Patent Description:
Pharmaceutical medicament, physiologically active substances and flavourings for example may be delivered to the human body by inhalation through the mouth and/or nose. Such material or substances may be delivered directly to the mucosa or mucous membrane lining the nasal and oral passages and/or the pulmonary system. For example, nicotine is consumed for therapeutic or recreational purposes and may be delivered to the body in a number of ways. Nicotine replacement therapies are aimed at people who wish to stop smoking and overcome their dependence on nicotine. Nicotine is delivered to the body in the form of aerosol delivery devices and systems, also known as smoking-substitute devices or nicotine delivery devices. Such devices may be non-powered or powered.

Devices or systems that are non-powered may comprise nicotine replacement therapy devices such as "inhalators", e.g. Nicorette® Inhalator. These generally have the appearance of a plastic cigarette and are used by people who crave the behaviour associated with consumption of combustible tobacco - the so-called hand-to-mouth aspect - of smoking tobacco. Inhalators generally allow nicotine-containing aerosol to be inhaled through an elongate tube in which a container containing a nicotine carrier, for example, a substrate, is located. An air stream caused by suction through the tube by the user carries nicotine vapours into the lungs of the user to satisfy a nicotine craving. The container may comprise a replaceable cartridge, which includes a cartridge housing and a passageway in the housing in which a nicotine reservoir is located. The reservoir holds a measured amount of nicotine in the form of the nicotine carrier. The measured amount of nicotine is an amount suitable for delivering a specific number of "doses". The form of the nicotine carrier is such as to allow nicotine vapour to be released into a fluid stream passing around or through the reservoir. This process is known as aerosolization and or atomization. Aerosolization is the process or act of converting a physical substance into the form of particles small and light enough to be carried on the air i.e. into an aerosol. Atomization is the process or act of separating or reducing a physical substance into fine particles and may include the generation of aerosols. The passageway generally has an opening at each end for communication with the exterior of the housing and for allowing the fluid stream through the passageway. A nicotine-impermeable barrier seals the reservoir from atmosphere. The barrier includes passageway barrier portions for sealing the passageway on both sides of the reservoir. These barrier portions are frangible so as to be penetrable for opening the passageway to atmosphere.

A device or a system that is powered can fall into two sub-categories. In both subcategories, such devices or systems may comprise electronic devices or systems that permit a user to simulate the act of smoking by producing an aerosol mist or vapour that is drawn into the lungs through the mouth and then exhaled. The electronic devices or systems typically cause the vaporization of a liquid containing nicotine and entrainment of the vapour into an airstream. Vaporization of an element or compound is a phase transition from the liquid phase to vapour i.e. evaporation or boiling. In use, the user experiences a similar satisfaction and physical sensation to those experienced from a traditional smoking or tobacco product, and exhales an aerosol mist or vapour of similar appearance to the smoke exhaled when using such traditional smoking or tobacco products.

A person of ordinary skill in the art will appreciate that devices or systems of the second, powered category as used herein include, but are not limited to, electronic nicotine delivery systems, electronic cigarettes, e-cigarettes, e-cigs, vaping cigarettes, pipes, cigars, cigarillos, vaporizers and devices of a similar nature that function to produce an aerosol mist or vapour that is inhaled by a user. Such nicotine delivery devices or systems of the second category incorporate a liquid reservoir element generally including a vaporizer or misting element such as a heating element or other suitable element, and are known, inter alia, as atomizers, cartomizers, or clearomizers. Some electronic cigarettes are disposable; others are reusable, with replaceable and refillable parts.

Aerosol delivery devices or systems in a first sub-category of the second, powered category generally use heat and/or ultrasonic agitation to vaporize a solution comprising nicotine and/or other flavouring, propylene glycol and/or glycerine-based base into an aerosol mist of vapour for inhalation.

Aerosol delivery devices or systems in a second sub-category of the second, powered category may typically comprise devices or systems in which tobacco is heated rather than combusted. During use, volatile compounds may be released from the tobacco by heat transfer from the heat source and entrained in air drawn through the aerosol delivery device or system. Direct contact between a heat source of the aerosol delivery device or system and the tobacco heats the tobacco to form an aerosol. As the aerosol containing the released compounds passes through the device, it cools and condenses to form an aerosol for inhalation by the user. In such devices or systems, heating, as opposed to burning, the tobacco may reduce the odour that can arise through combustion and pyrolytic degradation of tobacco.

