Aerosol generating material

Abstract

An aerosol generating material is described, for use in an article for use with a non-combustible aerosol-provision device. The aerosol generating material comprises tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w).

Description

Technical Field

[0001] The present disclosure relates to an aerosol generating material comprising tobacco and a non-combustible aerosol-provision system comprising the aerosol generating material.Background

[0002] Aerosol generating materials are typically heated, for example by a non-combustible aerosol-provision system, to form an aerosol, which may be inhaled by a consumer.

[0003] Aerosol generating materials may be made from various different sources, including from tobacco material and may include additives to modify the aerosol generated when the aerosol generating material is heated.Summary

[0004] According to a first aspect of the present disclosure, there is provided an aerosol generating material for use in an article for use with a non-combustible aerosol-provision device, the aerosol generating material comprising tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w).

[0005] The inventors have surprisingly discovered that the inclusion of a combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) reduces the TSNA content of the aerosol generated upon heating of the aerosol generating material in comparison to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent. This synergistic effect of TSNA reduction was surprisingly found not to occur in aerosol generating materials comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of less than 650 parts per billion (w / w). This synergistic effect of TSNA reduction was also surprisingly found to result from reduced thermogeneration of TSNAs when aerosol generating materials comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of less than 650 parts per billion (w / w) is heated.

[0006] In some embodiments, there is provided an aerosol generating material for use in an article for use with a non-combustible aerosol-provision device, the aerosol generating material comprising air cured tobacco material, a binder, and a pH modifying agent, wherein the total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of the tobacco material of the aerosol generating material is greater than 650 parts per billion (w / w).

[0007] According to a second aspect of the present disclosure, there is provided a method of producing a reconstituted tobacco material for use in or as an aerosol generating material of the first aspect, the method comprising: (a) producing a dough or slurry comprising tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w); and (b) drying the dough or slurry to produce the reconstituted tobacco material.

[0008] According to a third aspect of the present disclosure, there is provided a method of producing a tobacco material for use in or as an aerosol generating material of the first aspect, the method comprising applying a coating to tobacco material, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w), and wherein the coating comprises a binder and a pH modifying agent.

[0009] According to a fourth aspect of the present disclosure, there is provided an aerosol generating material produced, obtained, or obtainable by the method of the second and / or third aspects.

[0010] According to a fifth aspect of the present disclosure, there is provided a component for a delivery system, wherein the component comprises aerosol generating material of the first aspect, or produced, obtained, or obtainable by the method of the second and / or third aspects.

[0011] The component may be for an aerosol provision system.

[0012] According to a sixth aspect of the present disclosure, there is provided a product comprising a component according to the fifth aspect.

[0013] The product may be a non-combustible aerosol provision system. The non-combustible aerosol provision system may be an aerosol generating material heating system, also known as a heat-not-burn system. The non-combustible aerosol provision system may be a tobacco heating system.

[0014] According to a seventh aspect of the present disclosure, there is provided an article comprising an aerosol generating material of the first aspect, or produced, obtained, or obtainable by the method of the second and / or third aspects.

[0015] According to a ninth aspect of the present disclosure, there is provided a system comprising an aerosol-generating material of the first aspect and a device arranged to heat the aerosol-generating material and generate an aerosol from the aerosol-generating material.

[0016] According to a tenth aspect of the present disclosure, there is provided the use of the combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco material to reduce the TSNA content, but not the aroma content, of the aerosol generated when the aerosol generating material is heated, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w).

[0017] According to an eleventh aspect of the present disclosure, there is provided a method of reducing the level of TSNA, without reducing the aroma, of an aerosol generated when a tobacco-containing aerosol generating material comprising a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w) is heated, the method comprising including a binder and a pH modifying agent in or on the aerosol generating material.

[0018] According to a twelfth aspect of the present disclosure, there is provided the use of the combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco material to reduce the thermogeneration of TSNAs when the aerosol generating material is heated, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w).TSNAs

[0019] The aerosol that is generated when tobacco-containing aerosol generating materials are heated includes tobacco specific nitrosamines (TSNA).

[0020] TSNA are nitrosation products of endogenous pyridine alkaloids like nicotine and nornicotine. The most commonly studied TSNA are: N'-nitrosonornicotine (NNN); 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK); N'-nitrosoanabasine (NAB); and N'-nitrosoanatabine (NAT).

