EP3873256A1

EP3873256A1 - Smoking substitute consumable

Info

Publication number: EP3873256A1
Application number: EP19798009.7A
Authority: EP
Inventors: Chris Lord; Kate FERRIE; Edward Ross SHENTON
Original assignee: Nerudia Ltd
Current assignee: IMPERIAL TOBACCO Ltd
Priority date: 2018-10-29
Filing date: 2019-10-25
Publication date: 2021-09-08
Also published as: WO2020089115A1

Abstract

The present disclosure relates to an aerosol-forming article comprising an aerosol-forming substrate and a solid filter element wherein the article comprises at least one radial air flow path into the filter element. The present disclosure also relates to an aerosol-forming article comprising an aerosol-forming substrate and a hollow bore filter element wherein the article comprises at least one radial air flow path into the hollow bore filter element.

Description

Smoking substitute consumable

This patent application claims priority from UK patent application numbers GB1817567.9 and GB1817580.2 filed on 29 October 2019, the content of which is incorporated herein.

Field of the Disclosure

The present disclosure relates to a consumable for use in a smoking substitute system and particularly, although not exclusively, to a heat-not-burn (HNB) consumable.

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.

Conventional combustible smoking articles, such as cigarettes, typically comprise a cylindrical rod of tobacco comprising shreds of tobacco which is surrounded by a wrapper, and usually also a cylindrical filter axially aligned in an abutting relationship with the wrapped tobacco rod. The filter typically comprises a filtration material which is circumscribed by a plug wrap. The wrapped tobacco rod and the filter are joined together by a wrapped band of tipping paper that circumscribes the entire length of the filter and an adjacent portion of the wrapped tobacco rod. A conventional cigarette of this type is used by lighting the end opposite to the filter, and burning the tobacco rod. The smoker receives mainstream smoke into their mouth by drawing on the mouth end or filter end of the cigarette.

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 (or“substitute smoking 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 flavourings 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. Some smoking substitute systems use smoking substitute articles that are designed to resemble a traditional cigarette and are cylindrical in form with a mouthpiece at one end.

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 for a smoking substitute system is the so-called "heat not burn" (“HNB”) approach in which tobacco (rather than an "e-liquid”) is heated or warmed to release vapour. The tobacco may be leaf tobacco or reconstituted tobacco. The vapour may contain nicotine and/or flavourings. In the HNB approach the intention is that the tobacco is heated but not burned, i.e. the tobacco does not undergo combustion.

A typical HNB smoking substitute system may include a device and a consumable. The consumable may include the tobacco material. The device and consumable may be configured to be physically coupled together. In use, heat may be imparted to the tobacco material by a heating element of the device, wherein airflow through the tobacco material causes moisture in the tobacco material to be released as vapour. A vapour may also be formed from a carrier in the tobacco material (this carrier may for example include propylene glycol and/or vegetable glycerine) and additionally volatile compounds released from the tobacco. The released vapour may be entrained in the airflow drawn through the tobacco.

As the vapour passes through the consumable (entrained in the airflow) from an inlet to a mouthpiece (outlet), the vapour cools and condenses to form an aerosol for inhalation by the user. The aerosol will normally contain the volatile compounds.

In HNB smoking substitute systems, heating as opposed to burning the tobacco material is believed to cause fewer, or smaller quantities, of the more harmful compounds ordinarily produced during smoking. Consequently, the HNB approach may reduce the odour and/or health risks that can arise through the burning, combustion and pyrolytic degradation of tobacco.

There is a need for improved design of HNB consumables to enhance the user experience and improve the function of the HNB smoking substitute system.

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

At its most general, the present disclosure relates to an aerosol-forming article e.g. a smoking substitute article such as an HNB consumable having an air flow path into the consumable upstream of a terminal filter element.

According to a first aspect, there is provided an aerosol-forming article (e.g. a smoking substitute article such as an HNB consumable) comprising an aerosol-forming substrate and a filter element wherein the article comprises at least one radial air flow path into the filter element.

By providing at least one radial air flow path into a filter element, air can be drawn into the aerosol-forming substrate as the user inhales and this air can help to cool and mix the vapour. The cross-sectional area of the at least one airflow path and/or the number of radial air flow paths can be tailored to tailor the resistance to draw (RTD) of the article/consumable.

Optional features will now be set out. These are applicable singly or in any combination with any aspect. The aerosol-forming article of the first aspect is preferably a heat-not-burn (HNB) consumable.

The filter element is preferably a solid filter element i.e. with no axial bore.

