Aerosol-generating system comprising aerosol-generating article for producing inhaled aerosol when heating and aerosol-generating device

Abstract

FIELD: aerosol generating product.SUBSTANCE: aerosol generating product which comprises a rod of aerosol generating substrate. The aerosol generating product comprises an air conducting element adjacent to the rod of the aerosol generating substrate. The air conducting element comprises a main portion containing a core portion and a peripheral portion. The core portion comprises one or more internal air passages, while the peripheral portion comprises one or more external air passages. The total cross-sectional area of one or more outer air passages is greater than the total cross-sectional area of one or more inner air passages. The aerosol generating product further comprises a ventilation zone that allows the fluid to enter an external air passage outside the article.EFFECT: product is provided for producing an inhalable aerosol upon heating.14 cl, 8 dwg

Description

[0001] The present invention relates to an aerosol-generating article comprising an aerosol-generating substrate and adapted to produce an inhalable aerosol upon heating. The present disclosure also relates to an aerosol-generating system comprising such an aerosol-generating article.

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

[0003] A number of prior art documents disclose aerosol-generating devices for consuming aerosol-generating articles. Such devices include, for example, electrically heated aerosol-generating devices in which the aerosol is generated by transferring heat from one or more electrical heating elements of the aerosol-generating device to an aerosol-generating substrate of the heated aerosol-generating article. For example, electrically heated aerosol-generating devices have been proposed that include an internal heating plate that is adapted for insertion into an aerosol-generating substrate. The use of an aerosol-generating article in combination with an external heating system is also known.For example, document WO 2020 / 115151 describes the provision of one or more heating elements located around the periphery of an aerosol-generating article when the aerosol-generating article is contained within a cavity of an aerosol-generating device. Alternatively, document WO 2015 / 176898 proposed inductively heated aerosol-generating articles comprising an aerosol-generating substrate and a susceptor located within the aerosol-generating substrate.

[0004] Aerosol-generating products that heat the tobacco-containing substrate rather than combust it pose a number of challenges that don't arise with conventional smoking products. First, tobacco-containing substrates are typically heated to significantly lower temperatures than those reached by the combustion front in a conventional cigarette. This can impact the release of nicotine from the tobacco-containing substrate and the delivery of nicotine to the consumer. At the same time, if heating temperatures are increased in an attempt to enhance nicotine delivery, the generated aerosol typically needs to be cooled to a greater extent and more quickly before reaching the consumer.However, technical solutions widely used to cool the mainstream smoke in conventional smoking products, such as providing a highly efficient filtration segment at the mouth end of a cigarette, can have undesirable effects on aerosol-generating products in which the tobacco-containing substrate is heated rather than burned, as they can reduce nicotine delivery. Accordingly, it would be beneficial to develop new aerosol-generating products that can consistently deliver a fast and satisfying aerosol to the consumer.

[0005] Secondly, there is a general need for aerosol-generating products that are easy to use and have improved usability. For example, it would be desirable to provide an aerosol-generating product that can be easily inserted into the heating cavity of an aerosol-generating device and that can be securely held within the heating cavity so as to prevent it from slipping during use.

[0006] Therefore, it would be desirable to provide a new and improved aerosol-generating article adapted to achieve at least one of the desired results described above. Furthermore, it would be desirable to provide one such aerosol-generating article that can be manufactured efficiently and at high speed, preferably with a satisfactory RTD and low RTD variability from one article to another.

[0007] The present 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 comprise an air-conducting element upstream or downstream of the rod of the aerosol-generating substrate. The aerosol-generating article may comprise an air-conducting element adjacent to the rod of the aerosol-generating substrate. The air-conducting element may comprise a main portion comprising a core portion and a peripheral portion. The core portion may comprise one or more internal air passages, while the peripheral portion may comprise one or more external air passages. The total cross-sectional area of ​​one or more external air passages may be greater than the total cross-sectional area of ​​one or more internal air passages.

[0008] The present 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 comprise a downstream section extending downstream of the rod of the aerosol-generating substrate. The downstream section may comprise an air-conducting element. The downstream air-conducting element may be adjacent to the rod of the aerosol-generating substrate. The downstream air-conducting element may comprise a main portion comprising a core portion and a peripheral portion. The core portion may comprise one or more internal air passages, while the peripheral portion may comprise one or more external air passages.The total cross-sectional area of ​​one or more external air passages may be greater than the total cross-sectional area of ​​one or more internal air passages.

[0009] The present 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 comprise an upstream section extending upstream of the rod of the aerosol-generating substrate. The upstream section may comprise an air-conducting element. The upstream air-conducting element may be adjacent to the rod of the aerosol-generating substrate. The upstream air-conducting element may comprise a main portion comprising a core portion and a peripheral portion. The core portion may comprise one or more internal air passages, while the peripheral portion may comprise one or more external air passages.The total cross-sectional area of ​​one or more external air passages may be greater than the total cross-sectional area of ​​one or more internal air passages.

[0010] The total cross-sectional area of ​​one or more air passages may refer to the sum of the cross-sectional areas of each of the air passages. The core portion may represent the central portion of the main portion. One or more internal air passages may represent one or more central air passages. One or more external air passages may represent one or more peripheral air passages.

[0011] The present invention relates to an aerosol-generating article. The aerosol-generating article comprises a rod of an aerosol-generating substrate. The aerosol-generating article comprises an air-conducting element adjacent to the rod of the aerosol-generating substrate. The air-conducting element comprises a main portion comprising a core portion and a peripheral portion. The core portion comprises one or more internal air passages, while the peripheral portion comprises one or more external air passages. The total cross-sectional area of ​​one or more external air passages is greater than the total cross-sectional area of ​​one or more internal air passages.

[0012] The total cross-sectional area of ​​one or more air passages may refer to the sum of the cross-sectional areas of each of the air passages. The core portion may represent the central portion of the main portion. One or more internal air passages may represent one or more central air passages.

[0013] Furthermore, the present disclosure relates to an aerosol-generating system comprising an aerosol-generating article described herein and an aerosol-generating device, wherein the aerosol-generating device comprises a heating chamber for containing the aerosol-generating article and a heating element located in or along the periphery of the heating chamber. The heating element may be an external heater.

[0014] The aerosol-generating articles according to the present disclosure provide an improved configuration that has a direct impact on increasing the rate and efficiency of aerosol generation, especially when the aerosol-generating article is heated from the outside. The rate of aerosol generation indicates how quickly an aerosol can be generated. This is due to the provision of an air conduction element with one or more external air passages upstream or downstream of the aerosol-generating substrate. One or more external air passages of the air conduction element can facilitate air flow through the peripheral portion of the aerosol-generating substrate. When heated externally, the outer peripheral layer of the substrate can be heated first and, therefore, can be the first part of the substrate to be the source of aerosol generation during the initial stages of the article's heating cycle.By aligning one or more outer air passages and the resulting outer air flow with such outer peripheral portion of the substrate, any air drawn toward or away from the aerosol-generating substrate may be directed toward or drawn away from such outer peripheral layer of the substrate.

[0015] An upstream air conducting member positioned upstream of the aerosol generating substrate preferably focuses air intake on the peripheral portion of the substrate as described above, while also providing a barrier against any unintentional release of residual substrate material through the upstream end of the aerosol generating article during consumption and transport.

[0016] A downstream air passage element, positioned downstream of the aerosol-generating substrate, preferably facilitates the flow of incoming air through the outer periphery of the substrate. The downstream air passage element further provides improved cooling due to the proximity of one or more outer air passages to the outer portion or periphery of the aerosol-generating article, thereby ensuring heat transfer from the outer portion of the aerosol-generating article in addition to the material of the air passage element itself. Accordingly, the present invention promotes rapid aerosol nucleation and aerosol delivery to the user, especially during the initial stages of consumption of the externally heated article.

[0017] Furthermore, the provision of an air conduction element having outer air passages that generally have a larger cross-sectional area than the inner air passages provided in the air conduction element allows air to be directed toward or away from the aerosol-generating substrate, while providing an auxiliary air flow through the core portion of the air conduction element. Since the core portion is preferably the central portion of the air conduction element, the inner air passage can further provide air flow toward or away from more central regions of the aerosol-generating substrate.

[0018] In particular, when the aerosol-generating substrate is heated externally, it may take relatively longer to heat the central portion of the substrate. Consequently, the aerosol can be generated from this central portion during the final stages of product consumption. As a result, the combination of external and internal air passages preferentially delivers air to and from the peripheral and central regions of the substrate, thereby preferentially covering the various stages of the substrate heating cycle and ensuring improved and consistent aerosol delivery to the consumer. The large cross-sectional area of ​​the external air passages ensures that the aerosol is generated consistently and quickly during the initial stages of the heating cycle, when the peripheral portion of the substrate is heated when the product is placed in the external heating chamber.

[0019] The outer air passages of the upstream air conduction element focus the air intake on the periphery of the substrate, while the outer air passages of the downstream air conduction element promote aerosol drawing through and away from the periphery.

[0020] Additionally, an air passage element, either upstream or downstream, can also provide a barrier to prevent any particles or residues from the aerosol-generating substrate from unintentionally escaping or transferring to other components of the aerosol-generating product. The outer and inner air passages can be sized and shaped to make it difficult for such particles of the aerosol-generating substrate to pass through them.

[0021] As used in this document, the term "length" means the longitudinal dimension of a component, device, or article from the farthest upstream point of the component or the farthest point to the farthest downstream point of the component or the nearest point.

[0022] In the context of this document, the term "longitudinal" refers to the direction corresponding to the principal longitudinal axis of a component, device, or article, which passes between the opposite upstream and downstream ends of the component, device, or article. The term "transverse" is used to describe the direction perpendicular to the longitudinal direction. In the context of this document, the term "section" (in other words, "cross-section") may be used to describe the cross-section of a component, device, or article perpendicular to the longitudinal direction.

[0023] For the purposes of this document, the terms "upstream" and "downstream" describe the relative positions of elements or parts of elements, a component, device, or article with respect to the direction in which air may be drawn through the component, device, or article during use. During use or consumption, air may be drawn through an aerosol-generating article in a longitudinal direction.

[0024] As mentioned above, the aerosol-generating article according to the present invention comprises a rod of an aerosol-generating substrate. Furthermore, the aerosol-generating article according to the present invention comprises one or more elements provided downstream of the aerosol-generating substrate. The one or more elements located downstream of the rod of the aerosol-generating substrate form a downstream section of the aerosol-generating article. Additionally, the aerosol-generating article according to the present invention comprises an element provided upstream of the aerosol-generating substrate. The element located upstream of the rod of the aerosol-generating substrate defines an upstream section of the aerosol-generating article.

[0025] The aerosol generating substrate rod is preferably surrounded by a wrapper such as ficella.

[0026] The aerosol-generating substrate rod preferably has a length of at least about 8 millimeters. Preferably, the aerosol-generating substrate rod has a length of at least about 9 millimeters. More preferably, the aerosol-generating substrate rod has a length of at least about 10 millimeters.

[0027] For example, the aerosol-generating substrate rod preferably has a length of about 8 millimeters to about 16 millimeters, or about 9 millimeters to about 15 millimeters, or about 10 millimeters to about 14 millimeters. The aerosol-generating substrate rod may have a length of about 12 millimeters.

[0028] Preferably, the ratio of the length of the aerosol-generating substrate rod to the total length of the aerosol-generating article is at least about 0.15, more preferably at least about 0.2, most preferably at least about 0.22.

[0029] Preferably, the ratio of the length of the aerosol-generating substrate rod to the total length of the aerosol-generating article is less than or equal to about 0.35, more preferably less than or equal to about 0.33, more preferably less than or equal to about 0.3.

[0030] The ratio of the length of the aerosol generating substrate rod to the total length of the aerosol generating article is preferably approximately 0.25.

[0031] The aerosol generating substrate rod preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol generating article.

[0032] The "outer diameter of the aerosol-generating substrate rod" may be calculated as the average value of multiple measurements of the diameter of the aerosol-generating substrate rod taken at different locations along the length of the aerosol-generating substrate rod.

[0033] Preferably, the aerosol-generating substrate rod has an outer diameter of at least about 5 millimeters. More preferably, the aerosol-generating substrate rod has an outer diameter of at least about 6 millimeters. Even more preferably, the aerosol-generating substrate rod has an outer diameter of at least about 7 millimeters.

[0034] The aerosol-generating substrate rod preferably has an outer diameter of less than or equal to approximately 12 millimeters. More preferably, the aerosol-generating substrate rod has an outer diameter of less than or equal to approximately 10 millimeters. Even more preferably, the aerosol-generating substrate rod has an outer diameter of less than or equal to approximately 8 millimeters.

[0035] In general, it has been observed that the smaller the diameter of the aerosol-generating substrate rod, the lower the temperature required to raise the core temperature of the aerosol-generating substrate rod, so that sufficient quantities of vaporizable compounds are released from the aerosol-generating substrate to form the desired amount of aerosol. At the same time, without being limited by theory, it should be understood that a smaller diameter of the aerosol-generating substrate rod ensures that the heat supplied to the aerosol-generating article more quickly penetrates into the entire volume of the aerosol-generating substrate. However, when the diameter of the aerosol-generating substrate rod is too small, the volume-to-surface ratio of the aerosol-generating substrate becomes less favorable, since the amount of available aerosol-generating substrate decreases.

[0036] The diameter of the aerosol-generating substrate rod within the ranges described herein is particularly advantageous in terms of the balance between energy consumption and aerosol delivery. This advantage is particularly noticeable when an aerosol-generating article comprising an aerosol-generating substrate rod having a diameter as described herein is used in combination with an external heater located along the periphery of the aerosol-generating article. It has been observed that under such operating conditions, less thermal energy is required to achieve a sufficiently high temperature in the core of the aerosol-generating substrate rod and in the core of the article as a whole. Thus, when operating at low temperatures, the desired target temperature in the core of the aerosol-generating substrate can be achieved within a desirably reduced time frame and with lower energy consumption.

[0037] The aerosol-generating substrate rod may have an outer diameter of about 5 millimeters to about 12 millimeters, preferably about 6 millimeters to about 12 millimeters, more preferably about 7 millimeters to about 12 millimeters. The aerosol-generating substrate rod may have an outer diameter of about 5 millimeters to about 10 millimeters, preferably about 6 millimeters to about 10 millimeters, more preferably about 7 millimeters to about 10 millimeters. The aerosol-generating substrate rod has an outer diameter of about 5 millimeters to about 8 millimeters, preferably about 6 millimeters to about 8 millimeters, more preferably about 7 millimeters to about 8 millimeters.

[0038] Preferably, the aerosol-generating substrate rod has an outer diameter of less than approximately 7.5 millimeters. As an example, the aerosol-generating substrate rod may have an outer diameter of approximately 7.2 millimeters.

[0039] Preferably, the aerosol-generating substrate rod has a substantially constant cross-section along its length. Particularly preferably, the aerosol-generating substrate rod has a substantially circular cross-section.

[0040] In the aerosol-generating article according to the present invention, the ratio between the length of the aerosol-generating substrate rod and the total length of the aerosol-generating article may be less than or equal to approximately 0.60. Preferably, the ratio between the length of the aerosol-generating substrate rod and the total length of the aerosol-generating article may be less than or equal to approximately 0.50. More preferably, the ratio between the length of the aerosol-generating substrate rod and the total length of the aerosol-generating article may be less than or equal to approximately 0.40. Even more preferably, the ratio between the length of the aerosol-generating substrate rod and the total length of the aerosol-generating article may be less than or equal to approximately 0.30.

[0041] In the aerosol-generating article according to the present invention, the ratio between the length of the rod of the aerosol-generating substrate and the total length of the aerosol-generating article may be at least about 0.10. Preferably, the ratio between the length of the rod of the aerosol-generating substrate and the total length of the aerosol-generating article may be at least about 0.15. More preferably, the ratio between the length of the rod of the aerosol-generating substrate and the total length of the aerosol-generating article may be at least about 0.20. Preferably, the ratio between the length of the rod of the aerosol-generating substrate and the total length of the aerosol-generating article may be at least about 0.25.

[0042] The ratio between the length of the rod of the aerosol-generating substrate and the total length of the aerosol-generating article may be from about 0.10 to about 0.60, preferably from about 0.15 to about 0.60, more preferably from about 0.20 to about 0.60, even more preferably from about 0.25 to about 0.60. The ratio between the length of the rod of the aerosol-generating substrate and the total length of the aerosol-generating article may be from about 0.10 to about 0.50, preferably from about 0.15 to about 0.50, more preferably from about 0.20 to about 0.50, even more preferably from about 0.25 to about 0.50.The ratio between the length of the aerosol-generating substrate rod and the total length of the aerosol-generating article may be from about 0.10 to about 0.40, preferably from about 0.15 to about 0.40, more preferably from about 0.20 to about 0.40, even more preferably from about 0.25 to about 0.40. As an example, the ratio between the length of the aerosol-generating substrate rod and the total length of the aerosol-generating article may be from about 0.25 to about 0.30, preferably about 0.27.

