RU2845910C1 - Aerosol-generating article with tubular element - Google Patents

Abstract

FIELD: smoking accessories.

SUBSTANCE: aerosol-generating article comprises a plurality of elements assembled in form of rod (11). Elements include first element (100, 11) comprising an aerosol-generating substrate, and tubular element (100, 200, 300, 500, 600, 700, 800) located upstream or downstream of first element (100, 11). Tubular element (100, 200, 300, 500, 600, 700, 800) comprises: tubular body (103, 203) defining cavity (106, 206, 606) extending from first end (101) of tubular body (103, 203) to second end (102) of tubular body (103, 203); and bent end part forming first end wall (104, 105, 204A, 604, 804) at first end (101) of tubular housing (103, 203). First end wall (104, 105, 204A, 604, 804) defines opening (105, 205A, 205B, 605B, 605) for air flow between cavity (106, 206, 606) and outer side of tubular element (100, 200, 300, 500, 600, 700, 800).

EFFECT: disclosed is an aerosol-generating article with a tubular element.

15 cl, 8 dwg

Description

The present invention relates to an aerosol generating article comprising an aerosol generating substrate and adapted to produce an inhalable aerosol upon heating.

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

In a number of prior art documents, aerosol generating devices for consuming aerosol generating articles are disclosed. Such devices include, for example, electrically heated aerosol generating devices, in which the aerosol is generated by transferring heat from one or more electrical heating elements of the aerosol generating device to an aerosol generating substrate of the heated aerosol generating article. For example, electrically heated aerosol generating devices have been proposed, which comprise an internal heater plate, which is adapted to be inserted into an aerosol generating substrate. As an alternative, inductively heated aerosol generating articles have been proposed in WO 2015/176898, comprising an aerosol generating substrate and a current collecting element, located inside the aerosol generating substrate.

Aerosol-generating articles in which the tobacco-containing substrate is heated rather than burned pose a number of challenges that have not been encountered with conventional smoking articles. For example, it may be desirable to limit the movement of the aerosol-generating substrate within the aerosol-generating article while still providing a sufficient level of airflow that can pass through the aerosol-generating substrate and the aerosol-generating article. Limiting the potential movement of the aerosol-generating substrate is particularly desirable because it may help improve the consistency of performance from one article to another, for example by helping to increase the consistency of the interaction between the aerosol-generating substrate and the heater element. This may be particularly relevant for aerosol-generating articles that are adapted to accommodate a heater plate, since the process of inserting the heater plate may otherwise increase the likelihood of the aerosol-generating substrate becoming dislodged.

In document WO 2013/098405 it is proposed to include a support element immediately downstream of the aerosol generating substrate. The support element is provided in the form of an annular tube of filter material, often referred to as a hollow acetate tube. The support element is configured to resist movement of the aerosol generating substrate downstream during the insertion of a heating plate of the aerosol generating device into the aerosol generating substrate. An empty space within the hollow support element provides an opening for the passage of aerosol from the aerosol generating substrate to the mouth end of the aerosol generating article.

However, some support elements, such as hollow acetate tubes, may undesirably filter some volatile compounds released from the aerosol-generating substrate. Moreover, some support elements may not provide the desired RTD properties for an aerosol-generating article. Prior art support elements, such as hollow acetate tubes, may also be expensive or expensive and difficult to manufacture. Prior art support elements, such as hollow acetate tubes, may also not be ideally suited for aerosol-generating articles in which the current collecting element is located within the aerosol-generating substrate. For example, because the prior art support element may not be ideally suited for the temperatures generated by the current collecting element.

It would therefore be desirable to provide a new and improved aerosol generating article adapted to achieve at least one of the desired results described above. It would also be desirable to provide such an aerosol generating article that could be manufactured efficiently and at high speed, preferably with a satisfactory RTD and low RTD variability from one article to another.

The present invention relates to an aerosol-generating article. The aerosol-generating article may comprise a plurality of elements assembled in the form of a rod. The plurality of elements may comprise a first element comprising an aerosol-generating substrate. The plurality of elements may comprise a tubular element located upstream or downstream of the first element. The tubular element may comprise a tubular body forming a cavity. The cavity may extend from the first end of the tubular body to the second end of the tubular body. The tubular element may further comprise a bent end portion forming a first end wall at the first end of the tubular body. The first end wall may define an opening for air flow between the cavity and the outer side of the tubular element. The first end wall may be adjacent to the aerosol-generating substrate.

According to the first aspect of the present invention, an aerosol generating article is provided, comprising a plurality of elements assembled in the form of a rod, wherein the elements include: a first element comprising an aerosol generating substrate; and a tubular element located upstream or downstream relative to the first element, wherein the tubular element comprises: a tubular body forming a cavity extending from a first end of the tubular body to a second end of the tubular body; and a bent end portion forming a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outer side of the tubular element. The first end wall can be adjacent to the aerosol generating substrate.

According to a second aspect of the present invention, there is provided an aerosol generating article comprising a plurality of elements assembled in the form of a rod, wherein the elements include: a first element comprising an aerosol generating substrate; and a tubular element located upstream or downstream relative to the first element, wherein the tubular element comprises a tubular body defining a cavity extending from a first end of the tubular body to a second end of the tubular body; and a bent end portion defining a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outer side of the tubular element; and wherein the aerosol generating article further comprises an outer wrapper surrounding at least the tubular element.

The outer wrapper may form the outer surface of the aerosol-generating article. The outer wrapper may also surround the first element. The outer wrapper may surround all of the plurality of elements of the aerosol-generating article that are assembled in the form of a rod. The outer wrapper may be a rim wrapper, as described below. The outer wrapper surrounding the tubular element may be a paper wrapper or a non-paper wrapper. Paper wrappers suitable for use in particular embodiments of the present invention are known in the art and include, but are not limited to: types of cigarette paper and filter wicks. Non-paper wrappers suitable for use in particular embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco materials. In certain preferred embodiments, the wrapper may be formed from a laminated material comprising a plurality of layers. Preferably, the wrapper is formed from an aluminum multilayer sheet. The use of a multi-layer sheet containing aluminum primarily prevents combustion of the outer wrapper in the event that the aerosol generating substrate is to be ignited rather than heated as intended.

According to a third aspect of the present invention, an aerosol generating article is provided, comprising a plurality of elements assembled in the form of a rod, wherein the elements include: a first element comprising an aerosol generating substrate; and a tubular element located entirely upstream or entirely downstream relative to the first element, wherein the tubular element comprises a tubular body defining a cavity extending from a first end of the tubular body to a second end of the tubular body; and a bent end portion defining a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outer side of the tubular element.

The term "aerosol-generating article" is used in this document to refer to an article in which an aerosol-generating substrate is heated to produce and deliver an inhalable aerosol to a user. In the context of this document, the term "aerosol-generating substrate" means a substrate capable of releasing volatile compounds when heated to generate an aerosol.

A conventional cigarette is lit when the 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 causes the end of the cigarette to ignite, and the resulting combustion generates inhaled smoke. By comparison, in heated aerosol-generating articles, the aerosol is generated by heating a flavor-generating substrate, such as tobacco. Known heated aerosol-generating articles include, for example, electrically heated aerosol-generating articles and aerosol-generating articles in which the aerosol is generated by transferring heat from a combustible heat-generating element or heat source to a physically separate aerosol-forming material. For example, the aerosol generating articles according to the present invention find particular application in aerosol generating systems comprising an electrically heated aerosol generating device having an internal heater plate which is adapted to be inserted into a rod of a substrate generating the aerosol. Aerosol generating articles of this type are described in the prior art, for example in document EP 0 822 670.

As used herein, the term "aerosol generating device" refers to a device that includes a heating element that interacts with an aerosol generating substrate of an aerosol generating article to generate an aerosol.

In the context of this document, the term "rod" is used to refer to a generally cylindrical member with a substantially circular, oval or elliptical cross-section.

In the context of this document, the term "longitudinal" refers to the direction corresponding to the major longitudinal axis of the aerosol-generating article that extends between the upstream and downstream ends of the aerosol-generating article. In the context of this document, the terms "upstream" and "downstream" describe the relative positions of elements or parts of elements of the aerosol-generating article with respect to the direction in which the aerosol is transported through the aerosol-generating article during use.

During use, air is drawn through the aerosol-generating article in the longitudinal direction. The term "cross" refers to the direction that is perpendicular to the longitudinal axis. Any reference to a "section" of the aerosol-generating article or a component of the aerosol-generating article refers to the cross-section unless otherwise specified.

The term "length" refers to the dimension of a component of an aerosol-generating article in the longitudinal direction. For example, it can be used to refer to the dimension of a first element containing an aerosol-generating substrate or a hollow tubular element in the longitudinal direction.

In the context of this document, the term "tubular element" is used to denote a generally elongated element that defines a lumen or passage for air flow along its longitudinal axis. In particular, the term "tubular" will be used hereinafter in relation to a tubular element that has a tubular body with a substantially cylindrical cross-section and that defines at least one passage for air flow that provides continuous fluid communication between an upstream end of the tubular body and a downstream end of the tubular body. However, it should be understood that alternative geometric shapes (e.g., alternative cross-sectional shapes) of the tubular body may be possible.

In the context of this document, the term "elongated" means that the element has a length dimension that is greater than its width dimension or its diameter dimension, such as twice or greater than its width dimension or its diameter dimension.

In the context of the present invention, the tubular body of the tubular element provides an unrestricted flow channel. This means that a portion of the tubular body of the tubular element provides a low level of resistance to draw (RTD). Therefore, the flow channel must be free of any components that can restrict the air flow in the longitudinal direction. Preferably, the flow channel is substantially empty. In such a case, the tubular body of the tubular element forms an empty cavity.

The tubular element according to the present invention provides an improved component for an aerosol-generating article. By forming the tubular element from a tubular body that forms a cavity extending from the first end of the tubular body to the second end of the tubular body, a relatively large portion of the tubular element can be empty and provide unimpeded air flow. If the tubular element is located downstream of the aerosol-generating substrate, this can help improve the cooling and nucleation of the aerosol. Moreover, such a configuration can also help to minimize the filtration of any compounds released from the aerosol-generating substrate, especially compared to the hollow acetate tubes of the prior art.

By providing the tubular element with a bent end portion forming a first end wall at the first end of the tubular body, the tubular element can be configured to have a desired RTD by configuring the size and shape of the first end wall. In particular, the tubular element and its first end wall can be manufactured efficiently and at high speed, with a satisfactory RTD and low variability of RTD from one product to another. Moreover, the configuration of the tubular element and its first end wall means that the RTD can be localized in a certain longitudinal position of the tubular element, rather than continuously distributed along the length of the tubular element.

In the case where the first end wall of the tubular element is adjacent to the aerosol-generating substrate, the first end wall can provide a partition that can limit the movement of the aerosol-generating substrate. This arrangement can also advantageously provide the passage of one or both of the air and the aerosol through the opening into the cavity.

The partition provided by the first end wall of the tubular element may be more effective than the partition provided by the end of the hollow acetate tube, since the first end wall may be less deformable than the end of the hollow acetate tube. The design of the tubular element may also be better adapted to withstand the temperatures generated by the heating plate or the current collecting element.

The term "adjacent to" is used in this document with respect to the tubular element and the first element to indicate that the tubular element is located longitudinally adjacent to the first element in the rod of the assembled elements. In particular, this term indicates the absence of other elements of the assembled rod located between the first element and the tubular element in the longitudinal direction.

The first element and the tubular element may be adjacent to each other and in contact with each other. For example, the first end wall of the tubular element may be adjacent to the aerosol-generating substrate and in contact with the aerosol-generating substrate.

The first element and the tubular element may be adjacent to each other, but not in contact with each other, since a small gap of free space separates the first element from the tubular element in the longitudinal direction of the aerosol-generating article. For example, the first end wall of the tubular element may be adjacent to the aerosol-generating substrate, but not in contact with the aerosol-generating substrate. The gap may be 2 millimeters or less. The gap may be 1 millimeter or less.

The first element can be called the aerosol generating element.

The tubular element may be located entirely upstream of the first element. In such embodiments, the tubular element may be referred to as an upstream tubular element.

The tubular element may be located completely downstream of the first element. In such embodiments, the tubular element may be referred to as a downstream tubular element.

The aerosol generating article may comprise two tubular elements, one of which is a first tubular element located entirely downstream of the first element, and the other is a second tubular element located entirely upstream of the first element. Each of the first and second tubular elements may have any feature or combination of features described above or below with respect to the tubular element according to the present invention.

For example, the tubular element may be a first tubular element that is located downstream relative to the aerosol-forming substrate, wherein the first end wall of the first tubular element is adjacent to the downstream end of the aerosol-generating substrate. In such embodiments, the aerosol-generating article may further comprise a second tubular element. The second tubular element may be located upstream relative to the first element. The second tubular element may comprise a tubular body that defines a cavity that extends from the first end of the tubular body to the second end of the tubular body; and a bent end portion that defines a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outer side of the second tubular element. The first end wall of the second tubular element may be adjacent to the upstream end of the aerosol-generating substrate. Therefore, in such embodiments, the first element containing the aerosol-generating substrate can be placed between the first and second tubular elements, wherein each tubular element has a bent end portion that provides a corresponding end wall adjacent to the upstream or downstream end of the first element. In such embodiments, the second tubular element can be called the upstream tubular element, and the first tubular element can be called the downstream tubular element.