In some embodiments, there is a plurality of radial air flow paths which may be circumferentially-arranged around the filter element. There may be a plurality of axially spaced, circumferentially-extending rows of radial flow paths.

The radial air flow path(s) may be provided in a terminal filter element at the downstream axial end of the article/consumable and/or in an upstream filter element provided upstream from the downstream axial end of the article/consumable and downstream (e.g. adjacent the downstream axial end) of the aerosol-forming substrate.

According to a second aspect, there is provided an aerosol-forming article (e.g. a smoking substitute article such as an HNB consumable) comprising an aerosol-forming substrate and a hollow bore filter element wherein the article comprises at least one radial air flow path into the hollow bore filter element.

By providing at least one radial air flow path into a hollow bore filter element, air can be drawn into the aerosol-forming substrate as the user inhales and this air can help to cool and mix the vapour. The cross- sectional area of the at least one air flow path and/or the number of radial air flow paths can be tailored to tailor the resistance to draw (RTD) of the article/consumable. Further optional features will now be set out. These are applicable singly or in any combination with any aspect.

The aerosol-forming article of the second aspect is preferably a heat-not-burn (HNB) consumable.

In some embodiments, there is a plurality of radial air flow paths which may be circumferentially-arranged around the hollow bore filter element. There may be a plurality of axially spaced, circumferentially- extending rows of radial flow paths.

The radial air flow path(s) may be provided in a terminal hollow bore filter element at the downstream axial end of the article/consumable and/or in an upstream hollow bore filter element provided upstream from the downstream axial end of the article/consumable and downstream (e.g. adjacent the downstream axial end) of the aerosol-forming substrate.

As used herein, the terms’’upstream” and“downstream” are intended to refer to the flow direction of the vapour/aerosol i.e. with the downstream end of the article/consumable being the mouth end or outlet where the aerosol exits the article/consumable for inhalation by the user. The upstream end of the article/consumable is the opposing end to the downstream end. The axial direction of the article/consumable is aligned with the flow direction of the vapour/aerosol i.e. extends between the upstream and downstream ends of the article/consumable. The radial air flow path(s) extend(s) substantially perpendicularly to the axial direction/flow direction of the vapour/aerosol.

Where the radial air flow path(s) is/are provided in a terminal filter element or a terminal hollow bore filter element, the article/consumable may further comprise an upstream filter element which may be a hollow bore filter element comprising a further at least one radial air flow path (as described above), a hollow bore filter element with no radial flow path or a solid filter element.

Where the radial airflow path(s) is/are provided in an upstream filter element (e.g. adjacent the downstream axial end of the aerosol-forming substrate), the article/consumable may further comprise a terminal filter element which may be a hollow bore filter element comprising a further at least one radial air flow path (as described above), a hollow bore filter element with no radial flow path or a solid filter element.

In some embodiments, the article/consumable may further comprise a spacer element or an aerosol-cooling element upstream and axially adjacent the terminal filter element. The spacer/aerosol-cooling element may be interposed between the upstream filter element and the terminal filter element, e.g. between the upstream hollow bore filter element and the terminal hollow bore filter element. The aerosol-forming substrate may be circumscribed by a wrapping layer e.g. a paper wrapping layer. The wrapping layer may overlie an inner foil layer or may comprise a paper/foil laminate (with the foil innermost).

The spacer/aerosol-cooling element may be at least partly (e.g. entirely) circumscribed by the (paper) wrapping layer. The upstream filter element (e.g. the upstream filter element) may be at least partly (e.g. entirely) circumscribed by the (paper) wrapping layer.

The radial air flow path(s) may be provided by one or more ventilation holes provided in the wrapping layer surrounding the upstream filter element. There may be a plurality of ventilation holes circumferentially arranged around the upstream filter element e.g. a plurality of axially spaced, circumferentially-extending rows of ventilation holes.

The terminal filter element may be joined to the upstream elements forming the article/consumable (e.g. the upstream filter element and/or the spacer/aerosol-cooling element) by a circumscribing tipping layer e.g. a tipping paper layer. The tipping paper may have an axial length longer than the axial length of the terminal filter element such that the tipping paper completely circumscribes the terminal filter element plus the wrapping layer surrounding any adjacent upstream element (e.g. the adjacent spacer element or aerosol-cooling element).

The radial air flow path(s) may be provided by one or more ventilation holes provided in the tipping layer surrounding the terminal filter element. There may be a plurality of ventilation holes circumferentially arranged around the terminal filter element e.g. a plurality of axially spaced, circumferentially-extending rows of ventilation holes.