[0043] Preferably, the density of the aerosol-generating substrate is at least about 150 mg per cubic centimeter. More preferably, the density of the aerosol-generating substrate is at least about 175 mg per cubic centimeter. More preferably, the density of the aerosol-generating substrate is at least about 200 mg per cubic centimeter. Even more preferably, the density of the aerosol-generating substrate is at least about 250 mg per cubic centimeter.

[0044] Preferably, the density of the aerosol-generating substrate is less than or equal to about 500 mg per cubic centimeter. More preferably, the density of the aerosol-generating substrate is less than or equal to about 450 mg per cubic centimeter. More preferably, the density of the aerosol-generating substrate is less than or equal to about 400 mg per cubic centimeter. Even more preferably, the density of the aerosol-generating substrate is less than or equal to about 350 mg per cubic centimeter.

[0045] For example, the density of the aerosol-generating substrate is preferably from about 150 mg per cubic centimeter to about 500 mg per cubic centimeter, preferably from about 175 mg per cubic centimeter to about 450 mg per cubic centimeter, more preferably from about 200 mg per cubic centimeter to about 400 mg per cubic centimeter, even more preferably from 250 mg per cubic centimeter to 350 mg per cubic centimeter. The density of the aerosol-generating substrate is preferably 300 mg per cubic centimeter.

[0046] The aerosol-generating substrate rod preferably comprises shredded tobacco material, such as tobacco cut filler, having a density of about 150 mg per cubic centimeter to about 500 mg per cubic centimeter, preferably from about 175 mg per cubic centimeter to about 450 mg per cubic centimeter, more preferably from about 200 mg per cubic centimeter to about 400 mg per cubic centimeter, more preferably from about 250 mg per cubic centimeter to about 350 mg per cubic centimeter, most preferably about 300 mg per cubic centimeter.

[0047] The RTD of the aerosol-generating substrate rod is preferably less than or equal to about 10 millimeters of water. More preferably, the RTD of the aerosol-generating substrate rod is less than or equal to about 9 millimeters of water. Even more preferably, the RTD of the aerosol-generating substrate rod is less than or equal to about 8 millimeters of water.

[0048] The RTD of the aerosol-generating substrate rod is preferably at least about 4 millimeters of water column. More preferably, the RTD of the aerosol-generating substrate rod is at least about 5 millimeters of water column. Even more preferably, the RTD of the aerosol-generating substrate rod is at least about 6 millimeters of water column.

[0049] The RTD of the aerosol-generating substrate rod may be from about 4 millimeters of water to about 10 millimeters of water, preferably from about 5 millimeters of water to about 10 millimeters of water, preferably from about 6 millimeters of water to about 25 millimeters of water. The RTD of the aerosol-generating substrate rod may be from about 4 millimeters of water to about 20 millimeters of water, preferably from about 5 millimeters of water to about 18 millimeters of water, preferably from about 6 millimeters of water to about 16 millimeters of water. The RTD of the aerosol-generating substrate rod may be from about 4 millimeters of water. to about 15 millimeters of water, preferably from about 5 millimeters of water to about 14 millimeters of water, more preferably from about 6 millimeters of water.up to approximately 12 millimeters of water column.

[0050] The aerosol-generating substrate may be a solid aerosol-generating substrate. The aerosol-generating substrate preferably comprises an aerosol-forming agent. The aerosol-forming agent may be any suitable known compound or mixture of compounds that, when used, facilitates the formation of a dense and stable aerosol. The aerosol-forming agent may provide the aerosol with substantial resistance to thermal degradation at temperatures typically encountered during use of the aerosol-generating article. Suitable aerosol-forming agents are, for example: polyhydric alcohols, such as, for example, triethylene glycol, 1,3-butanediol, propylene glycol and glycerol; esters of polyhydric alcohols, such as, for example, glycerol mono-, di- or triacetate; aliphatic esters of mono-, di- or polycarboxylic acids, such as, for example, dimethyl dodecanedioate and dimethyl tetradecanedioate; and combinations thereof.

[0051] Preferably, the aerosol forming agent comprises one or more of glycerin and propylene glycol. The aerosol forming agent may consist of glycerin or propylene glycol, or a combination of glycerin and propylene glycol.

[0052] Preferably, the aerosol-generating substrate contains at least 5 percent by weight of the aerosol-forming substance, based on the dry weight of the aerosol-generating substrate. In other words, the aerosol-generating substrate has an aerosol-forming substance content of at least 5 percent by dry weight. The aerosol-generating substrate may contain at least 7 percent by weight of the aerosol-forming substance, based on the dry weight of the aerosol-generating substrate. The aerosol-generating substrate may contain at least 10 percent by weight of the aerosol-forming substance, based on the dry weight of the aerosol-generating substrate. The aerosol-generating substrate may contain at least 12 percent by weight of the aerosol-forming substance, based on the dry weight of the aerosol-generating substrate.The aerosol-generating substrate may contain at least 13 percent by weight of an aerosol-forming agent based on the dry weight of the aerosol-generating substrate.

[0053] The aerosol-generating substrate may contain less than or exactly 22 percent by weight of the aerosol-forming agent, based on the dry weight of the aerosol-generating substrate. The aerosol-generating substrate may contain less than or exactly 19 percent by weight of the aerosol-forming agent, based on the dry weight of the aerosol-generating substrate. The aerosol-generating substrate may contain less than or exactly 16 percent by weight of the aerosol-forming agent, based on the dry weight of the aerosol-generating substrate.

[0054] The aerosol generating substrate may contain from 10 percent to 22 percent by weight based on the dry weight of the aerosol generating substrate, more preferably the amount of the aerosol forming substance is from 12 percent to 19 percent by weight based on the dry weight of the aerosol generating substrate, most preferably, for example, the amount of the aerosol forming substance is from 13 percent to 16 percent by weight based on the dry weight of the aerosol generating substrate.

[0055] The aerosol-generating substrate may contain shredded tobacco material. For example, the shredded tobacco material may be in the form of cut filler. The shredded tobacco material may be in the form of a shredded sheet of homogenized tobacco material.

[0056] In the context of this technical description, the term "cut filler" is used to describe a mixture of ground plant material, such as tobacco plant material, including, in particular, one or more of leaf blades, processed stems and veins, homogenized plant material.

[0057] The amount of the aerosol forming agent is preferably at least 5% by weight based on the dry weight of the cut filler, preferably 10% to 22% by weight based on the dry weight of the cut filler, more preferably the amount of the aerosol forming agent is 12% to 19% by weight based on the dry weight of the cut filler, for example, the amount of the aerosol forming agent is 13% to 16% by weight based on the dry weight of the cut filler. When the aerosol forming agent is added to the cut filler in the amounts described above, the cut filler can become relatively sticky.This primarily helps to hold the cut filler in place within the product, as the cut filler particles tend to adhere to surrounding cut filler particles, as well as to surrounding surfaces (e.g., the inner surface of the wrapper surrounding the cut filler).

[0058] The target amount of aerosol-forming agent can be approximately 13 percent or 18 percent by weight, based on the dry weight of the cut filler. The most effective amount of aerosol-forming agent will also depend on the cut filler, whether the cut filler contains plant leaf blades or homogenized plant material. For example, among other factors, the type of cut filler will determine the extent to which the aerosol-forming agent can facilitate the release of substances from the cut filler.

[0059] For these reasons, an aerosol-generating substrate rod containing cut filler, as described above, is capable of efficiently generating sufficient aerosol quantities at relatively low temperatures. Temperatures of 150 to 200 degrees Celsius in the heating chamber may be sufficient for such cut filler alone to generate sufficient aerosol quantities, whereas aerosol-generating devices using sheets of molded tobacco leaf typically employ temperatures of approximately 250 degrees Celsius.

[0060] An additional benefit of operating at lower temperatures is that the need for aerosol cooling is reduced. Since low temperatures are typically used, a simpler cooling function may be sufficient. This, in turn, allows for a simpler and less complex design of the aerosol-generating device.

[0061] The aerosol generating substrate may comprise homogenized plant material, preferably homogenized tobacco material.

[0062] As used herein, the term "homogenized plant material" encompasses any plant material formed by agglomerating plant particles. For example, sheets or webs of homogenized tobacco material for aerosol-generating substrates according to the present invention can be formed by agglomerating tobacco material particles obtained by grinding, milling, or crushing the plant material and, optionally, one or more of the lamellae of a tobacco leaf and the veins of a tobacco leaf. The homogenized plant material can be obtained by casting, extrusion, papermaking, or any other suitable methods known in the art.

[0063] The homogenized plant material may be provided in any suitable form.

[0064] The homogenized plant material may be in the form of one or more sheets. As used herein, the term "sheet" in relation to the present invention describes a layered element having a width and length that are substantially greater than its thickness.

[0065] The homogenized plant material may be in the form of multiple balls or granules.

[0066] The homogenized plant material may be in the form of multiple strands, strips, or pieces. For the purposes of this document, the term "strand" describes an elongated element of material whose length significantly exceeds its width and thickness. The term "strand" should be understood to encompass strips, pieces, and any other homogenized plant material of similar shape. The strands of homogenized plant material may be formed from a sheet of homogenized plant material, for example, by cutting or dividing it into pieces, or by other methods, such as extrusion.

[0067] The filaments may be formed in situ in the aerosol-generating substrate by separating or splitting a sheet of homogenized plant material during the formation of the aerosol-generating substrate, for example, by corrugating. The filaments of homogenized plant material within the aerosol-generating substrate may be separated from one another. Each filament of homogenized plant material in the aerosol-generating substrate may be at least partially connected to an adjacent filament or filaments along the length of the filaments. For example, adjacent filaments may be connected via one or more fibers. This may occur, for example, if the filaments were formed by separating a sheet of homogenized plant material during the production of the aerosol-generating substrate, as described above.

[0068] The homogenized plant material may be a homogenized tobacco material containing tobacco particles. The sheets of such homogenized tobacco material may have a tobacco content of at least about 40 percent by weight on a dry weight basis, more preferably at least about 50 percent by weight on a dry weight basis, more preferably at least about 70 percent by weight on a dry weight basis, and most preferably at least about 90 percent by weight on a dry weight basis.

[0069] For the purposes of the present invention, the term "tobacco particles" describes particles of any plant belonging to the genus Nicotiana. The term "tobacco particles" encompasses ground or powdered tobacco leaf lamellas, ground or powdered tobacco leaf stems, tobacco dust, tobacco fines, and other particulate tobacco by-products generated during the processing, handling, and shipping of tobacco. All tobacco particles are preferably substantially derived from tobacco leaf lamellas. In contrast, separated nicotine and nicotine salts are compounds derived from tobacco, but are not considered tobacco particles for the purposes of the present invention and are not included in the percentage of particulate plant material.

[0070] The homogenized plant material may further comprise one or more aerosol forming agents. After vaporization, the aerosol forming agent may carry other vaporized compounds released from the aerosol-generating substrate upon heating, such as nicotine and flavorings, in the aerosol. Aerosol forming agents suitable for inclusion in the homogenized plant material are known in the art and include, but are not limited to: polyhydric alcohols such as triethylene glycol, propylene glycol, 1,3-butanediol, and glycerol; esters of polyhydric alcohols such as glycerol mono-, di-, or triacetate; and aliphatic esters of mono-, di-, or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate.

[0071] The homogenized plant material may have an aerosol forming substance content of from about 5 percent to about 30 percent by weight on a dry weight basis, such as from about 10 percent to about 25 percent by weight on a dry weight basis or from about 15 percent to about 20 percent by weight on a dry weight basis. The aerosol forming substance may act as a humectant in the homogenized plant material.

[0072] As noted above, the aerosol-generating substrate rod may be surrounded by a wrapper. The wrapper surrounding the aerosol-generating substrate rod may be a paper wrapper or a non-paper wrapper. Paper wrappers suitable for use in the present invention are known in the art and include, but are not limited to, cigarette paper and filter papers. Non-paper wrappers suitable for use in the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco materials.

[0073] The paper wrapper may have a grammage of at least 15 g / m2, preferably at least 20 g / m2. The paper wrapper may have a grammage of less than or equal to 35 g / m2, preferably less than or equal to 30 g / m2. The paper wrapper may have a grammage of 15 g / m2 to 35 g / m2, preferably from 20 g / m2 to 30 g / m2. The paper wrapper may have a grammage of 25 g / m2. The paper wrapper may have a thickness of at least 25 micrometers, preferably at least 30 micrometers, more preferably at least 35 micrometers. The paper wrapper may have a thickness of less than or equal to 55 micrometers, preferably less than or equal to 50 micrometers, and more preferably less than or equal to 45 micrometers. The paper wrapper may have a thickness of between 25 micrometers and 55 micrometers, preferably between 30 micrometers and 50 micrometers, and more preferably between 35 micrometers and 45 micrometers.The paper wrapper can be as thin as 40 microns.

[0074] The wrapper may be formed from a laminated material containing multiple layers. Preferably, the wrapper is formed from a multilayer sheet containing a layer of aluminum. The use of a multilayer sheet containing aluminum advantageously prevents combustion of the aerosol-generating substrate if the aerosol-generating substrate is intended to be ignited rather than heated.

[0075] The paper layer of the multi-layer sheet may have a grammage of at least 35 g / m 2 , preferably at least 40 g / m 2 The paper layer of a multilayer sheet may have a grammage that is less than or equal to 55 g / m 2 , preferably less than or equal to 50 g / m 2 The paper layer of a multilayer sheet can have a grammage from 35 to 55 g / m 2 , preferably from 40 g / m 2 up to 50 g / m 2The paper layer of a multilayer sheet can have a grammage of 45 g / m 2 .

[0076] The paper layer of the multilayer sheet may have a thickness of at least 50 micrometers, preferably at least 55 micrometers, more preferably at least 60 micrometers. The paper layer of the multilayer sheet may have a thickness of less than or equal to 80 micrometers, preferably less than or equal to 75 micrometers, more preferably less than or equal to 70 micrometers.

[0077] The paper layer of the multilayer sheet may have a thickness of 50 micrometers to 80 micrometers, preferably 55 micrometers to 75 micrometers, and more preferably 60 micrometers to 70 micrometers. The paper layer of the multilayer sheet may have a thickness of 65 micrometers.

[0078] The metal layer of the multilayer sheet may have a grammage of at least 12 g / m 2 , preferably at least 15 g / m 2The metal layer of a multilayer sheet may have a grammage that is less than or equal to 25 g / m 2 , preferably less than or equal to 20 g / m 2 The metal layer of a multilayer sheet can have a grammage of 12 g / m 2 up to 25 g / m 2 , preferably from 15 to 20 g / m 2 The metal layer of a multilayer sheet can have a grammage of 17 g / m 2 .

[0079] The metal layer of the multilayer sheet may have a thickness of at least 2 micrometers, preferably at least 3 micrometers, more preferably at least 5 micrometers. The metal layer of the multilayer sheet may have a thickness of less than or equal to 15 micrometers, preferably less than or equal to 12 micrometers, more preferably less than or equal to 10 micrometers.

[0080] The metal layer of the multilayer sheet may have a thickness of 2 micrometers to 15 micrometers, preferably 3 micrometers to 12 micrometers, and more preferably 5 micrometers to 10 micrometers. The metal layer of the multilayer sheet may have a thickness of 6 microns.

[0081] The wrapper surrounding the aerosol-generating substrate core can be a paper wrapper containing PVOH (polyvinyl alcohol) or silicon. The addition of PVOH (polyvinyl alcohol) or silicon can improve the wrapper's grease barrier properties.

[0082] PVOH or silicon can be applied to the paper layer as a surface coating, for example, located on the outer surface of the paper layer of the wrapper surrounding the rod of the aerosol-generating substrate. PVOH or silicon can be located on the outer surface of the paper layer of the wrapper and form a layer thereon. PVOH or silicon can be located on the inner surface of the paper layer of the wrapper. PVOH or silicon can be located on the inner surface of the paper layer of the aerosol-generating article and form a layer thereon. PVOH or silicon can be located on the inner surface and the outer surface of the paper layer of the wrapper. PVOH or silicon can be located on the inner surface and the outer surface of the paper layer of the wrapper and form a layer thereon.

[0083] The paper wrapper containing PVOH or silicon may have a grammage of at least 20 g / m2, preferably at least 25 g / m 2, more preferably at least 30 g / m 2 Paper wrappers containing PVOH or silicon may have a grammage that is less than or equal to 50 g / m 2 , preferably less than or equal to 45 g / m 2 , more preferably less than or equal to 40 g / m 2 Paper wrappers containing PVOH or silicon can have a grammage of 20 to 50 g / m 2 , preferably from 25 to 45 g / m 2 , more preferably from 30 to 40 g / m 2 Paper wrapper containing PVOH or silicon may have a grammage of approximately 35 g / m 2 .