The second tubular element may further comprise a bent end portion forming a second end wall at the second end of its tubular body. The second end wall of the second tubular element may define an opening for air flow between the cavity and the outer side of the second tubular element. The opening defined by the second end wall of the second tubular element may be smaller than the opening defined by the first end wall of the second tubular element. For example, the size of the opening defined by the second end wall of the second tubular element may be from about 20 percent to about 80 percent of the size of the opening defined by the first end wall of the second tubular element. The size of the opening defined by the second end wall of the second tubular element may be from about 40 percent to about 60 percent of the size of the opening defined by the first end wall of the second tubular element, more preferably from about 45 percent to about 55 percent of the size of the opening defined by the first end wall of the second tubular element.

In general, when the tubular element according to the present invention comprises two end walls, each of which has a corresponding opening, the size of the opening defined by the second end wall of the tubular element can be from about 20 percent to about 80 percent of the size of the opening defined by the first end wall of the tubular element.

The second tubular element may be an upstream component of the aerosol-generating article. For example, the upstream end of the aerosol-generating article may be formed by the upstream end of the second tubular element.

As will be described in more detail below, the aerosol generating article may further comprise a ventilation zone at a location along the tubular element. In the case where the aerosol generating article comprises the first and second tubular elements described above, the ventilation zone is preferably located along the first tubular element.

The first end wall may extend substantially across the longitudinal direction of the aerosol-generating article. The first end wall may extend substantially across the longitudinal direction of the tubular body.

The first end wall can partially extend into the cavity of the tubular body and forms an angle of less than 90 degrees with the inner surface of the tubular body, more preferably an angle of less than 80 degrees with the inner surface of the tubular body, even more preferably an angle of less than 70 degrees with the inner surface of the tubular body. This can be achieved by applying a bending force to the tubular element during the manufacture of the tubular element, as a result of which at least a part of the first end portion of the tubular element is pressed into the cavity of the tubular body. Such designs can advantageously increase the probability that the first end wall will remain stationary with respect to the tubular body after the manufacture of the tubular element. In particular, such designs can help to overcome any natural elasticity of the material forming the tubular element, as a result of which the bent end portion of the tubular element is less likely to return to its original state after manufacture.

The opening defined by the first end wall may be the only opening in the first end wall. The opening may be located generally in the radial central position of the tubular element. The first end wall may have a generally annular shape.

The first end wall may extend from a bending point on the tubular member and to a radially central position of the tubular member. The bending point may typically correspond to a first end of the tubular body of the tubular member.

Preferably, at least the first part of the tubular element forming the first end wall is substantially airtight. In other words, the first end wall is preferably substantially non-porous. Preferably, the first end wall does not contain perforations. The material forming the first end wall may have a porosity of less than 2000 Coresta units. The material forming the first end wall may have a porosity of less than 1000 Coresta units. The material forming the first end wall may have a porosity of less than 500 Coresta units.

If the first element comprises a current-collecting element within the aerosol-generating substrate, the opening in the first wall may be generally aligned with the radial position of the current-collecting element. This may advantageously contribute to maintaining a distance between the first end wall of the tubular element and the current-collecting element of the first element. Maintaining such a distance may contribute to reducing any undesirable heating of the first end wall of the tubular element by the current-collecting element.

The present invention also includes a method for forming a tubular element for an aerosol-generating article according to the present invention. The method may include the step of providing a precursor of a tubular element comprising: a tubular body defining a cavity extending from a first end of the tubular body to a second end of the tubular body; and a first end portion adjacent to the first end of the tubular body and formed integrally with it. The method further includes the step of applying a bending force to the precursor of the tubular element for bending or flexing the first end portion about a bending point corresponding to the first end of the tubular body, wherein the bending force is applied in such a way that at least a portion of the first end portion of the tubular element extends into the cavity of the tubular body. The method may further include the step of weakening the bending force so that the first end portion of the tubular element partially returns back along its bending path and reaches a position in which the first end portion extends substantially across the longitudinal direction of the tubular body to thereby form a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outer side of the tubular element.

The present invention also includes a tubular element for an aerosol-generating article. The tubular element may comprise: a tubular body defining an empty cavity extending from a first end of the tubular body to a second end of the tubular body; a first bent end portion defining a first end wall at the first end of the tubular body, wherein the first end wall defines a first opening for air flow between the empty cavity and the outer side of the tubular element; and a second bent end portion defining a second end wall at the second end of the tubular body, wherein the second end wall defines a second opening for air flow between the empty cavity and the outer side of the tubular element. The tubular element may comprise or be combined with any feature or combination of features that are described above or below in relation to the tubular element of the aerosol-generating article according to the present invention.

The tubular element preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article. In the case where the first element is formed in the form of a rod, the tubular element preferably has an outer diameter approximately equal to the outer diameter of the first element.

The tubular element may have an outer diameter of 6 millimeters to 10 millimeters, such as 7 millimeters to 9 millimeters or 7.5 millimeters to 8.5 millimeters. In a preferred embodiment, the tubular element has an outer diameter of 7.8 millimeters plus or minus 10 percent.

Preferably, the tubular element has an equivalent internal diameter of at least about 5.5 millimeters. More preferably, the tubular element has an equivalent internal diameter of at least about 6 millimeters. Even more preferably, the tubular element has an equivalent internal diameter of at least about 7 millimeters. The term "equivalent internal diameter" is used herein to denote the diameter of a circle that has the same cross-sectional surface area of the air flow passage formed inside the hollow tubular segment. The cross-section of the air flow passage may have any suitable shape. However, as briefly described above, a circular cross-section is preferred, i.e. the hollow tubular segment is actually a cylindrical tube. In this case, the equivalent internal diameter of the hollow tubular segment is actually the same as the internal diameter of the cylindrical tube.

The equivalent internal diameter of the hollow tubular segment is preferably less than about 10 millimeters. More preferably, the equivalent internal diameter of the hollow tubular segment is less than about 9.5 millimeters, even more preferably less than 9 millimeters.

Preferably, the tubular element has a wall thickness of at least about 0.1 millimeter, more preferably at least about 0.2 millimeter.

Preferably, the tubular element has a wall thickness of less than about 1.5 millimeters, preferably less than about 1.25 millimeters. In a preferred embodiment, the tubular element has a wall thickness of less than about 1 millimeter.

Thus, the tubular element preferably has a wall thickness of from about 0.1 millimeter to about 1.5 millimeters, or from about 0.2 millimeters to about 1.25 millimeters, or from about 0.5 millimeters to about 1 millimeter.

Providing a tubular member with such a wall thickness can contribute to improving the ultimate strength of the tubular body against crushing or deformation, while allowing the first end wall to be formed by a bent end portion of the tubular member.

The wall thickness of the tubular element may be the same as the wall thickness of one or both of the tubular body and the first end wall.

The length of the tubular element may be substantially the same as the length of the tubular body.

Preferably, the tubular element has a length of at least about 10 millimeters, more preferably at least about 15 millimeters.

Preferably, the tubular element has a length of less than about 30 millimeters, preferably less than about 25 millimeters, even more preferably less than about 20 millimeters.

The tubular element may have a length of about 10 millimeters to about 30 millimeters, preferably about 15 millimeters to about 25 millimeters, more preferably about 15 millimeters to about 20 millimeters. For example, in one particularly preferred embodiment, the tubular element has a length of 18 millimeters. Such lengths may be particularly preferred in embodiments in which the tubular element is located downstream of the aerosol-generating substrate, wherein the first end wall of the tubular element is adjacent to the downstream end of the aerosol-generating substrate.

The tubular element may have a length of about 5 millimeters to about 20 millimeters, preferably about 8 millimeters to about 15 millimeters, more preferably about 10 millimeters to about 13 millimeters. For example, in one particularly preferred embodiment, the tubular element has a length of 12 millimeters. Such lengths may be particularly preferred in embodiments in which the tubular element is located upstream of the aerosol-generating substrate, wherein the first end wall of the tubular element is adjacent to the upstream end of the aerosol-generating substrate.

Preferably, the tubular element is adapted to generate an RTD of from about 0 millimeters of water (about 0 Pa) to about 20 millimeters of water (about 100 Pa), more preferably from about 0 millimeters of water (about 0 Pa) to about 10 millimeters of water (about 100 Pa).

The tubular element is preferably formed from a paper material, such as paper, thin cardboard or cardboard. The tubular element can be formed from a plurality of overlapping layers of paper, such as a plurality of layers of paper wound in parallel, or a plurality of layers of paper wound in a spiral. The formation of the tubular element from a plurality of overlapping layers of paper can contribute to increasing the ultimate strength of the tubular body against crushing or deformation, while allowing the first end wall to be formed by means of a bent end portion of the tubular element.

The tubular element may comprise at least two layers of paper. The tubular element may comprise less than eleven layers of paper.

In case the tubular element is formed from a paper material, the paper material may have a basis weight of at least about 90 grams per square meter. The paper material may have a basis weight of less than about 300 grams per square meter. The paper material may have a basis weight of about 100 to about 200 grams per square meter. Providing the tubular element with such a basis wall weight may contribute to improving the ultimate strength of the tubular body against crushing or deformation, while allowing the first end wall to be formed by means of the bent end portion of the tubular element.

The first end wall of the tubular element may comprise a hydrophobic region comprising hydrophobic groups covalently bound to the first end wall. In the event that the tubular element comprises a second end wall, the second end wall may also comprise a hydrophobic region.

In another aspect, the hydrophobic region has a contact angle of at least about 90 degrees or at least about 100 degrees and a measured Cobb surface water absorption value (after 60 seconds) of about 40 g/ ^m2 or less or about 35 g/ ^m2 or less.

The hydrophobic region can be obtained by a process comprising the steps of: applying a liquid composition containing a fatty acid halide to the surface of the first end wall and maintaining the surface temperature from about 120 degrees Celsius to about 180 degrees Celsius. The fatty acid halide reacts in situ with the protogenic groups of the material in the hydrophobic region, which leads to the formation of fatty acid esters.

The term "hydrophobic" refers to a surface that exhibits water-repellent properties. One commonly used method of measuring this is by measuring the water contact angle. The "water contact angle" is the angle, usually measured by a liquid, where the liquid/vapor interface meets a solid surface. In quantitative terms, it represents the wettability of the solid surface by the liquid according to Young's equation.

This hydrophobic region has a Cobb surface water absorption value (ISO535:1991) (after 60 seconds) of less than approximately 40 g/ ^m2 , less than approximately 35 g/ ^m2 , less than approximately 30 g/ ^m2 or less than approximately 25 g/ ^m2 .

The hydrophobic region has a contact angle of at least about 90 degrees, at least about 95 degrees, at least about 100 degrees, at least about 110 degrees, at least about 120 degrees, at least about 130 degrees, at least about 140 degrees, at least about 150 degrees, at least about 160 degrees, or at least about 170 degrees. Hydrophobicity is determined using the TAPPI T558 om-97 test and the result is reported as an interface contact angle expressed in "degrees" that can range from zero degrees to about 180 degrees. If the contact angle is not indicated together with the term "hydrophobic", then the water contact angle is at least 90 degrees.

According to the present invention, an aerosol generating article is provided for generating an inhalable aerosol upon heating. The aerosol generating article comprises a first element comprising an aerosol generating substrate and a tubular element. The aerosol generating article comprises a downstream section at a location downstream of the aerosol generating substrate. The downstream section may comprise one or more downstream elements, such as the tubular element.

The downstream section may comprise a mouthpiece element. The mouthpiece element may extend all the way to the mouthpiece end of the aerosol generating article.

The mouthpiece element may extend the entire distance to the downstream end of the aerosol generating substrate. If the mouthpiece element extends the entire distance from the downstream end of the aerosol generating substrate to the mouthpiece end of the aerosol generating article, the mouthpiece element may be the only element in the downstream section of the aerosol generating article. Alternatively, when the tubular element is located downstream relative to the aerosol generating substrate, the mouthpiece element may be located downstream relative to the first tubular element. In such embodiments, the mouthpiece element may extend the entire distance to the downstream end of the tubular element. In other words, the mouthpiece element is located immediately downstream relative to the tubular element. As an example, the mouthpiece element may adjoin the downstream end of the tubular element.

The mouthpiece element is preferably arranged at the downstream end or mouthpiece end of the aerosol-generating article. The mouthpiece element preferably comprises at least one mouthpiece filter segment for filtering the aerosol generated from the aerosol-generating substrate. For example, the mouthpiece element may comprise one or more segments of fibrous filter material. Suitable fibrous filter materials will be known to a person skilled in the art. Particularly preferably, at least one mouthpiece filter segment comprises a cellulose acetate filter segment formed from a cellulose acetate rod.

The mouthpiece element may consist of a single filtering mouthpiece segment. In alternative embodiments, the mouthpiece element comprises two or more filtering mouthpiece segments coaxially aligned with one another in end-to-end contact.

The mouthpiece element may comprise a mouthpiece end cavity. The mouthpiece end cavity may be defined by a hollow tubular element provided at a downstream end of the mouthpiece. Alternatively, the mouthpiece end cavity may be formed by an outer wrapper of the aerosol-generating article at the mouthpiece end.

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

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

Preferably, the mouthpiece is formed from a segment of fibrous filter material.

Preferably, the mouthpiece element is surrounded by a wick. Preferably, the mouthpiece element is not ventilated, so that air does not enter the aerosol-generating article along the mouthpiece element.

The mouthpiece element is preferably connected to one or more adjacent upstream components of the aerosol generating article, such as a tubular element or tubular elements, via a rim wrap.

