WO2023052085A1

WO2023052085A1 - Vaporisable liquid for a smoking substitute apparatus

Info

Publication number: WO2023052085A1
Application number: PCT/EP2022/075124
Authority: WO
Inventors: Samantha MURRAY; Ian Stuart; Steven Maxwell-Hogg
Original assignee: Nerudia Limited
Priority date: 2021-09-30
Filing date: 2022-09-09
Publication date: 2023-04-06

Abstract

A vaporisable liquid for a smoking substitute apparatus, the vaporisable liquid comprising vegetable glycerine, propylene glycol, and water; wherein the vaporisable liquid comprises less than 5 wt% water and the ratio by mass of propylene glycol to vegetable glycerine is at least 30:70. The vaporisable liquid finds use as an e-liquid in a smoking substitute device.

Description

VAPORISABLE LIQUID FORA SMOKING SUBSTITUTE APPARATUS

Related applications

This application claims the priority of European patent application EP 21200159.8 filed on 30 September 2021 , the contents of which are incorporated herein by reference in their entirety.

Field of the Invention

The present invention relates to a vaporisable liquid for a smoking substitute apparatus and a smoking substitute apparatus that is able to deliver an aerosol vapour generated from the vaporisable liquid to a user.

Background

The smoking of tobacco is generally considered to expose a smoker to potentially harmful substances. It is generally thought that a significant amount of the potentially harmful substances are generated through the heat caused by the burning and/or combustion of the tobacco and the constituents of the burnt tobacco in the tobacco smoke itself.

Combustion of organic material such as tobacco is known to produce tar and other potentially harmful byproducts. There have been proposed various smoking substitute systems in order to avoid the smoking of tobacco.

Such smoking substitute systems can form part of nicotine replacement therapies aimed at people who wish to stop smoking and overcome a dependence on nicotine.

Smoking substitute systems include electronic systems that permit a user to simulate the act of smoking by producing an aerosol (also referred to as a “vapour”) that is drawn into the lungs through the mouth (inhaled) and then exhaled. The inhaled aerosol typically bears nicotine and/or a flavourant without, or with fewer of, the odour and health risks associated with traditional smoking.

In general, smoking substitute systems are intended to provide a substitute for the rituals of smoking, whilst providing the user with a similar experience and satisfaction to those experienced with traditional smoking and with combustible tobacco products.

The popularity and use of smoking substitute systems has grown rapidly in the past few years. Although originally marketed as an aid to assist habitual smokers wishing to quit tobacco smoking, consumers are increasingly viewing smoking substitute systems as desirable lifestyle accessories. There are a number of different categories of smoking substitute systems, each utilising a different smoking substitute approach.

One approach is the so-called “vaping” approach, in which a vaporisable liquid, typically referred to (and referred to herein) as “e-liquid”, is heated by a heating device (referred to herein as an electronic cigarette or “e-cigarette” device) to produce an aerosol vapour which is inhaled by a user. The e-liquid typically includes a base liquid as well as nicotine and/or a flavourant. The resulting vapour therefore also typically contains nicotine and/or a flavourant. A typical e-cigarette device includes a mouthpiece, a power source (typically a battery), a tank for containing e-liquid, as well as a heating device. In use, electrical energy is supplied from the power source to the heating device, which heats the e-liquid to produce an aerosol (or “vapour”) which is inhaled by a user through the mouthpiece.

E-cigarettes can be configured in a variety of ways. For example, there are “closed system” vaping smoking substitute systems, which typically have a sealed tank and heating element. The tank is pre-filled with e-liquid and is not intended to be refilled by an end user. One subset of closed system vaping smoking substitute systems includes a main body which includes the power source, wherein the main body is configured to be physically and electrically coupled to a consumable including the tank and the heating element. In this way, when the tank of a consumable has been emptied, that consumable is disposed of. The main body can be reused by connecting it to a new, replacement, consumable. Another subset of closed system vaping smoking substitute systems are completely disposable, and intended for one-use only.

There are also “open system” vaping smoking substitute systems which typically have a tank that is configured to be refilled by a user. In this way the entire device can be used multiple times.

An example vaping smoking substitute system is the myblu™ e-cigarette. The myblu™ e-cigarette is a closed system which includes a main body and a consumable. The main body and consumable are physically and electrically coupled together by pushing the consumable into the main body. The main body includes a rechargeable battery. The consumable includes a mouthpiece, a sealed tank which contains e-liquid, as well as a heater, which for this device is a heating filament coiled around a portion of a wick. The wick is partially immersed in the e-liquid and conveys e-liquid from the tank to the heating filament. The device is activated when a microprocessor on board the main body detects a user inhaling through the mouthpiece. When the device is activated, electrical energy is supplied from the power source to the heating device, which heats e-liquid from the tank to produce a vapour which is inhaled by a user through the mouthpiece.

