CN110891434A

CN110891434A - Tobacco-containing consumable for an aerosol-generating device

Info

Publication number: CN110891434A
Application number: CN201880034364.8A
Authority: CN
Inventors: 大卫·麦克劳林; 杰森·霍普斯
Original assignee: Aluchi Holdings Ltd
Current assignee: Aluchi Holdings Ltd
Priority date: 2017-05-24
Filing date: 2018-05-24
Publication date: 2020-03-17
Anticipated expiration: 2038-05-24
Also published as: RU2019137577A; GB2562764A; WO2018215781A1; GB201708331D0; JP2023055920A; US20200113227A1; CA3064084A1; EP3629779A1; RU2769811C2; KR20200031079A; JP2020520678A; RU2019137577A3; CN110891434B; JP7224343B2; RU2022108774A

Abstract

A non-combustible smoking article for use in combination with a heat source to produce an inhalable aerosol; the non-combustible smoking article comprises at least one tobacco-derived portion, at least one distal filter portion, and at least one mouth-end filter portion held together in an outer wrapper; the complete article has a compressibility < 10% on the longitudinal axis.

Description

Tobacco-containing consumable for an aerosol-generating device

Many alternatives to traditional combustible tobacco products have been marketed in recent years.

The electronic cigarette uses battery power to heat a nicotine-containing aerosol generating liquid to form an inhalable nicotine-containing aerosol. Such products tend to be free of tobacco.

The heated tobacco product uses a number of different energy sources and means to heat a tobacco-containing consumable to produce an inhalable aerosol containing some tobacco-derived ingredients, including flavorants and nicotine.

There are also a number of different "hybrid" products that can combine the technologies from e-cigarettes and from heated tobacco products to produce an inhalable nicotine-containing aerosol, where the flavourants and nicotine can be derived from the aerosol-generating liquid or tobacco portion.

Specific examples of the prior art include:

WO 9639880 and WO 2013190036 describe a cigarette-like cylindrical consumable article having a distal end comprising a tobacco-derived material (typically a crimped reconstituted tobacco sheet), a mouth end filter, typically comprising a plurality of segments, and an outer wrapper made of paper. The article is intended to be electrically heated in order to produce an inhalable nicotine-containing aerosol.

WO 2016207407 also describes a tobacco consumable intended to be consumed by heating, namely a distal tobacco-derived portion, a mouth end filter, and a paper overwrap.

US 2009151717 describes a small metallic capsule ("pod") having a foil lid which is pierced prior to use. Within the pod, the tobacco-derived material typically includes finely ground tobacco particles, humectant, and flavoring agents.

WO2016159013 describes a device in which an aerosol is generated by heating a liquid, the aerosol then passing through a separate tobacco portion; the tobacco portion imparts flavor and/or nicotine to the final aerosol. The tobacco portion may be held within a moulded plastics capsule having a mesh at the distal end and a small filter at the mouth end.

WO 2016135342 describes a product which operates in a similar manner to that described in WO2016159013, however, comprising as a unit a tobacco portion and a liquid heating unit. The tobacco portion is held within a molded plastic structure having a filter at the mouth end.

There are some recognized limitations with respect to consumable units for these products.

For example, with consumables manufactured using cigarette making techniques, a user may mistakenly ignite the consumable and may inhale unintended and/or undesired combustion products. Moreover, consumables that utilize plastic or metal bladders require custom manufacturing machinery, have limited environmental recyclability, and are costly in materials and manufacturing.

The present invention describes a tobacco-containing consumable article for use in an aerosol-generating device, the consumable article comprising at least a tobacco-derived portion, a distal filter portion, and a mouth end filter portion held together in a continuous overwrap, and having a compressibility of less than 10%.

The article may have a total pressure drop along its longitudinal axis of <120mm water. The pressure drop is preferably in the range of 5 to 40mm water, more preferably in the range of 10 to 30mm water.