Preferably, the mouthpiece element has an RTD of less than about 25 millimeters of water column. More preferably, the mouthpiece element has an RTD of less than about 20 millimeters of water column. Even more preferably, the mouthpiece element has an RTD of less than about 15 millimeters of water column.

RTD values of from about 10 millimeters of water column to about 15 millimeters of water column are particularly preferred since a mouthpiece element having one such RTD value, which makes a minimal contribution to the overall RTD of the aerosol-generating article, is expected to have substantially no filtering effect on the aerosol delivered to the consumer.

The mouthpiece element preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating article. The mouthpiece element may have an outer diameter of about 5 millimeters to about 10 millimeters or about 6 millimeters to about 8 millimeters. In a preferred embodiment, the mouthpiece element has an outer diameter of about 7.2 millimeters.

The mouthpiece element may have a length of at least about 10 millimeters, more preferably at least about 11 millimeters, 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, more preferably less than about 15 millimeters.

The mouthpiece element may have a length of about 10 millimeters to about 25 millimeters, more preferably about 10 millimeters to about 20 millimeters, even more preferably about 10 millimeters to about 15 millimeters. The mouthpiece element may have a length of about 11 millimeters to about 25 millimeters, more preferably about 11 millimeters to about 20 millimeters, even more preferably about 11 millimeters to about 15 millimeters. The mouthpiece element may have a length of about 12 millimeters to about 25 millimeters, more preferably about 12 millimeters to about 20 millimeters, even more preferably about 12 millimeters to about 20 millimeters.

In a preferred embodiment, the mouthpiece element has a length of approximately 12 millimeters.

Providing a relatively long mouthpiece element in an aerosol generating article may allow for inclusion of a capsule or provide greater rigidity to the article when the user applies lips, or both.

The aerosol generating article may comprise a ventilation zone at a location along the downstream section. If the downstream section comprises a tubular element, the ventilation zone may be provided at a location along the tubular element.

The tubular element according to the present invention may comprise a ventilation zone at a location along the tubular body of the tubular element. The features of the ventilation zone are described below with respect to the aerosol-generating article. However, it should be understood that they may also relate directly to the tubular element itself.

The ventilation zone can be located at a distance of approximately 5 millimeters to approximately 15 millimeters from the bent end portion of the tubular element. The ventilation zone can be located at a distance of at least 2 millimeters from the bent end portion of the tubular element, more preferably at least 3 millimeters from the bent end portion of the tubular element, even more preferably at least 5 millimeters from the bent end portion of the tubular element.

The ventilation zone can be located at a distance of less than 20 millimeters from the bent end portion of the tubular element, more preferably less than 15 millimeters from the bent end portion of the tubular element, even more preferably less than 10 millimeters from the bent end portion of the tubular element.

If the tubular element is a first tubular element located downstream of the aerosol-forming substrate, the ventilation zone is preferably located in a downstream section of the first tubular element. Preferably, the ventilation zone is located at a distance of from about 1 millimeter to about 10 millimeters from the downstream end of the first tubular element, more preferably from about 2 millimeters to about 8 millimeters from the downstream end of the first tubular element, even more preferably from about 3 millimeters to about 6 millimeters from the downstream end of the first tubular element.

Preferably, the ventilation zone is located at a distance of at least 1 millimeter from the downstream end of the first tubular element, more preferably, the ventilation zone is located at a distance of at least 2 millimeters from the downstream end of the first tubular element, even more preferably, the ventilation zone is located at a distance of at least 3 millimeters from the downstream end of the first tubular element.

Preferably, the ventilation zone is located at a distance of less than 10 millimeters from the downstream end of the first tubular element, more preferably, the ventilation zone is located at a distance of less than 8 millimeters from the downstream end of the first tubular element, even more preferably, the ventilation zone is located at a distance of less than 6 millimeters from the downstream end of the first tubular element.

The ventilation zone may comprise a plurality of perforations in the peripheral wall of the ventilated element, which may be a tubular element. Preferably, the ventilation zone comprises at least one annular row of perforations, the ventilation zone may comprise two annular rows of perforations. For example, the perforations may be formed on a production line during the manufacturing process of an aerosol-generating article. Preferably, each annular row of perforations comprises from 8 to 30 perforations.

The aerosol generating article of the present invention may have a ventilation level of at least about 5 percent.

The term "ventilation level" is used throughout this specification to mean the volumetric ratio between the airflow admitted into the aerosol-generating article through the ventilation zone (ventilation airflow) and the sum of the aerosol-containing airflow and the ventilation airflow. The higher the ventilation level, the greater the dilution of the aerosol flow delivered to the consumer.

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

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

In particularly preferred embodiments, the aerosol-generating article has a ventilation level of about 30 percent. The aerosol-generating article may have a ventilation level of about 20 percent to about 60 percent, preferably about 20 percent to about 45 percent, more preferably about 20 percent to about 40 percent. The aerosol-generating article may have a ventilation level of about 25 percent to 60 percent, preferably about 25 percent to about 45 percent, more preferably about 25 millimeters to about 40 percent. In further embodiments, the aerosol-generating article has a ventilation level of about 30 percent to about 60 percent, preferably about 30 percent to about 45 percent, more preferably about 30 percent to about 40 percent.

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

Embodiments in which the aerosol generation comprises a first tubular element downstream of the aerosol generating substrate with a ventilation zone provided at a location along the first tubular element may provide a number of advantages. For example, without being limited by theory, the inventors have found that the temperature difference caused by the admission of cooler external air into the first tubular element through the ventilation zone may have a positive effect on the nucleation and growth of aerosol particles.

The formation of an aerosol from a gaseous mixture containing various chemical compounds depends on the subtle interactions of nucleation, evaporation and condensation, and droplet coalescence, while taking into account changes in vapor concentration, temperature and velocity fields. The so-called classical nucleation theory is based on the assumption that a fraction of molecules in the gas phase is large enough to remain coherent for a long time with a sufficient probability (e.g. fifty-fifty probability). These molecules represent some kind of critical threshold molecular clusters among short-lived molecular aggregates, meaning that, in general, smaller molecular clusters in the gas phase are more likely to disintegrate quickly enough, while larger clusters are, in general, more likely to grow. Such a critical cluster is identified with the key nucleation nucleus from which droplet growth is expected due to condensation of molecules from the vapor. Primary droplets that have just formed are assumed to appear with a certain initial diameter and can then grow by several orders of magnitude. This is simplified and can be accelerated by rapid cooling of the surrounding vapor, which causes condensation. Thus, it helps to consider that evaporation and condensation are two sides of the same mechanism, namely mass transfer between a gas and a liquid. Whereas evaporation refers to a net mass transfer from the liquid droplets to the gas phase, condensation is a net mass transfer from the gas phase to the droplet phase. Evaporation (or condensation) will cause a decrease in volume (or growth) of the droplets, but will not change the number of droplets.

In this scenario, which may be further complicated by droplet coalescence phenomena, temperature and cooling rate may play an important role in determining the response of the system. In general, different cooling rates may result in significantly different time behavior with respect to liquid phase (droplet) formation, since the nucleation process is typically nonlinear. Without being limited by theory, it is suggested that cooling may cause a rapid increase in droplet number concentration, followed by a strong short-term increase in droplet growth (nucleation burst). This nucleation burst may be more significant at lower temperatures. It may also be that higher cooling rates may favor an earlier onset of nucleation. In contrast, a decrease in the cooling rate may have a beneficial effect on the final size that the aerosol droplets eventually reach.

Thus, the rapid cooling caused by the admission of external air into the first tubular element through the ventilation zone can be advantageously used to promote the nucleation and growth of aerosol droplets. However, at the same time, the immediate disadvantage of admitting external air into the first tubular element is the dilution of the aerosol stream delivered to the consumer.

The inventors of the present invention have surprisingly found that the effect of dilution on the aerosol, which can be assessed by measurement, in particular the effect on the delivery of the aerosol forming substance (such as glycerol) contained in the aerosol generating substrate, is advantageously minimized when the ventilation level is within the ranges described above. In particular, it has been found that ventilation levels from 25 percent to 50 percent, and even more preferably from 28 to 42 percent, lead to particularly satisfactory values of glycerol delivery. At the same time, the duration of nucleation and, therefore, the delivery of nicotine and the aerosol forming substance (such as glycerol) are improved.

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

This is particularly advantageous for "short" aerosol-generating articles, such as articles in which the length of the first element containing the aerosol-generating substrate is less than about 40 millimeters, preferably less than 25 millimeters, even more preferably less than 20 millimeters, or in which the overall length of the aerosol-generating article is less than about 70 millimeters, preferably less than about 60 millimeters, even more preferably less than 50 millimeters. It should be understood that in such aerosol-generating articles there is little time and space for the aerosol to form and for the particulate phase of the aerosol to be available for delivery to the consumer.

In addition, since the ventilated first tubular element can be designed to not contribute significantly to the overall RTD of the aerosol-generating article, in such aerosol-generating articles, the overall RTD of the article can be advantageously precisely controlled by adjusting the length and density of the first element containing the aerosol-generating substrate, or the length and optionally the length and density of the filter material segment forming part of the mouthpiece, or the length and density of the element provided upstream of the first element containing the aerosol-generating substrate. In this way, aerosol-generating articles that have a given RTD can be manufactured with high quality and greater accuracy, so that satisfactory RTD levels can be provided to the consumer even in the presence of ventilation.

Moreover, the inventors have found that improved mixing of hot air from an aerosol-generating substrate with fresh air from ventilation drawn in through ventilation openings can be achieved by providing ventilation in a tubular element having a bent end portion forming a first end wall at a first end of the tubular body, wherein the first end wall limits an opening for air flow between the cavity and the outside of the tubular element. In particular, without being limited by theory, it is believed that a combination of a partial restriction of the air flow created by the first end wall with the presence of incoming air from ventilation can be particularly effective in facilitating mixing of hot air drawn in through the aerosol-generating substrate with fresh air drawn in through the ventilation openings.

The aerosol generating article may further comprise an upstream section at a location upstream of the aerosol generating substrate. The upstream section may comprise one or more upstream elements, such as a tubular element according to the present invention. The upstream section may comprise an upstream element located immediately upstream of the rod of the aerosol generating substrate. The upstream element may be a tubular element according to the present invention, such as the second tubular element described above.

The first element containing the aerosol-generating substrate may further contain a current-receiving element located inside the aerosol-generating substrate. The current-receiving element may be an elongated current-receiving element. The current-receiving element may extend longitudinally inside the aerosol-generating substrate. The current-receiving element is designed to be in thermal contact with the aerosol-generating substrate.

In the context of this document, the term "current collecting element" refers to a material that can convert electromagnetic energy into heat. When placed within a fluctuating electromagnetic field, eddy currents induced in the current collecting element cause the current collecting element to heat up. Since the elongated current collecting element is placed in thermal contact with the aerosol-generating substrate, the aerosol-generating substrate is heated by the current collecting element.

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

The current collecting element is arranged substantially longitudinally within the rod. This means that the lengthwise dimension of the elongated current collecting element is arranged approximately parallel to the longitudinal direction of the rod, for example in the range of plus or minus 10 degrees parallel to the longitudinal direction of the rod. In preferred embodiments, the elongated current collecting element may be arranged in a radially central position within the rod and extends along the longitudinal axis of the rod.

Preferably, the current collecting element extends the entire distance to the downstream end of the first element. The current collecting element may extend the entire distance to the upstream end of the first element. In particularly preferred embodiments, the current collecting 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.

The current collecting element is preferably made in the form of a pin, rod, strip or plate.

The current collecting element preferably has a length of from about 5 millimeters to about 15 millimeters, for example from about 6 millimeters to about 12 millimeters, or from about 8 millimeters to about 10 millimeters.

The ratio between the length of the current collecting element and the total length of the substrate of the aerosol generating article may be from about 0.2 to about 0.35.

Preferably, the ratio between the length of the current-receiving element and the total length of the substrate of the aerosol-generating article is at least about 0.22, more preferably at least about 0.24, even more preferably at least about 0.26. The ratio between the length of the current-receiving element and the total length of the substrate of the aerosol-generating article is preferably less than about 0.34, more preferably less than about 0.32, even more preferably less than about 0.3.

The ratio between the length of the susceptor element and the total length of the substrate of the aerosol-generating article may be from about 0.22 to about 0.34, more preferably from about 0.24 to about 0.34, even more preferably from about 0.26 to about 0.34. The ratio between the length of the susceptor element and the total length of the substrate of the aerosol-generating article may be from about 0.22 to about 0.32, more preferably from about 0.24 to about 0.32, even more preferably from about 0.26 to about 0.32. In further embodiments, the ratio between the length of the susceptor element and the total length of the substrate of the aerosol-generating article is preferably from about 0.22 to about 0.3, more preferably from about 0.24 to about 0.3, even more preferably from about 0.26 to about 0.3.

In a particularly preferred embodiment, the ratio between the length of the current collecting element and the total length of the substrate of the aerosol generating article is approximately 0.27.

The current collecting element preferably has a width of from approximately 1 millimeter to approximately 5 millimeters.

The current collecting element may typically have a thickness of about 0.01 millimeters to about 2 millimeters, such as about 0.5 millimeters to about 2 millimeters. The current collecting element may have a thickness of about 10 micrometers to about 500 micrometers, more preferably about 10 micrometers to about 100 micrometers.

If the current collecting element has a constant cross-section, for example a circular cross-section, it has a preferred width or diameter of from approximately 1 millimeter to approximately 5 millimeters.