For a smoking substitute device, it is desirable to deliver nicotine into the user’s lungs, where it can be absorbed into the bloodstream. As explained above, in the so-called “vaping” approach, e-liquid is heated by a heating device to produce an aerosol vapour which is inhaled by a user. Many e-cigarettes also deliver flavour to the user to enhance the experience. In such e-cigarettes, flavour compounds are contained in the e-liquid that is heated. However, toxicology restrictions are placed on the amount of flavour that can be contained in the e-liquid, and this can result in some e-liquid flavours delivering a weak and underwhelming taste sensation to consumers in the pursuit of safety.

The present disclosure has been devised in the light of the above considerations. Summary of the Invention

At its most general, the present invention relates to a vaporisable liquid for a smoking substitute apparatus, wherein the vaporisable liquid is flavourless. That is, the e-liquid contains no flavourants. The e-liquid may, for example, comprise a base liquid and e.g. nicotine.

According to a first aspect there is provided a vaporisable liquid for a smoking substitute apparatus, the vaporisable liquid comprising vegetable glycerine (VG; also referred to as “glycerol”, “glycerin” and “propane-1 ,2, 3-triol”), propylene glycol (PG; also referred to as “propane-1 ,2-diol”) and water; wherein the vaporisable liquid comprises less than 5 wt% water and the ratio by mass of propylene glycol to vegetable glycerine is at least 30:70. In this way, the present invention provides an e-liquid which is substantially flavourless, in particular, by containing no flavourants, the mixture of VG to PG of the present invention ensures that there is little to no perceivable flavour in an aerosol vapour which is generated from the e- liquid.

Vegetable glycerine (VG) and propylene glycol (PG) are two compounds with their own characteristics.

For example, although vegetable glycerine has a flavour and a sweetness which may be detectable by a user of a smoking substitute apparatus when present in the e-liquid, propylene glycol is tasteless and odourless. By providing a ratio by mass of PG to VG of at least 30:70 the flavour of VG is diluted by the addition of PG, such that there is little to no perceivable flavour in the combination vapour.

In addition, the vapour temperature of VG is lower than that of PG, and so by providing a mixture of PG and VG the mixture is easier to vaporise as compared to PG alone and less hot to a user. In some arrangements, this may prolong the battery life of a smoking substitute device.

The vapour density of VG is also greater than that of PG, and so the aerosol vapour of the mixture may have a preferred mouthfeel for a user compared with a vaporisable liquid of PG alone.

The mixture also provides advantages to the smoking substitute device. For example, VG has a higher viscosity than PG. VG is therefore absorbed into a wick (see below) more slowly than PG. By introducing an amount of PG into the mixture the wick absorption time may be reduced, ensuring good operation of the smoking substitute device, reduced viscosity of the e-liquid is especially advantageous in smoking substitute devices having a small atomiser.

A PG/VG mixture (for example, in an e-liquid) also leads to a reduction in the build-up of gunk or residue within the smoking substitute device compared to VG alone, which a user may find particularly advantageous to reduce the frequency of blockages.

It is desirable for many users to receive a smell and/or flavour when using a smoking substitute apparatus. By providing an e-liquid according to the present invention, a smoking substitute device may be provided in which flavour is delivered to a user of the smoking substitute apparatus by a separate flavour delivery article. As only one e-liquid needs to be provided, which is suitable for uses across all different flavours and smoking substitute device configurations, the cost of manufacturing the e-liquid is reduced, and the e-liquid may itself be easier to manufacture. Furthermore, it is easier for a user to customise their experience in using the smoking substitute device by choosing a desired separate flavour delivery article. Providing a flavourant that is separate to the e-liquid may provide more versatility in how flavour can be delivered to the user.

Vaporised PG is an extremely efficient carrier for flavour. By introducing an amount of PG into the mixture, the amount of flavour transported to a consumer from a flavour delivery article can be increased. Therefore, a more intense flavour can be achieved.

The ratio by mass of PG to VG is at least 30:70. For example, the ratio by mass of PG to VG may be between 30:70 and 90:10, between 30:70 and 80:20, between 30:70 and 75:25, between 30:70 and 70:30, or between 30:70 and 65:35.

The presence of water also serves to increase the amount of flavour transported to a consumer from a flavour delivery article. When the flavour delivery article comprises a scented substrate, for example, a granulated mix comprising a disintegrant, (see below), a small amount of water in the vapour passing over the scented substrate (e.g., granulated mix comprising a disintegrant) creates an aqueous environment that promotes the activation of disintegrant and break-up of substrate (e.g., the granules) to increase the surface area of the substrate (e.g., granules) and promote more rapid release of flavour.

This effect is best produced when the vaporisable liquid comprises less than 5 wt% water. For example, the vaporisable liquid may comprise less than 4 wt% water. The vaporisable liquid may comprise less than 3 wt% water. The vaporisable liquid may comprise less than 2 wt% water. The vaporisable liquid may comprise less than 1 wt% water.

