Hollow tubular element for aerosol generating article

Abstract

A hollow tubular element (100) for an aerosol-generating article (1), the hollow tubular element (100) comprising a peripheral portion (110) providing a curved outer surface of the hollow tubular element (100) and defining a hollow interior region (120) of the hollow tubular element (100), and an internal protrusion (130) extending into the hollow interior region (120). The hollow tubular element (100) is formed from a sheet, the sheet comprising a first portion and a second portion adjacent to the first portion, with a first fold (141) therebetween. The first portion of the sheet forms at least a portion of the peripheral portion (110) of the hollow tubular element (100). The entire first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element (100). The second portion of the sheet defines an internal projection (130) of the hollow tubular element (100), the internal projection (130) extending from the first fold (131) into the hollow interior region (120) of the hollow tubular element (100).

Description

Technical Field

[0001] The present invention relates to a hollow tubular element for an aerosol-generating article, which comprises an aerosol-forming substrate and is adapted to generate inhalable aerosol upon heating. Background Art

[0002] Aerosol-generating articles in which an aerosol-forming substrate, such as a tobacco-containing substrate, is heated rather than combusted are known in the art.

[0003] A conventional cigarette is ignited when a user applies a flame to one end of the cigarette and draws air through the other end. The localized heat provided by the flame and the oxygen in the air drawn through the cigarette ignites the end of the cigarette, and the resulting combustion generates inhalable smoke. In contrast, in heated aerosol-generating articles, aerosol is typically generated by transferring heat from a heat source to a physically separate aerosol-forming substrate or material, and this aerosol-forming substrate or material may be located in contact with the heat source, within the heat source, around the heat source, or downstream of the heat source. During use of the aerosol-generating article, volatile compounds are released from the aerosol-forming substrate by heat transfer from the heat source and are entrained in the air drawn through the aerosol-generating article. As the released compounds cool, they condense to form an aerosol.

[0004] Numerous prior art documents disclose aerosol generators for consuming aerosol-generating articles. Such devices include, for example, electrically heated aerosol generators in which aerosols are generated by heat transfer from an electric heater element of the aerosol generator to an aerosol-generating substrate of a heated aerosol-generating article. For example, electrically heated aerosol generators have been proposed that include internal heater blades adapted to be inserted into an aerosol-forming substrate. Alternatively, an inductively exothermic aerosol-generating article comprising an aerosol-generating substrate and a susceptor element disposed within the aerosol-generating substrate has been proposed by WO2015 / 176898.

[0005] Aerosol-generating articles in which the tobacco-containing substrate is heated rather than burned present numerous challenges not seen in conventional smoking articles. For example, it may be desirable to restrict the movement of the aerosol-generating substrate within the aerosol-generating article while ensuring that a sufficient level of airflow can pass through the aerosol-generating substrate and the aerosol-generating article. Restricting the potential movement of the aerosol-generating substrate is particularly desirable because it may help improve the consistency of performance between aerosol-generating articles by helping to increase the consistency of the interaction between the aerosol-generating substrate and the heater element. This may be particularly relevant to aerosol-generating articles adapted to receive heater blades, as the act of inserting heater blades may otherwise increase the possibility of displacement of the aerosol-generating substrate.

[0006] WO2013 / 098405 proposes including a hollow tubular element immediately downstream of the aerosol-forming substrate. The hollow tubular element is provided in the form of an annular hollow cellulose acetate tube. The hollow cellulose acetate tube is configured to resist the downstream movement of the aerosol-forming substrate during the insertion of the heating element of the aerosol generator into the aerosol-forming substrate. The empty space within the hollow cellulose acetate tube provides an opening for the aerosol to flow from the aerosol-forming substrate toward the mouth end of the aerosol-generating article.

[0007] However, these hollow tubular elements may have one or more drawbacks, such as inconsistent performance, limitations in materials and / or design, manufacturing challenges, and undesirable RTD properties. [Overview of the project] [Problems that the invention aims to solve]

[0008] Therefore, it is desirable to provide a novel and improved hollow tubular element for aerosol-generating articles that is less likely to have one or more of these drawbacks. [Means for solving the problem]

[0009] This disclosure relates to a hollow tubular element for an aerosol-generating article. The aerosol-generating article may comprise a first element, which may include an aerosol-forming substrate. The aerosol-generating article may comprise a hollow tubular element, which may be located downstream of the first element. The hollow tubular element may include a peripheral portion, which may provide a curved outer surface of the hollow tubular element. The peripheral portion may define the hollow inner region of the hollow tubular element. The hollow tubular element may include an internal projection, which may extend into the hollow inner region. The hollow tubular element may be formed from a sheet, which may include a first portion, which may include a second portion, which may be adjacent to the first portion of the sheet, with a first fold between them. A first portion of the sheet may form at least a portion of the peripheral portion of the hollow tubular element. The entire first portion of the sheet may form at least a portion of the curved outer surface of the hollow tubular element. A second portion of the sheet may define an internal projection of the hollow tubular element. The internal projection may extend from the first fold into the hollow inner region of the hollow tubular element.

[0010] The present invention provides a hollow tubular element. The hollow tubular element includes a peripheral portion. The peripheral portion of the hollow tubular element provides a curved outer surface of the hollow tubular element. The peripheral portion of the hollow tubular element defines the hollow inner region of the hollow tubular element. The hollow tubular element includes an internal projection. The internal projection extends into the hollow inner region. The hollow tubular element is formed from a sheet. The sheet includes a first portion. The sheet includes a second portion. The second portion of the sheet is adjacent to the first portion of the sheet. The second portion of the sheet is adjacent to the first portion of the sheet with a first fold in between. The first portion of the sheet forms at least a portion of the peripheral portion of the hollow tubular element. The entire first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element. The second portion of the sheet defines the internal projection of the hollow tubular element. The internal protrusion extends from the first fold into the hollow inner region of the hollow tubular element.

[0011] Internal projections of a hollow tubular element can form support elements for the hollow tubular element. Therefore, as used herein, internal projections of a hollow tubular element may also be referred to as support elements for the hollow tubular element.

[0012] The hollow tubular element of the present invention is formed from a sheet and has a support element that is subordinate to a first portion of the sheet along a first fold of the sheet and extends into the hollow inner region of the hollow tubular element. In an aerosol generating article containing a hollow tubular element, the support element may act to provide a support barrier to at least a portion of the first element of the aerosol generating article. In particular, the support element may act to provide a support barrier for at least a portion of the aerosol forming substrate of the first element. This can reduce the availability of empty space for pushing material from the aerosol forming substrate, for example, when the aerosol generating article interacts with an aerosol generating device or when the aerosol generating article is handled or transported. The interaction may include inserting the aerosol generating article into an aerosol generating device. In other words, the support element may provide a support barrier that prevents or limits the downstream movement of at least a portion of the aerosol forming substrate, for example. As a result, in the aerosol-generating article comprising the hollow tubular element of the present invention, the likelihood of a portion of the aerosol-forming material being extruded from the aerosol-forming substrate while the aerosol-generating article is in use may be reduced. This can lead to a more consistent user experience.

[0013] Furthermore, since the hollow tubular element is formed from the sheet and the support element is dependent on the first portion of the sheet along the first fold of the sheet, the first portion of the sheet forms at least a portion of the peripheral portion of the hollow tubular element, and the entire first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element, the hollow tubular element can still maintain an opening of appropriate size so that the aerosol flows from the aerosol-forming substrate toward the mouth end of the aerosol-generating article. This means that the hollow tubular element can still have a sufficiently low draw resistance. This also means that the hollow tubular element can still have a sufficiently low filtration effect.

[0014] Furthermore, by arranging the support element along a first fold of the sheet so as to be dependent on the first portion of the sheet, such that the first portion of the sheet forms at least a portion of the peripheral portion of the hollow tubular element, and the entire first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element, the present invention can provide a simple and straightforward method for forming a hollow tubular element with a support element. This makes it possible to reduce the amount of material used in constructing the hollow tubular element. This makes it possible to employ a simpler design for the hollow tubular element.

[0015] Furthermore, forming hollow tubular elements from a sheet can provide flexibility in the design of hollow tubular elements. In particular, forming hollow tubular elements from a sheet can provide flexibility in the design of support elements, and when the support elements provide their support barriers. This is because the flexibility of the sheet can easily be formed into a shape that is optimal for providing a support barrier to, for example, a first element and any components provided therein. This advantage may be particularly beneficial for aerosol generating articles having susceptor elements that can be located at several positions within the first element. Thus, the flexibility in the design of support elements, and when the support elements provide their support barriers, may mean that the support elements can be designed to effectively support the first element and any components provided therein.

[0016] Furthermore, compared to conventional hollow acetate tubes, the hollow inner region of the hollow tubular element of the present invention may have a proportionally larger cross-sectional area. This can advantageously increase the porosity of the hollow tubular element. This can advantageously lead to a deceleration of the aerosol as it passes through the hollow tubular element. This may mean that the aerosol spends more time in the hollow inner region of the hollow tubular element, and therefore, greater cooling of the aerosol may be possible.

[0017] Furthermore, compared to conventional hollow acetate tubes, the hollow tubular elements of the present invention may require less material, resulting in a lighter hollow tubular element overall. Moreover, compared to conventional hollow acetate tubes, the hollow tubular elements of the present invention may be made from more biodegradable materials, such as certain forms of paper.

[0018] Furthermore, compared to conventional hollow acetate tubes, the hollow tubular elements of the present invention may exhibit lower draw resistance when placed in an aerosol-generating article, particularly when placed immediately downstream of the first element.

[0019] In this specification, the term "aerosol-generating article" means an article in which an aerosol-forming substrate is heated to generate an inhalable aerosol and deliver it to a consumer.

[0020] As used herein, the term "aerosol-forming substrate" means a substrate that has the ability to release compounds and generate aerosols upon heating.

[0021] As used herein, the term “hollow tubular element” is used to mean a generally elongated element that defines a lumen or airflow passage along its longitudinal axis. In particular, the term “tubular” is used below with respect to a tubular body having a substantially cylindrical cross-section and a tubular element that defines at least one airflow conduit establishing an uninterrupted fluid communication between the upstream and downstream ends of the tubular body. However, naturally, alternative shapes of tubular bodies (e.g., alternative cross-sectional shapes) may be possible.

[0022] As used herein, the term “longitudinal direction” refers to the direction corresponding to the main longitudinal axis of the aerosol-generating article, extending between the upstream and downstream ends of the article.

[0023] As used herein, the term "transverse direction" refers to a direction perpendicular to the longitudinal axis of an aerosol-generating article. Any reference to a "cross-section" of an aerosol-generating article or a component thereof refers to a transverse cross-section, unless stated otherwise.

[0024] As used herein, the terms "upstream" and "downstream" describe the relative position of elements (or portions of elements) of the aerosol-generating article with respect to the direction in which the aerosol is conveyed through the aerosol-generating article during use.

[0025] As used herein, the term "sheet" means a laminar element having a width and a length substantially greater than its thickness.

[0026] The second portion of the sheet is adjacent to the first portion of the sheet with a first fold therebetween. This means that only the first fold is provided between the first portion of the sheet and the second portion of the sheet. In other words, no other portion of the sheet is interposed between the first portion of the sheet and the second portion of the sheet. The second portion of the sheet is dependent on the first portion of the sheet along the first fold.

[0027] The first portion of the sheet forms at least a part of the peripheral portion of the hollow tubular element. Accordingly, at least a part of the peripheral portion and the support element are integrally formed from the sheet. In other words, at least a part of the peripheral portion and the support element may be formed from the same sheet. The entire peripheral portion and the support element may be integrally formed from the sheet. For example, the first portion of the sheet may define the entire outer surface of the peripheral portion. The second portion of the sheet is dependent on the peripheral portion of the hollow tubular element along the first fold of the sheet. Thus, the support element of the hollow tubular element is dependent on the peripheral portion of the hollow tubular element along the first fold of the sheet.

[0028] The peripheral portion may have a generally tubular shape.

[0029] The entirety of the first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element. The entirety of the first portion of the sheet may form substantially the entire curved outer surface of the hollow tubular element.

[0030] The support element may extend along a portion of the length of the hollow tubular element. Preferably, the support element extends from the upstream end of the hollow tubular element. This means that the support element may be located at the end of the hollow tubular element closest to the first element of the aerosol-generating article. Thus, the support element may be able to better prevent or restrict the movement of the first element and any components provided inside it. Preferably, the support element extends to the downstream end of the hollow tubular element. The support element may extend along about 10 percent or more of the length of the hollow tubular element, preferably about 40 percent or more, and more preferably about 80 percent or more. Most preferably, the support element extends along substantially the entire length of the hollow tubular element. Thus, the support element may have a length approximately equal to the length of the hollow tubular element. This may provide a hollow tubular element with additional mechanical strength and rigidity along its entire length.

[0031] The support element may have a length of about 4 mm or more, preferably about 6 mm or more, more preferably about 8 mm or more, or about 15 mm or more.

[0032] The support element may have a length of about 40 mm or less, preferably about 30 mm or less, and more preferably about 20 mm or less.

[0033] The support element may have a length of about 4 mm to about 40 mm, preferably about 6 mm to about 30 mm, more preferably about 8 mm to about 20 mm, or 15 mm to about 20 mm.

[0034] The support element may have a length of approximately 8 millimeters. The support element may have a length of approximately 18 millimeters.

[0035] The support element is subordinate to the peripheral portion along the first fold of the sheet. Advantageously, this simplifies the manufacture of the hollow tubular element and can provide a suitable support barrier for the first element of the aerosol-generating article, and any components provided therein.

[0036] A first portion of the sheet forming at least a part of the peripheral portion of the hollow tubular element can be attached to the rest of the peripheral portion with adhesive. The use of adhesive may help improve the mechanical strength of the hollow tubular element in one or both of the longitudinal and transverse directions. Thus, this may help improve the ability of the hollow tubular element to provide a support barrier and its resistance to collapse or deformation. The first portion of the sheet may form the entire peripheral portion of the hollow tubular element.

[0037] The first fold may extend along a portion of the length of the hollow tubular element. In this case, the support element also extends along a portion of the length of the hollow tubular element. Preferably, the first fold extends from the upstream end of the hollow tubular element. Preferably, the first fold extends to the downstream end of the hollow tubular element. The first fold may extend along about 10 percent or more of the length of the hollow tubular element, preferably about 40 percent or more, and more preferably about 80 percent or more. Most preferably, the first fold extends along substantially the entire length of the hollow tubular element.

[0038] The first fold may be parallel to the longitudinal axis of the hollow tubular element. The first fold may be non-parallel to the longitudinal axis of the hollow tubular element. The first fold may be designed to be non-parallel to the longitudinal axis of the hollow tubular element so that the internal protrusion induces a swirling airflow pattern within the cavity of the hollow tubular element.

[0039] If the sheet includes a fold, the sheet may be deflected by an angle greater than approximately 45 degrees, greater than approximately 60 degrees, greater than approximately 75 degrees, or greater than approximately 90 degrees around the fold.

[0040] The folds may be crease lines. The sheet may include score lines aligned with the folds to assist in folding the sheet.

[0041] As used herein, the term “length” means the dimensions of the components of an aerosol-generating article in the longitudinal direction. For example, it may be used to mean the dimensions of a first element, including an aerosol-forming substrate or a hollow tubular element, in the longitudinal direction.

[0042] The first fold may be the only fold in the sheet. Thus, the first fold may be the only fold along which the supporting elements are subordinate to the surrounding portion.

[0043] The support elements may include the edges of the sheet. The edges of the sheet may be in contact with the surrounding portion. The edges of the sheet may be attached to the surrounding portion by adhesive at the point of contact with the surrounding portion.

[0044] The second portion of the sheet may form part of the peripheral portion of the hollow tubular element.

[0045] The second portion of the sheet may include a second fold. Preferably, the support element is subordinate to the peripheral portion along the second fold of the sheet. Preferably, the support element is subordinate to the peripheral portion along both the first and second folds of the sheet. This provides sufficient mechanical strength and rigidity in one or both of the longitudinal and transverse directions to the hollow tubular structure, preventing or limiting the movement of at least a portion of the first element and at least a portion of any components provided inside it, without the hollow tubular structure deforming significantly during at least one of the handling, transport, and use of the aerosol generating article, for example, during the interaction between the aerosol generating article and the aerosol generating device, particularly during the insertion of the aerosol generating article into the aerosol generating device.

[0046] The second fold may extend along a portion of the length of the hollow tubular element. The second fold may extend along about 10 percent or more of the length of the hollow tubular element, preferably about 40 percent or more, and more preferably about 80 percent or more. Most preferably, the second fold extends along substantially the entire length of the hollow tubular element.

[0047] Preferably, the first and second folds extend by approximately the same amount along the length of the hollow tubular element.

[0048] The first fold and the second fold may be parallel to each other. The first fold and the second fold may be non-parallel to each other.

