 to 15% by weight of the nonwoven substrate. Preferably, the natural fiber represents more than 85% to 90% by weight of the nonwoven substrate and the binder represents from 5 to less than 15 % by weight of the nonwoven substrate. To avoid that the nonwoven substrate breaks during filter production and / or the filter comprising the nonwoven substrate falls apart, a nonwoven substrate is used with a dry tensile strength of at least io N / 5 cm, preferably at least 12 N / 5 cm and most preferably at least 14 N / 5 cm, and / or a thickness of 0.4 to 1.0 mm, preferably 0.5 to 0.9 mm, and most preferably 0.5 to 0.7 mm. Filters comprising such a nonwoven substrate have proven to be particularly resistant against breakage and were produced with a high yield. The thickness of the nonwoven substrate is measured by using a thickness gauge apparatus applying a pressure of 0.5 kPa on the specimen with a pressing surface area of 25 cm2according to EN ISO 9073-2:1996 “Test methods for nonwovens”.

[0084] In some embodiments, the natural fibers represent 90 to 93% by weight of the nonwoven substrate, and / or the binder represents 7 to 10% by weight of the nonwoven substrate. More preferably, natural fibers represent between more than 90 % and 93% by weight of the nonwoven substrate, the binder represents between 7 and less than 10% by weight of the nonwoven substrate.

[0085] In some embodiments, the nonwoven substrate has a volume density, also referred to as sheet density, of at least 50 mg / cm3, preferably of at least 55 mg / cm3and most preferably of at least 60 mg / cm3, or at least 62 mg / cm3and / or a volume density of at most 140 mg / cm3, preferably at most 130 mg / cm3, even preferably at most 120 mg / cm3, most preferably at most 110 mg / cm3, preferably of at most 100 mg / cm3and most preferably of at most 90 mg / cm3.

[0086] The volume density of the nonwoven substrate can be obtained by dividing the areal density or grammage of the substrate by its thickness.

[0087] In some embodiments, the nonwoven material has an areal density, also referred to as grammage, of 40 to 65 g / m2, preferably of 45 to 60 g / m2and most preferably of 46 to 58 g / m2.

[0088] The areal density of a sheet of nonwoven substrate is determined by placing the sheet on a balance and measuring the weight. Afterwards the weight is divided by the area of the sample and the areal density / grammage is obtained. For example, the standard ISO 536:2019 can be used to determine the areal density of the nonwoven substrate.

[0089] The higher the areal / volume density of the nonwoven material for a given length, the higher the pressure drop of a filter that is manufactured using the nonwoven material. The natural fiber material for the nonwoven substrate may be selected from one or more of wood fibers, cotton fibers, leaf fibers, such as abaca or sisal fibers, bast fibers, such as jute, hemp, flax or kenaf fibers, and / or semi natural fibers such as viscose and / or lyocell fibers.

[0090] For example, the natural fibers may comprise or preferably consist of wood fibers selected from soft wood pulp or hardwood pulp, or a combination thereof. Preferably, the natural fibers comprise at least 50%, more preferably at least 70%, even more preferably at least 90%, even more preferably at least 95%, and most preferably 100% wood fibers. Preferably, the pulping process is a kraft pulping process, and the natural fibers are Southern bleached softwood kraft (SBSK) and / or Northern bleached softwood kraft (NBSK), wherein the wood pulp comprises at least 75% SBSK, preferably at least 85% SBSK, more preferably at least 95% SBSK and most preferably 100% SBSK (percentage in weight).

[0091] The average length of the natural fibers, according to some embodiments, is at most 3.5 mm, preferably at most 3.0 mm and most preferably at most 2.8 mm, and / or the average length of the natural fibers is at least 2.0 mm, preferably at least 2.3 mm and most preferably at least 2.5 mm.

[0092] An exemplary SBSK material suited for the filter is Golden Isles Treated fluff, grade 4623. This material has a fiber length of 2.68 mm and a basis weight of 765 g / m2.

[0093] The binder added to the natural fibers to form the nonwoven substrate may comprise at least one binding agent being a water-based polymer emulsion. The binder maybe selected from one or more of an aqueous copolymer dispersion of Ethylene Vinyl Acetate, EVA, and a Polyvinyl Acetate, PVAc, a cellulose derivative, such as ethyl / methyl cellulose, hydroxyethyl / -methyl cellulose and / or carboxymethyl cellulose and / or a polysaccharide (or a derivative of a polysaccharide) such as dextrin or starch.

[0094] In some embodiments, the binder is selected from one or more of an aqueous copolymer dispersion of Ethylene Vinyl Acetate, EVA, and a Polyvinyl Acetate, PVA. Preferably, the ratio of EVA to PVAc is between 70:30 and 30:70, more preferably between 60:40 and 40:60 and most preferably between 55:45 and 45:55. In some embodiments the ratio of EVA to PVAc is 50:50. A reduction in the level of phenol in the emissions was observed with filters made of a non-woven material with binder. The PVAc may be a PVAc stabilized by PVOH (vinyl alcohol polymer), dextrin and combinations thereof, more preferred a PVAc stabilized with PVOH. The advantages of the PVAc are high bonding properties with the natural fibers, fast setting of the binder and its compatibility with the EVA dispersion. An exemplary polyvinyl alcohol stabilized polyvinyl acetate (PVAc) is Vinamul® 8482, commercialized by Celanese.

[0095] An exemplary copolymer of the EVA is a copolymer of EVA stabilized with surfactant, emulsifier, cellulose derivative, PVOH, colloid and combinations thereof. The copolymer is hydrophilic so that it can easily wet the fiber material and has good adhesion properties. Preferred is a copolymer of EVA in an aqueous copolymer dispersion based on vinyl acetate and ethylene stabilized with surfactants. This copolymer provides a particularly neutral taste and has a low volatile organic compound (VOC) content.

[0096] To produce filters from the nonwoven sheet, the nonwoven sheet preferably has a reel width of 50 to 240 mm or too to 220 mm, preferably 70 to 170 or 120 to 180 mm.

[0097] Preferably, the nonwoven substrate is stored on one or more bales / pallets, preferably by a festooning process. In other words, the nonwoven material can be stored arranged as a continuous sheet, also indicated herein with the term “festoon”, preferably to form a bale. The continuous sheet of nonwoven material, or the bale formed by the continuous nonwoven material, can be arranged on a pallet or similar supports. It has to be noted that the term “continuous sheet” is herein used to indicate a single continuous sheet made as a one piece, as well as to indicate a sheet made up of spliced portions of nonwoven sheets. In other words, two or more portions of nonwoven material can be joined together to form a continuous sheet. For example, bobbins currently used in art can be spliced together to form a continuous sheet on nonwoven material. For example, the material of two or more bobbins, such as of 10 bobbins, can be “converted”, i.e. arranged, in a continuous sheet stored on a bale / pallet.

[0098] In the following, the festooning process for storing the nonwoven substrate, i.e. for storing the nonwoven substrate on a bale and / or a pallet, as well as the process for supplying the nonwoven substrate from the bale / pallet to the filter making apparatus for producing the filter, are described in more detail.

