Aerosol generating article having a hollow tubular element

The aerosol generating article with a dual-tubular structure addresses nicotine delivery and cooling challenges, enhancing usability and sustainability through a support and aerosol cooling element design using paper-based materials.

JP2026510564APending Publication Date: 2026-04-08PHILIP MORRIS PRODUCTS SA
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-02-29
Publication Date
2026-04-08

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Abstract

Aerosol generating article (10) for generating an inhalable aerosol upon heating, comprising: a rod (12) of an aerosol generating substrate; a support element (22) downstream of the rod (12) of the aerosol generating substrate, comprising a first hollow tubular element (26) having an inner diameter D1 and defining a longitudinal cavity (28) that provides an unrestricted flow channel; and an aerosol cooling element (24) downstream of the support element (22), comprising a second hollow tubular element (34) having an inner diameter D2 of at least 6 mm and defining a longitudinal cavity (36) that provides an unrestricted flow channel. The ratio of the inner diameter D2 of the second hollow tubular element (34) to the inner diameter D1 of the first hollow tubular element (26) is at least 1.8.
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Description

Technical Field

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

Background Art

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

[0003] Numerous prior art documents disclose aerosol-generating devices for consuming aerosol-generating articles. Such devices include, for example, electrically heated aerosol-generating devices in which an aerosol is generated by heat transfer from one or more electrical heater elements of the aerosol-generating device to the aerosol-generating substrate of the heated aerosol-generating article. For example, an electrically heated aerosol-generating device has been proposed that includes an internal heater blade adapted to be inserted into an aerosol-generating substrate. The use of aerosol-generating articles in combination with an external heating system is also known. For example, WO2020 / 115151 describes the provision of one or more heating elements arranged around the perimeter of an aerosol-generating article when the aerosol-generating article is received within a cavity of an aerosol-generating device. Alternatively, an inductively heatable aerosol-generating article comprising an aerosol-generating substrate and a susceptor disposed within the aerosol-generating substrate has been proposed by International Publication No. 2015 / 176898.

Summary of the Invention

[0004] Aerosol-generating articles in which the tobacco-containing substrate is heated rather than burned present numerous challenges not seen in conventional smoking articles. Firstly, the tobacco-containing substrate is typically heated to a significantly lower temperature compared to the temperature reached by the pre-burning portion of a conventional cigarette. This can affect nicotine release from the tobacco-containing substrate and nicotine delivery to the consumer. At the same time, if the heating temperature is increased in an attempt to promote nicotine delivery, the resulting aerosol typically needs to be cooled more widely and rapidly before reaching the consumer. However, technical solutions commonly used in conventional smoking articles to cool the mainstream smoke, such as providing a highly filtration-efficient segment at the mouth-end of the cigarette, may have undesirable effects in aerosol-generating articles in which the tobacco-containing substrate is heated rather than burned, as this can reduce nicotine delivery. Consequently, it is desirable to provide novel aerosol-generating articles that can consistently ensure satisfactory aerosol delivery to the consumer.

[0005] Furthermore, there is a general need for aerosol generating articles that are easier to use and have improved practicality. For example, it is desirable to provide an aerosol generating article that can be easily inserted into the heating cavity of an aerosol generating device, and at the same time be held securely within the heating cavity so as not to slip out during use.

[0006] To minimize the environmental impact of used goods, it is even more desirable to provide aerosol-generating goods that can be manufactured using more sustainable materials. [Brief explanation of the drawing]

[0007] [Figure 1] A schematic side cross-sectional view of the aerosol generating article according to the present invention is shown. [Modes for carrying out the invention]

[0008] This disclosure relates to an aerosol generating article. The aerosol generating article may comprise a rod of an aerosol generating substrate. The aerosol generating article may further comprise a support element downstream of the rod of the aerosol generating substrate. The support element may comprise a first hollow tubular element having an inner diameter D1 and defining a cavity in the longitudinal direction that provides an unrestricted flow channel. The aerosol generating article may further comprise an aerosol cooling element downstream of the support element. The aerosol cooling element may comprise a second hollow tubular element having an inner diameter D2 of at least 6 mm and defining a cavity in the longitudinal direction that provides an unrestricted flow channel. The ratio of the inner diameter D2 of the second hollow tubular element to the inner diameter D1 of the first hollow tubular element may be at least 1.8.

[0009] According to the present invention, an aerosol generating article is provided for generating an inhalable aerosol upon heating, the aerosol generating article comprising: a rod of an aerosol generating substrate; a support element downstream of the rod of the aerosol generating substrate, the support element comprising a first hollow tubular element having an inner diameter D1 and defining a cavity in the longitudinal direction that provides an unrestricted flow channel; and an aerosol cooling element downstream of the support element, the aerosol cooling element comprising a second hollow tubular element having an inner diameter D2 of at least 6 mm and defining a cavity in the longitudinal direction that provides an unrestricted flow channel. According to the present invention, the ratio of the inner diameter D2 of the second hollow tubular element to the inner diameter D1 of the first hollow tubular element is at least 1.8.

[0010] As used herein, the term "aerosol-generating article" is used herein to refer to an article comprising an aerosol-generating substrate that is heated in order to generate and deliver an inhalable aerosol to a consumer. As used herein, the term "aerosol-generating substrate" means a substrate that has the ability to release volatile compounds upon heating in order to generate an aerosol.

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

[0012] As used herein in connection with the present invention, the term "rod" is used to refer to a substantially elongated element, preferably a cylindrical element having a substantially circular, oval, or elliptical cross-section.

[0013] As used herein, the term “longitudinal axis” refers to the direction corresponding to the main longitudinal axis of the aerosol generating article, extending between the upstream and downstream ends of the aerosol generating article. As used herein, the terms “upstream” and “downstream” indicate the relative position of an element (or part of an element) of the aerosol generating article with respect to the direction in which aerosols are transported through the aerosol generating article during use.

[0014] During use, air is drawn through the aerosol-generating article in the longitudinal direction. The term "transverse direction" refers to the direction perpendicular to the longitudinal axis. Any reference to the "cross section" of the aerosol-generating article or its components refers to the transverse section unless otherwise specified.

[0015] The term "length" refers to the dimensions of the components of an aerosol-generating article in the longitudinal direction. For example, it may be used to refer to the dimensions of a rod or downstream section in the longitudinal direction.

[0016] As used herein, the term “hollow tubular element” refers to a generally elongated element that defines a lumen or airflow passage along its longitudinal axis. The “inner diameter” of a hollow tubular element corresponds to the diameter of the airflow passage.

[0017] In the context of the present invention, each hollow tubular element provides an unrestricted flow channel. This means that the hollow tubular element provides a negligible level of drawdown resistance (RTD). The term “negligible level of RTD” is used to describe an RTD of less than 1 mmH2O per 10 mm of length of the hollow tubular element, preferably less than 0.4 mmH2O per 10 mm of length of the hollow tubular element, and more preferably less than 0.1 mmH2O per 10 mm of length of the hollow tubular element.

[0018] Unless otherwise specified, the draw resistance (RTD) of a component or aerosol-generating article shall be measured in accordance with ISO 6565-2015. RTD refers to the pressure required to pump air through the entire length of the component. The terms “pressure drop” or “draw resistance” for a component or article may also refer to “resistance to draw.” Such terms generally refer to measurements in accordance with ISO 6565-2015, performed successfully under a test of a volumetric flow rate of 17.5 ml / s at the output or downstream end of the measured component, at a temperature of 22 degrees Celsius, a pressure of 101 kPa (approximately 760 Torr), and a relative humidity of 60%. The conditions for smoking and the specifications of the smoking machine are presented in ISO standard 3308 (ISO 3308:2000). The atmosphere for adjustment and testing is presented in ISO standard 3402 (ISO 3402:1999).

[0019] The present invention relates to an aerosol generating article having a novel arrangement of hollow tubular elements downstream of the rod of an aerosol generating substrate. In particular, the aerosol generating article of the present invention includes an aerosol cooling element formed from a hollow tubular element (second hollow tubular element) having a relatively high inner diameter. This is combined with an upstream support element, which is also formed from a hollow tubular element (first hollow tubular element) having an inner diameter significantly smaller than the inner diameter of the second hollow tubular element of the aerosol cooling element. This difference in the internal sizes of the first and second hollow tubular elements is reflected by a relatively high ratio of the inner diameter D2 of the second hollow tubular element to the inner diameter D1 of the first hollow tubular element, defined as at least 1.8.

[0020] The relatively large inner diameter of the second hollow tubular element of the aerosol cooling element means that the aerosol cooling element provides a cooling chamber with increased volume. This provides enhanced cooling and nucleation of aerosol particles generated from the substrate upon heating, thereby optimizing aerosol delivery from the aerosol-generating article.

[0021] To provide a relatively large inner diameter to the second hollow tubular element, the wall thickness of the second hollow tubular element is typically relatively thin. As the inner diameter increases, the internal surface area of ​​the aerosol cooling element also increases. Both of these factors contribute to improved heat transfer from the inside to the outside of the aerosol cooling element, thereby improving the cooling efficiency within the chamber. Therefore, a specific structure of the aerosol cooling element can provide improved cooling performance.

[0022] Providing aerosol cooling elements with relatively thin wall thicknesses also makes it possible to form aerosol cooling elements from a potentially wider range of materials. In particular, aerosol cooling elements may be formed from paper or cardboard, both of which are lighter and more durable than conventional materials used in aerosol generating articles such as cellulose acetate.

[0023] The upstream support element is formed of a hollow tubular element having a lower inner diameter and thus typically has a greater wall thickness. Thus, the support element is still well adapted to perform its desired function of providing support and stability within the aerosol-generating article downstream of the rod of the aerosol-generating substrate.

[0024] The defined ratio of the inner diameters of the hollow tubular elements forming the support element and the aerosol cooling element means that the inner diameter of the aerosol cooling element is significantly larger than the inner diameter of the support element. This difference between the inner diameters (and thus the cross-sectional area of each flow channel) achieves a controlled expansion of the aerosol, which reduces the velocity of the aerosol as it passes from the support element to the aerosol cooling element. This increases the time the aerosol remains within the aerosol cooling element, and as a result, further optimizes the cooling and nucleation of the aerosol particles as described above.

[0025] As defined above, in the aerosol-generating article of the present invention, the aerosol cooling element is provided downstream of the support element. The upstream end of the aerosol cooling element preferably abuts against the downstream end of the support element. The downstream end of the aerosol cooling element may coincide with the downstream end of the aerosol-generating article. Alternatively, the aerosol-generating article may comprise one or more additional components downstream of the aerosol cooling element, as described below.

[0026] The aerosol cooling element comprises a second hollow tubular element. Preferably, the aerosol cooling element consists only of the second hollow tubular element. Alternatively, the aerosol cooling element may comprise one or more additional cooling elements.

[0027] The second hollow tubular element of the aerosol cooling element has an inner diameter of at least 6 millimeters, more preferably at least 6.1 millimeters, more preferably at least 6.2 millimeters, more preferably at least 6.3 millimeters, more preferably at least 6.4 millimeters, more preferably at least 6.5 millimeters, more preferably at least 6.6 millimeters, more preferably at least 6.7 millimeters, more preferably at least 6.8 millimeters.

