Patent Description:
Smoking articles such as cigarettes, cigars and the like burn tobacco during use to create tobacco smoke. Alternatives to these types of articles release an inhalable aerosol or vapour by releasing compounds from a substrate material by heating without burning. These may be referred to as non-combustible smoking articles or aerosol generating assemblies.

One example of such a product is a heating device which release compounds by heating, but not burning, a solid aerosolisable material. This solid aerosolisable material may, in some cases, contain a tobacco material. The heating volatilises at least one component of the material, typically forming an inhalable aerosol. These products may be referred to as heat-not-burn devices, tobacco heating devices or tobacco heating products. Various different arrangements for volatilising at least one component of the solid aerosolisable material are known.

As another example, there are e-cigarette / tobacco heating product hybrid devices, also known as electronic tobacco hybrid devices. These hybrid devices contain a liquid source (which may or may not contain nicotine) which is vaporised by heating to produce an inhalable vapour or aerosol. The device additionally contains a solid aerosolisable material (which may or may not contain a tobacco material) and components of this material are entrained in the inhalable vapour or aerosol to produce the inhaled medium.

<CIT> discloses a solid aerosol generating material comprising: about <NUM>-<NUM> wt% tobacco extract; about <NUM>-<NUM> wt% filler; about <NUM>-<NUM> wt% aerosol generating agent; and about <NUM>-<NUM> wt% binder.

<CIT> discloses a tobacco composition comprising a tobacco component in an amount of from <NUM> to <NUM>% by weight of the tobacco composition, a filler in an amount of <NUM> to <NUM>% by weight of the tobacco composition, an aerosol generating agent in an amount of from <NUM> to <NUM>% by weight of the tobacco composition, and a binder. The tobacco component comprises paper reconstituted tobacco in an amount of from <NUM> to <NUM>% by weight of the tobacco component.

<CIT> discloses a component for aerosol generation by electrical heating, the component comprising a solid aerosol generating material and a plurality of resistive wires, each of which is at least partially embedded in the solid aerosol generating material. The aerosol generating material and plurality of wires form a single unit or unitary structure. The structure may be formed from a slurry which is dried to provide the aerosol generating material in a solid form.

<CIT> discloses a heated aerosol-generating article for producing an inhalable aerosol, the heated aerosol- generating article comprising an aerosol-forming substrate, in which the aerosol-forming substrate is a homogenized tobacco material comprising tobacco and a wax having a melting point between <NUM> and <NUM>, in which the total content of wax in the homogenized tobacco material is between <NUM> weight percent and <NUM> weight percent on a dry weight basis, and in which the wax is evenly distributed within the homogenized tobacco material. In some aspects of <CIT>, the homogenized tobacco comprises an aerosol-former. In some aspects of <CIT>, the homogenized tobacco comprises a binder. In some aspects of <CIT>, the homogenized tobacco comprises water. In some aspects of <CIT>, the homogenized tobacco comprises non-tobacco flavourants such as menthol. The homogenized tobacco material is suitable for use in a heated aerosol-generating article such as, for example, a "heat-not-burn" type smoking article.

<CIT> discloses a homogenized tobacco material used as an aerosol-forming substrate of an aerosol-generating article e.g. a cigarette or a heat-not-burn type tobacco containing product.

<CIT> discloses devices for generating inhalable aerosol and/or gas, the devices comprising an aerosol generating material and an integrated heating element. In some embodiments of <CIT>, the aerosol generating material may be prepared by drying a slurry comprising <NUM>-<NUM>% tobacco material by weight (e.g. <NUM>% tobacco extract by weight). In some embodiments of <CIT>, the aerosol generating material may be prepared by drying a slurry comprising <NUM>-<NUM>% binder by weight. In some embodiments of <CIT>, the aerosol generating material may be prepared by drying a slurry comprising <NUM>-<NUM>% water by weight. In some embodiments of <CIT>, the aerosol generating material may be prepared by drying a slurry comprising <NUM>-<NUM>% aerosol generating agent by weight (e.g. glycerol).

A first aspect of the invention provides an aerosol generating assembly comprising an aerosol generating substrate and a heater which is configured to heat but not burn the aerosol generating substrate, wherein the aerosol generating substrate comprises an aerosol generating material, the aerosol generating material comprising an amorphous solid, the amorphous solid comprising:.

In some embodiments, the amorphous solid comprises <NUM>-<NUM> wt% of a flavour (dry weight basis).

In some embodiments, the amorphous solid comprising:.

wherein these weights are calculated on a dry weight basis.

In some embodiments, the amorphous solid is a hydrogel and comprises less than about <NUM> wt% of water calculated on a wet weight basis.

In some embodiments, the gelling agent comprises a hydrocolloid. In some cases, the hydrocolloid comprises one or more compounds selected from the group comprising alginates, cellulose derivatives, gums, silica or silicones compounds, clays and combinations thereof. In some cases, the gelling agent comprises alginate and/or pectin, and may be combined with a setting agent (such as a calcium source) during formation of the amorphous solid. In some cases, the amorphous solid may comprise a calcium-crosslinked alginate and/or a calcium-crosslinked pectin.

In some embodiments, the amorphous solid additionally comprises an active substance. In some embodiments, the active substance comprises a tobacco material and/or nicotine. In some embodiments, the amorphous solid comprises powdered tobacco and/or nicotine and/or a tobacco extract.

In some embodiments, the flavour comprises menthol.

In some embodiments, the amorphous solid is formed as a sheet. In some cases, the sheet may be incorporated into the assembly in sheet form. In other cases, the sheet may be shredded and then incorporated into the assembly, suitably mixed into an aerosolisable material such as cut rag tobacco. The sheet may have a mass per unit area of <NUM>-<NUM>/m<NUM>, suitably about <NUM>/m<NUM>.

In some cases, the aerosol generating assembly may be a heat-not-burn device.

In some cases, the aerosol generating assembly may be an electronic tobacco hybrid device.

A second aspect of the invention provides an aerosol generating article for use in an aerosol generating assembly, the article comprising an aerosol generating substrate, the substrate comprising an aerosol generating material, the aerosol generating material comprising an amorphous solid, the amorphous solid comprising:.

In some embodiments, the amorphous solid comprises:.

A third aspect of the invention provides a method of making the assembly according to the first aspect. This method comprises (a) forming a slurry comprising components of the amorphous solid or precursors thereof, (b) forming a layer of the slurry, and (c) setting the slurry to form a gel, (d) drying to form an amorphous solid, and (e) incorporating the resulting amorphous solid into the assembly.

The step (c) of setting the gel may comprise the addition of a setting agent to the slurry.

A further aspect of the invention provides a method of making the assembly according to the first aspect, the assembly comprising the aerosol generating material, the aerosol generating material comprising the amorphous solid, the method comprising:.

In some embodiments, the slurry comprises:.

In some embodiments, the slurry comprises <NUM>-<NUM> wt% menthol. In some embodiments, the slurry comprises <NUM>-<NUM> wt% menthol.

To the extent that they are combinable, features described herein in relation to the one aspect of the invention are explicitly disclosed in combination with each and every other aspect.

Further features and advantages of the invention will become apparent from the following description, given by way of example only, and with reference to the accompanying figures.

As noted above, the invention provides an aerosol generating assembly comprising an aerosol generating substrate and a heater which is configured to heat but not burn the aerosol generating substrate, wherein the substrate comprises an aerosol generating material, where the aerosol generating material comprises an amorphous solid, the amorphous solid comprising:.

The amorphous solid material is formed from a dried gel. The inventors have found that using these component proportions means as the gel sets, flavour compounds are stabilised within the gel matrix allowing a higher flavour loading to be achieved than in non-gel compositions. The flavouring (e.g. menthol) is stabilised at high concentrations and the products have a good shelf life.

In some cases, the amorphous solid may have a thickness of about <NUM> to about <NUM>. Suitably, the thickness may be in the range of about <NUM>, <NUM> or <NUM> to about <NUM> or <NUM>. The inventors have found that a material having a thickness of <NUM> is particularly suitable. The amorphous solid may comprise more than one layer, and the thickness described herein refers to the aggregate thickness of those layers.

The inventors have established that if the aerosol-forming amorphous solid is too thick, then heating efficiency is compromised. This adversely affects the power consumption in use. Conversely, if the aerosol-forming amorphous solid is too thin, it is difficult to manufacture and handle; a very thin material is harder to cast and may be fragile, compromising aerosol formation in use.

