CN116847744A

CN116847744A - Aerosol-generating article comprising a tubular element

Info

Publication number: CN116847744A
Application number: CN202280012976.3A
Authority: CN
Inventors: R·N·R·A·巴蒂斯塔; 彭成
Original assignee: Philip Morris Products SA
Current assignee: Philip Morris Products SA
Priority date: 2021-02-10
Filing date: 2022-02-10
Publication date: 2023-10-03
Also published as: US20240090566A1; JP2024505989A; KR20230144047A; WO2022171769A1; EP4291050A1

Abstract

An aerosol-generating article has an upstream end and a downstream end, the aerosol-generating article defining a longitudinal direction between the upstream end and the downstream end. The aerosol-generating article comprises an aerosol-forming substrate. The aerosol-generating article comprises a tubular element arranged downstream of the aerosol-forming substrate and extending in a longitudinal direction, the tubular element comprising an air inlet. The aerosol-generating article comprises a flavour matrix comprising a flavour substance disposed downstream of the air inlet.

Description

Aerosol-generating article comprising a tubular element

Technical Field

The present invention relates to an aerosol-generating article comprising an aerosol-forming substrate for generating an inhalable aerosol upon heating.

Background

Aerosol-generating articles are known in the art in which an aerosol-forming substrate, such as a tobacco-containing substrate, is heated rather than combusted. The purpose of such heated aerosol-generating articles is to reduce the potentially harmful by-products generated by the combustion and pyrolytic degradation of tobacco in conventional cigarettes.

In heated aerosol-generating articles, the inhalable aerosol is typically generated by transferring heat from a heater to an aerosol-forming substrate. During heating, volatile compounds are released from the aerosol-forming substrate and entrained in the air. For example, volatile compounds may be entrained in air drawn through, over, around, or otherwise in the vicinity of the aerosol-generating article. As the released volatile compounds cool, the compounds condense to form an aerosol. The aerosol may be inhaled by the user. The aerosol may contain flavors, nicotine, and other desired ingredients.

The heating element may be comprised in an aerosol-generating device. The combination of the aerosol-generating article and the aerosol-generating device may form an aerosol-generating system.

In addition to the sol-forming matrix, the heated aerosol-generating article may also comprise a flavour matrix. By transferring heat from the heater to the flavor substrate, volatile compounds are released from the flavor substrate and become entrained in the air. As the released volatile compounds cool, they condense to form an aerosol, which may contain flavors, nicotine, and other desired ingredients. Aerosols formed from the flavor substrate may become entrained with aerosols formed from the aerosol-forming substrate. The resulting mixed aerosol may be inhaled by the user.

Disclosure of Invention

It is therefore desirable to provide an aerosol-generating article in which a mixed aerosol formed from an aerosol-forming substrate and from separate flavour substrates is generated in an efficient manner.

An aerosol-generating article may be provided. An aerosol-generating article has an upstream end and a downstream end, the aerosol-generating article defining a longitudinal direction between the upstream end and the downstream end. The aerosol-generating article may comprise an aerosol-forming substrate. The aerosol-generating article may comprise a tubular element arranged downstream of the aerosol-forming substrate and extending along the longitudinal direction. The tubular element may comprise an air inlet. The aerosol-generating article may comprise a flavour matrix disposed downstream of the air inlet. The flavor matrix can include a flavor configured to be fluid permeable when the temperature of the flavor is equal to or greater than the transmittance transition temperature of the flavor. The flavor may be configured to be substantially fluid impermeable when the temperature of the flavor is below the transmittance transition temperature of the flavor. The flavoring may be a gel composition.

An aerosol-generating article may be provided having an upstream end and a downstream end, the aerosol-generating article defining a longitudinal direction between the upstream end and the downstream end, the aerosol-generating article comprising:

an aerosol-forming substrate;

a tubular element disposed downstream of the aerosol-forming substrate and extending along the longitudinal direction, the tubular element comprising an air inlet;

a flavor substrate disposed downstream of the air inlet, the flavor substrate comprising a flavor configured to be fluid permeable when a temperature of the flavor is equal to or greater than a permeability transition temperature of the flavor and configured to be substantially fluid impermeable when the temperature of the flavor is less than the permeability transition temperature of the flavor.

As used herein, the term "tubular element" is used to refer to a generally elongated element that defines a lumen or airflow channel along its longitudinal axis. In particular, the term "tubular" will be used hereinafter to refer to a tubular element having a substantially cylindrical cross section and defining at least one gas flow channel establishing uninterrupted fluid communication between an upstream end of the tubular element and a downstream end of the tubular element. However, it should be understood that alternative geometries (e.g., alternative cross-sectional shapes) of the tubular element may be possible.

As used herein, the term "elongated" refers to an element having a length dimension that is greater than its width dimension or its diameter dimension, for example, twice or more than its width dimension or its diameter dimension.

The term "aerosol-generating article" is used herein to refer to articles in which an aerosol-forming substrate may be heated to produce an inhalable aerosol and deliver the inhalable aerosol to a consumer. As used herein, the term "aerosol-forming substrate" refers to a substrate capable of releasing volatile compounds that can form an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. The aerosol-forming substrate is typically part of an aerosol-generating article.

The aerosol-forming substrate may comprise nicotine. The nicotine-containing aerosol-forming substrate may be a nicotine salt substrate.

The aerosol-forming substrate may be a liquid. The aerosol-forming substrate may comprise a solid component and a liquid component. Preferably, the aerosol-forming substrate is a solid.

The aerosol-forming substrate may comprise a plant-based material. The aerosol-forming substrate may comprise tobacco. The aerosol-forming substrate may comprise a tobacco-containing material comprising volatile tobacco flavor compounds that are released from the aerosol-forming substrate upon heating. The aerosol-forming substrate may comprise a non-tobacco material. The aerosol-forming substrate may comprise a homogeneous plant-based material.

As used herein, the term "aerosol-generating device" refers to a device comprising a heater that interacts with an aerosol-forming substrate or flavor substrate of an aerosol-generating article to generate an aerosol.

As used herein with reference to the present invention, the term "strip" is used to denote a generally cylindrical element of substantially circular, oval or elliptical cross-section.

As used herein, the term "longitudinal" refers to a direction corresponding to the major longitudinal axis of the aerosol-generating article, which extends between the upstream and downstream ends of the aerosol-generating article. As used herein, the terms "upstream" and "downstream" describe the relative positions of an element or portion of an element of an aerosol-generating article with respect to the direction in which an aerosol is conveyed through the aerosol-generating article during use.

During use, air is drawn through the aerosol-generating article in the longitudinal direction. The term "transverse" refers to a direction perpendicular to the longitudinal axis. Unless otherwise indicated, any reference to an aerosol-generating article or a "cross-section" of a component of an aerosol-generating article refers to a cross-section.

The term "length" denotes the dimension of a component of the aerosol-generating article in the longitudinal direction. For example, it may be used to indicate the dimension of the strip or elongate tubular member in the longitudinal direction.

As used herein, the term "flavor matrix" relates to a matrix separate from an aerosol-forming matrix that is capable of releasing volatile compounds that can form an aerosol. Such volatile compounds may be released by heating the flavor matrix.

As described above, the aerosol-generating article according to the invention provides an improved element construction comprising a combination of a tubular element arranged downstream of the aerosol-forming substrate and comprising an air inlet, and a flavour substrate comprising a flavour substance and arranged downstream of the air inlet.

Generating a flavor aerosol upon heating using a flavor substrate comprising a flavor substance may be desired to generate a uniform and highly consistent flavor aerosol to entrain a substrate aerosol generated from an aerosol-forming substrate disposed upstream of the flavor substrate.

Providing the flavor substrate downstream of the air inlet included in the tubular element may be beneficial for controlling the amount of air flow provided with the flavor substrate. This may allow for customization of the flavor aerosol. This may also improve the consistency of the flavor aerosol generated by the flavor matrix upon heating.

The flavor material can be configured to be fluid-permeable when the temperature of the flavor material is equal to or greater than the transmittance transition temperature of the flavor material, and the flavor material can be configured to be substantially fluid-impermeable when the temperature of the flavor material is below the transmittance transition temperature of the flavor material.

Thus, the flavor matrix may be used to provide greater control over the overall Resistance To Draw (RTD) of the aerosol-generating article. In particular, the flavor matrix may be advantageously used to enable potential reduction of RTD due to changes in the permeability of the gel composition during use.

The tubular element preferably defines at least one airflow passage to establish uninterrupted fluid communication between an upstream location within the tubular element and a downstream location within the tubular element. The tubular member preferably defines at least one airflow passage to establish uninterrupted fluid communication between an upstream end of the tubular member and a downstream end of the tubular member. The flavor substrate is preferably configured to allow fluid flowing along the at least one gas flow channel to flow downstream of the flavor substrate when the temperature of the flavor is equal to or greater than the permeability transition temperature of the flavor. The flavor substrate is preferably configured to prevent fluid flowing along the at least one gas flow channel from flowing downstream of the flavor substrate when the temperature of the flavor is below the transmittance transition temperature of the flavor.

The flavor substrate may not extend across the entire cross section of the airflow channel to allow the airflow to flow toward the downstream end.

Alternatively, the flavor matrix may block the airflow channel. The flavor substrate may extend across the entire cross-section of one or more of the airflow channels so as to block airflow toward the downstream end. Thus, the flavor matrix may extend across about 100% of the cross section of the airflow channel. The flavor matrix can extend across at least about 25% of the cross-section of the airflow channel. The flavor matrix may extend across at least about 50% of the cross-section of the airflow channel. The flavor matrix can extend across at least about 75% of the cross section of the airflow channel.

Likewise, the flavor substrate may be used to alter the airflow within the aerosol-generating article by virtue of the change in the permeability of the flavor substance over the course of use. This may be particularly useful in aerosol-generating articles having at least two airflow channels, when the flavour matrix is provided in one of the airflow channels.

The flavoring may comprise a gel composition. The gel composition may be advantageous in that it may produce a particularly uniform and highly consistent flavor aerosol to entrain a matrix aerosol generated from an aerosol-forming matrix disposed upstream of the flavor matrix.

As used herein, the "transmittance transition temperature" of a material is the temperature at which the transmittance of the material changes drastically when the material is heated or cooled. It can be determined that the material is substantially fluid impermeable at temperatures below the permeability transition temperature and fluid permeable at temperatures at or above the permeability transition temperature.

The flavoring may be configured to be fluid permeable at 85 degrees celsius. The flavoring may be configured to be substantially fluid impermeable at 20 degrees celsius.

The permeability transition temperature of a material may be the phase transition temperature of the material. When heated to a phase transition temperature, the material may change from a solid to a liquid. When cooled to a phase transition temperature, the material may change from a liquid to a solid.

When the flavor material includes a gel composition, the transmittance transition temperature of the gel composition may be the phase transition temperature of the gel composition such that the gel composition may change from a solid gel to a liquid when the flavor matrix is heated to the phase transition temperature of the gel composition, and the gel composition may change from a liquid to a solid gel when the flavor matrix is cooled to the phase transition temperature of the gel composition.

The gel composition may be configured to be fluid permeable at 85 degrees celsius. The gel composition may be configured to be substantially fluid impermeable at 20 degrees celsius.

The flavoring may be thermally reversible. The gel composition may be thermoreversible.

As used herein, "thermoreversible" refers to a material, such as a flavor substance, whose characteristics (particularly permeability) can be reversed to a previous state by heating or cooling the material to a temperature corresponding to this previous state. In particular, if the material is at a first temperature below its permeability transition temperature such that the material has a first permeability at which the material is substantially fluid impermeable, then heated to at or above its permeability transition temperature such that the material reaches a second permeability at which the material is fluid permeable, and finally, the material is cooled to the first temperature, the permeability of the material is reversed to substantially the first permeability. Also, if the material is at or above a first temperature at which the material is at its permeability transition temperature such that the material has a first permeability at which the material is fluid permeable and then cools below its permeability transition temperature such that the material reaches a second permeability at which the material is substantially fluid impermeable and finally the material is heated to the first temperature and the material's permeability is reversed to substantially the first permeability.

Advantageously, by providing a thermoreversible material, in particular a thermoreversible flavour substance, such as a flavour substance comprising a thermoreversible gel, the aerosol-generating device may be configured to repeatedly alter characteristics of the aerosol-generating article during use, such as resistance to draw, the amount of air flow within the article or the amount of aerosol generated upon heating of the flavour matrix. In particular, the properties of the aerosol-generating article may be reversed to its previous state.

The transmittance transition temperature of a flavor substance, such as a gel composition, may be between 70 degrees celsius and 80 degrees celsius.

A transmittance transition temperature between 70 degrees celsius and 80 degrees celsius may be advantageous because this temperature can be easily achieved by heating the flavor substrate with an aerosol-generating device. This may facilitate changing the properties of the aerosol-generating article during use.

The flavoring substances such as gel compositions may preferably comprise alkaloid compounds selected from the group consisting of nicotine, anatabine, and combinations thereof.

The flavor substance, such as a gel composition, may include nicotine. The amount of nicotine may be between about 0.1% and about 4%, preferably between about 0.1% and about 2% nicotine.

The term "nicotine" refers to nicotine and nicotine derivatives, such as free base nicotine, nicotine salts and the like.

Flavoring substances such as gel compositions may include flavoring agents. The flavoring agent may include menthol, coffee derivative flavoring agents containing caffeine, guarana, taurine, glucuronolactone, or any combination thereof. Flavoring substances such as gel compositions may comprise about 0.2% to 4% flavoring agents, preferably about 0.4% to 2%. The flavoring agent may comprise menthol extract. The menthol extract may have a minimum of about 55% menthol (C ₁₀ H ₂₀ O). The flavoring agent may comprise vanilla extract. The vanilla extract may have at least about 20% vanilla extract (C ₈ H ₈ O ₃ )。

The flavor material such as a gel composition may include glycerol. The amount of glycerol may be between about 50% and about 75%, preferably between about 50% and about 65%.

Flavor substances such as gel compositions may include Hydroxic Poly Metyl Cellulose (HPMC). The amount of HPMC may be between about 15% and about 35%, preferably between about 18% and about 32%, more preferably between about 20% and about 30%, more preferably between about 21% and about 27%.

Flavoring substances such as gel compositions may include agar. The amount of agar may be between about 3% and about 10%, preferably between about 4% and about 7%.

The flavor substances such as gel compositions may include fibers. The amount of fiber may be between about 0.1% and about 12%, preferably between about 0.1% and 7%. The fibers may include cellulosic fibers. The fibers may have a length of at least about 8 microns. The fibers may have a length of less than about 15 microns. The fibers may have a length between about 8 microns and about 15 microns.

Flavoring substances such as gel compositions may include low methoxy (E440 i) pectin. The amount of low methoxy (E440 i) pectin may be between about 0.1% and about 9%, preferably between about 0.1% and 7%.

Flavoring substances such as gel compositions may include lactic acid. The amount of lactic acid may be between about 1.7% and about 3.1%, preferably between about 2.1% and about 2.9%.

The flavor substance such as a gel composition may include Ca lactate. The amount of Ca lactate may be between about 0.1% and about 7%, preferably between about 0.1% and about 3%.

The above amounts are given in weight percent. The amounts in the present disclosure are preferably given in weight percent.

The term "cannabinoid compound" refers to any of the naturally occurring compounds found in a portion of the Cannabis plant namely Cannabis (Cannabis sativa), cannabis indica (Cannabis sativa) and Cannabis sativa (Cannabis ruderalis). Cannabinoid compounds are particularly concentrated in female flower sequences. Naturally occurring cannabinoid compounds in cannabis plants include Cannabidiol (CBD) and Tetrahydrocannabinol (THC). In the present disclosure, the term "cannabinoid compound" is used to describe both naturally derived cannabinoid compounds and synthetically produced cannabinoid compounds.

Flavoring substances such as gel compositions may include cannabinoid compounds selected from the group consisting of Cannabidiol (CBD), tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), cannabidiol (CBDA), cannabinol (CBN), cannabigerol (CBG), cannabidene (CBC), cannabinol (CBL), secondary Cannabinol (CBV), tetrahydrosecondary cannabinol (THCV), secondary Cannabidiol (CBDV), secondary cannabinol (CBCV), secondary Cannabigerol (CBGV), cannabigerol monomethyl ether (CBGM), cannabigerol (CBE), cannabidopyranocyclone (CBT), and combinations thereof.

The flavoring may include hydroxypropyl methylcellulose. The flavoring may have a hydroxypropyl methylcellulose content of greater than about 0.5% by weight. Advantageously, the inventors have found that hydroxypropyl methylcellulose can be an effective binder for flavour substances.

The flavoring may have a hydroxypropyl methylcellulose content of greater than about 1% by weight. The flavoring may have a hydroxypropyl methylcellulose content of greater than about 5% by weight. The flavoring may have a hydroxypropyl methylcellulose content of greater than about 10% by weight. The flavoring may have a hydroxypropyl methylcellulose content of greater than about 15% by weight. The flavoring may have a hydroxypropyl methylcellulose content of greater than about 20% by weight.

The flavoring may have a hydroxypropyl methylcellulose content of less than about 50% by weight. The flavoring may have a hydroxypropyl methylcellulose content of less than about 45% by weight. The flavoring may have a hydroxypropyl methylcellulose content of less than about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of less than about 35% by weight. The flavoring may have a hydroxypropyl methylcellulose content of less than about 30% by weight. The flavoring may have a hydroxypropyl methylcellulose content of less than about 25% by weight. The flavoring may have a hydroxypropyl methylcellulose content of less than about 20% by weight.

The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 50% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 45% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 35% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 30% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 25% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 20% by weight.

The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 1% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 5% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 10% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 15% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 20% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 25% and about 40% by weight.

The flavoring may have a hydroxypropyl methylcellulose content of between about 0.5% and about 45% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 1% and about 45% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 1% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 5% and about 40% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 5% and about 35% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 10% and about 35% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 10% and about 30% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 15% and about 30% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 15% and about 25% by weight. The flavoring may have a hydroxypropyl methylcellulose content of between about 20% and about 25% by weight.

