GB2590345A

GB2590345A - Component

Info

Publication number: GB2590345A
Application number: GB1914342.9A
Authority: GB
Inventors: Berry Charles; Rushforth David
Original assignee: Nicoventures Trading Ltd
Current assignee: Nicoventures Trading Ltd
Priority date: 2019-10-04
Filing date: 2019-10-04
Publication date: 2021-06-30
Also published as: GB201914342D0

Abstract

A component for an aerosol provision system comprises: a liquid container for an aerosol forming liquid; a wick and heater for drawing liquid from the liquid container and volatilising said liquid; and a capsule for an aerosol precursor material, the capsule configured to release the aerosol precursor material for volatilisation in response to an increase in temperature of the heater caused by exhaustion of the aerosol forming liquid. The capsule may be partially or completely formed from a material which ruptures, degrades or melt in response to the temperature increase, such as microcrystalline wax and/or glass, or from a material which shrinks and thereby ruptures in response to the temperature increase, such as a plastic material. The capsule may be configured to release the material at a temperature less than the degradation temperature of the wick and/or less than the degradation temperature of the aerosol precursor material, i.e. from about 250°C to about 300°C. The capsule may contain a flavoured liquid, or be formed from a flavoured solid or amorphous solid, wherein said flavour is different to a flavour of the aerosol forming liquid. The aerosol forming liquid may contain nicotine.

Description

COMPONENT

FIELD

The present disclosure relates to a component for an aerosol provision system which has a heater and a wick, and to electronic aerosol provision systems such as electronic cigarettes or the like, incorporating such components.

BACKGROUND

Electronic aerosol provision systems such as electronic cigarettes (e-cigarettes) generally contain a reservoir of liquid which is to be vaporised. When a user inhales on the device, a heater is activated to vaporise a small amount of liquid, which is therefore inhaled by the user. The liquid to be vaporised in e-cigarettes is typically a solution containing nicotine and often a flavourant or flavouring agent. The solvent may be, for example, glycerol.

The vaporising part of the device is often designed for multiple uses, although single use devices do exist. In multiple and single use devices, a container holding the aerosol-forming solution is present. Typically this container is found in a cartomiser/cartridge, and devices can comprise a modular assembly with reusable and replaceable cartomisers; the cartomiser will comprise the consumable aerosol precursor material (e.g. aerosol-forming solution) and a vaporiser, while a reusable device part will comprise longer-life items, such as a battery, device control circuitry, activation sensors and user interface features. The reusable device part may be referred to as a control unit or battery section.

The cartomiser may be electrically and mechanically coupled to the control unit for use, for example, using a screw thread or bayonet fixing with appropriately engaging electrical contacts. When the aerosol precursor material is exhausted, or the user wishes to switch to a different solution, the cartomiser may be removed from the control unit and a replacement attached in its place. Alternatively the removed cartomiser may be refilled before reattachment to the control unit.

An aerosol provision system may be configured to issue user notifications, for example, an aerosol provision system may comprise a controller configured to monitor an operating state of the system, and to determine when a particular operating condition arises and provide a user notification in response thereto. An aerosol provision system may be configured to provide a user with a warning when a remaining amount of power or charge in a battery or a remaining amount of aerosol precursor material in a container falls below a threshold level.

These kinds of user notifications are often provided using an indicator light, such as a light emitting diode, mounted on the device.

SUMMARY

In one aspect there is provided a component for an aerosol provision system, the component comprising: a liquid container for containing an aerosol forming liquid; a wick arranged to draw liquid from the liquid container in use; and a heater arranged to volatilise liquid drawn from the liquid container by the wick in use, to generate an aerosol in use; and a capsule for an aerosol precursor material. The capsule is configured to release the aerosol precursor material for volatilisation in response to an increase in temperature of the heater caused by exhaustion of the aerosol forming liquid.

In another aspect, there is provided an aerosol provision system comprising a component as defined herein, and a power supply comprising a cell or battery for supplying power to the component.

In a further aspect, there is provided a method of providing an aerosol for inhalation by a user. The method comprises: volatilising, by a heater, aerosol forming liquid drawn in from a liquid container by a wick, thereby generating an aerosol; and on exhaustion of the aerosol forming liquid, allowing an increase in temperature of the heater such that a capsule releases an aerosol precursor material for volatilisation and inhalation by the user, thereby indicating the exhaustion of the aerosol forming liquid.

In a further aspect, there is provided a use of a capsule for an aerosol precursor material to provide an end-of-life flavour to a user of an aerosol provision system.

These and further aspects are set out in the appended independent and dependent claims. It will be appreciated that features of the dependent claims may be combined with each other and with features of the independent claims in combinations other than those explicitly set out in the claims. Furthermore, the approaches described herein are not restricted to specific embodiments such as those set out below, but include and contemplate any appropriate combinations of features presented herein. For example, a component may be provided in accordance with approaches described herein which includes any one or more of the various features described below as appropriate.

DETAILED DESCRIPTION

Aspects and features of certain examples and embodiments are discussed and described herein. Some aspects and features of certain examples and embodiments may be implemented conventionally and these are not discussed or described in detail in the interests of brevity. It will thus be appreciated that aspects and features of apparatus and methods discussed herein which are not described in detail may be implemented in accordance with any conventional techniques for implementing such aspects and features.

As described above, the present disclosure relates to a component which may be used in an aerosol provision system. More specifically, the present disclosure provides a component for an aerosol provision system such as an e-cigarette, which is able to provide different aerosols or vapours in a controlled and pre-determined manner. Such aerosols may have different flavours, and may be able to indicate to a user that the container for aerosol forming liquid is nearly empty or exhausted, e.g. via an "end-of-life" flavour. This is advantageous because it can avoid a user having an unsatisfactory sensory experience upon exhaustion of the aerosol forming liquid.