[0049] The first fold of the sheet and the second fold of the sheet may be spaced apart from each other. The first fold of the sheet and the second fold of the sheet may be spaced apart from each other by about 0.05 mm or more, preferably about 0.3 mm or more, and more preferably about 0.5 mm or more.

[0050] The first fold of the sheet and the second fold of the sheet may be spaced about 3 millimeters or less, preferably about 2.5 millimeters or less, and more preferably about 2 millimeters or less from each other.

[0051] The first fold of the sheet and the second fold of the sheet may be spaced about 0.05 mm to about 3 mm apart from each other, preferably about 0.3 mm to about 2.5 mm, and more preferably about 0.5 mm to about 2 mm apart.

[0052] The first fold of the sheet and the second fold of the sheet may be spaced apart from each other by at least 0.2 percent of the circumference of the hollow tubular element, preferably at least 2 percent of the circumference of the hollow tubular element, and more preferably at least 3 percent of the circumference of the hollow tubular element.

[0053] The first fold of the sheet and the second fold of the sheet may be spaced apart from each other by a distance of no more than about 12 percent around the hollow tubular element, preferably no more than about 10 percent around the hollow tubular element, and more preferably no more than about 8 percent around the hollow tubular element.

[0054] The first fold of the sheet and the second fold of the sheet may be spaced apart from each other by about 0.2 percent to about 12 percent around the hollow tubular element, preferably about 2 percent to about 10 percent around the hollow tubular element, and more preferably about 3 percent to about 8 percent around the hollow tubular element.

[0055] The first fold and the second fold of the sheet can be spaced about half the circumference of the hollow tubular element from each other. That is, the first fold and the second fold of the sheet can be located almost directly opposite each other.

[0056] The first point in the peripheral portion and the second point in the peripheral portion may be spaced apart from each other around the hollow tubular element by about 5 percent to about 50 percent, preferably about 10 percent to about 40 percent, and more preferably about 15 percent to about 30 percent.

[0057] The first fold and the second fold of the sheet may be adjacent to each other. The first fold and the second fold of the sheet may be separated from each other by zero millimeters. The first fold and the second fold of the sheet may be in contact with each other. The first fold and the second fold of the sheet may be glued together. The use of adhesive may help to improve the mechanical strength of the hollow tubular element in one or both of the longitudinal and transverse directions. Thus, this may help to improve the resistance of the hollow tubular element to collapse or deformation.

[0058] The support elements may contact the peripheral portion of the sheet at further points on the peripheral portion other than the first fold and at points on the peripheral portion other than the second fold. If the support elements are in contact with the peripheral portion, the support elements may be attached to the peripheral portion at the contact points by adhesive.

[0059] The support element may include a tip, which is located within a hollow inner region. The tip may be separated from the peripheral portion. The tip may be separated from the peripheral portion by about 0.6 mm or more, preferably about 2 mm or more, and more preferably about 3 mm or more.

[0060] The tip may be located about 0.2 mm or more, preferably about 0.5 mm or more, and more preferably about 1 mm or more, away from the radial center of the hollow tubular element.

[0061] The tip may be separated from the radial center of the hollow tubular element by approximately 3 mm or less, preferably approximately 2.5 mm or less, and more preferably approximately 2 mm or less.

[0062] The tip may be spaced about 0.2 mm to about 3 mm, preferably about 0.5 mm to about 2.5 mm, and more preferably about 1 mm to about 2 mm from the radial center of the hollow tubular element.

[0063] The tip can be spaced approximately 1.5 millimeters away from the radial center of the hollow tubular element.

[0064] The tip may be located at a point adjacent to a point in the peripheral portion. The tip may be in contact with the peripheral portion. The tip may be located at the radial center of the hollow tubular element.

[0065] The tip can be positioned equidistant from the first fold of the sheet and the second fold of the sheet.

[0066] As used herein, the term “radial center” refers to the center of the cross-section of a hollow tubular element.

[0067] The tip may be pointed. For example, the support element may have a substantially triangular cross-section.

[0068] The tip may be rounded. For example, the support element may have a substantially parabolic cross-section.

[0069] The tip may be flat. For example, the support element may have a substantially trapezoidal cross-section.

[0070] The support element may include a third fold in the sheet. That is, the second portion of the sheet may include a third fold between the first fold and the second fold of the sheet. This further strengthens the hollow tubular element in one or both of the longitudinal and transverse directions, enabling it to withstand large forces applied in one or both of the longitudinal and transverse directions before substantially deforming. Thus, this can improve the ability of the hollow tubular element to prevent or limit the movement of at least a portion of the first element of the aerosol-generating article, and at least a portion of any components provided therein.

[0071] A third fold may be located in or adjacent to the peripheral portion. A third fold may be located at or adjacent to the radial center of the hollow tubular element.

[0072] The third fold can define the tip of the support element.

[0073] The third fold may be positioned equidistant from the first and second folds. The third fold may be positioned closer to the first fold than to the second fold.

[0074] It is preferable that there be approximately the same amount of sheet material between the first and third folds as there is between the second and third folds. Alternatively, there may be less sheet material between the first and third folds than there is between the second and third folds.

[0075] The surface of the support element along its longitudinal direction may be substantially planar. Thus, the cross-section of the hollow tubular element may include a line corresponding to the substantially planar surface of the support element along its longitudinal direction. The substantially planar surface may extend from a first fold. If there is a second fold in the sheet, the substantially planar surface may extend to the second fold. If there are both a first and a second fold in the sheet, the substantially planar surface may extend from the first fold to the second fold. If there are both a first and a third fold in the sheet, the substantially planar surface may extend from the first fold to the third fold. If there are both a second and a third fold in the sheet, the substantially planar surface may extend from the second fold to the third fold.

[0076] The support element may include a substantially straight portion when viewed from the upstream end of the hollow tubular element. The substantially straight portion may extend from the first fold of the sheet when viewed from the upstream end of the hollow tubular element. If there is a second fold of the sheet, the substantially straight portion may extend to the second fold when viewed from the upstream end of the hollow tubular element. If there are both a first and a second fold of the sheet, the substantially planar surface may extend from the first fold to the second fold when viewed from the upstream end of the hollow tubular element. If there are both a first and a third fold of the sheet, the substantially straight portion may extend from the first fold to the third fold when viewed from the upstream end of the hollow tubular element. If there are both a second and a third fold of the sheet, the substantially straight portion may extend from the second fold to the third fold when viewed from the upstream end of the hollow tubular element.

[0077] If both a first fold and a third fold are present, the first and third folds may define the first side wall of the support element. That is, the first side wall may extend from the first fold to the third fold, with no folds in between. The first side wall may be substantially straight. The first side wall may be curved.

[0078] The first side wall is completely surrounded by the peripheral portion of the hollow tubular element and therefore does not need to form the outer surface of the hollow tubular element.

[0079] If both a second and a third fold are present, the second and third folds may define a second side wall of the support element. That is, the second side wall may extend from the second fold to the third fold, with no folds in between. The second side wall may be substantially straight. The second side wall may be curved.

[0080] The second side wall is completely enclosed by the peripheral portion of the hollow tubular element and therefore does not need to form the outer surface of the hollow tubular element.

[0081] The first sidewall of the support element may form the outer surface of the hollow tubular element. The second sidewall of the support element may form the outer surface of the hollow tubular element. For example, the entire peripheral portion and the entire support element are integrally formed from the same sheet, substantially the entire peripheral portion and substantially the entire support element are formed from a single layer of sheet (excluding seams), the support element is subordinate to the peripheral portion along both a first fold and a second fold of the sheet, the support element includes a third fold that exists within the hollow inner region of the hollow tubular element, the first and third folds define a substantially straight first sidewall of the support element, the second and third folds define a substantially straight second sidewall of the support element, the first and second sidewalls are centered on the third fold, for example, at an angle of 30 degrees. In this example, the first sidewall forms the outer surface of the hollow tubular element, and the second sidewall forms the outer surface of the hollow tubular element.

[0082] The outer surface of a hollow tubular element may be formed from a peripheral portion, a first side wall of the support element, and a second side wall of the support element.

[0083] If the first side wall is substantially straight and the second side wall is substantially straight, the first and second side walls may define an angle of about 5 degrees or more between them. That is, the angle between the first side wall and the second side wall may be about 5 degrees or more. In other words, the angle centered on the third fold may be about 5 degrees or more. Preferably, the angle between the first side wall and the second side wall at the third fold is about 10 degrees or more, more preferably about 15 degrees or more, and even more preferably about 20 degrees or more.

[0084] If the first side wall is substantially straight and the second side wall is substantially straight, the angle between the first side wall and the second side wall may be about 50 degrees or less, preferably the angle between the first side wall and the second side wall at the third fold is about 45 degrees or less, more preferably about 40 degrees or less, and even more preferably about 35 degrees or less.

[0085] If the first side wall is substantially straight and the second side wall is substantially straight, the angle between the first side wall and the second side wall may be about 5 degrees to about 50 degrees, preferably about 10 degrees to about 45 degrees, more preferably about 15 degrees to about 40 degrees, and even more preferably about 20 degrees to about 35 degrees.

[0086] The surfaces of the first and second side walls may be in contact with each other. The surfaces of the first and second side walls may be attached to each other by adhesive. The substantially entire outer surface of the first and second side walls may be in contact with each other. The substantially entire outer surface of the first and second side walls may be attached to each other by adhesive. The use of adhesive may help to improve the mechanical strength of the hollow tubular element in one or both of the longitudinal and transverse directions. This may thus help to improve the resistance of the hollow tubular element to collapse or deformation, and the ability of the hollow tubular element to prevent or limit the movement of at least a portion of the first element and any components provided inside it. If the first side wall is substantially straight and the second side wall is substantially straight, the angle formed between the first and second side walls may be approximately 0 degrees.

[0087] The cross-section of the support element may include a curved portion. The support element may include a curved portion when viewed from the upstream end of the hollow tubular element. The support element may include a substantially S-shaped cross-section. The support element may be substantially S-shaped when viewed from the upstream end of the hollow tubular element. The support element may include a substantially omega-shaped cross-section. The support element may be substantially omega-shaped when viewed from the upstream end of the hollow tubular element. The support element may include a substantially C-shaped cross-section. The support element may be substantially C-shaped when viewed from the upstream end of the hollow tubular element.

[0088] The support element may have a waveform profile when viewed from the upstream end of the hollow tubular element. The support element may include multiple peaks and troughs when viewed from the upstream end of the hollow tubular element. The support element may be substantially sinusoidal when viewed from the upstream end of the hollow tubular element. The support element may have a substantially triangular waveform profile when viewed from the upstream end of the hollow tubular element. For example, the support element may be substantially W-shaped when viewed from the upstream end of the hollow tubular element.

[0089] The hollow tubular element may include at least one symmetrical longitudinal plane. The hollow tubular element may also be radially symmetric. This can simplify the assembly of the aerosol generating article because the orientation in which the hollow tubular element is inserted into the aerosol generating article is not so important. Furthermore, this also means that the hollow tubular element can distribute the load more evenly and withstand the increased forces applied.

[0090] The cross-sectional area of ​​the hollow tubular element is preferably substantially constant along its entire length. This is because the draw resistance of the aerosol-generating article may also be constant along its entire length.

[0091] It is preferable that a hollow tubular element has a substantially constant cross-section along its entire length. That is, the cross-section of the hollow tubular element does not substantially change along its entire length. This can simplify the manufacturing of the hollow tubular element. The cross-section of a hollow tubular element may change along its length. For example, a support element may have a cross-section that changes along the length of the hollow tubular element. For example, a support element may not extend along the entire length of the hollow tubular element.

[0092] The support element may divide the hollow inner region of the hollow tubular element into multiple channels. The number of channels may be selected based on the desired nucleation of aerosol particles and the desired draw resistance of the aerosol generating article. The support element may divide the cavity of the hollow tubular element into two channels. The support element may divide the cavity of the hollow tubular element into three channels. The support element may divide the cavity of the hollow tubular element into four channels. The support element may divide the cavity of the hollow tubular element into two to four channels. The support element may divide the cavity of the hollow tubular element into at least three channels.

[0093] The support element may extend through the radial center of the hollow tubular element.

[0094] The support element may be located at a distance of approximately 5 percent or more of the radius of the hollow tubular element, preferably approximately 10 percent or more of the radius of the hollow tubular element, and more preferably approximately 15 percent or more of the radius of the hollow tubular element, from the radial center of the hollow tubular element.

[0095] The support element may be located at a distance of approximately 90 percent or less of the radius of the hollow tubular element from the radial center of the hollow tubular element, preferably at a distance of approximately 80 percent or less of the radius of the hollow tubular element from the radial center of the hollow tubular element, and more preferably at a distance of approximately 70 percent or less of the radius of the hollow tubular element from the radial center of the hollow tubular element.

[0096] The support element may be located at a distance from the radial center of the hollow tubular element of approximately 5 percent to 90 percent of the radius of the hollow tubular element, preferably about 10 percent to 80 percent of the radius of the hollow tubular element, and more preferably about 15 percent to 70 percent of the radius of the hollow tubular element.

[0097] The support element may be separated from the radial center of the hollow tubular element by a distance of about 0.2 millimeters or more, and preferably by a distance of about 0.5 millimeters or more, and more preferably about 1 millimeter or more, from the radial center of the hollow tubular element.

[0098] The support element may be located at a distance of approximately 3 millimeters or less, preferably approximately 2.5 millimeters or less, more preferably approximately 2 millimeters or less, or approximately 1 millimeter or less from the radial center of the hollow tubular element.

[0099] The support element may be located about 0.2 mm to 3 mm, preferably about 0.5 mm to 2.5 mm, more preferably about 1 mm to 2 mm, or about 0.5 mm to 1 mm away from the radial center of the hollow tubular element.

[0100] If the support element includes a tip, the support element may have a depth of about 0.6 mm or more, preferably about 1 mm or more, and more preferably about 1.5 mm or more.

[0101] If the support element includes a tip, the support element may have a depth of about 3 mm or less, preferably about 2.7 mm or less, and more preferably about 2.5 mm or less.

[0102] If the support element includes a tip, the support element may have a depth of about 0.6 mm to about 3 mm, preferably about 1 mm to about 2.7 mm, and more preferably about 1.5 mm to about 2.5 mm. If the support element includes a tip, the support element may have a depth of about 2 mm to about 3 mm.

[0103] If the support element includes a tip, the support element may have a depth of approximately 2 millimeters. If the support element includes a tip, the support element may have a depth approximately equal to the inner diameter of the hollow tubular element.

[0104] As used herein, the term "depth" refers to the distance between the first fold and the tip of the support element.

[0105] The support element may be the sole support element of the hollow tubular element; that is, the hollow tubular element may contain a single support element. Alternatively, the support element may be the first support element, and the hollow tubular element may contain one or more additional support elements. Each of the one or more additional support elements may be formed from a sheet. Each of the one or more additional support elements may be formed from a separate sheet. Preferably, the one or more additional support elements are formed from the same sheet as the first support element. Each of the one or more additional support elements may extend from each first fold of the peripheral portion into the hollow inner region.

[0106] Each of the one or more additional support elements may be subordinate to the peripheral portion along each second fold of the sheet.

[0107] The hollow tubular element may include two to six support elements. Preferably, the hollow tubular element includes three support elements. Three support elements may help improve the hollow tubular element's resistance to collapse or deformation, and its ability to prevent or limit the movement of at least a portion of the aerosol-forming substrate.

[0108] Each of the support elements may be identical to one another. This may simplify the manufacturing of the hollow tubular element. One of the support elements may be different from another. For example, the first support element may be larger in size than the second support element.

[0109] Each support element may have any combination of the features described above with respect to the support element, i.e., the first support element.

[0110] Each of the support elements can be spaced almost equally around the periphery of the hollow tubular element. That is, the distance between the first fold on which one support element extends and the first fold on which the next support element extends is approximately the same around the periphery of the hollow tubular element.

[0111] If the support elements are identical to each other and evenly spaced around the periphery of the hollow tubular element, the hollow tubular element may exhibit radial symmetry. This can simplify the assembly of the aerosol generating article because the orientation in which the hollow tubular element is inserted into the aerosol generating article is less important. Furthermore, this also means that the hollow tubular element can distribute the load more evenly and withstand the increased forces applied.

[0112] The hollow tubular element may have a length of about 4 mm or more, preferably about 6 mm or more, and more preferably about 8 mm or more.

[0113] The hollow tubular element may have a length of about 40 mm or less, preferably about 30 mm or less, and more preferably about 20 mm or less.

[0114] The hollow tubular elements may have a length of about 4 mm to about 40 mm, preferably about 6 mm to about 30 mm, and more preferably about 8 mm to about 20 mm.

[0115] The hollow tubular element may have a length of approximately 8 millimeters. The hollow tubular element may have a length of approximately 18 millimeters.

[0116] The hollow tubular element preferably has an outer diameter approximately equal to the outer diameter of the aerosol generating article comprising the hollow tubular element. If the first element of the aerosol generating article is formed as a rod, it is preferable that the hollow tubular element has an outer diameter approximately equal to the outer diameter of the first element.