[0028] It is preferable that the inner diameter of the second hollow tubular element is less than 7.3 millimeters, more preferably less than 7.25 millimeters, more preferably less than 7.2 millimeters, more preferably less than 7.15 millimeters, more preferably less than 7.1 millimeters, more preferably less than 7 millimeters.

[0029] Therefore, the inner diameter of the second hollow tubular element may be 6 millimeters to 7.3 millimeters, or 6.1 millimeters to 7.25 millimeters, or 6.2 millimeters to 7.2 millimeters, or 6.3 millimeters to 7.2 millimeters, or 6.4 millimeters to 7.15 millimeters, or 6.5 millimeters to 7.15 millimeters, or 6.6 millimeters to 7.1 millimeters, or 6.7 millimeters to 7.1 millimeters, or 6.8 millimeters to 7 millimeters.

[0030] The second hollow tubular element preferably has a constant inner diameter along its entire length. However, the inner diameter of the second hollow tubular element may vary along its length. In such a case, the "inner diameter" as referred to herein should be regarded as the average inner diameter over the length of the hollow tubular element.

[0031] Preferably, the outer diameter of the second hollow tubular element is 5 mm to 12 mm, more preferably 6 mm to 10 mm, more preferably 7 mm to 8 mm, and more preferably 7 mm to 7.5 mm. In some embodiments, the outer diameter of the second hollow tubular element may be less than 7 mm, for example, 5 mm to 7 mm or 6 mm to 7 mm.

[0032] The second hollow tubular element preferably has an outer diameter that is approximately equal to the outer diameter of the rod of the aerosol generating substrate and the outer diameter of the aerosol generating article.

[0033] Preferably, the ratio of the inner diameter of the second hollow tubular element to the outer diameter of the second hollow tubular element is at least 0.75, more preferably at least 0.8, more preferably at least 0.85, and more preferably at least 0.9. The ratio of the inner diameter of the second hollow tubular element to the outer diameter of the second hollow tubular element may be up to 0.98.

[0034] The cavity of the second hollow tubular element may have any cross-sectional shape. Preferably, the cavity of the second hollow tubular element has a circular or substantially circular cross-sectional shape.

[0035] The wall thickness of the second hollow tubular element is preferably less than 0.5 mm, more preferably less than 0.45 mm, more preferably less than 0.4 mm, and more preferably less than 0.35 mm. The wall thickness is preferably at least 0.1 mm, more preferably at least 0.15 mm, and more preferably at least 0.2 mm.

[0036] For example, the wall thickness of the second hollow tubular element may be 0.1 mm to 0.5 mm, or 0.15 mm to 0.45 mm, or 0.15 mm to 0.4 mm, or 0.2 mm to 0.4 mm, or 0.2 mm to 0.35 mm. Thus, as described above, the second hollow tubular element has relatively thin walls.

[0037] The second hollow tubular element is preferably formed from a paper-based material such as paper or cardboard. The second hollow tubular element is preferably a paper tube formed from one or more layers of paper. The second hollow tubular element is more preferably a paper tube formed from multiple overlapping layers of paper.

[0038] The second hollow tubular element preferably includes at least two overlapping paper layers, and more preferably at least three overlapping paper layers. The second hollow tubular element preferably includes up to 10 overlapping paper layers, and more preferably up to 5 overlapping paper layers. For example, the second hollow tubular element may include 2 to 10 overlapping paper layers, or 3 to 5 overlapping paper layers. The paper layers may be formed from the same paper material or different paper materials.

[0039] Each paper layer typically extends at least once around the second hollow tubular element, and preferably, each paper layer is wrapped multiple times around the second hollow tubular element to form a wall structure and obtain a desired wall thickness.

[0040] Preferably, multiple overlapping paper layers are spirally wound around the longitudinal axis of a second hollow tubular element. This provides a spirally wound structure similar to the layered structure of conventional paper strings. Hollow tubular elements incorporating the spiral arrangement of layers for use in the present invention can be manufactured using existing straw-making equipment such as the Hauni Straw Maker (HSM) from Hauni Maschinenbau GmbH.

[0041] By using a spirally wound structure, optimal structural strength is provided for the second hollow tubular element, and mechanical strength is increased in all directions compared to similar structures with simple longitudinal packaging.

[0042] Each individual paper layer of the paper tube preferably has a thickness of 30 to 200 microns, more preferably 45 to 150 microns, more preferably 45 to 135 microns, and more preferably 75 to 125 microns.

[0043] The individual paper layers forming the paper tube may have the same thickness as each other. Alternatively, the individual paper layers forming the paper tube may have different thicknesses as each other. For example, the paper tube may be formed of multiple paper layers, each having a thickness within the defined range described above, but with the thickness of the paper layers decreasing from the inner layers to the outer layers. Such an arrangement may be beneficial in the manufacturing process because forming thicker paper layers requires greater force to bend them, and it is easier to add greater strength to the inner layers during manufacturing, for example, by winding the layers around a mandrel.

[0044] For example, the paper tube forming the second hollow tubular element may include one or more layers of the first paper material and one or more layers of the second paper material, wherein the thickness of the second paper material is greater than the thickness of the first paper material. The thickness of the second paper material may be at least 25 microns greater, or at least 30 microns greater, or at least 40 microns greater than the thickness of the first paper material.

[0045] Each individual paper layer of the paper tube preferably has a basis weight of 25 grams / square meter (gsm) to 150 gsm, 30 gsm to 130 gsm, or 35 gsm to 120 gsm.

[0046] The individual paper layers forming the paper tube may have the same basis weight. Alternatively, the individual paper layers forming the paper tube may have different basis weights. For example, the paper tube may be formed from multiple paper layers, each having a basis weight within the defined range, but the basis weight of the paper layers decreases from the inner layers to the outer layers.

[0047] For example, the paper tube forming the second hollow tubular element may include one or more layers of the first paper material and one or more layers of the second paper material, wherein the basis weight of the second paper material is greater than the basis weight of the first paper material. The basis weight of the second paper material may be at least 25 gsm greater, or at least 30 gsm greater, or at least 40 gsm greater than the thickness of the first paper material.

[0048] The paper tube may be formed from layers of paper having the same composition. Alternatively, the paper tube may be formed from layers of paper having different compositions.

[0049] The paper tube preferably includes at least one hydrophobic paper layer. The hydrophobic paper layer is preferably provided as the innermost layer of the paper tube so as to provide the inner surface of the paper tube.

[0050] The term "hydrophobic" refers to a surface that exhibits water-repellent properties. One useful way to determine this is by measuring the water contact angle. The "water contact angle" is the angle at which the liquid / vapor interface contacts a solid surface, and has traditionally been measured through the liquid. The water contact angle quantifies the wettability of a solid surface by a liquid, via Young's equation. Hydrophobicity or the water contact angle can be determined using the TAPPI T558 test method, and the result is expressed as the interfacial contact angle, reported in "degrees," and can range from approximately zero to approximately 180 degrees.

[0051] In a preferred embodiment, the hydrophobic paper layer is a paper layer that includes a paper layer having a water contact angle of about 30 degrees or more, preferably about 35 degrees or more, or about 40 degrees or more, or about 45 degrees or more.

[0052] For example, the hydrophobic paper layer may contain waxes such as PVOH (polyvinyl alcohol), silicone, or paraffin wax. The hydrophobic paper layer may have a hydrophobic coating layer of one of these materials applied to its surface, or the surface of the paper layer may be surface-treated with one of these materials to provide hydrophobicity.

[0053] By providing a hydrophobic layer on the inside of the paper tube, moisture from the aerosol can be prevented from penetrating the tube, and the structural rigidity of the aerosol cooling element can be maintained during use. Furthermore, it is advantageous that friction with the surface of manufacturing equipment such as mandrels can be reduced during production.

[0054] The aerosol cooling element may have a length of 5 to 15 millimeters. Preferably, the aerosol cooling element has a length of at least about 6 millimeters, and more preferably, a length of at least about 7 millimeters. Preferably, the aerosol cooling element has a length of less than about 12 millimeters, more preferably less than about 10 millimeters.

[0055] In some embodiments, the aerosol cooling element has a length of about 5 mm to about 15 mm, preferably about 6 mm to about 15 mm, and more preferably about 7 mm to about 15 mm. In other embodiments, the aerosol cooling element has a length of about 5 mm to about 12 mm, preferably about 6 mm to about 12 mm, and more preferably about 7 mm to about 12 mm. In further embodiments, the aerosol cooling element has a length of about 5 mm to about 10 mm, preferably about 6 mm to about 10 mm, and more preferably about 7 mm to about 10 mm.

[0056] In a particularly preferred embodiment of the present invention, the aerosol cooling element has a length of less than 10 millimeters. For example, in one particularly preferred embodiment, the aerosol cooling element has a length of 8 or 9 millimeters. In such embodiments, the aerosol cooling element is therefore relatively short in length compared to the aerosol cooling elements of prior art aerosol generating articles. The length of the aerosol cooling element can be shortened by optimizing the hollow tubular elements that form the aerosol cooling element in aerosol cooling and nucleation.

[0057] In a preferred embodiment in which the aerosol cooling element consists of a second hollow tubular element, the length of the second hollow tubular element is within the range defined above.

[0058] For example, in some embodiments, the second hollow tubular element has a length of about 5 mm to about 15 mm, preferably about 6 mm to about 15 mm, and more preferably about 7 mm to about 15 mm. In other embodiments, the second hollow tubular element has a length of about 5 mm to about 12 mm, preferably about 6 mm to about 12 mm, and more preferably about 7 mm to about 12 mm. In further embodiments, the second hollow tubular element has a length of about 5 mm to about 10 mm, preferably about 6 mm to about 10 mm, and more preferably about 7 mm to about 10 mm. In a particularly preferred embodiment of the present invention, the second hollow tubular element has a length of less than 10 mm. For example, in one particularly preferred embodiment, the second hollow tubular element has a length of 8 mm or 9 mm.

[0059] Preferably, the ratio of the length of the aerosol cooling element to the total length of the aerosol generating article substrate is at least 0.13, more preferably at least 0.14, and even more preferably at least 0.15. The ratio between the length of the aerosol cooling element and the total length of the aerosol generating article substrate is preferably less than 0.3, more preferably less than 0.25, and even more preferably less than 0.20.

[0060] In some embodiments, the ratio of the length of the aerosol cooling element to the total length of the aerosol generating article is preferably 0.13 to 0.3, more preferably 0.14 to 0.3, and even more preferably 0.15 to 0.3. In other embodiments, the ratio of the length of the aerosol cooling element to the total length of the aerosol generating article is preferably 0.13 to 0.25, more preferably 0.14 to 0.25, and even more preferably 0.15 to 0.25. In further embodiments, the ratio of the length of the aerosol cooling element to the total length of the aerosol generating article is preferably 0.13 to 0.2, more preferably 0.14 to 0.2, and even more preferably 0.15 to 0.2. In a particularly preferred embodiment, the ratio of the length of the aerosol cooling element to the total length of the aerosol generating article is about 0.18.

