An aerosol-generating article comprising a hollow tubular element and at least one wrapper

Abstract

An aerosol-generating article (100, 200, 300) comprising an aerosol-generating substrate (20), a hollow tubular element (30), and at least one wrapper (10, 40) circumscribing the hollow tubular element (30) and forming at least one transverse wall (41, 43) adjacent to an end of the hollow tubular element (30) The, or each of the, at least one transverse wall (41, 43) delimits an aperture (42, 44) for fluid communication between an interior of the hollow tubular element (32) and an exterior of the hollow tubular element.

Description

[0001] FTR3988 / PCT (P / 90987.W001) AN AEROSOL-GENERATING ARTICLE COMPRISING A HOLLOW TUBULAR ELEMENT AND AT LEAST ONE WRAPPER

[0002] The present disclosure relates to an aerosol-generating article comprising an aerosolgenerating substrate and adapted to produce an inhalable aerosol upon heating.

[0003] Aerosol-generating articles in which an aerosol-generating substrate is heated, rather than combusted, are known in the art. Typically, in such heated aerosol-generating articles, an aerosol is generated by the transfer of heat from a heat source to a physically separate aerosol-generating substrate, which may be located in physical contact with, within, 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 to the aerosol-generating substrate. The volatile compounds are then entrained in air that is drawn through the aerosol-generating article. As the volatile compounds cool, they condense to form an aerosol.

[0004] It has been known to provide aerosol-generating articles with one or more additional elements upstream or downstream of the aerosol-generating substrate that are configured to enhance the experience of a consumer. For example, WO 2013 / 120565 A2 discloses an aerosol-generating article comprising an aerosol-cooling element for cooling an aerosol formed from the aerosol-generating substrate. In one embodiment disclosed in WO 2013 / 120565 A2, a hollow cellulose acetate tube is located immediately downstream of the aerosol-generating substrate and an aerosol-cooling element made from a sheet of polylactic acid is positioned downstream of the hollow cellulose acetate tube. It is described that a function of the hollow cellulose acetate tube is to prevent the aerosol-generating substrate from being forced downstream when a heating element is inserted into the aerosol-generating substrate and the aerosol-cooling element is to reduce the temperature of the aerosol. As another example, WO 2013 / 098410 A2 discloses an aerosol-generating article comprising a front plug positioned upstream of the aerosol-generating substrate. It is described that the front plug may prevent egress of the aerosol-generating substrate from upstream end of the aerosol-generating article during handling and shipping, and may assist location of the aerosol-generating substrate at a predetermined distance from the upstream end of the rod for optimum engagement with a heat source. However, at least some of these additional elements may be costly or complicated to manufacture, and costly or complicated to dispose of. Additionally, it may be challenging to optimise these elements for different types of aerosolgenerating substrates and desired user experiences.

[0005] WO 2022 / 074235 A1 discloses an aerosol-generating article comprising a tubular element having an end wall delimiting an opening. The tubular element is formed by folding an end portion of the tubular element to form the end wall, and the tubular element can bepositioned upstream ordownstream of the aerosol-generating substrate. WO 2022 / 074235 A 1 seeks to address at least some of the problems faced with known upstream and known downstream elements by replacing them with the tubular element. However, it would be desirable to provide an aerosol-generating article with an element upstream or downstream of an aerosol-generating substrate that may be easier and more cost-effective to manufacture than those in the prior art and that may also be more straightforward to optimise for different types of aerosol-generating substrates and desired user experiences.

[0006] According to the present disclosure, there is provided an aerosol-generating article. The aerosol-generating article comprises an aerosol-generating substrate. The aerosolgenerating article comprises a hollow tubular element. The aerosol-generating article comprises at least one wrapper circumscribing the hollow tubular element and forming at least one transverse wall adjacent to an end of the hollow tubular element. The, or each of the, at least one transverse wall delimits an aperture for fluid communication between an interior of the hollow tubular element and an exterior of the hollow tubular element.

[0007] The wrapped hollow tubular element is versatile and can provide a variety of functions depending on its arrangement within the aerosol-generating article. For example, when located downstream of the aerosol-generating substrate, the wrapped hollow tubular element may function as one or more of: an aerosol-cooling element, a support element and a mouthpiece element. As another example, when located upstream of the aerosol-generating substrate, the wrapped hollow tubular element may function as a front plug. Advantageously, this may allow a reduction in the number of elements within the aerosol-generating article, thereby reducing cost and manufacturing complexity.

[0008] The wrapped hollow tubular element is made from separate components: at least one wrapper and the hollow tubular element. This means that each component can be suitably optimised for its respective function unlike some prior art tubular elements where the tubular element and its end wall are made from the same component. For example, the hollow tubular element may be made from a material having properties optimised for bending or crush resistance and thermal conductivity whilst the at least one wrapper, and thereby the at least one transverse wall, may be made from a material having properties optimised for air impermeability and liquid repulsion. Advantageously, this may lead to an aerosol-generating article that is cheaper to manufacture and may be more optimised.

[0009] Optionally, the aerosol-generating article comprises a downstream section extending from the downstream end of the aerosol-generating substrate to the downstream end of the aerosol-generating article. Optionally, the hollow tubular element is located downstream of the aerosol-generating substrate. Optionally, the hollow tubular element is located within the downstream section. Advantageously, as volatile compounds and air move downstream from the aerosol-generating substrate, heat can be dissipated to the structure of the hollow tubularelement allowing the volatile compounds to cool and condense to form an aerosol. This allows the hollow tubular element to function as a cooling element. Additionally, the at least one transverse wall can act as a barrier to prevent the aerosol-generating substrate, or parts of the aerosol-generating substrate, from migrating downstream where they could be inhaled by a consumer.

[0010] Optionally, the hollow tubular element is located at, or towards, the downstream end of the downstream section or the aerosol-generating article. Optionally, the downstream end of the hollow tubular element is equal to or less than 5 millimetres from the downstream end of the downstream section or the aerosol-generating article. Optionally, the downstream end of the hollow tubular element is equal to or less than 3 millimetres from the downstream end of the downstream section or the aerosol-generating article. Optionally, the downstream end of the hollow tubular element is equal to or less than 1 millimetres from the downstream end of the downstream section or the aerosol-generating article. Advantageously, the hollow tubular element may therefore act as a mouthpiece element and support a consumer’s lips when they draw on the downstream end of the aerosol-generating article.

[0011] Optionally, the hollow tubular element has a length equal to or greater than 80 percent of a length of the downstream section. Optionally, the hollow tubular element has a length equal to or greater than 90 percent of the length the downstream section. Optionally, the hollow tubular element has a length equal to or greater than 95 percent of the length the downstream section. Optionally, the hollow tubular element has a length equal to or greater than 98 percent of the length the downstream section. Advantageously, the hollow tubular element occupying the majority of the region downstream of the aerosol-generating substrate provides a relatively large volume for aerosol-formation and aerosol-cooling. Additionally, the hollow tubular element occupying the majority of the region downstream of the aerosol-generating substrate may reduce the number of components in the aerosol-generating article compared to some known aerosol-generating article and may thereby reduce the manufacturing cost and complexity. Moreover, the hollow tubular element occupying the entire region downstream of the aerosol-generating substrate may provide increased levels of aerosol delivered to the consumer due to a lower level of filtration. This is particularly beneficial for aerosol-generating substrates in the form of an aerosol-generating film.

[0012] Optionally, the downstream section has a length of at least 40 percent of a length of the aerosol-generating article. Optionally, the downstream section has a length of at least 50 percent of a length of the aerosol-generating article. Optionally, the downstream section has a length of at least 60 percent of a length of the aerosol-generating article. Advantageously, providing a downstream section that has a relatively long length provides a relatively large volume for aerosol-formation and aerosol-cooling.Optionally, the downstream section has a resistance to draw equal to or less than about 30 mmH20. Optionally, the downstream section has a resistance to draw equal to or less than about 20 mmH20. Optionally, the downstream section has a resistance to draw equal to or less than about 10 mmH20. Optionally, the downstream section has a resistance to draw of about 0 mmH20. Advantageously, this may mean that the downstream section provides little contribution to the overall resistance to draw of the aerosol-generating article, thereby allowing the resistance to draw of the aerosol-generating article to be control by the configuration of the aerosol-generating substrate.

[0013] Optionally, the downstream section does not comprise any component comprising plastic. Optionally, the downstream section does not comprise any component comprising cellulose acetate. Optionally, any element located within the downstream section is made from paper or cardboard. Advantageously, this may make the aerosol-generating article more environmentally-friendly, particularly when it comes to disposing of the aerosol-generating article.

[0014] Optionally, the downstream section defines an unrestricted airflow passage extending the entire length of the downstream section and having a minimum diameter equal to the minimum diameter of any aperture delimited by the, or each of the, at least one transverse wall. Advantageously, this may mean the resistance to draw of the downstream section is controlled by the configuration of the at least one transverse wall and aperture.

[0015] Optionally, the aerosol-generating article comprises an upstream section extending from the upstream end of the aerosol-generating article to upstream end of the aerosolgenerating substrate. Optionally, the hollow tubular element is located upstream of the aerosol-generating substrate. Optionally, the hollow tubular element is located within the upstream section. Optionally, the hollow tubular element is located at, or towards, the upstream end of the upstream section or aerosol-generating article. Advantageously, the wrapped hollow tubular element may therefore act as a front plug.

[0016] Optionally, the upstream section does not comprise any component comprising plastic. Optionally, the upstream section does not comprise any component comprising cellulose acetate. Optionally, any element located within the upstream section is made from paper or cardboard. Advantageously, this may make the aerosol-generating article more environmentally-friendly, particularly when it comes to disposing of the aerosol-generating article.

[0017] Optionally, the hollow tubular element has a length equal to or greater than 80 percent of a length of the upstream section. Optionally, the hollow tubular element has a length equal to or greater than 90 percent of the upstream section. Optionally, the hollow tubular element has a length equal to or greater than 95 percent of the upstream section. Optionally, the hollow tubular element has a length equal to or greater than 98 percent of the upstream section.Optionally, the hollow tubular element defines an inner cavity extending from an upstream end of the hollow tubular element to a downstream end of the hollow tubular element. Optionally, the inner cavity is substantially empty. Optionally, the inner cavity forms an uninterrupted airflow conduit through the hollow tubular element. Advantageously, the presence of an inner cavity may mean that the hollow tubular element does not significantly contribute to the resistance-to-draw of the aerosol-generating article. Additionally, the inner cavity may provide a region for aerosol formation when the hollow tubular element is positioned downstream of the aerosol-generating substrate.