[0099] According to a first embodiment, a plurality of individual layers of a continuous sheet of nonwoven substrate are arranged on a pallet and / or bale. As mentioned above, the continuous sheet of nonwoven material, or the bale formed by the continuous nonwoven material, can be arranged on a pallet or similar supports.

[0100] One such example is shown in Fig. 4a. Adjacent portions (401a, 401b, 401c) of the continuous nonwoven sheet are arranged adjacent to each other in a substantially horizontal direction H, wherein the adjacent portions (401a, 401b, 401c) may overlap partially. The nonwoven substrate is arranged on the pallet or bale such that during removal of the nonwoven substrate from the pallet or bale, an individual first layer of the nonwoven substrate is removed before an individual second layer below the individual first layer of the nonwoven substrate is removed from the pallet or bale. Moreover, the nonwoven substrate is arranged on the pallet or bale such that portions (401a, 401b, 401c) of the nonwoven substrate that form the individual layer are removed from the pallet or bale in the substantially horizontal direction H. Moreover, each of the individual layers of nonwoven material may extend over the total area of the pallet or bale. The nonwoven substrate arranged as described above, preferably by means of a festooning process (that can be carried out at the same plant where the filter is produced, or that can be carried out previously at a different plant where the filter is produced), is provided for production of the filter in direction P. It has to be noted that the festooning process to create the bale is preferably carried out in a non-woven process plant, e.g. of a non-woven supplier, but it is not excluded that the festooning process to create the bale can be carried out at the same plant where the filter is produced.

[0101] In a second embodiment, the nonwoven substrate is provided on the pallet and / or bale, wherein individual (420a, 420b) stacks of nonwoven material are arranged next to each other. As mentioned above, the continuous sheet of nonwoven material, or the bale formed by the continuous nonwoven material, can be arranged on a pallet or similar supports. One such example is shown in Fig. 4b. In this example, adjacent portions (402a, 402b) of the continuous nonwoven sheet are arranged above / below each other in a substantially vertical direction V, wherein the adjacent portions may overlap substantially completely. While in the previous example adjacent portions (402a, 402b) of the continuous nonwoven sheet are arranged adjacent to each other forming individual layers, in this example, adjacent portions (402a, 402b) of the continuous nonwoven sheet are arranged above / below each other, forming the individual stacks (420a, 420b) of the nonwoven substrate. The nonwoven substrate is arranged on the pallet or bale such that during removal of the nonwoven substrate from the pallet or bale, an individual first stack (420a) of the nonwoven substrate is removed before an individual second stack (420b) adjacent to the individual first stack (420a) of the nonwoven substrate is removed from the pallet or bale. Moreover, the nonwoven substrate is arranged on the pallet or bale such that portions (402a, 402b) of the nonwoven substrate that form the individual stacks (420a, 420b) are removed from the pallet or bale in the substantially vertical direction V. Moreover, each of the individual stacks (420a, 420b) of nonwoven material may extend over the total height of the nonwoven substrate arranged on the pallet or bale. The nonwoven substrate arranged as described above, preferably by means of a festooning process, is provided for production of the filter in direction P. It has to be noted that the festooning process to create the bale is preferably carried out in a non-woven process plant, e.g. of a nonwoven supplier, but it is not excluded that the festooning process to create the bale can be carried out at the same plant where the filter is produced.

[0102] Providing the nonwoven substrates, stored in the form of a bale and / or on pallet using festooning process, has the advantage of reduced area requirement in a production facility compared to other widely used arrangements, such as a rolling process, where the nonwoven sheet is arranged on one or more bobbins.

[0103] In Figure 5 the difference in space requirement between a rolling process [a] and the feeding of the nonwoven substrate stored on a bale / pallet by a festooning process [b] for manufacturing the filter is illustrated. Typically, in the rolling process [a], at least two large bobbins (501) are provided for providing the nonwoven substrate to the production facility. Typically, the nonwoven substrate is fed from the bobbins (501) into a buffer (502) before it is transferred into the crimping unit (510). When there is the need to change the bobbin it is necessaiy to stop its rotation movement, the buffers allows the splicing of the nonwoven substrate from the bobbin currently in use to the subsequent bobbin, while allowing the manufacturing process of the filter to continue without interruption.

[0104] Contrary to this, when the nonwoven substrate has been stored in a bale / pallet by a festooning process [b], the nonwoven substrate provided on bales or pallets (503) can be fed (pulled from the bale / pallet) directly into the filter manufacturing process, e.g. in a crimping unit (510) thereof, for production of the filter. Due to the nonwoven substrate being provided on a bale or pallet, the buffer for splicing the substrate is at least reduced, or in some embodiments it is not necessary, in the festooning process. In fact, it is possible to connect the nonwoven substrate from the bale / pallet currently in use to the leading end of the nonwoven substrate of the subsequent bale / pallet to be used, well before the trailing end of the nonwoven substrate of the bale / pallet currently in use is fed to the crimping unit. In other words, the splicing of the nonwoven substrate of two bales / pallets can be easily carried out since the trailing end of the nonwoven substrate is always available, contrary to the bobbins arrangement wherein the nonwoven substrate is rotating thus to operate on the nonwoven substrate or on the bobbin it is necessary to stop its rotational movement.

[0105] This also leads to significantly less space requirement in the production facility, when compared to the space required for the rolling process. To this regard it has to be noted that the festooning process allows to store on a bale a nonwoven substrate having a length that is usually stored in about io bobbins of the known art.

[0106] Advantageously, the festooning process for storing the nonwoven substrate for example in the form of a bale, allows to provide filters comprising nonwoven material with a similar layout in the production facility as for conventional filters, e.g. cellulose acetate filters, while providing less space requirements and a more efficient exchange of a subsequent feeding bale / pallet that does not require (or at least reduces) the buffer required in the know art to compensate for the bobbins rotation interruption.

[0107] To improve the quality of the filter obtained by the nonwoven substrate, in an exemplary embodiment, the nonwoven substrate is crimped before being formed into the filter. In this exemplary embodiment, the nonwoven substrate is crimped in the machine direction of a crimping machine with a crimping depth of 0.2 to 1.2 or 0.2 to 1.0 mm, preferably of 0.5 to 1.0 mm or 0.5 to 0.9 mm to obtain straight crimping grooves. The above ranges provided good filter properties without causing any breaks and cracks in the nonwoven substrate.

[0108] While the crimping process can increase the filter quality, for some embodiments this additional step can be removed from the manufacturing process, and the filter can be formed directly from the nonwoven substrate.

[0109] The crimped nonwoven substrate may then be rolled from the sheet into the typical cylindrical filter shape / rod-shape by rolling the sheet about the longitudinal axis of the filter. In other embodiments, the crimped nonwoven substrate is pressed into the typical cylindrical filter shape / rod-shape. While cylindrical / rod shaped filters are most common in the art, the crimped nonwoven substrate may also have a rectangular shape, a conical shape, a spherically shape or any other shape that fits into the smoking article / aerosol generating device it is used for. Additionally, flavoring agents may be added to the filter to provide a more pleasant smoking experience for the consumer.