Advantageously, the amount of water in the vapourisable liquid is from 0.25 wt% to less than 5 wt%, such as between 0.5 wt% and 4 wt%, between 0.75 wt% and 3 wt%, or between 1 wt% and 2 wt%. For example the amount of water in the vapourisable liquid may be about 0.3 wt%, about 0.35 wt%, about 0.4 wt%, about 0.45 wt%, about 0.5 wt%, about 0.75 wt%, about 1 wt%, about 1 .25 wt%, about 1 .5 wt%, about 1 .75 wt%, about 2 wt%, about 2.25 wt%, about 2.5 wt%, about 2.75 wt%, about 3 wt%, about 3.25 wt%, about 3.5 wt%, about 3.75 wt%, about 4 wt%, about 4.25 wt%, about 4.5 wt%, about 4.75 wt%, or about 4.95 wt%.

Certain values of ratio by mass of PG to VG have been found to be particularly advantageous.

Increasing the ratio by mass of PG to VG may lead to mixtures which favour the properties of PG. A higher PG to VG ratio may lead to mixtures having a higher vapour temperature, lower viscosity, reduced vapour density, improved flavour carrying characteristics, reduced likelihood of blockages in a smoking substitute device. For example the ratio by mass of PG to VG may be at least 35:65, at least 40:60, at least 45:55, at least 50:50, at least 55:45, at least 60:40, at least 65:35, or at least 70:30.

It may be particularly preferred for the ratio by mass of PG to VG to be at least 60:40. Providing such high PG:VG ratios delivers significant advantages. Firstly, since VG has a flavour and a sweetness which may be detectable by a user, increasing the proportion of flavourless PG reduces interference with separate flavour delivered by a separate flavour delivery substrate or article within the device. Without wishing to be bound by theory, it is believed that at ratios of at least 60:40 any flavour contained in the VG becomes imperceptible to the user such that the e-liquid is essentially flavourless. Secondly, increasing the proportion of PG to achieve a ratio by mass of PG to VG of at least 60:40 reduces the viscosity of the e- liquid, thereby increasing the efficiency of the wicking process which is particularly advantageous for small atomisers.

In addition, the high mass ratio of PG to VG results in an e-liquid that produces a vapour that is an extremely efficient flavour carrier. Therefore, the vaporisable liquid vapour is able to carry sufficient flavour from a flavour delivery article such that any sweetness resulting from the VG present in the e- liquid is imperceptible at the point of use. Furthermore, the increased delivery of flavour from a flavour delivery article, by a vaporisable liquid having a ratio by mass of PG to VG of at least 60:40, may improve the experience of a user of a smoking substitute device, by delivering a more intense flavour.

When the ratio by mass of PG to VG is between 30:70 and 40:60, the ratio of PG to VG ensures that there is little to no perceivable flavour in an aerosol vapour which is generated from the e-liquid.

It has also been found that a mixture of PG to VG in a ratio between 30:70 and 40:60 provides a good balance across the characteristics of PG and VG to provide an aerosol vapour which is particularly pleasant for a user of a smoking substitute device. For example, by providing a mixture that has a vapour temperature which is pleasant for a user (e.g., less hot than PG alone). In some arrangements, reduced vapour temperature may prolong the battery life of a smoking substitute device. In addition, the vapour density of mixtures of PG and VG in this range may result in an aerosol vapour of the mixture having a preferred mouthfeel for a user. The mixture also provides advantages to the smoking substitute device. For example, mixtures of PG and VG in this mass ratio range also benefit from advantageous wick absorption times, ensuring good operation of the smoking substitute device and reduced the build-up of gunk or residue within the smoking substitute device, which a user may find particularly advantageous.

The ratio by mass of PG to VG may be between 30:70 and 40:60, between 31 :69 and 39:61 , between 32:68 and 38:62, between 33:67 and 37:63, or between 34:66 and 36:64. For example, the ratio by mass of PG to VG may be about 30:70, about 31 :69, about 32:68, about 33:67, about 34:66, about 35:65, about 36:64, about 37:63, about 38:62, about 39:61 , or about 40:60. The ratio by mass of PG to VG may be between 35:65 and 40:60.

Advantageously, the ratio by mass of PG to VG may be 65:35. It has been found that this is an optimal ratio for providing a flavourless and odourless vapour in a smoking substitute system. In particular, this ratio provides an optimal balance between the characteristics mentioned above, such as the ease with which the e-liquid may be vaporised, and the mouthfeel of the aerosol vapour.

When the ratio by mass of PG to VG is between 30:70 and 40:60, such as 35:65, the resulting e-liquid may be substantially flavourless (e.g. by the absence of addition of a flavourant to the e-liquid). Therefore, a flavourant delivered with the vapour may require a smaller amount to be sufficiently tasted or smelled by a user. For example, mixtures having a PG to VG mass ratio between 30:70 and 40:60 may provide reduced interference in flavour of a flavourant from the residual flavour of VG. As such, a smaller amount of flavourant delivered from a flavour delivery article may produce a pleasant experience for a user of a substitute smoking device. Therefore, the amount of water in the vaporisable liquid may be reduced, such as less than 0.25 wt% water. This reduced amount of water may result in a slower disaggregation of a scented substrate, and therefore slower (and so, less intense) flavour deliver. In some arrangements, this may prolong the useful life of a flavour delivery article, such as, in terms of the number of “puffs” for which flavour will be delivered.