[0117] The hollow tubular element may have an outer diameter of about 5 mm or more, preferably about 6 mm or more, and more preferably about 7 mm or more.

[0118] The hollow tubular element may have an outer diameter of about 12 mm or less, preferably about 10 mm or less, and more preferably about 8 mm or less.

[0119] The hollow tubular element may have an outer diameter of about 5 mm to about 12 mm, preferably about 6 mm to about 10 mm, and more preferably about 7 mm to about 8 mm.

[0120] The hollow tubular element may have an outer diameter of approximately 7.2 millimeters.

[0121] The hollow tubular element may have an inner diameter of about 4.5 mm or more, preferably about 5.5 mm or more, and more preferably about 6.5 mm or more.

[0122] The hollow tubular element may have an inner diameter of about 11.5 mm or less, preferably about 9.5 mm or less, and more preferably about 7.5 mm or less.

[0123] The hollow tubular element may have an inner diameter of about 4.5 mm to about 11.5 mm, preferably about 5.5 mm to about 9.5 mm, and more preferably about 6.5 mm to about 7.5 mm.

[0124] The hollow tubular element may have a total internal surface area of ​​about 25 square millimeters or more per millimeter length, preferably about 28 square millimeters or more per millimeter length, more preferably about 30 square millimeters or more per millimeter length, or about 35 square millimeters or more per millimeter length.

[0125] The hollow tubular element may have a total internal surface area of ​​about 70 square millimeters or less per millimeter length, preferably about 60 square millimeters or less per millimeter length, more preferably about 50 square millimeters or less per millimeter length, or about 40 square millimeters or less per millimeter length.

[0126] The hollow tubular element may have a total internal surface area of ​​about 25 square millimeters to about 70 square millimeters per millimeter, preferably about 28 square millimeters to about 60 square millimeters per millimeter, more preferably about 30 square millimeters to about 50 square millimeters per millimeter, or about 30 square millimeters to about 40 square millimeters per millimeter. The hollow tubular element may have a total internal surface area of ​​about 35 square millimeters to about 70 square millimeters per millimeter, preferably about 40 square millimeters to about 70 square millimeters per millimeter, more preferably about 50 square millimeters to about 70 square millimeters per millimeter, or about 60 square millimeters to about 70 square millimeters per millimeter.

[0127] Preferably, the hollow tubular element provides an unrestricted flow channel. This means that the hollow tubular segment preferably provides a negligible level of drawdown resistance (RTD). The term “negligible level of RTD” is used to refer to an RTD of less than 1 mmH2O per 10 mm of length of the hollow tubular element, preferably less than 0.4 mmH2O per 10 mm of length of the hollow tubular element, and more preferably less than 0.1 mmH2O per 10 mm of length of the hollow tubular element. Therefore, the flow channel should not contain any components that would obstruct the longitudinal airflow. The flow channel is preferably substantially empty.

[0128] Unless otherwise specified, the draw resistance (RTD) of a component or aerosol-generating article shall be measured in accordance with ISO 6565-2015. RTD refers to the pressure required to force air through the entire length of the component. The terms “pressure drop” or “draw resistance” of a component or article may also refer to “resistance to draw.” These terms generally refer to the fact that the measurement in accordance with ISO 6565-2015 is successfully performed under a test of a volumetric flow rate of approximately 17.5 milliliters per second at the output 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%.

[0129] The hollow tubular element may have a void ratio of about 80 percent or more in the longitudinal direction, preferably about 90 percent or more in the longitudinal direction, and more preferably about 95 percent or more in the longitudinal direction.

[0130] The hollow tubular element may have a porosity of about 80 percent to about 99 percent in the longitudinal direction, or about 85 percent to about 95 percent in the longitudinal direction, or about 90 percent to about 95 percent in the longitudinal direction. Preferably, the hollow tubular element has a porosity of about 95 percent to about 99.9 percent in the longitudinal direction, or about 96 percent to about 99.5 percent in the longitudinal direction, about 97 percent to about 99 percent in the longitudinal direction, or about 98 percent in the longitudinal direction. As used herein, the porosity of the hollow tubular element in the longitudinal direction is defined by the ratio of the cross-sectional area of ​​the material forming the hollow tubular element to the internal cross-sectional area of ​​the aerosol-generating article at the location of the hollow tubular element.

[0131] The longitudinal porosity of the hollow tubular element can be advantageously selected to provide the desired overall draw resistance of the aerosol-generating article.

[0132] The longitudinal porosity of a hollow tubular element may be substantially constant along its entire length. For example, the cross-sectional area of ​​the material forming the hollow tubular element may be substantially constant along its entire length, and the aerosol-generating article may also have a substantially constant internal cross-sectional area along its entire length. A hollow tubular element may have a substantially constant cross-sectional area along its entire length, such that the cross-sectional area of ​​the material forming the hollow tubular element is substantially constant along its entire length. A hollow tubular element may also have a cross-sectional area that varies along the length of the hollow tubular element, and a substantially constant cross-sectional area of ​​the material forming the hollow tubular element along its entire length.

[0133] The longitudinal porosity of a hollow tubular element may vary along its length. For example, this may be the case when a hollow tubular element does not have a constant cross-section along its entire length, such that the cross-sectional area of ​​the material forming the hollow tubular element varies along its length.

[0134] The sheet, comprising the first and second parts, may be formed from paper, any other paper-based material, any other cellulosic material, bioplastic material, or metal. For example, the sheet may be formed from one or more of the following: paper, cardboard, corrugated cardboard, reconstituted tobacco paper, cellophane, and aluminum.

[0135] The sheet is preferably formed from a biodegradable material.

[0136] Most preferably, the sheet is formed from a paper-based material such as paper, cardboard, or corrugated cardboard. The paper-based material may be bleached or unbleached. The paper-based material may be lightweight, inexpensive, and biodegradable. If the sheet is a paper sheet, the hollow tubular elements may prevent or restrict the movement of at least a portion of the first elements of the aerosol generating article and any components provided inside them, while exhibiting sufficient mechanical strength and rigidity to withstand large deformations during at least one of the handling, transport, and use of the aerosol generating article, for example, during the interaction between the aerosol generating article and the aerosol generating device. The interaction may include inserting the aerosol generating article into the aerosol generating device. The material properties of the paper sheet may be such that individual hollow tubular elements formed from the paper sheet can be cut from a continuous rod of hollow tubular elements. This may simplify the manufacture of the hollow tubular elements.

[0137] Aluminum has a very high ignition temperature. Therefore, hollow tubular elements formed from aluminum sheets can help prevent the hollow tubular elements from igniting at the temperature reached by aerosol-generating articles containing the hollow tubular elements during use.

[0138] The sheets forming one or both of the peripheral portion and the support element may have a basis weight of about 15 grams / m² or more, preferably about 25 grams / m² or more, more preferably about 35 grams / m² or more, or about 45 grams / m² or more. Sheets having such a basis weight can avoid cracking and / or fracture during bending and / or folding of the sheet. Thus, when bent or folded to form the support element, the sheet can maintain its structural integrity. This can improve the resistance of the hollow tubular element to collapse or deformation, and the ability of the hollow tubular element to prevent or limit the movement of at least a portion of the aerosol-forming substrate and at least a portion of the susceptor element.

[0139] The sheets forming one or both of the peripheral portion and the support element may have a basis weight of about 150 grams / m² or less, preferably about 130 grams / m² or less, more preferably about 110 grams / m² or less, or about 80 grams / m² or less, or about 50 grams / m² or less. By providing sheets having such basis weights, it is advantageous that the hollow tubular elements may have a desired porosity in the longitudinal direction. This may be such that the hollow tubular elements have a desired draw resistance. Furthermore, by providing sheets having such basis weights, it is advantageous that the manufacture of the hollow tubular elements may be facilitated, for example, by making it easy to roll, bend, and fold the sheet.

[0140] The sheets may have a basis weight of approximately 15 grams / square meter to approximately 150 grams / square meter, approximately 20 grams / square meter to approximately 130 grams / square meter, approximately 60 grams / square meter to approximately 100 grams / square meter, or approximately 70 grams / square meter to approximately 80 grams / square meter.

[0141] The sheet preferably has a basis weight of about 45 grams / square meter to about 110 grams / square meter. The sheet may have a basis weight of about 45 grams / square meter. The sheet may have a basis weight of about 60 grams / square meter. Preferably, the sheet has a basis weight of about 78 grams / square meter. Preferably, the sheet has a basis weight of about 110 grams / square meter.

[0142] The sheets may have thicknesses of approximately 15 micrometers or more, approximately 30 micrometers or more, approximately 45 micrometers or more, and approximately 100 micrometers or more. Sheets of such thicknesses can avoid crack formation and / or fracture during bending and / or folding of the sheet. Thus, when bent or folded to form a support element, the sheet can maintain its structural integrity. This can improve the resistance of the hollow tubular element to collapse or deformation, and the ability of the hollow tubular element to prevent or limit the movement of at least a portion of the first element and one or both of any components provided inside it.

[0143] The sheet may have a thickness of about 150 micrometers or less, preferably about 140 micrometers or less, and more preferably about 130 micrometers or less. By providing a sheet having such a thickness, it is advantageous that the hollow tubular elements may have a desired porosity in the longitudinal direction. This may be such that the hollow tubular elements have a desired draw resistance. Furthermore, by providing a sheet having such a basis weight, it is advantageous that the manufacture of the hollow tubular elements may be facilitated, for example, by making it easy to roll, bend, and fold the sheet.

[0144] The sheet may have a thickness of about 15 micrometers to about 150 micrometers, preferably about 30 micrometers to about 140 micrometers, and more preferably about 100 micrometers to about 130 micrometers.

[0145] If the sheet is an aluminum sheet, the sheet may have a thickness of about 10 to 20 micrometers. Aluminum sheets of such thickness can be advantageous in that they facilitate the manufacture of hollow tubular elements, for example, by allowing the sheet to be easily rolled, bent, and folded. Furthermore, aluminum sheets of such thickness can prevent deformation of the hollow tubular element while providing the hollow tubular element with sufficient strength and rigidity to prevent or limit the movement of at least a portion of the first element and one or both of any components provided inside it. Moreover, aluminum sheets of such basis weight can be advantageous in that they can ensure that the hollow tubular element has a desired porosity in the longitudinal direction.

[0146] The support element may be substantially as a whole, formed from a single layer of sheets that make up the support element. In this case, the support element may be substantially as thick as the thickness of the sheet. The support element may include seams, which may be formed from overlapping layers of sheets. The overlapping layers of sheets forming the seams may be joined to each other by adhesive.

[0147] At least a portion of the peripheral portion may be formed from a single layer of sheets. Substantially the entire peripheral portion may be formed from a single layer of sheets. At least a portion of the peripheral portion may be formed from multiple overlapping layers of sheets, such as multiple parallel-wound layers of sheets or multiple helical-wound layers of sheets. For example, a portion of the peripheral portion may be formed from a first portion of a sheet and further layers of sheets, with the first portion of the sheet forming the outermost layer of that portion of the peripheral portion. That is, there is no layer of sheets covering the first portion of the sheet, and as a result, the entire first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element. If the peripheral portion includes a seam, the seam may be formed from overlapping layers of sheets. For example, the majority of the peripheral portion may be formed from a single layer of sheets, and the seam may be formed from two overlapping layers of sheets.

[0148] If the peripheral portion is formed from a single layer of sheets, the peripheral portion will have approximately the same thickness as the sheet.

[0149] A hollow tubular element can be formed from a single sheet. A hollow tubular element can be formed from multiple sheets.

[0150] The peripheral portion may be formed from multiple sheets. For example, the peripheral portion may be formed from both the sheet forming the support element and additional sheets.

[0151] The peripheral portion may be formed from a total of four layers, or one or more sheets, that make up the peripheral portion. If a portion of the peripheral portion includes multiple layers, and one of the layers is formed by a first portion of a sheet that forms a support element, then the first portion of the sheet that forms the support element forms the outermost layer of that portion of the peripheral portion.

[0152] A section of the peripheral portion may be formed from a different number of sheets from further sections of the peripheral portion. For example, a section of the peripheral portion may be formed from one sheet, and an additional section of the peripheral portion may be formed from two sheets. Another example is that a section of the peripheral portion may be formed from two sheets, an additional section of the peripheral portion may be formed from three sheets, and further sections of the peripheral portion may be formed from four sheets.

[0153] The peripheral portion may have a thickness of approximately 15 micrometers or more, approximately 45 micrometers or more, or approximately 100 micrometers or more. By providing a peripheral portion with such thickness, the hollow tubular element is provided with sufficient strength and rigidity to prevent or limit the movement of one or both of the first element and the susceptor element, while deformation of the hollow tubular element can be prevented.

[0154] The peripheral portion may have a thickness of approximately 600 micrometers or less, approximately 500 micrometers or less, or approximately 400 micrometers or less. By providing peripheral portions with such thicknesses, it is advantageous that the hollow tubular element can be ensured to have a desired porosity in the longitudinal direction. This may result in the hollow tubular element having a desired draw resistance. Furthermore, providing peripheral portions with such thicknesses may mean that individual hollow tubular elements can be easily cut from a continuous rod of hollow tubular elements. This may simplify the manufacturing of the hollow tubular elements.

[0155] The peripheral portion may have a thickness of approximately 15 micrometers to approximately 600 micrometers, approximately 50 micrometers to approximately 500 micrometers, or approximately 100 micrometers to approximately 400 micrometers. Preferably, the peripheral portion has a thickness of approximately 100 micrometers to 130 micrometers.

[0156] Hollow tubular elements with a low total weight have the advantage of being able to be assembled into aerosol-generating articles using high-speed machinery and processes. In particular, the inventors of the present invention have found that hollow tubular elements with a total weight of about 150 milligrams or less can, advantageously, be assembled into aerosol-generating articles using existing high-speed aerosol-generating article assembly machines.

[0157] The hollow tubular element may have a total weight of about 150 milligrams or less, preferably about 100 milligrams or less, and more preferably about 70 milligrams or less.

[0158] The hollow tubular elements may have a total weight of about 15 milligrams to about 150 milligrams, preferably about 20 milligrams to about 100 milligrams, and about 25 milligrams to about 70 milligrams.

[0159] The hollow tubular element may have a total weight of approximately 34 milligrams. The hollow tubular element may have a total weight of approximately 76 milligrams.

[0160] The hollow tubular elements may have an average weight of about 10 milligrams or less per millimeter of length, preferably 8 milligrams or less per millimeter of length, and more preferably about 6 milligrams or less per millimeter of length. By providing hollow tubular elements having such an average weight, it may be advantageous to assemble the hollow tubular elements into the aerosol generating article using existing high-speed aerosol generating article assembly machines.

[0161] The hollow tubular elements may have an average weight of about 1 to about 10 milligrams per millimeter length of the hollow tubular element, preferably about 2.5 to about 8 milligrams per millimeter length of the hollow tubular element, and more preferably about 2 to about 6 milligrams per millimeter length of the hollow tubular element.

[0162] The hollow tubular element may have an average weight of approximately 4.25 milligrams per millimeter of length.

[0163] As used herein, the average weight of a hollow tubular element is measured by dividing the total weight of the hollow tubular element by the length of the hollow tubular element.

[0164] The hollow tubular element may include a flame-retardant portion containing a flame-retardant composition. For example, one or both of the support element and / or peripheral portion may include a flame-retardant portion. The sheet forming the support element may include a flame-retardant portion. If the peripheral portion is formed from a sheet, the sheet forming the peripheral portion may also include a flame-retardant portion. The flame-retardant portion can prevent one or both of the hollow tubular element from charring and / or carbonizing during use of an aerosol-generating article comprising the hollow tubular element. This is because, by providing one or more flame-retardant compounds to the hollow tubular element, it is possible to substantially prevent any heat transferred to the hollow tubular element from causing thermal decomposition or combustion of the hollow tubular element.

[0165] The flame-retardant portion can avoid the need for additional layers of metal foil or other heat shielding material contained in one or both of the hollow tubular elements and the aerosol-generating articles. This simplifies the manufacturing process and therefore can reduce manufacturing costs. Furthermore, it can make the disposal of used aerosol-generating articles easier, as there is no need to separate and recover valuable recyclable materials such as aluminum foil when the articles are discarded.

[0166] As used herein, the term "flame-retardant composition" means a composition comprising one or more flame-retardant compounds.

[0167] As used herein, the term “flame retardant compound” refers to a chemical compound that, when added to or otherwise incorporated into a substrate such as paper or plastic compounds, provides the substrate with varying degrees of flammability protection. In practice, flame retardant compounds may be activated by the presence of an ignition source and are adapted to prevent or slow the further progression of ignition through a variety of different physical and chemical mechanisms.

[0168] The flame retardant composition may comprise a polymer and a mixed salt based on at least one mono, di, and / or tricarboxylic acid, at least one polyphosphate, pyrophosphate, and / or phosphoric acid, and a hydroxide or alkali or alkaline earth metal salt, wherein at least one mono, di, and / or tricarboxylic acid and the hydroxide or salt form a carboxylate and at least one polyphosphate, and the pyrophosphate and / or phosphoric acid and the hydroxide or salt form a phosphate.