[0021] TSNA are naturally present at low levels, or not at all, in fresh green tobacco and increase during curing, storage, fermentation, and processing of harvested tobacco leaves, in particular, during the tobacco curing process, generally due to nitrosation of nicotine and related tobacco alkaloids.

[0022] TSNAs may become present in the aerosol generated when a tobacco-containing aerosol generating material is heated as a result of processes including thermogeneration (pyrosynthesis) of TSNA and the transfer efficiency of TSNA from the tobacco material to the aerosol emission (pyrorelease).Tobacco Materials

[0023] As used herein, the term "tobacco material" refers to any material comprising tobacco.

[0024] The inventors have found that the TSNA content of an aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0025] Since TSNAs are produced during the tobacco curing process from alkaloids that may be present in different amounts in different tobacco strains and cultivars, different cured tobacco blends may have different levels of TSNAs.

[0026] The tobacco material comprises a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w).

[0027] Thus, in some embodiments, the total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of the tobacco material of the aerosol generating material may be greater than 650 parts per billion (w / w).

[0028] The tobacco material may comprise a tobacco blend. Unless otherwise indicated, references to a "blend" refer to a mixture of tobacco materials. The tobacco materials may comprise different varieties of tobacco, differently cured tobaccos (e.g. flue-cured, air-cured, sun-cured, fired-cured), different tobacco formats (e.g. lamina, reconstituted tobacco) and / or and different parts of the tobacco (e.g leaf, stem). The tobacco materials may be present in various different proportions (from 0.1% to 99.9%).

[0029] Preferably, the blend does not comprise tobacco having a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of less than 650 parts per billion (w / w).

[0030] In addition to comprising a content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), in some embodiments, the tobacco material may comprise a NNK content greater than 120 parts per billion (w / w).

[0031] In some embodiments, the tobacco material may comprise a NNN content greater than 120 parts per billion (w / w).

[0032] Typically, air cured tobaccos comprise a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w). Thus, in some embodiments, the aerosol generating material may comprise air-cured tobacco. Air-cured tobacco is hung in ventilated units and allowed to dry over a period of four to eight weeks. Air-cured tobacco has a high nicotine content.

[0033] The aerosol generating material may comprise Burley tobacco, which is a light air-cured tobacco.

[0034] However, the tobacco material may comprise tobacco material cured using any method, including, for example, flue cured, providing the tobacco material comprises a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w).

[0035] Significant reductions in the TSNA content of the aerosol generated when the aerosol generating material is heated have been found to occur when the tobacco of the aerosol generating material comprises a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w).

[0036] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0037] The TSNA content of the aerosol generated when the aerosol generating material of some embodiments is heated may be greater than 20%, 25%, 30%, 35%, or 40% lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0038] References to the "TSNA content" as used herein may refer to the total content of NNN, NNK, NAB, and NAT of an aerosol or aerosol generating material.

[0039] Thus, the total content of NNN, NNK, NAB, and NAT content of the aerosol generated when the aerosol generating material of some embodiments is heated may be greater than 20%, 25%, 30%, 35%, or 40% lower than the total content of NNN, NNK, NAB, and NAT content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0040] In some embodiments, the NNN content of the aerosol generated when the aerosol generating material of some embodiments is heated may be greater than 20%, 25%, 30%, 35%, or 40% lower than the NNN content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0041] In some embodiments, the NNK content of the aerosol generated when the aerosol generating material of some embodiments is heated may be greater than 20%, 25%, 30%, 35%, or 40% lower than the NNK content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0042] In some embodiments, the NAB content of the aerosol generated when the aerosol generating material of some embodiments is heated may be greater than 20%, 25%, 30%, 35%, or 40% lower than the NAB content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0043] In some embodiments, the NAT content of the aerosol generated when the aerosol generating material of some embodiments is heated may be greater than 20%, 25%, 30%, 35%, or 40% lower than the NAT content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

[0044] Particularly significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have been found to occur when the binder comprises acacia gum, carboxymethyl cellulose, and / or xanthan gum. In some embodiments, the TSNA content is synergistically lower.

[0045] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder comprising or consisting of acacia gum, carboxymethyl cellulose, and / or xanthan gum, and a pH modifier, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower. Unless otherwise indicated, as used herein "synergistically lower", refers to a level that is lower than the combined level achieved using a binder and a pH modifying agent individually.

[0046] More significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have been found to occur when the binder comprises acacia gum.

