AEROSOL-GENERATING PRODUCT CONTAINING A MULTIPLE AEROSOL-GENERATING ELEMENTS

Abstract

There is provided an aerosol-generating article (100). The aerosol-generating article (100) comprises a downstream section (101). The downstream section (101) comprises a downstream plug (102). The aerosol-generating article (100) comprises an upstream section (105). The upstream section (105) comprises an upstream plug (106). The upstream section (105) is spaced apart from the downstream section (101). The upstream section (105) is located upstream of the downstream section (101). The aerosol-generating article (100) comprises a substrate compartment (108) between the downstream section (101) and the upstream section (105). The substrate compartment (108) comprises a plurality of aerosol-generating elements (109). The plurality of aerosol-generating elements (109) comprise a carrier medium. An aerosol-generating substrate is sorbed in the carrier medium. The downstream section (101) and the upstream section (105) are configured to retain the aerosol-generating elements (109) between the downstream section (101) and the upstream section (105). The upstream section (105) defines an upstream end (107) of the aerosol-generating article (100). The upstream section (105) does not comprise an aerosol-generating substrate. The upstream plug (106) has a length of greater than or equal to 2 millimetres.

Description

[0001] AN AEROSOL-GENERATING ARTICLE COMPRISING A PLURALITY OF AEROSOLGENERATING ELEMENTS

[0002] The present disclosure relates to an aerosol-generating article comprising a plurality of aerosol-generating elements. The present disclosure also relates to an aerosol-generating system comprising the aerosol-generating article and an aerosol-generating device configured to heat the aerosol-generating article.

[0003] Aerosol-generating articles in which an aerosol-generating substrate, such as a tobacco containing substrate, is heated rather than combusted are known in the art. In heated aerosolgenerating articles, the aerosol is generated by heating the aerosol-generating substrate.

[0004] It is known to provide a heating element for heating an aerosol-generating substrate of an aerosol-generating article. The heating element may be provided in the article in the form of a susceptor element, which is capable of being heated when penetrated by a varying magnetic field. Alternatively or additionally, the heating element may be provided in an aerosol-generating device for generating an inhalable vapor. Such a device may heat the aerosol-generating substrate contained in the aerosol-generating article without burning the aerosol-generating substrate.

[0005] Handheld electrically operated aerosol-generating systems comprising a cartridge comprising a storage portion containing a supply of liquid aerosol-generating substrate and an electrically operated heater configured to heat the liquid aerosol-generating substrate to generate an inhalable aerosol are also known. Such known handheld electrically operated aerosolgenerating systems comprise an aerosol-generating device comprising control circuitry and a power source for supplying power to the electrically operated heater. The electrically operated heater typically comprises a coil of electrically conductive wire that is wound around an elongate wick, which transports liquid aerosol-generating substrate from the storage portion of the cartridge to the coil of wire. In use, an electric current may be passed through the coil of wire to heat the liquid aerosol-generating substrate to generate an aerosol.

[0006] It is known to provide liquid or gel aerosol-generating substrates in a reservoir. Known reservoirs may comprise hollow containers configured to retain the aerosol-generating substrate.

[0007] Aerosol-generating substrates containing, for example, liquid or gel formulations may be prone to leakage of the liquid or gel formulation during storage, handling and use thereof. Leakage of the liquid or gel formulation may be exacerbated by high environmental temperatures and humidities. Loss of liquid or gel formulation through leakage may disadvantageously reduce the lifespan of the aerosol-generating article comprising the aerosol-generating substrate. Leakage of liquid or gel formulation may negatively impact the overall performance of the aerosolgenerating article. For example, leakage of liquid or gel formulation may negatively impact the consistency of the inhalable aerosol generated by an aerosol-generating system comprising the aerosol-generating article. Leakage of liquid or gel formulation may disadvantageously damage or impair the function of other components of an aerosol-generating system. For example, leakage of liquid or gel formulation from an aerosol-generating substrate may disadvantageously damage or impair the function of an aerosol-generating device interacting with the aerosolgenerating substrate.

[0008] Volatile components, such as flavourants, may evaporate, migrate, or sublimate over time. Evaporation, migration, and sublimation of flavourants may be exacerbated by high environmental temperatures and humidities. Loss of flavourants during storage through evaporation, migration, or sublimation may negatively impact the overall performance of an aerosol-generating article containing such an aerosol-generating substrate. This may disadvantageously reduce the shelflife of the aerosol-generating article. For example, evaporation, migration, and sublimation over time of one or more flavourants may negatively impact the perceived taste of the inhalable aerosol generated by an aerosol-generating system comprising the aerosol-generating article.

[0009] In aerosol-generating systems comprising an aerosol-generating substrate containing a liquid or gel formulation, energy may be supplied to the heater for a period of time following actuation of the heater until a bulk liquid or gel formulation is heated to a sufficient temperature to generate aerosol. This may result in a large amount of energy being used in order to generate the aerosol. This may also result in a short delay following actuation of the heater before the liquid or gel formulation is heated to a sufficient temperature to generate aerosol. Consequently, there may be poor aerosol generation and delivery at the beginning of the user experience.

[0010] Liquid and gel formulations of aerosol-generating articles for use in aerosol-generating systems may comprise one or more components which thermally degrade when exposed to extreme temperatures, for example, during intense heating regimes. Such progressive thermal degradation may negatively impact the overall performance of aerosol-generating articles containing the liquid or gel formulation. For example, progressive thermal degradation over time of one or more components in a liquid or gel formulation may negatively impact the perceived taste of the inhalable aerosol generated by an aerosol-generating system comprising the aerosolgenerating article.

[0011] It would be desirable to provide an aerosol-generating article comprising an aerosolgenerating substrate in which leakage of aerosol-generating substrate during storage, handling and use of the aerosol-generating article is prevented or reduced compared to known aerosolgenerating articles.

[0012] It would be desirable to provide an aerosol-generating article comprising an aerosolgenerating substrate in which evaporation, migration, or sublimation over time of one or more components of the aerosol-generating substrate is prevented or reduced compared to known aerosol-generating articles. It would be desirable to provide an aerosol-generating article comprising an aerosolgenerating substrate in which thermal degradation of one or more components of the aerosolgenerating substrate is prevented or reduced compared to known aerosol-generating articles.

[0013] It would be desirable to provide an aerosol-generating article comprising an aerosolgenerating substrate that allows for more energy efficient aerosol generation compared to known aerosol-generating articles.

[0014] It would be desirable to provide an aerosol-generating article comprising an aerosolgenerating substrate that allows for more consistent aerosol generation and delivery to a user compared to known aerosol-generating articles.

[0015] It would be desirable to provide an aerosol-generating article comprising an aerosolgenerating substrate that allows for greater control over aerosol generation and delivery to a user compared to known aerosol-generating articles.

[0016] According to the present disclosure there is provided an aerosol-generating article. The aerosol-generating article may comprise a downstream section. The downstream section may comprise a downstream plug. The aerosol-generating article may comprise an upstream section. The upstream section may comprise an upstream plug. The upstream section may be spaced apart from the downstream section. The upstream section may be located upstream of the downstream section. The aerosol-generating article may comprise an aerosol-generating substrate compartment between the downstream section and the upstream section. The substrate compartment may comprise a plurality of aerosol-generating elements. The plurality of aerosol-generating elements may comprise a carrier medium. An aerosol-generating substrate may be sorbed in the carrier medium. The downstream section and the upstream section may be configured to retain the aerosol-generating elements between the downstream section and the upstream section. The upstream section may define an upstream end of the aerosol-generating article. The upstream section may not comprise an aerosol-generating substrate.

[0017] According to the present invention there is provided an aerosol-generating article. The aerosol-generating article comprises a downstream section. The downstream section comprises a downstream plug. The aerosol-generating article comprises an upstream section. The upstream section comprises an upstream plug. The upstream section is spaced apart from the downstream section. The upstream section is located upstream of the downstream section. The aerosolgenerating article comprises a substrate compartment between the downstream section and the upstream section. The substrate compartment comprises a plurality of aerosol-generating elements. The plurality of aerosol-generating elements comprise a carrier medium. An aerosolgenerating substrate is sorbed in the carrier medium. The downstream section and the upstream section are configured to retain the aerosol-generating elements between the downstream section and the upstream section. The upstream section defines an upstream end of the aerosolgenerating article. The upstream section does not comprise an aerosol-generating substrate. Providing a substrate compartment between the downstream section and the upstream section comprising a plurality of aerosol-generating elements comprising a carrier medium and an aerosol-generating substrate sorbed in the carrier medium may advantageously reduce or prevent loss, for example by leakage, of the aerosol-generating substrate during storage, handling and use of aerosol-generating articles according to the present invention. In addition, providing a downstream section and an upstream section configured to retain the aerosolgenerating elements between the downstream section and the upstream section may also advantageously reduce or prevent loss of the aerosol-generating substrate during storage, handling and use of aerosol-generating articles according to the present invention. This may increase the lifespan of aerosol-generating articles according to the invention compared to known aerosol-generating articles. Reducing or preventing loss of the aerosol-generating substrate during storage, handling and use may advantageously improve the consistency of the inhalable aerosol generated by aerosol-generating articles according to the present invention compared to known aerosol-generating articles. Reducing or preventing loss of the aerosol-generating substrate during storage, handling and use of aerosol-generating articles according to the present invention may advantageously reduce or prevent damage to other components of aerosolgenerating systems comprising the aerosol-generating substrate.

[0018] Providing a substrate compartment between the downstream section and the upstream section comprising a plurality of aerosol-generating elements comprising a carrier medium, an aerosol-generating substrate sorbed in the carrier medium, and the downstream section and the upstream section configured to retain the aerosol-generating elements between the downstream section and the upstream section may advantageously reduce or prevent evaporation, migration or sublimation over time of the aerosol-generating substrate. This may advantageously increase the shelf-life of aerosol-generating articles according to the present invention compared to known aerosol-generating articles. Preventing or reducing evaporation, migration or sublimation over time of the aerosol-generating substrate may advantageously improve the perceived quality and consistency of the inhalable aerosol generated by aerosol-generating articles according to the present invention compared to known aerosol-generating articles. For example, preventing or reducing evaporation, migration or sublimation of the aerosol-generating substrate may advantageously improve the perceived taste of the inhalable aerosol generated by aerosolgenerating articles according to the present invention compared to known aerosol-generating articles.

[0019] Providing a substrate compartment between the downstream section and the upstream section comprising a plurality of aerosol-generating elements comprising a carrier medium and an aerosol-generating substrate sorbed in the carrier medium may advantageously prevent or reduce thermal degradation of components of the aerosol-generating substrate when exposed to extreme temperatures, for example, during intense heating regimes. Preventing or reducing progressive thermal degradation of components of the aerosol-generating substrate, for example during use, may advantageously improve the perceived quality and consistency of the inhalable aerosol generated by aerosol-generating articles according to the present invention compared to known aerosol-generating articles. This may also advantageously increase the lifetime of aerosolgenerating articles according to the present invention compared to known aerosol-generating articles. For example, preventing or reducing progressive thermal degradation over time of the aerosol-generating substrate may advantageously improve the perceived taste of the inhalable aerosol generated by aerosol-generating articles according to the present invention compared to known aerosol-generating articles.

[0020] Providing a substrate compartment between the downstream section and the upstream section comprising a plurality of aerosol-generating elements comprising a carrier medium and an aerosol-generating substrate sorbed in the carrier medium may advantageously result in more energy efficient aerosol generation compared to known aerosol-generating articles. In particular, advantageously during use of the aerosol-generating article the aerosol-generating substrate may be heated to a sufficient temperature to generate aerosol with a reduced amount of energy required to be supplied to a heater compared to known aerosol-generating articles. As a result, advantageously, during use of the aerosol-generating article the aerosol-generating substrate may be heated to a sufficient temperature to generate aerosol earlier in the user experience, with less of a delay following actuation of the heater, than in known aerosol-generating articles.

[0021] Providing a substrate compartment between the downstream section and the upstream section comprising a plurality of aerosol-generating elements comprising a carrier medium and an aerosol-generating substrate sorbed in the carrier medium may advantageously improve control over aerosol generation and delivery to a user compared to known aerosol-generating articles. In particular, advantageously, the number of aerosol-generating elements provided, the surface area of the aerosol-generating elements, the composition of the aerosol-generating elements, the structure of the aerosol-generating elements and arrangement of the aerosolgenerating elements can be selected to control the rate of aerosol generation as it is heated during use of an aerosol-generating article. For example, the rate and extent to which aerosolgenerating substrate is desorbed from the carrier medium of the aerosol-generating elements as it is heated during use of an aerosol-generating system may be controllable.

