Aerosol generating material

Abstract

An aerosol generating material comprising a botanical material is provided, wherein the aerosol generating material is in the form of a sheet or a shredded sheet having one or more homogeneous properties selected from the group consisting of: thickness, permeability, density, surface roughness or visual appearance. An article for use in a non-combustible aerosol-provision system comprising the aerosol generating section comprising the aerosol generating material is also provided, as well as a method to make the aerosol generating material.

Description

[0001] Aerosol generating material

[0002] Technical Field The present disclosure relates to an aerosol-generating material, a method for manufacturing an aerosol-generating material and consumables comprising an aerosolgenerating material.

[0003] Background

[0004] Aerosol provision products produce an aerosol during use, which is inhaled by a user. For example, tobacco heating devices heat an aerosol generating material such as tobacco to form an aerosol by heating, but not burning, the substrate. Aerosol provision products commonly include an aerosol-generating section or region, which generate an aerosol in use, and a mouthpiece through which the aerosol passes to reach the user’s mouth.

[0005] Such products suffer from the problem that the aerosol generating material is non- homogenous, for example in its density and thickness. In addition, commonly used methods to prepare sheets of such aerosol generating materials generate sheets or shredded sheets with rough surfaces, which may negatively affect air flow though the product. The surfaces of said sheets may also differ in roughness on each side, further resulting in inconsistent air flow. These features provide an inconsistent flavour delivery to the user and there is therefore a need to improve these properties in the aerosol generating material. Aerosol generating materials can be made by extruding a mixture of its components.

[0006] This provides the benefit of reduced water content, which in turn enjoys the advantages of requiring less drying (for example in terms of drying time or temperatures) in order to prepare an aerosol generation material. However, this suffers from the problem poor control of the homogeneity of the aerosol generating material.

[0007] Summary

[0008] According to a first aspect of the invention, there is provided an aerosol generating material, wherein the aerosol generating material is in the form of a sheet or a shredded sheet having one or more homogeneous properties selected from the group consisting of: thickness, permeability, density, surface roughness or visual appearance.

[0009] According to a second aspect of the invention, there is provided an aerosol generating material comprising a botanical material, wherein the aerosol generating material is in the form of a sheet or a shredded sheet having one or more homogeneous properties selected from the group consisting of: thickness, permeability, density, surface roughness or visual appearance. In some embodiments, the aerosol generating material has an area density of from about 150 to about 210 g / m2.

[0010] In some embodiments, the aerosol generating material has a volume density of from about 0.2 to about 1 g / cm3.

[0011] In some embodiments, the aerosol generating material comprises a first surface and a second surface, and wherein the first and second surfaces have substantially the same surface roughness. In some embodiments, the first and second surfaces have an average roughness (Ra) according to ISO Standard 4287 of from about 15 pm to about 20 pm.

[0012] In some embodiments, the aerosol generating material has a thickness of from about 0.15 mm to about 0.35 mm.

[0013] In some embodiments, the thickness does not vary by more than 10% over an area of the sheet.

[0014] In some embodiments, the air permeability of the aerosol generating material is between 5 and 40 s / too cm3.

[0015] In some embodiments, the aerosol generating material has a tensile strength of at least 3 N / i5mm. In some embodiments, the botanical material is in the form of particles. In some embodiments, the particles have a D90 of about 320 to about 350 pm.

[0016] In some embodiments, the aerosol generating material does not comprise tobacco material.

[0017] In some embodiments, the botanical material comprises rooibos.

[0018] In some embodiments, the aerosol generating material comprises water. In some embodiments, the aerosol generating material comprises a water content of about 6.5 to about 9.5 % by weight.

[0019] In some embodiments, the aerosol generating material comprises a botanical material content of about 50 to about 80 % by weight.

[0020] In some embodiments, the aerosol generating material comprises at least one binder.

[0021] In some embodiments, the aerosol generating material comprises a binder content of about 10 to about 25 % by weight.

[0022] According to a third aspect of the invention, there is provided an article for use in a non-combustible aerosol-provision system comprising an aerosol-generating section comprising the aerosol generating material the first or second aspect. In some embodiments, the pressure drop across the article is about 40 to about 120 mmWg.

[0023] In some embodiments, the pressure drop across the aerosol-generating section is about too to about 500 mmWg.

[0024] In some embodiments, the aerosol generating material is in the form of a shredded sheet.

[0025] According to a fourth aspect of the invention, there is provided a method of production of an aerosol generating material according to any preceding claim comprising the steps of: forming a first composition comprising a first binder and an aerosol former; forming a second composition comprising a tobacco material, a filler and optionally a second binder; combining the first composition and the second composition to form a mixture of the first composition and the second composition; extruding the mixture; and rolling the extruded mixture using at least one roller to form the aerosol generating material. In some embodiments, the rolling step uses four rolling presses.

[0026] In some embodiments, the rollers are at most about 0.5 mm apart.

[0027] Brief description of the drawings

[0028] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which sheet 1 refers to an aerosol generating material in the form of a sheet made using a band casting process and sheet 2 and 3 refers to the claimed aerosol generating material in the form of a sheet, and:

[0029] Figure 1 shows a graph showing the thickness of the sheet along the area of the sheet.

[0030] Figure 2 show a graph showing the average surface roughness (Ra) of the first and second surfaces of sheet 1 and sheet 2.

[0031] Figure 3 show a graph showing the average surface roughness (Rz) of the first and second surfaces of sheet and sheet 2.

[0032] Figure 4 show a graph showing the average surface roughness (RSm) of the first and second surfaces of sheet 1 and sheet 2.

[0033] Figure 5 shows air permeability data of sheet 1 and sheet 2.

[0034] Figure 6 is a graph of data collected from a light intensity machine.

[0035] Figure 7 shows a table of data from Figure 6. Figure 8 depicts schematically an exemplary process to make the aerosol generating material.

[0036] Figure 9 is a perspective view of an article for use with a non-combustible aerosol provision device; and

[0037] Figure 10 is a side-on cross-sectional view of the article shown in Figure 9.

[0038] Figure 11 is a simplified schematic view of an exemplary rolling press.

[0039] Detailed description

[0040] The present invention relates to an aerosol generating material with improved homogeneity. As used herein, the term homogeneous refers to substantially uniform composition or character.

[0041] In a first aspect of the invention, an aerosol generating material comprising a botanical material is provided, wherein the aerosol generating material is in the form of a sheet or a shredded sheet having one or more homogeneous properties selected from the group consisting of: thickness, permeability, density, surface roughness or visual appearance.

[0042] In some embodiments, the aerosol generating material may be in the form of a sheet or a shredded sheet. The sheet or shredded sheet has a first and a second surface, the first and second surfaces being the opposite sides of the sheet.

[0043] Aerosol-generating material is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way. Aerosol-generating material may, for example, be in the form of a solid, liquid or semi-solid (such as a gel) which may or may not contain an active substance and / or flavourants.

[0044] The aerosol-generating material may comprise one or more active substances and / or flavours, one or more aerosol-former materials, and optionally one or more other functional material. The aerosol-generating material may comprise a binder, such as a gelling agent, and an aerosol former. Optionally, a substance to be delivered and / or filler may also be present. Optionally, a solvent, such as water, is also present and one or more other components of the aerosol-generating material may or may not be soluble in the solvent. In some embodiments, the aerosol-generating material is substantially free from botanical material. In particular, in some embodiments, the aerosol-generating material is substantially tobacco free.

[0045] The aerosol-generating material may comprise or be in the form of an aerosol- generating film. The aerosol-generating film may comprise a binder, such as a gelling agent, and an aerosol former. Optionally, a substance to be delivered and / or filler may also be present. The aerosol-generating film may be substantially free from botanical material. In particular, in some embodiments, the aerosol-generating material is substantially tobacco free.

[0046] The aerosol-generating film may have a thickness of about 0.015 mm to about 1 mm. For example, the thickness maybe in the range of about 0.05 mm, 0.1 mm or 0.15 mm to about 0.5 mm or 0.3 mm. The aerosol-generating film may be continuous. For example, the film may comprise or be a continuous sheet of material. The sheet maybe in the form of a wrapper, it maybe gathered to form a gathered sheet or it may be shredded to form a shredded sheet. The shredded sheet may comprise one or more strands or strips of aerosol-generating material.

[0047] The aerosol-generating film maybe discontinuous. For example, the aerosol-generating film may comprise one or more discrete portions or regions of aerosol-generating material, such as dots, stripes or lines, which may be supported on a support. In such embodiments, the support may be planar or non-planar.

[0048] The aerosol-generating film may be formed by combining a binder, such as a gelling agent, with a solvent, such as water, an aerosol-former and one or more other components, such as one or more substances to be delivered, to form a slurry and then heating the slurry to volatilise at least some of the solvent to form the aerosol- generating film. The slurry maybe heated to remove at least about 60 wt%, 70 wt%, 80 wt%, 85 wt% or 90 wt% of the solvent.

[0049] The aerosol-generating material may comprise or be an “amorphous solid”. In some embodiments, the aerosol-generating materiel comprises an aerosol-generating film that is an amorphous solid. The amorphous solid maybe a “monolithic solid”. The amorphous solid may be substantially non-fibrous. In some embodiments, the amorphous solid may be a dried gel. The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the amorphous solid may, for example, comprise from about 50wt%, 6owt% or 70wt% of amorphous solid, to about 90wt%, 95wt% or ioowt% of amorphous solid.