[0047] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder comprising or consisting of acacia gum, and a pH modifier, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0048] Significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have also been found to occur when the pH modifying agent comprises a salt of carbonic acid, such as calcium carbonate and / or a salt of citric acid, such as sodium citrate.

[0049] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier comprising a salt of carbonic acid, such as calcium carbonate and / or a salt of citric acid, such as sodium citrate, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0050] More significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have been found to occur when the pH modifying agent comprises a salt of citric acid, such as sodium citrate.

[0051] Thus, in some embodiments, the TSNA content of an aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier comprising a salt of citric acid, such as sodium citrate, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0052] Even more significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have been found to occur when the binder comprises acacia gum, carboxymethyl cellulose, and / or xanthan gum, and the pH modifying agent comprises a salt of citric acid, such as sodium citrate.

[0053] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder comprising or consisting of acacia gum, carboxymethyl cellulose, and / or xanthan gum, and a pH modifier comprising a salt of citric acid, such as sodium citrate, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0054] Even more significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have been found to occur when the when the binder comprises acacia gum and the pH modifying agent comprises a salt of carbonic acid, such as calcium carbonate and / or a salt of citric acid, such as sodium citrate.

[0055] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder comprising or consisting of acacia gum, and a pH modifier comprising or consisting of a salt of carbonic acid, such as calcium carbonate and / or a salt of citric acid, such as sodium citrate, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0056] Yet more significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated have been found to occur when the when the binder comprises acacia gum and the pH modifying agent comprises a salt of citric acid, such as sodium citrate.

[0057] Thus, in some embodiments, the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder comprising or consisting of acacia gum, and a pH modifier comprising or consisting of a salt of citric acid, such as sodium citrate, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. In some embodiments, the TSNA content is synergistically lower.

[0058] In some embodiments, the tobacco blend comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) may consist of or comprise a Burley tobacco blend.

[0059] In some embodiments, the generated aerosol may comprise reduced levels of: (a) NAB; (b) NAT; (c) NNK; and / or (d) NNN.

[0060] Thus, in some embodiments, the level of: (a) NAB; (b) NAT; (c) NNK; and / or (d) NNN,

[0061] in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated is lower than the level in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0062] In some embodiments, the level of at least one TSNA in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated is lower than the level of the at least one TSNA in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0063] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0064] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0065] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0066] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0067] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0068] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0069] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0070] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0071] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0072] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0073] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0074] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0075] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0076] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0077] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0078] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0079] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0080] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0081] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0082] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0083] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0084] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0085] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0086] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising a natural gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0087] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0088] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0089] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0090] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising acacia gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0091] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0092] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0093] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0094] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising xanthan gum, and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0095] In some embodiments, the level of NAB in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising carboxymethyl cellulose (CMC), and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAB in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0096] In some embodiments, the level of NAT in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising carboxymethyl cellulose (CMC), and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NAT in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0097] In some embodiments, the level of NNK in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising carboxymethyl cellulose (CMC), and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNK in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.

[0098] In some embodiments, the level of NNN in an aerosol generated when the aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder consisting of or comprising carboxymethyl cellulose (CMC), and a pH modifier consisting of or comprising a salt of citric acid, such as sodium citrate, is heated is lower than the level of NNN in an aerosol generated by equivalently heating an equivalent aerosol generating material that does not comprise a binder and a pH modifying agent. In some embodiments, the level is synergistically lower.Binder

[0099] In some embodiments, the binder may consist of or comprise a gum. In some embodiments, the binder may consist of or comprise a natural gum. For example, in some embodiments, the binder may consist of or comprise acacia gum, guar gum, locust bean gum, tamarind gum, and / or xanthan gum.

[0100] In some embodiments, the binder may consist of or comprise carboxymethyl cellulose (CMC).

[0101] In some embodiments, the binder may consist of or comprise acacia gum, xanthan gum, and / or carboxymethyl cellulose (CMC).

[0102] The use of a combination of one or more of these binders with a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) has been found to provide significant reductions in the TSNA content of the aerosol generated when the aerosol generating material is heated, relative to an equivalent material lacking a binder and pH modifying agent.

[0103] Surprisingly, the levels of compounds that contribute to the aroma and flavour of the aerosol were not found to be correspondingly reduced.