In arriving at the present disclosure, it was recognised that the known approaches for providing user notifications in aerosol provision systems can have some drawbacks. For example, the provision of an indicator light can increase manufacturing complexity and associated costs, and requires visual attention from users. In addition, known approaches for providing user notification of a cartridge needing replacement can often be accompanied by an unpleasant or undesirable flavour due to the liquid reaching a critical level in the reservoir. Accordingly there is a desire for alternative schemes for providing user notifications in aerosol provision systems, and specifically a desire for systems to be able to provide an "end-of-life" or "exhaustion" notification to a user without relying on visual attention from users.

Finally, there is a desire for alternative schemes for providing multiple flavours to a user. Known approaches for delivering multiple flavours include having multiple flavour-containing reservoirs in a cartridge, optionally with user control of the end flavour which is inhaled. Such approaches are, however, complex in terms of manufacture and require user involvement in order to deliver a particular flavour profile.

As well as providing an exhaustion indication without requiring user attention or involvement, the present disclosure describes a component for an aerosol provision system which can be easily implemented by a user to provide a boost or burst of flavour or other sensory experience (e.g. aroma or the like). For ease of reference, these and further aspects of the present disclosure are now discussed.

The present disclosure relates to a component for an aerosol provision system. The component includes a liquid container, a wick, a heater and a capsule. The component may be held within an aerosol provision system (e.g. an e-cigarette) or may be sold as a separate entity for subsequent use with or in such a system.

As understood by one skilled in the art, aerosol provision systems such as e-cigarettes typically contain a unit known as a cartomiser which comprises a reservoir of solution, a wick and a heating element for volatilising the solution to generate an aerosol. In one aspect the component is therefore a cartomiser or is part of a cartomiser. Typically a cartomiser has a housing, e.g. formed of a plastics material, which supports other components of the cartomiser and also provides a mechanical interface for connecting the cartomiser with a control unit of an aerosol provision system as required. The manner by which the cartomiser connects to the control unit is not significant for the present disclosure. It may, for example, comprise a screw thread fitting or any other attachment or connection means known to the person skilled in the art.

The shape of the component described herein is not limited and may be any shape known in the art. In various embodiments of the present disclosure, the component is annular in shape. Other suitable shapes would be known in the art and include e.g. spherical, tubular, irregular spherical and capsule shaped. The liquid container may further comprise the majority of the interior volume of the component. In various embodiments, the liquid container may generally conform to the shape of the component, e.g. it may be annular or at least partially annular in shape. The liquid container is for containing an aerosol forming liquid; it may be referred to herein as a reservoir and may be formed in accordance with conventional techniques, for example comprising a moulded plastics material.

In various embodiments of the present disclosure, the liquid container contains an aerosol forming liquid and this liquid is volatilised by the heater due to the action of the wick in use.

As is common in the technical field, the terms "vapour" and "aerosol", and related terms such as "vaporise", "volatilise" and "aerosolise", may be used interchangeably herein.

The aerosol forming liquid contained in the liquid container is a liquid that is capable of generating aerosol when heated. In general, the aerosol forming liquid includes a solvent and at least one flavourant or flavouring agent. In various embodiments of the present disclosure, the aerosol forming liquid further comprises an active agent, e.g. nicotine. The aerosol forming liquid is discussed further below along with the aerosol precursor material of the capsule.

As described herein, the component includes a heater and a wick. The wick is arranged to draw liquid from the liquid container in use and the heater is arranged to volatilise this liquid to generate an aerosol in use. In various embodiments, the wick and the heater may be arranged in a space within the component that defines an aerosol generation chamber. Any heater/wick combination known in the art may be used; the present disclosure is not limited in this respect. The heater and wick may therefore be a combined element and/or may be integrally formed with one another. Alternatively the heater and wick may be separate elements.

In various embodiments of the present disclosure, the wick may extend transversely across an aerosol generation chamber with its ends extending into the liquid container, through openings in the inner wall of the container. The openings in the inner wall of the container may be sized to broadly match the dimensions of the wick to provide a reasonable seal against leakage from the liquid container into the air path without unduly compressing the wick, which may be detrimental to its fluid transfer performance. Aerosol forming liquid contained in the liquid container may infiltrate the wick through surface tension or capillary action.

In other embodiments of the present disclosure the wick and heater may be provided by a porous ceramic heater. For example, the component may comprise a porous ceramic disc such that the liquid within the container may seep through the ceramic disc and come into the vicinity of a heating element for volatilisation to generate an aerosol.

In various embodiments, the liquid container substantially surrounds the wick along a length of the wick.

The terms "heater" and "heating element" are used interchangeably herein. The heater may comprise an electrically resistive wire coiled around the wick so that electrical power may be supplied to the heater to volatise an amount of the aerosol forming liquid drawn into the vicinity of the heater by the wick. The heater may comprise a nickel chrome alloy wire and the wick may comprise a glass fibre bundle, but it will be appreciated that the specific heater/wick configuration is not significant to the present disclosure.

In arriving at the present disclosure, it was surprisingly found that the exhaustion of a liquid container in an aerosol provision system can be monitored without user involvement through the use of a capsule for an aerosol precursor material. It is generally known in the art that in normal use of an e-cigarette -i.e. with an adequate level of liquid in the reservoir -an equilibrium is established between the energy supplied to the heater and the energy supplied to the aerosol forming liquid in order to vaporise the liquid. This equilibrium means that the liquid effectively has a "cooling" or regulating effect on the heater. The energy supplied to the heater is used to vaporise or volatilise the liquid rather than to raise the temperature of the heater per se (i.e. the liquid reaches its latent heat of vaporisation).

However, when the aerosol forming liquid is depleted in the container and the wick cannot be replenished as normal, the liquid can no longer provide the cooling effect on the heater and the temperature of the heater increases. The increase in temperature of the heater is often referred as "burn-out" or "dry-out" conditions. Dry-out conditions are not desirable because they can damage the wick and heater, and also result in the user inhaling an unpleasant aerosol.

