CN115666280A

CN115666280A - Aerosol-generating system with air entry region

Info

Publication number: CN115666280A
Application number: CN202180020322.0A
Authority: CN
Inventors: G·B·鲍尔; D·桑纳; J·于蒂里
Original assignee: Philip Morris Products SA
Current assignee: Philip Morris Products SA
Priority date: 2020-03-12
Filing date: 2021-03-12
Publication date: 2023-01-31
Also published as: JP2023516468A; EP4117466C0; KR20220154137A; WO2021180967A1; BR112022017245A2; US20230115277A1; EP4117466B1; EP4117466A1

Abstract

An aerosol-generating system (100) is provided comprising an aerosol-generating article (1) and an aerosol-generating device (10). An aerosol-generating article comprises a rod (12) of aerosol-forming substrate and a filter positioned downstream of the rod of aerosol-forming substrate. A rod of aerosol-forming substrate and a filter are assembled within a wrapper (22). The aerosol-generating article comprises a first air entry region (15) on the wrapper. The first air entry zone is configured to allow air to enter the interior of the aerosol-generating article. The aerosol-generating device has a distal end and a mouth end (2). The aerosol-generating device comprises a housing (4). The housing defines a device cavity for removably receiving an aerosol-generating article at a mouth end of the device. The aerosol-generating device comprises a heater for heating the aerosol-forming substrate when the aerosol-generating article is received within the device cavity. The aerosol-generating device comprises an airflow channel (5) extending between a channel inlet (7) and a channel outlet (9). The airflow channel is configured to establish fluid communication between an interior of the device cavity and an exterior of the aerosol-generating device. The aerosol-generating system is configured such that, when the aerosol-generating article is received within the device cavity, fluid communication between an interior of the aerosol-generating article and an exterior of the aerosol-generating device is established by fluid communication established between a first air entry region of the aerosol-generating article received within the device cavity and an air flow channel of the aerosol-generating device.

Description

Aerosol-generating system with air entry region

Technical Field

The present invention relates to an aerosol-generating system comprising an aerosol-generating device configured to receive an aerosol-generating article.

Background

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

A number of prior art documents disclose aerosol-generating devices for consuming aerosol-generating articles. Such devices include, for example, electrically heated aerosol-generating devices in which an aerosol is generated by transferring heat from one or more electric heater elements of the aerosol-generating device to an aerosol-forming substrate of a heated aerosol-generating article.

In general, aerosol-generating articles are particularly suitable for use in conjunction with a particular aerosol-generating device, or aerosol-generating devices are particularly suitable for use in conjunction with a particular aerosol-generating article. In particular, it may be required that certain aerosol-generating articles are not used with a particular aerosol-generating device. This may be because certain articles are suitable for being heated by the heating element of a particular aerosol-generating device, as such devices may overheat certain aerosol-generating articles or not heat other aerosol-generating articles.

It is therefore desirable to provide an aerosol-generating system in which incompatible aerosol-generating articles are prevented from being used with, or incompatible aerosol-generating devices are prevented from being used with, particular aerosol-generating articles.

Disclosure of Invention

In the present description, an aerosol-generating system is provided comprising an aerosol-generating article and an aerosol-generating device. An aerosol-generating article comprises a rod of aerosol-forming substrate and a filter positioned downstream of the rod of aerosol-forming substrate. A rod of aerosol-forming substrate and a filter are assembled within the wrapper. The aerosol-generating article comprises a first air entry region located on the wrapper. The first air entry zone is configured to allow air to enter the interior of the aerosol-generating article. The aerosol-generating device has a distal end and a mouth end. The aerosol-generating device comprises a housing. The housing defines a device cavity for removably receiving an aerosol-generating article at a mouth end of the device. The aerosol-generating device comprises a heater for heating the aerosol-forming substrate when the aerosol-generating article is received within the device cavity. The aerosol-generating device comprises an airflow channel extending between a channel inlet and a channel outlet. The airflow channel is configured to establish fluid communication between an interior of the device cavity and an exterior of the aerosol-generating device. The aerosol-generating system is configured such that, when the aerosol-generating article is received within the device cavity, fluid communication between an interior of the aerosol-generating article and an exterior of the aerosol-generating device is established by fluid communication established between a first air entry region of the aerosol-generating article received within the device cavity and an air flow channel of the aerosol-generating device.

In the present description, an aerosol-generating system is provided comprising an aerosol-generating article and an aerosol-generating device. An aerosol-generating article may comprise a rod of aerosol-forming substrate. The aerosol-generating article may comprise a filter positioned downstream of the rod of aerosol-forming substrate. The rod of aerosol-forming substrate may be assembled within a wrapper. The filter may be assembled in a wrapper. The aerosol-generating article may comprise a first air entry region located on the wrapper. The first air entry zone may be configured to allow air to enter the interior of the aerosol-generating article. The aerosol-generating device may have a distal end and a mouth end. The aerosol-generating device may comprise a housing. The housing may define a device cavity for removably receiving the aerosol-generating article at the mouth end of the device. The aerosol-generating device may comprise a heater for heating the aerosol-forming substrate when the aerosol-generating article is received within the device cavity. The aerosol-generating device may comprise an airflow channel extending between a channel inlet and a channel outlet. The airflow channel may be configured to establish fluid communication between the interior of the device cavity and the exterior of the aerosol-generating device. The aerosol-generating system may be configured such that, when the aerosol-generating article is received within the device cavity, fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device may be established by fluid communication established between the first air entry region of the aerosol-generating article received within the device cavity and the air flow channel of the aerosol-generating device.

In this specification, a downstream section may refer to one or more components located downstream of a rod of aerosol-forming substrate. The filter may be a downstream segment. The filter may form part of the downstream section. The downstream section may comprise a filter.

In the present description, an aerosol-generating system is provided comprising an aerosol-generating article and an aerosol-generating device. An aerosol-generating article may comprise a rod of aerosol-forming substrate. The aerosol-generating article may comprise a downstream section positioned downstream of the stem of the aerosol-forming substrate. The rod of aerosol-forming substrate may be assembled within a wrapper. The downstream section may be assembled within the packaging material. The aerosol-generating article may comprise a first air entry region located on the wrapper. The first air entry region may be configured to allow air to enter the interior of the aerosol-generating article. The aerosol-generating device may have a distal end and a mouth end. The aerosol-generating device may comprise a housing. The housing may define a device cavity for removably receiving the aerosol-generating article at the mouth end of the device. The aerosol-generating device may comprise a heater for heating the aerosol-forming substrate when the aerosol-generating article is received within the device cavity. The aerosol-generating device may comprise an airflow channel extending between a channel inlet and a channel outlet. The airflow channel may be configured to establish fluid communication between the interior of the device cavity and the exterior of the aerosol-generating device. The aerosol-generating system may be configured such that, when the aerosol-generating article is received within the device cavity, fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device may be established by fluid communication established between the first air entry region of the aerosol-generating article received within the device cavity and the air flow channel of the aerosol-generating device.

The aerosol-generating article may comprise an aerosol former. The aerosol-forming substrate may have an aerosol former content of greater than about 10% by dry weight.

The filter or downstream section may comprise a hollow tubular section. The hollow tubular section may be located downstream of the rod of aerosol-forming substrate. The hollow tubular section may be located immediately downstream of the rod of aerosol-forming substrate.

In order to consume an aerosol-generating article and generate an aerosol within the aerosol-generating device of the present invention, fluid communication must be established between the interior of the aerosol-generating article and the exterior of the aerosol-generating device. During consumption, a user may draw on the aerosol-generating article such that the user may experience and consume the aerosol generated within the aerosol-generating article. By such a pumping action, air may flow from outside the aerosol-generating device, through the aerosol-generating device, into and through the aerosol-generating article, in order to deliver an aerosol generated within the article into the mouth of a user.

By configuring the aerosol-generating system such that fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device is established by fluid communication established between the first air entry region of the aerosol-generating article received within the device cavity and the air-flow channel of the aerosol-generating device, compatible aerosol-generating articles are ensured for use with the aerosol-generating device. For use in the aerosol-generating system of the present invention, a compatible aerosol-generating article needs to have a first air entry region configured in such a way that, when the aerosol-generating article is received within the device cavity, fluid communication is established between the first air entry region of the aerosol-generating article and the air flow passage of the aerosol-generating device. Furthermore, compatible aerosol-generating devices need to have an air flow channel configured in such a way that it establishes fluid communication with the first air entry region of the aerosol-generating article received within the device.

The fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device may be established by an airflow channel outlet of the aerosol-generating device which overlies or overlaps a first air entry region of the aerosol-generating article received within the device cavity. Accordingly, compatible aerosol-generating articles need to have a first air entry region configured in such a way that, when the aerosol-generating device is received within the device cavity, the air flow channel outlet of the aerosol-generating device covers or overlaps the first air entry region of the aerosol-generating article. Furthermore, compatible aerosol-generating devices need to have an air flow channel configured in such a way that the outlet covers or overlaps the first air entry region of the aerosol-generating article when the aerosol-generating article is received within the device.

If incompatible aerosol-generating articles are used with the aerosol-generating devices of the presently disclosed aerosol-generating systems, the user may not be able to use the aerosol-generating system and may not consume, or at least not experience, the incompatible aerosol-generating articles at all. Furthermore, if compatible aerosol-generating articles are used with different aerosol-generating devices not belonging to the aerosol-generating system of the present disclosure, the user may also not be able to use the aerosol-generating system and may not consume, or at least not experience, the compatible aerosol-generating articles at all. This is because if the airflow passage outlet of the aerosol-generating device is not aligned with the first air entry region of the aerosol-generating device, fluid communication between the interior of the aerosol-generating device and the exterior of the aerosol-generating device may not be properly or fully established.

Fluid communication between the exterior of the aerosol-generating device and the interior of the aerosol-generating article may be established by partial or complete overlap or alignment between the outlet of the airflow channel of the device and the first air entry region of the article.

The fluid communication between the exterior of the aerosol-generating device and the interior of the aerosol-generating article may be established by partial or complete overlap or alignment between the airflow channels of the device and the first air entry region of the article.

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

As used herein, the term "longitudinal" refers to a direction corresponding to the major longitudinal axis of an aerosol-generating article or device, which extends between an upstream end and a downstream end of the aerosol-generating article or aerosol-generating device.

As used herein, the terms "upstream" and "downstream" describe the relative position of an aerosol-generating article or a component or part of a component of a device with respect to the direction in which an aerosol is conveyed through the aerosol-generating article during use.

The term "mouth end" refers to the portion of an element or component that is configured to be positioned in or near the mouth of a user during normal use of the element or component. The mouth end of a component may also correspond to the downstream end of the same component. For example, the mouth end of the aerosol-generating article may also be the downstream end of the article. The mouth end of the aerosol-generating article or device is configured to be placed in or near the mouth of a consumer during normal use. The mouth end of the aerosol-generating device may also be referred to as the proximal end of the aerosol-generating device.

During use, air is drawn through the aerosol-generating article, primarily in the longitudinal direction. Outside the device, air may be drawn through the article via the upstream end.

The term "transverse" refers to a direction perpendicular to the longitudinal axis. Any reference to a "cross-section" of an aerosol-generating article or a component of an aerosol-generating article refers to a transverse cross-section, unless otherwise specified.

The term "length" denotes the dimension of a component of an aerosol-generating article or device relative to the longitudinal direction.

The device cavity may be referred to as a heating chamber of the aerosol-generating device. The device lumen may extend between the distal end and the mouth end or proximal end. The distal end of the device lumen may be a closed end, while the mouth or proximal end of the device lumen may be an open end. The aerosol-generating article may be inserted into the device cavity or the heating chamber via the open end of the device cavity. The device cavity may be cylindrical so as to conform to the same shape of the aerosol-generating article.

The expression "received within" may refer to the fact that a component or element is received completely or partially within another component or element. For example, the expression "the aerosol-generating article is received within the device cavity" means that the aerosol-generating article is received fully or partially within the device cavity of the aerosol-generating article. The aerosol-generating article may abut the distal end of the device cavity when the aerosol-generating article is received within the device cavity. When the aerosol-generating article is received within the device cavity, the aerosol-generating article may be substantially proximal to the distal end of the device cavity. The distal end of the device lumen may be defined by an end wall.

The length of the device lumen may be between about 10mm and about 50 mm. The length of the device lumen may be between about 20mm and about 40 mm. The length of the device lumen may be between about 25mm and about 30 mm. The length of the device cavity may be equal to or greater than the length of the rod of aerosol-forming substrate.

The diameter of the device lumen may be between about 4mm and about 50 mm. The diameter of the device lumen may be between about 4mm and about 30 mm. The device lumen may be between about 5mm and about 15mm in diameter. The device lumen may be between about 6mm and about 12mm in diameter. The diameter of the device lumen may be between about 7mm and about 10 mm. The device lumen may be between about 7mm and about 8mm in diameter.

The diameter of the device cavity may be equal to or greater than the diameter of the aerosol-generating article. The diameter of the device cavity may be the same as the diameter of the aerosol-generating article so as to establish a close fit with the aerosol-generating article.