[0018] Optionally, the inner cavity has a constant diameter along at least 90 percent of the hollow tubular element. Optionally, the inner cavity has a constant diameter along at least 95 percent of the hollow tubular element. Optionally, the inner cavity has a constant diameter along the entire length of the hollow tubular element. An increasing or decreasing diameter of the inner cavity may result in a variation of velocity of airflow through the inner cavity. Therefore, advantageously, providing the inner cavity with a relatively constant velocity along its length may ensure that the airflow through the hollow tubular element has a relatively constant velocity and sufficient time to dissipate heat.

[0019] Optionally, the inner cavity has a diameter equal to or greater than 85 percent, 90 percent, or 95 percent, of the outer diameter of the hollow tubular element. Optionally, the inner cavity has a diameter equal to or less than 98 percent, 95 percent, or 90 percent, of the outer diameter of the hollow tubular element. Optionally, the inner cavity has a diameter between 85 percent and 98 percent of the outer diameter of the hollow tubular element. Optionally, the inner cavity has a diameter between 90 percent and 95 percent of the outer diameter of the hollow tubular element. Advantageously, these ranges provide a trade-off between maximising the internal volume of the hollow tubular element whilst maintain strength of the hollow tubular element. In more detail, an inner cavity having a relatively large diameter may lead to the hollow tubular element having a large volume for aerosol-formation and aerosol-cooling, whereas an inner cavity having a relatively small diameter may lead to the hollow tubular element having a thick wall and, thus, greater strength.

[0020] Optionally, the hollow tubular element comprises a tubular peripheral wall extending from an upstream end of the hollow tubular element to a downstream end of the hollow tubular element. Optionally, the tubular peripheral wall circumscribes the inner cavity. Optionally, an inner surface of the tubular peripheral wall defines a diameter of the inner cavity. Optionally, an outer surface of the tubular peripheral wall defines an outer diameter of the hollow tubular element.

[0021] Optionally, the tubular peripheral wall has a radial thickness of equal to or greater than 200 micrometres. Optionally, the tubular peripheral wall has a radial thickness of equal to orgreater than 300 micrometres. Optionally, the tubular peripheral wall has a radial thickness of equal to or greater than 400 micrometres.

[0022] Optionally, the tubular peripheral wall has a radial thickness of equal to or less than 700 micrometres. Optionally, the tubular peripheral wall has a radial thickness of equal to or less than 600 micrometres. Optionally, the tubular peripheral wall has a radial thickness of equal to or less than 500 micrometres.

[0023] Optionally, the tubular peripheral wall has a radial thickness of between 200 micrometres and 700 micrometres. Optionally, the tubular peripheral wall has a radial thickness of between 300 micrometres and 600 micrometres. Optionally, the tubular peripheral wall has a radial thickness of between 400 micrometres and 500 micrometres. Advantageously, a radial thickness of between 200 micrometres and 700 micrometres provides a good trade-off between lower cost on the thinner side and structural strength on the thicker side. A radial thickness of between 400 micrometres and 500 micrometres provides this trade-off whilst providing a higher level of structural strength.

[0024] Optionally, the hollow tubular element is substantially tobacco-free or nicotine-free. Optionally, the hollow tubular element comprises biodegradable material. Optionally, the hollow tubular element comprises equal to or greater than 80 percent by weight of biodegradable material. Optionally, the hollow tubular element comprises equal to or greater than 90 percent by weight of biodegradable material. Optionally, the hollow tubular element comprises equal to or greater than 95 percent by weight of biodegradable material. Optionally, the hollow tubular element comprises equal to or greater than 99 percent by weight of biodegradable material. Advantageously, this may make the aerosol-generating article more environmentally-friendly, particularly when it comes to disposing of the aerosol-generating article.

[0025] Optionally, the hollow tubular element is a spirally wound tube. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, that has been wound into an overlapping spiral to form the hollow tubular element. Advantageously, a spirally wound tube has good structural strength whilst being relatively straightforward to manufacture.

[0026] Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, formed into a tube forming an overlapping region in which opposing longitudinal ends of the sheet of material overlap. Optionally, the opposing longitudinal ends of the sheet of material are bonded together in the overlapping region, for example with an adhesive. Optionally, the overlapping region extends equal to or greater than 80 percent of the length of the hollow tubular element. Optionally, the overlapping region extends the entire length of the hollow tubular element.Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or greater than 50 grams per square metre. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or greater than 60 grams per square metre. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or greater than 70 grams per square metre.

[0027] Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or less than 400 grams per square metre. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or less than 300 grams per square metre. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or less than 200 grams per square metre.

[0028] Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 50 grams per square metre and 400 grams per square metre. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 60 grams per square metre and 200 grams per square metre. Optionally, the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 70 grams per square metre and 200 grams per square metre. A low grammage sheet may be easier to shape into a tube but may have low structural strength, whereas a high grammage sheet may have high structural strength but be harder to shape into a tube. Advantageously, a grammage between 60 grams per square metre and 200 grams per square metre may provide a good trade-off between these two factors.

[0029] Optionally, the hollow tubular element comprises, or consist of, a cellulosic material, such as paper or cardboard. Optionally, the hollow tubular element comprises equal to or greater than 80 percent by weight of cellulosic material, such as paper or cardboard. Optionally, the hollow tubular element comprises equal to or greater than 90 percent by weight of cellulosic material, such as paper or cardboard. Optionally, the hollow tubular element comprises equal to or greater than 95 percent by weight of cellulosic material, such as paper or cardboard. Optionally, the hollow tubular element comprises equal to or greater than 99 percent by weight of cellulosic material, such as paper or cardboard. Advantageously, this may make the aerosol-generating article more environmentally-friendly, particularly when it comes to disposing of the aerosol-generating article.

[0030] Optionally, the hollow tubular element is formed from, or comprises, compressed matter, such as particulate matter, powder or pellets. Optionally, the compressed matter comprises one or both of sorbitol and erythritol. Advantageously, the compressed matter canbe adapted to disaggregate after a predefined period of time, thereby improving the environmental friendliness of the aerosol-generating article. Moreover, it also allows flavour or aroma to be embedded within the structure of the hollow tubular element which may improve user experience.

[0031] Optionally, the hollow tubular element is formed from moulded pulp. Optionally, the hollow tubular element is formed by extrusion, injection moulding, or additive manufacturing.

[0032] Optionally, equal to or greater than 80 percent of a surface area of the inner surface of the hollow tubular element comprises a hydrophobic coating. Optionally, the entire surface area of the inner surface of the hollow tubular element comprises a hydrophobic coating. Optionally, the entire surface area of the hollow tubular element comprises a hydrophobic coating. The hollow tubular element may be exposed to condensed one or more of: volatile compounds, water vapour and saliva. Advantageously, a hydrophobic coating may prevent deterioration of the structural integrity of the hollow tubular element due to such exposure.

[0033] Optionally, the hollow tubular element has a length of equal to or greater than 30 percent of a length of the aerosol-generating article. Optionally, the hollow tubular element has a length of equal to or greater than 40 percent of a length of the aerosol-generating article. Optionally, the hollow tubular element has a length of equal to or greater than 50 percent of a length of the aerosol-generating article. Advantageously, the aerosol-generating article may have a higher resistance to bending deformation the longer the length of the hollow tubular element.

[0034] Optionally, the hollow tubular element has a length equal to or less than 80 percent of a length of the aerosol-generating article. Optionally, the hollow tubular element has a length equal to or less than 70 percent of a length of the aerosol-generating article. Optionally, the hollow tubular element has a length equal to or less than 60 percent of a length of the aerosolgenerating article.

[0035] Optionally, the hollow tubular element has a length between 30 percent and 80 percent of a length of the aerosol-generating article. Optionally, the hollow tubular element has a length between 40 percent and 70 percent a length of the aerosol-generating article. Optionally, the hollow tubular element has a length of between 50 percent and 60 percent a length of the aerosol-generating article.

[0036] Optionally, the at least one transverse wall comprises, or consists of, a downstream transverse wall adjacent to a downstream end of the hollow tubular element. Optionally, the at least one transverse wall comprises no more than one transverse wall adjacent to a downstream end of the hollow tubular element.

[0037] Optionally, the downstream transverse wall abuts the downstream end of the hollow tubular element. Optionally, the downstream transverse wall is spaced, in the longitudinaldirection, from the downstream end of the hollow tubular element by between 1 millimetre and 5 millimetres.

[0038] Optionally, when the hollow tubular element is located downstream of the aerosolgenerating substrate, the downstream transverse wall is located at, or adjacent to, the downstream end of the aerosol-generating article. Optionally, when the hollow tubular element is located downstream of the aerosol-generating substrate, the aperture delimited by the downstream transverse wall forms an air outlet of the aerosol-generating article. Advantageously, the aperture accelerates the air and aerosol as it is delivered to the consumer.

[0039] Optionally, when the hollow tubular element is located upstream of the aerosolgenerating substrate, the downstream transverse wall is adjacent to an upstream end of the aerosol-generating substrate. Optionally, when the hollow tubular element is located upstream of the aerosol-generating substrate, the downstream transverse wall abuts the upstream end of the aerosol-generating substrate. Advantageously, the downstream transverse wall may, therefore, prevent the aerosol-generating substrate from egressing out of the upstream end of the aerosol-generating article.

[0040] Optionally, the at least one transverse wall comprises, or consists of, an upstream transverse wall adjacent to an upstream end of the hollow tubular element. Optionally, the at least one transverse wall comprises no more than one transverse wall adjacent to an upstream end of the hollow tubular element. Advantageously, an upstream transverse wall and aperture may promote turbulent flow downstream the transverse wall which may lead to increased dissipation of heat and increased mixing.

[0041] Optionally, the upstream transverse wall abuts the upstream end of the hollow tubular element. Optionally, the upstream transverse wall is spaced, in the longitudinal direction, from the upstream end of the hollow tubular element by between 1 millimetre and 5 millimetres.

[0042] Optionally, when the hollow tubular element is located upstream of the aerosolgenerating substrate, the upstream transverse wall is located at, or adjacent to, the upstream end of the aerosol-generating article. Optionally, when the hollow tubular element is located upstream of the aerosol-generating substrate, the aperture delimited by the upstream transverse wall forms an air inlet of the aerosol-generating article. Advantageously, the upstream end wall may prevent inadvertent ignition of the aerosol-generating substrate.