If the current collecting element has the form of a strip or plate, the strip or plate preferably has a rectangular shape with a width of preferably from about 2 millimeters to about 8 millimeters, more preferably from about 3 millimeters to about 5 millimeters. As an example, the current collecting element in the form of a strip of plate can have a width of about 4 millimeters.

If the current collecting element has the form of a strip or plate, the strip or plate preferably has a rectangular shape and a thickness of about 0.03 millimeters to about 0.15 millimeters, more preferably from about 0.05 millimeters to about 0.09 millimeters. As an example, the current collecting element in the form of a strip or plate may have a thickness of about 0.07 millimeters.

In a preferred embodiment, the elongated strip or plate-shaped current collecting element is preferably rectangular in shape and has a thickness of from about 55 micrometers to about 65 micrometers.

More preferably, the elongated current collecting element has a thickness of about 57 micrometers to about 63 micrometers. Even more preferably, the elongated current collecting element has a thickness of about 58 micrometers to about 62 micrometers. In a particularly preferred embodiment, the elongated current collecting element has a thickness of about 60 micrometers.

Preferably, the elongated current-collecting element has a length that is equal to or less than the length of the aerosol-generating substrate. Preferably, the elongated current-collecting element has the same length as the aerosol-generating substrate.

The current collecting element may be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from an aerosol generating substrate. Preferred current collecting elements comprise metal or carbon.

A preferred current collector may comprise or consist of a ferromagnetic material, such as a ferromagnetic alloy, ferritic iron, or ferromagnetic steel, or stainless steel. A suitable current collector may be made of or comprise aluminum. Preferred current collectors may be formed from 400 series stainless steels, such as 410 series stainless steel, or 420 series stainless steel, or 430 series stainless steel. Different materials will dissipate different amounts of energy when they are located within electromagnetic fields having similar frequency and field strength values.

Thus, all parameters of the current collecting element, such as the type of material, length, width and thickness, can be changed to provide the desired power dissipation within a known electromagnetic field. Preferred current collecting elements can be heated to temperatures in excess of 250 degrees Celsius.

Suitable current-collecting elements may comprise a non-metallic core with a metal layer located on the non-metallic core, for example with metal tracks formed on the surface of a ceramic core. The current-collecting element may have a protective outer layer, for example a protective ceramic layer or a protective glass layer, covering the current-collecting element. The current-collecting element may comprise a protective coating formed from glass, ceramic or inert metal, formed over the core material of the current-collecting element.

The current-receiving element is arranged in thermal contact with the aerosol-generating substrate. Thus, when the current-receiving element is heated, the aerosol-generating substrate is heated and an aerosol is formed. Preferably, the current-receiving element is arranged in direct physical contact with the aerosol-generating substrate, for example, inside the aerosol-generating substrate.

The current collecting element may be a current collecting element consisting of several materials, and may comprise a first current collecting element material and a second current collecting element material. The first current collecting element material is located in direct physical contact with the second current collecting element material. The second current collecting element material preferably has a Curie temperature that is lower than 500 degrees Celsius. The first current collecting element material is preferably used mainly for heating the current collecting element when the current collecting element is placed in a fluctuating electromagnetic field. Any suitable material may be used. For example, the first current collecting element material may be aluminum or may be a ferrous metal, such as stainless steel. The second current collecting element material is preferably used mainly for indicating that the current collecting element has reached a specific temperature, wherein this temperature is the Curie temperature of the second current collecting element material. The Curie temperature of the second current-collecting element material can be used to control the temperature of the entire current-collecting element during operation. Thus, the Curie temperature of the second current-collecting element material should be below the ignition point of the aerosol-generating substrate. Suitable materials for the second current-collecting element material may include nickel and certain nickel alloys.

By providing a current-receiving element having at least a first and a second current-receiving element material, wherein either the second current-receiving element material has a Curie temperature and the first current-receiving element material does not have a Curie temperature, or the first and second current-receiving element materials have a first and a second Curie temperature different from each other, it is possible to separate the heating of the aerosol-generating substrate and to regulate the heating temperature. The first current-receiving element material is preferably a magnetic material having a Curie temperature that is higher than 500 degrees Celsius. From the viewpoint of heating efficiency, it is desirable that the Curie temperature of the first current-receiving element material exceeds any maximum temperature to which the current-receiving element should be able to be heated. The second Curie temperature can be preferably selected so as to be lower than 400 degrees Celsius, preferably lower than 380 degrees Celsius or lower than 360 degrees Celsius. Preferably, the second material of the current-receiving element is a magnetic material selected in such a way that it has a second Curie temperature that substantially coincides with the desired maximum heating temperature. That is, it is preferable that the second Curie temperature is approximately the same as the temperature to which the current-receiving element must be heated in order to generate an aerosol from the aerosol-generating substrate. The second Curie temperature can, for example, be within the range of 200 degrees Celsius to 400 degrees Celsius or from 250 degrees Celsius to 360 degrees Celsius. The second Curie temperature of the second material of the current-receiving element can, for example, be selected such that when heated by the current-receiving element, which is at a temperature equal to the second Curie temperature, the overall average temperature of the aerosol-generating substrate does not exceed 240 degrees Celsius.

As defined above, the aerosol generating article according to the present invention comprises a rod of aerosol generating substrate. The aerosol generating substrate may be a solid aerosol generating substrate.

In certain preferred embodiments, the aerosol generating substrate comprises homogenized plant material, preferably homogenized tobacco material.

In the context of this document, the term "homogenized plant material" encompasses any plant material formed by agglomerating plant particles. For example, sheets or webs of homogenized tobacco material for aerosol-generating substrates according to the present invention may be formed by agglomerating tobacco material particles obtained by grinding, milling or grinding the plant material and optionally one or more of the lamellae of a tobacco leaf and the veins of a tobacco leaf. The homogenized plant material may be obtained by casting processes, extrusion processes, papermaking processes or any other suitable methods known in the art.

The homogenized plant material may be provided in any suitable form. For example, the homogenized plant material may be in the form of one or more sheets. In the context of this document, the term "sheet" describes a layered element having a width and a length that are substantially greater than its thickness. The homogenized plant material may be in the form of a plurality of beads or granules. The homogenized plant material may be in the form of a plurality of strands, strips or pieces. In the context of this document, the term "strand" describes an elongated element of material whose length substantially exceeds its width and thickness. The term "strand" should be considered as embracing strips, pieces and any other homogenized plant material having a similar shape. The strands of homogenized plant material may be formed from a sheet of homogenized plant material, for example, by cutting or dividing into pieces, or by other methods, for example, by an extrusion method.

The threads may be formed in situ in the aerosol-generating substrate by dividing or splitting a sheet of homogenized plant material during the formation of the aerosol-generating substrate, for example by corrugating. The threads of homogenized plant material within the aerosol-generating substrate may be separated from each other. At least some of the threads of homogenized plant material in the aerosol-generating substrate may be at least partially connected to an adjacent thread or threads along the length of the threads. For example, adjacent threads may be connected by one or more fibers. This may occur, for example, if the threads were formed by dividing a sheet of homogenized plant material during the production of the aerosol-generating substrate, as described above.

Preferably, the aerosol generating substrate is provided in the form of one or more sheets of homogenized plant material. The one or more sheets of homogenized plant material may be obtained by a casting process. The one or more sheets of homogenized plant material may be obtained by a paper manufacturing process. Each of the one or more sheets, as described herein, may individually have a thickness of from about 100 micrometers to 600 micrometers, preferably from 150 micrometers to 300 micrometers, and most preferably from 200 micrometers to 250 micrometers. The individual thickness refers to the thickness of the individual sheet, while the cumulative thickness refers to the total thickness of all sheets that make up the aerosol generating substrate. For example, if the aerosol generating substrate is formed from two separate sheets, then the combined thickness is the sum of the thicknesses of the two separate sheets or the measured thickness of the two sheets when the two sheets are stacked on top of each other in the aerosol generating substrate.

Each of the one or more sheets as described herein may individually have a grammage of from about 100 g/ ^m2 to about 300 g/ ^m2 .

Each of the one or more sheets as described herein may individually have a density of from about 0.3 g/cm³ up to approximately 1.3 g/cm³and preferably from about 0.7 g/cm³up to approximately 1.0 g/cm³.

In embodiments in which the aerosol-generating substrate comprises one or more sheets of homogenized plant material, the sheets are preferably in the form of one or more assembled sheets. In the context of this document, the term "assembled" is used to describe a sheet of homogenized plant material that is rolled, bent, or otherwise compressed or narrowed in a direction substantially transverse to the cylindrical axis of the plug or rod.

One or more sheets of homogenized plant material may be collected transversely relative to its longitudinal axis and surrounded by a wrapper to form a continuous rod or plug.

One or more sheets of homogenized plant material may advantageously be corrugated or similarly treated. As used herein, the term "corrugated" means a sheet having a plurality of substantially parallel folds or corrugations. Alternatively or in addition to corrugating, one or more sheets of homogenized plant material may be embossed, blind embossed, perforated or otherwise deformed to provide texture on one or both sides of the sheet.

Preferably, each sheet of homogenized plant material may be corrugated in such a way that they have a plurality of folds or corrugations substantially parallel to the cylindrical axis of the plug. This treatment advantageously facilitates the collection of the corrugated sheet of homogenized plant material to form the plug. Preferably, one or more sheets of homogenized plant material may be collected. It should be understood that the corrugated sheets of homogenized plant material may alternatively or additionally have a plurality of substantially parallel folds or corrugations located at an acute or obtuse angle to the cylindrical axis of the plug. The sheet may be corrugated to such an extent that the integrity of the sheet is disrupted at a plurality of parallel folds or corrugations, which causes separation of the material and leads to the formation of pieces, threads or strips of homogenized plant material.

One or more sheets of homogenized plant material can be cut into threads as mentioned above. The aerosol generating substrate can comprise a plurality of threads of homogenized plant material. The threads can be used to form a plug. Typically, the width of such threads is about 5 millimeters, or about 4 millimeters, or about 3 millimeters, or about 2 millimeters or less. The length of the threads can be greater than about 5 millimeters, from about 5 millimeters to about 15 millimeters, from about 8 millimeters to about 12 millimeters, or about 12 millimeters. Preferably, the threads have substantially the same length relative to each other. The length of the threads can be determined by a manufacturing process in which the rod is cut into shorter plugs, and the length of the threads corresponds to the length of the plug. The threads can be brittle, which can lead to breakage, especially during movement. In such cases, the length of some threads may be less than the length of the plug.

The plurality of threads preferably extend substantially longitudinally along the length of the aerosol-generating substrate aligned with the longitudinal axis. Preferably, the plurality of threads are thus aligned substantially parallel to each other.

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

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

The homogenized plant material may be a homogenized tobacco material comprising tobacco particles. Sheets of homogenized tobacco material for use in such embodiments may have a tobacco content of at least about 40 percent by weight on a dry weight basis, more preferably at least about 50 percent by weight on a dry weight basis, more preferably at least about 70 percent by weight on a dry weight basis, and most preferably at least about 90 percent by weight on a dry weight basis.

The term "tobacco particles" describes particles of any plant belonging to the genus Nicotiana . The term "tobacco particles" includes ground or powdered tobacco leaf lamellae, ground or powdered tobacco leaf stems, tobacco dust, tobacco fines, and other particulate tobacco by-products generated during the processing, handling, and shipping of tobacco. In a preferred embodiment, the tobacco particles are substantially all derived from tobacco leaf lamellae. By comparison, separated nicotine and nicotine salts are compounds derived from tobacco but are not considered tobacco particles for the purposes of the present invention and are not included in the percentage of particulate plant material.

The tobacco particles may be derived from one or more varieties of tobacco plants. Any type of tobacco may be used in the blend. Examples of types of tobacco that may be used include, but are not limited to, sun-cured tobacco, flue-cured tobacco, Burley tobacco, Maryland tobacco, Oriental tobacco, Virginia tobacco, and other specialty tobaccos.

Flue-curing is a method of drying tobacco that is especially widely used with Virginia tobaccos. During the flue-curing process, heated air is circulated through tightly packed tobacco. During the first stage, the tobacco leaves turn yellow and wilt. During the second stage, the leaf blades are completely dry. During the third stage, the leaf stems are completely dry.

Burley tobacco plays an important role in many tobacco blends. Burley tobacco has a distinctive flavor and aroma, and also has the ability to absorb large amounts of sauce.

Oriental tobacco has small leaves and pronounced aromatic qualities. However, oriental tobacco has a milder flavor than, for example, Burley tobacco. Therefore, oriental tobacco is essentially used in relatively small proportions in tobacco blends.

Kasturi, Maduro and Yatim are the subtypes of sun-cured tobacco that may be used. Preferably, Kasturi tobacco and flue-cured tobacco may be used in a mixture to produce tobacco particles. Accordingly, the tobacco particles in the particulate plant material may comprise a mixture of Kasturi tobacco and flue-cured tobacco.

The tobacco particles may have a nicotine content of at least about 2.5 percent by weight on a dry weight basis. More preferably, the tobacco particles may have a nicotine content of at least about 3 percent, even more preferably at least about 3.2 percent, even more preferably at least about 3.5 percent, most preferably at least about 4 percent by weight on a dry weight basis.