The flavor material can have a cellulose-based enhancer content of greater than about 0.5% by weight. The flavor material may have a cellulose-based enhancer content of greater than about 1% by weight. The flavor material can have a cellulose-based enhancer content of greater than about 5% by weight. The flavor material may have a cellulose-based enhancer content of greater than about 10% by weight. The flavor material can have a cellulose-based enhancer content of greater than about 15% by weight. The flavor material can have a cellulose-based enhancer content of greater than about 20% by weight.

The flavor material can have a cellulose-based enhancer content of less than about 50% by weight. The flavor material can have a cellulose-based enhancer content of less than about 45% by weight. The flavor material can have a cellulose-based enhancer content of less than about 40% by weight. The flavor material can have a cellulose-based enhancer content of less than about 35% by weight. The flavor material can have a cellulose-based enhancer content of less than about 30% by weight. The flavor material can have a cellulose-based enhancer content of less than about 25% by weight. The flavor material can have a cellulose-based enhancer content of less than about 20% by weight. The flavor material can have a cellulose-based enhancer content of less than about 15% by weight.

The flavor may have a cellulose-based enhancer content of between about 0.5% and about 50% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 45% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 35% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 30% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 25% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 20% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 15% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 10% by weight. The flavor may have a cellulose-based enhancer content of between about 0.5% and about 5% by weight.

The flavor may have a cellulose-based enhancer content of between about 1% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 5% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 10% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 15% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 20% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 25% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 30% and about 40% by weight. The flavor may have a cellulose-based enhancer content of between about 35% and about 40% by weight.

The flavor may have a cellulose-based enhancer content of between about 1% and about 35% by weight. The flavor may have a cellulose-based enhancer content of between about 5% and about 35% by weight. The flavor may have a cellulose-based enhancer content of between about 5% and about 30% by weight. The flavor may have a cellulose-based enhancer content of between about 10% and about 30% by weight. The flavor may have a cellulose-based enhancer content of between about 10% and about 25% by weight. The flavor may have a cellulose-based enhancer content of between about 15% and about 25% by weight. The flavor may have a cellulose-based enhancer content of between about 15% and about 20% by weight.

The one or more cellulose-based reinforcing agents may include cellulose fibers. Advantageously, the inventors have found that cellulose fibers can be cellulose-based reinforcement, which is particularly effective in increasing the tensile strength of the flavour mass.

The flavoring may have a cellulosic fiber content of greater than about 0.5 wt.%. The flavoring may have a cellulosic fiber content of greater than about 1 wt.%. The flavoring may have a cellulosic fiber content of greater than about 5% by weight. The flavoring may have a cellulosic fiber content of greater than about 10 wt.%. The flavoring may have a cellulosic fiber content of greater than about 15 wt.%. The flavoring may have a cellulosic fiber content of greater than about 20 wt.%.

The flavoring may have a cellulosic fiber content of less than about 50 wt.%. The flavoring may have a cellulosic fiber content of less than about 45 wt.%. The flavoring may have a cellulosic fiber content of less than about 40 wt.%. The flavoring may have a cellulosic fiber content of less than about 35 wt.%. The flavoring may have a cellulosic fiber content of less than about 30 wt.%. The flavoring may have a cellulosic fiber content of less than about 25 wt.%. The flavoring may have a cellulosic fiber content of less than about 20 wt.%. The flavoring may have a cellulosic fiber content of less than about 15 wt.%.

The flavoring may have a cellulosic fiber content of between about 0.5% and about 50% by weight. The flavoring may have a cellulosic fiber content of between about 0.5% and about 45% by weight. The flavoring may have a cellulosic fiber content of between about 0.5 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 0.5% and about 35% by weight. The flavoring may have a cellulosic fiber content of between about 0.5% and about 30% by weight. The flavoring may have a cellulosic fiber content of between about 0.5 wt.% and about 25 wt.%. The flavoring may have a cellulosic fiber content of between about 0.5% and about 20% by weight. The flavoring may have a cellulosic fiber content of between about 0.5 wt.% and about 15 wt.%. The flavoring may have a cellulosic fiber content of between about 0.5% and about 10% by weight. The flavoring may have a cellulosic fiber content of between about 0.5% and about 5% by weight.

The flavoring may have a cellulosic fiber content of between about 1 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 5 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 10 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 15 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 20 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 25 wt.% and about 40 wt.%. The flavoring may have a cellulosic fiber content of between about 30 wt.% and about 40 wt.%. The flavor substance may have a cellulosic fiber content of between about 35 wt% and about 40 wt%.

The flavoring may have a cellulosic fiber content of between about 1% and about 35% by weight. The flavor substance may have a cellulosic fiber content of between about 5% and about 35% by weight. The flavoring may have a cellulosic fiber content of between about 5% and about 30% by weight. The flavoring may have a cellulosic fiber content of between about 10 wt.% and about 30 wt.%. The flavoring may have a cellulosic fiber content of between about 10 wt.% and about 25 wt.%. The flavoring may have a cellulosic fiber content of between about 15 wt.% and about 25 wt.%. The flavoring may have a cellulosic fiber content of between about 15 wt.% and about 20 wt.%.

The one or more cellulose-based reinforcing agents may include microcrystalline cellulose. Advantageously, the inventors have found that microcrystalline cellulose can be a cellulose-based enhancer that is particularly effective in increasing the tensile strength of a flavor.

The flavor material may have a microcrystalline cellulose content of greater than about 0.5% by weight. The flavor material may have a microcrystalline cellulose content of greater than about 1% by weight. The flavor material may have a microcrystalline cellulose content of greater than about 5% by weight. The flavor material may have a microcrystalline cellulose content of greater than about 10% by weight. The flavor material may have a microcrystalline cellulose content of greater than about 15% by weight. The flavor material may have a microcrystalline cellulose content of greater than about 20% by weight.

The flavor material can have a microcrystalline cellulose content of less than about 50% by weight. The flavor material may have a microcrystalline cellulose content of less than about 45% by weight. The flavor material can have a microcrystalline cellulose content of less than about 40% by weight. The flavor material can have a microcrystalline cellulose content of less than about 35% by weight. The flavor material can have a microcrystalline cellulose content of less than about 30% by weight. The flavor material can have a microcrystalline cellulose content of less than about 25% by weight. The flavor material can have a microcrystalline cellulose content of less than about 20% by weight. The flavor material can have a microcrystalline cellulose content of less than about 15% by weight.

The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 50% by weight. The flavor substance may have a microcrystalline cellulose content between about 0.5% and about 45% by weight. The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content between about 0.5% and about 35% by weight. The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 30% by weight. The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 25% by weight. The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 20% by weight. The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 15% by weight. The flavor substance may have a microcrystalline cellulose content of between about 0.5% and about 10% by weight. The flavor substance may have a microcrystalline cellulose content between about 0.5% and about 5% by weight.

The flavor substance may have a microcrystalline cellulose content of between about 1% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 5% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 10% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 15% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 20% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 25% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 30% and about 40% by weight. The flavor substance may have a microcrystalline cellulose content of between about 35% and about 40% by weight.

The flavor substance may have a microcrystalline cellulose content of between about 1% and about 35% by weight. The flavor substance may have a microcrystalline cellulose content of between about 5% and about 35% by weight. The flavor substance may have a microcrystalline cellulose content of between about 5% and about 30% by weight. The flavor substance may have a microcrystalline cellulose content of between about 10% and about 30% by weight. The flavor substance may have a microcrystalline cellulose content of between about 10% and about 25% by weight. The flavor substance may have a microcrystalline cellulose content of between about 15% and about 25% by weight. The flavor substance may have a microcrystalline cellulose content of between about 15% and about 20% by weight.

The one or more cellulose-based reinforcing agents may include cellulose powder. Advantageously, the inventors have found that the cellulose powder can be a cellulose-based reinforcement, which is particularly effective in increasing the tensile strength of the flavour.

The flavoring may have a cellulose powder content of greater than about 0.5% by weight. The flavoring may have a cellulose powder content of greater than about 1% by weight. The flavoring may have a cellulose powder content of greater than about 5% by weight. The flavoring may have a cellulose powder content of greater than about 10% by weight. The flavor material may have a cellulose powder content of greater than about 15% by weight. The flavor material may have a cellulose powder content of greater than about 20% by weight.

The flavor material may have a cellulose powder content of less than about 50% by weight. The flavor material may have a cellulose powder content of less than about 45% by weight. The flavor material may have a cellulose powder content of less than about 40% by weight. The flavor material may have a cellulose powder content of less than about 35% by weight. The flavor material may have a cellulose powder content of less than about 30% by weight. The flavor material may have a cellulose powder content of less than about 25% by weight. The flavor material may have a cellulose powder content of less than about 20% by weight. The flavor material may have a cellulose powder content of less than about 15% by weight.

The flavor substance may have a cellulose powder content of between about 0.5% and about 50% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 45% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 35% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 30% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 25% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 20% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 15% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 10% by weight. The flavor substance may have a cellulose powder content of between about 0.5% and about 5% by weight.

The flavor substance may have a cellulose powder content of between about 1% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 5% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 10% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 15% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 20% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 25% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 30% and about 40% by weight. The flavor substance may have a cellulose powder content of between about 35% and about 40% by weight.

The flavor substance may have a cellulose powder content of between about 1% and about 35% by weight. The flavor substance may have a cellulose powder content of between about 5% and about 35% by weight. The flavor substance may have a cellulose powder content of between about 5% and about 30% by weight. The flavor substance may have a cellulose powder content of between about 10% and about 30% by weight. The flavor substance may have a cellulose powder content of between about 10% and about 25% by weight. The flavor substance may have a cellulose powder content of between about 15% and about 25% by weight. The flavor substance may have a cellulose powder content of between about 15% and about 20% by weight.

The flavoring may include carboxymethyl cellulose. Advantageously, the use of carboxymethyl cellulose may help reduce encrustation of the flavour material when used in the aerosol-generating article. In some examples, the use of carboxymethyl cellulose will eliminate encrustations. As used herein, "crusting" is interpreted as forming a solid layer on a component of an aerosol-generating article. The inventors have found that encrustation may occur because the components of the flavour may melt and then resolidify around the components of the aerosol-generating article. Crusting can be a particular problem when flavour substances are used with aerosol-generating devices comprising susceptors. If a crust forms on the susceptor, then the crust-forming susceptor becomes less effective at heating the flavor, which may result in reduced delivery of nicotine to the user and/or reduced aerosol formation from the flavor.

The carboxymethyl cellulose may include sodium carboxymethyl cellulose. Advantageously, the inventors have found that sodium carboxymethyl cellulose is carboxymethyl cellulose, which may be particularly effective in preventing the above-described crusting problems.

The flavor material may have a carboxymethyl cellulose content of greater than about 0.5 weight percent. The flavor material may have a carboxymethyl cellulose content of greater than about 1 weight percent. The flavor material may have a carboxymethyl cellulose content of greater than about 5 weight percent. The flavor material may have a carboxymethyl cellulose content of greater than about 10 weight percent.

The flavor material can have a carboxymethyl cellulose content of less than about 20 weight percent. The flavor material can have a carboxymethyl cellulose content of less than about 15 weight percent. The flavor material may have a carboxymethyl cellulose content of less than about 10 weight percent. The flavor material can have a carboxymethyl cellulose content of less than about 8 weight percent. The flavor material can have a carboxymethyl cellulose content of less than about 5 weight percent.

The flavor material may have a carboxymethyl cellulose content between about 0.5 wt.% and about 20 wt.%. The flavor material may have a carboxymethyl cellulose content between about 0.5 wt.% and about 15 wt.%. The flavor substance may have a carboxymethyl cellulose content between about 0.5 wt.% and about 10 wt.%. The flavor substance may have a carboxymethyl cellulose content between about 0.5 wt.% and about 8 wt.%. The flavor substance may have a carboxymethyl cellulose content between about 0.5 wt.% and about 5 wt.%.

The flavor material may have a carboxymethyl cellulose content between about 1 wt.% and about 20 wt.%. The flavor material may have a carboxymethyl cellulose content between about 5 wt.% and about 20 wt.%. The flavor material may have a carboxymethyl cellulose content between about 8 wt.% and about 20 wt.%. The flavor material may have a carboxymethyl cellulose content between about 10 wt.% and about 20 wt.%. The flavor material may have a carboxymethyl cellulose content between about 15 wt.% and about 20 wt.%.

The flavor material may have a carboxymethyl cellulose content between about 1 wt.% and about 15 wt.%. The flavor material may have a carboxymethyl cellulose content between about 1 wt.% and about 10 wt.%. The flavor material may have a carboxymethyl cellulose content between about 5 wt.% and about 10 wt.%. The flavor material may have a carboxymethyl cellulose content between about 5 wt.% and about 8 wt.%.

The flavor substances such as gel compositions may have a homogeneous distribution. Likewise, flavor substances such as gel compositions may be distributed in a variable manner within the flavor matrix.

The flavor matrix may include an outer layer. The outer layer may be useful for imparting a desired shape to the flavor substrate disposed within the aerosol-generating article.

The outer layer may be made of the same material as the rest of the flavor matrix, such as a flavor substance.

When the flavor substrate includes an outer layer, the flavor substrate can be manufactured by first depositing a core that includes the remainder of the flavor substrate, and then depositing a layer on the core to form the outer layer. This may allow for an efficient way of providing a flavour matrix to make an aerosol-generating article. The core and the outer layer may advantageously be manufactured by extrusion. The outer layer may not include a flavoring agent.

The flavour substances, such as gel compositions, may be configured to be in the solid state over a temperature range encompassing standard ambient temperatures for use with aerosol-generating articles. A suitable temperature range may be minus 20 degrees celsius to 70 degrees celsius.

When the flavor substance, such as a gel composition, is in a solid state, it may be configured to have sufficient resistance to deformation to provide mechanical stability to the flavor substrate for handling during manufacture, transportation, and use of the aerosol-generating article. The flavor substrate may have a deformation resistance of between about 0.5kgf and about 3kgf, preferably between about 1.3kgf and about 2.7kgf, more preferably between about 1.9kgf and about 2.5 kgf.

The anti-deformation strength of the flavor substances such as the gel composition can be adjusted as desired by adjusting the composition of the flavor substances. For example, adjusting the amount of Low Methoxy (LM) pectin in a flavor can affect the anti-deformation strength of the flavor. The amount of Low Methoxy (LM) pectin can be between about 0.5% and about 5%, preferably between about 1% and about 3%.

Advantageously, the gel composition may be solid at room temperature. By "solid" in this context is meant that the gel has a stable size and shape and does not flow. Room temperature in this context means about 25 degrees celsius. A gel may be defined as a substantially dilute crosslinked system that does not exhibit fluidity at steady state. Gels may be predominantly liquid by weight, but they behave like solids due to the three-dimensional cross-linked network within the liquid. It is the crosslinking within the fluid that gives the gel its structure (hardness). Thus, a gel may be a dispersion of liquid molecules within a solid, wherein liquid particles are dispersed in a solid medium.

The viscosity of the gel composition may be from about 1,000,000 to about 1 pascal per second, preferably from 100,000 to 10 pascals per second, preferably from 10,000 to 1,000 pascals per second, or from 1,000 to 100 pascals per second, or from 500 to 200 pascals per second, to provide the desired viscosity. Viscosity of the gel composition can be measured at 25℃for 1s by using an Anton Paar MCR 302 rheometer using parallel plate PP25 with a P-PTD200+H-PTD200 measurement cell ^-1 Is measured by obtaining the viscosity of the sample.

The mass of the gel composition may not change by more than about 20%, or may not change by more than about 15%, or may not change by more than about 10% when exposed to various environmental storage conditions. The composition may have an exterior shape having an exposed surface area that does not change by more than about 10%, or by not more than about 5%, or by not more than about 1% when exposed to various environmental conditions.

The gel composition may have a mass and the mass does not change by more than about 20%, or by not more than about 15%, or by not more than about 10% when exposed to a relative humidity in the range of about 10% to about 60%, at 24 degrees celsius, and at one atmosphere of pressure or typical storage conditions.

The gel composition may have an exterior shape having an exposed surface area that varies by no more than about 10%, or by no more than about 5%, or by no more than about 1% when exposed to a relative humidity in the range of about 10% to about 60%, a temperature of 24 degrees celsius, and an atmospheric pressure.

The gel composition may have an exposed surface area value (in m ² In kg) and a mass value (in kg) in a ratio of about 0.05:1 to about 1:1, or about 0.1:1 to about 1:1, or about 0.5:1 to about 1:0.1, a ratio of mass value to exposed surface area value,Or in the range of about 0.5:1 to about 1:0.5.

Advantageously, the gel composition may provide a predictable form of composition upon storage or shipment from the manufacturer to the consumer. The gel composition may substantially maintain its shape. The gel composition may not substantially release the liquid phase upon storage or shipment from the manufacturer to the consumer.

The gel composition of any permeability control element, such as a flavor matrix or a span element, may include at least glycerol. The gel composition, such as a flavor matrix or any permeability control element of the span element, may include at least HPMC. The gel composition of any permeability control element, such as a flavor matrix or a span element, may include at least agar. The gel composition, such as a flavor matrix or any permeability control element of the span element, may include at least lactic acid.

The gel composition of any permeability control element, such as a flavor matrix or a span element, may include at least glycerol and HPMC.

Gel compositions such as flavor matrices or any permeability control element spanning elements may include at least glycerol, HPMC, and agar.

Gel compositions such as flavor matrices or any permeability control element across elements may include at least glycerol, HPMC, agar, and lactic acid.

The gel composition may have a glycerol content of about 52% by weight. The gel composition may have a hydroxic poly metyl cellulose content of about 21.5 wt%. The gel composition may have a nicotine content of about 1.5% by weight. The gel composition may have an agar content of about 7.6 wt.%. The gel composition may have a fiber content of about 9% by weight. The fibers may be cellulosic fibers having a length of about 8 to about 15 microns. The gel composition may have a low methoxy pectin (E440 i) content of about 4 wt%. The gel composition may have a lactic acid content of about 2.3 wt.%. The gel composition may have a Ca content of lactic acid of about 2.1 wt%.