[0084] The paper wrapper containing PVOH or silicon may have a thickness of at least 25 micrometers, preferably at least 30 micrometers, more preferably at least 35 micrometers. The paper wrapper containing PVOH or silicon may have a thickness that is less than or equal to 50 micrometers, preferably less than or equal to 45 micrometers, more preferably less than or equal to 40 micrometers. The paper wrapper containing PVOH or silicon may have a thickness of 25 micrometers to 50 micrometers, preferably from 30 micrometers to 45 micrometers, more preferably from 35 micrometers to 40 micrometers. The paper wrapper containing PVOH or silicon may have a thickness of 37 micrometers.

[0085] As mentioned in this disclosure, the present invention preferably comprises at least one air conduction element or segment. A downstream section of the aerosol-generating article may comprise an air conduction element. Such an air conduction element may be referred to as a downstream air conduction element, an aerosol cooling element, or a support element.

[0086] The upstream section of the aerosol-generating article may include an air-conducting element. Such an air-conducting element may be referred to as an upstream air-conducting element, an upstream element, or a front plug.

[0087] Each of the upstream section and the downstream section of the aerosol-generating article may comprise an air-conducting element. The features described in this disclosure with respect to the air-conducting element may, respectively, be applied to the downstream air-conducting element (in other words, the air-conducting element that is located downstream of the aerosol-generating substrate rod) and to the upstream air-conducting element (in other words, the air-conducting element that is located upstream of the aerosol-generating substrate rod).

[0088] The upstream air conduction element may be adjacent to the rod of the aerosol-generating substrate. The upstream air conduction element may be adjacent to the upstream end of the rod of the aerosol-generating substrate. The upstream air conduction element may be located upstream of the rod of the aerosol-generating substrate. The upstream air conduction element may be located at the upstream end of the aerosol-generating article.

[0089] The downstream air conduction element may be adjacent to the aerosol-generating substrate rod. The downstream air conduction element may be adjacent to the downstream end of the aerosol-generating substrate rod. The downstream air conduction element may be located downstream of the aerosol-generating substrate rod. The downstream air conduction element may be located between the aerosol-generating substrate rod and any other component or element of the downstream section, such as a hollow tubular element or a mouthpiece element. The downstream air conduction element may be adjacent to the mouthpiece element.The downstream air-conducting element may be adjacent to the upstream end of the mouthpiece element. The downstream air-conducting element may be positioned upstream of the downstream end of the aerosol-generating article.

[0090] The air conduction element according to the present disclosure may comprise a main portion. The main portion of the air conduction element may comprise a core portion and a peripheral portion. The core and peripheral portions may extend longitudinally. The peripheral portion may surround or limit the core portion. The main portion is preferably a cylindrical main portion having a substantially circular cross-section.

[0091] The core portion may comprise the center of the main portion of the air conduction element. The core portion of the main portion preferably refers to a circular core portion located at the center of the cross-section of the main portion.

[0092] The core portion of the main part may have a radius that is at least 25 percent of the radius of the main part. The core portion of the main part may have a radius that is at least 30 percent of the radius of the main part. The core portion of the main part may have a radius that is at least 50 percent of the radius of the main part. The core portion of the main part may have a radius that is no more than 80 percent of the radius of the main part. The core portion of the main part may have a radius that is no more than 75 percent of the radius of the main part.

[0093] The peripheral portion of the air conduction element may comprise an annular portion of the main portion surrounding the core portion. In other words, the peripheral portion may occupy the remaining cross-sectional area of ​​the main portion of the air conduction element. The peripheral portion may extend between the outer periphery or circumference of the air conduction element and the core portion.

[0094] The air conduction member may comprise an outer air passage. The outer air passage may be an external air passage. The outer air passage may be formed on the outer surface of the main portion of the air conduction member. The outer air passage may refer to an air passage located away from the central axis of the air conduction member. The outer air passage may be an internal air passage located within the material or main portion of the air conduction member, or an external air passage provided on the outer surface of the air conduction member. The outer air passage may be referred to as a peripheral air passage. The outer air passage may extend from one end of the air conduction member to the other end of the air conduction member.The outer air passage may extend from an upstream end of the air conducting member to a downstream end of the air conducting member.

[0095] The outer air passage may be an inner air passage. The outer air passage may be formed within the main portion of the air conduction member. The outer air passage may be formed on the periphery of the main portion of the air conduction member or within it. The outer air passage may be an inner passage or channel extending along the air conduction member.

[0096] The air conduction element may comprise one or more outer air passages. The air conduction element may comprise at least two outer air passages, preferably at least three outer air passages, more preferably at least four outer air passages. The outer air passages may be uniformly or equally distributed within the air conduction element. The outer air passages may be uniformly or equally distributed around the core portion of the air conduction element. The outer air passages, either in the form of an internal cavity, an air passage, or an outer air passage, preferably extend from the upstream end of the air conduction element to the downstream end of the air conduction element.The external air passages, either in the form of an internal cavity or an air passage or an external air passage, preferably extend continuously from the upstream end of the air conducting member to the downstream end of the air conducting member.

[0097] The outer air passage may comprise a groove formed on the outer surface of the air conduction member. The air conduction member may comprise at least one groove. The air conduction member may comprise at least two grooves, preferably at least three grooves, more preferably at least four grooves, and even more preferably at least five grooves. The grooves may be uniformly or equally distributed around the core portion of the air conduction member. The grooves may be uniformly or equally distributed around the main portion of the air conduction member.

[0098] Any outer air passage, inner air passage, or groove of the air conducting member may extend from one end of the air conducting member to the other end of the air conducting member. Any outer air passage, inner air passage, or groove of the air conducting member may extend from the upstream end of the air conducting member to the downstream end of the air conducting member. Any outer air passage, inner air passage, or groove of the air conducting member may extend continuously from the upstream end of the air conducting member to the downstream end of the air conducting member.Any outer air passage, inner air passage or groove of the air conducting element may freely extend from an upstream end of the air conducting element to a downstream end of the air conducting element such that air or aerosol may flow directly from end to end of the air conducting element.

[0099] Providing multiple external air passages, such as grooves or internal channels, increases the flow of air or aerosol through the periphery of the air conduction element and, possibly, through the periphery of the aerosol-generating substrate, thereby increasing heat exchange and improving aerosol nucleation. In particular, in the context of a downstream air conduction element, providing external air passages, preferably in the form of grooves, can improve the heat exchange of the aerosol flowing through the external air passages due to the proximity of the aerosol to the outer portion of the aerosol-generating article.

[0100] Each outer air passage may extend or follow a substantially rectilinear path. Each outer air passage may be substantially parallel to each other. Each outer air passage may extend along a substantially helical path. Each groove may extend along a helical path around the air conduction element or along its outer surface. By extending or following a helical path, the outer air passage can effectively follow a longer path from the upstream end of the air conduction element to the downstream end, thereby providing more time for aerosol cooling. Each groove may extend along a sinusoidal path or any other waveform. The waveform may include a square wave, a triangle wave, or a sawtooth wave.

[0101] Each outer air passage may be defined by an internal cavity extending along the air conduction element. The outer air passage, which extends within the main portion of the air conduction element, may have a substantially circular cross-section. The radius of such an internal passage may be at least approximately 0.25 mm, preferably at least approximately 0.5 mm, and more preferably at least approximately 1 mm. The radius of such an internal passage may be no more than approximately 2 mm.

[0102] When an outer or peripheral air passage is formed within the material of the air conductive member, the outer air passage may be located at a distance from the periphery of the air conductive member. When an outer or peripheral air passage is formed within the material of the air conductive member, each outer air passage may be located at a distance from the periphery of the air conductive member. Such a distance may be no more than about 2 mm, preferably no more than about 1.5 mm, more preferably no more than about 1 mm, and even more preferably no more than about 0.75 mm. Such a distance preferably refers to the distance measured from the outer edge of the outer air passage to the farthest edge or periphery of the air conductive member.

[0103] The depth of the outer air passage defined by the groove may be at least approximately 0.5 mm. The depth of the outer air passage defined by the groove may be at least approximately 0.7 mm. The depth of the outer air passage defined by the groove may be at least approximately 1 mm. The depth of the outer air passage defined by the groove may be no less than approximately 1.5 mm. The depth of the outer air passage defined by the groove may be no more than approximately 2 mm.

[0104] The ratio of the total cross-sectional area of ​​the outer air passages (in other words, the sum of all outer air passages) to the total cross-sectional area of ​​the air conducting element may be at least about 2.5 percent. Such a ratio may be at least about 5 percent, preferably at least about 10 percent, more preferably at least about 15 percent, and even more preferably at least about 25 percent. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​the air conducting element may be at least about 30 percent. The total cross-sectional area of ​​the air conducting element may refer to the internal cross-sectional area of ​​the aerosol-generating article in the position of the air conducting element.

[0105] The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​the air conduction element may be no more than approximately 60 percent. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​the air conduction element may be no more than approximately 50 percent. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​the air conduction element may be no more than approximately 40 percent. The total cross-sectional area of ​​the air conduction element may refer to the cross-sectional area of ​​the air conduction element if the air conduction element were completely solid. In other words, the total cross-sectional area of ​​the air conduction element may be based on the largest outer diameter of the air conduction element.As discussed above, the outer air passages may comprise grooves formed on the outer surface of the air conduction element. 0106. An air conduction element located either upstream or downstream may be wrapped in a wrapper. Such a wrapper may have features consistent with any of the wrappers described in this disclosure. The wrapper surrounding the air conduction element may be substantially airtight. In embodiments comprising one or more grooves on the outer surface of the air conduction element, the wrapper surrounding the air conduction element may define a boundary for one or more outer air passages, which may be defined by one or more grooves. In other words, one or more outer air passages of the air conduction element may be defined by the wrapper and one or more grooves.

[0107] In embodiments where the outer air passages are defined by one or more grooves along the periphery of the air conduction element, the outer surface of the air conduction element defined by the grooves can define a wet surface, and the outer surface of the air conduction element that is not defined by the grooves can define a non-wet surface. The term "wet surface" refers to the surface of the air conduction element that is configured to contact air or an aerosol passing through the grooves. The "non-wet surface" can contact the wrapper surrounding the air conduction element. In the present disclosure, the term "outer surface of the air conduction element" preferably refers to the outer longitudinal surface of the air conduction element, extending parallel to the longitudinal direction of the air conduction element or the aerosol-generating article.

[0108] The ratio of the wet surface area of ​​the air conduction element to the non-wet surface area of ​​the air conduction element may be at least approximately 25 percent. The ratio of the wet surface area of ​​the air conduction element to the non-wet surface area of ​​the air conduction element may be at least approximately 50 percent. The ratio of the wet surface area of ​​the air conduction element to the non-wet surface area of ​​the air conduction element may be at least approximately 1.

[0109] The ratio of the wet surface area of ​​the air conduction element to the non-wet surface area of ​​the air conduction element may be no more than approximately 3. The ratio of the wet surface area of ​​the air conduction element to the non-wet surface area of ​​the air conduction element may be no more than approximately 2.5. The ratio of the wet surface area of ​​the air conduction element to the non-wet surface area of ​​the air conduction element may be no more than approximately 2.

[0110] The core portion of the air conduction element is preferably substantially solid. This can advantageously prevent the unintentional release or movement of the aerosol-generating substrate material and facilitate the flow of air or aerosol through any air passages present in the peripheral portion of the air conduction element. In other words, the core portion of the air conduction element may not contain or define a central internal cavity extending along the air conduction element. Therefore, the outer air passages or grooves of the air conduction element may be the primary or sole paths for the movement of air or aerosol through the air conduction element toward the aerosol-generating substrate or toward the downstream end of the aerosol-generating article.

[0111] The air conduction element may comprise one or more internal air passages. The air conduction element may comprise at least two internal air passages. The core portion of the air conduction element may define one or more internal air passages. The one or more internal air passages may be surrounded by one or more external air passages. Each internal air passage may be defined as a longitudinal air channel or cavity extending along the air conduction element. Each internal air passage may extend from an upstream end of the air conduction element to a downstream end of the air conduction element.Each internal air passage may extend continuously from an upstream end of the air conducting member to a downstream end of the air conducting member.

[0112] The material of the air-conducting element may be porous. However, pores or voids characteristic of the material of the air-conducting element cannot be considered as defining one or more internal air passages or one or more external air passages of the air-conducting element. In other words, any air passages are preferably formed in the material or main part of the air-conducting element during the manufacturing stage.

[0113] The ratio of the total cross-sectional area of ​​any internal air passages to the total cross-sectional area of ​​the air conducting element may be at least approximately 1 percent (or 0.01). The ratio of the total cross-sectional area of ​​any internal air passages to the total cross-sectional area of ​​the air conducting element may be at least approximately 5 percent (or 0.05). The ratio of the total cross-sectional area of ​​any internal air passages to the total cross-sectional area of ​​the air conducting element may be at least approximately 7.5 percent (or 0.075).

[0114] The ratio of the total cross-sectional area of ​​any internal air passages to the total cross-sectional area of ​​the air conduction element may be no more than approximately 20 percent (or 0.2). The ratio of the total cross-sectional area of ​​any internal air passages to the total cross-sectional area of ​​the air conduction element may be no more than approximately 15 percent. The ratio of the total cross-sectional area of ​​any internal air passages to the total cross-sectional area of ​​the air conduction element may be no more than approximately 10 percent.

[0115] The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 0.5 percent. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 1. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 1.5. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 2.The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 3. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 4. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 5. The ratio of the total cross-sectional area of ​​the outer air passages to the total cross-sectional area of ​​any inner air passages may be at least approximately 6.

[0116] The ratio of the total cross-sectional area of ​​the external air passages to the total cross-sectional area of ​​any internal air passages may be no more than approximately 10. The ratio of the total cross-sectional area of ​​the external air passages to the total cross-sectional area of ​​any internal air passages may be no more than approximately 7.5. The ratio of the total cross-sectional area of ​​the external air passages to the total cross-sectional area of ​​any internal air passages may be no more than approximately 5.

[0117] The length of the air conduction element may be at least approximately 4 mm. The length of the air conduction element may be at least approximately 5 mm. The length of the air conduction element may be at least approximately 6 mm. The length of the air conduction element may be at least approximately 7 mm. The length of the air conduction element may be at least approximately 10 mm. The length of the air conduction element may be at least approximately 12 mm. The length of the air conduction element may be at least approximately 17 mm.

[0118] The length of the air conduction element may be less than or equal to approximately 50 mm. The length of the air conduction element may be less than or equal to approximately 25 mm. The length of the air conduction element may be less than or equal to approximately 23 mm. The length of the air conduction element may be less than or equal to approximately 20 mm. The length of the air conduction element may be less than or equal to approximately 15 mm.

[0119] The length of the air conduction element may be from about 4 mm to about 50 mm, preferably from about 4 mm to about 30 mm, more preferably from about 4 mm to about 25 mm. The length of the air conduction element may be from about 4 mm to about 50 mm, preferably from about 7 mm to about 30 mm, more preferably from about 10 mm to about 25 mm. The length of the air conduction element may be from about 12 mm to about 20 mm. The length of the air conduction element may be from about 10 mm to about 15 mm. The length of the air conduction element may be from about 17 mm to about 23 mm.

[0120] The air passage length may preferably be approximately 12 mm. The air passage length may be approximately 16 mm. The air passage length may be approximately 20 mm.

[0121] The length of the downstream air conduction element may preferably be approximately 12 mm. The length of the downstream air conduction element may be approximately 16 mm. The length of the downstream air conduction element may be approximately 20 mm.

[0122] The length of the upstream air conduction element may preferably be approximately 4 mm. The length of the upstream air conduction element may be approximately 5 mm. The length of the upstream air conduction element may be approximately 6 mm.

[0123] It is preferable that when both of the upstream air conducting member and the downstream air conducting member are provided in the same aerosol generating article, the length of the downstream air conducting member is greater than the length of the upstream air conducting member.

[0124] The air conduction element preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating substrate rod and the outer diameter of the aerosol-generating article. This ensures that any grooves or outer or inner air passages of the air conduction element are blocked at the end by the aerosol-generating substrate. In other words, the cross-section of any grooves or air passages of the air conduction element may overlap the cross-section of the aerosol-generating substrate. The cross-section of any grooves or air passages of the air conduction element may completely overlap the cross-section of the aerosol-generating substrate.The cross-section of any air grooves or passages of the air conduction member, when projected onto the aerosol generating substrate, may be within the cross-section of the aerosol generating substrate, particularly when the air conduction member and the aerosol generating substrate are assembled and aligned in the aerosol generating article.

[0125] The air duct element may have an outside diameter of 5 mm to 12 mm, for example, 5 mm to 10 mm, or 6 mm to 8 mm. The air duct element may have an outside diameter of 7.2 mm plus or minus 10 percent.

[0126] The air passage element (or its main part) can be formed by thermoforming. The grooves formed on the air passage element can also be formed by thermoforming. Thermoforming can advantageously provide a cost-effective and efficient manufacturing process for the air passage element, especially when it contains external grooves. The air passage element can be manufactured by injection molding or extrusion.