The device cavity may be configured to establish a tight fit with an aerosol-generating article received within the device cavity. A tight fit may refer to a snug fit. The aerosol-generating device may comprise a peripheral wall. The material perimeter wall may define a device cavity or a heating chamber. The peripheral wall defining the device cavity may be configured to engage with the aerosol-generating article received within the device cavity in a close-fitting manner such that there is substantially no gap or empty space between the peripheral wall defining the device cavity and the aerosol-generating article when the aerosol-generating article is received within the device.

Such a close fit may establish an air-tight fit or configuration between the device cavity and the aerosol-generating article received therein. Such an airtight configuration may mean that air can only be drawn into the interior of the aerosol-generating article through the alignment or overlap of the airflow channel outlet and the first air entry zone. With such an air-tight configuration, there will be substantially no gaps or empty spaces for air to flow through between the peripheral wall defining the device cavity and the aerosol-generating article. Thus, when incompatible aerosol-generating articles are used with aerosol-generating devices, such alignment may not occur, and thus air may not be drawn through the incompatible aerosol-generating articles.

The close fit with the aerosol-generating article may be established along the entire length of the device cavity or along a portion of the length of the device cavity. A tight fit may be established at a location downstream of the first air entry region of the aerosol-generating article. The portion of the peripheral wall configured to establish such a tight fit may be referred to as a sealing portion of the peripheral wall. Such a tight fit may be established when the airflow passage is defined within the thickness of the peripheral wall of the aerosol-generating device. The sealing portion of the perimeter wall may be defined along the entire length of the device cavity.

When the airflow passage is defined on an inner surface of the peripheral wall of the device housing, a portion of the peripheral wall between the airflow passage and the distal end of the device cavity may define a sealed portion of the peripheral wall. This will ensure that air does not flow beyond the airflow channel towards the upstream end of the aerosol-generating article. When received within the device, the portion of the peripheral wall between the airflow channel and the distal end of the device cavity may form an air-tight configuration with the upstream portion of the aerosol-generating article.

The sealing portion of the peripheral wall may be configured to establish an air-tight fit with a portion of the aerosol-generating article at a location downstream of the first air entry region of the aerosol-generating article. The sealing portion of the peripheral wall may be configured to establish an airtight fit with a portion of the aerosol-generating article at a location downstream of the second air entry region of the aerosol-generating article.

The diameter of the device cavity may vary along the longitudinal direction of the aerosol-generating device. The diameter of the device lumen may decrease from the distal end of the device lumen to the sealing portion of the peripheral wall.

The diameter of the device lumen may increase from the sealing portion of the peripheral wall in a direction toward the distal end of the device lumen. The diameter of the device lumen between the distal end of the device lumen and the sealing portion of the peripheral wall may be greater than the diameter of the remainder of the device lumen. The diameter of the device cavity may increase in a direction away from the sealing portion of the peripheral wall and away from the mouth end of the device.

By having a portion of the device cavity with one or more larger diameters than the remainder of the device cavity, the device cavity may define a gap or chamber around (surrounding) the upstream portion of the aerosol-generating article when the aerosol-generating article is received within the device. In such embodiments, the alignment or overlap between the first air entry zone and the first outlet of the airflow channel of the device may not be necessary to ensure fluid communication between the exterior of the device and the interior of the article. The airflow still needs to enter the article via the first air entry zone. Air flowing into the device cavity via the first outlet of the air flow channel may flow into such a gap or chamber and then be drawn into the article via the first air entry zone. Such a gap or chamber may provide a cushion of air around said upstream portion of the article, which cushion of air may be heated by the heater of the device, or act as a cushion of cooling air around the article.

The aerosol-generating device may comprise a peripheral wall defining a device cavity, and the aerosol-generating device may comprise a circumferential protrusion extending from the peripheral wall into the device cavity, the circumferential protrusion being configured to establish an air-tight fit with a portion of the aerosol-generating article at a location downstream of the first air entry region of the aerosol-generating article when received within the aerosol-generating device.

The diameter of the device cavity may be greater than the diameter of the aerosol-generating article and the inner diameter of the circumferential projection may be the same as the diameter of the aerosol-generating article, such that a tight fit is established between the article and the circumferential projection once the article is received within the aerosol-generating device. The inner diameter of the circumferential projection may even be smaller than the diameter of the aerosol-generating article. This ensures that the air-tight fit is established more reliably.

By establishing an air-tight fit with the aerosol-generating article downstream of the first air entry region, it is further ensured that air can only enter the interior of the aerosol-generating article through the alignment of the air flow passage outlet and the first air entry region. This may be achieved by a sealing portion of the peripheral wall or a circumferential projection, both of which are described above.

When the aerosol-generating article is received within the device cavity, the upstream end of the aerosol-generating article may be blocked, thereby substantially preventing air from entering the aerosol-generating article through the upstream end of the aerosol-generating article. However, when the aerosol-generating article is not received within the aerosol-generating device, air may flow through the aerosol-generating article through the upstream end of the aerosol-generating article. When the article is received or inserted into the device, the upstream end of the aerosol-generating article may surround the distal end of the device cavity such that air can no longer flow past the upstream end of the article. Thus, air flowing through the airflow channel may only be able to be drawn through the article via the first air entry region. The upstream end of the aerosol-generating article may be defined by an upstream end of a rod of aerosol-forming substrate.

The aerosol-generating device may comprise an airflow channel extending between a channel inlet and a channel outlet. The airflow channel may be configured to establish fluid communication between the interior of the device cavity and the exterior of the aerosol-generating device. The air flow passage of the aerosol-generating device may be defined within a housing of the aerosol-generating device to enable fluid communication between an interior of the device cavity and an exterior of the aerosol-generating device. The air flow passage may be configured to provide an air flow into the article when the aerosol-generating article is received within the device cavity, in order to deliver the generated aerosol to a user drawing from the mouth end of the article.

The air flow passage of the aerosol-generating device may be defined within or by a peripheral wall of a housing of the aerosol-generating device. In other words, the airflow passage of the aerosol-generating device may be defined within the thickness of the peripheral wall or by the inner surface of the peripheral wall, or a combination of both. The airflow passage may be defined in part by an inner surface of the peripheral wall, and may be defined in part within a thickness of the peripheral wall. The inner surface of the peripheral wall defines the outer peripheral boundary of the device cavity.

The airflow passage of the aerosol-generating device may extend from an inlet at the mouth end or proximal end of the aerosol-generating device to an outlet facing away from the mouth end of the device. The airflow channel may extend in a direction parallel to a longitudinal axis of the aerosol-generating device. The outlet of the airflow passage is configured such that when a compatible aerosol-generating article is received within the device cavity, the outlet covers the first air entry region of the article.

The airflow passage may be provided with more than one outlet, one for each air entry region provided in an article configured for use with an aerosol-generating device. For example, if the aerosol-generating article comprises a first air inlet region and a second air inlet region, the airflow channel of the corresponding aerosol-generating device may have at least one first outlet for covering the first air inlet region and at least one second outlet for covering the second air inlet region when the aerosol-generating article is fully received within the aerosol-generating device. Thus, the aerosol-generating system may be configured such that, when the aerosol-generating article is received within the device cavity, fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device is established by fluid communication established between the first and second air entry regions of the aerosol-generating article received within the device cavity and the airflow channel of the aerosol-generating device.

When the air flow passage is defined within the peripheral wall of the device, the air flow passage may comprise a first portion extending in an axial direction of the device from the passage inlet and a second portion extending in a transverse or radial direction from an end of the first portion to the passage outlet. Thus, the gas flow channel may comprise an elbow or bend to connect the inlet and outlet of the gas flow channel. If the airflow channel comprises more than one outlet along its length, the airflow channel may comprise further channel portions extending in a transverse direction from the first portion to each of the further outlets. Where the gas flow passage comprises a single outlet, the gas flow passage may comprise an L-bend or elbow.

When the air flow channel is defined by the inner surface of the peripheral wall, the length of the air flow channel may be directly exposed to the device cavity, i.e. the longitudinal sides of the air flow channel may be open to the device cavity. The thickness of the portion of the peripheral wall defining the airflow passage may be less than the thickness of the remainder of the peripheral wall. The portion of the peripheral wall defining the airflow passage may have a diameter greater than the remainder of the peripheral wall. In such embodiments, the air flow channel may be annular such that the air flow channel surrounds the device cavity and the aerosol-generating article received within the device cavity.

In embodiments where the air flow passage is defined by an inner surface of a peripheral wall of the housing, the entire length of the air flow passage may be exposed to or open to the device cavity and thus exposed to the aerosol-generating article received within the device. In such embodiments, to establish fluid communication between the exterior of the aerosol-generating device and the interior of the aerosol-generating article, the air-flow channel is configured to cover all air-entry regions of compatible aerosol-generating articles. In such embodiments, the outlet of the airflow channel may be considered to be the open side of the airflow channel; that is, the sides of the airflow channel are exposed to or open to the device cavity.

The length of the gas flow channel may be less than the length of the device cavity. The length of the airflow passage refers to the longitudinal or axial distance over which the airflow passage extends.

The air flow channel may be configured such that the first outlet of the air flow channel is arranged to align with or overlie a first air entry region of an aerosol-generating article received within the device cavity. The airflow passage may extend from a first inlet at a mouth end of a housing of the aerosol-generating device to a first outlet. The first or any outlet of the airflow passage may be disposed between the distal end and the mouth end of the device lumen.

The first outlet may be located at least about 2mm from the distal end of the device lumen. The first outlet may be located at least about 3mm from the distal end of the device lumen. The first outlet may be located at least about 5mm from the distal end of the device lumen. The first outlet may be located at least about 7mm from the distal end of the device lumen.

The distance of the first outlet from the distal end of the device cavity and the distance of the first air entry zone from the distal end of the device cavity may be similar or the same when the article is received within the device cavity. The distance of the further outlet of the airflow channel from the distal end of the device cavity and the distance of the further air entry zone from the distal end of the device cavity may be similar or the same when the article is received within the device cavity. The distance of the distal end of the airflow channel from the distal end of the device cavity and the distance of the air entry zone from the distal end of the device cavity may be similar or the same when the article is received within the device cavity.

The first outlet may be located no more than about 25mm from the distal end of the device lumen. The first outlet may be located between about 3mm and about 20mm from the distal end of the device lumen. The first outlet may be located between about 5mm and about 18mm from the distal end of the device lumen. The first outlet may be located between about 7mm and about 16mm from the distal end of the device lumen. The airflow channel may not extend beyond the distal end of the device lumen.

The length of the gas flow channel may be about 23mm. The length of the airflow channel may be between about 3mm and about 100 mm. The length of the airflow channel may be between about 8mm and about 70 mm. The length of the airflow channel may be between about 10mm and about 50 mm. The length of the airflow channel may be between about 12mm and about 40 mm. The length of the airflow channel may be between about 12mm and about 40 mm. The length of the airflow channel may be between about 15mm and about 30 mm. The length of the airflow channel may be between about 20mm and about 25 mm.

If a compatible aerosol-generating article comprises a first air entry region located downstream of the rod of aerosol-forming substrate, the length of the air-flow passage may be between about 8mm and about 25 mm. The length of the airflow channel may be between about 10mm and about 15 mm. The length of the airflow channel may be between about 11mm and about 13 mm.

The diameter of the gas flow channel may be between about 0.1mm and about 5mm. The diameter of the gas flow channels may be about 0.5mm to about 4mm. The diameter of the gas flow passages may be about 1mm to about 3mm. The diameter of the gas flow passages may be about 1.5mm to about 2.5mm. The diameters of the gas flow channels and their outlets and inlets may be the same or different.

The "length" of the air flow channel may refer to the length of the air flow channel extending in the longitudinal direction.

There may be a plurality of airflow channels in the aerosol-generating device, each airflow channel having at least one inlet and at least one outlet. Such multiple gas flow passages may be evenly and circumferentially distributed around the device cavity.

The or each airflow passage may comprise a single inlet and a plurality of outlets. In such embodiments, there may be one outlet corresponding to each air entry region provided on an aerosol-generating article configured to be received within an aerosol-generating device.

As mentioned above, an aerosol-generating article according to the invention comprises a rod of aerosol-forming substrate and a filter or downstream section located downstream of the rod of aerosol-forming substrate.

The aerosol-generating article may further comprise an upstream section located at an upstream position of the rod of aerosol-forming substrate. The upstream section may include one or more upstream elements. In some embodiments, the upstream section may comprise an upstream element arranged immediately upstream of the aerosol-generating element. The upstream element may extend from an upstream end of the aerosol-generating substrate to an upstream end of the aerosol-generating article. The upstream element may abut an upstream end of the aerosol-generating article. The upstream element may be referred to as an upstream segment. The aerosol-generating article may comprise an air inlet located at an upstream end of the aerosol-generating article. Where the aerosol-generating article comprises an upstream element, the air inlet may be provided through the upstream element. Air entering through the air inlet may enter the aerosol-generating substrate so as to generate a mainstream aerosol.

The porosity or permeability of the upstream section may advantageously be varied in order to provide a desired total resistance to draw of the aerosol-generating article.

In some embodiments, the upstream section may be formed of a material that is air impermeable. In such embodiments, the aerosol-generating article may be configured such that air flows into the rod of the aerosol-generating substrate through a suitable ventilation means provided in the packaging material.

The upstream section may be made of any material suitable for use in an aerosol-generating article. For example, the upstream element may comprise a core rod of material. Suitable materials for forming the upstream section include filter materials, ceramics, polymeric materials, cellulose acetate, cardboard, zeolites or aerosol generating substrates. Preferably, the upstream section comprises a plug comprising cellulose acetate.