The gel composition may have a glycerol content of about 53% by weight. The gel composition may have a hydroxic poly metyl cellulose content of about 21 wt%. Gel composition May have a nicotine content of about 1.1% by weight. The gel composition may have an agar content of about 8% by weight. The gel composition may have a fiber content of about 6.8 wt.%. The fibers may be cellulosic fibers having a length of about 8 to about 15 microns. The gel composition may have a low methoxy pectin (E440 i) content of about 5 wt%. The gel composition may have a lactic acid content of about 2.1 wt.%. The gel composition may have a Ca content of lactic acid of about 1 wt%. The gel composition may have about 2% by weight menthol (C) with a minimum of 55% ₁₀ H ₂₀ O) menthol extract (FDA 21CFR182.20).

The gel composition may have a glycerol content of about 61% by weight. The gel composition may have a hydroxic poly metyl cellulose content of about 21 wt%. The gel composition may have a nicotine content of about 1.8% by weight. The gel composition may have an agar content of about 3% by weight. The gel composition may have a fiber content of about 7.2 wt.%. The fibers may be cellulosic fibers having a length of about 8 to about 15 microns. The gel composition may have a low methoxy pectin (E440 i) content of about 3 wt%. The gel composition may have a lactic acid content of about 3 wt.%.

The gel composition may have a glycerol content of about 60% by weight. The gel composition may have a hydroxic poly metyl cellulose content of about 22% by weight. The gel composition may have a nicotine content of about 1.8% by weight. The gel composition may have an agar content of about 2.4 wt.%. The gel composition may have a fiber content of about 5.3 wt.%. The fibers may be cellulosic fibers having a length of about 8 to about 15 microns. The gel composition may have a low methoxy pectin (E440 i) content of about 4 wt%. The gel composition may have a lactic acid content of about 2.8 wt.%. The gel composition may have about 1% by weight of the Ca lactate composition. The gel composition may have about 1.7% by weight of vanillin (C) with a minimum of 20% ₈ H ₈ O ₃ ) Content of vanilla extract (FDA 21CFR169.175).

The suction resistance of the aerosol-generating article at a temperature of the flavour object equal to or greater than the permeability transition temperature of the flavour object is comparable to that of the aerosol-generating article at a flavour objectThe mass has a suction resistance at a temperature at least about 10mm H greater than the permeance transition temperature of the flavor material ₂ O。

As discussed above, the permeability of the flavor substances (such as gel compositions) contained in the flavor matrix can be altered by cooling or heating the flavor matrix at a suitable temperature. In particular, the flavor substances contained in the flavor matrix may become fluid permeable when heated to its transmittance transition temperature. This may allow for a variation in the suction resistance to the inhaled aerosol-generating article that can be easily achieved and determined. The aerosol-generating article has a pull-out resistance at a temperature of the flavor equal to or greater than the permeability transition temperature of the flavor, of at least about 10mm H relative to the pull-out resistance of the aerosol-generating article at a temperature of the flavor below the permeability transition temperature of the flavor ₂ The difference in O is advantageous because it can provide a significant change in the user experience.

More preferably, the aerosol-generating article may have a suction resistance at a temperature of the flavor equal to or greater than the permeability transition temperature of the flavor that is at least about 20mm H greater than the suction resistance of the aerosol-generating article at a temperature of the flavor below the permeability transition temperature of the flavor ₂ O. Even more preferably, the suction resistance of the aerosol-generating article at a temperature of the flavour object that may be equal to or greater than the permeability transition temperature of the flavour object may be at least about 30mm H greater than the suction resistance of the aerosol-generating article at a temperature of the flavour object that is below the permeability transition temperature of the flavour object ₂ O。

The aerosol-generating article may have a suction resistance of greater than about 20mm H at a temperature of the flavor below the transmittance transition temperature of the flavor ₂ O, even more preferably greater than about 30mm H ₂ O, even more preferably greater than about 40mm H ₂ O, even more preferably greater than about 50mm H ₂ O, most preferably greater than about 60mm H ₂ O。

The aerosol-generating article may have a suction resistance of less than about 50mm H at a temperature of the flavor material equal to or greater than the transmittance transition temperature of the flavor material ₂ O, even more preferably less than about 40mm H ₂ O, evenMore preferably less than about 30mm H ₂ O, even more preferably less than about 20mm H ₂ O, most preferably less than about 10mm H ₂ O。

The distance between the upstream end of the aerosol-forming substrate and the downstream end of the flavor substrate may be less than about 40 millimeters, preferably less than about 30 millimeters, and even more preferably less than about 20 millimeters.

A distance between the upstream end of the aerosol-forming substrate and the downstream end of the flavor substrate within this range may be beneficial in that the substrate aerosol generated upon heating of the aerosol-forming substrate mixes with the flavor aerosol generated upon heating of the flavor substrate to form a more consistent aerosol that may be inhaled by the user.

The tubular element may have a length of between about 3.9mm and about 8mm, preferably between about 4.4mm and 7.8 mm.

The ratio between the length of the tubular element and the length of the aerosol-generating article may be between about 0.2 and about 0.45, more preferably between about 0.25 and 0.35.

Tubular elements having such a length or such a relative length compared to the length of the aerosol-generating article may also improve the mixing of the matrix aerosol generated upon heating of the aerosol-forming matrix, the flavor aerosol generated upon heating of the flavor matrix, and the outside air drawn into the tubular element through the air inlet.

The aerosol-generating article may comprise an adjustment member disposed on the tubular element and movable relative to the tubular element, such that the adjustment member is configured to change the size of the air inlet.

Providing an adjustment member to vary the size of the air inlet may be advantageous for controlling the amount of air flow within the aerosol-generating article during use. The adjustment member may be used in place of or in combination with a flavour substance to adjust the amount of airflow within the aerosol-generating article during use. This may allow for more versatility in the regulation of the airflow within the aerosol-generating article.

The adjustment member and the tubular element may be linearly movable relative to each other. The adjustment member and the tubular element may be configured to rotate relative to each other. The adjustment member and the tubular element may be configured to rotate and to move linearly relative to each other, e.g. by means of threads.

The tubular element may comprise an inner tube and an outer tube, the outer tube being arranged around the inner tube, wherein an outer gas flow channel is longitudinally delimited by the inner tube and the outer tube, wherein an inner gas flow channel is longitudinally delimited by the inner tube, and wherein at least the inner gas flow channel is adapted for a flow of a matrix aerosol towards the downstream end.

Providing the inner and outer airflow channels within the tubular member may enable at least two independent airflow paths within the tubular member. The inner airflow channel is generally adapted to flow a substrate aerosol generated upon heating of the aerosol-forming substrate toward the downstream end. The outer airflow channel generally includes an air inlet such that the outer airflow may be separated from the airflow path within the inner airflow channel. The outer airflow channel may also be adapted for flow of the matrix aerosol towards said downstream end.

The flavor substrate may be disposed within the outer airflow channel. This may be advantageous because a flavor substance, such as a gel composition, may be configured to regulate the airflow within the outer airflow channel. This may also enhance control of the airflow provided with the flavor substrate.

The aerosol-generating article may comprise at least one permeability control element, wherein the at least one permeability control element is configured to become fluid permeable when the temperature of the at least one permeability control element is equal to or greater than a permeability transition temperature of the at least one permeability control element, wherein the at least one permeability control element is configured to be substantially fluid impermeable when the temperature of the at least one permeability control element is less than the permeability transition temperature of the at least one permeability control element, and wherein the at least one permeability control element is disposed within the outer airflow channel, the at least one permeability control element being configured to prevent fluid flow along the outer airflow channel downstream of the permeability control element when the temperature of the at least one permeability control element is less than the permeability transition temperature of the at least one permeability control element, and to allow fluid flow along the outer airflow channel downstream of the permeability control element when the temperature of the at least one permeability control element is equal to or greater than the permeability transition temperature of the at least one permeability control element.

The at least one permeability control element may facilitate adjusting an amount of airflow along the outer airflow channel. The at least one permeability control element may advantageously allow for adjusting the suction resistance of the aerosol-generating article. The at least one permeability control element may advantageously be used to tailor the amount of airflow provided with the flavor substrate. Thus, the at least one permeability control element may improve customization of the user experience.

The flavor substrate may be a permeability control element. The flavor substrate may be the permeability control element. The permeability control element may be the flavor substrate. This may allow for an optimized design of the aerosol-generating article, wherein the flavour matrix also contributes to regulating the airflow within the outer airflow channel. The aerosol-generating article may comprise only one permeability control element. When the aerosol-generating article comprises only one permeability control element, the flavour matrix may be the only permeability control element.

The aerosol-generating article may comprise more than one permeability control element. When the aerosol-generating article comprises more than one permeability control element, the flavour matrix may be one of the more than one permeability control elements. When the aerosol-generating article comprises more than one permeability control element, the permeability transition temperatures of the more than one permeability control element may be substantially the same temperature. Also, when the aerosol-generating article comprises more than one permeability control element, the more than one permeability control elements may have different permeability transition temperatures relative to each other.

The at least one permeability control element may be configured to prevent fluid flow along the outer gas flow channel downstream of the permeability control element when the temperature of the at least one permeability control element is at least 20 degrees celsius and to allow fluid flow along the outer gas flow channel downstream of the permeability control element when the temperature of the at least one permeability control element is at least 85 degrees celsius.

It may be desirable for the permeability control element to be substantially fluid impermeable at 20 degrees celsius and fluid permeable at 85 degrees celsius to enable adjustment of the airflow within the external airflow channel using an aerosol-generating device.

The transmittance transition temperature of the at least one transmittance controlled element may be between 70 degrees celsius and 80 degrees celsius.

The at least one permeability control element may comprise a gel composition. The gel composition of the at least one permeability control element can be according to any of the gel compositions described herein. The gel composition of the at least one permeability control element may be free of nicotine or flavor according to any of the gel compositions described herein. The gel composition that is not the at least one permeability control element of the flavor matrix can be free of nicotine or flavor according to any of the gel compositions described herein.

As detailed above, the gel composition may be useful for providing a desired change in permeability to at least one permeability control element as a function of temperature.

However, other materials than gel compositions may be used which also exhibit a change in permeability as a function of temperature.

Materials such as gel compositions may be thermally reversible.

The permeability transition temperature of the at least one permeability control element can be a phase transition temperature of the at least one permeability control element.

The permeability control element may be disposed downstream of the flavor substrate. Such a configuration may be beneficial to allow for control of the amount of flavor aerosol entrained with the matrix aerosol generated upon heating of the aerosol-forming matrix.

The spanning member may be disposed within the outer airflow channel upstream of the flavor substrate.

The spanning member may be useful for regulating or impeding the flow of the matrix aerosol into the outer airflow channel.

The spanning member may be a permeability control member.

When the spanning member is a permeability control member, the regulation of the flow of the matrix aerosol into the outer airflow channel may be advantageously achieved by varying the permeability of the spanning member.

The flavor matrix may extend longitudinally along the entire outer airflow path. This may make the flavour matrix more versatile to control the modulation of the airflow along the outer airflow channel and to regulate the flow of matrix aerosol into the outer airflow channel.

The outer airflow channel may include an air inlet. As a result, the outer airflow channel may advantageously be used to regulate the flow of outside air into the aerosol-generating article. This may enhance customization of the aerosol that may be inhaled by the user.

The air inlet may be disposed downstream of the spanning member.

By providing the air inlet downstream of the spanning member, the outer airflow channel may be configured to selectively or permanently block the flow of the matrix aerosol into the outer airflow channel. Thus, the outer airflow channel may be configured to specifically regulate the ingress of external air into the aerosol-generating article, and to specifically regulate the flow of the flavor aerosol along the outer airflow channel independent of the flow of the matrix aerosol when the flavor matrix is disposed within the outer airflow channel.

When the spanning member is a permeability control member, the matrix aerosol may be allowed to enter the outer airflow channel. This may help to improve the mixing of the flavour aerosol, the matrix aerosol and the external air to generate an aerosol which is user inhalable.

The tubular element may be disposed immediately downstream of the aerosol-forming substrate.

Such a configuration, in which no intermediate portion is provided between the aerosol-forming substrate and the tubular element, may be beneficial in ensuring that the substrate aerosol generated upon heating of the aerosol-forming substrate more effectively entrains the flavour aerosol generated upon heating of the flavour substrate.

The aerosol-generating article may comprise a filter arranged downstream of the tubular element in the longitudinal direction.

The term "filter" is used to indicate a section of an aerosol-generating article configured to at least partially remove a gas phase or a particulate phase component or both gas and particulate phase components from a mainstream aerosol drawn through the filter.

The filter may be arranged immediately downstream of the tubular element in the longitudinal direction.

Since the tubular element may be useful and sufficient for providing customization of the formed aerosol according to user preferences, the filter may be arranged immediately downstream of the tubular element, i.e. without an intermediate portion such as an aerosol cooling element. Thus, the aerosol-generating article may achieve a reduction in gas and particulate phase components while requiring fewer production steps and allowing for a more consistent experience.

However, the aerosol-generating article may comprise an aerosol-cooling element downstream of the tubular element. Preferably, the aerosol-cooling element may be disposed between the tubular element and the filter.

The aerosol-generating article may comprise a mouthpiece disposed on an upstream end of the aerosol-generating article. It may be desirable to provide a mouthpiece to facilitate inhalation of the aerosol by the user.

The aerosol-generating article may comprise a wrapper defining at least a portion of the aerosol-generating article. Advantageously, such a wrapper may prevent a user from touching the aerosol-forming substrate, which helps to maintain a high level of hygiene. The wrapper may be formed of any suitable material. In particular, the wrapper may be formed from a porous material. The wrapper may be made of a material which allows release of the volatile compounds when the wrapper is disposed about the downstream section of the aerosol-generating article.

Advantageously, the wrapper may hold together a plurality of components of the aerosol-generating article. For example, the wrapper may hold the aerosol-forming substrate and the tubular element together. When the aerosol-generating article comprises a filter, the wrapper may hold the filter and the tubular element together.

Advantageously, providing one or more wrappers may improve the structural integrity of the aerosol-generating article.

The components of the aerosol-generating article may be secured together by any suitable means. For example, the aerosol-generating article may comprise a connection mechanism. The attachment mechanism may help hold the components of the aerosol-generating article together.

When a wrapper defining at least a portion of the aerosol-generating article is provided and the aerosol-generating article comprises the connection mechanism, the wrapper may be configured to exert pressure on the connection mechanism.

The aerosol-forming substrate may have any suitable cross-section. For example, the substrate may have a circular, oval, stadium-shaped, rectangular, or triangular cross-sectional shape. Preferably, the matrix has a circular cross-sectional shape.

The solid aerosol-forming substrate may comprise a tobacco rod. The tobacco rod may include, for example, one or more of the following: a powder, granule, pellet, chip, strand, ribbon or sheet comprising one or more of the following: herb leaves, tobacco ribs, expanded tobacco and homogenized tobacco. As used herein, the term "homogenized tobacco material" refers to a material formed by agglomerating particulate tobacco. Providing a homogenized tobacco material may improve aerosol generation, nicotine content and flavor profile of an aerosol generated during heating of an aerosol-generating article. In particular, the process of manufacturing homogenized tobacco involves grinding tobacco leaves, which more effectively achieve release of nicotine and flavor upon heating. Where the tobacco rod comprises a homogenized tobacco material, the homogenized tobacco material may be in the form of a sheet. As used herein, the term "sheet" refers to a layered element having a width and a length that is substantially greater than its thickness.

The solid aerosol-forming substrate may comprise a homogenized tobacco material. The solid aerosol-forming material may comprise a fragment, strand or ribbon of homogenised tobacco material. The solid aerosol-forming substrate may comprise a sheet of homogenised tobacco material.

The aerosol-forming substrate may have a substantially homogeneous composition. The aerosol-forming substrate may have a substantially homogeneous composition at least in the longitudinal direction.

The sheet of homogenized tobacco material may be formed by agglomerating particulate tobacco obtained by grinding or otherwise pulverizing one or both of tobacco lamina and tobacco stems. The sheet of homogenised tobacco material may comprise one or more of the following: tobacco dust, tobacco fines, and other particulate tobacco by-products formed during, for example, handling, processing, and shipping of tobacco. The sheet of homogenised tobacco material is preferably formed by a casting process of the type generally comprising: casting a slurry comprising particulate tobacco and one or more binders onto a conveyor belt or other support surface; drying the casting slurry to form a sheet of homogenized tobacco material; and removing the sheet of homogenized tobacco material from the support surface.

The solid aerosol-forming substrate may comprise an aggregated sheet of homogenised tobacco material. As used herein, the term "gathered" is used to describe the sheet material being wrapped, folded or otherwise compressed or contracted substantially transverse to the longitudinal axis of the aerosol-generating article.

The aerosol-forming substrate comprises an agglomerated textured sheet of homogenised tobacco material. As used herein, the term "textured sheet" refers to a sheet that has been curled, embossed, gravure, perforated, or otherwise deformed. The use of a textured sheet of homogenised tobacco material may advantageously promote aggregation of the sheet of homogenised tobacco material to form an aerosol-forming substrate. The aerosol-forming substrate may comprise an aggregated textured sheet of homogenised tobacco material comprising a plurality of spaced apart indentations, protrusions, perforations or a combination thereof.

Preferably, the aerosol-forming substrate comprises an aggregated crimped sheet of homogenised tobacco material. As used herein, the term "curled sheet" means a sheet having a plurality of substantially parallel ridges or corrugations. Preferably, the substantially parallel ridges or corrugations extend along or parallel to the longitudinal axis of the aerosol-generating article. This advantageously promotes aggregation of the curled sheets of homogenised tobacco material to form an aerosol-generating article. However, it will be appreciated that the crimped sheet of homogenised tobacco material for inclusion in an aerosol-generating article may have a plurality of substantially parallel ridges or corrugations disposed at an acute or obtuse angle relative to the longitudinal axis of the aerosol-generating article.

The aerosol-forming substrate may comprise tobacco-containing material and tobacco-free material.

The aerosol-forming substrate may comprise an aerosol-former. The aerosol-forming substrate may comprise a single aerosol-former or a combination of two or more aerosol-formers. As used herein, the term "aerosol-former" is used to describe any suitable known compound or mixture of compounds that, in use, promotes the formation of an aerosol and is substantially resistant to thermal degradation at the operating temperature of the aerosol-generating article. Suitable aerosol formers include, but are not limited to: polyols such as propylene glycol, triethylene glycol, 1, 3-butanediol, and glycerol; esters of polyols, such as glycerol mono-, di-or triacetate; and aliphatic esters of mono-, di-or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formers are polyols or mixtures thereof such as propylene glycol, triethylene glycol, 1, 3-butanediol and most preferably glycerol. The aerosol-forming substrate may have an aerosol former content of greater than 5% by dry weight. The aerosol-forming substrate may have an aerosol former content of between about 5% and about 30% on a dry weight basis. The aerosol-forming substrate may have an aerosol former content of about 20% on a dry weight basis.