[0022] Providing a substrate compartment between the downstream section and the upstream section comprising a plurality of aerosol-generating elements comprising a carrier medium and an aerosol-generating substrate sorbed in the carrier medium may advantageously increase the rate of aerosolisation through the provision of a plurality of aerosol-generating elements with a larger total surface area for aerosolisation of the aerosol-generating substrate to occur from, compared to known aerosol-generating articles. Unless otherwise stated, references to “aerosol-generating element” herein refer to the combination of the carrier medium and the aerosol-generating substrate sorbed in the carrier medium.

[0023] As used herein with reference to the present invention, the term “carrier medium” denotes a component configured to contain or retain an aerosol-generating substrate.

[0024] As used herein with reference to the present invention, the term “sorbed in” refers to the process by which the carrier medium retains an aerosol-generating substrate. The sorption may include one or more of adsorption and absorption. For example, the sorption may comprise drawing the aerosol-generating substrate into any pores of the carrier medium by capillary action. It will be appreciated that “sorbed in” may also refer to the aerosol-generating substrate being adsorbed on the carrier medium. As described in more detail below, the carrier medium may comprise a solid continuous matrix structure. Where this is the case, the aerosol-generating substrate may trapped within the solid continuous matrix structure.

[0025] As used herein with reference to the present invention, the term “aerosol-generating substrate” denotes a substrate capable of releasing volatile compounds upon heating, which can condense to form an aerosol.

[0026] As used herein with reference to the present invention, the term “aerosol” denotes a dispersion of solid particles, or liquid droplets, or a combination of solid particles and liquid droplets, in a gas. The aerosol may be visible or invisible. The aerosol may include vapours of substances that are ordinarily liquid or solid at room temperature as well as solid particles, or liquid droplets, or a combination of solid particles and liquid droplets.

[0027] As used herein with reference to the present invention, the term “aerosol-generating article” denotes an article comprising an aerosol-generating substrate that is capable of releasing volatile compounds that can form an aerosol. An aerosol-generating article may be disposable.

[0028] As used herein with reference to the present invention, the terms ’upstream’, ‘downstream’, proximal’ and ‘distal’ are used to describe the relative positions of elements, or portions of elements, of aerosol-generating articles, aerosol-generating devices and aerosolgenerating systems according to the disclosure. Aerosol-generating articles as described herein comprise a proximal end through which, in use, an aerosol exits the aerosol-generating article. The proximal end may also be referred to as the mouth end. In use, a user draws on the proximal end or mouth end of the aerosol-generating article in order to inhale an aerosol generated by the aerosol-generating article. The aerosol-generating article comprises a distal end opposite the proximal end or mouth end. The proximal end or mouth end of the aerosol-generating article may also be referred to as the downstream end. The distal end of the aerosol-generating article may also be referred to as the upstream end. Components, or portions of components, of the aerosolgenerating article may be described as being upstream or downstream of one another based on their relative positions between the proximal or downstream end and the distal or upstream end of the aerosol-generating article.

[0029] As used herein with reference to the present invention, the term ‘longitudinal’ is used to describe the direction between the downstream end or proximal end and the opposed upstream end or distal end of aerosol-generating articles, aerosol-generating devices and aerosolgenerating systems according to the invention.

[0030] As used herein with reference to the present invention, the term ‘length’ is used to describe the maximum dimension of elements, or portions of elements, of aerosol-generating articles, aerosol-generating devices and aerosol-generating systems according to the disclosure in the longitudinal direction or along a longitudinal axis.

[0031] As used herein with reference to the present invention, the term ‘transverse’ is used to describe the direction perpendicular to the longitudinal direction.

[0032] As used herein, the term ‘width’ is used to describe the maximum transverse dimension of elements, or portions of elements, of aerosol-generating articles, aerosol-generating devices and aerosol-generating systems according to the disclosure.

[0033] Unless otherwise stated, references to the “cross-section” of the aerosol-generating article or a component of the aerosol-generating article refer to the transverse cross-section, perpendicular to the longitudinal direction or axis.

[0034] The upstream section defines an upstream end of the aerosol-generating article and the upstream section does not comprise an aerosol-generating substrate. In other words, there is no aerosol-generating substrate upstream of the substrate compartment. In other words, the aerosolgenerating substrate in the substrate compartment is the most upstream aerosol-generating substrate in the aerosol-generating article.

[0035] The substrate compartment comprises a plurality of aerosol-generating elements, the plurality of aerosol-generating elements comprise a carrier medium and an aerosol-generating substrate is sorbed in the carrier medium.

[0036] The aerosol-generating article may not comprise any aerosol-generating substrate downstream of the substrate compartment. The aerosol-generating article may not comprise any aerosol-generating substrate downstream of the substrate compartment and the aerosolgenerating article may not comprise any aerosol-generating substrate upstream of the substrate compartment. In other words, the aerosol-generating article may not comprise any aerosolgenerating substrate outside of the substrate compartment.

[0037] The aerosol-generating substrate sorbed in the carrier medium of the aerosol-generating elements within the substrate compartment may be the only aerosol-generating substrate in the aerosol-generating article. In other words, the aerosol-generating article may not comprise any other aerosol-generating substrate other than the aerosol-generating substrate sorbed in the carrier medium of the aerosol-generating elements within the substrate compartment. Preferably, the downstream plug and the upstream plug are configured to retain the aerosol-generating elements between the downstream plug and the upstream plug.

[0038] In other embodiments, the aerosol-generating elements may be spaced apart from one or both of the downstream plug and the upstream plug.

[0039] For example, a mesh or a perforated foil may be provided in one or both of the downstream section and the upstream section. Preferably, the mesh or perforated foil do not comprise any openings which would allow any of the plurality of aerosol-generating elements to pass through any of the openings.

[0040] For example, a mesh or a perforated foil may be provided between the downstream plug and the aerosol-generating elements. The mesh or perforated foil and the upstream plug may be configured to retain the aerosol-generating elements between the downstream section and the upstream section.

[0041] For example, a mesh or a perforated foil may be provided between the upstream plug and the aerosol-generating elements. The downstream plug and the mesh or perforated foil may be configured to retain the aerosol-generating elements between the downstream section and the upstream section.

[0042] For example, the aerosol-generating elements may be provided between a first mesh or perforated foil and a second mesh or perforated foil. The first mesh or perforated foil and the second mesh or perforated foil may be configured to retain the aerosol-generating elements between the downstream section and the upstream section.

[0043] The downstream plug may be non-tubular. The downstream plug may not comprise any channels therethrough. In other words, the downstream plug may be described as plain, having a filled cross-section or being a solid plug. Preferably, the downstream plug does not comprise any channels therethrough which would allow any of the plurality of aerosol-generating elements to pass through any of the channels.

[0044] The downstream plug may have a substantially uniform cross section. The downstream plug may have a substantially circular cross-sectional shape or a substantially oval cross- sectional shape. For example, the downstream plug may be a cylindrical plug element.

[0045] The downstream plug may comprise a fibrous filtration material. The downstream plug may be formed of a porous material. The downstream plug may comprise a plurality of pores. The downstream plug may comprise a plurality of openings. The downstream plug may be formed of a biodegradable material. The downstream plug may comprise a cellulose material. The downstream plug may comprise cellulose acetate.

[0046] For example, the downstream plug may be formed from a bundle of cellulose acetate fibres having a denier per filament between 10 and 15. For example, the downstream plug may be formed from relatively low density cellulose acetate tow, such as cellulose acetate tow comprising fibres of 12 denier per filament. Preferably, the downstream plug has a low particulate filtration efficiency. Preferably, the downstream plug is unventilated such that air does not enter the aerosol-generating article along the downstream plug.

[0047] The downstream plug may have a length of less than or equal to 4 millimetres, less than or equal to 3.5 millimetres, or less than or equal to 3 millimetres.

[0048] The downstream plug may have a length of greater than or equal to 2 millimetres, greater than or equal to 2.5 millimetres, or greater than or equal to 3 millimetres.

[0049] The downstream plug may have a length of between 2 millimetres and 4 millimetres, between 2 millimetres and 3.5 millimetres, between 2 millimetres and 3 millimetres, between 2.5 millimetres and 4 millimetres, between 2.5 millimetres and 3.5 millimetres, between 2.5 millimetres and 3 millimetres, between 3 millimetres and 4 millimetres, or between 3 millimetres and 3.5 millimetres. For example, the downstream plug may have a length of about 3 millimetres.

[0050] The downstream plug may have a width of greater than or equal to 5 millimetres, or greater than or equal to 6 millimetres.

[0051] The downstream plug may have a width of less than or equal to 7 millimetres, or less than or equal to 6 millimetres.

[0052] For example, the downstream plug may have a width of between 5 millimetres and 7 millimetres. For example, the downstream plug may have a width of about 6 millimetres.

[0053] The downstream plug may have a volume of less than or equal to 100 cubic millimetres, less than or equal to 85 cubic millimetres, or less than or equal to 70 cubic millimetres.

[0054] The downstream plug may have a volume of greater than or equal to 60 cubic millimetres, greater than or equal to 70 millimetres, or greater than or equal to 80 millimetres.

[0055] For example, the downstream plug may have a volume of between 60 cubic millimetres and 100 cubic millimetres. For example, the downstream plug may have a volume of about 85 cubic millimetres.

[0056] The upstream plug may be non-tubular. The upstream plug may not comprise any channels therethrough. In other words, the upstream plug may be described as plain, having a filled cross-section or being a solid plug. Preferably, the upstream plug does not comprise any channels therethrough which would allow any of the plurality of aerosol-generating elements to pass through any of the channels.

[0057] The upstream plug may have a substantially uniform cross section. The upstream plug may have a substantially circular cross-sectional shape or a substantially oval cross-sectional shape. For example, the upstream plug may be a cylindrical plug element.

[0058] The upstream plug may comprise a fibrous filtration material. The upstream plug may be formed of a porous material. The upstream plug may comprise a plurality of pores. The upstream plug may comprise a plurality of openings. The upstream plug may be formed of a biodegradable material. The upstream plug may comprise a cellulose material. The upstream plug may comprise cellulose acetate. For example, the upstream plug may be formed from a bundle of cellulose acetate fibres having a denier per filament between 10 and 15. For example, the upstream plug may be formed from relatively low density cellulose acetate tow, such as cellulose acetate tow comprising fibres of 12 denier per filament. Preferably, the upstream plug has a low particulate filtration efficiency. Preferably, the upstream plug is unventilated such that air does not enter the aerosol-generating article along the upstream plug.

[0059] The upstream plug may have a length of less than or equal to 4 millimetres, less than or equal to 3.5 millimetres, or less than or equal to 3 millimetres.

[0060] The upstream plug may have a length of greater than or equal to 2 millimetres, greater than or equal to 2.5 millimetres, or greater than or equal to 3 millimetres.

[0061] The upstream plug may have a length of between 2 millimetres and 4 millimetres, between 2 millimetres and 3.5 millimetres, between 2 millimetres and 3 millimetres, between 2.5 millimetres and 4 millimetres, between 2.5 millimetres and 3.5 millimetres, between 2.5 millimetres and 3 millimetres, between 3 millimetres and 4 millimetres, or between 3 millimetres and 3.5 millimetres. For example, the upstream plug may have a length of about 3 millimetres.

[0062] The upstream plug may have a width of greater than or equal to 5 millimetres, or greater than or equal to 6 millimetres.

[0063] The upstream plug may have a width of less than or equal to 7 millimetres, or less than or equal to 6 millimetres.

[0064] For example, the upstream plug may have a width of between 5 millimetres and 7 millimetres. For example, the upstream plug may have a width of about 6 millimetres.

[0065] The upstream plug may have a volume of less than or equal to 100 cubic millimetres, less than or equal to 85 cubic millimetres, or less than or equal to 70 cubic millimetres.

[0066] The upstream plug may have a volume of greater than or equal to 60 cubic millimetres, greater than or equal to 70 millimetres, or greater than or equal to 80 millimetres.

[0067] For example, the upstream plug may have a volume of between 60 cubic millimetres and 100 cubic millimetres. For example, the upstream plug may have a volume of about 85 cubic millimetres.

[0068] The ratio of the volume of the upstream plug to the volume of the downstream plug may be between 0.8 and 1 .2, between 0.9 and 1 .1 or between 0.95 and 1 .05.

[0069] The downstream plug and the upstream plug may have one or both of substantially the same length and substantially the same width. The downstream plug and the upstream plug may be formed from the same material.

[0070] Preferably, the downstream plug is immediately downstream of the substrate compartment. In other words, the downstream plug may abut a downstream end of the substrate compartment. Preferably, the downstream plug defines a downstream end of the substrate compartment. Preferably, the downstream plug is in contact with the plurality of aerosolgenerating elements.