[0169] The flame retardant composition contains at least one C 10 The above fatty acids may include cellulose modified with tall oil fatty acids (TOFA), phosphorylated linseed oil, and phosphorylated downstream corn oil. Preferably, at least one C 10 The above fatty acids are selected from the group consisting of capric acid, myristic acid, palmitic acid, and combinations thereof.

[0170] A portion of the hollow tubular element may be enclosed by a wrapper. The entire hollow tubular element may be enclosed by a wrapper. The wrapper may be a paper wrapper.

[0171] The hollow tubular element is preferably connected to one or more adjacent components of the aerosol-generating article by a wrapper. The wrapper may be a paper wrapper.

[0172] The aerosol-generating article may include a susceptor element. The susceptor element may be disposed within a first element. The susceptor element may be disposed within an aerosol-forming substrate. The susceptor element may be disposed around an aerosol-forming substrate.

[0173] If an aerosol-generating article includes a susceptor element, a support element may act to provide a support barrier for at least a portion of the susceptor element. This can help prevent or limit the movement of at least a portion of the susceptor element during at least one of the handling, use, and transport of the aerosol-generating article. The movement of a portion of the susceptor element can have a greater negative impact on the performance of the aerosol-generating article than the movement of a portion of the aerosol-forming substrate. This is because the movement of a portion of the susceptor element can affect one or both of the ability of the susceptor element to be inductively heated and the ability of the susceptor element to heat the aerosol-forming substrate during use of the aerosol-generating article. Therefore, preventing or limiting the movement of at least a portion of the susceptor element can have a significant impact on the user experience. Thus, preventing or limiting the movement of at least a portion of the susceptor element can result in a more consistent experience for the user.

[0174] When an aerosol-generating article includes a susceptor element, preventing or limiting the movement of at least a portion of the aerosol-forming substrate and at least a portion of the susceptor element, or both, can help increase the consistency of the interaction between the aerosol-forming substrate and the susceptor element. This allows the susceptor element to heat the aerosol-forming substrate in a more consistent manner when the aerosol-generating article is in use, which can also result in a more consistent experience for the user.

[0175] As used herein, the term “susceptor element” refers to a material capable of converting electromagnetic energy into heat. When located within a fluctuating electromagnetic field, induced eddy currents within a susceptor element cause the susceptor element to heat up.

[0176] If the aerosol-generating article includes a susceptor element, the susceptor element may be configured to be in thermal contact with the aerosol-forming substrate. Therefore, the aerosol-forming substrate may be heated by the susceptor element during use of the aerosol-generating article.

[0177] The susceptor element may be an elongated susceptor element. The susceptor element may extend longitudinally within the aerosol-forming substrate.

[0178] When used to describe a susceptor element, the term "elongated" means that the susceptor element has a length dimension that is greater than its width dimension or thickness dimension, for example, greater than twice its width dimension or thickness dimension.

[0179] The susceptor element may be substantially longitudinally arranged within the first element. This means that the length dimension of the elongated susceptor element may be positioned such that it is substantially parallel to the longitudinal direction of the first element, for example, within ±10 degrees of parallelism to the longitudinal direction of the first element. Preferably, the elongated susceptor element is positioned at the radial center within the first element and extends along the longitudinal direction of the first element.

[0180] Preferably, the susceptor element extends entirely to the downstream end of the first element. The susceptor element may extend entirely to the upstream end of the first element. Preferably, the susceptor element has substantially the same length as the first element and extends from the upstream end of the first element to the downstream end of the first element.

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

[0182] The susceptor element preferably has a length of about 5 mm to about 15 mm, such as about 6 mm to about 12 mm or about 8 mm to about 10 mm.

[0183] The susceptor element preferably has a width of about 1 mm to about 5 mm.

[0184] The susceptor element may generally have a thickness of about 0.01 mm to about 2 mm, for example, about 0.5 mm to about 2 mm. The susceptor element may also have a thickness of about 10 micrometers to about 500 micrometers, and more preferably, about 10 micrometers to about 100 micrometers.

[0185] If the susceptor element has a certain cross-section, for example a circular cross-section, it has a preferred width or diameter of about 1 mm to about 5 mm.

[0186] If the susceptor element has the form of a strip or blade, the strip or blade preferably has a rectangular shape with a width of about 2 mm to about 8 mm, more preferably about 3 mm to about 5 mm. As an example, a susceptor element in the form of a blade strip may have a width of about 4 mm.

[0187] If the susceptor element has the form of a strip or blade, the strip or blade is preferably rectangular in shape and has a thickness of about 0.03 mm to about 0.15 mm, more preferably about 0.05 mm to about 0.09 mm. As an example, a susceptor element in the form of a blade strip may have a thickness of about 0.06 mm or 0.07 mm.

[0188] Preferably, the elongated susceptor element is in the form of a strip or blade, has a rectangular shape, and has a thickness of about 55 micrometers to about 65 micrometers.

[0189] Preferably, the elongated susceptor element has a length equal to or shorter than the length of the aerosol-forming substrate. Preferably, the elongated susceptor element has the same length as the aerosol-forming substrate.

[0190] The susceptor element can be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from the aerosol-forming substrate. Preferred susceptor elements include metals or carbon.

[0191] Preferred susceptor elements may include or consist of ferromagnetic materials such as ferromagnetic alloys, ferrite iron, or ferromagnetic steel or stainless steel. Suitable susceptor elements may be aluminum or contain aluminum. Preferred susceptor elements may be formed from 400 series stainless steel, such as grade 410, or grade 420, or grade 430 stainless steel. Different materials dissipate different amounts of energy when positioned in an electromagnetic field having similar values ​​of frequency and magnetic field strength.

[0192] Thus, any of the parameters of the susceptor element, such as the type of material, length, width, and thickness, can be varied to provide the desired power distribution within a known electromagnetic field. A preferred susceptor element may be heated to a temperature above 250 degrees Celsius.

[0193] The susceptor element is positioned in thermal contact with the aerosol-forming substrate. Thus, when the temperature of the susceptor element increases, the aerosol-forming substrate is heated, and an aerosol is formed. Preferably, the susceptor element is positioned, for example, within the aerosol-forming substrate, in direct physical contact with the aerosol-forming substrate.

[0194] The susceptor element may be a multi-material susceptor element and may comprise a first susceptor element material and a second susceptor element material. The first susceptor element material may be physically placed in close contact with the second susceptor element material.

[0195] The hollow tubular element may contain adhesive.

[0196] As an example, a first fold and a second fold may be attached to each other by adhesive. For example, a first portion of a sheet forming at least a part of a peripheral portion may be attached to the rest of the peripheral portion by adhesive. As a further example, if a support element is in contact with a peripheral portion, the support element may be attached to the peripheral portion at the point of contact by adhesive. For example, if the support element includes the edge of a sheet, the edge of the sheet may be attached to the peripheral portion by adhesive. As an additional example, a point on the support element may be attached to another point on the support element. For example, if the support element includes a first side wall and a second side wall, the first side wall may be attached to the second side wall by adhesive. Furthermore, if a hollow tubular element includes a seam formed from overlapping layers of sheets, the overlapping layers of sheets may be attached to each other by adhesive to form a seam. Furthermore, if a hollow tubular element is formed from one or more sheets, the one or more sheets may be attached to each other at the point of contact, for example, using adhesive.

[0197] The adhesive may contain at least one of PVA, PVOH, and hot melt glue.

[0198] The adhesive may contain a binder. Suitable binders include, but are not limited to, gums such as guar gum, xanthan gum, gum arabic, and locust bean gum; cellulose binders such as hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, and ethyl cellulose; polysaccharides such as starch, organic acids such as alginic acid, sodium alginate, agar, and conjugated base salts of organic acids such as pectin, and combinations thereof. Preferably, the binder contains guar gum.

[0199] In an aerosol-generating article, the hollow tubular element may be aligned longitudinally with the first element. In particular, the hollow tubular element may be aligned longitudinally with the aerosol-forming substrate. If the aerosol-generating article includes a susceptor element, the hollow tubular element may be aligned longitudinally with the susceptor element.

[0200] The hollow tubular element may be positioned immediately downstream of the first element. This means that there are no other elements of the aerosol-generating article positioned between the hollow tubular element and the first element. This may help improve the ability of the hollow tubular element to prevent or limit the movement of at least a portion of the first element and any components provided therein.

[0201] The hollow tubular element may be in contact with the first element. For example, the upstream end of the hollow tubular element may be in contact with the downstream end of the first element. That is, the upstream end of the hollow tubular element may be in contact with the downstream end of the first element. In particular, the upstream end of the hollow tubular element may be in contact with the downstream end of the aerosol-forming substrate. That is, the upstream end of the hollow tubular element may be in contact with the downstream end of the aerosol-forming substrate.

[0202] The hollow tubular element is positioned immediately downstream of the first element, but does not need to be in contact with the first element, as a small gap of empty space separates the hollow tubular element from the first element in the longitudinal direction of the aerosol-generating article. For example, the hollow tubular element is positioned immediately downstream of the aerosol-forming substrate, but does not need to be in contact with the aerosol-forming substrate. The gap may be about 2 millimeters or less, preferably 1 millimeter or less.

[0203] The first element can be called the aerosol-generating element.

[0204] Aerosol-forming substrates can also be called aerosol-generating substrates.

[0205] The aerosol-forming substrate can substantially define the structure and dimensions of the first element. The aerosol-forming substrate may be a solid aerosol-forming substrate. The aerosol-forming substrate may be in the form of a rod.

[0206] Preferably, the aerosol-forming substrate includes homogenized plant material, preferably homogenized tobacco material.

[0207] As used herein, the term “homogenized plant material” encompasses any plant material formed by the aggregation of plant particles. For example, a sheet or web of homogenized tobacco material for the aerosol-forming substrate of the present invention may be formed by aggregating plant material and, optionally, tobacco material particles obtained by grinding, crushing, or pulverizing one or more of tobacco leaf laminas and tobacco leaf stems. The homogenized plant material may be produced by casting, extrusion, papermaking processes, or any other suitable process known in the art.

[0208] Homogenized plant material may be provided in any suitable form. For example, homogenized plant material may be in the form of one or more sheets. Homogenized plant material may be in the form of multiple pellets or granules. Homogenized plant material may be in the form of multiple strands, strips, or fragments. As used herein, the term “strand” describes an elongated element of material having a length substantially greater than its width and thickness. The term “strand” should be considered to encompass strips, fragments, and any other homogenized plant material having a similar form. Strands of homogenized plant material may be formed from sheets of homogenized plant material, for example, by cutting or dicing, or by other means, such as by extrusion.

[0209] The aerosol-forming substrate is preferably in the form of one or more sheets of homogenized plant material. One or more sheets of homogenized plant material may be produced by a casting process. One or more sheets of homogenized plant material may be produced by a papermaking process. Each of the one or more sheets described herein may individually have a thickness of 100 to 600 micrometers, preferably 150 to 300 micrometers, and most preferably 200 to 250 micrometers. The individual thickness refers to the thickness of the individual sheet, and the combined thickness refers to the total thickness of all sheets constituting the aerosol-forming substrate. For example, if the aerosol-forming substrate is formed from two individual sheets, the combined thickness is the thickness of the two individual sheets, or the sum of the measured thicknesses of the two sheets, and the two sheets are stacked in the aerosol-forming substrate.

[0210] Each of the one or more sheets described herein is individually approximately 100 g / m² 2 ~about 300g / m 2 It may have a basis weight of [a certain amount].

[0211] Each of the sheets described herein is individually approximately 0.3 g / cm² 3~Approx. 1.3g / cm 3 It may have a density of approximately 0.7 g / cm³. 3 ~Approx. 1.0g / cm 3 It is preferable that it has a density of [value missing].

[0212] If the aerosol-forming substrate includes one or more sheets of homogenized plant material, the sheets are preferably in the form of an aggregate of one or more sheets. As used herein, the term “aggregate” means that the sheets of homogenized plant material are spiraled, folded, or otherwise compressed or shrunk substantially transversely to the cylindrical axis of the plug or rod.

[0213] One or more sheets of homogenized plant material may be assembled transversely to their longitudinal axis and surrounded by a wrapper to form a continuous rod or plug.

[0214] One or more sheets of homogenized plant material may, advantageously, be crimped or similarly treated. As used herein, the term “crimped” means a sheet having multiple substantially parallel ridges or undulations. In addition to or otherwise than crimping, one or more sheets of homogenized plant material may be embossed, debossed, perforated, or otherwise deformed to provide texture on one or both sides of the sheet.

[0215] Preferably, each sheet of homogenized plant material can be crimped to have multiple ridges or undulations substantially parallel to the cylindrical axis of the plug. This process advantageously facilitates the assembly of the crimped sheets of homogenized plant material to form the plug. Preferably, one or more sheets of homogenized plant material can be assembled. Naturally, the crimped sheets of homogenized plant material may, by other means or additionally, have multiple substantially parallel ridges or undulations that form acute or obtuse angles with respect to the cylindrical axis of the plug. The sheets may be crimped to such an extent that the integrity of the sheet is interrupted at the multiple parallel ridges or undulations, causing separation of the material and resulting in the formation of fragments, strands, or shards of homogenized plant material.

[0216] One or more sheets of homogenized plant material may be cut into strands as described above. The aerosol-forming substrate may contain multiple strands of homogenized plant material. The strands may be used to form a plug. Preferably, the multiple strands are aligned with the longitudinal axis and extend substantially along the length of the aerosol-forming substrate in the longitudinal direction. Therefore, it is preferable that the multiple strands are aligned substantially parallel to one another.

[0217] The homogenized plant material may contain up to about 95 weight percent of plant particles on a dry weight basis. Preferably, the homogenized plant material contains up to about 90 weight percent of plant particles on a dry weight basis, more preferably about 80 weight percent of plant particles, more preferably about 70 weight percent of plant particles, more preferably about 60 weight percent of plant particles, and more preferably about 50 weight percent of plant particles.

[0218] For example, homogenized plant material may contain, on a dry weight basis, approximately 2.5 to 95 percent by weight of plant particles, or approximately 5 to 90 percent by weight of plant particles, or approximately 10 to 80 percent by weight of plant particles, or approximately 15 to 70 percent by weight of plant particles, or approximately 20 to 60 percent by weight of plant particles, or approximately 30 to 50 percent by weight of plant particles.

[0219] The homogenized plant material may be a homogenized tobacco material containing tobacco particles. The sheet of homogenized tobacco material used in such embodiments may have a tobacco content of at least about 40 weight percent on a dry weight basis, more preferably at least about 50 weight percent on a dry weight basis, more preferably at least about 70 weight percent on a dry weight basis, and most preferably at least about 90 weight percent on a dry weight basis.

[0220] The term "tobacco particles" refers to particles of any plant member of the genus Nicotiana. The term "tobacco particles" includes crushed or powdered tobacco leaf lamina, crushed or powdered tobacco leaf stems, tobacco dust, tobacco fine powder, and other particulate tobacco by-products formed during the processing, handling, and shipping of tobacco. Preferably, tobacco particles are substantially all derived from tobacco leaf lamina. In contrast, separated nicotine and nicotine salts, although compounds derived from tobacco, are not considered tobacco particles for the purposes of this invention and are not included in the proportion of particulate plant material.

[0221] Tobacco particles may be prepared from one or more varieties of tobacco plants. Any type of tobacco may be used in the blend. Examples of types of tobacco materials that may be used include, but are not limited to, sun-dried tobacco, fire-dried tobacco, Burley tobacco, Maryland tobacco, Oriental tobacco, Virginia tobacco, and other specialty tobaccos.

[0222] Tobacco particles may have a nicotine content of at least about 2.5 weight percent based on dry weight. More preferably, tobacco particles may have a nicotine content of at least about 3 weight percent based on dry weight, even more preferably at least about 3.2 weight percent, even more preferably at least about 3.5 weight percent, and most preferably at least about 4 weight percent.

[0223] The homogenized plant material may contain tobacco particles combined with non-tobacco plant flavor particles.

[0224] The weight ratio of non-tobacco plant-flavored particles to tobacco particles in the particulate plant material forming the homogenized plant material may vary depending on the desired flavor characteristics and composition of the aerosol generated from the aerosol-forming substrate during use.

[0225] Homogenized plant material may contain cannabis particles. The term "cannabis particles" refers to particles from cannabis plants such as Cannabis sativa, Cannabis indica, and Cannabis ruderalis.

[0226] The homogenized plant material preferably contains 95% by weight or less of particulate plant material on a dry weight basis. Thus, the particulate plant material is typically combined with one or more other components to form the homogenized plant material.

[0227] Homogenized plant material may further contain a binder for altering the mechanical properties of particulate plant material, wherein the binder is included in the homogenized plant material during production as described herein. The binder is an exogenous binder. Suitable exogenous binders known to those skilled in the art include, but are not limited to, gums such as guar gum, xanthan gum, gum arabic, and locust bean gum; cellulose binders such as hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, and ethyl cellulose; polysaccharides such as starch, organic acids such as alginic acid, conjugated base salts of organic acids such as sodium alginate, agar, and pectin, and combinations thereof. Preferably, the binder includes guar gum.