The aerosol-forming substrate preferably comprises a reconstituted tobacco material, an aerosol-former and water.

The homogenized tobacco material may be provided in a sheet that is one of folded, curled or cut into strips. The sheet may be cut into strips having a width of between about 0.2 mm and about 2 mm, more preferably between about 0.4 mm and about 1.2 mm. The width of the strip may be about 0.9 mm.

The aerosol-forming substrate may comprise an inner cavity. In other words, the aerosol-forming substrate may be a tubular substrate. The aerosol-forming substrate may comprise a substrate inner surface having a substrate inner diameter defining a lumen extending in a longitudinal direction within the aerosol-forming substrate. Providing the lumen into the aerosol-forming substrate may enable the heating element to be inserted into the aerosol-forming substrate in the lumen without penetrating the substrate and without changing the structure of the substrate. The provision of the inner cavity may also be beneficial in further reducing the thickness of the aerosol-forming substrate, thereby enhancing the heat transfer advantages explained above.

When the aerosol-forming substrate comprises a substrate inner surface defining a lumen, the substrate inner surface may have the same cross-sectional shape as the substrate outer surface. In particular, the inner surface of the matrix may have a substantially circular, oval or stadium-shaped cross-section.

The aerosol-generating article may comprise a layer of thermally conductive material. The layer of thermally conductive material may cover at least a portion of at least the otherwise exposed aerosol-forming substrate. The layer of thermally conductive material may be disposed at least on the outer surface of the substrate. The layer of thermally conductive material may be disposed at least on the inner surface of the substrate. The layer of thermally conductive material may be disposed at least on the inner surface of the substrate and on the outer surface of the substrate. Providing a layer of thermally conductive material on the otherwise exposed substrate surface may allow heat from the heating element received by or engaged with the substrate to be distributed over a wider area of the aerosol-forming substrate, thereby improving the heat transfer efficiency between the heating element and the aerosol-forming substrate. The layer of thermally conductive material may also create a physical separation between the heating element received in the inner cavity and the aerosol-forming substrate, which may reduce the risk of overheating of the aerosol-forming substrate in the region of the substrate proximate to the heating element. The layer of thermally conductive material may also increase the robustness of the tubular aerosol-forming substrate, which may be reduced by providing an inner cavity such that the thickness of the substrate is reduced.

As used herein, "thermally conductive" refers to a material having a thermal conductivity of at least 10W/m.k, preferably at least 40W/m.k, more preferably at least 100W/m.k at 23 degrees celsius and 50% relative humidity. Preferably, the layer of thermally conductive material may comprise a material having a thermal conductivity of at least 40W/m.k, preferably at least 100W/m.k, more preferably at least 150W/m.k, and even more preferably at least 200W/m.k at 23 degrees celsius and 50% relative humidity.

Examples of suitable conductive materials include, but are not limited to, aluminum, copper, zinc, nickel, silver, and combinations thereof.

The aerosol-forming substrate may have a strip comprising a plurality of elongate tubular elements. The elongate tubular member may comprise tobacco material. The plurality of elongated tubular elements comprised in the aerosol-forming substrate is never wrong for tubular elements arranged downstream of the aerosol-forming substrate.

By adjusting the number, equivalent diameter and thickness of the elongated tubular elements in the strip, it is possible to advantageously adjust the density and porosity of the strip. Generally, aerosol-forming substrates comprising a plurality of elongate tubular elements of homogenised tobacco may advantageously exhibit a more uniform density compared to aerosol-forming substrates comprising fragments of tobacco material. The geometry of the elongate tubular member may be such as to provide a particularly stable passage for airflow along the strip. This may advantageously allow for consistent fine tuning of the RTD such that an aerosol-forming substrate having a predetermined RTD may be consistently and highly accurately manufactured.

The weight of the aerosol-forming substrate comprising the elongate tubular elements of homogenised tobacco may be determined by the number, size, density and spacing of the tubular elements. This may reduce weight inconsistencies between aerosol-forming substrates of the same size and thus lower the rejection rate of aerosol-forming substrates having a weight falling outside the selected accepted range as compared to aerosol-forming substrates comprising fragments of tobacco material.

The variation in thickness of the elongate tubular member in the rod can also be advantageously used to adjust the content of homogenised tobacco in the rod. For example, in an elongated tubular element formed by a rolled strip of homogenised tobacco web, the adjustment of the thickness of the elongated tubular element may be achieved by varying the number of windings of the strip around the longitudinal axis or by varying the thickness of the homogenised tobacco web itself. This may give the aerosol-generating article greater design flexibility than an aerosol-generating article comprising fragments of tobacco material.

The size, geometry and arrangement of the elongate tubular elements in the strip may be readily adapted to facilitate insertion of the heating element into the strip of aerosol-generating article. Because the elongate tubular member is located substantially straight within the strip and extends longitudinally, insertion of a longitudinally extending internal heating element, such as a heater chip, is facilitated. The regular arrangement of the elongated tubular elements in the strip may also advantageously facilitate optimizing the heat transfer from the heating element through the strip.

Inserting (and removing) the heater of the aerosol-generating device into the aerosol-forming substrate comprising the tobacco material fragments may tend to dislodge the tobacco material fragments from the aerosol-forming substrate. This may require more frequent cleaning of the heater element and other parts of the aerosol-generating device in order to remove dislodged debris. In contrast, inserting and removing a heater of an aerosol-generating device into an aerosol-forming substrate comprising a plurality of elongate tubular elements of homogenised tobacco material may advantageously have a significantly reduced tendency to remove material therefrom.

The strip comprising a plurality of elongated tubular elements may be manufactured in a continuous process which may be efficiently performed at high speed and which may be conveniently deployed into existing production lines for manufacturing aerosol-generating articles.

The strips of aerosol-forming substrate preferably have an outer diameter approximately equal to the outer diameter of the aerosol-generating article.

The strips of aerosol-forming substrate may have an outer diameter of at least 5 mm. The strips of aerosol-forming substrate may have an outer diameter of between about 5 mm and about 12 mm, for example between about 5 mm and about 10 mm or between about 6 mm and about 8 mm. Preferably, the strips of aerosol-forming substrate may have an outer diameter of within 7.2 mm to 10%.

The strips of aerosol-forming substrate may have a length of between about 5 millimeters and about 100 mm. Preferably, the strips of aerosol-generating substrate have a length of at least about 5 mm, more preferably at least about 7 mm. The strips of aerosol-generating substrate preferably have a length of less than about 80 mm, more preferably less than about 65 mm, even more preferably less than about 50 mm. Preferably, the strips of aerosol-generating substrate may have a length of less than about 35 mm, more preferably less than 25 mm, even more preferably less than about 20 mm. The strips of aerosol-forming substrate may have a length of about 10 mm; the strips of aerosol-forming substrate may have a length of about 12 mm.

The strip of aerosol-forming substrate may have a substantially uniform cross-section along the length of the strip. The strips of aerosol-forming substrate may preferably have a substantially circular cross-section.

The strip comprising the elongate tubular member may be defined by a wrapper. The elongate tubular member may be assembled such that the elongate tubular member extends in a longitudinal direction.

The plurality of elongated tubular elements of the rod of aerosol-generating articles according to the invention may be formed from a homogenized tobacco material, which may comprise particulate tobacco obtained by grinding. The plurality of elongate tubular members may all have substantially the same composition as one another. Likewise, the plurality of elongate tubular members may comprise tubular members of at least two different compositions.

The at least one elongate tubular element in the rod may comprise a rolled strip cut from a sheet or web of homogenised tobacco material.

The sheet or web of homogenized tobacco material may have a tobacco content of at least about 40 weight percent by dry weight, more preferably at least about 60 weight percent by dry weight, more preferably at least about 70 weight percent by dry weight, and most preferably at least about 90 weight percent by dry weight.

The sheet or web of homogenised tobacco material for use in the aerosol-forming substrate may comprise one or more intrinsic binders (i.e. tobacco endogenous binders), one or more extrinsic binders (i.e. tobacco exogenous binders) or a combination thereof to assist in coalescing the particulate tobacco. The sheet of homogenized tobacco material for use in an aerosol-forming substrate may comprise other additives including, but not limited to, tobacco and non-tobacco fibers, aerosol-formers, humectants, plasticizers, flavorants, fillers, aqueous and non-aqueous solvents, and combinations thereof.

Suitable extrinsic binders included in sheets or webs of homogenized tobacco material for use in aerosol-forming substrates are known in the art, including, but not limited to: gums such as, for example, guar gum, xanthan gum, acacia gum and locust bean gum; cellulosic binders such as, for example, hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, and ethyl cellulose; polysaccharides such as, for example, starch; organic acids such as alginic acid; conjugate base salts of organic acids such as sodium alginate, agar, and pectin; and combinations thereof.

Suitable non-tobacco fibers included in sheets or webs of homogenized tobacco material for use in aerosol-forming substrates are known in the art, including but not limited to: cellulose fibers; cork fiber; a hardwood fiber; jute fibers and combinations thereof. The non-tobacco fibers may be treated by suitable processes known in the art prior to inclusion in the sheet of homogenized tobacco material for use in an aerosol-forming substrate, including, but not limited to: mechanical pulping; refining; chemical pulping; bleaching; pulping by sulfate; and combinations thereof.

The sheet or web of homogenised tobacco material may comprise an aerosol former.

The sheet or web of homogenised tobacco for use in the aerosol-generating article of the invention may be manufactured by methods known in the art (e.g. as disclosed in international patent application WO-A-2012/164009A 2). A sheet of homogenised tobacco material for use in an aerosol-generating article may be formed from a slurry comprising particulate tobacco, guar gum, cellulose fibres and glycerol by a casting process.

Likewise, an elongate tubular element of homogenised tobacco material for use in an aerosol-forming substrate according to the invention may be formed by extrusion. For example, a slurry comprising particulate tobacco obtained by grinding or otherwise pulverizing tobacco leaf lamina may be pushed through a die having a desired cross-section. Furthermore, additive manufacturing may also be used to manufacture tubular elements of homogenised tobacco material.

The elongate tubular member may have an equivalent diameter of about 0.03 mm to about 3 mm. Preferably, the elongate tubular member may have an equivalent diameter of at least about 0.1 mm. More preferably, the elongate tubular member may have an equivalent diameter of at least about 0.3 millimeters.

Likewise, the elongate tubular member may preferably have an equivalent diameter of less than about 2 millimeters. More preferably, the elongate tubular member may have an equivalent diameter of less than about 1 millimeter.

The elongate tubular member may have an equivalent diameter of about 0.7 millimeters to about 2.7 millimeters; the elongate tubular member may have an equivalent diameter of about 0.3 mm to about 1.1 mm.

In the case of an elongate tubular element formed by rolling up a strip of homogenised tobacco material, the strip may have a width of at least about 1 mm. Preferably, the strip of homogenised tobacco material may have a width of at least about 2 mm. More preferably, the strip of homogeneous material may have a width of at least about 3 millimeters.

The strip of homogenized tobacco material may have a width of about 1 mm to about 3.5 mm; the strip of homogenised tobacco material may have a width of about 2.4 mm to about 8.2 mm.

Strips of homogenized tobacco material may be cut from a sheet or web having a thickness of at least about 40 microns, more preferably at least about 60 microns, more preferably at least about 80 microns and most preferably at least about 100 microns. Likewise, strips of homogenized tobacco material may be cut from a sheet or web having a thickness of no more than about 5000 microns, more preferably no more than about 2000 microns, more preferably no more than about 1000 microns, and most preferably no more than about 500 microns. For example, the thickness of the sheet or web may be between about 40 microns and about 5000 microns, more preferably between about 60 microns and about 2000 microns, more preferably between about 80 microns and about 1000 microns, and most preferably between about 100 microns and about 500 microns.

The thickness of the elongate tubular member may be at least about 40 microns, more preferably at least about 80 microns, more preferably at least about 120 microns, and most preferably at least about 160 microns. Likewise, the thickness of the elongate tubular member may be less than about 5000 microns, more preferably less than about 2500 microns, and most preferably less than about 1000 microns.

The elongate tubular member may be formed of a porous tobacco material such that air flows through the wall of the tubular member; i.e. the air flow in the substantially radial direction in the strip is not hindered. In the case of an elongate tubular element formed by rolling up a strip of homogenised tobacco material, the strip itself may be formed of porous tobacco material.

As used herein with respect to a homogenized tobacco material, the term "porous" may indicate that the tobacco material has been created within an inherent porosity such that sufficient pores or gaps are provided within the structure of the sheet or web, such that air is able to flow through the sheet or web in a direction transverse to the surface of the sheet or web. Likewise, the term "porous" may indicate that each sheet or web of tobacco material includes a plurality of airflow apertures to provide the desired porosity. For example, a sheet of tobacco material may be pierced through the air flow hole pattern prior to performing a rolling operation of the elongate tubular member that produces the strip of aerosol-forming substrate. The air flow holes may be randomly or uniformly perforated in the sheet. The pattern of air flow holes may cover substantially the entire surface of the sheet, or may cover one or more specific areas of the sheet with the remaining areas being devoid of air flow holes.

The strip of homogenised tobacco material from which the elongate tubular member may be formed may be textured. For example, the sheet or web from which the strips are cut may include a plurality of spaced apart indentations, protrusions, perforations, or a combination thereof. The texture may be provided on one side of each sheet or on both sides of each sheet.

The inclusion of one or more elongated tubular elements formed from a crimped ribbon may help to provide and maintain a spacing between adjacent tubular elements within the ribbon.

The additive may be applied to at least a portion of a surface of at least one of the plurality of tubular elements. The additive may be a solid additive, a liquid additive, or a combination of a solid additive and a liquid additive. Suitable solid and liquid additives for use in the present invention are known in the art and include, but are not limited to: fragrances such as, for example, menthol; adsorbents such as activated carbon; fillers such as, for example, calcium carbonate; and (3) a plant additive.

To form a substantially elongate tubular element, a strip of homogenised tobacco material may be wrapped around the longitudinal axis at least about 345 degrees. Preferably, the strip of homogenised tobacco material may be wrapped at least about 360 degrees around the longitudinal axis. More preferably, the strip of homogenized tobacco material may be wrapped at least about 540 degrees about the longitudinal axis. Likewise, the strip of homogenized tobacco material may preferably be wrapped less than about 1800 degrees around the longitudinal axis. More preferably, the strip of homogenised tobacco material may be wrapped less than about 900 degrees about the longitudinal axis. Preferably, the strip of homogenised tobacco material may be wrapped about the longitudinal axis between about 345 degrees and about 540 degrees.

Each elongate tubular member may have a length substantially equal to the length of the strip of aerosol-forming substrate. Each elongate tubular member may have a length of about 10 millimeters; each elongate tubular member may have a length of about 12 mm.

The rod of aerosol-forming substrate may comprise less than about 200 elongate tubular elements of homogenised tobacco material. More preferably, the strip of aerosol-forming substrate may comprise less than about 150 elongate tubular elements. Even more preferably, the strip of aerosol-forming substrate may comprise less than about 100 elongate tubular elements.

Likewise, the rod of aerosol-forming substrate may comprise at least about 15 elongate tubular elements of homogenised tobacco material. More preferably, the strip of aerosol-forming substrate comprises at least about 30 elongate tubular elements. Even more preferably, the strip of aerosol-forming substrate may comprise at least about 40 elongate tubular elements. The rod of aerosol-forming substrate may comprise from about 15 to about 100 strands of non-tobacco material.

In the strip of aerosol-forming substrate, the elongate tubular elements may be aligned substantially parallel to each other.

The elongate tubular element of homogenised tobacco material may have a substantially oval cross-section; it may have a substantially elliptical cross-section; which may have a substantially circular cross-section. As described above, an elongate tubular element for use in an aerosol-generating article may be effectively formed by wrapping a strip of homogenised tobacco material around its longitudinal axis by slightly less than 360 degrees. This effectively results in an element having a C-shaped cross section with the slit extending longitudinally throughout the length of the elongate tubular element.

The plurality of elongate tubular elements forming the strip of aerosol-forming substrate may be defined by a wrapper. The wrapper may be formed from a porous or non-porous sheet material. The package may be formed from any suitable material or combination of materials. The wrapper may be a paper wrapper. Alternatively, the wrapper may be adhered to the outer edges of the plurality of elongate tubular members. For example, at least one of the inner surface of the wrapper and the outer edges of the plurality of elongated tubular elements may be wetted during the production process such that the inner wrapper adheres to the edges of the elongated tubular elements during the packaging process. Likewise, an adhesive may be applied to at least one of the inner surface of the wrapper and the outer edges of the plurality of elongated tubular members upstream of the wrapping step. The adhesion of the plurality of elongate tubular members and the wrapper may advantageously help maintain the position and spacing of the plurality of elongate tubular members within the strip.

The wrapper may be at least partially folded over the elongate tubular members at the upstream and downstream ends of the strip to retain the plurality of elongate tubular members within the strip. The wrapper may cover the periphery of the plurality of elongate tubular members at the upstream and downstream ends of the strip such that the remainder of the elongate tubular members are exposed. The wrapper may cover the entire upstream and downstream ends of the strip.

As described above, separate edge sections of paper or other material may be attached to the wrapper to cover at least the perimeter of the upstream and downstream ends of the elongate tubular member. In the case where the wrapper is folded over the ends of the strip, or where separate edge sections are provided, additional overwrap may be provided, covering the wrapper defining the plurality of elongate tubular elements.

The strips for use in aerosol-generating articles as described above may be manufactured by the following method. In a first step of the method, a sheet or web of homogenised tobacco material may be provided. In a second step, an elongate strip having a longitudinal axis may be cut from a sheet or web of homogenised tobacco material. The cutting operation may be performed by feeding the sheet or web from a roll or spool and by moving the sheet or web in a continuous manner along a predetermined direction. The cutting device may be provided at a cutting station to which the web or sheet is fed. For this purpose, a mechanical cutter may be used. Lasers may also be used.