[0104] The use of one or more these specific binders in combination with a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) may, therefore, surprisingly provide a method for reducing TSNA content of the aerosol generated when the aerosol generating material is heated, without affecting the consumer experience.

[0105] In some embodiments, the binder consists of or comprises acacia gum and / or xanthan gum. Particularly significant reductions were found to be provided when the binder consists of or comprises acacia gum and / or xanthan gum.

[0106] In some embodiments, the binder consists of or comprises acacia gum, which has been found to provide the most significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) is heated.

[0107] Acacia gum, which is also known as gum Arabic, meska or chaar gund, is made of the sap taken from two species of acacia tree (Acacia seyal and Acacia senegal). The main component is arabin, which is the calcium salt of the polysaccharide arabic acid.

[0108] A combination of binders, such as a combination of two or three binders may be used.

[0109] The aerosol generating material may comprise a binder in a total amount of 1-20% by mass of the aerosol generating material. Preferably, the binder may comprise 2-15% by mass of the aerosol generating material.

[0110] In embodiments in which the binder comprises acacia gum, the aerosol generating material may comprise a binder in a total amount of less than 20% by mass of the aerosol generating material. Preferably, the binder may comprise less than 15% by mass of the aerosol generating material.

[0111] In embodiments in which the binder comprises acacia gum, the aerosol generating material may comprise a binder in a total amount of greater than 10% by mass of the aerosol generating material. Preferably, the binder may comprise greater than 11% by mass of the aerosol generating material. In some embodiments, the binder may comprise acacia gum in an amount of greater than 11% by mass of the aerosol generating material.pH Modifying Agent

[0112] In some embodiments, the pH modifying agent may consist of or comprise a pH modifier or a combination of different pH modifiers.

[0113] The pH modifier may be a basic pH modifier. The pH modifier may consist of or comprise any salt that is capable of acting as a pH modifier.

[0114] In some embodiments, the pH modifying agent may consist of or comprise a salt of a weak acid.

[0115] In some embodiments, the pH modifying agent may consist of or comprise a salt of citric acid, such as sodium citrate. In some embodiments, the citric acid salt may consist of or comprise monosodium citrate, disodium citrate, trisodium citrate, and / or calcium citrate, for example.

[0116] In some embodiments, the pH modifying agent may consist of or comprise a salt of carbonic acid, such as calcium carbonate. In some embodiments, the carbonic acid salt may consist of or comprise calcium carbonate, sodium carbonate and / or magnesium carbonate, for example.

[0117] The use of a combination of one or more of these pH modifying agents in combination with a binder in an aerosol generating material has been found to provide significant reductions in the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) is heated.

[0118] Surprisingly, it was found that the levels of compounds that contribute to the aroma and flavour of the aerosol were not correspondingly reduced.

[0119] The use of one or more these specific pH modifying agents in combination with a binder in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) may, therefore, surprisingly provide a method for reducing TSNA content of the aerosol generated when the aerosol generating material is heated, without affecting the consumer experience.

[0120] A combination of pH modifying agents, such as a combination of two or three pH modifying agents may be used.

[0121] The aerosol generating material may comprise a pH modifying agent in a total amount of 2-10% by mass of the aerosol generating material. Preferably, the pH modifying agent may comprise 3-8% by mass of the aerosol generating material.

[0122] The amount of pH modifier may be determined on the basis of the required pH of the final formulation of the aerosol generating material. For example, in some embodiments, the final formation may comprise pH modifier in an amount suitable to provide a pH in the range of pH 5.0 to pH 7.0, preferably from pH 5.5 to pH 6.5.

[0123] The amount of pH modifier may be determined on the basis of the required pH of the vapour or aerosol generated when the aerosol generating material is used. For example, in some embodiments, the aerosol generating material may comprise pH modifier in an amount suitable to provide a vapour or aerosol generated in use having a pH in the range of pH 6.0 to pH 7.0.

[0124] In some embodiments, the pH modifier may be an acid.

[0125] In some embodiments, the acid may be selected from the group consisting of lactic acid, levulinic acid, benzoic acid, citric acid, 2-methylbutyric acid, or 2-methylvaleric acid. In some embodiments, the acid is lactic acid. In some embodiments, the acid is levulinic acid. The term lactic acid is synonymous with the term 2-hydroxypropanoic acid and covers both D and L enantiomers separately or a mixture thereof. For example, the lactic acid can be a mixture (for example a racemic mixture) of D-2-hydroxypropanoic acid and L-2-hydroxypropanoic acid. The term levulinic acid is synonymous with the term 4-oxopentanoic acid.