Such consumables may be manufactured using conventional cavity filter making techniques well known in the tobacco industry and shown for example in US 6537186. In this prior art arrangement, the filter is manufactured with a distal filter portion, a cavity for typically receiving solid particulate material (such as activated carbon), and a mouth end filter portion all held together by a paper overwrap. There are also products which utilise the tobacco-derived material within the cavity to flavour or reduce the flavour of smoke as it passes through the filter.

The present invention thus allows consumables to be produced using well-established manufacturing techniques through readily available high-speed production machinery, at low material and production costs, with material and design flexibility, and is compatible with a variety of aerosol-generating systems.

In some examples, the article can alter one or more other sensory characteristics of the aerosol (e.g., alter the feel or odor or appearance of the aerosol to the user).

In some examples, the article may include a substance that changes the PH of the aerosol (e.g., changes the acidity or alkalinity of the aerosol) by lowering or raising the PH.

In some examples, the article can alter (e.g., reduce) the amount of aldehyde in the aerosol.

As used herein, a non-combustible smoking article refers to an article comprising a tobacco-derived portion that is not intended to be wholly or partially combusted during use, and no portion of the article is intended to be ignited during use. In addition, the article is constructed to resist ignition by the use of a filter material (such as cellulose acetate) at the distal and mouth ends.

The term "aerosol" should be interpreted to include gases, vapors, liquid droplets, condensates, particulates, and combinations thereof. Inhalable aerosols are those having an average particle size of 0.1 to 10 μm, more preferably 0.1 to 1.5 μm, as measured by laser dispersion.

Examples of the invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a schematic side view of an article according to the present invention;

FIG. 2 is a schematic side view of an article according to the present disclosure, showing the longitudinal axis;

FIG. 3 is a side perspective view of an exemplary filter portion and overwrap for use in the present invention employing multiple layers in its outer wrap;

fig. 4, 5, and 6 are side schematic views of exemplary articles having different overwrap configurations according to the present invention;

FIGS. 7 and 8 are schematic views of apparatus employed in combination with the articles of the present invention;

FIG. 9 illustrates an exemplary filter portion that may be employed in articles of the present disclosure; and

fig. 10 is a schematic of an alternative method of producing vapor using the article of the present invention.

Fig. 1 depicts the basic construction of an article of the present invention. The mouth end 3 is the end of the article intended to be the outlet of the aerosol towards the user. The distal end 1 is the opposite end of the article, typically intended to serve as an inlet for air and other materials into the article. With a tobacco portion therebetween. By way of example, the length of the tobacco portion 2 is in the range 7mm to 17mm, preferably in the range 10mm to 13mm, the length of each of the

filter portions

1, 3 is in the range 3mm to 15mm, preferably in the range 4mm to 6mm, and the diameter of the flavour containers is in the range 5mm to 8.5 mm. The dimensions depend on the following desired combination: sufficient material is provided within the tobacco portion 2 to provide the desired flavour effect while ensuring a balance between the total three segments to provide a suitable pressure drop while maintaining overall product strength and compressibility.

In the example of fig. 1, portion 2 is a tobacco-derived portion that may include a single tobacco grade, a mixed tobacco grade, a leaf, a stem, dust, reconstituted tobacco, washed tobacco, extracted tobacco, treated tobacco, tobacco extract, and mixtures thereof. The tobacco-derived part 2 can be produced from a tobacco plant by methods including harvesting, drying, cutting, shredding, grinding, extracting, reconstituting, extruding, and combinations thereof. The tobacco-derived portion 2 can be present in the form of leaves, stems, dust, reconstituted flakes, curls, folds, shapes, beads, granules, and mixtures thereof. In most examples, the tobacco part 2 comprises tobacco, but other botanical or aroma agents may also be used. In a variation of the illustrated example, the tobacco portion 2 may be occupied by a cut tobacco rod, or by ground tobacco, in whole or in part. The choice of material for the tobacco portion 2 depends on many factors, such as the level of flavour delivery desired and the requirement to meet a suitable pressure drop.