[0110] To be compatible with commonly used smoking articles / aerosol generating devices, the circumference of the filter (including filter wrapper thickness) is preferably between 16 to 28 mm or 20 to 28 mm, more preferably between 22 to 26 mm, even more preferably 24 to 25 mm and most preferably of 24.2 mm. For example, the circumference may be between 16 to 28 mm, for example 16.8 mm, or about 16 to 26 mm, for example 21.5 mm, or about 16.8 to 24.20 mm.

[0111] To allow handling and contain the filtering substrate, the rolled nonwoven substrate may be wrapped by a wrapping paper with a basis weight of 24 to 120 gsm or 25 to 50 gsm, or 27 to loogsm and / or a thickness of 0.03 to 0.125 mm or 0.03 to 0.06 mm. For example, a plug wrap of 0.100 mm or 0.110 mm or 0.120 mm may advantageously provide an improved hardness of the filter.

[0112] Preferably a filter obtained with the above material has a density of 100 to 200 mg / cm3, preferably between 120 and 160 mg / cm3, for example 150 mg / cm3, wherein the pressure drop at the filter is between 1.3 and 4.5 mmWC / mm, preferably between 1.8 and 3 mmWC / mm, preferably determined according to the conditions described in ISO 6565:2015. The filter density may vary depending on the circumference of the filter. For example, when the filter circumference is about 16.8 mm, the filter density may be comprised between 106 and 211 mg / cm3, wherein the pressure drop is comprised between 2.78 and 4.44 mmWC / mm. When the filter is about 21.5 mm, the filter density may be comprised between 130 and 208 mg / cm3wherein the pressure drop is comprised between 2.04 and 3.70 mmWC / mm. When the filter is about 24.2 mm, the filter density may be comprised between 123 and 184 mg / cm3wherein the pressure drop is comprised between 1.67 and 4.44 mmWC / mm.

[0113] According to an embodiment of the present invention, a sheet of nonwoven material is folded into a plurality of layers. In some embodiments, the plurality of layers are arranged as described with reference to Figs. 4a and 4b.

[0114] In an exemplary embodiment, the sheet of nonwoven material is a continuous sheet of nonwoven material folded into a plurality of layers (431, 432, 433, 434, 435). The plurality of layers (431, 432, 433, 434), 435 are stacked onto each other in the vertical direction V, preferably on top of a pallet 410, such as a wooden pallet, a plastic pallet or a metal pallet. Folding edges 440 of the continuous sheet of the nonwoven material, at which the individual layers of the plurality of layers (431, 432, 433, 434, 435) are formed, are arranged at opposite sides of the bale 400 in a horizontal direction H’. The horizontal direction H’ is perpendicular to the vertical direction V’. The vertical direction V refers to the direction in which the individual layers are stacked on top of each other.

[0115] According to possible embodiments, the folding edges (440) of at least two individual layers of the plurality of layers (431, 432, 433, 434, 435) are superimposed relative to each other in the horizontal direction H’, so that the folding edges are not arranged one above the other, i.e. there is a distance between the folding edges of superimposed layers in the horizontal direction.

[0116] More in detail, according to a possible embodiment, a folding edge (440) of a first layer (431) of the plurality of layers (431, 432, 433, 434, 435) is positioned at a first distance (a) relative to a folding edge (440) of the second layer (432), a folding edge (440) of a third layer (433) is located at a second distance (b) relative to the folding edge (440) of the second layer (432), a folding edge (440) of a fourth layer (434) is located at a third distance (c) relative to the folding edge (440) of the third layer (433), and a folding edge (440) of the fifth layer (435) is located at a fourth distance (d) relative to the folding edge (440) of the fourth layer (434). The arrangement of individual layers of the plurality of layers (431, 432, 433, 434, 435), may form a predefined pattern. Preferably, this predefined pattern is repeated. For example, a predefined pattern formed by N individual layers (N being an integer) maybe repeated every N layers (e.g., if N=5, then the pattern may be repeated every 5 layers). In some examples, a predefined pattern is characterized by at least 2, preferably at least 3, more preferably at least 4, even more preferably at least 5 folding edges that are superimposed to each other. In the predetermined pattern according to the invention, having a predefined number of folding edges superimposed to each other means that there are a predefined number of individual positions for allocating folding edges of layers in a pattern in the H’ direction.

[0117] In other words, in the predetermined pattern according to the invention, a predefined number of folding edges are superimposed to each other such that there is a distance between the folding edges of superimposed layers in the horizontal direction.

[0118] For example, for N=3 there may be at most 3 superimposed folding edges. In this case, each of the folding edges in a predefined pattern has a different location in the H’ direction. One such example is shown in Fig. 6, which will be discussed in more detail below. In this example, the repetitive pattern formed by three layers has three superimposed folding layers (i.e., each of the folding edges are located at a distance to each other in the H’ direction / none of the folding edges in the pattern are on top of each other in the H’ direction). Another example is shown in Fig.7, where N=4, and 3 folding edges are superimposed to each other. Here, the folding edge of the fourth layer (434) and of the second layer (432) are on top of each other (the edges do not have a substantial distance between them in the H’ direction).

[0119] Generally speaking, any predefined pattern formed by N layers may repeat until an nthlayer. In one example, n is an integer of at least 7. In such an example, the nthlayer is on top of the n-ithlayer and the folding edge (440) of the nthlayer is located at a distance m relative to the folding edge (440) of the n-ithlayer. The individual arrangements may depend on the material used and its corresponding characteristics. For example, a material that is more susceptible to deforming may require a predefined pattern with more superimposed folding edges, wherein a material with a low tensile strength might require less superimposed folding edges. For example, the nthlayer may be arranged above the n-2thlayer, the n-3thlayer, the n-4thlayer, the n-5thlayer, the n-6thlayer, the n-7thlayer and so on, wherein arrangements according to the “ns-arrangemenf’ (i.e., an alternating structure of two layers) to the “n-10-arrangement" (i.e., a pattern with 10 superimposed folding edges) are preferred. That is, the applicant found that pattern with 2 to 10 superimposed folding edges showed the best results for the nonwoven material of this application. The example shown in Fig. 6 corresponds to an n-3- arrangement, and the example of Fig. 7 corresponds to a n-4-arrangement (i.e., the first layer is positioned below the fifth layer, the second layer is positioned below the sixth layer (not shown), and so on).