The inventors have established that the amorphous solid thicknesses stipulated herein optimise the material properties in view of these competing considerations.

The thickness stipulated herein is a mean thickness for the material. In some cases, the amorphous solid thickness may vary by no more than <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>% or <NUM>%.

Suitably, the amorphous solid may comprise from about 1wt%, 5wt%, 10wt%, 15wt%, 20wt% or 25wt% to about 60wt%, 50wt%, 45wt%, 40wt% or 35wt% of a gelling agent (all calculated on a dry weight basis). For example, the amorphous solid may comprise <NUM>-50wt%, <NUM>-45wt%, <NUM>-40wt% or <NUM>-35wt% of a gelling agent.

In some embodiments, the gelling agent comprises a hydrocolloid. In some embodiments, the gelling agent comprises 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 gelling agent comprises one or more of alginates, pectins, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethylcellulose, pullulan, xanthan gum guar gum, carrageenan, agarose, acacia gum, fumed silica, PDMS, sodium silicate, kaolin and polyvinyl alcohol. In some cases, the gelling agent comprises alginate and/or pectin, and may be combined with a setting agent (such as a calcium source) during formation of the amorphous solid. In some cases, the amorphous solid may comprise a calcium-crosslinked alginate and/or a calcium-crosslinked pectin.

In some embodiments, the gelling agent comprises alginate, and the alginate is present in the amorphous solid in an amount of from <NUM>-30wt% of the amorphous solid (calculated on a dry weight basis). In some embodiments, alginate is the only gelling agent present in the amorphous solid. In other embodiments, the gelling agent comprises alginate and at least one further gelling agent, such as pectin.

In some embodiments the amorphous solid may include gelling agent comprising carrageenan.

Suitably, the amorphous solid may comprise from about <NUM>. 1wt%, <NUM>. 5wt%, 1wt%, 3wt%, 5wt%, 7wt% or <NUM>% to about 50wt%, 45wt%, 40wt%, 35wt%, 30wt% or 25wt% of an aerosol generating agent (all calculated on a dry weight basis). The aerosol generating agent may act as a plasticiser. For example, the amorphous solid may comprise <NUM>-40wt%, <NUM>-35wt% or <NUM>-25wt% of an aerosol generating agent. In some cases, the aerosol generating agent comprises one or more compound selected from erythritol, propylene glycol, glycerol, triacetin, sorbitol and xylitol. In some cases, the aerosol generating agent comprises, consists essentially of or consists of glycerol. The inventors have established that if the content of the plasticiser is too high, the amorphous solid may absorb water resulting in a material that does not create an appropriate consumption experience in use. The inventors have established that if the plasticiser content is too low, the amorphous solid may be brittle and easily broken. The plasticiser content specified herein provides an amorphous solid flexibility which allows the sheet to be wound onto a bobbin, which is useful in manufacture of aerosol generating articles.

The amorphous solid comprises a flavour. Suitably, the amorphous solid may comprise up to about 80wt%, 70wt%, 60wt%, 55wt%, 50wt% or 45wt% of a flavour. In some cases, the amorphous solid may comprise at least about <NUM>. 1wt%, 1wt%, 10wt%, 20wt%, 30wt%, 35wt% or 40wt% of a flavour (all calculated on a dry weight basis). For example, the amorphous solid may comprise <NUM>-80wt%, <NUM>-80wt%, <NUM>-70wt%, <NUM>-60wt%, <NUM>-55wt% or <NUM>-45wt% of a flavour. In some cases, the flavour comprises, consists essentially of or consists of menthol.

In some cases, the amorphous solid may additionally comprise an emulsifying agent, which emulsified molten flavour during manufacture. For example, the amorphous solid may comprise from about 5wt% to about 15wt% of an emulsifying agent (calculated on a dry weight basis), suitably about 10wt%. The emulsifying agent may comprise acacia gum.

In some embodiments, the amorphous solid is a hydrogel and comprises less than about <NUM> wt% of water calculated on a wet weight basis. In some cases, the hydrogel may comprise less than about 15wt%, <NUM> wt% or <NUM> wt% of water calculated on a wet weight basis. In some cases, the hydrogel may comprise at least about 1wt%, 2wt% or at least about 5wt% of water (WWB).

In some embodiments, the amorphous solid additionally comprises an active substance. For example, in some cases, the amorphous solid additionally comprises a tobacco material and/or nicotine. In some cases, the amorphous solid may comprise <NUM>-60wt% (calculated on a dry weight basis) of a tobacco material and/or nicotine. In some cases, the amorphous solid may comprise from about 1wt%, 5wt%, 10wt%, 15wt%, 20wt% or 25wt% to about 70wt%, 60wt%, 50wt%, 45wt%, 40wt%, 35wt%, or 30wt% (calculated on a dry weight basis) of an active substance. In some cases, the amorphous solid may comprise from about 1wt%, 5wt%, 10wt%, 15wt%, 20wt% or 25wt% to about 70wt%, 60wt%, 50wt%, 45wt%, 40wt%, 35wt%, or 30wt% (calculated on a dry weight basis) of a tobacco material. For example, the amorphous solid may comprise <NUM>-50wt%, <NUM>-40wt% or <NUM>-35wt% of a tobacco material. In some cases, the amorphous solid may comprise from about 1wt%, 2wt%, 3wt% or 4wt% to about 20wt%, 18wt%, 15wt% or 12wt% (calculated on a dry weight basis) of nicotine. For example, the amorphous solid may comprise <NUM>-20wt%, <NUM>-18wt% or <NUM>-12wt% of nicotine.

In some cases, the amorphous solid comprises an active substance such as tobacco extract. In some cases, the amorphous solid may comprise <NUM>-60wt% (calculated on a dry weight basis) of tobacco extract. In some cases, the amorphous solid may comprise from about 5wt%, 10wt%, 15wt%, 20wt% or 25wt% to about 60wt%, 50wt%, 45wt%, 40wt%, 35wt%, or 30wt% (calculated on a dry weight basis) tobacco extract. For example, the amorphous solid may comprise <NUM>-50wt%, <NUM>-40wt% or <NUM>-35wt% of tobacco extract. The tobacco extract may contain nicotine at a concentration such that the amorphous solid comprises 1wt% <NUM>. 5wt%, 2wt% or <NUM>. 5wt% to about 6wt%, 5wt%, <NUM>. 5wt% or 4wt% (calculated on a dry weight basis) of nicotine. In some cases, there may be no nicotine in the amorphous solid other than that which results from the tobacco extract.

In some embodiments the amorphous solid comprises no tobacco material but does comprise nicotine. In some such cases, the amorphous solid may comprise from about 1wt%, 2wt%, 3wt% or 4wt% to about 20wt%, 18wt%, 15wt% or 12wt% (calculated on a dry weight basis) of nicotine. For example, the amorphous solid may comprise <NUM>-20wt%, <NUM>-18wt% or <NUM>-12wt% of nicotine.

In some cases, the total content of active substance and/or flavour may be at least about <NUM>. 1wt%, 1wt%, 5wt%, 10wt%, 20wt%, 25wt% or 30wt%. In some cases, the total content of active substance and/or flavour may be less than about 90wt%, 80wt%, 70wt%, 60wt%, 50wt% or 40wt% (all calculated on a dry weight basis).

In some cases, the total content of tobacco material, nicotine and flavour may be at least about <NUM>. 1wt%, 1wt%, 5wt%, 10wt%, 20wt%, 25wt% or 30wt%. In some cases, the total content of active substance and/or flavour may be less than about 90wt%, 80wt%, 70wt%, 60wt%, 50wt% or 40wt% (all calculated on a dry weight basis).

The amorphous solid may be made from a gel, and this gel may additionally comprise a solvent, included at <NUM>-50wt%. However, the inventors have established that the inclusion of a solvent in which the flavour is soluble may reduce the gel stability and the flavour may crystallise out of the gel. As such, in some cases, the gel does not include a solvent in which the flavour is soluble.

In some embodiments, the amorphous solid comprises less than 60wt% of a filler, such as from 1wt% to 60wt%, or 5wt% to 50wt%, or 5wt% to 30wt%, or 10wt% to 20wt%.