The homogenized plant material may comprise tobacco particles in combination with non-tobacco plant flavor particles. Preferably, the non-tobacco plant flavor particles are selected from one or more of: ginger particles, rosemary particles, eucalyptus particles, clove particles, and star anise particles. Preferably, in such embodiments, the homogenized plant material comprises at least about 2.5 percent by weight of non-tobacco plant flavor particles on a dry weight basis, with the remainder of the plant particles being tobacco particles. Preferably, the homogenized plant material comprises at least about 4 percent by weight of non-tobacco plant flavor particles, more preferably at least about 6 percent by weight of non-tobacco plant flavor particles, more preferably at least about 8 percent by weight of non-tobacco plant flavor particles, and more preferably at least about 10 percent by weight of non-tobacco plant flavor particles, based on dry weight. Preferably, the homogenized plant material comprises up to about 20 percent by weight of non-tobacco plant flavor particles, more preferably up to about 18 percent by weight of non-tobacco plant flavor particles, more preferably up to about 16 percent by weight of non-tobacco plant flavor particles.

The weight ratio of the non-tobacco plant flavouring particles to the tobacco particles in the particulate plant material forming the homogenised plant material may vary depending on the desired flavour characteristics and the composition of the aerosol obtained from the aerosol generating substrate during use. Preferably, the homogenised plant material comprises at least a weight ratio of 1:30 of the non-tobacco plant flavouring particles to the tobacco particles, more preferably at least a weight ratio of 1:20 of the non-tobacco plant flavouring particles to the tobacco particles, more preferably at least a weight ratio of 1:10 of the non-tobacco plant flavouring particles to the tobacco particles, and most preferably at least a weight ratio of 1:5 of the non-tobacco plant flavouring particles to the tobacco particles, based on dry weight.

Homogenized plant material may contain hemp particles. The term "hemp particles" refers to particles of the hemp plant, such as the species Cannabis sativa, Cannabis indica , and Cannabis ruderalis .

The homogenized plant material preferably comprises no more than 95 percent by weight 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.

The homogenized plant material may further comprise a binder for changing the mechanical properties of the particulate plant material, wherein the binder is incorporated into the homogenized plant material during manufacture as described herein. Suitable exogenous binders are known to those skilled in the art and include, but are not limited to: gums such as, for example, guar gum, xanthan gum, acacia and locust bean gum; cellulose binders such as, for example, hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose and ethyl cellulose; polysaccharides such as, for example, starches, organic acids such as alginic acid, salts of conjugate bases with organic acids such as sodium alginate, agar and pectins; and combinations thereof. Preferably, the binder comprises guar gum.

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

The homogenized plant material may further comprise one or more lipids that promote the diffusion of volatile components (e.g., aerosol forming agents, gingerols, and nicotine), wherein the lipid is included in the homogenized plant material during manufacture as described herein. Lipids suitable for inclusion in the homogenized plant material include, but are not limited to: medium chain triglycerides, cocoa butter, palm oil, palm kernel oil, mango butter, shea butter, soybean oil, cottonseed oil, coconut oil, hydrogenated coconut oil, candelilla wax, carnauba wax, shellac, sunflower wax, sunflower oil, rice bran wax, and Revel A; and combinations thereof.

The homogenized plant material may additionally contain a pH modifier.

The homogenized plant material may further comprise fibers for altering the mechanical properties of the homogenized plant material, wherein the fibers are incorporated into the homogenized plant material during manufacture as described herein. Suitable exogenous fibers for inclusion in the homogenized plant material are known in the art and include fibers derived from non-tobacco material and non-ginger material, including but not limited to: cellulose fibers; softwood fibers; hardwood fibers; jute fibers, and combinations thereof. 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. Prior to incorporation into the homogenized plant material, the fibers may be processed by suitable processes known in the art, including but not limited to: mechanical pulping; cleaning; chemical pulping; bleaching; sulfate transformation and their combinations. The fiber is usually longer than its width.

Suitable fibers typically have lengths greater than 400 micrometers and less than or equal to 4 millimeters, preferably in the range of 0.7 millimeters to 4 millimeters. Preferably, the fibers are present in an amount of from about 2 percent to about 15 percent by weight, most preferably at a level of about 4 percent by weight, based on the dry weight of the substrate.

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

The homogenized plant material may have an aerosol forming agent content of from about 5 percent to about 30 percent by weight on a dry weight basis, such as from about 10 percent to about 25 percent by weight on a dry weight basis or from about 15 percent to about 20 percent by weight on a dry weight basis.

For example, if the substrate is intended for use in an aerosol-generating article for an electrical aerosol-generating system having a heating element, it may preferably comprise an aerosol-forming substance content of from about 5 percent to about 30 percent by weight on a dry weight basis. If the substrate is intended for use in an aerosol-generating article for an electrical aerosol-generating system having a heating element, the aerosol-forming substance is preferably glycerol.

The homogenized plant material may have an aerosol forming agent content of from about 1 percent to about 5 percent 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 agent is retained in a reservoir separate from the substrate, the substrate may have an aerosol forming agent content of greater than 1 percent and less than about 5 percent. In such embodiments, the aerosol forming agent is vaporized upon heating, and a stream of the aerosol forming agent contacts the aerosol-generating substrate to capture flavoring substances from the aerosol-generating substrate in the aerosol.

The homogenized plant material may have an aerosol forming agent content of from about 30 percent by weight to about 45 percent by weight. This relatively high level of aerosol forming agent is particularly suitable for aerosol generating substrates that are intended to be heated at a temperature of less than 275 degrees Celsius. In such embodiments, the homogenized plant material preferably further comprises from about 2 percent by weight to about 10 percent by weight of a cellulose ether on a dry weight basis and from about 5 percent by weight to about 50 percent by weight of additional cellulose on a dry weight basis. It has been found that the use of a combination of a cellulose ether and additional cellulose provides particularly effective aerosol delivery when used in an aerosol generating substrate having an aerosol forming agent content of from 30 percent by weight to 45 percent by weight.

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

In the context of this document, the term "additional cellulose" encompasses any cellulose material incorporated into the homogenized plant material that is not derived from non-tobacco plant particles or tobacco particles provided in the homogenized plant material. Accordingly, the additional cellulose is incorporated into the homogenized plant material in addition to the non-tobacco plant material or tobacco material as a cellulose source separate and distinct from any cellulose substantially provided in the non-tobacco plant particles or tobacco particles. The additional cellulose is typically derived from a plant other than the non-tobacco plant particles or tobacco particles. Preferably, the additional cellulose is in the form of an inert cellulose material that is inert to the senses and therefore does not significantly affect the organoleptic characteristics of the aerosol generated from the aerosol generating substrate. For example, the additional cellulose is preferably a tasteless and odorless material.

Supplementary cellulose may contain cellulose powder, cellulose fibers, or a combination of both.

The aerosol forming agent can act as a humectant in the aerosol generating substrate.

The wrapper surrounding the rod of homogenized plant material may be a paper wrapper or a non-paper wrapper. Paper wrappers suitable for use in certain embodiments of the present invention are known in the art and include, but are not limited to: cigarette papers and filter wicks. Non-paper wrappers suitable for use in certain embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco materials. In certain preferred embodiments, the wrapper may be formed from a laminated material comprising a plurality of layers. Preferably, the wrapper is formed from an aluminum multilayer sheet. The use of a multilayer sheet comprising aluminum advantageously prevents combustion of the aerosol-generating substrate in the event that the aerosol-generating substrate is ignited instead of heated in the intended manner.

In some preferred embodiments, the aerosol-generating substrate comprises a gel composition that comprises an alkaloid compound or a cannabinoid compound, or both an alkaloid compound and a cannabinoid compound. In particularly preferred embodiments, the aerosol-generating substrate comprises a gel composition that comprises nicotine.

Preferably, the gel composition comprises an alkaloid compound or a cannabinoid compound, or both an alkaloid compound and a cannabinoid compound; an aerosol forming agent; and at least one gelling agent. Preferably, the at least one gelling agent forms a solid medium, and glycerol is distributed in the solid medium, wherein the alkaloid or cannabinoid is distributed in the glycerol. Preferably, the gel composition is a stable gel phase.

Advantageously, a stable gel composition containing nicotine provides a predictable shape of the composition during storage or transportation from production to the consumer. A stable gel composition containing nicotine essentially maintains its shape. A stable gel composition containing nicotine essentially does not release a liquid phase during storage or transportation from production to the consumer. A stable gel composition containing nicotine can provide a simple consumable design. This consumable material can be designed without liquid content, thus a wider range of container materials and designs can be envisaged.

The gel composition described herein may be combined with an aerosol generating device to deliver a nicotine aerosol to the lungs at inhalation or air flow rates that are within the inhalation or air flow rates of a typical smoking regimen. The aerosol generating device may continuously heat the gel composition. The user may take multiple inhalations or "puffs," where each "puff" delivers a certain amount of nicotine aerosol. The gel composition may be capable of delivering a high nicotine/low total particulate matter (TPM) aerosol to the user upon heating, preferably in a continuous manner.

The phrase "stable gel phase" or "stable gel" refers to a gel that substantially maintains its shape and mass when exposed to various environmental conditions. A stable gel may not substantially release (release moisture) or absorb water when exposed to standard temperature and pressure when the relative humidity changes from about 10 percent to about 60 percent. For example, a stable gel may substantially maintain its shape and mass when exposed to standard temperature and pressure when the relative humidity changes from about 10 percent to about 60 percent.

The gel composition may contain an alkaloid compound or a cannabinoid compound, or both an alkaloid compound and a cannabinoid compound. The gel composition may contain one or more alkaloids. The gel composition may contain one or more cannabinoids. The gel composition may contain a combination of one or more alkaloids and one or more cannabinoids.

The term "alkaloid compound" refers to any of a class of naturally occurring organic compounds that contain one or more basic nitrogen atoms. Typically, an alkaloid contains at least one nitrogen atom in an amine-type structure. This or another nitrogen atom in the alkaloid compound molecule may be active as a base in acid-base reactions. Most alkaloid compounds have one or more nitrogen atoms as part of a cyclic system, such as, for example, a heterocyclic ring. In nature, alkaloid compounds are found primarily in plants and are especially common in certain families of flowering plants. However, some alkaloid compounds are found in animal and fungal species. As used herein, the term "alkaloid compound" refers to both naturally occurring alkaloid compounds and synthetically produced alkaloid compounds.

The gel composition may preferably contain an alkaloid compound selected from the group consisting of nicotine, anatabine and combinations thereof.

Preferably, the gel composition contains nicotine.

The term "nicotine" refers to nicotine and nicotine derivatives such as pure nicotine, nicotine salts, etc.

The term "cannabinoid compound" refers to any of a class of naturally occurring compounds found in parts of the cannabis plant, namely the species Cannabis sativa , Cannabis indica , and Cannabis ruderalis . Cannabinoid compounds are particularly concentrated in the female flower heads. Cannabinoid compounds naturally occurring in the cannabis plant include cannabidiol (CBD) and tetrahydrocannabinol (THC). As used herein, the term "cannabinoid compounds" is used to describe both naturally occurring cannabinoid compounds and synthetically produced cannabinoid compounds.

The gel may comprise a cannabinoid compound selected from the group consisting of cannabidiol (CBD), tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), cannabidiolic acid (CBDA), cannabinol (CBN), cannabigerol (CBG), cannabichromene (CBC), cannabicyclol (CBL), cannabivarin (CBV), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), cannabichromevarin (CBCV), cannabigerovarin (CBGV), cannabigerol monomethyl ether (CBGM), cannabielsoin (CBE), cannabicitran (CBT), and combinations thereof.

The gel composition may preferably comprise a cannabinoid compound selected from the group consisting of cannabidiol (CBD), THC (tetrahydrocannabinol), and combinations thereof.

The gel may preferably contain cannabidiol (CBD).

The gel composition may contain nicotine and cannabidiol (CBD).

The gel composition may contain nicotine, cannabidiol (CBD) and THC (tetrahydrocannabinol).

The gel composition preferably comprises from about 0.5 percent by weight to about 10 percent by weight of an alkaloid compound, or from about 0.5 percent by weight to about 10 percent by weight of a cannabinoid compound, or both the alkaloid compound and the cannabinoid compound in a total amount of from about 0.5 percent by weight to about 10 percent by weight. The gel composition can comprise from about 0.5 percent by weight to about 5 percent by weight of an alkaloid compound, or from about 0.5 percent by weight to about 5 percent by weight of a cannabinoid compound, or both the alkaloid compound and the cannabinoid compound in a total amount of from about 0.5 percent by weight to about 5 percent by weight. Preferably, the gel composition comprises from about 1 percent by weight to about 3 percent by weight of an alkaloid compound, or from about 1 percent by weight to about 3 percent by weight of a cannabinoid compound, or both the alkaloid compound and the cannabinoid compound in a total amount of from about 1 percent by weight to about 3 percent by weight. The gel composition may preferably comprise from about 1.5 percent by weight to about 2.5 percent by weight of an alkaloid compound, or from about 1.5 percent by weight to about 2.5 percent by weight of a cannabinoid compound, or both the alkaloid compound and the cannabinoid compound in a total amount of from about 1.5 percent by weight to about 2.5 percent by weight. The gel composition may preferably contain about 2 percent by weight of an alkaloid compound, or about 2 percent by weight of a cannabinoid compound, or both the alkaloid compound and the cannabinoid compound in a total amount of about 2 percent by weight. The alkaloid compound component of the gel composition may be the most volatile component of the gel composition. In some aspects, water may be the most volatile component of the gel composition, and the alkaloid compound component of the gel composition may be the second most volatile component of the gel composition. The cannabinoid compound component of the gel composition may be the most volatile component of the gel composition. In some aspects, water may be the most volatile component of the gel composition, and the alkaloid compound component of the gel composition may be the second most volatile component of the gel composition.