[0061] The second hollow tubular element may have an internal volume of 150 cubic millimeters to 450 cubic millimeters. Preferably, the second hollow tubular element has an internal volume of at least about 200 cubic millimeters, more preferably at least about 250 cubic millimeters. Preferably, the second hollow tubular element has an internal volume of less than about 400 cubic millimeters, more preferably less than about 350 cubic millimeters.

[0062] In some embodiments, the second hollow tubular element has an internal volume of about 150 cubic millimeters to about 450 cubic millimeters, preferably about 200 cubic millimeters to about 450 cubic millimeters, and more preferably about 250 cubic millimeters to about 450 cubic millimeters. In other embodiments, the second hollow tubular element has an internal volume of about 150 cubic millimeters to about 400 cubic millimeters, preferably about 200 cubic millimeters to about 400 cubic millimeters, and more preferably about 250 cubic millimeters to about 400 cubic millimeters. In further embodiments, the second hollow tubular element has an internal volume of about 150 cubic millimeters to about 350 cubic millimeters, preferably about 200 cubic millimeters to about 350 cubic millimeters, and more preferably about 250 cubic millimeters to about 350 cubic millimeters.

[0063] The aerosol cooling element preferably further comprises a ventilation zone located along a second hollow tubular element. The ventilation zone extends through the wall of the hollow tubular element so that fluid communication is established between a flow channel internally defined by the second hollow tubular element and the external environment. The ventilation zone includes a plurality of perforations through the wall of the second hollow tubular element. The ventilation zone preferably includes at least one circumferential row of perforations. Preferably, each circumferential row of perforations includes 8 to 30 perforations.

[0064] The aerosol-generating article according to the present invention may have a ventilation level of at least 10 percent, preferably at least 15 percent, more preferably at least 20 percent, more preferably at least 25 percent, and more preferably at least 30 percent. The ventilation level may be up to 60 percent, preferably up to 50 percent, more preferably up to 45 percent, and more preferably up to 40 percent. For example, the ventilation level may be 10 percent to 60 percent, or 15 percent to 50 percent, or 20 percent to 45 percent, or 25 percent to 45 percent, or 30 percent to 40 percent. In a particularly preferred embodiment, the aerosol-generating article has a ventilation level of about 35 percent.

[0065] The term "ventilation level" is used throughout this specification to mean the volume ratio of the airflow entering the aerosol-generating article through the ventilation zone (ventilation airflow) to the sum of the aerosol airflow and the ventilation airflow. A higher ventilation level results in a higher degree of dilution of the aerosol flow delivered to the consumer.

[0066] Rapid cooling induced by introducing outside air into the second hollow tubular element through a ventilation zone can be used to favor the advantageous nucleation and growth of aerosol droplets.

[0067] The distance between the ventilation zone and the downstream end of the rod of the aerosol generating substrate is preferably at least 6 millimeters, more preferably at least 7 millimeters, more preferably at least 8 millimeters, more preferably at least 9 millimeters, and more preferably at least 10 millimeters.

[0068] The distance between the ventilation zone and the downstream end of the rod of the aerosol generating substrate is preferably less than 16 millimeters, more preferably less than 15 millimeters, more preferably less than 14 millimeters, more preferably less than 13 millimeters, and more preferably less than 12 millimeters.

[0069] The distance between the ventilation zone and the downstream end of the rod of the aerosol generating substrate may be 6 mm to 16 mm, or 7 mm to 15 mm, or 8 mm to 14 mm, or 9 mm to 13 mm, or 10 mm to 12 mm.

[0070] Positioning the ventilation zone slightly away from the downstream end of the aerosol-generating rod within the aforementioned range has the advantage of generally ensuring that the ventilation zone is immediately outside the heating device when the aerosol-generating article is inserted into the heating device during use. Additionally, it has been found that positioning the ventilation zone slightly away from the downstream end of the aerosol-generating rod within the aforementioned range may advantageously enhance nucleation and aerosol formation and delivery.

[0071] The distance between the ventilation zone and the downstream end of the aerosol-generating article is preferably at least 10 millimeters, more preferably at least 12 millimeters, more preferably at least 14 millimeters, and more preferably at least 16 millimeters.

[0072] The distance between the ventilation zone and the downstream end of the aerosol-generating article is preferably less than 24 millimeters, more preferably less than 22 millimeters, more preferably less than 21 millimeters, and more preferably less than 20 millimeters.

[0073] For example, the distance between the ventilation zone and the downstream end of the aerosol-generating article may be 10 to 24 millimeters, or 12 to 22 millimeters, or 14 to 21 millimeters, or 16 to 20 millimeters. In a particularly preferred embodiment, the distance between the ventilation zone and the downstream end of the aerosol-generating article is about 18 millimeters.

[0074] Positioning the ventilation zone a short distance within the aforementioned range from the downstream end of the aerosol-generating article has the advantage of generally ensuring that when the aerosol-generating article is partially received inside the heating device during use, the portion of the aerosol-generating article extending outside the heating device is long enough for the consumer to comfortably hold the article between their lips. At the same time, it is suggested that if the length of the portion of the aerosol-generating article extending outside the heating device is too long, the aerosol-generating article may become more prone to bending inadvertently and unintentionally, which may impair aerosol delivery or the intended use of the aerosol-generating article in general.

[0075] The aerosol cooling element preferably has a negligible level of RTD. For example, the aerosol cooling element preferably has an RTD of less than 2 mmH2O, more preferably less than 1.5 mmH2O, more preferably less than 1 mmH2O, more preferably less than 0.5 mmH2O, and most preferably about 0 mmH2O.

[0076] As defined above, the aerosol generating article of the present invention comprises a support element downstream of the rod of the aerosol generating substrate. Preferably, the upstream end of the support element abuts against the downstream end of the rod of the aerosol generating substrate. Preferably, the downstream end of the support element abuts against the upstream end of the aerosol cooling element.

[0077] The support element includes a first hollow tubular element. Preferably, the support element includes only the first hollow tubular element.

[0078] Preferably, the first hollow tubular element has an inner diameter of less than 5.5 mm, more preferably less than 5 mm, more preferably less than 4.5 mm, more preferably less than 4 mm, and more preferably less than 3.5 mm.

[0079] The inner diameter of the first hollow tubular element is preferably at least 1.5 mm, more preferably at least 2 mm, more preferably at least 2.5 mm, more preferably at least 2.75 mm, and more preferably at least 3 mm.

[0080] For example, the inner diameter of the first hollow tubular element may be 1.5 mm to 5.5 mm, or 2 mm to 5 mm, or 2.5 mm to 4.5 mm, or 2.75 mm to 4 mm, or 3 mm to 3.5 mm.

[0081] As defined above, according to the present invention, the ratio of the inner diameter of the second hollow tubular element to the inner diameter of the first hollow tubular element is at least 1.8. Therefore, the inner diameter of the second hollow tubular element forming the aerosol cooling element is at least 1.8 times the inner diameter of the first hollow tubular element forming the support element.

[0082] The ratio of the inner diameter of the second hollow tubular element to the inner diameter of the first hollow tubular element is preferably at least 1.85, more preferably at least 1.9, more preferably at least 1.95, more preferably at least 2, more preferably at least 2.05, and more preferably at least 2.1. The ratio of the inner diameter of the second hollow tubular element to the inner diameter of the first hollow tubular element is preferably less than 2.75, more preferably less than 2.6, more preferably less than 2.5, and more preferably less than 2.4.

[0083] The first hollow tubular element preferably has a constant inner diameter along its entire length. However, the inner diameter of the second hollow tubular element may vary along its length. In such cases, the "inner diameter" as referred to herein should be considered as the average inner diameter over the length of the hollow tubular element.

[0084] Preferably, the outer diameter of the first hollow tubular element is 5 mm to 12 mm, more preferably 6 mm to 10 mm, more preferably 7 mm to 8 mm, and more preferably 7 mm to 7.5 mm. In some embodiments, the outer diameter of the first hollow tubular element may be less than 7 mm, for example, 5 mm to 7 mm or 6 mm to 7 mm.

[0085] The first hollow tubular element preferably has an outer diameter that is approximately equal to the outer diameter of the rod of the aerosol generating substrate and the outer diameter of the aerosol generating article.

[0086] The ratio of the inner diameter of the first hollow tubular element to the outer diameter of the first hollow tubular element is preferably at least 0.25, more preferably at least 0.3, more preferably at least 0.35, and more preferably at least 0.4. The ratio of the inner diameter of the first hollow tubular element to the outer diameter of the first hollow tubular element may be up to 0.80.

[0087] The cavity of the first hollow tubular element may have any cross-sectional shape. Preferably, the cavity of the first hollow tubular element has a circular or substantially circular cross-sectional shape.

[0088] The wall thickness of the first hollow tubular element is preferably at least 1 millimeter, more preferably at least 1.5 millimeters, and more preferably at least 2 millimeters. The wall thickness is preferably less than 3.5 millimeters, more preferably less than 3 millimeters, and more preferably less than 2.75 millimeters.

[0089] For example, the wall thickness of the first hollow tubular element may be 1 mm to 3.5 mm, or 1.5 mm to 3 mm, or 2 mm to 2.75 mm.

[0090] The first hollow tubular element may be formed from any suitable material or combination of materials. For example, the first hollow tubular element may be formed from one or more materials selected from the group consisting of cellulose acetate, polyhydroxyalkanoate (PHA) fibers, cardboard, crimped paper such as crimped heat-resistant paper or crimped sulfuric acid paper, and polymer materials such as low-density polyethylene (LDPE). In a preferred embodiment, the first hollow tubular element is a hollow acetate tube formed from cellulose acetate.

[0091] The support element may have a length of 5 to 15 millimeters. Preferably, the support element has a length of at least about 6 millimeters, and more preferably, at least about 7 millimeters. Preferably, the support element has a length of less than about 12 millimeters, and more preferably less than about 10 millimeters.

[0092] In some embodiments, the support element has a length of about 5 mm to about 15 mm, preferably about 6 mm to about 15 mm, and more preferably about 7 mm to about 15 mm. In other embodiments, the support element has a length of about 5 mm to about 12 mm, preferably about 6 mm to about 12 mm, and more preferably about 7 mm to about 12 mm. In further embodiments, the support element has a length of about 5 mm to about 10 mm, preferably about 6 mm to about 10 mm, and more preferably about 7 mm to about 10 mm.

[0093] In a preferred embodiment in which the support element consists of a first hollow tubular element, the length of the first hollow tubular element is within the range defined above.

[0094] For example, in some embodiments, the first hollow tubular element has a length of about 5 mm to about 15 mm, preferably about 6 mm to about 15 mm, and more preferably about 7 mm to about 15 mm. In other embodiments, the first hollow tubular element has a length of about 5 mm to about 12 mm, preferably about 6 mm to about 12 mm, and more preferably about 7 mm to about 12 mm. In further embodiments, the first hollow tubular element has a length of about 5 mm to about 10 mm, preferably about 6 mm to about 10 mm, and more preferably about 7 mm to about 10 mm. In a particularly preferred embodiment of the present invention, the first hollow tubular element has a length of 8 mm or 9 mm.