In a preferred embodiment of the invention, the tobacco-derived part 2 is obtained by: carefully selecting flue-cured tobacco grades based on desired taste attributes and low levels of undesirable chemicals; reducing the particle size of the plant material by cutting or grinding to a size suitable for further processing; treating the tobacco material to further reduce undesirable constituents via a suitable combination of processes including liquid extraction, heat treatment, pressure treatment, and chemical treatment; adding raw materials including a humectant to produce an aerosol and a fragrance; reconstituting the tobacco into a sheet-like pattern; drying to produce a stable material which is added to the smoking article as a crimped sheet, intact or as pieces of cut or shredded sheet. Although size reduction is preferably performed at an early stage in the process, and extraction is preferably performed prior to the addition of the scents to minimize loss of the added scents, the above steps may be interchanged. Although the flavoring/humectant may be added at the end, drying is normally the final stage.

In some examples, cut tobacco filler is used in the tobacco portion 2, in which case the density of the cut tobacco filler may be in the range of 150-. Control of this size ensures that the maximum possible amount of tobacco is provided within the volume of the tobacco portion 2, so that maximum transfer into the aerosol is achieved.

In some examples, the tobacco portion 2 includes a flavoring material that has been ground or otherwise treated or formed such that the flavoring material is in the form of particles, such as powders, particulates, grains, fibers, beads, pellets, and the like, for example, to increase the active surface area or amount of the flavoring material in order to maximize the amount of flavoring imparted to the vapor and/or aerosol flow through the article.

As used herein, the terms "flavour" and "aroma" may refer to materials that may be used to produce a desired taste or aroma in a product for adult consumers as permitted by local regulations. They may include extracts (e.g., licorice, hydrangea, japanese bark lily leaves, chamomile, fenugreek, clove, menthol, japanese mint, anise, cinnamon, vanilla, wintergreen, cherry, berry, peach, apple, jungle mark (Drambuie), bourbon, scotch whisky, whiskey, spearmint, peppermint, lavender, cardamom, celery, balsamiferous wood, nutmeg, sandalwood, bergamot, geranium, honey essence, rose oil, vanilla, lemon oil, orange oil, cinnamon, caraway, cognac brandy, jasmine, ylang, sage, fennel, allspice, ginger, anise, coriander, coffee or mint oil of any species in the genus mentha), flavour enhancers, bitter receptor site blockers, sensory receptor site activators or stimulators, sugars and/or sugar substitutes (e.g., sucralose, Acesulfame potassium, aspartame, saccharin, cyclamate, lactose, sucrose, glucose, fructose, sorbitol, or mannitol) and other additives, such as charcoal, chlorophyll, minerals, botanicals, or breath fresheners. They may be imitation, synthetic, or natural raw materials or mixtures thereof. They may be in any suitable form, such as oil, liquid, solid, or powder. For example, a liquid, oil, or other such fluid flavorant may be impregnated into a porous solid material to impart a flavor and/or other characteristic to that porous solid material. As such, a liquid or oil is a component of the material in which it is immersed.

To prevent excessive pressure drop, it is preferred to have the long axis of the tobacco-derived sheet extend parallel to the longitudinal axis 6 of the article of the invention to form channels for the passage of air (see figure 2, section 2). In an alternative preferred embodiment of the invention, the tobacco-derived material is prepared as above, except that the tobacco-derived material is reconstituted into a granular or particulate form that can then be added to the invention. Preferably, the particulate or particulate tobacco-derived material is produced by extrusion, as this ensures particle size and shape and uniform distribution of any added flavourant or humectant.

Where the material of the tobacco portion 2 comprises continuous fibre ground tobacco, the tobacco weight is preferably in the range of 2mg to 6mg per millimetre of tobacco portion.