The "capsule-in-wick" concept disclosed herein is a means for addressing the "burn-out" or "dry-out" issue and notifying the user that they need to replenish the liquid in the reservoir. "Burn-out" or "dry-out" can be avoided because the aerosol precursor material released by the capsule and/or the capsule itself can have a cooling effect on the heater and reverse any increase in temperature caused by exhaustion of the liquid. In addition, the manufacturer can include either a different flavour or sensorial compound which tells the user that the aerosol-forming liquid is exhausted. Accordingly the present disclosure provides a user notification mechanism by configuring the capsule to release the aerosol precursor material in response to an increase in temperature of the heater caused by exhaustion of the aerosol forming liquid.

In order to avoid release of the aerosol precursor material from the capsule before exhaustion of the aerosol forming liquid, the capsule should retain its structure in the normal operating temperature of the device. Wien the aerosol provision system is an e-cigarette or the like, this operating temperature is typically between about 180 and 240°C. In various embodiments, the capsule is therefore configured to release the aerosol precursor material for volatilisation at a temperature of no less than about 250°C, e.g. about 250 to 300°C. In this way, the release of material from the capsule is triggered by the increase in temperature of the heater caused by exhaustion of the aerosol forming liquid and not by the normal operating temperature of the device.

Alternatively, the capsule may be configured to release the aerosol precursor material for volatilisation at a temperature which is greater than the volatilisation temperature of the aerosol forming liquid and less than the degradation temperature of the wick. For example, if the aerosol forming liquid vaporises or volatilises at e.g. 180°C and the wick degrades/burns at e.g. 250°C, the capsule can in this instance, be configured to release the aerosol precursor material at any temperature between > 180°C and < 250°C. A low difference between the volatilisation temperature of the aerosol forming liquid and capsule release means that there is a more rapid response to a dry-out detection, whereas a higher difference can reduce the chances of early release.

As the skilled person will appreciate operating temperatures of devices and degradation temperatures of wicks and materials vary, but the exact temperature at which the capsule releases the aerosol precursor material is not significant, it is the trigger and subsequent release which is important in the context of the present disclosure. As noted above, the inventors believe that the material released from the capsule may act to cool the heater and thereby prevent the heater from overheating while generating aerosol indicative of a dry-out or end-of-life condition.

Accordingly in various embodiments of the present disclosure, the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is at least about 2°C greater than the maximum temperature at which the heater volatilises the liquid drawn from the liquid container by the wick in use, for example, from 2 to 20°C greater than the maximum temperature at which the heater volatilises the liquid drawn from the liquid container by the wick in use. The maximum temperature at which the heater volatilises the liquid may also be referred to herein as the volatilisation temperature of the liquid. The temperature at which the capsule releases the aerosol precursor material may also be less than the degradation temperature of the wick and/or less than the degradation temperature of the aerosol precursor material.

In various embodiments, the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is at least about 2°C greater than the volatilisation temperature of the liquid, and less than the degradation temperature of the wick. In various embodiments, the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is at least about 2°C greater than the volatilisation temperature of the liquid, and less than the degradation temperature of the aerosol precursor material. In various embodiments, the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is at least about 2°C greater than the volatilisation temperature of the liquid, and less than the degradation temperature of the wick and the degradation temperature of the aerosol precursor material.

For example, if the heater operates in a temperature range of 200 to 230°C, with the liquid volatilising at 230°C, the capsule can be configured to release the aerosol precursor material at a temperature of at least 232°C. In this way, the release is triggered by the exhaustion of aerosol forming liquid and increase in heater temperature. In addition if the wick burns or otherwise degrades at 250°C, the upper limit for capsule release is less than 250°C.

In various embodiments, the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is up to 10°C higher than the volatilisation temperature of the liquid. This temperature range is not, however, limiting because as explained above, it is not the specific temperature at which the liquid is released, but rather the trigger of the liquid. In addition, various embodiments involve the temperature at which the capsule releases the liquid to be less than the degradation temperature of the wick and/or liquid.

The mechanism by which the capsule releases the aerosol precursor material is not limited and may be any mechanism known in the art, including rupture, melting, thermal degradation, thermally activated release, shrinking, expansion or a combination thereof. In various embodiments of the present disclosure, the capsule therefore contains an aerosol precursor material, e.g. by being in the form of a substrate, a shell, a matrix or the like, and the substrate, shell or matrix material is that which ruptures, degrades, melts etc. to release the aerosol precursor material for volatilisation.

Alternatively the capsule may be at least partially formed of an aerosol precursor material, e.g. the capsule is formed of an aerosol precursor solid or a gel, and it is this precursor material which ruptures, degrades, melts etc. on the increase in heater temperature to thereby generate a liquid for the wick to draw to the heater for volatilisation. In some embodiments, the aerosol precursor material may comprise an "amorphous solid", which may alternatively be referred to as a "monolithic solid" (i.e. non-fibrous). In some embodiments, the amorphous solid may be a dried gel. The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the aerosolisable material may for example comprise from about 50wV/0, 60wt% or 70wt% of amorphous solid, to about 90wt%, 95wt% or 100wt% of amorphous solid.

In various embodiments of the present disclosure, the capsule is partially or completely formed from a material which melts or thermally degrades in response to the increase in temperature of the heater in the component. The capsule may, for example, be partially or completely formed from a material which melts or thermally degrades at the above-mentioned temperatures, i.e. at a temperature of no less than 250°C (e.g. 250 to 300 or 250 to 280°C) or at a temperature which is at least 2°C greater than the volatilisation temperature of the aerosol forming liquid, or at a temperature which is up to 10°C higher than the volatilisation temperature of the liquid. In addition, the temperature of melting or degradation of the capsule material may be less than the degradation temperature of the wick and/or liquid. Such material may comprise, consist essentially or consist of the aerosol precursor material, or the material may be different from the aerosol precursor material, e.g. a substrate, shell or matrix material as mentioned above.

When a substrate, shell or matrix material is used for the capsule, said material should typically not have a significant effect on the flavour characteristic of the aerosol precursor material contained in or by the capsule. In contrast, when the capsule is partially or completely formed by an aerosol precursor material, this aerosol precursor material may have a second flavour characteristic as defined below. Although only two flavour characteristics are discussed herein, the person skilled in the art will appreciate that the invention is not limited in this respect. The capsule may, for example, be formed partially or completely from an aerosol precursor material with a second flavour characteristic and further contain an aerosol precursor material with a third flavour characteristic. The third flavour characteristic may be the same or different from the second and/or first flavour characteristic.

