Aerosol-generating article with hollow support element

Abstract

An aerosol-generating article (10) for generating an inhalable aerosol upon heating, the aerosol-generating article comprising: a strip (12) of an aerosol-generating substrate; a support element (22) (122) downstream of the strip (12) of aerosol-generating substrate, the support element (22) (122) comprising a first hollow tubular element (26) (126) providing one or more unrestricted flow channels defining a hollow interior region (28) (120), wherein the cross-sectional area of the hollow inner region (28) (120) is at least 80% of the total cross-sectional area of the first hollow tubular element (26) (126); and an aerosol cooling element (24) downstream of the support element (22), the aerosol cooling element (24) comprising a second hollow tubular element (34) and a gathering sheet (35) of material within the second hollow tubular element (34), the gathering sheet (35) defining a plurality of longitudinal flow channels.

Description

[0001] The present invention relates to an aerosol-generating article comprising an aerosol- generating substrate and adapted to generate an inhalable aerosol upon heating.

[0002] Aerosol-generating articles in which a tobacco-containing substrate is heated rather than combusted are known in the art. Typically, in such heated smoking articles, an aerosol is generated by the transfer of heat from a heat source to a physically separate aerosol- generating substrate or material, which can be positioned in contact with, inside, around or downstream of the heat source. During use of the aerosol-generating article, volatile compounds are released from the aerosol-generating substrate by heat transfer from the heat source and are entrained in air drawn through the aerosol-generating article. As the released compounds cool, they condense to form an aerosol.

[0003] Many prior art documents disclose aerosol-generating devices for consuming aerosol- generating articles. Such devices include, for example, electrically heated aerosol- generating devices in which an aerosol is generated by the transfer of heat from one or more electric heater elements of the aerosol-generating device to an aerosol-generating substrate of a heated aerosol-generating article. For example, electrically heated aerosol- generating devices comprising an internal heater blade adapted to be inserted into an aerosol-generating substrate have been proposed. It is also known to use aerosol-generating articles in combination with external heating systems. For example, WO 2020 / 115151 describes the provision of one or more heating elements arranged around the periphery of an aerosol-generating article when the aerosol-generating article is received in a cavity of an aerosol-generating device. As an alternative, inductively heatable aerosol-generating articles are proposed by WO 2015 / 176898, which comprise an aerosol-generating substrate and a susceptor arranged within the aerosol-generating substrate.

[0004] Aerosol-generating articles in which a tobacco-containing substrate is heated rather than combusted present a number of challenges that are not encountered with conventional smoking articles. Firstly, the tobacco-containing substrate is typically heated to a significantly lower temperature than the temperature reached by the combustion front in a conventional cigarette. This can affect the release of nicotine from the tobacco-containing substrate and the delivery of nicotine to the consumer. At the same time, if the heating temperature is increased in an attempt to enhance nicotine delivery, the generated aerosol typically needs to cool to a greater extent and more rapidly before it reaches the consumer. However, technical solutions typically used to cool mainstream smoke in conventional smoking articles, such as the provision of a high filtration efficiency segment at the mouth end of a cigarette, can have undesirable effects in aerosol-generating articles in which a tobacco-containing substrate is heated rather than combusted, as they can reduce the delivery of nicotine. It is therefore desirable to provide new aerosol-generating articles that are able to consistently ensure the provision of a satisfactory aerosol delivery to the consumer.

[0005] Furthermore, there is a generally recognized need for aerosol-generating articles that are easy to use and have improved utility. For example, it would be desirable to provide an aerosol-generating article that can be easily inserted into the heating chamber of an aerosol-generating device, and at the same time can be securely retained within the heating chamber so that it does not slip out during use.

[0006] It would also be desirable to provide an aerosol-generating article that can be produced using more sustainable materials in order to minimize the environmental impact of the used article.

[0007] The present disclosure relates to an aerosol-generating article. The aerosol-generating article may include a strip of aerosol-generating substrate. The aerosol-generating article may further include a support element downstream of the strip of aerosol-generating substrate. The support element may include a first hollow tubular element providing one or more unrestricted flow channels defining a hollow interior region. The cross-sectional area of ​​the hollow interior region may be at least 80% of the total cross-sectional area of ​​the first hollow tubular element. The aerosol-generating article may further include an aerosol-cooling element downstream of the support element. The aerosol-cooling element may include a second hollow tubular element. The aerosol-cooling element may further include a gathered sheet of material within the second hollow tubular element, the gathered sheet defining a plurality of longitudinal airflow channels.

[0008] According to the present invention, there is provided an aerosol-generating article for generating an inhalable aerosol upon heating, the aerosol-generating article comprising: a strip of an aerosol-generating substrate; a support element downstream of the strip of aerosol-generating substrate, the support element comprising a first hollow tubular element, the first hollow tubular element providing one or more unrestricted flow channels defining a hollow interior region, wherein the cross-sectional area of ​​the hollow interior region is at least 80% of the total cross-sectional area of ​​the first hollow tubular element; and an aerosol-cooling element downstream of the support element, the aerosol-cooling element comprising a second hollow tubular element and a gathered sheet of material within the second hollow tubular element, the gathered sheet defining a plurality of longitudinal flow channels.

[0009] According to the present invention, there is provided an aerosol-generating article for generating an inhalable aerosol upon heating, the aerosol-generating article comprising: a strip of an aerosol-generating substrate; a support element downstream of the strip of aerosol-generating substrate, the support element comprising a first hollow tubular element, the first hollow tubular element providing one or more unrestricted flow channels defining a hollow interior region, wherein the cross-sectional area of ​​the hollow interior region is at least 80% of the total cross-sectional area of ​​the first hollow tubular element; and an aerosol-cooling element defining one or more longitudinal airflow channels and having a total internal surface area of ​​at least 300 square millimeters.

[0010] As used herein, the term "aerosol-generating article" refers to an article comprising an aerosol-generating substrate that is heated to generate an inhalable aerosol and delivers the inhalable aerosol to a consumer. As used herein, the term "aerosol-generating substrate" means a substrate that is capable of releasing volatile compounds upon heating to generate an aerosol.

[0011] As used herein, the term "aerosol-generating device" refers to a device comprising a heater element that interacts with an aerosol-generating substrate of an aerosol-generating article to generate an aerosol.

[0012] As used herein with reference to the present invention, the term "rod" is intended to mean a generally elongated element, preferably a cylindrical element, of substantially circular, oval or elliptical cross-section.

[0013] As used herein, the term "hollow tubular element" refers to a generally elongated element that defines a lumen or airflow passageway along its longitudinal axis. The "inner diameter" of the hollow tubular element corresponds to the diameter of the airflow passageway.

[0014] In the context of the present invention, each hollow tubular element provides an unrestricted flow path. This means that the hollow tubular element provides a negligible level of resistance to suction (RTD). The term "negligible level of RTD" is used to describe a hollow tubular element having an RTD of less than 1 mm H2O / 10 mm length, preferably less than 0.4 mm H2O / 10 mm length, and more preferably less than 0.1 mm H2O / 10 mm length.

[0015] Unless otherwise stated, the resistance to draw (RTD) of a component or aerosol-generating article is measured in accordance with ISO 6565-2015. RTD refers to the pressure required to force air through the full length of the component. The term "pressure drop" or "draw resistance" of a component or article may also refer to "resistance to draw". Such terms generally refer to measurements in accordance with ISO 6565-2015. Typically, in the test, a volume flow rate of 17.5 ml / s is measured at the output or downstream end of the measuring component at a temperature of 22 degrees Celsius, a pressure of 101 kPa (about 760 torr) and a relative humidity of 60%. The conditions for smoking and the specifications for smoking machines are set forth in ISO Standard 3308 (ISO 3308:2000). The atmosphere for conditioning and testing is set forth in ISO Standard 3402 (ISO3402:1999).

[0016] As used herein, the term "longitudinal" refers to a direction corresponding to the principal longitudinal axis of an aerosol-generating article, which direction extends between the upstream and downstream ends of the aerosol-generating article.

[0017] The term "length" refers to the dimension of a component of an aerosol-generating article in the longitudinal direction. For example, it may be used to refer to the dimension of a strip or downstream section in the longitudinal direction.

[0018] As used herein, the terms "upstream" and "downstream" describe the relative position of an element or part of an element of an aerosol-generating article with respect to the direction in which aerosol is transported through the aerosol-generating article during use.

[0019] During use, air is drawn through the aerosol-generating article in a longitudinal direction. The term "transverse" refers to a direction perpendicular to the longitudinal axis. Unless otherwise specified, any reference to a "cross-section" of an aerosol-generating article or a component of an aerosol-generating article refers to a cross-section. The term "cross-sectional area" refers to the area of ​​a section taken transversely through a component of the aerosol-generating article, such as the first hollow tubular element.

[0020] As used herein, the term "hollow interior region" refers to the empty space within the first hollow tubular element. Where the first hollow tubular element contains more than one individual empty space, the "hollow interior region" refers to the combination of all of the empty spaces. Thus, the cross-sectional area of ​​the hollow interior region refers to the total area within the cross section of the first hollow tubular element occupied by the empty spaces. The total cross-sectional area of ​​the first hollow tubular element refers to the total area of ​​the cross section including any empty spaces.

[0021] In the aerosol-generating article of the present invention, the first hollow tubular element forming the support element is adapted such that the cross-sectional area of ​​the hollow interior region occupies at least 80% of the total cross-sectional area of ​​the first hollow tubular element. Thus, the hollow interior region within the support element is relatively large, and the support element has a relatively high proportion of empty space. As discussed in more detail below, this is preferably provided by a relatively large inner diameter.

[0022] Maximizing the hollow interior area of ​​the support element enables the cross-sectional area of ​​the hollow interior area to be adapted so that it is similar to or substantially the same as the cross-sectional area occupied by the gathered sheet material of the cooling element. This enables the aerosol to pass through a larger proportion of the cross-sectional area of ​​the aerosol-cooling element, which provides several technical benefits as described below.

[0023] Firstly, spreading the aerosol over a larger proportion of the cross-sectional area reduces the risk of melting the gathering sheet in the central portion of the aerosol-cooling element. This may be particularly important for embodiments in which the gathering sheet is formed from a polymeric material that may have a relatively low melting point. This may also be important for embodiments in which the length of the support element is relatively short, as less cooling of the aerosol will occur in the support element before the aerosol reaches the aerosol-cooling element.

[0024] Second, since a larger surface area of ​​the gathering sheet is available, the spreading of the aerosol over a larger proportion of the cross-sectional area provides for more efficient cooling of the aerosol.

[0025] For similar reasons, aerosol-cooling elements may provide more effective filtration of aerosols, for example to filter out undesirable aerosol compounds such as phenol.

[0026] These effects as described above are particularly important for preferred embodiments of the invention described below in which the aerosol-generating article is substantially non-ventilated along the support element and the aerosol-cooling element.

[0027] The relatively large hollow interior area of ​​the support element also means that cooling efficiency within the support element will be improved. Furthermore, to provide a relatively large hollow interior area within the first hollow tubular element, the wall thickness of the first hollow tubular element will typically be relatively thin. This will provide improved heat transfer from the interior to the exterior of the support element, thereby improving cooling efficiency within the support element. Thus, the specific configuration of the support element can provide improved cooling functionality even before the aerosol reaches the aerosol-cooling element.

[0028] Providing a support element with a relatively thin wall thickness also enables it to be formed from a potentially wider range of materials. In particular, the support element may be formed from paper or cardboard, both of which are lighter and more sustainable than more conventional materials used in aerosol-generating articles (e.g. cellulose acetate).

[0029] As defined above, the aerosol-generating article of the present invention comprises a support element downstream of the strip of aerosol-generating substrate. Preferably, the upstream end of the support element abuts the downstream end of the strip of aerosol-generating substrate. Preferably, the downstream end of the support element abuts the upstream end of the aerosol-cooling element.