Preferably, nicotine is contained in gel compositions. Nicotine can be added to the composition as a free base or as a salt. The gel composition contains from about 0.5 percent by weight to about 10 percent by weight nicotine, or from about 0.5 percent by weight to about 5 percent by weight nicotine. Preferably, the gel composition contains from about 1 percent by weight to about 3 percent by weight nicotine, or from about 1.5 percent by weight to about 2.5 percent by weight nicotine, or about 2 percent by weight nicotine. The nicotine component of the gel composition may be the most volatile component of the gel composition. In some aspects, water may be the most volatile component of the gel composition, and the nicotine component of the gel composition may be the second most volatile component of the gel composition.

The gel composition preferably comprises an aerosol former. Ideally, the aerosol former is substantially resistant to thermal decomposition at the operating temperature of the associated aerosol generating device. Suitable aerosol formers include, but are not limited to: polyhydric alcohols such as triethylene glycol, 1,3-butanediol and glycerol; esters of polyhydric alcohols such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate. The polyhydric alcohols or mixtures thereof may be one or more of the following: triethylene glycol, 1,3-butanediol and glycerol (glycerol or propane-1,2,3-triol) or polyethylene glycol. The aerosol former is preferably glycerol.

The gel composition may contain a major portion of an aerosol former. The gel composition may contain a mixture of water and an aerosol former, wherein the aerosol former forms a major portion (by weight) of the gel composition. The aerosol former may form at least about 50 percent by weight of the gel composition. The aerosol former may form at least about 60 percent by weight, or at least about 65 percent by weight, or at least about 70 percent by weight of the gel composition. The aerosol former may form from about 70 percent by weight to about 80 percent by weight of the gel composition. The aerosol former may form from about 70 percent by weight to about 75 percent by weight of the gel composition.

The gel composition may contain a majority of glycerol. The gel composition may contain a mixture of water and glycerol, wherein glycerol forms a majority (by weight) of the gel composition. Glycerol may form at least about 50 percent by weight of the gel composition. Glycerol may form at least about 60 percent by weight, or at least about 65 percent by weight, or at least about 70 percent by weight of the gel composition. Glycerol may form from about 70 percent by weight to about 80 percent by weight of the gel composition. Glycerol may form from about 70 percent by weight to about 75 percent by weight of the gel composition.

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

The term "gelling agent" refers to a compound that, when uniformly added to a 50 percent by weight water/50 percent by weight glycerol mixture in an amount of approximately 0.3 percent by weight, forms a solid medium or support matrix that results in the formation of a gel. Gelling agents include, but are not limited to, hydrogen-bonding gelling agents and ionic-bonding gelling agents.

The gelling agent may include one or more biopolymers. The biopolymers may be formed from polysaccharides.

Biopolymers include, for example, gellan gums (natural, low acyl gellan gum, high acyl gellan gums, with low acyl gellan gum being preferred), xanthan gum, alginates (alginic acid), agar, guar gum, etc. The composition may preferably include xanthan gum. The composition may include two biopolymers. The composition may include three biopolymers. The composition may include two biopolymers in substantially equal weights. The composition may include three biopolymers in substantially equal weights.

Preferably, the gel composition comprises at least about 0.2 percent by weight of a gelling agent that provides crosslinking through hydrogen bonds. The gel composition preferably comprises at least about 0.2 percent by weight of a gelling agent that provides crosslinking through ionic bonds. Most preferably, the gel composition comprises at least about 0.2 percent by weight of a gelling agent that provides crosslinking through hydrogen bonds and at least about 0.2 percent by weight of a gelling agent that provides crosslinking through ionic bonds. The gel composition may contain from about 0.5 percent by weight to about 3 percent by weight of a gelling agent that provides crosslinking through hydrogen bonds and from about 0.5 percent by weight to about 3 percent by weight of a gelling agent that provides crosslinking through ionic bonds, or from about 1 percent by weight to about 2 percent by weight of a gelling agent that provides crosslinking through hydrogen bonds and from about 1 percent by weight to about 2 percent by weight of a gelling agent that provides crosslinking through ionic bonds. The gelling agent that provides crosslinking through hydrogen bonds and the gelling agent that provides crosslinking through ionic bonds may be present in the gel composition in substantially equal amounts by weight.

The term "hydrogen bonding crosslinking gelling agent" refers to a gelling agent that forms non-covalent crosslinking bonds or physical crosslinking bonds through hydrogen bonding. Hydrogen bonding is a type of dipole-dipole electrostatic attraction between molecules rather than a covalent bond with a hydrogen atom. The result is an attractive force between a hydrogen atom covalently bonded to a very electronegative atom, such as an N, O, or F atom, and another very electronegative atom.

The gelling agent providing crosslinking by hydrogen bonds may comprise one or more of galactomannan, gelatin, agarose or konjac gum, or agar. The gelling agent providing crosslinking by hydrogen bonds may preferably comprise agar.

The gel composition preferably comprises a gelling agent providing crosslinking by hydrogen bonds in a range of from about 0.3 percent by weight to about 5 percent by weight. Preferably, the composition comprises a gelling agent providing crosslinking by hydrogen bonds in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the composition comprises a gelling agent providing crosslinking by hydrogen bonds in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain galactomannan in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, galactomannan may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, galactomannan may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, galactomannan may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain gelatin in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the gelatin may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the gelatin may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the gelatin may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain agarose in a range from about 0.2 percent by weight to about 5 percent by weight. Preferably, the agarose may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the agarose may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, the agarose may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain konjac gum in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, konjac gum may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, konjac gum may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, konjac gum may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain agar in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the agar may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the agar may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the agar may be in a range of from about 1 percent by weight to about 2 percent by weight.

The term "ionic crosslinking gelling agent" refers to a gelling agent that forms non-covalent crosslinking bonds or physical crosslinking bonds through the formation of ionic bonds. Ionic crosslinking involves the linking of polymer chains through non-covalent interactions. A crosslinked network is formed when multivalent molecules of opposite charges are electrostatically attracted to each other, resulting in the formation of a crosslinked polymer network.

The gelling agent providing crosslinking by ionic bonds may comprise low acyl gellan, pectin, kappa carrageenan, iota carrageenan or alginate. The gelling agent providing crosslinking by ionic bonds may preferably comprise low acyl gellan.

The gel composition may contain a gelling agent providing crosslinking through ionic bonds in a range from about 0.3 percent by weight to about 5 percent by weight. Preferably, the composition contains a gelling agent providing crosslinking through ionic bonds in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the composition contains a gelling agent providing crosslinking through ionic bonds in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may comprise gellan with a low acyl content in the range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the gellan with a low acyl content may be in the range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the gellan with a low acyl content may be in the range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the gellan with a low acyl content may be in the range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain pectin in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the pectin may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the pectin may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the pectin may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain kappa carrageenan in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, kappa carrageenan may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, kappa carrageenan may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, kappa carrageenan may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain iota-carrageenan in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, iota-carrageenan may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, iota-carrageenan may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, iota-carrageenan may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain alginate in a range from about 0.2 percent by weight to about 5 percent by weight. Preferably, the alginate may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the alginate may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, the alginate may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may comprise a gelling agent providing crosslinking by means of hydrogen bonds and a gelling agent providing crosslinking by means of ionic bonds in a ratio of about 3:1 to about 1:3. Preferably, the gel composition may comprise a gelling agent providing crosslinking by means of hydrogen bonds and a gelling agent providing crosslinking by means of ionic bonds in a ratio of about 2:1 to about 1:2. Preferably, the gel composition may comprise a gelling agent providing crosslinking by means of hydrogen bonds and a gelling agent providing crosslinking by means of ionic bonds in a ratio of about 1:1.

The gel composition may further comprise a viscosity increasing agent. The viscosity increasing agent in combination with a gelling agent providing crosslinking by hydrogen bonds and a gelling agent providing crosslinking by ionic bonds appears to unexpectedly maintain a solid environment and preserve the gel composition even if the gel composition contains a high level of glycerol.

The term "viscosity increasing agent" refers to a compound which, when uniformly added to a 50 percent by weight water/50 percent by weight glycerol mixture at 25 degrees Celsius in an amount of 0.3 percent by weight, increases the viscosity without causing gel formation, while the mixture remains or remains liquid. Preferably, the viscosity increasing agent refers to a compound which, when uniformly added to a 50 percent by weight water/50 percent by weight glycerol mixture at 25 degrees Celsius in an amount of 0.3 percent by weight, increases the viscosity to at least 50 cP, preferably at least 200 cP, preferably at least 500 cP, preferably at least 1000 cP at a shear rate of 0.1 s ^-1 , without causing gel formation, while the mixture remains or remains liquid. Preferably, the viscosity increasing agent is a compound which, when uniformly added to a 50 percent by weight water/50 percent by weight glycerol mixture at 25 degrees Celsius in an amount of 0.3 percent by weight, increases the viscosity by at least 2 times, or at least 5 times, or at least 10 times, or at least 100 times than before addition, at a shear rate of 0.1 s ^-1 , without causing gel formation, while the mixture remains or remains liquid.

The viscosity values given in this document can be measured using a Brookfield RVT viscometer rotating an RV#2 disc type shaft at 25 degrees Celsius at 6 revolutions per minute (rpm).

The gel composition preferably comprises a viscosity increasing agent in the range of about 0.2 percent by weight to about 5 percent by weight. Preferably, the composition comprises a viscosity increasing agent in the range of about 0.5 percent by weight to about 3 percent by weight. Preferably, the composition comprises a viscosity increasing agent in the range of about 0.5 percent by weight to about 2 percent by weight. Preferably, the composition comprises a viscosity increasing agent in the range of about 1 percent by weight to about 2 percent by weight.

The viscosity increasing agent may comprise one or more of xanthan gum, carboxymethyl cellulose, microcrystalline cellulose, methyl cellulose, acacia, guar gum, lambda carrageenan or starch. The viscosity increasing agent may preferably comprise xanthan gum.

The gel composition may contain xanthan gum in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the xanthan gum may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the xanthan gum may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the xanthan gum may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain carboxymethylcellulose in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the carboxymethylcellulose may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the carboxymethylcellulose may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the carboxymethylcellulose may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain microcrystalline cellulose in a range from about 0.2 percent by weight to about 5 percent by weight. Preferably, the microcrystalline cellulose may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the microcrystalline cellulose may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, the microcrystalline cellulose may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain methylcellulose in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, the methylcellulose may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, the methylcellulose may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, the methylcellulose may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain acacia in a range of about 0.2 percent by weight to about 5 percent by weight. Preferably, the acacia may be in a range of about 0.5 percent by weight to about 3 percent by weight. Preferably, the acacia may be in a range of about 0.5 percent by weight to about 2 percent by weight. Preferably, the acacia may be in a range of about 1 percent by weight to about 2 percent by weight.

The gel composition may contain guar gum in a range from about 0.2 percent by weight to about 5 percent by weight. Preferably, guar gum may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, guar gum may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, guar gum may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain lambda carrageenan in a range of from about 0.2 percent by weight to about 5 percent by weight. Preferably, lambda carrageenan may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, lambda carrageenan may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, lambda carrageenan may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain starch in a range from about 0.2 percent by weight to about 5 percent by weight. Preferably, the starch may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the starch may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, the starch may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may further comprise a divalent cation. Preferably, the divalent cation comprises calcium ions, such as calcium lactate in solution. Divalent cations (such as calcium ions) may promote gelation of compositions that contain gelling agents, such as, for example, a gelling agent that provides crosslinking through ionic bonds. The ionic effect may promote gelation. The divalent cation may be present in the gel composition in a range of about 0.1 to about 1 percent by weight, or in an amount of about 0.5 percent by weight.

The gel composition may further comprise an acid. The acid may comprise a carboxylic acid. The carboxylic acid may comprise a ketone group. Preferably, the carboxylic acid may comprise a ketone group having less than about 10 carbon atoms, or less than about 6 carbon atoms, or less than about 4 carbon atoms, such as levulinic acid or lactic acid. Preferably, this carboxylic acid has three carbon atoms (e.g., lactic acid). Lactic acid unexpectedly improves the stability of the gel composition even compared to similar carboxylic acids. The carboxylic acid may promote gelation. The carboxylic acid may reduce the change in the concentration of the alkaloid compound, or the concentration of the cannabinoid compound, or the concentration of both the alkaloid compound and the cannabinoid compound within the gel composition during storage. The carboxylic acid may reduce the change in the concentration of nicotine within the gel composition during storage.

The gel composition may contain a carboxylic acid in a range from about 0.1 percent by weight to about 5 percent by weight. Preferably, the carboxylic acid may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the carboxylic acid may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, the carboxylic acid may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain lactic acid in a range from about 0.1 percent by weight to about 5 percent by weight. Preferably, the lactic acid may be in a range from about 0.5 percent by weight to about 3 percent by weight. Preferably, the lactic acid may be in a range from about 0.5 percent by weight to about 2 percent by weight. Preferably, the lactic acid may be in a range from about 1 percent by weight to about 2 percent by weight.

The gel composition may contain levulinic acid in a range of from about 0.1 percent by weight to about 5 percent by weight. Preferably, levulinic acid may be in a range of from about 0.5 percent by weight to about 3 percent by weight. Preferably, levulinic acid may be in a range of from about 0.5 percent by weight to about 2 percent by weight. Preferably, levulinic acid may be in a range of from about 1 percent by weight to about 2 percent by weight.