The person skilled in the art will readily be able to identify materials that meet the above functional definitions in terms of melting and thermally degradation, because melting temperature or the temperature at which a material thermally degrades is readily determined using routine techniques including differential scanning calorimetry (DSC). Melting point/temperature is also a property which is regularly reported by a manufacturer of a commercially available material.

In the present disclosure, melting point is preferably determined as follows: a quantity of the substance is heated slowly, while stirring, until it reaches a temperature of 90C° or higher to completely melt the substance; - the source of heat is moved, and the melted (molten) substance allowed to cool to a temperature of 8 to 10°C above the expected melting point; the bulb of an ASTM 14C (American Society for Testing and Materials) or equal thermometer is chilled to 5°C, wiped dry and whilst still cold, immersed into the molten substance so that approximately the lower half of the bulb is submerged; - the bulb is withdrawn immediately, and held vertically away from the heat until the wax surface dulls, then dipped for 5 min into a water bath having a temperature not higher than 16°C; the thermometer is fixed securely in a test tube so that the lower point is 15 mm above the bottom of the test tube, and the test tube suspended in a water bath adjusted to about 16°C; the temperature of the bath is raised at the rate of 2°C per min to 30°C, then changed to a rate of 1°C per min and the temperature at which the first drop of melted substance leaves the thermometer is noted.

This method is carried out twice on a freshly melted portion of the substance. If the variation of three determinations is less than 1°C, the mean average of the three is the melting point. If the variation of the three determinations is greater than 1°C, make two additional determinations and take the average of the five.

The capsule material that melts or thermally degrades to release the aerosol precursor material may generally be a solid at room temperature and at the operating temperature of the device (including the temperature at which the aerosol forming liquid volatises), but undergo a phase change/degradation at the temperature reached by the heater on exhaustion of the aerosol forming liquid, so as to provide a further aerosol precursor material (e.g. liquid) for volatilisation and inhalation by the user.

In various embodiments of the present disclosure, the material that melts or thermally degrades in response to the increase in temperature of the heater may be selected from the group consisting of waxes, polyethers, polysaccharides, gums, fats, cellulose gums, and thermoplastic polymers, or a mixture thereof In various embodiments, the material is selected from the group consisting of carbohydrates, carbohydrate derivatives, fats, waxes, polyvinyl pyrrolidone, polyvinyl alcohol and chitosan. Examples of suitable materials include a microcrystalline wax, a polyethylene glycol, carboxymethyl cellulose, pullulan, polyvinyl pyrrolidone, polyvinyl alcohol, sodium alginate, shea butter, levan, chitosan or a mixture thereof.

The skilled person will appreciate that mixtures of materials may also be used in order to arrive at a material which will melt or thermally degrade in response to the increase in temperature of the heater. Materials such as hydroxypropylmethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, xanthan gum, tragacanth gum, guar gum, acacia gum, Arabic gum, natural waxes, carbowax, carboxyvinyl polymer, high amylose starch, hydroxypropylated high amylose starch, dextrin, pectin, and chitin may for example, be combined to form mixtures with the desired properties.

In various embodiments of the present disclosure, the material that melts or thermally degrades in response to the increase in temperature of the heater may be selected from the group consisting of a microcrystalline wax, a polyethylene glycol, gums or a mixture thereof, e.g. a mixture of a microcrystalline wax such as 180F or CMP601, both available from HCI Wax, and a gum.

Microcrystalline waxes are a type of wax produced by de-oiling petroleum and can be classified as "laminating" or "hardening" grades. For the purposes of the present disclosure, the microcrystalline wax may be of a hardening grade.

Polyethylene glycols are polyethers often referred to as "PEG". They are commercially available over a wide range of molecular weights, and are typically named with a number that describes their average molecular weight. PEG 400 would, for example, be a polyethylene glycol having an average molecular weight of approximately 400 Daltons. Commercially available PEGs with suitable melting points are well-known to the person skilled in the art and would be readily identifiable for the reasons already presented above.

In various embodiments of the present disclosure, the capsule is partially or completed formed from a material which ruptures in response to the increase in temperature of the heater. Rupture may occur by any mechanism known in the art and generally refers to a change in the capsule's physical or chemical structure such that the aerosol precursor material contained in or by the capsule is released. The capsule material may, for example, chemically or physically degrade, break or crack due to expansion/shrinkage, shatter or otherwise rupture. The degree of rupture is also not limited; all that is required is for the capsule to rupture by enough to release the aerosol precursor material for volatilisation by the heater.

In various embodiments of the present disclosure, the capsule is partially or completely formed from a material which ruptures at the above-mentioned temperatures, i.e. at a temperature of no less than 250°C (e.g. 250 to 300 or 250 to 280°C) or at a temperature which is at least 2°C (e.g. at least 5°C) greater than the volatilisation temperature of the aerosol forming liquid, and less than the degradation temperature of the wick and/or the degradation temperature of the precursor material in the capsule as discussed above.

Alternatively the capsule is partially or completely formed from a material which ruptures at a temperature which is up to 10°C higher than the volatilisation temperature of the liquid, and less than the degradation temperature of the wick and/or precursor material in the capsule.

The person skilled in the art will readily be able to identify materials that meet such a functional definition. Such material may comprise, consist essentially or consist of the aerosol precursor material, or the material may be different from the aerosol precursor material, e.g. a substrate, shell or matrix material as mentioned above.

When a substrate, shell or matrix material is used for the capsule, this material should typically not have a significant effect on the flavour characteristic of the aerosol precursor material contained in or by the capsule. Alternatively when the capsule is partially or completely formed by an aerosol precursor material, this aerosol precursor material may have a second flavour characteristic as defined below. As noted above, a third flavour characteristic may also be present.