Aerosol delivery devices or systems falling into the first sub-category of powered devices or systems may typically comprise a powered unit, comprising a heater element, which is arranged to heat a portion of a carrier that holds an aerosol precursor. The carrier comprises a substrate formed of a "wicking" material, which can absorb aerosol precursor liquid from a reservoir and hold the aerosol precursor liquid. Upon activation of the heater element, aerosol precursor liquid in the portion of the carrier in the vicinity of the heater element is vaporised and released from the carrier into an airstream flowing around the heater and carrier. Released aerosol precursor is entrained into the airstream to be borne by the airstream to an outlet of the device or system, from where it can be inhaled by a user.

The heater element is typically a resistive coil heater, which is wrapped around a portion of the carrier and is usually located in the liquid reservoir of the device or system. Consequently, the surface of the heater may always be in contact with the aerosol precursor liquid, and long-term exposure may result in the degradation of either or both of the liquid and heater. Furthermore, residues may build up upon the surface of the heater element, which may result in undesirable toxicants being inhaled by the user. Furthermore, as the level of liquid in the reservoir diminishes through use, regions of the heater element may become exposed and overheat. Example of known devices is given in <CIT> and <CIT>.

At its most general, the present invention proposes a fluid-transfer article according to claim <NUM> and an aerosol generation apparatus according to claim <NUM>.

The second part of the second region has one or more recesses therein opening towards the heater and forming one or more gaps between the activation surface and the heater. The one or more gaps then form at least one air-flow pathway along the activation surface. The gaps may thus form channels in the second part of the second region at the activation surface, along which air may flow.

The separability of the fluid-transfer article and the heater means that it is possible to replace the fluid-transfer article without having to replace the heater. Since the aerosol precursor will be consumed when the apparatus is used by a user, it will normally be necessary to replace or at least refill the fluid-transfer article periodically, as it acts as a reservoir for the aerosol precursor.

The two different materials of the second region of the fluid-transfer article allow one (the material of the second part) to be adapted to the heater, whilst the other (the material of the first part) may be a lower cost material.

As mentioned above the first part of the second region has a plurality of holes therein. Preferably, those holes do not act as capillaries, but instead may be of a size or sizes so that they cooperate with the second part of the second region to define non-capillary spaces in the second region in to which the aerosol precursor is able to flow. Thus, the aerosol precursor may pass from the first region in a non-capillary manner into the holes, and impinge on the second part of the second region. It may then pass through the second part due to the porous nature of the second part.

The second region of the fluid-transfer article may thus act as a wick, to cause aerosol precursor to move from the first region to the activation surface where it may be heated by the heater. The wick may have a two-layer structure, formed by the two parts of the second region. One of those parts is preferably being made of an inexpensive material through which the holes pass, and the second part is of a more heat resistant material, which will interact with the heater at the activation surface. Aerosol precursor will be drawn through the second region, partly because the holes will fill with aerosol precursor, and partly because of the porous nature of the second part of the second region.

Thus, according to the present invention, there may be provided a fluid-transfer article according to claim <NUM> and an aerosol-generation apparatus according to claim <NUM>.

Preferably, said heater is mounted so as to be in contact with at least one part of said activation surface. Then, it is preferable that said heater and said activation surface are separable.

In the present invention, it is normally desirable that said plurality of holes are sized to that they cooperate with said second part of said second region to define non-capillary spaces in said second region into which said aerosol precursor is able to flow from said first region in a non-capillary manner, thereby to impinge on said second part of said second region.

The heater is preferably a coil, mesh or foil.

Preferably, said first part of said second region is formed of a solid polymer material having said plurality of holes therein.

It is usually preferable that said second part of said second region is formed of fibrous material. That fibrous material may be ceramic fibre, glass fibre or carbon fibre. Alternatively, the second part of the second region may be porous glass or porous ceramic. Another possibility is that the second part of the second region is of a porous polymer material. Another possibility is for the first region of the fluid-transfer article to be a simple reservoir filled with liquid aerosol precursor, from which reservoir the liquid flows into the holes in the first part of the second region of the fluid-transfer article.

Preferably, the plurality of holes are moulded holes. As mentioned above, it is desirable that the first part of the second region is formed of solid polymer material and it is then convenient to mould the holes at the same time that the first part itself is moulded.

The fluid-transfer article may act as a reservoir for aerosol precursor. One option is for the first region of said fluid-transfer article to be of porous polymer material.

The porous polymer material of the first region may comprise Polyetherimide (PEI) and/or Polyether ether ketone (PEEK) and/or Polytetrafluoroethylene (PTFE) and/or Polyimide (PI) and/or Polyethersulphone (PES) and/or Ultra-High Molecular Weight Polyethylene (UHMWPE) and/or Polypropylene (PP) and/or Polyethylene Terephthalate (PET). Similar materials may be used for the second part of the second region when that second region is made of a porous polymer material, as mentioned above.