[0095] Preferably, the ratio of the length of the support element to the total length of the aerosol-generating article is at least 0.13, more preferably at least 0.14, and even more preferably at least 0.15. Preferably, the ratio of the length of the support element to the total length of the aerosol-generating article is less than 0.3, more preferably less than 0.25, and even more preferably less than 0.20.

[0096] In some embodiments, the ratio of the length of the support element to the total length of the aerosol-generating article is preferably 0.13 to 0.3, more preferably 0.14 to 0.3, and even more preferably 0.15 to 0.3. In other embodiments, the ratio of the length of the support element to the total length of the aerosol-generating article is preferably 0.13 to 0.25, more preferably 0.14 to 0.25, and even more preferably 0.15 to 0.25. In further embodiments, the ratio of the length of the support element to the total length of the aerosol-generating article is preferably 0.13 to 0.2, more preferably 0.14 to 0.2, and even more preferably 0.15 to 0.2. In a particularly preferred embodiment, the ratio of the length of the support element to the total length of the aerosol-generating article is 0.18.

[0097] The first hollow tubular element may have an internal volume of 10 cubic millimeters to 200 cubic millimeters. The second hollow tubular element preferably has an internal volume of at least about 20 cubic millimeters, more preferably at least about 50 cubic millimeters. The second hollow tubular element preferably has an internal volume of less than about 150 cubic millimeters, more preferably less than about 90 cubic millimeters.

[0098] In some embodiments, the first hollow tubular element has an internal volume of about 10 cubic millimeters to about 200 cubic millimeters, preferably about 20 cubic millimeters to about 200 cubic millimeters, and more preferably about 50 cubic millimeters to about 200 cubic millimeters. In other embodiments, the first hollow tubular element has an internal volume of about 10 cubic millimeters to about 150 cubic millimeters, preferably about 20 cubic millimeters to about 150 cubic millimeters, and more preferably about 50 cubic millimeters to about 150 cubic millimeters. In further embodiments, the first hollow tubular element has an internal volume of about 10 cubic millimeters to about 90 cubic millimeters, preferably about 20 cubic millimeters to about 90 cubic millimeters, and more preferably about 50 cubic millimeters to about 90 cubic millimeters.

[0099] The ratio of the length of the aerosol cooling element to the length of the support element is preferably at least 0.8, more preferably at least 0.9, more preferably at least 1, more preferably at least 1.1, more preferably at least 1.2, more preferably at least 1.3, more preferably at least 1.4, and more preferably at least 1.5. The ratio of the length of the aerosol cooling element to the length of the support element may be up to 2.2, more preferably up to 2.1, and more preferably up to 2.

[0100] For example, in some embodiments, the ratio of the length of the aerosol cooling element to the length of the support element may be 0.8 to 1. In these embodiments, the aerosol cooling element has a length less than or equal to the length of the support element. In other embodiments, the ratio of the length of the aerosol cooling element to the length of the support element may be 1.1 to 2.2, or 1.2 to 2.1, or 1.3 to 2.1, or 1.4 to 2, or 1.5 to 2.

[0101] The ratio of the internal volume of the aerosol cooling element to the internal volume of the support element is preferably at least 1, more preferably at least 1.5, more preferably at least 2, more preferably at least 2.5, more preferably at least 3, and more preferably at least 3.5. The ratio of the internal volume of the aerosol cooling element to the internal volume of the support element may be up to 20, more preferably up to 17.5, more preferably up to 15, more preferably up to 12.5, more preferably up to 10, and more preferably up to 7.5.

[0102] For example, in some embodiments, the ratio of the internal volume of the aerosol cooling element to the internal volume of the support element may be 1 to 20, or 1.5 to 17.5, or 2 to 15, or 2.5 to 12.5, or 3 to 10, or 3.5 to 7.5.

[0103] The support element preferably has a negligible level of RTD. For example, the support element preferably has an RTD of less than 2 mmH2O, more preferably less than 1.5 mmH2O, more preferably less than 1 mmH2O, more preferably less than 0.5 mmH2O, and most preferably about 0 mmH2O.

[0104] As shown above, the aerosol generating article according to the present invention further comprises a rod of an aerosol generating substrate.

[0105] Preferably, the rod of the aerosol generating substrate has a length of at least 8 millimeters, more preferably at least 9 millimeters, and more preferably at least 10 millimeters. Preferably, the length of the rod of the aerosol generating substrate is less than 16 millimeters, more preferably less than 15 millimeters, and more preferably less than 14 millimeters. For example, the rod of the aerosol generating substrate may have a length of 8 to 16 millimeters, or 9 to 15 millimeters, or 10 to 14 millimeters. In a particularly preferred embodiment, the rod of the aerosol generating substrate has a length of about 12 millimeters.

[0106] The ratio of the length of the rod of the aerosol generating substrate to the total length of the aerosol generating article is preferably at least 0.10, more preferably at least 0.15, more preferably at least 0.20, and more preferably at least 0.25. Preferably, the ratio of the length of the rod of the aerosol generating substrate to the total length of the aerosol generating article is less than 0.50, more preferably less than 0.45, more preferably less than 0.40, and more preferably less than 0.35. For example, the ratio of the length of the rod of the aerosol generating substrate to the total length of the aerosol generating article may be 0.1 to 0.5, or 0.15 to 0.45, or 0.2 to 0.4, or 0.25 to 0.35.

[0107] The rod of the aerosol generating substrate preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol generating article.

[0108] Preferably, the rod of the aerosol generating substrate has an outer diameter of at least 5 mm, more preferably at least 6 mm, and more preferably at least 7 mm. Before inserting the aerosol generating article into the aerosol generating device, the rod of the aerosol generating substrate preferably has an outer diameter of less than 12 mm, more preferably less than 10 mm, and more preferably less than 8 mm. For example, the outer diameter may be 5 mm to 12 mm, or 6 mm to 10 mm, or 7 mm to 8 mm. In a particularly preferred embodiment, the rod of the aerosol generating substrate has an outer diameter of about 7.1 mm.

[0109] The rod of the aerosol generating substrate preferably has a substantially uniform cross-section along its length. Particularly preferably, the rod of the aerosol generating substrate has a substantially circular cross-section before the aerosol generating article is inserted into the aerosol generating device.

[0110] The aerosol generating substrate may be a solid aerosol generating substrate. Suitable types of materials for use in the aerosol generating substrate are described below and include, for example, homogenized tobacco materials such as tobacco cut filler and cast leaf, aerosol generating films, and gel compositions.

[0111] The aerosol generating substrate preferably includes an aerosol forming agent. The aerosol forming agent can be any suitable known compound or mixture of compounds that promotes the formation of a dense and stable aerosol during use. The aerosol forming agent can promote the aerosol's substantial resistance to thermal decomposition at the temperatures typically applied during use of the aerosol generating article. Suitable aerosol forming agents include, for example, polyhydric alcohols (e.g., triethylene glycol, 1,3-butanediol, propylene glycol, glycerin, etc.), esters of polyhydric alcohols (e.g., glycerol mono-, di-, or triacetate, etc.), aliphatic esters of mono-, di-, or polycarboxylic acids (e.g., dimethyl dodecanediol, dimethyl tetradecanediol, etc.), and combinations thereof.

[0112] The aerosol-forming body preferably contains one or more of glycerin and propylene glycol. The aerosol-forming body may consist of glycerin, propylene glycol, or a combination of glycerin and propylene glycol.

[0113] In certain embodiments, the aerosol generating substrate preferably contains at least 5 weight percent of aerosol-forming material on a dry weight basis of the aerosol generating substrate, more preferably at least 10 weight percent on a dry weight basis, and even more preferably at least 15 weight percent on a dry weight basis. In such embodiments, the aerosol generating substrate preferably contains 30 weight percent or less of aerosol-forming material on a dry weight basis of the aerosol generating substrate, more preferably 25 weight percent or less on a dry weight basis, and more preferably 20 weight percent or less on a dry weight basis. For example, the aerosol-forming material content of the aerosol generating substrate may be 5 weight percent to 30 weight percent, or 10 weight percent to 25 weight percent, or about 15 weight percent to about 20 weight percent on a dry weight basis. Therefore, in such embodiments, the aerosol-forming material content is relatively low.

[0114] In other embodiments, the aerosol generating substrate preferably contains at least 40 weight percent of aerosol forming material on a dry weight basis of the aerosol generating substrate, more preferably at least 45 weight percent on a dry weight basis, and more preferably at least 50 weight percent on a dry weight basis. In such embodiments, the aerosol generating substrate preferably contains 80 weight percent or less of aerosol forming material on a dry weight basis of the aerosol generating substrate, more preferably 75 weight percent or less on a dry weight basis, and more preferably 70 weight percent or less on a dry weight basis. For example, the aerosol forming material content of the aerosol generating substrate may be 40 weight percent to 80 weight percent, or 45 weight percent to 75 weight percent, or 50 weight percent to 70 weight percent on a dry weight basis. Therefore, in such embodiments, the aerosol forming material content is relatively high.

[0115] In some preferred embodiments, the aerosol generating substrate includes tobacco material. For example, the aerosol generating substrate may include shredded tobacco material. For example, the shredded tobacco material may be in the form of cut fillers, as will be described in more detail below. Alternatively, the shredded tobacco material may be in the form of shredded sheets of homogenized tobacco material. Preferred homogenized tobacco materials for use in the present invention are described below.

[0116] In the context of this specification, the term “cut filler” is used to refer to a blend of shredded plant material, such as tobacco plant material comprising one or more of the following: leaf laminas, processed stems and veins, and homogenized plant material.

[0117] Cut fillers may also include other cut pieces, filler tobacco, or outer covering.

[0118] Preferably, the cut filler contains at least 25 percent of plant leaf blades, more preferably at least 50 percent of plant leaf blades, even more preferably at least 75 percent of plant leaf blades, and most preferably at least 90 percent of plant leaf blades. Preferably, the plant material is one of tobacco, mint, tea, and clove. Most preferably, the plant material is tobacco. However, the present invention is equally applicable to other plant materials that have the ability to release substances when heated and subsequently form aerosols.

[0119] The cut filler suitable for use in the present invention may generally be similar to the cut filler used in conventional smoking articles. The cutting width of the cut filler may preferably be 0.3 mm to 2.0 mm, or 0.5 mm to 1.2 mm, or 0.6 mm to 0.9 mm.

[0120] Preferably, the strands have a length of about 10 mm to about 40 mm, and the strands are then arranged to form a rod of aerosol generating substrate.

[0121] In a preferred embodiment, the weight of the cut filler is 25 to 150 milligrams, preferably 30 to 125 milligrams, and more preferably 40 to 100 milligrams. This amount of cut filler is typically sufficient material for aerosol formation during early fuming.

[0122] The cut filler is preferably immersed in an aerosol-forming material. Immersion of the cut filler can be carried out by spraying or other suitable application methods. The aerosol-forming material can be added to the blend during the preparation of the cut filler. For example, the aerosol-forming material may be applied directly to the blend in the conditioning casing cylinder (DCCC). Conventional machinery can be used to apply the aerosol-forming material to the cut filler. Suitable aerosol-forming materials are presented above.

[0123] The aerosol-forming body in the cut filler preferably contains one or more of glycerol and propylene glycol. The aerosol-forming body may consist of glycerol, propylene glycol, or a combination of glycerol and propylene glycol.