[0120] As set forth above, the individual layers of the plurality of layers are formed by folding the continuous sheet of nonwoven material at folding edges. This forming of the individual layers is illustrated in Fig. 6 in more detail. Two sheet portions (431a, 431b) of the continuous sheet of nonwoven material are formed by folding the continuous sheet of nonwoven material at folding edge 440, wherein the two sheet portions (431a, 431b) are connected to each other via the folding edge (440). Two such sheet portions that are connected via folding edge 440 may form one of the plurality of layers (431, 432, 433, 434). In the example shown in Fig. 6, the folding of the plurality of layers (431? 432, 433, 434) of the bale is illustrated only for one of the two opposite sides of the bale. The plurality of layers (431, 432, 433, 434) illustrated in Fig. 6 may extend further in a direction towards the opposite side of the bale (400) / pallet (410) (not shown). The drawing shown in Fig. 6 is for illustrative and descriptive portion and the length of the plurality of layers (431, 432, 433, 434) are not intended to limit the lengths of the plurality of layers (431, 432, 433, 434). In fact, the same folding of the continuous sheet of nonwoven material may also be performed at the other of the two opposite sides of the bale (4oo) / pallet (410). In such an example, on the opposite sheet of the bale (not shown in Fig. 6) sheet portion (431a) maybe located below an alternative first layer formed by folding two sheet portions at the opposite side. Here, the first layer may be formed by the sheet portion (431b) and a sheet portion associated with the second layer of the side of the bale shown in Fig. 6, wherein the sheet portion (431b) and the sheet portion associated with the second layer of the side of the bale shown in Fig. 6 may be connected via a folding edge (not shown) on the opposite side of the bale (4oo) / pallet(4io).

[0121] As discussed above, the possible example depicted in Fig. 6 comprises a pattern formed by three individual layers (431, 432, 433) that repeats eveiy three layers (a fourth, fifth and sixth layer form a similar pattern as the 1st, 2ndand 3rdlayer). Moreover, the threelayered pattern has three superimposed folding edges, i.e., each of the three folding edges of the pattern are located at a distance (a, b, c) to each other in the H’ direction.

[0122] The example of Fig. 7 shows five layers (431, 432, 433, 434, 435). It has to be noted that in figure 7 each layer (431, 432, 433, 434, 435) is only schematically shown, in fact, the two sheets portions of the continuous sheet of nonwoven material that are formed by folding the continuous sheet of nonwoven material at folding edge, so as to form a layer (as previously disclosed for example in connection to figure 6), are not shown in figure 7 wherein the layer is schematically shown as a single horizontal element. Further layers (not shown) may be positioned on top of the fifth layer (435). At least a first layer

[0123] (431) of the plurality of layers (431, 432, 433, 434, 435) is arranged on a second layer

[0124] (432) of the plurality of layers (431, 432, 433, 434, 435). In the horizontal direction H’, a folding edge (440) of the first layer (431) is positioned at a first distance (a) relative to a folding edge (440) of the second layer (432). In the example shown in Fig. 7, a folding edge (440) of the third layer (433) is located at a second distance (b) relative to the folding edge (440) of the second layer (432). Further, in the example shown in Fig. 7, a folding edge (440) of the fourth layer (434) is located at a third distance (c) relative to the folding edge (440) of the third layer (433), and a folding edge (440) of the fifth layer (435) is located at a fourth distance (d) relative to the folding edge (440) of the fourth layer (434). In this example, the first (a), second (b), third (c) and fourth (d) distances are substantially similar. Preferably, the distances between the plurality of layers on the one side are similar to the distances between the plurality of layers on the opposite side. However, the distances may vary.

[0125] The particular example shown in Fig. 7 comprises a repeated pattern of four layers (431? 432, 433, 434), wherein the fifth layer (435) may already be part of a repeated pattern of another four layers on top of the first pattern formed by the four layers (431, 432, 433, 434). In this pattern of four layers (431, 432, 433, 434), three of the folding edges are superimposed to each other, wherein the folding edges corresponding to the second and fourth layer are located at the same position in the H’ direction (the folding edges are on top of each other). As can be seen in Fig. 7, the folding edges (440) of the plurality of layers (431, 432, 433, 434, 435) in this particular example are arranged in a substantially zigzag-shape on the at least one side of the bale, wherein the zigzag-shape is formed by at least two individual layers of the plurality of layers (431, 432, 433, 434, 435)- The example shown in Fig. 7 is formed by five individual layers (431, 432, 433, 434, 435) of the plurality of layers. In this example, the first to third layer form the extending portion of the zigzag-shape, and the third and fourth layer form the retracting portion of the zigzag-shape. Starting with the fifth layer (435), this pattern is repeated (the remaining layers of the second pattern are not shown in Fig. 7). In the example shown in Fig. 7, the folding edge (440) of the first fight layer is on top of the folding edge (440) of the first layer and the folding edge (440) of the fourth layer is on top of the folding edge (440) of the second layer.

[0126] In figures 6 and 7, only one side of the two opposite sides of the bale (4oo) / pallet (410) are shown. The arrangement of layers at the opposite side of the bale (400) / the pallet (410) maybe different to the arrangement of layers at the side shown in the drawings. That is, the length of each of the layers may vary and thus the distances on the opposite side of the bale may be different to the first, second, third, fourth and fifth distance. In fact, in some embodiments, it is preferred that subsequent folding edges (440) may be on top of one or more previous folding edges (440), as long as some other folding edges (440) are arranged at a distance. For example, in one example, the folding edge (440) of the first layer (431) may be arranged at the first distance (a) to the folding edge (440) of the second layer (432) in the horizontal direction H’. In this example, the folding edge (440) of the third layer (433) may be arranged above the folding edge of the second layer (432), and the folding edge (440) of the fourth layer may be arranged at a second distance relative to the folding edges (440) of the second and third layers (432, 433) in the horizontal direction H’. In this example, the folding edge (440) of the fourth layer may be arranged at a further distance (in the horizontal direction H’) to the edge of the first layer (431) than to the folding edges (440) of the second and third layer (432, 433). In other examples, the folding edge (440) of the fourth layer be above the first layer (431), or between the folding edges (440) of the second and third layer (432, 433) and the folding edge (440) of the first layer (431) in the horizontal direction H’. Such pattern may be repeated and / or combined with other patterns described herein.

[0127] Preferably, the first distance (a) is at least 1 mm, preferably at least 2 mm, more preferably at least 5 mm, even more preferably at least 7.5 mm, and most preferably at least 10 mm, and / or the first distance (a) is at most 20 mm, preferably at most 17.5 mm, more preferably at most 15 mm, even more preferably at most 12.5 mm, and most preferably at most 100mm.

[0128] According to the invention, an edge being below another edge corresponds to being arranged such that in the horizontal direction H’, the distance between the edges is substantially zero. The same applies for an edge being above another edge. This es shown, for example, in Fig. 7, where the edge of the fourth layer (434) on the left side of the figure is located above the edge of the second layer (432) (the edge of the second layer being below the edge of the fourth layer), and the folding edge (440) of the fifth layer (435) is located above the folding edge (440) of the first layer (431).