Alternatively, the first region of the fluid-transfer article may be a simple hollow reservoir which is filled with aerosol precursor when the apparatus is to be used.

The aerosol-generation apparatus may form part of an aerosol delivery system which has a carrier which includes a housing containing the fluid-transfer article. The aerosol delivery system may then include a further housing supporting the heater. The housing and the further housing may be mutually separable, to allow the carrier, and hence the fluid-transfer article, to be removed from the rest of the aerosol delivery system.

The further housing may have an inlet with the air-flow pathway extending to the inlet.

In general outline, one or more embodiments in accordance with the present invention may provide a system for aerosol delivery in which an aerosol carrier may be inserted into a receptacle (e.g. a "heating chamber") of an apparatus for initiating and maintaining release of an aerosol from the aerosol carrier. Another end, or another end portion, of the aerosol carrier may protrude from the apparatus and can be inserted into the mouth of a user for the inhalation of aerosol released from the aerosol carrier cartridge during operation of the apparatus.

Hereinafter, and for convenience only, "system for aerosol delivery" shall be referred to as "aerosol delivery system".

Referring now to <FIG>, there is illustrated a perspective view of an aerosol delivery system <NUM> comprising an aerosol generation apparatus <NUM> operative to initiate and maintain release of aerosol from a fluid-transfer article in an aerosol carrier <NUM>. In the arrangement of <FIG>, the aerosol carrier <NUM> is shown with a first end <NUM> thereof and a portion of the length of the aerosol carrier <NUM> located within a receptacle of the apparatus <NUM>. A remaining portion of the aerosol carrier <NUM> extends out of the receptacle. This remaining portion of the aerosol carrier <NUM>, terminating at a second end <NUM> of the aerosol carrier, is configured for insertion into a user's mouth. A vapour and/or aerosol is produced when a heater (not shown in <FIG>) of the apparatus <NUM> heats a fluid-transfer article in the aerosol carrier <NUM> to release a vapour and/or an aerosol, and this can be delivered to the user, when the user sucks or inhales, via a fluid passage in communication with an outlet of the aerosol carrier <NUM> from the fluid-transfer article to the second end <NUM>.

The device <NUM> also comprises air-intake apertures <NUM> in the housing of the apparatus <NUM> to provide a passage for air to be drawn into the interior of the apparatus <NUM> (when the user sucks or inhales) for delivery to the first end <NUM> of the aerosol carrier <NUM>, so that the air can be drawn across an activation surface of a fluid-transfer article located within a housing of the aerosol carrier cartridge <NUM> during use. Optionally, these apertures may be perforations in the housing of the apparatus <NUM>.

A fluid-transfer article <NUM> (not shown in <FIG>, but described hereinafter with reference to <FIG> is located within a housing of the aerosol carrier <NUM>. The fluid-transfer article <NUM> contains an aerosol precursor material, which may include at least one of: nicotine; a nicotine precursor material; a nicotine compound; and one or more flavourings. The fluid-transfer article <NUM> is located within the housing of the aerosol carrier <NUM> to allow air drawn into the aerosol carrier <NUM> at, or proximal, the first end <NUM>, and has first and second regions, as will be described.

The first region of the fluid-transfer article <NUM> may comprise a substrate of porous material where pores of the porous material hold, contain, carry, or bear the aerosol precursor material. In particular, the porous material of the fluid-transfer article may be a porous polymer material such as, for example, a sintered material. Particular examples of material suitable for the fluid-transfer article include: Polyetherimide (PEI); Polytetrafluoroethylene (PTFE); Polyether ether ketone (PEEK); Polyimide (PI); Polyethersulphone (PES); and Ultra-High Molecular Weight Polyethylene. Other suitable materials may comprise, for example, BioVyonTM (by Porvair Filtration Group Ltd) and materials available from Porex®. Further optionally, a substrate forming the fluid-transfer article may comprise Polypropylene (PP) or Polyethylene Terephthalate (PET). All such materials may be described as heat resistant polymeric wicking material in the context of the present invention.

Alternatively, in some embodiments it is envisaged that the first region of the fluid-transfer article <NUM> may take the form of a simple tank having a cavity defining a hollow reservoir to hold the aerosol precursor.