Optionally, the vaporisable liquid may further comprise nicotine. In this way the e-liquid is particularly suitable for use as an aid to assist habitual smokers wishing to quit tobacco smoking.

Conveniently, the vaporisable liquid may comprise 5% or less by mass nicotine, wherein the total mass of vegetable glycerine, propylene glycol, water and nicotine is 100%. For example, the vaporisable liquid may comprise 4% or less by mass nicotine, such as 3% or less by mass nicotine, or 2% or less by mass nicotine, in particular 1% or less by mass nicotine. Preferably, the vaporisable liquid comprises at least 1% by mass nicotine.

In some embodiments, the vaporisable liquid contains no further flavourants, wherein the term “flavourant” is used to describe a compound or combination of compounds that provide flavour and/or aroma. In this way, a flavourless e-liquid is provided which is simple to manufacture and provides for the separate delivery of flavour to the user, for example from a separate flavour delivery substrate or article within the device, without the risk of interference with flavourants within the vaporisable liquid.

In some embodiments, the vaporisable liquid consists of vegetable glycerine, propylene glycol, and water. In other words, in some embodiments the vaporisable liquid contains only those three components and no further components of any kind. This provides a simple, flavourless composition which is easy to manufacture and has good properties for vaporisation and flavour entrainment.

According to a second aspect of the invention there is provided a smoking substitute kit comprising a vaporisable liquid according to the first aspect of the invention, and a smoking substitute apparatus for generating an aerosol from the vaporisable liquid. In this way, the second aspect of the invention provides a smoking substitute kit which may be used to deliver an aerosol vapour which is substantially flavourless, and so a user may use the kit in combination with their preferred flavour delivery mechanism. By providing a kit having a flavourless e-liquid in this way, product costs are reduced as only one e-liquid needs to be provided, which is suitable for use with all flavours which a user may desire.

Optionally, the smoking substitute kit may further comprise a flavour delivery article for delivering a smell and/or a flavour to a user. As the e-liquid provides a flavourless aerosol vapour, any suitable flavour delivery article may be used, and a user may choose their preferred flavour delivery article and flavour. This may allow the user to choose their own bespoke experience for the smoking substitute kit.

Advantageously, the flavour delivery article may comprise a scented substrate. Such a scented substrate permits heterogenous extraction of a flavour by the flavourless aerosol vapour of the vaporisable liquid. By storing the flavour (e.g. a flavourant) of the flavour delivery article in the solid state, the shelf-life of the flavour delivery article may be improved. Advantageously, the flavour delivery article may comprise a flavourant located on a surface of the smoking substitute apparatus. For example, in some embodiments, the flavour delivery article may comprise a sticker; wherein the sticker may comprise an adhesive portion for adhering the sticker to a surface of the smoking substitute apparatus; and a flavoured portion. The flavoured portion may comprise a scented substrate.

Advantageously, the scented substrate may comprise a disintegrant. As the substrate is in solid form, the extraction of embedded flavour compounds occurs most readily from the surface area of the substrate. Disintegrants, are agents added to solid formulations to promote the break-up of the formulation into smaller fragments. For example, certain disintegrants are activated by an aqueous environment, this causes the disintegrant to disintegrate, as disintegration occurs, the substrate may disaggregate into smaller fragments which therefore have an increased surface area. Consequently, the increased surface area permits an increased rate of flavour delivery.

Suitable disintegrants include starch-based disintegrants (such as from rice, wheat, corn or potato), microcrystalline cellulose, carmellose sodium, sodium carboxy-methylcellulose, cross-linked polyplasdone, croscarmellose, soy polysaccharides, sodium starch glycolate, and mixtures thereof. Preferably the disintegrant is starch based. In some embodiments, the substrate may comprise a carrier, which is itself a disintegrant. For example, a starch-based carrier (which is also a starch-based disintegrant).

Preferably, the scented substrate comprises from 1 wt% to 5 wt% of the disintegrant. For example, the scented substrate may comprise about 1 wt% disintegrant, about 2 wt% disintegrant, about 3 wt% disintegrant, about 4 wt% disintegrant, or about 5 wt% disintegrant. In some embodiments the scented substrate comprises from 1 .5 wt% to 4.5 wt% of the disintegrant. In some embodiments the scented substrate comprises from 2 wt% to 4 wt% of the disintegrant. In some embodiments the scented substrate comprises from 2 wt% to 3.5 wt% of the disintegrant. In some embodiments the scented substrate comprises from 2 wt% to 3 wt% of the disintegrant.

In some embodiments, the scented substrate is in the form of granules comprising an embedded flavourant. Granules have a large surface area and therefore promote the delivery of flavour. In the case that the granules comprise a disintegrant, then the surface area of the granules can be increased very efficiently by activation of the disintegrant thus promoting greater delivery of flavour.

Flavour delivery article/portion

The flavour delivery article may comprise a flavourant. The term “flavourant” is used to describe a compound or combination of compounds that provide flavour and/or aroma. For example, the flavourant may be configured to interact with a sensory receptor of a user (such as an olfactory or taste receptor). The flavourant may include one or more volatile substances.