[0129] Another aspect of the invention relates to a method for providing a bale as described above. The method comprises a step of folding the continuous sheet of nonwoven material into the plurality of layers stacked onto each other in the vertical direction (V’) on a surface, preferably on the pallet, such that folding edges (440) of the individual layers of the plurality of layers are located on a first side of the bale and on a second side of the bale opposite to the first side, wherein folding the continuous sheet of nonwoven material further comprises folding at least a first layer (431) and a second layer (432), wherein on at least one of the first and second side of the bale, the first layer (431) is positioned on the second layer (432) such that a folding edge (440) of the first layer (431) is positioned at a first distance (a) to a folding edge (440) of the second layer (432) in the horizontal direction (H’) substantially perpendicular to the vertical direction V’. Folding the continuous sheet of nonwoven material may further comprise folding a third layer (433) on the second layer (432), a fourth layer (434) on the third layer (433) and / or a fifth layer (435) on the fourth layer (434), wherein a folding edge (440) of the third layer (433) is positioned at a second distance (b) to the folding edge (440) of the second layer (432), a folding edge (440) of the fourth layer (434) is positioned at a third distance (c) to the folding edge (440) of the third layer (433), and the folding edge (440) of the fifth layer (435) is located at a fourth distance (d) to the folding edge (440) of the fourth layer (434), in the horizontal direction H’. An exemplary bale obtained by this method is shown in Fig. 7 and described above. Preferably, the plurality of layers (431, 432, 433, 434, 435) are folded such that the distances as described with respect to Fig. 7 above are achieved. In some embodiments, the continuous sheet of nonwoven material is folded such that the above-described shapes and arrangements of layers are obtained.

[0130] For folding the bale any folding means known in the art may be used. In some examples, an automatic folding apparatus comprising a controller may be used. In some embodiments, a computer program may comprise instructions that cause a processor to execute the above-described method, preferably the instructions may case a folding means to fold the nonwoven material as described above. Such computer program may be stored on a non-transitory storage medium.

[0131] Further embodiments of the invention relate to a bale obtained according to the above method and or to a filter having any of the above-described properties (i.e., the characteristics described with respect to Figs. 1 to 3) obtained from a bale according to any of the embodiments as described with respect to Figs. 4a, 4b, 5, and / or 6.

[0132] EXEMPLARY NONWOVEN SUBSTRATES

[0133] In the following, worked examples of nonwoven substrate are discussed in detail. Table 1 shows four samples (lots 2, 4, 7 and 8) of nonwoven substrates that were manufactured considering the above-described properties.

[0134] Lots 2, 4, 7 and 8 were manufactured with a fiber content in the range of 86.9 to 91.8 %, and a corresponding binder content in the range of 8.2 to 13.1 %. From the four samples, lot 4 has the lowest binder content with 8.2%, followed by lot 7 with 8.5%, then followed by lot 2 with a binder content of 9.5% and lot 8 with the highest binder content of 13.1%.

[0135] For each of the samples, the areal density, the thickness, and the dry tensile strength were measured. To measure the tensile strength, a 5 cm strip of nonwoven substrate was cut off from the respective nonwoven substrate and clamped into a tensile strength measuring device. For example, a Zwick Roell tensile strength measurement device may be used, wherein the tensile strength is preferably measured under the testing conditions defined in ISO 9073-3. However, other methods are also possible, such as the measurement method defined in ISO 9073-18:2007. In this particular example, the measurement method defined in ISO 9073-3 was conducted. The tensile strength measurement device applied a force to each end of the 5-cm strip until the breaking point of the strip was reached and teared / broke. The required force and the elongation of the strip were then measured.

[0136] Table 1 below shows the measurement results with regards to the densities, the thickness, and the tensile strength of the respective samples (lots 2, 4, 7 and 8). The sheet density was calculated by dividing the areal density by the thickness.

[0137] TABLE 1

[0138] As can be seen from table 1, the areal densities of the samples were within the range of 44.4 to 81.63 mg / cm3. The nonwoven substrate of lot 7 had the lowest areal density of 46.99 g / m2, followed by lot 4 with an areal density of 50.61, then by lot 8 with an areal density of 55.58 g / m2and lot 2 with the highest areal density of 55.58 g / m2. The respective thicknesses of the samples were within the range of 0.62 to 1.19 mm. From the four samples, lot 4 had the lowest thickness with a thickness of 0.62 mm, followed by lot 7 with a thickness of 0.78 mm, then by lot 2 with a thickness of 0.92 mm and lot 8 with a thickness of 1.19 mm.

[0139] The tensile strengths measured for the samples are within the range of 14.2 to 28.2. From the four samples, lot 7 has the lowest tensile strength with 14.2 N / 5 cm, followed by lot 8 with a tensile strength of 14.7 N / 5cm, then followed by lot 2 with a tensile strength of 18.0 N / 5 cm and lot 4 with the highest tensile strength of 28.2 N / 5 cm.

[0140] The above shows that generally, a high volume / sheet density of the nonwoven result in a high tensile strength of the material. However, the tensile strength of the filter depends also on the amount of binder and the thickness of the material. This can be seen in table 1, where lots 2 and 7 have similar volume densities but the tensile strengths vary significantly.

[0141] To show the effects of the particular parameters on the tensile strength, a second and a third batch of samples were prepared. In Figures 1 and 2, the tensile strength of the respective samples of the second and the third batch of nonwoven substrates are shown with respect to the respective thickness of the sample and the binder content. In Figure 1, the substrates in zones 1 and 4 showed tensile strengths that are sufficient for filter production, the substrates in zone 2 showed tensile strengths that are somewhat sufficient for filter production, and the substrates in zone 3 showed tensile strengths that are not sufficient for filter production, as they have an increased risk of tearing. Similarly, in Figure 2, zone 1 shows substrates with sufficient tensile strengths, zone 2 shows substrates with somewhat sufficient tensile strengths and zone 3 shows a substrate that does not have sufficient tensile strength for filter production.

[0142] As can be seen from Figure 1 in particular, if the areal density and the binder content are constant, the tensile strength decreases as the thickness decreases, which confirms the findings shown in table 1, where it was observed that as the volume density increases, the tensile strength increases. Furthermore, if the thickness, and thus the sheet / volume density is kept constant, the tensile strength increases with the binder content. Accordingly, the areal density, the thickness, and the binder content of the nonwoven all directly influence the resulting tensile strength.

[0143] Returning to the samples of table 1, while each of the sheets of nonwoven substrate from each of lots 2, 4, 7 and 8 showed a sufficient tensile strength for producing filters, producing lots 7 and 8 was less productive compared to lots 2 and 4. This was because amounts of binder were leaking out of the substrates during production, which contaminated the machines used for producing the nonwoven sheet. This in turn led to the reduced productivity, as additional cleaning processes had to be added to the operation for producing lots 7 and 8.

[0144] The amount of binder leaking out of a nonwoven substrate depends also on the binder content, the thickness of the material, the areal density and thus also on the sheet / volume density. For example, a low volume density which can hardly prevent binder from escaping the nonwoven material increased the amount of binder leaking out of the device. Similarly, increasing the binder content while other parameters are constant also increases the amount of binder leaking out of the nonwoven substrate. Additionally, if the binder content and the volume density are constant, a lower thickness increases the effect of leakage, as less textile material is provided to prevent the binder from leaking.

[0145] Accordingly, while the parameters influencing the tensile strength suggest that a high binder content is desired, leaking also increases with a high binder content, which is to be prevented. Moreover, a too low thickness requires high pressure during production, which results in a non-uniform web of the nonwoven material. Accordingly, a nonwoven substrate with a relatively low thickness, such as in the range of 0.5 to 0.7 mm (high sheet / volume density) and / or with a relatively low binder content such as in the range of 10% -7% is most preferred.