In a third step, the strip may be rolled up, i.e. wound around a longitudinal axis to form an elongated tubular element. This may be achieved by feeding the strip to the funnel-shaped element in a predetermined direction such that the strip is coiled and shaped into a rolled-up elongate tubular element. Several individual rolled elongated tubular elements may be manufactured in parallel.

In a fourth step, the plurality of elongated tubular elements obtained at the end of the third step may be collated and assembled such that the elongated tubular elements extend in the longitudinal direction. This may be achieved by feeding a plurality of elongate tubular elements through another funnel element such that they are grouped into substantially cylindrical clusters.

In a fifth step, the assembled elongate tubular member may be defined with a wrapper to form a continuous strip. In the sixth step, the continuous strip may be cut into a plurality of discontinuous strips.

The method may comprise the further step of applying at least one aerosol former to the sheet or web of homogeneous material prior to the step of cutting the sheet or web to obtain the strip. The method may further comprise the further step of applying at least one aerosol-forming agent to the elongate tubular element prior to the step of finishing and assembling the plurality of elongate tubular members.

Furthermore, the method may comprise the further step of applying at least one aerosol-forming agent to the plurality of elongate tubular elements after the plurality of elongate tubular elements have been collated and assembled. Also, the method may include the step of applying at least one aerosol-forming agent to the plurality of elongate tubular elements after the step of severing the continuous strip into discrete strips.

The method may further comprise the step of drying the homogenized tobacco material after the step of applying the at least one aerosol former.

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 comprising a heater for heating the aerosol-generating article. The heater may include a substrate heating element configured to heat the aerosol-forming substrate and a downstream heating element disposed downstream of the substrate heating element. The downstream heating element may be configured to heat the flavor substrate. The downstream heating element may be configured to heat the at least one permeability control element. The downstream heating element may be configured to heat the spanning element.

As used herein, the term "aerosol-generating system" refers to a combination of an aerosol-generating device and an aerosol-generating article.

Since the aerosol-generating system of the present disclosure comprises an aerosol-generating article according to the previous disclosure, the advantages specified above for the aerosol-generating article also apply to the system itself. In particular, upon heating of the aerosol-forming substrate and the flavor substrate, the aerosol-generating device may be used to generate a substrate aerosol and a flavor aerosol, respectively. Depending on the configuration of the aerosol-generating article, the aerosol-generating device may be used to effect a change in the permeability of the flavor substrate, the at least one permeability control element, the spanning element, and any combination thereof.

The matrix heating element and the downstream heating element may be any suitable type of heating element. The matrix heating element may be an internal heating element. The downstream heating element may be an internal heating element. As used herein, the term "internal heating element" refers to a heating element configured to be inserted into an aerosol-forming substrate or flavor substrate. The matrix heating element and the downstream heating element may be elongate heating elements. The elongate heating element may be sheet-shaped. The elongate heating element may be needle-shaped. The elongate heating element may have a tapered shape or at least a tapered end. The elongate heating element may have a tip. The heating element may be conical. The elongate heating element may have any suitable shape arranged to facilitate insertion of the heating element into the aerosol-forming substrate or flavour substrate. Advantageously, the elongate heating element may provide easier engagement or disengagement or both of the aerosol-generating article and the heating element of the device.

The matrix heating element may be an external heating element. The downstream heating element may be an external heating element. As used herein, the term "external heating element" refers to a heating element configured to heat the outer surface of an aerosol-forming substrate or flavor substrate. The at least one external heating element may at least partially define a cavity for receiving an aerosol-forming substrate or flavor substrate.

The heater may comprise at least one resistive heating element.

The matrix heating element may be a resistive heating element, i.e. the heater may comprise a matrix resistive heating element. The downstream heating element may be a resistive heating element, i.e. the heater may comprise a downstream resistive heating element.

The matrix resistive heating element and the downstream resistive heating element may be electrically connected in a parallel arrangement. Advantageously, providing a plurality of resistive heating elements electrically connected in a parallel arrangement may facilitate delivering desired power to the heating elements while reducing or minimizing the voltage required to provide the desired power. Advantageously, reducing or minimizing the voltage required to operate the at least one heating element may facilitate reducing or minimizing the physical size of the power supply.

The at least one resistive heating element may comprise an electrically insulating substrate and one or more electrically conductive tracks on the electrically insulating substrate.

The electrically insulating substrate may be stable at the operating temperature of the at least one heating element. The electrically insulating substrate may be stable at temperatures up to about 400 degrees celsius, more preferably at temperatures of about 500 degrees celsius, more preferably at temperatures of about 600 degrees celsius, more preferably at temperatures of about 700 degrees celsius, and most preferably at temperatures of about 800 degrees celsius.

The operating temperature of the at least one resistive heating element during use may be at least about 200 degrees celsius. The operating temperature of the at least one resistive heating element during use may be less than about 700 degrees celsius. The operating temperature of the at least one resistive heating element during use may be less than about 600 degrees celsius. The operating temperature of the at least one resistive heating element during use may be less than about 500 degrees celsius. The operating temperature of the at least one resistive heating element during use may be less than about 400 degrees celsius.

The electrically insulating substrate may comprise any suitable material. For example, the electrically insulating substrate may comprise one of the followingOr a plurality of: paper, glass, ceramic, anodized metal, coated metal, and polyimide. The ceramic may include mica, alumina (Al ₂ O ₃ ) Or zirconia (ZrO ₂ ). The electrically insulating substrate can have a thermal conductivity of less than or equal to about 40 watts per meter kelvin, preferably less than or equal to about 20 watts per meter kelvin, and desirably less than or equal to about 2 watts per meter kelvin.

Suitable materials for forming the resistive heating element and in particular the one or more conductive tracks may 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 composites made of ceramic materials and metal materials. Such composite materials may include doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbide. Examples of suitable metals include titanium, zirconium, tantalum, and platinum group metals. Examples of suitable metal alloys include stainless steel, alloys containing nickel, cobalt, chromium, aluminum-titanium-zirconium, hafnium, niobium, molybdenum, tantalum, tungsten, tin, gallium, manganese, and iron, and alloys based on nickel, iron, cobalt, stainless steel, And superalloys of iron-manganese-aluminum-based alloys.

The resistive heating element may include one or more stamped portions of resistive material, such as stainless steel. The at least one resistive heating element may comprise a heating wire or filament, such as a Ni-Cr (nickel-chromium), platinum, tungsten or alloy wire.

The heater may comprise at least one induction heating means.

The substrate heating element may be an induction heating device, i.e. the heater may comprise a substrate induction heating device. The downstream heating element may be an induction heating device, i.e. the heater may comprise a downstream induction heating device.

The at least one induction heating means may comprise at least one inductor coil. The at least one induction heating means may comprise a matrix inductor coil. The at least one induction heating means may comprise a downstream inductor coil. The inductor coil is arranged to generate a varying magnetic field upon receiving a varying current from the power supply. Such varying current may be between about 5 kilohertz and about 500 kilohertz. The varying current may be a high frequency varying current. As used herein, the term "high frequency varying current" refers to a varying current having a frequency between about 500 kilohertz and about 30 megahertz. The high frequency varying current may have a frequency between about 1 megahertz and about 30 megahertz (such as between about 1 megahertz and about 10 megahertz, or such as between about 5 megahertz and about 8 megahertz). The varying current may be an alternating current that generates an alternating magnetic field.

The inductor coil may have any suitable form. For example, the inductor coil may be a flat inductor coil. The flat inductor coil may be wound in a spiral manner substantially in a plane. Preferably, the inductor coil may be a tubular inductor coil. Typically, the tubular inductor coil may be helically wound about the longitudinal axis. The inductor coil may be elongate. Particularly preferably, the inductor coil may be an elongated tubular inductor coil. The inductor coil may have any suitable cross-section. For example, the inductor coil may have a circular, oval, square, rectangular, triangular, or other polygonal cross-section.

The inductor coil may be formed of any suitable material. The inductor coil may be formed of a conductive material. Preferably, the inductor coil may be formed of a metal or metal alloy.

As used herein, "electrically conductive" refers to a material having a resistivity of less than or equal to 1x10 "4 ohm-meters (Ω -m) at twenty degrees celsius.

The at least one induction heating means may comprise at least one susceptor. The at least one induction heating means may comprise a substrate susceptor. The at least one induction heating device may comprise a downstream susceptor. As used herein, the term "susceptor" refers to an element comprising a material capable of converting magnetic energy into heat. The susceptor is heated when it is in a varying magnetic field, such as the varying magnetic field generated by an inductor coil. For example, the substrate susceptor may be heated when the substrate susceptor is located in a varying magnetic field generated by the substrate inductor coil; the downstream susceptor may be heated when the downstream susceptor is in a varying magnetic field generated by a downstream inductor coil.

Heating of the susceptor may be a result of hysteresis losses and/or eddy currents induced in the susceptor, depending on the electrical and magnetic properties of the susceptor material. In ferromagnetic or ferrimagnetic susceptor materials, hysteresis losses occur as a result of magnetic domains within the material being switched under the influence of a varying electromagnetic field. Eddy currents can be induced if the susceptor material is electrically conductive. In the case of conductive ferromagnetic or ferrimagnetic susceptor materials, heat may be generated due to both eddy currents and hysteresis losses. Thus, the susceptor may be heatable due to at least one of hysteresis loss or eddy currents, depending on the electrical and magnetic properties of the susceptor material.

The susceptor is arranged such that when the aerosol-generating article is received in the aerosol-generating device, the oscillating electromagnetic field generated by the inductor coil may induce an electric current in the susceptor, thereby causing the susceptor to heat up. Preferably, the aerosol-generating device may be capable of generating a fluctuating electromagnetic field having a magnetic field strength (H field strength) of between 1 kiloamp per meter and 5 kiloamps per meter (kA/m), preferably between 2kA/m and 3kA/m, for example about 2.5 kA/m. Preferably, the aerosol-generating device may be capable of generating a fluctuating electromagnetic field having a frequency between 1MHz and 30MHz, for example between 1MHz and 10MHz, for example between 5MHz and 7 MHz.

The susceptor may comprise any suitable material. The susceptor may be formed of any material capable of being inductively heated to a temperature sufficient to release volatile compounds from the aerosol-forming substrate or flavor substrate. Preferred susceptors may be heated to a temperature in excess of about 250 degrees celsius. Preferred susceptors may be formed of an electrically conductive material. Suitable materials for the susceptor include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel-containing compounds, titanium, and composites of metallic materials. Preferred susceptors may comprise metal or carbon. Some preferred susceptors may include ferromagnetic materials, such as ferrite iron, ferromagnetic alloys (such as ferromagnetic steel or stainless steel), ferromagnetic particles, and ferrite. Some preferred susceptors may be composed of ferromagnetic materials. Suitable susceptors may include aluminum. Suitable susceptors may be composed of aluminum. The susceptor may comprise at least about 5%, at least about 20%, at least about 50%, or at least about 90% ferromagnetic or paramagnetic material.

Preferably, the susceptor may be formed of a substantially gas impermeable material. In other words, preferably, the susceptor may be formed of a gas impermeable material.

The susceptor may have any suitable form. For example, the susceptor may be elongate. The susceptor may have any suitable cross-section. For example, the susceptor may have a circular, oval, square, rectangular, triangular, or other polygonal cross-section. The susceptor may be tubular.

The susceptor may comprise a susceptor layer disposed on a support. Placement of the susceptor in a varying magnetic field induces eddy currents in close proximity to the susceptor surface, an effect known as the skin effect. Thus, it is possible to form the susceptor from a relatively thin susceptor material layer while ensuring that the susceptor is effectively heated in the presence of a varying magnetic field. Manufacturing susceptors from a support and a relatively thin susceptor layer may facilitate the manufacture of simple, inexpensive, and robust aerosol-generating articles.

The support may be formed of a material that is not susceptible to induction heating. Advantageously, this may reduce heating of the surface of the susceptor not in contact with the aerosol-forming substrate, wherein the surface of the support forms the surface of the susceptor not in contact with the aerosol-forming substrate.

The support may comprise an electrically insulating material. As used herein, "electrically insulating" refers to a material having a resistivity of at least 1 x 104 ohm-meters (Ω -m) at twenty degrees celsius.

Forming the support from a thermally insulating material may provide a thermally insulating barrier between the susceptor layer and other components of the induction heating apparatus, such as an inductor coil defining an induction heating element. Advantageously, this may reduce heat transfer between the susceptor and other components of the induction heating system.

The thermal insulation material may also have a thickness of less than or equal to about 0.01 square centimeters per second (cm) ² /s) as measured using a laser flash method. Providing a film having such thermal diffusivityCan cause a support having a high thermal inertia, which can reduce heat transfer between the susceptor layer and the support, and reduce temperature variations of the support.

The susceptor may be provided with a protective outer layer, such as a protective ceramic layer or a protective glass layer. The protective outer layer may improve the durability of the susceptor and facilitate cleaning of the susceptor. The protective outer layer may substantially surround the susceptor. The susceptor may include a protective coating formed of glass, ceramic, or an inert metal.

The susceptor may be of any suitable size. The susceptor may have a length of between about 5 mm and about 15 mm, for example between about 6 mm and about 12 mm, or between about 8 mm and about 10 mm. The susceptor may have a width of between about 1 mm and about 8 mm, for example between about 3 mm and about 5 mm. The susceptor may have a thickness of between about 0.01 mm and about 2 mm. Where the susceptor has a constant cross-section (e.g., a circular cross-section), the susceptor may have a preferred width or diameter of between about 1 millimeter and about 5 millimeters.

The susceptor may be located in the device cavity. The susceptor may extend into the device cavity in a longitudinal direction of the device cavity. The susceptor may be elongate. The elongate susceptor may be sheet-shaped. The elongate susceptor may be needle-shaped. The elongate susceptor may have a tapered shape or at least a tapered end. The elongate susceptor may have a tip. The elongate element may be conical.

The substrate susceptor may be an internal heating element configured to be at least partially inserted into an aerosol-forming substrate of the aerosol-generating article when the aerosol-generating article is received in the device cavity. In case the aerosol-forming substrate comprises an inner cavity, the substrate susceptor may be configured to be at least partially inserted into the inner cavity of the aerosol-forming substrate when the aerosol-generating article is received in the device cavity.

The downstream susceptor may be an internal heating element configured to be at least partially inserted into a flavor matrix of the aerosol-generating article when the aerosol-generating article is received in the device cavity.

The substrate susceptor may be an external heating element configured to at least partially define a cavity for receiving an aerosol-forming substrate.

The downstream susceptor may be an external heating element configured to at least partially define a cavity for receiving the flavor substrate.

The induction heating means may comprise at least one internal heating element and at least one external heating element.

The heater may comprise at least one resistive heating element and at least one inductive heating element. The heater may comprise a combination of resistive and inductive heating elements.

The aerosol-generating device may comprise a power supply. The power source may be a DC voltage source. The power source may be a battery. For example, the power source may be a nickel metal hydride battery, a nickel cadmium battery, or a lithium-based battery, such as a lithium cobalt battery, a lithium iron phosphate battery, or a lithium polymer battery. The power source may be another form of charge storage device, such as a capacitor. The power source may need to be recharged and have a capacity that may allow for storing sufficient energy for use of the aerosol-generating device.

A power supply may be electrically connected to the heater for supplying power to heating elements such as the substrate heating element and downstream heating elements. The heating element may generate heat when the heating element receives power from a power source. The power source may be configured to supply sufficient power to the substrate heating element to heat the aerosol-forming substrate to a temperature at which volatile compounds are released from the aerosol-forming substrate. The power source may be configured to supply sufficient power to the downstream heating element to heat the flavor substrate to a temperature that releases the volatile compounds from the flavor substrate. The power source may be configured to supply sufficient power to the downstream heating element to heat the at least one transmittance control element to a temperature at which the at least one transmittance control element is fluid-permeable, i.e., to heat the at least one transmittance control element to its transmittance transition temperature.

The aerosol-generating device may comprise a housing. The housing may at least partially define a cavity for receiving the aerosol-generating article.

The aerosol-generating device may comprise at least one device air inlet in fluid communication with the cavity. When the aerosol-generating device comprises a housing, the housing may at least partially define at least one device air inlet. The housing may define a matrix device air inlet proximate the distal end of the cavity. It may be desirable for the substrate device air inlet to enable ambient air to be drawn into the upstream end of the aerosol-forming substrate. The housing may also define a downstream device air inlet. The downstream device air inlet may be advantageous for enabling ambient air to be drawn into the air inlet of the tubular element. The downstream device air inlet may be configured to substantially match the air inlet of the tubular element when the aerosol-generating article is fully introduced into the cavity for receiving the aerosol-generating article.

The aerosol-generating device may comprise a controller. The controller may be configured to control the supply of electrical power from the power source to the heating element. The controller may be any suitable controller. The controller may include any suitable circuitry and electrical components. The controller may include a processor and a memory. The controller may comprise a microprocessor, which may be a programmable microprocessor.

The aerosol-generating device may comprise a sensor to detect an airflow indicative of the user taking a puff. The airflow sensor may be an electromechanical device. The air flow sensor may be any one of the following: mechanical devices, optical devices, electro-mechanical devices, and microelectromechanical system (MEMS) based sensors. The aerosol-generating device may comprise a manually operable switch for a user to initiate the inhalation.

The aerosol-generating device may comprise an indicator for indicating when the at least one heating element is activated. The indicator may comprise a light that is activated when the at least one heating element is activated.

The aerosol-generating device may comprise at least one electrical connector. The at least one electrical connector may be configured to charge a power source. At least one electrical connector may be configured to connect to another electrical device. The at least one electrical connector may comprise an external plug or socket comprising at least one external electrical contact allowing the aerosol-generating device to be connected to another electrical device. For example, the aerosol-generating device may comprise a USB plug or a USB socket to allow the aerosol-generating device to be connected to another USB-enabled device. For example, a USB plug or socket may allow the aerosol-generating device to be connected to a USB charging device, thereby charging a rechargeable power source within the aerosol-generating device. The USB plug or socket may support data transmission to or from the aerosol-generating device, or both to and from the aerosol-generating device. Also, the aerosol-generating device may be connected to a computer to transmit data to the device, such as a new heating profile for a new aerosol-generating article.