[0071] Preferably, the upstream plug is immediately upstream of the substrate compartment. In other words, the upstream plug may abut an upstream end of the substrate compartment. Preferably, the upstream plug defines an upstream end of the substrate compartment. Preferably, the upstream plug is in contact with the plurality of aerosol-generating elements.

[0072] The downstream section may define a downstream end of the aerosol-generating article. For example, the downstream plug may define a downstream end of the aerosol-generating article.

[0073] The upstream section may define an upstream end of the aerosol-generating article. For example, the upstream plug may define an upstream end of the aerosol-generating article.

[0074] The substrate compartment may have a length of greater than or equal to 3 millimetres, greater than or equal to 4 millimetres, or greater than or equal to 5 millimetres.

[0075] The substrate compartment may have a length of less than or equal to 6 millimetres, less than or equal to 5 millimetres, or less than or equal to 4 millimetres.

[0076] For example, the substrate compartment may have a length of between 4 millimetres and

[0077] 6 millimetres. For example, the substrate compartment may have a length of about 4 millimetres. For example, the substrate compartment may have a length of about 5 millimetres.

[0078] The substrate compartment may have a width of greater than or equal to 5 millimetres, or greater than or equal to 6 millimetres.

[0079] The substrate compartment may have a width of less than or equal to 7 millimetres, or less than or equal to 6 millimetres.

[0080] For example, the substrate compartment may have a width of between 5 millimetres and

[0081] 7 millimetres. For example, the substrate compartment may have a width of about 6 millimetres.

[0082] A volume of the substrate compartment may be greater than or equal to 60 cubic millimetres, greater than or equal to 100 cubic millimetres, or greater than or equal to 140 cubic millimetres.

[0083] A volume of the substrate compartment may be less than or equal to 230 cubic millimetres, less than or equal to 170 cubic millimetres, less than or equal to 150 cubic millimetres, less than or equal to 130 cubic millimetres, less than or equal to 110 cubic millimetres, or less than or equal to 90 cubic millimetres.

[0084] For example, a volume of the substrate compartment may be between 60 cubic millimetres and 230 cubic millimetres. For example, a volume of the substrate compartment may be about 113 cubic millimetres. For example, a volume of the substrate compartment may be about 141 cubic millimetres.

[0085] A ratio of the volume of the substrate compartment to the volume of the downstream plug may be between 1 .05 and 2.75, between 1.15 and 2.25, or between 1 .25 and 1 .75. A ratio of the volume of the substrate compartment to the volume of the upstream plug may be between 1 .05 and 2.75, between 1.15 and 2.25, or between 1 .25 and 1 .75.

[0086] The aerosol-generating article may comprise at least one susceptor element. The substrate compartment may comprise at least one susceptor element. The substrate compartment may comprise a single susceptor element. The substrate compartment may comprise a plurality of susceptor particles. The plurality of susceptor particles may comprise a susceptor material and no aerosol-generating substrate. The plurality of susceptor particles may be interspersed or mixed with the plurality of aerosol-generating elements within the substrate compartment.

[0087] As used herein, the term “susceptor” denotes a material that is capable of being heated when penetrated by a varying magnetic field.

[0088] The aerosol-generating article may comprise one or more hollow tubular elements.

[0089] The downstream section may comprise the one or more hollow tubular elements.

[0090] The one or more hollow tubular elements may be formed from at least one of: cardboard, paper, a polymeric material, a cellulosic material, cellulose acetate, low density polyethylene (LDPE), and polyhydroxyalkanoate (PHA). Where the hollow tubular element is formed from paper, the paper may be crimped paper, such as crimped heat resistant paper or crimped parchment paper. Preferably, the one or more hollow tubular elements comprise a hollow acetate tube.

[0091] The one or more hollow tubular elements may be provided downstream of the downstream plug. The one or more hollow tubular elements may comprise a hollow tubular element located downstream of the substrate compartment.

[0092] The one or more hollow tubular elements may be located downstream of the substrate compartment. The one or more hollow tubular elements may comprise a hollow tubular element located downstream of the downstream plug. The hollow tubular element may be immediately downstream of the downstream plug. In other words, the upstream end of the hollow tubular element may abut a downstream end of the downstream plug. A downstream end of the hollow tubular element may define a downstream end of the aerosol-generating article.

[0093] The one or more hollow tubular elements may comprise a hollow tubular element located within the substrate compartment. The substrate compartment may be defined by the downstream end of the upstream section, the upstream end of the downstream section and an inner surface of the hollow tubular element. The substrate compartment may be defined by the downstream end of the upstream plug, the upstream end of the downstream plug and an inner surface of the hollow tubular element.

[0094] As used herein, the term “hollow tubular element" is used to denote a generally elongate element defining a lumen or airflow passage along a longitudinal axis thereof. In particular, the term "tubular" will be used in the following with reference to a tubular element having a substantially cylindrical cross-section and defining at least one airflow conduit establishing an uninterrupted fluid communication between an upstream end of the tubular element and a downstream end of the tubular element. However, it will be understood that alternative geometries (for example, alternative cross-sectional shapes) of the tubular element may be possible.

[0095] The downstream section may comprise a mouth-end element. The mouth-end element may define a downstream end of the aerosol-generating article. The mouth-end element may be provided downstream of the downstream plug. The mouth-end element may be provided downstream of the one or more hollow tubular elements. The mouth-end element may be a mouth-end filter element. The mouth-end element may comprise a fibrous filtration material. The mouth-end element may comprise a cellulose material. The mouth-end element may comprise cellulose acetate. The mouth-end element may be a plug of cellulose acetate.

[0096] An aerosol-generating substrate is sorbed in the carrier medium of the plurality of aerosolgenerating elements.

[0097] Preferably, the aerosol-generating substrate comprises a liquid or a gel.

[0098] As used herein with reference to the present invention, the term “gel” is used to describe a substantially dilute cross-linked material, which exhibits no flow in the steady state.

[0099] Preferably, the aerosol-generating substrate comprises an aerosol-former.

[0100] The aerosol-generating substrate may comprise a polyhydric alcohol.

[0101] Preferably, in an aerosol-generating element according to the present invention, the polyhydric alcohol content in the aerosol-generating substrate accounts for at least 40 percent by weight based on the total weight of the aerosol-generating element.

[0102] Preferably, in an aerosol-generating element according to the present invention, the polyhydric alcohol content in the aerosol-generating substrate accounts for less than or equal to 75 percent by weight based on the total weight of the aerosol-generating element.

[0103] As defined above, an aerosol-generating element in accordance with the invention comprises a polyhydric alcohol as a component of the aerosol-generating substrate dispersed within the solid continuous matrix structure.

[0104] The polyhydric alcohol acts as the aerosol former of the aerosol-generating element. Polyhydric alcohols suitable for use in the aerosol-generating element include, but are not limited to, propylene glycol, triethylene glycol, 1 ,3-butanediol, and glycerin. Preferably, in an aerosolgenerating element in accordance with the invention the polyhydric alcohol is selected from the group consisting of glycerin, propylene glycol, and combinations thereof. In particularly preferred embodiments the polyhydric alcohol is glycerin.

[0105] The aerosol-generating substrate may comprise at least one alkaloid.

[0106] As used herein with reference to the present invention, the term “alkaloid compound” is used to describe any one of a class of naturally occurring organic compounds that contain one or more basic nitrogen atoms. Generally, an alkaloid contains at least one nitrogen atom in an amine-type structure. This or another nitrogen atom in the molecule of the alkaloid compound can be active as a base in acid-base reactions. Most alkaloid compounds have one or more of their nitrogen atoms as part of a cyclic system, such as for example a heterocylic 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 species and fungi. In the context of the present invention, the term “alkaloid compounds” is used to describe both naturally derived alkaloid compounds and synthetically manufactured alkaloid compounds. Suitable alkaloid compounds for use in an aerosol-generating element in accordance with the invention include, but are not limited to, nicotine and anatabine.

[0107] In preferred embodiments, the aerosol-generating substrate comprises nicotine or anatabine.

[0108] In particularly preferred embodiments, the aerosol-generating substrate comprises nicotine.

[0109] As used herein with reference to the present invention, the term “nicotine” is used to describe nicotine, a nicotine base or a nicotine salt. In embodiments in which the aerosolgenerating element comprises a nicotine base or a nicotine salt, the amounts of nicotine recited herein are the amount of free base nicotine or amount of protonated nicotine, respectively.

[0110] The aerosol-generating element may comprise natural nicotine or synthetic nicotine. The aerosol-generating element may comprise one or more monoprotic nicotine salts.

[0111] As used herein with reference to the invention, the term “monoprotic nicotine salt” is used to describe a nicotine salt of a monoprotic acid.

[0112] In general, the aerosol-generating element may comprise up to about 10 percent by weight of an alkaloid compound.

[0113] In some embodiments, the aerosol-generating substrate dispersed within the continuous solid matrix structure further comprises an acid. More preferably, the aerosol-generating substrate dispersed within the continuous solid matrix structure comprises one or more organic acids. Even more preferably, the aerosol-generating substrate dispersed within the continuous solid matrix structure comprises one or more carboxylic acids.

[0114] Suitable carboxylic acids for use in the aerosol-generating substrate of aerosol-generating elements in accordance with the present invention include, but are not limited to: 2-Ethylbutyric acid, acetic acid, adipic acid, benzoic acid, butyric acid, cinnamic acid, cycloheptane-carboxylic acid, fumaric acid, glycolic acid, hexanoic acid, lactic acid, levulinic acid, malic acid, myristic acid, octanoic acid, oxalic acid, propanoic acid, pyruvic acid, succinic acid, and undecanoic acid.

[0115] In particularly preferred embodiments, the acid is selected from the group consisting of lactic acid, levulinic acid, benzoic acid, citric acid and combinations thereof. Most preferably, the acid is lactic acid. The inclusion of an acid is especially preferred in embodiments of the aerosol-generating element wherein the aerosol-generating substrate dispersed within the continuous solid matrix structure comprises nicotine, as it has been observed that the presence of an acid may stabilise dissolved species in the aerosol-generating substrate, such as with nicotine and other plant extracts. Without wishing to be bound by theory, it is understood that the acid may interact with the nicotine molecule, such that protonated nicotine is stabilised. As protonated nicotine is nonvolatile, it is more easily found in the liquid or particulate phase rather than in the vapour phase of an aerosol obtained by heating the aerosol-generating element. As such, loss of nicotine during manufacturing of the aerosol-generating element can be minimised, and higher, better controlled nicotine delivery to the consumer can advantageously be ensured.

[0116] The aerosol-generating element may comprise up to about 10 percent by weight of an acid.

[0117] Preferably, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for at least 0.5 percent by weight of a total weight of the aerosolgenerating element. More preferably, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for at least 1 percent by weight of a total weight of the aerosol-generating element. Even more preferably, the acid content in the aerosolgenerating substrate dispersed within the solid porous substrate accounts for at least 2 percent by weight of a total weight of the aerosol-generating element.

[0118] Preferably, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for less than or equal to 8 percent by weight based on a total weight of the aerosol-generating element. More preferably, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for less than or equal to 5 percent by weight based on a total weight of the aerosol-generating element.

[0119] In some embodiments, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for from 0.5 percent by weight to 10 percent by weight, preferably from 1 percent by weight to 10 percent by weight, more preferably from 2 percent by weight to 10 percent by weight based on a total weight of the aerosol-generating element.

[0120] In other embodiments, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for from 0.5 percent by weight to 8 percent by weight, preferably from 1 percent by weight to 8 percent by weight, more preferably from 2 percent by weight to 8 percent by weight based on a total weight of the aerosol-generating element.

[0121] In further embodiments, the acid content in the aerosol-generating substrate dispersed within the solid porous substrate accounts for from 0.5 percent by weight to 5 percent by weight, preferably from 1 percent by weight to 5 percent by weight, more preferably from 2 percent by weight to 5 percent by weight based on a total weight of the aerosol-generating element. Where a multivalent acid, such as a multivalent carboxylic acid, is present in the aerosolgenerating substrate dispersed within the solid porous substrate in combination with nicotine, it may be preferable to provide a molar ratio of the acid groups to nicotine of between about 0.5:1 and about 2:1 , more preferably between about 0.75:1 and about 1 .5:1 , most preferably about 1 :1 . The use of a multivalent acid therefore enables a lower weight amount of the acid to be used whilst still providing the same level of protonation of the nicotine.

[0122] An aerosol-generating element according to the present invention preferably comprises less than or equal to about 25 percent by weight of water.

[0123] More preferably, the aerosol-generating element comprises less than or equal to about 20 percent by weight of water. Even more preferably, the aerosol-generating element comprises less than or equal to about 15 percent of water.

[0124] An aerosol-generating element in accordance with the present invention may optionally further comprise a flavourant. The flavourant may be in liquid form, or solid form. Optionally, the flavourant may be provided in a microencapsulated form wherein the flavourant is released upon heating.