In other embodiments, the amorphous solid comprises less than 20wt%, suitably less than 10wt% or less than 5wt% of a filler. In some cases, the amorphous solid comprises less than 1wt% of a filler, and in some cases, comprises no filler.

The filler, if present, 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 comprise one or more organic filler materials such as wood pulp, cellulose and cellulose derivatives. In particular cases, the amorphous solid comprises no calcium carbonate such as chalk.

In particular embodiments which include filler, the filler is fibrous. For example, the filler may be a fibrous organic filler material such as wood pulp, hemp fibre, cellulose or cellulose derivatives. Without wishing to be bound by theory, it is believed that including fibrous filler in an amorphous solid may increase the tensile strength of the material. This may be particularly advantageous in examples wherein the amorphous solid is provided as a sheet, such as when an amorphous solid sheet circumscribes a rod of aerosolisable material.

In some embodiments, the amorphous solid does not comprise tobacco fibres. In particular embodiments, the amorphous solid does not comprise fibrous material.

In some embodiments, the aerosol generating material does not comprise tobacco fibres. In particular embodiments, the aerosol generating material does not comprise fibrous material.

In some embodiments, the aerosol generating substrate does not comprise tobacco fibres. In particular embodiments, the aerosol generating substrate does not comprise fibrous material.

In some embodiments, the aerosol generating article does not comprise tobacco fibres. In particular embodiments, the aerosol generating article does not comprise fibrous material.

In some examples, the amorphous solid in sheet form may have a tensile strength of from around <NUM> N/m to around <NUM> N/m. In some examples, such as where the amorphous solid does not comprise a filler, the amorphous solid may have a tensile strength of from <NUM> N/m to <NUM> N/m, or <NUM> N/m to <NUM> N/m, or about <NUM> N/m. Such tensile strengths may be particularly suitable for embodiments wherein the aerosol generating material is formed as a sheet and then shredded and incorporated into an aerosol generating article. In some examples, such as where the amorphous solid comprises a filler, the amorphous solid may have a tensile strength of from <NUM> N/m to <NUM> N/m, or from <NUM> N/m to <NUM> N/m, or around <NUM> N/m. Such tensile strengths may be particularly suitable for embodiments wherein the aerosol generating material is included in an aerosol generating article/assembly as a rolled sheet, suitably in the form of a tube.

In some cases, the amorphous solid may consist essentially of, or consist of a gelling agent, water, an aerosol generating agent, a flavour, and optionally an active substance.

In some cases, the amorphous solid may consist essentially of, or consist of a gelling agent, water, an aerosol generating agent, a flavour, and optionally a tobacco material and/or a nicotine source.

In some cases, the aerosol-forming amorphous solid layer has a thickness of about <NUM> to about <NUM>, suitably about <NUM> to about <NUM> or <NUM> to about <NUM>. Suitably, the thickness may be in the range of from about <NUM> or <NUM> to about <NUM>, <NUM> or <NUM>. The inventors have found that a material having a thickness of <NUM> is particularly suitable.

The inventors have established that if the aerosol-forming amorphous solid is too thick, then heating efficiency is compromised. This adversely affects the power consumption in use. Conversely, if the aerosol-forming amorphous solid is too thin, it is difficult to manufacture and handle; a very thin material is harder to cast and may be fragile, compromising aerosol formation in use. The inventors have established that the amorphous solid thicknesses stipulated herein optimise the material properties in view of these competing considerations.

The thickness values stipulated herein are mean values for the thickness in question. In some cases, the thickness may vary by no more than <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>% or <NUM>%.

In some embodiments, the amorphous solid is formed as a sheet. In some cases, the amorphous solid sheet may be incorporated into the assembly or article in sheet form. The amorphous solid sheet may be incorporated as a planar sheet, as a gathered or bunched sheet, as a crimped sheet, or as a rolled sheet (i.e. in the form of a tube). In some such cases, the amorphous solid of these embodiments may be included in an aerosol generating article/assembly as a sheet, such as a sheet circumscribing a rod of aerosolisable material (e.g. tobacco). For example, the amorphous solid sheet may be formed on a wrapping paper which circumscribes an aerosolisable material such as tobacco. In other cases, the sheet may be shredded and then incorporated into the assembly, suitably mixed into an aerosolisable material such as cut rag tobacco.

The aerosol generating material comprising the amorphous solid has an area density from <NUM>/m<NUM> to <NUM>/m<NUM>. In some cases, the sheet may have a mass per unit area of <NUM>-<NUM>/m<NUM>, or from about <NUM> to <NUM>/m<NUM>, or particularly from about <NUM> to <NUM>/m<NUM>, or suitably about <NUM>/m<NUM> (so that it has a similar density to cut rag tobacco and a mixture of these substances will not readily separate). Such area densities may be particularly suitable where the aerosol-generating material is included in an aerosol generating article/assembly in sheet form, or as a shredded sheet (described further hereinbelow). In some cases, the sheet may have a mass per unit area of <NUM> to <NUM>/m<NUM> or <NUM> to <NUM>/m<NUM> and may be used to wrap an aerosolisable material such as tobacco.

The aerosol generating substrate may comprise a carrier on which the amorphous solid is provided. The carrier functions as a support on which the amorphous solid layer forms, easing manufacture. The carrier may provide tensile strength to the amorphous solid layer, easing handling.

In some cases, the carrier may be formed from materials selected from metal foil, paper, carbon paper, greaseproof paper, ceramic, carbon allotropes such as graphite and graphene, plastic, cardboard, wood or combinations thereof. In some cases, the carrier may comprise or consist of a tobacco material, such as a sheet of reconstituted tobacco. In some cases, the carrier may be formed from materials selected from metal foil, paper, cardboard, wood or combinations thereof. In some cases, the carrier itself be a laminate structure comprising layers of materials selected from the preceding lists. In some cases, the carrier may also function as a flavour carrier. For example, the carrier may be impregnated with a flavourant or with tobacco extract.

In some cases, the carrier may be magnetic. This functionality may be used to fasten the carrier to the assembly in use, or may be used to generate particular amorphous solid shapes. In some cases, the aerosol generating material may comprise one or more magnets which can be used to fasten the material to an induction heater in use.

In some cases, the carrier may be substantially or wholly impermeable to gas and/or aerosol. This prevents aerosol or gas passage through the carrier layer, thereby controlling the flow and ensuring it is delivered to the user. This can also be used to prevent condensation or other deposition of the gas/aerosol in use on, for example, the surface of a heater provided in an aerosol generating assembly. Thus, consumption efficiency and hygiene can be improved in some cases.

In some cases, the surface of the carrier that abuts the amorphous solid may be porous. For example, in one case, the carrier comprises paper. The inventors have found that a porous carrier such as paper is particularly suitable for the present invention; the porous (e.g. paper) layer abuts the amorphous solid layer and forms a strong bond. The amorphous solid is formed by drying a gel and, without being limited by theory, it is thought that the slurry from which the gel is formed partially impregnates the porous carrier (e.g. paper) so that when the gel sets and forms cross-links, the carrier is partially bound into the gel. This provides a strong binding between the gel and the carrier (and between the dried gel and the carrier).

Additionally, surface roughness may contribute to the strength of bond between the amorphous material and the carrier. The inventors have found that the paper roughness (for the surface abutting the carrier) may suitably be in the range of <NUM>-<NUM> Bekk seconds, suitably <NUM>-<NUM> Bekk seconds, suitably <NUM> Bekk seconds (measured over an air pressure interval of <NUM>-<NUM> kPa). (A Bekk smoothness tester is an instrument used to determine the smoothness of a paper surface, in which air at a specified pressure is leaked between a smooth glass surface and a paper sample, and the time (in seconds) for a fixed volume of air to seep between these surfaces is the "Bekk smoothness".

Conversely, the surface of the carrier facing away from the amorphous solid may be arranged in contact with the heater, and a smoother surface may provide more efficient heat transfer. Thus, in some cases, the carrier is disposed so as to have a rougher side abutting the amorphous material and a smoother side facing away from the amorphous material.

In one particular case, the carrier may be a paper-backed foil; the paper layer abuts the amorphous solid layer and the properties discussed in the previous paragraphs are afforded by this abutment. The foil backing is substantially impermeable, providing control of the aerosol flow path. A metal foil backing may also serve to conduct heat to the amorphous solid.