Where the upstream section comprises a plug of material, the downstream end of the plug of material may surround the upstream end of the aerosol-generating substrate. For example, the upstream section may comprise a mandrel comprising cellulose acetate adjacent the upstream end of the aerosol-generating substrate. This may advantageously help to hold the aerosol-generating substrate in place.

Where the upstream section comprises a plug of material, the downstream end of the plug of material may be spaced from the upstream end of the aerosol-generating substrate. The upstream element may comprise a plug of fibrous filter material.

The upstream section may have a length of at least about 1 millimeter. For example, the upstream section may have a length of at least about 2 millimeters, at least about 4 millimeters, or at least about 6 millimeters.

The upstream section may have a length of no more than about 15 millimeters. For example, the upstream segment may have a length of no more than about 12 millimeters, no more than about 10 millimeters, or no more than about 8 millimeters.

The upstream section may have a length between about 1 millimeter and about 15 millimeters. For example, the upstream section may have a length of between about 2 millimeters and about 12 millimeters, between about 4 millimeters and about 10 millimeters, or between about 6 millimeters and about 8 millimeters.

The upstream section or element may comprise a hollow tubular section.

The filter or downstream section may comprise a mouthpiece segment containing a plug of filtration material and a hollow tubular segment located at a position between the rod of aerosol-forming substrate and the mouthpiece segment. All three elements may be longitudinally aligned. The rod of aerosol-forming substrate may comprise at least one aerosol former. The hollow tubular section may be a support section or a cooling section. The hollow tubular section may be located or located immediately downstream of the aerosol-forming substrate.

The filter or downstream section may comprise a mouthpiece segment containing a plug of filtration material and an aerosol-cooling segment (or element) located at a position between the rod and the mouthpiece segment of the aerosol-forming substrate. All three elements may be longitudinally aligned.

The mouthpiece section may comprise a hollow tubular section. The mouthpiece segment may be a hollow tubular segment. The mouthpiece segment may be a plug of filter material.

As used herein, an "aerosol-cooling element" may refer to a component of an aerosol-generating article that is positioned downstream of an aerosol-forming substrate such that, in use, an aerosol formed from volatile compounds released from the aerosol-forming substrate passes through and is cooled by the aerosol-cooling element before being inhaled by a user. The aerosol-cooling element has a large surface area but causes a low pressure drop. The aerosol-cooling element may function to cool the temperature of the aerosol flow drawn through the element by heat transfer. The constituents of the aerosol will interact with the aerosol-cooling element and lose thermal energy.

The aerosol-cooling element may comprise a sheet material selected from the group consisting of: metal foils, polymeric sheets and substantially non-porous paper or paperboard. In some embodiments, the aerosol-cooling element may comprise a sheet material selected from the group consisting of: polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose Acetate (CA), and aluminum foil.

After consumption, the aerosol-generating article is typically disposed of. It may be advantageous for the elements forming the aerosol-generating article to be biodegradable. Thus, it may be advantageous for the aerosol-cooling element to be formed from a biodegradable material, for example non-porous paper or a biodegradable polymer, such as polylactic acid or

Grades (family of commercially available starch-based copolyesters). In some embodiments, the entire aerosol-generating article is biodegradable or compostable.

In some embodiments, aerosol-generating articles according to the invention may comprise an additional support element (or support section) arranged between and longitudinally aligned with the rod and the hollow tubular or aerosol-cooling section (or element) of the aerosol-forming substrate. In more detail, the support element (or support section) may be disposed immediately downstream of the rod and immediately upstream of the hollow tubular section or aerosol-cooling element. The additional support elements or segments may be tubular.

The packaging material of the aerosol-generating article may comprise a gas impermeable material. The packaging material of the aerosol-generating article may comprise an airtight material. By providing an aerosol-generating article with an air-impermeable or air-tight material, when the upstream end of the aerosol-generating article is blocked when inserted into the device cavity or heating chamber of the aerosol-generating device, it is ensured that air must be drawn through the first air entry region in order for air to enter the aerosol-generating article. In other words, it is ensured that the first air entry region may define a main and only air intake portion of the article through which air may be drawn into the article.

The expression "air-tight material" or "air-tight material" is used throughout the present specification to mean a material that does not substantially allow fluids, in particular air and fumes, to pass through voids or pores in the material. For example, if the packaging material is formed of a material that is air-tight and aerosol particles, the air and aerosol particles that are drawn into the article cannot flow through the material of the packaging material. In contrast, the term "porous" is used herein to refer to a material that provides a plurality of pores or openings that allow air to pass through the material.

By providing the packaging material with an air-impermeable material, air can only enter the interior of the aerosol-generating article via a first air entry region provided in the packaging material when the article is received within the aerosol-generating device.

The first air entry region may be located at a (first) position along the aerosol-generating article. The first air entry region of the aerosol-generating article may be located along the rod of the aerosol-forming substrate. The first air entry region may be located around a rod of aerosol-forming substrate. The first air entry region of the aerosol-generating article may be located at a position along the rod of the aerosol-forming substrate.

The first air entry zone may be located at a position downstream of the rod of aerosol-forming substrate. The first air entry zone may be located downstream of, or at least 1mm from, the rod of aerosol-forming substrate.

The first air entry region of the aerosol-generating article may be located along the hollow tubular section. The first air entry region may be located around the hollow tube section. The first air entry region of the aerosol-generating article may be located at a position along the hollow tubular section.

The first air entry region of the aerosol-generating article may be located along the support section. The first air entry zone may be located around the support section. The first air entry region of the aerosol-generating article may be located at a position along the support section. The support section may be a hollow support section.

The aerosol-generating article may extend between an upstream end and a downstream end. The downstream end of the article may coincide with the downstream end of the rod of aerosol-forming substrate. In other words, the downstream end of the rod of aerosol-forming substrate may define the downstream end of the aerosol-generating article.

The first air entry zone may be located at least about 2mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 3mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 4mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 5mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 6mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 7mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 8mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 9mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 10mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located at least about 12mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located about 20mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 15mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 14mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 13mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 12mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 10mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 9mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 8mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 6mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located about 5mm or less downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located between about 2mm and about 20mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 3mm and about 15mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 4mm and about 12mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located between about 2mm and about 15mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 3mm and about 12mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 5mm and about 10mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located between about 2mm and about 12mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 3mm and about 10mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 5mm and about 8mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located between about 2mm and about 10mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 3mm and about 9mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 5mm and about 8mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located between about 2mm and about 8mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 2mm and about 6mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 2mm and about 5mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located between about 10mm and about 20mm downstream of the upstream end of the rod of aerosol-forming substrate. The first air entry zone may be located between about 12mm and about 15mm downstream of the upstream end of the rod of aerosol-forming substrate.

The first air entry zone may be located along an upstream half of a rod of aerosol-forming substrate. By positioning the first air entry zone along the upstream half of the rod of aerosol-forming substrate, air drawn through the first air entry zone may be drawn through a substantial length of the rod of aerosol-forming substrate in order to optimise aerosol generation and effectively use the aerosol-forming substrate.

The first air entry region may be located along a downstream half of a rod of aerosol-forming substrate. The first air entry zone may be located along an upstream half of the hollow tubular section. The first air entry zone may be located along an upstream half of the support section. The first air entry zone may be located along a downstream half of the hollow tubular section. The first air entry zone may be located along a downstream half of the support section.

Throughout the specification, when it is stated that the air entry region is or may be located along a certain component of the aerosol-generating article, this refers to the fact that the air entry region is located on a portion of the wrapper which covers such component of the aerosol-generating article. For example, if the air entry region is located along the rod of the aerosol-forming substrate, this refers to the fact that the air entry region is located on a portion of the wrapper that covers the rod of the aerosol-forming substrate.

The term "upstream half" refers to a region or portion of an element between the upstream end of the element and the midpoint of the element. The term "downstream half" refers to a region or portion of the element between the downstream end of the element and the midpoint of the element.

The aerosol-generating article may be provided with an additional air entry region to provide an additional function to the first air entry region. The aerosol-generating article may comprise a second air entry region located on the wrapper. Such a second air entry region may be configured to provide ventilation for the aerosol-generating article during use within the device as a ventilation zone, while the first air entry region serves as an air entry region for the article. In addition, an air entry zone may be provided to provide further ventilation of the article during normal and consistent use.

The second air entry region may be located at a (second) position along the aerosol-generating article. The second air entry zone may be located on the packaging material at a location downstream of the first air entry zone. The second air entry region may be provided at the same location along the aerosol-generating article as the first air entry region. For example, if the first air entry zone is provided along the rod of the aerosol-forming substrate, the second air entry zone may be provided at a location along the rod of the aerosol-forming substrate downstream of the first air entry zone.

The second air entry zone may be located downstream of the stem of aerosol-forming substrate. The second air entry zone may be located downstream of the downstream end of the rod of aerosol-forming substrate. The second air entry zone may be located along a filter or downstream section of the aerosol-generating article. The second air entry region may be located along the hollow tubular section. The second air entry region may be located along the support section.

The second air entry zone may be located at least about 1mm downstream of the stem of the aerosol-forming substrate. That is, the second air entry region may be located at least 1mm downstream of the downstream end of the rod of aerosol-forming substrate. The second air entry zone may be located at least about 2mm downstream of the stem of the aerosol-forming substrate. The second air entry zone may be located at least about 3mm downstream of the rod of aerosol-forming substrate.

The second air entry zone may be located about 8mm or less downstream of the rod of aerosol-forming substrate. The second air entry zone may be located about 7mm or less downstream of the stem of the aerosol-forming substrate. The second air entry zone may be located about 6mm or less downstream of the stem of the aerosol-forming substrate.

The second air entry zone may be located between about 1mm and about 8mm downstream of the rod of aerosol-forming substrate. The second air entry region may be located between about 2mm and about 7mm downstream of the stem of the aerosol-forming substrate. The second air entry zone may be located between about 2mm and about 6mm downstream of the rod of aerosol-forming substrate. The second air entry region may be located between about 3mm and about 6mm downstream of the stem of the aerosol-forming substrate.

The second air entry zone may be located at least about 1mm downstream of the upstream end of the hollow tubular section. The second air entry zone may be located at least about 2mm downstream of the upstream end of the hollow tubular section. The second air entry zone may be located at least about 3mm downstream of the upstream end of the hollow tubular section.

The second air entry zone may be located about 8mm or less downstream of the upstream end of the hollow tubular section. The second air entry zone may be located about 7mm or less downstream of the upstream end of the hollow tubular section. The second air entry zone may be located about 6mm or less downstream of the upstream end of the hollow tubular section.

The second air entry zone may be located between about 1mm and about 8mm downstream of the upstream end of the hollow tubular section. The second air entry zone may be located between about 2mm and about 7mm downstream of the upstream end of the hollow tubular section. The second air entry zone may be located between about 2mm and about 6mm downstream of the upstream end of the hollow tubular section. The second air entry zone may be located between about 3mm and about 6mm downstream of the upstream end of the hollow tubular section.

The second air entry zone may be located at least about 1mm downstream of the upstream end of the support section. The second air entry zone may be located at least about 2mm downstream of the upstream end of the support section. The second air entry zone may be located at least about 3mm downstream of the upstream end of the support section.

The second air entry zone may be located about 8mm or less downstream of the upstream end of the support section. The second air entry zone may be located about 7mm or less downstream of the upstream end of the support section. The second air entry zone may be located about 6mm or less downstream of the upstream end of the support section.

The second air entry zone may be located between about 1mm and about 8mm downstream of the upstream end of the support section. The second air entry zone may be located between about 2mm and about 7mm downstream of the upstream end of the support section. The second air entry zone may be located between about 2mm and about 6mm downstream of the upstream end of the support section. The second air entry zone may be located between about 3mm and about 6mm downstream of the upstream end of the support section.

As mentioned above, the second air entry region may be located along the rod of the aerosol-forming substrate. The second air entry zone may be located at least about 3.5mm downstream of the upstream end of the rod of aerosol-forming substrate. The second air entry zone may be located at least about 4mm downstream of the upstream end of the rod of aerosol-forming substrate. The second air entry zone may be located at least about 6.5mm downstream of the upstream end of the rod of aerosol-forming substrate.

The second air entry zone may be located about 20mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The second air entry zone may be located about 16mm or less downstream of the upstream end of the rod of aerosol-forming substrate. The second air entry zone may be located about 12mm or less downstream of the upstream end of the rod of aerosol-forming substrate.

The second air entry region may be located between about 3.5mm and about 20mm downstream of the upstream end of the rod of aerosol-forming substrate. The second air entry region may be located between about 4mm and about 16mm downstream of the upstream end of the rod of aerosol-forming substrate. The second air entry region may be located between about 6.5mm and about 12mm downstream of the upstream end of the rod of aerosol-forming substrate.

The second air entry zone may be located at least about 1.5mm downstream of the first air entry zone. The second air entry zone may be located at least about 2mm downstream of the first air entry zone. The second air entry zone may be located at least about 3mm downstream of the first air entry zone.

The second air entry zone may be located at least about 10mm downstream of the first air entry zone. The second air entry zone may be located at least about 12mm downstream of the first air entry zone. In such embodiments, the second air entry region may be located downstream of the stem of the aerosol-forming substrate.