The radial air flow path(s) may be provided by one or more radial bores provided in the upstream filter element and/or the terminal filter element. There may be a plurality of radial bores circumferentially arranged around the upstream filter element and/or the terminal filter element e.g. a plurality of axially spaced, circumferentially-extending rows of radial bores.

The radial air flow path(s) may be provided by one or more ventilation holes provided in the tipping layer surrounding the terminal hollow bore filter element. There may be a plurality of ventilation holes circumferentially arranged around the terminal hollow bore filter element e.g. a plurality of axially spaced, circumferentially-extending rows of ventilation holes.

The radial air flow path(s) may be provided by one or more radial bores provided in the upstream hollow bore filter element and/or the terminal hollow bore filter element. There may be a plurality of radial bores circumferentially arranged around the upstream hollow bore filter element and/or the terminal hollow bore filter element e.g. a plurality of axially spaced, circumferentially-extending rows of radial bores. The radial bore(s) may extend through the terminal/upstream filter element and join the axial bore of the terminal/upstream filter element.

The radial bore(s) in the upstream filter element may be aligned or overlapping with the ventilation hole(s) in the wrapping layer.

The radial bore(s) in the terminal filter element may be aligned or overlapping with the ventilation hole(s) in the tipping layer.

The radial bore(s) in the terminal hollow filter element may be aligned or overlapping with the ventilation hole(s) in the tipping layer.

The or each filter element is formed of a smoke-permeable material. The terminal and/or upstream filter element(s) may be comprised of cellulose acetate or polypropylene tow. The terminal and/or upstream filter element(s) may be comprised of activated charcoal. The terminal and/or upstream filter element(s) may be comprised of paper. The terminal and/or upstream filter element(s) may each be circumscribed with a respective plug wrap e.g. a paper plug wrap.

The radial air flow path(s) may be provided by one or more ventilation holes provided in the respective plug wrap circumscribing the upstream filter element and/or the terminal filter element. There may be a plurality of ventilation holes in the plug wrap(s) circumferentially arranged around the upstream filter element and/or the terminal filter element e.g. a plurality of axially spaced, circumferentially-extending rows of ventilation holes.

The radial bore(s) in the upstream hollow filter element may be aligned or overlapping with the ventilation hole(s) in the upstream filter element plug wrap.

The radial bore(s) in the terminal hollow filter element may be aligned or overlapping with the ventilation hole(s) in the downstream filter element plug wrap.

The radial air flow path(s) may be provided by one or more ventilation holes provided in the respective plug wrap circumscribing the upstream hollow bore filter element and/or the terminal hollow bore filter element. There may be a plurality of ventilation holes in the plug wrap(s) circumferentially arranged around the upstream hollow bore filter element and/or the terminal hollow bore filter element e.g. a plurality of axially spaced, circumferentially-extending rows of ventilation holes.

The radial bore(s) in the upstream hollow filter element may be aligned or overlapping with the ventilation hole(s) in the upstream filter element plug wrap. The radial bore(s) in the terminal hollow filter element may be aligned or overlapping with the ventilation hole(s) in the downstream filter element plug wrap.

The porosity of the upstream filter element may be greater than the porosity of the terminal filter element.

The terminal and/or upstream filter element(s) may each have a substantially cylindrical shape with a diameter substantially matching the diameter of the aerosol-forming substrate (with or without its associated wrapping layer). The axial length of the or each filter element may be less than 20mm, e.g. between 8 and 15mm, for example between 9 and 13 mm e.g. between 10 and 12mm.

The aerosol-cooling element is adapted to cool the aerosol generated from the aerosol-forming substrate (by heat exchange) before being inhaled by the user.

The hollow bore terminal filter element(s) may have a bore diameter of between 1 and 5 mm, e.g. between 2 and 4 mm or between 2 and 3 mm. The diameter of the axial bore in the upstream hollow bore filter element may be greater than the diameter of the axial bore in the terminal filter element.

The aerosol-cooling element may be formed of a plastics material selected from the group consisting of polylactic acid (PLA), polyvinyl chloride (PVC), polyethylene (PE) and polyethylene terephthalate (PET). The aerosol-cooling element may be formed of a crimped/gathered sheet of material to form a structure having a high surface area with a plurality of longitudinal channels to maximise heat exchange and cooling of the aerosol.

The spacer element defines a space or cavity or chamber between the aerosol-forming substrate and the downstream end of the article/consumable e.g. between the upstream and terminal filter elements. The spacer element acts to allow both cooling and mixing of the aerosol. The spacer element may have a tubular wall e.g. formed of cardboard.