Where the material of the tobacco portion 2 comprises cut tobacco ground tobacco, the tobacco weight is preferably in the range 26 mg to 15mg per mm of tobacco portion.

Fig. 2 shows the longitudinal axis 6 of the article of the invention, taken as the long axis of the article and extending from the spout end 3 to the distal end 1. The other axis is taken perpendicular to this longitudinal axis. The definition of such an axis is very important when measuring the key physical parameters that control the integrity of the product during storage and use, as well as the sensory experience received by the user.

The "pressure drop" or "draw resistance" uses the Coresta recommendation method 41.

(https:// www.coresta.org/sites/default/files/technical _ documents/main/CRM _41-update 2-0. pdf) and expressed in millimeters of water column equivalents. This design feature determines how a volume of aerosol can be extracted from a consumable/device with reasonable effort by a user.

"compressibility" is measured on the longitudinal axis 6 by applying a fixed force of 10 newtons at point 5 (see fig. 2) and measuring deflection distance as a percentage of total product length. Such measurements may be performed using an electromechanical fixture 3300 from Instron, inc.

In fig. 1, part 4 shows an "overwrap": the sheet or sheets of material providing the outer surface of the article serve to hold the individual elements (distal filter 1, tobacco-derived portion 2, and mouth end filter 3) in sequence relative to one another and provide the article with structural strength sufficient to meet the user's desired handling, particularly during insertion and removal from the associated device. The overwrap 4 typically comprises paper, plastic, foil, laminate, or a combination thereof. The overwrap 4 may comprise a single layer over the entire article, or may have multiple layers at different points (as shown in portions 8 and 9 in fig. 3), as may be required depending on the underlying construction of the article, e.g., multi-segment filter portions are typically held together with an outer wrap to aid in the manufacturing process. The grammage of the overwrap particularly relevant to the present invention is preferably in the range 20-100g/m²(gsm) range. Preferred embodiments use a concentration in the range of 40-200g/m²A rigid non-porous overwrap of the range of (1), the rigid non-porous overwrap consisting of a transparent cellulose-based paper without chalk overprinted with a metallic ink. The lower limit of grammage is generally determined by the requirements of opacity and physical strength of the final consumable. The upper limit of the grammage range is set by the operability of the machine, which can be implemented if the overwrap material is too thick. For the preferred embodiment, a rigid non-porous overwrap without chalk is used, which has the advantage that printing can be done on specific areas to provide shaped windows, logos, etc.

In some examples, the overwrap 4 is configured such that it acts as a liquid barrier preventing liquids (e.g., condensate formed around the article when in use) from entering the interior of the article and wetting the tobacco portion 2. In one example, a liquid barrier wrap layer is used in the outer wrap 4, which barrier wrap layer comprises a barrier material or a Natureflex film or other suitable polymer film impregnated therewith.

In a preferred embodiment of the invention, the overwrap 4 is supplied as a continuous roll of material that is rolled in the cross direction, shaped as a continuous cylinder, and attached to itself using glue. While forming this continuous overwrap cylinder, the inner elements (i.e.

filter portions

1, 3 and tobacco-derived portion 2) are provided and attached to the overwrap 4 as appropriate. This continuous cylinder is then cut into discrete tobacco products. This process can be performed in a continuous manner using machines known in the art for producing cavity filters. In an alternative preferred embodiment, the continuous roll of overwrap is formed into a spiral and attached to itself to form a continuous cylindrical shape with a resulting spiral seam (as seen in fig. 4). The spiral arrangement has the further advantage that the seam can provide further structural rigidity to the complete article by preventing compression in the transverse direction.