[0043] Optionally, when the hollow tubular element is located downstream of the aerosolgenerating substrate, the upstream transverse wall is adjacent to a downstream end of the aerosol-generating substrate. Optionally, when the hollow tubular element is located downstream of the aerosol-generating substrate, the upstream transverse wall abuts the downstream end of the aerosol-generating substrate. Advantageously, the upstream end wallmay prevent the aerosol-generating substrate, or parts thereof, from migrating downstream where they could be inhaled.

[0044] Optionally, the at least one transverse wall comprises, or consists of, both a downstream transverse wall adjacent to a downstream end of the hollow tubular element and an upstream transverse wall adjacent to an upstream end of the hollow tubular element.

[0045] Optionally, the, each of the, or any of the, at least one wrapper comprises a folded end portion forming the at least one transverse wall. For example, the folded end portion may be formed as described in WO 2022 / 074235 A1 or WO 2024 / 133051 A1.

[0046] Optionally, the, each of the, or one or more of the, at least one transverse wall forms an inward flange. That is, the transverse wall extends radially inward from the tubular peripheral wall of the hollow tubular element rather than radially outward. Optionally, the, each of the, or one or more of the, at least one transverse wall is substantially perpendicular to a longitudinal axis of the hollow tubular element.

[0047] Optionally, the, each of the, or one or more of the, at least one transverse wall has a convex curvature. Optionally, the, each of the, or one or more of the, at least one transverse wall having a convex curvature is curled. Optionally, a portion of the, each of the, or one or more of the, at least one transverse wall having a convex curvature is shaped to extend into, or towards, the interior of the hollow tubular element, such as the inner cavity of the hollow tubular element. Optionally, the, each of the, or one or more of the, at least one transverse end wall having a convex curvature defines an airflow passage having a diameter that increases in a longitudinal direction away from the longitudinal centre of the hollow tubular element.

[0048] Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall is in a radially central position the respective transverse wall. For example, the aperture delimited by the upstream transverse wall may be in a radially central position of the upstream transverse wall. Advantageously, this may ensure air and aerosol is distributed evenly across the transverse cross-sectional area of the hollow tubular element. As another example, the aperture delimited by the downstream transverse wall may be in a radially central position of the downstream transverse wall. Advantageously, air and aerosol are drawn away from the tubular peripheral wall of the hollow tubular element. This may be particularly beneficial when the hollow tubular element acts as a mouthpiece element because it my draw hot air and aerosol away from the consumers lips.

[0049] Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall is the only aperture delimited by respective the transverse wall. For example, the aperture delimited by the upstream transverse wall may be the only aperture delimited by upstream transverse wall. For example, the aperture delimited by the downstream transverse wall may be the only aperture delimited by upstream transverse wall.Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a circular transverse cross-sectional shape.

[0050] Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or greater than 40 percent of a diameter of an interior of the hollow tubular element. Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or greater than 50 percent of a diameter of an interior of the hollow tubular element. Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or greater than 60 percent of a diameter of an interior of the hollow tubular element.

[0051] Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or less than 90 percent of a diameter of an interior of the hollow tubular element. Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or less than 80 percent of a diameter of an interior of the hollow tubular element. Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or less than 70 percent of a diameter of an interior of the hollow tubular element.

[0052] Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter between 40 percent and 90 percent of a diameter of an interior of the hollow tubular element. Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter between 50 percent and 80 percent of a diameter of an interior of the hollow tubular element. Optionally, the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter between 60 percent and 70 percent of a diameter of an interior of the hollow tubular element.

[0053] Optionally, the at least one wrapper comprises, or consists of, a wrapper forming one or both of: the downstream transverse wall adjacent to the downstream end of the hollow tubular element and the upstream transverse wall adjacent to the upstream end of the hollow tubular element.

[0054] Optionally, the at least one wrapper comprises, or consist of, a first wrapper forming the downstream transverse wall adjacent to the downstream end of the hollow tubular element and a second wrapper forming the upstream end wall adjacent to the upstream end of the hollow tubular element. Optionally, the first wrapper is in physical contact with the second wrapper. Optionally, the first wrapper circumscribes the second wrapper or the second wrapper circumscribes the first wrapper. Advantageously, the use of separate wrappers for the upstream and downstream transverse walls allows the wrappers to be optimised independently of one another.

[0055] Optionally, where the hollow tubular element is downstream of the aerosol-generating substrate and the at least one wrapper comprises a wrapper forming the downstreamtransverse wall adjacent to the downstream end of the hollow tubular element, the wrapper is an outer wrapper defining an outer surface of the aerosol-generating article. Optionally, the outer wrapper further circumscribes at least a portion of the length of the aerosol-generating substrate. Optionally, the outer wrapper extends from the downstream end of the aerosolgenerating article to an upstream end of the aerosol-generating article. Optionally, the outer wrapper defines the entire circumference of the aerosol-generating article along the entire length of the aerosol-generating article. Advantageously, using the outer wrapper to form the at least one transverse wall may reduce the need for an additional wrapper. Additionally, a downstream transverse wall formed using the outer wrapper may prevent the hollow tubular element from egressing from the downstream end of the aerosol-generating article.

[0056] Optionally, when the hollow tubular element is located downstream of the aerosolgenerating substrate, the, or each of the, at least one wrapper is located downstream of the aerosol-generating substrate. Optionally, when the hollow tubular element is located upstream of the aerosol-generating substrate, the, or each of the, at least one wrapper is located upstream of the aerosol-generating substrate.

[0057] Optionally, the, each of the, or one or more of the, at least one wrapper circumscribes at least 30 percent the length of the hollow tubular element. Optionally, the, each of the, or one or more of the, at least one wrapper circumscribes at least 50 percent the length of the hollow tubular element. Optionally, the, each of the, or one or more of the, at least one wrapper circumscribes the entire length of the hollow tubular element.

[0058] Optionally, the, each of the, or one or more of the, at least one wrapper is in physical contact with the hollow tubular element. Optionally, the, each of the, or one or more of the, at least one wrapper is bonded to the hollow tubular element. Optionally, an inner surface of the, each of the, or one or more of the, at least one wrapper is bonded to an outer surface of the hollow tubular element. Optionally, the, each of the, or one or more of the, at least one wrapper is bonded to the hollow tubular element with an adhesive. Optionally, the, each of the, or one or more of the, at least one wrapper is bonded to the hollow tubular element with a strip, line or bead of adhesive. Optionally, the strip, line or bead of adhesive extends in a longitudinal direction of the hollow tubular element. Optionally, the strip, line or bead of adhesive extends around the entire circumference of the hollow tubular element. Optionally, the adhesive comprises one or more of: a gum, guar gum, and polyvinyl alcohol.

[0059] Optionally, the, each of the, or one or more of the, at least one wrapper comprises, or consist of, a cellulosic material, such as paper or cardboard. Optionally, the, each of the, or one or more of the, at least one wrapper comprises equal to or greater than 80 percent by weight of cellulosic material, such as paper or cardboard. Optionally, the, each of the, or one or more of the, at least one wrapper comprises equal to or greater than 90 percent by weight of cellulosic material, such as paper or cardboard. Optionally, the, each of the, or one or moreof the, at least one wrapper comprises equal to or greater than 95 percent by weight of cellulosic material, such as paper or cardboard. Optionally, the, each of the, or one or more of the, at least one wrapper comprises equal to or greater than 99 percent by weight of cellulosic material, such as paper or cardboard.

[0060] Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or greater than 40 grams per square metre. Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or greater than 50 grams per square metre. Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or greater than 60 grams per square metre.

[0061] Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or less than 150 grams per square metre. Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or less than 130 grams per square metre. Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of equal to or less than 100 grams per square metre.

[0062] Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 40 grams per square metre and 150 grams per square metre. Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 50 grams per square metre and 130 grams per square metre. Optionally, the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 60 grams per square metre and 100 grams per square metre.

[0063] Optionally, the, or each of the, at least one wrapper comprises a sheet of material having a first grammage, or first plurality of grammages, and the hollow tubular element comprises a sheet of material having a second grammage, wherein the second grammage is greater than the first grammage or the maximum grammage in the first plurality of grammages. Optionally, at least 20 percent greater, or at least 40 percent greater, or at least 60 percent greater, or at least 80 percent greater, or at least 100 percent greater.

[0064] Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of equal to or greater than 100 micrometres. Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of equal to or greater than 150 micrometres.Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of equal to or greater than 200 micrometres.

[0065] Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of equal to or less than 400 micrometres. Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of equal to or less than 350 micrometres. Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of equal to or less than 300 micrometres.

[0066] Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of between 100 micrometres and 400 micrometres. Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of between 150 micrometres and 350 micrometres. Optionally, the, each of the, or one or more of the, at least one wrapper has a thickness of between 200 micrometres and 300 micrometres.

[0067] Optionally, the, or each of the, at least one wrapper is formed from a sheet of material having a first thickness, or first plurality of thicknesses, and the hollow tubular element is formed from a sheet of material having a second thickness, wherein the second thickness is greater than the first thickness or the maximum thickness in the first plurality of thicknesses. Optionally, at least 20 percent greater, or at least 40 percent greater, or at least 60 percent greater, or at least 80 percent greater, or at least 100 percent greater.

[0068] Optionally, there is no filter element made from cellulose acetate positioned downstream of the hollow tubular element. Optionally, there is no filter element positioned downstream of the hollow tubular element.

[0069] Optionally, the aerosol-generating article comprises a front plug located upstream of the aerosol-generating substrate. Advantageously, such a front plug may prevent the aerosolgenerating substrate from egressing from the upstream end of the aerosol-generating article. The front plug may also assist locating the aerosol-generating substrate at a predetermined distance from the upstream end of the aerosol-generating article for optimum engagement with a heat source, such as a heating element. The front plug may also make it less likely for a consumer to mistakenly use the aerosol-generating article like a conventional cigarette and ignite the end of the aerosol-generating article.

[0070] Optionally, the front plug is the most upstream element of the aerosol-generating article. Optionally, the front plug is in physical contact with the upstream end of the aerosolgenerating substrate.