The second air entry zone may be located about 20mm or less downstream of the first air entry zone. The second air entry zone may be located about 18mm or less downstream of the first air entry zone. The second air entry zone may be located about 16mm or less downstream of the first air entry zone.

The second air entry zone may be located between about 1.5mm and about 20mm downstream of the first air entry zone. The second air entry zone may be located between about 2mm and about 18mm downstream of the first air entry zone. The second air entry zone may be located between about 3mm and about 16mm downstream of the first air entry zone.

The second air entry region may be located along an upstream half of the rod of aerosol-forming substrate. The second air entry region may be located along a downstream half of the rod of aerosol-forming substrate. The second air entry zone may be located along an upstream half of the hollow tubular section. The second air entry zone may be located along an upstream half of the support section. The second air entry zone may be located along a downstream half of the hollow tubular section. The second air entry region may be located along a downstream half of the support section.

The air entry region may comprise one or more rows of apertures or perforations extending through the wrapper of the aerosol-generating article. The apertures or perforations of the air entry zone may extend through a downstream section of the filter or aerosol-generating article. The apertures or perforations of the air entry zone may extend through the peripheral wall of the hollow tubular section of the article. The apertures or perforations of the air entry zone may extend through the peripheral wall of the support section of the article, particularly if the support section is hollow.

The air entry zone may include only one row of apertures or perforations. A row of apertures or perforations may comprise between 8 and 30 apertures or perforations. A row of apertures or perforations may comprise between 10 and 20 apertures or perforations. The air entry region may surround the aerosol-generating article. The air entry region may surround a rod of aerosol-forming substrate. The air entry region may surround the hollow tubular section. The air entry region may surround the support section.

The perforations of the air entry zone may be of uniform size. Alternatively, the size of the perforations may be different. By varying the number and size of the perforations, the amount of outside air entering the hollow tubular segment can be regulated when a consumer draws on the mouthpiece of the aerosol-generating article during use. Thus, the ventilation or air intake level of the aerosol-generating article may advantageously be adjusted. Preferably, the perforations are circular.

The air entry perforations may be formed using any suitable technique, for example by laser techniques, mechanical perforation of a hollow tubular section or support section as part of the aerosol-generating article, or pre-perforation of a hollow tubular section or support section prior to its combination with other elements to form the aerosol-generating article. Preferably, the perforations are formed by in-line laser perforation.

Furthermore, the inventors have found that in aerosol-generating articles according to the invention, the cooling and dilution effect caused by the ingress of ventilation air at a location along the conduit defined by the hollow tubular section described above has a surprisingly reduced effect on the production and delivery of phenolic-containing materials.

The air entry zone may comprise one or more rows of perforations formed through the peripheral wall of the hollow tubular section. As mentioned above, the second air entry region may be a vented region. Preferably, the ventilation zone comprises only one row of perforations. This is understood to be advantageous because aerosol nucleation may be further enhanced by condensing the cooling effect created by ventilation on the short portions of the cavity defined by the hollow tubular section. This is because faster and more intense cooling of the volatile material flow is expected to be particularly beneficial in forming new aerosol particle nuclei.

Preferably, one or more rows of perforations are arranged circumferentially around the wall of the hollow tube. Where the ventilation zone comprises two or more rows of perforations formed through the peripheral wall of the hollow tubular section, the rows are spaced longitudinally from one another along the hollow tubular section.

The radius of the air entry perforations or apertures may be at least about 0.05mm. The radius of the air entry perforations or apertures may be at least about 0.06mm. The radius of the air entry perforations or apertures may be at least about 0.1mm. The radius of the air entry perforations may be between about 0.06mm and about 0.1mm.

The equivalent diameter of at least one of the ventilation or air entry perforations is preferably at least about 100 microns. Preferably, at least one of the vent perforations has an equivalent diameter of at least about 150 microns. Even more preferably, at least one of the vent perforations has an equivalent diameter of at least about 200 microns. Additionally, or alternatively, the equivalent diameter of at least one of the ventilation perforations is preferably less than about 500 microns. More preferably, at least one of the vent perforations has an equivalent diameter of less than about 450 microns. Even more preferably, the equivalent diameter of at least one of the ventilation perforations is less than about 400 microns. The term "equivalent diameter" is used herein to mean the diameter of a circle having the same surface area as the cross-section of the ventilation perforations. The cross-section of the ventilation perforations may have any suitable shape. However, circular ventilation perforations are preferred.

The ventilation or air entry perforations may be of uniform size. Alternatively, the size of the ventilation perforations may be different. By varying the number and size of the ventilation perforations, the amount of outside air entering the hollow tubular segment can be regulated when a consumer draws on the mouthpiece of the aerosol-generating article during use. Thus, advantageously the ventilation level of the aerosol-generating article can be adjusted.

The air entry region may comprise a substantially porous portion of the packaging material of the aerosol-generating article. Such porous portions may be defined in an air-tight or air-tight wrapper of the aerosol-generating article, or may be defined by a different material forming part of the wrapper of the aerosol-generating article. Such porous portions may be defined by a pattern of pores defined in the wrapper. Such porous portions may define a first air entry zone or a second air entry zone. Thus, the first air entry zone or the second air entry zone may have the porous nature of such porous portions.

Such porous portions of the packaging material may have a relatively high porosity relative to the remainder of the packaging material of the aerosol-generating article. The porosity of such porous portions may be at least about 3000 Coresta (Coresta) units (CU). The porosity of such porous portions may be at least about 5000 korassia units (CU). Such porous portions may have a porosity of less than about 25000 koraster units (CU). Such porous portions may have a porosity of less than about 20000 korasst units (CU). The porosity of such porous portions may be between about 3000CU and about 25000 CU. The porosity of such porous portions may be between about 5000CU and about 20000 CU.

The width of the air entry zone (first air entry zone, second air entry zone, or any air entry zone) may be at least about 1mm. The width of the air entry region may be at least about 3mm. The width of the air entry region may be at least about 5mm. The "width" of the air entry region refers to the size of the air entry region in the axial or longitudinal direction of the aerosol-generating article. Thus, the "width" of the air entry region may be referred to as the "length" of the air entry region.

The width of the first air entry region may be greater than the width of the second air entry region. This enables the first air entry region to function as a primary air inlet for the aerosol-generating article, while the second or subsequent air entry region may function as a secondary air inlet region or ventilation region, when received within a compatible aerosol-generating device.

Such a relatively wide air entry zone may be formed by a porous portion of the packaging material having a relatively high porosity (as described above), a plurality of perforation lines or one relatively wide perforation line.

By providing a wide air entry region, such as the first air entry region, there will be more surface area of the first air entry region overlapping or aligned with the outlet of the airflow channel of the aerosol-generating device. This will therefore reliably ensure that fluid communication is established between the exterior of the aerosol-generating device and the interior of an aerosol-generating article received within the device, enabling the consumer to properly consume the article. Having a relatively wide air entry region may account for any manufacturing inaccuracies in the air entry region, which may affect the alignment of the outlet of the airflow channel of the device with the air entry region.

The air entry region may completely or partially surround the aerosol-generating article. The air entry region may be located around the aerosol-generating article.

The aerosol-generating article may comprise a first air entry region and a second air entry region located along the rod of the aerosol-forming substrate. The aerosol-generating article may comprise a first air entry region located along the rod of the aerosol-forming substrate and a second air entry region located downstream of the rod of the aerosol-forming substrate. The aerosol-generating article may comprise a first air entry region located along the rod of the aerosol-forming substrate and a second air entry region located along the hollow tubular section. The aerosol-generating article may comprise a first air entry region located along the rod of the aerosol-forming substrate and a second air entry region located along the support section.

Each air entry region may provide or allow a certain level of air entry into the interior of the aerosol-generating article. The air entry level may refer to the amount of fluid that is allowed to enter through the air entry region in order to enter the interior of the aerosol-generating article. The air intake level may be expressed in air volume in cubic millimeters, which may be entered via the air intake zone over a period of time in seconds. The air intake level can be expressed as a mass flow rate in grams or kilograms per second, or a volume flow rate in milliliters or liters per second.

The level of air ingress into the interior of the aerosol-generating article through the first air entry region may be configured to be greater than the level of air ingress into the interior of the aerosol-generating article through the second air entry region. This is to ensure that, during use, when the aerosol-generating article is received in the aerosol-generating device, an appropriate amount of air flows through the first air entry region to act as the primary air entry region for the article, while the second air entry region can provide ventilation for the article.

The level of air ingress through the air entry region can be defined as the volumetric flow rate. The level of air ingress, i.e. the volume flow, into the interior of the aerosol-generating article through the first air entry region may be at least about 10% higher than the level of air ingress (volume flow) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volume flow, into the interior of the aerosol-generating article through the first air entry region may be at least about 20% higher than the level of air ingress (volume flow) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volumetric flow rate, into the interior of the aerosol-generating article through the first air entry region may be at least about 30% higher than the level of air ingress (volumetric flow rate) into the interior of the aerosol-generating article through the second air entry region.

The level of air ingress, i.e. the volume flow, into the interior of the aerosol-generating article through the first air entry region may be less than about 300% higher than the level of air ingress (volume flow) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volumetric flow rate, into the interior of the aerosol-generating article through the first air entry region may be less than about 200% higher than the level of air ingress (volumetric flow rate) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volumetric flow rate, into the interior of the aerosol-generating article through the first air entry region may be less than about 100% higher than the level of air ingress (volumetric flow rate) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volume flow, into the interior of the aerosol-generating article through the first air entry region may be less than about 90% higher than the level of air ingress (volume flow) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volume flow, into the interior of the aerosol-generating article through the first air entry region may be less than about 75% higher than the level of air ingress (volume flow) into the interior of the aerosol-generating article through the second air entry region. The level of air ingress, i.e. the volume flow, into the interior of the aerosol-generating article through the first air entry region may be less than about 60% higher than the level of air ingress (volume flow) into the interior of the aerosol-generating article through the second air entry region.

Over a period of time, from a volume of air entering the aerosol-generating device through the air flow channel or channels, a first proportion of such volume of inlet air may enter the interior of the aerosol-generating article through the first air entry region, and a second proportion of such volume of inlet air may enter the interior of the aerosol-generating article through the second air entry region. For example, during the time period T, a volume V of air may enter the aerosol-generating device, and then a first proportion V, expressed as a percentage of V, may enter the interior of the aerosol-generating article through the first air entry region, while a second proportion V may enter the interior of the aerosol-generating article through the second air entry region.

At least about 50% of the total volume of air admitted to the aerosol-generating device over a period of time may pass through the first air entry zone into the interior of the aerosol-generating article. At least about 55% of the total volume of air admitted to the aerosol-generating device over a period of time may pass through the first air entry region into the interior of the aerosol-generating article. At least about 60% of the total volume of air admitted to the aerosol-generating device over a period of time may pass through the first air entry region into the interior of the aerosol-generating article. At least about 70% of the total volume of air admitted to the aerosol-generating device over a period of time may pass through the first air entry zone into the interior of the aerosol-generating article. At least about 75% of the total volume of air admitted to the aerosol-generating device over a period of time may pass through the first air entry region into the interior of the aerosol-generating article.

About 50% or less of the total volume of air admitted to the aerosol-generating device over a period of time may pass through the second air entry zone into the interior of the aerosol-generating article. About 45% or less of the total volume of air admitted to the aerosol-generating device over a period of time may enter the interior of the aerosol-generating article through the second air entry region. About 40% or less of the total volume of air admitted to the aerosol-generating device over a period of time may enter the interior of the aerosol-generating article through the second air entry region. About 30% or less of the total volume of air admitted to the aerosol-generating device over a period of time may enter the interior of the aerosol-generating article through the second air entry region. About 25% or less of the total volume of air admitted to the aerosol-generating device over a period of time may enter the interior of the aerosol-generating article through the second air entry region.

About 50% of the total volume may enter the interior of the aerosol-generating article through the first air entry region and about 50% of the total volume may enter the interior of the aerosol-generating article through the second air entry region, relative to the total volume of air entering the aerosol-generating device over a period of time.

About 55% of the total volume that can enter the interior of the aerosol-generating article through the first air entry region, and 45% of the total volume that can enter the interior of the aerosol-generating article through the second air entry region, relative to the total volume of air that enters the aerosol-generating device over a period of time.

About 60% of the total volume may enter the interior of the aerosol-generating article through the first air entry region and about 40% of the total volume may enter the interior of the aerosol-generating article through the second air entry region, relative to the total volume of air entering the aerosol-generating device over a period of time.

About 70% of the total volume may enter the interior of the aerosol-generating article through the first air entry region and about 30% of the total volume may enter the interior of the aerosol-generating article through the second air entry region, relative to the total volume of air entering the aerosol-generating device over a period of time.

About 75% of the total volume that can enter the interior of the aerosol-generating article through the first air entry region, and about 25% of the total volume that can enter the interior of the aerosol-generating article through the second air entry region, relative to the total volume of air that enters the aerosol-generating device over a period of time.