[0127] The air conduction member (or its main part) may comprise (or may be formed by) a polymer material. The air conduction member (or its main part) may comprise (or may be formed by) a plastic material. The air conduction member (or its main part) may comprise (or may be formed by) a thermoplastic material. The air conduction member (or its main part) may comprise (or may be formed by) polyethylene (PE). The air conduction member (or its main part) may comprise (or may be formed by) cellulose acetate.

[0128] The air-conducting element may comprise or be formed from a substantially impermeable material. The air-conducting element may comprise or be formed from a substantially impermeable material. The material of the air-conducting element may be substantially impermeable to air. The use of a substantially impermeable material may cause air or aerosol to flow in part exclusively through the internal or external air passages of the air-conducting element.

[0129] The air conduction element may comprise paper (or may be formed from it). The air conduction element may comprise cardboard. The air conduction element may be formed from extruded paper.

[0130] The aerosol-generating article according to the present disclosure comprises an upstream section located upstream of the aerosol-generating substrate rod. The upstream section is preferably located immediately upstream of the aerosol-generating substrate rod. The upstream section preferably extends between the upstream end of the aerosol-generating article and the aerosol-generating substrate rod.

[0131] The upstream section comprises an upstream element located upstream of the aerosol-generating substrate rod. Suitable upstream elements are described in the present disclosure. The upstream element may be an upstream element in the form of a plug (or a front plug). The upstream element may be an upstream hollow tubular element. The upstream element may be an upstream air-conducting element.

[0132] The upstream element is preferably an upstream air conduction element. The upstream air conduction element may be adjacent to the rod of the aerosol-generating substrate. The upstream air conduction element may be adjacent to the upstream end of the rod of the aerosol-generating substrate. The upstream air conduction element may be located upstream of the rod of the aerosol-generating substrate. The upstream air conduction element may be located at the upstream end of the aerosol-generating article.

[0133] Accordingly, the upstream element or the upstream air conduction element may comprise features associated with the air conduction element as described in this disclosure. Similarly, the features described herein with respect to the upstream element may also be present in the upstream air conduction element.

[0134] The upstream element advantageously prevents direct physical contact with the upstream end of the aerosol-generating substrate, in addition to the air conduction benefits associated with the air conduction element described in this disclosure. For example, if the aerosol-generating substrate comprises a susceptor element, the upstream element can prevent direct physical contact with the upstream end of the susceptor element. This helps prevent displacement or deformation of the susceptor element during handling or transportation of the aerosol-generating article. This, in turn, helps maintain the shape and position of the susceptor element.

[0135] Furthermore, having an upstream element helps prevent any loss of substrate, which can be advantageous, for example, if the substrate contains particulate plant material.

[0136] If the aerosol generating substrate contains shredded tobacco, such as cut filler tobacco, the upstream section or element thereof may further help prevent the loss of loose tobacco particles from the upstream end of the article.

[0137] The upstream section or upstream element thereof may also further provide a degree of protection for the aerosol generating substrate during storage because it covers at least to some extent the upstream end of the aerosol generating substrate that may otherwise be exposed.

[0138] For aerosol-generating articles intended to be inserted into a cavity in an aerosol-generating device so that the aerosol-generating substrate can be heated from the outside within the cavity, an upstream section or its upstream element can advantageously facilitate the insertion of the upstream end of the article into the cavity. Inclusion of the upstream element can further protect the end of the aerosol-generating substrate rod during insertion of the article into the cavity, minimizing the risk of damage to the substrate.

[0139] The upstream section or its upstream element may also provide an improved appearance to the upstream end of the aerosol-generating article. Furthermore, if desired, the upstream section or its upstream element may be used to provide information about the aerosol-generating article, such as information about the brand, flavor, content, or information about the aerosol-generating device with which the article is intended.

[0140] The upstream element may be a porous element in the form of a plug. Preferably, the upstream element has a porosity of at least approximately 50 percent in the longitudinal direction of the aerosol-generating article. More preferably, the upstream element has a porosity of from approximately 50 percent to approximately 90 percent in the longitudinal direction. The porosity of the upstream element in the longitudinal direction is determined by the ratio of the cross-sectional area of ​​the material forming the upstream element and the internal cross-sectional area of ​​the aerosol-generating article at the position of the upstream element.

[0141] The upstream element may be made of a porous material or may contain a plurality of holes. This can be achieved, for example, by laser perforation. Preferably, the plurality of holes are uniformly distributed across the cross-section of the upstream element.

[0142] The porosity or permeability of an upstream element may be advantageously designed to provide the aerosol generating article with a particular overall resistance to draw (RTD) without substantially affecting the filtration provided by other parts of the article.

[0143] The upstream element may be formed from an air-impermeable material. In such embodiments, the aerosol-generating article may be designed such that air flows into the aerosol-generating substrate rod through suitable ventilation means provided in the wrapper.

[0144] It may be desirable to minimize the RTD of an upstream element. For example, this may be the case for products intended to be inserted into the cavity of an aerosol-generating device, such that the aerosol-generating substrate is heated externally, as described in this document. For such products, it is desirable to provide the product with the lowest possible RTD so that the majority of the consumer RTD experience is provided by the aerosol-generating device, not the product.

[0145] The RTD of the upstream element is preferably less than or equal to about 10 millimeters of water column. More preferably, the RTD of the upstream element is less than or equal to about 5 millimeters of water column. Even more preferably, the RTD of the upstream element is less than or equal to about 2.5 millimeters of water column. Even more preferably, the RTD of the upstream element is less than or equal to about 2 millimeters of water column.

[0146] The RTD of the upstream element may be at least 0.1 millimeters of water, or at least about 0.25 millimeters of water, or at least about 0.5 millimeters of water.

[0147] The RTD of the upstream element may be from about 0.1 millimeters of water to about 10 millimeters of water, preferably from about 0.25 millimeters of water to about 10 millimeters of water, preferably from about 0.5 millimeters of water to about 10 millimeters of water. The RTD of the upstream element is from about 0.1 millimeters of water to about 5 millimeters of water, preferably from about 0.25 millimeters of water to about 5 millimeters of water, preferably from about 0.5 millimeters of water to about 5 millimeters of water, the RTD of the upstream element may be from about 0.1 millimeters of water to about 2.5 millimeters of water. Art., preferably from about 0.25 millimeters of water to about 2.5 millimeters of water., more preferably from about 0.5 millimeters of water column to about 2.5 millimeters of water column. The RTD of the upstream element is from about 0.1 millimeters of water column to about 2 millimeters of water column, preferably from about 0.25 millimeters of water column to about 2 millimeters of water column, more preferably from about 0.5 millimeters of water column to about 2 millimeters of water column, the RTD of the upstream element may be about 1 millimeter of water column.

[0148] The upstream element preferably has an RTD of less than about 2 millimeters of water per millimeter of length, more preferably less than about 1.5 millimeters of water per millimeter of length, more preferably less than about 1 millimeter of water per millimeter of length, more preferably less than about 0.5 millimeters of water per millimeter of length, more preferably less than about 0.3 millimeters of water per millimeter of length, more preferably less than about 0.2 millimeters of water per millimeter of length.

[0149] Preferably, the upstream section or its upstream element has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating article. Preferably, the outer diameter of the upstream section or its upstream element is from about 6 millimeters to about 8 millimeters, more preferably from about 7 millimeters to about 7.5 millimeters. Preferably, the upstream section or its upstream element has an outer diameter that is approximately 7.1 mm.

[0150] The upstream section or upstream element preferably has a length of about 2 millimeters to about 8 millimeters, more preferably from about 3 millimeters to about 7 millimeters, more preferably from about 4 millimeters to about 6 millimeters. The upstream section or upstream element may have a length of about 5 millimeters.

[0151] The length of the upstream section or upstream element may advantageously vary to achieve the desired overall length of the aerosol-generating article. For example, if it is desired to reduce the length of one of the other components of the aerosol-generating article, the length of the upstream section or upstream element may be increased to maintain the same overall length of the article.

[0152] The length of the upstream section or its upstream element can be used to control the position of the aerosol-generating article within the cavity of the aerosol-generating device for articles intended for external heating. This can advantageously ensure that the position of the aerosol-generating substrate within the cavity can be optimized for heating, as well as the position of any ventilation.

[0153] The upstream section is preferably surrounded by a wrapper, such as a filament. The wrapper surrounding the upstream section is preferably a rigid filament, for example, a filament with a basis weight of at least about 80 grams per square meter (g / m2), or at least about 100 g / m2, or at least about 110 g / m2. This provides structural rigidity to the upstream section.

[0154] The upstream section is preferably connected to the aerosol generating substrate rod and optionally to at least a portion of the downstream section via an outer wrapper.

[0155] As mentioned above, the aerosol-generating article according to the present invention comprises a downstream section located downstream of the aerosol-generating substrate rod. The downstream section is preferably located immediately downstream of the aerosol-generating substrate rod. The downstream section of the aerosol-generating article preferably extends between the aerosol-generating substrate rod and the downstream end of the aerosol-generating article. The downstream section may comprise one or more elements, each of which is described in more detail within the framework of the present disclosure.

[0156] The length of the downstream section may be at least approximately 15 mm. The length of the downstream section may be at least approximately 20 mm. The length of the downstream section may be at least approximately 24 mm. The length of the downstream section may be at least approximately 26 mm.

[0157] The length of the downstream section may be equal to or less than (in other words, not greater than) approximately 36 mm. The length of the downstream section may be equal to or less than approximately 32 mm. The length of the downstream section may be equal to or less than approximately 30 mm.

[0158] The length of the downstream section may be from approximately 15 mm to approximately 36 mm. The length of the downstream section may be from approximately 20 mm to approximately 36 mm. The length of the downstream section may be from approximately 24 mm to approximately 32 mm. The length of the downstream section may be from approximately 26 mm to approximately 30 mm.

[0159] The downstream section preferably comprises an air conduction element according to the present disclosure. The downstream air conduction element may be located downstream of the aerosol-generating substrate rod. The downstream air conduction element may be located adjacent to the aerosol-generating substrate rod. The downstream air conduction element may be adjacent to the downstream end of the aerosol-generating substrate rod.

[0160] The downstream section preferably comprises a hollow tubular element. Preferably, the downstream section comprises a mouthpiece element. The downstream section may comprise or consist of a hollow tubular element and a mouthpiece element, wherein the hollow tubular element is positioned between the aerosol-generating substrate rod and the mouthpiece element. The hollow tubular element may be adjacent to the aerosol-generating substrate rod and the mouthpiece element.

[0161] If the downstream section comprises a downstream air conduction element, the hollow tubular element may be positioned downstream of the downstream air conduction element. The hollow tubular element may be adjacent to the downstream air conduction element. The hollow tubular element may be positioned between the downstream air conduction element and the mouthpiece element.

[0162] Providing a relatively long downstream section ensures that an appropriate length of the aerosol-generating article protrudes from the aerosol-generating device when the article is inserted into it. This appropriate protrusion length ensures convenient insertion and removal of the article from the device, and also ensures that the upstream portions of the article are properly inserted into the device, reducing the risk of damage, especially during insertion.

[0163] In the context of this disclosure, the terms "hollow tubular segment" or "hollow tubular element" are used to refer to a generally elongated element that defines a lumen or passage for air flow along its longitudinal axis. In particular, the term "tubular" will be used hereinafter to refer to a tubular element that has a substantially cylindrical cross-section and that defines at least one air flow channel that establishes continuous fluid communication between an upstream end of the tubular element and a downstream end of the tubular element. However, it should be understood that alternative geometries (e.g., alternative cross-sectional shapes) of the tubular segment may be possible. The hollow tubular segment or element may be a separate, discrete element of the aerosol-generating article that has a specific length and thickness.In the present description, a “hollow tubular segment” or a “hollow tubular element” may also be referred to as a “hollow tube” or a “hollow tube-shaped segment”.

[0164] The internal volume defined by the hollow tubular element may be at least approximately 100 cubic millimeters. In other words, the volume of the cavity or lumen defined by the hollow tubular element may be at least approximately 100 cubic millimeters. Preferably, the internal volume defined by the hollow tubular element may be at least approximately 300 cubic millimeters. The internal volume defined by the hollow tubular element may be at least approximately 700 cubic millimeters.

[0165] The internal volume defined by the hollow tubular element may be less than or equal to approximately 1200 cubic millimeters. Preferably, the internal volume defined by the hollow tubular element may be less than or equal to approximately 1000 cubic millimeters. The internal volume defined by the hollow tubular element may be less than or equal to approximately 900 cubic millimeters.

[0166] The internal volume defined by the hollow tubular element may be from about 100 to about 1200 cubic millimeters. Preferably, the internal volume defined by the hollow tubular element may be from about 300 to about 1000 cubic millimeters. The internal volume defined by the hollow tubular element may be from about 700 to about 900 cubic millimeters.

[0167] In the context of the present invention, the hollow tubular segment provides a channel for unrestricted flow. This means that the hollow tubular segment provides an insignificant level of resistance to draw (RTD). The term "insignificant level of RTD" is used to describe an RTD of less than 1 mm H2O per 10 millimeters of the length of the hollow tubular segment or hollow tubular element, preferably less than 0.4 mm H2O per 10 millimeters of the length of the hollow tubular segment or hollow tubular element, more preferably less than 0.1 mm H2O per 10 millimeters of the length of the hollow tubular segment or hollow tubular element.

[0168] The RTD of the hollow tubular element is preferably less than or equal to about 10 millimeters of water column. More preferably, the RTD of the hollow tubular element is less than or equal to about 5 millimeters of water column. Even more preferably, the RTD of the hollow tubular element is less than or equal to about 2.5 millimeters of water column. Even more preferably, the RTD of the hollow tubular element is less than or equal to about 2 millimeters of water column. Even more preferably, the RTD of the hollow tubular element is less than or equal to about 1 millimeter of water column.

[0169] The RTD of the hollow tubular member may be at least 0 millimeters of water, or at least about 0.25 millimeters of water, or at least about 0.5 millimeters of water, or at least about 1 millimeter of water.

[0170] The hollow tubular element may comprise one or more hollow tubular segments. Preferably, the hollow tubular element consists of a single hollow tubular segment. Preferably, the hollow tubular element consists of a continuous hollow tubular segment. The hollow tubular segment may comprise any of the features described in this disclosure with respect to the hollow tubular element.

[0171] As will be described in this disclosure, an aerosol-generating article may comprise a ventilation zone at a location along the aerosol-generating article. In the context of a ventilation zone, the term "location" preferably refers to a longitudinal location, unless otherwise specified. The aerosol-generating article may comprise a ventilation zone at a location along a downstream section. The aerosol-generating article may comprise a ventilation zone at a location along a downstream air-conducting element. In other words, the ventilation zone may be provided at a longitudinal location along the downstream air-conducting element. The ventilation zone may be located above the downstream air-conducting element.

[0172] An aerosol-generating article may comprise a ventilation zone at a location along the hollow tubular member. This or any ventilation zone may extend through a peripheral wall of the hollow tubular member. Fluid communication is thus established between the flow path defined internally by the hollow tubular member and the external environment (in other words, the external portion of the aerosol-generating article). The ventilation zone may be provided at a longitudinal location along the downstream air-conducting element. This ventilation zone may extend through any wrapper or wrappers surrounding the air-conducting element. This ventilation zone, provided along the air-conducting element, can create fluid communication between the external portion of the aerosol-generating article and one or more external air passages (or grooves).Such a ventilation zone provided along the air conduction member may create fluid communication from the exterior of the aerosol generating article to one or more exterior air passages (or grooves).

[0173] The length of the hollow tubular element may be at least approximately 8 mm. The length of the hollow tubular element may be at least approximately 10 mm. The length of the hollow tubular element may be at least approximately 15 mm. The length of the hollow tubular element may be at least approximately 19 mm.

[0174] The length of the hollow tubular member may be less than or equal to approximately 30 mm. The length of the hollow tubular member may be less than or equal to approximately 25 mm. The length of the hollow tubular member may be less than or equal to approximately 23 mm.

[0175] The length of the hollow tubular element may be from approximately 8 mm to 30 mm. The length of the hollow tubular element may be from approximately 10 mm to 30 mm. The length of the hollow tubular element may be from approximately 15 mm to 25 mm. The length of the hollow tubular element may be from approximately 19 mm to 23 mm.

[0176] A relatively long hollow tubular element provides and defines a relatively long internal cavity within the aerosol-generating article and downstream of the aerosol-generating substrate rod. As discussed in the present disclosure, providing an empty cavity located downstream (preferably immediately downstream) of the aerosol-generating substrate enhances the nucleation of aerosol particles generated by the substrate. Providing a relatively long cavity maximizes such nucleation benefits, thereby improving aerosol formation and cooling. Providing such a hollow tubular element downstream of the downstream air-conducting element also enhances the aerosol formation and cooling benefits provided by the air-conducting element itself.