[0071] Optionally, the front plug is penetrable by a heating element so that the heating element can contact or penetrate the aerosol-generating substrate. In such embodiments, the aerosolgenerating substrate may shrink into contact with a heating element during an aerosolgenerating phase. The aerosol-generating substrate may also shrink such that its contact with an outer wrapper of the aerosol-generating article is reduced. Without a front plug, thewithdrawal of the heating element from the rod may also result in the withdrawal of the aerosolgenerating substrate due to increased adhesion of the aerosol-generating substrate with the heating element coupled with decreased adhesion of the aerosol-generating substrate with the outer wrapper. However, the front plug may facilitate removal or extraction of the heating element from the rod by restricting the movement of the aerosol-generating substrate towards the distal end of the rod. The front plug may block the passage of the aerosol-generating substrate and therefore prevent the aerosol-generating substrate from being withdrawn from the aerosol-generating article.

[0072] Optionally, the front plug is made from a filter material that allows air to be drawn through the front plug. This may allow a consumer to draw air through the aerosol-generating article via the front plug. The front plug may conveniently be formed from the same material as a conventional mouthpiece filter. For example, the front plug may be formed from a length of cellulose acetate tow. Permeability of the front plug may be varied to help control resistance to draw through the aerosol-generating article. Alternatively, the front plug may be formed from a material that is not permeable to air. In such embodiments, the aerosol-generating article may be configured such that air flows into the aerosol-generating substrate through a sidewall of the aerosol-generating article upstream of the aerosol-generating substrate.

[0073] Optionally, the front plug comprises one or more materials selected from the group comprising ceramic, polymer, biopolymer, metal, zeolite, paper, cardboard, inert material, and inorganic material. Optionally, the front plug has a diameter that is approximately equal to the diameter of the aerosol-generating article. Preferably, the front plug has a diameter between about 5 millimetres and about 10 millimetres. Optionally, the front plug has a length of between about 1 millimetre and about 10 millimetres, between about 2 millimetres and about 8 millimetres, between about 4 millimetres and about 8 millimetres. Optionally, the front plug is cylindrical. Optionally, the front plug has a length of at least 2 millimetres in order to facilitate assembly of the aerosol-generating article, preferably at least 3 millimetres or at least 4 millimetres. Optionally, the front plug has a length of about 5 millimetres. Advantageously, a longer plug may also provide an improved cleaning effect of an inserted heating element as there is a greater amount of the front plug material available for wiping the heating element as the heating element is withdrawn from the plug.

[0074] Optionally, the aerosol-generating substrate is in the form of a rod.

[0075] Optionally, the aerosol-generating substrate has a length of at least 8 millimetres, or a length of at least 9 millimetres, or a length of at least 10 millimetres. Optionally, the length of the aerosol-generating substrate is less than 16 millimetres, or less than 15 millimetres, or less than 14 millimetres. Optionally, the aerosol-generating substrate has a length of between 8 millimetres and 16 millimetres, or between 9 millimetres and 15 millimetres, or between 10millimetres and 14 millimetres. Preferably, the aerosol-generating substrate has a length of about 12 millimetres.

[0076] Optionally, the ratio between the length of the aerosol-generating substrate and the overall length of the aerosol-generating article is at least 0.10, or at least 0.15, or at least 0.20, or at least 0.25. Optionally, the ratio between the length of the aerosol-generating substrate and the overall length of the aerosol-generating article is less than 0.50, or less than 0.45, or less than 0.40, or less than 0.35. Optionally, the ratio between the length of the aerosolgenerating substrate and the overall length of the aerosol-generating article is 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.

[0077] Optionally, the aerosol-generating substrate has an external diameter that is approximately equal to the external diameter of the aerosol-generating article.

[0078] Optionally, the aerosol-generating substrate has an external diameter of at least 5 millimetres, or at least 6 millimetres, or at least 7 millimetres. Optionally, the aerosolgenerating substrate has an external diameter of less than 12 millimetres, or less than 10 millimetres, or less than 8 millimetres. Optionally, the external diameter is between 5 millimetres and 12 millimetres, or between 6 millimetres and 10 millimetres, or between 7 millimetres and 8 millimetres. Preferably, the aerosol-generating substrate has an external diameter of about 7.1 millimetres.

[0079] Optionally, the aerosol-generating substrate has a substantially uniform cross-section along the length of the aerosol-generating substrate. Preferably, the aerosol-generating substrate has a substantially circular cross-section.

[0080] Optionally, the aerosol-generating substrate has a density of at least about 150 milligrams per cubic centimetre, at least about 175 milligrams per cubic centimetre, at least about 200 milligrams per cubic centimetre, or at least about 250 milligrams per cubic centimetre.

[0081] Optionally, the aerosol-generating substrate has a density of less than or equal to about 500 milligrams per cubic centimetre, less than or equal to about 450 milligrams per cubic centimetre, less than or equal to about 400 milligrams per cubic centimetre, or less than or equal to about 350 milligrams per cubic centimetre.

[0082] Optionally, the RTD of the aerosol-generating substrate is at least about 4 millimetres H2O, at least about 5 millimetres H2O, or at least about 6 millimetres H2O.

[0083] Optionally, the RTD of the aerosol-generating substrate is less than or equal to about 10 millimetres H2O, less than or equal to about 9 millimetres H2O, or less than or equal to about 8 millimetres H2O.

[0084] Optionally, the aerosol-generating substrate is a solid aerosol-generating substrate. Suitable types of materials for use in the aerosol-generating substrate are described belowand include, for example, tobacco cut filler, homogenised tobacco material such as cast leaf, aerosol-generating films and gel compositions.

[0085] Optionally, the aerosol-generating substrate comprises an aerosol former. Suitable aerosol formers are for example: polyhydric alcohols such as, for example, triethylene glycol, 1,3-butanediol, propylene glycol and glycerine; esters of polyhydric alcohols 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.

[0086] Preferably, the aerosol former comprises one or more of glycerine and propylene glycol. Optionally, the aerosol former consists of glycerine or propylene glycol or of a combination of glycerine and propylene glycol.

[0087] Optionally, the aerosol-generating substrate comprises at least 5 percent by weight of aerosol former on a dry weight basis of the aerosol-generating substrate, or at least 10 percent by weight on a dry weight basis, or at least 15 percent by weight on a dry weight basis. Optionally, the aerosol-generating substrate comprises no more than 30 percent by weight of aerosol former on a dry weight basis of the aerosol-generating substrate, or no more than 25 percent by weight on a dry weight basis, or no more than 20 percent by weight on a dry weight basis. Optionally, the aerosol former content of the aerosol-generating substrate is between 5 percent and 30 percent by weight, or between 10 percent and 25 percent by weight, or between about 15 percent and about 20 percent by weight, on a dry weight basis. Therefore, the aerosol former content may be relatively low.

[0088] Optionally, the aerosol-generating substrate comprises at least 40 percent by weight of aerosol former on a dry weight basis of the aerosol-generating substrate, or at least 45 percent by weight on a dry weight basis, or at least 50 percent by weight on a dry weight basis. Optionally, the aerosol-generating substrate comprises no more than 80 percent by weight of aerosol former on a dry weight basis of the aerosol-generating substrate, or no more than 75 percent by weight on a dry weight basis, or no more than 70 percent by weight on a dry weight basis. Optionally, the aerosol former content of the aerosol-generating substrate is between 40 percent and 80 percent by weight, or between 45 percent and 75 percent by weight, or between about 50 percent and about 70 percent by weight, on a dry weight basis. Therefore, the aerosol former content may be relatively high.

[0089] Optionally, the aerosol-generating substrate comprises tobacco material. Optionally, the aerosol-generating substrate comprises shredded tobacco material. Optionally, the shredded tobacco material is in the form of cut filler, as described in more detail below. Alternatively, optionally, the shredded tobacco material is in the form of a shredded sheet of homogenised tobacco material. Suitable homogenised tobacco materials for use in the present invention are described below.Optionally, where the aerosol-generating substrate comprises shredded tobacco material in the form of cut filler, the cut filler resembles cut filler used for conventional smoking articles. Optionally, the cut width of the cut filler is 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.

[0090] Optionally, the strands of the cut filler have a length of between about 10 millimetres and about 40 millimetres before the strands are collated to form the aerosol-generating substrate.

[0091] Optionally, the cut filler is soaked with the aerosol former. Soaking the cut filler can be done by spraying or by other suitable application methods. Preferably, the aerosol former in the cut filler comprises one or more of glycerol and propylene glycol. Optionally, the aerosol former may consist of glycerol or propylene glycol or of a combination of glycerol and propylene glycol.

[0092] Optionally, the aerosol-generating substrate comprises homogenised plant material, preferably a homogenised tobacco material.

[0093] Optionally, the homogenised plant material is in the form of one or more sheets. Optionally, the homogenised plant material is in the form of a plurality of pellets or granules. Optionally, the homogenised plant material is in the form of a plurality of strands, strips or shreds.

[0094] Optionally, the aerosol-forming substrate comprises a gathered sheet of homogenised tobacco material. Optionally, the gathered sheet of homogenised tobacco material extends across substantially the entire transverse cross-sectional area of the aerosol-generating article.

[0095] Optionally, the gathered sheet of homogenised tobacco material has a grammage 100 g / m2 and about 300 g / m2.

[0096] Optionally, the gathered sheet of homogenised tobacco material has a thickness of between 50 pm and about 300 pm.

[0097] Optionally, the gathered sheet of homogenised tobacco material is a crimped and gathered sheet of homogenised tobacco material. Optionally, the crimped and gathered sheet of homogenised tobacco material has a plurality of ridges or corrugations substantially parallel to the longitudinal axis of the aerosol-generating article.

[0098] Optionally, the aerosol former content of the homogenised tobacco material is within the ranges defined above for aerosol-generating substrate having a relatively low aerosol former content.

[0099] Optionally, the aerosol-generating substrate is in the form of an aerosol-generating film comprising a cellulosic based film-forming agent, nicotine and the aerosol former. Optionally, the aerosol-generating film further comprise a cellulose based strengthening agent. Optionally,the aerosol-generating film further comprises water, preferably 30 percent by weight of less of water.

[0100] Optionally, the cellulose based film-forming agent is selected from the group consisting of hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), ethylcellulose (EC), hydroxyethyl methyl cellulose (HEMC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), and combinations thereof. Preferably, the cellulose based film-forming agent is HPMC.

[0101] Optionally, the aerosol former content of the aerosol-generating film is within the ranges defined above for aerosol-generating substrates having a relatively high aerosol former content.