In another case, the foil layer of the paper-backed foil abuts the amorphous solid. The foil is substantially impermeable, thereby preventing water provided in the amorphous solid to be absorbed into the paper which could weaken its structural integrity.

In some cases, the carrier is formed from or comprises metal foil, such as aluminium foil. A metallic carrier may allow for better conduction of thermal energy to the amorphous solid. Additionally, or alternatively, a metal foil may function as a susceptor in an induction heating system. In particular embodiments, the carrier comprises a metal foil layer and a support layer, such as cardboard. In these embodiments, the metal foil layer may have a thickness of less than <NUM>, such as from about <NUM> to about <NUM>, suitably about <NUM>.

In some cases, the carrier may have a thickness of between about <NUM> and about <NUM>, suitably from about <NUM>, <NUM>, <NUM> or <NUM> to about <NUM>, <NUM>, or <NUM>.

The aerosol generating assembly comprises a heater configured to heat but not burn the aerosol generating substrate. The heater may be, in some cases, a thin film, electrically resistive heater. In other cases, the heater may comprise an induction heater or the like. In yet further cases, the heater may be a combustible heat source or a chemical heat source which undergoes an exothermic reaction to product heat in use.

In some cases, the heater may heat but not burn the aerosolisable material(s) to between <NUM> and <NUM> in use. In some cases, the heater may heat but not burn the aerosolisable material(s) to between <NUM> and <NUM> in use. In some cases in use, substantially all of the amorphous solid is less than about <NUM>, <NUM>, <NUM> or <NUM> from the heater. In some cases, the solid is disposed between about <NUM> and <NUM> from the heater, suitably between about <NUM> and <NUM>. These minimum distances may, in some cases, reflect the thickness of a carrier that supports the amorphous solid. In some cases, a surface of the amorphous solid may directly abut the heater.

In some cases, the heater may be embedded in the aerosol generating substrate. In some such cases, the heater may be an electrically resistive heater (with exposed contacts for connection to an electrical circuit). In other such cases, the heater may be a susceptor embedded in the aerosol generating substrate, which is heated by induction.

The aerosol generating assembly may additionally comprise a cooling element and/or a filter. The cooling element, if present, may act or function to cool gaseous or aerosol components. In some cases, it may act to cool gaseous components such that they condense to form an aerosol. It may also act to space the very hot parts of the apparatus from the user. The filter, if present, may comprise any suitable filter known in the art such as a cellulose acetate plug.

In some cases, the aerosol generating assembly may be a heat-not-burn device. That is, it may contain a solid tobacco-containing material (and no liquid aerosolisable material). In some cases, the amorphous solid may comprise the tobacco material. A heat-not-burn device is disclosed in <CIT>.

In some cases, the aerosol generating assembly may be an electronic tobacco hybrid device. That is, it may contain a solid aerosolisable material and a liquid aerosolisable material. In some cases, the amorphous solid may comprise nicotine. In some cases, the amorphous solid may comprise a tobacco material. In some cases, the amorphous solid may comprise a tobacco material and a separate nicotine source. The separate aerosolisable materials may be heated by separate heaters, the same heater or, in one case, a downstream aerosolisable material may be heated by a hot aerosol which is generated from the upstream aerosolisable material. An electronic tobacco hybrid device is disclosed in <CIT>.

The invention also provides an aerosol generating article for use in an aerosol generating assembly, the article comprising an aerosol generating substrate, the aerosol generating substrate comprising an aerosol generating material, wherein the aerosol generating material comprises an amorphous solid, the amorphous solid comprising:.

In some embodiments, the amorphous solid comprise:
solid comprising:.

The article may alternatively be referred to herein as a cartridge. The article may be adapted for use in a THP, an electronic tobacco hybrid device or another aerosol generating device. In some cases, the article may additionally comprise a filter and/or cooling element, as described previously. In some cases, the aerosol generating article may be circumscribed by a wrapping material such as paper.

The aerosol generating article may additionally comprise ventilation apertures. These may be provided in the sidewall of the article. In some cases, the ventilation apertures may be provided in the filter and/or cooling element. These apertures may allow cool air to be drawn into the article during use, which can mix with the heated volatilised components thereby cooling the aerosol.

The ventilation enhances the generation of visible heated volatilised components from the article when it is heated in use. The heated volatilised components are made visible by the process of cooling the heated volatilised components such that supersaturation of the heated volatilised components occurs. The heated volatilised components then undergo droplet formation, otherwise known as nucleation, and eventually the size of the aerosol particles of the heated volatilised components increases by further condensation of the heated volatilised components and by coagulation of newly formed droplets from the heated volatilised components.

In some cases, the ratio of the cool air to the sum of the heated volatilised components and the cool air, known as the ventilation ratio, is at least <NUM>%. A ventilation ratio of <NUM>% enables the heated volatilised components to be made visible by the method described above. The visibility of the heated volatilised components enables the user to identify that the volatilised components have been generated and adds to the sensory experience of the smoking experience.

In another example, the ventilation ratio is between <NUM>% and <NUM>% to provide additional cooling to the heated volatilised components. In some cases, the ventilation ratio may be at least <NUM>% or <NUM>%.

Referring to <FIG>, there are shown a partially cut-away section view and a perspective view of an example of an aerosol generating article <NUM>. The article <NUM> is adapted for use with a device having a power source and a heater. The article <NUM> of this embodiment is particularly suitable for use with the device <NUM> shown in <FIG>, described below. In use, the article <NUM> may be removably inserted into the device shown in <FIG> at an insertion point <NUM> of the device <NUM>.

The article <NUM> of one example is in the form of a substantially cylindrical rod that includes a body of aerosol generating material <NUM> and a filter assembly <NUM> in the form of a rod. The aerosol generating material comprises the amorphous solid material described herein. In some embodiments, it may be included in sheet form. In some embodiments it may be included in the form of a shredded sheet. In some embodiments, the aerosol generating material described herein may be incorporated in sheet form and in shredded form.

The filter assembly <NUM> includes three segments, a cooling segment <NUM>, a filter segment <NUM> and a mouth end segment <NUM>. The article <NUM> has a first end <NUM>, also known as a mouth end or a proximal end and a second end <NUM>, also known as a distal end. The body of aerosol generating material <NUM> is located towards the distal end <NUM> of the article <NUM>. In one example, the cooling segment <NUM> is located adjacent the body of aerosol generating material <NUM> between the body of aerosol generating material <NUM> and the filter segment <NUM>, such that the cooling segment <NUM> is in an abutting relationship with the aerosol generating material <NUM> and the filter segment <NUM>. In other examples, there may be a separation between the body of aerosol generating material <NUM> and the cooling segment <NUM> and between the body of aerosol generating material <NUM> and the filter segment <NUM>. The filter segment <NUM> is located in between the cooling segment <NUM> and the mouth end segment <NUM>. The mouth end segment <NUM> is located towards the proximal end <NUM> of the article <NUM>, adjacent the filter segment <NUM>. In one example, the filter segment <NUM> is in an abutting relationship with the mouth end segment <NUM>. In one embodiment, the total length of the filter assembly <NUM> is between <NUM> and <NUM>, more preferably, the total length of the filter assembly <NUM> is <NUM>.

In one example, the rod of aerosol generating material <NUM> is between <NUM> and <NUM> in length, suitably between <NUM> and <NUM> in length, suitably <NUM> in length.

In one example, the total length of the article <NUM> is between <NUM> and <NUM>, suitably between <NUM> and <NUM>, suitably <NUM>.

An axial end of the body of aerosol generating material <NUM> is visible at the distal end <NUM> of the article <NUM>. However, in other embodiments, the distal end <NUM> of the article <NUM> may comprise an end member (not shown) covering the axial end of the body of aerosol generating material <NUM>.

The body of aerosol generating material <NUM> is joined to the filter assembly <NUM> by annular tipping paper (not shown), which is located substantially around the circumference of the filter assembly <NUM> to surround the filter assembly <NUM> and extends partially along the length of the body of aerosol generating material <NUM>. In one example, the tipping paper is made of 58GSM standard tipping base paper. In one example the tipping paper has a length of between <NUM> and <NUM>, suitably of <NUM>.

In one example, the cooling segment <NUM> is an annular tube and is located around and defines an air gap within the cooling segment. The air gap provides a chamber for heated volatilised components generated from the body of aerosol generating material <NUM> to flow. The cooling segment <NUM> is hollow to provide a chamber for aerosol accumulation yet rigid enough to withstand axial compressive forces and bending moments that might arise during manufacture and whilst the article <NUM> is in use during insertion into the device <NUM>. In one example, the thickness of the wall of the cooling segment <NUM> is approximately <NUM>.