[0030] The support element comprises a first hollow tubular element.Preferably, the support element comprises only the first hollow tubular element.

[0031] As described above, the first hollow tubular element is adapted to provide a hollow interior region having a cross-sectional area of ​​at least 80%, more preferably at least 85%, and more preferably at least 90% of the total cross-sectional area of ​​the first hollow tubular element.

[0032] Where at least one of the cross-sectional area of ​​the hollow interior region and the total cross-sectional area varies along the length of the first hollow tubular element, the average ratio of the cross-sectional area of ​​the hollow interior region to the total cross-sectional area along the entire length should be at least 80%.

[0033] The hollow interior region may be provided as a single empty flow channel within the first hollow tubular element, or as groups of flow channels.

[0034] Preferably, the first hollow tubular element comprises a peripheral wall defining a single unrestricted flow channel, said flow channel corresponding to the hollow interior region. In such embodiments, the first hollow tubular element thus has a simple tubular structure. The diameter of the flow channel corresponds to the inner diameter (D1) of the first hollow tubular element.

[0035] Preferably, the inner diameter of the first hollow tubular element of the supporting element is at least 6 mm, more preferably at least 6.1 mm, more preferably at least 6.2 mm, more preferably at least 6.3 mm, more preferably at least 6.4 mm, more preferably at least 6.5 mm, more preferably at least 6.6 mm, more preferably at least 6.7 mm, more preferably at least 6.8 mm.

[0036] The inner diameter of the first hollow tubular element is preferably less than 7.3 mm, more preferably less than 7.25 mm, more preferably less than 7.2 mm, more preferably less than 7.15 mm, more preferably less than 7.1 mm, more preferably less than 7 mm.

[0037] Thus, the inner diameter of the first hollow tubular element may be between 6 mm and 7.3 mm, or between 6.1 mm and 7.25 mm, or between 6.2 mm and 7.2 mm, or between 6.3 mm and 7.2 mm, or between 6.4 mm and 7.15 mm, or between 6.5 mm and 7.15 mm, or between 6.6 mm and 7.1 mm, or between 6.7 mm and 7.1 mm, or between 6.8 mm and 7 mm.

[0038] Preferably, the first hollow tubular element has a constant inner diameter along its entire length. However, the inner diameter of the first hollow tubular element may vary along its length. In such cases, the "inner diameter" as referred to herein should be considered to be the average inner diameter over the length of the hollow tubular element.

[0039] The outer diameter of the first hollow tubular element is preferably between 5 mm and 12 mm, more preferably between 6 mm and 10 mm, more preferably between 7 mm and 8 mm, and more preferably between 7 mm and 7.5 mm. In some embodiments, the outer diameter of the first hollow tubular element can be less than 7 mm, for example, between 5 mm and 7 mm, or between 6 mm and 7 mm.

[0040] Preferably, the first hollow tubular element has an outer diameter substantially equal to the outer diameter of the rod of aerosol-generating substrate and substantially equal to the outer diameter of the aerosol-generating article.

[0041] The ratio of the inner diameter of the first hollow tubular element to the outer diameter of the first hollow tubular element is preferably at least 0.75, more preferably at least 0.8, more preferably at least 0.85, more preferably at least 0.9. The ratio of the inner diameter of the first hollow tubular element to the outer diameter of the first hollow tubular element may be as high as 0.98.

[0042] The lumen of the first hollow tubular element may have any cross-sectional shape. Preferably, the lumen of the first hollow tubular element has a circular or substantially circular cross-sectional shape.

[0043] The peripheral wall of the first hollow tubular element preferably has a wall thickness of less than 0.5 mm, more preferably less than 0.45 mm, more preferably less than 0.4 mm, more preferably less than 0.35 mm. The wall thickness is preferably at least 0.1 mm, more preferably at least 0.15 mm, more preferably at least 0.2 mm.

[0044] For example, the wall thickness of the first hollow tubular element may be between 0.1 mm and 0.5 mm, or between 0.15 mm and 0.45 mm, or between 0.15 mm and 0.4 mm, or between 0.2 mm and 0.4 mm, or between 0.2 mm and 0.35 mm. As mentioned above, the first hollow tubular element thus has a relatively thin wall.

[0045] The first hollow tubular element is preferably formed from a paper-based material, such as paper or cardboard. Preferably, the first hollow tubular element is a paper tube formed from one or more paper layers. More preferably, the first hollow tubular element is a paper tube formed from a plurality of overlapping paper layers.

[0046] The first hollow tubular element preferably comprises at least two overlapping paper layers, more preferably at least three overlapping paper layers. The first hollow tubular element preferably comprises up to ten overlapping paper layers, more preferably up to five overlapping paper layers. For example, the first hollow tubular element may comprise from two to ten overlapping paper layers, or from three to five overlapping paper layers. The paper layers may be formed from the same paper material or from different paper materials.

[0047] Each paper layer will typically extend at least one turn around the first hollow tubular element, and preferably each paper layer will extend multiple turns around the first hollow tubular element to build up the structure of the wall and achieve the desired wall thickness.

[0048] Preferably, the multiple overlapping paper layers are helically wound around the longitudinal axis of the first hollow tubular element. This provides a spirally wound structure similar to the layered structure of conventional paper straws. Hollow tubular elements including the helical arrangement of layers used in the present invention can be manufactured using existing straw manufacturing equipment, such as the Hauni StrawMaker (HSM) from Hauni Maschinenbau GmbH.

[0049] The use of a spirally wound structure provides the first hollow tubular element with optimal structural strength, with increased mechanical strength and stiffness in all directions, compared to a similar structure having simple longitudinal wrapping. This increased strength and stiffness enables the support element to perform its intended function of resisting downstream movement of the aerosol-generating substrate, for example, during insertion of a heating element of an aerosol-generating device. This increased stiffness is particularly advantageous given the reduced wall thickness of the first hollow tubular element.

[0050] The individual paper layers of the paper tube preferably each have a thickness of between 30 and 200 microns, more preferably between 45 and 150 microns, more preferably between 45 and 135 microns, more preferably between 75 and 125 microns.

[0051] The individual paper layers forming the paper tube may have the same thickness as one another. Alternatively, the individual paper layers forming the paper tube may have different thicknesses. For example, the paper tube may be formed from multiple paper layers, each having a thickness within the above-defined range, but wherein the thickness of the paper layers decreases from the inner layer to the outer layer. This arrangement may be beneficial during the manufacturing process because thicker paper layers require greater force to bend them into shape, and it is easier to apply greater force to one or more inner layers during manufacturing (e.g., by wrapping the layers around a mandrel).

[0052] For example, the paper tube forming the first hollow tubular element may include one or more layers of a first paper material and one or more layers of a second paper material, wherein the thickness of the second paper material is greater than the thickness of the first paper material. The thickness of the second paper material may be at least 25 microns greater than the thickness of the first paper material, or at least 30 microns greater, or at least 40 microns greater.

[0053] The individual paper layers of the paper tube preferably each have a grammage of between 25 grams per square meter (gsm) and 150 gsm, or between 30 gsm and 130 gsm, or between 35 gsm and 120 gsm.

[0054] The individual paper layers forming the paper tube may have the same grammage as one another. Alternatively, the individual paper layers forming the paper tube may have different grammages. For example, the paper tube may be formed from a plurality of paper layers, each having a grammage within the above-defined range, but wherein the grammage of the paper layers decreases from the inner layer to the outer layer.

[0055] For example, the paper tube forming the first hollow tubular element may include one or more layers of a first paper material and one or more layers of a second paper material, wherein the grammage of the second paper material is greater than the grammage of the first paper material. The grammage of the second paper material may be at least 25 gsm greater, or at least 30 gsm greater, or at least 40 gsm greater than the thickness of the first paper material.

[0056] The paper tube may be formed of paper layers having the same composition as each other. Alternatively, the paper tube may be formed of paper layers having different compositions from each other.

[0057] Preferably, the paper tube comprises at least one hydrophobic paper layer. The hydrophobic paper layer is preferably arranged as the innermost layer of the paper tube so that it provides the inner surface of the paper tube.

[0058] The term "hydrophobic" refers to a surface that exhibits water-repellent properties. A useful method for determining this is to measure the water contact angle. The "water contact angle" is the angle, conventionally measured, across a liquid when a liquid / vapor interface encounters a solid surface. It quantifies the wettability of a solid surface by a liquid via Young's equation. Hydrophobicity, or the water contact angle, can be measured using the TAPPI T558 test method, with the results presented as the interfacial contact angle and reported in degrees, and can range from approximately zero to approximately 180 degrees.

[0059] In a preferred embodiment, the hydrophobic paper layer is a paper layer comprising a paper layer having a water contact angle of about 30 degrees or greater, and preferably about 35 degrees or greater, or about 40 degrees or greater, or about 45 degrees or greater.

[0060] For example, the hydrophobic paper layer may comprise PVOH (polyvinyl alcohol), silicon, or a wax such as paraffin. The hydrophobic paper layer may have a hydrophobic coating of one of these materials applied to its surface, or the surface of the paper layer may have been surface treated with one of these materials to provide hydrophobicity.

[0061] Providing a hydrophobic layer inside the paper tube prevents moisture from the aerosol from penetrating the paper tube, making it possible to maintain the structural rigidity of the support element during use. It can also advantageously reduce friction with the surface of manufacturing equipment (such as a mandrel) during manufacturing.

[0062] In an alternative preferred embodiment of the present invention, the first hollow tubular element may include a peripheral wall defining a hollow interior region (as described above with respect to other preferred embodiments formed using simple tubular elements), and further include one or more internal protrusions extending from the peripheral wall into the hollow interior region. In such an embodiment, the first hollow tubular element thus has a more complex internal structure, wherein the one or more internal protrusions provide additional strength and rigidity to the support element. The peripheral wall may be formed from a tube, such as a paper tube.

[0063] Each internal protrusion extends from a first point on the inner surface of the peripheral wall of the first hollow tubular element. Each internal protrusion may extend across the hollow interior region defined by the peripheral wall to a second point within the hollow interior region. Alternatively, each internal protrusion may extend to a second point on the inner surface of the peripheral wall of the first hollow tubular element.

[0064] The one or more internal protrusions can be formed from a sheet of material. The one or more internal protrusions can be integrally formed with the peripheral wall. Alternatively, the one or more support elements can be distinct from the peripheral wall. In such embodiments, the one or more internal protrusions can be attached to the inner surface of the peripheral wall of the first hollow tubular element with the aid of a suitable adhesive.

[0065] Each internal protrusion can extend along about 10% to about 100% of the length of the first hollow tubular element, preferably along about 25% to about 100% of the length of the first hollow tubular element, and more preferably along about 50% to about 100% of the length of the first hollow tubular element. Most preferably, each internal protrusion extends along substantially the entire length of the first hollow tubular element. Thus, the internal protrusion can have a length approximately equal to the length of the hollow tubular element. This can provide the first hollow tubular element with additional mechanical strength and rigidity along the entire length of the hollow tubular element.

[0066] Each internal projection may depend from the peripheral wall along a first fold line of the sheet of material forming the internal projection, wherein the first fold line is located at a first point at the peripheral wall. Advantageously, this may simplify manufacture of the first hollow tubular element.

[0067] The one or more internal protrusions may divide the hollow interior region of the first hollow tubular element into a plurality of channels. The number of channels may be selected based on the desired nucleation of aerosol particles and the desired resistance to inhalation of the aerosol-generating article. The one or more internal protrusions may divide the lumen of the first hollow tubular element into two channels. The one or more internal protrusions may divide the lumen of the first hollow tubular element into three channels. The one or more internal protrusions may divide the lumen of the first hollow tubular element into four channels. The one or more internal protrusions may divide the lumen of the first hollow tubular element into two to four channels. The one or more internal protrusions may divide the lumen of the first hollow tubular element into at least three channels.