The spacer element may have an external diameter of between 5 and 10mm e.g. between 6 and 9mm or 6 and 8mm e.g. around 7 mm. It may have an axial length of between 10 and 15mm e.g. between 12 and 14 mm or 13 and 14mm e.g. around 14mm.

The aerosol-forming substrate is capable of being heated to release at least one volatile compound that can form an aerosol. The aerosol-forming substrate may be located at the upstream end of the article/consumable.

In order to generate an aerosol, the aerosol-forming substrate comprises at least one volatile compound that is intended to be vaporised/aerosolised and that may provide the user with a recreational and/or medicinal effect when inhaled. Suitable chemical and/or physiologically active volatile compounds include the group consisting of: nicotine, cocaine, caffeine, opiates and opoids, cathine and cathinone, kavalactones, mysticin, beta-carboline alkaloids, salvinorin A together with any combinations, functional equivalents to, and/or synthetic alternatives of the foregoing.

The aerosol-forming substrate may comprise plant material. The plant material may comprise least one plant material selected from the list including Amaranthus dubius, Arctostaphylos uva-ursi (Bearberry), Argemone mexicana, Arnica, Artemisia vulgaris, Yellow Tees, Galea zacatechichi, Canavalia maritima (Baybean), Cecropia mexicana (Guamura), Oestrum noctumum, Cynogtossum virginianum (wild comfrey), Cytisus scoparius, Damiana, Entada rheedii, Eschscholzia califomica (California Poppy), Fittonia albivenis, Hippobroma longi flora, Humulus japonica (Japanese Hops), Humulus lupulus (Hops), Lactuca virosa (Lettuce Opium), Laggera alata, Leonotis leonurus, Leonurus cardiaca (Motherwort), Leonurus sibiricus (Honeyweed), Lobelia cardinalis, Lobelia inflata (Indian-tobacco), Lobelia siphilitica, Nepeta cataria (Catnip), Nicotiana species (Tobacco), Nymphaea alba (White Lily), Nymphaea caerulea (Blue Lily), Opium poppy, Passiflora incamata (Passionflower), Pedicularis densiflora (Indian Warrior), Pedicularis groenlandica (Elephant's Head), Salvia divinorum, Salvia dorrii (Tobacco Sage), Salvia species (Sage), Scutellaria galericulata, Scutellaria lateriflora, Scutellaria nana, Scutellaria species (Skullcap), Sida acuta (Wireweed), Sida rhombifolia, Silene capensis, Syzygium aromaticum (Clove), Tagetes lucida (Mexican Tarragon), Tarchonanthus camphoratus, Tumera diffusa (Damiana), Verbascum (Mullein), Zamia latifolia (Maconha Brava) together with any combinations, functional equivalents to, and/or synthetic alternatives of the foregoing.

Preferably, the plant material is tobacco. Any type of tobacco may be used. This includes, but is not limited to, flue-cured tobacco, burley tobacco, Maryland Tobacco, dark-air cured tobacco, oriental tobacco, dark-fired tobacco, perique tobacco and rustica tobacco. This also includes blends of the above mentioned tobaccos.

Any suitable parts of the tobacco plant may be used. This includes leaves, stems, roots, bark, seeds and flowers.

The tobacco may comprise one or more of leaf tobacco, stem tobacco, tobacco powder, tobacco dust, tobacco derivatives, expanded tobacco, homogenised tobacco, shredded tobacco, extruded tobacco, cut rag tobacco and/or reconstituted tobacco (e.g. slurry recon or paper recon).

The aerosol-forming substrate may comprise a gathered sheet of homogenised (e.g. paper/slurry recon) tobacco or gathered shreds/strips formed from such a sheet.

In some embodiments, the sheet used to form the aerosol-forming substrate has a grammage greater than or equal to 100 g/m², e.g. greater than or equal to 110 g/m² such as greater than or equal to 120 g/m². The sheet may have a grammage of less than or equal to 300 g/m² e.g. less than or equal to 250 g/m² or less than or equal to 200 g/m².

The sheet may have a grammage of between 120 and 190 g/m².

The aerosol-forming substrate may comprise at least 50 wt% plant material, e.g. at least 60 wt% plant material e.g. around 65 wt% plant material. The aerosol-forming substrate may comprise 80 wt% or less plant material e.g. 75 or 70 wt% or less plant material.

The aerosol-forming substrate may comprise one or more additives selected from humectants, flavourants, fillers, aqueous/non-aqueous solvents and binders.

Humectants are provided as vapour generators - the resulting vapour helps carry the volatile active compounds and increases visible vapour. Suitable humectants include polyhydric alcohols (e.g. propylene glycol (PG), triethylene glycol, 1 ,2-butane diol and vegetable glycerine (VG)) and their esters (e.g. glycerol mono-, di- or tri-acetate). They may be present in the aerosol-forming substrate in an amount between 1 and 50 wt%.