[0177] The thickness of the peripheral wall (in other words, the wall thickness) of the hollow tubular element may be at least about 100 micrometers. The wall thickness of the hollow tubular element may be at least about 150 micrometers. The wall thickness of the hollow tubular element may be at least about 200 micrometers, preferably at least about 250 micrometers, and even more preferably at least about 500 micrometers (or 0.5 mm).

[0178] The wall thickness of the hollow tubular element may be less than or equal to approximately 2 millimeters, preferably less than or equal to approximately 1.5 millimeters, and even more preferably less than or equal to approximately 1.25 millimeters. The wall thickness of the hollow tubular element may be less than or equal to approximately 1 millimeter. The wall thickness of the hollow tubular element may be less than or equal to approximately 500 micrometers.

[0179] The wall thickness of the hollow tubular member may be from about 100 micrometers to about 2 millimeters, preferably from about 150 micrometers to about 1.5 millimeters, even more preferably from about 200 micrometers to about 1.25 millimeters. The wall thickness of the hollow tubular member may preferably be about 250 micrometers (0.25 mm).

[0180] At the same time, by keeping the thickness of the peripheral wall of the hollow tubular segment relatively small, it is ensured that the total internal volume of the hollow tubular segment, which becomes available for the aerosol to begin the nucleation process immediately after the aerosol components leave the rod of the aerosol generating substrate, and the cross-sectional surface area of ​​the hollow tubular segment are effectively maximized, while at the same time it is ensured that the hollow tubular segment has the necessary structural strength to prevent the aerosol generating article from being compressed, and to provide some support for the rod of the aerosol generating substrate, and that the RTD of the hollow tubular segment is minimized.It is clear that large cross-sectional surface areas of the hollow tubular segment are associated with a decrease in the velocity of the aerosol jet moving along the aerosol-generating component, which is expected to also favor aerosol nucleation. Furthermore, when using a hollow tubular segment with a relatively thin thickness, it was found that it is possible to essentially prevent the diffusion of ventilation air before it contacts and mixes with the aerosol jet, which, as is clear, further favors nucleation phenomena. In practice, by providing more controlled, localized cooling of the jet of evaporated compounds, the effect of cooling on the formation of new aerosol particles can be enhanced.

[0181] The hollow tubular member preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating substrate rod and the outer diameter of the aerosol-generating article.

[0182] The hollow tubular element may have an outside diameter of 5 millimeters to 12 millimeters, for example, 5 millimeters to 10 millimeters, or 6 millimeters to 8 millimeters. The hollow tubular element may preferably have an outside diameter of 7.2 millimeters plus or minus 10 percent.

[0183] The hollow tubular member may have an internal diameter. Preferably, the hollow tubular member may have a constant internal diameter along the length of the hollow tubular member. However, the internal diameter of the hollow tubular member may vary along the length of the hollow tubular member.

[0184] The hollow tubular element may have an inner diameter of at least approximately 2 millimeters. For example, the hollow tubular element may have an inner diameter of at least approximately 4 millimeters, at least approximately 5 millimeters, or at least approximately 7 millimeters.

[0185] Providing a hollow tubular member having an inner diameter as specified above can advantageously ensure sufficient rigidity and strength for the hollow tubular member.

[0186] The hollow tubular element may have an internal diameter of no more than approximately 10 millimeters. For example, the hollow tubular element may have an internal diameter of no more than approximately 9 millimeters, no more than approximately 8 millimeters, or no more than approximately 7.5 millimeters.

[0187] Providing a hollow tubular member having an inner diameter as specified above can advantageously reduce the tightening resistance of the hollow tubular segment.

[0188] The hollow tubular member may have an inner diameter of from about 2 millimeters to about 10 millimeters, from about 4 millimeters to about 9 millimeters, from about 5 millimeters to about 8 millimeters, or from about 6 millimeters to about 7.5 millimeters.

[0189] The hollow tubular element may have an outer diameter of approximately 7.1 or 7.2 mm. The hollow tubular element may have an inner diameter of approximately 6.7 mm.

[0190] The hollow tubular segment may comprise a paper-based material. The hollow tubular segment may comprise at least one layer of paper. The paper may be a very rigid paper. The paper may be a corrugated paper, such as corrugated heat-resistant paper or corrugated parchment paper.

[0191] The hollow tubular element may preferably comprise cardboard. The hollow tubular element may be a cardboard tube. The hollow tubular element may be formed from cardboard. Cardboard is advantageously an economical material that provides a balance between deformability to ensure easy insertion of the article into the aerosol-generating device and sufficient rigidity to ensure proper engagement of the article within the device. Consequently, the cardboard tube can provide suitable resistance to deformation or compression during use.

[0192] The hollow tubular segment may be a paper tube. The hollow tubular segment may be formed as a tube from spirally wound paper. The hollow tubular segment may be formed from multiple layers of paper. The paper may have a basis weight of at least about 50 grams per square meter, at least about 60 grams per square meter, at least about 70 grams per square meter, or at least about 90 grams per square meter.

[0193] The hollow tubular segment may comprise a polymeric material. For example, the hollow tubular segment may comprise a polymeric film. The polymeric film may comprise a cellulose film. The hollow tubular segment may comprise low-density polyethylene (LDPE) or polyhydroxyalkanoate (PHA) fibers. The hollow tube may comprise cellulose acetate tow.

[0194] As described above, the aerosol-generating article according to the present invention comprises a downstream section comprising a hollow tubular element provided downstream of the aerosol-generating substrate rod and adjacent to the downstream end of the aerosol-generating substrate rod. Furthermore, the aerosol-generating article according to the present invention comprises a ventilation zone at a location along the hollow tubular element. The aerosol-generating article according to the present invention may comprise a ventilation zone at a location along the downstream air-conducting element.

[0195] Thus, a ventilated cavity is provided downstream of the aerosol-generating substrate rod, either in the form of a ventilated groove or external air passage of an air-conducting element, or in the form of a ventilated internal cavity of a hollow tubular element. This offers several potential technical advantages.

[0196] First, the inventors of the present invention discovered that a single ventilated hollow tubular element or air-conducting element provides particularly effective aerosol cooling. Thus, satisfactory aerosol cooling can be achieved even with a relatively short downstream section. This is particularly desirable, as it enables the provision of an aerosol-generating article wherein the aerosol-generating substrate (and, in particular, the tobacco-containing substrate) is heated rather than burned, thereby combining satisfactory aerosol delivery with effective aerosol cooling to temperatures desired by the consumer.

[0197] Secondly, the inventors unexpectedly discovered that such rapid cooling of the volatile compounds released during heating of the aerosol-generating substrate promotes improved nucleation of aerosol particles. This effect is particularly noticeable when, as will be described in more detail below, the ventilation zone is located at a precisely defined location downstream of the aerosol-generating substrate rod. Indeed, the inventors discovered that the beneficial effect of enhanced nucleation can significantly counteract the potentially less desirable dilution effects caused by the introduction of ventilation air.

[0198] Similarly, a ventilation zone can provide similar benefits by placing an air conduction element along a downstream location and providing ventilation at that location.

[0199] The ventilation zone may typically comprise a plurality of perforations in the peripheral wall of the hollow tubular element. The ventilation zone may typically comprise a plurality of perforations extending through the peripheral wall of the hollow tubular element. The ventilation zone may extend through the material of the air-conducting element to provide fluid communication between any external air passages (which may not be grooves provided on the outer surface of the air-conducting element) and the outer portion of the aerosol-generating article. Thus, the ventilation zone may comprise a plurality of perforations extending through the material of the air-conducting element to provide fluid communication between any external air passages and the outer portion of the aerosol-generating article.

[0200] The ventilation zone may comprise a plurality of perforations through the wrapper surrounding the air-conducting element. The ventilation zone may comprise a plurality of perforations extending through the wrapper surrounding the air-conducting element. The ventilation zone may comprise a plurality of perforations extending through the material of the air-conducting element to provide fluid communication with one or more external air passages. Benefits equivalent to those of a ventilation zone provided along a hollow tubular element are achieved by having a ventilation zone provided along a downstream air-conducting element, but in the context of an aerosol-generating article, which may not comprise a hollow tubular element.A ventilation zone along the air-conducting element may provide fluid communication with the outer air passages or grooves of the air-conducting element, through which the aerosol stream can be transported. Such a ventilation zone, provided along the air-conducting element, may create fluid communication between the outer portion of the aerosol-generating article and one or more outer air passages. Such a ventilation zone, provided along the air-conducting element, may create fluid communication from the outer portion of the aerosol-generating article to one or more outer air passages.Such ventilation zone may extend through the material of the air conducting member to provide fluid communication between any external air passages (which may not be grooves provided on the outer surface of the air conducting member) and the exterior of the aerosol generating article.

[0201] The ventilation zone preferably comprises at least one annular row of perforations. The ventilation zone may comprise two annular rows of perforations. For example, the perforations may be formed on a production line during the manufacturing of an aerosol-generating article. Preferably, each annular row of perforations comprises from 8 to 30 perforations.

[0202] The aerosol generating article according to the present invention may have a ventilation level of at least about 2 percent.

[0203] The term "ventilation level" is used throughout this description to denote the volumetric ratio between the airflow admitted into the aerosol-generating article through the ventilation zone (ventilation airflow) and the sum of the aerosol-containing airflow and the ventilation airflow. The higher the ventilation level, the greater the dilution of the aerosol flow delivered to the consumer. The aerosol-generating article preferably has a ventilation level of at least 5 percent, more preferably at least 10 percent, even more preferably at least 12 percent, or at least 15 percent.

[0204] The aerosol-generating article according to the present invention may have a ventilation level of up to approximately 90 percent. Preferably, the aerosol-generating article according to the present invention has a ventilation level that is less than or equal to 80 percent, more preferably less than or equal to 70 percent, even more preferably less than or equal to 60 percent, and most preferably less than or equal to 50 percent.

[0205] Without being limited by theory, the inventors of the present invention have found that a temperature difference caused by the admission of cooler external air into a hollow tubular member or a downstream air-conducting member (in particular, external air passages or grooves thereof) through a ventilation zone can have an advantageous effect on the nucleation and growth of aerosol particles.

[0206] The formation of an aerosol from a gaseous mixture containing various chemical compounds depends on the subtle interactions of nucleation, evaporation, condensation, and droplet coalescence, while simultaneously accounting for changes in concentration, temperature, and vapor velocity fields. The so-called classical nucleation theory is based on the assumption that the fraction of molecules in the gas phase is large enough to remain cohesive for a long time with sufficient probability (e.g., 0.5 in 1). These molecules represent a kind of critical threshold molecular clusters among transient molecular aggregates, meaning that, on average, smaller molecular clusters are more likely to disintegrate quickly into the gas phase, while larger clusters are, on average, more likely to grow.This critical cluster is identified as the key nucleation core, from which droplet growth is expected due to the condensation of molecules from the vapor. It is assumed that the initial droplets, which have just formed, begin with a certain diameter and can then grow by several orders of magnitude. This process is simplified and can be accelerated by rapid cooling of the surrounding vapor, which causes condensation. In this regard, it should be remembered that evaporation and condensation are two sides of the same mechanism, namely, mass transfer between gas and liquid. While evaporation refers to the net mass transfer from liquid droplets to the gas phase, condensation is the net mass transfer from the gas phase to the droplet phase. Evaporation (or condensation) will cause a decrease in droplet volume (or growth) but will not change the number of droplets.

[0207] In this scenario, which may be further complicated by droplet coalescence, temperature and cooling rate may play a significant role in determining the system's response. In general, different cooling rates may result in significantly different temporal behavior regarding liquid phase (droplet) formation, as the nucleation process is typically nonlinear. Without being limited by theory, it is hypothesized that cooling may cause a rapid decrease in droplet number concentration, followed by a strong, short-term increase in droplet growth (nucleation burst). This nucleation burst may be more significant at lower temperatures. Furthermore, it may be that higher cooling rates may promote an earlier onset of nucleation. Conversely, a decrease in the cooling rate may have a beneficial effect on the final size attained by aerosol droplets.

[0208] Therefore, the rapid cooling caused by admitting external air into the hollow tubular member or a downstream air-conducting element (in particular, external air passages or grooves) through the ventilation zone can be beneficially utilized to promote the nucleation and growth of aerosol droplets. However, at the same time, the immediate disadvantage of admitting external air into the hollow tubular member or a downstream air-conducting element (in particular, external air passages or grooves) is the dilution of the aerosol stream delivered to the consumer.

[0209] The present inventors have unexpectedly discovered how the beneficial effect of improved nucleation, achieved by rapid cooling caused by the introduction of ventilation air into the article, can significantly counteract the less desirable effects of dilution. Thus, satisfactory aerosol delivery values ​​are consistently achieved by aerosol-generating articles according to the present invention.

[0210] The present inventors also unexpectedly found that the effect of dilution on the aerosol, which can be assessed by measurement, in particular the effect on the delivery of an aerosol forming substance (e.g., glycerol) contained in an aerosol generating substrate, is advantageously minimized when the ventilation level is within the ranges described above.

[0211] In particular, it was found that ventilation levels of 10 percent to 20 percent and even more preferably 12 to 18 percent lead to particularly satisfactory glycerol delivery values.

[0212] This is particularly advantageous for "short" aerosol-generating articles, such as articles in which the length of the aerosol-generating substrate rod is less than about 40 millimeters, preferably less than 30 millimeters, even more preferably less than 25 millimeters, and especially preferably less than 20 millimeters, or in which the overall length of the aerosol-generating article is less than about 70 millimeters, preferably less than about 60 millimeters, and even more preferably less than 50 millimeters. It should be understood that in such aerosol-generating articles, there is typically little time and space for the aerosol to form and for the particulate phase of the aerosol to be available for delivery to the consumer, and therefore the benefits of the improved nucleation described above are felt particularly significantly.

[0213] The distance between the ventilation zone and the downstream end of the aerosol-generating article may be at least 10 millimeters. Preferably, the distance between the ventilation zone and the downstream end of the aerosol-generating article is at least 12 millimeters. More preferably, the distance between the ventilation zone and the downstream end of the aerosol-generating article is at least 15 millimeters.

[0214] The distance between the ventilation zone and the downstream end of the aerosol-generating article is preferably less than or equal to 21 millimeters. More preferably, the distance between the ventilation zone and the downstream end of the aerosol-generating article is less than or equal to 19 millimeters. Even more preferably, the distance between the ventilation zone and the downstream end of the aerosol-generating article is less than or equal to 17 millimeters.

[0215] The distance between the ventilation zone and the downstream end of the aerosol-generating article may be from 10 millimeters to 21 millimeters, preferably from 12 millimeters to 21 millimeters, more preferably from 15 millimeters to 21 millimeters. The distance between the ventilation zone and the downstream end of the aerosol-generating article may be from 10 millimeters to 19 millimeters, preferably from 12 millimeters to 19 millimeters, more preferably from 15 millimeters to 19 millimeters. The distance between the ventilation zone and the downstream end of the aerosol generating article may be from 10 millimeters to 17 millimeters, preferably from 12 millimeters to 17 millimeters, more preferably from 15 millimeters to 17 millimeters.

[0216] The ventilation zone can be arranged along the downstream air conduction element. The distance between the ventilation zone and the downstream end of the downstream air conduction element is preferably less than or equal to 10 millimeters. The distance between the ventilation zone and the downstream end of the downstream air conduction element is preferably less than or equal to 7 millimeters. The distance between the ventilation zone and the downstream end of the downstream air conduction element is preferably less than or equal to 5 millimeters. The distance between the ventilation zone and the downstream end of the downstream air conduction element is preferably less than or equal to 3 millimeters.The ventilation zone is preferably located along the downstream half of the downstream air conduction element.

[0217] The advantage of arranging the ventilation zone at a distance from the downstream end of the aerosol-generating article within the ranges described above is that it generally ensures that during use, when the aerosol-generating article is partially contained within the heating device, the portion of the aerosol-generating article extending beyond the heating device is of sufficient length to allow the user to comfortably hold the article between their lips. At the same time, the data indicate that if the length of the portion of the aerosol-generating article extending beyond the heating device were greater, the aerosol-generating article could easily be unintentionally and undesirably bent, which could impair the delivery of the aerosol or the overall intended use of the aerosol-generating article.

[0218] As discussed in this disclosure, the downstream section may comprise a mouthpiece element. The mouthpiece element may extend from the downstream end of the downstream section. The mouthpiece element may be located at the downstream end of the aerosol-generating article. The downstream end of the mouthpiece element may define the downstream end of the aerosol-generating article. The mouthpiece element may be adjacent to the air-conducting element. Thus, a hollow tubular element may not be provided.

[0219] A mouthpiece element may be provided downstream of the aerosol-generating substrate rod. The mouthpiece element may extend all the way to the mouthpiece end of the aerosol-generating article. The mouthpiece element may comprise at least one filtering mouthpiece segment formed from a fibrous filter material. The mouthpiece element may be positioned downstream of the hollow tubular element described above. The mouthpiece element may extend between the hollow tubular element and the downstream end of the aerosol-generating article.