[0068] The first hollow tubular element may include a single internal protrusion. Alternatively, the first hollow tubular element may include two to six internal protrusions. Preferably, the hollow tubular element includes three internal protrusions. The three internal protrusions may help improve the resistance of the first hollow tubular element to collapse or deformation.

[0069] Each of the one or more internal protrusions may be identical to one another. This may simplify the manufacture of the first hollow tubular element. Alternatively, one of the internal protrusions may be different from another internal protrusion.

[0070] Further details of suitable hollow tubular elements comprising one or more internal protrusions may be found in WO-A-2022 / 129600.

[0071] The support element may have a length between 5 mm and 15 mm. Preferably, the support element has a length of at least about 6 mm, more preferably at least about 7 mm. Preferably, the support element has a length of less than about 12 mm, more preferably less than about 10 mm.

[0072] In some embodiments, the support element has a length of about 5 mm to about 15 mm, preferably about 6 mm to about 15 mm, and more preferably about 7 mm to about 15 mm. In other embodiments, the support element has a length of about 5 mm to about 12 mm, preferably about 6 mm to about 12 mm, and more preferably about 7 mm to about 12 mm. In still other embodiments, the support element has a length of about 5 mm to about 10 mm, preferably about 6 mm to about 10 mm, and more preferably about 7 mm to about 10 mm. In particularly preferred embodiments of the present invention, the support element has a length of 8 mm or 9 mm.

[0073] In a preferred embodiment, wherein the supporting element consists of a first hollow tubular element, the length of the first hollow tubular element is within the range defined above.

[0074] Therefore, the first hollow tubular element preferably has a length between 5 mm and 15 mm. Preferably, the first hollow tubular element has a length of at least 6 mm, more preferably at least 7 mm. Preferably, the first hollow tubular element has a length of less than 12 mm, more preferably less than 10 mm. In a particularly preferred embodiment of the present invention, the first hollow tubular element has a length of 8 mm or 9 mm.

[0075] Preferably, the ratio of the length of the support element to the overall length of the aerosol-generating article is at least 0.13, more preferably at least 0.14, even more preferably at least 0.15. The ratio of the length of the support element to the overall length of the aerosol-generating article is preferably less than 0.3, more preferably less than 0.25, even more preferably less than 0.20.

[0076] In some embodiments, the ratio of the length of the support element to the overall length of the aerosol-generating article is preferably from 0.13 to 0.3, more preferably from 0.14 to 0.3, and even more preferably from 0.15 to 0.3. In other embodiments, the ratio of the length of the support element to the overall length of the aerosol-generating article is preferably from 0.13 to 0.25, more preferably from 0.14 to 0.25, and even more preferably from 0.15 to 0.25. In further embodiments, the ratio of the length of the support element to the overall length of the aerosol-generating article is preferably from 0.13 to 0.2, more preferably from 0.14 to 0.2, and even more preferably from 0.15 to 0.2. In particularly preferred embodiments, the ratio of the length of the support element to the overall length of the aerosol-generating article is about 0.18.

[0077] Preferably, the support element has a negligible level of RTD. For example, preferably, the support element has an RTD of less than 2 mmH2O, more preferably less than 1.5 mmH2O, more preferably less than 1 mmH2O, more preferably less than 0.5 mmH2O, and most preferably about 0 mmH2O.

[0078] As defined above, in the aerosol-generating article of the present invention, the aerosol-cooling element is disposed downstream of the support element. Preferably, the upstream end of the aerosol-cooling element abuts the downstream end of the support element. The downstream end of the aerosol-cooling element may coincide with the downstream end of the aerosol-generating article. Alternatively, the aerosol-generating article may include one or more additional components, as described below, downstream of the aerosol-cooling element.

[0079] The aerosol-cooling element includes a second hollow tubular element and a plurality of longitudinally extending airflow channels. The plurality of longitudinally extending airflow channels may be defined by sheet material that has been gathered to form the channels. The plurality of longitudinally extending airflow channels may be defined by a single sheet that has been gathered to form the plurality of channels. Alternatively, the plurality of longitudinally extending airflow channels may be defined by a plurality of sheets that have been gathered to form the plurality of channels.

[0080] In some embodiments, the aerosol-cooling element may comprise a gathered sheet of material selected from metal foil, polymeric material, and substantially non-porous paper or cardboard. In some embodiments, the aerosol-cooling element may comprise a gathered sheet of material selected from polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose acetate (CA), and aluminum foil.

[0081] Preferably, the aerosol-cooling element comprises a gathered sheet of polymeric material.

[0082] In a preferred embodiment the aerosol-cooling element comprises a gathered sheet of biodegradable material. For example, a gathered sheet of non-porous paper or a gathered sheet of biodegradable polymeric material such as polylactic acid or grades (a family of commercially available starch-based copolyesters).

[0083] In particularly preferred embodiments, the aerosol-cooling element comprises a gathered sheet of polylactic acid.

[0084] The aerosol-cooling element may be formed from a gathered sheet of material having a specific surface area between 10 mm2 / mg weight and 100 mm2 / mg weight. In some embodiments, the aerosol-cooling element may be formed from a gathered sheet of material having a specific surface area of ​​approximately 35 mm2 / mg.

[0085] The aerosol-cooling element can have a total surface area of between 300 square millimetres per millimetre length to about 1000 square millimetres per millimetre length. In preferred embodiments, the aerosol-cooling element has a total surface area of about 500 square millimetres per millimetre length.

[0086] Preferably, the aerosol-cooling element has a low draw resistance. That is, preferably, the aerosol-cooling element provides a low resistance to air passing through the aerosol-generating article. Preferably, the aerosol-cooling element does not substantially affect the draw resistance of the aerosol-generating article.

[0087] Preferably, the aerosol-cooling element has a porosity of between 50% and 90% in the longitudinal direction. The porosity of the aerosol-cooling element along the longitudinal direction is defined by the ratio of the cross-sectional area of the material forming the aerosol-cooling element to the internal cross-sectional area of the aerosol-generating article at the location of the aerosol-cooling element.

[0088] In some embodiments, the aerosol-cooling element removes a proportion of the water vapour content of an aerosol drawn through the aerosol-cooling element. In some embodiments, a proportion of other volatile substances can be removed from the aerosol stream as the aerosol is drawn through the aerosol-cooling element. For example, in some embodiments, a proportion of phenolic compounds can be removed from the aerosol stream as the aerosol is drawn through the aerosol-cooling element.

[0089] The phenolic compounds can be removed by interaction with the material forming the aerosol-cooling element. For example, the aerosol-cooling element can be formed from a material that adsorbs phenolic compounds, such as phenol and cresol.

[0090] The phenolic compounds can be removed by interaction with water droplets condensed on the surface of the aerosol-cooling element.

[0091] As described above, the aerosol-cooling element comprises a second hollow tubular element comprising an aggregated sheet of material.

[0092] Preferably, the inner diameter of the second hollow tubular element is maximised so as to maximise the volume and cross-sectional area that can be occupied by the aggregated sheet of material.

[0093] Preferably, the second hollow tubular element of the aerosol-cooling element has an inner diameter D2 of at least 6 millimetres, more preferably at least 6.1 millimetres, more preferably at least 6.2 millimetres, more preferably at least 6.3 millimetres, more preferably at least 6.4 millimetres, more preferably at least 6.5 millimetres, more preferably at least 6.6 millimetres, more preferably at least 6.7 millimetres, more preferably at least 6.8 millimetres.

[0094] The inner diameter of the second hollow tubular element is preferably less than 7.3 mm, more preferably less than 7.25 mm, more preferably less than 7.2 mm, more preferably less than 7.15 mm, more preferably less than 7.1 mm, more preferably less than 7 mm.

[0095] Thus, the inner diameter of the second hollow tubular element may be between 6 mm and 7.3 mm, or between 6.1 mm and 7.25 mm, or between 6.2 mm and 7.2 mm, or between 6.3 mm and 7.2 mm, or between 6.4 mm and 7.15 mm, or between 6.5 mm and 7.15 mm, or between 6.6 mm and 7.1 mm, or between 6.7 mm and 7.1 mm, or between 6.8 mm and 7 mm.

[0096] Preferably, the second hollow tubular element has a constant inner diameter along its entire length. However, the inner diameter of the second hollow tubular element may vary along its length. In such cases, "inner diameter" as referred to herein should be considered to be the average inner diameter over the length of the hollow tubular element.

[0097] Preferably, the inner diameter of the second hollow tubular element is selected to be as close as possible to the inner diameter of the first hollow tubular element. This enables the cross-sectional area of ​​the inner hollow region of the support element to be similar to the cross-sectional area of ​​the gathering sheet in the aerosol-cooling element, so as to optimize contact of the aerosol with the gathering sheet across the entire cross-section of the aerosol-cooling element.

[0098] Preferably, the ratio between the inner diameter of the first hollow tubular element and the inner diameter of the second hollow tubular element is therefore at least 0.8, more preferably at least 0.85, more preferably at least 0.9, more preferably at least 0.95 and most preferably about 1. The ratio between the inner diameter of the first hollow tubular element and the inner diameter of the second hollow tubular element may be less than 1.25, more preferably less than 1.2, more preferably less than 1.15.

[0099] For example, the ratio between the inner diameter of the first hollow tubular element and the inner diameter of the second hollow tubular element can be between 0.8 and 1.25, or between 0.85 and 1.25, or between 0.9 and 1.25, or between 0.95 and 1.25, or between 0.8 and 1.2, or between 0.85 and 1.2, or between 0.9 and 1.2, or between 0.95 and 1.2, or between 0.8 and 1.15, or between 0.85 and 1.15, or between 0.9 and 1.15, or between 0.95 and 1.15. In a particularly preferred embodiment, the ratio between the inner diameter of the first hollow tubular element and the inner diameter of the second hollow tubular element is about 1.

[0100] The outer diameter of the second hollow tubular element is preferably between 5 and 12 millimetres, more preferably between 6 and 10 millimetres, more preferably between 7 and 8 millimetres, more preferably between 7 and 7.5 millimetres. In some embodiments, the outer diameter of the second hollow tubular element can be less than 7 millimetres, for example between 5 and 7 millimetres, or between 6 and 7 millimetres.

[0101] The second hollow tubular element preferably has an outer diameter that is substantially equal to the outer diameter of the rod of aerosol- generating substrate and the outer diameter of the aerosol-generating article.

[0102] The ratio of the inner diameter of the second hollow tubular element to the outer diameter of the second hollow tubular element is preferably at least 0.75, more preferably at least 0.8, more preferably at least 0.85, more preferably at least 0.9. The ratio between the inner diameter of the second hollow tubular element and the outer diameter of the second hollow tubular element can be up to 0.98.

[0103] The cavity of the second hollow tubular element can have any cross-sectional shape. Preferably, the cavity of the second hollow tubular element has a circular or substantially circular cross-sectional shape.

[0104] The wall thickness of the second hollow tubular element is preferably less than 0.5 millimetres, more preferably less than 0.45 millimetres, more preferably less than 0.4 millimetres, more preferably less than 0.35 millimetres. The wall thickness is preferably at least 0.1 millimetres, more preferably at least 0.15 millimetres, more preferably at least 0.2 millimetres.

[0105] For example, the wall thickness of the second hollow tubular element can be between 0.1 and 0.5 millimetres, or between 0.15 and 0.45 millimetres, or between 0.15 and 0.4 millimetres, or between 0.2 and 0.4 millimetres, or between 0.2 and 0.35 millimetres. As noted above, the second hollow tubular element thus has a relatively thin wall.

[0106] The second hollow tubular element is preferably formed from a paper-based material, such as paper or cardboard material. For example, the second hollow tubular element can be a paper tube. Any of the materials described above in relation to the first hollow tubular element are also suitable for forming the second hollow tubular element.

[0107] The aerosol-cooling element can have a length of between 10 and 25 millimetres. Preferably, the aerosol-cooling element has a length of at least 12 millimetres, more preferably at least 15 millimetres. Preferably, the aerosol-cooling element has a length of less than 22 millimetres, more preferably less than 20 millimetres.