[0050] In some embodiments, the aerosol-generating material comprises a botanical material.

[0051] In some embodiments, the botanical material comprises or consist of one or more botanicals or constituents, derivatives or extracts thereof. In some embodiments, the aerosol generating material does not comprise a botanical material.

[0052] As used herein, the term "botanical" includes any material derived from plants or plant material including, but not limited to, extracts, leaves, bark, fibres, stems, roots, seeds, flowers, fruits, pollen, husk, shells or the like. In some embodiments, the botanical material is plant derived material or plant material that has been cut into smaller pieces, for example the plant derived material or plant material may be milled, pulverised, dices, slices, or otherwise partitioned to reduce the size of the pieces. In some embodiments, the botanical material is plant derived material or plant material in the form of particles, as described herein.

[0053] Alternatively, the material may comprise an active compound naturally existing in a botanical, obtained synthetically. The material maybe in the form of liquid, gas, solid, powder, dust, crushed particles, granules, pellets, shreds, strips, sheets, or the like.

[0054] Example botanicals are tobacco, eucalyptus, star anise, hemp, cocoa, cannabis, fennel, lemongrass, peppermint, spearmint, rooibos, chamomile, flax, ginger, ginkgo biloba, hazel, hibiscus, laurel, licorice (liquorice), matcha, mate, orange skin, papaya, rose, sage, tea such as green tea or black tea, thyme, clove, cinnamon, coffee, aniseed (anise), basil, bay leaves, cardamom, coriander, cumin, nutmeg, oregano, paprika, rosemary, saffron, lavender, lemon peel, mint, juniper, elderflower, vanilla, wintergreen, beefsteak plant, curcuma, turmeric, sandalwood, cilantro, bergamot, orange blossom, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, geranium, mulberry, ginseng, theanine, theacrine, maca, ashwagandha, damiana, guarana, chlorophyll, baobab or any combination thereof. The mint may be chosen from the following mint varieties: Mentha Arventis, Mentha c.v., Mentha niliaca, Mentha piperita, Mentha piperita citrata c.v., Mentha piperita c.v., Mentha spicata crispa, Mentha cardifolia, Mentha longifolia, Mentha suaveolens variegata, Mentha pulegium, Mentha spicata c.v. and Mentha suaveolens

[0055] In some embodiments, the botanical material is selected from eucalyptus, star anise, cocoa, hemp and fennel.

[0056] In some embodiments, the botanical material may comprise one or more constituents, derivatives or extracts of cannabis, such as one or more cannabinoids or terpenes. The botanical material may be CBD or a derivative thereof.

[0057] The botanical material maybe a non-tobacco botanical material. A “non-tobacco botanical material” is a botanical material other than tobacco. The use of a non- tobacco botanical material may enhance the sensorial properties of an aerosol produced by the aerosol-generating material produced by the process. The non- tobacco botanical material may produce a particularly neutral aroma profile, for example when rooibos, fennel, star anise, and / or mint are utilised in the aerosolgenerating material. Due to the relatively neutral aroma profile of non-tobacco botanical materials, a relatively neutral aerosol may be formed. Moreover, when one, or more, of these botanicals is used in combination with an active, such as nicotine, the sensory properties attributable to the active may be more readily perceived by the user. For example, the aroma may be enhanced when paired with a flavour such as menthol, spearmint and / or peppermint; berry fruits, citrus fruits, and / or tropical fruits, or any combination of these flavours.

[0058] In some embodiments, the botanical material is rooibos. This provides the advantage that the rooibos provides a suitable texture and density, but does not comprise nicotine. Rooibos advantageously also does not comprise caffeine. Combining one, or more, non-tobacco botanical materials with an active may allow for the sensory properties attributable to the active (such as nicotine or menthol) to be more readily perceived by the user compared with tobacco-based aerosolgenerating materials. As a consequence, any variations in the consistency of the aerosol-generating material may be more detectable by the user when the aerosolgenerating material is heated to produce an aerosol. Therefore, it is desirable to ensure that both the non-tobacco botanical and the active are homogeneously mixed throughout the aerosol-generating material to achieve a product having consistent aerosol properties.

[0059] The aerosol-generating material produced by the process described herein exhibits homogeneous properties and thus the aerosol that is produced by the aerosolgenerating material is relatively consistent.

[0060] In some embodiments, the botanical material is tobacco material. Thus, in some embodiments, the aerosol-generating material comprises tobacco. In some embodiments, the aerosol-generating material does not comprise tobacco. In some embodiments, the aerosol-generating material does not comprise tobacco material is substantially tobacco free.

[0061] As used herein, the term “tobacco material” refers to a material derived from a plant of the Nicotiana species. The selection of the plant of the Nicotiana species is not limited, and the types of tobacco or tobaccos used may vary. The term “tobacco material” may include one or more of tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes. The tobacco material may comprise one or more of ground tobacco, tobacco fibre, cut tobacco, extruded tobacco, leaf tobacco, tobacco stem, reconstituted tobacco and / or tobacco extract. As used herein, “leaf tobacco” means cut lamina tobacco.

[0062] In some embodiments, the tobacco material is selected from flue-cured or Virginia, Burley, sun-cured, Maryland, dark-fired, dark air cured, light air cured, Indian air cured, Red Russian and Rustica tobaccos, and mixtures thereof, as well as various other rare or specialty tobaccos, green or cured. Tobacco material produced via any other type of tobacco treatment which could modify the tobacco taste, such as fermented tobacco or genetic modification or crossbreeding techniques, is also within the scope of the present disclosure. For example, it is envisaged that tobacco plants maybe genetically engineered or crossbred to increase or decrease production of components, characteristics or attributes. In some embodiments, the tobacco material is sun-cured tobacco, selected from Indian Kurnool and Oriental tobaccos, including Izmir, Basma, Samsun, Katerini, Prelip, Komotini, Xanthi and Yambol tobaccos. In some embodiments, the tobacco material is dark air cured tobacco, selected from Passanda, Cubano, Jatin and Besuki tobaccos. In some embodiments, the tobacco material is light air cured tobacco, selected from North

[0063] Wisconsin and Galpao tobaccos.

[0064] In some embodiments, the tobacco material is selected from Brazilian tobaccos, including Mata Fina and Bahia tobaccos. In some embodiments, the tobacco material is selected from criollo, Piloto Cubano, Olor, Green River, Isabela DAC, White Pata, Eluru, Jatim, Madura, Kasturi, Connecticut Seed, Broad Leaf, Connecticut, Pennsylvanian, Italian dry air cured, Paraguayan dry air cured and One Sucker tobaccos. The tobacco material may comprise or consist of reconstituted tobacco, tobacco lamina, paper reconstituted tobacco, extruded tobacco, bandcast reconstituted tobacco, or a combination of reconstituted tobacco and another form of tobacco, such as tobacco lamina or granules. In some embodiments, the aerosol generating material may comprise more than one botanical material. This provides the advantage that the consumer tastes different botanical materials.

[0065] In some embodiments, the aerosol generating material comprises at least about 10 wt% of the botanical material. In some embodiments, the aerosol generating material comprises at least 40 wt%, at least about 50 wt%, at least about 60 wt%, at least about 75 wt%, at least about 95 wt%, at least about 99 wt% of the botanical material. In some embodiments, the aerosol generating material substantially consists of the botanical material.

[0066] In some embodiments, the aerosol generating material comprises at most about 10 wt% of the botanical material. In some embodiments, the aerosol generating material does not comprise a botanical material. In some embodiments, the aerosol generating material comprises at most about 60 wt%, at most about 75 wt%, at most about 80 wt%, at most about 95 wt%, at most about 99 wt% of the botanical material. For example, the botanical material may be present in an amount of about 50%, 60%, 70%, 80%, or 90% by weight of the aerosol generating material. The botanical material maybe present in an amount of from about 50 to about 80% by weight of the aerosol generating material. The botanical material content may be selected to provide a positive flavour to the user and to provide a suitable texture in the aerosol generating material. The botanical content affects the elasticity and the tensile strength in the aerosol generating material, the first and / or second aerosol generating material. The botanical material may be a particulate or granular material. In some embodiments, the botanical material is a powder or may be ground. Alternatively, or in addition, the botanical material may comprise strips, strands or fibres of botanical material. For example, the botanical material may comprise particles, granules, fibres, strips and / or strands of botanical material. In some embodiments, the botanical material consists of particles or granules of botanical material. Botanical material particles provide the benefit that the particle size distribution and the resulting physical characteristics of the sheet as described herein may be more easily controlled.

[0067] In embodiments in which the botanical material is a particulate botanical material, each particle of the particulate botanical material may have a maximum dimension. As used herein, the term “maximum dimension” refers to the longest straight line distance from any point on the surface of a particle of botanical material, or on a particle surface, to any other surface point on the same particle of tobacco, or particle surface. The maximum dimension of a particle of particulate botanical material may be measured using scanning electron microscopy (SEM).