The aerosol carrier <NUM> is removable from the apparatus <NUM> so that it may be disposed of when expired. After removal of a used aerosol carrier <NUM>, a replacement aerosol carrier <NUM> can be inserted into the apparatus <NUM> to replace the used aerosol carrier <NUM>.

<FIG> is a cross-sectional side view illustration of a part of apparatus <NUM> of the aerosol delivery system <NUM>. The apparatus <NUM> comprises a receptacle <NUM> in which is located a portion of the aerosol carrier <NUM>. In one or more optional arrangements, the receptacle <NUM> may enclose the aerosol carrier <NUM>. The apparatus <NUM> also comprises a heater <NUM>, which interacts thermally with an activation surface of the fluid-transfer article <NUM> when an aerosol carrier <NUM> is located within the receptacle <NUM>.

Air flows into the apparatus <NUM> (in particular, into a closed end of the receptacle <NUM>) via air-intake apertures <NUM>. From the closed end of the receptacle <NUM>, the air is drawn into the aerosol carrier <NUM> (under the action of the user inhaling or sucking on the second end <NUM>) and expelled at the second end <NUM>. As the air flows into the aerosol carrier <NUM>, it passes across the activation surface. Heat from the heater <NUM> heats the activation surface of the fluid-transfer article <NUM>, which causes vaporisation of aerosol precursor material at the activation surface of the fluid-transfer article <NUM> and an aerosol is created in the air flowing over the activation surface. Thus, through the application of heat to the activation surface, an aerosol is released, or liberated, from the fluid-transfer article, and is drawn from the material of the aerosol carrier unit by the air flowing across the activation surface and is transported in the air flow to via outlet conduits (not shown in <FIG>) in the housing of the aerosol carrier <NUM> to the second end <NUM>. The direction of air flow is illustrated by arrows in <FIG>.

To achieve release of the captive aerosol from the fluid-transfer article, the activation surface of the fluid-transfer article <NUM> is heated by the heater <NUM>. As a user sucks or inhales on second end <NUM> of the aerosol carrier <NUM>, the aerosol released from the fluid-transfer article and entrained in the air flowing across the activation surface is drawn through the outlet conduits (not shown) in the housing of the aerosol carrier <NUM> towards the second end <NUM> and onwards into the user's mouth.

Turning now to <FIG>, a cross-sectional side view of the aerosol delivery system <NUM> is schematically illustrated showing the features described above in relation to <FIG> and <FIG> in more detail. As can be seen, apparatus <NUM> comprises a housing <NUM>, in which is located the receptacle <NUM>. The housing <NUM> also contains control circuitry (not shown) operative by a user, or upon detection of air and/or vapour being drawn into the device <NUM> through air-intake apertures <NUM>, i.e. when the user sucks or inhales. Additionally, the housing <NUM> comprises an electrical energy supply <NUM>, for example a battery. Optionally, the battery comprises a rechargeable lithium ion battery. The housing <NUM> also comprises a coupling <NUM> for electrically (and optionally mechanically) coupling the electrical energy supply <NUM> to control circuitry (not shown) for powering and controlling operation of the heater <NUM>.

Responsive to activation of the control circuitry of apparatus <NUM>, the heater <NUM> heats the activation surface of the fluid-transfer article <NUM> (not shown in <FIG>). This heating process initiates (and, through continued operation, maintains) release of vapour and/or an aerosol from the activation surface of the fluid-transfer article <NUM>. The vapour and/or aerosol formed as a result of the heating process is entrained into a stream of air being drawn across the activation surface of the fluid-transfer article <NUM> (as the user sucks or inhales). The stream of air with the entrained vapour and/or aerosol passes through the aerosol carrier <NUM> via outlet conduits (not shown) and exits the aerosol carrier <NUM> at second end <NUM> for delivery to the user. This process is briefly described above in relation to <FIG>, where arrows schematically denote the flow of the air stream into the device <NUM> and through the aerosol carrier <NUM>, and the flow of the air stream with the entrained vapour and/or aerosol through the aerosol carrier cartridge <NUM>.

<FIG> and <FIG> schematically illustrate the aerosol carrier <NUM> in more detail (and, in <FIG>, features within the receptacle in more detail). <FIG> illustrates an exterior of the aerosol carrier <NUM>, and <FIG> illustrates internal components of the aerosol carrier <NUM> in one optional configuration.

<FIG> illustrates the exterior of the aerosol carrier <NUM>, which comprises housing <NUM> for housing said fluid-transfer article (not shown). The particular housing <NUM> illustrated in <FIG> comprises a tubular member, which may be generally cylindrical in form, and which is configured to be received within the receptacle of the apparatus. First end <NUM> of the aerosol carrier <NUM> is for location to oppose the heater of the apparatus, and second end <NUM> (and the region adjacent the second end <NUM>) is configured for insertion into a user's mouth.