[0108] In some embodiments, the aerosol-cooling element has a length of 10 to 25 millimetres, preferably 12 to 25 millimetres, more preferably 15 to 25 millimetres. In other embodiments, the aerosol-cooling element has a length of 10 to 22 millimetres, preferably 12 to 22 millimetres, more preferably 15 to 22 millimetres. In further embodiments, the aerosol-cooling element has a length of 10 to 20 millimetres, preferably 12 to 20 millimetres, more preferably 15 to 20 millimetres. In particularly preferred embodiments of the application, the aerosol-cooling element has a length of about 18 millimetres.

[0109] In preferred embodiments in which the aerosol-cooling element consists of a second hollow tubular element comprising the gathered sheet material, the second hollow tubular element has a length in the range defined above.

[0110] For example, in some embodiments, the second hollow tubular element has a length of 10 to 25 millimetres, preferably 12 to 25 millimetres, more preferably 15 to 25 millimetres. In other embodiments, the second hollow tubular element has a length of 10 to 22 millimetres, preferably 12 to 22 millimetres, more preferably 15 to 22 millimetres. In further embodiments, the second hollow tubular element has a length of 10 to 20 millimetres, preferably 12 to 20 millimetres, more preferably 15 to 20 millimetres. In particularly preferred embodiments of the application, the second hollow tubular element has a length of about 18 millimetres.

[0111] Preferably, the ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article substrate is at least 0.25, more preferably at least 0.3, even more preferably at least 0.35. The ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article substrate is preferably less than 0.55, more preferably less than 0.5, even more preferably less than 0.45.

[0112] In some embodiments, the ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article is preferably 0.25 to 0.55, more preferably 0.3 to 0.55, even more preferably 0.35 to 0.55. In other embodiments, the ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article is preferably 0.25 to 0.5, more preferably 0.3 to 0.5, even more preferably 0.35 to 0.5. In further embodiments, the ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article is preferably 0.25 to 0.45, more preferably 0.3 to 0.45, even more preferably 0.35 to 0.45. In particularly preferred embodiments, the ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article is about 0.4.

[0113] Preferably, the ratio between the length of the aerosol-cooling element and the length of the support element is at least 1.5, more preferably at least 1.6, more preferably at least 1.7, more preferably at least 1.8, more preferably at least 1.9, more preferably at least 2. The ratio between the length of the aerosol-cooling element and the length of the support element may be up to 2.75, more preferably up to 2.6, more preferably up to 2.5.

[0114] For example, in some embodiments, the ratio between the length of the aerosol-cooling element and the length of the support element can be between 1.5 and 2.75. In these embodiments, the aerosol-cooling element has a length that is significantly greater than the length of the support element. In other embodiments, the ratio between the length of the aerosol-cooling element and the length of the support element can be between 1.5 and 2.6, or between 1.6 and 2.6, or between 1.7 and 2.6, or between 1.8 and 2.5, or between 1.9 and 2.5, or between 2 and 2.5.

[0115] Preferably, the aerosol-generating article is non-ventilated or substantially non-ventilated along the aerosol-cooling element and the support element. In such embodiments, there is therefore substantially no dilution of the aerosol as it passes through the aerosol-generating article, and the aerosol is not cooled by the ingress of outside air. Therefore, the desired degree of cooling of the aerosol must occur due to cooling of the aerosol as it passes through the aerosol-cooling element.

[0116] As defined above, aerosol-generating articles according to the invention further comprise a strip of aerosol-generating substrate.

[0117] Preferably, the strip of aerosol-generating substrate has a length of at least 8 mm, more preferably at least 9 mm, more preferably at least 10 mm. Preferably, the length of the strip of aerosol-generating substrate is less than 16 mm, more preferably less than 15 mm, more preferably less than 14 mm. For example, the strip of aerosol-generating substrate can have a length between 8 mm and 16 mm, or between 9 mm and 15 mm, or between 10 mm and 14 mm. In a particularly preferred embodiment, the strip of aerosol-generating substrate has a length of about 12 mm.

[0118] Preferably, the ratio of the length of the strip of aerosol-generating substrate to the overall length of the aerosol-generating article is at least 0.10, more preferably at least 0.15, more preferably at least 0.20, more preferably at least 0.25. Preferably, the ratio of the length of the strip of aerosol-generating substrate to the overall length of the aerosol-generating article is less than 0.50, more preferably less than 0.45, more preferably less than 0.40, more preferably less than 0.35. For example, the ratio of the length of the strip of aerosol-generating substrate to the overall length of the aerosol-generating article may be between 0.1 and 0.5, or between 0.15 and 0.45, or between 0.2 and 0.4, or between 0.25 and 0.35.

[0119] Preferably, the strip of aerosol-generating substrate has an outer diameter substantially equal to the outer diameter of the aerosol-generating article.

[0120] Preferably, the strip of aerosol-generating substrate has an outer diameter of at least 5 mm, more preferably at least 6 mm, and more preferably at least 7 mm. Prior to insertion of the aerosol-generating article into the aerosol-generating device, the strip of aerosol-generating substrate preferably has an outer diameter of less than 12 mm, more preferably less than 10 mm, and more preferably less than 8 mm. For example, the outer diameter may be between 5 mm and 12 mm, or between 6 mm and 10 mm, or between 7 mm and 8 mm. In a particularly preferred embodiment, the strip of aerosol-generating substrate has an outer diameter of approximately 7.1 mm.

[0121] Preferably, the strip of aerosol-generating substrate has a substantially uniform cross-section along the length of the strip.Particularly preferably, the strip of aerosol-generating substrate has a substantially circular cross-section prior to insertion of the aerosol-generating article into the aerosol-generating device.

[0122] The aerosol-generating substrate may be a solid aerosol-generating substrate. Suitable types of material for use in the aerosol-generating substrate are described below, and include, for example, tobacco cut filler, homogenised tobacco material such as cast leaf, aerosol-generating films and gel compositions.

[0123] Preferably, the aerosol-generating substrate comprises an aerosol-forming agent. The aerosol-forming agent may be any suitable known compound or mixture of compounds that facilitates the formation of a dense and stable aerosol during use. The aerosol-forming agent may facilitate the aerosol being substantially resistant to thermal degradation at temperatures typically applied during use of the aerosol-generating article. Suitable aerosol-forming agents are, for example, polyols such as, for example, triethylene glycol, 1,3-butylene glycol, propylene glycol, and glycerol; esters of polyols such as, for example, glycerol mono-, di-, or triacetate; aliphatic esters of mono-, di-, or polycarboxylic acids such as, for example, dimethyl dodecanedioate and dimethyl tetradecanedioate; and combinations thereof.

[0124] Preferably, the aerosol former comprises one or more of glycerol and propylene glycol. The aerosol former may consist of glycerol or propylene glycol or a combination of glycerol and propylene glycol.

[0125] In certain embodiments, the aerosol-generating substrate preferably comprises at least 5% by weight of an aerosol-forming agent, more preferably at least 10% by weight of an aerosol-forming agent, and more preferably at least 15% by weight of an aerosol-forming agent, based on the dry weight of the aerosol-generating substrate. In such embodiments, the aerosol-generating substrate preferably comprises no more than 30% by weight of an aerosol-forming agent, more preferably no more than 25% by weight of an aerosol-forming agent, and more preferably no more than 20% by weight of an aerosol-forming agent, based on the dry weight of the aerosol-generating substrate. For example, the aerosol-forming agent content of the aerosol-generating substrate may be between 5% and 30% by weight, or between 10% and 25% by weight, or between about 15% and about 20% by weight, based on the dry weight of the aerosol-generating substrate. In such embodiments, the aerosol-forming agent content is therefore relatively low.

[0126] In other embodiments, the aerosol-generating substrate preferably comprises at least 40% aerosol-forming agent by weight of the aerosol-generating substrate, more preferably at least 45% aerosol-forming agent by weight, and more preferably at least 50% aerosol-forming agent by weight. In such embodiments, the aerosol-generating substrate preferably comprises no more than 80% aerosol-forming agent by weight of the aerosol-generating substrate, more preferably no more than 75% aerosol-forming agent by weight, and more preferably no more than 70% aerosol-forming agent by weight. For example, the aerosol-forming agent content of the aerosol-generating substrate can be between 40% and 80% by weight, or between 45% and 75% by weight, or between about 50% and about 70% by weight, based on dry weight. In such embodiments, the aerosol-forming agent content is therefore relatively high.

[0127] In some preferred embodiments, the aerosol generating substrate comprises a tobacco material. For example, the aerosol generating substrate may comprise a tobacco material that has been chopped. For example, as described in more detail below, the tobacco material that has been chopped may be in the form of a cut filler. Alternatively, the tobacco material that has been chopped may be in the form of a chopped material of a homogenized tobacco material. The suitable homogenized tobacco material that is used in the present invention has been described below.

[0128] In the context of this specification, the term "cut filler" is used to describe a blend of chopped plant material, such as tobacco plant material, including in particular one or more of leaves, processed stems and ribs, homogenised plant material.

[0129] Cut filler may also include other post-cut filler tobaccos or additions.

[0130] Preferably, the cut filler comprises at least 25% plant leaves, more preferably at least 50% plant leaves, still more preferably at least 75% plant leaves, and most preferably at least 90% plant leaves. Preferably, the plant material is one of tobacco, mint, tea, and clove. Most preferably, the plant material is tobacco. However, the present application is equally applicable to other plant materials having the ability to release substances upon the application of heat and subsequently form an aerosol.

[0131] The cut filler suitable for use with the present application can be generally similar to cut fillers used for conventional smoking articles. The cut width of the cut filler can preferably be between 0.3 millimetres and 2.0 millimetres, or between 0.5 millimetres and 1.2 millimetres, or between 0.6 millimetres and 0.9 millimetres.

[0132] Preferably, the strands have a length of between about 10 millimetres and about 40 millimetres prior to the strands being collated to form the rod of aerosol-generating substrate.

[0133] In preferred embodiments, the weight of the cut filler is between 25 milligrams and 150 milligrams, preferably between 30 milligrams and 125 milligrams, more preferably between 40 milligrams and 100 milligrams. This amount of cut filler generally allows for sufficient material for aerosol formation during early puffs.

[0134] Preferably, the cut filler is impregnated with an aerosol-former. Impregnating the cut filler can be done by spraying or by other suitable application methods. The aerosol-former can be applied to the blend during the preparation of the cut filler. For example, the aerosol-former can be applied to the blend in a direct conditioning casing cylinder (DCCC). Conventional machinery can be used to apply the aerosol-former to the cut filler. Suitable aerosol-formers are set out above.

[0135] Preferably, the aerosol-former in the cut filler comprises one or more of glycerol and propylene glycol. The aerosol-former can consist of glycerol or propylene glycol or a combination of glycerol and propylene glycol.

[0136] In other preferred embodiments, the aerosol-generating substrate comprises homogenised plant material, preferably homogenised tobacco material.

[0137] As used herein, the term "homogenized plant material" includes any plant material formed by the agglomeration of plant particles. For example, a homogenized tobacco material sheet or web for use in the aerosol-generating substrate of the present invention may be formed by agglomerating particles of tobacco material obtained by comminuting, grinding or crushing plant material and optionally one or more of tobacco leaves and tobacco stems. The homogenized plant material may be produced by casting, extrusion, papermaking, or any other suitable process known in the art.

[0138] The homogenised plant material may be provided in any suitable form.

[0139] In some embodiments, the homogenised plant material may be in the form of one or more sheets.As used herein with reference to the present invention, the term "sheet" describes a laminar element having a width and length that is substantially greater than its thickness.

[0140] The homogenized plant material may be in the form of a plurality of pellets or microparticles.