[0220] The parameters or characteristics described in relation to the mouthpiece element may generally be equally applied to the mouthpiece filter segment of the mouthpiece element.

[0221] The fibrous filter material can be used to filter an aerosol generated from an aerosol-generating substrate. Suitable fibrous filter materials will be known to those skilled in the art. Particularly preferably, at least one filter segment of the mouthpiece comprises a cellulose acetate filter segment formed from cellulose acetate tow.

[0222] The mouthpiece element may consist of a single filtering mouthpiece segment. The mouthpiece element may comprise two or more filtering mouthpiece segments, axially aligned with each other and in end-to-end contact.

[0223] The downstream section may comprise a mouthpiece end cavity at the downstream end, downstream of the mouthpiece element, as described above. The mouthpiece end cavity may be defined by an additional hollow tubular element provided at the downstream end of the mouthpiece. The mouthpiece end may be defined by an outer wrapper of the aerosol-generating article, wherein the outer wrapper extends in a direction downstream of (or past) the mouthpiece element.

[0224] The mouthpiece may optionally contain a flavoring agent, which may be provided in any suitable form. For example, the mouthpiece may contain one or more capsules, beads, or granules of flavoring agent, or one or more threads or fibers filled with a flavoring agent.

[0225] Preferably, the mouthpiece element or its mouthpiece filter segment has low particle filtration efficiency.

[0226] The mouthpiece is preferably surrounded by a wick. Preferably, the mouthpiece is not ventilated so that air does not enter the aerosol-generating article along the mouthpiece.

[0227] The mouthpiece element is preferably connected to one or more adjacent upstream components of the aerosol generating article via a rim wrap.

[0228] The mouthpiece element preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating article. The diameter of the mouthpiece element (or filter segment of the mouthpiece) may be substantially the same as the outer diameter of the hollow tubular element. As mentioned in this disclosure, the outer diameter of the hollow tubular element may be approximately 7.2 mm, plus or minus 10 percent.

[0229] The diameter of the mouthpiece may be from approximately 5 mm to approximately 10 mm. The diameter of the mouthpiece may be from approximately 6 mm to approximately 8 mm. The diameter of the mouthpiece may be from approximately 7 mm to approximately 8 mm. The diameter of the mouthpiece may be approximately 7.2 mm, plus or minus 10 percent. The diameter of the mouthpiece may be approximately 7.25 mm, plus or minus 10 percent.

[0230] Unless otherwise specified, the resistance to draw (RTD) of an aerosol-generating component or article is measured in accordance with ISO 6565-2015. RTD refers to the pressure required to force air through the entire length of the component. The terms "pressure drop" or "resistance to draw" of a component or article may also refer to "resistance to draw." Such terms generally refer to measurements in accordance with ISO 6565-2015, which are typically performed under test conditions at a volumetric flow rate of approximately 17.5 milliliters per second at the outlet or downstream end of the component being measured, at a temperature of approximately 22 degrees Celsius, a pressure of approximately 101 kPa (approximately 760 Torr), and a relative humidity of approximately 60%.

[0231] The resistance to draw (RTD) of the downstream section may be at least approximately 0 mmH2O. The RTD of the downstream section may be at least approximately 3 mmH2O. The RTD of the downstream section may be at least approximately 6 mmH2O.

[0232] The RTD of the downstream section may be no more than approximately 12 mmH2O. The RTD of the downstream section may be no more than approximately 11 mmH2O. The RTD of the downstream section may be no more than approximately 10 mmH2O.

[0233] The resistance to draw (RTD) of the mouthpiece element may be at least approximately 0 mmH2O. The RTD of the mouthpiece element may be at least approximately 3 mmH2O. The RTD of the mouthpiece element may be at least approximately 6 mmH2O.

[0234] The RTD of the mouthpiece element may be no more than approximately 12 mmH2O. The RTD of the mouthpiece element may be no more than approximately 11 mmH2O. The RTD of the mouthpiece element may be no more than approximately 10 mmH2O.

[0235] As mentioned above, the mouthpiece element or filter segment of the mouthpiece may be formed from a fibrous material. The mouthpiece element may be formed from a porous material. The mouthpiece element may be formed from a biodegradable material. The mouthpiece element may be formed from a cellulosic material, such as cellulose acetate. For example, the mouthpiece element may be formed from a bundle of cellulose acetate fibers having a denier per fiber of from about 10 to about 15. For example, the mouthpiece element is formed from a relatively low-density cellulose acetate tow, such as a cellulose acetate tow containing fibers of approximately 12 denier per fiber.

[0236] The mouthpiece element can be formed from a polylactic acid-based material. The mouthpiece element can be formed from a bioplastic material, preferably a starch-based bioplastic material. The mouthpiece element can be manufactured by injection molding or extrusion. Bioplastic-based materials are advantageous because they can provide mouthpiece structures that are simple and inexpensive to manufacture with a specific and complex cross-sectional profile. These structures can contain multiple relatively large airflow channels passing through the mouthpiece material, ensuring suitable RTD characteristics.

[0237] The mouthpiece element may be formed from a sheet of suitable material that has been corrugated, pleated, gathered, woven, or folded into an element that defines multiple longitudinally extending channels. Such a sheet of suitable material may be formed from paper, cardboard, a polymer such as polylactic acid, or any other cellulose-based material, paper-based material, or bioplastic-based material. The cross-sectional profile of such a mouthpiece element may exhibit randomly oriented channels.

[0238] The mouthpiece element may be formed by any other suitable method. For example, the mouthpiece element may be formed from a bundle of longitudinally extending tubes. The longitudinally extending tubes may be formed from polylactic acid. The mouthpiece element may be formed by extrusion, molding, lamination, injection, or milling of a suitable material. Thus, it is preferable to have a small pressure drop (or RTD) from the upstream end of the mouthpiece element to the downstream end of the mouthpiece element.

[0239] The length of the mouthpiece element may be at least approximately 3 mm. The length of the mouthpiece element may be at least approximately 5 mm. The length of the mouthpiece element may be equal to or less than approximately 15 mm. The length of the mouthpiece element may be equal to or less than approximately 11 mm. The length of the mouthpiece element may range from approximately 3 mm to approximately 15 mm. The length of the mouthpiece element may range from approximately 5 millimeters to approximately 11 millimeters.

[0240] The length of the mouthpiece element is preferably approximately 7 mm. The length of the mouthpiece element is preferably approximately 8 mm. The length of the mouthpiece element is preferably approximately 9 mm.

[0241] The aerosol generating article may have an overall length of from approximately 35 millimeters to approximately 100 millimeters.

[0242] Preferably, the overall length of the aerosol-generating article according to the present invention is at least about 35 millimeters. The overall length of the aerosol-generating article according to the present invention is at least about 38 millimeters. More preferably, the overall length of the aerosol-generating article according to the present invention is at least about 40 millimeters. Even more preferably, the overall length of the aerosol-generating article according to the present invention is at least about 42 millimeters.

[0243] The overall length of the aerosol-generating article according to the present invention is preferably less than or equal to 70 millimeters. More preferably, the overall length of the aerosol-generating article according to the present invention is preferably less than or equal to 60 millimeters. Even more preferably, the overall length of the aerosol-generating article according to the present invention is preferably less than or equal to 50 millimeters.

[0244] The overall length of the aerosol-generating article is preferably from about 38 millimeters to about 70 millimeters, more preferably from about 40 millimeters to about 70 millimeters, even more preferably from about 42 millimeters to about 70 millimeters. The overall length of the aerosol-generating article is preferably from about 38 millimeters to about 60 millimeters, more preferably from about 40 millimeters to about 60 millimeters, even more preferably from about 42 millimeters to about 60 millimeters. The overall length of the aerosol-generating article is preferably from about 38 millimeters to about 50 millimeters, more preferably from about 40 millimeters to about 50 millimeters, even more preferably from about 42 millimeters to about 50 millimeters.The overall length of the aerosol generating product may be approximately 45 millimetres.

[0245] The aerosol-generating article has an outer diameter of at least 5 millimeters. Preferably, the aerosol-generating article has an outer diameter of at least 6 millimeters. More preferably, the aerosol-generating article has an outer diameter of at least 7 millimeters.

[0246] Preferably, the aerosol-generating article has an outer diameter of less than or equal to approximately 12 millimeters. More preferably, the aerosol-generating article has an outer diameter of less than or equal to approximately 10 millimeters. Even more preferably, the aerosol-generating article has an outer diameter of less than or equal to approximately 8 millimeters.

[0247] The aerosol-generating article may have an outer diameter of about 5 millimeters to about 12 millimeters, preferably from about 6 millimeters to about 12 millimeters, more preferably from about 7 millimeters to about 12 millimeters. The aerosol-generating article may have an outer diameter of about 5 millimeters to about 10 millimeters, preferably from about 6 millimeters to about 10 millimeters, more preferably from about 7 millimeters to about 10 millimeters. The aerosol-generating article may have an outer diameter of about 5 millimeters to about 8 millimeters, preferably from about 6 millimeters to about 8 millimeters, more preferably from about 7 millimeters to about 8 millimeters.

[0248] The outer diameter of the aerosol-generating article may be substantially constant along the entire length of the article. Alternatively, different parts of the aerosol-generating article may have different outer diameters.

[0249] The aerosol-generating article according to the present invention may comprise a rod of an aerosol-generating substrate and a downstream section located downstream of the rod of the aerosol-generating substrate. The downstream section may comprise a downstream air-conducting element and a mouthpiece element. The downstream air-conducting element may be located between the rod of the aerosol-generating substrate and the mouthpiece element. The downstream air-conducting element may correspond to the air-conducting element described in this disclosure. All components may be assembled in an axial, sequential, and abutting manner within the wrapper of the aerosol-generating article.The aerosol generating article may comprise a ventilation zone provided at a location along the downstream air flow element.

[0250] An aerosol-generating article according to the present invention may comprise a rod of an aerosol-generating substrate and a downstream section located downstream of the rod of the aerosol-generating substrate. The downstream section may comprise a downstream air-conducting element and a mouthpiece element. The downstream air-conducting element may be located between the rod of the aerosol-generating substrate and the mouthpiece element. The downstream air-conducting element may correspond to the air-conducting element described in this disclosure. All components may be assembled in an axial, sequential, and abutting manner within the wrapper of the aerosol-generating article.The downstream section may also comprise a hollow tubular element located between the downstream air-conducting element and the mouthpiece element. The aerosol-generating article may also comprise an upstream section located upstream of the aerosol-generating substrate rod. The upstream section comprises an upstream element. The upstream element may comprise a plug-shaped element or a hollow tubular element, as described herein. The aerosol-generating article may comprise a ventilation zone provided at a location along the hollow tubular element or the downstream air-conducting element.

[0251] The aerosol-generating article according to the present invention may comprise a rod of an aerosol-generating substrate, a downstream section located downstream of the rod of the aerosol-generating substrate, and an upstream section located upstream of the rod of the aerosol-generating substrate. The downstream section may comprise a hollow tubular element and a mouthpiece element. The upstream section may comprise an upstream air-conducting element. The hollow tubular element may be located between the rod of the aerosol-generating substrate and the mouthpiece element. The upstream air-conducting element may correspond to the air-conducting element described in the present disclosure.All components may be assembled axially, sequentially, or adjacently within the wrapper of the aerosol-generating article. The downstream section may also contain a downstream air-conducting element positioned between the aerosol-generating substrate core and the hollow tubular element. The aerosol-generating article may contain a ventilation zone located along the hollow tubular element or the downstream air-conducting element.

[0252] The aerosol-generating article according to the present invention may comprise a rod of an aerosol-generating substrate, a downstream section located downstream of the rod of the aerosol-generating substrate, and an upstream section located upstream of the rod of the aerosol-generating substrate. The downstream section may comprise a downstream air-conducting element and a mouthpiece element. The upstream section may comprise an upstream air-conducting element. The downstream air-conducting element may be located between the rod of the aerosol-generating substrate and the mouthpiece element.The upstream air-conducting element and the downstream air-conducting element may correspond to the air-conducting element described in this disclosure. All components may be assembled in an axial, sequential, and abutting manner within the wrapper of the aerosol-generating article. The downstream section may also comprise a hollow tubular element positioned between the downstream air-conducting element and the mouthpiece element. The aerosol-generating article may comprise a ventilation zone provided at a location along the hollow tubular element or the downstream air-conducting element.

[0253] As discussed above, the present disclosure also relates to an aerosol-generating system comprising an aerosol-generating device having a distal end and a mouthpiece end. The aerosol-generating device may comprise a main portion. The main portion or housing of the aerosol-generating device may define a cavity of the device for removably receiving an aerosol-generating article at the mouthpiece end of the device. The aerosol-generating device may comprise a heating element or heater for heating an aerosol-generating substrate when the aerosol-generating article is received within the cavity of the device.

[0254] The cavity of the device may be referred to as the heating chamber of the aerosol-generating device. The cavity of the device may extend between the distal end and the mouthpiece, or near end. The distal end of the cavity of the device may be a closed end, and the mouthpiece, or near end of the cavity of the device may be an open end. An aerosol-generating article can be inserted into the cavity of the device, or heating chamber, through the open end of the cavity of the device. The cavity of the device may be cylindrical in shape to match the shape of the aerosol-generating article.

[0255] The term "contained within" may refer to the fact that a component or element is fully or partially contained within another component or element. For example, the term "an aerosol-generating article contained within a cavity of a device" refers to an aerosol-generating article that is fully or partially contained within the cavity of the device of the aerosol-generating article. When an aerosol-generating article is contained within a cavity of a device, the aerosol-generating article may be adjacent to the distal end of the cavity of the device. When an aerosol-generating article is contained within a cavity of a device, the aerosol-generating article may be in substantial proximity to the distal end of the cavity of the device. The distal end of the cavity of the device may be defined by an end wall.

[0256] The length of the device cavity may be from approximately 10 mm to approximately 50 mm. The length of the device cavity may be from approximately 20 mm to approximately 40 mm. The length of the device cavity may be from approximately 25 mm to approximately 30 mm.

[0257] The length of the cavity of the device (or heating chamber) may be the same as or greater than the length of the rod of the aerosol-generating substrate. The length of the cavity of the device may be the same as or greater than the sum of the lengths of the upstream section or element and the rod of the aerosol-generating substrate. The length of the cavity of the device may be such that the downstream section or a portion thereof is configured to protrude from the cavity of the device when the aerosol-generating article is contained within the cavity of the device. The length of the cavity of the device may be such that a portion of the downstream section (e.g., a hollow tubular element or a mouthpiece element) is configured to protrude from the cavity of the device when the aerosol-generating article is contained within the cavity of the device.The length of the cavity of the device may be such that a portion of a downstream section (e.g., a hollow tubular element or a mouthpiece element) is configured to be contained within the cavity of the device when the aerosol generating article is contained within the cavity of the device.

[0258] At least 25 percent of the length of the downstream section can be inserted or accommodated within the cavity of the device when the aerosol-generating article is inserted within the device. At least 30 percent of the length of the downstream section can be inserted or accommodated within the cavity of the device when the aerosol-generating article is inserted within the device.

[0259] Optimizing the quantity or length of the article inserted into the aerosol-generating device can improve the article's resistance to accidental dislodgment during use. Specifically, when the aerosol-generating substrate is heated, the substrate can contract so that its outer diameter can decrease, thereby reducing the degree to which the inserted portion of the article inserted into the device can frictionally engage with the device cavity. The inserted portion of the article or the portion of the article configured to fit within the device cavity can have the same length as the device cavity.

[0260] The length of the cavity of the device is preferably from about 25 mm to about 29 mm. More preferably, the length of the cavity of the device is from about 26 mm to about 29 mm. Even more preferably, the length of the cavity of the device is from about 27 mm to about 28 mm.

[0261] Preferably, the combined length of the upstream section (or element) and the inserted portion of the downstream section is equivalent to a range of approximately 80 percent to approximately 120 percent of the length of the protruding portion of the aerosol-generating article. The inserted portion of the downstream section, or the hollow tubular element, or the aerosol-generating article refers to a portion of the downstream section, or the hollow tubular element, or the aerosol-generating article, which is configured to be located within the cavity of the device when the aerosol-generating article is housed therein. The protruding portion of the aerosol-generating article refers to an article that is configured to be located outside the cavity of the device or to protrude from the device when the aerosol-generating article is housed therein.The inventors of the present invention have discovered that this ratio minimizes the risk of the article unintentionally exiting the device during use, especially after possible shrinkage of the article during use. The portion of the aerosol-generating article configured to be inserted into the device is preferably longer than the portion of the aerosol-generating article configured to protrude from the device when the aerosol-generating article is inserted into the aerosol-generating device.

[0262] The diameter of the device cavity may be from approximately 4 mm to approximately 10 mm. The diameter of the device cavity may be from approximately 5 mm to approximately 9 mm. The diameter of the device cavity may be from approximately 6 mm to approximately 8 mm. The diameter of the device cavity may be from approximately 7 mm to approximately 8 mm. The diameter of the device cavity may be from approximately 7 mm to approximately 7.5 mm.