[0228] The binder may be present in an amount of about 1% to about 10% by weight, preferably about 2% to about 5% by weight, based on the dry weight of the homogenized plant material.

[0229] The homogenized plant material may further contain one or more lipids to facilitate the diffusion of volatile components (e.g., aerosol-forming agents, gingerol, and nicotine), wherein the lipids are included in the homogenized plant material during the manufacturing process described herein. Suitable lipids to be included in the homogenized plant material include, but are not limited to, medium-chain triglycerides, cocoa butter, palm oil, palm kernel oil, mango oil, shea butter, soybean oil, cottonseed oil, coconut oil, hydrogenated coconut oil, candelilla wax, carnauba wax, shellac, sunflower wax, sunflower oil, rice bran, and Revel A, as well as combinations thereof.

[0230] The homogenized plant material may further contain pH modifiers.

[0231] The homogenized plant material may further contain fibers to alter the mechanical properties of the homogenized plant material, wherein the fibers are included in the homogenized plant material during the manufacturing process described herein. Suitable exogenous fibers for inclusion in the homogenized plant material are known in the art and include, but are not limited to, cellulose fibers, soft wood fibers, hard wood fibers, jute fibers, and combinations thereof, including fibers formed from non-tobacco and non-ginger materials. Exogenous fibers derived from tobacco and / or ginger may also be added. Any fibers added to the homogenized plant material are not considered to form part of the “particulate plant material” as defined above.

[0232] The fibers are preferably present in an amount of about 2% to about 15% by weight, most preferably about 4% by weight, based on the dry weight of the substrate.

[0233] The aerosol-forming substrate may contain one or more aerosol-forming bodies. Preferably, the aerosol-forming substrate contains a homogenized plant material containing one or more aerosol-forming bodies. As volatilization occurs, the aerosol-forming bodies can carry other vaporized compounds released from the aerosol-forming substrate upon heating, such as nicotine and flavoring agents in the aerosol. Suitable aerosol-forming bodies to be included in the aerosol-forming substrate 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 dodecanedioic acid and dimethyl tetradecanedioic acid).

[0234] The aerosol-forming substrate may have an aerosol-forming content of approximately 5% to 30% by weight, or approximately 10% to 25% by weight, or approximately 15% to 20% by weight, on a dry weight basis.

[0235] For example, when intended for use in an aerosol generating article for an electrically operated aerosol generating system having a substrate that has a heating element, it is preferable that the aerosol-forming material content be about 5% to about 30% by weight on a dry weight basis. When intended for use in an aerosol generating article for an electrically operated aerosol generating system having a substrate that has a heating element, the aerosol-forming material is preferably glycerol.

[0236] The aerosol-forming substrate may have an aerosol-forming content of about 1% to about 5% by weight on a dry weight basis. For example, if the substrate is intended for use in an aerosol-generating article in which the aerosol-forming material is kept in a storage compartment separated from the substrate, the substrate may have an aerosol-forming content greater than 1% and less than about 5%. In such embodiments, the aerosol-forming material volatilizes upon heating, and the flow of the aerosol-forming material comes into contact with the aerosol-forming substrate to incorporate flavor from the aerosol-forming substrate into the aerosol.

[0237] The aerosol-forming substrate may have an aerosol-forming content of about 30% to about 45% by weight. This relatively high level of aerosol-forming content is particularly suitable for aerosol-forming substrates intended to be heated at temperatures below 275 degrees Celsius. In this case, the homogenized plant material preferably further comprises about 2% to about 10% by weight of cellulose ether and about 5% to about 50% by weight of additional cellulose, on a dry weight basis. The use of a combination of cellulose ether and additional cellulose has been found to provide particularly effective aerosol delivery when used in aerosol-forming substrates having an aerosol-forming content of 30% to 45% by weight.

[0238] Suitable cellulose ethers include, but are not limited to, methylcellulose, hydroxypropylmethylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, ethylhydroxyethylcellulose, and carboxymethylcellulose (CMC). In a particularly preferred embodiment, the cellulose ether is carboxymethylcellulose.

[0239] As used herein, the term “additional cellulose” encompasses any cellulose material incorporated into the homogenized plant material, which is not derived from the non-tobacco plant particles or tobacco particles provided to the homogenized plant material. Thus, additional cellulose is incorporated into the homogenized plant material as an individual and distinct source of cellulose to any cellulose essentially provided within the non-tobacco plant particles or tobacco particles, in addition to the non-tobacco plant material or tobacco material. The additional cellulose is typically derived from a plant different from the non-tobacco plant particles or tobacco particles. Preferably, the additional cellulose is in the form of an inert cellulose material, which is sensorily inert and therefore does not substantially affect the functional properties of the aerosol generated from the aerosol-forming substrate. For example, the additional cellulose is preferably a tasteless and odorless material.

[0240] The additional cellulose may include cellulose powder, cellulose fibers, or a combination thereof.

[0241] The aerosol-forming material can act as a wetting agent in the aerosol-forming substrate.

[0242] The aerosol generating article may include a mouthpiece element. The mouthpiece element may extend fully to the oral end of the aerosol generating article.

[0243] The mouthpiece element may be located downstream of the hollow tubular element. If the mouthpiece element is located downstream of the hollow tubular element, it may extend all the way to the downstream end of the hollow tubular element. The mouthpiece element may be located immediately downstream of the hollow tubular element. For example, the mouthpiece element may abut against the downstream end of the hollow tubular element.

[0244] The mouthpiece element is preferably located at the downstream or oral end of the aerosol-generating article. The mouthpiece element preferably includes at least one mouthpiece filter segment for filtering aerosols generated from the aerosol-forming substrate. For example, the mouthpiece element may comprise one or more segments of fibrous filter material. Suitable fibrous filter materials are known to those skilled in the art. At least one mouthpiece filter segment is particularly preferably a cellulose acetate filter segment formed from cellulose acetate tow.

[0245] The mouthpiece element may include an oral end cavity. The oral end cavity may be defined by a hollow tubular element provided at the downstream end of the mouthpiece. Alternatively, the oral end cavity may be defined by an outer wrapper of the aerosol-generating article at the oral end.

[0246] The mouthpiece element may optionally contain flavoring agents that can be provided in any preferred form. For example, the mouthpiece element may contain one or more capsules, flavoring agent beads or granules, or one or more flavoring threads or filaments.

[0247] Preferably, the mouthpiece element has a low particle filtration efficiency.

[0248] Preferably, the mouthpiece element is formed from segments of fibrous filter material.

[0249] The mouthpiece element is preferably surrounded by a plug wrap.

[0250] The mouthpiece element is preferably connected by a tip wrapper to one or more adjacent upstream components of the aerosol-generating article.

[0251] Preferably, the mouthpiece element has an RTD of less than about 25 mmH2O. More preferably, the mouthpiece element has an RTD of less than about 20 mmH2O. Even more preferably, the mouthpiece element has an RTD of less than about 15 mmH2O.

[0252] A RTD value of approximately 10 mmH2O to approximately 15 mmH2O is particularly preferable, as it is expected that a mouthpiece element having one such RTD will contribute minimally to the overall RTD of the aerosol-generating article and therefore will not substantially filter the aerosol delivered to the consumer.

[0253] The mouthpiece element preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article. The mouthpiece element may have an outer diameter of about 5 mm to about 10 mm, or about 6 mm to about 8 mm. Preferably, the mouthpiece element has an outer diameter of about 7.2 mm.

[0254] The mouthpiece element may have a length of at least about 10 millimeters, more preferably at least about 11 millimeters, and more preferably at least about 12 millimeters. The mouthpiece element may have a length of less than about 25 millimeters, more preferably less than about 20 millimeters, and more preferably less than about 15 millimeters.

[0255] The mouthpiece element may have a length of about 10 mm to about 25 mm, more preferably about 10 mm to about 20 mm, and even more preferably about 10 mm to about 15 mm. The mouthpiece element may have a length of about 11 mm to about 25 mm, more preferably about 11 mm to about 20 mm, and even more preferably about 11 mm to about 15 mm. The mouthpiece element may have a length of about 12 mm to about 25 mm, more preferably about 12 mm to about 20 mm, and even more preferably about 12 mm to about 20 mm.

[0256] Preferably, the mouthpiece element has a length of about 12 millimeters.

[0257] Providing a relatively long mouthpiece element in an aerosol-generating article may allow for the inclusion of a capsule, or make the article more rigid at the point where the user applies their lips, or both.

[0258] The aerosol-generating article may have a total length of about 20 mm or more, preferably about 30 mm or more, and more preferably about 40 mm or more.

[0259] The aerosol-generating article may have a total length of about 100 mm or less, preferably about 80 mm or less, and more preferably about 60 mm or less.

[0260] The aerosol-generating article may have an overall length of about 20 mm to about 100 mm, preferably about 30 mm to about 80 mm, and more preferably about 40 mm to about 60 mm.

[0261] The aerosol-generating article may have a total length of approximately 45 millimeters.

[0262] The aerosol-generating article may have ventilation zones located along the hollow tubular elements.

[0263] The hollow tubular element of the present invention may include ventilation zones positioned along the length of the hollow tubular element. The features of the ventilation zones are described below with respect to aerosol-generating articles. However, it will also be understood that these can be applied directly to the hollow tubular element itself.

[0264] The ventilation zone may be located approximately 5 to 15 millimeters from the folded end portion of the hollow tubular element. The ventilation zone may also be located at least 2 millimeters from the upstream end of the hollow tubular element, more preferably at least 3 millimeters from the upstream end of the hollow tubular element, and even more preferably at least 5 millimeters from the upstream end of the hollow tubular element.

[0265] The ventilation zone may be located less than 20 millimeters from the upstream end of the hollow tubular element, more preferably less than 15 millimeters from the upstream end of the hollow tubular element, and even more preferably less than 10 millimeters from the upstream end of the hollow tubular element.

[0266] The ventilation zone may be located about 1 mm to about 10 mm from the downstream end of the hollow tubular element, more preferably about 2 mm to about 8 mm from the downstream end of the hollow tubular element, and even more preferably about 3 mm to about 6 mm from the downstream end of the hollow tubular element.

[0267] The ventilation zone may be located at least 1 millimeter from the downstream end of the hollow tubular element, more preferably at least 2 millimeters from the downstream end of the hollow tubular element, and even more preferably at least 3 millimeters from the downstream end of the hollow tubular element.

[0268] The ventilation zone may be located less than 10 millimeters from the downstream end of the hollow tubular element, more preferably less than 8 millimeters from the downstream end of the hollow tubular element, and even more preferably less than 6 millimeters from the downstream end of the hollow tubular element.

[0269] The ventilation zone may include a plurality of perforations passing through the peripheral wall of the ventilation element, which may be a hollow tubular element. Preferably, the ventilation zone includes at least one row of perforations around the periphery. The ventilation zone may also include two rows of perforations around the periphery. For example, the perforations may be formed online during the manufacture of the aerosol-generating article. Preferably, each peripheral row of perforations includes 8 to 30 perforations.

[0270] The aerosol-generating article according to the present invention may have a ventilation level of at least about 5 percent.

[0271] The term "ventilation level" is used throughout this specification to mean the volume ratio of the airflow entering the aerosol-generating article through the ventilation zone (ventilation airflow) to the sum of the aerosol airflow and the ventilation airflow. A higher ventilation level results in greater dilution of the aerosol flow delivered to the consumer.

[0272] Aerosol-generating articles may typically have a ventilation level of at least about 10 percent, preferably at least about 15 percent, and more preferably at least about 20 percent.

[0273] In a preferred embodiment, the aerosol-generating article has an air permeability level of at least about 25 percent. Preferably, the aerosol-generating article has an air permeability level of less than about 60 percent. The aerosol-generating article may have an air permeability level of about 45 percent or less. More preferably, the aerosol-generating article may have an air permeability level of about 40 percent or less, and even more preferably, about 35 percent or less.

[0274] In a particularly preferred embodiment, the aerosol-generating article has an air permeability level of about 30 percent. The aerosol-generating article may have an air permeability level of about 20% to about 60%, preferably about 20% to about 45%, more preferably about 20% to about 40%. The aerosol-generating article may have an air permeability level of about 25% to about 60%, preferably about 25% to about 45%, more preferably about 25% to about 40%. In a further embodiment, the aerosol-generating article has an air permeability level of about 30 percent to about 60 percent, preferably about 30 percent to about 45%, more preferably about 30 percent to about 40 percent.

[0275] In some preferred embodiments, the aerosol-generating article has a permeability level of about 28 percent to about 42 percent. In some particularly preferred embodiments, the aerosol-generating article has a permeability level of about 30 percent.

[0276] Embodiments in which aerosol generation comprises a hollow tubular element downstream of an aerosol generating substrate with a ventilation zone provided along the first hollow tubular element may offer several advantages. For example, though we do not wish to be bound by theory, the inventors have found that the temperature reduction resulting from introducing colder outside air into the first hollow tubular element through the ventilation zone may have a favorable effect on the nucleation and growth of aerosol particles.

[0277] The formation of aerosols from gaseous mixtures containing various chemical species depends on the delicate interactions between nucleation, evaporation, condensation, and even fusion, which explain changes in vapor concentration, temperature, and velocity fields. So-called classical nucleation theory is based on the assumption that some molecules in the gas phase are large enough to remain coherent for a long time with a sufficient probability (e.g., a 50 / 50 probability). These molecules represent a kind of critical threshold molecular cluster in transient molecular aggregates, meaning that smaller molecular clusters generally decompose into the gas phase somewhat more readily, while larger clusters generally grow more readily. These critical clusters are identified as the main nucleation cores from which droplets are expected to grow due to the condensation of molecules from the vapor. The newly nucleated, untreated droplet is assumed to emerge with a certain intrinsic diameter and then grow by several orders of magnitude. This can be facilitated and enhanced by the rapid cooling of the surrounding vapor, which induces condensation. In this regard, it is helpful to keep in mind that evaporation and condensation are two aspects of the same mechanism: the transfer of mass between liquid and gas. Evaporation involves net mass transfer from the liquid droplet phase to the gas phase, while condensation is net mass transfer from the gas phase to the liquid droplet phase. Due to evaporation (or condensation), the liquid droplet shrinks (or grows), but the number of droplets does not change.

[0278] In this scenario (and if the scenario is further complicated by fusion phenomena), the temperature and rate of cooling may play a crucial role in determining how the system responds. Generally, because the nucleation process is typically nonlinear, different cooling rates may lead to significantly different temperature behavior with respect to liquid phase (droplet) formation. While we do not wish to be bound by theory, we assume that cooling can cause a rapid increase in the number of droplet condensations, followed by a short, strong increase in this growth (nucleation burst). This nucleation burst is likely to be more pronounced at lower temperatures. Furthermore, faster cooling rates may favor the early initiation of nucleation. In contrast, a decrease in the cooling rate is likely to have a favorable effect on the final size that the aerosol droplets eventually reach.

[0279] Therefore, the rapid cooling induced by introducing outside air into the hollow tubular element through the ventilation zone can be used to favorably nucleate and grow aerosol droplets. However, at the same time, introducing outside air into the first hollow tubular element has the direct disadvantage of diluting the aerosol flow delivered to the consumer.

[0280] The inventors were surprised to find that the dilution effect on aerosols (which can be evaluated by measuring its effect on the delivery of aerosol-forming substances (such as glycerol) contained in the aerosol-generating substrate) is favorably minimized at permeability levels within the aforementioned range. In particular, permeability levels of 25 to 50 percent, and more preferably 28 to 42 percent, were found to lead to particularly satisfactory values ​​of glycerol delivery. At the same time, the degree of nucleation is enhanced, and consequently, the delivery of nicotine and aerosol-forming substances (e.g., glycerol) is enhanced.

[0281] The inventors have surprisingly found that the desirable effect of enhanced nucleation, facilitated by rapid cooling induced by the introduction of aeration air into the article, significantly outweighs the undesirable effect of dilution. Thus, satisfactory values ​​of aerosol delivery can be consistently achieved by aerosol-generating articles in accordance with this disclosure.

[0282] This is particularly advantageous for “short” aerosol-generating articles, such as when the length of the first element containing the aerosol-generating substrate is less than about 40 millimeters, preferably less than 25 millimeters, and even more preferably less than 20 millimeters, or when the total 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. As is understood, in such aerosol-generating articles, there is little time and space for aerosol formation and little time and space for the particulate phase of the aerosol to become available for delivery to the consumer.

[0283] Furthermore, since the vented hollow tubular elements can be configured so as not to substantially contribute to the overall RTD of the aerosol-generating article, the overall RTD of such an article can be advantageously fine-tuned by adjusting the length and density of the first element containing the aerosol-generating substrate, or the length, optionally length and density, of the segments of the filter material forming part of the mouthpiece, or the length and density of the segments of the element provided upstream of the first element containing the aerosol-generating substrate. Thus, aerosol-generating articles with a given RTD can be manufactured consistently and with high precision, thereby providing consumers with a satisfactory level of RTD, even in the presence of venting.