<FIG> illustrates some internal components of the aerosol carrier <NUM> and of the heater <NUM> of apparatus <NUM>, in one embodiment of the invention.

As described above, the aerosol carrier <NUM> comprises a fluid-transfer element <NUM>. At least part of the fluid-transfer article <NUM> may be removable from the housing <NUM>, to enable it to be replaced. The fluid-transfer article <NUM> acts as a reservoir for aerosol precursor and that aerosol precursor will be consumed as the apparatus is used. Once sufficient aerosol precursor has been consumed, the aerosol precursor will need to be replaced. It may then be easiest to replace it by replacing the fluid-transfer article <NUM>, rather than trying to re-fill the fluid-transfer article <NUM> with aerosol precursor while it is in the housing <NUM>.

In the illustrated embodiments, the fluid-transfer article <NUM> has a first region <NUM> formed by layers 35a and 35b, and a second region <NUM>. That second region <NUM> has a first part being an upper layer 36a which is formed by a plate with a plurality of holes <NUM> therein, and a second part being a lower layer formed by a second plate 36b made of a porous material which allows aerosol precursor to pass therethrough. In the arrangement of <FIG>, the plate 36a with holes <NUM> therein is in contact with the first region <NUM> of the fluid-transfer article <NUM>, so that aerosol precursor may pass from that first region <NUM> directly into the holes <NUM>, and through those holes to the second plate 36b.

Since the second plate 36b is porous, the aerosol precursor will pass to the surface of the plate 36b remote from the first region <NUM> of the fluid-transfer article <NUM>, which surface acts as an activation surface <NUM> of the fluid-transfer article <NUM>. A heater is mounted so as to contact the activation surface <NUM>. When the heater <NUM> is activated, the heat which it generates will be transferred to the activation surface <NUM>.

Further components not shown in <FIG> comprise: an inlet conduit, via which air can be drawn into the aerosol carrier <NUM>; an outlet conduit, via which an air stream entrained with aerosol can be drawn from the aerosol carrier <NUM>; a filter element; and a reservoir for storing aerosol precursor material and for providing the aerosol precursor material to the fluid-transfer article <NUM>.

In <FIG>, the aerosol carrier is shown as comprising the fluid-transfer article <NUM> located within housing <NUM>. The fluid transfer article <NUM> comprises a first region <NUM> holding an aerosol precursor. In one or more arrangements, the first region of <NUM> of the fluid transfer article <NUM> comprises a reservoir for holding the aerosol precursor. The first region <NUM> can be the sole reservoir of the aerosol carrier <NUM>, or it can be arranged in fluid communication with a separate reservoir, where aerosol precursor is stored for supply to the first region <NUM>. As shown in <FIG>, the first region <NUM> has a first layer 35a and a second layer 35b. The material forming the first layer 35a of the first region <NUM> comprises a porous structure, whose pore diameter size varies between one end of the first layer 35a and another end of the first layer 35a. The pore diameter size may increase from a first end remote from heater <NUM> (the upper end is as shown in the figure) to a second end. The pore diameter size may change in a step-wise manner (i.e. a first part with pores having a diameter of first size, and a second part with pores having a diameter of second, smaller size), or the change in pore size in the first layer 35a may be gradual rather than step-wise. This configuration of pores having a decreasing diameter size can provide a wicking effect, which can serve to draw fluid through the first layer 35a, towards heater <NUM>.

The first region <NUM> of the fluid transfer article <NUM> may also comprise a second layer 35b. Aerosol precursor is drawn from the first layer 35a to the second layer 35b by the wicking effect of the material forming the first layer 35a. Thus, the first layer 35a is configured to transfer the aerosol precursor to the second layer 35b of the first region <NUM> of the fluid-transfer article <NUM>.

The second layer 35b itself may comprise a porous structure formed by a porous polymer material. It is then preferable that the pore diameter size of the porous structure of the second layer 35b is smaller than the pore diameter size of the immediately adjacent part of the first layer 35a. As mentioned above, the porous polymer material may be a sintered material. Particular examples of material suitable for the fluid-transfer article include: Polyetherimide (PEI); Polytetrafluoroethylene (PTFE); Polyether ether ketone (PEEK); Polyimide (PI); Polyethersulphone (PES); and Ultra-High Molecular Weight Polyethylene. Other suitable materials may comprise, for example, BioVyonTM (by Porvair Filtration Group Ltd) and materials available from Porex®. Further optionally, a substrate forming the fluid-transfer article may comprise Polypropylene (PP) or Polyethylene Terephthalate (PET).