The humectant content of the aerosol-forming substrate may have a lower limit of at least 1 % by weight of the plant material, such as at least 2 wt %, such as at least 5 wt %, such as at least 10 wt %, such as at least 20 wt %, such as at least 30 wt %, or such as least 40 wt %.

The humectant content of the aerosol-forming substrate may have an upper limit of at most 50 % by weight of the plant material, such as at most 40 wt %, such as at most 30 wt %, or such as at most 20 wt %.

Preferably, the humectant content is 1 to 40 wt % of the aerosol-forming substrate, such as 1 to 20 wt %

Suitable binders are known in the art and may act to bind together the components forming the aerosolforming substrate. Binders may comprise starches and/or cellulosic binders such as methyl cellulose, ethyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose and methyl cellulose, gums such as xanthan, guar, arabic and/or locust bean gum, organic acids and their salts such as alginic acid/ sodium alginate, agar and pectins.

Preferably the binder content is 5 to 10 wt% of the aerosol-forming substrate e.g. around 6 to 8 wt%.

Suitable fillers are known in the art and may act to strengthen the aerosol-forming substrate. Fillers may comprise fibrous (non-tobacco) fillers such as cellulose fibres, lig nocellulose fibres (e.g. wood fibres), jute fibres and combinations thereof. Preferably, the filler content is 5 to 10 wt% of the aerosol-forming substrate e.g. around 6 to 9 wt%.

The aerosol-forming substrate may comprise an aqueous and/or non-aqueous solvent. In some embodiments, the aerosol forming substrate has a water content of between 5 and 10 wt% e.g. between 6-9 wt% such as between 7-9 wt%.

The flavourant may be provided in solid or liquid form. It 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 throughout the aerosol-forming substrate or may be provided in isolated locations and/or varying concentrations throughout the aerosol-forming substrate.

The aerosol-forming substrate may be formed in a substantially cylindrical shape such that the article/consumable resembles a conventional cigarette. It may have a diameter of between 5 and 10mm e.g. between 6 and 9mm or 6 and 8mm e.g. around 7 mm. It may have an axial length of between 10 and 15mm e.g. between 11 and 14mm such as around 12 or 13mm.

In a third aspect, there is provided a solid filter element for an aerosol-forming article (e.g. a smoking substitute article such as an HNB consumable), the solid filter element comprising at least one radial bore.

The term“solid filter element” is used to describe a filter element hot having an axial bore.

There may be a plurality of radial bores circumferentially arranged around the filter element e.g. a plurality of axially spaced, circumferentially-extending rows of radial bores.

In a fourth aspect, there is provided a filter element for an aerosol-forming article (e.g. a smoking substitute article such as an HNB consumable), the filter element comprising an axial bore and at least one radial bore.

There may be a plurality of radial bores circumferentially arranged around the hollow bore filter element e.g. a plurality of axially spaced, circumferentially-extending rows of radial bores. The radial bore(s) may extend through the filter element and join the axial bore of the filter element.

The filter element is formed of a smoke-permeable material. The filter element may be comprised of cellulose acetate or polypropylene tow. The filter element may be comprised of activated charcoal. The filter element may be comprised of paper.

The filter element may be circumscribed with a plug wrap e.g. a paper plug wrap. The plug wrap may comprise one or more ventilation holes. There may be a plurality of ventilation holes in the plug wrap circumferentially arranged around the filter element e.g. a plurality of axially spaced, circumferentially-extending rows of ventilation holes.

The radial bore(s) in the filter element may be aligned or overlapping with the ventilation hole(s) in the plug wrap.

The filter element may each have a substantially cylindrical shape. The axial length of the filter element may be less than 20mm, e.g. between 8 and 15mm, for example between 9 and 13 mm e.g. between 10 and 12mm.

In a fifth aspect, there is provided an aerosol-forming article (e.g. a smoking substitute article such as an HNB consumable) comprising at least one filter element according to the third aspect.

In a sixth aspect, there is provided an aerosol-forming article (e.g. a smoking substitute article such as an HNB consumable) comprising at least one filter element according to the fourth aspect.

In a seventh aspect, there is provided a smoking substitute system comprising an aerosol-forming article according to the first, second, fifth or sixth aspects and a device comprising a heating element.

The device may be a HNB device i.e. a device adapted to heat but not combust the aerosol-forming substrate.