[0146] FILTER PROPERTIES

[0147] From the nonwoven sample material, filters were formed by crimping the sheets of nonwoven material, rolling the crimped sheets into a rod-like shape, and wrapping the rod-like shaped nonwoven sheet with a wrapping paper, as described above.

[0148] The obtained filters were then subjected to pressure drop and firmness / hardness measurements to determine whether the filters, obtained according to the above describe method, show similar filtering properties as filters known in the art.

[0149] The firmness / hardness and the pressure drop of the filters were measured using the hardness module (SODIM-H) and the pressure drop module (SODIM-PDVM) of the Sodiline measurement device. In the pressure drop module a critical flow orifice and a vacuum generator were provided in a laminar flow system. The vacuum generator was activated, and the pressure drop at the filter was measured (in mmWC). In the hardness module a mobile jaw applied pressure to the side of the filter (in axial direction of the cylinder-shaped filter) and the amount of compression was recorded (amount of deformation in tenth of mm).

[0150] Figure 3 shows the respective test results of a plurality of produced filters. The measured pressure drop of the filters is plotted against their respective measured hardness. In the measurement, a filter was subjected to a load of 350g for 5s in SODIM- H. It can be seen that the pressure drop at the filter decreases as the filter’s firmness increases. Most preferred are pressure drops in the range of 1.3 to 5 mmWC / mm or 1.3 to 4.5 mmWC / mm, preferably between 1.8 mmWC / mm and 4.5 mmWC / mm or 1.8 and 3 mmWC / mm. Accordingly, the respective firmness of the filters are preferably in the range of 2.5 mm to 1.3 mm, more preferably in the range of 2.3 mm to 1.5 mm. These firmness ranges are achieved when filters are prepared as described above.

[0151] Thus, the filters obtained from the nonwoven material described above provide a pleasant experience for the user. Moreover, due to the high tensile strength of the material, the breaking of the nonwoven sheet is prevented.

[0152] FILTER DENSITY

[0153] The following tables provide examples of the characteristics of nonwoven filters of the invention (in particular, the volume density of the filter is calculated for different circumferences and different sheet widths). The volume density of the filter is calculated by dividing the weight of the filter substrate (i.e., the weight of the gathered sheet of nonwoven but not including the weight of the plug wrap) by the external filter cylindrical volume “Vc” (Vc= Filter length x II (filter radius)2), where the radius comprises the thickness of the plug wrap of the filter.

[0154] 1. Super Slim nonwoven filter: a) Example 1: b) Example 2:

[0155]

[0156] 2. Slim nonwoven filter: a) Example 1: b) Example 2:

[0157] 3. King size nonwoven filter:

[0158] FILTER PRESSURE DROP The following tables provide examples of the pressure drop of the nonwoven filters of the invention according to different circumferences given in the previous examples (i.e. filter formats).

[0159] 1. Super slim filter: 2. Slim filter:

[0160] 3. King size filter:

[0161] The filter of the invention may comprise a capsule containing flavourant such as menthol and the like. The encapsulated flavourant may have a core comprising liquid, powder or gel encapsulated by a shell, sheet or coating forming a barrier material. The encapsulated flavourant can be a capsule which can be ruptured to release the flavourant before or during use. The barrier material may be frangible or breakable. The capsule can be crushed or otherwise fractured or broken by the user to release the encapsulated flavourant. Typically, the capsule is broken immediately prior to smoking or heating being initiated. The term "breakable capsule" refers to a capsule, wherein the shell can be broken by means of a pressure to release the core; more specifically the shell can be ruptured under the pressure imposed by the user's fingers (or any other pressure creating means) when the user wants to release the core of the capsule.

[0162] The filter may comprise additives such as charcoal substrate. The substrate may be embedded in the nonwoven material. The charcoal maybe added as particles or beads. The charcoal may be sprayed on the nonwoven material with binder to make it impregnate the nonwoven material. The substrate obtained after spraying the filter paper is an impregnated charcoal substrate. With this method, the charcoal in the impregnated charcoal nonwoven may be standard activated carbon.

[0163] A filter assembly may be formed of more than one filter of the invention. For example, several segments of filters are arranged sequentially. The segment may have the same composition or a different composition. For instance, a first segment may comprise an encapsulated flavourant and a second segment may comprise additives (e.g., charcoal substrate) or no additive. Filter segments maybe adjacent one another (i.e., abutting) or may be separated by a cavity formed by a paper tube and / or a paper wrapper. The cavity may contain an encapsulated flavourant as aforementioned.

[0164] A filter of the invention may be positioned at the upstream end of an aerosol generating article or smoking article, for example, as described in EP3861868A1.

[0165] The filter may be used in a cigarette, an e-cigarette, a vaporizing device, or other known smoking / aerosol generating articles known in the art. The filter may be used in combustion systems, where an aerosol generating substance is burnt, or heat-not-burn systems, where the aerosol generating substance is heated such that an aerosol is generated from the substance, without burning the substance. The aerosol generating substances may be any substance containing tobacco, nicotine, flavoring agents and / or other substances capable of providing an inhalable aerosol to a user.

[0166] SMOKING OR AEROSOL GENERATING ARTICLES

[0167] The following tables provide examples of the characteristics of the tipping papers selected for producing aerosol generating articles with the nonwoven filters of the invention according to different circumferences (i.e., filter formats) presented above. The tipping paper is arranged to attach the filter and the aerosol generating segment.

[0168] Combustible aerosol-generating articles (“cigarettes”)

[0169] An example of combustible aerosol-generating article according to the present embodiment is shown in Fig. 8. A combustible article 8 comprises an aerosol generating segment i and a filter 2 of the invention arranged adjacent to the aerosolgenerating segment 1. The aerosol-generating segment 1, in the form of a rod, includes a filling 3 containing a tobacco substrate suitable for smoking and a first wrapper 4 (usually a paper layer) wrapped around the filling 3. The filter 2 includes a nonwoven substrate 5 of the invention and a second wrapper 6 (i.e., plug wrap as preferably defined earlier) wrapped around the nonwoven substrate 5. The aerosol-generating segment 1 and the filter 2 are connected by a tipping paper 7 wrapped around the aerosol-generating segment 1 and filter 2. The tipping paper member 7 may comprise a ventilation region (not shown) in the outer peripheral portion thereof. The ventilation region may comprise one or more circumferential perforations, and for example, rows of 10 to 40 holes maybe formed. The perforations or holes are preferably provided through the filter wrapper 6 or the filter wrapper (i.e., plug wrap) or the filter wrapper maybe made of porous paper to allow air in the filter at a desired ventilation level (e.g., 20-80%). The ventilation holes arranged allow air to be drawn into the filter 2 through the ventilation holes upon inhalation. By diluting the mainstream smoke with outside air through the ventilation holes, a desired tar value can be achieved and a proper cooling of the smoke at the mouth end of the article can be obtained.