Fig. 4, 5, and 6 illustrate exemplary embodiments in which region 11 is transparent and region 12 is opaque. A transparent overwrap is defined by the ability to allow a user to visually perceive the contents within the article. Suitable properties can be found in transparent, semi-opaque, and translucent materials. Accordingly, a transparent region may be created within the overwrap 4 by changing the composition of the overwrap 4 in that region in a manner that includes reducing the amount of printing, reducing the amount of opaque layer, removing the foil layer, or a combination thereof. The preferred embodiment utilizes clear cellulose-based paper opacified with metallic ink to create a generally foil-like appearance and has an area without metallic ink to serve as a transparent window 11 to view the contents within the article. Most preferably, these transparent windows 11 are aligned with the tobacco-derived portion 2.

During storage and use, the physical characteristics of the overwrap 4 can be affected by the absorption of volatiles, liquids, and aerosol components. For example, paper-based overwraps can absorb moisture and other liquids, which softens the overwrap, reducing its structural integrity; this may be undesirable as it may affect the ability of the user to remove the article from the associated device. This may also have a negative impact on the visual aesthetics of the overwrap, such as causing staining. Accordingly, it is desirable to provide an overwrap that resists absorption and thus maintains desirable structural properties and appearance. To resist absorption, the overwrap may be composed of plastic and foil; having an internal layer of plastic or foil; having an inner surface coated with a varnish or lacquer; consisting of paper having a low tendency to absorb liquid, and combinations thereof. These may include a three-layer foil having a PE: Al: PET type construction. In a preferred embodiment, the overwrap is a chalk-free, transparent cellulose-based paper that exhibits a low tendency to absorb. In an alternative preferred embodiment, the overwrap 4 is a transparent film of plastic. In an alternative preferred embodiment, the outer wrapper 4 is a paper based material coated on the inner surface with a layer of Alkyl Ketene Dimer (AKD).

The filter portion (fig. 1, portions 1 and 3) serves as a physical barrier to contain the tobacco-derived portion 2 and to maintain the overall structural integrity of the smoking article, primarily on the short axis, while allowing the required air and aerosol to pass through. In some examples, the material of the filter is moisture resistant, such that the

filter portions

1, 3 retain their shape in use. The mouth end filter portion 3 may furthermore serve to prevent undesired fine dust particles from the tobacco-derived portion 2 from reaching the user and to remove aerosol particles larger than those of the inhalable aerosol.

The

filter portions

1, 3 may each be provided by a filter portion 21. To enhance the airflow through the present invention, the pressure drop across the filter portion 21 (shown in FIG. 9) may be reduced by introducing one or more airflow channels 22 in the longitudinal axis. The airflow passage 22 may run the entire length of the filter section. Preferably the airflow channel 22 passes through up to 95% of the length of the filter portion, leaving at least 5% of the filter portion intact to retain tobacco particles. Once the filter portion 21 is formed, the gas flow channels 22 may be introduced by burning through the filter material using a laser or by punching the channels 22 using mechanical pins. Preferably, the gas flow channels 22 are formed by introducing a mandrel or pin into the filter material during the formation process that shapes the channels.

In some examples, the pressure differential across either of the

portions

1, 3 is in the range of 0.1mm to 2mm water column per mm segment length.

The filter portion 21 is typically constructed of cellulose acetate, paper, plastic, polymers such as polyethylene, polypropylene, or polylactic acid, and combinations thereof. In a preferred embodiment of the invention, the filter section 21 is constructed of cellulose acetate fibers plasticized with up to 15% triacetin. The filter portion 21 may be homogenous or be made up of a plurality of consecutive segments. The filter portion 21, more preferably the mouth end filter portion 3, may contain diluents, flavorants, and aesthetic elements.

Different additional flavour components (e.g. flavour capsules in the distal portion 1 and flavour threads or threads in the mouth portion 1) may be placed in each

end filter portion

1, 3.

In some examples, the

filter portions

1, 3 comprise fibrous material, and may be, for example, fibrous material typically used as filter material in conventional cigarettes, examples including cellulose acetate fibers, polypropylene fibers, polyester fibers, and paper (including crimped paper). Other materials such as nylon and the like may be used.