[0284] Furthermore, the inventors found that mixing the hot air from the aerosol generating substrate with fresh air from the vents drawn through the vents can be particularly facilitated when the support element does not divide the inner region of the hollow tubular element into a number of separate channels. In particular, it may be preferable to configure the support element such that the hollow inner region of the hollow tubular element consists of a single channel of the type shown, for example, in Figures 4a, 6, and 8 of the attached drawings. With such an arrangement, the fresh air drawn through a row of vents extending around the periphery of the hollow tubular element can be substantially drawn into a single channel in the hollow inner region of the hollow tubular element. This can provide improved mixing of the fresh air from the vents and the hot air from the aerosol generating substrate.

[0285] Furthermore, it may be preferable to configure the hollow tubular element such that substantially all of the hot air drawn from the aerosol generating substrate and through the section of the aerosol generating article comprising the hollow tubular element must pass through the hollow inner region of the hollow tubular element. This can be achieved by ensuring that there is no substantial gap around the outside of the hollow tubular element through which air can pass. For example, it may be preferable to configure the hollow tubular element such that its curved outer surface is substantially continuous around the periphery of the hollow tubular element, as shown, for example, in any of Figures 6, 9, and 13 to 20 of the attached drawings. Such an arrangement allows fresh air drawn through a row of vents extending around the periphery of the hollow tubular element to be drawn substantially into a single channel within the hollow inner region of the hollow tubular element. This can provide improved mixing of fresh air from the vents and hot air from the aerosol generating substrate. This can also avoid scenarios where the vents need to extend through one or more walls of the support element. Such configurations may be difficult to manufacture. Such configurations may not allow for efficient passage of ventilation air into the hollow tubular element, for example, due to the orientation of one or more walls.

[0286] The hollow tubular element and one or more support elements are preferably configured such that the hollow inner region of the hollow tubular support element consists of three or fewer channels, more preferably two or fewer channels, and even more preferably a single channel. Such an arrangement is particularly preferred when the aerosol generating article has one or more of the above-described ventilation characteristics.

[0287] The disclosure also relates to a method for forming a hollow tubular element for an aerosol-generating article. The method may include providing an apparatus for forming a hollow tubular element. The apparatus may comprise a device. The device may have an inner surface. The inner surface may define a channel in the device. The channel may extend from an upstream opening in the device. The channel may extend to a downstream opening in the device. The device may include an internal projection that protrudes into the channel. The method may also include providing a hollow tube. The method may further include passing the hollow tube through an upstream opening in the device into a channel. The method may further include passing the tube along the channel and in contact with the internal projection of the device such that the tube is folded by the internal projection to form a hollow tubular element having a support element.

[0288] According to the present invention, the method includes providing an apparatus for forming a hollow tubular element. The apparatus comprises a device. The device has an inner surface defining a channel. The channel extends from an upstream opening of the device to a downstream opening of the device. The device comprises an internal projection that protrudes into the channel. The method also includes providing a hollow tube. The method further includes passing the hollow tube through the upstream opening of the device into the channel, and passing the tube along the channel and in contact with the internal projection of the device such that the tube is folded by the internal projection to form a hollow tubular element having a support element.

[0289] The method may also involve passing a hollow tubular element out of the channel through a downstream opening of the device.

[0290] The hollow tube may be formed from a sheet. The method may include forming a hollow tube from a sheet. Forming a hollow tube from a sheet may include forming a seam by overlapping a portion of the sheet at a first end of the sheet with a portion of the sheet at an opposite second end of the sheet. Forming a seam may include attaching the portion of the sheet at the first end of the sheet to the portion of the sheet at the second end of the sheet with an adhesive. The seam may extend along the length of the hollow tube.

[0291] The diameter of the hollow tube may be substantially the same as the circumference of the hollow tubular element.

[0292] The channel may have a substantially circular cross-section. The channel may include a substantially cylindrical section. The channel may include a substantially frustoconical section.

[0293] The internal projection may have a substantially constant cross-section along the entire length of the internal projection. The internal projection may have a cross-section that varies along the length of the internal projection. For example, the internal projection may be tapered. For example, the internal projection may taper off at an upstream end of the internal projection. The length of the internal projection may extend in a direction in which the hollow tube passes through the device.

[0294] The internal projection may have a substantially rectangular cross-section in one or both of the longitudinal direction and the transverse direction. The internal projection may have a substantially triangular cross-section in one or both of the longitudinal direction and the transverse direction. Preferably, the internal projection has a triangular cross-section in the transverse direction. The triangular cross-section in the transverse direction may assist in folding the hollow tube to form the hollow tubular element and avoid tearing through the hollow tube. The internal projection may be substantially pyramidal.

[0295] When the internal projection is substantially pyramidal, the internal projection may have a maximum transverse cross-sectional area at the apex of the internal projection.

[0296] When the internal protrusion has a substantially triangular cross-section in the transverse direction, for example, when the internal protrusion is substantially pyramidal, the internal protrusion may comprise a first edge. The first edge may be adjacent to a portion of the inner surface of the device that defines the channel. The internal protrusion may comprise a second edge. The second edge may be adjacent to a portion of the inner surface of the device that defines the channel. The second edge may extend from the upstream end of the internal protrusion. The internal protrusion may comprise a third edge. The third edge may be located within the channel. The third edge may extend from the upstream end of the internal protrusion. The third edge may extend to the apex of the internal protrusion. The third edge may define the tip of the internal protrusion.

[0297] The hollow tube may have a perimeter substantially equal to the inner perimeter of the transverse cross-section of the device at the apex of the internal protrusion.

[0298] The internal protrusion may be a first internal protrusion, and the device may comprise one or more additional internal protrusions. The device may comprise two to six internal protrusions. Preferably, the device comprises three internal protrusions. Each of the internal protrusions may be identical to one another. One of the internal protrusions may be different from another internal protrusion. The internal protrusions may be evenly spaced around the channel.

[0299] The internal shape of the device may be configured to achieve a slip fit between the hollow tube and the inner surface of the device that defines the channel. This may be particularly desirable in that the hollow tube is in contact with one or more internal protrusions. This may help to fold the hollow tube at a desired position to form a hollow tubular element.

[0300] The apparatus may comprise a first section. The first section of the apparatus may include at least a portion of the apparatus's channel. The channel may have a substantially constant cross-section along the entire length of the first section of the apparatus. For example, a portion of the channel extending through the first section of the apparatus may be substantially cylindrical. The cross-section of the channel may vary along the length of the first section of the apparatus. For example, the cross-sectional area of ​​the channel at the upstream end of the first section of the apparatus may be larger than the cross-sectional area of ​​the channel at the downstream end of the first section of the apparatus. Preferably, a portion of the channel extending through the first section of the apparatus is substantially frustoconical. In this case, preferably, the diameter of the channel at the upstream end of the first section is larger than the diameter of the channel at the downstream end of the first section. The diameter of the channel at a point along the first section, for example, at the upstream end of the first section, may be approximately the same as the diameter of a hollow tube. For example, the diameter of the channel at a point along the first section at the downstream end of the first section may be approximately the same as the diameter of a hollow tubular element. The channel diameter may be selected such that the outer surface of the hollow tube remains in contact with the inner surface of the apparatus during the process of passing the hollow tube through the first section of the apparatus to assist in shaping the hollow tube into a hollow tubular element.

[0301] The internal projection may be part of a first section of the device. That is, the first section of the device may include an internal projection that protrudes into a channel. The internal projection may extend from the upstream end of the first section of the device to the downstream end of the first section of the device. Thus, the internal projection may extend along the entire length of the first section of the device. The internal projection may project into a portion of a channel that extends through the first section of the device. If the internal projection is tapered, it may taper off at the upstream end of the first section of the device. Furthermore, if the internal projection includes a first edge, the first edge may extend from the upstream end of the first section of the device. If the internal projection includes an edge of the section, the second edge may extend from the upstream end of the first section of the device. If the internal projection includes a third edge, the third edge may extend from the upstream end of the first section of the device. The third edge may be located within the channel.

[0302] The first section of the apparatus may extend from the upstream opening to the downstream opening. In this case, the first section of the apparatus may be the only section of the apparatus. That is, the apparatus may consist of only the first section of the apparatus.

[0303] In addition to the first section, the apparatus may comprise one or more additional sections.

[0304] For example, the apparatus may include a second section. The second section of the apparatus may include at least a portion of the apparatus's channel. The second section may extend from the upstream opening of the apparatus. The second section may extend to the first section of the apparatus. In other words, the second section may be adjacent to and upstream of the first section of the apparatus.

[0305] A portion of the channel extending through the second section may have a substantially circular cross-section. Preferably, the portion of the channel extending through the second section has a substantially circular cross-section at the downstream end of the second section. In this case, preferably, the diameter of the channel at the downstream end of the second section is approximately the same as the diameter of the channel at the upstream end of the first section.

[0306] The channel may have a larger cross-sectional area at the upstream end of the second section than at the downstream end of the second section. A portion of the channel extending through the second section may be substantially frustoconical.

[0307] A portion of the channel extending through the second section may have a substantially constant cross-section along the entire length of the second section. A portion of the channel extending through the second section may be substantially cylindrical.

[0308] The device may include a third section. The third section of the device may include at least a portion of the device's channel. The third section may extend from the downstream end of the first section of the device. The third section may extend to the downstream opening of the device. In other words, the third section may be adjacent to and downstream of the first section of the device.

[0309] A portion of the channel extending through the third section may have a substantially circular cross-section. Preferably, the portion of the channel extending through the third section has a substantially circular cross-section at the upstream end of the third section. In this case, preferably, the diameter of the channel at the upstream end of the third section is approximately the same as the diameter of the channel at the downstream end of the first section.

[0310] The channel may have a larger cross-sectional area at the downstream end of the third section than at the upstream end of the third section. A portion of the channel extending through the third section may be substantially frustoconical.

[0311] A portion of the channel extending through the third section may have a substantially constant cross-section along the entire length of the third section. A portion of the channel extending through the third section may be substantially cylindrical.

[0312] The apparatus may comprise only a first section and a third section. Alternatively, the apparatus may comprise a first section, a second section, and a third section. In this case, the first section may be located between the second and third sections of the apparatus.

[0313] The method involves passing a hollow tube through the upstream opening of the device into the channel of the device.

[0314] The method also includes passing a hollow tube along a channel and in contact with an internal projection of the apparatus. If the apparatus has a first section that includes an internal projection, the method may include passing a hollow tube along a channel and in contact with an internal projection at the upstream end of the first section of the apparatus. The method may also include passing a hollow tube along a channel through the first section of the apparatus such that the outer surface of the hollow tube is in contact with the inner surface of the first section of the apparatus. The method may also include passing a hollow tube along a channel through the first section of the apparatus such that the outer surface of the hollow tube is in contact with an internal projection. Due to the configuration of the first section of the apparatus, passing a hollow tube along the first section of the apparatus may cause the hollow tube to deform and conform to the internal shape of the first section of the apparatus. In particular, if a portion of the channel extending through the first section is substantially frustoconical, the shape of the channel in the first section, combined with the presence of an internal projection in the first section, may help to shape the hollow tube into a form with a reduced diameter and a folded internal projection that forms a support element. As a result, by passing the hollow tube through the first section of the apparatus, the hollow tube can form a first fold at the first edge of the internal projection, a second fold at the second edge of the internal projection, and a third fold at the third edge of the internal projection. Thus, by passing the hollow tube through the first section of the apparatus, a hollow tubular element formed from a sheet can be formed, the hollow tubular element comprising a peripheral portion defining a hollow inner region and a support element, the support element being subordinate to the peripheral portion along both the first and second folds of the sheet, and the support element comprising a third fold of the sheet located within the hollow inner region.

[0315] The method may include passing a hollow tubular element out of the channel through a downstream opening of the device.

[0316] Where the device comprises a second section extending from an upstream opening of the device to an upstream end of a first section of the device, the method comprises, before passing the hollow tube through the first section of the device, passing the hollow tube through the second section of the device along the channel. Passing the hollow tube through the second section of the device can assist in inserting the hollow tube into the channel and bringing it into contact with the internal projection.

[0317] Where the device comprises a third section extending from a downstream end of the first section of the device to a downstream opening of the device, the method may comprise, after passing the hollow tube through the first section of the device, passing the hollow tube through the third section of the device along the channel. The method may comprise passing the hollow tubular element through the third section of the device and out of the channel through the downstream opening of the device. Passing the hollow tubular element through the third section of the device can also assist the hollow tubular element in exiting the device. Passing the hollow tubular element through the third section of the device can assist in maintaining a desired shape of the hollow tubular element after folding the hollow tubular element, for example, by assisting in maintaining a desired curvature of the hollow tubular element.

[0318] The method may comprise attaching a first side wall of the support element to a second side wall of the support element with an adhesive, wherein the first side wall of the support element extends from a first fold to a third fold, and the second side wall of the support element extends from a second fold to the third fold. The attaching step may be performed before the hollow tubular element exits the device. In this case, the attaching step may be performed while the hollow tubular element passes through the channel. The attaching step may be performed after the hollow tubular element exits the device.

[0319] The method may comprise wrapping a wrapper around the hollow tubular element. The wrapping step may be performed before the hollow tubular element exits the device. The wrapping step may be performed after the hollow tubular element exits the device.

[0320] The method may include, for example, attaching a wrapper to a hollow tubular element by adhesive. The step of attaching the wrapper to the hollow tubular element may be performed before the hollow tubular element leaves the apparatus. The step of attaching the wrapper to the hollow tubular element may be performed after the hollow tubular element leaves the apparatus.

[0321] Herein, embodiments of the present invention will be described in detail, albeit only as illustrative examples, with reference to the accompanying drawings. [Brief explanation of the drawing]

[0322] [Figure 1] Figure 1 shows a schematic side view of an aerosol generating article comprising a hollow tubular element according to a first embodiment of the present invention. [Figure 2] Figure 2 shows an exploded view of some of the components of the aerosol-generating article shown in Figure 1. [Figure 3] Figure 3 shows a partially transparent perspective view of the hollow tubular element of the aerosol generating article shown in Figure 1. [Figure 4] Figures 4A and 4B show cross-sectional views of the upstream end face of the hollow tubular element of the aerosol-generating article in Figure 1. Figure 4C shows a cross-sectional view of the aerosol-generating article in the hollow tubular element of Figure 1. [Figure 5] Figure 5 shows a perspective view of a hollow tubular element for an aerosol generating article according to a second embodiment of the present invention. [Figure 6] Figure 6 shows a cross-sectional view of the upstream end face of the hollow tubular element shown in Figure 5. [Figure 7] Figure 7 shows a cross-sectional view of the upstream end face of a hollow tubular element for an aerosol generating article according to a third embodiment of the present invention. [Figure 8] Figure 8 shows a cross-sectional view of the upstream end face of a hollow tubular element for an aerosol generating article according to a fourth embodiment of the present invention. [Figure 9] Figure 9 shows a cross-sectional view of the upstream end face of a hollow tubular element for an aerosol generating article according to the fifth embodiment of the present invention. [Figure 10]Figure 10 shows a side view of an apparatus for forming a hollow tubular element for an aerosol generating article according to a first embodiment of the present invention. [Figure 11] Figure 11A shows a cross-sectional view of the equipment in Figure 10 taken along the plane A to A in Figure 10. Figure 11B shows a cross-sectional view of the equipment in Figure 10 taken along the plane B to B in Figure 10. [Figure 12] Figure 12A shows a cross-sectional view of a hollow tube used, for example, to form a hollow tubular element for an aerosol generating article according to a first embodiment of the present invention. Figure 12B shows a cross-sectional view of a hollow tubular element for an aerosol generating article formed from the hollow tube of Figure 12A and using the apparatus of Figure 10. [Modes for carrying out the invention]

[0323] Features described in reference to one embodiment or example may also be applicable to other embodiments and examples.

[0324] A non-exclusive list of non-limiting embodiments is provided below. Any one or more features of these embodiments may be combined with any one or more features of other embodiments or models described herein.

