An Aerosol Generating Article

Abstract

An aerosol generating article for use with an aerosol generating device comprises a substantially planar aerosol generating substrate, at least one airflow channel extending along the substantially planar aerosol generating substrate (14), and a wrapping member surrounding the substantially planar aerosol generating substrate and the at least one airflow channel. The at least one airflow channel comprises two or more portions having different cross-sections.

Description

TECHNICAL FIELD

The present disclosure relates generally to aerosol generating articles, and more particularly to an aerosol generating article for use with an aerosol generating device for heating the aerosol generating article to generate an aerosol for inhalation by a user. The present disclosure is particularly applicable to aerosol generating articles for use with a portable (hand-held) aerosol generating device.

TECHNICAL BACKGROUND

The popularity and use of reduced-risk or modified-risk devices (also known as aerosol generating devices or vapour generating devices) has grown rapidly in recent years as an alternative to the use of traditional tobacco products. Various devices and systems are available that heat or warm aerosol generating substances to generate an aerosol for inhalation by a user.

A commonly available reduced-risk or modified-risk device is the heated substrate aerosol generating device, or so-called heat-not-burn device. Devices of this type generate an aerosol or vapour by heating an aerosol generating substrate to a temperature typically in the range 150° C. to 300° C. Heating the aerosol generating substrate to a temperature within this range, without burning or combusting the aerosol generating substrate, generates a vapour which typically cools and condenses to form an aerosol for inhalation by a user of the device.

Currently available aerosol generating devices can use one of a number of different approaches to provide heat to the aerosol generating substrate, including resistive heating which makes use of a resistive heating element and induction heating which makes use of an induction coil and an inductively heatable susceptor.

Whichever approach is used to heat the aerosol generating substrate, the characteristics of the aerosol generated by the aerosol generating device are dependent upon a number of factors, including the construction of the aerosol generating article used with the aerosol generating device. There is, therefore, a desire to provide an aerosol generating article which enables the characteristics of the aerosol generated during use of the article to be optimised, and which at the same time is easy to use in combination with an aerosol generating device.

SUMMARY OF THE DISCLOSURE

According to a first aspect of the present disclosure, there is provided an aerosol generating article for use with an aerosol generating device, the aerosol generating article comprising:

• • a substantially planar aerosol generating substrate;
  • at least one airflow channel extending along the substantially planar aerosol generating substrate; and
  • a wrapping member surrounding the substantially planar aerosol generating substrate and the at least one airflow channel;
  • wherein the at least one airflow channel comprises two or more portions having different cross-sections.

The aerosol generating article is for use with an aerosol generating device for heating the aerosol generating substrate, without burning the aerosol generating substrate, to volatise at least one component of the aerosol generating substrate and thereby generate a heated vapour which cools and condenses to form an aerosol for inhalation by a user of the aerosol generating device. The aerosol generating device is a hand-held, portable, device.

In general terms, a vapour is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapour can be condensed to a liquid by increasing its pressure without reducing the temperature, whereas an aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas. It should, however, be noted that the terms ‘aerosol’ and ‘vapour’ may be used interchangeably in this specification, particularly with regard to the form of the inhalable medium that is generated for inhalation by a user.

By providing the at least one airflow channel with two or more portions having different cross-sections, an improved delivery of vapour and/or aerosol may be achieved. In addition, by surrounding the at least one airflow channel with the wrapping member, vapour and/or aerosol generated during use of the aerosol generating article in an aerosol generating device flows internally within the article, along the at least one airflow channel, before it is inhaled by a user. The formation of condensed matter on the internal surfaces of the aerosol generating device is thereby substantially eliminated, or at least minimised, and this may provide a number of benefits. For example, it may help to reduce residue build-up within the aerosol generating device, and reduce the number of cleaning and maintenance operations that a user of the device must perform. It may also help to ensure that the greatest possible quantity of vapour and/or aerosol is delivered to the user, and that the delivered vapour and/or aerosol has optimal characteristics.

The at least one airflow channel may comprise two or more portions having different cross-sectional shapes. Alternatively or in addition, the at least one airflow channel may comprise two or more portions having different cross-sectional areas. This may facilitate vapour generation and the efficient delivery of the vapour and/or aerosol to the user for inhalation.