[0102] Suitable aerosol-generating films for use as the aerosol-generating substrate are described in WO-A-2020 / 207733 and WO-A-2022 / 074157.

[0103] Optionally, the aerosol-generating film comprises between 0.5 percent and 10 percent by weight of nicotine, or between 1 percent and 8 percent by weight of nicotine, or between 2 percent and 6 percent by weight of nicotine, on a dry weight basis.

[0104] Optionally, the aerosol-generating film is a substantially tobacco-free aerosolgenerating film.

[0105] Optionally, the aerosol-generating substrate comprises a gel composition that includes nicotine, at least one gelling agent and the aerosol former. Preferably, the gel composition is substantially tobacco-free.

[0106] The preferred weight ranges for nicotine in the gel composition are the same as those defined above in relation to aerosol-generating films.

[0107] Suitable gel compositions for use as the aerosol-generating substrate are described in WO-A-2021 / 170642.

[0108] Optionally, the gel composition comprises at least 50 percent by weight of aerosol former, or at least 60 percent by weight, or at least 70 percent by weight of aerosol former, on a dry weight basis. Optionally, the gel composition may comprise up to 80 percent by weight of aerosol former. Preferably, the aerosol former in the gel composition is preferably glycerol.

[0109] Optionally, the aerosol-generating article comprises a susceptor element located in thermal contact with the aerosol-generating substrate. Optionally, the susceptor element is located within the aerosol-generating substrate.

[0110] Optionally, the susceptor element is arranged substantially longitudinally within the aerosol-generating substrate. This means that the length dimension of the susceptor element is arranged to be approximately parallel to the longitudinal direction of the aerosol-generating substrate, for example within plus or minus 10 degrees of parallel to the longitudinal direction of the aerosol-generating substrate. Optionally, the susceptor element is positioned in a radially central position within the aerosol-generating substrate, and extends along the longitudinal axis of the aerosol-generating substate.Optionally, the susceptor element extends to a downstream end of the aerosolgenerating substrate. Optionally, the susceptor element extends to an upstream end of the aerosol-generating substrate. Optionally, the susceptor element has substantially the same length as the aerosol-generating substrate. Optionally, the susceptor element extends from an upstream end of the aerosol-generating substrate to a downstream end of the aerosolgenerating substrate.

[0111] Optionally, the susceptor element is an elongate susceptor element.

[0112] Optionally, the susceptor element is in the form of a pin, rod, strip or blade.

[0113] Optionally, the susceptor element has a length between about 5 millimetres and about 15 millimetres, for example between about 6 millimetres and about 12 millimetres, or between about 8 millimetres and about 10 millimetres.

[0114] Optionally, the susceptor element has a width between about 1 millimetre and about 5 millimetres.

[0115] Optionally, the susceptor element has a thickness between about 0.01 millimetres and about 2 millimetres, for example between about 0.5 millimetres and about 2 millimetres. Optionally, the susceptor element has a thickness between about 10 micrometres and about 500 micrometres, more preferably between about 10 micrometres and about 100 micrometres.

[0116] Optionally, the susceptor element comprises or consists of metal or carbon.

[0117] Optionally, the susceptor element comprises or consists of a ferromagnetic material, for example a ferromagnetic alloy, ferritic iron, or a ferromagnetic steel or stainless steel. Optionally, the susceptor element is, or comprises, aluminium. Optionally, the susceptor element is formed from or comprises 400 series stainless steels, for example grade 410, or grade 420, or grade 430 stainless steel. Different materials will dissipate different amounts of energy when positioned within electromagnetic fields having similar values of frequency and field strength. Thus, parameters of the susceptor element such as material type, length, width, and thickness may all be altered to provide a desired power dissipation within a known electromagnetic field.

[0118] Optionally, the susceptor element comprises a non-metallic core with a metal layer disposed on the non-metallic core, for example metallic tracks formed on a surface of a ceramic core. Optionally, the susceptor element has a protective external layer, for example a protective ceramic layer or protective glass layer encapsulating the susceptor element. Optionally, the susceptor element comprises a protective coating formed by a glass, a ceramic, or an inert metal, formed over a core of susceptor element material.

[0119] Optionally, the susceptor element is a multi-material susceptor element comprising a first susceptor element material and a second susceptor element material. Optionally, the first susceptor element material is disposed in intimate physical contact with the second susceptor element material. Optionally, the second susceptor element material has a Curie temperaturethat is lower than 500 degrees Celsius. Optionally, the first susceptor element material is used primarily to heat the susceptor element when the susceptor element is placed in a fluctuating electromagnetic field. Any suitable material may be used. For example, the first susceptor element material may be aluminium, or may be a ferrous material such as a stainless steel. Optionally, the second susceptor element material is used primarily to indicate when the susceptor element has reached a specific temperature, that temperature being the Curie temperature of the second susceptor element material. Optionally, the Curie temperature of the second susceptor element material can be used to regulate the temperature of the entire susceptor element during operation. Thus, the Curie temperature of the second susceptor element material should be below the ignition point of the aerosol-generating substrate. Suitable materials for the second susceptor element material may include nickel and certain nickel alloys.

[0120] By providing a susceptor element having at least a first and a second susceptor element material, with either the second susceptor element material having a Curie temperature and the first susceptor element material not having a Curie temperature, or first and second susceptor element materials having first and second Curie temperatures distinct from one another, the heating of the aerosol-generating substrate and the temperature control of the heating may be separated. The first susceptor element material is preferably a magnetic material having a Curie temperature that is above 500 degrees Celsius. It is desirable from the point of view of heating efficiency that the Curie temperature of the first susceptor element material is above any maximum temperature that the susceptor element should be capable of being heated to. The second Curie temperature may preferably be selected to be lower than 400 degrees Celsius, preferably lower than 380 degrees Celsius, or lower than 360 degrees Celsius. It is preferable that the second susceptor element material is a magnetic material selected to have a second Curie temperature that is substantially the same as a desired maximum heating temperature. That is, it is preferable that the second Curie temperature is approximately the same as the temperature that the susceptor element should be heated to in order to generate an aerosol from the aerosol-generating substrate. The second Curie temperature may, for example, be within the range of 200 degrees Celsius to 400 degrees Celsius, or between 250 degrees Celsius and 360 degrees Celsius. The second Curie temperature of the second susceptor element material may, for example, be selected such that, upon being heated by a susceptor element that is at a temperature equal to the second Curie temperature, an overall average temperature of the aerosol-generating substrate does not exceed 240 degrees Celsius.

[0121] The aerosol-generating article comprise a ventilation zone. Advantageously, this may increase the cooling of the air and volatile compounds within the interior of the tubular element by drawing in cooler, external air. It may also increase the turbulence within the tubularelement, particularly where the ventilation zone causes air to be drawn into the tubular element in a direction transverse to the longitudinal axis of the tubular element.

[0122] The ventilation zone may be positioned downstream of the aerosol-forming substrate. The ventilation zone may be positioned at a location along the tubular element. For example, the ventilation zone may be positioned longitudinally between the upstream end wall and the downstream end wall of the tubular element. Features of the ventilation zone are described below in respect of the aerosol-generating article. However, it will be appreciated that they may also apply to directly to the tubular element itself.

[0123] The ventilation zone may comprise a plurality of perforations through the peripheral wall of the aerosol-generating article, the tubular element or both the aerosol-generating article and the tubular element. Preferably, the ventilation zone comprises at least one circumferential row of perforations. The ventilation zone may comprise two circumferential rows of perforations. For example, the perforations may be formed during manufacturing of the aerosol-generating article. Preferably, each circumferential row of perforations comprises from 8 to 30 perforations.

[0124] An aerosol-generating article in accordance with the present invention may have a ventilation level of at least about 5 percent.

[0125] The term “ventilation level” is used throughout the present specification to denote a volume ratio between of the airflow admitted into the aerosol-generating article via the ventilation zone (ventilation airflow) and the sum of the aerosol airflow and the ventilation airflow. The greater the ventilation level, the higher the dilution of the aerosol flow delivered to the consumer.

[0126] The aerosol-generating article may typically have a ventilation level of at least about 10 percent, preferably at least about 15 percent, more preferably at least about 20 percent.

[0127] In preferred embodiments, the aerosol-generating article has a ventilation level of at least about 25 percent. The aerosol-generating article preferably has a ventilation level of less than about 60 percent. The aerosol-generating article may have a ventilation level of less than or equal to about 45 percent. More preferably, the aerosol-generating article may have a ventilation level of less than or equal to about 40 percent, even more preferably less than or equal to about 35 percent.

[0128] In a particularly preferred embodiments, the aerosol-generating article has a ventilation level of about 30 percent. The aerosol-generating article may have a ventilation level from about 20 percent to about 60 percent, preferably from about 20 percent to about 45 percent, more preferably from about 20 percent to about 40 percent The aerosol-generating article may have a ventilation level from about 25 percent to about 60 percent, preferably from about 25 percent to about 45 percent, more preferably from about 25 percent to about 40 percent. In further embodiments, the aerosol-generating article has a ventilation level from about 30percent to about 60 percent, preferably from about 30 percent to about 45 percent, more preferably from about 30 percent to about 40 percent. The aerosol-generating article may have a ventilation level of between about 30 percent and about 60 percent. The aerosol-generating article may have a ventilation level of between about 40 percent and about 50 percent.

[0129] In some particularly preferred embodiments, the aerosol-generating article has a ventilation level from about 28 percent to about 42 percent. In some particularly preferred embodiments, the aerosol-generating article has a ventilation level of about 30 percent.

[0130] Embodiments where the ventilation zone is provided at a location along the tubular element may provide a number of advantages. For example, and without wishing to be bound by theory, the inventors have found that the temperature drop caused by the admission of cooler, external air into the tubular element via the ventilation zone may have an advantageous effect on the nucleation and growth of aerosol particles.

[0131] Optionally, the aerosol-generating article has an overall length of from 40 millimetres to 80 millimetres, or from 40 millimetres to about 70 millimetres, or from 40 millimetres to about 60 millimetres, or from 45 millimetres to about 80 millimetres, or from about 45 millimetres to about 70 millimetres, or from 45 millimetres to 60 millimetres, or from 50 millimetres to 80 millimetres, or from 50 millimetres to about 70 millimetres or from about 50 millimetres to about 60 millimetres. Preferably, an overall length of the aerosol-generating article is about 45 millimetres.