Similarly, a certain volume flow may flow through the airflow channel or channels of the aerosol-generating device before the air leaves the airflow channel towards the aerosol-generating device. Depending on such an intake volume flow (or an airflow channel volume flow existing in the airflow channel before the outlet), a first proportion of such an intake volume flow may flow through the first air entry region and a second proportion of such an intake volume flow may flow through the second air entry region. For example, the volumetric flow rate VF may flow through the flow passage, then a first proportion of VF, expressed as a percentage of VF, may flow through the first air entry zone, and a second proportion of VF may flow through the second air entry zone.

At least about 50% of the inlet volumetric flow rate of air flowing through the airflow passage of the aerosol-generating device relative to such inlet volumetric flow rate may flow through the first air entry region. At least about 55% of such inlet volumetric flow rate may flow through the first air entry region relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device. At least about 60% of such inlet volumetric flow rate, relative to the inlet volumetric flow rate through the airflow passage of the aerosol-generating device, may flow through the first air entry region. At least about 70% of such inlet volumetric flow rate, relative to the inlet volumetric flow rate through the airflow passage of the aerosol-generating device, may flow through the first air entry region. At least about 75% of the inlet volumetric flow rate of air flowing through the airflow passage of the aerosol-generating device relative to such inlet volumetric flow rate may flow through the first air entry region.

About 50% or less of such inlet volumetric flow rate may flow through the second air entry region relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device. About 45% or less of such inlet volumetric flow rate may flow through the second air entry region relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device. About 40% or less of such inlet volumetric flow rate may flow through the second air entry region relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device. About 30% or less of such inlet volumetric flow rate may flow through the second air entry region relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device. About 25% or less of such inlet volumetric flow rate may flow through the second air entry region relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device.

About 50% of such inlet volumetric flow rate may flow through the first air entry region and about 50% of such inlet volumetric flow rate may flow through the second air entry region, relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device.

Relative to an intake volumetric flow rate through the airflow passage of the aerosol-generating device, about 55% of such intake volumetric flow rate may flow through the first air entry region and about 45% of such intake volumetric flow rate may flow through the second air entry region.

Relative to an intake volumetric flow rate through the airflow passage of the aerosol-generating device, about 60% of such intake volumetric flow rate may flow through the first air entry region and about 40% of such intake volumetric flow rate may flow through the second air entry region.

About 70% of such inlet volumetric flow rate may flow through the first air entry region and about 30% of such inlet volumetric flow rate may flow through the second air entry region, relative to the inlet volumetric flow rate through the air flow passage of the aerosol-generating device.

Relative to an intake volumetric flow rate through the airflow passage of the aerosol-generating device, about 75% of such intake volumetric flow rate may flow through the first air entry region and about 25% of such intake volumetric flow rate may flow through the second air entry region.

Throughout this specification, the term "ventilation level" may be used to denote the volume ratio between the airflow entering the aerosol-generating article via the air entry region (air entry airflow) and the airflow exiting the aerosol-generating article via the mouth end or downstream end. The greater the level of ventilation, the higher the dilution of the aerosol stream delivered to the consumer. The ventilation level is measured independently on the aerosol-generating article, i.e. without inserting the aerosol-generating article into a suitable aerosol-generating device adapted to heat the aerosol-forming substrate.

The level of ventilation provided by the first air entry zone may be measured by blocking all other air entry zones (if present) and drawing air from the mouth end of the aerosol-generating article so that air may flow through the front or upstream end of the aerosol-generating article and the first air entry zone into the aerosol-generating article. The level of ventilation provided by the first air entry zone may be defined as the ratio between the flow rate of air (airflow) entering the aerosol-generating article through the first air entry zone and the flow rate of air exiting the aerosol-generating article at the mouth end.

The level of ventilation provided by the second air entry region may be measured by blocking all other air entry regions (if present) and drawing air from the mouth end of the aerosol-generating article so that air may flow through the front or upstream end of the aerosol-generating article and the second air entry region into the aerosol-generating article. The level of ventilation provided by the second air entry zone may be defined as the ratio between the flow of air (airflow) entering the aerosol-generating article through the second air entry zone and the flow of air exiting the aerosol-generating article at the mouth end.

The total ventilation level of the aerosol-generating article may be measured by not blocking any air entry region present in the aerosol-generating article and drawing air in from the mouth end of the aerosol-generating article so that air may flow through the front or upstream end of the aerosol-generating article and the air entry region into the aerosol-generating article. The total ventilation level of the aerosol-generating article may be defined as the ratio of the sum of the air flow rates into the aerosol-generating article through each air entry region to the flow rate of air exiting the aerosol-generating article at the mouth end.

The level of ventilation provided to the aerosol-generating article by the first air entry region may be at least about 10%. The level of ventilation provided by the first air entry zone may be at least about 20%. The level of ventilation provided by the first air entry zone may be at least about 25%. The level of ventilation provided by the first air entry zone may be at least about 50%. The level of ventilation provided by the first air entry zone may be at least about 75%.

The level of ventilation provided to the aerosol-generating article by the second air entry region may be at least about 10%. The level of ventilation provided by the second air entry zone may be at least about 20%. The level of ventilation provided by the second air entry zone may be at least about 25%. The level of ventilation provided by the second air entry region may be at least about 50%. The level of ventilation provided by the second air entry zone may be at least about 75%.

The level of ventilation provided by the first air entry zone or the second air entry zone may be about 75% or less. The ventilation level provided by the first air entry zone or the second air entry zone may be about 60% or less. The level of ventilation provided by the first air entry zone or the second air entry zone may be about 50% or less.

The ventilation level provided by the first air entry zone or the second air entry zone may be between about 10% and about 75%. The ventilation level provided by the first air entry zone or the second air entry zone may be between about 30% and about 60%.

The aerosol-generating article may typically have a total ventilation level of at least about 10%, preferably at least about 20%.

The aerosol-generating article may have a total ventilation level of at least about 20%, or about 25%, or about 30%. The aerosol-generating article may have a total ventilation level of at least about 35%. The aerosol-generating article may have a total ventilation level of less than about 60%. The aerosol-generating article may have a total ventilation level of less than about 50% or less than about 40%. The aerosol generating article may have a total ventilation level of between about 25% to about 60%.

The aerosol-generating article may have a total ventilation level of from about 10% to about 90%. The aerosol generating article may have a total ventilation level of from about 20% to about 80%. The aerosol-generating article may have a total ventilation level of from about 25% to about 60%. The aerosol-generating article may have a total ventilation level of from about 30% to about 50%. The aerosol generating article may have a total ventilation level of from about 30% to about 40%.

The aerosol generating article may have a total ventilation level of from about 28% to about 42%. The aerosol-generating article may have a ventilation level of about 35%. The inventors have surprisingly found that the dilution effect on aerosols, in particular as can be assessed by measuring the delivery effect on glycerol contained in aerosol-forming substrates as aerosol former, is advantageously minimized when the ventilation level is between about 30% and about 50%. In particular, ventilation levels between about 35% to about 42% have been found to produce particularly satisfactory glycerol delivery values. At the same time, the degree of nucleation and hence delivery of nicotine and aerosol former (e.g. glycerol) is increased.

The first air entry region may function as a first or primary air entry region, while the second air entry region may function as a ventilation region of the aerosol-generating article. This is because the first air entry region will be configured as the first entry point of air when the aerosol-generating article is located within the device cavity, and may be configured to receive the highest level of air compared to any other air entry region provided on the wrapper of the article.

As mentioned above, the first air entry region will ensure compatibility between the aerosol-generating article and the aerosol-generating device by defining a primary air entry region of the article, while the second air entry region will provide ventilation for the aerosol-generating article during normal use in which the aerosol-generating article is received within the device. During normal use, all of the air entry region may be located within the device cavity or heating chamber of the aerosol-generating device. This will prevent the user from inadvertently blocking any air entry area with the hands or lips during normal use, which may negatively impact the user's experience as the article may not be ventilated.

It is advantageous to provide ventilation for the aerosol-generating article during normal use. Without wishing to be bound by theory, it has been found that the temperature drop caused by the cooler, external air entering the hollow tubular section via the ventilation zone, may have a beneficial effect on the nucleation and growth of aerosol particles.

In this scenario, which may be further complicated by coalescence phenomena, the temperature and rate of cooling play a key role in determining how the system responds. Generally, different cooling rates can result in significantly different time behaviors associated with liquid phase (droplet) formation, as the nucleation process is typically nonlinear. Without wishing to be bound by theory, it is hypothesized that cooling may result in a rapid increase in the number concentration of droplets, followed by a strong, transient increase in this growth (nucleation burst). This nucleation burst appears to be more pronounced at lower temperatures. Furthermore, it appears that a higher cooling rate may be beneficial to initiate nucleation earlier. In contrast, a decrease in the cooling rate appears to have a favorable effect on the final size that the aerosol droplets eventually reach.

Thus, the rapid cooling caused by the external air entering the hollow tubular section via the ventilation zone may advantageously be used to promote nucleation and growth of aerosol droplets. At the same time, however, the entry of outside air into the hollow tubular section has the direct disadvantage of diluting the aerosol flow delivered to the consumer.

In addition, it has been found that in aerosol-generating articles according to the present invention, the cooling and dilution effect caused by the ingress of ventilation air at a location along the conduit defined by the hollow tubular section described above has a surprisingly reduced effect on the generation and delivery of phenolic-containing materials.

This is understood to be advantageous because aerosol nucleation may be further enhanced by concentrating the cooling effect created by ventilation on the short portion of the cavity defined by the hollow tubular section. This is because a faster and more intense cooling of the flow of volatile substances from the aerosol-forming substrate is expected to be particularly advantageous for the formation of new nuclei of aerosol particles.

The rod of aerosol-forming substrate preferably has an outer diameter approximately equal to that of the aerosol-generating article.

Preferably, the rod of the aerosol-forming substrate has an outer diameter of at least about 4 millimetres (mm). The rod of aerosol-forming substrate may have an outer diameter of at least about 5mm. The outer diameter of the rod of aerosol-forming substrate may be between about 5 millimetres and about 12 millimetres, for example between about 5 millimetres and about 10 millimetres or between about 6 millimetres and about 8 millimetres. In a preferred embodiment, the rod of aerosol-forming substrate has an outer diameter within 7.2 mm to 10%.

The length of the stem of the aerosol-forming substrate may be between about 5 millimetres and about 100 mm. Preferably, the rod of the aerosol-forming substrate has a length of at least about 5mm, more preferably at least about 7 mm. In addition, or in the alternative, the rod of aerosol-forming substrate preferably has a length of less than about 80 mm, more preferably less than about 65 mm, even more preferably less than about 50 mm. In a particularly preferred embodiment, the rod of the aerosol-forming substrate has a length of less than about 35 mm, more preferably less than 25mm, even more preferably less than about 20 mm. In one embodiment, the rod of aerosol-forming substrate may have a length of about 10 millimetres. In a preferred embodiment, the rod of the aerosol-forming substrate has a length of about 12 mm.

Preferably, the rod of aerosol-forming substrate has a substantially uniform cross-section along the length of the rod. It is particularly preferred that the rod of the aerosol-forming substrate has a substantially circular cross-section.

In a preferred embodiment, the aerosol-forming substrate comprises one or more gathered sheets of homogenised tobacco material. One or more of the sheets of homogenised tobacco material may be textured. As used herein, the term "textured sheet" means a sheet that has been curled, embossed, debossed, perforated or otherwise deformed. The textured sheet for the homogenized tobacco material of the present invention may comprise a plurality of spaced-apart indentations, protrusions, perforations, or combinations thereof. The rod of aerosol-forming substrate may comprise a gathered crimped sheet of homogenised tobacco material circumscribed by a wrapper.

In certain preferred embodiments, the aerosol-forming substrate comprises homogenised plant material, preferably homogenised tobacco material.

As used herein, the term "homogenized plant material" encompasses any plant material formed from agglomeration of plant particles. For example, a sheet or web of homogenized tobacco material for use in the aerosol-forming substrate of the invention may be formed by agglomerating particles of tobacco material obtained by comminuting, grinding or grinding a plant material and optionally one or more of tobacco lamina and tobacco stem. Homogenized plant material may be produced by casting, extrusion, paper making processes, or any other suitable process known in the art.

The homogenized plant material may be provided in any suitable form. For example, the homogenized plant material may be in the form of one or more sheets. As used herein with reference to the present invention, the term "sheet" describes a layered element having a width and length substantially greater than its thickness.

Alternatively or additionally, the homogenized plant material may be in the form of a plurality of pellets or granules.

Alternatively or additionally, the homogenized plant material may be in the form of a plurality of strips, strips or pieces. As used herein, the term "sliver" describes an elongated member material having a length that is substantially greater than its width and thickness. The term "sliver" should be taken to include strips, pieces and any other homogenized plant material having a similar form. The homogenized plant material strand may be formed from a sheet of homogenized plant material, for example by cutting or shredding, or by other methods, for example by extrusion methods.

As used herein, the term "crimped sheet" is intended to be synonymous with the term "corrugated sheet" and refers to a sheet having a plurality of substantially parallel ridges or corrugations. Preferably, the crimped sheet of homogenised tobacco material has a plurality of ridges or corrugations that are substantially parallel to the cylindrical axis of the rod according to the invention. This advantageously promotes the gathering of the crimped sheet of homogenised tobacco material to form a rod. However, it will be appreciated that the crimped sheet of homogenised tobacco material for use in the present invention may alternatively or additionally have a plurality of substantially parallel ridges or corrugations disposed at acute or obtuse angles to the cylindrical axis of the rod. The sheet of homogenised tobacco material for use in the rod of the article of the invention may be textured substantially uniformly over substantially its entire surface. For example, a crimped sheet of homogenised tobacco material for use in the manufacture of rods for aerosol-generating articles according to the invention may comprise a plurality of substantially parallel ridges or corrugations that are substantially evenly spaced across the width of the sheet.