[0125] Preferably, the aerosol-generating element comprises at least about 0.05 percent by weight of flavourant, more preferably at least about 0.1 percent by weight of flavourant based on the total weight of the aerosol-generating element. The aerosol-generating element preferably comprises less than or equal to about 1 percent by weight of flavourant, more preferably less than or equal to about 0.5 percent by weight of flavourant based on the total weight of the aerosolgenerating element.

[0126] In some embodiments, the aerosol-generating element comprises from about 0.05 percent by weight to about 1 percent by weight of flavourant, preferably from about 0.05 percent by weight to about 0.5 percent by weight of flavourant based on the total weight of the aerosolgenerating element. In other embodiments, the aerosol-generating element comprises from about 0.1 percent by weight to about 1 percent by weight of flavourant, preferably from about O.1 percent by weight to about 0.5 percent by weight of flavourant based on the total weight of the aerosolgenerating element.

[0127] Suitable flavourants for use in an aerosol-generating element in accordance with the present invention include, but are not limited to: menthol, mint such as peppermint or spearmint, cocoa, liquorice, fruit (such as citrus), gamma octalactone, vanillin, spices (such as cinnamon), methyl salicylate, linalool, eugenol, eucalyptol, bergamot oil, eugenol oil, geranium oil, lemon oil, ginger oil, and tobacco flavour.

[0128] The plurality of aerosol-generating elements may have any suitable shape. For example, the plurality of aerosol-generating elements may have a substantially ellipsoid shape, a substantially ovoid shape or a substantially spherical shape. Preferably, the plurality of aerosol-generating elements are substantially spherical. Advantageously, substantially spherical aerosol-generating elements have a maximum surface area for a given volume.

[0129] The substrate compartment may comprise greater than or equal to 2 aerosol-generating elements, greater than or equal to 3 aerosol-generating elements, greater than or equal to 5 aerosol-generating elements, greater than or equal to 10 aerosol-generating elements, greater than or equal to 20 aerosol-generating elements, greater than or equal to 30 aerosol-generating elements, or greater than or equal to 40 aerosol-generating elements.

[0130] The substrate compartment may comprise less than or equal to 200 aerosol-generating elements, less than or equal to 100 aerosol-generating elements, less than or equal to 75 aerosolgenerating elements, less than or equal to 50 aerosol-generating elements, or less than or equal to 40 aerosol-generating elements.

[0131] The substrate compartment may comprise between 2 and 200 aerosol-generating elements, between 2 and 100 aerosol-generating elements, between 2 and 75 aerosol-generating elements, between 2 and 50 aerosol-generating elements, between 2 and 40 aerosol-generating elements, between 3 and 200 aerosol-generating elements, between 3 and 100 aerosolgenerating elements, between 3 and 75 aerosol-generating elements, between 3 and 50 aerosolgenerating elements, between 3 and 40 aerosol-generating elements, between 5 and 200 aerosol-generating elements, between 5 and 100 aerosol-generating elements, between 5 and 75 aerosol-generating elements, between 5 and 50 aerosol-generating elements, between 5 and 40 aerosol-generating elements, between 10 and 200 aerosol-generating elements, between 10 and 100 aerosol-generating elements, between 10 and 75 aerosol-generating elements, between 10 and 50 aerosol-generating elements, between 10 and 40 aerosol-generating elements, between 20 and 200 aerosol-generating elements, between 20 and 100 aerosol-generating elements, between 20 and 75 aerosol-generating elements, between 20 and 50 aerosolgenerating elements, between 20 and 40 aerosol-generating elements, between 30 and 200 aerosol-generating elements, between 30 and 100 aerosol-generating elements, between 30 and 75 aerosol-generating elements, between 30 and 50 aerosol-generating elements, or between 30 and 40 aerosol-generating elements.

[0132] For example, the substrate compartment may comprise about 38 aerosol-generating elements.

[0133] A mean mass of the plurality of aerosol-generating elements may be greater than or equal to 0.6 milligrams, greater than or equal to 2 milligrams, greater than or equal to 10 milligrams, greater than or equal to 30 milligrams, greater than or equal to 50 milligrams, or greater than or equal to 70 milligrams. A mean mass of the plurality of aerosol-generating elements may be less than or equal to 80 milligrams, less than or equal to 60 milligrams, less than or equal to 40 milligrams, less than or equal to 20 milligrams, less than or equal to 10 milligrams, or less than or equal to 5 milligrams.

[0134] For example, a mean mass of the plurality of aerosol-generating elements may be between 0.6 milligrams and 80 milligrams.

[0135] As used herein with reference to the present invention, the term “mean mass of the plurality of aerosol-generating elements” is defined as the total mass of the plurality of aerosolgenerating elements divided by the total number of the plurality of aerosol-generating elements. Preferably, the total number of the plurality of the aerosol-generating elements is equal to the total number of aerosol-generating elements in the substrate compartment.

[0136] As used herein with reference to the present invention, the term “total mass of the plurality of aerosol-generating elements” is defined as the sum of the mass of each of the plurality of aerosol-generating elements.

[0137] A total mass of the plurality of aerosol-generating elements may be greater than or equal to 20 milligrams, greater than or equal to 60 milligrams, or greater than or equal to 100 milligrams.

[0138] A total mass of the plurality of aerosol-generating elements may be less than or equal to 120 milligrams, greater than or equal to 80 milligrams, or greater than or equal to 40 milligrams.

[0139] For example, a total mass of the plurality of aerosol-generating elements may be between 20 milligrams and 120 milligrams.

[0140] A mean surface area of the plurality of aerosol-generating elements may be greater than or equal to 3 millimetres squared, greater than or equal to 7 millimetres squared, greater than or equal to 10 millimetres squared, greater than or equal to 30 millimetres squared, greater than or equal to 50 millimetres squared, or greater than or equal to 70 millimetres squared.

[0141] A mean surface area of the plurality of aerosol-generating elements may be less than or equal to 80 millimetres squared, less than or equal to 60 millimetres squared, less than or equal to 40 millimetres squared, less than or equal to 20 millimetres squared, less than or equal to 10 millimetres squared, or less than or equal to 5 millimetres squared.

[0142] For example, a mean surface area of the plurality of aerosol-generating elements may be between 3 millimetres squared and 80 millimetres squared.

[0143] As used herein with reference to the present invention, the term “mean surface area of the plurality of aerosol-generating elements” is defined as the total surface area of the plurality of aerosol-generating elements divided by the total number of the plurality of aerosol-generating elements. Preferably, the total number of the plurality of aerosol-generating elements is equal to the total number of aerosol-generating elements in the substrate compartment.

[0144] As used herein with reference to the present invention, the term “total surface area of the plurality of aerosol-generating elements” is defined as the sum of the surface area of each of the plurality of aerosol-generating elements. A total surface area of the plurality of aerosol-generating elements may be greater than or equal to 120 millimetres squared, greater than or equal to 240 millimetres squared, or greater than or equal to 480 millimetres squared.

[0145] A total surface area of the plurality of aerosol-generating elements may be less than or equal to 650 millimetres squared, less than or equal to 500 millimetres squared, less than or equal to 350 millimetres squared, or less than or equal to 200 millimetres squared.

[0146] For example, a total surface area of the plurality of aerosol-generating elements may be between 120 millimetres squared and 650 millimetres squared.

[0147] A mean diameter of the plurality of aerosol-generating elements may be greater than or equal to 1 millimetre, greater than or equal to 2 millimetres, greater than or equal to 3 millimetres, or greater than or equal to 4 millimetres.

[0148] A mean diameter of the plurality of aerosol-generating elements may be less than or equal to 5 millimetres, less than or equal to 4 millimetres, less than or equal to 3 millimetres, or less than or equal to 2 millimetres.

[0149] A mean diameter of the plurality of aerosol-generating elements may be between 1 millimetre and 5 millimetres, between 1 millimetre and 4 millimetres, between 1 millimetre and 3 millimetres, between 1 millimetre and 2 millimetres, between 2 millimetres and 5 millimetres, between 2 millimetres and 4 millimetres, between 2 millimetres and 3 millimetres, between 3 millimetres and 5 millimetres, between 3 millimetres and 4 millimetres, or between 4 millimetres and 5 millimetres.

[0150] As used herein with reference to the present invention, the term “mean diameter of the plurality of aerosol-generating elements” is defined as the sum of the diameters of each of the plurality of aerosol-generating elements divided by the total number of the plurality of aerosolgenerating elements. Preferably, the total number of the plurality of aerosol-generating elements is equal to the total number of aerosol-generating elements in the substrate compartment.

[0151] For the avoidance of doubt, as used herein the term ‘diameter’ is used to describe the maximum dimension of elements, or portions of elements, of aerosol-generating articles, aerosolgenerating devices and aerosol-generating systems according to the disclosure. For elements having a substantially a circular cross-section or a substantially spherical shape, the term diameter refers to the diameter of the circular cross-section or the diameter of the sphere respectively. However, where the plurality of aerosol-generating elements have a shape which is not substantially spherical, the term ‘diameter’ may be used to refer to the maximum dimension of the plurality of aerosol-generating elements.

[0152] A median diameter of the plurality of aerosol-generating elements may be greater than or equal to 1 millimetre, greater than or equal to 2 millimetres, greater than or equal to 3 millimetres, or greater than or equal to 4 millimetres. A median diameter of the plurality of aerosol-generating elements may be less than or equal to 5 millimetres, less than or equal to 4 millimetres, less than or equal to 3 millimetres, or less than or equal to 2 millimetres.

[0153] A median diameter of the plurality of aerosol-generating elements may be between 1 millimetre and 5 millimetres, between 1 millimetre and 4 millimetres, between 1 millimetre and 3 millimetres, between 1 millimetre and 2 millimetres, between 2 millimetres and 5 millimetres, between 2 millimetres and 4 millimetres, between 2 millimetres and 3 millimetres, between 3 millimetres and 5 millimetres, between 3 millimetres and 4 millimetres, or between 4 millimetres and 5 millimetres.

[0154] As used herein with reference to the present invention, the term “median diameter of the plurality of aerosol-generating elements” refers to the “D50 size the plurality of aerosol-generating elements”. The D50 size is the diameter of an aerosol-generating element which splits the distribution of diameters of the plurality of aerosol-generating elements in half, where half of the plurality of aerosol-generating elements are larger than the D50 size and half of the plurality of aerosol-generating elements are smaller than the D50 size. The distribution of diameters of the plurality of aerosol-generating elements may be determined by laser diffraction. For example, the particle size distribution may be determined by laser diffraction using a Malvern Mastersizer 3000 laser diffraction particle size analyser in accordance with the manufacturer’s instructions.

[0155] A maximum diameter of the plurality of aerosol-generating elements may be less than or equal to 5 millimetres, less than or equal to 4 millimetres, less than or equal to 3 millimetres, or less than or equal to 2 millimetres.

[0156] As used herein with reference to the present invention, the term “maximum diameter of the plurality of aerosol-generating elements” refers to the largest diameter of the plurality of aerosol-generating elements. In other words, none of the plurality of aerosol-generating elements may have a diameter which is greater than the maximum diameter of the plurality of aerosolgenerating elements.

[0157] A minimum diameter of the plurality of aerosol-generating elements may be greater than or equal to 1 millimetre, greater than or equal to 2 millimetres, greater than or equal to 3 millimetres, greater than or equal to 4 millimetres, or greater than or equal to 5 millimetres.

[0158] As used herein with reference to the present invention, the term “minimum diameter of the plurality of aerosol-generating elements” refers to the smallest diameter of the plurality of aerosolgenerating elements. In other words, none of the plurality of aerosol-generating elements may have a diameter which is less than the minimum diameter of the plurality of aerosol-generating elements.

[0159] Where the downstream plug comprises at least one of a plurality of pores and a plurality of openings, a maximum width of the at least one of the plurality of pores and the plurality of openings may be less than a minimum diameter of the plurality of aerosol-generating elements. In other words, none of the plurality of aerosol-generating elements may have a diameter which is less than a width of any of the pores or opening in the downstream plug. Advantageously, this may prevent any of the plurality of aerosol-generating elements from entering any of the pores or opening in the downstream plug.

[0160] Where the upstream plug comprises at least one of a plurality of pores and a plurality of openings, a maximum width of the at least one of the plurality of pores and the plurality of openings may be less than a minimum diameter of the plurality of aerosol-generating elements. In other words, none of the plurality of aerosol-generating elements may have a diameter which is less than a width of any of the pores or opening in the upstream plug. Advantageously, this may prevent any of the plurality of aerosol-generating elements from entering any of the pores or opening in the upstream plug.