[0068] In some embodiments, the maximum dimension of each particle of botanical material is up to about 500 pm, up to about 450 pm, up to about 400 pm, or up to about 350 pm. In some embodiments, the maximum dimension of each particle of botanical material is at least about 320 pm, up to about 350 pm, up to about 400 pm, or up to about 500 |um. In some embodiments, the maximum dimension of each particle of botanical material is about 320 to 350 pm.

[0069] In some embodiments, the aerosol generating material may comprise a portion of particles of the botanical material having the maximum dimension of at most about 80 pm. In some embodiments, the portion of particles is 10% of the total composition of botanical material in the aerosol generating material. It has been found that embodiments wherein the aerosol generating material comprises a portion of at most 10% particles of the botanical material having the maximum dimension of at most about 80 pm enjoys the advantage of an increased tensile strength. D90 may be selected based on the density of the aerosol generating material. For example, if the lower the density, the lower D90 that may be used.

[0070] The inventors have found that a small particle size distribution (PSD) is associated with a less rough surface of the sheet or shredded sheet, as described herein. It is though that a smaller PSD may be manipulated and flattened by the rollers to produces a more homogenous and smoother surface.

[0071] In addition, the inventors have found that the botanical material particle size affects the tensile strength. A small PSD is associated with a higher tensile strength, and higher density of the aerosol generating material. The D90 may be selected to optimise the tensile strength of the aerosol generating material. The tensile strength of the material maybe affected by the amount (wt%) and / or type of botanical material. The inventors have found that the D90 may therefore be selected to maintain the desired tensile strength of the aerosol generating material, whilst still altering the amount and / or type of botanical material.

[0072] The inventors have found that the particle size distribution (D90) may be controlled to achieve the desired area density of the aerosol-generating material, and the sheet, shredded sheet or product produced therefrom. The area density of the material may be measured in GSM (grams per square metre or g / m2). For example, lower particle size distributions (D90) are associated with higher area densities. When the aerosolgenerating material is incorporated into an article for use in a non-combustible aerosol provision system, this higher area density may decrease the fill-value of the botanical material. A population of particles of the botanical material may have a particle size distribution (D90) of at least about too pm. In some embodiments, a population of particles of the botanical material has a particle size distribution (D90) of at least about 200 pm, of at least about 250, of at least about 300 pm, of at least about 320 pm. In some embodiments, a population of particles of the botanical material has a particle size distribution (D90) of at most about 500 pm, of at most about 450 pm, of at most about 400 pm, of at most about 350 pm. In some embodiments, a population of particles of the botanical material has a particle size distribution (D90) of about 320 to 350 pm. A particle size and shape analyser, such as a Camsizer may be used to measure the particle size distribution, and sieve analysis may be used to determine the particle size distribution of the particles of botanical material.

[0073] In some embodiments, the sheet or shredded sheet has a homogenous or substantially homogenous thickness. As used herein the term thickness is defined by the distance between the first and second surfaces of the sheet or shredded sheet.

[0074] In some embodiments, the term homogenous thickness may refer to a consistent thickness across an area of the aerosol generating material. In some embodiments, the thickness may not vary by more than about 10% over an area of the sheet. In some embodiments, the thickness may not vary by more than about 20%, about 15%, about 10%, about 8% or more than about 5% over an area of the sheet. In some embodiments, said area of the sheet or shredded sheet is at least a portion of the sheet or shredded sheet. In some embodiments, the portion of the sheet maybe at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 99% of the area of the sheet or shredded sheet.

[0075] In some embodiments the thickness of the aerosol generating material is about 0.15 to about 0.35 mm. In some embodiments, the thickness of the aerosol-generating material is about 0.18 to about 0.32 mm, about 0.2 to about 0.3 mm, or about 0.24 to about 0.28. The thickness of the sheet can be determined using the Guobiao standards method outlined in “GB / T 451.3 Paper and board-Determination of thickness”. In some embodiments, the thickness of the sheet or shredded sheet can be determined according to ISO 534 - Paper and board, which relates to the determination of thickness, density and specific volume. In some embodiments, the thickness of the sheet or shredded sheet can be determined according to ISO 3402-Tobacco and tobacco products, which relates to the atmosphere for conditioning and testing. The thickness may be selected to provide a suitable malleability and tensile strength.

[0076] The inventors have established that if the sheet or shredded sheet of aerosol generating material is too thick, then heating efficiency can be compromised. This can adversely affect power consumption in use, for instance the power consumption for release of flavour from the aerosol generating material. Conversely, if the aerosol generating material is too thin, it can be difficult to manufacture and handle; a very thin material can be harder to cast and may be fragile, compromising aerosol formation in use. The improved homogeneity of the thickness of the sheet provides the advantage that the sheet or shredded sheet is consistent in thickness, which results in improved consistency of flavour delivery. The thickness of the sheet or shredded sheet is also more consistent during manufacturing of the article, which makes machining the final product faster and cheaper.

[0077] Without wishing to be bound by a singular theory, when the material is rolled, the thickness is easily controlled by varying the distance between the rollers. In addition, more than one rolling press may be used to incrementally reduce the thickness and provide tight control over the thickness of the sheet or shredded sheet.

[0078] The homogeneity of the rolled sheet or shredded sheet is improved compared to other methods of making aerosol generating materials. For example, a known method to make an aerosol generating material, commonly known as “band casting”, includes producing a slurry which is formed into a layer which is flattened using a blade and dried. The use of rollers flattens the material consistently, whereas the use of a blade is known to provide a textured or rough surface. The thickness of the material produced in this method is also inconsistent.

[0079] Figure 1 shows a graph showing the thickness of the sheet along a length of the sheet. The material is passed through a micrometer and the thickness is repeatedly measured.

[0080] Sheet 1 is a sheet of aerosol generating material produced using the “band casting method” and Sheet 2 is a sheet of the claimed aerosol generating material. It is clear that the thickness of Sheet 2 is more homogeneous and consistent than sheet 1. The line of best fit (linear regression fit) of the data of Sheet 2 has a lower gradient than that of Sheet 1. This shows an improved consistency and lower variance of the thickness of the sheet over time and across the measured area of the sheet. The thickness of the sheet or shredded sheet is also thought to have a bearing on its area density and mass:volume ratio of the material. That is to say, increasing the thickness of the sheet or shredded sheet may decrease the area density of the sheet or shredded sheet. Conversely, decreasing the thickness of the sheet or shredded sheet may increase the area density of the sheet or shredded sheet. Thus, the more homogeneous the thickness, the more homogeneous the density. For the avoidance of doubt, where reference is made herein to area density, this refers to an average area density calculated for a given strip, strand, piece or sheet of the aerosol generating material, the area density calculated by measuring the surface area and weight of the given strip, strand, piece or sheet of aerosol generating material.

[0081] It has been observed that a sheet or shredded sheet having a thickness of at least about from about 0.15 mm to about 0.35 mm, along with an area density of from about 150 g / m2to about 200 g / m2is less liable to tear, split or become otherwise deformed during its manufacture. A thickness of at least about too pm may have a positive effect on the overall structural integrity and strength of sheet or shredded sheet. For example, it may have a good tensile strength and thus be relatively easy to process the material. Advantageously, the inventors have found that a homogenous tensile strength reduces the likelihood of splitting or deforming at a particular location of lower thickness or density.

[0082] In some embodiments, the sheet or shredded sheet has a homogenous or substantially homogenous area, bulk and / or volume density. In some embodiments, the term homogenous density may refer to a consistent area and / or volume density across an area of the aerosol generating material. In some embodiments, the area and / or volume density may not vary by more than 10% over an area of the sheet. In some embodiments, the area and / or volume density may not vary by more than 8% or more than 5% over an area of the sheet. In some embodiments, said area of the sheet or shredded sheet is at least a portion of the sheet or shredded sheet. In some embodiments, the portion of the sheet maybe at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 99% of the area of the sheet or shredded sheet. Advantageously, the claimed aerosol generating material has a homogenous volume density or area density. This results in a consistent distribution of the components of the aerosol generating material. This means that the homogeneous density contributes to the provision of a consistent flavour delivery to the user.

[0083] In some embodiments, the sheet or shredded sheet of aerosol-generating material has an area density of from about too g / m2to about 300 g / m2, or from about 150 to about 210 g / m2. The sheet or shredded sheet may have an area density of from about 110 g / m2to about 280 g / m2, from about 120 g / m2to about 260 g / m2, from about 130 g / m2to about 420 g / m2or from about 140 g / m2to about 220 g / m2. In some embodiments, the sheet or shredded sheet has an area density of from about 130 g / m2to about 290 g / m2, from about 140 g / m2to about 180 g / m2, from about 160 g / m2to about 210 g / m2.

[0084] The average volume density or grammage of the sheet or shredded sheet of aerosolgenerating material may be calculated from the thickness of the sheet and the area density of the sheet. In some embodiments, average volume density or grammage may be greater than about 0.4 g / cm3, about 0.6 g / cm3orabout 0.7 g / cm3. jnsome embodiments, the average volume density is from about 0.4 g / cm3 to about 1 g / cm3, from about 0.4 g / cm3 to about 0.9 g / cm3, from about 0.5 g / cm3 to about 0.8 g / cm3, from about 0.6 g / cm3 to about 0.8 g / cm3Or from about 0.7 g / cm3 to about 0.8 g / cm3. In some embodiments, the average volume density is from about 0.72 g / cm3 to about 0.80 g / cm3,

[0085] The aerosol generating material has a lower density compared to other aerosol generating materials. As a result of this lower density, the rod is lighter, and therefore easier to handle and stored.