The flavourant may be provided in solid or liquid form. The flavourant may be natural or synthetic. For example, the flavourant may include menthol, liquorice, chocolate, fruit flavour (including e.g. citrus, cherry etc.), vanilla, spice (e.g. ginger, cinnamon) and tobacco flavour. The flavourant may be evenly dispersed or may be provided in isolated locations and/or varying concentrations.

Smoking substitute apparatus

The smoking substitute apparatus may be in the form of a consumable. The consumable may be configured for engagement with a main body (i.e. so as to form a closed smoking substitute system). For example, the consumable may comprise components of the system that are disposable, and the main body may comprise non-disposable or non-consumable components (e.g. power supply, controller, sensor, etc.) that facilitate the delivery of aerosol by the consumable. In such an embodiment, the aerosol former (e.g. e-liquid) may be replenished by replacing a used consumable with an unused consumable.

Alternatively, the smoking substitute apparatus may be a non-consumable apparatus (e.g. that is in the form of an open smoking substitute system). In such embodiments an aerosol former (e.g. e-liquid) of the system may be replenished by re-filling e.g. a reservoir of the smoking substitute apparatus with the aerosol former (rather than replacing a consumable component of the apparatus).

In light of this, it should be appreciated that some of the features described herein as being part of the smoking substitute apparatus may alternatively form part of a main body for engagement with the smoking substitute apparatus (i.e. when the smoking substitute apparatus is in the form of a consumable).

Consumable/Main body engagement

Where the smoking substitute apparatus is in the form of a consumable, the main body and the consumable may be configured to be physically coupled together. For example, the consumable may be at least partially received in a recess of the main body, such that there is an interference fit between the main body and the consumable. Alternatively, the main body and the consumable may be physically coupled together by screwing one onto the other, or through a bayonet fitting.

Thus, the smoking substitute apparatus may comprise one or more engagement portions for engaging with a main body. In this way, one end of the smoking substitute apparatus may be coupled with the main body, whilst an opposing end of the smoking substitute apparatus may define a mouthpiece of the smoking substitute system.

Reservoir and e-liquid

The smoking substitute apparatus may comprise a reservoir configured to store an aerosol former, such as the e-liquid. The reservoir may be in the form of a tank. At least a portion of the tank may be translucent. For example, the tank may comprise a window to allow a user to visually assess the quantity of e-liquid in the tank. A housing of the smoking substitute apparatus may comprise a corresponding aperture (or slot) or window that may be aligned with a translucent portion (e.g. window) of the tank. The reservoir may be referred to as a “clearomizer” if it includes a window, or a “cartomizer” if it does not. Passage

The smoking substitute apparatus may comprise a passage for fluid flow therethrough. The passage may extend through (at least a portion of) the smoking substitute apparatus, between openings that may define an inlet and an outlet of the passage. The outlet may be at a mouthpiece of the smoking substitute apparatus. In this respect, a user may draw fluid (e.g. air) into and through the passage by inhaling at the outlet (i.e. using the mouthpiece). The passage may be at least partially defined by the tank. The tank may substantially (or fully) define the passage. In this respect, the tank may surround the passage.

Aerosol generator (Wick and heater)

The smoking substitute apparatus may comprise an aerosol-generator. The aerosol generator may comprise a wick. The aerosol generator may further comprise a heater. The wick may comprise a porous material. A portion of the wick may be exposed to fluid flow in the passage. The wick may also comprise one or more portions in contact with liguid stored in the reservoir. For example, opposing ends of the wick may protrude into the reservoir and a central portion (between the ends) may extend across the passage so as to be exposed to fluid flow in the passage. Thus, fluid may be drawn (e.g. by capillary action) along the wick, from the reservoir to the exposed portion of the wick.

The heater may comprise a heating element, which may be in the form of a filament wound about the wick (e.g. the filament may extend helically about the wick). The filament may be wound about the exposed portion of the wick. The heating element may be electrically connected (or connectable) to a power source. Thus, in operation, the power source may supply electricity to (i.e. apply a voltage across) the heating element so as to heat the heating element. This may cause liguid stored in the wick (i.e. drawn from the tank) to be heated so as to form a vapour and become entrained in fluid flowing through the passage. This vapour may subseguently cool to form an aerosol in the passage.

Power Source and Electrical interface

The smoking substitute apparatus (or main body engaged with the smoking substitute apparatus) may comprise a power source. The power source may be electrically connected (or connectable) to a heater of the smoking substitute apparatus (e.g. when engaged with the main body). The power source may be a battery (e.g. a rechargeable battery). A connector in the form of e.g. a USB port may be provided for recharging this battery.

When the smoking substitute apparatus is in the form of a consumable, the smoking substitute apparatus may comprise an electrical interface for interfacing with a corresponding electrical interface of the main body. One or both of the electrical interfaces may include one or more electrical contacts. Thus, when the main body is engaged with the consumable, the electrical interface may be configured to transfer electrical power from the power source to a heater of the consumable.