[0161] The mean volume of the plurality of aerosol-generating elements may be greater than or equal to 0.5 millimetres cubed, greater than or equal to 5 millimetres cubed, greater than or equal to 15 millimetres cubed, greater than or equal to 30 millimetres cubed, greater than or equal to 60 millimetres cubed.

[0162] The mean volume of the plurality of aerosol-generating elements may be less than or equal to 70 millimetres cubed, less than or equal to 40 millimetres cubed, less than or equal to 20 millimetres cubed, less than or equal to 10 millimetres cubed, or less than or equal to 4 millimetres cubed.

[0163] For example, a mean volume of the plurality of aerosol-generating elements may be between 0.5 millimetres cubed and 70 millimetres cubed.

[0164] As used herein with reference to the present invention, the term “mean volume of the plurality of aerosol-generating elements” is defined as the total volume of the plurality of aerosolgenerating elements divided by the total number of the plurality of aerosol-generating elements. Preferably, the total number of the plurality of aerosol-generating elements is equal to the total number of aerosol-generating elements in the substrate compartment.

[0165] As used herein with reference to the present invention, the term “total volume of the plurality of aerosol-generating elements” is defined as the sum of the volume of each of the plurality of aerosol-generating elements.

[0166] A total volume of the plurality of aerosol-generating elements may be greater than or equal to 20 millimetres cubed, greater than or equal to 50 millimetres cubed, or greater than or equal to 80 millimetres cubed.

[0167] A total volume of the plurality of aerosol-generating elements may be less than or equal to 105 millimetres cubed, less than or equal to 70 millimetres cubed, or less than or equal to 35 millimetres cubed.

[0168] For example, a total volume of the plurality of aerosol-generating elements may be between 20 millimetres cubed and 105 millimetres cubed. A total volume of the plurality of aerosol-generating elements may be greater than or equal to 40 percent of the total volume of the substrate compartment, greater than or equal to 50 percent of the total volume of the substrate compartment, greater than or equal to 60 percent of the total volume of the substrate compartment, greater than or equal to 70 percent of the total volume of the substrate compartment, or greater than or equal to 80 percent of the total volume of the substrate compartment.

[0169] A total volume of the plurality of aerosol-generating elements may be less than or equal to 90 percent of the total volume of the substrate compartment, less than or equal to 80 percent of the total volume of the substrate compartment, less than or equal to 70 percent of the total volume of the substrate compartment, less than or equal to 60 percent of the total volume of the substrate compartment, or less than or equal to 50 percent of the total volume of the substrate compartment.

[0170] For example, a total volume of the plurality of aerosol-generating elements may be between 40 percent and 70 percent of the total volume of the substrate compartment.

[0171] A mean density of the plurality of aerosol-generating elements may be greater than or equal to 1 milligram per cubic millimetre, or greater than or equal to 1.1 milligrams per cubic millimetre.

[0172] A mean density of the plurality of aerosol-generating elements may be less than or equal to 1 .2 milligrams per cubic millimetre.

[0173] For example, a mean density of the plurality of aerosol-generating elements may be between 1 milligram per cubic millimetre and 1 .2 milligrams per cubic millimetre.

[0174] As used herein, the term “mean density of the plurality of aerosol-generating elements” is defined as the total mass of the plurality of aerosol-generating elements divided by the total volume of the plurality of aerosol-generating elements.

[0175] For the avoidance of doubt, the terms “mass”, “volume”, “surface area”, “density” of the plurality of aerosol-generating elements may refer to the mass, volume, surface area and density respectively of the plurality of aerosol-generating elements with an aerosol-generating substrate sorbed in the carrier medium of the aerosol-generating elements, before use of the aerosolgenerating article.

[0176] The plurality of aerosol-generating elements comprise a carrier medium.

[0177] The carrier medium may comprise a solid continuous matrix structure and a solid porous substrate dispersed within the solid continuous matrix structure.

[0178] The solid continuous matrix structure may be an alginate matrix.

[0179] Alginate is a “matrix-forming polymer”, this term being used herein to denote an encapsulation material in the form of a polymer which is capable of producing a three-dimensional polymer matrix as a result of cross-linking when the matrix-forming polymer is brought into contact with a cross-linking solution of multivalent cations. The resultant polymer matrix is capable of trapping and retaining the aerosol-generating substrate within its cross-linked structure.

[0180] The aerosol-generating element may comprise an aerosol-generating substrate dispersed within the solid continuous matrix structure.

[0181] The aerosol-generating substrate may be trapped within the solid continuous matrix structure and releasable from the solid continuous matrix structure upon heating of the aerosolgenerating element.

[0182] The aerosol-generating element may further comprise a solid porous substrate also dispersed within the solid continuous matrix structure.

[0183] The solid porous substrate may comprise activated carbon.

[0184] The activated carbon content may account for at least 5 percent by weight based on the total weight of the aerosol-generating element.

[0185] A portion of the aerosol-generating substrate may be sorbed in the solid porous substrate. In an aerosol-generating element in accordance with the present invention the solid continuous matrix structure is an alginate matrix. Further, the aerosol-generating substrate dispersed within the solid continuous matrix structure comprises a polyhydric alcohol, and a polyhydric alcohol content in the aerosol-generating substrate trapped within the solid continuous matrix structure accounts for at least 40 percent by weight based on the total weight of the aerosol-generating element. In turn, the activated carbon content accounts for at least 5 percent by weight based on the total weight of the aerosol-generating element.

[0186] Preferably, in an aerosol-generating element according to the present invention the activated carbon content accounts for at least 10 percent by weight based on the total weight of the aerosol-generating element.

[0187] Preferably, in an aerosol-generating element according to the present invention the activated carbon content accounts for less than or equal to 25 percent by weight based on the total weight of the aerosol-generating element.

[0188] As used herein with reference to the present invention, the term “activated carbon” refers to a form of carbon which is highly porous over a broad range of pore sizes, from visible cracks and crevices to cracks and crevices of molecular dimensions resulting in very high internal surface area making it ideal for adsorption uses. Activated carbon is suitably defined by ASTM D2652-1 1 (Reapproved 2020) Standard Terminology Relating to Activated Carbon as “a family of carbonaceous substances manufactured by processes that develop adsorptive properties”. Activation is suitably defined by ASTM D2652-1 1 (Reapproved 2020) as “any process whereby a substance is treated to develop adsorptive properties”. Activated carbon may be formed by the pyrolysis of organic materials.

[0189] Preferably, the aerosol-generating element comprises at least 2 percent by weight of alginate based on the total weight of the aerosol-generating element. Preferably, the aerosol- generating element comprises less than or equal to 10 percent by weight of alginate based on the total weight of the aerosol-generating element.

[0190] The aerosol-generating substrate may be sorbed in the pores of the carrier medium.

[0191] The carrier medium may be substantially inert.

[0192] As used herein with reference to the present invention, the term “substantially inert” may refer to the carrier medium being inert under the operating temperatures of the aerosol-generating article and chemically inert with respect to chemicals in which the carrier medium is in contact in the aerosol-generating article.

[0193] The carrier medium may be chemically inert. In particular, the carrier medium may be chemically inert with respect to the aerosol-generating substrate sorbed in the carrier medium.

[0194] The carrier medium may inert under the operating temperatures of the aerosol-generating article. The carrier medium may be substantially resistant to thermal degradation at temperatures typically reached during use of an aerosol-generating system comprising the aerosol-generating article. This may prevent the generation of undesirable thermal decomposition products from the carrier medium.

[0195] The carrier medium may not contribute to aerosol generated during use of an aerosolgenerating system comprising the aerosol-generating article.

[0196] The carrier medium may have a loading capacity of aerosol-generating substrate of greater than or equal to 50 percent by weight.

[0197] The substrate compartment may further comprise tobacco or tobacco material. That is, the substrate compartment may comprise tobacco or tobacco material in addition to the plurality of aerosol-generating elements.

[0198] The tobacco or tobacco material may comprise homogenised tobacco material.

[0199] As used herein with reference to the present invention, the term ‘homogenised tobacco material’ denotes a material formed by agglomerating particulate tobacco.

[0200] The tobacco or tobacco material may be provided as shredded tobacco.

[0201] The tobacco or tobacco material may comprise a plurality of shreds of tobacco material, such as tobacco cut filler or shreds of homogenised tobacco material.

[0202] As used herein with reference to the present invention, the term “tobacco cut filler” is used to describe a plurality of strands of tobacco lamina.

[0203] As used herein with reference to the present invention, the term “shred” denotes an element having a length substantially greater than a width and a thickness thereof.

[0204] As used herein with reference to the present invention, the term “strand” describes an elongate element of material having a length that is substantially greater than the width and thickness thereof. The term “strand” should be considered to encompass strips, shreds and any other homogenised tobacco material having a similar form. Shreds of homogenised tobacco material may be formed from a sheet of homogenised tobacco material, for example, by cutting or shredding. Shreds of homogenised tobacco material may be formed by other methods, for example, by extrusion.

[0205] As used herein, the term ‘sheet’ denotes a laminar element having a width and length substantially greater than the thickness thereof.

[0206] The tobacco or tobacco material may comprise a gathered sheet of homogenised tobacco material. As used herein, the term ‘gathered’ is used to describe a sheet that is convoluted, folded, or otherwise compressed or constricted substantially transversely to the longitudinal axis of the aerosol-generating article.

[0207] The sheet of homogenised tobacco material may be crimped. As used herein with reference to the present invention, the term ‘crimped’ denotes a sheet having a plurality of substantially parallel ridges or corrugations. The tobacco or tobacco material may comprise a gathered, crimped sheet of homogenised tobacco material.

[0208] The plurality of aerosol-generating elements may be mixed with the tobacco or tobacco material. The plurality of aerosol-generating elements may be embedded in the tobacco or tobacco material. The plurality of aerosol-generating elements may be interspersed within the tobacco or tobacco material. For example, the plurality of aerosol-generating elements may be interspersed within shredded tobacco.

[0209] The aerosol-generating article may comprise a wrapper.

[0210] The wrapper may circumscribe at least part of the substrate compartment.

[0211] The wrapper may define at least part of the outer surface of the substrate compartment.

[0212] The substrate compartment may be defined by the downstream end of the upstream section, the upstream end of the downstream section and the wrapper. The substrate compartment may be defined by the downstream end of the upstream plug, the upstream end of the downstream plug and the wrapper.

[0213] The wrapper may extend along only a part of the length of the aerosol-generating article. The wrapper may extend along the entire length of the aerosol-generating article.

[0214] The wrapper may comprise one or more of cardboard, plastics, and metal foil. The wrapper may comprise a cellulosic material. The wrapper may comprise cellulosic material selected from one or more of paper, wood, textile, natural fibres, and artificial fibres. The wrapper may comprise cigarette paper. The wrapper may comprise tipping paper.

[0215] The plurality of aerosol-generating elements may comprise a first aerosol-generating element and a second aerosol-generating element. For example, the plurality of aerosolgenerating elements may comprise a plurality of first aerosol-generating elements and a plurality of second aerosol-generating elements. The second aerosol-generating element may have a different composition to the first aerosol-generating element. The carrier medium of the second aerosol-generating element may have a different composition to the carrier medium of the first aerosol-generating element.

[0216] The aerosol-generating substrate sorbed in the carrier medium of the second aerosolgenerating element may have a different composition to the aerosol-generating substrate sorbed in the carrier medium of the first aerosol-generating element. That is, the first aerosol-generating element may have a first aerosol-generating substrate sorbed in the carrier medium of the first aerosol-generating element and the second aerosol-generating element may have a second aerosol-generating substrate sorbed in the carrier medium of the second aerosol-generating element, the second aerosol-generating substrate having a different composition to the first aerosol-generating substrate.

[0217] The second aerosol-generating element may have a different diameter to the first aerosolgenerating element. The second aerosol-generating element may have a different volume to the first aerosol-generating element. The second aerosol-generating element may have a different mass to the first aerosol-generating element. The second aerosol-generating element may have a different surface area to the first aerosol-generating element.

[0218] For example, the second aerosol-generating element may have a different diameter and a different composition to the first aerosol-generating element.

[0219] As used herein with reference to the present invention, the term “different composition” refers to comprising one or more of a different chemical components, a different chemical structure, a different materials structure, or a different ratio of chemical components.

[0220] As used herein with reference to the present invention, the terms “different diameter”, “different volume”, “different mass”, and “different surface area” refer to having a difference in diameter, volume, mass and surface area respectively of at least 10%.

[0221] For example, where the plurality of aerosol-generating elements comprise a plurality of first aerosol-generating elements and a plurality of second aerosol-generating elements, the plurality of second aerosol-generating elements may have one or more of a different mean diameter, different mean volume, a different mean mass, and a different mean surface area to the plurality of first aerosol-generating elements.