[0086] The tensile strength of the sheet or shredded sheet may be associated with the thickness and area density of the sheet or shredded sheet. A thicker sheet or shredded sheet may have a higher tensile strength than a thinner sheet or shredded sheet. A sheet or shredded sheet with a greater density may have a higher tensile strength.

[0087] The sheet or shredded sheet may have a tensile strength of at least 3 N / 15 mm.

[0088] The inventors have found that, where the sheet or shredded sheet has a tensile strength below 3 N / 15 mm> the sheet or shredded sheet is likely to tear, break or otherwise deform during its manufacture and / or subsequent incorporation into an article for use in a non-combustible aerosol provision system. Tensile strength may be measured using ISO 1924:2008. The sheet or shredded sheet may have a tensile strength of at least 4 N / 15 mm. This is advantageous because common machinery used in processing the aerosol generating material often has a limit for use with materials with at least 4 N / 15 mm. In some embodiments, the sheet or shredded sheet may have a tensile strength of at most 20 N / 15 mm.

[0089] The sheet or shredded sheet may have a more consistent tensile strength across the sheet or shredded sheet. This reduces the likelihood of breakage when the sheet or shredded sheet is manipulated, for example during manufacturing, packaging or storage. If the tensile strength is too low the aerosol-generating material may be relatively brittle. It is particularly advantageous when the aerosol generating material is incorporated into an article for use in a non-combustible aerosol-provision device. As a result of the homogeneous density and therefore tensile strength, the strips are able to maintain their integrity when the aerosol generating material is formed into an article, or when an aerosol generator is inserted into the aerosol generating material, thus improving the ease by which the aerosol generator maybe inserted into the material.

[0090] The sheet or shredded sheet of aerosol-generating material may have a burst strength of at least about 75 g, at least about too g or at least about 200 g. In some embodiments, the burst strength of the sheet or shredded sheet of aerosol-generating material is at least 150 g.

[0091] In some embodiments, the sheet or shredded sheet has a homogeneous roughness. In some embodiments, the term homogenous roughness refers to mean surface roughness, for example calculated by measuring the average of surface heights and depths across a surface of the sheet or shredded sheet. In some embodiments, the term homogenous roughness refers to a lower average surface roughness. In some embodiments, said area of the sheet or shredded sheet is at least a portion of the sheet or shredded sheet. In some embodiments, the portion of the sheet may be at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 99% of the area of the sheet or shredded sheet.

[0092] In some embodiments the aerosol-generating material in the form of a sheet or shredded sheet comprising a first surface and a second surface, and the first and second surfaces have substantially the same surface roughness. Additionally, the surface roughness is homogenous over the entire area of the surface of the sheet.

[0093] Surface roughness maybe measured in a plurality of methods. Average roughness (Ra), Average Maximum Height of the Profile (Rz) and Mean Spacing of Profile Irregularities

[0094] (RSm) maybe measured according to ISO Standard 4287. Figures 2 to 4 show graphs to show the average Ra, Rz, and RSm of the first and second surfaces of sheet 1 (aerosol generating material in the form of a sheet made using a band casting process) and sheet 2 (the claimed aerosol generating material in the form of a sheet).

[0095] Figure 2 shows that the difference in Ra between the first and second surface of sheet 1 is much greater than sheet 2. In other words, the first and second surface of sheet 2 are more homogenous and similar in roughness than the first and second surfaces of sheet 1. In addition, the Ra of both the first and second surfaces are lower (ie: less rough and more smooth) than the first surface of sheet 1.

[0096] Likewise, Figures 3 and 4 show the same trend for Rz and RSm respectively.

[0097] In some embodiments, the first and / or second surfaces have an average roughness (Ra) according to ISO Standard 4287 of from about 10 pm to about 30 pm. In some embodiments, the first and / or second surfaces have an average roughness (Ra) according to ISO Standard 4287 of from about 15 pm to about 20 pm.

[0098] The roughness of the surface may be generated from the surface of the rollers, which transfers its texture onto the surface(s) of the aerosol generating material.

[0099] The inventors have also found that the area density of the sheet or shredded sheet of aerosol-generating material influences the roughness of the first and second surfaces of the sheet or shredded sheet. By changing the area density, the roughness of the first and / or second surfaces can be tailored. For example, increasing the area density, is associated with a smaller granulometry, which results in a smooth surface. This may decease the roughness of the first and second surfaces. Decreasing the area density increases the roughness of the first and second surfaces. As the surface roughness is more homogeneous, the sheet or shredded sheet varies in thickness less and is smoother across at least one surface. The inventors have found that this reduces disruption airflow over the at least one surface and improves airflow, and therefore flavour delivery and user experience, compared to an aerosol generating material that has not been manufactured in the method described herein. The first and / or second surfaces of the sheet or shredded sheet may be relatively uniform (e.g. they maybe relatively smooth).

[0100] In some embodiments, both the first and second surfaces are relatively smooth. This further improves airflow, as both sides of the sheet or shredded sheet will disrupt the airflow in a more similar way. This improves the consistency of the aerosol generated from the material, and provides improved flavour delivery to the user.

[0101] The sheet or shredded sheet further enjoys the benefit that the less rough surfaces come together more easily in the article. Without wishing to be bound by a particular reason, it is thought that as the surfaces are less rough, they can move past each other and fit into the article more easily. This improves the packing density of the aerosol generating material. These improvements are particularly apparent compared to other aerosol generating materials in which the first and second surfaces are not homogenous. For example, the band casting method to make aerosol generating materials results in a material with a first surface that is rougher than the other second surface. This is because a blade is used to flatten a slurry on a mesh before it is dried. Thus, the claimed aerosol generating material enjoys these advantages over such band cast materials.

[0102] The aerosol generating material may have a packing density of between about 400 mg / cm3 and about 900 mg / cm3 within the aerosol-generating section. A packing density higher than this may make it difficult to insert the aerosol-generator of the aerosol provision device into the aerosol-generating material and increase the pressure drop. A packing density lower than 400 mg / cm3 may reduce the rigidity of the article. Furthermore, if the packing density is too low, the aerosol-generating material may not effectively grip the aerosol-generator of the aerosol provision.

[0103] The smoothness of the first and second surfaces may be influenced by a number of factors, such as their area density and the nature of the components that make up the aerosol generating material, for example the particle size of the botanical material. In addition, the rollers used in the production the aerosol generating material flatten and smooth the surface of the material. In some embodiments, the sheet or shredded sheet has a homogeneous permeability or air permeability.

[0104] As used herein, permeability refers to the flow of air, aerosol or a mixture of air and aerosol, which may be generated by the aerosol-generating material as it is heated by the aerosol generator. As used herein, the term air permeability refers to the time required for a known volume of air, aerosol or a mixture of air and aerosol, to pass through a known area of the sheet. Thus, a lower air permeability is associated with a lower permeability of the aerosol generating material.

[0105] In some embodiments, a homogeneous permeability or air permeability refers to a more consistent permeability or air permeability across the sheet or shredded sheet of aerosol generating material or area of the sheet or shredded sheet. In some embodiments, said area of the sheet or shredded sheet is at least a portion of the sheet or shredded sheet. In some embodiments, the portion of the sheet may be at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 99% of the area of the sheet or shredded sheet.

[0106] In some embodiments, the air permeability of the aerosol generating material is at most about 60, at most about 50, at most about 45, at most about 40 or at most about 3 s / too cm3, in some embodiments, the air permeability of the aerosol generating material is at least about 5, at least about 10, at least about 15, or at least about 20 s / too cm3, in some embodiments, the air permeability of the aerosol generating material is between 5 and 40 s / 100 cm3. Air permeability maybe measured using a Gurley Precision Instruments Densometer and / or a Gurley Precision Instruments

[0107] Porosity Test Plate.

[0108] The aerosol generating material enjoys the benefit of a lower air permeability. A lower air permeability is associated with a higher permeability of the aerosol generating material. A lower air permeability has a positive impact on aerosol generation, as more air or aerosol passes though the material in a given time. This enables more of the aerosol to be generated and to pass to the user.

[0109] In addition, lower air permeability or higher permeability is linked to an improved pressure drop, and therefore an improved user experience. In addition, a more homogenous air permeability or permeability is associated with an improved pressure drop across the area of the material, providing a more consistent user experience, and consistent delivery of flavour.

[0110] The inventors consider that the lower density of the material is associated with the improved air permeability. Without wishing to be bound by a singular reason, it is thought that the lower density results in a lower porosity and this in turn enables more air or aerosol to pass through the material.

[0111] Figure 5 shows air permeability data of Sheet 1 (aerosol generating material in the form of a sheet made using a band casting process) and Sheet 2 (the claimed aerosol generating material in the form of a sheet). This shows the time required for too cm3 of air to pass through a known area of the sheet. The time required for the air to pass through is lower for Sheet 2 than Sheet 1. This illustrates the improved air permeability of the claimed aerosol generating material.

[0112] In some embodiments, the visual appearance of the sheet is homogeneous. For example, the sheet may have a more uniform appearance, texture or colouration across an area of its surface or the surface. In some embodiments, the first surface may have a similar appearance to the second surface of the sheet. For example, the first and second surfaces may have a similar appearance, texture or colouration to one another. In addition, the visual appearance may be homogeneous across the entire area of one or each surface.