In another example, the material of the tobacco portion 2 and the material in the two

filter portions

1, 3 comprise a plurality of chopped CA fibers (e.g., fibers cut using a so-called Turmalin apparatus) that are randomly oriented. Chopped CA fibers with ground tobacco, for example, in tobacco portion 2, may use just enough fibers to hold the ground tobacco in rod-like form. The benefits of this arrangement allow for a lower pressure drop of the vapour and/or aerosol stream and, in addition, reduced or no need for plasticisers (e.g. triacetin) to maintain the rod-like form required by the continuous fibre CA. Furthermore, the use of chopped CA fibers enables the use of less CA and more tobacco than if long continuous CA fibers were used.

In some examples, the percentage of the weight of the first flavour component (and any other components, e.g. charcoal, plasticiser) in the

filter portions

1, 3 to the weight of the material of the tobacco portion 2 is in the range 10% to 90%, preferably in the range 70% to 90%.

In the particular case where the article comprises continuous fibres and the tobacco portion 2 comprises ground tobacco, the tobacco weight to fibre weight is preferably in the range 40% to 60%, most preferably in the range 45% to 55%. The fiber weight is preferably in the range of 75% to 95%, most preferably in the range of 80% to 90%.

The diluent removes undesirable chemicals from the aerosol and includes solid particles of carbon, activated carbon, pyrolytically-derived carbonaceous resins, silica, chemically activated derivatives of carbon and silica, metal-based catalysts, and mixtures thereof.

Flavorants add desirable organoleptic properties to the aerosol and may be present in the tobacco-derived portion, the filter portion, and combinations thereof. Common flavors include menthol, peppermint, vanilla, licorice, fruit extracts, esters, acetals, fructans, and combinations thereof. The flavorant may be present in the filter matrix, the tobacco-derived material, in a flavor thread, in a bead, in a breakable capsule, in a non-breakable capsule, encapsulated in a protective matrix, encapsulated in a molecule comprising cyclodextrin, and combinations thereof.

The aesthetic element includes a colorant dispersed within the filter matrix or located in specific areas, and the filter is shaped to form a unique pattern, logo, or is recessed or fluted, or a combination thereof. This is illustrated in fig. 3, which shows an exemplary filter component provided with a mouth end having a recessed portion 10. In combination with the component 7, a mouth end filter portion 3 having a recess 10 therein may be provided for use in an article. This construction provides an aesthetically pleasing construction that can contribute to product strength through the use of a layered overwrap 4. It also allows the possibility of providing shorter filter members 7 which may reduce the overall pressure drop. By way of such example, the filter portion 7 will typically be 6mm long or longer to ensure that the filter portion retains material in the tobacco portion 2, yet provides suitable structural integrity while controlling the pressure drop and compressibility of the overall article.

Figures 7 and 8 depict the present invention and a device for generating an aerosol for an electronic cigarette. The device uses the battery power supply 14 to heat the resistance wire 17 in order to volatilize e-liquid from the reservoir 16, which liquid is typically free of nicotine. The article 19 of the invention is inserted into the electronic vaping device at point 18. The first aerosol generated by the resistive wire 17 passes through the article 19 and is modified to generate an inhalable aerosol 20. The modification of the first aerosol comprises the addition of nicotine and other flavorants of the invention. Modification may also include removal of undesired chemical constituents via the diluent, and removal of undesired aerosols and other particles from the aerosol.

In an alternative embodiment, the first aerosol further comprises a chemical for assisting in the incorporation of the desired chemical from the tobacco-derived portion 2 into the aerosol. Preferably, the first aerosol comprises volatile acids for binding free base nicotine from the tobacco-derived portion 2 and thereby enhancing the amount of nicotine in the inhaled aerosol. Suitable volatile acids include ascorbic acid, pyruvic acid, and levulinic acid.