However, as mentioned previously, in some embodiments it is envisaged that the first region <NUM> of the fluid-transfer article need not be of porous polymer material as described above. Instead, the first region <NUM> of the fluid-transfer article <NUM> may take the form of a simple tank having a cavity defining a hollow reservoir to hold the aerosol precursor. In such embodiments it is proposed that the plate 36a with holes <NUM> therein will extend across the bottom of the tank so that aerosol precursor held in the tank will impinge directly on the plate 36a and pass directly from the tank defining the first region <NUM> of the fluid-transfer article <NUM> into the holes <NUM> of the second region <NUM> of the fluid-transfer article.

As illustrated in <FIG>, the second plate 36b of second region <NUM> has a plurality of recesses <NUM> therein so that the activation surface <NUM> is convoluted, with parts in contact with the heater <NUM>, and parts at the recesses <NUM> are spaced from the heater <NUM> to form the air-flow pathways along the activation surface <NUM>, through which air can pass as it flows from the apertures <NUM> to the second end <NUM>. The recesses <NUM> form channels for the air-flow pathways.

In <FIG>, the recesses are rectangular in cross-section. Other shapes are also possible, such as square, V-shaped, or curved or arched.

As discussed above, the heater <NUM> transfers heat to the activation surface <NUM> thereby releasing aerosol precursor which has reached that activation surface <NUM> through the porous polymer material (or hollow reservoir) of the first region <NUM>, and through the second region <NUM>. That vapour and/or a mixture of vapour and aerosol, may then pass into the air adjacent the activation surface <NUM> and the heater <NUM>. In particular, the vapour or mixture will pass into the spaces (channels) formed by the recesses <NUM>, from the walls of those recesses. The sizes of the recesses <NUM>, and the sizes of the parts of the activation surface <NUM> in contact with the heater <NUM> are chosen so as to balance the need for the heater <NUM> to heat the second part 36b of the intermediate structure <NUM> to release vapour from the activation surface <NUM>, and the need for the recesses <NUM> to be large enough to permit an adequate flow of air along the air-flow pathways.

There is thus a fluid-flow path for air (hereinafter referred to as an air-flow pathway) along each of the channels formed by the recesses <NUM>, linking the apertures <NUM> and the second end <NUM> of the aerosol carrier. When the user sucks or inhales, air is drawn along the air-flow pathways, along the activation surface <NUM> through the channels formed by the recesses <NUM>.

One or more droplets of the aerosol precursor will be released from the second plate 36b and heated, to release vapour or a mixture of aerosol and vapour into the air flowing in the air-flow pathway or pathways. The vapour or mixture passes, as the user sucks and inhales, to the second end <NUM>.

As mentioned above, the second region <NUM> of the fluid-transfer article <NUM> comprises a first plate 36a and a second plate 36b. The first plate 36a may be a moulded polymer disc so that is then easy to form the holes <NUM> therein by moulding the holes <NUM> when the plate 36a is itself moulded. The holes <NUM> are sufficiently large that they do not act as a capillaries, but instead define non-capillary spaces in the second region <NUM>. Hence, aerosol precursor is able to pass from the first region <NUM> of the fluid-transfer article to the second region <NUM> in a non-capillary manner, into the holes <NUM>, and then pass through the second plate 36b to the heater or heaters <NUM>. The holes <NUM> may be relatively large, so that they fill with aerosol precursor when the apparatus is in use.

The second plate 36b is made of a porous material which is more heat-resistant than the material of the plate 36a, as it is acted on directly by the heater <NUM>. It may be fibrous, made from e.g. ceramic fibre, glass fibre or carbon fibre. Alternatively, it may be formed from a high-temperature porous material such as porous glass or porous ceramic. Another possibility is that the second plate 36b may be of a porous polymer material, such as the materials described previously with reference to the layers 35a and 35b of the first region <NUM>, provided that the polymer material is sufficiently resistant to the high temperatures to which it will be subject due to the heater or heaters <NUM>.

It is thought that the flow of air in the recesses <NUM> along the activation surface <NUM> and past the heater <NUM> will have the effect of creating the lower air pressure adjacent the activation surface <NUM> which will tend to draw liquid through the porous second plate 36b to the activation surface <NUM>. Thus, the transfer of aerosol precursor from the fluid-transfer article <NUM> is facilitated.