The aerosol generating article may include a distal end, a mouth end and a longitudinal axis which may extend between the mouth end and the distal end. The mouth end is located at an opposite end of the aerosol generating article to the distal end. More particularly, the mouth end is located downstream of the distal end with respect to an airflow direction through the aerosol generating article, e.g., during use of the aerosol generating article in an aerosol generating device. The at least one airflow channel may extend in a first direction which may be substantially parallel to the longitudinal axis. Air flows along the at least one airflow channel, from the distal end to the mouth end, during use of the aerosol generating article thereby ensuring that a maximum amount of volatile components are released into the air from the heated aerosol generating substrate as the air flows along the airflow channel. This in turn ensures that the greatest possible quantity of vapour and/or aerosol is generated and delivered to the user during use of the aerosol generating article.

The two or more portions of the at least one airflow channel may comprise an upstream portion and a downstream portion. The upstream portion and the downstream portion correspond to the airflow direction through the aerosol generating article. In other words, the upstream portion is positioned at the distal end of the aerosol generating article and the downstream portion is positioned at the mouth end of the aerosol generating article, i.e., the downstream portion is positioned downstream of the upstream portion with respect to an airflow direction through the aerosol generating article, e.g., during use of the aerosol generating article in an aerosol generating device. The downstream portion may have a larger cross-sectional area than the upstream portion. This arrangement may facilitate the generation of vapour, and may facilitate cooling and condensing of the generated vapour to form an aerosol with suitable characteristics for inhalation by a user.

The upstream portion of the at least one airflow channel may comprise a groove which may be formed in a surface of the substantially planar aerosol generating substrate. The downstream portion of the at least one airflow channel may comprise a slit which may be formed on one end of the substantially planar aerosol generating substrate.

The substantially planar aerosol generating substrate may have a flat rectangular shape which may have a pair of main surfaces. The wrapping member may comprise a pair of rectangular sheets which may be attached, respectively, to the pair of main surfaces. The aerosol generating article may have a pleasing aesthetic appearance due to the flat rectangular shape of the aerosol generating substrate. The aerosol generating substrate may be readily covered by the wrapping member, thereby ensuring that a user does not directly touch the aerosol generating substrate during handling of the aerosol generating article. The flat rectangular shape may also facilitate packaging and storage of multiple aerosol generating articles.

The aerosol generating article may comprise a support member which may form a mouth-end portion of the article. The support member may have a tubular form, e.g., a rectangular tubular form, to receive a downstream end of the aerosol generating substrate and the at least one airflow channel, for example the portion of the at least one airflow channel having a larger cross-sectional area. The support member may be self-supporting and may, for example, comprise cardboard or a plastics material. The support member may advantageously deliver vapour and/or aerosol generated during use of the article directly to a user's mouth. The support member may allow heated vapour generated during use of the aerosol generating article to cool and condense to form an aerosol with optimal characteristics for inhalation by a user.

The wrapping member may comprise a material which is substantially non-electrically conductive and non-magnetically permeable and may, for example, comprise a paper wrapper. The use of a paper wrapper may facilitate manufacture and handing of the aerosol generating article and may enhance aerosol generation.

The wrapping member may have a porous inner surface which may face towards the aerosol generating substrate for absorbing condensation. The porous inner surface may further help to ensure that the formation of condensed matter on the internal surfaces of the aerosol generating device is substantially eliminated, or at least minimised. The wrapping member may have an anti-stick outer surface which may face away from the aerosol generating substrate. For example, the wrapping member may comprise an anti-stick coating on the outer surface. The anti-stick outer surface may help to ensure that the wrapping member does not stick to surfaces of the aerosol generating device when it has been heated. Together, the porous inner surface and the anti-stick outer surface may help to reduce residue build-up within the aerosol generating device, thus reducing the number of cleaning and maintenance operations that a user of the device may have to perform.

The aerosol generating substrate may comprise a non-liquid aerosol generating material, for example any type of solid or semi-solid material. Example types of aerosol generating solids include powder, granules, pellets, shreds, strands, particles, gel, strips, loose leaves, cut leaves, cut filler, porous material, foam material or sheets. The aerosol generating substrate may comprise plant derived material and in particular, may comprise a tobacco. It may advantageously comprise reconstituted tobacco, for example including tobacco and any one or more of cellulose fibres, tobacco stalk fibres and inorganic fillers such as CaCO3.