When the aerosol-generating device comprises a USB plug or socket, the aerosol-generating device may further comprise a removable cover covering the USB plug or socket when not in use. When the USB plug or socket is a USB plug, the USB plug may be selectively retracted into the device.

The invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more features of the features of these examples may be combined with any one or more features of another example, embodiment, or disclosure described herein.

Ex1 an aerosol-generating article having an upstream end and a downstream end, the aerosol-generating article defining a longitudinal direction between the upstream end and the downstream end, the aerosol-generating article comprising:

an aerosol-forming substrate;

a tubular element disposed downstream of the aerosol-forming substrate and extending along the longitudinal direction, the tubular element comprising an air inlet; and

a flavor matrix disposed downstream of the air inlet.

Ex2.Ex1 aerosol-generating article wherein the flavor matrix comprises a gel composition.

Ex3. An aerosol-generating article of ex2, wherein the gel composition is configured to be fluid permeable when the temperature of the gel composition is equal to or greater than a transmittance transition temperature of the gel composition, wherein the gel composition is configured to be substantially fluid impermeable when the temperature of the gel composition is below the transmittance transition temperature of the gel composition, and wherein preferably the transmittance transition temperature of the gel composition is a phase transition temperature of the gel composition.

Ex4. An aerosol-generating article of ex3, wherein the transmittance transition temperature of the gel composition is between 70 degrees celsius and 80 degrees celsius.

The aerosol-generating article of any of Ex2 to Ex4, wherein the gel composition is configured to be fluid permeable at 85 degrees celsius, and wherein the gel composition is configured to be substantially fluid impermeable at 20 degrees celsius.

The aerosol-generating article of any one of Ex2 to Ex5, wherein the gel composition is thermally reversible.

An aerosol-generating article according to any one of Ex2 to Ex6, wherein the resistance to draw of the aerosol-generating article when the gel composition is fluid permeable is at least about 10mm H greater than the resistance to draw of the aerosol-generating article when the gel composition is substantially fluid impermeable ₂ O。

Ex8.Ex7 aerosol-generating article, wherein the suction resistance of the aerosol-generating article when the gel composition is fluid permeable is at least about 20mm H greater than the suction resistance of the aerosol-generating article when the gel composition is substantially fluid impermeable ₂ O。

Ex9.Ex8 aerosol-generating article, wherein the suction resistance of the aerosol-generating article when the gel composition is fluid permeable is at least about 30mm H greater than the suction resistance of the aerosol-generating article when the gel composition is substantially fluid impermeable ₂ O。

An aerosol-generating article according to any one of Ex2 to Ex9, wherein the aerosol-generating article has a suction resistance of greater than about 20mm H when the gel composition is substantially fluid impermeable ₂ O, preferably greater than about 30mm H ₂ O, more preferably greater than about 40mm H ₂ O, even morePreferably greater than about 50mm H ₂ O, most preferably greater than about 60mm H ₂ O。

The aerosol-generating article of any one of Ex2 to Ex10, wherein the aerosol-generating article has a suction resistance of less than about 50mm H when the gel composition is fluid permeable ₂ O, more preferably less than about 40mm H ₂ O, even more preferably less than about 30mm H ₂ O, even more preferably less than about 20mm H ₂ O, most preferably less than about 10mm H ₂ O。

The aerosol-generating article of any of Ex2 to Ex11, wherein the gel composition comprises preferably from about 0.1% to about 4%, more preferably from about 0.1% to 2% nicotine.

The aerosol-generating article of any one of Ex2 to Ex12, wherein the gel composition comprises a flavoring.

An aerosol-generating article of ex14.ex13, wherein the flavoring agent comprises one or more of menthol, a coffee-derived flavoring agent comprising caffeine, guarana, taurine and glucuronolactone.

The aerosol-generating article of any of Ex2 to Ex14, wherein the gel composition comprises preferably from about 50% to about 75%, more preferably from about 50% to about 65%, of glycerol.

The aerosol-generating article of any one of Ex2 to Ex15, wherein the gel composition comprises preferably from about 15% to about 35%, more preferably from about 18% to about 32%, even more preferably from about 20% to about 30%, most preferably from about 21% to about 27% Hydroxic Poly Metyl Cellulose (HPMC).

The aerosol-generating article of any one of Ex2 to Ex16, wherein the gel composition comprises preferably from about 3% to about 10%, more preferably from about 4% to about 7% agar.

The aerosol-generating article of any of Ex2 to Ex17, wherein the gel composition comprises preferably from about 0.1% to about 12%, more preferably from about 0.1% to 7% of fibers.

The aerosol-generating article of any of Ex2 to Ex18, wherein the gel composition comprises preferably from about 0.1% to about 9%, more preferably from about 0.1% to 7% of low methoxy (E440 i) pectin.

The aerosol-generating article of any of Ex2 to Ex19, wherein the gel composition comprises preferably from about 1.7% to about 3.1%, more preferably from about 2.1% to about 2.9% lactic acid.

The aerosol-generating article of any one of Ex2 to Ex20, wherein the gel composition comprises preferably about 0.1% to about 7%, more preferably about 0.1% to about 3% Ca lactate.

The aerosol-generating article of any one of Ex2 to Ex21, wherein the gel composition comprises a cannabinoid compound.

The aerosol-generating article of any one of Ex2 to Ex22, wherein the gel composition is uniformly distributed in the flavor matrix.

The aerosol-generating article of any one of Ex2 to Ex22, wherein the gel composition is variably distributed in the flavor matrix.

The aerosol-generating article of any one of Ex2 to Ex24, wherein the gel composition has a viscosity of about 1,000,000 to about 1 pascal per second, preferably 100,000 to 10 pascals per second, preferably 10,000 to 1,000 pascals per second, preferably 1,000 to 100 pascals per second, preferably 500 to 200 pascals per second.

Ex26.Ex1 aerosol-generating article wherein the flavor substrate comprises a flavor substance.

An aerosol-generating article of ex27.ex26, wherein the flavour substance is configured to be fluid-permeable when the temperature of the flavour substance is equal to or greater than a permeability transition temperature of the flavour substance, wherein the flavour substance is configured to be substantially fluid-impermeable when the temperature of the flavour substance is below the permeability transition temperature of the flavour substance, and wherein preferably the permeability transition temperature of the flavour substance is a phase transition temperature of the flavour substance.

An aerosol-generating article of ex28.ex27, wherein the transmittance transition temperature of the flavor substance is between 70 degrees celsius and 80 degrees celsius.

The aerosol-generating article of any one of Ex26 to Ex28, wherein the flavour substance is configured to be fluid permeable at 85 degrees celsius, and wherein the flavour substance is configured to be substantially fluid impermeable at 20 degrees celsius.

The aerosol-generating article of any one of Ex26 to Ex29, wherein the flavour substance is thermally reversible.

An aerosol-generating article according to any one of Ex26 to Ex30, wherein the resistance to draw of the aerosol-generating article when the flavour material is fluid-permeable is at least about 10mm H greater than the resistance to draw of the aerosol-generating article when the flavour material is substantially fluid-impermeable ₂ O。

An aerosol-generating article of ex32.ex31, wherein the resistance to draw of the aerosol-generating article when the flavour material is fluid-permeable is at least about 20mm H greater than the resistance to draw of the aerosol-generating article when the flavour material is substantially fluid-impermeable ₂ O。

An aerosol-generating article of ex33.ex32, wherein the resistance to draw of the aerosol-generating article when the flavour material is fluid permeable is at least about 30mm H greater than the resistance to draw of the aerosol-generating article when the flavour material is substantially fluid impermeable ₂ O。

An aerosol-generating article according to any one of Ex26 to Ex33, wherein the aerosol-generating article has a suction resistance of greater than about 20mm H when the flavour substance is substantially fluid impermeable ₂ O, more preferably greater than about 30mm H ₂ O, even more preferably greater than about 40mm H ₂ O, even more preferably greater than about 50mm H ₂ O, most preferably greater than about 60mm H ₂ O。

The aerosol-generating article of any one of Ex26 to Ex34, wherein the aerosol-generating article has a pull-up resistance of less than about 50mm H when the flavour substance is fluid permeable ₂ O, more preferably less than about 40mm H ₂ O, even more preferably less than about 30mm H ₂ O, even more preferably less than about 20mm H ₂ O, most preferably less than about 10mm H ₂ O。

The aerosol-generating article of any one of Ex26 to Ex35, wherein the flavour substance comprises preferably from about 0.1% to about 4%, more preferably from about 0.1% to 2% nicotine.

The aerosol-generating article of any one of Ex26 to Ex36, wherein the flavour substance comprises a flavouring.

An aerosol-generating article of ex 38.37, wherein the flavoring comprises one or more of menthol, coffee-derived flavoring comprising caffeine, guarana, taurine, and glucuronolactone.

The aerosol-generating article of any one of Ex26 to Ex38, wherein the flavour material comprises preferably from about 50% to about 75%, more preferably from about 50% to about 65%, of glycerol.

The aerosol-generating article of any one of Ex26 to Ex39, wherein the flavour material comprises Hydroxic Poly Metyl Cellulose (HPMC) preferably in the range of about 15% to about 35%, more preferably in the range of about 18% to about 32%, even more preferably in the range of about 20% to about 30%, most preferably in the range of about 21% to about 27%.

The aerosol-generating article of any one of Ex26 to Ex40, wherein the flavour substance comprises preferably about 3% to about 10%, more preferably about 4% to about 7% agar.

The aerosol-generating article of any one of Ex26 to Ex41, wherein the flavour substance comprises preferably from about 0.1% to about 12%, more preferably from about 0.1% to 7% fibres.

The aerosol-generating article of any one of Ex26 to Ex42, wherein the flavour material comprises preferably from about 0.1% to about 9%, more preferably from about 0.1% to 7% of low methoxy (E440 i) pectin.

The aerosol-generating article of any one of Ex26 to Ex43, wherein the flavour substance comprises preferably from about 1.7% to about 3.1%, more preferably from about 2.1% to about 2.9% lactic acid.

The aerosol-generating article of any one of Ex26 to Ex44, wherein the flavour material comprises preferably about 0.1% to about 7%, more preferably about 0.1% to about 3% Ca lactate.

The aerosol-generating article of any one of Ex26 to Ex45, wherein the flavour substance comprises a cannabinoid compound.

The aerosol-generating article of any of Ex26 to Ex46, wherein the flavour substance comprises hydroxypropyl methylcellulose, carboxymethyl cellulose, cellulose-based enhancers, or any combinations thereof, preferably in a content by weight percentage, as disclosed in the above description.

The aerosol-generating article of any of Ex26 to Ex47, wherein the flavour substance comprises a cellulose-based enhancer, and wherein the cellulose-based enhancer comprises cellulose fibres, microcrystalline cellulose, cellulose powder, or any combination thereof, preferably in a content by weight percentage, as disclosed in the above description.

The aerosol-generating article of any of Ex49.ex1 to Ex48, wherein the flavor substrate has a deformation resistance of between about 0.5kgf and about 3kgf, preferably between about 1.3kgf and about 2.7kgf, more preferably between about 1.9kgf and about 2.5 kgf.

The aerosol-generating article of any one of Ex1 to Ex49, wherein the flavour matrix comprises an outer layer.

An aerosol-generating article of ex51.ex50, wherein the outer layer is made of the same material as the remainder of the flavour matrix.

The aerosol-generating article of any one of Ex1 to Ex51, wherein the distance between the upstream end of the aerosol-forming substrate and the downstream end of the flavour substrate is less than about 40 mm, preferably less than about 30 mm, even more preferably less than 20 mm.

The aerosol-generating article of any of Ex1 to Ex52, further comprising an adjustment member disposed on and movable relative to the tubular element such that the adjustment member is configured to change the size of the air inlet.

An aerosol-generating article of ex54, ex53, wherein the adjustment member and the tubular element are linearly movable relative to each other.

An aerosol-generating article of ex55, ex53, wherein the adjustment member and the tubular element are configured to rotate relative to each other.

Ex56. an aerosol-generating article of ex53, wherein the adjustment member and the tubular element are configured to rotate and to move linearly relative to each other, e.g. by means of threads.

An aerosol-generating article according to any one of Ex1 to Ex56, wherein the tubular element comprises an inner tube and an outer tube, the outer tube being arranged around the inner tube, wherein an outer gas flow channel is longitudinally delimited by the inner tube and the outer tube, wherein an inner gas flow channel is longitudinally delimited by the inner tube, and wherein at least the inner gas flow channel is adapted for a matrix aerosol to flow towards the downstream end.

An aerosol-generating article of ex58.ex57, wherein the flavor substrate is disposed within the outer airflow channel.

The aerosol-generating article of any of Ex59.Ex57 to Ex58, further comprising at least one permeability control element,

wherein the at least one permeability control element is configured to be fluid permeable when the temperature of the at least one permeability control element is equal to or greater than the permeability transition temperature of the at least one permeability control element, wherein preferably the permeability transition temperature of the at least one permeability control element is the phase transition temperature of the at least one permeability control element,

wherein the at least one permeability control element is configured to be substantially fluid impermeable when the temperature of the at least one permeability control element is below the permeability transition temperature of the at least one permeability control element,

And wherein the at least one permeability control element is disposed within the outer gas flow channel, the at least one permeability control element being configured to prevent fluid flow along the outer gas flow channel downstream of the permeability control element when the temperature of the at least one permeability control element is below the permeability transition temperature of the at least one permeability control element, and to allow fluid flow along the outer gas flow channel downstream of the permeability control element when the temperature of the at least one permeability control element is equal to or greater than the permeability transition temperature of the at least one permeability control element.

The aerosol-generating article of any of Ex57 to Ex59, further comprising at least one permeability control element,

wherein the at least one transmittance controlled member is configured to be fluid permeable when the at least one transmittance controlled member has a temperature of 85 degrees celsius,

wherein the at least one permeability control element is configured to be substantially fluid impermeable when the at least one permeability control element is at a temperature of 20 degrees celsius,

and wherein the at least one transmittance control element is disposed within the outer gas flow passage, the at least one transmittance control element being configured to prevent fluid flow along the outer gas flow passage downstream of the transmittance control element when the temperature of the at least one transmittance control element is 20 degrees celsius and to allow fluid flow along the outer gas flow passage downstream of the transmittance control element when the temperature of the at least one transmittance control element is 85 degrees celsius.

The aerosol-generating article of any one of Ex59 to Ex60, wherein the at least one permeability control element comprises a gel composition.

The aerosol-generating article of any one of Ex59 to Ex61, wherein the at least one permeability control element comprises a thermoreversible material, such as a thermoreversible gel composition.

The aerosol-generating article of any one of Ex58 and Ex59 to Ex62, wherein the flavour matrix is a permeability control element.

An aerosol-generating article according to any one of Ex64, ex59 to Ex63, wherein the permeability control element is disposed downstream of the flavour matrix.

The aerosol-generating article of any one of Ex59 to Ex64, further comprising a spanning element disposed within the outer airflow channel upstream of the flavor substrate.

An aerosol-generating article of ex66.ex65, wherein the spanning element is a permeability control element.

An aerosol-generating article of ex67.ex63, wherein the flavor matrix extends longitudinally along the entire airflow channel.

An aerosol-generating article of Ex68, ex65 or Ex66, wherein the outer airflow channel comprises the air inlet, and the air inlet is disposed downstream of the spanning element.

An aerosol-generating article according to any one of Ex1 to Ex68, wherein the tubular element is arranged immediately downstream of the aerosol-forming substrate in the longitudinal direction.

The aerosol-generating article of any of Ex1 to Ex69, further comprising a filter disposed downstream of the tubular element.

An aerosol-generating article of ex71.Ex70, wherein the filter is arranged immediately downstream of the tubular element in the longitudinal direction.

The aerosol-generating article of any one of Ex1 to Ex70, further comprising an aerosol-cooling element disposed downstream of the tubular element in the longitudinal direction.

Ex73 an aerosol-generating article of Ex72 when dependent on Ex70, wherein the aerosol-cooling element is disposed between the tubular element and the filter.

The aerosol-generating article of any of Ex74, ex1 to Ex73, further comprising a wrapper defining at least a portion of the aerosol-generating article.

The aerosol-generating article of any of Ex75, ex1 to Ex74, further comprising a connection mechanism configured to hold two or more components of the aerosol-generating article together.

The aerosol-generating article of any one of Ex1 to Ex75, wherein the aerosol-forming substrate comprises a liquid component.

The aerosol-generating article of any one of Ex1 to Ex76, wherein the aerosol-forming substrate comprises a solid component.

The aerosol-generating article of any one of Ex1 to Ex77, wherein the aerosol-forming substrate comprises a plant-based material, preferably comprises a homogenous plant-based material.

The aerosol-generating article of any one of Ex1 to Ex78, wherein the aerosol-forming substrate comprises a non-tobacco material.

An aerosol-generating article of Ex80, ex78 or Ex79, wherein the aerosol-forming substrate comprises tobacco material.

An aerosol-generating article of ex81.Ex80, wherein the aerosol-forming substrate comprises a solid homogenized tobacco material.

An aerosol-generating article of ex82.ex81, wherein the aerosol-forming substrate comprises at least one aggregated sheet of solid homogenized tobacco material.

Ex83.Ex82 aerosol-generating article, wherein the at least one aggregated sheet comprises a textured sheet, a curled sheet, or both.

An aerosol-generating article according to any one of Ex81 to Ex83, wherein the solid homogenised tobacco material comprises a strip of tobacco material.

Ex85 the aerosol-generating article of any one of Ex77 to Ex84 when dependent on Ex77, wherein the aerosol-forming substrate has a strip comprising a plurality of elongate tubular elements.

Ex86 an aerosol-generating article of Ex85 when dependent on Ex81, wherein the plurality of elongate tubular elements comprises solid homogenized tobacco material.

Ex87. An aerosol-generating article of ex86, wherein the at least one elongate tubular material comprises a rolled strip cut from a sheet or web of solid homogenized tobacco material.

The aerosol-generating article of any one of Ex1 to Ex87, wherein the aerosol-forming substrate is a hollow tubular substrate defining an inner cavity.