The device may comprise a main body for housing the heating element. The heating element may comprise an elongated e.g. rod, tube-shaped or blade heating element. The heating element may project into or surround a cavity within the main body for receiving the article/consumable described above.

The device (e.g. the main body) may further comprise an electrical power supply e.g. a (rechargeable) battery for powering the heating element. It may further comprise a control unit to control the supply of power to the heating element.

In an eighth aspect, there is provided a method of using a smoking substitute system according to the seventh aspect, the method comprising:

inserting the article/consumable into the device; and

heating the article/consumable using the heating element.

In some embodiments, the method comprises inserting the article/consumable into a cavity within the main body and penetrating the article/consumable with the heating element upon insertion of the article/consumable. For example, the heating element may penetrate the aerosol-forming substrate in the article/consumable. The skilled person will appreciate that except where mutually exclusive, a feature or parameter described in relation to any one of the above aspects may be applied to any other aspect. Furthermore, except where mutually exclusive, any feature or parameter described herein may be applied to any aspect and/or combined with any other feature or parameter described herein.

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 1 shows a first embodiment of an HNB consumable;

Figure 2 shows a second embodiment of an HNB consumable;

Figure 3 shows a third embodiment of an HNB consumable;

Figure 4 shows the first embodiment within a device forming an HNB system;

Figure 5 shows a fourth embodiment of an HNB consumable;

Figure 6 shows a fifth embodiment of an HNB consumable;

Figure 7 shows a sixth embodiment of an HNB consumable; and

Figure 8 shows the fourth embodiment within a device forming an HNB system.

Detailed Description of the Figures

As shown in Figure 1 , the HNB consumable 1 comprises an aerosol-forming substrate 2 at the upstream end of the consumable 1.

The aerosol-forming substrate comprises reconstituted tobacco which includes nicotine as a volatile compound.

The aerosol-forming substrate 2 comprises 65 wt% tobacco which is provided in the form of gathered shreds produced from a sheet of slurry/paper recon tobacco. The tobacco is dosed with 20wt% of a humectant such as propylene glycol (PG) or vegetable glycerine (VG) and has a moisture content of between 7-9 wt%. The aerosol-forming substrate further comprises cellulose pulp filler and guar gum binder. The aerosol-forming substrate 2 is formed in a substantially cylindrical shape such that the consumable resembles a conventional cigarette. It has diameter of around 7mm and an axial length of around 12 mm.

The aerosol-forming substrate 2 is circumscribed by a paper wrapping layer 3.

The consumable 1 comprises an upstream filter element 4 and a downstream (terminal) filter element 5. The two filter elements 4, 5 and spaced by a cardboard tube spacer 6. Both filter elements 4, 5 are formed of cellulose acetate tow and wrapped with a respective paper plug layer (not shown).

Both filter elements have a substantially cylindrical shape. The diameter of the upstream filter 4 matches the diameter of the aerosol-forming substrate 2. The diameter of the terminal filter element 5 is slightly larger and matches the combined diameter of the aerosol-forming substrate 2 and the wrapping layer 3. The upstream filter element is slightly shorter in axial length than the terminal filter element at an axial length of 10mm compared to 12mm for the terminal filter element.

The cardboard tube spacer is longer than each of the two filter elements having an axial length of around 14mm.

The upstream filter element 4 is hollow bore filter element with a hollow, longitudinally-extending axial bore. The diameter of the axial bore in the upstream filter 4 is 3 mm.

The cardboard tube spacer 6 and the upstream filter element 4 are circumscribed by the wrapping layer 3.

The terminal filter element 5 is joined to the upstream elements forming the consumable by a circumscribing paper tipping layer 7. The tipping layer 7 encircles the terminal filter element 5 and has an axial length of around 20mm such that it overlays a portion of the cardboard tube spacer 6.

A plurality of radial air flow paths are provided by a first circumferentially-extending row of ventilation holes 13a, 13b and an axially spaced second circumferentially-extending row of ventilation holes 14a, 14b in the tipping layer 7 which are circumferentially arranged around the terminal filter element 5.

Figure 2 shows a second embodiment of a consumable 1 which is the same as the first embodiment except that the upstream filter element 4 is a solid filter element and incudes a crushball 8 which contains a flavourant. Furthermore, the ventilation holes 13a, 13b, 14a, 14b extend through the tipping layer 7 and are aligned with radial bores 15a, 15b, 16a, 16b extending into the terminal filter element 5. Of course, the upstream filter element could be replaced with a hollow bore filter element as shown in Figure 1.