[0141] Homogenized plant material can be in the form of multiple stocks, strips or fragments.As used herein, term " stock " describes elongated element material, and its length is significantly greater than its width and thickness.Term " stock " should be considered to contain strips, thin strips and any other homogenized plant material with similar form.The stock of homogenized plant material can be formed by the sheet material of homogenized plant material, for example, by cutting or chopping, or by other methods, for example, by extrusion process.

[0142] The aerosol-former content of the homogenised tobacco material is preferably within the range defined above for aerosol-generating substrates having relatively low aerosol-former contents.

[0143] In other preferred embodiments, the aerosol-generating substrate is in the form of an aerosol-generating film comprising a cellulose-based film-forming agent, nicotine, and an aerosol-forming agent. The aerosol-generating film may further comprise a cellulose-based strengthening agent. The aerosol-generating film may further comprise water, preferably 30% by weight or less of water.

[0144] As used herein, the term "film" is used to describe a solid, layered element whose thickness is less than its width or length. A film can be self-supporting. In other words, the film can have cohesive and mechanical properties such that, even if the film is cast onto a supporting surface, it can be separated from the supporting surface. Alternatively, the film can be placed on a support or sandwiched between other materials. This can enhance the mechanical stability of the film.

[0145] The aerosol-forming agent content of the aerosol-forming film is within the range defined above for aerosol-forming substrates having relatively high aerosol-forming agent contents.

[0146] In the context of the present invention, the term "cellulose-based film-forming agent" is used to describe a cellulose polymer capable of forming a continuous film, either alone or in the presence of an auxiliary thickener. Preferably, the cellulose-based film-forming agent is selected from hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), ethylcellulose (EC), hydroxyethylmethylcellulose (HEMC), hydroxyethylcellulose (HEC), hydroxypropyl cellulose (HPC), and combinations thereof. In a particularly preferred embodiment, the cellulose-based film-forming agent is HPMC.

[0147] The aerosol-generating film may have a cellulose-based film-forming agent content of between 10 wt% and 40 wt%, alternatively between 15 wt% and 35 wt%, or alternatively between 20 wt% and 30 wt% on a dry weight basis.

[0148] Preferably, the aerosol-generating film further comprises a cellulose-based strengthening agent.Preferably, the cellulose-based strengthening agent is selected from the group consisting of cellulose fibers, microcrystalline cellulose (MCC), cellulose powder and combinations thereof.

[0149] The aerosol-generating film may have a cellulose-based strengthening agent content of between 0.5 and 40 wt% on a dry weight basis, or between 5 and 30 wt% on a dry weight basis, or between 10 and 25 wt% on a dry weight basis.

[0150] The aerosol-generating film may further comprise carboxymethylcellulose, preferably sodium carboxymethylcellulose.The aerosol-generating film may have a carboxymethylcellulose content of between 1 wt% and 15 wt%, or between 2 wt% and 12 wt%, or between 4 wt% and 10 wt% on a dry weight basis.

[0151] The aerosol-generating film preferably comprises nicotine. As used herein with respect to the present invention, the term "nicotine" is used to describe nicotine, nicotine base, or nicotine salts. In embodiments where the aerosol-generating film comprises nicotine base or nicotine salts, the amounts of nicotine recited herein are the amount of freebase nicotine or the amount of protonated nicotine, respectively.

[0152] The aerosol-generating film may comprise natural nicotine or synthetic nicotine.

[0153] The aerosol-generating film may comprise one or more monobasic nicotine salts.As used herein in relation to the present invention, the term "monobasic nicotine salt" is used to describe a nicotine salt of a monobasic acid.

[0154] Preferably, the aerosol-generating film comprises between 0.5 wt% and 10 wt% nicotine, or between 1 wt% and 8 wt% nicotine, or between 2 wt% and 6 wt% nicotine on a dry weight basis.

[0155] The aerosol-generating film may be a substantially tobacco-free aerosol-generating film.

[0156] In preferred embodiments, the aerosol generating film comprises an acid. More preferably, the aerosol generating film comprises one or more organic acids. Even more preferably, the aerosol generating film comprises one or more carboxylic acids. In particularly preferred embodiments, the acid is lactic acid, benzoic acid, fumaric acid or levulinic acid.

[0157] Preferably, the aerosol generating film comprises between 0.25 and 3.5 weight percent acid on a dry weight basis, or between 0.5 and 3 weight percent acid, or between 1 and 2.5 weight percent acid.

[0158] The aerosol generating film can have a thickness of about 0.1 millimeter to about 1 millimeter, more preferably about 0.1 millimeter to about 0.75 millimeter, even more preferably about 0.1 millimeter to about 0.5 millimeter. In particularly preferred embodiments, a layer of the film-forming composition is formed having a thickness of about 50 micrometers to 400 micrometers, more preferably about 100 micrometers to 200 micrometers.

[0159] Optionally, the aerosol generating film can be provided within an aerosol generating substrate on a suitable carrier element.

[0160] In alternative embodiments of the application, the aerosol generating substrate can comprise a gel composition comprising nicotine, at least one gelling agent and an aerosol former. The gel composition is preferably substantially tobacco-free.

[0161] The preferred weight ranges for nicotine in the gel composition are the same as those defined above in relation to the aerosol generating film.

[0162] The gel composition preferably comprises at least 50 weight percent aerosol former on a dry weight basis, more preferably at least 60 weight percent aerosol former, more preferably at least 70 weight percent aerosol former. The gel composition can comprise up to 80 weight percent aerosol former. The aerosol former in the gel composition is preferably glycerol.

[0163] The gel composition preferably comprises at least one gelling agent. Preferably, the gel composition comprises a total amount of gelling agent in the range of about 0.4 weight percent to about 10 weight percent, or about 0.5 weight percent to about 8 weight percent, or about 1 weight percent to about 6 weight percent, or about 2 weight percent to about 4 weight percent, or about 2 weight percent to about 3 weight percent.

[0164] The term "gelling agent" means a compound that homogenously forms a solid medium or supporting matrix that results in a gel when added in an amount of about 0.3 weight percent to a mixture of 50 weight percent water / 50 weight percent glycerol. Gelling agents include, but are not limited to, hydrogen-bond crosslinking gelling agents and ionically crosslinking gelling agents.

[0165] The term "hydrogen bond cross-linking gelling agent" refers to a gelling agent that forms non-covalent cross-links or physical cross-links via hydrogen bonds. The hydrogen bond cross-linking gelling agent may include one or more of galactomannan, gelatin, agarose, konjac gum, or agar. The hydrogen bond cross-linking gelling agent may preferably include agar.

[0166] The term "ionic crosslinking gelling agent" refers to a gelling agent that forms non-covalent crosslinks or physical crosslinks through ionic bonds. The ionic crosslinking gelling agent may include low acyl gellan gum, pectin, kappa carrageenan, iota carrageenan, or alginate. The ionic crosslinking gelling agent may preferably include low acyl gellan gum.

[0167] The gelling agent may comprise one or more biopolymers. The biopolymer may be formed from a polysaccharide.

[0168] Biopolymers include, for example, gellan gum (natural, low acyl gellan gum, high acyl gellan gum, preferably low acyl gellan gum), xanthan gum, alginates (alginic acid), agar, guar gum, etc. The composition may preferably include xanthan gum. The composition may include two biopolymers. The composition may include three biopolymers. The composition may include substantially equal weights of the two biopolymers. The composition may include substantially equal weights of the three biopolymers.

[0169] The gel composition may also include a viscosity increasing agent. The viscosity increasing agent in combination with the hydrogen bonding cross-linking gelling agent and the ion bonding cross-linking gelling agent appears to unexpectedly support the solid medium and maintain the gel composition even when the gel composition includes high levels of glycerol.

[0170] The term "viscosity increasing agent" refers to a compound that, when homogeneously added in an amount of 0.3 wt. % to a 50 wt. % water / 50 wt. % glycerol mixture at 25°C, increases viscosity without causing gel formation, the mixture remaining or remaining fluid.

[0171] The gel composition preferably includes a viscosity increasing agent in the range of about 0.2 wt % to about 5 wt %, or about 0.5 wt % to about 3 wt %, or about 0.5 wt % to about 2 wt %, or about 1 wt % to about 2 wt %.

[0172] The viscosity increasing agent may include one or more of xanthan gum, carboxymethyl cellulose, microcrystalline cellulose, methyl cellulose, gum arabic, guar gum, lambda-carrageenan or starch. The viscosity increasing agent may preferably include xanthan gum.

[0173] The gel composition may also include divalent cations. Preferably, the divalent cations include calcium ions, such as calcium lactate in solution. For example, divalent cations (such as calcium ions) can help form a gel in a composition that includes a gelling agent, such as an ionically crosslinked gelling agent. Ionic effects can aid gel formation. The divalent cations can be present in the gel composition in a range of about 0.1% to about 1% by weight, or about 0.5% by weight.

[0174] The gel composition may further comprise an acid. The acid may comprise a carboxylic acid, such as levulinic acid or lactic acid.

[0175] The gel composition preferably includes some water. When the gel composition includes some water, the gel composition is more stable. Preferably, the gel composition includes water in an amount of from about 8% to about 32% by weight, or from about 15% to about 25% by weight, or from about 18% to about 22% by weight, or about 20% by weight.

[0176] Preferably, when a gel composition is used, the aerosol-generating substrate comprises a porous medium loaded with the gel composition.The term "porous" is used herein to refer to a material that provides a plurality of pores or openings that allow air to pass through the material.

[0177] In certain embodiments of the present invention, the aerosol-generating article further comprises one or more elongated susceptor elements within the strip of aerosol-generating substrate. For example, the one or more elongated susceptor elements may be arranged substantially longitudinally within the strip of aerosol-generating substrate and in thermal contact with the aerosol-generating substrate.

[0178] As used herein with reference to the present invention, the term "susceptor element" refers to a material capable of converting electromagnetic energy into heat. When located within a fluctuating electromagnetic field, eddy currents induced in the susceptor element result in heating of the susceptor element. Since the susceptor element is positioned in thermal contact with the aerosol-generating substrate, the aerosol-generating substrate is heated by the susceptor element.

[0179] The term "elongated" when used to describe a susceptor element means that the length dimension of the susceptor element is greater than its width dimension or its thickness dimension, such as greater than twice its width dimension or its thickness dimension.

[0180] The susceptor element is arranged substantially longitudinally within the strip of aerosol-generating substrate. This means that the length dimension of the elongated susceptor element is arranged generally parallel to the longitudinal direction of the strip, for example within plus or minus 10 degrees of the longitudinal direction of the strip. In a preferred embodiment, the elongated susceptor element may be positioned at a radially central position within the strip and extend along the longitudinal axis of the strip.

[0181] The susceptor element is preferably in the form of a pin, bar, strip or blade.

[0182] The susceptor element preferably has a width of 1 to 5 mm.

[0183] The thickness of the susceptor element may typically be from 0.01 mm to 2 mm, such as from 0.5 mm to 2 mm. In some embodiments, the susceptor element preferably has a thickness from 10 microns to 500 microns, more preferably from 10 microns to 100 microns.

[0184] Preferably, the length of the elongate susceptor element is equal to or shorter than the length of the aerosol-generating segment in which the elongate susceptor element is comprised.Preferably, the elongate susceptor element has the same length as the aerosol-generating strip in which the elongate susceptor element is comprised.

[0185] The susceptor element may be formed from any material that is capable of being inductively heated to a temperature sufficient to generate an aerosol from the aerosol-generating substrate.Preferably the susceptor element comprises metal or carbon.

[0186] Preferred susceptor elements may comprise or consist of a ferromagnetic material, such as a ferromagnetic alloy, ferritic iron, or a ferromagnetic steel or stainless steel. Suitable susceptor elements may be or comprise aluminium.

[0187] Preferably, the strip of aerosol-generating substrate is defined by a wrapper.The wrapper may be a paper wrapper or a non-paper wrapper.

[0188] Suitable paper wrappers for use in particular embodiments of the present invention are known in the art and include, but are not limited to, cigarette papers; and filter segment wrappers. Suitable non-paper wrappers for use in particular embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco material.