[0132] Optionally, the aerosol-generating article has a substantially circular cross-section. Optionally, the aerosol-generating article is in the form of a rod.

[0133] Optionally, the aerosol-generating article has an external diameter of from about 5 millimetres to about 12 millimetres, or from about 6 millimetres to about 12 millimetres, or from about 7 millimetres to about 12 millimetres, or from about 5 millimetres to about 10 millimetres, or from about 6 millimetres to about 10 millimetres, or from about 7 millimetres to about 10 millimetres, or from about 5 millimetres to about 8 millimetres, or from about 6 millimetres to about 8 millimetres, or from about 7 millimetres to about 8 millimetres. Optionally, the aerosolgenerating article has an external diameter of less than 7 millimetres.

[0134] Optionally, the overall RTD of the aerosol-generating article is at least 10 millimetres H2O, or at least 15 millimetres H2O, or at least 20 millimetres H2O, or at least 25 millimetres H2O, or at least 30 millimetres H2O.

[0135] Optionally, the overall RTD of the aerosol-generating article is no more than 70 millimetres H2O, or no more than 60 millimetres H2O, or no more than 55 millimetres H2O, or no more than 50 millimetres H2O, or no more than 45 millimetres H2O.

[0136] Optionally, the overall RTD of the aerosol-generating article is between 10 millimetres H2O and 70 millimetres H2O, or between 15 millimetres H2O and 60 millimetres H2O, orbetween 20 millimetres H2O and 55 millimetres H2O, or between 25 millimetres H2O and 45 millimetres H2O, or between 30 millimetres H2O and 45 millimetres H2O.

[0137] As used herein, the term “aerosol-generating article” refers to an article that is capable of producing and delivering an inhalable aerosol to a consumer.

[0138] As used herein, the term “aerosol-generating substrate” refers to a substrate capable of forming an inhalable aerosol. The aerosol-generating substrate may be capable of releasing volatile compounds to form the inhalable aerosol. Such volatile compounds may be released by heating the aerosol-generating substrate.

[0139] As used herein, the term “adjacent to” refers there being no other elements of the aerosol-generating article located between a first element and a second element the longitudinal direction of the aerosol-generating article.

[0140] As used herein, the term “elongate” refers to an element that has a length dimension that is greater than its width dimension or its diameter dimension, for example twice or more its width dimension or its diameter dimension.

[0141] As used herein, the term “longitudinal” refers to the direction corresponding to the main longitudinal axis of the aerosol-generating article, which extends between the upstream end and the downstream end of the aerosol-generating article. During use, air is drawn through the aerosol-generating article in the longitudinal direction.

[0142] As used herein, the term “transverse” refers to the direction that is perpendicular to the longitudinal direction. Any reference to the “cross-section” of the aerosol-generating article or a component of the aerosol-generating article refers to the transverse cross-section unless stated otherwise.

[0143] As used herein, the terms “upstream” and “downstream” refers to the relative positions of elements, or portions of elements, of the aerosol-generating article in relation to the direction in which the air is transported through the aerosol-generating article during use.

[0144] As used herein, the term “length” refers to the dimension of the, or a component of the, aerosol-generating article in the longitudinal direction. For example, it may be used to denote the dimension of the aerosol-generating substrate or the tubular element in the longitudinal direction.

[0145] As used herein, the term "tubular element" refers to an elongate element defining a lumen or airflow passage in a longitudinal direction thereof. Optionally, the term "tubular" is used to describe a tubular element having a substantially circular transverse cross-sectional shape and defining at least one airflow conduit establishing an uninterrupted fluid communication between an upstream end of the tubular element and a downstream end of the tubular element. However, it will be understood that alternative geometries (for example, alternative transverse cross-sectional shape) of the tubular element may be possible. Forexample, the tubular element may have a circular, oval or elliptical transverse cross-sectional shape.

[0146] As used herein, the term “susceptor element” refers to a material that can convert electromagnetic energy into heat. When located within an alternating magnetic field, eddy currents induced in the susceptor element cause heating of the susceptor element.

[0147] As used herein, the term “convex curvature" describes that the surface of the transverse end wall is curved outwards in a longitudinal direction with respect to the hollow tubular element. As used herein, the term “convex curvature" describes a surface which does not form a flat plane. As used herein, the term “convex curvature" may also describe that a part of the surface of the transverse wall may bulge outwards with respect to the hollow tubular element.

[0148] As used herein, the term “cut filler” is used to describe to a blend of shredded plant material, such as tobacco plant material, including, in particular, one or more of leaf lamina, processed stems and ribs, homogenised plant material.

[0149] As used herein, the term “homogenised plant material” encompasses any plant material formed by the agglomeration of particles of plant. For example, sheets or webs of homogenised tobacco material for the aerosol-generating substrates of the present disclosure may be formed by agglomerating particles of tobacco material obtained by pulverising, grinding or comminuting plant material and optionally one or more of tobacco leaf lamina and tobacco leaf stems. The homogenised plant material may be produced by casting, extrusion, paper making processes or other any other suitable processes known in the art.

[0150] As used herein with reference to the invention, the term “sheet” describes a laminar element having a width and length substantially greater than the thickness thereof.

[0151] As used herein, the term “strand” describes an elongate element of material having a length that is substantially greater than the width and thickness thereof.

[0152] As used herein, the term “film” is used to describe a solid laminar element having a thickness that is less than the width or length thereof. The film may be self-supporting.

[0153] As used herein, the term “cellulose based film-forming agent” is used to describe a cellulosic polymer capable, by itself or in the presence of an auxiliary thickening agent, of forming a continuous film.

[0154] Below, there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0155] Ex1. An aerosol-generating article comprising:

[0156] an aerosol-generating substrate;

[0157] a hollow tubular element; andat least one wrapper circumscribing the hollow tubular element and forming at least one transverse wall adjacent to an end of the hollow tubular element; and

[0158] wherein the, or each of the, at least one transverse wall delimits an aperture for fluid communication between an interior of the hollow tubular element and an exterior of the hollow tubular element.

[0159] Ex2. An aerosol-generating article according to Ex1 , wherein the aerosol-generating article comprises a downstream section extending from the downstream end of the aerosolgenerating substrate to the downstream end of the aerosol-generating article and the hollow tubular element is located within the downstream section.

[0160] Ex3. An aerosol-generating article according to Ex2, wherein the hollow tubular element is located at, or towards, the downstream end of the downstream section or the aerosolgenerating article.

[0161] Ex4. An aerosol-generating article according to Ex1 or Ex2, wherein the hollow tubular element has a length equal to or greater than 95 percent of a length of the downstream section. Ex5. An aerosol-generating article according to any one of Ex2 to Ex4, wherein the downstream section has a length of at least 50 percent of a length of the aerosol-generating article.

[0162] Ex6. An aerosol-generating article according to any one of Ex2 to Ex5, wherein the downstream section has a resistance to draw equal to or less than about 30 mmH20.

[0163] Ex7. An aerosol-generating article according to any one of Ex2 to Ex6, wherein the downstream section does not comprise any component comprising plastic.

[0164] Ex8. An aerosol-generating article according to any one of Ex2 to Ex7, wherein the downstream section does not comprise any component comprising cellulose acetate.

[0165] Ex9. An aerosol-generating article according to any one of Ex2 to Ex8, wherein any element located within the downstream section is made from paper or cardboard.

[0166] Ex10. An aerosol-generating article according to any one of Ex1 to Ex9, wherein the hollow tubular element defines an inner cavity extending from an upstream end of the hollow tubular element to a downstream end of the hollow tubular element and wherein the inner cavity has a constant diameter along the entire length of the hollow tubular element.

[0167] Ex11. An aerosol-generating article according to any one of Ex1 to Ex10, wherein the hollow tubular element comprises a tubular peripheral wall extending from an upstream end of the hollow tubular element to a downstream end of the hollow tubular element and wherein the tubular peripheral wall has a radial thickness of between 200 micrometres and 700 micrometres.

[0168] Ex12. An aerosol-generating article according to any one of Ex1 to Ex11 , wherein the hollow tubular element comprises equal to or greater than 90 percent by weight of biodegradable material.Ex13. An aerosol-generating article according to any one of Ex1 to Ex12, wherein the hollow tubular element is a spirally wound tube.

[0169] Ex14. An aerosol-generating article according to any one of Ex1 to Ex12, wherein the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, formed into a tube forming an overlapping region in which opposing longitudinal ends of the sheet of material overlap.

[0170] Ex15. An aerosol-generating article according to any one of Ex1 to Ex14, wherein the hollow tubular element comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 50 grams per square metre and 400 grams per square metre.

[0171] Ex16. An aerosol-generating article according to any one of Ex1 to Ex15, wherein the hollow tubular element has a length of equal to or greater than 40 percent of a length of the aerosolgenerating article.

[0172] Ex17. An aerosol-generating article according to any one of Ex1 to Ex17, wherein the at least one transverse wall comprises a downstream transverse wall adjacent to a downstream end of the hollow tubular element.

[0173] Ex18. An aerosol-generating article according to Ex17, wherein the downstream transverse wall abuts the downstream end of the hollow tubular element.

[0174] Ex19. An aerosol-generating article according to Ex17 or Ex18, wherein the hollow tubular element is located downstream of the aerosol-generating substrate and wherein the downstream transverse wall is located at, or adjacent to, the downstream end of the aerosolgenerating article.

[0175] Ex20. An aerosol-generating article according to Ex19, wherein the aperture delimited by the downstream transverse wall forms an air outlet of the aerosol-generating article.

[0176] Ex21. An aerosol-generating article according to any one of Ex1 to Ex20, wherein the at least one transverse wall comprises an upstream transverse wall adjacent to an upstream end of the hollow tubular element.

[0177] Ex22. An aerosol-generating article according to Ex21 , wherein the upstream transverse wall abuts the upstream end of the hollow tubular element.

[0178] Ex23. An aerosol-generating article according to Ex21 or Ex22, wherein the hollow tubular element is located downstream of the aerosol-generating substrate and wherein the upstream transverse wall is adjacent to a downstream end of the aerosol-generating substrate.

[0179] Ex24. An aerosol-generating article according to Ex23, wherein the upstream transverse wall abuts the downstream end of the aerosol-generating substrate.

[0180] Ex25. An aerosol-generating article according to any one of Ex1 to Ex24, wherein the, each of the, or any of the, at least one wrapper comprises a folded end portion forming the at least one transverse wall.Ex26. An aerosol-generating article according to any one of Ex1 to Ex24, wherein the, each of the, or one or more of the, at least one transverse wall forms an inward flange.