The sheet or web of homogenised tobacco material for use in the present invention may have a tobacco content of at least about 40 wt% by dry weight, more preferably at least about 60 wt% by dry weight, more preferably at least about 70 wt% by dry weight, most preferably at least about 90 wt% 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 intrinsic binders, one or more extrinsic binders, i.e. tobacco extrinsic binders, or a combination thereof, to aid in the agglomeration of the particulate tobacco. Alternatively or additionally, the sheet of homogenised tobacco material for use in the aerosol-forming substrate may comprise other additives including, but not limited to, tobacco and non-tobacco fibres, aerosol-formers, humectants, plasticisers, flavourants, fillers, aqueous and non-aqueous solvents and combinations thereof.

The homogenized vegetable or tobacco material includes tobacco particles or material, and non-tobacco vegetable flavoring particles. The non-tobacco plant flavour particles may be selected from one or more of the following: ginger granules, rosemary granules, eucalyptus granules, clove granules and anise granules.

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

Suitable non-tobacco fibers for inclusion in a sheet or web of homogenised tobacco material for an aerosol-forming substrate are known in the art and include, but are not limited to: cellulose fibers; softwood fibers; hardwood fibers; jute fibers and combinations thereof. Prior to inclusion in the sheet of homogenised tobacco material for use in the aerosol-forming substrate, the non-tobacco fibres may be treated by suitable methods known in the art including, but not limited to: mechanically pulping; refining; chemical pulping; bleaching; sulfate pulping; and combinations thereof.

In other embodiments of the invention, the aerosol-forming substrate may comprise a gel composition comprising an alkaloid compound. The aerosol-forming substrate may comprise a gel composition comprising nicotine. The aerosol-forming substrate may comprise a nicotine-free gel composition.

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

Advantageously, the stable gel composition comprising nicotine provides a predictable composition form upon storage or shipment from the manufacturer to the consumer. The stable gel composition comprising nicotine substantially retains its shape. The stable gel composition comprising nicotine releases substantially no liquid phase upon storage or shipment from the manufacturer to the consumer. A stable gel composition comprising nicotine may provide a simple consumable design. The consumable may not necessarily be designed to receive a liquid, and thus a wider range of materials and container configurations may be contemplated.

The gel compositions described herein may be combined with an aerosol-generating device to provide nicotine aerosol to the lungs at an inhalation rate or air flow rate in a range of inhalation rates or air flow rates for conventional smoking regimes. The aerosol-generating device may heat the gel composition continuously. The consumer may take multiple inhalations or "puffs," where each "puff" delivers an amount of nicotine aerosol. The gel composition is capable of delivering a high nicotine/low Total Particulate Matter (TPM) aerosol to a consumer when heated, preferably in a continuous manner.

The phrase "stable gel phase" or "stable gel" refers to a gel that substantially retains its shape and quality when exposed to various environmental conditions. The stable gel may not substantially release (sweat) or absorb moisture when exposed to standard temperature and pressure while the relative humidity changes from about 10% to about 60%. For example, a stable gel may substantially retain its shape and quality when exposed to standard temperature and pressure while the relative humidity changes from about 10% to about 60%.

The gel composition includes an alkaloid compound. The gel composition may include one or more alkaloids.

The term "alkaloid compound" refers to any of a class of naturally occurring organic compounds that contain one or more basic nitrogen atoms. Typically, alkaloids contain at least one nitrogen atom in the amine-type structure. This or another nitrogen atom in the molecule of the alkaloid compound may be used as a base in an acid-base reaction. Most alkaloid compounds have one or more of the nitrogen atoms as part of a ring system, such as a heterocycle. In nature, alkaloid compounds are found primarily in plants, particularly in certain flowering plant families. However, some alkaloid compounds are present in animal species and fungi. In the present disclosure, the term "alkaloid compound" refers to alkaloid compounds of natural origin and synthetically produced alkaloid compounds.

The gel composition may preferably comprise an alkaloid compound selected from nicotine, anacitabine, and combinations thereof.

Preferably, the gel composition comprises nicotine.

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

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

Preferably, in embodiments in which the rod of aerosol-forming substrate comprises a gel composition, as described above, the downstream section of the aerosol-generating article comprises an aerosol-cooling element having a length of less than about 10 millimetres. It has been found that the use of a relatively short aerosol-cooling element in combination with a gel composition optimizes the delivery of the aerosol to the consumer.

Embodiments of the invention in which the rod of aerosol-forming substrate comprises a gel composition as described above, preferably comprise an upstream element (or upstream section) upstream of the rod of aerosol-forming substrate. In this case, the upstream element or segment advantageously prevents physical contact with the gel composition. The upstream element or segment may also advantageously compensate for any potential reduction in RTD, for example due to evaporation of the gel composition when the rod of aerosol-forming substrate is heated during use.

The sheet or web of homogenised tobacco material may comprise an aerosol former. As used herein, the term "aerosol-former" describes any suitable known compound or mixture of compounds that, in use, facilitates the formation of an aerosol and is substantially resistant to thermal degradation at the operating temperature of the aerosol-generating article.

Suitable aerosol-forming agents are known in the art and include, but are not limited to: polyhydric alcohols such as propylene glycol, triethylene glycol, 1, 3-butylene glycol, glycerin; esters of polyhydric alcohols, such as glycerol monoacetate, glycerol diacetate, or glycerol triacetate; and fatty acid esters of monocarboxylic, dicarboxylic 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 sheet or web of homogenised tobacco material may comprise a single aerosol former. Alternatively, the sheet or web of homogenized tobacco material may comprise a combination of two or more aerosol-formers.

The sheet or web of homogenized tobacco material has an aerosol former content of greater than 10% by dry weight. Preferably, the sheet or web of homogenized tobacco material has an aerosol former content of greater than 12% on a dry weight basis. More preferably, the sheet or web of homogenized tobacco material has an aerosol former content of greater than 14% by dry weight. Even preferably, the sheet or web of homogenized tobacco material has an aerosol former content of greater than 16% by dry weight.

The sheet of homogenized tobacco material may have an aerosol former content of about 10% to about 30% on a dry weight basis. Preferably, the sheet or web of homogenised tobacco material has an aerosol former content of less than 25% by dry weight.

In a preferred embodiment, the sheet of homogenised tobacco material has an aerosol former content of about 20% by dry weight.

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, for example the method disclosed in international patent application WO-A-2012/164009A 2. In a preferred embodiment, a sheet of homogenised tobacco material for use in an aerosol-generating article is formed from a slurry comprising particulate tobacco, guar gum, cellulosic fibres and glycerol by a casting process.

Alternative arrangements of homogenised tobacco material for use in rods in aerosol-generating articles will be known to the skilled person and may comprise a plurality of stacked sheets of homogenised tobacco material, a plurality of elongate tubular members formed by winding rods of homogenised tobacco material about a longitudinal axis thereof or the like.

As a further alternative, the rod of aerosol-forming substrate may comprise a non-tobacco based, nicotine-containing material, such as a sheet of sorbent non-tobacco material loaded with nicotine (e.g. in the form of a nicotine salt) and an aerosol-former. Examples of such rods are described in international application WO-A-2015/052652. Additionally or alternatively, the rod of the aerosol-forming substrate may comprise non-tobacco plant material, for example aromatic non-tobacco plant material.

The aerosol-forming substrate is surrounded by a wrapper. The packaging material may be formed from a porous or non-porous sheet material. The packaging material may be formed from any suitable material or combination of materials. Preferably, the packaging material is a paper packaging material.

The mouthpiece segment comprises a plug of filter material capable of removing a particulate component, a gaseous component, or a combination. Suitable filter materials are known in the art and include, but are not limited to: fibrous filter materials such as, for example, cellulose acetate tow, viscose, polyhydroxyalkanoate (PHA) fibers, polylactic acid (PLA) fibers, and paper; adsorbents such as, for example, activated alumina, zeolites, molecular sieves, and silica gel; and combinations thereof. In addition, the plug of filter material may further include one or more aerosol modifiers. Suitable aerosol modifiers are known in the art and include, but are not limited to, flavorants, such as, for example, menthol. In some embodiments, the mouthpiece segment may further comprise a mouth end recess downstream of the plug of filter material. For example, the mouthpiece segment may comprise a hollow tube longitudinally aligned with and arranged immediately downstream of the plug of filter material, the hollow tube forming a cavity at the mouth end, the cavity being open to the external environment at the downstream end of the mouthpiece segment and aerosol-generating article.

The length of the mouthpiece section is preferably at least about 4mm, more preferably at least about 6mm, even more preferably at least about 8 mm. Additionally or alternatively, the length of the mouthpiece section is preferably less than 25mm, more preferably less than 20mm, even more preferably less than 15 mm. In some preferred embodiments, the length of the mouthpiece segment is from about 4mm to about 25mm, more preferably from about 6mm to about 20 mm. The length of the mouthpiece section may be about 7 mm. The length of the mouthpiece section may be about 12 mm.

The length of the hollow tubular section is preferably at least about 10 mm. More preferably, the length of the hollow tubular section is at least about 15 millimeters. Additionally or alternatively, the length of the hollow tubular section is preferably less than about 30 millimeters. More preferably, the hollow tubular section has a length of less than about 25 millimeters. Even more preferably, the length of the hollow tubular section is less than about 20 millimeters. In some preferred embodiments, the hollow tubular section has a length of about 10mm to about 30mm, more preferably about 12mm to about 25mm, even more preferably about 15mm to about 20 mm. For example, in a particularly preferred embodiment, the length of the hollow tubular section is about 18 millimeters. In another particularly preferred embodiment, the length of the hollow tubular section is about 13 mm.

The length of the aerosol-cooling element is preferably at least about 10 mm. More preferably, the length of the aerosol-cooling element is at least about 15 millimetres. Additionally or alternatively, the length of the aerosol-cooling element is preferably less than about 30 millimetres. More preferably, the aerosol-cooling element has a length of less than about 25 mm. Even more preferably, the length of the aerosol-cooling element is less than about 20 mm. In some preferred embodiments, the aerosol-cooling element has a length of from about 10mm to about 30mm, more preferably from about 12mm to about 25mm, even more preferably from about 15mm to about 20 mm. For example, in a particularly preferred embodiment, the length of the aerosol-cooling element is about 18 millimeters. In another particularly preferred embodiment, the aerosol-cooling element has a length of about 13 mm.

The total length of the aerosol-generating article according to the invention is preferably at least about 40 mm. Additionally, or alternatively, the aerosol-generating article according to the present invention preferably has an overall length of less than about 70mm, more preferably less than 60 mm, even more preferably less than 50 mm. In a preferred embodiment, the aerosol-generating article has an overall length of between about 40mm and about 70 mm. In an exemplary embodiment, the total length of the aerosol-generating article is about 45 millimeters.

The support element (or support segment) may have a length of between about 5 millimeters and about 15 millimeters. In a preferred embodiment, the support element has a length of about 8 millimeters.

The aerosol-generating article preferably has an overall RTD of less than about 90 mm H2O (about 900 Pa). More preferably, the aerosol-generating article has an overall RTD of less than about 80 mm H2O (about 800 Pa). Even more preferably, the aerosol-generating article has a total RTD of less than about 70mm H2O (about 700 Pa).

In addition, or as an alternative, the aerosol-generating article preferably has a total RTD of at least about 30mm H2O (about 300 Pa). More preferably, the aerosol generating article has a total RTD of at least about 40mm H2O (about 400 Pa). Even more preferably, the aerosol-generating article has a total RTD of at least about 50mm H2O (about 500 Pa).

The RTD of the aerosol-generating article may be assessed as the negative pressure that must be applied to the downstream end of the mouthpiece under the test conditions defined in ISO 3402 in order to maintain a steady volumetric flow of air of 17.5ml/s through the mouthpiece. The RTD values listed above are intended to be measured on the aerosol-generating article alone (i.e. prior to insertion of the article into the aerosol-generating device) without blocking the perforations of the ventilation zone.

As used in this specification, the term "homogenised tobacco material" encompasses any tobacco material formed from the agglomeration of particles of tobacco material. A sheet or web of homogenised tobacco material is formed by agglomerating particulate tobacco obtained by grinding or otherwise powdering one or both of a tobacco lamina and a tobacco stem. In addition, the homogenized tobacco material may include small amounts of one or more of tobacco dust, tobacco fines, and other particulate tobacco by-products formed during processing, handling, and transport of the tobacco. The sheet of homogenised tobacco material may be produced by casting, extrusion, a paper making process or any other suitable process known in the art.

The support element may be formed from any suitable material or combination of materials. For example, the support element may be formed from one or more materials selected from the group consisting of: cellulose acetate, cardboard, crimped paper, such as crimped heat-resistant paper or crimped parchment, and polymeric materials, such as Low Density Polyethylene (LDPE). In a preferred embodiment, the support element is formed from cellulose acetate.

The aerosol-generating device may comprise an extractor for extracting an aerosol-generating article received in the aerosol-generating device, the extractor being configured to be movable within the device cavity.