[0113] For example, the sheet produced using rollers will have a homogenous texture. Other sheets, for example formed using a band casting method, have different surface roughness on the first and second surfaces.

[0114] This provides the advantage that the appearance of the sheet is improved, which results in an improved perception of the quality of the material.

[0115] Figure 6 is a graph of data collected from a light intensity machine. The light intensity machine measures the amount of light that may pass through the material on strip cut maker, before the material is cut or sliced. Figure 7 shows a table of data from Figure 6. Sheet 1 is a sheet of aerosol generating material produced using the “band casting method” and Sheets 2 and 3 are a sheet of the claimed aerosol generating material. The standard deviation of the light intensity data of Sheets 2 and 3 are lower than that of Sheet 1. This indicates that the variance of the data is less and that Sheets 2 and 3 are more homogeneous than sheet 1. Figures 6 and 7 also show the light permeability of the sheets. Light permeability is linked to the thickness and density of the sheet. Figure 6 shows that sheets 2 and 3 (comprising the claimed aerosol generating material) have a more consistent and homogeneous light permeability and thus more consistent thickness and density compared to sheet 1 (a band cast sheet).

[0116] In another aspect of the invention, an article for use with a non-combustible aerosolprovision system is provided comprising the aerosol generating material.

[0117] An article or consumable is an article comprising or consisting of the aerosolgenerating material, part or all of which is intended to be consumed during use by a user. An article may comprise one or more other components, such as an aerosolgenerating material storage area, an aerosol-generating material transfer component, an aerosol generation area, a housing, a wrapper, a mouthpiece, a filter and / or an aerosol-modifying agent. A consumable may also comprise an aerosol generator, such as a heater, that emits heat to cause the aerosol-generating material to generate aerosol in use. The heater may, for example, comprise combustible material, a material heatable by electrical conduction, or a susceptor.

[0118] As used herein, the term “delivery system” is intended to encompass systems that deliver at least one substance to a user, and includes: combustible aerosol provision systems, such as cigarettes, cigarillos, cigars, and tobacco for pipes or for roll-your-own or for make-your-own cigarettes (whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco, tobacco substitutes or other smokable material); non-combustible aerosol provision systems that release compounds from an aerosol-generating material without combusting the aerosol-generating material, such as electronic cigarettes, tobacco heating products, and hybrid systems to generate aerosol using a combination of aerosol-generating materials; and aerosol-free delivery systems that deliver the at least one substance to a user orally, nasally, transdermally or in another way without forming an aerosol, including but not limited to, lozenges, gums, patches, articles comprising inhalable powders, and oral products such as oral tobacco which includes snus or moist snuff, wherein the at least one substance may or may not comprise nicotine.

[0119] According to the present disclosure, a “non-combustible” aerosol provision system is one where a constituent aerosol-generating material of the aerosol provision system (or component thereof) is not combusted or burned in order to facilitate delivery of at least one substance to a user. In some embodiments, the delivery system is a non-combustible aerosol provision system, such as a powered non-combustible aerosol provision system.

[0120] In some embodiments, the non-combustible aerosol provision system is an electronic cigarette, also known as a vaping device or electronic nicotine delivery system (END), although it is noted that the presence of nicotine in the aerosol-generating material is not a requirement.

[0121] In some embodiments, the non-combustible aerosol provision system is an aerosolgenerating material heating system, also known as a heat-not-burn system. An example of such a system is a tobacco heating system.

[0122] In some embodiments, the non-combustible aerosol provision system is a hybrid system to generate aerosol using a combination of aerosol-generating materials, one or a plurality of which may be heated. Each of the aerosol-generating materials may be, for example, in the form of a solid, liquid or gel and may or may not contain nicotine. In some embodiments, the hybrid system comprises a liquid or gel aerosol-generating material and a solid aerosol-generating material. The solid aerosol-generating material may comprise, for example, tobacco or a non-tobacco product.

[0123] Typically, the non-combustible aerosol provision system may comprise a non- combustible aerosol provision device and a consumable for use with the non- combustible aerosol provision device.

[0124] In some embodiments, the disclosure relates to consumables comprising aerosol- generating material and configured to be used with non-combustible aerosol provision devices. These consumables are sometimes referred to as articles throughout the disclosure.

[0125] In some embodiments, the non-combustible aerosol provision system, such as a noncombustible aerosol provision device, may comprise a power source and a controller. The power source may, for example, be an electric power source or an exothermic power source. In some embodiments, the exothermic power source comprises a carbon substrate which may be energised so as to distribute power in the form of heat to an aerosol-generating material or to a heat transfer material in proximity to the exothermic power source. In some embodiments, the non-combustible aerosol provision system may comprise an area for receiving the consumable, an aerosol generator, an aerosol generation area, a housing, a mouthpiece, a filter and / or an aerosol-modifying agent.

[0126] In some embodiments, the consumable for use with the non-combustible aerosol provision device may comprise aerosol-generating material, an aerosol-generating material storage area, an aerosol-generating material transfer component, an aerosol generator, an aerosol generation area, a housing, a wrapper, a filter, a mouthpiece, and / or an aerosol-modifying agent.

[0127] In some embodiments, the aerosol generating material is provided in an aerosol generating section. In some embodiments, the aerosol generating material is in the form of a shredded sheet.

[0128] The invention provides the advantage that the aerosol generating material provides an improved pressure drop across the aerosol-generating section. Advantageously, compared to other aerosol generating materials, the aerosol generating material according to the present disclosure may have a lower mass with the same pressure drop when incorporated into an aerosol-generating article. Without wishing to be bound by any particular theory, the less rough surface may provide increased airflow around the aerosol generating material, thereby increasing the pressure drop across the aerosol generating material and / or the section comprising said material. The pressure drop is also associated with the improved permeability of the material. In some embodiments, the pressure drop across the aerosol-generating section is about too to about 500 mmWg. In some embodiments, the pressure drop across the aerosol- generating section is about too to about 200 mmWg about 200 to about 400 mmWg, or about 300 to about 350 mmWg.

[0129] In some embodiments, the pressure drop across the article is about 40 to about 120 mmWg, about 50 to about too mmWg, about 60 to about 90 mmWg.

[0130] When in use, the article may exhibit a pressure drop of from about 15 to about 40 mm H20. In some embodiments, the aerosol-generating section exhibits a pressure drop across the aerosol-generating section of from about 15 to about 30 mm H20.

[0131] In some embodiments, the aerosol generation section is at most about 34 mm, at most about 28 mm, at most about 25 mm, at most about 20 mm, at most about 16 mm, at most about 12 mm. In some embodiments, the article at most about 34 mm, at most about 28 mm, at most about 25 mm, at most about 20 mm, at most about 16 mm, at most about 12 mm or at most 10 mm.

[0132] In an exemplary embodiment, Figure 9 is a perspective view of an article 1 for use in an aerosol delivery system. Figure 10 is a side-on cross sectional view of the article 1.

[0133] The article 1 comprises a mouthpiece 2, and an aerosol-generating section 3, connected to the mouthpiece 2. In the present example, the aerosol-generating section 3 comprises the aerosol-generating material. The aerosol generating material maybe in the form of a sheet or shredded sheet in the article. The article 1 comprises a downstream end 2b and an upstream end 2a distal from the downstream end 2b.

[0134] In the present example, the aerosol-generating material is circumscribed by a wrapper 5. In the present example, the wrapper 5 is a moisture impermeable wrapper. The wrapper 5 also circumscribes a plug 4. In some embodiments, the wrapper is paper, but may be made of alternative materials, such as aluminium.

[0135] The mouthpiece 2 includes a cooling section 6, also referred to as a cooling element, positioned immediately downstream of and adjacent to the source of aerosol- generating material 3. In the present example, the cooling section 6 is in an abutting relationship with the source of aerosol-generating material. The mouthpiece 2 also includes, in the present example, a body of material 7 downstream of the cooling section 6, and a hollow tubular element 8 downstream of the body of material 7, at the mouth end of the article 1. In another aspect of the invention, a method for producing the aerosol generating material is provided comprising the steps of: forming a first composition comprising a first binder and an aerosol former; forming a second composition comprising a botanical material, a filler and optionally a second binder; combining the first composition and the second composition to form a mixture of the first composition and the second composition; extruding the mixture; and rolling the extruded mixture using at least one roller to form the aerosol generating material.

[0136] The aerosol generating material maybe produced by any suitable method, however, the method described herein affords particular advantages.

[0137] Figure 8 illustrates an exemplary embodiment of the method to manufacture the aerosol generating material. A first composition comprising a binder and an aerosol former and a second composition comprising botanical material, filler and optionally a second binder are formed and mixed. In the subsequent step the first composition and the second composition are mixed and extruded. Following this, the extruded mixture of the first composition and the second composition is rolled and then may be dried to form a sheet of aerosol-generating material. The sheet may then be shredded in order to make the aerosol-generating material, which may then be incorporated into a consumable for a non-combustible aerosol delivery system. Optionally, the sheet is shredded.