The electrical interface may also be used to identify the smoking substitute apparatus (in the form of a consumable) from a list of known types. For example, the consumable may have a certain concentration of nicotine and the electrical interface may be used to identify this. The electrical interface may additionally or alternatively be used to identify when a consumable is connected to the main body.

Again, where the smoking substitute apparatus is in the form of a consumable, the main body may comprise an interface, which may, for example, be in the form of an RFID reader, a barcode or QR code reader. This interface may be able to identify a characteristic (e.g. a type) of a consumable engaged with the main body. In this respect, the consumable may include any one or more of an RFID chip, a barcode or QR code, or memory within which is an identifier and which can be interrogated via the interface.

Controller, Sensor, Wireless Interface

The smoking substitute apparatus or main body may comprise a controller, which may include a microprocessor. The controller may be configured to control the supply of power from the power source to the heater of the smoking substitute apparatus (e.g. via the electrical contacts). A memory may be provided and may be operatively connected to the controller. The memory may include non-volatile memory. The memory may include instructions which, when implemented, cause the controller to perform certain tasks or steps of a method.

The main body or smoking substitute apparatus may comprise a wireless interface, which may be configured to communicate wirelessly with another device, for example a mobile device, e.g. via Bluetooth®. To this end, the wireless interface could include a Bluetooth® antenna. Other wireless communication interfaces, e.g. WiFi®, are also possible. The wireless interface may also be configured to communicate wirelessly with a remote server.

A puff sensor may be provided that is configured to detect a puff (i.e. inhalation from a user). The puff sensor may be operatively connected to the controller so as to be able to provide a signal to the controller that is indicative of a puff state (i.e. puffing or not puffing). The puff sensor may, for example, be in the form of a pressure sensor or an acoustic sensor. That is, the controller may control power supply to the heater of the consumable in response to a puff detection by the sensor. The control may be in the form of activation of the heater in response to a detected puff. That is, the smoking substitute apparatus may be configured to be activated when a puff is detected by the puff sensor. When the smoking substitute apparatus is in the form of a consumable, the puff sensor may form part of the consumable or the main body.

The invention includes the combination of the aspects and preferred features described except where such a combination is clearly impermissible or expressly avoided.

Summary of the Figures

So that the invention may be understood, and so that further aspects and features thereof may be appreciated, embodiments illustrating the principles of the invention will now be discussed in further detail with reference to the accompanying figures, in which: Figure 1A is a front view of a smoking substitute system, according to a first embodiment, in an engaged position;

Figure 1 B is a front view of the smoking substitute system of the first embodiment in a disengaged position;

Figure 1C is a section view of a smoking substitute apparatus of the first embodiment.

Detailed Description of the Invention

Aspects and embodiments of the present invention will now be discussed with reference to the accompanying figures. Further aspects and embodiments will be apparent to those skilled in the art. All documents mentioned in this text are incorporated herein by reference.

Figures 1A and 1 B illustrate a smoking substitute system in the form of an e-cigarette system 101. The system 101 comprises an e-cigarette device defining a main body 102 of the system 101 , and a smoking substitute apparatus in the form of an e-cigarette consumable (or “pod”) 103. In the illustrated embodiment the consumable 103 (smoking substitute apparatus) is removable from the main body (e-cigarette device), so as to be a replaceable component of the system 101 . In other words, the e-cigarette system 101 is a closed system.

As is apparent from Figures 1A and 1 B, the consumable 103 is configured to engage the main body 102. Figure 1 A shows the main body 102 and the consumable 103 in an engaged state, whilst Figure 1 B shows the main body 102 and the consumable 103 in a disengaged state. When engaged, a portion of the consumable 103 is received in a cavity of the main body 102 and is retained in the engaged position by way of a snap-engagement mechanism. In other embodiments, the main body 102 and consumable 103 may be engaged by screwing one into (or onto) the other, through a bayonet fitting, or by way of an interference fit.

The system 101 is configured to vaporise an aerosol-former, which in the illustrated embodiment, is in the form of e-liquid 104. The e-liquid 104 comprises propylene glycol, vegetable glycerine in a mass ratio of at least 30:70, and less than 5 wt% water. In some embodiments, the ratio of propylene glycol to vegetable glycerine is 60:40. In other embodiments, the ratio of propylene glycol to vegetable glycerine is 35:65. In the present embodiment, the e-liquid 104 is flavourless (and does not include any added flavourant). That is, if the e-liquid 104 were to be inhaled (i.e. in aerosol form) by a user, it would not have a particularly perceptible flavour or taste. In some examples, the e-liquid may further comprise nicotine. For example, the e-liquid 104 may comprise 5% or less by mass nicotine, wherein the total mass of vegetable glycerine, propylene glycol and nicotine is 100%.

As is more apparent from Figure 1C, this e-liquid 104 is stored within a reservoir in the form of a tank 105 that forms part of the consumable 103. In the illustrated embodiment, the consumable 103 is a “singleuse” consumable 103. That is, upon exhausting the e-liquid 104 in the tank 105, the intention is that the user disposes of the entire consumable 103. In other embodiments, the e-liquid (i.e. aerosol former) may be the only part of the system that is truly “single-use”. That is, the tank may be refillable with e-liquid or the e-liquid may be stored in a non-consumable component of the system. For example, the e-liquid may be stored in a tank located in the main body or stored in another component that is itself not single-use (e.g. a refillable cartomizer).