[0126] In some embodiments, including some embodiments in which the active substance comprises nicotine, the inclusion of an acid has been found to additionally improve the release of other substances, such as active substances including nicotine, from the material.Aerosol Generating Material

[0127] The disclosed aerosol generating material comprises tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w).

[0128] In some embodiments, the aerosol generating material may comprise tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, or even 1200 parts per billion (w / w).

[0129] In addition to the tobacco material, the aerosol generating material comprises a combination of a binder and a pH modifying agent. The inventors have surprisingly discovered that the inclusion of a combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) significantly reduces the TSNA content of the aerosol generated upon heating of the aerosol generating material in comparison to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent. In some embodiments, the TSNA content is synergistically reduced.

[0130] Advantageously, despite the disclosed aerosol generating material providing a reduced TSNA level in the aerosol emission generated when the material is heated, the content of taste and / or aroma compounds of the aerosol is not substantially altered.

[0131] The level of taste and / or aroma of the vapour and / or aerosol generated by the aerosol generating material in use may be measured in terms of the total of the odour activity values (OAVs) of the aerosol.

[0132] In some embodiments, the inclusion of a combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) reduces the total OAV of the aerosol generated upon heating of the aerosol generating material by less than 10% in comparison to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.

[0133] In some embodiments, the inclusion of a combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) reduces the total OAV of the aerosol generated upon heating of the aerosol generating material by less than 5% in comparison to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.

[0134] In some embodiments, the inclusion of a combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) does not alter or does not significantly alter the aerosol generated upon heating of the aerosol generating material in a manner that can be detected by the user, in comparison to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.

[0135] In some embodiments, the inclusion of a combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w) reduces the total OAV of the aerosol generated upon heating of the aerosol generating material by less than the reduction in the TSNA content of the aerosol generated when the material is heated, in comparison to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.

[0136] Unless otherwise indicated, an "aerosol generating material" is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way.

[0137] 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.Form of Tobacco Material

[0138] The term "tobacco material" may include one or more of tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco, or tobacco-containing substitute materials.

[0139] Regardless of the form in which the tobacco material is included in the aerosol generating material, the tobacco comprises a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w).

[0140] The tobacco material may comprise one or more of ground tobacco, tobacco fibre, cut tobacco, tobacco leaf, tobacco lamina, extruded tobacco, tobacco stem, reconstituted tobacco and / or tobacco extract.

[0141] In some embodiments, the tobacco material may comprise tobacco lamina.

[0142] The aerosol generating material may comprise any type of tobacco, such as single grades or blends, cut rag or whole leaf.

[0143] The tobacco material may comprise tobacco particle 'fines' or dust, expanded tobacco, stems, expanded stems, and other processed stem materials, such as cut rolled stems.

[0144] The tobacco material may be a reconstituted tobacco material. The reconstituted tobacco material may comprise tobacco fibres, and may be formed by casting, a paper making-type approach with back addition of tobacco extract, or by extrusion, for example.

[0145] A composition comprising the binder and / or pH modifier may be applied to the tobacco material, for example as a coating.

[0146] In embodiments in which the tobacco material comprises reconstituted tobacco material, the binder and / or pH modifier may additionally or alternatively be included as a component of the reconstituted tobacco material.

[0147] The tobacco material may be provided in the form of cut rag tobacco. The cut rag tobacco can have a cut width of at least 15 cuts per inch (about 5.9 cuts per cm, equivalent to a cut width of about 1.7mm). Preferably, the cut rag tobacco has a cut width of at least 18 cuts per inch (about 7.1 cuts per cm, equivalent to a cut width of about 1.4mm), more preferably at least 20 cuts per inch (about 7.9 cuts per cm, equivalent to a cut width of about 1.27mm). In one example, the cut rag tobacco has a cut width of 22 cuts per inch (about 8.7 cuts per cm, equivalent to a cut width of about 1.15mm). Preferably, the cut rag tobacco has a cut width at or below 40 cuts per inch (about 15.7 cuts per cm, equivalent to a cut width of about 0.64mm). Cut widths between 0.5 mm and 2.0 mm, for instance between 0.6 mm and 1.5 mm, or between 0.6 mm and 1.7mm, have been found to result in tobacco material which is preferable in terms of surface area to volume ratio, particularly when heated, and the overall density and pressure drop of the aerosol generating material.