[0263] The diameter of the cavity of the device may be substantially the same as or larger than the diameter of the aerosol-generating article. The diameter of the cavity of the device may be the same as the diameter of the aerosol-generating article to form an interference fit with the aerosol-generating article.

[0264] The cavity of the device may be configured to form an interference fit with an aerosol-generating article received within the cavity of the device. The tight fit may refer to a sliding fit or an interference fit. The aerosol-generating device may comprise a peripheral wall. Such a peripheral wall may define the cavity of the device or a heating chamber. The peripheral wall defining the cavity of the device may be configured to engage the aerosol-generating article received within the cavity of the device via an interference fit, such that there is substantially no gap or empty space between the peripheral wall defining the cavity of the device and the aerosol-generating article when it is received within the device.

[0265] Such an interference fit may create a hermetic fit or configuration between the cavity of the device and the aerosol-generating article contained therein.

[0266] With such a sealed configuration, there will be substantially no gap or empty space between the peripheral wall defining the cavity of the device and the aerosol generating article for air to flow therethrough.

[0267] An interference fit with the aerosol generating article may be created along the entire length of the cavity of the device or along a portion of the length of the cavity of the device.

[0268] An aerosol-generating device may comprise an airflow channel extending between an inlet opening of the channel and an outlet opening of the channel. The airflow channel may be configured to create fluid communication between the interior of the cavity of the device and the exterior of the aerosol-generating device. The airflow channel of the aerosol-generating device may be defined within the casing of the aerosol-generating device to provide fluid communication between the interior of the cavity of the device and the exterior of the aerosol-generating device. When the aerosol-generating article is housed within the cavity of the device, the airflow channel may be configured to provide airflow into the article to deliver the generated aerosol to the user, who takes a puff through the mouthpiece end of the article.

[0269] The airflow passage of the aerosol-generating device may be defined within the peripheral wall of the casing of the aerosol-generating device or by this peripheral wall. In other words, the airflow passage of the aerosol-generating device may be defined within the thickness of the peripheral wall, by the inner surface of the peripheral wall, or by a combination of both. The airflow passage may be partially defined by the inner surface of the peripheral wall or may be partially defined within the thickness of the peripheral wall. The inner surface of the peripheral wall defines the peripheral boundary of the cavity of the device.

[0270] The air flow path of the aerosol-generating device may extend from an inlet located at the mouthpiece end or proximal end of the aerosol-generating device to an outlet located away from the mouthpiece end of the device. The air flow path may extend along a direction parallel to the longitudinal axis of the aerosol-generating device.

[0271] The heater may be any suitable type. Preferably, in the present invention, the heater is an external heater.

[0272] Preferably, the heater can externally heat the aerosol-generating article when it is placed within the aerosol-generating device. Such an external heater can surround the aerosol-generating article when it is inserted into or placed within the aerosol-generating device.

[0273] The heater may be configured to heat the outer surface of the aerosol-generating substrate. The heater may be positioned so as to be inserted into the aerosol-generating substrate when the aerosol-generating substrate is positioned within the cavity. The heater may be positioned within the cavity of the device, or a heating chamber.

[0274] The heater may comprise at least one heating element. The at least one heating element may be a heating element of any suitable type. The device may comprise only one heating element. The device may comprise a plurality of heating elements. The heater may comprise at least one resistive heating element. Preferably, the heater comprises multiple resistive heating elements. Preferably, the resistive heating elements are electrically connected in a parallel arrangement. Advantageously

[0275] Providing multiple resistive heating elements electrically connected in parallel can facilitate the delivery of the desired power to the heater while reducing or minimizing the voltage required to provide the desired power. Advantageously, reducing or minimizing the voltage required to operate the heater can contribute to reducing or minimizing the physical size of the power supply.

[0276] Suitable materials for forming at least one resistive heating element include, but are not limited to: semiconductors such as doped ceramics, electrically conductive ceramics (such as, for example, molybdenum disilicide), carbon, graphite, metals, metal alloys, and composite materials made from a ceramic material and a metallic material. Such composite materials may comprise doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbides. Examples of suitable metals include titanium, zirconium, tantalum, and platinum group metals.Examples of suitable metal alloys include stainless steel, nickel-, cobalt-, chromium-, aluminum-, titanium-, zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese-, and iron-based alloys, as well as nickel-, iron-, cobalt-, stainless steel-, Timetal®-, and iron-manganese-aluminum-based superalloys.

[0277] At least one resistive heating element may comprise one or more stamped parts made of an electrically resistive material, such as stainless steel. At least one resistive heating element may comprise a heating wire or filament, such as a wire made of Ni-Cr (nickel-chromium), platinum, tungsten, or an alloy.

[0278] At least one heating element may comprise an electrically insulating substrate, wherein at least one resistive heating element is provided on the electrically insulating substrate.

[0279] The electrically insulating substrate may comprise any suitable material. For example, the electrically insulating substrate may comprise one or more of paper, glass, ceramic, anodized metal, coated metal, and polyimide. Ceramics may include mica, aluminum oxide (Al2O3), or zirconium dioxide (ZrO2). Preferably, the electrically insulating substrate has a thermal conductivity of less than or equal to approximately 40 watts per meter Kelvin, preferably less than or equal to approximately 20 watts per meter Kelvin, and ideally less than or equal to approximately 2 watts per meter Kelvin.

[0280] The heater may comprise a heating element comprising a rigid, electrically insulating substrate with one or more electrically conductive tracks or wires located on its surface. The size and shape of the electrically insulating substrate may allow it to be inserted directly into the aerosol-generating substrate. If the electrically insulating substrate is not sufficiently rigid, the heating element may comprise additional amplifying means. Current may flow through the one or more electrically conductive tracks to heat the heating element and the aerosol-generating substrate.

[0281] The heater may comprise an induction heating device. The induction heating device may comprise an induction coil and a power supply configured to supply a high-frequency oscillating current to the induction coil. In the context of this document, "high-frequency oscillating current" means an oscillating current with a frequency of approximately 500 kHz to approximately 30 MHz. The heater may advantageously comprise a DC-to-AC converter for converting the DC current supplied by the DC power supply into an AC current. The induction coil may be designed to generate a high-frequency oscillating electromagnetic field upon receiving the high-frequency oscillating current from the power supply. The induction coil may be designed to generate a high-frequency oscillating electromagnetic field in the cavity of the device.The induction coil may substantially surround the cavity of the device. The induction coil may extend at least partially along the length of the cavity of the device.

[0282] The heater may comprise an induction heating element. The induction heating element may be a current collector. As used herein, the term "current collector" refers to an element comprising a material capable of converting electromagnetic energy into heat. When the current collector is placed in an alternating electromagnetic field, the current collector heats up. Heating of the current collector may result from at least one of hysteresis losses and eddy currents induced in the current collector, depending on the electrical and magnetic properties of the current collector material.

[0283] The current-receiving element can be configured such that, when the aerosol-generating article is accommodated in the cavity of the aerosol-generating device, the oscillating electromagnetic field generated by the induction coil induces a current in the current-receiving element, which leads to heating of the current-receiving element. The aerosol-generating device is preferably capable of generating a fluctuating electromagnetic field having a magnetic field strength (field strength H) of from 1 to 5 kiloamperes per meter (kA / m), preferably from 2 to 3 kA / m, for example, approximately 2.5 kA / m. The electrical aerosol-generating device is preferably capable of generating a fluctuating electromagnetic field having a frequency of from 1 to 30 MHz, for example, from 1 to 10 MHz, for example, from 5 to 7 MHz.

[0284] An aerosol-generating article may comprise a current-collecting element. The current-collecting element is preferably positioned in contact with an aerosol-generating substrate.

[0285] The current-collecting element can be located in an aerosol-generating device. The current-collecting element can be located in a cavity. The aerosol-generating device may contain only one current-collecting element. The aerosol-generating device may contain multiple current-collecting elements. The current-collecting element is preferably configured to heat the outer surface of the aerosol-generating substrate.

[0286] The current collector may comprise any suitable material. The current collector may be formed from any material that can be inductively heated to a temperature sufficient to release volatile compounds from the aerosol-generating substrate. Suitable materials for the elongated current collector include graphite, molybdenum, silicon carbide, stainless steels, niobium, aluminum, nickel, nickel compounds, titanium, and composites of metallic materials. Some current collectors comprise metal or carbon. Advantageously, the current collector may comprise or consist of a ferromagnetic material, such as ferritic iron, a ferromagnetic alloy such as ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrite. A suitable current collector may be made of or comprise aluminum.The current collecting element preferably contains more than about 5 percent, preferably more than about 20 percent, more preferably more than about 50 percent, or more than about 90 percent ferromagnetic or paramagnetic materials. Some elongated current collecting elements can be heated to a temperature in excess of about 250 degrees Celsius.

[0287] The current-collecting element may comprise a non-metallic core with a metallic layer located on the non-metallic core. For example, the current-collecting element may comprise metallic tracks formed on the outer surface of a ceramic core or substrate.

[0288] The aerosol generating device may comprise at least one resistive heating element and at least one inductive heating element. The aerosol generating device may comprise a combination of resistive heating elements and inductive heating elements.

[0289] During use, the heater can be controlled to operate within a specified operating temperature range below the maximum operating temperature. The preferred operating temperature range is from approximately 150 degrees Celsius to approximately 300 degrees Celsius in the heating chamber (or cavity of the device). The heater's operating temperature range can be from approximately 150 degrees Celsius to approximately 250 degrees Celsius.

[0290] Preferably, the operating temperature range of the heater may be from about 150 degrees Celsius to about 200 degrees Celsius. More preferably, the operating temperature range of the heater may be from about 180 degrees Celsius to about 200 degrees Celsius. In particular, it was found that optimal and stable aerosol delivery can be achieved by using an aerosol generating device having an external heater that has an operating temperature range of about 180 degrees Celsius to about 200 degrees Celsius, wherein the aerosol generating articles have a relatively low RTD (for example, the RTD of the downstream section is less than 15 mm H2O), as mentioned in the present disclosure.

[0291] In embodiments where the aerosol-generating article comprises a ventilation zone, the ventilation zone may be arranged so as to be open when the aerosol-generating article is contained within the cavity of the device. Thus, the length of the cavity of the device or the heating chamber may be less than the distance from the upstream end of the aerosol-generating article to the ventilation zone located along the downstream section. In other words, when the aerosol-generating article is contained within the aerosol-generating device, the distance between the ventilation zone and the upstream end of the upstream element may be greater than the length of the heating chamber.

[0292] When the article is placed inside the cavity of the device, the ventilation zone may be located at a distance of at least 0.5 mm (in the downstream direction relative to the article) from the mouthpiece end (or the surface of the mouthpiece end) of the cavity of the device or the device itself. When the article is placed inside the cavity of the device, the ventilation zone may be located at a distance of at least 1 mm (in the downstream direction relative to the article) from the mouthpiece end (or the surface of the mouthpiece end) of the cavity of the device or the device itself. When the article is placed inside the cavity of the device, the ventilation zone may be located at a distance of at least 2 mm (in the downstream direction relative to the article) from the mouthpiece end (or the surface of the mouthpiece end) of the cavity of the device or the device itself.

[0293] Preferably, the ratio between the distance between the ventilation zone and the upstream end of the upstream element and the length of the heating chamber is from about 1.03 to about 1.13.

[0294] This arrangement of the ventilation zone ensures that the ventilation zone is not blocked within the cavity of the device itself, while minimizing the risk of blocking by the user's lips or hands, since the ventilation zone is located as far upstream as possible relative to the end of the product located further downstream, without being blocked within the cavity of the device.

[0295] The aerosol-generating device may include a power supply. The power supply may be a DC power supply. The power supply may be a battery. The power supply may be a nickel-metal hydride battery, a nickel-cadmium battery, or a lithium-based battery, such as a lithium-cobalt, lithium-iron phosphate, or lithium-polymer battery. However, in some embodiments, the power supply may be another type of charge storage device, such as a capacitor. The power supply may require recharging and may have a capacity capable of storing sufficient energy for one or more user operations, such as one or more aerosol generation sessions.For example, the power supply may have sufficient capacity to continuously heat the aerosol-generating substrate for approximately six minutes, which corresponds to the typical time required to smoke a conventional cigarette, or for a period of time that is a multiple of six minutes. In another example, the power supply may have sufficient capacity to support a specified number of puffs or individual heater activations.

[0296] The following is a non-exhaustive list of non-limiting examples. Any one or more features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0297] EX1. An aerosol-generating article comprising a rod of aerosol-generating substrate; and a downstream section provided downstream of the rod of aerosol-generating substrate.

[0298] EX2. An aerosol generating article according to example EX1, wherein the downstream section comprises an air conducting member adjacent to the rod of the aerosol generating substrate, preferably adjacent to the downstream end of the rod of the aerosol generating substrate.

[0299] EX3. The aerosol generating article according to example EX2, wherein the air conduction member of the downstream section is a downstream air conduction member.

[0300] EX4. An aerosol-generating article according to any preceding example, further comprising an upstream section located upstream of the aerosol-generating substrate rod, wherein the upstream section comprises at least one upstream element.

[0301] EX5. An aerosol generating article according to example EX4, wherein at least one upstream element comprises an upstream air conducting element.

[0302] EX6. An aerosol-generating article according to example EX4 or EX5, wherein the upstream end of the upstream element defines the upstream end of the aerosol-generating article.

[0303] EX7. An aerosol-generating article according to example EX1, further comprising an upstream section located upstream of the aerosol-generating substrate rod and a downstream section located downstream of the aerosol-generating substrate rod, wherein the upstream section comprises an upstream air-conducting element adjacent to the upstream end of the aerosol-generating substrate rod, and the downstream section comprises a downstream air-conducting element adjacent to the downstream end of the aerosol-generating substrate rod.

[0304] EX8. An aerosol generating article according to any preceding example, wherein the air conducting member comprises at least one outer air passage, wherein the at least one outer air passage may define an inner air passage or an outer air passage.

[0305] EX9. An aerosol generating article according to any preceding example, wherein the air conducting member comprises a groove formed on an outer surface of the main portion of the air conducting member, wherein the groove defines an outer air passage extending from an upstream end of the air conducting member to a downstream end of the air conducting member.

[0306] EX10. An aerosol generating article according to any preceding example, wherein the main portion of the air conducting element comprises a core portion and a peripheral portion where at least one groove is formed, wherein the core portion is substantially solid.

[0307] EX11. An aerosol-generating article according to any preceding example, wherein the air-conducting member does not define an internal cavity.

[0308] EX12. An aerosol-generating article according to any preceding example, wherein the air-conducting element comprises a main portion comprising a core portion and a peripheral portion, wherein the core portion comprises one or more internal air passages, and the peripheral portion comprises one or more external air passages, wherein the total cross-sectional area of ​​the one or more external air passages is greater than the total cross-sectional area of ​​the one or more internal air passages.

[0309] EX13. An aerosol-generating article according to any preceding example, wherein the ratio of the total cross-sectional area of ​​the one or more outer air passages to the total cross-sectional area of ​​the one or more inner air passages is at least 2.

[0310] EX14. An aerosol-generating article according to any preceding example, wherein the ratio of the total cross-sectional area of ​​the one or more outer air passages to the total cross-sectional area of ​​the one or more inner air passages is at least 3.

[0311] EX15. An aerosol-generating article according to any preceding example, wherein the ratio of the total cross-sectional area of ​​one or more outer air passages to the total cross-sectional area of ​​one or more inner air passages is no more than 10.

[0312] EX16. An aerosol-generating article according to any preceding example, wherein the one or more outer air passages provide at least four outer air passages.

[0313] EX17. An aerosol-generating article according to any preceding example, wherein each external air passage is defined by a groove provided on the outer surface of the or each air passage element.

[0314] EX18. An aerosol-generating article according to any preceding example, wherein each external air passage is defined by an internal air cavity or channel extending along the or each air conduction element.

[0315] EX19. An aerosol generating article according to any preceding example, wherein the ratio of the total cross-sectional area of ​​the one or more outer air passages to the total cross-sectional area of ​​the air conducting element is at least approximately 30 percent.

[0316] EX20. An aerosol-generating article according to any preceding example, further comprising a mouthpiece element provided downstream of the aerosol-generating substrate rod, wherein the air-conducting element is located upstream of the aerosol-generating substrate rod or between the aerosol-generating substrate rod and the mouthpiece element.

[0317] EX21. An aerosol-generating article according to any preceding example, further comprising a mouthpiece element provided downstream of the aerosol-generating substrate rod, wherein the upstream air-conducting element is positioned upstream of the aerosol-generating substrate rod, or the downstream air-conducting element is positioned between the aerosol-generating substrate rod and the mouthpiece element.

[0318] EX22. An aerosol-generating article according to any preceding example, further comprising a hollow tubular member provided downstream of the aerosol-generating substrate rod, wherein the air-conducting member is located upstream of the aerosol-generating substrate rod or between the aerosol-generating substrate rod and the hollow tubular member.