The gel composition preferably contains some water. The gel composition is more stable if the composition contains some water. Preferably, the gel composition contains at least about 1 percent by weight, or at least about 2 percent by weight, or at least about 5 percent by weight of water. Preferably, the gel composition contains at least about 10 percent by weight, or at least about 15 percent by weight of water.

Preferably, the gel composition comprises from about 8 percent by weight to about 32 percent by weight of water. Preferably, the gel composition comprises from about 15 percent by weight to about 25 percent by weight of water. Preferably, the gel composition comprises from about 18 percent by weight to about 22 percent by weight of water. Preferably, the gel composition comprises about 20 percent by weight of water.

Preferably, the aerosol generating substrate comprises from about 150 mg to about 350 mg of the gel composition.

Preferably, in embodiments comprising a gel composition, the aerosol generating substrate comprises a porous medium filled with a gel composition. The advantages of a porous medium filled with a gel composition are that the gel composition is retained within the porous medium, and this can facilitate the manufacture, storage or transportation of the gel composition. This can help maintain the desired shape of the gel composition, especially during manufacture, transportation or use.

The term "porous" is used in this document to refer to a material that provides multiple pores or openings that allow air to pass through the material.

The porous medium may be any suitable porous material capable of holding or retaining the gel composition. Ideally, the porous medium may allow the gel composition to move within it. In particular embodiments, the porous medium comprises natural materials, synthetic or semi-synthetic materials, or a combination thereof. In particular embodiments, the porous medium comprises a sheet material, a foam material, or fibers, such as loose fibers, or a combination thereof. In particular embodiments, the porous medium comprises a woven, non-woven or extruded material, or combinations thereof. Preferably, the porous medium comprises cotton, paper, viscose, PLA, or cellulose acetate, or combinations thereof. Preferably, the porous medium comprises a sheet material, such as cotton or cellulose acetate. In a particularly preferred embodiment, the porous medium comprises a sheet made of cotton fibers.

The porous medium may be corrugated or split. In preferred embodiments, the porous medium is corrugated. In alternative embodiments, the porous medium comprises a split porous medium. The corrugation or splitting process may be performed before or after filling with the gel composition.

Corrugation of the sheet material has the advantage of improving the structure to provide passages through the structure. The passages through the corrugated sheet material assist in filling the gel, retaining the gel, and also for the fluid to pass through the corrugated sheet material. Therefore, there are advantages to using the corrugated sheet material as a porous medium.

The splitting provides a high surface area to volume ratio for the medium, which is thus able to easily absorb the gel.

In some embodiments, the sheet material is a composite material. Preferably, the sheet material is porous. The sheet material can facilitate the production of a tubular element containing a gel. The sheet material can facilitate the introduction of an active substance into the tubular element containing a gel. The sheet material can help stabilize the structure of the tubular element containing a gel. The sheet material can facilitate the transportation or storage of the gel. The use of the sheet material allows or provides the addition of structure to a porous medium, for example, by corrugating the sheet material.

The porous medium may be a thread. The thread may contain, for example, cotton, paper or acetate rod. The thread may also be filled with a gel, like any other porous medium. The advantage of using a thread as a porous medium is that it can facilitate easy fabrication.

The thread may be filled with gel by any known means. The thread may simply be coated with gel, or the thread may be impregnated with gel. During manufacture, the threads may be impregnated with gel and stored ready for use in the assembly of a tubular element.

Preferably, in embodiments where the first element comprises a gel composition as described above, the downstream section of the aerosol-generating article comprises a first tubular element according to the present invention, wherein the first tubular element has a length of less than 10 millimeters. The use of such a relatively short tubular element in combination with the gel composition can optimize the delivery of the aerosol to the consumer.

Embodiments of the present invention in which the aerosol-generating substrate comprises a gel composition as described above preferably comprise an upstream element located upstream of the first element containing the aerosol-generating substrate. In this case, the upstream element advantageously prevents physical contact with the gel composition. The upstream element can also advantageously compensate for any potential decrease in RTD, for example due to evaporation of the gel composition when the first element containing the aerosol-generating substrate is heated during use.

Features described with respect to one example or embodiment may also be applied to other examples and embodiments.

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

EX1. A tubular element for an aerosol generating article, wherein the tubular element comprises: a tubular body defining a cavity extending from a first end of the tubular body to a second end of the tubular body; a bent end portion defining a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outside of the tubular element; and a ventilation zone at a location along the tubular body of the tubular element.

EX2. A tubular element according to EX1, wherein the ventilation zone comprises a plurality of perforations in the tubular body.

EX3. A tubular element according to EX1 or EX2, in which the ventilation zone is located at a distance of from approximately 5 millimetres to approximately 15 millimetres from the bent end portion of the tubular element.

EX4. A tubular element according to any one of EX1 to EX3, wherein the ventilation zone comprises at least one annular row of perforations extending around the tubular element.

EX5. A tubular element according to any one of EX1-EX4, wherein the tubular element has a ventilation level of from about 20 percent to about 70 percent.

EX6. A tubular element according to any one of EX1 to EX5, wherein the tubular element is formed from a paper material.

EX7. A tubular element according to any one of EX1 to EX6, wherein at least the first portion of the tubular element forming the first end wall is airtight.

EX8. A tubular element according to any of EX1-EX7, wherein the first end wall partially extends into the cavity of the tubular body and forms an angle of less than 90 degrees with the inner surface of the tubular body.

EX9. An aerosol generating article, wherein the aerosol generating article comprises: a first element comprising an aerosol generating substrate; and a tubular element according to any of EX1-EX8, wherein the tubular element is located upstream or downstream of the first element.

EX10. An aerosol generating article according to EX9, wherein the tubular element is adjacent to the first element.

EX11. An aerosol generating article according to EX10, wherein the first end wall of the tubular element is adjacent to the tubular element.

EX12. An aerosol generating article according to EX11, wherein the first end wall of the tubular element is in contact with the aerosol generating substrate.

EX13. An aerosol generating article according to any of EX9-EX12, wherein the aerosol generating substrate is an aerosol generating substrate rod, and wherein the first element further comprises a current collecting element located within the aerosol generating substrate rod.

EX14. An aerosol-generating article according to EX13, wherein the current-collecting element is an elongated current collector located longitudinally within the aerosol-generating substrate.

EX15. An aerosol generating article according to any of EX9-EX14, wherein the tubular element is a first tubular element and is located downstream of the aerosol generating substrate, wherein the first end wall of the first tubular element is adjacent to the downstream end of the aerosol generating substrate.

EX16. An aerosol generating article according to EX15, wherein the ventilation zone is located in a downstream section of the first tubular element.

EX17. An aerosol generating article according to EX15 or EX16, further comprising a second tubular element, wherein the second tubular element comprises: a tubular body defining a cavity extending from a first end of the tubular body to a second end of the tubular body; and a bent end portion defining a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outside of the second tubular element, wherein the second tubular element is located upstream relative to the aerosol generating substrate, wherein the first end wall of the second tubular element is located adjacent to the upstream end of the aerosol generating substrate.

EX18. An aerosol generating article according to EX17, wherein the second tubular element further comprises a bent end portion defining a second end wall at the second end of the tubular body, wherein the second end wall defines an opening for air flow between the cavity and the outer side of the second tubular element.

EX19. An aerosol generating article according to EX18, wherein the opening defined by the second end wall of the second tubular element is smaller than the opening defined by the first end wall of the second tubular element.

EX20. An aerosol generating article according to any of EX17-EX19, wherein the second tubular member is an upstream component of the aerosol generating article.

EX21. An aerosol generating article according to any of EX15-EX20, further comprising a ventilation zone at a location along the first tubular element.

EX22. An aerosol generating article according to any of EX15-EX22, further comprising a mouthpiece element located downstream of the first tubular element.

EX23. An aerosol generating article according to EX22, wherein the mouthpiece element comprises a segment of filter material.

EX24. An aerosol generating article according to any of EX1-EX23, wherein the cavity in the tubular body is an empty cavity.

It should be understood that the features described with respect to one example or embodiment may also be applicable to other examples and embodiments. For example, it should be understood that the features that have been described so far with respect to one or more of the device, the use of the device, and the components of the device configured to perform specific functions also amount to the disclosure of methods of operation of the device. For example, the disclosure of a corrugating device configured to corrugate a strip of material also amounts to the disclosure of a step of a method for corrugating a strip of material using the corrugating device.

The present invention will now be further described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a schematic side sectional view of an aerosol generating article according to a first embodiment of the present invention;

Fig. 2 is a schematic side sectional view of an aerosol generating article according to a second embodiment of the present invention;

Fig. 3 is a schematic side sectional view of an aerosol generating article according to a third embodiment of the present invention;

Fig. 4 is a perspective view of a tubular element of an aerosol generating article according to a first embodiment of the present invention;

Fig. 5A-5D are schematic side sectional views illustrating stages in the formation of the tubular element of the aerosol generating article of Fig. 1;

Fig. 6 is a schematic side sectional view of an aerosol generating article according to a fourth embodiment of the present invention;

Fig. 7 is a schematic side sectional view of an aerosol generating article according to a fifth embodiment of the present invention; and

Fig. 8 is a schematic side sectional view of an aerosol generating article according to a sixth embodiment of the present invention.

Fig. 1 shows an aerosol generating article 1 according to a first embodiment of the present invention. The aerosol generating article 1 comprises a first element 11 comprising an aerosol generating substrate 12 and a downstream section 14 at a location downstream of the first element 11. Furthermore, the aerosol generating article 1 comprises an upstream section 16 at a location upstream of the first element 11. Thus, the aerosol generating article 1 extends from an upstream or distal end 18 to a downstream or mouth end 20.

The aerosol generating product has an overall length of approximately 45 millimetres.

The downstream section 14 comprises a tubular element 100 positioned immediately downstream of the first element 11, wherein the tubular element 100 is aligned in the longitudinal direction with the first element 11. In the embodiment of Fig. 1, the upstream end of the tubular element 100 adjoins the downstream end of the first element 11 and, in particular, the downstream end of the aerosol-generating substrate 12.

In addition, the downstream section 14 comprises a mouthpiece element 42 at a location downstream of the tubular element 100. In more detail, the mouthpiece element 42 is located immediately downstream of the tubular element 100. As shown in Fig. 1, the upstream end of the mouthpiece element 42 adjoins the downstream end 40 of the tubular element 100.

The mouthpiece element 42 is provided in the form of a cylindrical plug made of low-density cellulose acetate. The mouthpiece element 42 has a length of approximately 12 millimeters and an outer diameter of approximately 7.25 millimeters. The RTD of the mouthpiece element 42 is approximately 12 millimeters of water.

The aerosol generating article 1 comprises a ventilation zone 60 provided at a location along the tubular element 100. In more detail, the ventilation zone is provided at a distance of approximately 4 millimeters from the downstream end of the tubular element 100. The ventilation level of the aerosol generating article 10 is approximately 40 percent.

The first element 11 is made in the form of a rod containing an aerosol-generating substrate 12 of one of the types described above. The aerosol-generating substrate 12 can essentially determine the structure and dimensions of the rod 11. The rod 11 can further comprise a wrapper (not shown) surrounding the aerosol-generating substrate 12. The rod 11 containing the aerosol-generating substrate has an outer diameter of approximately 7.25 millimeters and a length of approximately 12 millimeters.

The first element 11 also comprises an elongated current-collecting element 44 inside the aerosol-generating substrate 12. In more detail, the current-collecting element 44 is arranged substantially longitudinally inside the aerosol-generating substrate 12, so that it is approximately parallel to the longitudinal direction of the rod 11. As shown in the image of Fig. 1, the current-collecting element 44 is arranged in a radially central position inside the rod and extends substantially along the longitudinal axis of the rod 11.

The current collecting element 44 extends the entire distance from the upstream end to the downstream end of the aerosol generating substrate 12. In fact, the current collecting element 44 has substantially the same length as the first element 11 containing the aerosol generating substrate 12.

In the embodiment according to Fig. 1, the current collecting element 44 is provided in the form of a strip and has a length of approximately 12 millimeters, a thickness of approximately 60 micrometers and a width of approximately 4 millimeters.

The upstream section 16 comprises an upstream element 46 arranged immediately upstream of the first element 11, wherein the upstream element 46 is aligned in the longitudinal direction with the first element 11. In the embodiment of Fig. 1, the downstream end of the upstream element 46 adjoins the upstream end of the first element 11 and, in particular, the upstream end of the aerosol-generating substrate 12. This advantageously prevents the current-collecting element 44 from shifting. In addition, this ensures that the consumer cannot accidentally touch the heated current-collecting element 44 after use.

The upstream element 46 is provided in the form of a cylindrical plug of cellulose acetate that is surrounded by a rigid wrapper. The upstream element 46 has a length of approximately 5 millimeters. The RTD of the upstream element 46 is approximately 30 millimeters of water.

The aerosol-generating article 1 further comprises an outer wrapper 109 surrounding at least the tubular element. As shown in Fig. 1, the outer wrapper also surrounds the first element 11, the mouthpiece element 42 and the upstream element 46. The outer wrapper 109 extends from the upstream or distal end 18 to the downstream or mouthpiece end 20.

The tubular element 100 comprises a tubular body 103 defining a cavity 106 extending from a first end 101 of the tubular body 103 to a second end 102 of the tubular body 103. The tubular element 100 also comprises a bent end portion defining a first end wall 104 at the first end 101 of the tubular body 103. The first end wall 104 also defines an opening 105 that provides an air flow between the cavity 106 and the outer side of the tubular element 100. In particular, the embodiment according to Fig. 1 is designed in such a way that the aerosol can pass from the first element 11 through the opening 105 into the cavity 106.