The material that ruptures in accordance with the present disclosure may be a material that ruptures by shattering such as a glass. By the term "glass" is meant a solid that has a noncrystalline (amorphous) structure at the atomic scale, and that exhibits a glass transition when heated towards the liquid state. Ceramic materials, silicon-based materials and many thermoplastic polymers are glass materials. Suitable glass materials may have a glass transition temperature of no less than 250°C (e.g. 250 to 300 or 250 to 280°C) or a glass transition temperature which is at least 2°C (e.g. at least 5°C) greater than the volatilisation temperature of the liquid or up to 10°C higher than the volatilisation temperature of the liquid. As discussed above, the upper limit for the latter ranges may be the degradation temperature of the wick and/or the degradation temperature of the aerosol precursor material in the capsule (which ever is the lowest). The person skilled in the art will readily be able to identify materials that meet this definition; for example, using routine techniques such as DSC or from information on commercially available materials.

In various embodiments, the material forming the capsule may rupture due to shrinkage. Put another way, the capsule may be partially or completely formed from a material which shrinks and thereby ruptures in response to the increase in temperature of the heater. Materials that have such shrink behaviour at high temperatures may be plastic materials, e.g. plastics that have a shrink temperature of no less than about 250°C (e.g. 250 to 300 or 250 to 280°C) or plastics that have a shrink temperature which is at least 2°C (e.g. at least 5°C) greater than the volatilisation temperature of the liquid or up to 10°C higher than the volatilisation temperature of the liquid. As discussed above, the upper limit for the latter ranges may be the degradation temperature of the wick and/or the degradation temperature of the aerosol precursor material in the capsule (which ever is the lowest).

The plastics that meet the requirements of the present disclosure may be thermoplastics. In various embodiments of the present disclosure, the plastic is a thermoplastic that is known in the art for the purposes of shrink-wrap. Such thermoplastics may include polypropylene (e.g. bi-orientated polypropylene), cellophane, polyethylene (e.g. low density polyethylene), polyether ether ketone, or a mixture thereof.

In various embodiments, the material forming the capsule may be a material (e.g. a substrate or matrix material) that can absorb and then subsequently release the aerosol precursor material on application of heat. For example, the capsule may be formed of a substrate or matrix material which is a plastic film with pores or micro-holes, a sponge-like film, a porous carbon material, a porous ceramic material, or a fibrous element. Possible materials include cellulose acetate, polyurethane, vinyl acetate, polycarbonate, carbon, ceramics, silicon compounds or mixtures thereof.

The location of the capsule is not limited, provided that it is able to release the aerosol precursor material on an increase in temperature of the heater caused by exhaustion of the aerosol forming liquid. The capsule may, for example, be located in the liquid container. In various embodiments, however, the capsule is in the vicinity of the wick, including being present in the wick. Such a location allows the capsule to provide a rapid release of the aerosol precursor material and address the burn-out or dry-out issues discussed herein.

The aerosol precursor material contained in or used for the capsule is a material which is capable of generating aerosol when heated. In general, the aerosol precursor material may be in the form of a solid, liquid or gel which may or may not contain nicotine and/or flavourants. In some embodiments, the aerosol precursor material may comprise an "amorphous solid", which may alternatively be referred to as a "monolithic solid" (i.e. non-fibrous). In some embodiments, the amorphous solid may be a dried gel. The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the aerosolisable material may for example comprise from about 50wt%, 60wW0 or 70wtcY0 of amorphous solid, to about 90wW0, 95wt% or 100wt% of amorphous solid.

In various embodiments of the present disclosure, the capsule contains an aerosol precursor material that is a flavoured liquid. Alternatively the capsule may be formed from a flavoured gel or solid. When the liquid container contains a flavoured aerosol forming liquid, it is preferable for the flavours to be different. The aerosol forming liquid in the container may have a first flavour characteristic and the aerosol precursor material contained in or of the capsule may have a second flavour characteristic, where the second flavour characteristic is different from the first flavour characteristic. In accordance with the disclosure presented herein, the flavour characteristics may be used to notify the user that the container in the aerosol provision system has reached its "end-of-life" or is exhausted; an "end-of-life" or "exhaustion" flavour arising from volatilisation of the aerosol precursor material released from the capsule.

In various embodiments of the present disclosure, the aerosol forming liquid in the container has a flavour characteristic for normal use and the aerosol precursor material released from the capsule has a different flavour characteristic. The relative amounts of the aerosol forming liquid and capsule-based aerosol precursor material can also be adjusted so that the user knows how many puffs they have left before the container is completely depleted, i.e. once the material in the capsule is exhausted.

In various embodiments of the present disclosure, the capsule contains an aerosol precursor material and this material is included in an amount which equates to about 10 to about 20 puffs of an aerosol provision system. On sensing the flavour characteristic of the aerosol precursor material, the user knows that they have about 10 about 20 puffs before the container must be replaced or refilled. Depending on the size of the container, the skilled person will be able to calculate the appropriate amount of the aerosol precursor material to deliver about 10 to about 20 puffs. For example, if the container is approximately 2 ml in size and delivers approximately 166 puffs in total, the aerosol precursor material will be included in the capsule at an amount of approximately 0.24 ml to deliver 20 puffs to the user.

The flavour characteristics of the aerosol forming liquid in the container and the aerosol precursor material of the capsule are not limited and can be achieved by any suitable means known in the art. In various embodiments of the present disclosure, these flavour characteristics can be achieved by including or equally not-including a "flavour", "flavouring agent" or "flavourant". The terms "flavour, "flavouring agent" and "flavourant" are used interchangeably to refer to materials which, where local regulations permit, are added to the formulation to create a desired taste or aroma in a product for adult consumers. Reference here to "flavour", "flavouring agent" or "flavourant" include both singular and multi-component flavours.

It will be appreciated that the specific nature of the flavours used in accordance with the present disclosure is not necessarily significant. For example, in various embodiments both flavour characteristics are provided by the same flavour but at different strengths/levels/concentrations. What is significant is that a characteristic of the flavour associated with the aerosol changes. Thus a change in flavour characteristic may comprise, for example, a change in actual flavour, a change in strength of a flavour, or a change in whether there is any flavour.