[0325] Example 1. A hollow tubular element for an aerosol generating article, wherein the hollow tubular element includes a peripheral portion that provides a curved outer surface of the hollow tubular element and defines a hollow inner region of the hollow tubular element, and an internal projection extending into the hollow tubular element, wherein the hollow tubular element is formed from a sheet, the sheet including a first portion and a second portion adjacent to the first portion with a first fold in between, the first portion of the sheet forming at least a portion of the peripheral portion of the hollow tubular element, the entire first portion of the sheet forming at least a portion of the curved outer surface of the hollow tubular element, and the second portion of the sheet defining an internal projection of the hollow tubular element, the internal projection extending from the first fold into the hollow inner region of the hollow tubular element. Example 2. A hollow tubular element according to any one of the examples in Example 1, wherein the peripheral portion is formed from a sheet. Example 3. A hollow tubular element according to Example 2, in which the peripheral portion and support elements are integrally formed from a sheet. Example 4. A hollow tubular element according to Example 3, wherein the peripheral portion and support elements are formed from separate sheets. Example 5. A hollow tubular element according to any one of Examples 1 to 4, wherein the peripheral portion includes a tube. Example 6. A hollow tubular element according to any one of Examples 1 to 5, wherein the support element extends along approximately 10 percent to approximately 100 percent of the length of the hollow tubular element. Example 7. A hollow tubular element according to any one of Examples 1 to 6, wherein the first point of the peripheral portion and the second point of the peripheral portion are spaced apart from each other. Example 8. A hollow tubular element according to Embodiment 7, wherein the first point of the peripheral portion and the second point of the peripheral portion are substantially opposite each other in a vertical direction. Example 9. A hollow tubular element according to any one of Examples 1 to 6, wherein the first point of the peripheral portion and the second point of the peripheral portion are adjacent to each other. Example 10. A hollow tubular element according to Embodiment 9, wherein a first point on the peripheral portion and a second point on the peripheral portion are in contact with each other. Example 11. A hollow tubular element according to any one of Examples 1 to 10, wherein the support element includes a tip, and the tip is located within a hollow inner region. Example 12. A hollow tubular element according to Example 11, in which the tip of the support element is spaced apart from the surrounding portion. Example 13. A hollow tubular element according to any one of the embodiments of 11, wherein the tip of the support element is located at a point adjacent to a point in the peripheral portion. Example 14. A hollow tubular element according to any one of Examples 1 to 13, wherein the surface of the support element along the long axis is substantially planar. Example 15. A hollow tubular element according to Example 14, wherein a substantially planar surface extends from a first point of the peripheral portion. Example 16. A hollow tubular element according to any one of Examples 14-15, wherein the substantially planar surface extends to a second point in the peripheral portion. Example 17. A hollow tubular element according to any one of Examples 1 to 16, wherein the support element includes a substantially straight portion when viewed from the upstream end of the hollow tubular element. Example 18. A hollow tubular element according to Embodiment 17, wherein the substantially straight portion extends from a first point on the peripheral portion when viewed from the upstream end of the hollow tubular element. Example 19. A hollow tubular element according to any one of Examples 17 to 18, wherein the substantially straight portion extends to a second point on the peripheral portion when viewed from the upstream end of the hollow tubular element. Example 20. A hollow tubular element according to any one of Examples 1 to 19, wherein the support element relies on the peripheral portion along a first fold of the sheet, and the first fold is located at a first point in the peripheral portion. Example 21. A hollow tubular element according to Example 20, wherein the first fold extends along a portion of the length of the hollow tubular element. Example 22. A hollow tubular element according to Example 21, wherein the first fold extends substantially along the entire length of the hollow tubular element. Example 23. A hollow tubular element according to any one of Examples 20-22, wherein the first fold is parallel to the longitudinal axis of the hollow tubular element. Example 24. A hollow tubular element according to any one of Examples 20-22, wherein the first fold is non-parallel to the longitudinal axis of the hollow tubular element. Example 25. A hollow tubular element according to any one of Examples 20-24, wherein the first fold is the only fold along which the support element is subordinate to the peripheral portion. Example 26. A hollow tubular element according to any one of Examples 20 to 24, wherein the support element is subordinate to the peripheral portion along a second fold of the sheet, and the second fold is located at a second point of the peripheral portion. Example 27. A hollow tubular element according to Example 26, wherein the second fold extends along a portion of the length of the hollow tubular element. Example 28. A hollow tubular element according to Example 27, wherein the second fold extends substantially along the entire length of the hollow tubular element. Example 29. A hollow tubular element according to any one of Examples 26-28, wherein the second fold is parallel to the longitudinal axis of the hollow tubular element. Example 30. A hollow tubular element according to any one of Examples 26-28, wherein the first fold is non-parallel to the longitudinal axis of the hollow tubular element. Example 31. A hollow tubular element according to any one of Examples 26-30, wherein the first fold and the second fold are parallel to each other. Example 32. A hollow tubular element according to any one of Examples 26-30, wherein the first fold and the second fold are non-parallel to each other. Example 33. A hollow tubular element according to any one of Examples 26-32, wherein the support element includes a third fold in the sheet. Example 34. A hollow tubular element according to claim 33, wherein a third fold defines the tip of the support element, and the tip is positioned within a hollow inner region. Example 35. A hollow tubular element according to any one of Examples 33 to 34, wherein the third fold of the sheet is located approximately equidistant from the first fold and the second fold of the sheet. Example 36. A hollow tubular element according to any one of Examples 33 to 35, wherein the first fold and the third fold define the first side wall of the support element. Example 37. A hollow tubular element according to Embodiment 36, wherein the first side wall of the support element is substantially straight. Example 38. A hollow tubular element according to any one of Examples 36-37, wherein the second and third folds define the second side wall of the support element. Example 39. A hollow tubular element according to Example 38, wherein the second side wall of the support element is substantially straight. Example 40. A hollow tubular element according to any one of Examples 38 to 39, wherein the surface of the first side wall and the surface of the second side wall are in contact with each other. Example 41. A hollow tubular element according to Embodiment 39, wherein both the first and second side walls are substantially straight, and the first and second side walls define an angle of about 5 degrees or more between them. Example 42. A hollow tubular element according to any one of Examples 1 to 41, wherein the support element has a substantially triangular cross-section. Example 43. A hollow tubular element according to any one of Examples 38-40, wherein both the first and second side walls are substantially straight, and the angle formed between the first and second side walls is approximately 0 degrees. Example 44. A hollow tubular element according to any one of Examples 1 to 40, wherein the cross-section of the support element includes a curved portion. Example 45. A hollow tubular element according to any one of Examples 1-40 and 44, wherein the support element includes multiple peaks and troughs when viewed from the upstream end of the hollow tubular element. Example 46. A hollow tubular element according to any one of Examples 1-40, 44, and 45, wherein the support element has a corrugated profile when viewed from the upstream end of the hollow tubular element. Example 47. A hollow tubular element according to Embodiment 46, wherein the support element is substantially sinusoidal when viewed from the upstream end of the hollow tubular element. Example 48. A hollow tubular element according to Example 46, wherein the support element has a substantially triangular corrugated profile when viewed from the upstream end of the hollow tubular element. Example 49. A hollow tubular element according to any one of Examples 44, 46, and 47, wherein the cross-section of the support element is substantially S-shaped. Example 50. A hollow tubular element according to Example 44, wherein the cross-section of the support element is substantially omega-shaped. Example 51. A hollow tubular element according to Example 44, wherein the cross-section of the support element is substantially C-shaped. Example 52. A hollow tubular element according to any one of Examples 45, 46, and 48, wherein the support element is substantially W-shaped when viewed from the upstream end of the hollow tubular element. Example 53. A hollow tubular element according to any one of Examples 1 to 52, wherein the hollow tubular element includes at least one symmetrical plane in the direction of the long axis. Example 54. A hollow tubular element according to any one of Examples 1 to 53, wherein the hollow tubular element is radially symmetrical. Example 55. A hollow tubular element according to any one of Examples 1 to 54, wherein the cross-sectional area of ​​the hollow tubular element is substantially constant along the entire length of the hollow tubular element. Example 56. A hollow tubular element according to any one of Examples 1 to 55, wherein the hollow tubular element has a substantially constant cross-section along the entire length of the hollow tubular element. Example 57. A hollow tubular element according to any one of Examples 1 to 56, wherein the support element divides the hollow inner region into multiple channels. Example 58. A hollow tubular element according to Example 57, in which a support element divides the hollow inner region into two to four channels. Example 59. A hollow tubular element according to any one of Examples 1 to 58, wherein a support element penetrates the radial center of the hollow tubular element. Example 60. A hollow tubular element according to any one of Examples 1 to 59, wherein the support element is spaced from the radial center of the hollow tubular element at a distance of approximately 5 percent to approximately 90 percent of the radius of the hollow tubular element. Example 61. A hollow tubular element according to any one of Examples 1 to 60, wherein the support element is spaced approximately 0.2 mm to 3 mm away from the radial center of the hollow tubular element. Example 62. A hollow tubular element according to any one of Examples 1 to 61, wherein the support element includes a tip and the support element has a depth of approximately 0.6 mm to approximately 3 mm. Example 63. A hollow tubular element according to any one of Examples 1 to 62, wherein the support element is the sole support element for the hollow tubular element. Example 64. A hollow tubular element according to any one of Examples 1 to 62, wherein the hollow tubular element includes multiple support elements. Example 65. A hollow tubular element according to Example 64, comprising two to six support elements. Example 66. A hollow tubular element according to Example 65, comprising three support elements. Example 67. A hollow tubular element according to any one of Examples 64 to 66, wherein each of the support elements is identical to one another. Example 68. A hollow tubular element according to any one of Examples 64 to 67, wherein each of the support elements is spaced almost evenly around the peripheral portion of the hollow tubular element. Example 69. A hollow tubular element having a length of approximately 10 mm to approximately 30 mm, according to any one of Examples 1 to 68. Example 70. A hollow tubular element having an outer diameter of approximately 5 mm to approximately 12 mm, according to any one of Examples 1 to 69. Example 71. A hollow tubular element having an outer diameter of approximately 4.5 mm to approximately 11.5 mm, according to any one of Examples 1 to 70. Example 72. A hollow tubular element according to any one of Examples 1 to 71, wherein the hollow tubular element has a total internal surface area of ​​approximately 25 square millimeters per millimeter length to approximately 70 square millimeters per millimeter length. Example 73. A hollow tubular element according to any one of Examples 1 to 72, which provides a negligible level of draw resistance. Example 74. A hollow tubular element according to any one of Examples 1 to 73, wherein the hollow tubular element has a void ratio of approximately 90 percent or more in the longitudinal direction. Example 75. A hollow tubular element according to any one of Examples 1 to 74, wherein the sheet forming one or both of the support element and / or peripheral portion is formed from paper, any other paper-based material, any other cellulosic material, a bioplastic material, or metal. Example 76. A hollow tubular element according to Example 75, wherein the sheet forming one or both of the support element and / or the surrounding portion is formed from paper. Example 77. A hollow tubular element according to any one of Examples 1 to 76, wherein the sheet forming one or both of the peripheral portion and / or support element has a basis weight of approximately 35 grams / m² to approximately 80 grams / m². Example 78. A hollow tubular element according to any one of Examples 1 to 77, wherein the sheet forming one or both of the peripheral portion and / or support element has a thickness of approximately 100 micrometers to approximately 130 micrometers. Example 79. A hollow tubular element according to any one of Examples 1 to 78, wherein the sheet forming one or both of the support element and / or the surrounding portion is an aluminum sheet, and the sheet has a thickness of about 10 micrometers to about 20 micrometers. Example 80. A hollow tubular element according to any one of Examples 1 to 79, wherein substantially the entire support element is formed from a single layer of sheets forming the support element. Example 81. A hollow tubular element according to any one of Examples 1 to 80, wherein the peripheral portion is formed from a single sheet layer. Example 82. A hollow tubular element according to any one of Examples 1 to 80, wherein the peripheral portion is formed from multiple overlapping layers of sheets. Example 83. A hollow tubular element according to any one of Examples 1 to 80, wherein the peripheral portion is formed from multiple sheets. Example 84. A hollow tubular element according to any one of Examples 1 to 83, wherein the peripheral portion has a thickness of approximately 15 micrometers to approximately 600 micrometers. Example 85. A hollow tubular element according to Example 84, wherein the peripheral portion has a thickness of approximately 100 micrometers to approximately 130 micrometers. Example 86. A hollow tubular element according to any one of Examples 1 to 85, wherein the hollow tubular element has a total weight of approximately 150 milligrams or less. Example 87. A hollow tubular element according to any one of Examples 1 to 86, wherein the hollow tubular element has an average weight of about 10 milligrams per millimeter length of the hollow tubular element. Example 88. An aerosol generating article comprising a hollow tubular element according to any one of Examples 1 to 87, wherein the hollow tubular element is surrounded by a wrapper. Example 89. An aerosol generating article comprising a hollow tubular element according to any one of Examples 1 to 88, wherein the hollow tubular element is connected by a wrapper to one or more adjacent components of the aerosol generating article. Example 90. A hollow tubular element comprising an adhesive, according to any one of Examples 1 to 89. Example 91. A hollow tubular element according to any one of Examples 1 to 90, wherein the sheet includes a flame-retardant portion containing a flame-retardant composition. Example 92. A hollow tubular element according to Example 91, wherein the flame-retardant portion extends from the upstream end of the hollow tubular element. Example 93. A hollow tubular element according to Example 91 or 92, wherein the flame-retardant portion extends across one or both of the inner and outer surfaces of the hollow tubular element. Example 94. A hollow tubular element according to Example 93, wherein the flame-retardant portion extends over substantially the entire inner surface and / or both of the outer surface of the hollow tubular element. Example 95. An aerosol generating article comprising a hollow tubular element according to any one of Examples 1 to 94, further comprising a first element including an aerosol-forming substrate and a susceptor, wherein the susceptor is located at the downstream end of the first element. Example 96. An aerosol generating article according to Example 95, in which a susceptor is disposed within an aerosol-forming substrate. Example 97. An aerosol generating article according to Example 95 or 96, wherein a susceptor is disposed around an aerosol-forming substrate. Example 98. A hollow tubular element according to any one of Examples 1 to 97, further comprising a ventilation zone positioned along the hollow tubular element.

[0326] Figure 1 shows an aerosol generating article 1 comprising a hollow tubular element 100 according to a first embodiment of the present invention. The aerosol generating article 1 comprises a first element 10 containing an aerosol forming substrate 12, a susceptor element 20 disposed within the first element 10, a hollow tubular element 100 located downstream of the first element 10, and a mouth end element 30. Thus, the aerosol generating article extends from the upstream or distal end 2 to the downstream or mouth end 4.

[0327] The aerosol-generating article has a total length of approximately 45 millimeters.

[0328] The first element 10 is in the form of a rod containing one of the above-described types of aerosol-forming substrates 12. The structure and dimensions of the first element 10 are defined by the aerosol-forming substrate 12, which is also in the form of a rod. The first element 10 containing the aerosol-forming substrate 12 has an outer diameter of about 7.25 millimeters and a length of about 12 millimeters.

[0329] The susceptor element 20 is an elongated susceptor element 20. The susceptor element 20 is substantially longitudinally positioned within the first element 10 so as to be substantially parallel to the longitudinal direction of the first element 10. The susceptor element 20 is located at the radial center within the first element 10 and extends effectively along the entire longitudinal axis of the first element 10. In particular, the susceptor element 20 is substantially longitudinally positioned within the aerosol-forming substrate 12 and is located at the radial center with respect to the aerosol-forming substrate 12. The susceptor element 20 extends across the entire length of the aerosol-forming substrate 12 from the upstream end to the downstream end. In practice, the susceptor element 20 has substantially the same length as the first element 10 and the aerosol-forming substrate 12.

[0330] The susceptor element 20 is provided in the form of a strip, having a length of about 12 millimeters, a thickness of about 60 micrometers, and a width of about 4 millimeters.

[0331] The hollow tubular element 100 is positioned immediately downstream of the first element 10 and is longitudinally aligned with the first element 10. The upstream end of the hollow tubular element 100 abuts against the downstream end of the first element 10, in particular the downstream end of the aerosol-forming substrate 10. This advantageously prevents or limits the movement of both the first element 10 and the susceptor element 20.

[0332] The mouthpiece element 30 is positioned immediately downstream of the hollow tubular element 100, and the mouthpiece element 30 is longitudinally aligned with the hollow tubular element. The upstream end of the mouthpiece element 30 abuts against the downstream end of the hollow tubular element 100.

[0333] The mouthpiece element 30 is supplied in the form of a cylindrical plug made of low-density cellulose acetate. The mouthpiece element 30 has a length of approximately 12 mm and an outer diameter of approximately 7.25 mm. The RTD of the mouthpiece element 30 is approximately 12 mm of H2O.

[0334] The hollow tubular element 100 is best seen in the exploded perspective view of some of the components of the aerosol generating article 1 in Figure 2, and in the partially transparent perspective view of the hollow tubular element in Figure 3.

[0335] The hollow tubular element 100 is formed from a sheet, which includes a first portion and a second portion adjacent to the first portion, with a first fold 141 between them. The second portion of the sheet is adjacent to the first portion of the sheet, with the first fold 141 between them. This means that the only part between the first portion of the sheet and the second portion of the sheet is the first fold 141. In other words, there is no other part of the sheet between the first portion of the sheet and the second portion of the sheet. The second portion of the sheet is subordinate to the first portion of the sheet along the first fold.

[0336] The first portion of the sheet forms at least a portion of the peripheral portion 110 of the hollow tubular element 100, and the peripheral portion 110 defines the hollow inner region 120 of the hollow tubular element 100. The second portion of the sheet defines the support element 130 of the hollow tubular element 100, and the support element 130 extends from a first point 131 of the peripheral portion 110, across the hollow inner region 120, to a second point 132 of the peripheral portion 110.