The cooling segment <NUM> provides a physical displacement between the aerosol generating material <NUM> and the filter segment <NUM>. The physical displacement provided by the cooling segment <NUM> will provide a thermal gradient across the length of the cooling segment <NUM>. In one example the cooling segment <NUM> is configured to provide a temperature differential of at least <NUM> degrees Celsius between a heated volatilised component entering a first end of the cooling segment <NUM> and a heated volatilised component exiting a second end of the cooling segment <NUM>. In one example the cooling segment <NUM> is configured to provide a temperature differential of at least <NUM> degrees Celsius between a heated volatilised component entering a first end of the cooling segment <NUM> and a heated volatilised component exiting a second end of the cooling segment <NUM>. This temperature differential across the length of the cooling element <NUM> protects the temperature sensitive filter segment <NUM> from the high temperatures of the aerosol generating material <NUM> when it is heated by the device <NUM>. If the physical displacement was not provided between the filter segment <NUM> and the body of aerosol generating material <NUM> and the heating elements of the device <NUM>, then the temperature sensitive filter segment may <NUM> become damaged in use, so it would not perform its required functions as effectively.

In one example the length of the cooling segment <NUM> is at least <NUM>. In one example, the length of the cooling segment <NUM> is between <NUM> and <NUM>, more particularly <NUM> to <NUM>, more particularly <NUM> to <NUM>, suitably <NUM>.

The cooling segment <NUM> is made of paper, which means that it is comprised of a material that does not generate compounds of concern, for example, toxic compounds when in use adj acent to the heater of the device <NUM>. In one example, the cooling segment <NUM> is manufactured from a spirally wound paper tube which provides a hollow internal chamber yet maintains mechanical rigidity. Spirally wound paper tubes are able to meet the tight dimensional accuracy requirements of high-speed manufacturing processes with respect to tube length, outer diameter, roundness and straightness.

In another example, the cooling segment <NUM> is a recess created from stiff plug wrap or tipping paper. The stiff plug wrap or tipping paper is manufactured to have a rigidity that is sufficient to withstand the axial compressive forces and bending moments that might arise during manufacture and whilst the article <NUM> is in use during insertion into the device <NUM>.

The filter segment <NUM> may be formed of any filter material sufficient to remove one or more volatilised compounds from heated volatilised components from the aerosol generating material. In one example the filter segment <NUM> is made of a monoacetate material, such as cellulose acetate. The filter segment <NUM> provides cooling and irritation-reduction from the heated volatilised components without depleting the quantity of the heated volatilised components to an unsatisfactory level for a user.

In some embodiments, a capsule (not illustrated) may be provided in filter segment <NUM>. It may be disposed substantially centrally in the filter segment <NUM>, both across the filter segment <NUM> diameter and along the filter segment <NUM> length. In other cases, it may be offset in one or more dimension. The capsule may in some cases, where present, contain a volatile component such as a flavourant or aerosol generating agent.

The density of the cellulose acetate tow material of the filter segment <NUM> controls the pressure drop across the filter segment <NUM>, which in turn controls the draw resistance of the article <NUM>. Therefore the selection of the material of the filter segment <NUM> is important in controlling the resistance to draw of the article <NUM>. In addition, the filter segment performs a filtration function in the article <NUM>.

In one example, the filter segment <NUM> is made of a 8Y15 grade of filter tow material, which provides a filtration effect on the heated volatilised material, whilst also reducing the size of condensed aerosol droplets which result from the heated volatilised material.

The presence of the filter segment <NUM> provides an insulating effect by providing further cooling to the heated volatilised components that exit the cooling segment <NUM>. This further cooling effect reduces the contact temperature of the user's lips on the surface of the filter segment <NUM>.

In one example, the filter segment <NUM> is between <NUM> to <NUM> in length, suitably <NUM>.

The mouth end segment <NUM> is an annular tube and is located around and defines an air gap within the mouth end segment <NUM>. The air gap provides a chamber for heated volatilised components that flow from the filter segment <NUM>. The mouth end segment <NUM> is hollow to provide a chamber for aerosol accumulation yet rigid enough to withstand axial compressive forces and bending moments that might arise during manufacture and whilst the article is in use during insertion into the device <NUM>. In one example, the thickness of the wall of the mouth end segment <NUM> is approximately <NUM>. In one example, the length of the mouth end segment <NUM> is between <NUM> to <NUM>, suitably <NUM>.

The mouth end segment <NUM> may be manufactured from a spirally wound paper tube which provides a hollow internal chamber yet maintains critical mechanical rigidity. Spirally wound paper tubes are able to meet the tight dimensional accuracy requirements of high-speed manufacturing processes with respect to tube length, outer diameter, roundness and straightness.

The mouth end segment <NUM> provides the function of preventing any liquid condensate that accumulates at the exit of the filter segment <NUM> from coming into direct contact with a user.

It should be appreciated that, in one example, the mouth end segment <NUM> and the cooling segment <NUM> may be formed of a single tube and the filter segment <NUM> is located within that tube separating the mouth end segment <NUM> and the cooling segment <NUM>.

Referring to <FIG>, there are shown a partially cut-away section and perspective views of an example of an article <NUM>. The reference signs shown in <FIG> are equivalent to the reference signs shown in <FIG>, but with an increment of <NUM>.

In the example of the article <NUM> shown in <FIG>, a ventilation region <NUM> is provided in the article <NUM> to enable air to flow into the interior of the article <NUM> from the exterior of the article <NUM>. In one example the ventilation region <NUM> takes the form of one or more ventilation holes <NUM> formed through the outer layer of the article <NUM>. The ventilation holes may be located in the cooling segment <NUM> to aid with the cooling of the article <NUM>. In one example, the ventilation region <NUM> comprises one or more rows of holes, and preferably, each row of holes is arranged circumferentially around the article <NUM> in a cross-section that is substantially perpendicular to a longitudinal axis of the article <NUM>.

In one example, there are between one to four rows of ventilation holes to provide ventilation for the article <NUM>. Each row of ventilation holes may have between <NUM> to <NUM> ventilation holes <NUM>. The ventilation holes <NUM> may, for example, be between <NUM> to <NUM> in diameter. In one example, an axial separation between rows of ventilation holes <NUM> is between <NUM> and <NUM>, suitably <NUM>.

In one example, the ventilation holes <NUM> are of uniform size. In another example, the ventilation holes <NUM> vary in size. The ventilation holes can be made using any suitable technique, for example, one or more of the following techniques: laser technology, mechanical perforation of the cooling segment <NUM> or pre-perforation of the cooling segment <NUM> before it is formed into the article <NUM>. The ventilation holes <NUM> are positioned so as to provide effective cooling to the article <NUM>.

In one example, the rows of ventilation holes <NUM> are located at least <NUM> from the proximal end <NUM> of the article, suitably between <NUM> and <NUM> from the proximal end <NUM> of the article <NUM>. The location of the ventilation holes <NUM> is positioned such that user does not block the ventilation holes <NUM> when the article <NUM> is in use.

Providing the rows of ventilation holes between <NUM> and <NUM> from the proximal end <NUM> of the article <NUM> enables the ventilation holes <NUM> to be located outside of the device <NUM>, when the article <NUM> is fully inserted in the device <NUM>, as can be seen in <FIG> and <FIG>. By locating the ventilation holes outside of the device, non-heated air is able to enter the article <NUM> through the ventilation holes from outside the device <NUM> to aid with the cooling of the article <NUM>.

The length of the cooling segment <NUM> is such that the cooling segment <NUM> will be partially inserted into the device <NUM>, when the article <NUM> is fully inserted into the device <NUM>. The length of the cooling segment <NUM> provides a first function of providing a physical gap between the heater arrangement of the device <NUM> and the heat sensitive filter arrangement <NUM>, and a second function of enabling the ventilation holes <NUM> to be located in the cooling segment, whilst also being located outside of the device <NUM>, when the article <NUM> is fully inserted into the device <NUM>. As can be seen from <FIG> and <FIG>, the majority of the cooling element <NUM> is located within the device <NUM>. However, there is a portion of the cooling element <NUM> that extends out of the device <NUM>. It is in this portion of the cooling element <NUM> that extends out of the device <NUM> in which the ventilation holes <NUM> are located.