[0222] As used herein with reference to the present invention, the terms “different mean diameter”, “different mean volume”, “different mean mass”, and “different mean surface area” refer to having a difference in mean diameter, mean volume, mean mass and mean surface area respectively of at least 10%.

[0223] The substrate compartment may be a single substrate compartment. In other words, the aerosol-generating article may comprise only one substrate compartment. The first aerosolgenerating element and the second aerosol-generating element may be located in the single substrate compartment. That is, the first aerosol-generating element and the second aerosol- generating element may be located in the same substrate compartment. The first aerosolgenerating element and the second aerosol-generating element may be in contact with each other. The first aerosol-generating element and the second aerosol-generating element may be mixed with each other. For example, a plurality of first aerosol-generating elements and a plurality of second aerosol-generating elements may be located in the single substrate compartment.

[0224] The substrate compartment may comprise a first substrate sub-compartment and a second substrate sub-compartment. That is, the substrate compartment may be split into two substrate sub-compartments. The first aerosol-generating element may be located in the first substrate sub-compartment and the second aerosol-generating element may be located in the second substrate sub-compartment. In other words, the first aerosol-generating element may be located in a different substrate compartment to the second aerosol-generating element. The first aerosol-generating element and the second aerosol-generating element may not be in contact with each other. For example, a plurality of first aerosol-generating elements may be located in the first substrate sub-compartment and a plurality of second aerosol-generating elements may be located in the second substrate sub-compartment.

[0225] The first substrate sub-compartment and the second substrate sub-compartment may have one or both of substantially the same length and substantially the same width. The first substrate sub-compartment and the second substrate sub-compartment may have substantially the same volume.

[0226] It will be appreciated that any of the features described herein for ‘the substrate compartment’ may apply to any of the single substrate compartment, the substrate compartment comprising a first substrate sub-compartment and a second substrate compartment, or each of the first substrate compartment and the second substrate compartment.

[0227] The second substrate sub-compartment may be arranged parallel to the first substrate sub-compartment. That is, the second substrate sub-compartment may be neither downstream or upstream of the first substrate sub-compartment.

[0228] Preferably, the second substrate sub-compartment is downstream of the first substrate sub-compartment. The second substrate sub-compartment may be separated from the first substrate sub-compartment by an intermediate plug. The intermediate plug may be configured to prevent contact between the first aerosol-generating element and the second aerosol-generating element. Preferably, the intermediate plug does not comprise any channels therethrough which would allow any of the first aerosol-generating element and the second aerosol-generating element to pass through any of the channels.

[0229] The intermediate plug may be non-tubular. The intermediate plug may not comprise any channels therethrough. In other words, the intermediate plug may be described as plain, having a filled cross-section or being a solid plug. Preferably, the intermediate plug does not comprise any channels therethrough which would allow any of the plurality of aerosol-generating elements to pass through any of the channels.

[0230] The intermediate plug may have a substantially uniform cross section. The intermediate plug may have a substantially circular cross-sectional shape or a substantially oval cross- sectional shape. For example, the intermediate plug may be a cylindrical plug element.

[0231] The intermediate plug may comprise a fibrous filtration material. The intermediate plug may be formed of a porous material. The intermediate plug may comprise a plurality of pores. The intermediate plug may comprise a plurality of openings. The intermediate plug may be formed of a biodegradable material. The intermediate plug may comprise a cellulose material. The intermediate plug may comprise cellulose acetate.

[0232] For example, the intermediate plug may be formed from a bundle of cellulose acetate fibres having a denier per filament between 10 and 15. For example, the intermediate plug may be formed from relatively low density cellulose acetate tow, such as cellulose acetate tow comprising fibres of 12 denier per filament. Preferably, the intermediate plug has a low particulate filtration efficiency. Preferably, the intermediate plug is unventilated such that air does not enter the aerosol-generating article along the intermediate plug.

[0233] The intermediate plug and the upstream plug may have substantially the same width. The intermediate plug and the upstream plug may be formed from the same material. A length of the intermediate plug may be less than or equal to the length of the upstream plug.

[0234] The intermediate plug and the downstream plug may have substantially the same width. The intermediate plug and the downstream plug may be formed from the same material. A length of the intermediate plug may be less than or equal to the length of the downstream plug.

[0235] The second substrate sub-compartment may be separated from the first substrate subcompartment by a mesh or a perforated foil. The mesh or perforated foil may be configured to prevent contact between the first aerosol-generating element and the second aerosol-generating element. Preferably, the mesh or perforated foil do not comprise any openings which would allow any of the first aerosol-generating element and the second aerosol-generating element to pass through any of the openings.

[0236] An aerosol-generating system may be provided. The aerosol-generating system may comprise any of the aerosol-generating articles disclosed above and an aerosol-generating device. The aerosol-generating device may be configured to heat the aerosol-generating article. The aerosol-generating device may comprise a heating element, or part of a heating element, for heating the aerosol-generating article.

[0237] As used herein with reference to the present invention, the term “aerosol-generating device” denotes a device that interacts with an aerosol-generating substrate to generate an aerosol. In some examples, the aerosol-generating device heats the aerosol-generating substrate to facilitate release of volatile compounds from the substrate. As used herein with reference to the present invention, the term “aerosol-generating system” refers to the combination of an aerosol-generating device and an aerosol-generating article.

[0238] Since the aerosol-generating system of this disclosure comprises an aerosol-generating article described herein, the advantages specified above for the aerosol-generating articles also apply to the system itself.

[0239] The aerosol-generating device may further comprise a device cavity configured to receive at least a part of the aerosol-generating article. The device cavity may have a closed end and an open end. The aerosol-generating article may be insertable into the device cavity via the open end. The device cavity may have substantially the same cross-sectional shape as the aerosolgenerating article.

[0240] The heating element may be in the form of a pin or a blade configured for insertion into the substrate compartment. The pin or blade may be located in the device cavity. When the substrate compartment of the aerosol-generating article is received in the device cavity, the pin or blade heating element may penetrate the substrate compartment, and heat the plurality of aerosol-generating elements from within the substrate compartment.

[0241] Alternatively or in addition, the heating element may an external heating element. That is, the heating element may be located around the periphery of the device cavity. The heating element may circumscribe the aerosol-generating article when the aerosol-generating article is at least party received in the device cavity. The external heating element may heat the plurality of aerosol-generating elements from outside the substrate compartment. The external heating element may be configured to exert a compressive force on the aerosol-generating article when the aerosol-generating article is at least party received in the device cavity.

[0242] Alternatively or in addition, as discussed above, the substrate compartment may comprise at least one susceptor element.

[0243] The aerosol-generating device may comprise one of a resistive heating element and a susceptor element.

[0244] The heating element may comprise a resistive heating element. The heating element may comprise an electrically resistive material. Suitable electrically resistive materials include but are not limited to: semiconductors such as doped ceramics, electrically “conductive” ceramics (such as, for example, molybdenum disilicide), carbon, graphite, metals, metal alloys and composite materials made of a ceramic material and a metallic material. Such composite materials may comprise doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbides. Examples of suitable metals include titanium, zirconium, tantalum and metals from the platinum group. Examples of suitable metal alloys include stainless steel, Constantan, nickel-, cobalt-, chromium-, aluminium-, titanium-, zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese- and iron-containing alloys, and super-alloys based on nickel, iron, cobalt, stainless steel, Timetai®, iron-aluminium based alloys and iron- manganese-aluminium based alloys. Timetai® is a registered trademark of Titanium Metals Corporation, 1999 Broadway Suite 4300, Denver Colorado. In composite materials, the electrically resistive material may optionally be embedded in, encapsulated or coated with an insulating material or vice-versa, depending on the kinetics of energy transfer and the external physicochemical properties required. The heating element may comprise a metallic etched foil insulated between two layers of an inert material. In that case, the inert material may comprise Kapton®, all-polyimide or mica foil. Kapton® is a registered trademark of E.l. du Pont de Nemours and Company, 1007 Market Street, Wilmington, Delaware 19898, United States of America.

[0245] The heating element may comprise a susceptor element.

[0246] As stated above, the term “susceptor” denotes a material that is capable of being heated when penetrated by a varying magnetic field. The aerosol-generating device may be capable of generating a fluctuating magnetic field of between 1 and 30 MHz, for example, between 2 and 10 MHz, for example between 5 and 7 MHz. The device may be capable of generating a fluctuating magnetic field having a field strength (H-field) of between 1 and 5 kA / m, for example between 2 and 3 kA / m, for example about 2.5 kA / m.

[0247] The susceptor element may be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from the aerosol-generating substrate. For example, the susceptor element may comprise a metal or carbon. The susceptor element may comprise or consist of a ferromagnetic material, for example a ferromagnetic alloy, ferritic iron, or a ferromagnetic steel or stainless steel. A suitable material may be, or comprise, aluminium. The susceptor element may be formed from 400 series stainless steels, for example grade 410, or grade 420, or grade 430 stainless steel.

[0248] Different materials will dissipate different amounts of energy when positioned within electromagnetic fields having similar values of frequency and field strength. Thus, parameters of the susceptor element, such as material type, length, width, and thickness may all be altered to provide a desired power dissipation within a known electromagnetic field.

[0249] Where a susceptor element is provided, the aerosol-generating device may comprise an inductor coil arranged to inductively heat the susceptor element. The aerosol-generating device may comprise an inductor coil. Where the aerosol-generating device comprises a device cavity, the inductor coil may at least partly circumscribe the device cavity. The inductor coil may be arranged to coaxially circumscribe the device cavity.

[0250] The aerosol-generating device may further comprise a controller.

[0251] The aerosol-generating device may further comprise a power supply. The power supply may be a DC power supply. The power supply may a battery. The power supply may be a nickel- metal hydride battery, a nickel cadmium battery, or a lithium based battery, for example a lithiumcobalt, a lithium-iron-phosphate or a lithium-polymer battery. The power supply may be another form of charge storage device, such as a capacitor. The power supply may require recharging and may have a capacity that allows for the storage of enough energy for one or more user operations, for example one or more aerosol-generating experiences.

[0252] Below, there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0253] Example Ex1 : An aerosol-generating article, the aerosol-generating article comprising: a downstream section, the downstream section comprising a downstream plug ; an upstream section, the upstream section comprising an upstream plug, wherein the upstream section is spaced apart from the downstream section and wherein the upstream section is located upstream of the downstream section; and a substrate compartment between the downstream section and the upstream section, the substrate compartment comprising a plurality of aerosol-generating elements, wherein the plurality of aerosol-generating elements comprise a carrier medium and an aerosol-generating substrate sorbed in the carrier medium, wherein the downstream section and the upstream section are configured to retain the aerosol-generating elements between the downstream section and the upstream section, wherein the upstream section defines an upstream end of the aerosol-generating article, and wherein the upstream section does not comprise an aerosol-generating substrate.

[0254] Example Ex2: An aerosol-generating article according to example Ex1 , wherein the downstream plug and the upstream plug are configured to retain the aerosol-generating elements between the downstream plug and the upstream plug.

[0255] Example Ex3: An aerosol-generating article according to example Ex1 or Ex2, wherein the downstream plug comprises a fibrous filtration material.

[0256] Example Ex4: An aerosol-generating article according to any one of examples Ex1 to Ex3, wherein the downstream plug comprises a cellulose material, optionally wherein the downstream plug comprises cellulose acetate.

[0257] Example Ex5: An aerosol-generating article according to any preceding example, wherein the downstream plug defines a downstream end of the substrate compartment.

[0258] Example Ex6: An aerosol-generating article according to any preceding example, wherein the downstream plug defines the downstream end of the aerosol-generating article.

[0259] Example Ex7: An aerosol-generating article according to any preceding example, wherein the downstream section further comprises one or more hollow tubular elements, the one or more hollow tubular elements provided downstream of the downstream plug.

[0260] Example Ex8: An aerosol-generating article according to any preceding example, wherein the downstream plug has a length of less than or equal to 4 millimetres. Example Ex9: An aerosol-generating article according to any preceding example, wherein the downstream plug has a length of greater than or equal to 2 millimetres.

[0261] Example Ex10: An aerosol-generating article according to any preceding example, wherein the upstream plug comprises a fibrous filtration material.

[0262] Example Ex11 : An aerosol-generating article according to any preceding example, wherein the upstream plug comprises a cellulose material, optionally wherein the upstream plug comprises cellulose acetate.

[0263] Example Ex12: An aerosol-generating article according to any preceding example, wherein the upstream plug defines an upstream end of the substrate compartment.

[0264] Example Ex13: An aerosol-generating article according to any preceding example, wherein the upstream plug defines the upstream end of the aerosol-generating article.

[0265] Example Ex14: An aerosol-generating article according to any preceding example, wherein the upstream plug has a length of less than or equal to 4 millimetres.