As mentioned above, the fluid-transfer article <NUM>, formed by the first and second regions <NUM> and <NUM> and any further reservoir of aerosol precursor, forms the consumable part of the apparatus, in the sense that it can readily be replaced to enable the aerosol precursor to be replaced once it is consumed. The heater <NUM> is not part of the consumable elements. Thus, the housing <NUM> containing the fluid-transfer article <NUM> may be separable from a housing <NUM> supporting the heater <NUM> along the line B-B in <FIG>. The further housing <NUM> may be integral with the housing <NUM> containing the electrical energy supply <NUM>. It is for this reason that the heater <NUM> makes contact with, but is not bonded to, the activation surface <NUM>. The contact ensures the most efficient heat transfer from the heater <NUM> to the second plate 36b to heat the activation surface <NUM> but the heater <NUM> must be separable from that activation surface <NUM> to allow removal of the housing <NUM> from the further housing <NUM> when the fluid-transfer article <NUM> has become depleted. The line B to B may therefore correspond to the part of the activation surface <NUM> which contacts the heater <NUM>.

In <FIG>, the heater <NUM> may be a coil, mesh or foil heater such as a radial or Clapton coil. Such a coil, mesh or foil heater is preferred so that any restriction caused by the heater <NUM> on release of aerosol or vapour from the activation surface <NUM> is minimised.

In the illustrative examples of <FIG>, the first layer 35a of the first region <NUM> of the fluid-transfer article <NUM> is located at an "upstream" end of the fluid-transfer article <NUM> and the second plate 35b of the second region 35b is located at a downstream" end of the fluid-transfer article <NUM>. That is, aerosol precursor is wicked, or is drawn, from the "upstream" end of the fluid-transfer article <NUM> to the "downstream" end of the fluid-transfer article <NUM> (as denoted by arrow A in <FIG>).

In <FIG>, the heater <NUM> contacts the parts of the second plate 36b between the recesses <NUM>. It thus makes direct (though unbonded) contact with parts of the activation surface <NUM>. This ensures good heat transfer from the heater <NUM> to the second plate 36b, hence heating the activation surface <NUM>, both where the activation surface <NUM> contacts the heater <NUM> and at the recesses <NUM>. It would be possible for the heater <NUM> to be spaced from the second plate 36b, but this is not preferred, both because the first transfer would be less efficient, and also because there would then be some air flow between the heater <NUM> and the activation surface <NUM> not through the channels formed by the recesses <NUM>.

In the arrangements shown in <FIG>, the ends of the channels formed by the recesses <NUM> are on opposite sides of the housing <NUM>. <FIG> and <FIG> show an alternative configuration, in which the fluid-transfer article is annular, and both the first region <NUM> and the second region <NUM> are then in the form of annuli. In <FIG> and <FIG>, the structure of the fluid-transfer article <NUM>, including the first region <NUM> and the second region <NUM> may correspond generally to that shown in <FIG>. The internal structure of the first and second regions <NUM> and <NUM> may be the same as in <FIG>, but are not illustrated in detail in <FIG> and <FIG> for simplicity. However, the air flow in the apparatus is discussed in more detail below. Thus, <FIG> and <FIG> illustrate an aerosol carrier <NUM> according to one or more possible arrangements in more detail. <FIG> is a cross-section side view illustration of the aerosol carrier <NUM> and <FIG> is a perspective cross-section side view illustration of the aerosol carrier <NUM>.

As can be seen from <FIG> and <FIG>, the aerosol carrier <NUM> is generally tubular in form. The aerosol carrier <NUM> comprises housing <NUM>, which defines the external walls of the aerosol carrier <NUM> and which defines therein a chamber in which are disposed the fluid-transfer article <NUM> (adjacent the first end <NUM> of the aerosol carrier <NUM>) and internal walls defining the fluid communication pathway <NUM>. Fluid communication pathway <NUM> defines a fluid pathway for an outgoing air stream from the channels <NUM> to the second end <NUM> of the aerosol carrier <NUM>. In the examples illustrated in <FIG> and <FIG>, the fluid-transfer article <NUM> is an annular shaped element located around the fluid communication pathway <NUM>. The housing <NUM> containing the fluid-transfer article <NUM> is separable from the housing <NUM> supporting the heater <NUM>.

In walls of the housing <NUM>, there are provided inlet apertures <NUM> to provide a fluid communication pathway for an incoming air stream to reach the activation surface <NUM> of the second region <NUM> of the fluid-transfer article <NUM>.