[0148] The cut rag tobacco may be formed from a mixture of forms of tobacco material, for instance a mixture of one or more of paper reconstituted tobacco, leaf tobacco, extruded tobacco and bandcast tobacco.

[0149] The tobacco material may comprise reconstituted tobacco material.

[0150] In some embodiments, the tobacco material may comprise a blend of reconstituted tobacco material and another form of tobacco material, such as a tobacco material comprising tobacco lamina.

[0151] The aerosol generating material may comprise reconstituted tobacco material having a density of less than about 700 milligrams per cubic centimetre (mg / cc). Such tobacco material has been found to be particularly effective at providing an aerosol generating material which can be heated quickly to release an aerosol, as compared to denser materials. For each given aerosol generating material, there is a particular zero heat flow temperature below which net heat flow is endothermic, (i.e. more heat enters the material than leaves the material), and above which net heat flow is exothermic (i.e. more heat leaves the material than enters the material), while heat is applied to the material. Materials having a density less than 700 mg / cc have a lower zero heat flow temperature. Since a significant portion of the heat flow out of the material is via the formation of aerosol, having a lower zero heat flow temperature has a beneficial effect on the time it takes to first release aerosol from the aerosol generating material. For instance, aerosol generating materials having a density of less than 700 mg / cc were found to have a zero heat flow temperature of less than 164°C, as compared to materials with a density over 700 mg / cc, which had zero heat flow temperatures greater than 164°C.

[0152] The density of the aerosol generating material also has an impact on the speed at which heat conducts through the material, with lower densities, for instance those below 700 mg / cc, conducting heat more slowly through the material, and therefore enabling a more sustained release of aerosol.

[0153] The aerosol generating material may comprise reconstituted tobacco material having a density of less than about 700 mg / cc, for instance paper reconstituted tobacco material. More preferably, the aerosol generating material comprises reconstituted tobacco material having a density of less than about 600 mg / cc. Alternatively, or in addition, the aerosol generating material preferably comprises reconstituted tobacco material having a density of at least 350 mg / cc, which is considered to allow for a sufficient amount of heat conduction through the material.

[0154] Paper reconstituted tobacco may be present in the aerosol generating material described herein in an amount of from 10% to 100% by weight of the aerosol generating material. Preferably, the aerosol generating material comprises reconstituted tobacco material in an amount of between about 70% and about 90% by weight of the aerosol generating material. In a further embodiment, the aerosol generating material consists essentially of, consists of, or comprises, paper reconstituted tobacco.

[0155] Paper reconstituted tobacco refers to tobacco material formed by a process in which tobacco feedstock is extracted with a solvent to afford an extract of solubles and a residue comprising fibrous material, and then the extract (usually after concentration, and optionally after further processing) is recombined with fibrous material from the residue (usually after refining of the fibrous material, and optionally with the addition of a portion of non-tobacco fibres) by deposition of the extract onto the fibrous material. The process of recombination resembles the process for making paper.

[0156] The paper reconstituted tobacco may be any type of paper reconstituted tobacco that is known in the art. In a particular embodiment, the paper reconstituted tobacco is made from a feedstock comprising one or more of tobacco strips, tobacco stems, and whole leaf tobacco. In a further embodiment, the paper reconstituted tobacco is made from a feedstock consisting of tobacco strips and / or whole leaf tobacco, and tobacco stems. However, in other embodiments, scraps, fines and winnowings can alternatively or additionally be employed in the feedstock.

[0157] The paper reconstituted tobacco for use in the aerosol generating material described herein may be prepared by methods which are known to those skilled in the art for preparing paper reconstituted tobacco.Reconstituted Tobacco Material

[0158] The reconstituted tobacco material may be formed from a dough or slurry comprising the pH modifying agent, the binder, the tobacco material, and optionally an aerosol forming material.

[0159] The reconstituted tobacco material may be produced by a method comprising the formation of a dough or slurry including the binder and the pH modifying agent and further comprising the tobacco material, an aerosol forming material, and any other components as required, such as, for example, cellulose fibre.

[0160] The dough or slurry may be cast using conventional means, for example on a casting sheet, and dried using conventional means and conditions, for example in an oven using a temperature of about 80°C for about 90 minutes. The resultant sheets may then be conditioned using conventional means, for example, a conditioning cabinet at about 60% relative humidity and 22°C for up to about 24, or longer if required, for example, 48 hours.Application to Tobacco Material

[0161] The binder and / or the pH modifying agent may be present in a coating on the aerosol generating material.