[0124] In other preferred embodiments, the aerosol generating substrate comprises homogenized plant material, preferably homogenized tobacco material.

[0125] As used herein, the term “homogenized plant material” encompasses any plant material formed by the aggregation of plant particles. For example, a sheet or web made of homogenized tobacco material for an aerosol generating substrate of the present invention may be formed by aggregating particles of tobacco material obtained by crushing, grinding, or pulverizing a plant material and optionally one or more thin layers of tobacco leaves and / or tobacco leaf stems. Homogenized plant material can be produced by molding, extrusion, papermaking processes, or any other suitable process known in the art.

[0126] Homogenized plant material can be provided in any preferred form.

[0127] In some embodiments, the homogenized plant material may be in the form of one or more sheets. As used herein in relation to the present invention, the term “sheet” refers to a layered element having a width and length substantially greater than its thickness.

[0128] The homogenized plant material may be in the form of multiple pellets or granules.

[0129] Homogenized plant material may be in the form of multiple strands, flakes, or shreds. As used herein, the term “strand” describes an elongated element of the material having a length substantially greater than its width and thickness. The term “strand” should be considered to encompass any other homogenized plant material having flakes, fragments, and similar forms. Strands of homogenized plant material may be formed from a sheet of homogenized plant material, for example, by cutting or shredding, or by other means, such as extrusion.

[0130] The aerosol-forming content of the homogenized tobacco material is preferably within the range defined above for aerosol-generating substrates having a relatively low aerosol-forming content.

[0131] In other preferred embodiments, the aerosol generating substrate is in the form of an aerosol generating film comprising a cellulosic film-forming agent, nicotine, and an aerosol-forming agent. The aerosol generating film may further contain a cellulosic reinforcing agent. The aerosol generating film may further contain water, preferably less than 30% by weight.

[0132] As used herein, the term “film” is used to describe a solid layered element having a thickness less than its width or length. A film may be self-supporting. In other words, a film may have cohesive and mechanical properties that allow it to be separated from a support surface, even if it is obtained by casting a film-forming formulation onto a support surface. Alternatively, a film may be placed on a support or sandwiched between other materials. This can enhance the mechanical stability of the film.

[0133] The aerosol-forming material content of the aerosol-generating film is within the range defined above for aerosol-generating substrates having a relatively high aerosol-forming material content.

[0134] In the context of the present invention, the term "cellulose-based film-forming agent" is used to refer to a cellulose polymer having the ability to form a continuous film, either by itself or in the presence of an auxiliary thickener. Preferably, the cellulose-based film-forming agent is selected from the group consisting of hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), ethylcellulose (EC), hydroxyethyl methylcellulose (HEMC), hydroxyethylcellulose (HEC), hydroxypropylcellulose (HPC), and combinations thereof. In a particularly preferred embodiment, the cellulose-based film-forming agent is HPMC.

[0135] The aerosol-generating film may contain a cellulose-based film-forming agent of 10% to 40% by weight, or 15% to 35% by weight, or 20% to 30% by weight, on a dry weight basis.

[0136] The aerosol-generating film preferably further contains a cellulose-based reinforcing agent. The cellulose-based reinforcing agent is preferably selected from the group consisting of cellulose fibers, microcrystalline cellulose (MCC), cellulose powder, and combinations thereof.

[0137] The aerosol-generating film may contain a cellulosic reinforcing agent of 0.5% to 40% by dry weight, or 5% to 30% by dry weight, or 10% to 25% by dry weight.

[0138] The aerosol generating film may further contain carboxymethylcellulose, preferably sodium carboxymethylcellulose. The aerosol generating film may have a carboxymethylcellulose content of 1% to 15% by weight, or 2% to 12% by weight, or 4% to 10% by weight, on a dry weight basis.

[0139] The aerosol generating film preferably contains nicotine. The term "nicotine" as used herein in connection with the present invention is used to refer to nicotine, nicotine base, or nicotine salt. In embodiments in which the aerosol generating film contains a nicotine base or nicotine salt, the amounts of nicotine listed herein are, respectively, amounts of free base nicotine or amounts of protonated nicotine.

[0140] The aerosol-generating film may contain natural or synthetic nicotine.

[0141] The aerosol generating film may contain one or more monobasic nicotine salts. As used herein in connection with the present invention, the term "monobasic nicotine salt" is used to refer to a nicotine salt of a monobasic acid.

[0142] Preferably, the aerosol generating film contains 0.5% to 10% by weight of nicotine, or 1% to about 8% by weight of nicotine, or about 2% to about 6% by weight of nicotine, on a dry weight basis.

[0143] The aerosol generating film may be a substantially tobacco-free aerosol generating film.

[0144] In preferred embodiments, the aerosol generating film contains an acid. More preferably, the aerosol generating film contains one or more organic acids. Even more preferably, the aerosol generating film contains one or more carboxylic acids. In particularly preferred embodiments, the acid is lactic acid, benzoic acid, fumaric acid, or levulinic acid.

[0145] The aerosol-generating film preferably contains 0.25% to 3.5% by weight of acid, or 0.5% to 3% by weight of acid, or about 1% to 2.5% by weight of acid, on a dry weight basis.

[0146] In preferred embodiments, the aerosol-generating film has a thickness of about 0.1 mm to about 1 mm, more preferably about 0.1 mm to about 0.75 mm, and even more preferably about 0.1 mm to about 0.5 mm. In particularly preferred embodiments, a layer of film-forming composition is formed having a thickness of about 50 micrometers to 400 micrometers, more preferably about 100 micrometers to 200 micrometers.

[0147] The aerosol-generating film may optionally be provided within an aerosol-generating substrate on a suitable carrier element.

[0148] In alternative embodiments of the present invention, the aerosol-generating substrate may include a gel composition comprising nicotine, at least one gelling agent, and an aerosol-forming body. The gel composition is preferably substantially free of tobacco.

[0149] The preferred weight range of nicotine in the gel composition is the same as that defined above in relation to the aerosol generating film.

[0150] The gel composition preferably contains at least 50 weight percent, more preferably at least 60 weight percent, and more preferably at least 70 weight percent, of aerosol-forming material on a dry weight basis. The gel composition may contain up to 80 weight percent of aerosol-forming material. The aerosol-forming material in the gel composition is preferably glycerol.

[0151] The gel composition preferably contains at least one gelling agent. Preferably, the gel composition contains a total amount of gelling agent ranging from about 0.4% to about 10% by weight, or about 0.5% to about 8% by weight, or about 1% to about 6% by weight, or about 2% to about 4% by weight, or about 2% to about 3% by weight.

[0152] The term "gelling agent" refers to a compound that, when added homogeneously to a mixture of 50% water and 50% glycerol in an amount of approximately 0.3% by weight, forms a solid medium or supporting matrix, leading to the formation of a gel. Examples of gelling agents, though not limited to them, include hydrogen-linked gelling agents and ionic-linked gelling agents.

[0153] The term "hydrogen-bonding crosslinking gelling agent" refers to a gelling agent that forms non-covalent or physical crosslinks via hydrogen bonds. A hydrogen-bonding crosslinking gelling agent may include one or more of galactomannan, gelatin, agarose, konjac gum, or agar. It is preferable that the hydrogen-bonding crosslinking gelling agent includes agar.

[0154] The term "ionic crosslinking gelling agent" refers to a gelling agent that forms non-covalent or physical crosslinks via ionic bonding. Ionic crosslinking gelling agents may include low acylgelanes, pectin, kappa-carrageenan, iota-carrageenan, or alginates. Ionic crosslinking gelling agents may preferably include low acylgelanes.

[0155] The gelling agent may contain one or more biopolymers. The biopolymers may be formed from polysaccharides.

[0156] Examples of biopolymers include gellan gum (natural gellan gum, low-acyl gellan gum, high-acyl gellan gum, and low-acyl gellan gum are preferred), xanthan gum, alginate (alginic acid), agar, and guar gum. It is preferable that the composition contains xanthan gum. The composition may contain two biopolymers. The composition may contain three biopolymers. The composition may contain two biopolymers in substantially equal weights. The composition may contain three biopolymers in substantially equal weights.

[0157] The gel composition may further contain a thickening agent. Surprisingly, thickening agents combined with hydrogen-bonding crosslinking gelling agents appear to support solid media and maintain the gel composition even when it contains high levels of glycerol.

[0158] The term "thickener" refers to a compound that, when uniformly added in an amount of 0.3 weight percent to a mixture of 50 weight percent water and 50 weight percent glycerol at 25°C, increases viscosity without causing gel formation, causing the mixture to remain in a fluid state or to stay fluid.

[0159] The gel composition preferably contains a thickening agent in an amount ranging from about 0.2% to about 5% by weight, or about 0.5% to about 3% by weight, or about 0.5% to about 2% by weight, or about 1% to about 2% by weight.

[0160] The thickener may contain one or more of the following: xanthan gum, carboxymethylcellulose, microcrystalline cellulose, methylcellulose, gum arabic, guar gum, lambda carrageenan, or starch. It is preferable that the thickener contains xanthan gum.

[0161] The gel composition may further contain divalent cations. Preferably, the divalent cations include calcium ions such as calcium lactate in the solution. Divalent cations (such as calcium ions) can assist in gel formation in compositions containing gelling agents, such as ion-crosslinking gelling agents. Ionic effects may assist in gel formation. Divalent cations may be present in the gel composition in the range of about 0.1 to about 1 weight percent, or about 0.5 weight percent.

[0162] The gel composition may further contain an acid. The acid may include a carboxylic acid such as levulinic acid or lactic acid.

[0163] The gel composition preferably contains some water. The gel composition is more stable when it contains some water. Preferably, the gel composition contains about 8% to about 32% by weight water, or about 15% to about 25% by weight water, or about 18% to about 22% by weight water, or about 20% by weight water.

[0164] Preferably, when a gel composition is used, the aerosol generating substrate comprises a porous medium filled with the gel composition. The term “porous” is used herein to mean a material that provides a plurality of pores or openings that allow air to pass through the material.

[0165] In certain embodiments of the present invention, the aerosol generating article further includes one or more elongated susceptor elements within a rod of the aerosol generating substrate. For example, one or more elongated susceptor elements may be arranged substantially along their longitudinal axis within the aerosol generating rod and may be in thermal contact with the aerosol generating substrate.

[0166] As used herein in relation to the present invention, the term "susceptor element" refers to a material capable of converting electromagnetic energy into heat. Eddy currents induced within a susceptor element, when located within a fluctuating electromagnetic field, cause heating of the susceptor element. Since the susceptor element is located in thermal contact with the aerosol-generating substrate, the aerosol-generating substrate is heated by the susceptor element.

[0167] When used to describe a susceptor element, the term “elongated” means that the susceptor element has a length dimension that is greater than its width dimension or thickness dimension, for example, more than twice its width dimension or thickness dimension.

[0168] The susceptor element is positioned substantially along the long axis within the rod of the aerosol generating substrate. This means that the length dimension of the elongated susceptor element is positioned substantially parallel to the long axis of the rod, for example, within ±10 degrees of the long axis of the rod. In a preferred embodiment, the elongated susceptor element may be positioned at the radial center within the rod and extend along the long axis of the rod.