[0189] Aerosol-generating articles according to the present disclosure may further comprise an upstream section located upstream of the strip of aerosol-generating substrate. The upstream section is preferably located immediately upstream of the strip of aerosol-generating substrate. The upstream section preferably extends between the upstream end of the aerosol-generating article and the strip of aerosol-generating substrate. The upstream section may comprise one or more upstream elements located upstream of the strip of aerosol-generating substrate.

[0190] The upstream element advantageously prevents direct physical contact with the upstream end of the strip of aerosol-generating substrate.In addition, the presence of the upstream element helps to prevent any loss of the substrate, which may be advantageous, for example, if the substrate contains granular plant material.

[0191] Where the rod of aerosol-generating substrate comprises shredded tobacco (such as tobacco cut filler), the upstream section or elements thereof may additionally help prevent loose tobacco particles from being lost from the upstream end of the article. This may be particularly important, for example, when the shredded tobacco has a relatively low density.

[0192] The upstream element may be a porous rod element. Preferably, the upstream element has a porosity of at least 50% in the longitudinal direction of the aerosol-generating article. More preferably, the upstream element has a porosity of between 50% and 90% in the longitudinal direction. The porosity of the upstream element in the longitudinal direction is defined by the ratio of the cross-sectional area of ​​the material forming the upstream element to the internal cross-sectional area of ​​the aerosol-generating article at the location of the upstream element.

[0193] The upstream element may be made of a porous material or may include a plurality of openings. For example, this may be achieved by laser perforation. Preferably, the plurality of openings are evenly distributed over the cross section of the upstream element.

[0194] The porosity or permeability of the upstream element may advantageously be designed to provide a particular overall resistance to draw (RTD) to the aerosol-generating article without substantially affecting the filtration provided by other parts of the article.

[0195] The upstream element may be formed from a material that is impermeable to air.In such embodiments, the aerosol-generating article may be configured such that air flows into the strip of aerosol-generating substrate via suitable ventilation means provided in the packaging.

[0196] The upstream element may be made of any material suitable for use in an aerosol-generating article. For example, the upstream element may be made of the same material as one of the other components of the aerosol-generating article (e.g., the mouthpiece, the cooling element, or the support element). Suitable materials for forming the upstream element include filter materials, ceramics, polymeric materials, cellulose acetate, cardboard, zeolites, or an aerosol-generating matrix. Preferably, the upstream element is formed from a cellulose acetate rod.

[0197] Preferably, the upstream element is formed from a heat-resistant material. For example, preferably, the upstream element is formed from a material that resists temperatures up to 350 degrees Celsius. This ensures that the upstream element is not adversely affected by the heating means used to heat the aerosol-generating substrate.

[0198] In certain preferred embodiments, the upstream element is formed from a solid cylindrical rod element having a filled cross-section. Such rod elements may be referred to as "plain" elements. Solid rod elements may be porous, but do not have a tubular form and therefore do not provide any longitudinal flow channels. Solid rod elements preferably have a substantially uniform cross-section.

[0199] In such embodiments, the upstream element preferably has a resistance to draw (RTD) of less than 25 mmH2O, or less than 22 mmH2O, or less than 20 mmH2O. Preferably, in such embodiments, the upstream element has an RTD of at least 10 mmH2O, or at least 12 mmH2O, or at least 14 mmH2O, or at least 16 mmH2O. For example, the upstream element may have an RTD between 10 mmH2O and 25 mmH2O, or between 12 mmH2O and 22 mmH2O, or between 14 mmH2O and 20 mmH2O, or between 16 mmH2O and 20 mmH2O.

[0200] In other embodiments, the upstream element is formed from a hollow tubular segment defining a longitudinal lumen that provides an unrestricted flow path. In such embodiments, as described above, the upstream element can provide protection for the aerosol-generating substrate while having minimal impact on the overall resistance to draw (RTD) and filtration properties of the article.

[0201] Preferably, the diameter of the longitudinal lumen of the hollow tubular segment forming the upstream element is at least about 4 mm, more preferably at least about 4.5 mm, more preferably at least about 5 mm, and more preferably at least about 5.5 mm. Preferably, the diameter of the longitudinal lumen is maximized to minimize the RTD of the upstream segment or its upstream element. The internal diameter of the upstream element may be about 5.1 mm.

[0202] Preferably, the wall thickness of the hollow tubular segment is less than about 2 mm, more preferably less than about 1.5 mm, and more preferably less than about 1.25 mm.The wall thickness of the hollow tubular segment defining the upstream element may be about 1 mm.

[0203] In such embodiments, the upstream element preferably has an RTD of less than 10 mmH2O, more preferably less than 5 mmH2O, and more preferably less than 2.5 mmH2O. Preferably, in such embodiments, the upstream element has an RTD of at least 0.1 mmH2O, or at least about 0.25 mmH2O, or at least about 0.5 mmH2O. For example, the upstream element may have an RTD between 0.1 mmH2O and 10 mmH2O, or between 0.25 mmH2O and 5 mmH2O, or between 0.5 mmH2O and 2.5 mmH2O.

[0204] Preferably, the upstream element has an outer diameter substantially equal to the outer diameter of the aerosol-generating article. Preferably, the outer diameter of the upstream element before any compression is between 6 and 8 mm, more preferably between 7 and 7.5 mm. Preferably, the upstream element has an outer diameter of approximately 7.1 mm.

[0205] Preferably, the upstream element has a length of between 2 and 8 mm, more preferably between 3 and 7 mm, more preferably between 4 and 6 mm. In a particularly preferred embodiment, the upstream element has a length of about 5 mm.

[0206] The upstream element is preferably defined by a wrapper, such as a stick pack.The upstream element is preferably connected to the strip of aerosol-generating substrate and optionally at least a part of the downstream section by means of an outer wrapper as described herein.

[0207] Preferably, the aerosol-cooling element has a negligible level of RTD. For example, preferably, the aerosol-cooling element has an RTD of less than 2 mmH2O, more preferably less than 1.5 mmH2O, more preferably less than 1 mmH2O, more preferably less than 0.5 mmH2O, and most preferably about 0 mmH2O.

[0208] Aerosol-generating articles according to the invention may further comprise a downstream filter segment.The downstream filter segment may be located at the downstream end of the aerosol-generating article.The downstream end of the downstream filter segment may define the downstream end of the aerosol-generating article.

[0209] The downstream filter segment may be located downstream of the aerosol-cooling element as described above.The downstream filter segment may extend between the aerosol-cooling element and the downstream end of the aerosol-generating article.

[0210] The downstream filter segment is preferably a solid rod, which may also be described as a "plain" rod and is non-tubular. Thus, the filter segment preferably has a substantially uniform cross-section.

[0211] The downstream filter segment is preferably formed from a fibrous filter material. The fibrous filter material can be used to filter the aerosol generated by the aerosol-generating substrate. Suitable fibrous filter materials will be known to the skilled person. Particularly preferably, at least one downstream filter segment comprises a cellulose acetate filter segment formed from cellulose acetate tow.

[0212] In certain preferred embodiments, the downstream section comprises a single downstream filter segment.In alternative embodiments, the downstream section comprises two or more downstream filter segments axially aligned in end-to-end abutting relationship with each other.

[0213] Preferably, the downstream filter segment has a low particle filtration efficiency.

[0214] Preferably, the downstream filter segment is defined by the stick wrap.Preferably, the downstream filter segment is non-ventilated, such that air does not enter the aerosol-generating article along the downstream filter segment.

[0215] The downstream filter segment is preferably connected to one or more of the adjacent upstream components of the aerosol-generating article by means of a tipping wrapper.

[0216] Preferably, the downstream filter segment has an outer diameter substantially equal to the outer diameter of the aerosol-generating article.The outer diameter of the downstream filter segment may be substantially the same as the outer diameter of the hollow tubular cooling element.

[0217] Preferably, the outer diameter of the downstream filter segment is between 5 mm and 12 mm, more preferably between 6 mm and 10 mm, more preferably between 7 mm and 8 mm. In some embodiments, the outer diameter of the downstream filter segment may be less than 7 mm, such as between 5 mm and 7 mm, or between 6 mm and 7 mm.

[0218] As described above, the downstream filter segment can be formed from a fibrous filter material. The downstream filter segment can be formed from a porous material. The downstream filter segment can be formed from a biodegradable material. The downstream filter segment can be formed from a cellulosic material such as cellulose acetate.

[0219] The downstream filter segment may be formed from a polylactic acid based material. The downstream filter segment may be formed from a bioplastic material (preferably a starch based bioplastic material). The downstream filter segment may be manufactured by injection molding or by extrusion.

[0220] The length of the downstream filter segment may be between 5 mm and 25 mm, or between 10 mm and 25 mm, or between 5 mm and 20 mm, or between 10 mm and 20 mm, or between 10 mm and 15 mm.

[0221] The ratio of the length of the downstream filter segment to the length of the aerosol-cooling element is preferably at least 1, more preferably at least 1.1, more preferably at least 1.2, more preferably at least 1.3, more preferably at least 1.4. The ratio of the length of the downstream filter segment to the length of the aerosol-cooling element may be up to 2, preferably up to 1.8.

[0222] The downstream filter segment preferably has a resistance to draw (RTD) of less than 15 mmH2O, or less than 12 mmH2O, or less than 10 mmH2O. Preferably, the downstream filter segment has an RTD of at least 2 mmH2O, or at least 4 mmH2O, or at least 6 mmH2O. For example, the RTD of the downstream filter segment may be between 2 mmH2O and 15 mmH2O, or between 4 mmH2O and 12 mmH2O, or between 6 mmH2O and 10 mmH2O. In a particularly preferred embodiment, the downstream filter segment has an RTD of approximately 8.5 mmH2O.

[0223] The aerosol-generating article preferably has an overall length of 40 mm to 80 mm, or 40 mm to about 70 mm, or 40 mm to about 60 mm, or 45 mm to about 80 mm, or about 45 mm to about 70 mm, or 45 mm to 60 mm, or 50 mm to 80 mm, or 50 mm to about 70 mm, or about 50 mm to about 60 mm. In an exemplary embodiment, the overall length of the aerosol-generating article is about 45 mm.

[0224] The aerosol-generating article preferably has an outer diameter of about 5 mm to about 12 mm, or about 6 mm to about 12 mm, or about 7 mm to about 12 mm, or about 5 mm to about 10 mm, or about 6 mm to about 10 mm, or about 7 mm to about 10 mm, or about 5 mm to about 8 mm, or about 6 mm to about 8 mm, or about 7 mm to about 8 mm. In other embodiments, the aerosol-generating article has an outer diameter of less than 7 mm.

[0225] The overall RTD of the aerosol-generating article is preferably at least 10 mm H2O, more preferably at least 15 mm H2O, more preferably at least 20 mm H2O, more preferably at least 25 mm H2O, more preferably at least 30 mm H2O.

[0226] The overall RTD of the aerosol-generating article is preferably no more than 70 mm H2O, more preferably no more than 60 mm H2O, more preferably no more than 55 mm H2O, more preferably no more than 50 mm H2O, more preferably no more than 45 mm H2O.

[0227] For example, the overall RTD of the aerosol-generating article may be between 10 mm H2O and 70 mm H2O, or between 15 mm H2O and 60 mm H2O, or between 20 mm H2O and 55 mm H2O, or between 25 mm H2O and 45 mm H2O, or between 30 mm H2O and 45 mm H2O.

[0228] According to the present invention, an aerosol generating system is also provided, which includes an aerosol generating article and an aerosol generating device according to the present invention as described in detail above, and the aerosol generating device includes a device cavity for receiving the aerosol generating article and at least one heating element arranged at the periphery of the device cavity or around the periphery of the device cavity.