In various embodiments of the present disclosure, the aerosol forming liquid in the container is flavoured and the aerosol precursor material in the capsule is not flavoured. Alternatively, the aerosol forming liquid in the container is flavoured and the aerosol precursor material in the capsule is also flavoured, or the aerosol forming liquid in the container is not flavoured and the aerosol precursor material in the capsule is flavoured. In various embodiments, the aerosol precursor material in the capsule includes a tobacco flavour. In other embodiments the aerosol precursor material includes a non-tobacco flavour.

When a flavour, flavouring agent or flavourant is used to provide a flavour characteristic, this flavour, flavouring agent or flavourant may be selected from the group consisting of extracts, for example liquorice, hydrangea, Japanese white bark magnolia leaf, tobacco, chamomile, fenugreek, clove, menthol, Japanese mint, aniseed, cinnamon, herb, wintergreen, cherry, berry, peach, apple, Drambuie, bourbon, scotch, whiskey, spearmint, peppermint, lavender, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, honey essence, rose oil, vanilla, lemon oil, orange oil, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, pimento, ginger, anise, coriander, coffee, flavour enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and/or sugar substitutes (e.g. sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They may be imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, oil, liquid, or powder.

In various embodiments the capsule includes an aerosol precursor material with a flavour characteristic that indicates to a user that the container is nearing the end of its life. This indicative flavour could be e.g. menthol, such that when the user inhales vapour with a menthol flavour, they know to replace the container with a fresh container.

In other embodiments the capsule includes an aerosol precursor material with a flavour which extends the life of the aerosol provision system as well as providing an indication to a user that the container is nearing the end of it life. This flavour could be e.g. a tobacco flavour. The use of a tobacco flavour is particularly advantageous for a hybrid device comprising a container of the present disclosure and a substrate which is tobacco.

When used in a hybrid device, the first flavour characteristic of the aerosol forming liquid may be for normal use and the liquid may be included in the container in an amount which corresponds to the number of puffs associated with the life of the substrate. For example, if the substrate is a tobacco material and included in an amount of which corresponds to approximately 160 puffs in normal use, the aerosol forming liquid can be included in an amount also corresponding to approximately 160 puffs in normal use. This means that when substantially all of the aerosol forming liquid has been drawn to the heater by the wick and volatilised, and the heater temperature increased due to exhaustion of the aerosol forming liquid, the release and volatilisation of the aerosol precursor material with the second flavour characteristic will substantially coincide with the exhaustion of the tobacco material. The second flavour characteristic can then either be a flavour which, when sensed by the user, indicates that the substrate and container need replacing and/or a tobacco flavour to avoid the loss of flavour on exhaustion of the substrate.

Alternatively the second flavour characteristic can be used to provide additional flavours to a user, not necessarily associated with a user notification.

Thus, in accordance with various embodiments, a component and an aerosol provision system are provided which generate end-of-life feedback for a user without relying on control circuitry or multiple containers/cartomisers. Not only does this obviate the need for a separate status light indicator or complex device design/manufacture, but it can provide the user with notification without the user needing to maintain visual focus on a light indicator.

This can help provide the user with end-of-life notifications in situations where an illuminating light would not be desired.

As noted above, the aerosol forming liquid includes a solvent. The solvent is not limited and may be any material typically used in liquids for e-cigarettes, i.e. a material that volatilises on application of heat. The solvent may be selected from the group consisting of water, propylene glycol, glycerol, 1,3-propanediol and mixtures thereof.

In various embodiments, the aerosol forming liquid is an aqueous solution. For example, the aerosol forming liquid may comprise water and one or more compounds selected from propylene glycol, glycerol, 1,3-propanediol and mixtures thereof. In various embodiments the aqueous solution comprises water and at least one of propylene glycol and glycerol. In various embodiments the aqueous solution comprises water, propylene glycol and glycerol.

When the aerosol precursor material contained in or by the capsule is a liquid, gel or amorphous solid, it may include a solvent defined in the same manner as the aerosol forming liquid. In other words, the aerosol precursor material may be a liquid, gel or amorphous solid comprising a solvent and one or more flavourants or flavouring agents. In various embodiments, the aerosol precursor material is a liquid comprising a solvent and one or more flavourants or flavouring agents.

As an alternative or in addition to the different flavour characteristics discussed above, the aerosol forming liquid and aerosol precursor material may be distinguished by the solvent used and consequently the level of aerosol produced therefrom. For example, the aerosol precursor material may include a higher level of glycerol, propylene glycol, 1,3-propanediol, or a mixture thereof compared to the aerosol forming liquid. With a higher level of these agents, the user will be provided with a visual cue -namely an increased aerosol level -when the liquid in the container is running low.

The possibility of the aerosol precursor material being a solid or gel is discussed above. In some embodiments, the aerosol precursor material may comprise an "amorphous solid", which may alternatively be referred to as a "monolithic solid" (i.e. non-fibrous). In some embodiments, the amorphous solid may be a dried gel. The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the aerosolisable material may for example comprise from about 50wt%, 60wt% or 70wt% of amorphous solid, to about 90wt%, 95wt% or 100wt% of amorphous solid. In such embodiments, the capsule may be partially or completely formed from the solid or gel aerosol precursor material. The capsule may also contain an additional aerosol precursor material, optionally with a third flavour characteristic.

Along with having a flavour characteristic, the aerosol forming liquid contained in the container and the aerosol precursor material of the capsule may comprise other components. Such components may be conventional in the sense that they are typically included in aerosol precursor materials for e-cigarettes and the like.

In various embodiments of the present disclosure, the aerosol forming liquid contained in the container and/or the aerosol precursor material of the capsule further comprises an active agent. By the term "active agent" is meant any agent which has a biological effect on a subject when the aerosol is inhaled. The one or more active agents may be selected from nicotine, botanicals, and mixtures thereof. The one or more active agents may be of synthetic or natural origin. The active could be an extract from a botanical, such as from a plant in the tobacco family. An example active is nicotine.