Referring now to <FIG> in more detail, there is shown an example of a device <NUM> arranged to heat aerosol generating material to volatilise at least one component of said aerosol generating material, typically to form an aerosol which can be inhaled. The device <NUM> is a heating device which releases compounds by heating, but not burning, the aerosol generating material.

A first end <NUM> is sometimes referred to herein as the mouth or proximal end <NUM> of the device <NUM> and a second end <NUM> is sometimes referred to herein as the distal end <NUM> of the device <NUM>. The device <NUM> has an on/off button <NUM> to allow the device <NUM> as a whole to be switched on and off as desired by a user.

The device <NUM> comprises a housing <NUM> for locating and protecting various internal components of the device <NUM>. In the example shown, the housing <NUM> comprises a uni-body sleeve <NUM> that encompasses the perimeter of the device <NUM>, capped with a top panel <NUM> which defines generally the 'top' of the device <NUM> and a bottom panel <NUM> which defines generally the 'bottom' of the device <NUM>. In another example the housing comprises a front panel, a rear panel and a pair of opposite side panels in addition to the top panel <NUM> and the bottom panel <NUM>.

The top panel <NUM> and/or the bottom panel <NUM> may be removably fixed to the uni-body sleeve <NUM>, to permit easy access to the interior of the device <NUM>, or may be "permanently" fixed to the uni-body sleeve <NUM>, for example to deter a user from accessing the interior of the device <NUM>. In an example, the panels <NUM> and <NUM> are made of a plastics material, including for example glass-filled nylon formed by injection moulding, and the uni-body sleeve <NUM> is made of aluminium, though other materials and other manufacturing processes may be used.

The top panel <NUM> of the device <NUM> has an opening <NUM> at the mouth end <NUM> of the device <NUM> through which, in use, the article <NUM>, <NUM> including the aerosol generating material may be inserted into the device <NUM> and removed from the device <NUM> by a user.

The housing <NUM> has located or fixed therein a heater arrangement <NUM>, control circuitry <NUM> and a power source <NUM>. In this example, the heater arrangement <NUM>, the control circuitry <NUM> and the power source <NUM> are laterally adjacent (that is, adjacent when viewed from an end), with the control circuitry <NUM> being located generally between the heater arrangement <NUM> and the power source <NUM>, though other locations are possible.

The control circuitry <NUM> may include a controller, such as a microprocessor arrangement, configured and arranged to control the heating of the aerosol generating material in the article <NUM>, <NUM> as discussed further below.

The power source <NUM> may be for example a battery, which may be a rechargeable battery or a non-rechargeable battery. Examples of suitable batteries include for example a lithium-ion battery, a nickel battery (such as a nickel-cadmium battery), an alkaline battery and/ or the like. The battery <NUM> is electrically coupled to the heater arrangement <NUM> to supply electrical power when required and under control of the control circuitry <NUM> to heat the aerosol generating material in the article (as discussed, to volatilise the aerosol generating material without causing the aerosol generating material to burn).

An advantage of locating the power source <NUM> laterally adjacent to the heater arrangement <NUM> is that a physically large power source <NUM> may be used without causing the device <NUM> as a whole to be unduly lengthy. As will be understood, in general a physically large power source <NUM> has a higher capacity (that is, the total electrical energy that can be supplied, often measured in Amp-hours or the like) and thus the battery life for the device <NUM> can be longer.

In one example, the heater arrangement <NUM> is generally in the form of a hollow cylindrical tube, having a hollow interior heating chamber <NUM> into which the article <NUM>, <NUM> comprising the aerosol generating material is inserted for heating in use. Different arrangements for the heater arrangement <NUM> are possible. For example, the heater arrangement <NUM> may comprise a single heating element or may be formed of plural heating elements aligned along the longitudinal axis of the heater arrangement <NUM>. The or each heating element may be annular or tubular, or at least part-annular or part-tubular around its circumference. In an example, the or each heating element may be a thin film heater. In another example, the or each heating element may be made of a ceramics material. Examples of suitable ceramics materials include alumina and aluminium nitride and silicon nitride ceramics, which may be laminated and sintered. Other heating arrangements are possible, including for example inductive heating, infrared heater elements, which heat by emitting infrared radiation, or resistive heating elements formed by for example a resistive electrical winding.

In one particular example, the heater arrangement <NUM> is supported by a stainless steel support tube and comprises a polyimide heating element. The heater arrangement <NUM> is dimensioned so that substantially the whole of the body of aerosol generating material <NUM>, <NUM> of the article <NUM>, <NUM> is inserted into the heater arrangement <NUM> when the article <NUM>, <NUM> is inserted into the device <NUM>.

The or each heating element may be arranged so that selected zones of the aerosol generating material can be independently heated, for example in turn (over time, as discussed above) or together (simultaneously) as desired.

The heater arrangement <NUM> in this example is surrounded along at least part of its length by a thermal insulator <NUM>. The insulator <NUM> helps to reduce heat passing from the heater arrangement <NUM> to the exterior of the device <NUM>. This helps to keep down the power requirements for the heater arrangement <NUM> as it reduces heat losses generally. The insulator <NUM> also helps to keep the exterior of the device <NUM> cool during operation of the heater arrangement <NUM>. In one example, the insulator <NUM> may be a double-walled sleeve which provides a low pressure region between the two walls of the sleeve. That is, the insulator <NUM> may be for example a "vacuum" tube, i.e. a tube that has been at least partially evacuated so as to minimise heat transfer by conduction and/or convection. Other arrangements for the insulator <NUM> are possible, including using heat insulating materials, including for example a suitable foam-type material, in addition to or instead of a double-walled sleeve.

The housing <NUM> may further comprises various internal support structures <NUM> for supporting all internal components, as well as the heating arrangement <NUM>.

The device <NUM> further comprises a collar <NUM> which extends around and projects from the opening <NUM> into the interior of the housing <NUM> and a generally tubular chamber <NUM> which is located between the collar <NUM> and one end of the vacuum sleeve <NUM>. The chamber <NUM> further comprises a cooling structure 35f, which in this example, comprises a plurality of cooling fins 35f spaced apart along the outer surface of the chamber <NUM>, and each arranged circumferentially around outer surface of the chamber <NUM>. There is an air gap <NUM> between the hollow chamber <NUM> and the article <NUM>, <NUM> when it is inserted in the device <NUM> over at least part of the length of the hollow chamber <NUM>. The air gap <NUM> is around all of the circumference of the article <NUM>, <NUM> over at least part of the cooling segment <NUM>.

The collar <NUM> comprises a plurality of ridges <NUM> arranged circumferentially around the periphery of the opening <NUM> and which project into the opening <NUM>. The ridges <NUM> take up space within the opening <NUM> such that the open span of the opening <NUM> at the locations of the ridges <NUM> is less than the open span of the opening <NUM> at the locations without the ridges <NUM>. The ridges <NUM> are configured to engage with an article <NUM>, <NUM> inserted into the device to assist in securing it within the device <NUM>. Open spaces (not shown in the Figures) defined by adjacent pairs of ridges <NUM> and the article <NUM>, <NUM> form ventilation paths around the exterior of the article <NUM>, <NUM>. These ventilation paths allow hot vapours that have escaped from the article <NUM>, <NUM> to exit the device <NUM> and allow cooling air to flow into the device <NUM> around the article <NUM>, <NUM> in the air gap <NUM>.

In operation, the article <NUM>, <NUM> is removably inserted into an insertion point <NUM> of the device <NUM>, as shown in <FIG>. Referring particularly to <FIG>, in one example, the body of aerosol generating material <NUM>, <NUM>, which is located towards the distal end <NUM>, <NUM> of the article <NUM>, <NUM>, is entirely received within the heater arrangement <NUM> of the device <NUM>. The proximal end <NUM>, <NUM> of the article <NUM>, <NUM> extends from the device <NUM> and acts as a mouthpiece assembly for a user.

In operation, the heater arrangement <NUM> will heat the article <NUM>, <NUM> to volatilise at least one component of the aerosol generating material from the body of aerosol generating material <NUM>, <NUM>.