[0169] The susceptor element is preferably in the form of a pin, rod, strip, or blade.

[0170] The susceptor element preferably has a width of 1 mm to 5 mm.

[0171] The susceptor element can generally have a thickness of 0.01 mm to 2 mm, for example, 0.5 mm to 2 mm. In some embodiments, the susceptor element preferably has a thickness of 10 micrometers to 500 micrometers, more preferably 10 micrometers to 100 micrometers.

[0172] Preferably, the elongated susceptor element has a length equal to or shorter than the length of the aerosol-generating segment into which it is incorporated. Preferably, the elongated susceptor element has a length equal to the length of the aerosol-generating rod into which it is incorporated.

[0173] The susceptor element may be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from the aerosol-generating substrate. Preferred susceptor elements include metals or carbon.

[0174] A preferred susceptor element may include, or consist of, a ferromagnetic material such as a ferromagnetic alloy, ferrite iron, ferromagnetic steel, or stainless steel. A preferred susceptor element may also be aluminum, or contain aluminum.

[0175] Preferably, the rod of the aerosol generating substrate is surrounded by a wrapper. The wrapper may be a paper wrapper or a non-paper wrapper.

[0176] Suitable paper wrappers for use in specific embodiments of the present invention are known in the art and include, but are not limited to, cigarette papers and filter plug wrappers. Suitable non-paper wrappers for use in specific embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco material.

[0177] The aerosol-generating article according to this disclosure may further include an upstream section located upstream of the rod of the aerosol-generating substrate. The upstream section is preferably located immediately upstream of the rod of the aerosol-generating substrate. The upstream section is preferably extending between the upstream end of the aerosol-generating article and the rod of the aerosol-generating substrate. The upstream section may include one or more upstream elements located upstream of the rod of the aerosol-generating substrate.

[0178] The upstream element advantageously prevents direct physical contact between the aerosol-generating substrate and the upstream end of the rod. Furthermore, the presence of the upstream element helps prevent any loss of the substrate, which can be advantageous, for example, when the substrate contains particulate plant material.

[0179] If the rod of the aerosol generating substrate contains shredded tobacco such as tobacco cut filler, the upstream section or its elements may additionally help prevent the loss of loose tobacco particles from the upstream end of the article. This can be particularly important, for example, when the density of the shredded tobacco is relatively low.

[0180] The upstream element may be a porous plug element. Preferably, the upstream element has a porosity of at least 50 percent in the longitudinal direction of the aerosol-generating article. More preferably, the upstream element has a porosity of 50 percent to 90 percent in the longitudinal direction. The porosity of the upstream element in the longitudinal direction is defined by the ratio of the cross-sectional area of ​​the material forming the upstream element to the internal cross-sectional area of ​​the aerosol-generating article at the location of the upstream element.

[0181] The upstream element may be made of a porous material or may include multiple openings. This can be achieved, for example, by laser drilling. Preferably, the multiple openings are uniformly distributed across the cross-section of the upstream element.

[0182] The porosity or permeability of the upstream element may be advantageously designed to provide an aerosol-generating article having a specific overall drawdown resistance (RTD) that does not substantially affect the filtration provided by the other parts of the article.

[0183] The upstream element may be formed from a material that is impermeable to air. In such embodiments, the aerosol generating article may be configured so that air flows into the rods of the aerosol generating substrate through appropriate ventilation means provided within the wrapper.

[0184] The upstream element may be made of any material suitable for use in an aerosol generating article. The upstream element may be made of the same material used for one of the other components of the aerosol generating article, such as a mouthpiece, cooling element, or support element. Suitable materials for the upstream element include filter materials, ceramics, polymer materials, cellulose acetate, cardboard, zeolite, or aerosol generating substrates. The upstream element is preferably formed from a cellulose acetate plug.

[0185] The upstream element is preferably made of a heat-resistant material. For example, the upstream element is preferably made of a material that can withstand temperatures up to 350 degrees Celsius. This ensures that the upstream element is not adversely affected by the heating means used to heat the aerosol generating substrate.

[0186] In certain preferred embodiments, the upstream element is formed by a solid cylindrical plug element having a filled cross-section. Such a plug element may be referred to as a “plain” element. The solid plug element may be porous but not have a tubular shape and therefore does not provide a flow channel along its longitudinal axis. The solid plug element preferably has a substantially uniform cross-section.

[0187] In such embodiments, the upstream element preferably has a drawout resistance (RTD) of less than 25 mmH2O, less than 22 mmH2O, or less than 20 mmH2O. Preferably, the upstream element has an RTD of at least 10 mmH2O, or at least 12 mmH2O, or at least 14 mmH2O, or at least 16 mmH2O. For example, the upstream element may have an RTD of 10 mmH2O to 25 mmH2O, or 12 mmH2O to 22 mmH2O, or 14 mmH2O to 20 mmH2O, or 16 mmH2O to 20 mmH2O.

[0188] In other embodiments, the upstream element is formed from a hollow tubular segment defining a longitudinal cavity that provides an unrestricted flow channel. In such embodiments, the upstream element can provide protection to the aerosol-generating substrate as described above, while having only minimal effect on the overall draw-to-discard (RTD) and filtration properties of the article.

[0189] Preferably, the diameter of the axial cavity of the hollow tubular segment forming the upstream element is at least about 4 mm, more preferably at least about 4.5 mm, more preferably at least about 5 mm, and more preferably at least about 5.5 mm. Preferably, the diameter of the axial cavity is maximized to minimize the RTD of the upstream section or its upstream element. The inner diameter of the upstream element may be about 5.1 mm.

[0190] Preferably, the wall thickness of the hollow tubular segment is less than about 2 millimeters, more preferably less than about 1.5 millimeters, and more preferably less than about 1.25 millimeters. The wall thickness of the hollow tubular segment defining the upstream element may be about 1 mm.

[0191] In such embodiments, the upstream element preferably has an RTD of less than 10 mmH2O, more preferably less than 5 mmH2O, and more preferably less than 2.5 mmH2O. Preferably, in such embodiments, the upstream element has an RTD of at least 0.1 mmH2O, or at least about 0.25 mmH2O, or at least about 0.5 mmH2O. For example, the upstream element may have an RTD of 0.1 mmH2O to 10 mmH2O, or 0.25 mmH2O to 5 mmH2O, or 0.5 mmH2O to 2.5 mmH2O.

[0192] The upstream element preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article. Preferably, the outer diameter of any upstream element before compression is about 6 mm to about 8 mm, and more preferably about 7 mm to about 7.5 mm. Preferably, the upstream element has an outer diameter of about 7.1 mm.

[0193] Preferably, the upstream element has a length of 2 to 8 millimeters, more preferably 3 to 7 millimeters, and more preferably 4 to 6 millimeters. In a particularly preferred embodiment, the upstream element has a length of about 5 millimeters.

[0194] The upstream element is preferably surrounded by a wrapper such as a plug wrap. The upstream element is preferably connected to the rod of the aerosol generating substrate and, optionally, to at least a portion of the downstream section by an outer wrapper as described herein.

[0195] The aerosol generating article according to the present invention may further comprise a downstream filter segment. The downstream filter segment may be located at the downstream end of the aerosol generating article. The downstream end of the downstream filter segment may define the downstream end of the aerosol generating article.

[0196] The downstream filter segment may be located downstream of the aerosol cooling element, as described above. The downstream filter segment may extend between the aerosol cooling element and the downstream end of the aerosol generating article.

[0197] The downstream filter segment is preferably a solid plug, which may also be described as a "plain" plug and is non-tubular. Therefore, the filter segment preferably has a substantially uniform cross-sectional area.

[0198] The downstream filter segment is preferably formed of a fibrous filter material. The fibrous filter material may be for filtering aerosols generated from the aerosol generating substrate. Suitable fibrous filter materials will be known to those skilled in the art. Particularly preferably, at least one downstream filter segment includes a cellulose acetate filter segment formed of cellulose acetate tow.

[0199] In certain preferred embodiments, the downstream section includes a single downstream filter segment. In alternative embodiments, the downstream section includes two or more downstream filter segments aligned axially, with their ends touching each other.

[0200] The downstream filter segment preferably has a low particle filtration efficiency.

[0201] The downstream filter segment is preferably surrounded by a plug wrap. The downstream filter segment is preferably not permeable to air so that air does not enter the aerosol-generating article along the downstream filter segment.

[0202] The downstream filter segment is preferably connected by a chipping wrapper to one or more adjacent upstream components of the aerosol-generating article.

[0203] The downstream filter segment preferably has an outer diameter approximately equal to the outer diameter of the aerosol generating article. The outer diameter of the downstream filter segment may be substantially the same as the outer diameter of the hollow tubular cooling element.

[0204] Preferably, the outer diameter of the downstream filter segment is 5 mm to 12 mm, more preferably 6 mm to 10 mm, and more preferably 7 mm to 8 mm. In some embodiments, the outer diameter of the downstream filter segment may be less than 7 mm, for example, 5 mm to 7 mm or 6 mm to 7 mm.

[0205] As described above, the downstream filter segment may be formed from a fibrous filtration material. The downstream filter segment may be formed from a porous material. The downstream filter segment may be formed from a biodegradable material. The downstream filter segment may be formed from a cellulose material such as cellulose acetate.

[0206] The downstream filter segment may be formed from a polylactic acid-based material. The downstream filter segment may be formed from a bioplastic material, preferably a starch-based bioplastic material. The downstream filter segment may be manufactured by injection molding or extrusion molding.

[0207] The length of the downstream filter segment may be 5 mm to 25 mm, or 10 mm to 25 mm, or 5 mm to 20 mm, or 10 mm to 20 mm, or 10 mm to 15 mm.

[0208] The ratio of the length of the downstream filter segment to the length of the aerosol cooling element is preferably at least 1, more preferably at least 1.1, more preferably at least 1.2, more preferably at least 1.3, and more preferably at least 1.4. The ratio of the length of the downstream filter segment to the length of the aerosol cooling element may be up to 2, preferably up to 1.8.

[0209] The downstream filter segment preferably has a draw-out resistance (RTD) of less than 15 mmH2O, less than 12 mmH2O, or less than 10 mmH2O. Preferably, the downstream filter segment has an RTD of at least 2 mmH2O, or at least 4 mmH2O, or at least 6 mmH2O. For example, the downstream filter segment may have an RTD of 2 mmH2O to 15 mmH2O, or 4 mmH2O to 12 mmH2O, or 6 mmH2O to 10 mmH2O. In a particularly preferred embodiment, the downstream filter segment has an RTD of about 8.5 mmH2O.

[0210] The aerosol-generating article preferably has an overall length of 40 mm to 80 mm, or 40 mm to about 70 mm, or 40 mm to about 60 mm, or 45 mm to about 80 mm, or about 45 mm to about 70 mm, or 45 mm to about 60 mm, or 50 mm to 80 mm, or 50 mm to about 70 mm, or about 50 mm to about 60 mm. In an exemplary embodiment, the overall length of the aerosol-generating article is about 45 mm.