Figure 3 shows a third embodiment of a consumable 1 which is the same as the first embodiment except that the wrapping layer 3 does not completely circumscribe the cardboard tube spacer 6 such that there is an annular gap 9 between the tipping layer 7 and the cardboard tube spacer 6 downstream of the end of the wrapping layer 3. Furthermore, the ventilation holes are provided in the upstream filter element 4 with a first row of ventilation holes 13a, 13b extend through the wrapping layer 3 and through the upstream filter element 4 into the hollow bore of the terminal filter element 4 whilst the second row of ventilation holes 14a, 14b extending only through the wrapping layer 3.

Figure 4 shows the first embodiment inserted into an HNB device 10 comprising a rod-shaped heating element 20. The heating element 20 projects into a cavity 11 within the main body 12 of the device.

The consumable 1 is inserted into the cavity 11 of the main body 12 of the device 10 such that the heating rod 20 penetrates the aerosol-forming substrate 2. Heating of the reconstituted tobacco in the aerosolforming substrate 2 is effected by powering the heating element (e g. with a rechargeable battery (not shown)). As the tobacco is heated, moisture and volatile compound (e.g. nicotine) within the tobacco and the humectant are released as a vapour and entrained within an airflow generated by inhalation by the user at the terminal filter element 5.

As the vapour cools within the upstream filter element 4 and the cardboard tube spacer 6, it condenses to form an aerosol containing the volatile compounds for inhalation by the user.

Inhalation by the user also draws in air along the radial flow paths through the ventilation holes 13a, 13b, 14a, 14b. This air helps to mix and cool the vapour.

Turning now to consider Figure 5, there is shown a fourth embodiment of an HNB consumable 1 comprising an aerosol-forming substrate 2 at the upstream end of the consumable 1.

The aerosol-forming substrate 2 comprises 65 wt% tobacco which is provided in the form of gathered shreds produced from a sheet of slurry/paper recon tobacco. The tobacco is dosed with 20wt% of a humectant such as propylene glycol (PG) or vegetable glycerine (VG) and has a moisture content of between 7-9 wt%. The aerosol-forming substrate further comprises cellulose pulp filler and guar gum binder.

The aerosol-forming substrate 2 is formed in a substantially cylindrical shape such that the consumable resembles a conventional cigarette. It has diameter of around 7mm and an axial length of around 12 mm.

The aerosol-forming substrate 2 is circumscribed by a paper wrapping layer 3. The consumable 1 comprises an upstream filter element 4 and a downstream (terminal) filter element 5. The two filter elements 4, 5 and spaced by a cardboard tube spacer 6. Both filter elements 4, 5 are formed of cellulose acetate tow and wrapped with a respective paper plug layer (not shown).

In this embodiment, both filter elements 4, 5 are hollow bore filter elements with a hollow, longitudinally- extending axial bore. The diameter of the axial bore in the upstream filter 4 is slightly larger than the diameter of the axial bore in the terminal filter element 5 having a diameter of 3mm compared to 2 mm for the terminal filter element.

Figure 6 shows a fifth embodiment of a consumable 1 which is the same as the fourth embodiment except that the upstream filter element 4 is a solid filter element and incudes a crushball 8 which contains a flavourant. Furthermore, the ventilation holes 13a, 13b, 14a, 14b extend through the tipping layer 7 and are aligned with radial bores 15a, 15b, 16a, 16b extending through the terminal filter element 5 into the hollow axial bore of the terminal filter element 5. Of course, the upstream filter element could be replaced with a hollow bore filter element as shown in Figure 5.

Figure 7 shows a sixth embodiment of a consumable 1 which is the same as the fourth embodiment except that the wrapping layer 3 does not completely circumscribe the cardboard tube spacer 6 such that there is an annular gap 9 between the tipping layer 7 and the cardboard tube spacer 6 downstream of the end of the wrapping layer 3. Furthermore, the first row of ventilation holes 13a, 13b extend through the wrapping layer 3 and through the upstream filter element 4 into the hollow bore of the terminal filter element 4 whilst the second row of ventilation holes 14a, 14b extending only through the wrapping layer 3.

Figure 8 shows the fourth embodiment inserted into an HNB device 10 comprising a rod-shaped heating element 20. The heating element 20 projects into a cavity 11 within the main body 12 of the device.

The consumable 1 is inserted into the cavity 11 of the main body 12 of the device 10 such that the heating rod 20 penetrates the aerosol-forming substrate 2. Heating of the reconstituted tobacco in the aerosol forming substrate 2 is effected by powering the heating element (e.g. with a rechargeable battery (not shown)). As the tobacco is heated, moisture and volatile compound (e.g. nicotine) within the tobacco and the humectant are released as a vapour and entrained within an airflow generated by inhalation by the user at the terminal filter element 5.