[0266] Example Ex15: An aerosol-generating article according to any preceding example, wherein the upstream plug has a length of greater than or equal to 2 millimetres.

[0267] Example Ex16: An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises an aerosol-former.

[0268] Example Ex17: An aerosol-generating article according to any preceding example, wherein the aerosol-former is selected comprises polyhydric alcohol.

[0269] Example Ex18: An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises a flavourant.

[0270] Example Ex19: An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises nicotine.

[0271] Example Ex20: An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises one or both of tobacco and a botanical component.

[0272] Example Ex21 : An aerosol-generating article according to any preceding example, wherein the aerosol-generating substrate comprises a liquid or a gel.

[0273] Example Ex22: An aerosol-generating article according to any preceding example, wherein the carrier medium is porous.

[0274] Example Ex23: An aerosol-generating article according to any preceding example, wherein the carrier medium is substantially inert.

[0275] Example Ex24: An aerosol-generating article according to any preceding example, wherein the carrier medium comprises activated carbon.

[0276] Example Ex25: An aerosol-generating article according any preceding example, wherein the substrate compartment further comprises tobacco, optionally wherein the tobacco is provided as shredded tobacco. Example Ex26: An aerosol-generating article according to any preceding example, further comprising a wrapper circumscribing at least a part of the substrate compartment, optionally wherein the wrapper defines at least part of the outer surface of the substrate compartment.

[0277] Example Ex27: An aerosol-generating article according to any preceding example, wherein the plurality of aerosol-generating elements each have a substantially spherical shape.

[0278] Example Ex28: An aerosol-generating article according to any preceding example, wherein the substrate compartment comprises greater than or equal to 10 aerosol-generating elements.

[0279] Example Ex29: An aerosol-generating article according to any preceding example, wherein the substrate compartment comprises less than or equal to 50 aerosol-generating elements.

[0280] Example Ex30: An aerosol-generating article according to any preceding example, wherein a mean mass of the plurality of aerosol-generating elements is greater than or equal to 0.6 milligrams.

[0281] Example Ex31 : An aerosol-generating article according to any preceding example, wherein a mean mass of the plurality of aerosol-generating elements is less than or equal to 80 milligrams.

[0282] Example Ex32: An aerosol-generating article according to any preceding example wherein a mean surface area of the plurality of aerosol-generating elements is greater than or equal to 3 millimetres squared.

[0283] Example Ex33: An aerosol-generating article according to any preceding example, wherein a mean surface area of the plurality of aerosol-generating elements is less than or equal to 80 millimetres squared.

[0284] Example Ex34: An aerosol-generating article according to any preceding example, wherein a mean diameter of the plurality of aerosol-generating elements is greater than or equal to 1 millimetre.

[0285] Example Ex35: An aerosol-generating article according to any preceding example, wherein a mean diameter of the plurality of aerosol-generating elements is less than or equal to 5 millimetres.

[0286] Example Ex36: An aerosol-generating article according to any preceding example, wherein a minimum diameter of the plurality of aerosol-generating elements is greater than or equal to 1 millimetre.

[0287] Example Ex37: An aerosol-generating article according to any preceding example, wherein one or both of the downstream plug and the upstream plug comprise at least one of a plurality of pores and a plurality of openings. Example Ex38: An aerosol-generating article according to example Ex37, wherein a maximum width of the at least one of the plurality of pores and the plurality of openings is less than a minimum diameter of the plurality of aerosol-generating elements.

[0288] Example Ex39: An aerosol-generating article according to any preceding example, wherein a maximum diameter of the plurality of aerosol-generating elements is less than or equal to 5 millimetres.

[0289] Example Ex40: An aerosol-generating article according to any preceding example, wherein the mean volume of the plurality of aerosol-generating elements is greater than or equal to 0.5 millimetres cubed.

[0290] Example Ex41 : An aerosol-generating article according to any preceding example, wherein the mean volume of the plurality of aerosol-generating elements is less than or equal to 70 millimetres cubed.

[0291] Example Ex42: An aerosol-generating article according to any preceding example, wherein the total volume of the plurality of aerosol-generating elements is greater than or equal to 40 percent of the total volume of the substrate compartment.

[0292] Example Ex43: An aerosol-generating article according to any preceding example, wherein the total volume of the plurality of aerosol-generating elements is less than or equal to 70 percent of the total volume of the substrate compartment.

[0293] Example Ex44: An aerosol-generating article according to any preceding example, wherein the substrate compartment has a length of greater than or equal to 3 millimetres.

[0294] Example Ex45: An aerosol-generating article according to any preceding example, wherein the substrate compartment has a length of less than or equal to 6 millimetres.

[0295] Example Ex46: An aerosol-generating article according to any preceding example, wherein the substrate compartment has a width of greater than or equal to 5 millimetres.

[0296] Example Ex47: An aerosol-generating article according to any preceding example, wherein the substrate compartment has a width of less than or equal to 7 millimetres.

[0297] Example Ex48: An aerosol-generating article according to any preceding example, wherein the volume of the substrate compartment is greater than or equal to 60 cubic millimetres.

[0298] Example Ex49: An aerosol-generating article according to any preceding example, wherein the volume of the substrate compartment is less than or equal to 230 cubic millimetres.

[0299] Example Ex50: An aerosol-generating article according to any preceding example, wherein the total mass of the plurality of aerosol-generating elements is greater than or equal to 20 milligrams.

[0300] Example Ex51 : An aerosol-generating article according to any preceding example, wherein the total mass of the plurality of aerosol-generating elements is less than or equal to 120 milligrams. Example Ex52: An aerosol-generating article according to any preceding example, wherein the total volume of the plurality of aerosol-generating elements is greater than or equal to 20 millimetres cubed.

[0301] Example Ex53: An aerosol-generating article according to any preceding example, wherein the total volume of the plurality of aerosol-generating elements is less than or equal to 105 millimetres cubed.

[0302] Example Ex54: An aerosol-generating article according to any preceding example, wherein the total surface area of the plurality of aerosol-generating elements is greater than or equal to 120 millimetres squared.

[0303] Example Ex55: An aerosol-generating article according to any preceding example, wherein the total surface area of the plurality of aerosol-generating elements is less than or equal to 650 millimetres squared.

[0304] Example Ex56: An aerosol-generating article according to any preceding example, wherein the mean density of the plurality of aerosol-generating elements is greater than or equal to 1 milligram per cubic millimetre.

[0305] Example Ex57: An aerosol-generating article according to any preceding example, wherein the mean density of the plurality of aerosol-generating elements is less than or equal to 1 .2 milligrams per cubic millimetre.

[0306] Example Ex58: An aerosol-generating article according to any preceding example, wherein the substrate compartment further comprises at least one susceptor element.

[0307] Example Ex59: An aerosol-generating article according to any preceding example, wherein the plurality of aerosol-generating elements comprise a first aerosol-generating element and a second aerosol-generating element, the second aerosol-generating element having one or both of a different composition and a different diameter to the first aerosol-generating element.

[0308] Example Ex60: An aerosol-generating article according to example Ex59, wherein the substrate compartment is a single substrate compartment, and wherein the first aerosolgenerating element and the second aerosol-generating element are located in the single substrate compartment.

[0309] Example Ex61 : An aerosol-generating article according to example Ex59, wherein the substrate compartment comprises a first substrate sub-compartment and a second substrate subcompartment, wherein the first aerosol-generating element is located in the first substrate subcompartment and the second aerosol-generating element is located in the second substrate subcompartment.

[0310] Example Ex62: An aerosol-generating article according to example Ex61 , wherein the second substrate sub-compartment is downstream of the first substrate sub-compartment.

[0311] Example Ex63: An aerosol-generating article according to example Ex61 or Ex62, wherein the second substrate sub-compartment is separated from the first substrate sub-compartment by an intermediate plug, wherein the intermediate plug is configured to prevent contact between the first aerosol-generating element and the second aerosol-generating element.

[0312] Example Ex64: An aerosol-generating article according to example Ex63, wherein the intermediate plug comprises a cellulose material, optionally wherein the intermediate plug comprises cellulose acetate.

[0313] Example Ex65: An aerosol-generating system comprising: an aerosol-generating article according to any preceding example; and an aerosol-generating device configured to heat the aerosol-generating article.

[0314] Example Ex66: An aerosol-generating system according to example Ex65, wherein the aerosol-generating device comprises at least one of a resistive heating element and an inductive heating element.

[0315] The invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

[0316] Figure 1 is a cross-sectional view of an aerosol-generating article according to a first embodiment of the disclosure.

[0317] Figure 2 is a cross-sectional view of an aerosol-generating article according to a second embodiment of the disclosure.

[0318] Figure 3 is a cross-sectional view of an aerosol-generating article according to a third embodiment of the disclosure.

[0319] Figure 4 is a cross-sectional view of an aerosol-generating article according to a fourth embodiment of the disclosure.

[0320] Figure 5 is a cross-sectional view of an aerosol-generating system comprising the aerosolgenerating article of Figure 1 and an aerosol-generating device.

[0321] Figure 1 shows a schematic cross-sectional view of an aerosol-generating article 100. The aerosol-generating article 100 has a substantially cylindrical shape along its length.

[0322] The aerosol-generating article 100 comprises a downstream section 101. The downstream section 101 comprises a downstream plug 102 and a hollow tubular element 103. The downstream plug 102 is a cellulose acetate plug. The hollow tubular element 103 is a hollow acetate tube. The hollow tubular element 103 is provided immediately downstream of the downstream plug 102. A downstream end of the hollow tubular element 103 defines a downstream end 104 of the aerosol-generating article 100.

[0323] The aerosol-generating article 100 comprises an upstream section 105. The upstream section 105 is located upstream of the downstream section 101. The upstream section 105 comprises an upstream plug 106. The upstream plug 106 is a cellulose acetate plug. The upstream section 105 defines an upstream end 107 of the aerosol-generating article 100. The upstream section 105 does not comprise an aerosol-generating substrate. The upstream section 105 is spaced apart from the downstream section 101. A substrate compartment 108 is between the downstream section 101 and the upstream section 105. The aerosol-generating article 100 comprises only one substrate compartment. The substrate compartment 108 comprises a plurality of aerosol-generating elements 109. The plurality of aerosol-generating elements 109 comprise a carrier medium and an aerosol-generating substrate sorbed in the carrier medium.

[0324] The downstream section 101 and the upstream section 105 are configured to retain the plurality of aerosol-generating elements 109 between the downstream section 101 and the upstream section 105. In particular, the downstream plug 102 and the upstream plug 106 are configured to retain the plurality of aerosol-generating elements 109 between the downstream plug 102 and the upstream plug 106.

[0325] The aerosol-generating article 100 comprises a wrapper 110. The wrapper 110 extends along the entire length of the aerosol-generating article 100. The substrate compartment 108 is defined by a downstream end of the upstream section 105, an upstream end of the downstream section 101 and the wrapper 110. In particular, the substrate compartment 108 is defined by a downstream end of the upstream plug 106, an upstream end of the downstream plug 102 and the wrapper 1 10.

[0326] Figure 2 shows a schematic cross-sectional view of an aerosol-generating article 200. The aerosol-generating article 200 has a substantially cylindrical shape along its length.

[0327] The aerosol-generating article 200 comprises a downstream section 201. The downstream section 201 comprises a downstream plug 202, a hollow tubular element 203 and a mouth-end filter element 204. The downstream plug 202 is a cellulose acetate plug. The hollow tubular element 203 is a hollow acetate tube. The hollow tubular element 203 is provided immediately downstream of the downstream plug 202. The mouth-end filter element 204 is provided immediately downstream of the hollow tubular element 203. The mouth-end filter element 204 comprises cellulose acetate. A downstream end of the mouth-end filter element 204 defines a downstream end 205 of the aerosol-generating article 200.

[0328] The aerosol-generating article 200 comprises an upstream section 206. The upstream section 206 is located upstream of the downstream section 201. The upstream section 206 comprises an upstream plug 207. The upstream plug 207 is a cellulose acetate plug. The upstream section 206 defines an upstream end 208 of the aerosol-generating article 200. The upstream section 206 does not comprise an aerosol-generating substrate.

[0329] The upstream section 206 is spaced apart from the downstream section 201 . A substrate compartment 209 is between the downstream section 201 and the upstream section 206. The aerosol-generating article 200 comprises only one substrate compartment. The substrate compartment 209 comprises a plurality of aerosol-generating elements 210, 21 1. The plurality of aerosol-generating elements 210, 211 comprise a plurality of first aerosolgenerating elements 210 and a plurality of second aerosol-generating elements 211 .

[0330] The plurality of first aerosol-generating elements 210 comprise a carrier medium and a first aerosol-generating substrate sorbed in the carrier medium. The plurality of second aerosolgenerating elements 21 1 comprise a carrier medium and a second aerosol-generating substrate sorbed in the carrier medium. The second aerosol-generating substrate has a different composition to the first aerosol-generating substrate.