[0211] The aerosol-generating article preferably has an outer diameter of about 5 mm to about 12 mm, or about 6 mm to about 12 mm, or about 7 mm to about 12 mm, or about 5 mm to about 10 mm, or about 6 mm to about 10 mm, or about 7 mm to about 10 mm, or about 5 mm to about 8 mm, or about 6 mm to about 8 mm, or about 7 mm to about 8 mm. In other embodiments, the aerosol-generating article has an outer diameter of less than 7 mm.

[0212] The overall RTD of the aerosol-generating article is preferably at least 10 mmH2O, more preferably at least 15 mmH2O, more preferably at least 20 mmH2O, more preferably at least 25 mmH2O, and more preferably at least 30 mmH2O.

[0213] The overall RTD of the aerosol-generating article is preferably 70 mmH2O or less, more preferably 60 mmH2O or less, more preferably 55 mmH2O or less, more preferably 50 mmH2O or less, and more preferably 45 mmH2O or less.

[0214] For example, the overall RTD of an aerosol-generating article could be 10 mmH2O to 70 mmH2O, or 15 mmH2O to 60 mmH2O, or 20 mmH2O to 55 mmH2O, or 25 mmH2O to 45 mmH2O, or 30 mmH2O to 45 mmH2O.

[0215] According to the present invention, an aerosol generating system is further provided, comprising an aerosol generating article according to the invention described in detail above, and an aerosol generating device comprising a device cavity for receiving the aerosol generating article and at least one heating element provided around or near the device cavity.

[0216] The aerosol generator comprises a body or housing that defines a device cavity. The device cavity may extend between a distal end and an orifice (or proximal) end. The distal end of the device cavity may be a closed end, and the proximal end may be an open end. The aerosol generating article may be inserted into the device cavity through the open end of the device cavity. The device cavity may be cylindrical in shape to accommodate the same shape as the aerosol generating article.

[0217] The aerosol generator further comprises a heater containing one or more heating elements. The heater may be any suitable type of heater.

[0218] In some embodiments, the heater is positioned to heat the outer surface of the aerosol generating substrate. In some embodiments, the heater is positioned for insertion into the aerosol generating substrate when the aerosol generating substrate is received within the cavity. The heater may be located within the device cavity.

[0219] The heater may comprise a single heater element or multiple heater elements. Any suitable type of heater element may also be used. The heater may comprise at least one of a resistance heater and an induction heating assembly. The heater may comprise an external heater or an external heating element.

[0220] A heater can externally heat the rod of the aerosol generating substrate when the aerosol generating article is received inside the aerosol generating device. Such an external heater may be provided on at least one side of the rod of the aerosol generating substrate when it is received inside the heating chamber of the aerosol generating device.

[0221] The heater may include at least one resistive heating element. The at least one resistive heating element can be any suitable type of resistive heating element. In some embodiments, the heater comprises only one resistive heating element. In some embodiments, the heater comprises multiple resistive heating elements. The heater may include at least one resistive heating element. It is preferable that the heater assembly comprises multiple resistive heating elements. It is preferable that the resistive heating elements are electrically connected in a parallel arrangement.

[0222] In some embodiments, at least one heating element includes an electrically insulated substrate, and at least one resistance heating element is provided on an electrically insulated substrate.

[0223] In some embodiments, the heater comprises an induction heating assembly, which may include an inductor coil. The aerosol generator may include a power supply configured to supply a high-frequency oscillating current to the inductor coil.

[0224] The heater may include an induction heating element. The induction heating element may be a susceptor element. In these embodiments, the susceptor element is preferably located in contact with the aerosol generating substrate. In some embodiments, the susceptor element is located within the aerosol generating device. In these embodiments, the susceptor element may be located within the heating chamber. The aerosol generating device may include only one susceptor element. The aerosol generating device may comprise multiple susceptor elements. In some embodiments, the susceptor element is preferably arranged to heat the outer surface of the aerosol generating substrate.

[0225] The susceptor element may contain any suitable material. Suitable materials for elongated susceptor elements include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel, nickel-containing compounds, titanium, and composites of metallic materials. Some susceptor elements contain metal or carbon. Advantageously, the susceptor element may contain or consist of ferromagnetic materials such as ferrite iron, ferromagnetic alloys such as ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrite. A suitable susceptor element may be aluminum, or may contain aluminum.

[0226] As described in more detail above, in some embodiments in which the aerosol generator includes an induction coil, the aerosol generating article may include at least one susceptor element.

[0227] The aerosol generator may include an airflow channel extending between a channel inlet and a channel outlet. The airflow channel may be configured to establish fluid communication between the inside of the device cavity and the outside of the aerosol generator. The airflow channel of the aerosol generator may be defined within the body of the aerosol generator, enabling fluid communication between the inside of the heating chamber and the outside of the aerosol generator. When an aerosol-generating article is received in the heating chamber, the airflow channel may be configured to provide airflow to the article in order to deliver the generated aerosol to a user who draws it in from the mouth end of the article.

[0228] The aerosol generator may be equipped with a power supply. The power supply may be a DC power supply. In some embodiments, the power supply is a battery. [Examples]

[0229] A non-exclusive list of non-limiting embodiments is provided below. One or more features of these embodiments may be combined with any one or more features of other embodiments, models, or aspects described herein.

[0230] Example 1. An aerosol generating article for generating an inhalable aerosol upon heating, comprising: a rod of an aerosol generating substrate; a support element located downstream of the rod of the aerosol generating substrate, comprising a first hollow tubular element having an inner diameter D1 and defining a cavity in the longitudinal direction that provides an unrestricted flow channel; and an aerosol cooling element located downstream of the support element, comprising a second hollow tubular element having an inner diameter D2 of at least 6 mm and defining a cavity in the longitudinal direction that provides an unrestricted flow channel. Example 2. The aerosol generating article according to Example 1, wherein the ratio of the inner diameter D2 of the second hollow tubular element to the inner diameter D1 of the first hollow tubular element is at least 1.8. Example 3. The aerosol generating article according to Example 1 or 2, wherein the second hollow tubular element of the aerosol cooling element has an inner diameter D2 of at least 6.5 mm. Example 4. An aerosol-generating article according to any one of Examples 1 to 3, wherein the inner diameter D2 of the second hollow tubular element is less than 7.3 millimeters. Example 5. An aerosol-generating article according to any one of Examples 1 to 4, wherein the wall thickness of the second hollow tubular element is less than 0.5 millimeters. Example 6. An aerosol-generating article according to any of Examples 1 to 5, wherein the wall thickness of the second hollow tubular element is less than 0.35 millimeters. Example 7. An aerosol-generating article according to any one of Examples 1 to 6, wherein the wall thickness of the second hollow tubular element is at least 0.1 millimeters. Example 7. An aerosol generating article according to any of the preceding embodiments, wherein the second hollow tubular element is a paper tube formed from one or more layers of paper. Example 8. The aerosol generating article according to Example 7, wherein the second hollow tubular element is a paper tube formed from multiple overlapping layers of paper. Example 9. The aerosol generating article according to Example 8, wherein multiple overlapping paper layers are spirally wound around the longitudinal axis of a second hollow tubular element. Example 10. An aerosol-generating article according to any one of Examples 7 to 9, wherein each paper layer of the paper tube has a thickness of 30 microns to 200 microns. Example 11. The aerosol generating article according to Example 10, wherein the paper layers forming the paper tube have different thicknesses from each other. Example 12. The aerosol generating article according to Example 11, wherein the paper tube comprises one or more layers of a first paper material and one or more layers of a second paper material, and the thickness of the second paper material is at least 25 microns greater than the thickness of the first paper material. Example 13. An aerosol generating article according to any one of Examples 7 to 12, wherein each paper layer of the paper tube has a basis weight of 25 grams / m² to 150 grams / m². Example 14. The aerosol generating article according to Example 13, wherein the paper layers forming the paper tube have different basis weights. Example 15. The aerosol generating article according to Example 13 or 14, wherein the paper tube comprises one or more layers of a first paper material and one or more layers of a second paper material, and the basis weight of the second paper material is at least 25 grams / square meter greater than the basis weight of the first paper material. Example 16. An aerosol-generating article according to any one of Examples 7 to 15, wherein the paper tube contains at least one hydrophobic paper layer. Example 17. The aerosol-generating article according to Example 16, wherein a hydrophobic paper layer provides the inner surface of the paper tube. Example 18. The aerosol-generating article according to Example 16 or 17, wherein the hydrophobic paper layer comprises a hydrophobic coating layer applied to its surface. Example 19. An aerosol-generating article according to any one of Examples 16 to 18, wherein the hydrophobic paper layer contains polyvinyl alcohol, silicone, or wax. Example 20. An aerosol generating article according to any of Examples 1 to 19, wherein the aerosol cooling element has a length of 5 mm to 15 mm. Example 21. An aerosol generating article according to any of Examples 1 to 20, wherein the aerosol cooling element has a length of less than 10 millimeters. Example 22. An aerosol generating article according to any one of Examples 1 to 21, wherein the ratio of the length of the aerosol cooling element to the total length of the aerosol generating article substrate is at least 0.13. Example 23. An aerosol generating article according to any one of Examples 1 to 22, wherein the aerosol cooling element further includes a ventilation zone positioned along a second hollow tubular element. Example 24. The aerosol-generating article according to Example 23, wherein the aerosol-generating article has an air permeability level of 30 percent to 40 percent. Example 25. An aerosol generating article according to any of Examples 1 to 24, wherein the first hollow tubular element has an inner diameter D1 of less than 5.5 mm. Example 26. An aerosol generating article according to any of Examples 1 to 25, wherein the first hollow tubular element has an inner diameter D1 of less than 3.5 mm. Example 27. An aerosol generating article according to any of Examples 1 to 26, wherein the first hollow tubular element has an inner diameter D1 of at least 1.5 mm. Example 28. The aerosol generating article according to Examples 1 to 27, wherein the ratio of the inner diameter of the second hollow tubular element to the inner diameter of the first hollow tubular element is at least 2.1. Example 29. An aerosol generating article according to any of Examples 1 to 28, wherein the ratio of the inner diameter of the second hollow tubular element to the inner diameter of the first hollow tubular element is less than 2.75. Example 30. An aerosol-generating article according to any of Examples 1 to 29, wherein the wall thickness of the first hollow tubular element is at least 1 millimeter. Example 31. An aerosol-generating article according to any of Examples 1 to 30, wherein the wall thickness of the first hollow tubular element is less than 3.5 millimeters. Example 32. An aerosol generating article according to any one of Examples 1 to 31, wherein the first hollow tubular element is a hollow acetate tube formed from cellulose acetate. Example 33. An aerosol generating article according to any of Examples 1 to 32, wherein the support element has a length of 5 mm to 15 mm. Example 34. An aerosol generating article according to any of Examples 1 to 33, wherein the support element has a length of less than 10 millimeters. Example 35. An aerosol generating article according to any one of Examples 1 to 34, wherein the ratio of the length of the support element to the total length of the aerosol generating article is at least 0.13. Example 36. An aerosol generating article according to any one of Examples 1 to 35, wherein the ratio of the length of the aerosol cooling element to the length of the support element is at least 0.8. Example 37. An aerosol generating article according to any one of Examples 1 to 36, wherein the ratio of the length of the aerosol cooling element to the length of the support element is at least 1.5. Example 38. An aerosol generating article according to any one of Examples 1 to 37, wherein the rod of the aerosol generating substrate has a length of at least 8 millimeters. Example 39. An aerosol generating article according to any one of Examples 1 to 38, wherein the rod of the aerosol generating substrate contains homogenized tobacco material. Example 40. An aerosol generating article according to any one of Examples 1 to 39, wherein the rod of the aerosol generating substrate contains a tobacco cut filler. Example 41. An aerosol generating article according to any one of Examples 1 to 40, wherein the rod of the aerosol generating substrate contains a cellulose-based film-forming agent, nicotine, and an aerosol-forming body. Example 42. An aerosol generating article according to any one of Examples 1 to 41, wherein the rod of the aerosol generating substrate comprises one or more elongated susceptor elements. Example 43. An aerosol generating article according to any one of Examples 1 to 42, further comprising an upstream element located upstream of the rod of the aerosol generating substrate. Example 44. An aerosol generating article according to any one of Examples 1 to 43, further comprising a downstream filter segment downstream of the aerosol cooling element. Example 45. An aerosol generating system comprising an aerosol generating article described in any of Examples 1 to 44, and an aerosol generating device comprising a device cavity for receiving the aerosol generating article and at least one heating element provided around or near the device cavity.