[0170] The following table provides comparative examples of filter rods and cigarettes according to Fig. 8 respectively with cellulose acetate filters and nonwoven filters of the invention and for two different tar levels. It is apparent from these results that the pressure drop of the cigarette of the invention is comparatively lower than the one of the cellulose acetate filter whereas the firmness is similar.

[0171]

[0172] Table i

[0173] Table 2

[0174] In all of these tests, the firmness of the filters is measured using the hardness module (DD60A) proposed by Borgwaldt ® GmbH. To determine the firmness of filter rods, 10 test samples are placed on the receptacle and the samples are pressed with a 3 kg load weight for 5 seconds.

[0175] The measured firmness is calculated each time by the formula:

[0176] Measured Firmness = 10 x (Measured Diameter - Mean Value). where the Measured Diameter is the average diameter of the samples, and the Mean Value is the average remaining heights of the samples in the apparatus.

[0177] The mean of the 10 results of the Measured firmness is calculated. It can thus be expressed in tenths of a millimeter or lo 'mm.

[0178] The aerosol generating article according to the embodiment of figure 9 may further have at least one or more upstream segment, in addition to the filter. The other (“second”) segment, for example, maybe a cooling substrate such as polylactic acid or a hollow structure such as a paper tube, and the like. The second segment may comprise the ventilation region as aforementioned. The second segment can also contain adsorbents such as activated carbon, silica gel, or zeolite, and can contain liquid fragrance, solid fragrance, or fragrance supported on a carrier. The second segment may be a second filter comprising nonwoven substrate having different characteristics from the first (nonwoven) filter 2. The second filter 9 may contain a breakable flavor capsule with a core-shell structure, in which liquid fragrance is wrapped in a shell of gelatin, a polysaccharide, or biodegradable resin. The filter 2 and second segment 9 are each individually wrapped with a plug wrapper, and they are attached together by an outer plug wrapper io to form a filter assembly. The tipping paper 7 provides attachment of the filter assembly 11 to the aerosol generating segment 3. A ventilation region (not shown) may be provided through the wrapper and tipping paper in the region of the second filter.

[0179] In another variant to the two previous embodiments, a segment may be positioned downstream of the nonwoven filter such as a hollow paper tube to provide a rigid mouthpiece element.

[0180] Non-combustible aerosol-generating articles (“heat-not-burn articles”)

[0181] An example of the non-combustible aerosol generating article of the present embodiment is shown in Fig. 10. The aerosol-generating article may be configured to be suitable for delivering an aerosol when inserted in an electrical heating device, e.g., as described in EP4233577. The article comprises an aerosol generating segment 1 and a mouthpiece segment 13 connected by a tipping paper as defined earlier. The mouthpiece segment 13 has a cooling segment or spacer 14, an optional center hole segment 15, and filter 2 comprising a nonwoven substrate according to the invention. Upon inhalation, the aerosol generating segment 1 is heated, and the aerosol generating compounds (aerosol forming material, flavour, water, nicotine, etc.) contained in the aerosol generating segment 1 are vaporized and transferred to the mouthpiece segment 13 by inhalation and to the mouth end of the article.

[0182] The cooling segment 14 maybe, e.g., a tubular member 16 and / or a polylactic filling. The tubular member 16 can be, for example, a paper tube made of multi-layered cardboard processed into a cylindrical shape. A ventilation region, e.g., one or more rows of circumferential holes. The presence of perforations 17 allows outside air (according to a desired ventilation level e.g., 20-80%) to be introduced into the cooling segment 14 upon inhalation. This causes an aerosol vaporization component generated by heating flavor-generating segment 1 to contact the outside air and lower the temperature of the aerosol vaporization component, whereby vapor condenses in tiny droplets to form the aerosol. The diameter (span length) of perforation 17 is not particularly limited, and maybe, for example, 0.2 to 1.5 mm. The number of perforations 17 is not particularly limited, e.g. can be one, two or 30.

[0183] The center hole segment 15 may be connected to filter 2 by an outer plug wrapper 20 or directly by the tipping paper 21 (in which case the outer plug wrapper is omitted). In addition, the aerosol-generating segment 1, cooling segment 14, the connected center hole segment 15 and filter 2, are connected by the tipping paper 21, e.g., as defined earlier.

[0184] The axial length of the aerosol-generating article according to the present embodiment, i.e., the horizontal length in Fig. 10, is not particularly limited, and is preferably between 40 and 90 mm, more preferably 50 to 75 mm, and still more preferably 50 to 65 mm, e.g. 60 mm. Moreover, the circumference length of the aerosol-generating article may be of 16 to 25 mm, more preferably 20 to 24 mm, and still more preferably 21 and 23 mm, e.g. 21.45. For example, an aspect of the length of about 20 mm of the aerosol generating segment 1, the length of 20 mm of cooling segment 14, the length of 8 mm of center hole segment 15, and the length of 7 mm of filter 2, can be included. These individual segment lengths can be appropriately changed according to suitability for manufacturing, quality requirements, and the like. In a non-illustrated variant, the aerosol generating segment 1 is shortened and a front (or upstream) functional segment is provided such as described in EP4183272. The functional element may act to prevent falling of the aerosol generating substrate (e.g., tobacco filler) from the upstream end of the article. The functional element can advantageously be made of a filter as defined in the present invention. The length of the functional element may be comprised between 5 and 15 mm.

[0185] The tobacco substrate of the smoking or aerosol generating article of the invention may comprise leaf tobacco, tobacco lamina, tobacco stems, paper reconstituted tobacco (RTB), cast tobacco, extruded tobacco, laminated tobacco, expanded tobacco (ETB), cut rolled expanded stems (CRES), tobacco liquid, tobacco extract and combinations thereof. The tobacco or plant substrate may be formed as gathered sheet, shreds, fragments, pellets, strips, beads, powder and blends or combinations thereof. The tobacco may be selected amongst different types and grades. Types of tobacco may be selected amongst Virginia, Burley, Oriental or others. Tobacco leaf may be treated by flue curing, air curing, sun curing. The combinations or blend maybe selected so as to control nicotine blend to a desired level, e.g., between 1 wt. % and 3 wt.%. The blend may be typical Virginia or American blends or others more specifically designed for heat-not-burn vaping. The tobacco substrate may contain aerosol former. The aerosol former may comprise glycerol, propylene glycol (PG), triethyl citrate (TEC), triacetin, and 1,3-butadeniol or combinations thereof. The amount of aerosol may be comprised between 4 wt.% and 30 wt.% in dry basis of the tobacco substrate. The tobacco substrate may further comprise volatiles flavor components, e.g., in liquid, solid or gel form (e.g., ethyl vanillin, guaiacol, menthol, peppermint oil, etc.).

Claims

CLAIMS1. A bale of nonwoven material, comprising: a continuous sheet of nonwoven material folded into a plurality of layers (431, 432, 433, 434, 435) stacked onto each other in a first direction (V), wherein folding edges of the individual layers of the plurality of layers are located on a first side of the bale and on a second side of the bale opposite to the first side, wherein on at least one of the first and second sides, a first layer (431) of the plurality of layers (431, 432, 433, 434, 435) is positioned on a second layer (432) of the plurality of layers such that a folding edge of the first layer (431) is positioned at a first distance (a) to a folding edge of the second layer (432) in a second direction (H’) substantially perpendicular to the first direction.