The aerosol-generating article of any of Ex1 to Ex88, further comprising a layer of thermally conductive material.

The aerosol-generating article of any one of Ex1 to Ex89, wherein the aerosol-forming substrate comprises an aerosol-former.

Ex91 an aerosol-generating device comprising a heater comprising a substrate heating element configured to heat the aerosol-generating article and a downstream heating element disposed downstream of the substrate heating element.

Ex92. an aerosol-generating device of ex91, wherein the heater comprises at least one resistive heating element.

An aerosol-generating device of ex93. 92, wherein the at least one resistive heating element comprises an electrically insulating substrate and one or more electrically conductive tracks on the electrically insulating substrate.

An aerosol-generating device according to any one of Ex91 to Ex93, wherein the heater comprises at least one induction heating device, each induction device comprising at least one inductor coil and at least one susceptor.

An aerosol-generating device of ex95, wherein the at least one inductor coil is arranged to generate a varying magnetic field upon receiving a varying current from a power supply, the varying current being between about 5 kilohertz and about 500 kilohertz.

An aerosol-generating device of ex94, wherein the at least one inductor coil is arranged to generate a varying magnetic field upon receiving a varying current from a power supply, the varying current being between about 500 kilohertz and about 5 megahertz.

The aerosol-generating device of any of Ex94 to Ex96, wherein the at least one inductor coil is a flat inductor coil, such as a flat inductor coil wound in a spiral manner substantially in a plane.

The aerosol-generating device of any of Ex94 to Ex96, wherein the at least one inductor coil is a tubular inductor coil, such as a tubular inductor coil helically wound about a longitudinal axis.

The aerosol-generating device of any one of Ex94 to Ex98, wherein the at least one inductor coil is formed from an electrically conductive material.

The aerosol-generating device of any one of Ex94 to Ex99, wherein the at least one susceptor is formed of an electrically conductive material.

The aerosol-generating device of any of Ex101, ex94 to Ex100, wherein the at least one susceptor comprises a susceptor layer disposed on a support, the support preferably comprising a thermally insulating material.

The aerosol-generating device of any of Ex102 to Ex101, wherein the heater comprises at least one resistive heating element and at least one inductive heating element.

The aerosol-generating device of any of Ex103 to Ex102, wherein the substrate heating element is a substrate induction heating device comprising a substrate inductor coil and a substrate susceptor.

Ex104. An aerosol-generating device of ex103, wherein the downstream heating element is a downstream induction heating device comprising a downstream inductor coil and a downstream susceptor.

Ex105. An aerosol-generating device of ex103, wherein the downstream heating element is a resistive heating element.

The aerosol-generating device of any of Ex106, ex91 to Ex102, wherein the matrix heating element is a resistive heating element.

Ex107. An aerosol-generating device of ex106, wherein the downstream heating element is a resistive heating element.

An aerosol-generating device of ex108.ex106, wherein the downstream heating element is a downstream induction heating device comprising a downstream inductor coil and a downstream susceptor.

The aerosol-generating device of any one of Ex91 to Ex102, wherein the downstream heating element is a downstream induction heating device comprising a downstream inductor coil and a downstream susceptor.

An aerosol-generating device of ex110.ex109, wherein the substrate heating element is a substrate induction heating device comprising a substrate inductor coil and a substrate susceptor.

Ex111. An aerosol-generating device of ex109, wherein the matrix heating element is a resistive heating element.

The aerosol-generating device of any of Ex112, ex91 to Ex102, wherein the downstream heating element is a resistive heating element.

An aerosol-generating device of ex113.Ex112, wherein the substrate heating element is a substrate induction heating device comprising a substrate inductor coil and a substrate susceptor.

Ex114.Ex112 aerosol-generating device, wherein the matrix heating element is a resistive heating element.

The aerosol-generating device of any of Ex115.Ex91 to Ex114, wherein the heater comprises an internal heating element.

The aerosol-generating device of any of Ex116, ex91 to Ex115, wherein the heater comprises an external heating element.

The aerosol-generating device of any of Ex115 or Ex116, wherein the downstream heating element and the matrix heating element are internal heating elements.

Ex115 or Ex116, wherein said downstream heating element and said matrix heating element are external heating elements.

Ex115 or Ex116 aerosol-generating device, wherein the downstream heating element is an internal heating element and the matrix heating element is an external heating element.

The aerosol-generating device of any of Ex115 or Ex116, wherein the downstream heating element is an external heating element and the matrix heating element is an internal heating element.

The aerosol-generating device of any of Ex121, ex91 to Ex120, further comprising a power supply.

An aerosol-generating device of ex122.ex121, wherein the power supply is electrically connected to the heater.

The aerosol-generating device of any one of Ex91 to Ex122, further comprising a cavity for receiving the aerosol-generating article.

The aerosol-generating device of any one of Ex91 to Ex123, further comprising a device housing.

Ex125.Ex123 and Ex124 aerosol-generating devices, wherein the device housing at least partially defines the cavity for receiving the aerosol-generating article.

The aerosol-generating device of any one of Ex91 to Ex125, further comprising at least one device air inlet.

Ex127 an aerosol-generating device of Ex126 when dependent on Ex124, wherein the device housing comprises the at least one device air inlet.

An aerosol-generating device of Ex128, ex126 or Ex127, wherein the at least one device air inlet comprises a matrix device air inlet.

The aerosol-generating device of any one of Ex129, ex126 to Ex128, wherein the at least one device air inlet comprises a downstream device air inlet.

The aerosol-generating article of any one of Ex130, ex91 to Ex129, further comprising a controller.

The aerosol-generating article of any of Ex131, ex91 to Ex130, further comprising a sensor configured to detect an airflow indicative of user inhalation.

The aerosol-generating article of any of Ex132 to Ex131, further comprising at least one electrical connector.

An aerosol-generating article of ex133.ex132, wherein the at least one electrical connector comprises an external plug or socket, such as a USB plug or socket.

Ex134 an aerosol-generating system comprising an aerosol-generating article of any of Ex1 to Ex90 and an aerosol-generating device of any of Ex91 to Ex133.

Drawings

These and other features and advantages of the invention will become more apparent from the following detailed description of a preferred embodiment, given by way of illustrative and non-limiting example only, with reference to the accompanying drawings:

Fig. 1 depicts a longitudinal section of an aerosol-generating article comprising an air inlet in a tubular element.

Fig. 2 shows the aerosol-generating article of fig. 1 at a time when the aerosol-forming substrate and flavor substrate are heated to release an aerosol, and the flavor substrate is fluid permeable.

Fig. 3 shows a longitudinal section of an aerosol-generating article in which the tubular element comprises an inner airflow channel and an outer airflow channel.

Fig. 4 shows the aerosol-generating article of fig. 3 at a time when the aerosol-forming substrate and flavor substrate are heated to release the aerosol and the crossover element, flavor substrate, and permeability control element are fluid permeable.

Figure 5 shows a longitudinal section of an aerosol-generating article in which a flavour matrix is provided in the outer airflow channels of a tubular element.

Fig. 6 depicts the aerosol-generating article of fig. 5 at a time when the aerosol-forming substrate and flavor substrate are heated to release the aerosol and the crossover element, flavor substrate, and permeability control element are fluid permeable.

In fig. 7, a longitudinal section of an aerosol-generating article is shown, wherein the flavour matrix is the only permeability control element downstream of the air inlet in the outer airflow channel.

Fig. 8 depicts the aerosol-generating article of fig. 6 at a time when the aerosol-forming substrate and flavor substrate are heated to release the aerosol, and are fluid permeable across the element and flavor substrate.

Fig. 9 shows a longitudinal section of an aerosol-generating system comprising an aerosol-generating article and an aerosol-generating device.

Fig. 10 shows a housing of the aerosol-generating device of fig. 9 receiving an aerosol-generating article.

Fig. 11 shows a perspective view of the aerosol-generating device of fig. 9 and 10.

Fig. 12 shows a perspective view of a downstream induction heating device.

Fig. 13 is an exploded view of the downstream induction heating device of fig. 12.

Detailed Description

Fig. 1 depicts a longitudinal section of an aerosol-generating article 10 having an upstream end 13 and a downstream end 14, the aerosol-generating article 10 being defined in a longitudinal direction between the upstream end 13 and the downstream end 14. The article 10 includes an aerosol-forming substrate 11. In the embodiment of fig. 1, the tubular element 12 is arranged immediately downstream of the aerosol-forming substrate 11. The tubular member 12 defines an opening extending in a longitudinal direction and adapted for the flow of the matrix aerosol toward the downstream end 14. The tubular element 12 comprises an air inlet 15, whereby outside air can be sucked into the opening of the tubular element 12. The tubular member 12 defines at least one airflow passage to establish uninterrupted fluid communication between the upstream end 13 of the tubular member 12 and the downstream end 14 of the tubular member 12.

In the embodiment of fig. 1, the flavor substrate 16 is disposed immediately downstream of the tubular member 12 in the longitudinal direction. In this embodiment, the flavor substrate 16 comprises a gel composition. However, other flavors may be used in addition to or in place of the gel composition.

Providing the flavor substrate 16 downstream of the air inlet 15 included in the tubular member 12 allows for controlling the amount of airflow provided with the flavor substrate 16. The gel composition helps to produce a uniform matrix upon heating of the flavor matrix 16, which can produce a highly consistent flavor aerosol to entrain the matrix aerosol that can be generated by the aerosol-forming matrix 11 disposed upstream of the flavor matrix 16.

In the embodiment of fig. 1 to 8, the filter 17 is arranged immediately downstream of the tubular element 12 in the longitudinal direction, and the mouthpiece 22 is arranged immediately downstream of the filter 17.

The gel composition of the flavor matrix 16 in the embodiment of fig. 1 may be configured to be fluid permeable when the temperature of the gel composition is equal to or greater than the permeability transition temperature of the gel composition, as represented by the dots in fig. 2, and substantially fluid impermeable when the temperature of the gel composition is below the permeability transition temperature of the gel composition, as represented by the dashed lines in fig. 1. Thus, temperature changes in the flavor substrate can result in several characteristic changes in the aerosol-generating article 10. Heating the flavor substrate 16 to the transmittance transition temperature of the gel composition may cause an increase in the amount of airflow that may flow toward the downstream end 14 of the aerosol-generating article 10, as well as a decrease in the resistance to draw of the aerosol-generating article 10, as the airflow is able to travel through the permeable flavor substrate 16. The increase will depend on the percentage of the cross-sectional area occupied by the flavor substrate 16 relative to the maximum cross-sectional area of one or more airflow channels within the aerosol-generating article 10 at that cross-section. The flavor may be configured to be fluid permeable when the temperature of the flavor is equal to or greater than the permeability transition temperature of the flavor and to allow fluid flowing along the gas flow path to flow downstream of the flavor substrate 16 and configured to be substantially fluid impermeable when the temperature of the flavor is less than the permeability transition temperature of the flavor and to prevent fluid flowing along the gas flow path from flowing downstream of the flavor substrate 16, wherein the flavor is a gel composition.

In fig. 1-10, the permeability control element marked with a dashed line indicates that the permeability control element (such as a permeability control element, flavor matrix, or span element) is substantially fluid impermeable, while the permeability control element marked with a dot indicates that the permeability control element is fluid permeable.

The gel composition of the embodiment of fig. 1 may also be configured to be fluid impermeable at any operating temperature applied to the flavor substrate 16 by the aerosol-generating device. In this example, the flavor substrate 16 generally does not extend across the entire cross-section of the one or more airflow channels to allow airflow toward the downstream end 14. Alternatively, the flavor substrate 16 may block the airflow path. The flavor substrate 16 may extend across the entire cross-section of one or more of the airflow channels to block the airflow toward the downstream end 14. Thus, the flavor substrate 16 may extend across about 100% of the cross-section of the airflow channel. The flavor substrate 16 may extend across at least about 25% of the cross-section of the airflow channel. The flavor substrate 16 may extend across at least about 50% of the cross-section of the airflow channel. The flavor substrate 16 may extend across at least about 75% of the cross-section of the airflow channel.

The gel composition of the flavor substances of the flavor matrix 16 may have a composition comprising: from 50 to 75% by weight, preferably from 50 to 65% by weight, of glycerol present; 15 to 35 wt%, preferably 20 to 30 wt% Hydroxic Poly Metyl Cellulose (HPMC); 3 to 10 wt%, preferably 4 to 7 wt% agar; 0 to 12 wt%, preferably 0 to 7 wt% of fibres; 0 to 9 wt%, preferably 0 to 7 wt% of Low Methoxy (LM) (E440 i) pectin; 1.7 to 3.1 wt%, preferably 2.1 to 2.9 wt% lactic acid; 0 to 7 wt%, preferably 0 to 3 wt% Ca lactate; and nicotine, nicotine and a flavoring agent, or flavoring agent, in an amount of 0 to 4 wt%, preferably 0 to 2 wt%.

The flavoring agent may be one or more of menthol extract, vanilla extract, and coffee derivative flavoring agents. The coffee derivative flavoring agent comprises one or more of caffeine, guarana, taurine and glucuronolactone. When present in the gel composition, the flavoring agent is preferably present at 0.2 to 4 wt%, more preferably 0.4 to 2 wt%.

Examples of compositions of gel compositions that may be used in any of the permeability control elements, flavor matrices, or span elements described herein are shown in table 1 below. Table 1 shows the weight percent of each component of the gel composition:

the gel compositions listed above may provide predictable forms of the composition upon storage or shipment from the manufacturer to the consumer. The gel composition may substantially maintain its shape. The gel composition maintains its state at room temperature (about 21 degrees celsius). The gel composition is configured to be in a solid state over a temperature range that encompasses standard ambient temperatures for use of the aerosol-generating article. Suitable ambient temperatures may range from about minus 20 degrees celsius to about 70 degrees celsius. The overall state of the gel composition may be predominantly solid, or in the gel solid state, and fluid impermeable. Above about 70 degrees celsius, the overall state of the composition may be predominantly liquid and fluid permeable.

The gel compositions as set forth above may be configured to have sufficient resistance to deformation when in the solid state to provide mechanical stability to the flavor substrate for handling during manufacture, transportation, and use of the aerosol-generating article. The gel composition may have a deformation resistance of 0.5kgf to 3.0 kgf. The deformation resistance is preferably between 1.3kgf and 2.7kgf, more preferably between 1.9kgf and 2.5 kgf. The mechanical strength of the gel composition can be adjusted to a desired range by adjusting the amount of Low Methoxy (LM) pectin in the composition. The LM pectin used for this purpose will depend on the particular composition formulation, which may be used in a proportion of between 0.1 and 9 wt%, preferably between 0.1 and 7 wt%, and most preferably between 1 and 3 wt%.

The composition of the gel composition may be distributed in a variable manner within the flavor matrix. In alternative embodiments, the composition may have a homogeneous distribution. The flavor substrate may include an outer layer that is useful for imparting the flavor substrate with a desired shape to be disposed within the aerosol-generating article. The outer layer may be a shell. The remainder of the flavor matrix may be the core. Flavor matrices comprising a core and an outer layer are manufactured by first depositing a core comprising the remainder of the flavor matrix, and then depositing a layer on the core to form the outer layer. There are several types of manufacturing processes that are suitable. The core and outer layers may be manufactured by extrusion. A tubular core may be produced and the next step may be an extrusion process wherein the gel composition is uniformly deposited on the outer surface of the tubular core. The outer layer may be made of the same gel composition as the rest of the flavor matrix. The core and the outer layer may have the same characteristics. The core and the outer layer may have different characteristics. In one example, the core having lower mechanical strength is about 5% to about 20%, preferably about 10% to about 15%, softer than the hard outer layer (shell). Alternatively or additionally, if the gel composition includes a flavoring agent, the outer layer (shell) may not include a flavoring agent.

In the embodiment shown in fig. 1 and 2, the flavor substances of the flavor substrate 16 include flavor composition a or flavor composition B listed above in table 1.

Fig. 2 is a longitudinal section of the aerosol-generating article of fig. 1, depicting the moment in time wherein the flavor substrate 16 is at a temperature at which its gel composition is fluid permeable, as indicated by dots in the figure. Likewise, the aerosol-forming substrate 11 is heated to generate a substrate aerosol that entrains external air that enters the aerosol-generating article 10 at the upstream end 13 of the aerosol-generating article.

In fig. 2, outside air is drawn into the tubular member 12 through the air inlet 15. The flow of outside air and matrix aerosol reaches the flavor matrix 16. The flavor substrate 16 is fluid permeable and, in addition, is heated to form a flavor aerosol. The flavor aerosol is entrained with a flow of outside air and a matrix aerosol to form an aerosol that can be inhaled by a user. The entrained aerosol is filtered by the filter 17 and delivered to the user through the mouthpiece 22.

Fig. 3 shows a longitudinal section of an aerosol-generating article 10, wherein unlike the aerosol-generating article of fig. 1, the tubular element 12 comprises an outer airflow channel 18 and an inner airflow channel 19. In the embodiment of fig. 3, the flavor substrate 16 is disposed immediately downstream of the tubular member 12 in the longitudinal direction.

In the embodiment of fig. 3, a permeability control element 20 is disposed within the outer airflow channel 18. The permeability control element 20 is configured to be fluid permeable when the temperature of the permeability control element is equal to or greater than the permeability transition temperature of the permeability control element 20, such as when the temperature of the permeability control element 20 is 85 degrees celsius. Likewise, the permeability control element 20 is configured to be substantially fluid impermeable when the temperature of the permeability control element is below the permeability transition temperature of the permeability control element, such as when the temperature of the permeability control element is 20 degrees celsius. Thus, the permeability control element 20 may prevent fluid flow along the outer gas flow channel 18 downstream of the permeability control element 20 (as shown in FIG. 3) when its temperature is below its permeability transition temperature, and allow fluid flow along the outer gas flow channel 18 downstream of the permeability control element 20 (as shown in FIG. 4) when its temperature is equal to or greater than its permeability transition temperature. This may cause a change in several characteristics of the aerosol-generating article 10. Heating the permeability control element 20 to its permeability transition temperature may cause an increase in the amount of airflow that may flow toward the downstream end 14 of the aerosol-generating article 10, as well as a decrease in the suction resistance of the aerosol-generating article 10, as airflow is able to flow along the outer airflow channel 18. Likewise, the permeability control element 20 may be advantageously used to regulate the amount of airflow provided with the flavor substrate 16.