[0231] In the following, the present invention will be further described with reference to the attached drawing Figure 1, which shows a schematic side cross-sectional view of an aerosol generating article according to the present invention.

[0232] The aerosol generating article 10 shown in Figure 1 comprises a rod 12 of an aerosol generating substrate 12 and a downstream section 14 located downstream of the rod 12 of the aerosol generating substrate. Furthermore, the aerosol generating article 10 includes an upstream section 16 located upstream of the rod 12 of the aerosol generating substrate. Thus, the aerosol generating article 10 may extend from the upstream or distal end 18 to the downstream or oral end 20.

[0233] The aerosol-generating article has a total length of approximately 45 millimeters.

[0234] The downstream section 14 includes a support element 22 located immediately downstream of the rod 12 of the aerosol generating substrate, and the support element 22 is aligned with the rod 12 in the longitudinal direction. In the embodiment of Figure 1, the upstream end of the support element 22 abuts against the downstream end of the rod 12 of the aerosol generating substrate. In addition, the downstream section 14 includes an aerosol cooling element 24 located immediately downstream of the support element 22, and the aerosol cooling element 24 is aligned with the rod 12 and the support element 22 in the longitudinal direction. In the embodiment of Figure 1, the upstream end of the aerosol cooling element 24 abuts against the downstream end of the support element 22.

[0235] The support element 22 includes a first hollow tubular element 26. The first hollow tubular element 26 is provided in the form of a hollow cylindrical tube made of cellulose acetate. The first hollow tubular element 26 defines an internal cavity 28 that extends all the way from the upstream end 30 of the first hollow tubular element 26 to the downstream end 32 of the first hollow tubular element 26. The internal cavity 28 is substantially empty, and therefore substantially unrestricted airflow is possible along the internal cavity 28. The first hollow tubular element 26, and consequently the support element 22, does not substantially contribute to the overall RTD of the aerosol generating article 10. Specifically, the RTD of the first hollow tubular element 26 is substantially 0 mmH2O.

[0236] The first hollow tubular element 26 has a length of approximately 8 millimeters, an outer diameter of approximately 7.25 millimeters, and an inner diameter (D1) of approximately 3.3 millimeters. Therefore, the thickness of the peripheral wall of the first hollow tubular element 26 is approximately 2 millimeters.

[0237] The aerosol cooling element 24 comprises a second hollow tubular element 34. The second hollow tubular element 34 is provided in the form of a paper tube formed from three spirally wound paper layers. The first inner paper layer has a thickness of 137 microns and a basis weight of 120 gsm. The second intermediate paper layer has a thickness of 100 microns and a basis weight of 78 gsm. The third outer paper layer has a thickness of 45 microns and a basis weight of 32 gsm.

[0238] The second hollow tubular element 34 defines an internal cavity 36 that extends from the upstream end 38 of the second hollow tubular element 34 all the way to the downstream end 40 of the second hollow tubular element 34. The internal cavity 36 is substantially empty, and therefore substantially unrestricted airflow is possible along the internal cavity 36. The second hollow tubular element 34, and consequently the aerosol cooling element 24, contribute substantially nothing to the overall RTD of the aerosol generating article 10. Specifically, the RTD of the second hollow tubular element 34 is substantially 0 mmH2O.

[0239] The second hollow tubular element 34 has a length of approximately 8 millimeters, an outer diameter of approximately 7.25 millimeters, and an inner diameter (D2) of approximately 6.9 millimeters. Therefore, the thickness of the peripheral wall of the second hollow tubular element 34 is approximately 0.18 millimeters. The ratio of the inner diameter (D2) of the second hollow tubular element 34 to the inner diameter (D1) of the first hollow tubular element 26 is approximately 2.1.

[0240] The aerosol-generating article 10 includes a ventilation zone 60 provided along a second hollow tubular element 34. More specifically, the ventilation zone 60 is provided approximately 2 millimeters from the upstream end 38 of the second hollow tubular element 34. The ventilation level of the aerosol-generating article 10 is approximately 35 percent.

[0241] In the embodiment shown in Figure 1, the downstream section 14 further comprises a mouthpiece element 42 located immediately downstream of the aerosol cooling element 24. As shown in Figure 1, the upstream end of the mouthpiece element 42 abuts against the downstream end 40 of the second hollow tubular element 34.

[0242] The mouthpiece element 42 is provided in the form of a cylindrical plug made of low-density cellulose acetate.

[0243] The mouthpiece element 42 has a length of approximately 12 mm and an outer diameter of approximately 7.25 mm. The RTD of the mouthpiece element 42 is approximately 12 mm of H2O.

[0244] Rod 12 contains one of the aerosol-generating substrates of the type described above.

[0245] The rod 12 of the aerosol generating substrate has an outer diameter of approximately 7.25 millimeters and a length of approximately 12 millimeters.

[0246] The aerosol generating article 10 further comprises an elongated susceptor element 44 within the rod 12 of the aerosol generating substrate. More specifically, the susceptor element 44 is positioned substantially along its long axis within the aerosol generating substrate, substantially parallel to the longitudinal direction of the rod 12. As shown in the drawing of Figure 1, the susceptor element 44 is positioned radially centrally within the rod and extends effectively along the long axis of the rod 12.

[0247] The susceptor element 44 extends along the entire length of the rod 12, from its upstream end to its downstream end. In practice, the susceptor element 44 has substantially the same length as the rod 12 of the aerosol generating substrate.

[0248] In the embodiment shown in Figure 1, the susceptor element 44 is provided in the form of a strip, having a length of about 12 millimeters, a thickness of about 60 micrometers, and a width of about 4 millimeters. The upstream section 16 comprises an upstream element 46 located immediately upstream of the rod 12 of the aerosol generating substrate, the upstream element 46 being aligned with the rod 12 in the longitudinal direction. In the embodiment shown in Figure 1, the downstream end of the upstream element 46 abuts against the upstream end of the rod 12 of the aerosol generating substrate. This advantageously prevents the susceptor element 44 from detaching. Furthermore, this ensures that consumers cannot accidentally come into contact with the heated susceptor element 44 after use.

[0249] The upstream element 46 is supplied in the form of a cylindrical plug of cellulose acetate surrounded by a rigid wrapper. The upstream element 46 has a length of approximately 5 millimeters. The RTD of the upstream element 46 is approximately 30 millimeters of H2O.

[0250] For the purposes of this specification and the appended claims, unless otherwise indicated, all numerical values ​​representing quantities, amounts, percentages, etc., should be understood in all instances as being modified by the term “approximately.” Furthermore, all ranges include the disclosed maximum and minimum points and any intermediate ranges therewith, which may or may not be specifically listed herein. Thus, in this context, the number A is understood as A ± 10%. In this context, the number A may be considered to include numerical values ​​that fall within the general standard error to the measured value of the characteristic that the number A modifies. In some instances used in the appended claims, the number A may deviate by the percentages listed above, provided that the amount of deviation of A does not substantially affect the fundamental and novel characteristics of the claimed invention. Furthermore, all ranges include the disclosed maximum and minimum points and any intermediate ranges therewith, which may or may not be specifically listed herein.

Claims

1. An aerosol generating article for generating an inhalable aerosol upon heating, wherein the aerosol generating article is A rod of the aerosol generating substrate, A support element located downstream of the rod of the aerosol generating substrate, comprising a first hollow tubular element having an inner diameter D1 and defining a cavity in the longitudinal direction that provides an unrestricted flow channel, An aerosol cooling element located downstream of the support element, comprising a second hollow tubular element having an inner diameter D2 of at least 6 mm and defining a cavity in the longitudinal direction that provides an unrestricted flow channel, An aerosol-generating article in which the ratio of the inner diameter D2 of the second hollow tubular element to the inner diameter D1 of the first hollow tubular element is at least 1.

8.

2. The aerosol generating article according to claim 1, wherein the second hollow tubular element of the aerosol cooling element has a wall thickness of less than 0.5 millimeters.

3. The aerosol generating article according to claim 1 or 2, wherein the first hollow tubular element of the support element has an inner diameter D1 of less than 5.5 mm.

4. The aerosol generating article according to any one of claims 1 to 3, wherein the first hollow tubular element of the support element has a wall thickness of at least 2 millimeters.

5. The aerosol generating article according to any one of claims 1 to 4, wherein the aerosol cooling element further comprises a ventilation zone positioned along the second hollow tubular element.

6. The aerosol generating article according to any one of claims 1 to 5, wherein the second hollow tubular element of the aerosol cooling element is a paper tube containing a plurality of overlapping layers of paper.

7. The aerosol generating article according to claim 6, wherein the plurality of layers are spirally wound around the longitudinal axis of the second hollow tubular element.

8. The aerosol generating article according to claim 5 or 6, wherein the paper tube has a hydrophobic coating layer on its inner surface.

9. The aerosol generating article according to any one of claims 5 to 8, wherein the paper tube comprises one or more layers of a first paper material and one or more layers of a second paper material, and the thickness of the second paper material is greater than the thickness of the first paper material.

10. The aerosol generating article according to any one of claims 1 to 9, wherein the length of the aerosol cooling element is less than 10 millimeters.

11. The aerosol generating article according to any one of claims 1 to 10, wherein the length of the support element is at least 6 millimeters.

12. The aerosol generating article according to any one of claims 1 to 11, further comprising an elongated susceptor element within the rod of the aerosol generating substrate.

13. The aerosol generating article according to any one of claims 1 to 12, further comprising an upstream element provided upstream of the rod of the aerosol generating substrate.

14. The aerosol generating article according to any one of claims 1 to 13, further comprising a mouthpiece element downstream of the aerosol cooling element, wherein the mouthpiece element comprises at least one mouthpiece filter segment formed from a fibrous filter material.

15. An aerosol generating system comprising an aerosol generating article according to any one of claims 1 to 14, and an aerosol generating device comprising a device cavity for receiving the aerosol generating article and at least one heating element provided around or near the heating chamber.