Fig. 10 shows an alternative use of the invention, wherein the invention is inserted into a device having a power source 14 which uses a heat source 23 to directly heat the tobacco portion 2. The action of heat from the associated device causes volatile components to be released from the present invention, which form an inhalable aerosol. The heat source 23 comprises one of an electrically driven or chemically reactive heating device. Electrically driven options include metal heating elements, resistive wires, thin film heaters, ceramic heaters, and combinations thereof in combination with batteries or battery cells. Alternatively, the electrically driven heat source 23 may rely on induction, wherein an alternating electromagnetic field is generated, which in turn generates heat in a suitably placed susceptor element 24. The efficiency of the induction is improved when the susceptor element 24 is in close proximity to the material to be heated, and therefore the susceptor element 24 is preferably placed within the tobacco-derived material or as part of the outer wrapper in contact with the tobacco-derived portion. In the case of induction heating, the power supply and circuitry may be configured to operate at high frequencies. Preferably, the power supply and circuitry may be configured to operate at a frequency of between about 80kHz and 500kHz, preferably between about 150kHz and 250kHz, more preferably about 200kHz, and the components may be arranged to operate, in use, with a fluctuating electromagnetic field having a magnetic flux density of between about 0.5 tesla (T) and about 2.0T at the point of highest concentration. The induction coil may typically comprise Litz (Litz) wire or Litz cable, although the induction coil may comprise any suitable material. The susceptor may include, but is not limited to, one or more of aluminum, iron, nickel, stainless steel, and alloys thereof (e.g., nichrome). By applying an electromagnetic field in its vicinity, the susceptor may generate heat due to eddy currents and hysteresis losses, thereby causing conversion of electromagnetic energy to thermal energy.

Chemical reaction driven heat sources include combustion, oxidation, redox, and other exothermic reactions.

Humectants are additives used to retain water within the matrix and include polyols such as propylene glycol, glycerin, PEGs of various molecular weights, sugar alcohols (such as sorbitol), and combinations thereof. In the present invention, the volatilized humectant also functions to produce aerosol droplets. Preferably, the humectant is a mixture of propylene glycol and glycerin.

The pH modifying agents include acids, bases, and buffers, and can be used to change the ionization state of chemicals in the tobacco-derived portion, thereby changing its volatility. Notably, the free base nicotine predominating at alkaline pH is more volatile than the nicotine salt predominating at acidic pH. In a preferred embodiment, sufficient alkaline agent is added to the tobacco-derived portion to achieve an overall pH >7, thereby making more nicotine available for volatilization into an inhalable aerosol. More preferably, the overall pH is > 8. Suitable alkaline agents include metal carbonates, metal bicarbonates, metal hydroxides, and ammonium salts.

In one embodiment of the invention, the tobacco-derived portion 2 is produced by providing a blend of tobacco grades including flue-cured tobacco and air-cured tobacco, the tobacco having a consistency of

Standard chemical composition, i.e. tobacco specific nitrosamine (NNN + NNK) content<1mg/kg, benzo a pyrene content<1.25 ug/kg. After mixing, the tobacco was reduced in size by first shredding and then grinding to pass through a No.18 screen to make the particles size ═<1 mm. Adding 50% of deionized water with equivalent mass to the ground tobacco; 2% by mass equivalent of a flavour-a 50:50 mixture of menthol and peppermint oil; 0.375% equivalent mass of pH modifier-sodium hydroxide. The resulting tobacco paste was passed through a Coperion extruder having a barrel temperature of 250 ℃ and a pressure of 4atm, which was connected to a pelletizer, to produce a shaped material having a particle size of about 1.5mm in diameter. The tobacco-derived particles are then dried under vacuum to<10% moisture. The dried tobacco particles are then sieved to produce fractions in the range of 0.2mm to 1.25 mm. The mouth-end and

distal filter portions

1, 3 are manufactured using a Hauni filter rod making machine.