Thus in various embodiments, the aerosol forming liquid includes an active agent; preferably the active agent is nicotine. Nicotine may be provided in any suitable amount depending on the desired dosage when inhaled by the user.

In various embodiments, nicotine is present in an amount of no greater than about 6 wt% based on the total weight of the aerosol forming liquid. By the expression "total weight of the aerosol forming liquid" is meant the total weight of the aerosol forming liquid in which the nicotine is present. In various embodiments, nicotine is present in an amount of from about 0.4 to about 6 wt% based on the total weight of the aerosol forming liquid; from about 0.8 to about 6 wt% based on the total weight of the aerosol forming liquid; from about 1 to about 6 wt% based on the total weight of the aerosol forming liquid; or from about 1.8 to about 6 wt% based on the total weight of the aerosol forming liquid.

In other embodiments, nicotine is present in an amount of no greater than about 3 wt% based on the total weight of the aerosol forming liquid. For example, from about 0.4 to about 3 wt%; from about 0.8 to about 3 wt%; from about 1 to about 3 wt%; or from about 1.8 to about 3 wt%, all based on the total weight of the aerosol forming liquid.

In various embodiments, nicotine is present in an amount of less than about 1.9 wt% based on the total weight of the aerosol forming liquid. For example, from about 0.4 to less than about 1.9 wt%; from about 0.5 to less than about 1.9 wt%; or from about 0.6 to less than about 1.9 wt%; all based on the total weight of the aerosol forming liquid.

In various embodiments, the aerosol precursor material contained in or by the capsule also includes an active agent. The active agent present in the aerosol precursor material may be the same or different to the active agent present in the aerosol forming liquid. When the active agent is nicotine, it may be present in the amounts presented above for the aerosol forming liquid, with the wt% values being based on the total weight of the aerosol precursor material.

In various embodiments, the aerosol forming liquid or the aerosol precursor material may contain one or acids. Such acids may be included in addition to nicotine (as the active agent). In various embodiments, the one or more acids may be one or more organic acids. In various embodiments, the one or more acids may be one or more organic acids selected from the group consisting of benzoic acid, levulinic acid, malic acid, maleic acid, fumaric acid, citric acid, lactic acid, acetic acid, succinic acid, and mixtures thereof. When included in in combination with nicotine, the one or more acids may provide a formulation in which the nicotine is at least partially in protonated (such as monoprotonated and/or diprotonated) form.

Along with the component described above, the present disclosure provides an aerosol provision system comprising the component and a power supply. The power supply includes a cell or battery for supplying power. Aerosol provision systems/devices may also be referred to herein as "vapour provision systems/devices", "aerosol delivery devices/systems", "vapour delivery systems/devices", "electronic vapour provision devices/systems", "electronic aerosol provision devices/systems" or "e-cigarettes/electronic cigarettes". These terms may be used interchangeably and are intended to include non-combustible aerosol and vapour provision systems/devices (non-combustible smoking articles) such as: electronic cigarettes or e-cigarettes that create vapour or aerosol from precursor materials by heating or other techniques such as vibration, hybrid systems that provide vapour or aerosol via a combination of precursor materials and solid substrate materials, for example hybrid systems containing liquid or gel precursor materials and a solid substrate material.

In some embodiments, the aerosol provision system is a hybrid system for providing an aerosol by heating, but not burning, a combination of aerosol forming materials. The hybrid system comprises a component of the present disclosure and a substrate material. The substrate material may comprise for example solid, liquid or gel which may or may not contain nicotine. The solid substrate material may be, for example, a tobacco or non-tobacco product, which may or may not contain nicotine. The hybrid system also generally includes a power supply as described herein.

In some embodiments, the aerosol provision system is a non-combustible smoking article such as an electronic cigarette, also known as a vaping device. The aerosol provision system comprises a component of the present disclosure, and generally a power supply as described herein.

The power supply (e.g. a battery) may be present in a control unit with an outer housing, control circuitry for controlling and monitoring the operation of the aerosol provision system, a user input button, and a mouthpiece (which may be detachable). The battery may be rechargeable and be of a conventional type, for example of the kind typically used in electronic cigarettes and other applications requiring provision of relatively high currents over a relatively short period. Similarly, the user input button (or other aerosol generation function) and control circuity may be conventional. The outer housing may be formed, for example, from a plastics or metallic material. Other suitable materials are known in the art.

As will be appreciated, the aerosol provision system will in general comprise various other elements associated with its operating functionality. For example, a port for charging the battery, such as a USB port or the like, and these other elements may be conventional.

In some embodiments the control circuitry is configured to control the supply of electrical power from the battery to the heater in the component. Electrical power may be supplied to the heater via contacts established across the interface between the component and the control unit, for example, through sprung/pogo pin connectors, or any other configuration of electrical contacts which engage when the component is connected to the control unit.

The rate at which the aerosol forming liquid contained in the liquid container is volatilised will depend on the amount of power supplied to the heater. Accordingly, the rate of aerosol generation can be controlled by adjusting the power supplied to the heater, for example through pulse width or frequency modulation techniques. Regardless of how the electrical power, including the relative amount of power, to be delivered to the heater is configured, when the electronic cigarette is in its normal operating mode, a user may press the button to activate the heater in accordance with the configured relative power settings. Although a user button is described, it will be appreciated that the activation of aerosol generation may be based on other techniques. For example, instead of using a button to activate the supply of power to the heater, an inhalation sensor, for example, based around a pressure sensor/microphone arranged to detect a drop in pressure when a user inhales on the device, may be used.

When the aerosol generation function of the aerosol provision system is activated, a user sucks/inhales on the mouthpiece to draw air through the device. Air is drawn from the environment into the device and at least a portion of this air enters an aerosol generation chamber of the component. Accordingly, the incoming air flows past the heater in the chamber while the heater is receiving electrical power from the battery in the control unit so as to generate an aerosol from the relevant aerosol precursor material in the aerosol generation chamber. The volatilised material is then incorporated/entrained into the airflow and drawn through and out of the relevant device for inhalation by a user.