[0138] In some embodiments, the first composition, also known as the “wet mixture”, comprises an aerosol former or humectant and a binder. The first composition may also comprise other liquids or suspensions disclosed herein.

[0139] In some embodiments, the first composition may comprise an aerosol former. The aerosol former comprises one or more constituents capable of forming an aerosol. The aerosol former comprises one or more of glycerine, glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl suberate, triethyl citrate, triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate. In some embodiments, the aerosol former is glycerine, glycerol or propylene glycol.

[0140] In some embodiments, the first composition may comprise a first binder. The binder is arranged to bind the components of the first composition. Once combined with the second composition, the binder binds the components of the first and second compositions to form the aerosol-generating material. The first composition can comprise more than one binder. In such embodiments, the binders in the first composition can be the same or different.

[0141] The binder may be selected from one or more compounds selected from the group comprising alginates, pectins, starches (and derivatives), celluloses (and derivatives), gums, silica or silicones compounds, clays, polyvinyl alcohol and combinations thereof. For example, in some embodiments, the binder comprises one or more of alginates, pectins, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethylcellulose (CMC), pullulan, xanthan gum, guar gum, carrageenan, agarose, acacia gum, fumed silica, PDMS, sodium silicate, kaolin and polyvinyl alcohol. In some cases, the binder comprises alginate and / or pectin or carrageenan. In some embodiments, the binder comprises CMC.

[0142] The binder maybe selected to provide specific properties to the first or second composition, the mixture of the first and second composition, and / or the aerosol generating material. The viscosity of binder may be dependent on the type of binder, the concentration and the temperature. In general, as the temperature increases, the viscosity decreases and as the concentration increases, the viscosity increases. The binder may comprise or consist of a low, medium or high viscosity binder. For example, a low viscosity binder is commonly used in "thin" aqueous solutions. A medium viscosity binder may be used to make solutions that resemble a syrup. A high viscosity binder can be used to make a mixture, which resembles a cream or lotion.

[0143] A high viscosity binder has a viscosity of about 7000 to about 10000 centipoise (cPs).

[0144] For example, the high viscosity binder may have 9620 cPs. A medium viscosity binder has a viscosity of about 3000 to about 7000 cPs. A low viscosity binder has a viscosity of about o to about 3000 cPs. For example, the low viscosity binder may have a viscosity of abour 2315 cPs.

[0145] The binder may comprise or consist of CMC. It has been unexpectedly found that the selection of the binder, and in particular the viscosity of the binder, provides a specific consistency and texture of the material. For example, a higher viscosity is associated with easier processing in the machinery, better machine runnability, and also easier formation of a sheet or shredded sheet. For example, the material maybe less sticky and less breakable. This may also improve the texture of the aerosol generating material. The advantage is particularly apparent in embodiments in which the binder comprises or consists of CMC.

[0146] In a specific example, the binder is CMC, such as Gumix K-1500 F, which has a viscosity of 9620 cPs. This is a high viscosity binder, and the improved texture has been noted. In another specific example, the binder is CMC, such as Gumix K-500, which has a viscosity of 2315 cPs.

[0147] In some embodiments, the first composition may comprise a nicotine component. By “nicotine component” is meant refer to any suitable form of nicotine (e.g., free base or salt) for providing oral absorption of at least a portion of the nicotine present.

[0148] Typically, the nicotine component is selected from the group consisting of nicotine free base and a nicotine salt. In some embodiments, the nicotine component is nicotine in its free base form, which easily can be adsorbed in for example, a microcrystalline cellulose material to form a microcrystalline cellulose-nicotine carrier complex. See, for example, the discussion of nicotine in free base form in US Pat. Pub. No. 2004 / 0191322 to Hansson, which is incorporated herein by reference.

[0149] In some embodiments, at least a portion of the nicotine component can be employed in the form of a salt. Salts of nicotine can be provided using the types of ingredients and techniques set forth in US Pat. No. 2,033,909 to Cox et al. and Perfetti, Beitrage Tabakforschung Int., 12: 43-54 (1983), which are incorporated herein by reference.

[0150] Additionally, salts of nicotine are available from sources such as Pfaltz and Bauer, Inc. and K&K Laboratories, Division of ICN Biochemicals, Inc. Typically, the nicotine component is selected from the group consisting of nicotine free base, a nicotine salt such as hydrochloride, dihydrochloride, monotartrate, bitartrate, sulfate, salicylate, and nicotine zinc chloride.

[0151] The nicotine salt maybe formed using a pH modifier, which maybe included in the first composition. The pH modifier may comprise pH adjusters or buffering agents.

[0152] Examples of pH modifiers that can be used include, but are not limited to, metal hydroxides (e.g., alkali metal hydroxides such as sodium hydroxide and potassium hydroxide), and other alkali metal buffers such as metal carbonates (e.g., potassium carbonate or sodium carbonate), or metal bicarbonates such as sodium bicarbonate, organic or non-organic acids, including benzoic acid, lactic acid, ascorbic acid, acetic acid, and the like. In some embodiments, the pH modifier is selected from the group of benzoic acid, lactic acid, ascorbic acid, and acetic acid.

[0153] Non-limiting examples of suitable buffers include alkali metals acetates, glycinates, phosphates, glycerophosphates, citrates, carbonates, hydrogen carbonates, borates, or mixtures thereof.

[0154] In some embodiments, at least a portion of the nicotine can be in the form of a resin complex of nicotine, where nicotine is bound in an ion-exchange resin, such as nicotine polacrilex, which is nicotine bound to, for example, a polymethacrylic acid, such as

[0155] Amberlite IRP64, Purolite C115HMR, or Doshion P551. See, for example, US Pat. No.

[0156] 3,901,248 to Lichtneckert et al., which is incorporated herein by reference. Another example is a nicotine polyacrylic carbomer complex, such as with Carbopol 974P. In some embodiments, nicotine may be present in the form of a nicotine polyacrylic complex.

[0157] In some embodiments, the first composition, the aerosol generating material and / or compositions of the disclosure can be characterized as free of any nicotine component (e.g., any embodiment as disclosed herein maybe completely or substantially free of any nicotine component). By “substantially free” is meant that no nicotine has been intentionally added, beyond trace amounts that may be naturally present in e.g., a botanical material. For example, certain embodiments can be characterized as having less than 0.001% by weight of nicotine, or less than 0.0001%, or even 0% by weight of nicotine, calculated as the free base. In some embodiments, water is added to the first composition to form a suitable consistency. The first composition maybe in a liquid, gel, slurry or suspension phase. Water is added to provide a suitable consistency for mixing, extrusion and rolling processes.

[0158] In some embodiments, the water content of the first mixture is about 20 to about 60%, about 25 to about 50%, about 30 to about 40%, about 28 to 33%, or about 33 to 37%. In some embodiments, the water content of the first mixture is about 28%. In some embodiments, the water content of the first mixture is about 33%. In some embodiments, the water content of the first mixture is about 37%.

[0159] The second composition, also known as the “dry mixture”, comprises a botanical material, a filler and optionally a second binder. The second composition may also comprise other solids or gels disclosed herein. The second composition may be in the solid phase.

[0160] In some embodiments, the second composition comprises a filler. The filler is generally a non-tobacco component, that is, a component that does not include ingredients or components originating from tobacco. The filler may comprise one or more inorganic filler materials, such as calcium carbonate, perlite, vermiculite, diatomaceous earth, colloidal silica, magnesium oxide, magnesium sulphate, magnesium carbonate, and suitable inorganic sorbents, such as molecular sieves. The filler may be a non-tobacco fibre such as wood fibre or pulp or wheat fibre. The filler can be a material comprising cellulose or a material comprises a derivate of cellulose. The filler component may also be a non-tobacco cast material or a non-tobacco extruded material. In some embodiments, the filler is cellulosic material, cellulose or CMC. In some embodiments, the filler is essentially composed or consists of cellulose.

[0161] In some embodiments, the filler is inert and unreactive. In some embodiments the filled is tasteless, and does not contribute to the flavour or organoleptic properties of the aerosol generated. This provides the advantage that the amount and type of filler maybe selected to alter the physical properties of the aerosol generating material, but not to affect the taste profile of the aerosol or the user experience. In particular embodiments which include filler, the filler is fibrous. For example, the filler may be a fibrous organic filler material such as wood, wood pulp, hemp fibre, cellulose or cellulose derivatives. Without wishing to be bound by theory, it is believed that including fibrous filler may increase the tensile strength of the aerosol-generating material that is formed. The use of cellulose as a filler has been found to have a particularly favourable impact on the burst strength of the aerosol-generating material.

[0162] The filler may also contribute to the texture of the aerosol-generating material. For example, a fibrous filler, such as cellulose, may provide an aerosol-generating material having relatively rough first and second surfaces. Conversely, a non-fibrous, particulate filler, such as powdered chalk, may provide an aerosol-generating material having relatively smooth first and second surfaces. In some embodiments, the aerosolgenerating material comprises a combination of different filler materials. The filler may help to improve the general structural properties of the aerosol-generating material, such as its tensile strength and burst strength. In some embodiments, the second composition may comprise an optional second binder. In some embodiments of the invention, the first and the second binders are the same. In some embodiments of the invention, the first and the second binders are the different. The binder may be selected from one or more compounds selected from the group comprising alginates, pectins, starches (and derivatives), celluloses (and derivatives), gums, silica or silicones compounds, clays, polyvinyl alcohol and combinations thereof. For example, in some embodiments, the binder comprises one or more of alginates, pectins, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethylcellulose (CMC), pullulan, xanthan gum, guar gum, carrageenan, agarose, acacia gum, fumed silica, PDMS, sodium silicate, kaolin and polyvinyl alcohol. In some cases, the binder comprises alginate and / or pectin or carrageenan. In some embodiments, the binder comprises CMC.