Filter sections

1, 3 were made from cellulose acetate tow 6Y17 using 10.1mg tow per mm filter length;plasticization with 12% w/w triacetin; a26 gsm 2000CU plug wrap was attached with PVA glue. The dimensions of the final filter portion were 8mm in diameter and 6mm in length. Assembly of non-combustible tobacco articles was performed on a Molins cavity filter machine using a SWM paper overwrap PPW 35 coated on its inner surface with 0.1% AKD. The construction of the article was a 6mm filter portion, a 17mm cavity with 250mg of tobacco derived material, a 6mm filter portion attached with PVA glue. The resulting final product has a total pressure drop of 40 to 65mm water and a compressibility on the vertical axis of-3%.

By means of the invention, by controlling the compressibility of the article, it is possible to provide a device that is easy for a user to handle and remove from a vapor-generating device without deforming or damaging, even if the generation of vapor during use could potentially compromise the mechanical properties of the article. By optionally controlling the suction pressure, a pressure drop may be ensured, so that the user can comfortably generate the suction pressure when receiving the vapour. Furthermore, the invention ensures that an article may be provided in which a suitable vapour-generating material is retained, which article is aesthetically pleasing and is easy and simple to manufacture.

Claims

1. A non-combustible smoking article for use in combination with a heat source to produce an inhalable aerosol; the non-combustible smoking article comprises at least one tobacco-derived portion, at least one distal filter portion, and at least one mouth-end filter portion held together in an outer wrapper; the complete article has a compressibility < 10% on the longitudinal axis.

2. A smoking article according to claim 1, arranged to have a total pressure drop of <120mm water column over it in the longitudinal direction.

3. A smoking article according to claim 1 or 2, arranged such that, in use, the smoking article modifies a first aerosol generated by the heat source to generate the inhalable aerosol.

4. A smoking article according to claim 1 or 2, arranged such that, in use, the smoking article provides a volatile component to the inhalable aerosol under the action of the heat source.

5. A smoking article according to any preceding claim, further comprising inductive elements dispersed within the tobacco-derived portion such that, in use, electromagnetic energy can be applied to the inductive elements to generate heat.

6. A smoking article according to any preceding claim, wherein the tobacco-derived portion comprises at least one from the group of: a fragrance, a humectant, and a pH modifier.

7. A smoking article according to any preceding claim, wherein the tobacco-derived portion comprises a flavourant, a humectant, and a pH modifier.

8. A smoking article according to any preceding claim, wherein the overwrap comprises at least one transparent region.

9. A smoking article according to any preceding claim, wherein the overwrap is arranged to resist absorption of volatile and aerosol constituents of the tobacco-derived portion such that the total weight increase caused by absorption after use is < 10% of the original overwrap weight.

10. A smoking article according to any preceding claim, wherein the outer wrapper is wound in a helical direction relative to the longitudinal axis of the article.

11. A smoking article as defined in any preceding claim, wherein the mouth end filter portion comprises at least two distinct regions that are adjoined together.

12. A smoking article according to any preceding claim, wherein the mouth end filter portion and the distal filter portion comprise, alone or in combination, at least one from the group of: aesthetic elements, fragrances, and diluents.

13. A smoking article according to any preceding claim, wherein the mouth end filter portion and the distal filter portion comprise flavourant and aesthetic elements, either individually or in combination.

14. A smoking article according to any preceding claim, wherein the mouth end filter portion and the distal filter portion comprise diluent, flavourant, and aesthetic elements, either alone or in combination.

15. A smoking article according to any preceding claim, wherein at least one of the filter portions comprises at least one airflow channel on the longitudinal axis.

16. A method of manufacturing a smoking article according to any preceding claim, the method comprising the steps of: first forming the filter portions, arranging the filter portions within an outer wrap in such a way that a cavity is formed between the filter portions; filling the cavity with the tobacco-derived material and enclosing the overwrap material to form an integral unit.