[0229] An aerosol-generating device includes a body or housing defining a device cavity. The device cavity may extend between a distal end and an oral end or a proximal end. The distal end of the device cavity may be a closed end, and the proximal end of the device cavity may be an open end. The aerosol-generating article may be inserted into the device cavity via the open end of the device cavity. The device cavity may be cylindrical to conform to the same shape of the aerosol-generating article.

[0230] The aerosol generating device further comprises a heater comprising one or more heating elements.The heater may be any suitable type of heater.

[0231] In some embodiments, the heater is arranged to heat the outer surface of the aerosol-generating substrate. In some embodiments, the heater is arranged to be inserted into the aerosol-generating substrate when the aerosol-generating substrate is received in the cavity. The heater may be positioned within the cavity of the device.

[0232] The heater may include a single heater element or multiple heater elements. Any suitable type of heater element may be used. The heater may include at least one of a resistive heating element and an inductive heating assembly. The heater may include an external heater or an external heating element.

[0233] The heater may externally heat the strip of aerosol-generating substrate when the aerosol-generating article is received in the aerosol-generating device. Such an external heater may be provided on at least one side of the strip of aerosol-generating substrate when the strip of aerosol-generating substrate is received in the heating chamber of the aerosol-generating device.

[0234] The heater may include at least one resistive heating element. The at least one resistive heating element may be any suitable type of resistive heating element. In some embodiments, the heater includes only one resistive heating element. In some embodiments, the heater includes a plurality of resistive heating elements. The heater may include at least one resistive heating element. Preferably, the heater assembly includes a plurality of resistive heating elements. Preferably, the resistive heating elements are electrically connected in parallel.

[0235] In some embodiments, the at least one heating element comprises an electrically insulating substrate, wherein the at least one resistive heating element is disposed on the electrically insulating substrate.

[0236] In some embodiments, the heater comprises an induction heating assembly. The induction heating assembly may comprise an inductor coil. The aerosol generating device may comprise a power supply configured to provide a high frequency oscillating current to the inductor coil.

[0237] The heater may comprise an induction heating element. The induction heating element may be a susceptor element. In these embodiments, the susceptor element is preferably positioned in contact with the aerosol-generating substrate. In some embodiments, the susceptor element is located in the aerosol-generating device. In these embodiments, the susceptor element may be located in a heating chamber. The aerosol-generating device may comprise only one susceptor element. The aerosol-generating device may comprise multiple susceptor elements. In some embodiments, the susceptor element is preferably arranged to heat the outer surface of the aerosol-generating substrate.

[0238] The susceptor element can comprise any suitable material. Suitable materials for the elongated susceptor element include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel, nickel-containing compounds, titanium, and metal composites. Some susceptor elements comprise metal or carbon. Advantageously, the susceptor element can comprise or be composed of a ferromagnetic material, such as ferritic iron, a ferromagnetic alloy (e.g., ferromagnetic steel or stainless steel), ferromagnetic particles, and ferrites. Suitable susceptor elements can be or comprise aluminum.

[0239] As described in more detail above, in some embodiments where the aerosol-generating device comprises an induction coil, the aerosol-generating article may comprise at least one susceptor element.

[0240] The aerosol-generating device may include an airflow channel extending between a channel inlet and a channel outlet. The airflow channel may be configured to establish fluid communication between an interior of the device cavity and an exterior of the aerosol-generating device. The airflow channel of the aerosol-generating device may be defined within a body of the aerosol-generating device to enable fluid communication between an interior of the heating chamber and an exterior of the aerosol-generating device. When the aerosol-generating article is received within the heating chamber, the airflow channel may be configured to provide airflow into the article to deliver the generated aerosol to a user drawing in from a mouth end of the article.

[0241] The aerosol generating device may include a power source. The power source may be a DC power source. In some embodiments, the power source is a battery.

[0242] A non-exhaustive list of non-limiting examples is provided below.Any one or more features of these examples may be combined with any one or more features of another example, embodiment or aspect described herein.

[0243] EX1. An aerosol-generating article for generating an inhalable aerosol when heated, the aerosol-generating article comprising: a strip of an aerosol-generating substrate; a support element downstream of the strip of aerosol-generating substrate, the support element comprising a first hollow tubular element, the first hollow tubular element providing one or more unrestricted flow channels defining a hollow interior region, wherein the cross-sectional area of ​​the hollow interior region is at least 80% of the total cross-sectional area of ​​the first hollow tubular element; and an aerosol-cooling element downstream of the support element.

[0244] EX2. An aerosol-generating article according to example EX1, wherein the aerosol-cooling element comprises a second hollow tubular element and a gathered sheet of material within the second hollow tubular element, the gathered sheet defining a plurality of longitudinal flow channels.

[0245] EX3. An aerosol-generating article according to example EX1, wherein the aerosol-cooling element defines one or more longitudinal airflow channels and has a total internal surface area of ​​at least 300 mm2.

[0246] EX4. The aerosol-generating article according to any preceding example, wherein the cross-sectional area of ​​the hollow interior region is at least 90% of the total cross-sectional area of ​​the first hollow tubular element.

[0247] EX5. The aerosol-generating article according to any preceding example, wherein the first hollow tubular element of the aerosol-cooling element has an inner diameter D1 of at least 6 mm.

[0248] EX6. The aerosol-generating article according to any preceding example, wherein the first hollow tubular element of the aerosol-cooling element has an inner diameter D1 of at least 6.5 mm.

[0249] EX7. The aerosol-generating article according to any preceding example, wherein the inner diameter D1 of the first hollow tubular element is less than 7.3 mm.

[0250] EX8. The aerosol-generating article according to any preceding example, wherein the wall thickness of the first hollow tubular element is less than 0.5 mm.

[0251] EX9. The aerosol-generating article according to any preceding example, wherein the wall thickness of the first hollow tubular element is less than 0.35 mm.

[0252] EX10. The aerosol-generating article according to any preceding example, wherein the wall thickness of the first hollow tubular element is at least 0.1 mm.

[0253] EX11. The aerosol-generating article according to any preceding example, wherein the first hollow tubular element is a paper tube formed from one or more paper layers.

[0254] EX12. The aerosol-generating article according to example EX11, wherein the first hollow tubular element is a paper tube formed from a plurality of overlapping paper layers.

[0255] EX13. An aerosol-generating article according to example EX12, wherein the plurality of overlapping paper layers are helically wound around the longitudinal axis of the first hollow tubular element.

[0256] EX14. The aerosol-generating article according to any one of examples EX11 to EX13, wherein each paper layer of the paper tube has a thickness between 30 micrometers and 200 micrometers.

[0257] EX15. An aerosol-generating article according to example EX14, wherein the paper layers forming the paper tube have different thicknesses from each other.

[0258] EX16. An aerosol-generating article according to example EX15, wherein the paper tube comprises one or more layers of a first paper material and one or more layers of a second paper material, wherein the thickness of the second paper material is at least 25 microns greater than the thickness of the first paper material.

[0259] EX17. An aerosol-generating article according to any one of examples EX11 to EX116, wherein each paper layer of the paper tube has a grammage of between 25 g / m 2 and 150 g / m 2 .

[0260] EX18. An aerosol-generating article according to example EX17, wherein the paper layers forming the paper tube have different grammagnesias from each other.

[0261] EX19. An aerosol-generating article according to example EX17 or EX18, wherein the paper tube comprises one or more layers of a first paper material and one or more layers of a second paper material, wherein the grammage of the second paper material is at least 25 g / m2 greater than the grammage of the first paper material.

[0262] EX20. The aerosol-generating article according to any one of examples EX11 to EX19, wherein the paper tube comprises at least one hydrophobic paper layer.

[0263] EX21. An aerosol-generating article according to example EX20, wherein the hydrophobic paper layer provides the inner surface of the paper tube.

[0264] EX22. An aerosol-generating article according to example EX20 or EX21, wherein the hydrophobic paper layer comprises a hydrophobic coating applied to a surface thereof.

[0265] EX23. The aerosol-generating article according to any one of examples EX20 to EX22, wherein the hydrophobic paper layer comprises polyvinyl alcohol, silicon, or wax.

[0266] EX24. The aerosol-generating article according to any preceding example, wherein the first hollow tubular element comprises a hollow peripheral wall defining the hollow interior region and one or more internal protrusions extending from the peripheral wall into the hollow interior region.

[0267] EX25. An aerosol-generating article according to example EX24, wherein the one or more internal protrusions are integrally formed with the peripheral wall.

[0268] EX26. An aerosol-generating article according to example EX24 or EX25, wherein the one or more internal protrusions divide the hollow interior region of the first hollow tubular element into a plurality of channels.

[0269] EX27. An aerosol-generating article according to any preceding example, wherein the support element has a length between 5 mm and 15 mm.

[0270] EX28. An aerosol-generating article according to any preceding example, wherein the support element has a length of less than 10 mm.

[0271] EX29. The aerosol-generating article according to any preceding example, wherein the ratio between the length of the support element and the overall length of the aerosol-generating article substrate is at least 0.13.

[0272] EX30. The aerosol-generating article according to any preceding example, wherein the aerosol-cooling element comprises a gathered sheet of polymeric material.

[0273] EX31. An aerosol-generating article according to example EX30, wherein the aerosol-cooling element comprises a gathered sheet of polylactic acid.

[0274] EX32. An aerosol-generating article according to any preceding example, wherein the aerosol-cooling element is formed from a gathered sheet of material having a specific surface area between 10 mm2 / mg weight and 100 mm2 / mg weight.

[0275] EX33. The aerosol-generating article according to any preceding example, wherein the aerosol-cooling element has a total surface area of ​​between 300 mm2 / mm length and about 1000 mm2 / mm length.

[0276] EX34. An aerosol-generating article according to any preceding claim, wherein the aerosol-cooling element has a porosity of between 50% and 90%.

[0277] EX35. The aerosol-generating article according to any preceding example, wherein the second hollow tubular element has an inner diameter D2 of at least 6 mm.

[0278] EX36. The aerosol-generating article according to any preceding example, wherein the second hollow tubular element has an inner diameter D2 of at least 6.8 mm.

[0279] EX37. The aerosol-generating article according to any preceding example, wherein the second hollow tubular element has an inner diameter D2 of less than 7.3 mm.

[0280] EX38. The aerosol-generating article according to any preceding example, wherein a ratio between the inner diameter of the first hollow tubular element and the inner diameter of the second hollow tubular element is at least 0.8.

[0281] EX39. The aerosol-generating article according to any preceding example, wherein a ratio between the inner diameter of the first hollow tubular element and the inner diameter of the second hollow tubular element is less than 1.25.

[0282] EX40. The aerosol-generating article according to any preceding example, wherein the wall thickness of the second hollow tubular element is at least 0.1 mm.

[0283] EX41. The aerosol-generating article according to any preceding example, wherein the wall thickness of the second hollow tubular element is less than 0.5 mm.

[0284] EX42. The aerosol-generating article according to any preceding example, wherein the second hollow tubular element is formed from a paper-based material.

[0285] EX43. An aerosol-generating article according to any preceding example, wherein the aerosol-cooling element has a length of between 10 mm and 25 mm.

[0286] EX44. The aerosol-generating article according to any preceding example, wherein the aerosol-cooling element has a length of at least 12 mm.

[0287] EX45. The aerosol-generating article according to any preceding example, wherein a ratio between the length of the aerosol-cooling element and the overall length of the aerosol-generating article is at least 0.25.

[0288] EX46. The aerosol-generating article according to any preceding example, wherein a ratio between the length of the aerosol-cooling element and the length of the support element is at least 1.5.

[0289] EX47. An aerosol-generating article according to any preceding example, wherein the aerosol-cooling element is non-ventilated.

[0290] EX48. The aerosol-generating article according to any preceding example, wherein the strip of aerosol-generating substrate has a length of at least 8 mm.

[0291] EX49. An aerosol-generating article according to any preceding example, wherein the rod of aerosol-generating substrate comprises homogenized tobacco material.

[0292] EX50. An aerosol-generating article according to any preceding example, wherein the rod of aerosol-generating substrate comprises tobacco cut filler.