[0181] Ex27. An aerosol-generating article according to any one of Ex1 to Ex26, wherein the, each of the, or one or more of the, at least one transverse wall has a convex curvature.

[0182] Ex28. An aerosol-generating article according to Ex27, wherein a portion of the, each of the, or one or more of the, at least one transverse wall having a convex curvature is shaped to extend into, or towards, the interior of the hollow tubular element, such as the inner cavity of the hollow tubular element

[0183] Ex29. An aerosol-generating article according to Ex27 or Ex28, wherein the, each of the, or one or more of the, at least one transverse end wall having a convex curvature defines an airflow passage having a diameter that increases in a longitudinal direction away from the longitudinal centre of the hollow tubular element.

[0184] Ex30. An aerosol-generating article according to Ex1 to Ex29, wherein the aperture delimited by the, each of the, or one or more of the, at least one transverse wall is in a radially central position the respective transverse wall.

[0185] Ex31. An aerosol-generating article according to Ex1 to Ex30, wherein the aperture delimited by the, each of the, or one or more of the, has a diameter equal to or greater than 40 percent of a diameter of an interior of the hollow tubular element.

[0186] Ex32. An aerosol-generating article according to Ex1 to Ex31, wherein the at least one wrapper comprises a wrapper forming a downstream transverse wall adjacent to the downstream end of the hollow tubular element.

[0187] Ex33. An aerosol-generating article according to Ex1 to Ex32, wherein the at least one wrapper comprises, or consist of, a first wrapper forming the downstream transverse wall adjacent to the downstream end of the hollow tubular element and a second wrapper forming the upstream end wall adjacent to the upstream end of the hollow tubular element. Optionally, the first wrapper is in physical contact with the second wrapper.

[0188] Ex34. An aerosol-generating article according to Ex1 to Ex33, wherein the hollow tubular element is downstream of the aerosol-generating substrate and the at least one wrapper comprises a wrapper forming the downstream transverse wall adjacent to the downstream end of the hollow tubular element, wherein the wrapper is an outer wrapper defining an outer surface of the aerosol-generating article.

[0189] Ex35. An aerosol-generating article according to Ex34, wherein the outer wrapper further circumscribes at least a portion of the length of the aerosol-generating substrate.

[0190] Ex36. An aerosol-generating article according to Ex34 or Ex35, wherein the outer wrapper extends from the downstream end of the aerosol-generating article to an upstream end of the aerosol-generating article.Ex37. An aerosol-generating article according to Ex1 to Ex36, wherein the, each of the, or one or more of the, at least one wrapper comprises a sheet of material, preferably a sheet of cellulosic material, having a grammage of between 40 grams per square metre and 150 grams per square metre.

[0191] Ex38. An aerosol-generating article according to Ex1 to Ex37, wherein the, or each of the, at least one wrapper comprises a sheet of material having a first grammage, or first plurality of grammages, and the hollow tubular element comprises a sheet of material having a second grammage, wherein the second grammage is greater than the first grammage or the maximum grammage in the first plurality of grammages.

[0192] Ex39. An aerosol-generating article according to Ex1 to Ex38, wherein the, each of the, or one or more of the, at least one wrapper has a thickness of between 100 micrometres and 400 micrometres.

[0193] Ex40. An aerosol-generating article according to Ex1 to Ex39, wherein the, or each of the, at least one wrapper is formed from a sheet of material having a first thickness, or first plurality of thicknesses, and the hollow tubular element is formed from a sheet of material having a second thickness, wherein the second thickness is greater than the first thickness or the maximum thickness in the first plurality of thicknesses.

[0194] Ex41. An aerosol-generating article according to Ex1 to Ex40, wherein the aerosolgenerating substrate is in the form of an aerosol-generating film comprising a cellulosic based film-forming agent, nicotine and the aerosol former.

[0195] Ex42. An aerosol-generating article according to Ex41, wherein the aerosol-generating film further comprise a cellulose based strengthening agent.

[0196] Ex43. An aerosol-generating article according to Ex41 or Ex42, wherein the aerosolgenerating film further comprises water, preferably 30 percent by weight of less of water. Ex44. An aerosol-generating article according to any one of Ex41 to Ex43, wherein the aerosol-generating film is a substantially tobacco-free aerosol-generating film.

[0197] Ex45. An aerosol-generating article according to any one of Ex1 to Ex44, wherein the aerosol-generating article comprises a susceptor element located in thermal contact with the aerosol-generating substrate.

[0198] Ex46. An aerosol-generating article according to Ex45, wherein the susceptor element is positioned in a radially central position within the aerosol-generating substrate, and extends along the longitudinal axis of the aerosol-generating substate.

[0199] Examples will now be further described with reference to the figures in which:

[0200] Figure 1 depicts a schematic cross-sectional view of an aerosol-generating article in accordance with a first embodiment of the present disclosure;Figure 2 depicts a schematic cross-sectional view of an aerosol-generating article in accordance with a second embodiment of the present disclosure;

[0201] Figure 3 depicts a schematic cross-sectional view of an aerosol-generating article in accordance with a third embodiment of the present disclosure; and

[0202] Figures 4 to 6 depict a perspective view of a method of manufacturing a wrapped hollow tubular element in accordance with the present disclosure.

[0203] Figure 1 depicts an aerosol-generating article 100 according to a first embodiment. The aerosol-generating article 100 extends from an upstream end to a downstream end and is in the form of a cylindrical rod. The aerosol-generating article 100 has a length of about 70 millimetres and a diameter of about 7.6 millimetres.

[0204] The aerosol-generating article 100 comprises an aerosol-generating substrate 20 located at the upstream end of the aerosol-generating article 100, a hollow tubular element 30, and a wrapper 40 circumscribing a length of the hollow tubular element 30. An outer wrapper 10 extends from the upstream end of the aerosol-generating article 100 to the downstream end of the aerosol-generating article 100 and circumscribes aerosol-generating substrate 20, the wrapper 40 and the hollow tubular element 30. The outer wrapper 10 is cigarette paper having a grammage of about 40 grams per square metre and a thickness of about 300 micrometres.

[0205] The aerosol-generating substrate 20 comprises a crimped and gathered sheet of homogenised tobacco material having a plurality of ridges or corrugations extending substantially parallel to the longitudinal axis of the rod. The crimped and gathered sheet of homogenised tobacco material extends across substantially the entire transverse cross-sectional area of the aerosol-generating article 100. The aerosol-generating substrate 20 comprises an aerosol former, namely glycerol, and has an aerosol former content of about 10 percent on a dry weight basis. The aerosol-generating substrate 20 has a length of about 14 millimetres. The aerosol-generating substrate 20 is a substantially cylindrical rod having a diameter of about 7 millimetres.

[0206] The hollow tubular element 30 has a length of about 55.7 millimetres and comprises a tubular peripheral wall extending from the upstream end of the hollow tubular element 30 to the downstream end of the hollow tubular element 30. The hollow tubular element 30, and in particular the tubular peripheral wall of the hollow tubular element 30, is made from paper having a grammage of about 100 grams per square metre. The tubular peripheral wall defines an outer diameter of the hollow tubular element 30 and an inner diameter of the hollow tubular element 30. The outer diameter is about 6.4 millimetres and is constant along the length of the hollow tubular element 30. The inner diameter is about 5.6 millimetres and is constant along the length of the hollow tubular element 30. Therefore, the tubular peripheral wall has athickness of about 400 micrometres. The hollow tubular element 30 defines an inner cavity 32 extending from an upstream end of the hollow tubular element 30 to the downstream end of the hollow tubular element 30. The internal cavity 32 is circumscribed by the tubular peripheral wall and is substantially empty, and so substantially unrestricted airflow is enabled along the inner cavity 32.

[0207] The wrapper 40 has been flanged at the downstream end of the hollow tubular element 30 and thereby forms a downstream transverse wall 41 adjacent to the downstream end of the hollow tubular element 30. The downstream transverse wall 41 delimits an aperture 42 for fluid communication between the interior of the hollow tubular element 30, namely the cavity 32, and an exterior of the hollow tubular element 30. The downstream transverse wall 41 is located at the downstream end of the aerosol-generating article and the aperture 42 forms an air outlet of the aerosol-generating article 100.

[0208] The aperture 42 has a circular transverse cross-section and is located in a radially central position of the downstream transverse wall 41. The aperture 42 has a diameter of about 3 millimetres. The wrapper 40 is made from paper having a grammage of about 60 grams per square metre and a thickness of about 300 micrometres. The downstream transverse wall 41 is air impermeable and, thus, airflow is forced to flow through the aperture 42 to pass from the interior of the hollow tubular element 30, through the aperture 42, and to exterior of the hollow tubular element 30.

[0209] In use, a heating element from an electrically operated aerosol-generating device is inserted into, or positioned around, the aerosol-generating substrate 20 which causes the aerosol-generating substrate 20 to heat up and release volatile compounds. A consumer draws on the downstream end of the aerosol-generating article 100 causing air to be drawn through the upstream end of the aerosol-generating article 100. The air is then drawn through the aerosol-generating substrate 20 where volatile compounds released from the heated aerosol-generating substrate 20 are entrained in the air drawn through the aerosol-generating article 100. The volatile compounds and air then pass through the inner cavity 32 of the hollow tubular element 30. The volatile compounds and air cool and condense within the hollow tubular element 30 by, in part, releasing heat to the tubular peripheral wall of the hollow tubular element 30. The cooled and condense volatile compounds and air form an aerosol which is drawn through the aperture 42 and inhaled by the consumer.

[0210] Figure 2 depicts an aerosol-generating article 200 according to a second embodiment. The aerosol-generating article 200 extends from an upstream end to a downstream end and is in the form of a cylindrical rod. The aerosol-generating article 200 has a length of about 70 millimetres and a diameter of about 7.6 millimetres.