The tank 105 surrounds, and thus defines a portion of, a passage 106 that extends between an inlet 107 and an outlet 108 at opposing ends of the consumable 103. In this respect, the passage comprises an upstream end at the end of the consumable 103 that engages with the main body 102, and a downstream end at an opposing end of the consumable 103 that comprises a mouthpiece 109 of the system 101. When the consumable 103 is engaged with the main body 102, a user can inhale (i.e. take a puff) via the mouthpiece 109 so as to draw air through the passage 106, and so as to form an airflow (indicated by arrows) in a direction from the inlet 107 to the outlet 108 of the passage 106. Although not illustrated, the passage 106 may be partially defined by a tube (e.g. a metal tube) extending through the consumable 103. The passage 106 is in fluid communication with a gap defined between the consumable 103 and the main body 102 (when engaged) such that air outside of the system 101 is drawn into the passage 106 (during an inhale).

The smoking substitute system 101 is configured to vaporise the e-liquid 104 for inhalation by a user. To provide this, the consumable 103 comprises a heater having of a porous wick 110 and a resistive heating element in the form of a heating filament 111 that is helically wound around a portion of the porous wick 110. The porous wick 110 extends across the passage 106 (i.e. transverse to a longitudinal axis of the passage106) and opposing ends of the wick 110 extend into the tank 105 (so as to be submerged in the e-liquid 104). In this way, e-liquid 104 contained in the tank 105 is conveyed from the opposing ends of the porous wick 110 to a central portion of the porous wick 110 so as to be exposed to the airflow in the passage 106 (i.e. caused by a user inhaling). Vegetable glycerine is absorbed into the wick 110 at a slower rate than propylene glycol. As the e-liquid 110 is provided in a ratio of at least 30 parts propylene glycol to 70 parts vegetable glycerin; for example, 60 parts propylene glycol to 40 parts vegetable glycerine, or 35 parts propylene glycol to 65 parts vegetable glycerine; a good rate of absorption into the wick 110 is obtained, providing good operation of the smoking substitute system 101.

The helical filament 111 is wound about this exposed central portion of the porous wick 110 and is electrically connected to an electrical interface in the form of electrical contacts 112 mounted at the end of the consumable that is proximate the main body 102 (when engaged). When the consumable 103 is engaged with the main body 102, the electrical contacts 112 contact corresponding electrical contacts (not shown) of the main body 102. The main body electrical contacts are electrically connected to a power source (not shown) of the main body 102, such that (in the engaged position) the filament 111 is electrically connected to the power source. In this way, power can be supplied by the main body 102 to the filament 111 in order to heat the filament 111. This heat is transferred from the filament 111 to the porous wick 110 which causes e-liquid 104 conveyed by the porous wick 110 to increase in temperature to a point at which it vaporises. In particular, the vapour temperature of vegetable glycerine is lower than that of propylene glycol, and so by providing the e-liquid 110 as a mixture which comprises VG the mixture is easierto vaporise. This may help prolong battery life of the smoking substitute system 101 , for example, by requiring a lower power output to effect vaporisation. The vaporised e-liquid becomes entrained in the airflow and, between the vaporisation point at the filament 111 and the outlet 108 of the passage 106, condenses to form an aerosol. This aerosol is then inhaled, via the mouthpiece 109, by a user of the system 101.

The power source of the main body 102 may be in the form of a battery (e.g. a rechargeable battery). The main body 102 may comprise a connector in the form of e.g. a USB port for recharging this battery. The main body 102 may also comprise a controller that controls the supply of power from the power source to the main body electrical contacts (and thus to the filament 111). That, is the controller may be configured to control a voltage applied across the main body electrical contacts, and thus the voltage applied across the filament 111. In this way, the filament 111 may only be heated under certain conditions (e.g. during a puff and/or only when the system is in an active state). In this respect, the main body 102 may include a puff sensor (not shown) that is configured to detect a puff (i.e. inhalation). The puff sensor may be operatively connected to the controller so as to be able to provide a signal, to the controller, which is indicative of a puff state (i.e. puffing or not puffing). The puff sensor may, for example, be in the form of a pressure sensor or an acoustic sensor.

Although not shown, the main body 102 and consumable 103 may comprise a further interface which may, for example, be in the form of an RFID reader, a barcode or QR code reader. This interface may be able to identify a characteristic (e.g. a type) of a consumable 103 engaged with the main body 102. In this respect, the consumable 103 may include any one or more of an RFID chip, a barcode or QR code, or memory within which is an identifier and which can be interrogated via the interface.