[0293] EX51. The aerosol-generating article according to any preceding example, wherein the strip of aerosol-generating substrate comprises a cellulose-based film-forming agent, nicotine, and an aerosol-forming agent.

[0294] EX52. The aerosol-generating article according to any preceding example, wherein the strip of aerosol-generating substrate comprises one or more elongated susceptor elements.

[0295] EX53. The aerosol-generating article according to any preceding example, further comprising an upstream element positioned upstream of the strip of aerosol-generating substrate.

[0296] EX54. The aerosol-generating article according to any preceding example, further comprising a downstream filter segment downstream of the aerosol-cooling element.

[0297] EX55. An aerosol generating system comprising an aerosol generating article according to any of the preceding examples and an aerosol generating device, the aerosol generating device comprising a device cavity for receiving the aerosol generating article and at least one heating element arranged at or around the periphery of the device cavity.

[0298] In the following, the present invention will be further described with reference to the figures of the accompanying drawings, in which:

[0299] Figure 1 shows a schematic side cross-sectional view of an aerosol-generating article according to the present invention; and

[0300] Figure 2 Shown for Figure 1 A perspective view (not drawn to scale) of an alternative support element for an aerosol-generating article.

[0301] Figure 1 The aerosol-generating article 10 shown in FIG comprises a strip 12 of aerosol-generating substrate 12 and a downstream section 14 at a position downstream of the strip 12 of aerosol-generating substrate. Thus, the aerosol-generating article 10 extends from an upstream or distal end 18 to a downstream or mouth end 20.

[0302] The aerosol-generating article has an overall length of approximately 45 mm.

[0303] The downstream section 14 comprises a support element 22 positioned immediately downstream of the strip 12 of aerosol-generating substrate, the support element 22 being longitudinally aligned with the strip 12. Figure 1 In the embodiment of FIG, the upstream end of the support element 22 abuts the downstream end of the strip of aerosol-generating substrate 12. In addition, the downstream section 14 includes an aerosol-cooling element 24 positioned immediately downstream of the support element 22, the aerosol-cooling element 24 being longitudinally aligned with the strip 12 and the support element 22. Figure 1 In the embodiment of FIG. 2 , the upstream end of aerosol-cooling element 24 abuts the downstream end of support element 22 .

[0304] Support element 22 includes a first hollow tubular element 26. First hollow tubular element 26 is configured as a paper tube formed of three spirally wound paper layers. The first inner paper layer has a thickness of 137 microns and a grammage of 120 gsm. The second middle paper layer has a thickness of 100 microns and a grammage of 78 gsm. The third outer paper layer has a thickness of 45 microns and a grammage of 32 gsm.

[0305] The first hollow tubular member 26 defines a lumen 28 that extends from an upstream end 30 of the first hollow tubular member to a downstream end 32 of the first hollow tubular member 26. The lumen 28 is substantially hollow and thus allows for substantially unrestricted airflow along the lumen 28. The lumen 28 has a substantially circular cross-section.

[0306] The first hollow tubular element 26, and therefore the support element 22, does not substantially affect the overall RTD of the aerosol-generating article 10. In particular, the RTD of the first hollow tubular element 26 is substantially 0 mm H2O.

[0307] The first hollow tubular member 26 has a length of about 8 mm, an outer diameter of about 7.25 mm, and an inner diameter (D1) of about 6.9 mm. Therefore, the thickness of the peripheral wall of the first hollow tubular member 26 is about 0.18 mm.

[0308] The lumen 28 of the first hollow tubular member 26 corresponds to the hollow interior region of the first hollow tubular member 26. The cross-sectional area of ​​the hollow interior region is approximately 37.4 square millimeters. The total cross-sectional area of ​​the first hollow tubular member 26 is approximately 41.3 square millimeters. Therefore, the cross-sectional area of ​​the hollow interior region accounts for approximately 90% of the total cross-sectional area of ​​the first hollow tubular member.

[0309] The aerosol-cooling element 24 includes a second hollow tubular element 34 comprising a gathered sheet 35 of polylactic acid defining a plurality of longitudinal airflow channels. The second hollow tubular element 34 is provided in the form of a paper tube. The second hollow tubular element 34 defines an interior cavity 36 extending from an upstream end 38 of the second hollow tubular element to a downstream end 40 of the second hollow tubular element 34. As depicted, the interior cavity 36 is filled with the gathered sheet 35 of polylactic acid. The aerosol-cooling element 24 does not substantially affect the overall RTD of the aerosol-generating article 10. The aerosol-cooling element 24 is non-ventilated.

[0310] The aerosol-cooling element 24 has a length of approximately 18 mm and an outer diameter of approximately 7.25 mm. The inner diameter (D2) of the second hollow tubular element is approximately 6.9 mm. Thus, the thickness of the peripheral wall of the second hollow tubular element 34 is approximately 0.18 mm. Thus, the ratio between the inner diameter (D2) of the second hollow tubular element 34 and the inner diameter (D1) of the first hollow tubular element 26 is approximately 1.

[0311] exist Figure 1 In the embodiment of FIG. 4 , the downstream section 14 further comprises a mouthpiece element 42 positioned immediately downstream of the aerosol-cooling element 24. Figure 1 As shown in the Figures, the upstream end of the mouthpiece element 42 abuts the downstream end 40 of the second hollow tubular element 34.

[0312] The mouthend element 42 is provided in the form of a cylindrical filter segment of low density cellulose acetate.

[0313] The mouthpiece element 42 has a length of about 7 mm and an outer diameter of about 7.25 mm. The RTD of the mouthpiece element 42 is about 10.5 mm H2O.

[0314] The strip 12 comprises an aerosol-generating substrate of one of the types described above.

[0315] The rod 12 of aerosol-generating substrate had an outer diameter of approximately 7.25 mm and a length of approximately 12 mm.

[0316] The aerosol-generating article 10 comprises an outer wrapper incorporating a strip 12 of an aerosol-generating substrate, a support element 22 and an aerosol-cooling element 24 .

[0317] Figure 2 An alternative support element 122 is shown which may replace Figure 1 . The support element 22 is used in the aerosol-generating article 10 shown in FIG. The support element 122 comprises a hollow tubular element 126 having a peripheral wall 110 that defines a hollow interior region 120 of the hollow tubular element 100. The hollow tubular element 126 further comprises three internal protrusions 130 that are formed from a sheet material and each extend from a first point 131 at the peripheral wall 110 across the hollow interior region 120 to a second point 132 at the peripheral wall 110.

[0318] The peripheral wall 110 and the inner projection 130 are integrally formed from the same sheet of paper. Substantially all of the portion of the sheet forming the peripheral wall 110 forms the curved outer surface of the hollow tubular element 126.

[0319] The internal protrusions 130 each depend from the peripheral wall 110 along a first fold line 141 of the sheet of material, wherein the first fold line 141 is located at a first point 131 of the peripheral wall 110, and wherein the first fold line 141 extends along substantially the entire length of the hollow tubular element 126. Each of the internal protrusions 130 also depends from the peripheral wall 110 along a second fold line 142 of the sheet of material, wherein the second fold line 142 is located at a second point 132 at the peripheral wall 110, and wherein the second fold line 142 extends along substantially the entire length of the hollow tubular element 126.

[0320] Thus, the inner protrusion 130 also extends substantially along the entire length of the hollow tubular element 126. In fact, the inner protrusion has substantially the same length as the hollow tubular element 126.

[0321] The hollow tubular member 126 has a length of approximately 8 mm.

[0322] The hollow tubular element 126 has a cross-section that is constant along the entire length of the hollow tubular element 126 .

[0323] Both the first fold line 141 and the second fold line 142 are parallel to the longitudinal axis of the hollow tubular element 126. Thus, the first fold line 141 and the second fold line 142 are parallel to each other.

[0324] like Figure 2 As shown in FIG, each inner protrusion 130 includes a third fold line 143 of the sheet, wherein the third fold line 143 is parallel to and equidistant from the first fold line 141 and the second fold line 142. The third fold line 143 defines a tip of the inner protrusion 130.

[0325] The cross-section of the inner protrusion 130 is selected such that the cross-sectional area of ​​the hollow interior region 120 is at least 80% of the total cross-sectional area of ​​the hollow tubular element 126 .

[0326] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers representing amounts, quantities, percentages, etc. should be understood to be modified by the term "about" in all cases. Moreover, all ranges include the disclosed maximum and minimum points, and include any intermediate ranges therein that may be specifically listed or may not be listed herein. Therefore, in this article, the number A is understood to be 10% of A±A. In this article, the number A may be considered to be a numerical value within the general standard error of measurement of the property modified by the number A. In certain cases used in the appended claims, the number A may deviate from the percentages listed above, provided that the amount of A deviation does not substantially affect the basic characteristics and novel features of the invention claimed. Moreover, all ranges include the disclosed maximum and minimum points, and include any intermediate ranges therein that may be specifically listed or may not be listed herein.

Claims

1. An aerosol-generating article for generating an inhalable aerosol upon heating, the aerosol-generating article comprising: strips of aerosol-generating substrate; a support element downstream of the strip of aerosol-generating substrate, the support element comprising a first hollow tubular element providing one or more unrestricted flow passages defining a hollow interior region, wherein the cross-sectional area of ​​the hollow interior region is at least 80% of the total cross-sectional area of ​​the first hollow tubular element; An aerosol-cooling element downstream of the support element comprises a second hollow tubular element and a gathered sheet of material within the second hollow tubular element, the gathered sheet defining a plurality of longitudinal flow channels.

2. An aerosol-generating article according to claim 1, wherein the first hollow tubular element of the support element has a wall thickness of less than 0.5 mm.

3. An aerosol-generating article according to any preceding claim, wherein the aerosol-generating article is substantially non-ventilated along the support element and the aerosol-cooling element.

4. The aerosol-generating article according to any one of claims 1 to 3, wherein the first hollow tubular element comprises a peripheral wall defining a single unrestricted flow channel, and wherein the inner diameter D1 of the first hollow tubular element is at least 6 mm.

5. An aerosol-generating article according to any one of claims 1 to 3, wherein the first hollow tubular element comprises a peripheral wall defining the hollow interior region and one or more internal protrusions extending from the peripheral wall into the hollow interior region.

6. An aerosol-generating article according to any preceding claim, wherein the first hollow tubular element of the support element is a paper tube formed from a plurality of overlapping paper layers.

7. An aerosol-generating article according to claim 6, wherein the plurality of overlapping paper layers are helically wound around the longitudinal axis of the first hollow tubular element.

8. An aerosol-generating article according to claim 6 or 7, wherein the paper tube comprises one or more layers of a first paper material and one or more layers of a second paper material, wherein the thickness of the second paper material is greater than the thickness of the first paper material.

9. An aerosol-generating article according to any one of claims 6 to 8, wherein the paper tube comprises a hydrophobic coating on the inner surface.

10. An aerosol-generating article according to any preceding claim, wherein the gathered sheet of material in the aerosol-cooling element has a total surface area of ​​at least 300 mm2.

11. An aerosol-generating article according to any preceding claim, wherein the inner diameter D2 of the second hollow tubular element is at least 6 mm.

12. The aerosol-generating article according to claim 9, wherein a ratio of the inner diameter D1 of the first hollow tubular element to the inner diameter D2 of the second hollow tubular element is between 0.8 and 1.

2.

13. An aerosol-generating article according to any preceding claim, wherein the aerosol-cooling element comprises a gathered sheet of polylactic acid (PLA).

14. An aerosol-generating article according to any preceding claim, further comprising a mouthpiece element downstream of the aerosol-cooling element, the mouthpiece element comprising at least one mouthpiece filter segment formed from fibrous filter material.

15. An aerosol-generating system comprising an aerosol-generating article according to any one of claims 1 to 14 and an aerosol-generating device, the aerosol-generating device comprising a heating chamber for receiving the aerosol-generating article and at least one heating element disposed within the heating chamber.

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