The extractor may be configured to expose the airflow passage when the extractor is in an operating position, the operating position being defined by a heater in contact with an aerosol-forming substrate of an aerosol-generating article.

The extractor includes a container body configured to receive an aerosol-generating article. The container body (extractor body) of the extractor may include an end wall and a peripheral wall. The container body of the extractor includes an open end opposite the end wall through which the aerosol-generating article may be received. The aerosol-generating article is configured to abut the end wall once received within the extractor body. The peripheral wall of the container body may circumscribe the aerosol-generating article when the aerosol-generating article is received within the extractor. In such embodiments where an extractor is present, the peripheral wall of the extractor body may define an airflow channel. Alternatively, the peripheral wall of the device housing may define the airflow channel.

The extractor can be sized such that in the operating position, the container body extends between the first end of the airflow channel and the distal end of the device cavity. This enables the aerosol-generating article to be directly exposed to the airflow channel without the extractor body obstructing fluid communication between the airflow channel and the aerosol-generating article.

The extractor can be sized such that in the operative position, the container body extends between the mouth end of the device cavity and the distal end of the device cavity. In such embodiments, the extractor body may have a cut or a plurality of cuts to allow the airflow channel to be exposed to the aerosol-generating article when inserted. The extractor body and device cavity together may be configured to ensure alignment with the airflow passage or passages during use of the cutout or cutouts. For example, the suction body may comprise a protrusion arranged to mate with a slot or groove located in a housing of the aerosol-generating device.

The aerosol-generating device may comprise an elongate heater arranged for insertion into the aerosol-generating article when the aerosol-generating article is received within the device cavity. An elongated heater may be disposed with the device cavity. The elongated heater may extend into the device cavity. Alternative heating means are discussed further below. However, in such embodiments where the heater extends into the device cavity, the extractor body comprises an aperture at the end wall for allowing the heater to extend into the aerosol-generating article. Such apertures may allow air to enter the interior of the extractor cavity so that air may flow through the stem of the aerosol-forming substrate of the aerosol-generating article during use. Alternatively, additional apertures may be provided to allow air to enter the interior of the extractor chamber.

In some embodiments, the length of the extractor body can be less than the length of the device cavity. In such embodiments, the airflow channel may be defined by a portion of the device housing that does not enclose the peripheral wall of the extractor when the extractor is in the operating position (when the extractor abuts the distal end of the device cavity). This portion of the peripheral wall may define an airflow passage when the extractor is in the operating position. Indeed, the portion of the peripheral wall of the device housing may extend longitudinally past the extractor to define the airflow passage. The spacing or gap between the aerosol-generating article and the peripheral wall of the device housing defines an airflow channel.

In embodiments where an extractor is provided, the airflow passage may be defined between a peripheral wall of the aerosol-generating device housing and an outer surface of the extractor. Alternatively, the airflow channel may be defined within the extractor body. The air flow passage may be defined in a peripheral wall of the extractor body. The airflow passage may be defined within a thickness of a peripheral wall of the extractor body. The airflow channel may extend along the length of the extractor body. The air flow passage may extend from a longitudinal position away from the end wall of the extractor body to a longitudinal position near or at the open end of the extractor body.

In embodiments where no extractor is provided, the airflow passage may be defined within the thickness of a peripheral wall of the aerosol-generating device housing.

The heater may comprise an elongate heating element configured to penetrate a rod of the aerosol-forming substrate when the aerosol-generating article is received within the aerosol-generating device.

The heater may be any suitable type of heater. The heater may internally heat the aerosol-generating article. Alternatively, the heater may heat the aerosol-generating article externally. Such an external heater may surround the aerosol-generating article when inserted or received in the aerosol-generating device.

In some embodiments, the heater is arranged to heat an outer surface of the aerosol-forming substrate. In some embodiments, the heater is arranged to be inserted into the aerosol-forming substrate when the aerosol-forming substrate is received within the cavity. A heater may be positioned within the cavity. The heater may extend into the cavity. The heater may be an elongate heater. The elongate heater may be blade shaped. The elongated heater may be pin-shaped. The elongate heater may be tapered. In some embodiments, the aerosol-generating device comprises an elongate heater arranged for insertion into the aerosol-generating article when the aerosol-generating article is received within the cavity.

The heater may comprise at least one heating element. The at least one heating element may be any suitable type of heating element. In some embodiments, the device comprises only one heating element. In some embodiments, the device comprises a plurality of heating elements. The heater may comprise at least one resistive heating element. Preferably, the heater comprises a plurality of resistive heating elements. Preferably, the resistive heating elements are electrically connected in a parallel arrangement. Advantageously, providing a plurality of resistive heating elements electrically connected in a parallel arrangement may facilitate delivery of desired power to the heater while reducing or minimizing the voltage required to provide the desired power. Advantageously, reducing or minimizing the voltage required to operate the heater may facilitate reducing or minimizing the physical size of the power supply.

For forming at least oneSuitable materials for the resistive heating elements include, but are not limited to: semiconductors such as doped ceramics, electrically "conductive" ceramics (e.g., molybdenum disilicide), carbon, graphite, metals, metal alloys, and composites made of ceramic and metallic 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, nickel, cobalt, and iron,

And iron-manganese-aluminum based alloys.

In some embodiments, at least one resistive heating element comprises one or more stamped portions of resistive material (such as stainless steel). Alternatively, the at least one resistive heating element may comprise heating wires or filaments, such as Ni-Cr (nickel-chromium), platinum, tungsten or alloy wires.

In some embodiments, the at least one heating element comprises an electrically insulating substrate, wherein the at least one resistive heating element is disposed on the electrically insulating substrate.

The electrically insulating substrate may comprise any suitable material. For example, the electrically insulating substrate may comprise one or more of: paper, glass, ceramic, anodized metal, coated metal, and polyimide. The ceramic may include mica, alumina (Al 2O 3), or zirconia (ZrO 2). Preferably, the electrically insulating matrix has a thermal conductivity of less than or equal to about 40 watts/meter-kelvin, preferably less than or equal to about 20 watts/meter-kelvin, and ideally less than or equal to about 2 watts/meter-kelvin.

The heater may comprise a heating element comprising a rigid electrically insulating substrate having one or more electrically conductive tracks or wires disposed on a surface thereof. The electrically insulating substrate may be of a size and shape to allow it to be inserted directly into the aerosol-forming substrate. If the electrically insulating substrate is not sufficiently rigid, the heating element may comprise further stiffening means. An electrical current may be passed through one or more electrically conductive traces to heat the heating element and the aerosol-forming substrate.

In some embodiments, the heater comprises an induction heating device. The induction heating device may include an inductor coil and a power supply configured to supply a high-frequency oscillating current to the inductor coil. As used herein, the term "high frequency oscillating current" means an oscillating current with a frequency between 500kHz and 30 MHz. Advantageously, the heater may comprise a DC/AC inverter for converting DC current supplied by the DC power source into alternating current. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field upon receiving a high frequency oscillating current from a power supply. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field in the device cavity. In some embodiments, the inductor coil may substantially surround the device cavity. The inductor coil may extend at least partially along the length of the device lumen.

The heater may comprise an induction heating element. The induction heating element may be a susceptor element. As used herein, the term "susceptor element" refers to an element comprising a material capable of converting electromagnetic energy into heat. When the susceptor element is positioned in the alternating electromagnetic field, the susceptor is heated. The heating of the susceptor element may be the result of at least one of hysteresis losses and eddy currents induced in the susceptor, depending on the electrical and magnetic properties of the susceptor material.

The susceptor element may be arranged such that when the aerosol-generating article is received in the cavity of the aerosol-generating device, the oscillating electromagnetic field generated by the inductor coil induces an electric current in the susceptor element, causing the susceptor element to heat up. In these embodiments, the aerosol-generating device is preferably capable of generating a fluctuating electromagnetic field having a magnetic field strength (hfield strength) of between 1 and 5 kilo-amperes per meter (kA m), preferably between 2 and 3kA/m, for example about 2.5 kA/m. Preferably, the electrically operated aerosol-generating device is 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.

In some embodiments, the susceptor element is located in the aerosol-generating article. In these embodiments, the susceptor element is preferably positioned in contact with the aerosol-forming substrate. The susceptor element may be located in the aerosol-forming substrate.

In some embodiments, the susceptor element is located in the aerosol-generating device. In these embodiments, the susceptor element may be located in the cavity. The aerosol-generating device may comprise only one susceptor element. The aerosol-generating device may comprise a plurality of susceptor elements.

In some embodiments, the susceptor element is arranged to heat an outer surface of the aerosol-forming substrate. In some embodiments, the susceptor element is arranged to be inserted into the aerosol-forming substrate when the aerosol-forming substrate is received within the cavity.

The susceptor element may comprise any suitable material. The susceptor element may be formed from any material that is capable of being inductively heated to a temperature sufficient to release the volatile compounds from the aerosol-forming substrate. Suitable materials for the elongate susceptor element include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel-containing compounds, titanium, and composites of metallic materials. Some susceptor elements include metal or carbon. Advantageously, the susceptor element may comprise or consist of a ferromagnetic material, such as ferritic iron, a ferromagnetic alloy (e.g. ferromagnetic steel or stainless steel), ferromagnetic particles and ferrites. Suitable susceptor elements may be or include aluminum. The susceptor element preferably comprises greater than about 5%, preferably greater than about 20%, more preferably greater than about 50% or greater than about 90% ferromagnetic or paramagnetic material. Some of the elongated susceptor elements may be heated to a temperature in excess of about 250 degrees celsius.

The susceptor element may comprise a non-metallic core on which a metallic layer is provided. For example, the susceptor element may comprise metal traces formed on the outer surface of a ceramic core or substrate.

In some embodiments, the aerosol-generating device may comprise at least one resistive heating element and at least one inductive heating element. In some embodiments, the aerosol-generating device may comprise a combination of a resistive heating element and an inductive heating element.

The aerosol-generating device may comprise a power source. The power supply may be a DC power supply. In some embodiments, the power source is a battery. 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. However, in some embodiments, the power source may be another form of charge storage device, such as a capacitor. The power source may require recharging and may have a capacity that allows storage of energy sufficient for one or more user operations, e.g., one or more aerosol-generating experiences. For example, the power supply may have sufficient capacity to allow continuous heating of the aerosol-forming substrate for a period of approximately six minutes, corresponding to the typical time taken to smoke a conventional cigarette, or for a period of more than six minutes. In another example, the power source may have sufficient capacity to allow a predetermined number or discrete pumping or activation of the heater.

Drawings

Embodiments will now be described with reference to the drawings, in which:

figure 1 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention;

figure 2 is a schematic cross-sectional view of another embodiment of an aerosol-generating system according to the invention;

figure 3 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention;

figure 4 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention;

figure 5 is a schematic cross-sectional view of an aerosol-generating article for use in the aerosol-generating system shown in figures 3 and 4;

figure 6 is a schematic cross-sectional view of a comparative example of an aerosol-generating system;

figure 7 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention;

figure 8 is a schematic cross-sectional view of an aerosol-generating article for use in the aerosol-generating system of figure 7;

figure 9 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention;

figure 10 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention;

figure 11 is a schematic cross-sectional view of an aerosol-generating article according to the present invention for use in the aerosol-generating system of figures 9 and 10;

figure 12 is a schematic cross-sectional view of an embodiment of an aerosol-generating system according to the invention; and is provided with

Figure 13 is a schematic cross-sectional view of an aerosol-generating article for use in the aerosol-generating system of figure 12.

Detailed Description

Fig. 1 shows an aerosol-generating system 100 comprising an aerosol-generating device 10 and an aerosol-generating article 1. The aerosol-generating device 10 comprises a housing 4 extending between a mouth end 2 and a distal end (not shown). The housing 4 comprises a peripheral wall 6. The peripheral wall 6 defines a device cavity for receiving the aerosol-generating article 1. The device lumen is defined by a closed distal end and an open mouth end. The mouth end of the device cavity is located at the mouth end of the aerosol-generating device 10. The aerosol-generating article 1 is configured to be received through the mouth end of the device cavity and is configured to abut the closed end of the device cavity.

The air flow passage 5 is defined within a peripheral wall 6. The air flow passage 5 extends between an inlet 7 at the mouth end of the aerosol-generating device 10 and an outlet 9 at a distal position along the peripheral wall 6.

The aerosol-generating device 10 further comprises a heater (not shown) and a power supply (not shown) for supplying power to the heater. A controller (not shown) is also provided to control this supply of power to the heater. The heater is configured to heat the aerosol-generating article 1 during use when the aerosol-generating article 1 is received within the device 10.

The aerosol-generating article 1 comprises a first air entry region 15 located along the wrapper 22. As shown in fig. 1, the first air entry region 15 comprises a perforation line extending through the packaging material 22. The outlet 9 is configured to align with or cover the first air entry region 15 when the aerosol-generating article 1 is received within the device cavity. Once received within the device cavity, the upstream end of the aerosol-generating article 1 is arranged to abut the closed end of the device cavity such that air drawn through the aerosol-generating device 10 does not flow past the upstream end of the aerosol-generating article 1. As shown in fig. 1, air drawn through the aerosol-generating device 10 can only enter the aerosol-generating article 1 through the first air entry region 15.