In some examples, the smoking substitute system 101 may be provided with a flavour delivery article for delivering a smell and/or a flavour to a user. For example, as shown in Figs. 1A and 1 B, a sticker 120 may be affixed to the mouthpiece 109 of the consumable 103, such that the sticker 120 covers the outlet 108 of the mouthpiece 109. The sticker 120 includes an adhesive portion which serves to adhere the sticker 120 to the mouthpiece 109, and a flavoured portion which is arranged to cover the outlet 108 of the mouthpiece 109. The flavoured portion of the sticker 120 is permeable to the aerosol generated in the apparatus 101 , such that the aerosol may pass through the flavoured portion of the sticker 120 when a user inhales the aerosol through the mouthpiece 109.

The flavoured portion of the sticker 120 includes a flavourant which may be entrained by the aerosol when the aerosol passes through the flavoured portion of the sticker 120, to provide flavour to the user. The flavourant may also produce a taste on the user’s tongue when the user puts the mouthpiece 109 in their mouth. In this manner, flavour may be delivered to the user without having to include any flavourant in the e-liquid, in particular by providing an e-liquid which comprises vegetable glycerine, propylene glycol, and water, wherein the e-liquid comprises less than 5 wt% water, and the ratio by mass of propylene glycol to vegetable glycerin is at least 30:70. This means that a single e-liquid 110 may be manufactured to be used with a large number of smoking substitute devices and flavours, which reduces the cost of the e-liquid 110. Of course, any other suitable flavour delivery articles may be considered in accordance with the present invention. The flavoured portion of the sticker 120 may comprise a substrate, such as granules, which comprise a disintegrant. In use, initially large granules come into contact with aerosol generated from the e-liquid and the disintegrant is activated, e.g., by the presence of water in the vapour. Activation begins the process of disintegration in which the large granules form smaller granules, exposing an increased surface area through which flavourant may be delivered from the substrate, to the aerosol stream and ultimately to the user. Further activation of the disintegrant can be performed by subsequent contact of aerosol with the substrate, until complete disaggregation has occurred and negligible flavourant remains in the granules, at which point the sticker 120 may be considered spent.

The features disclosed in the foregoing description, or in the following claims, or in the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for obtaining the disclosed results, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

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 when given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.

For the avoidance of any doubt, any theoretical explanations provided herein are provided for the purposes of improving the understanding of a reader. The inventors do not wish to be bound by any of these theoretical explanations.

Any section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.

Throughout this specification, including the claims which follow, unless the context requires otherwise, the words “have”, “comprise”, and “include”, and variations such as “having”, “comprises”, “comprising”, and “including” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by the use of the antecedent “about,” it will be understood that the particular value forms another embodiment. The term “about” in relation to a numerical value is optional and means, for example, +/- 10%.

The words "preferred" and "preferably" are used herein refer to embodiments of the invention that may provide certain benefits under some circumstances. It is to be appreciated, however, that other embodiments may also be preferred under the same or different circumstances. The recitation of one or more preferred embodiments therefore does not mean or imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, or from the scope of the claims.

Claims

Claims:

1 . A vaporisable liquid for a smoking substitute apparatus, the vaporisable liquid comprising: vegetable glycerine, propylene glycol, and water; wherein: the vaporisable liquid comprises less than 5 wt% water; and the ratio by mass of propylene glycol to vegetable glycerine is at least 30:70.

2. A vaporisable liquid according to claim 1 , comprising between 0.25 wt% and 5 wt% water.

3. A vaporisable liquid according to claim 1 or claim 2, wherein the ratio by mass of propylene glycol to vegetable glycerine is at least 60:40.

4. A vaporisable liquid according to claim 1 , wherein the ratio by mass of propylene glycol to vegetable glycerine is between 30:70 and 40:60.

5. A vaporisable liquid according to claim 4, wherein the ratio by mass of propylene glycol to vegetable glycerine is 35:65.

6. A vaporisable liquid according to claim 4 or claim 5, wherein the vaporisable liquid comprises less than 0.25% water.

7. A vaporisable liquid according to any one of the preceding claims, further comprising nicotine.

8. A vaporisable liquid according to claim 7, wherein the vaporisable liquid comprises 5% or less by mass nicotine, wherein the total mass of vegetable glycerine, propylene glycol, water and nicotine is 100%.

9. A smoking substitute kit comprising: a vaporisable liquid according to any one of the preceding claims; and a smoking substitute apparatus for generating an aerosol from the vaporisable liquid.

10. A smoking substitute kit according to claim 9, further comprising a flavour delivery article for delivering a smell and/or a flavour to a user.

11 . A smoking substitute kit according to claim 10, wherein the flavour delivery article comprises a scented substrate.

12. A smoking substitute kit according to claim 10 or claim 11 , wherein the flavour delivery article comprises a sticker; the sticker comprising: an adhesive portion for adhering the sticker to a surface of the smoking substitute apparatus; and a flavoured portion having a scented substrate.

13. A smoking substitute kit according to claim 11 or claim 12, wherein the scented substrate comprises a disintegrant.

14. A smoking substitute kit according to claim 13, wherein the scented substrate comprises from 1 wt% to 5 wt% of the disintegrant.

15. A smoking substitute kit according to any one of claims 11 to 14, wherein the scented substrate is in the form of granules comprising embedded flavourant.