In the embodiment of fig. 3, a spanning member 21 is provided in the outer airflow channel 18 to block or regulate the flow of the matrix aerosol into the outer airflow channel 18. The spanning member 21 may be a permeability control member. When the spanning member 21 is a permeability control member, if the temperature of the spanning member 21 is equal to or greater than the permeability transition temperature of the spanning member 21, for example at 85 degrees celsius, then the matrix aerosol may flow into the outer airflow channel 18 upon heating of the aerosol-forming substrate 11. Also, if the temperature of the spanning member 21 is below the transmission transition temperature of the spanning member 21, e.g., at 20 degrees celsius, the substrate aerosol may be prevented from flowing into the outer airflow channel 18 upon heating of the aerosol-forming substrate 11.

In this embodiment, the permeability control element 20 and the spanning element 21 comprise a gel composition. However, in alternative embodiments, the permeability control element 20 and the spanning element 21 comprise other suitable materials to achieve the desired change in permeability as a function of material temperature.

In the embodiment shown in fig. 3 and 4, the permeability control element 20 and the span element 21 comprise either the no-flavor composition a or the no-flavor composition B listed above in table 1.

In the embodiment of fig. 3, the filter 17 is arranged immediately downstream of the tubular element 12 in the longitudinal direction, and the mouthpiece 22 is arranged immediately downstream of the filter 17.

The gel composition of the flavor matrix 16 in the embodiment of fig. 3 may also be configured to be fluid permeable when the temperature of the gel composition is equal to or greater than the permeability transition temperature of the gel composition, as indicated by the dots in fig. 3, and substantially fluid impermeable when the temperature of the gel composition is below the permeability transition temperature of the gel composition, as indicated by the dashed lines in fig. 4. Thus, the flavor substrate 16 may also be a permeability control element. In other embodiments, the gel composition of the embodiment of fig. 3 may be configured to be substantially fluid impermeable at any operating temperature applied to the flavor substrate by the aerosol-generating device. In the latter embodiment, the flavour matrix typically does not extend across the entire cross-section of the one or more airflow channels in order to allow airflow towards the downstream end of the aerosol-generating article.

In the embodiment shown in fig. 3 and 4, the flavor substances of the flavor substrate 16 include flavor composition a or flavor composition B listed above in table 1.

Fig. 4 is a longitudinal section of the aerosol-generating article of fig. 1, depicting the moment in time when the permeability control element 20, the spanning element 21 and the flavor substrate 16 are each at a temperature at which they are fluid permeable, as indicated by dots in the figure. Likewise, the aerosol-forming substrate 11 is heated to generate a substrate aerosol that entrains external air that enters the aerosol-generating article 10 at the upstream end 13 of the aerosol-generating article. A substantial percentage of the matrix aerosol flows along the inner airflow passage 19 of the tubular member 12. Since the spanning member 21 in fig. 4 is fluid permeable, a percentage of the matrix aerosol flows along the outer airflow channel 18. In examples where the spanning element is permanently fluid impermeable at any operating temperature of the aerosol-generating article, all of the aerosol of the substrate generated upon heating of the aerosol-forming substrate flows along the inner airflow channel.

In fig. 4, outside air is sucked into the outside air flow passage 18 through the air inlet 15. The flow of outside air and matrix aerosol reaches the flavor matrix 16 because the permeability control element 20 is fluid permeable at the moment shown in fig. 4. The flavor substrate 16 is also fluid permeable and, in addition, is heated to form a flavor aerosol. The flavor aerosol is entrained with a flow of outside air and a matrix aerosol to form an aerosol that can be inhaled by a user. The entrained aerosol is filtered by the filter 17 and delivered to the user through the mouthpiece 22.

Fig. 5 shows a longitudinal section of an aerosol-generating article 10 in which unlike the aerosol-generating article of fig. 3, a flavour matrix 16 comprising a gel composition is arranged within an outer airflow channel 18 between an air inlet 15 and a permeability control element 20.

In this embodiment, the flavor substrate 16 is a permeability control element. Thus, as shown in fig. 5, the flavor substrate 16 prevents airflow downstream of the flavor substrate 16 along the outer airflow channel 18 when its temperature is below the permeability transition temperature of the gel composition. Also, as also shown in FIG. 5, the permeability control element 20 prevents airflow downstream of the permeability control element 20 along the outer airflow passage 18 when its temperature is below the permeability transition temperature of the permeability control element 20. As shown in fig. 6, the flavor substrate 16 allows airflow downstream of the flavor substrate 16 along the outer airflow channel 18 when its temperature is equal to or greater than the permeability transition temperature of the gel composition. As also depicted in fig. 6, the permeability control element 20 allows airflow downstream of the permeability control element 20 along the outer airflow channel 18 when its temperature is equal to or greater than the permeability transition temperature of the permeability control element 20.

A spanning member 21 is disposed within the outer airflow passage 18 upstream of the air inlet 15. The spanning member 21 may be a permeability control member. When the spanning member 21 is a permeability control member, the matrix aerosol may flow into the outer airflow channel 18 upon heating of the aerosol-forming substrate 11 when the temperature of the spanning member 21 is equal to or greater than the permeability transition temperature of the spanning member 21.

Fig. 6 is a longitudinal section of the aerosol-generating article of fig. 5, depicting the moment in time when the permeability control element 20, the spanning element 21 and the flavor substrate 16 are each at a temperature at which they are fluid permeable, as indicated by dots in the figure. Likewise, the aerosol-forming substrate 11 is heated to generate a substrate aerosol that entrains external air that enters the aerosol-generating article 10 at the upstream end 13 of the aerosol-generating article. A substantial percentage of the matrix aerosol flows along the inner airflow passage 19 of the tubular member 12. Since the spanning member 21 in fig. 6 is fluid permeable, a percentage of the matrix aerosol flows along the outer airflow channel 18. In examples where the spanning element is permanently fluid impermeable, all of the aerosol-forming substrate 11 generated upon heating of the aerosol-forming substrate flows along the inner airflow channel.

In fig. 6, outside air is sucked into the outside air flow passage 18 through the air inlet 15. The flavor substrate 16 is also fluid permeable and, in addition, heated to form a flavor aerosol within the outer gas flow channel 18. The flavor aerosol entrains a flow of outside air and a percentage of the matrix aerosol in the outer airflow channel 18. The aerosol thus produced reaches the filter 17, since the permeability control element 20 arranged downstream of the flavour base 16 is fluid permeable at the moment indicated in figure 6. The aerosol is then entrained with a percentage of the matrix aerosol flowing along the inner airflow passage 19 to form an aerosol that can be inhaled by the user. The aerosol is delivered to the user through the mouthpiece 22.

In the embodiment shown in fig. 5 and 6, the permeability control element 20 and the span element 21 each comprise either the no-flavor composition a or the no-flavor composition B listed above in table 1.

In the embodiment shown in fig. 5 and 6, the flavor substances of the flavor substrate 16 include flavor composition a or flavor composition B listed above in table 1.

Fig. 7 shows a longitudinal section of an aerosol-generating article 10, wherein unlike the aerosol-generating article of fig. 5, the flavour matrix 16 comprising a gel composition is the only permeability control element arranged downstream of the air inlet 15 within the outer airflow channel 18. Thus, as shown in fig. 7, the flavor substrate 16 prevents air flow downstream of the tubular member 12 along the outer air flow channel 18 when its temperature is below the permeability transition temperature of the gel composition. Also, as shown in fig. 8, the flavor substrate 16 allows airflow downstream of the tubular member 12 along the outer airflow path 18 when its temperature is equal to or greater than the permeability transition temperature of the gel composition.

Fig. 8 is a longitudinal section of the aerosol-generating article of fig. 7, depicting the moment in time when the spanning member 21 and the flavor substrate 16 are each at a temperature at which they are fluid permeable, as indicated by dots in the figure. Likewise, the aerosol-forming substrate 11 is heated to generate a substrate aerosol that entrains external air that enters the aerosol-generating article 10 at the upstream end 13 of the aerosol-generating article. A substantial percentage of the matrix aerosol flows along the inner airflow passage 19 of the tubular member 12. Since the spanning member 21 in fig. 8 is fluid permeable, a percentage of the matrix aerosol also flows along the outer airflow channel 18. In examples where the spanning element is permanently fluid impermeable, all of the aerosol of the substrate generated upon heating of the aerosol-forming substrate flows along the inner airflow channel.

In fig. 8, outside air is sucked into the outside air flow passage 18 through the air inlet 15. The flavor substrate 16 is fluid permeable at the moment of fig. 8 and, in addition, is heated to form a flavor aerosol within the outer gas flow channel 18. Thus, the flavor aerosol entrains a flow of outside air and a percentage of matrix aerosol in the outer airflow channel 18. The aerosol thus produced is entrained with a percentage of the matrix aerosol flowing along the inner airflow passage 19 to form an aerosol that can be inhaled by the user. The aerosol is filtered by the filter 17 and delivered to the user through the mouthpiece 22.

In the embodiment shown in fig. 7 and 8, the spanning element 21 comprises the odorless composition a or odorless composition B listed above in table 1.

In the embodiment shown in fig. 7 and 8, the flavor substances of the flavor substrate 16 include flavor composition a or flavor composition B listed above in table 1.

Fig. 9 shows a schematic cross-sectional view of an aerosol-generating system comprising an aerosol-generating device 200 and an aerosol-generating article 10. The aerosol-generating article 10 may be any of the articles of fig. 1 to 8.

The aerosol-generating device 200 comprises a substantially cylindrical device housing 207 having a shape and size similar to a conventional cigar.

The aerosol-generating device 200 further comprises a power supply 201 in the form of a rechargeable nickel cadmium battery, a controller 202 in the form of a printed circuit board comprising a microprocessor, an electrical connector 203 and a heater 204. The heater 204 comprises a substrate heating element 205 configured to heat the aerosol-forming substrate 11, and a downstream heating element 206 disposed downstream of the substrate heating element 205. The downstream heating element 206 is configured to heat the flavor substrate 16, and in a corresponding embodiment, the permeability control element 20 and the span element 21.

In the embodiment of fig. 9, the substrate heating element 205 and the downstream heating element 206 are a substrate induction heating device 205 and a downstream induction heating device 206, respectively, each comprising at least one inductor coil and at least one susceptor. However, other forms of heating elements may be used, such as resistive heating elements.

The power supply 201, the controller 202, and the induction heating devices 205, 206 are all housed within a device housing 207. The induction heating means 205, 206 of the aerosol-generating device 200 are arranged at the proximal end of the device 200. The electrical connector 203 is disposed at the distal end of the device housing 207.

As used herein, the term "proximal" refers to the user end or mouth end of an aerosol-generating device or aerosol-generating article. The proximal end of the aerosol-generating device or component of the aerosol-generating article is the end of the component closest to the user end or mouth end of the aerosol-generating device or aerosol-generating article. As used herein, the term "distal" refers to the end opposite the proximal end.

The controller 202 is configured to control the supply of electrical power from the power source 201 to the induction heating means 205, 206. The controller 202 further includes a DC/AC inverter including a class D power amplifier. The controller 202 is also configured to control recharging of the power supply 201 from the electrical connector 203. The controller 202 further includes a puff sensor (not shown) configured to sense when a user puffs on the aerosol-generating article received in the device cavity 208.

The substrate induction heating device 205 comprises a substrate inductor coil 209 and a substrate susceptor 210. The substrate susceptor 210 is a sheet-type susceptor configured to penetrate into the aerosol-forming substrate 11 to provide internal heating to the aerosol-forming substrate 11. In the embodiment of fig. 9, the substrate inductor coil 209 is tubular and is concentrically disposed about a portion of the cavity 208 configured to receive the aerosol-forming substrate 11.

The matrix inductor coil 209 is connected to the controller 202 and the power supply 201, and the controller 202 is configured to supply varying current to the matrix inductor coil 209. When a varying current is supplied to the substrate inductor coil 209, the substrate inductor coil 209 generates a varying magnetic field which heats the substrate susceptor 210 by induction.

The downstream induction heating device 206 comprises a downstream inductor coil 211 and a downstream susceptor 212. The downstream susceptor 212 is a tubular susceptor configured to be disposed concentrically around a section of the aerosol-generating article 10 comprising the flavor substrate 16 so as to provide external heating to the flavor substrate 16. When the aerosol-generating article 10 comprises the permeability control element 20, the spanning element 21, or both, the downstream susceptor 212 is further configured to be disposed concentrically around the section of the aerosol-generating article 10 comprising the permeability control element 20 and the spanning element 21. In the embodiment of fig. 9, the downstream inductor coil 211 is tubular and is disposed concentrically with the downstream susceptor 212.

The downstream inductor coil 211 is connected to the controller 202 and the power supply 201, and the controller 202 is configured to supply varying current to the downstream inductor coil 211. When a varying current is supplied to the downstream inductor coil 211, the downstream inductor coil 211 generates a varying magnetic field that heats the downstream susceptor 212 by induction.

As shown in fig. 10, the device housing 207 also defines a matrix device air inlet 213 proximate to the distal end of the cavity 208 for receiving the aerosol-generating article 10. The matrix device air inlet 213 is configured to enable ambient air to be drawn into the device housing 207 towards the aerosol-forming substrate 11. The device housing 207 also defines a downstream device air inlet 214. The downstream device air inlet 214 is configured such that ambient air can be drawn into the device housing 202 towards the air inlet 15 of the tubular element 12 of the aerosol-generating article 10. For this reason, the downstream device air inlet 214 is configured to substantially match the air inlet 15 of the tubular element 12 when the aerosol-generating article 10 is fully introduced into the device cavity 208.

Fig. 11 shows an external view of the aerosol-generating device 200 of fig. 9 and 10. The external surfaces of the substrate induction heating apparatus 205 and the downstream induction heating apparatus 206 are shown in fig. 11. Upstream of the substrate induction heating device 205, the aerosol-generating device 200 comprises a button 212 configured to turn on and off components of the heater 204.

The downstream induction heating device 206 is also shown in fig. 12 as being separate from the rest of the aerosol-generating device 200 to illustrate that in this embodiment, the downstream induction heating device 206 may be removably attached to the rest of the aerosol-generating device 200.

Fig. 13 is an exploded view of the downstream induction heating device 206 of fig. 12, depicting the downstream inductor coil 211 and the downstream susceptor 212.

Claims

1. An aerosol-generating article having an upstream end and a downstream end, the aerosol-generating article defining a longitudinal direction between the upstream end and the downstream end, the aerosol-generating article comprising:

an aerosol-forming substrate;

a flavor substrate disposed downstream of the air inlet, the flavor substrate comprising a flavor configured to be fluid permeable when a temperature of the flavor is equal to or greater than a permeability transition temperature of the flavor and configured to be substantially fluid impermeable when the temperature of the flavor is less than the permeability transition temperature of the flavor, wherein the flavor is a gel composition.

2. An aerosol-generating article according to claim 1, wherein the tubular element defines at least one airflow channel such that uninterrupted fluid communication is established between an upstream end of the tubular element and a downstream end of the tubular element, wherein the flavour base is configured to allow fluid flowing along the airflow channel to flow downstream of the flavour base when the temperature of the flavour substance is equal to or greater than the permeability transition temperature of the flavour substance, and to prevent fluid flowing along the airflow channel from flowing downstream of the flavour base when the temperature of the flavour substance is below the permeability transition temperature of the flavour substance.

3. An aerosol-generating article according to claim 1 or claim 2, wherein the flavour substance is thermoreversible.

4. An aerosol-generating article according to any one of the preceding claims, wherein the flavour substance has a permeance transition temperature of between 70 degrees celsius and 80 degrees celsius.

5. An aerosol-generating article according to any one of the preceding claims, wherein the suction resistance of the aerosol-generating article at a temperature of the flavour mass equal to or greater than the permeability transition temperature of the flavour mass is at least 10mm H greater than the suction resistance of the aerosol-generating article at a temperature of the flavour mass below the permeability transition temperature of the flavour mass ₂ O, preferably 20mm H ₂ O, even more preferably 30mm H ₂ O。

6. An aerosol-generating article according to any preceding claim, wherein a distance between an upstream end of the aerosol-forming substrate and a downstream end of the flavour substrate is less than about 40 mm.

7. An aerosol-generating article according to any one of the preceding claims, further comprising an adjustment member disposed on and movable relative to the tubular element such that the adjustment member is configured to change the size of the air inlet.

8. An aerosol-generating article according to any one of the preceding claims, wherein the tubular element comprises an inner tube and an outer tube, the outer tube being arranged around the inner tube, wherein an outer gas flow channel is longitudinally delimited by the inner tube and the outer tube, wherein an inner gas flow channel is longitudinally delimited by the inner tube, and wherein at least the inner gas flow channel is adapted for a matrix aerosol to flow towards the downstream end.

9. An aerosol-generating article according to claim 8, wherein the flavour matrix is disposed within the outer airflow channel.

10. An aerosol-generating article according to claim 8 or claim 9, further comprising at least one permeability control element,

Wherein the at least one permeability control element is configured to be fluid permeable when the temperature of the at least one permeability control element is equal to or greater than the permeability transition temperature of the at least one permeability control element,

11. An aerosol-generating article according to claim 9 and claim 10, wherein the flavour matrix is a permeability control element.

12. An aerosol-generating article according to claim 10 or claim 11, further comprising a spanning element disposed within the outer airflow channel, wherein the outer airflow channel comprises the air inlet, and the air inlet is disposed downstream of the spanning element.

13. An aerosol-generating article according to any one of the preceding claims, further comprising a filter arranged downstream of the tubular element.

14. An aerosol-generating system, the aerosol-generating system comprising:

an aerosol-generating article according to any one of the preceding claims, and

an aerosol-generating device comprising a heater comprising a substrate heating element configured to heat the aerosol-generating article and a downstream heating element disposed downstream of the substrate heating element.

15. An aerosol-generating system according to claim 15, wherein the substrate heating element is a substrate induction heating device comprising a substrate inductor coil and a substrate susceptor, and wherein the downstream heating element is a downstream induction heating device comprising a downstream inductor coil and a downstream susceptor.