The primary flow path for the heated volatilised components from the body of aerosol generating material <NUM>, <NUM> is axially through the article <NUM>, <NUM>, through the chamber inside the cooling segment <NUM>, <NUM>, through the filter segment <NUM>, <NUM>, through the mouth end segment <NUM>, <NUM> to the user. In one example, the temperature of the heated volatilised components that are generated from the body of aerosol generating material is between <NUM> and <NUM>, which may be above the acceptable inhalation temperature for a user. As the heated volatilised component travels through the cooling segment <NUM>, <NUM>, it will cool and some volatilised components will condense on the inner surface of the cooling segment <NUM>, <NUM>.

In the examples of the article <NUM> shown in <FIG>, cool air will be able to enter the cooling segment <NUM> via the ventilation holes <NUM> formed in the cooling segment <NUM>. This cool air will mix with the heated volatilised components to provide additional cooling to the heated volatilised components.

The step (b) of forming a layer of the slurry may comprise spraying, casting or extruding the slurry, for example. In some cases, the layer is formed by electrospraying the slurry. In some cases, the layer is formed by casting the slurry.

In some cases, the steps (b) and/or (c) and/or (d) may, at least partially, occur simultaneously (for example, during electrospraying). In some cases, these steps may occur sequentially.

In some cases, a setting agent (such as a calcium source) may be added to the slurry before or during step (b). This is appropriate in instances where gelation occurs relatively slowly (e.g. with alginate gelling agent), and thus the slurry may be, e.g. cast, after the setting agent is added.

In other cases, the step (c) of setting the slurry as a gel may comprise the addition of a setting agent to the slurry layer. The setting agent may be sprayed onto the gel, for example, or may be preloaded onto the surface on which the slurry is layered.

For example, a setting agent comprising a calcium source (such as calcium chloride or calcium citrate), may be added to a slurry containing alginate and/or pectin to form a calcium-crosslinked alginate/pectin gel. In some cases where gelation occurs rapidly (such as those in which a pectin gelling agent is used), the calcium should be added after casting (because the gel is too viscous to cast).

The total amount of the setting agent, such as a calcium source, may be <NUM>-5wt% (calculated on a dry weight basis). The inventors have found that the addition of too little setting agent may result in a gel which does not stabilise the flavour and results in the flavour dropping out of the gel. The inventors have found that the addition of too much setting agent results in a gel that is very tacky and consequently has poor handleability.

Alginate salts are derivatives of alginic acid and are typically high molecular weight polymers (<NUM>-<NUM> kDa). Alginic acid is a copolymer of β-D-mannuronic (M) and α-L-guluronic acid (G) units (blocks) linked together with (<NUM>,<NUM>)-glycosidic bonds to form a polysaccharide. On addition of calcium cations, the alginate crosslinks to form a gel. The inventors have determined that alginate salts with a high G monomer content more readily form a gel on addition of the calcium source. In some cases therefore, the gel-precursor pay comprise an alginate salt in which at least about <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>% or <NUM>% of the monomer units in the alginate copolymer are α-L-guluronic acid (G) units.

In some cases, the slurry may be warmed prior to and during casting. This can slow gelation, improving handleability and easing the casting process. Further, warming the slurry may melt the flavour components (e.g. menthol) easing handleability.

In some cases, menthol (or other flavours) may be distributed through the slurry in powder form. In some cases, menthol (or other flavours) may be molten in the slurry (where it is warmed). In such cases, an emulsifying agent such as acacia gum may be added to disperse molten menthol in the slurry.

In some cases, the slurry may be cast onto a bandcast sheet. The sheet may be loaded with a releasing agent, such as lecithin, which can aid separation of the bandcast and the amorphous solid.

The slurry in the method of the third aspect of the invention may comprise.

In some cases, the slurry solvent may consist essentially of or consist of water. In some cases, the slurry may comprise from about 50wt%, 60wt%, 70wt%, 80wt% or 90wt% of solvent (WWB).

In some examples, the slurry has a viscosity of from about <NUM> to about <NUM> Pa·s at <NUM>, such as from about <NUM> to about <NUM> Pa·s at <NUM>.

A further aspect of the present invention provides a method of making the assembly according to the first aspect, the assembly comprising the aerosol generating material, the aerosol generating material comprising the amorphous solid, the method comprising:.

Surprisingly, the inventors have identified that the use of molten menthol in a manufacturing process (as opposed to menthol in powder form) may reduce contamination of other machinery in the manufacturing location with menthol. In particular, providing menthol in molten form before combining at least some or all of the other components of the slurry may reduce contamination of other machinery (i.e. menthol is molten before all of the components in the slurry are combined). The use of molten menthol may also allow for improved dispersion of the menthol throughout the resulting amorphous solid, and/or providing an amorphous solid wherein more of the starting menthol present in the slurry is retained in the amorphous solid.

The gelling agent may be any suitable gelling agent. In some embodiments, the gelling agent comprises alginate and/or pectin.

In cases where the solvent consists of water, the dry weight content of the slurry will match the dry weight content of the amorphous solid. Thus, the discussion herein relating to the solid composition is explicitly disclosed in combination with any slurry aspect of the invention.

In some embodiments, the amorphous solid comprises menthol.

Particular embodiments comprising a menthol-containing amorphous solid may be particularly suitable for including in an aerosol generating article/assembly as a shredded sheet. In these embodiments, the amorphous solid may have the following composition (DWB): gelling agent (preferably comprising alginate, more preferably comprising a combination of alginate and pectin) in an amount of from about 20wt% to about 40wt%, or about 25wt% to 35wt%; menthol in an amount of from about 35wt% to about 60wt%, or from about 40wt% to 55wt%; aerosol generating agent (preferably comprising glycerol) in an amount of from about 10wt% to about 30wt%, or from about 15wt% to about 25wt% (DWB).

In one embodiment, the amorphous solid comprises about <NUM>-33wt% of an alginate/pectin gelling agent blend; about <NUM>-48wt% menthol flavourant; and about <NUM>-20wt% glycerol aerosol generating agent (DWB).

As noted above, the amorphous solid of these embodiments may be included in an aerosol generating article/assembly as a shredded sheet. The shredded sheet may be provided in the article/assembly blended with cut tobacco. Alternatively, the amorphous solid may be provided as a non-shredded sheet. Suitably, the shredded or non-shredded sheet has a thickness of from about <NUM> to about <NUM>, preferably from about <NUM> to about <NUM>.

Particular embodiments of the menthol-containing amorphous solid may be particularly suitable for including in an aerosol generating article/assembly as a sheet, such as a sheet circumscribing a rod of aerosolisable material (e.g. tobacco). In these embodiments, the amorphous solid may have the following composition (DWB): gelling agent (preferably comprising alginate, more preferably comprising a combination of alginate and pectin) in an amount of from about 5wt% to about 40wt%, or about 10wt% to 30wt%; menthol in an amount of from about 10wt% to about 50wt%, or from about 15wt% to 40wt%; aerosol generating agent (preferably comprising glycerol) in an amount of from about 5wt% to about 40wt%, or from about 10wt% to about 35wt%; and optionally filler in an amount of up to 60wt% - for example, in an amount of from 5wt% to 20wt%, or from about 40wt% to 60wt% (DWB).

In one of these embodiments, the amorphous solid comprises about 11wt% of an alginate/pectin gelling agent blend, about 56wt% woodpulp filler, about <NUM>% menthol flavourant and about 15wt% glycerol (DWB).

In another of these embodiments, the amorphous solid comprises about 22wt% of an alginate/pectin gelling agent blend, about 12wt% woodpulp filler, about <NUM>% menthol flavourant and about 30wt% glycerol (DWB).

As noted above, the amorphous solid of these embodiments may be included as a sheet. In one embodiment, the sheet is provided on a carrier comprising paper. In one embodiment, the sheet is provided on a carrier comprising metal foil, suitably aluminium metal foil. In this embodiment, the amorphous solid may abut the metal foil.

In one embodiment, the sheet forms part of a laminate material with a layer (preferably comprising paper) attached to a top and bottom surface of the sheet. Suitably, the sheet of amorphous solid has a thickness of from about <NUM> to about <NUM>.