Consequently, the aerosol generating device with which the aerosol generating articles are intended for use may be referred to as a “heated tobacco device”, a “heat-not-burn tobacco device”, a “device for vaporising tobacco products”, and the like, with this being interpreted as a device suitable for achieving these effects. The features disclosed herein are equally applicable to devices which are designed to vaporise any aerosol generating substrate.

The aerosol generating substrate may comprise an aerosol-former. Examples of aerosol-formers include polyhydric alcohols and mixtures thereof such as glycerine or propylene glycol. Typically, the aerosol generating substrate may comprise an aerosol-former content of between approximately 5% and approximately 50% on a dry weight basis. In some embodiments, the aerosol generating substrate may comprise an aerosol-former content of between approximately 10% and approximately 20% on a dry weight basis, and possibly approximately 15% on a dry weight basis.

The aerosol generating article may be configured for use with an electrically-operated aerosol generating device including a heater. The heater may be a resistive heater or may be an inductive heater. Upon heating, the aerosol generating substrate may release volatile compounds. The volatile compounds may include nicotine or flavour compounds such as tobacco flavouring.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic longitudinal cross-sectional view of a first example of an aerosol generating article;

FIG. 2 is a diagrammatic cross-sectional view along the line A-A in FIG. 1;

FIG. 3 is a diagrammatic cross-sectional view along the line B-B in FIG. 1;

FIG. 4 is a diagrammatic longitudinal cross-sectional view of a second example of an aerosol generating article; and

FIG. 5 is a diagrammatic cross-sectional view of an aerosol generating system comprising an aerosol generating device and an aerosol generating article according to the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

Referring initially to FIGS. 1 to 3, there is shown a first example of an aerosol generating article 1 for use with an electrically-operated aerosol generating device 102, an example of which will be described later in this specification with reference to FIG. 5. The aerosol generating article 1 is substantially planar and has a distal end 10 and a mouth end 12 (or proximal end) at the opposite end of the aerosol generating article 1. The mouth end 12 is downstream of the distal end 10 with respect to an airflow direction through the aerosol generating article 1 as represented in FIG. 1 by the three arrows. A longitudinal axis extends between the distal end 10 and the mouth end 12 to define a longitudinal direction of the aerosol generating article 1.

The aerosol generating article 1 comprises a substantially planar aerosol generating substrate 14. The aerosol generating substrate 14 comprises a bulk or mass of aerosol generating material and has a flat rectangular shape with a pair of oppositely disposed main surfaces 14a, 14b. The aerosol generating article 1 is a consumable, or disposable, article in which the aerosol generating substrate 14 may comprise tobacco or a tobacco material.

The aerosol generating article 1 comprises a plurality of airflow channels 16 which, in the illustrated example, comprise a plurality of grooves 18 formed in a main surface 14a of the aerosol generating substrate 14. The grooves 18 are arranged side-by-side and parallel to each other, and the grooves 18 extend in the longitudinal direction between the distal end 10 and the mouth end 12, substantially parallel to the longitudinal axis. Together, the grooves 18 form a fluted surface 20. The grooves 18 may be formed in any suitable manner, for example by pressing the main surface 14a of the aerosol generating substrate 14 with a suitably shaped pressing tool. Three grooves 18 are shown in the example of FIGS. 1 and 2, but it will be understood that any suitable number of grooves 18 can be provided, for example depending on the desired resistance-to-draw of the aerosol generating article 1. It should also be noted that the grooves 18 may have any suitable cross-sectional shape including, but not limited to, rectangular as illustrated in FIGS. 2 and 3, square, trapezoidal, or semi-circular.

Each airflow channel 16 comprises a first portion 16a and a second portion 16b having different cross-sections. In the example illustrated in FIGS. 1 to 3, the second portion 16b is positioned downstream of the first portion 16a. The first portion 16a (or upstream portion) has a first cross-sectional area and the second portion 16b (or downstream portion) has a second cross-sectional area which is larger than the first cross-sectional area. The first portion 16a of each airflow channel 16 comprises a first groove portion 18a formed in the main surface 14a of the aerosol generating substrate 14. The second portion 16b of each airflow channel 16 comprises a second groove portion 18b formed in the main surface 14a of the aerosol generating substrate 14. The second groove portion 18b is wider and deeper than the first groove portion 18a, resulting in the larger second cross-sectional area described above. The second groove portion 18b (i.e., the second portion 16b of each airflow channel 16) terminates in a slit 19 formed on one end 30 of the aerosol generating substrate 14.