[0331] The downstream section 201 and the upstream section 206 are configured to retain the plurality of aerosol-generating elements 210, 211 between the downstream section 201 and the upstream section 206. In particular, the downstream plug 202 and the upstream plug 207 are configured to retain the plurality of aerosol-generating elements 210, 211 between the downstream plug 202 and the upstream plug 207.

[0332] The aerosol-generating article 200 comprises a wrapper 212. The wrapper 212 extends along the entire length of the aerosol-generating article 200. The substrate compartment 209 is defined by a downstream end of the upstream section 206, an upstream end of the downstream section 201 and the wrapper 212. In particular, the substrate compartment 209 is defined by a downstream end of the upstream plug 207, an upstream end of the downstream plug 202 and the wrapper 212.

[0333] Figure 3 shows a schematic cross-sectional view of an aerosol-generating article 300. The aerosol-generating article 300 has a substantially cylindrical shape along its length.

[0334] The aerosol-generating article 300 comprises a downstream section 301. The downstream section 301 comprises a downstream plug 302. The downstream plug 302 is a cellulose acetate plug. A downstream end of the downstream plug 302 defines a downstream end 303 of the aerosol-generating article 300.

[0335] The aerosol-generating article 300 comprises an upstream section 304. The upstream section 304 is located upstream of the downstream section 301. The upstream section 304 comprises an upstream plug 305. The upstream plug 305 is a cellulose acetate plug. The upstream section 304 defines an upstream end 306 of the aerosol-generating article 300. The upstream section 304 does not comprise an aerosol-generating substrate.

[0336] The upstream section 304 is spaced apart from the downstream section 301 . A substrate compartment 307, 308 is between the downstream section 301 and the upstream section 304.

[0337] The substrate compartment 307, 308 comprises a plurality of aerosol-generating elements 309, 310. The plurality of aerosol-generating elements 309, 310 comprise a plurality of first aerosol-generating elements 309 and a plurality of second aerosol-generating elements 310.

[0338] The substrate compartment 307, 308 is split into two substrate sub-compartments. The substrate compartment 307, 308 comprises a first substrate sub-compartment 307 and a second substrate sub-compartment 308. The second substrate sub-compartment 308 is downstream of the first substrate sub-compartment 307.

[0339] The first substrate sub-compartment 307 comprises the plurality of first aerosol-generating elements 309. The plurality of first aerosol-generating elements 309 comprise a first carrier medium and a first aerosol-generating substrate sorbed in the first carrier medium.

[0340] The second substrate sub-compartment 308 comprises the plurality of second aerosolgenerating elements 310. The plurality of second aerosol-generating elements 310 comprise a second carrier medium and a second aerosol-generating substrate sorbed in the second carrier medium. The second aerosol-generating substrate has a different composition to the first aerosolgenerating substrate. The second carrier medium has a different composition to the first carrier medium. The plurality of second aerosol-generating elements 310 have a different mean diameter to the plurality of first aerosol-generating elements 309.

[0341] The second substrate sub-compartment 308 is separated from the first substrate subcompartment 307 by an intermediate plug 311 . The intermediate plug 31 1 is configured to prevent contact between the plurality of first aerosol-generating elements 309 and the plurality of the second aerosol-generating elements 310.

[0342] The downstream section 301 and the upstream section 304 are configured to retain the plurality of aerosol-generating elements 309, 310 between the downstream section 301 and the upstream section 304. In particular, the downstream plug 302 and the upstream plug 305 are configured to retain the plurality of aerosol-generating elements 309, 310 between the downstream plug 302 and the upstream plug 305.

[0343] The aerosol-generating article 300 comprises a wrapper 312. The wrapper 312 extends along the entire length of the aerosol-generating article 300.

[0344] The first substrate sub-compartment 307 is defined by a downstream end of the upstream section 304, an upstream end of the intermediate plug 311 and the wrapper 312. In particular, the first substrate sub-compartment 307 is defined by a downstream end of the upstream plug 305, an upstream end of the intermediate plug 311 and the wrapper 312.

[0345] The second substrate sub-compartment 308 is defined by a downstream end of the intermediate plug 31 1 , an upstream end of the downstream section 301 and the wrapper 312. In particular, the second substrate sub-compartment 308 is defined by a downstream end of the intermediate plug 311 , an upstream end of the downstream plug 302 and the wrapper 312.

[0346] Figure 4 shows a schematic cross-sectional view of an aerosol-generating article 400. The aerosol-generating article 400 has a substantially cylindrical shape along its length.

[0347] The aerosol-generating article 400 comprises a downstream section 401. The downstream section 401 comprises a downstream plug 402. The downstream plug 402 is a cellulose acetate plug. A downstream end of the downstream plug 402 defines a downstream end 403 of the aerosol-generating article 400. The aerosol-generating article 400 comprises an upstream section 404. The upstream section 404 is located upstream of the downstream section 401. The upstream section 404 comprises an upstream plug 405. The upstream plug 405 is a cellulose acetate plug. The upstream section 404 defines an upstream end 406 of the aerosol-generating article 400. The upstream section 404 does not comprise an aerosol-generating substrate.

[0348] The upstream section 404 is spaced apart from the downstream section 401 . A substrate compartment 407 is between the downstream section 401 and the upstream section 404. The aerosol-generating article 400 comprises only one substrate compartment. The substrate compartment 407 comprises a plurality of aerosol-generating elements 408. The plurality of aerosol-generating elements 408 comprise a carrier medium and an aerosol-generating substrate sorbed in the carrier medium.

[0349] The downstream section 401 and the upstream section 404 are configured to retain the plurality of aerosol-generating elements 408 between the downstream section 401 and the upstream section 404. In particular, the downstream plug 402 and the upstream plug 405 are configured to retain the plurality of aerosol-generating elements 408 between the downstream plug 402 and the upstream plug 405.

[0350] The substrate compartment further comprises shredded tobacco 409. The plurality of aerosol-generating elements 408 are interspersed within the shredded tobacco 409.

[0351] The aerosol-generating article 400 comprises a wrapper 410. The wrapper 410 extends along the entire length of the aerosol-generating article 400. The substrate compartment 407 is defined by a downstream end of the upstream section 404, an upstream end of the downstream section 401 and the wrapper 410. In particular, the substrate compartment 407 is defined by a downstream end of the upstream plug 405, an upstream end of the downstream plug 402 and the wrapper 410.

[0352] Figure 5 shows a schematic cross-sectional view of a portion of an aerosol-generating system 500 comprising the aerosol-generating article 100 of Figure 1 and an aerosol-generating device 501.

[0353] The aerosol-generating device 501 comprising a heating element in the form of an external heating element 502. The external heating element 502 is located around the periphery of a device cavity 503. The external heating element 502 is a resistive heating element.

[0354] In use, the user inserts the aerosol-generating article 100 into the device cavity 503 of the aerosol-generating device 501 , such that the external heating element 502 circumscribes the aerosol-generating article 100 when the aerosol-generating article 100 is received in the device cavity 503. The device cavity 503 has a substantially circular cross-sectional shape. The device cavity 503 has substantially the same cross-sectional shape as the aerosol-generating article 100.

[0355] The aerosol-generating device 501 further comprises a power supply (not shown) and electronics (not shown) that allow the external heater 502 to be actuated to heat the plurality of aerosol-generating elements 109 of the aerosol-generating article 100 when the aerosolgenerating article 100 is received in the device cavity 503. Such actuation may be manually operated or may occur automatically in response to a user drawing on the downstream end 104 of the aerosol-generating article 100 when the aerosol-generating article 100 is inserted into the device cavity 503. During use, the external heating element 502 is controlled to operate within a defined operating temperature range, below a maximum operating temperature.

[0356] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about". In this context, therefore, a number A is understood as A ± 10 percent of A. Within this context, a number A may be considered to include numerical values that are within general standard error for the measurement of the property that the number A modifies. The number A, in some instances as used in the appended claims, may deviate by the percentages enumerated above provided that the amount by which A deviates does not materially affect the basic and novel characteristic(s) of the claimed invention. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.

Claims

1. An aerosol generating article containing a downstream section, wherein the downstream section comprises a downstream plug; an upstream section, wherein the upstream section comprises an upstream plug, wherein the upstream section is located at a distance from said downstream section, and wherein the upstream section is located upstream relative to said downstream section; and a substrate compartment between a downstream section and an upstream section, wherein the substrate compartment comprises a plurality of aerosol-generating elements, wherein said plurality of aerosol-generating elements comprise a carrier medium and an aerosol-generating substrate sorbed in the carrier medium, in this case, the carrier medium is porous, wherein the downstream section and the upstream section are configured to hold aerosol generating elements between the downstream section and the upstream section, wherein the upstream section defines the upstream end of the aerosol generating article, the section located earlier in the flow does not contain an aerosol-generating substrate, in this case, the plug located earlier along the flow has a length greater than or equal to 2 mm, The plug located upstream contains fibrous filter material.

2. An aerosol generating article containing a downstream section, wherein the downstream section comprises a downstream plug, an upstream section, wherein the upstream section comprises an upstream plug, wherein the upstream section is located at a distance from said downstream section, and wherein the upstream section is located upstream relative to said downstream section; a substrate compartment between a downstream section and an upstream section, wherein the substrate compartment comprises a plurality of aerosol-generating elements, wherein said plurality of aerosol-generating elements comprise a carrier medium and an aerosol-generating substrate sorbed in the carrier medium, in this case, the carrier medium is porous, wherein the downstream section and the upstream section are configured to hold aerosol generating elements between the downstream section and the upstream section, wherein the upstream section defines the upstream end of the aerosol generating article, the section located earlier in the flow does not contain an aerosol-generating substrate, in this case, the plug located earlier along the flow has a length greater than or equal to 2 mm, The plug located upstream contains a cellulose material.

3. An aerosol generating article containing a downstream section, wherein the downstream section comprises a downstream plug, an upstream section, wherein the upstream section comprises an upstream plug, wherein the upstream section is located at a distance from said downstream section, and wherein the upstream section is located upstream relative to said downstream section, a substrate compartment between a downstream section and an upstream section, wherein the substrate compartment comprises a plurality of aerosol-generating elements, wherein said plurality of aerosol-generating elements comprise a carrier medium and an aerosol-generating substrate sorbed in the carrier medium, in this case, the carrier medium is porous, wherein the downstream section and the upstream section are configured to hold aerosol generating elements between the downstream section and the upstream section, wherein the upstream section defines the upstream end of the aerosol generating article, the section located earlier in the flow does not contain an aerosol-generating substrate, in this case, the plug located earlier along the flow has a length greater than or equal to 2 mm, The plug located upstream contains acetyl cellulose.

4. An aerosol generating article according to any one of claims 1 to 3, wherein the downstream plug and the upstream plug are configured to retain aerosol generating elements between the downstream plug and the upstream plug.

5. An aerosol generating article according to any of the preceding claims, wherein the downstream plug comprises a fibrous filter material.

6. An aerosol generating article according to any one of the preceding claims, wherein the downstream plug comprises a cellulosic material.

7. An aerosol generating article according to any one of the preceding claims, wherein the downstream stopper defines a downstream end of the substrate compartment.

8. An aerosol-generating article according to any one of the preceding claims, wherein the downstream stopper defines a downstream end of the aerosol-generating article.

9. An aerosol generating article according to any one of the preceding claims, wherein the downstream section further comprises one or more hollow tubular elements, wherein said one or more hollow tubular elements are formed downstream of said downstream plug.

10. An aerosol generating article according to any of the preceding claims, wherein the downstream stopper has a length less than or equal to 4 mm.

11. An aerosol generating article according to any of the preceding claims, wherein the upstream stopper defines an upstream end of the substrate compartment.

12. An aerosol-generating article according to any of the preceding claims, wherein the upstream stopper defines an upstream end of the aerosol-generating article.

13. An aerosol-generating article according to any one of the preceding claims, wherein said plurality of aerosol-generating elements comprise a first aerosol-generating element and a second aerosol-generating element, wherein the second aerosol-generating element has one or both of a different composition and a different diameter compared to the first aerosol-generating element.

14. The aerosol generating article of claim 13, wherein the substrate compartment is a single substrate compartment, and wherein the first aerosol generating element and the second aerosol generating element are located in the single substrate compartment.

15. The aerosol generating article of claim 13, wherein the substrate compartment comprises a first substrate sub-compartment and a second substrate sub-compartment, wherein the first aerosol generating element is located in the first substrate sub-compartment and the second aerosol generating element is located in the second substrate sub-compartment.

16. An aerosol generating article according to claim 15, wherein the second substrate sub-compartment is located downstream of the first substrate sub-compartment.