[0211] The aerosol-generating article 200 comprises a hollow tubular element 30 located downstream of the aerosol-generating substrate 20. The hollow tubular element 30 is similarin construction to the wrapped hollow tubular element 30 of the first embodiment. In the second embodiment, the wrapper 40 has been flanged at both the downstream end and the upstream end of the hollow tubular element 30 and thereby forms a downstream transverse wall 41 adjacent the downstream end of the hollow tubular element 30 and an upstream transverse wall 43 adjacent the upstream end of the hollow tubular element 30. The upstream transverse wall 43 delimits an aperture 44 for fluid communication between the interior of the hollow tubular element 30, namely the cavity 32, and an exterior of the hollow tubular element 30. Similarly, the downstream transverse wall 41 delimits an aperture 42 for fluid communication between the interior of the hollow tubular element 30, namely the cavity 32, and an exterior of the hollow tubular element 30. The upstream transverse wall 43 abuts the downstream end of aerosol-generating substrate 20 and the downstream transverse wall 41 is located at the downstream end of the aerosol-generating article 200.

[0212] An elongate susceptor element 50 is positioned within the aerosol-generating substrate 20. In more detail, the elongate susceptor element 50 is arranged substantially longitudinally within the aerosol-generating substrate 20, such as to be approximately parallel to the longitudinal axis of the aerosol-generating substrate 20. Moreover, the elongate susceptor element 50 is located in a radially central position within the aerosol-generating substrate 20 and extends effectively along the longitudinal axis of the aerosol-generating substrate 20. The susceptor element 50 extends all the way from an upstream end to a downstream end of the aerosol-generating substrate 20. In effect, the susceptor element 50 has substantially the same length as the aerosol-generating substrate 20. The susceptor element 50 is provided in the form of a strip and has a length of about 9 millimetres, a thickness of about 60 micrometres, and a width of about 4 millimetres.

[0213] The aerosol-generating article 200 comprises a front plug 60 located immediately upstream of the aerosol-generating substrate 20. The downstream end of the front plug 80 abuts the upstream end of the aerosol-generating substrate 20. This advantageously prevents the susceptor element 50 from being dislodged. Further, this ensures that the consumer cannot accidentally contact the heated susceptor element 50 after use.

[0214] The front plug 60 is provided in the form of a cylindrical plug of cellulose acetate circumscribed by a stiff wrapper. The front plug 60 has a length of about 5 millimetres and an RTD of about 30 millimetres H2O.

[0215] The aerosol-generating article 200 comprises a ventilation zone 70 provided at a location along the hollow tubular element 30. In more detail, the ventilation zone 70 is provided at about 25 millimetres from the upstream end of the hollow tubular element 30 and comprises a plurality of perforations through the outer wrapper 10, the wrapper 40 and the hollow tubular element 30. The ventilation level of the aerosol-generating article 200 is about 40 percent.Figure 3 depicts an aerosol-generating article 300 according to a third embodiment. The aerosol-generating article 300 extends from an upstream end to a downstream end and is in the form of a cylindrical rod. The aerosol-generating article 400 has a length of about 70 millimetres and a diameter of about 7.6 millimetres.

[0216] The aerosol-generating article 300 comprises an aerosol-generating substrate 20 located at the upstream end of the aerosol-generating article 100 and a hollow tubular element 30 located towards the downstream end of the aerosol-generating article 300. An outer wrapper 10 extends from the upstream end of the aerosol-generating article 100 to the downstream end of the aerosol-generating article 100 and circumscribes the aerosolgenerating substrate 20 and the hollow tubular element 30. The outer wrapper 10 is paper having a grammage of about 40 grams per square metre and a thickness of about 300 micrometres.

[0217] The aerosol-generating substrate 20 comprises a crimped and gathered sheet of homogenised tobacco material having a plurality of ridges or corrugations extending substantially parallel to the longitudinal axis of the rod. The crimped and gathered sheet of homogenised tobacco material extends across substantially the entire transverse cross-sectional area of the aerosol-generating article 300. The aerosol-generating substrate 20 comprises an aerosol former, namely glycerol, and has an aerosol former content of about 10 percent on a dry weight basis. The aerosol-generating substrate 20 has a length of about 13.7 millimetres. The aerosol-generating substrate 20 is substantially cylindrical and has a diameter of about 7 millimetres.

[0218] The hollow tubular element 30 has a length of about 56 millimetres and comprises a tubular peripheral wall extending from the upstream end of the hollow tubular element 30 to the downstream end of the hollow tubular element 30. The hollow tubular element 30, and in particular the tubular peripheral wall of the hollow tubular element 30, is made from paper having a grammage of about 100 grams per square metre. The tubular peripheral wall defines an outer diameter of the hollow tubular element 30 and an inner diameter of the hollow tubular element 30. The outer diameter is about 7 millimetres and is constant along the length of the hollow tubular element 30. The inner diameter is about 6.2 millimetres and is constant along the length of the hollow tubular element 30. Therefore, the tubular peripheral wall has a thickness of about 400 micrometres. The hollow tubular element 30 defines an inner cavity 32 extending from an upstream end of the hollow tubular element 30 to the downstream end of the hollow tubular element 30. The inner cavity 32 is circumscribed by the tubular peripheral wall and is substantially empty, and so substantially unrestricted airflow is enabled along the inner cavity 32.

[0219] The outer wrapper 10 has been flanged at the downstream end of the hollow tubular element 30 and thereby forms a downstream transverse wall 11 adjacent the downstream endof the hollow tubular element 30. The downstream transverse wall 11 is located at the downstream end of the aerosol-generating article 300. The downstream transverse wall 11 delimits an aperture 12 for fluid communication between the interior of the hollow tubular element 30, namely the cavity 32, and an exterior of the hollow tubular element 30.

[0220] The aperture 12 has a circular transverse cross-section and is located in a radially central position of the downstream transverse wall 11. The aperture 12 has a diameter of about 3 millimetres. The outer wrapper 10 is made from paper having a grammage of about 60 grams per square metre and a thickness of about 300 micrometres.

[0221] Figures 4 to 6 depict a method of manufacturing a wrapped hollow tubular element. The paper wrapper sheet 40 is arranged so that a portion 46 of the length of the paper wrapper sheet 40 extends beyond the end of the hollow tubular element 30. Opposing longitudinal ends 47, 48 of the paper wrapper sheet 40 are overlapped and bonded together, such that the paper wrapper sheet 40 circumscribes at least a portion of the length of the hollow tubular element 30, thereby forming the intermediate arrangement of Figure 5.

[0222] To form the transverse end wall 41 seen in Figure 6, a folding force is applied to the portion 46 of the length of the paper wrapper sheet 40 to bend it about a fold point 2. The folding force deflects the portion 46 inwards relative to the hollow tubular element 30 (as indicated by the dashed curved arrows in Figure 5) and towards the end of the hollow tubular element 30. The folding force continues to be applied until the portion 46 has been folded by an angle of greater than 90 degrees, as measured relative to the peripheral tubular wall of the hollow tubular element. The folding force is then released. The inherent resilient properties of the paper wrapper sheet 40 will cause portion 46 to partially revert back along its folding path, such that the portion 46 reaches a position in which it extends substantially transverse to the longitudinal direction of the hollow tubular element 30. This position is illustrated by Figure 6. The length of the portion 46 of the paper wrapper sheet 40 is such that transverse wall 41 defines an aperture 46.

[0223] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about". Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein. In this context, therefore, a number A is understood as A ± 5% of A.

Claims

CLAIMS1. An aerosol-generating article comprising:an aerosol-generating substrate;a hollow tubular element; andat least one wrapper circumscribing the hollow tubular element and forming at least one transverse wall adjacent to an end of the hollow tubular element; andwherein the, or each of the, at least one transverse wall delimits an aperture for fluid communication between an interior of the hollow tubular element and an exterior of the hollow tubular element.

2. An aerosol-generating article according to claim 1, wherein the aerosol-generating article comprises a downstream section extending from the downstream end of the aerosolgenerating substrate to the downstream end of the aerosol-generating article and the hollow tubular element is located within the downstream section.

3. An aerosol-generating article according to claim 2, wherein the hollow tubular element has a length equal to or greater than 95 percent of a length of the downstream section.

4. An aerosol-generating article according to claim 2 or 3, wherein any element located within the downstream section is made from paper or cardboard.

5. An aerosol-generating article according to any one of claims 1 to 4, wherein the hollow tubular element has a length of equal to or greater than 40 percent of a length of the aerosolgenerating article.

6. An aerosol-generating article according to any one of claims 1 to 5, wherein the at least one transverse wall comprises a downstream transverse wall adjacent to a downstream end of the hollow tubular element.

7. An aerosol-generating article according to any one of claims 1 to 6, wherein the, each of the, or any of the, at least one wrapper comprises a folded end portion forming the at least one transverse wall.

8. An aerosol-generating article according to any one of claims 1 to 7, wherein the, each of the, or one or more of the, at least one transverse wall has a convex curvature and wherein a portion of the, each of the, or one or more of the, at least one transverse wall having aconvex curvature is shaped to extend into, or towards, the interior of the hollow tubular element.

9. An aerosol-generating article according to any one of claims 1 to 8, wherein the aperture delimited by the, each of the, or one or more of the, at least one transverse wall has a diameter equal to or greater than 40 percent of a diameter of the interior of the hollow tubular element.

10. An aerosol-generating article according to any one of claims 1 to 9, wherein the hollow tubular element is located downstream of the aerosol-generating substrate and the at least one wrapper comprises a wrapper forming the downstream transverse wall adjacent to the downstream end of the hollow tubular element, wherein the wrapper is an outer wrapper defining an outer surface of the aerosol-generating article.

11. An aerosol-generating article according to claim 10, wherein the outer wrapper further circumscribes at least a portion of the length of the aerosol-generating substrate.

12. An aerosol-generating article according to any one of claims 1 to 11, wherein the, or each of the, at least one wrapper comprises a sheet of material having a first grammage, or first plurality of grammages, and the hollow tubular element comprises a sheet of material having a second grammage, wherein the second grammage is greater than the first grammage or the maximum grammage in the first plurality of grammages.

13. An aerosol-generating article according to any one of claims 1 to 12, wherein the, or each of the, at least one wrapper is formed from a sheet of material having a first thickness, or first plurality of thicknesses, and the hollow tubular element is formed from a sheet of material having a second thickness, wherein the second thickness is greater than the first thickness or the maximum thickness in the first plurality of thicknesses.

14. An aerosol-generating article according to any one of claims 1 to 13, wherein the aerosol-generating substrate is in the form of an aerosol-generating film comprising a cellulosic based film-forming agent, nicotine and the aerosol former.

15. An aerosol-generating article according to claim 14, wherein the aerosol-generating film is a substantially tobacco-free aerosol-generating film.

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