The aerosol generating article 1 further comprises a wrapping member 22 which surrounds the aerosol generating substrate 14 and the grooves 18 that form the airflow channels 16. The aerosol generating substrate 14 and the grooves 18 are, thus, fully enclosed by the wrapping member 22 which may, for example, comprise cigarette paper or a similar material. The wrapping member 22 comprises a pair of rectangular sheets 24, 26 which are attached, respectively, to the main surfaces 14a, 14b of the aerosol generating substrate 14. The rectangular sheets 24, 26 are typically formed by a single sheet of material which is wrapped around the aerosol generating substrate 14 and which may have overlapping edges that are adhered to each other to secure the wrapping member 22 in position around the aerosol generating substrate 14 and the grooves 18.

In an exemplary and non-limiting example, the aerosol generating substrate 14 may have a length (in the longitudinal direction of the aerosol generating article 1) of approximately 18.0 mm, may have a width of approximately 11.8 mm, and may have a thickness (or depth) of approximately 1.2 mm. The aerosol generating substrate 14 may be spaced inwardly from the distal end 10 of the aerosol generating article 1 by a small distance, for example approximately 3.0 mm, as shown in FIG. 1. The aerosol generating article 1 may have a width of approximately 12.0 mm and a thickness (or depth) of approximately 1.4 mm to accommodate the aerosol generating substrate 14 inside the wrapping member 22. The aerosol generating article 1 may have any suitable length between the distal end 10 and the mouth end 12 by varying the length of the portion of the wrapping member 22 that extends between the downstream end of the aerosol generating substrate 14 and the mouth end 12. As vapour flows through this portion of the wrapping member 22 during use of the aerosol generating article 1 in an aerosol generating device 102, the vapour may cool and condense to form an aerosol for inhalation by a user. Thus, the length of the portion of the wrapping member 22 that extends between the downstream end of the aerosol generating substrate 14 and the mouth end 12 of the aerosol generating article 1 may be selected at the time of manufacture to provide an aerosol with desired characteristics.

In some embodiments, the wrapping member 22 comprises a porous inner surface 22a which faces towards the aerosol generating substrate 14 and which is capable of absorbing condensation that may be formed during the heating process. Alternatively or in addition, the wrapping member 22 can comprise an anti-stick outer surface 22b facing away from the aerosol generating substrate 14 to reduce the risk of the wrapping member 22 sticking to surfaces of the aerosol generating device 102 when it has been heated. The anti-stick outer surface 22b may comprise an anti-stick coating on the outer surface 22b of the wrapping member 22.

Referring now to FIG. 4, there is shown a second example of an aerosol generating article 2. The aerosol generating article 2 is similar to the aerosol generating article 1 described above with reference to FIGS. 1 to 3 and corresponding features are identified using the same reference numerals.

The aerosol generating article 2 includes a support member 28 positioned at the mouth end 12 of the aerosol generating article 2 to form a mouth-end portion 34 which can be engaged by a user's lips during use of the aerosol generating article 2 in an aerosol generating device 102. The support member 28 typically comprises a self-supporting material such as cardboard or a plastics material and has a rectangular tubular form when viewed in cross-section to receive a downstream end of the aerosol generating substrate 14 and the grooves 18 formed in the surface 14a. The wrapping member 22 also surrounds the support member 28.

Referring now to FIG. 5, there is shown an aerosol generating system 100 comprising an aerosol generating device 102 and a first example of an aerosol generating article 1 as described above with reference to FIGS. 1 to 3. It will be appreciated that the aerosol generating device 102 could be used in combination with an alternative aerosol generating article according to the present disclosure, such as the second example of the aerosol generating article 2 described above with reference to FIG. 4.

The aerosol generating device 102 comprises a receiving chamber 106 and a heater 104 positioned in the device body 108 to provide heat to the receiving chamber 106. The heater 104 may be a resistive heater or may alternatively be an induction heater comprising a susceptor and an electromagnetic field generator including an induction coil.