The cavity 106 of the tubular body 103 is substantially empty, and therefore a substantially unrestricted air flow is possible along the cavity 106. Therefore, the RTD of the tubular element 100 can be localized in a particular longitudinal position of the tubular element 100, namely, on the first end wall 104, and can be controlled by means of a selected configuration of the first end wall 104 and its corresponding opening 105. In the embodiment of Fig. 1, the RTD of the tubular element 100 (which is essentially the RTD of the first end wall 104) is substantially 10 millimeters of water column. In the embodiment of Fig. 1, the tubular element 100 has a length of approximately 16 millimeters, an outer diameter of approximately 7.25 millimeters and an inner diameter ( _DFTS ) of approximately 6.5 millimeters. Thus, the thickness of the peripheral wall of the tubular body 103 is approximately 0.75 millimeters.

As shown in Fig. 1, and also in more detail in the perspective view of Fig. 4, the first end wall 104 extends substantially transversely to the longitudinal direction of the aerosol generating article 1 and the longitudinal direction of the tubular element 100. The opening 105 is the only opening in the first end wall 104, and the opening 105 is generally located in the radial central position of the tubular element 100. Therefore, the first end wall 104 typically has an annular shape.

The combination of the first end wall 104 and its corresponding opening 105 provides an effective partition structure that can restrict the movement of the aerosol-generating substrate while also allowing one or both of the air and the aerosol to pass from the first element 11 and through the opening 105 into the cavity 106. The opening 105 is generally aligned with the radially central position of the current collecting element 44 of the first element 11. This can be advantageous because it helps to maintain a distance between the first end wall 105 and the current collecting element and, thus, reduces unwanted heating of the first end wall 105. This can also be advantageous because it can provide a direct, unimpeded flow of aerosol downstream created by a portion of the aerosol-generating substrate in the immediate vicinity of the current collecting element 44.

As will be described in more detail below with reference to Fig. 5A-5D, the first end wall 104 is formed by bending the end portion of the tubular element 100 around a bending point. The bending point typically corresponds to the first end of the tubular body 103 of the tubular element 100.

Fig. 2 shows an aerosol-generating article 2 according to a second embodiment of the present invention. The aerosol-generating article 2 according to the second embodiment is generally the same as the aerosol-generating article 1 according to the first embodiment, except that the aerosol-generating article 2 according to the second embodiment does not comprise an upstream element 46 provided in the form of a cylindrical plug made of cellulose acetate surrounded by a rigid wrapper. Instead, the aerosol-generating article 2 according to the second embodiment comprises a second tubular element 200 located immediately upstream of the first element 11. Therefore, in this second embodiment, the tubular element 100 located immediately downstream of the first element 11 is called the first tubular element 100.

The second tubular element 200 comprises a tubular body 203 defining a cavity 206 extending from the first end of the tubular body 203 to the second end of the tubular body 203. The tubular element 200 also comprises a bent end portion defining a first end wall 204a at the first end of the tubular body 103. The first end wall 204a defines an opening 205a that provides air flow between the cavity 206 and the outer side of the second tubular element 200. In particular, the embodiment of Fig. 2 is designed in such a way that air can pass from the cavity 206 through the opening 205a and into the first element 11.

Thus, the second tubular element 200 is similar to the first tubular element 100 in that the end portion of the tubular element 200 is bent to form an end wall 205a, which extends substantially transversely to the longitudinal direction of the aerosol-generating article and which is located adjacent to the end of the aerosol-generating substrate 12. In this case, the second tubular element 200 is located upstream, and not downstream relative to the first element 11 containing the aerosol-generating substrate 12, which means that the end wall 204a is located adjacent to the upstream end of the aerosol-generating substrate 12.

However, unlike the first tubular element, the second tubular element 200 also comprises a second end wall 204b at the second end of its tubular body 203. This second end wall 204b is formed by bending the end portion of the second tubular element 200 at the second end of the tubular body of the second tubular element 200. The second end wall 204b also defines an opening 205b, which also provides an air flow between the cavity 206 and the outer side of the second tubular element 200. In the case of the second end wall 204b, the opening 205b is designed in such a way that air can pass from the outside of the aerosol-generating article 2 through the opening 205b and into the cavity 206. Thus, the opening 205b provides a passage through which air can be drawn into the aerosol-generating article 2 and through the aerosol-generating substrate 12. In the embodiment of Fig. 2, the first end wall 204a of the second tubular element 200 may be referred to as the downstream end wall of the second tubular element 200. Similarly, the second end wall 204b of the second tubular element 200 may be referred to as the upstream end wall of the second tubular element 200.

Fig. 3 shows an aerosol generating article 3 according to a third embodiment of the present invention. The aerosol generating article 3 according to the third embodiment is generally the same as the aerosol generating article 1 according to the first embodiment, except that the aerosol generating article 3 according to the third embodiment does not contain in any form an upstream element 46 upstream of the first element 11. Therefore, the upstream or distal end 18 of the aerosol generating article 3 is defined by the first element 11. Moreover, in the third embodiment of the present invention, the first element 11 does not contain a current collecting element 44 disposed inside the aerosol generating substrate 12. Therefore, such an aerosol generating article 3 may be an article that is configured to accommodate a heater plate of an aerosol generating device. The heating plate can be inserted into the aerosol generating substrate 12 through the upstream end 18 of the aerosol generating article 3.

The tubular member 300 of the aerosol generating article 3 according to the third embodiment is substantially the same as the tubular member 100 of the aerosol generating article 1 according to the first embodiment, except that the tubular member 300 is longer than the tubular member 100.

Fig. 5A-5D show a tubular element for an aerosol generating article according to the present invention at different stages of its formation. Thus, these figures illustrate a method for forming a tubular element, such as the tubular element 100 of Fig. 1.

As illustrated in Fig. 5A, the method begins with providing a tubular element 500 comprising a first end portion 504 and a tubular body 103 adjacent to and integral with the first end portion 504. To form the first end wall 104, a bending force is applied to the tubular element 500 to bend the first end portion 504 about a bending point 501 corresponding to the first end of the tubular body 103.

The bending force deflects the first end portion 504 inwardly relative to the tubular body 103 (as indicated by the dotted curved arrows in Fig. 5A, 5B and 5C) and towards the cavity 106 of the tubular body 103. The bending force is continued to be applied until the first end portion 504 is bent at an angle greater than 90 degrees, measured relative to the walls of the tubular body 103. Such a position is shown in Fig. 5C. As can be seen in Fig. 5C, in such a position, at least a portion of the first end portion 504 of the tubular element 500 extends into the cavity 106 of the tubular body 103. In other words, at least a portion of the first end portion 504 of the tubular element 500 has a longitudinal position that is located between the position of the first end of the tubular body 103 and the position of the second end of the tubular body 103.

As soon as the first end portion 504 reaches the position according to Fig. 5C, the bending force is no longer applied. At this point, the elastic properties of the tubular element 500 inherent in the paper material (such as paper, thin cardboard or cardboard) will cause the first end portion 504 to partially return back along the path of its bending, as a result of which the first end portion 504 reaches a position in which it extends substantially across the longitudinal direction of the tubular body 103. This position is illustrated in Fig. 5D, which shows a completely formed tubular element 100. In particular, the bent first end portion 504 forms a first end wall 104 at the first end of the tubular body 103, wherein the first end wall 104 defines an opening 105 for the flow of air between the cavity 106 and the outer side of the tubular element 100.

In the design of Fig. 5A-5D, the second end of the tubular element 500 is not bent; however, it should be understood that similar method steps can be applied to this second end of the tubular element 500 in order to obtain a tubular element having two bent end portions, each of which forms respective first and second end walls for the tubular element.

Fig. 6 shows an aerosol-generating article 6 according to a fourth embodiment of the present invention. The aerosol-generating article 6 according to the fourth embodiment is generally the same as the aerosol-generating article 3 according to the third embodiment, and, where appropriate, like reference numerals are used. However, the aerosol-generating article 6 according to the fourth embodiment does not comprise a mouthpiece element 42 at a location downstream of the tubular element 600. Instead, the tubular element 600 of Fig. 6 extends the entire distance from the downstream end of the aerosol-forming substrate 12 to the mouthpiece end 20 of the aerosol-generating article 6. Thus, the downstream section 14 of the aerosol-generating article 6 of Fig. 6 is completely formed by the tubular element 600.

Moreover, in the embodiment of Fig. 6, the first end wall 604 of the tubular element 600 is not located adjacent to the downstream end of the aerosol-forming substrate 12. Instead, the first end wall 604 of the tubular element 600 is located at the mouth end 20 of the aerosol-generating article 6. The first end wall 604 also defines an opening 605 that provides air flow between the cavity 606 and the outside of the tubular element 600. The opening 605 is designed such that one or both of the air and the aerosol can pass from the cavity 606 through the opening 605b to the outside of the aerosol-generating article 6.

Fig. 7 shows an aerosol generating article 7 according to a fifth embodiment of the present invention. The aerosol generating article 7 according to the fifth embodiment is generally the same as the aerosol generating article 6 according to the fourth embodiment, and, where appropriate, like reference numerals are used. However, the aerosol generating article 7 according to the fifth embodiment now comprises a mouthpiece element in the form of a hollow tube 742 at a location downstream of the tubular element 700. Thus, the tubular element 700 of Fig. 7 extends all the way to the upstream end of this hollow tube 742. The downstream section 14 of the aerosol generating article 6 of Fig. 6 is thus formed by the tubular element 700 and the hollow tube 742.

Fig. 8 shows an aerosol generating article 8 according to a sixth embodiment of the present invention. The aerosol generating article 8 according to the sixth embodiment is generally the same as the aerosol generating article 1 according to the first embodiment, and similar reference numerals are used where appropriate.

However, in the embodiment of Fig. 8, the tubular member 800 does not contact the first member 11 containing the aerosol-generating substrate 12. Instead, between the downstream end of the first member 11 and the first end wall 804 at the upstream end 801 of the tubular member 800, there is an empty space 850. Therefore, in the embodiment of Fig. 8, the first end wall 804 of the tubular member 800 does not provide a partition that is in contact with the aerosol-generating substrate 12 to limit the movement of the aerosol-generating substrate 12. However, the empty space 850 provides an area in which any fallen particles or pieces from the aerosol-generating substrate 12 can accumulate during use of the aerosol-generating article 8. The first end wall 804 may, by means of gravity, prevent such fallen particles or pieces from further moving downstream within the aerosol generating article 8.

Claims (20)

1. An aerosol generating article comprising a plurality of elements assembled in the form of a rod and including: an element containing an aerosol generating substrate; and a tubular element located upstream or downstream of said element and comprising: - a tubular body forming a cavity extending from a first end of the tubular body to a second end of the tubular body; and - a bent end portion forming a first end wall at a first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outer side of the tubular element; wherein the aerosol generating article further comprises an outer wrapper surrounding at least the tubular element. 2. An aerosol generating article according to claim 1, wherein the tubular element is adjacent to said element. 3. An aerosol generating article according to claim 2, wherein the first end wall of the tubular element is adjacent to said element. 4. An aerosol generating article according to claim 3, wherein the first end wall of the tubular element is in contact with the aerosol generating substrate. 5. An aerosol generating article according to any one of claims 1 to 4, wherein the aerosol generating substrate is a rod of an aerosol generating substrate, wherein said element further comprises a current collecting element located inside the rod of the aerosol generating substrate. 6. An aerosol-generating article according to claim 5, wherein the current-collecting element is an elongated current collector located longitudinally within the aerosol-generating substrate. 7. An aerosol generating article according to any one of claims 1 to 6, wherein the tubular element is a first tubular element and is located downstream of the aerosol generating substrate, wherein the first end wall of the first tubular element is adjacent to the downstream end of the aerosol generating substrate. 8. The aerosol generating article of claim 7, further comprising a second tubular element comprising: a tubular body defining a cavity extending from a first end of the tubular body to a second end of the tubular body; and a bent end portion defining a first end wall at the first end of the tubular body, wherein the first end wall defines an opening for air flow between the cavity and the outside of the second tubular element, wherein the second tubular element is located upstream relative to the aerosol generating substrate, wherein the first end wall of the second tubular element is adjacent to the upstream end of the aerosol generating substrate. 9. An aerosol generating article according to claim 8, wherein the second tubular element further comprises a bent end portion forming a second end wall at the second end of the tubular body, wherein the second end wall defines an opening for air flow between the cavity and the outer side of the second tubular element. 10. An aerosol generating article according to claim 9, wherein the opening defined by the second end wall of the second tubular element is smaller than the opening defined by the first end wall of the second tubular element. 11. An aerosol generating article according to any one of claims 8 to 10, wherein the second tubular element is the upstreammost component of the aerosol generating article. 12. An aerosol generating article according to any one of paragraphs 8-11, further comprising a ventilation zone at a location along the first tubular element. 13. An aerosol generating article according to any one of paragraphs 8-12, further comprising a mouthpiece element located downstream of the first tubular element. 14. An aerosol generating article according to any one of paragraphs. 8-13, in which the ventilation zone is located in a downstream section of the first tubular element. 15. An aerosol generating article according to any one of paragraphs 1-14, in which the first end wall of the tubular element partially extends into the cavity of the tubular body and forms an angle of less than 90 degrees with the inner surface of the tubular body.