When in a hybrid device, the volatilised material will typically contact and/or pass through the substrate material, e.g. a tobacco material, downstream of the heater before inhalation of the aerosol by a user. The substrate material may be located in the component (e.g. in the aerosol generation chamber thereof) or in an air flow path from an outlet of the component to the mouthpiece or other outlet of the device. The latter may involve the substrate material being in a separate chamber or container which forms part of the airflow path. The person skilled in the art will be aware of suitable configurations for a hybrid device.

During normal use, the control circuitry may be configured to monitor various operational aspects of the aerosol provision system. For example, the control circuitry may be configured to monitor a level of power remaining in the rechargeable battery, and this may be performed in accordance with conventional techniques. Additionally the control circuitry may be configured to estimate a remaining amount of aerosol forming liquid in the liquid container, for example based on an accumulated time of usage since a new component or container was installed, or based on sensing the levels in the container. This may be performed in accordance with any conventional technique(s). The control circuitry may also be configured to estimate a remaining time for the substrate material in a hybrid device, for example, based on an accumulated time of usage since a new substrate material and/or container was installed, or based on sensing the number of puffs on the device. This may be performed in accordance with any conventional technique(s).

If it is determined through monitoring the operational aspects of the aerosol provision system that a certain operating condition has arisen, for example, a container and/or substrate material is approaching depletion, or a battery level is falling below a predetermined threshold (which may be predefined or user set), the aerosol provision system may be configured to provide a user notification according to any conventional technique(s).

Although described with reference to the control circuitry, other user notifications are known in the art and may be implemented herein. In addition, it will be appreciated that there are many other situations in which a user notification might be desired, the present disclosure is not limited to providing notification of low levels of liquid or substrate material or remaining battery power.

In accordance with the present disclosure, however, user notification via the control circuitry or otherwise is not necessary if an "end-of-life" operating condition has arisen. By the term "end-of-life" is meant that the aerosol forming liquid in the liquid container is exhausted such that the aerosol provision system is in the end of its useful life from the point of view of the user or consumer. User notification of an "end-of-life" operating condition or exhaustion is provided by the aerosol precursor material of the capsule as described above.

The method and use provided by the present disclosure involves features which are described above and the person skilled in the art will appreciate that the previously described subject-matter equally applies to this method and use.

It is to be understood that advantages, embodiments, examples, functions, features, structures and/or other aspects of the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claims. Various embodiments may suitable comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. other than those specifically described herein.

Claims

CLAIMS1 A component for an aerosol provision system, the component comprising: a liquid container for containing an aerosol forming liquid; a wick arranged to draw liquid from the liquid container in use; and a heater arranged to volatilise liquid drawn from the liquid container by the wick in use, to generate an aerosol in use; and a capsule for an aerosol precursor material, wherein the capsule is configured to release the aerosol precursor material for volatilisation in response to an increase in temperature of the heater caused by exhaustion of the aerosol forming liquid.
2. A component according to claim 1, wherein the capsule is configured to rupture, degrade or melt in response to the increase in temperature of the heater.
3 A component according to claim 1 or claim 2, wherein the capsule is partially or completely formed from a material which ruptures in response to the increase in temperature of the heater.
4 A component according to any one of claims 1 to 3, wherein the capsule is partially or completely formed from a material which melts or thermally degrades in response to the increase in temperature of the heater.
A component according to any one of the preceding claims, wherein the capsule is partially or completely formed from a microcrystalline wax, a glass or a mixture thereof.
6 A component according to claim 1, wherein the capsule is partially or completely formed from a material which shrinks and thereby ruptures in response to the increase in temperature of the heater.
7 A component according to claim 6, wherein the capsule is partially or completely formed from a plastic material which shrinks and thereby ruptures in response to the increase in temperature of the heater.
8. A component according to any one of the preceding claims, wherein the capsule is configured to release the aerosol precursor material for volatilisation at a temperature of no less than about 250°C.
9 A component according to any one of claims 1 to 7, wherein the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is at least 2°C greater than the maximum temperature at which the heater volatises the liquid drawn from the liquid container by the wick in use.
The component according to any one of claims 1 to 7 or 9, wherein the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is less than the degradation temperature of the wick.
11. The component according to any one of claims 1 to 7 or 9 to 10, wherein the capsule is configured to release the aerosol precursor material for volatilisation at a temperature which is less than the degradation temperature of the aerosol precursor material.
12. A component according to any one of claims 2 to 5, wherein the capsule is configured to rupture or melt at a temperature of from about 250 to about 300°C.
13. A component according to claim 6 or claim 7, wherein the capsule is partially or completely formed from a plastic which has a shrink temperature of no less than about 250°C.
14. A component according any one of the preceding claims, wherein the capsule contains a flavoured liquid or is formed from a flavoured solid or flavoured amorphous solid
15. A component according to any one of the preceding claims, wherein the liquid container contains a flavoured aerosol forming liquid.
16. A component according to claim 14 and claim 15, wherein the flavoured liquid contained in the capsule or the flavoured solid or amorphous solid forming the capsule has a different flavour to the flavoured aerosol forming liquid in the liquid container.
17. A component according to any one of the preceding claims, wherein the wick and the heater are provided by a porous ceramic heater.
18. A component according to any one of the preceding claims, wherein the wick comprises the capsule.
19. A component according to any one of the preceding claims, wherein the liquid container contains an aerosol forming liquid.
20. A component according to any one of the preceding claims, wherein the aerosol forming liquid contains nicotine.
21. An aerosol provision system comprising a component as defined in any one of claims 1 to 20 and a power supply comprising a cell or battery for supplying power to the component.
22 A method of providing an aerosol for inhalation by a user, the method comprising: volatilising, by a heater, aerosol forming liquid drawn in from a liquid container by a wick, thereby generating an aerosol; and on exhaustion of the aerosol forming liquid, allowing an increase in temperature of the heater such that a capsule releases an aerosol precursor material for volatilisation and inhalation by the user, thereby indicating the exhaustion of the aerosol forming liquid.
23. Use of a capsule for an aerosol precursor material to provide an end-of-life flavour to a user of an aerosol provision system.