As shown in figure 1, the aerosol-generating article 1 and the device cavity are arranged to form an airtight fit such that air cannot flow between the peripheral wall 6 and the article 1. This airtight fit is established along a substantial portion of the entire length of the device lumen. The device lumen has a length of about 25 mm.

As an alternative to defining an airtight fit over the entire length between the device cavity and the aerosol-generating article 1, the aerosol-generating system 200 may comprise an aerosol-generating device 20 having a circumferential protrusion 29 extending from the peripheral wall 6 into the device cavity, as shown in figure 2. The circumferential projection 29 is configured to establish an air-tight fit with a portion of the aerosol-generating article 1 at a location downstream of the first air entry region 15 when received within the aerosol-generating device. The inner diameter of the circumferential projection 29 is arranged to be similar to the diameter of the aerosol-generating article 1 so as to define an airtight fit. This ensures that air drawn through the aerosol-generating device 20 can only enter the aerosol-generating article 1 via the air flow channel 5 and its outlet 7, and cannot pass through the gap between the article 1 and the device cavity.

Figure 3 is a more detailed illustration of the aerosol-generating system 100 similar to that shown in figure 1. The air flow passage 5 is defined within a peripheral wall 6. The airflow channel 5 comprises a first portion extending in an axial direction from an inlet 7 and a second portion extending in a transverse or radial direction from an end of the first portion to an outlet 9. Thus, the air flow channel 5 comprises an L-shaped bend.

Figure 4 shows an aerosol-generating system 300 similar to that shown in figure 3. The aerosol-generating system 300 comprises an aerosol-generating device 30 and an aerosol-generating article 1. The aerosol-generating device 30 is similar to the aerosol-generating device 10, but differs in that an airflow channel 205 is defined along the inner surface of the peripheral wall 6. In such embodiments, a portion of the airflow channel 205 is configured to cover the first air entry region 15 of the aerosol-generating article 1. The airflow channel 205 has a length of about 23 millimeters. The entire length of the air flow channel 205 is configured to cover the aerosol-generating article 1 when received within the device 30.

Fig. 5 shows an aerosol-generating article 1 configured for use with the aerosol-generating

systems

100, 200, 300 shown in fig. 1 to 4.

The aerosol-generating article 1 comprises a rod 12 of aerosol-forming substrate, a hollow support segment 14, an aerosol-cooling element (or segment) 16 and a mouthpiece segment 18. The components downstream of the rod 12 of aerosol-forming substrate (in this case, the hollow support segment 14, the aerosol-cooling element 16 and the mouthpiece segment 18) form a downstream section of the aerosol-generating article 1. These four elements are arranged in end-to-end, longitudinally aligned fashion and are surrounded by a wrapper 22 to form the aerosol-generating article 1. The aerosol-generating article 1 shown in figure 1 is particularly suitable for use with an electrically operated aerosol-generating device 1 comprising a heater for heating a rod 12 of an aerosol-forming substrate.

The rod 12 of aerosol-forming substrate has a length of about 12mm and a diameter of about 7 mm. The rod 12 is cylindrical and has a substantially circular cross-section. The rod 12 comprises a sheet of gathered homogenised tobacco material. The hollow cellulose acetate tube (hollow support section) 14 has a length of about 8mm and a thickness of its peripheral wall of about 1mm.

The mouthpiece section 18 comprises a core rod of cellulose acetate tow of 8 denier per filament and has a length of about 7 millimeters. The mouthpiece section 18 has a diameter of about 7 mm. The aerosol-cooling element 16 has a length of about 18mm and a diameter of about 7 mm.

The aerosol-generating article 1 comprises a first air entry region 15 disposed along the rod of aerosol-forming substrate at least about 2mm from the upstream end of the rod 12 of aerosol-forming substrate. The first air entry region 15 is located less than about 10mm from the downstream end of the rod 12 or upstream end of the hollow support section 14 of the aerosol-forming substrate. The first air entry region 15 surrounds the aerosol-generating article 1. That is, the first air entry region 15 surrounds the entire periphery of the aerosol-generating article 1.

Fig. 6 shows a comparative example of an incompatible aerosol-generating article 102 for use with the aerosol-generating device 30 shown in fig. 4, which incompatible aerosol-generating article does not have a first air entry region located along and around the rod of aerosol-forming substrate. Due to the fact that the article 102 has no air entry zone, and the upstream end of the article 102 abuts the distal end of the device cavity, air cannot be drawn through the device and article 102.

Figure 7 shows an aerosol-generating system 400 similar to the aerosol-generating system 300 shown in figure 4. The aerosol-generating system 400 comprises an aerosol-generating device 40 and an aerosol-generating article 103. The aerosol-generating system 400 differs from the aerosol-generating system 300 in that the first air entry region 115 is located around the hollow support section 14 of the aerosol-generating article 103, as shown in figure 8. Assuming that the rod 12 of aerosol-forming substrate and the hollow support section 14 are directly adjacent, the first air entry region 115 is located about 2mm downstream of the upstream end of the hollow support section 14 and about 2mm downstream of the downstream end of the rod 12 of aerosol-forming substrate.

Due to the position of the first air entry region 115, the air flow channel 305 defined in the peripheral wall 6 of the aerosol-generating device 40 is shorter than the air flow channel 5. The length of the airflow channel 305 is between about 11mm and about 13 mm.

Fig. 9 shows an aerosol-generating system 500 similar to the aerosol-generating system 100. The aerosol-generating system 500 comprises an aerosol-generating device 50 and an aerosol-generating article 104, both configured for use with one another. The aerosol-generating device 50 is similar to the aerosol-generating device 10, but differs in that the device 50 comprises an airflow channel 405 comprising one inlet 7 and two

outlets

9, 19. The first outlet 9 of the airflow channel 405 is configured to provide fluid communication between the exterior of the aerosol-generating device 50 and the first air entry region 15 of the aerosol-generating article 104. The second outlet 19 of the airflow channel 405 is configured to provide fluid communication between the exterior of the aerosol-generating device 50 and the second air entry region 115 of the aerosol-generating article 104.

Fig. 10 shows an aerosol-generating system 600 similar to the aerosol-generating system 500. Rather, the aerosol-generating system 600 comprises the aerosol-generating device 30 and the aerosol-generating article 104. As described above, the airflow passage 205 is defined along the inner surface of the peripheral wall 6.

An aerosol-generating article 104 is shown in figure 11. The two

air entry regions

15, 115 are located along and around two different components of the aerosol-generating article 104. The first air entry zone 15 is arranged along the rod 12 of aerosol-forming substrate at least about 2mm downstream of the upstream end of the rod 12 of aerosol-forming substrate. The second air entry region 115 is arranged at least about 2mm downstream of the rod 12 of aerosol-forming substrate along the hollow support section 14 and at least about 2mm downstream of the upstream end of the hollow support section 14.

As shown in both fig. 9 and 10, fluid communication between the exterior of the aerosol-generating

device

30, 40 and the interior of the aerosol-generating article 104 is established via two different

air entry regions

15, 115. The first air entry region 15 is configured to allow more air to pass through than the second air entry region 115. In other words, the first air entry zone 15 is configured to provide a greater level of air entry than the second air entry zone 115.

When the article 104 is received within the

device

30, 40, the first air entry region 15 is configured as the primary air entry region for the aerosol-generating article 104 when the upstream end of the article 104 is in abutment with the distal end of the device cavity. The second air entry zone 115 is configured to provide ventilation to the article 104; that is, air is caused to flow from the rod 12 of aerosol-forming substrate to the aerosol through the hollow support section 14 towards the mouth end of the article 104. Second air entry region 115 includes a perforation line extending around packaging material 22 and extending through packaging material 22 and the peripheral wall of hollow support segment 14.

Fig. 12 shows an aerosol-generating system 700 comprising an aerosol-generating device 30 and an aerosol-generating article 105, as shown in fig. 13. The aerosol-generating article 105 comprises two

air entry regions

215, 315 separated by a distance of about 1.5 mm. The first air entry region 215 includes a porous portion of the wrapper 22. Such porous portions forming the first air entry region 15 are about 3mm wide. The second air entry region 315 includes a perforation line extending through and around the packaging material 22. The second air entry zone 315 is located about 1.5mm downstream of the first air entry zone 215. Both the first air entry region 215 and the second air entry region 315 are located along the rod 12 of aerosol-forming substrate. The first air entry region 215 is located about 2mm downstream of the upstream end of the rod 12 of aerosol-forming substrate.

When received within the aerosol-generating device 30, the open upstream end of the aerosol-generating article 105 abuts the distal end of the device cavity so as to prevent air from flowing past the upstream end of the aerosol-generating article 105. Thus, during use, air is configured to flow through the first air entry zone 215 due to the overlap between the airflow channel 205 and the first air entry zone 215.

Each of the aerosol-generating

devices

10, 20, 50 discussed above comprises more than one airflow channel. The aerosol-generating

device

10, 20, 50 shown in fig. 1,2,3, 6 and 9 comprises at least two

elongate airflow channels

5, 405. As shown in fig. 4, 7, 10 and 12, each of the aerosol-generating

devices

30, 40 comprises an

annular airflow channel

205, 305.

Unless otherwise stated, each of the described aerosol-generating

articles

1, 102, 103, 104, 105 comprises the same structural components, for example, the rod 12 of aerosol-forming substrate, the hollow support segment 14, the aerosol-cooling element 16 and the mouthpiece segment 18 arranged within the wrapper 22 — but the main difference is in the configuration of the air entry region provided on the article.

Claims

1. An aerosol-generating system comprising:

an aerosol-generating article comprising:

a rod of aerosol-forming substrate; and

a filter positioned downstream of the rod of aerosol-forming substrate;

wherein the rod of aerosol-forming substrate and the filter are assembled within a wrapper, the aerosol-generating article comprising a first air entry region on the wrapper configured to allow air to enter the interior of the aerosol-generating article;

an aerosol-generating device having a distal end and a mouth end, the aerosol-generating device comprising:

a housing defining a device cavity for removably receiving the aerosol-generating article at the mouth end of the device;

a heater for heating the aerosol-forming substrate when the aerosol-generating article is received within the device cavity; and

an air flow channel extending between a channel inlet and a channel outlet, the air flow channel being configured to establish fluid communication between an interior of the device cavity and an exterior of the aerosol-generating device;

wherein the aerosol-generating system is configured such that, when the aerosol-generating article is received within the device cavity, fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device is established by fluid communication established between the first air entry region of the aerosol-generating article received within the device cavity and the air flow channel of the aerosol-generating device;

further wherein the aerosol-generating device comprises a peripheral wall defining the device cavity, and wherein a sealing portion of the peripheral wall is configured to establish an airtight fit with a portion of the aerosol-generating article at a location downstream or upstream of the first air entry region of the aerosol-generating article when the aerosol-generating article is received within the aerosol-generating device.

2. An aerosol-generating system according to claim 1, wherein fluid communication between the interior of the aerosol-generating article and the exterior of the aerosol-generating device is established by an airflow channel outlet of the aerosol-generating device covering the first air entry region of the aerosol-generating article received within the device cavity.

3. An aerosol-generating system according to claim 1 or 2, wherein the upstream end of the aerosol-generating article is blocked when the aerosol-generating article is received within the device cavity, thereby substantially preventing air from entering the aerosol-generating article through the upstream end of the aerosol-generating article.

4. An aerosol-generating system according to any preceding claim, wherein the diameter of the device cavity increases from the sealing portion of the peripheral wall in a direction towards the distal end of the device cavity.

5. An aerosol-generating system according to any preceding claim, wherein the aerosol-generating device comprises a peripheral wall defining the device cavity, and wherein the aerosol-generating device comprises a circumferential protrusion extending from the peripheral wall into the device cavity, the circumferential protrusion being configured to establish an airtight fit with a portion of the aerosol-generating article at a location downstream of the first air entry region of the aerosol-generating article when received within the aerosol-generating device.

6. An aerosol-generating system according to any preceding claim, wherein the wrapper of the aerosol-generating article comprises a gas-impermeable material.

7. An aerosol-generating system according to any preceding claim, wherein the first air entry region is located along a rod of the aerosol-forming substrate.

8. An aerosol-generating system according to any preceding claim, wherein the first air entry zone is located at least 2mm downstream of the upstream end of a rod of the aerosol-forming substrate.

9. An aerosol-generating system according to any preceding claim, wherein the filter of the aerosol-generating article comprises:

a mouthpiece segment comprising a plug of filter material arranged downstream of the rod of aerosol-forming substrate; and

a hollow tubular section located between the mouthpiece section and the rod of aerosol-forming substrate.

10. An aerosol-generating system according to claim 9, wherein the first air entry region is located along the hollow tubular section.

11. An aerosol-generating system according to any preceding claim, wherein the aerosol-generating article comprises a second air entry zone located on the wrapper at a position downstream of the first air entry zone.

12. An aerosol-generating system according to claim 11, wherein the second air entry region is located at a position at least 1mm downstream of the rod of aerosol-forming substrate.

13. An aerosol-generating system according to claim 11 or 12, wherein the level of air ingress into the interior of the aerosol-generating article through the first air entry region is configured to be greater than the level of air ingress into the interior of the aerosol-generating article through the second air entry region.

14. An aerosol-generating system according to any preceding claim, wherein the air entry region comprises a plurality of apertures extending through the packaging material.