[0163] The filler component maybe present in an amount of o to 20% by weight of the aerosol generating material, or in an amount of from 1 to 10% by weight of the aerosol generating material. For example, the filler may be present in an amount of greater than about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% by weight aerosol generating material. The filler maybe present in an amount less than about 20%, 15%, 10%, 5%, or about 2% by weight of the aerosol generating material. In some embodiments, the filler component is present in an amount of 5% by weight of the aerosol generating material, as the inventors have found that the inclusion of 5% of the filler improves the burst strength and reduces the brittle nature of the aerosolgenerating material.

[0164] The aerosol former maybe present in an amount of from about 10% to about 25% by weight of the aerosol generating material, or in an amount of from 1 to about 10% by weight of the aerosol generating material. For example, the aerosol former maybe present in an amount of about 10%, 12%, 15%, 18%, 20%, or 25% by weight of the aerosol generating material. In some embodiments, the aerosol former is present in an amount of about 15% by weight of the aerosol generating material.

[0165] The binder may be present in an amount of from about 1 to about 40% by weight of the aerosol generating material, or in an amount of from 10 to about 25% by weight of the aerosol generating material. For example, the binder maybe present in an amount of greater than about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% by weight of the aerosol generating material. The binder may be present in an amount less than about

[0166] 40%, 35%, 30%, 25%, or 20% by weight of the aerosol generating material. In some embodiments, the aerosol generating material comprises a binder content of about 10 to about 25 % by weight The amount of binder in the aerosol generating material is important as this alters the consistency of the material and mixtures. Too much binder may cause the material to be too viscous to be processed, for example by pumps and machinery.

[0167] The first and the second compositions described herein may be mixed to provide a mixture of the first composition and the second composition. The mixture of the first composition and the second composition may be formed by homogenising the first composition and the second composition. The mixture of the first composition and the second composition maybe in the form of a “dough”. Advantageously, minimal addition water, or no water at all, is required to be added to the mixture to provide a homogenous dough that is suitable for subsequent processing steps. For example, the dough may then be extruded via a die, through which a homogenous dough may suitably pass without the further addition of water or the addition of a small amount of water. The mixture of the first composition and the second composition, once formed and mixed, may be extruded using any extrusion technique or apparatus known in the art to from the aerosol-generating material. Extrusion involves the feeding of a precursor composition through an orifice to produce an extruded agglomerate. The process, which applies pressure to the precursor composition combined with shear forces, results in agglomerated structures, which may be in the form of a sheet. Extrusion may be performed using one of the main classes of extruders: screw, sieve and basket, roll, ram and pin barrel extruders. Forming the sheet structures by extrusion has the advantage that this processing combines mixing, conditioning, homogenizing and moulding of the mixture of the first composition and the second composition.

[0168] Other materials may also be added during the extrusion process, such as a base, diluent, solid aerosol forming agents, solid flavour modifiers, expansion agents and other additives known in the art. This has the advantage that the additive is evenly distributed throughout the agglomerated structures formed.

[0169] The resultant extruded mixture may then be rolled using a rolling press. As used herein, a rolling press is a device including at least one roller. In embodiments in which the rolling press comprises one roller the material maybe pressed between the roller and another substantially flat surface. Preferably, the rolling press comprises two rollers, through which the material may be moved. This flattens the material. The space between the rollers may define the thickness of the aerosol generating material.

[0170] One of the disadvantages associated with the use of extrusion to form an aerosol generating material is control of its density. For example, the mixture may expand after extrusion. The rolling process provides the advantage of flattening the material in order to control the density and thickness. Furthermore, the rolling process provides the improved homogeneity properties as described herein.

[0171] The mixing and extrusion process increases homogeneity of the composition within the material, but the rolling process has the additional and synergistic effect of additionally improving the homogeneity of the physical properties of the material. The inventors have found that extruding the mixture before the rolling process allows the process of manufacturing the aerosol generating material to be continuous because this controls the amount of material entering the rolling press. In some embodiments, the extruded material is in the form of pellets, which are then then feed into the at least one rolling press. The speed of entry into the rolling process can therefore be easily controlled.

[0172] In some embodiments, the extruded mixture maybe processed by more than one rolling press, such that the extruded mixture is rolled more than once. In some embodiments, the extruded mixture is rolled at least one, two, three or four times. In some embodiments, the extruded mixture is rolled at most one, two, three or four times.

[0173] The greater the number of rollers that are used to flatten the mixture, the more homogenous the material produced is, yielding the advantages associated with homogeneity described herein.

[0174] The rolling process also provides improved control of the thickness. For example, the use of more than one rolling press may be used to roll the material successive times, thus providing the desired thickness. This may be compared to a band casting method, wherein the thickness of the resultant material is defined by the speed of the slurry added to the apparatus and the speed of the blade that flattens it.

[0175] An exemplary rolling press is illustrated schematically in Figure 9. Rolling press 102 comprises two rollers 106. The rollers 106 have a space 103 through which the material 101 moves, flattening said material. The thickness of the material is therefore defined by the distance between the rollers in space 103.

[0176] Space 103 may be adapted to produce a sheet with the required thickness. In embodiments in which more than one roller is used, space 103 may be increasingly small in each successive roller. This results in a process that slowly flattens and decreases the thickness of the material to the required thickness. This increases homogeneity of the sheet and reduces stress forced on the material as it moves through the rolling process. In some embodiments, the rollers are about 0.5, about 0.45, about 0.4 about 0.35 about 0.3 about 0.2, about 0.25, about 0.2 or about 0.15 mm apart. In some embodiments, the rollers are at most about 0.5, at most about 0.45, at most about 0.4, at most about 0.35, at most about 0.3, at most about 0.2, at most about 0.25, at most about 0.2 or at most about 0.15 mm apart.

[0177] In some embodiments, the distance between the rollers is different in the different rolling presses. For example, the distance between the rollers maybe progressively smaller to progressively flatten the material and control its thickness.

[0178] In some embodiments, the rollers are smooth. This provides the advantage of providing a sheet with reduced roughness and increased smoothness. In embodiments in which more than one rolling press is used, the use of repeated rolling over the material can further increase smoothness and decrease roughness.

[0179] In embodiments in which the rolling press(es) comprise two rollers, both the first and the second surface of the sheet may benefit from the increased smoothness and decreased roughness. This provides the additional advantage that the first and second side of the sheet or shredded sheet may be more consistent, and have a similar smoothness.

[0180] After the rolling process, the aerosol-generating material is in the form of a sheet. The resultant sheet maybe dried using any suitable drying technique known in the art. For example, microwave, infrared, air and oven drying are suitable techniques to dry the aerosol-generating material. The temperature of the drying step may be below ioo°C, and is below 9O°C in some embodiments of the invention. The drying temperature employed maybe at most about 25°C, about 3O°C, about 4O°C, about 5O°C, about 6o°C, about 7O°C, about 8o°C, about 9O°C, or about ioo°C. The length of time of the drying step may be at most about 5, at most about 10, at most about 30, at most about 45, at most about 60, at most about 90, at most about 120, or at most about 360 minutes.

[0181] In some embodiments, the aerosol generating material comprises water. In some embodiments, the aerosol generating material comprises a water content of about o to about 15%, about 5 to about 10 or about 6.5 to about 9.5 % by weight.

[0182] The water content of the aerosol-generating material described herein may vary according to, for example, the temperature, pressure and humidity conditions at which the compositions are maintained. The water content can be determined by Karl-Fisher analysis, as known to those skilled in the art.

[0183] In some embodiments, the sheet may be shredded or sliced to form a shredded sheet. The sheet has a first and a second surface, the second surface being on the opposing face of the sheet.

[0184] The shredded sheet may comprise one or strips of the aerosol generating material. In some embodiments, the shredded sheet comprises a plurality (e.g. two or more) strips of the aerosol generating material.

[0185] Where the shredded sheet comprises a plurality of strips of material, the dimensions of each strip may by identical, similar or different. For example, the shredded sheet may comprise a first population of strips and a second population of strips, wherein the dimensions of the strips of the first population are different to the dimensions of the strips of the second population. For example, the plurality of strips may comprise a first population of strips having a first size and a second population of strips having a second size that is different to the first size. The sheet, shredded sheet or strips of material formed by shredding may be cut widthwise, for example in a cross-cut type shredding process, to define a cut length for the strips of aerosol generating material, in addition to a cut width.

[0186] In some embodiments the cut length of the sheet or shredded sheet of aerosol generating material is preferably at least 5 mm, for instance at least 10 mm, or at least

[0187] 20 mm. The cut length can be less than 60 mm, less than 50 mm, or less than 40 mm. The cut length can be from about 20 mm to about 25 mm.