[0337] The peripheral portion 110 and the support element 130 are integrally formed from the same sheet of paper. The sheet of paper has a basis weight of approximately 78 grams / square meter. Substantially the entire portion of the sheet forming the peripheral portion 110 forms the curved outer surface of the hollow tubular element 100.

[0338] To form the support element 130, the paper sheet includes a seam (not shown) where two layers of paper sheets overlap each other. The seam may be part of one or both of the peripheral portion 110 and the support element 130. The seam extends across a small portion of one or both of the peripheral portion 110 and the support element 130. Thus, substantially the entire peripheral portion 110 is formed from a single layer of sheets. Furthermore, substantially the entire support element 130 is formed from a single layer of sheets.

[0339] The support element 130 is subordinate to the peripheral portion 110 along a first fold 141 of the sheet, the first fold 141 is located at a first point 131 in the peripheral portion 110, and the first fold 141 extends substantially along the entire length of the hollow tubular element 100. The second portion of the sheet includes a second fold 142. The support element 130 is also subordinate to the peripheral portion 110 along a second fold 142 of the sheet, the second fold 142 is located at a second point 132 in the peripheral portion 110, and the second fold 142 extends substantially along the entire length of the hollow tubular element 100.

[0340] Therefore, the support element 130 also extends along substantially the entire length of the hollow tubular element 100. In fact, the support element 130 has substantially the same length as the hollow tubular element 100.

[0341] The hollow tubular element 100 has a length of approximately 8 millimeters.

[0342] The hollow tubular element 100 has a total weight of approximately 34 milligrams. Therefore, the hollow tubular element has an average weight of approximately 4.25 milligrams / millimeter.

[0343] The hollow tubular element 100 has a constant cross-section along its entire length.

[0344] Both the first fold 141 and the second fold 142 are parallel to the longitudinal axis of the hollow tubular element 100. Therefore, the first fold 141 and the second fold 142 are parallel to each other.

[0345] As shown in Figure 3, the support element 130 includes a third fold 143 of the sheet, the third fold 143 being parallel to the first fold 141 and the second fold 142 and equidistant from them. This helps to provide a strong support barrier to prevent or reduce the movement of the first elements 10, particularly the aerosol-forming substrate 12 and the susceptor element 20. The third fold 143 defines the tip of the support element.

[0346] Figures 4A and 4B show cross-sectional views of the upstream end face of the hollow tubular element 100.

[0347] The first fold 141 and the third fold 143 both define the first side wall 151 of the support element 130, the first side wall 151 is substantially straight, and the outer surface 153 of the first side wall 151 forms the outer surface of the hollow tubular element 100. The second fold 142 and the third fold 143 both define the second side wall 151 of the support element 130, the second side wall 152 is substantially straight, and the outer surface 154 of the second side wall 152 forms the outer surface of the hollow tubular element.

[0348] The support element 130 has a roughly triangular cross-section.

[0349] The first point 131 and the second point 132 in the peripheral portion 110 are separated from each other by a distance of approximately 1 millimeter 160. Therefore, the first fold 141 and the second fold 142 are also separated from each other by a distance of approximately 1 millimeter.

[0350] The first side wall 151 and the second side wall 152 define an angle of approximately 30 degrees between them.

[0351] The depth of the support element 130 is approximately 2 millimeters. That is, the distance between the first point 131 in the peripheral portion and the tip of the support element 130 is approximately 2 millimeters. Therefore, the distance between the first fold 141 and the third fold 143 is also approximately 2 millimeters.

[0352] The tip of the support element 130 is spaced approximately 1.5 millimeters away from the radial center 162 of the hollow tubular element 100. Therefore, the support element 130 is spaced approximately 1.5 millimeters away from the radial center 162 of the hollow tubular element.

[0353] The outer diameter 164 of the hollow tubular element is approximately 7.2 millimeters. Therefore, the support element 130 is located at a distance of approximately 42 percent of the radius of the hollow tubular element 100 from the radial center 162 of the hollow tubular element 100. Figure 4C shows the wrapper 190 surrounding the hollow tubular element 100.

[0354] The support element 130 is the first support element 130, and the hollow tubular element includes two additional support elements, the second support element 170 and the third support element 180. This is advantageous because it can provide the hollow tubular element 100 with additional strength and rigidity in both the longitudinal and transverse directions to prevent or limit the movement of the first element 110, in particular the aerosol-forming substrate 112, and the susceptor element 120, while deformation of the hollow tubular element 100 can be avoided.

[0355] Each of the support elements 130, 170, and 180 is identical to one another and is evenly spaced around the hollow tubular element 100. The area around the hollow tubular element 100 is shown by a dashed curve in Figure 4B.

[0356] Figure 5 shows a perspective view of a hollow tubular element 200 for an aerosol generating article according to a second embodiment of the present invention. The hollow tubular element 200 of the second embodiment differs from the hollow tubular element 100 of the first embodiment in that the first point 231 and the second point 232 in the peripheral portion are located closer to each other. In particular, the first point 231 and the second point 232 in the peripheral portion are separated from each other by a distance of approximately 0 millimeters. Thus, the first fold 241 and the second fold 242 are also separated from each other by a distance of approximately 0 millimeters. The depth of the support element 230 is the same as the depth of the support element 130, which is approximately 2 millimeters.

[0357] Figure 6 shows a cross-sectional view of the upstream end face of the hollow tubular element 200. The angle formed between the first side wall 251 and the second side wall 252 is approximately 0 degrees. The substantial entirety of the first side wall 251 and the substantial entirety of the second side wall 252 are in contact with each other and are attached to each other by adhesive. This can significantly increase the strength and rigidity of the hollow tubular element in both the longitudinal and transverse directions. This also avoids the need to enclose the hollow tubular element 200 in a wrapper. Thus, the weight of the hollow tubular element 200 can be minimized so that it can be assembled into the aerosol generating article 1 using an existing high-speed aerosol generating article assembly machine.

[0358] Figure 7 shows a cross-sectional view of the upstream end face of a hollow tubular element 300 for an aerosol generating article according to a third embodiment of the present invention. The hollow tubular element 300 of the third embodiment is generally the same as the hollow tubular element 100 of the first embodiment. However, the hollow tubular element 300 of the third embodiment differs from the hollow tubular element 100 of the first embodiment in that the support element 330 has a depth approximately equal to the radius of the hollow tubular element 300. Thus, the support element 330 extends to the radial center of the hollow tubular element 300. In particular, the tip of the support element 330 is located at or adjacent to the radial center of the hollow tubular element 300. Similar to the hollow tubular element 100 of the first embodiment, the hollow tubular element 300 of the third embodiment includes three identical support elements 330, 370, and 380 that are evenly spaced around the periphery of the hollow tubular element 300. Therefore, the support elements 330, 370, and 380 divide the hollow inner region into three channels. In particular, the tips of the support elements 330, 370, and 380 are adjacent to each other at the radial center of the hollow tubular element 300.

[0359] Figure 8 shows a cross-sectional view of the upstream end face of a hollow tubular element 400 for an aerosol generating article according to a fourth embodiment of the present invention. The hollow tubular element 400 is generally the same as the hollow tubular element 400 of the first embodiment, except that the first point 431 and the second point 432 in the peripheral portion are located closer to each other. In particular, the first point 431 and the second point 432 in the peripheral portion are separated from each other by a distance of about 0.8 millimeters. Furthermore, in Figure 8, the depth of the support element 430 is about 3 millimeters. Furthermore, in Figure 8, the first side wall and the second side wall define an angle of about 15 degrees between them.

[0360] Figure 9 shows a cross-sectional view of the upstream end face of a hollow tubular element 500 for an aerosol generating article according to the fifth embodiment of the present invention. The hollow tubular element 500 is generally the same as the hollow tubular element 200 of the second embodiment, except that the depth of the hollow tubular element 200 is approximately the same as the radius of the hollow tubular element 500. Thus, the support element 530 extends to the radial center of the hollow tubular element 500. In particular, the tip of the support element 530 is located at or adjacent to the radial center of the hollow tubular element 500. Similar to the hollow tubular element 100 of the first embodiment and the hollow tubular element 200 of the second embodiment, the hollow tubular element 500 of the fifth embodiment includes three identical support elements. Thus, the three support elements of the hollow tubular element 500 divide the hollow region of the hollow tubular element 500 into three channels. In particular, the tips of the support elements 530, 370, and 580 are adjacent to each other at the radial center of the hollow tubular element 300.

[0361] Figure 10 shows a method for forming a hollow tubular element for an aerosol generating article, such as the hollow tubular element 100 of the first embodiment described above. The method includes providing apparatus 105 for forming a hollow tubular element. Apparatus 105 comprises a device 107. The device 107 has an inner surface 115 defining a channel 125. The channel 125 extends from an upstream opening 117 of the device 107 to a downstream opening 118 of the device 107.

[0362] The apparatus 107 comprises a first section 126, a second section 127, and a third section 128. The first section is located between the second section 127 and the third section 128, as shown in Figure 10.

[0363] The first section 126 of the device 107 includes an internal projection 135 that protrudes into the channel 125. The internal projection 135 extends from the upstream end of the first section 126 of the device 107 to the downstream end of the first section 126 of the device 107. The channel 125 in the first section 126 of the device 107 is substantially frustoconical, and the diameter of the channel 125 at the upstream end of the first section 126 is greater than the diameter of the channel 125 at the downstream end of the first section 126.

[0364] The internal projection 135 is substantially pyramidal. The internal projection 125 has a substantially triangular cross-section in both the longitudinal and transverse directions. The internal projection 135 has its maximum transverse cross-sectional area at its apex and tapers off at the upstream end of the first section 126 of the apparatus 107. The internal projection includes a first edge, which is adjacent to a portion of the inner surface of the apparatus 107 defining the channel 125. The first edge extends from the upstream end of the first section 126 of the apparatus 107. The internal projection also includes a second edge, which is also adjacent to the inner surface 115 of the apparatus 107 defining the channel. The second edge extends from the upstream end of the first section 126 of the apparatus 107. The internal projection further includes a third edge, which is located within the channel 125 and also extends from the upstream end of the first section 126 of the device 107.

[0365] Figure 11A shows a cross-section of the internal projection 135 taken along plane AA. Figure 11B shows a cross-section of the internal projection 135 taken along plane BB. Therefore, Figure 11B shows a cross-section of the internal projection 135 at its apex.

[0366] The second section 127 of the apparatus 107 extends from the upstream opening 117 of the apparatus 107 to the first section 126 of the apparatus 107. A portion of the channel 125 extending through the second section 127 of the apparatus 107 is substantially cylindrical and has a diameter approximately the same as the diameter of the channel 125 at the upstream end of the first section 126.

[0367] The third section 128 of the apparatus 107 extends from the first section 126 of the apparatus 107 to the downstream opening 118 of the apparatus 107. A portion of the channel 125 extending through the third section 128 of the apparatus 107 is substantially cylindrical and has a diameter approximately the same as the diameter of the channel 125 at the downstream end of the first section 126.

[0368] The method also includes providing a hollow tube 145 formed from a sheet, the circumference of which the hollow tube 145 is approximately equal to the inner circumference of the cross section of the apparatus 107 at the apex of the internal projection 135. The cross section of the hollow tube 145 is shown in Figure 11A. The diameter of the channel 125 at the upstream end of the first section 126 is approximately the same as the diameter of the hollow tube 145. Thus, the diameter of the hollow tube 145 is also approximately the same as the diameter of a portion of the channel 125 extending through the second section 127 of the apparatus 107.

[0369] The method further includes passing the hollow tube 145 through the upstream opening 117 of the device 107 and into the second section 127 of the device 107 along the channel 125.

[0370] The method further includes passing the hollow tube 145 along the channel 125 and in contact with the internal projection 135 at the upstream end of the first section 126 of the device 107.

[0371] The method further includes passing the hollow tube 145 through the first section 126 of the apparatus 107 along the channel 125 such that the outer surface of the hollow tube 145 is in contact with the inner surface 115 of the apparatus 107. In particular, this is done so that the outer surface of the hollow tube 145 is in contact with the internal projection 135. Due to the configuration of the first section 126 of the apparatus 107, passing the hollow tube 145 along the first section 126 of the apparatus 107 causes the hollow tube 145 to deform and conform to the internal shape of the first section of the apparatus 107. In particular, when combined with the presence of the internal projection 135 in the first section 126, the frustoconical shape of the channel 125 in the first section 126 helps to shape the hollow tube 145 into a form with a reduced diameter and an internally folded projection that forms a support element 130, as shown in Figure 12B. As a result, by passing the hollow tube 145 through the first section 126 of the apparatus 107, the hollow tube 145 forms a first fold at the first edge of the internal projection 135, a second fold at the second edge of the internal projection 135, and a third fold at the third edge of the internal projection 135. Thus, by passing the hollow tube 145 through the first section 126 of the apparatus 107, a hollow tubular element formed from the sheet is created, which includes a peripheral portion 110 defining a hollow inner region and a support element 130, the support element 130 being subordinate to the peripheral portion along both the first and second folds of the sheet, and the support element including a third fold of the sheet located within the hollow inner region. The hollow tube 145 and the hollow tubular element are shown by dotted lines in Figure 10.

[0372] The method further includes passing the hollow tubular element out of the channel 117 through a third section 128 of the apparatus 107 and through a downstream opening 118 of the apparatus 107. The third section 128 of the apparatus 107 may assist the hollow tubular element in exiting the apparatus 107. Furthermore, the third section 128 of the apparatus 107 may help maintain the desired shape of the hollow tubular element after it has been folded.

[0373] As shown in Figures 11A and 11B, the internal projection 135 is the first internal projection 135, and the first section 126 of the apparatus 107 includes two additional internal projections, the second internal projection 175 and the third internal projection 185. Each of the internal projections 135, 175, and 185 is identical to one another and is evenly spaced around the perimeter of the first section 126 of the apparatus 107.

[0374] Therefore, as shown in Figure 12B, the support element 130 of the hollow tubular element formed by passing the hollow tube 145 through the first section 126 of the apparatus 107 is the first support element 130, and the hollow tubular element includes two additional support elements, the second support element 170 and the third support element 180. Each of the support elements 130, 170, and 180 is identical to one another and is evenly spaced around the periphery of the hollow tubular element.

Claims

1. A hollow tubular element for an aerosol generating article, wherein the tubular element is A peripheral portion that provides a curved outer surface of the hollow tubular element and defines the hollow inner region of the hollow tubular element, It comprises an internal projection extending into the hollow inner region, The hollow tubular element is formed from a sheet, and the sheet includes a first portion and a second portion adjacent to the first portion, with a first fold in between. The first portion of the sheet forms at least a portion of the peripheral portion of the hollow tubular element, The entirety of the first portion of the sheet forms at least a portion of the curved outer surface of the hollow tubular element, A hollow tubular element for an aerosol generating article, wherein the second portion of the sheet defines the internal projection of the hollow tubular element, and the internal projection extends from the first fold into the hollow inner region of the hollow tubular element.

2. The hollow tubular element according to claim 1, wherein the entirety of the first portion of the sheet forms substantially the entirety of the curved outer surface of the hollow tubular element.

3. The hollow tubular element according to claim 1 or 2, wherein the second portion of the sheet forms a part of the peripheral portion of the hollow tubular element.

4. The hollow tubular element according to any one of claims 1 to 3, wherein the second portion of the sheet includes a second fold.

5. The hollow tubular element according to claim 4, wherein the internal protrusion is subordinate to the peripheral portion along the second fold of the sheet.

6. The hollow tubular element according to claim 4 or 5, wherein the first fold of the sheet and the second fold of the sheet are spaced apart from each other.

7. The hollow tubular element according to any one of claims 4 to 6, wherein the internal protrusion includes a third fold of the sheet.

8. The hollow tubular element according to any one of claims 1 to 7, wherein the internal protrusion has a substantially triangular cross-section.

9. The hollow tubular element according to any one of claims 1 to 8, wherein substantially the entire peripheral portion is formed from a single layer of the sheet.

10. A hollow tubular element according to any one of claims 1 to 8, wherein a portion of the peripheral portion is formed from the first portion of the sheet and a further layer of the sheet, and the first portion of the sheet forms the outermost layer of that portion of the peripheral portion.

11. The hollow tubular element according to any one of claims 1 to 10, wherein the internal projection includes a tip, and the tip is located within the hollow inner region.

12. The hollow tubular element according to any one of claims 1 to 11, wherein the internal protrusion is configured such that the hollow inner region consists of a single channel.

13. The hollow tubular element according to any one of claims 1 to 12, wherein the internal protrusion penetrates the radial center of the hollow tubular element.

14. A hollow tubular element according to any one of claims 1 to 13, further comprising a ventilation zone positioned along the length of the hollow tubular element.

15. An aerosol generating article comprising a hollow tubular element as described in any one of claims 1 to 14.

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