[0319] EX23. An aerosol-generating article according to any preceding example, further comprising a hollow tubular member provided downstream of the aerosol-generating substrate rod, wherein the upstream air-conducting member is positioned upstream of the aerosol-generating substrate rod, or the downstream air-conducting member is positioned between the aerosol-generating substrate rod and the hollow tubular member.

[0320] EX24. An aerosol-generating article according to any preceding example, wherein the or each air-conducting element is substantially air-impermeable.

[0321] EX25. An aerosol-generating article according to any preceding example, wherein the or each air-conducting element is formed by thermoforming.

[0322] EX26. An aerosol-generating article according to any preceding example, wherein the groove depth is at least 0.5 mm.

[0323] EX27. An aerosol-generating article according to any preceding example, wherein the groove depth is not more than 2 mm.

[0324] EX28. An aerosol generating article according to any preceding example, wherein the or each air conducting element comprises at least four grooves.

[0325] EX29. An aerosol-generating article according to any preceding example, wherein the groove extends along a spiral path or a wave-shaped path.

[0326] EX30. An aerosol-generating article according to any preceding example, further comprising a wrapper surrounding the or each air-conducting element, wherein the wrapper covers the outer air passage defined by the groove such that the wrapper defines the boundary of the outer air passage.

[0327] EX31. An aerosol-generating article according to any preceding example, further comprising a ventilation zone.

[0328] EX32. An aerosol generating article according to example EX31, wherein the ventilation zone is provided at a location along the hollow tubular element of the downstream section.

[0329] EX33. An aerosol-generating article according to any preceding example, wherein the rod of the aerosol-generating substrate has a length of between 8 millimeters and 16 millimeters.

[0330] EX34. An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate rod has a resistance to draw (RTD) of between 4 mmH2O and 10 mmH2O.

[0331] EX35. An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises shredded tobacco material.

[0332] EX36. An aerosol-generating article according to example EX35, wherein the shredded tobacco material has an average density of from 150 milligrams per cubic centimeter to 500 milligrams per cubic centimeter.

[0333] EX37. An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises one or more aerosol-forming substances, and wherein the content of the aerosol-forming substance in the aerosol-generating substrate is from 10 percent to 20 percent by weight, calculated on a dry weight basis.

[0334] EX38. An aerosol-generating article according to example EX37, wherein the aerosol-forming substance comprises one or more of glycerin and propylene glycol.

[0335] EX39. An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises cut tobacco filler.

[0336] EX40. An aerosol-generating article according to any preceding example, wherein the outer diameter of the article is substantially uniform along its length.

[0337] EX41. An aerosol generating system comprising an aerosol generating article according to any of the previous examples, and an aerosol generating device comprising a heating chamber for containing the aerosol generating article, and at least a heating element provided on or along the periphery of the heating chamber.

[0338] The present invention will now be further described with reference to the accompanying drawings, in which:

[0339] Fig. 1a is a schematic exploded side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0340] Fig. 1b is a schematic side perspective view of the assembled aerosol generating article as shown in Fig. 1a;

[0341] Fig. 2 is a schematic side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0342] Fig. 3 is a schematic side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0343] Fig. 4 is a schematic side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0344] Fig. 5a is a cross-sectional view of an air conducting member of an aerosol generating article according to an embodiment of the present invention;

[0345] Fig. 5b is a cross-sectional view of an air conducting member of an aerosol generating article according to an embodiment of the present invention;

[0346] Fig. 6a is a schematic exploded side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0347] Fig. 6b is a schematic exploded side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0348] Fig. 6c is a schematic exploded side perspective view of an aerosol generating article according to an embodiment of the present invention;

[0349] Fig. 7 is a cross-sectional view of an air conducting member of an aerosol generating article according to an embodiment of the present invention;

[0350] Fig. 8a is a side cross-sectional view of an aerosol generating system according to the present disclosure;

[0351] Fig. 8b shows a partial cross-sectional view of the air conducting element of the aerosol generating article along the line A-A shown in Fig. 8a; and

[0352] Fig. 8C is a partial cross-sectional view of the air conducting member of the aerosol generating article along the line A-A shown in Fig. 8a.

[0353] Figure 1a illustrates an aerosol-generating article 10 comprising a rod of aerosol-generating substrate 12 and a downstream section at a location downstream of the rod 12 of aerosol-generating substrate. The aerosol-generating article 10 extends from an upstream, or distal, end 16 to a downstream, or mouthpiece, end 18, which coincides with the downstream end of the downstream section. As shown in Figure 1a, the downstream section comprises a downstream air-conducting element 11 and a mouthpiece element 8.

[0354] The aerosol-generating article 10 has an overall length of approximately 45 millimeters and an outer diameter of approximately 7.2 mm. The length of the aerosol-generating substrate 12 is approximately 8 mm.

[0355] The aerosol-generating substrate rod 12 contains shredded tobacco material. The aerosol-generating substrate rod 12 contains 150 milligrams of shredded tobacco material containing 13 percent by weight to 16 percent by weight of glycerin. The density of the aerosol-generating substrate is approximately 300 mg per cubic centimeter. The RTD of the aerosol-generating substrate rod 12 is approximately 6-8 mm H2O. The aerosol-generating substrate rod 12 is individually wrapped in a filament (not shown).

[0356] The downstream air conducting element 11 is positioned immediately downstream of the aerosol generating substrate rod 12, wherein the downstream air conducting element 11 is in longitudinal alignment with the rod 12. The upstream end of the downstream air conducting element 11 is adjacent to the downstream end of the aerosol generating substrate rod 12.

[0357] The outer air passages for moving air and aerosol through them are represented by grooves 5 provided around the outer surface of the air conduction element 11. The air conduction element 11 comprises six grooves 5 extending longitudinally along the main part of the air conduction element 11.

[0358] The air conducting element 11 also comprises an internal air passage 7 extending along and through the center of the main part of the air conducting element 11.

[0359] The length of the downstream air conducting element 11 is approximately 12 mm.

[0360] The mouthpiece element 8 extends from the downstream end of the air conducting element 11 to the downstream, or mouthpiece, end of the aerosol generating article 10. The mouthpiece element 8 has a length of approximately 7 mm. The outer diameter of the mouthpiece element 8 is approximately 7.2 mm. The mouthpiece element 8 comprises a filter segment made of low-density cellulose acetate. The RTD of the mouthpiece element 8 is approximately 8 mm H2O. The mouthpiece element 8 can be individually wrapped with a filament (not shown).

[0361] Fig. 1b illustrates an aerosol generating article 10 collected in a wrapper 52 surrounding the components of the article 10. External air passages are formed between the grooves 5 and the inner surface of the wrapper 52.

[0362] Figure 2 illustrates an aerosol-generating article 10a similar to the aerosol-generating article 10, but comprising a ventilation zone 13 provided at a location along the air-conducting element 11. In more detail, the ventilation zone 13 is provided at a distance of approximately 16 millimeters from the downstream end 18 of the article 10. The ventilation zone 13 comprises an annular row of openings or perforations surrounding the air-conducting element 11. The perforations of the ventilation zone 13 allow fluid to enter the grooves 5 from the outside of the article 10. Any other embodiments described herein may also have a ventilation zone that provides fluid communication between the outside of the article 10 and any external air passages (including grooves) defined in the air-conducting element.

[0363] Figure 3 illustrates an aerosol generating article 20 similar to the aerosol generating article 10, but comprising a hollow tubular member 14 instead of the downstream air conducting member 11, and an upstream section located upstream of the aerosol generating substrate rod 12, comprising an upstream air conducting member 15. Like the downstream air conducting member 11, the upstream air conducting member 15 (or the upstream or front plug) comprises outer air passages in the form of grooves 5 for moving air therein, provided around the outer surface of the air conducting member 15. The air conducting member 15 also comprises six grooves 5 extending longitudinally along the main portion of the air conducting member 15.A hollow tubular element 14 is provided between the rod of the aerosol-generating substrate 12 and the mouthpiece element 8. An upstream air-conducting element 15 has a length of approximately 5 mm. The hollow tubular element 14 may have a length of approximately 10 mm.

[0364] Figure 4 illustrates an aerosol generating article 30 similar to the aerosol generating article 10, but further comprising an upstream section located upstream of the aerosol generating substrate rod 12, comprising an upstream air conducting element 15 as described above.

[0365] Fig. 5a and Fig. 5b show cross-sections of embodiments of the air conduction elements 11, 15. As shown in Fig. 5a and Fig. 5b, the air conduction elements 11, 15 comprise an internal air passage 7 passing through the core portion C of the main portion of the air conduction elements 11, 15, in addition to four grooves 5 defined on the peripheral portion P of the main portion of the air conduction elements 11, 15. The grooves 5 have a depth H of approximately 1.5 mm. The main portion of the air conduction elements 11, 15 has an outer diameter D of approximately 7.2 mm. The internal air passage 7 has a circular cross-section and a diameter of approximately 1 mm.

[0366] Fig. 6a, Fig. 6b and Fig. 6c respectively illustrate embodiments similar to those shown in Fig. 1a, Fig. 3 and Fig. 4. The aerosol generating articles 61, 62 and 63 respectively shown in Fig. 6a, Fig. 6b and Fig. 6c are characterized in that the outer air passages of the downstream or upstream air conducting elements 11, 15 are defined not by grooves 5, but by inner, outer air passages 51 extending along and through the main part of the air conducting elements 11, 15. The inner, outer air passages 51 are defined around the inner air passage 7. As shown in Fig. 7, while the internal air passage 7 is defined in the core portion C of the main portion of the air conducting elements 11, 15, the external air passages 51 are defined in the peripheral portion P of the main portion of the air conducting elements 11, 15.The air-conducting elements 11, 15 shown in Fig. 6a, Fig. 6b and Fig. 6c comprise four outer air passages 51 formed within the material of the air-conducting elements 11, 15, and not on the outer surface like the grooves 5. Accordingly, the total cross-sectional area of ​​the outer air passages 51 is larger than the total cross-sectional area of ​​the inner air passage 7. For example, the diameters of the inner air passage 7 and the outer air passages 51 are approximately 1.5 mm.

[0367] Figure 8a shows an aerosol generating system 1 comprising an exemplary aerosol generating device 100 (for ease of reference, only a portion thereof is shown) and an aerosol generating article 10 according to the embodiments shown in Figure 1a, Figure 1b and Figure 6a. Any embodiment of an aerosol generating article according to the present disclosure can be used in the system 1.

[0368] Fig. 8a illustrates a downstream portion in the form of a mouthpiece end of an aerosol generating device 100, where a cavity of the device or a heating chamber is defined, and an aerosol generating article 10 can be accommodated. The aerosol generating device 1 comprises a housing 24 extending between the mouthpiece end and a distal end (not shown). The housing 24 comprises a peripheral wall 26. The peripheral wall 26 defines a cavity of the device for accommodating the aerosol generating article 10. The cavity of the device is defined by a closed distal end and an open mouthpiece end. The mouthpiece end of the cavity of the device is located on the mouthpiece end of the aerosol generating device 1. The aerosol generating article 10 is configured to be received through the mouthpiece end of the cavity (or heating chamber) of the device and is configured to be adjacent to the distant closed end of the cavity of the device.

[0369] The air flow inlet 22 of the device is defined at the distal end of the cavity of the device. Air can enter the aerosol-generating substrate 12 through the air flow inlet 22, providing fluid communication between the outer portion of the device 1 and the rod of the aerosol-generating substrate 12.

[0370] The aerosol generating device 1 further comprises an external heater 28 and a power source (not shown) for supplying power to the heater 28. A controller (not shown) is also provided for controlling such power supply to the heater 28. The heater 28 is configured to controllably heat the aerosol generating article 10 during use when the aerosol generating article 10 is housed inside the device 1. The heater 28 has the form of a heating tube and is configured to externally heat the aerosol generating substrate 12.

[0371] Fig. 8b and Fig. 8c show how the aerosol is drawn from the peripheral portion of the PS rod of the aerosol-generating substrate 12 during the initial stages of heating. As shown in Fig. 8b, when the aerosol-generating substrate 12 is heated, the aerosol is primarily drawn from the peripheral portion of the PS of the substrate 12. The long dash-dotted line B denotes the imaginary boundary between the peripheral portion of the PS of the substrate 12 and the core portion of the CS of the substrate 12, the heating of which and the generation of the aerosol after the start of the heating cycle may take longer. The downstream air-conducting element 11 advantageously facilitates the drawing of aerosol from the peripheral portion of the PS substrate 12 through the outer air passages defined by the grooves 5, thereby accelerating the generation and delivery of the consumable aerosol to the user located downstream. As shown in Fig. 8b and Fig.8 s, the aerosol from the core portion of the CS substrate 12 can be drawn in through the internal air passage 7.

[0372] For the purposes of the present description and the appended claims, except where otherwise indicated, all numbers expressing quantities, amounts, percentages, etc., are to be understood as modified in all instances by the term "about." Also, all ranges include the disclosed maximum and minimum points and include any intermediate ranges therebetween, which may or may not be specifically listed herein. Therefore, in this context, the number A is understood as A±10% of A. In this context, the number A can be considered as including numerical values ​​that are within the normal standard error for measuring the property that the number A modifies. The number A, in some cases, when used in the appended claims, may deviate by the percentages listed above, provided that the amount by which A deviates does not materially affect the basic and novel characteristic(s) of the claimed invention.All ranges also include the disclosed high and low points and include any intermediate ranges therebetween that may or may not be specifically listed herein.

Claims

1. An aerosol generating system comprising an aerosol generating article for producing an inhalable aerosol upon heating and an aerosol generating device comprising a heating chamber, wherein the aerosol generating article is configured to be placed in the heating chamber and comprises: aerosol generating substrate rod; a downstream section located downstream of the aerosol-generating substrate rod, wherein the downstream section comprises a downstream air-conducting element adjacent to the downstream end of the aerosol-generating substrate rod, wherein the downstream air-conducting element comprises a main portion comprising a core portion and a peripheral portion surrounding the core portion, wherein the peripheral portion extends between an outer periphery of the air-conducting element and the core portion, wherein the core portion comprises one or more internal air passages and the peripheral portion comprises one or more external air passages, wherein the total cross-sectional area of ​​the one or more external air passages is greater thanthan the total cross-sectional area of ​​one or more internal air passages; and, a ventilation zone located along a downstream air passage element, wherein the ventilation zone creates fluid communication with one or more external air passages; wherein the aerosol generating device comprises a heater configured to externally heat the aerosol generating substrate rod.

2. An aerosol generating system according to claim 1, characterized in that the aerosol generating article further comprises an upstream section located upstream of the aerosol generating substrate rod, wherein the upstream section comprises an upstream air conducting element adjacent to the upstream end of the aerosol generating substrate rod, wherein the upstream air conducting element comprises a main portion comprising a core portion and a peripheral portion, wherein the core portion comprises one or more internal air passages and the peripheral portion comprises one or more external air passages, wherein the total cross-sectional area of ​​the one or more external air passages is greater than the total cross-sectional area of ​​the one or more internal air passages.

3. An aerosol generating system according to any one of the preceding claims, characterized in that the downstream section further comprises a mouthpiece element, wherein the downstream air conducting element is positioned between the aerosol generating substrate rod and the mouthpiece element.

4. An aerosol generating system according to any one of the preceding claims, characterized in that the downstream section further comprises a hollow tubular element, wherein the downstream air conducting element is positioned between the aerosol generating substrate rod and the hollow tubular element.

5. An aerosol generating system according to any one of the preceding claims, characterized in that each outer air passage is defined by a groove provided on the outer surface of the air conduction element.

6. An aerosol generating system according to claim 5, characterized in that the groove depth is at least 0.5 mm.

7. An aerosol generating system according to any one of paragraphs 5-6, characterized in that the depth of the groove is no more than 2 mm.

8. An aerosol generating system according to any one of paragraphs 1-4, characterized in that each external air passage is defined by an internal cavity extending along the air conduction element.

9. An aerosol generating system according to any one of the preceding claims, characterized in that the ratio of the total cross-sectional area of ​​one or more outer air passages to the total cross-sectional area of ​​one or more inner air passages is at least 2.

10. An aerosol generating system according to any one of the preceding claims, characterized in that the ratio of the total cross-sectional area of ​​one or more outer air passages to the total cross-sectional area of ​​one or more inner air passages is no more than 10.

11. An aerosol generating system according to any one of the preceding claims, wherein the one or more external air passages provide at least four external air passages.

12. An aerosol generating system according to any one of the preceding claims, characterized in that the ratio of the total cross-sectional area of ​​the one or more outer air passages to the total cross-sectional area of ​​the air conducting element is at least approximately 30%.

13. An aerosol generating system according to any one of the preceding claims, characterized in that the aerosol generating substrate has an aerosol forming substance content of at least 5% on a dry weight basis.

14. An aerosol generating system according to any one of the preceding claims, characterized in that the aerosol generating substrate has an aerosol forming substance content of at least 10% on a dry weight basis.

Images