[0188] In some embodiments, a plurality of strips of aerosol generating material is provided and at least one of the plurality of strips of aerosol generating material has a length greater than about 10 mm. At least one of the plurality of strips of aerosol generating material can alternatively or in addition have a length between about to mm and about 60 mm, or between about 20 mm and about 50 mm. Each of the plurality of strips of aerosol generating material can have a length between about 10 mm and about 60 mm, or between about 20 mm and about 50 mm.

[0189] In some embodiments, the substance to be delivered may be an aerosol-generating material or a material that is not intended to be aerosolised. As appropriate, either material may comprise one or more active constituents, one or more flavours, one or more aerosol-former materials, and / or one or more other functional materials.

[0190] In some embodiments, the substance to be delivered comprises an active substance.

[0191] The active substance as used herein may be a physiologically active material, which is a material intended to achieve or enhance a physiological response. The active substance may for example be selected from nutraceuticals, nootropics, psychoactives. The active substance may be naturally occurring or synthetically obtained. The active substance may comprise for example nicotine, caffeine, taurine, theine, vitamins such as B6 or B12 or C, melatonin, cannabinoids, or constituents, derivatives, or combinations thereof. The active substance may comprise one or more constituents, derivatives or extracts of tobacco, cannabis or another botanical.

[0192] In one embodiment the active substance is a legally permissible recreational drug

[0193] In some embodiments, the active substance comprises nicotine. In some embodiments, the active substance comprises caffeine, melatonin or vitamin B12.

[0194] In some embodiments, the substance to be delivered comprises a flavour.

[0195] As used herein, the terms "flavour" and "flavourant" refer to materials which, where local regulations permit, may be used to create a desired taste, aroma or other somatosensorial sensation in a product for adult consumers. They may include naturally occurring flavour materials, botanicals, extracts of botanicals, synthetically obtained materials, or combinations thereof (e.g., tobacco, cannabis, licorice (liquorice), hydrangea, eugenol, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, maple, matcha, menthol, Japanese mint, aniseed (anise), cinnamon, turmeric, Indian spices, Asian spices, herb, wintergreen, cherry, berry, red berry, cranberry, peach, apple, orange, mango, clementine, lemon, lime, tropical fruit, papaya, rhubarb, grape, durian, dragon fruit, cucumber, blueberry, mulberry, citrus fruits, Drambuie, bourbon, scotch, whiskey, gin, tequila, rum, spearmint, peppermint, lavender, aloe vera, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, khat, naswar, betel, shisha, pine, honey essence, rose oil, vanilla, lemon oil, orange oil, orange blossom, cherry blossom, cassia, caraway, cognac, jasmine, ylang- ylang, sage, fennel, wasabi, piment, ginger, coriander, coffee, hemp, a mint oil from any species of the genus Mentha, eucalyptus, star anise, cocoa, lemongrass, rooibos, flax, ginkgo biloba, hazel, hibiscus, laurel, mate, orange skin, rose, tea such as green tea or black tea, thyme, juniper, elderflower, basil, bay leaves, cumin, oregano, paprika, rosemary, saffron, lemon peel, mint, beefsteak plant, curcuma, cilantro, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, limonene, thymol, camphene), flavour enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and / or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They maybe imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, liquid such as an oil, solid such as a powder, or gas.

[0196] In some embodiments, the flavour comprises menthol, spearmint and / or peppermint.

[0197] In some embodiments, the flavour comprises flavour components of cucumber, blueberry, citrus fruits and / or redberry. In some embodiments, the flavour comprises eugenol. In some embodiments, the flavour comprises flavour components extracted from tobacco. In some embodiments, the flavour comprises flavour components extracted from cannabis.

[0198] In some embodiments, the flavour may comprise a sensate, which is intended to achieve a somatosensorial sensation which are usually chemically induced and perceived by the stimulation of the fifth cranial nerve (trigeminal nerve), in addition to or in place of aroma or taste nerves, and these may include agents providing heating, cooling, tingling, numbing effect. A suitable heat effect agent may be, but is not limited to, vanillyl ethyl ether and a suitable cooling agent may be, but not alimited to eucolyptol, WS-3. Examples

[0199] Table i depicts the components of exemplary aerosol generating materials i to 7. There was a 30% water loss during drying stage. D90 was 320-350 pm for all materials.

[0200] Table i

[0201] Table 2 depicts the components of exemplary aerosol generating materials 1 to 7. These examples have the advantage that the components are all 100% plant based. This results in a more environmentally friendly product which is desirable to the user. There was a 30% water loss during drying stage. D90 was 320-350 pm for all materials.

[0202] Table 2 Table 3 depicts physical characteristics of exemplary sheets of aerosol generating material. Advantageously, the sheets of aerosol generating material are also consistent between one other.

[0203] Table 3 Table 4 depicts physical characteristics of exemplary articles comprising the aerosol generating material. The pressure drop (PD) maybe measured across the article. In embodiments wherein the article comprises vents, the measured pressure drop may be referred to as an open pressure drop. Advantageously, the articles are also consistent between one other.

[0204] Table 4 The various embodiments described herein are presented only to assist in understanding and teaching the claimed features. These embodiments are provided as a representative sample of embodiments only, and are not exhaustive and / or exclusive. It is to be understood that advantages, embodiments, examples, functions, features, structures, and / or other aspects described herein are not to be considered limitations on the scope of the invention as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claimed invention. Various embodiments of the invention may suitably comprise, consist of, or consist essentially of, appropriate combinations of the disclosed elements, components, features, parts, steps, means, etc, other than those specifically described herein. In addition, this disclosure may include other inventions not presently claimed, but which may be claimed in future.

Claims

Claims1. An aerosol generating material, wherein the aerosol generating material is in the form of a sheet or a shredded sheet having one or more homogeneous properties selected from the group consisting of: thickness, permeability, density, surface roughness or visual appearance.

2. An aerosol generating material comprising a botanical material, wherein the aerosol generating material is in the form of a sheet or a shredded sheet having one or more homogeneous properties selected from the group consisting of: thickness, permeability, density, surface roughness or visual appearance.

3. The aerosol generating material according to claims 1 or 2, having an area density of from about 150 to about 210 g / m2.

4. The aerosol generating material according to any one of claims 1 to 3, having a volume density of from about 0.2 to about 1 g / cm3.

5. The aerosol generating material according to any one of claims 1 to 4, wherein the aerosol generating material comprises a first surface and a second surface, and wherein the first and second surfaces have substantially the same surface roughness.

6. The aerosol generating material according to claim 5, wherein the first and second surfaces have an average roughness (Ra) according to ISO Standard 4287 of from about 15 pm to about 20 pm.

7. The aerosol generating material according to any one of the preceding claims, wherein the aerosol generating material has a thickness of from about 0.15 mm to about 0.35 mm.

8. The aerosol generating material according to claim 7, wherein the thickness does not vary by more than 10% over an area of the sheet.

9. The aerosol generating material according to any one of the preceding claims, wherein the air permeability of the aerosol generating material is between 5 and 40 s / too cm3.

10. The aerosol generating material according to any preceding claim, wherein the aerosol generating material has a tensile strength of at least 3 N / ismm.

11. The aerosol generating material according to any one of claims 2 to 10, wherein the botanical material is in the form of particles.

12. The aerosol generating composition material according to claim 11, wherein the particles have a D90 of about 320 to about 350 pm.

13. The aerosol generating material according to any one of the preceding claims, wherein the aerosol generating material does not comprise tobacco material.

14. The aerosol generating material according to any one of claims 2 to 13, wherein the botanical material comprises rooibos.

15. The aerosol generating material according to any preceding claim, wherein the aerosol generating material comprises water.

16. The aerosol generating material according to claim 15, wherein the aerosol generating material comprises a water content of about 6.5 to about 9.5 % by weight.

17. The aerosol generating material according to any preceding claim, wherein the aerosol generating material comprises a botanical material content of about 50 to about 80 % by weight.

18. The aerosol generating material according to any preceding claim, wherein the aerosol generating material comprises at least one binder.

19. The aerosol generating material according to claim 18, wherein the aerosol generating material comprises a binder content of about 5 to about 25 % by weight.

20. An article for use in a non-combustible aerosol-provision system comprising an aerosol-generating section comprising the aerosol generating material according to any preceding claim.

21. The article according to claim 20, wherein the pressure drop across the article is about 40 to about 120 mmWg.

22. The article according to claim 20, wherein the pressure drop across the aerosol- generating section is about 100 to about 500 mmWg.

23. The article according to any one of claims 20 to 22, wherein the aerosol generating material is in the form of a shredded sheet.

24. A method of production of an aerosol generating material according to any preceding claim comprising the steps of: forming a first composition comprising a first binder and an aerosol former; forming a second composition comprising a tobacco material, a filler and optionally a second binder; combining the first composition and the second composition to form a mixture of the first composition and the second composition; extruding the mixture; and rolling the extruded mixture using at least one roller to form the aerosol generating material.

25. The method according to claim 24, wherein the rolling step uses four rolling presses.

26. An aerosol generating material as claimed in any one of claims 1 to 19, wherein the aerosol generating material is in the form of a sheet or a shredded sheet, wherein the aerosol generating material comprises a first surface and a second surface, and wherein the first and second surfaces have substantially the same surface roughness.

27. The aerosol generating material according to claim 26, wherein the aerosol generating material comprises a botanical material.

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