2. The bale according to the preceding claim, wherein a third layer (433) of the plurality of layers (431, 432, 433, 434, 435) is positioned on the second layer (432), such that an folding edge of the third layer (433) is positioned at a second distance (b) to the folding edge of the second layer (432) in the second direction (H’), wherein the second distance (b) is preferably substantially similar to the first distance (a).

3. The bale according to the preceding claim, wherein a fourth layer (434) of the plurality of layers (431, 432, 433, 434, 435) is positioned on the third layer (433), such that a folding edge of the fourth layer (434) is positioned at a third distance (c) to the folding edge of the third layer (433) in the second direction (H’), and the folding edge of the fourth layer (434) is preferably positioned substantially above the folding edge of the second layer (432) in the first direction V, and / or the third distance (c) is preferably substantially similar to the first distance (a).

4. The bale according to the preceding claim, wherein a fifth layer (435) of the plurality of layers (431, 432, 433, 434, 435) is positioned on the fourth layer (434), such that a folding edge of the fifth layer (435) is positioned at a fourth distance (d) to the folding edge of the fourth layer (434) in the second direction (H’), andthe folding edge of the fifth layer (435) is preferably positioned substantially above the folding edge of the first layer (431) in the first direction V, and / or the fourth distance (d) is preferably substantially similar to the first distance (a).

5. The bale according to any one of the preceding claims, wherein an nthlayer of the plurality of layers (431, 432, 433, 434, 435) is positioned on the n-ithlayer, such that a folding edge of the nthlayer is positioned at an mthdistance (m) to the folding edge of the n-ithlayer in the second direction (H’), wherein n is an integer of at least 7, and the folding edge of the nthlayer is preferably positioned substantially above the folding edge of the n-2thlayer, above the folding edge of the n-3thlayer, above the folding edge of the n-4thlayer or above the folding edge of the n-5thlayer in the first direction V, and / or the mthdistance (m) is preferably substantially similar to the first distance (a).

6. The bale according to any one of the preceding claims, wherein the folding edges of the plurality of layers (431, 432, 433, 434, 435) are arranged in predetermined pattern, preferably having a zigzag-shape, on at least one side of the bale, wherein the predetermined pattern, preferably having a zigzag-shape, is formed by at least two individual layers of the plurality of layers (431, 432, 433, 434, 435), preferably by at least three individual layers (431, 432, 433) of the plurality of layers (431, 432, 433? 434? 435)? more preferably by five individual layers (431, 432, 433, 434, 435) of the plurality of layers (431, 432, 433, 434, 435).

7. The bale according to any one of the preceding claims, wherein the first distance (a) is at least 1 mm, preferably at least 2 mm, more preferably at least 5 mm, even more preferably at least 7.5 mm, and most preferably at least 10 mm; and / or wherein the first distance (a) is at most 20 mm, preferably at most 17.5 mm, more preferably at most 15 mm, even more preferably at most 12.5 mm, and most preferably at most 100mm.

8. The bale according to any one of the preceding claims, wherein the individual layers of the one or more layers (431, 432, 433, 434, 435) are formed by two sheet portions (431a, 431b) of the continuous sheet of nonwoven, the sheet portions (431a, 43ab) being formed by folding the continuous sheet of nonwoven material at thefolding edge (440), wherein the two sheet portions (431a, 431b) are connected to each other via the folding edge (440).

9. A method for manufacturing a bale of nonwoven material comprising the steps of: folding a continuous sheet of nonwoven material into a plurality of layers stacked onto each other in a first direction (V) on a surface, preferably on a pallet, such that folding edges of the individual layers of the plurality of layers are located on a first side of the bale and on a second side of the bale opposite to the first side, wherein folding the continuous sheet of nonwoven material further comprises folding at least a first layer (431) and a second layer (432), wherein on at least one of the first and second sides of the bale, the first layer (431) is positioned on the second layer (432) such that a folding edge of the first layer (431) is positioned at a first distance (a) to a folding edge of the second layer (432) in a second direction (H’) substantially perpendicular to the first direction.

10. The method according to the preceding claim, wherein folding the continuous sheet of nonwoven material further comprises: folding a third layer (433), wherein the third layer (433) is positioned on the second layer (432), such that an folding edge of the third layer (433) is positioned at a second distance (b) to the folding edge of the second layer (432) in the second direction (H’), wherein preferably the second distance (b) is substantially similar to the first distance (a).

11. The method according to the preceding claim, wherein folding the continuous sheet of nonwoven material further comprises: folding a fourth layer (434), wherein the fourth layer (434) is positioned on the third layer (433), such that a folding edge of the fourth layer (434) is positioned at a third distance (c) to the folding edge of the third layer (433) in the second direction (H’), and the folding edge of the fourth layer (434) is preferably positioned substantially above the folding edge of the second layer (432) in the first direction V, and / or the third distance (c) is preferably substantially similar to the first distance (a).

12. The method according to the preceding claim, wherein folding the continuous sheet of nonwoven material further comprises: folding a fifth layer (435), wherein the fifth layer (435) is positioned on the fourth layer (434), such that a folding edge of the fifth layer (435) is positioned at a fourth distance (d) to the folding edge of the fourth layer (434) in the second direction (H’), and the folding edge of the fifth layer (435) is preferably positioned substantially above the folding edge of the first layer (431) in the first direction V, and / or the fourth distance (d) is preferably substantially similar to the first distance (a).

13. The method according to any one of claims 8 to 12, wherein folding the continuous sheet of nonwoven material further comprises: folding an nthlayer, wherein the nthlayer of the plurality of layers (431, 432, 433, 434, 435) is positioned on the n-ithlayer, such that a folding edge of the nthlayer is positioned at an mthdistance (m) to the folding edge of the n-ithlayer in the second direction (H’), wherein n is an integer of at least 7, and the folding edge of the nthlayer is preferably positioned substantially above the folding edge of the n-2thlayer, above the folding edge of the n-3thlayer, above the folding edge of the n-4thlayer or above the folding edge of the n-5thlayer in the first direction V, and / or the mthdistance (m) is preferably substantially similar to the first distance (a).

14. The method according to any one of claims 8 to 13, wherein folding the continuous sheet of nonwoven material further comprises: arranging the edges of the plurality of layers (431, 432, 433, 434, 435) in a zigzag-shape on at least one side of the bale, wherein the zigzag-shape is formed by at least two individual layers of the plurality of layers (431, 432, 433, 434, 435), preferably by five individual layers (431, 432, 433, 434, 435) of the plurality of layers (431, 432, 433, 434, 435)-15. A method for manufacturing a filter comprising nonwoven material for being used in an aerosol generating article, the method comprising:obtaining a nonwoven material from a bale according to any one of claims 1 to 7, and crimping the nonwoven material to obtain the filter.

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