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 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. An aerosol-forming article comprising an aerosol-forming substrate and a filter element wherein the article comprises at least one radial air flow path into the filter element.

2. An article according to claim 1 wherein the article is a heat-not-burn (HNB) consumable.

3. An article according to claim 1 or 2 wherein the filter element is a solid filter element.

4. An article according to claim 3 comprising a plurality of radial air flow paths circumferentially- arranged around the filter element.

5. An article according to claim 4 comprising a plurality of axially spaced, circumferentially-extending rows of radial flow paths.

6. An article according to any one of the preceding claims wherein the radial air flow path(s) is/are provided in a terminal filter element at the downstream axial end of the article/consumable and/or in an upstream filter element provided upstream from the downstream axial end of the article/consumable and downstream of the aerosol-forming substrate.

7. An article according to claim 6 wherein the radial air flow path(s) is/are provided in the terminal filter element and the article further comprises an upstream filter element.

8. An article according to claim 7 wherein the terminal filter element is at least partially circumscribed by a tipping layer and the radial air flow path(s) is/are provided by one or more ventilation holes provided in the tipping layer surrounding the terminal filter element.

9. An article according to claim 7 or 8 wherein the radial air flow path(s) is/are provided by one or more radial bores extending into the terminal filter element.

10. An article according to claim 6 wherein the radial air flow path(s) is/are provided in the upstream filter element and the article further comprises a terminal filter element.

11. An article according to claim 10 wherein the upstream filter element is at least partially circumscribed by a wrapping layer and the radial air flow path(s) is/are provided by one or more ventilation holes provided in the wrapping layer surrounding the upstream filter element.

12. An article according to claim 10 or 1 1 wherein the radial air flow path(s) is/are provided by one or more radial bores extending into the upstream filter element.

13. An article according to any one of claims 7 to 12 further comprising a spacer element or an aerosolcooling element interposed between the upstream filter element and the terminal filter element.

14. An aerosol-forming article comprising an aerosol-forming substrate and a hollow bore filter element wherein the article comprises at least one radial air flow path into the hollow bore filter element.

15. An article according to claim 14 wherein the article is a heat-not-burn (HNB) consumable.

16. An article according to claim 15 comprising a plurality of radial air flow paths circumferentially- arranged around the hollow bore filter element.

17. An article according to claim 16 comprising a plurality of axially spaced, circumferentially-extending rows of radial flow paths.

18. An article according to any one of claims 14 to 17 wherein the radial air flow path(s) is/are provided in a terminal hollow bore filter element at the downstream axial end of the article/consumable and/or in an upstream hollow bore filter element provided upstream from the downstream axial end of the article/consumable and downstream of the aerosol-forming substrate.

19. An article according to claim 18 wherein the radial air flow path(s) is/are provided in the terminal hollow bore filter element and the article further comprises an upstream hollow bore filter element.

20. An article according to claim 19 wherein the terminal filter element is at least partially circumscribed by a tipping layer and the radial air flow path(s) is/are provided by one or more ventilation holes provided in the tipping layer surrounding the terminal hollow bore filter element.

21. An article according to claim 19 or 20 wherein the radial air flow path(s) is/are provided by one or more radial bores extending into the terminal hollow bore filter element.

22. An article according to claim 18 wherein the radial air flow path(s) is/are provided in the upstream hollow bore filter element and the article further comprises a terminal hollow bore filter element.

23. An article according to claim 22 wherein the upstream filter element is at least partially circumscribed by a wrapping layer and the radial air flow path(s) is/are provided by one or more ventilation holes provided in the wrapping layer surrounding the upstream hollow bore filter element.

24. An article according to claim 22 or 23 wherein the radial air flow path(s) is/are provided by one or more radial bores extending into the upstream hollow bore filter element.

25. An article according to any one of claims 19 to 24 further comprising a spacer element or an aerosol-cooling element interposed between the upstream filter element and the terminal filter element.

26. A system comprising a smoking substitute article according to any one of the preceding claims and a device comprising a heating element.

27. A system according to claim 26 wherein the device comprises a main body for housing the heating element and the heating element comprises an elongated heating element.

28. A method of using the system according to claim 26 or 27, the method comprising:

inserting the article into the device; and

heating the article using the heating element.

29. A method according to claim 28 comprising inserting the article into a cavity within a main body of the device and penetrating the article with the heating element upon insertion of the article.

30. A filter element for an aerosol-forming article, the filter element comprising at least one radial bore.

31. A filter element for an aerosol-forming article, the filter element comprising an axial bore and at least one radial bore.