In use, a user inserts the aerosol generating article 1 into the receiving chamber 106. The aerosol generating device 102 may include a cover 110 and a pivotal mounting 112 that allows the cover 110 to be moved between a closed position shown in FIG. 5 and an open position (not shown). As will be understood by one of ordinary skill in the art, a user must pivot the cover 110 to the open position to permit insertion of the aerosol generating article 1 into the receiving chamber 106 and then pivot the cover back to the closed position shown in FIG. 5 to retain the aerosol generating article 1 in position in the receiving chamber 106.

The aerosol generating device 102 includes a power source 114, e.g., a rechargeable battery, and a controller 116, both of which are connected to the heater 104. The heater 104 may be actuated manually, e.g., via a user interface such as a button on the aerosol generating device 102, or may be actuated automatically in response to a user drawing on a mouthpiece 118 of the aerosol generating device 102. The aerosol generating device 102 includes one or more air inlets 120 to allow air to flow into the aerosol generating article 1 and through the grooves 18 formed in the surface of the aerosol generating substrate 14. The airflow direction is illustrated by the arrows in FIG. 5.

With the aerosol generating article 1 positioned in the receiving chamber 106, power is supplied from the power source 114 to the heater 104 (either by a manual or automatic actuation of the heater 104 as described above), thereby heating the aerosol generating substrate 14 without burning it to release one or more volatile components. The volatile components are entrained in the air flowing through the grooves 18 thereby forming a vapour. The vapour cools and condenses as it flows through the grooves 18 to form an aerosol which is inhaled by a user through the mouthpiece 118 of the aerosol generating device 102.

When the aerosol generating substrate 14 becomes depleted and no longer releases sufficient volatile components to generate an aerosol with acceptable qualities, the aerosol generating article 1 can be removed from the receiving chamber 106 after pivoting the cover 110 to the open position, and a replacement aerosol generating article 1 can be inserted in its place.

In the event that the aerosol generating device 102 is used in combination with an aerosol generating article having a support member 28, for example the second example of the aerosol generating article 2 described above with reference to FIG. 4, the support member 28 may project from an open end 106a of the receiving chamber 106 thereby enabling a user's lips to engage the mouth-end portion 34 of the aerosol generating article 3 formed by the support member 28.

Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications may be made to those embodiments without departing from the scope of the appended claims. Thus, the breadth and scope of the claims should not be limited to the above-described exemplary embodiments.

Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

Claims

1. An aerosol generating article for use with an aerosol generating device, the aerosol generating article comprising:

a substantially planar aerosol generating substrate;

at least one airflow channel extending along the substantially planar aerosol generating substrate; and

a wrapping member surrounding the substantially planar aerosol generating substrate and the at least one airflow channel;

wherein the at least one airflow channel comprises two or more portions having different cross-sections.

2. The aerosol generating article according to claim 1, wherein the aerosol generating article includes a distal end, a mouth end, a longitudinal axis extending between the mouth end and the distal end, and the at least one airflow channel extends in a first direction substantially parallel to the longitudinal axis.

3. The aerosol generating article according to claim 1, wherein the two or more portions comprise an upstream portion and a downstream portion, the downstream portion having a larger cross-sectional area than the upstream portion.

4. The aerosol generating article according to claim 1, wherein the two or more portions comprise an upstream portion and a downstream portion, the upstream portion of the at least one airflow channel comprises a groove formed in a surface of the substantially planar aerosol generating substrate and the downstream portion of the at least one airflow channel comprises a slit formed on one end of the substantially planar aerosol generating substrate.

5. The aerosol generating article according to claim 1, wherein the substantially planar aerosol generating substrate has a flat rectangular shape having a pair of main surfaces and the wrapping member comprises a pair of rectangular sheets attached, respectively, to the pair of main surfaces.

6. The aerosol generating article according to claim 1, wherein the aerosol generating article comprises a support member forming a mouth-end portion of the article, and the support member has a tubular shape to receive a downstream end of the aerosol generating substrate and the at least one airflow channel.

7. The aerosol generating article according to claim 1, wherein the wrapping member has a porous inner surface facing towards the aerosol generating substrate for absorbing condensation and an anti-stick outer surface facing away from the aerosol generating substrate.

8. The aerosol generating article according to claim 7, wherein the wrapping member comprises an anti-stick coating on the outer surface.