In the illustrated example of <FIG> and <FIG>, the aerosol carrier <NUM> further comprises a filter element <NUM>. The filter element <NUM> is located across the fluid communication pathway <NUM> such that an outgoing air stream passing through the fluid communication pathway <NUM> passes through the filter element <NUM>.

With reference to <FIG>, when a user sucks on a mouthpiece of the apparatus (or on the second end <NUM> of the aerosol carrier <NUM>, if configured as a mouthpiece), air is drawn into the carrier through inlet apertures <NUM> extending through walls in the housing <NUM> of the aerosol carrier <NUM>.

An incoming air stream 42a from a first side of the aerosol carrier <NUM> is directed to a first side of the second region <NUM> (e.g. via a gas communication pathway within the housing of the carrier). An incoming air stream 42b from a second side of the aerosol carrier <NUM> is directed to a second side of the second region <NUM> (e.g. via a gas communication pathway within the housing of the carrier). When the incoming air stream 42a from the first side of the aerosol carrier <NUM> reaches the first side of the second region <NUM>, the incoming air stream 42a from the first side of the aerosol carrier <NUM> flows along the activation surface <NUM> of the second region <NUM> through the recesses <NUM> in the second plate 36b. Likewise, when the incoming air stream 42b from the second side of the aerosol carrier <NUM> reaches the second side of the second region <NUM>, the incoming air stream 42b from the second side of the aerosol carrier <NUM> flows along the activation surface <NUM> of the second region <NUM>, again through the recesses in the second plate 36b. The air streams from each side are denoted by dashed lines 44a and 44b in <FIG>. As these air streams 44a and 44b flow, aerosol precursor on the activation surface <NUM> of the second region <NUM> is entrained in air streams 44a and 44b.

In use, the heater <NUM> of the apparatus <NUM> raise a temperature of the second plate 36b of the second region <NUM> to a sufficient temperature to release, or liberate, captive substances (i.e. the aerosol precursor) to form a vapour and/or aerosol, which is drawn downstream. As the air streams 44a and 44b continue their passages, more released aerosol precursor is entrained within the air streams 44a and 44b. When the air streams 44a and 44b entrained with aerosol precursor meet at a mouth of the outlet fluid communication pathway <NUM>, they enter the outlet fluid communication pathway <NUM> and continue until they pass through filter element <NUM> and exit outlet fluid communication pathway <NUM>, either as a single outgoing air stream, or as separate outgoing air streams <NUM> (as shown). The outgoing air streams <NUM> are directed to an outlet, from where it can be inhaled by the user directly (if the second end <NUM> of the aerosol capsule <NUM> is configured as a mouthpiece), or via a mouthpiece. The outgoing air streams <NUM> entrained with aerosol precursor are directed to the outlet (e.g. via a gas communication pathway within the housing of the carrier).

<FIG> is an exploded perspective view illustration of a kit-of-parts for assembling an aerosol delivery system <NUM>.

As will be appreciated, in the arrangements described above, the fluid-transfer article <NUM> is provided within a housing <NUM> of the aerosol carrier <NUM>. In such arrangements, the housing of the carrier <NUM> serves to protect the aerosol precursor-containing fluid-transfer article <NUM>, whilst also allowing the carrier <NUM> to be handled by a user without his/her fingers coming into contact with the aerosol precursor liquid retained therein.

In any of the embodiments described above the second plate 36b of the second region <NUM> may have a thickness of less than <NUM>. In other embodiments it may have a thickness of: less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, less than <NUM>, or less than <NUM>.

While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art while remaining within the scope of the appended claims.

Claim 1:
A fluid-transfer article (<NUM>) comprising a first region (<NUM>) for holding an aerosol precursor and for transferring said aerosol precursor to a second region (<NUM>) of said fluid-transfer article (<NUM>), said second region (<NUM>) comprising a first part (36a), said first part (36a) being adjacent said first region (<NUM>) and having a plurality of holes (<NUM>) therein, and a second part (36b) adjacent to said first part (36a) and extending across said plurality of holes in said first part;
wherein said second part (36b) of said second region (<NUM>) has at least one recess (<NUM>) therein for opening towards a heater (<NUM>) of an aerosol generation apparatus, said at least one recess (<NUM>) being configured to form at least one gap between said activation surface (<NUM>) and said heater (<NUM>), said at least one gap forming at least one air-flow pathway along said activation surface (<NUM>);
characterized in that said second part (36b) of said second region (<NUM>) is porous for passage there-through of said aerosol precursor from said plurality of holes to an activation surface (<NUM>) of said second region (<NUM>) for thermal interaction with said heater (<NUM>).