In some embodiments, the amorphous solid comprises a flavourant which does not comprise menthol. In these embodiments, the amorphous solid may have the following composition (DWB): gelling agent (preferably comprising alginate) in an amount of from about <NUM> to about 40wt%, or from about 10wt% to about 35wt%, or from about 20wt% to about 35wt%; flavourant in an amount of from about <NUM>. 1wt% to about 40wt%, of from about 1wt% to about 30wt%, or from about 1wt% to about 20wt%, or from about 5wt% to about 20wt%; aerosol generating agent (preferably comprising glycerol) in an amount of from 15wt% to 75wt%, or from about 30wt% to about 70wt%, or from about 50wt% to about 65wt%; and optionally filler (suitably woodpulp) in an amount of less than about 60wt%, or about 20wt%, or about 10wt%, or about 5wt% (preferably the amorphous solid does not comprise filler) (DWB).

In one of these embodiments, the amorphous solid comprises about 27wt% alginate gelling agent, about 14wt% flavourant and about 57wt% glycerol aerosol generating agent (DWB).

In another of these embodiments, the amorphous solid comprises about 29wt% alginate gelling agent, about 9wt% flavourant and about 60wt% glycerol (DWB).

The amorphous solid of these embodiments may be included in an aerosol generating article/assembly as a shredded sheet, optionally blended with cut tobacco. Alternatively, the amorphous solid of these embodiments may be included in an aerosol generating article/assembly as a sheet, such as a sheet circumscribing a rod of aerosolisable material (e.g. tobacco). Alternatively, the amorphous solid of these embodiments may be included in an aerosol generating article/assembly as a layer portion disposed on a carrier.

In a first example, a slurry having the following composition was formed in a high-shear mixer. Water and glycerol were first mixed, and the alginate and ground menthol powder then added. The alginate was fully hydrated before the calcium citrate was added. The slurry was cast at <NUM> thickness at room temperature and allowed to set as a gel. The gel was then dried in an oven (<NUM> for <NUM>-<NUM> hrs).

In a second example, a slurry having the following composition was formed in a high-shear mixer. Water and glycerol were first mixed, and the pectin and ground menthol powder then added. The slurry was warmed during mixing to <NUM>-<NUM> to melt menthol and reduce the slurry viscosity.

The warmed slurry was cast at <NUM> thickness. An aqueous solution of calcium chloride (<NUM> calcium chloride dissolved in water) was sprayed onto the cast to effect gelation. The gel was then dried in an oven (<NUM> for <NUM>-<NUM> hrs).

In this second example, the calcium source was added after casting due to the speed of gelation of the pectin gelling agent. If calcium were to be added prior to casting, gelation would occur rapidly and the material could not be easily cast.

The slurry may comprise molten menthol in this second example because the pectin gelling agent has groups along the polysaccharide chain that emulsify the menthol in the slurry. In the case of the first example, the alginate gelling agent does not have these emulsifying properties, and so menthol is used in dry powder form.

The aerosol generating material described herein comprises an "amorphous solid", which may alternatively be referred to as a "monolithic solid" (i.e. non-fibrous), or as a "dried gel". The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some cases, the aerosol generating the material comprises from 50wt%, 60wt% or 70wt% of amorphous solid, to about 90wt%, 95wt% or 100wt% of amorphous solid. In some cases, the aerosol generating material consists of amorphous solid.

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.

In some embodiments, the active substance comprises nicotine.

In some embodiments, the active substance comprises caffeine, melatonin or vitamin B12.

As noted herein, the active substance may comprise one or more constituents, derivatives or extracts of cannabis, such as one or more cannabinoids or terpenes.

Cannabinoids are a class of natural or synthetic chemical compounds which act on cannabinoid receptors (i.e., CB1 and CB2) in cells that repress neurotransmitter release in the brain. Cannabinoids may be naturally occurring (phytocannabinoids) from plants such as cannabis, from animals (endocannabinoids), or artificially manufactured (synthetic cannabinoids). Cannabis species express at least <NUM> different phytocannabinoids, and are divided into subclasses, including cannabigerols, cannabichromenes, cannabidiols, tetrahydrocannabinols, cannabinols and cannabinodiols, and other cannabinoids. Cannabinoids found in cannabis include, without limitation: cannabigerol (CBG), cannabichromene (CBC), cannabidiol (CBD), tetrahydrocannabinol (THC), cannabinol (CBN), cannabinodiol (CBDL), cannabicyclol (CBL), cannabivarin (CBV), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), cannabichromevarin (CBCV), cannabigerovarin (CBGV), cannabigerol monomethyl ether (CBGM), cannabinerolic acid, cannabidiolic acid (CBDA), Cannabinol propyl variant (CBNV), cannabitriol (CBO), tetrahydrocannabmolic acid (THCA), and tetrahydrocannabivarinic acid (THCV A).

As noted herein, the active substance may comprise or be derived from one or more botanicals or constituents, derivatives or extracts thereof. As used herein, the term "botanical" includes any material derived from plants including, but not limited to, extracts, leaves, bark, fibres, stems, roots, seeds, flowers, fruits, pollen, husk, shells or the like. Alternatively, the material may comprise an active compound naturally existing in a botanical, obtained synthetically. The material may be in the form of liquid, gas, solid, powder, dust, crushed particles, granules, pellets, shreds, strips, sheets, or the like. 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 arvensis, Mentha c. , Mentha niliaca, Mentha piperita, Mentha piperita citrata c. , Mentha piperita c. , Mentha spicata crispa, Mentha cordifolia, Mentha longifolia, Mentha suaveolens variegata, Mentha pulegium, Mentha spicata c. and Mentha suaveolens.

In some embodiments, the botanical is selected from eucalyptus, star anise, cocoa and hemp.

In some embodiments, the botanical is selected from rooibos and fennel.

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 may be 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.

The flavour may suitably comprise one or more mint-flavours suitably a mint oil from any species of the genus Mentha. The flavour may suitably comprise, consist essentially of or consist of menthol.

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

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.

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 limited to eucalyptol, WS-<NUM>.

As used herein, the term "aerosol generating agent" refers to an agent that promotes the generation of an aerosol. An aerosol generating agent may promote the generation of an aerosol by promoting an initial vaporisation and/or the condensation of a gas to an inhalable solid and/or liquid aerosol.

Suitable aerosol generating agents include, but are not limited to: a polyol such as erythritol, sorbitol, glycerol, and glycols like propylene glycol or triethylene glycol; a non-polyol such as monohydric alcohols, high boiling point hydrocarbons, acids such as lactic acid, glycerol derivatives, esters such as diacetin, triacetin, triethylene glycol diacetate, triethyl citrate or myristates including ethyl myristate and isopropyl myristate and aliphatic carboxylic acid esters such as methyl stearate, dimethyl dodecanedioate and dimethyl tetradecanedioate. The aerosol generating agent may suitably have a composition that does not dissolve menthol. The aerosol generating agent may suitably comprise, consist essentially of or consist of glycerol.

As used herein, the term "tobacco material" refers to any material comprising tobacco or derivatives therefore. 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, tobacco stem, reconstituted tobacco and/or tobacco extract.

The tobacco used to produce tobacco material may be any suitable tobacco, such as single grades or blends, cut rag or whole leaf, including Virginia and/or Burley and/or Oriental. It may also be tobacco particle 'fines' or dust, expanded tobacco, stems, expanded stems, and other processed stem materials, such as cut rolled stems. The tobacco material may be a ground tobacco or a reconstituted tobacco material. The reconstituted tobacco material may comprise tobacco fibres, and may be formed by casting, a Fourdrinier-based paper making-type approach with back addition of tobacco extract, or by extrusion.

All percentages by weight described herein (denoted wt%) are calculated on a dry weight basis, unless explicitly stated otherwise. All weight ratios are also calculated on a dry weight basis. A weight quoted on a dry weight basis refers to the whole of the extract or slurry or material, other than the water, and may include components which by themselves are liquid at room temperature and pressure, such as glycerol. Conversely, a weight percentage quoted on a wet weight basis refers to all components, including water.

Claim 1:
An aerosol generating assembly comprising an aerosol generating substrate and a heater which is configured to heat but not burn the aerosol generating material, wherein the aerosol generating substrate comprises an aerosol generating material, the aerosol generating material comprising an amorphous solid, the amorphous solid comprising:
- <NUM>-<NUM> wt% of a gelling agent;
- <NUM>-<NUM> wt% of an aerosol generating agent; and
- <NUM>-<NUM> wt% of a flavour;
wherein these weights are calculated on a dry weight basis;
wherein the aerosol generating material has an area density of from <NUM> to <NUM>/m<NUM>.