[0162] For example, a composition comprising the binder and / or pH modifier may be applied to the tobacco material, reconstituted tobacco material, and / or aerosol generating material. The composition may be applied, for example, as a coating.

[0163] As used herein, the terms "coating" and "coated" refer to the presence of a non-particulate or substantially non-particulate covering on the surface of the tobacco material, reconstituted tobacco material, and / or aerosol generating material.

[0164] In some embodiments, the composition may be absorbed into the leaf pores or other internal features of the tobacco material, reconstituted tobacco material, and / or aerosol generating material.

[0165] In some embodiments the coating may be a partial coating, in that it covers a percentage of the surface of the tobacco material, reconstituted tobacco material, and / or aerosol generating material. The percentage may be less than 100%, and may, for example, be less than 90%, 80%, 70%, or 60% of the surface of the material. The percentage may be greater than 55%, and may, for example, be greater than 65%, 75%, 85%, or 95% of the surface of the material.

[0166] In other embodiments, the coating may be a complete coating in that it covers all or substantially all of the surface of the tobacco material, reconstituted tobacco material, and / or aerosol generating material.

[0167] The composition may be applied to the tobacco material, reconstituted tobacco material, and / or aerosol generating material by any suitable method.

[0168] In some embodiments, the composition may be sprayed onto the tobacco material, reconstituted tobacco material, and / or aerosol generating material, for example, the solution may be sprayed onto a falling curtain of the material.

[0169] In some embodiments, the tobacco material, reconstituted tobacco material, and / or aerosol generating material may be immersed in the composition.Additional Components

[0170] In addition to a binder and a pH modifying agent, the aerosol generating material may comprise one or more further components.

[0171] In some embodiments, the aerosol generating material may comprise a botanical material, an active substance, such as a flavourant, and / or an aerosol forming material.Botanical Material

[0172] As used herein, the term "botanical material" refers to any material derived from a plant, and includes any material derived from any plant part including, but not limited to, leaves, bark, buds, fibres, stems, roots, seeds, flowers, fruits, pollen, husk, and / or shells.

[0173] The botanical material is present in addition to tobacco material and as such may be referred to as "non-tobacco botanical material". Unless otherwise indicated, references herein to "botanical material" refer to non-tobacco botanic material.

[0174] Tobacco material is any material from a plant from the genus Nicotiana.

[0175] Non-tobacco botanical material is any material derived from any plant that is not a plant from the genus Nicotiana. Thus, non-tobacco botanical material includes, but is not limited to, 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, cinnamon, coffee, aniseed (anise), basil, bay leaves, cardamom, coriander, cumin, nutmeg, oregano, paprika, rosemary, saffron, clove, 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.

[0176] The botanical material may be a material derived from species which are members of the Asteraceae family, the Fabaceae family, the Myrtaceae family, Apiaceae family, Camellia taliensis, the Solanaceae family, the Brassicaceae family, the Caricaceae family, the Asclepiadaceae family, the Equisetaceae family, the Oleaceae family, the Lamiaceae family, and tisanes. The non-tobacco botanical material may be selected from the Matricaria species, such as chamomile; the Pimpinella anisum species, such as anise; the Foeniculum vulgare species, such as fennel; jasmine; lavender; cloves; eucalyptus, and the species Aspalathus linearis, such as rooibos.

[0177] The botanical material may be an aromatic botanical material. In this context, "aromatic" refers to any material having a distinctive smell. Thus, an aromatic botanical material is any material that is capable of being identified by its aroma. The botanical material may comprise or consist of an active substance that is a flavourant, and thus the botanical material may be a flavourant botanical material. The botanical material is preferably an aromatic flavourant botanical material.

[0178] In some embodiments, the botanical material may comprise favourable aroma properties for use in a non-combustible aerosol provision system. For example, the botanical material may deliver an aerosol which is considered favourable by a consumer of tobacco-based delivery systems when used in a non-combustible aerosol provision system. For example, the botanical material may comprise an active substance that is an active substance found in tobacco, such as nicotine or a tobacco flavourant.

[0179] In some embodiments, the botanical material may comprise or consist of mint, chamomile, eucalyptus, lavender, ginger, rooibos, cinnamon, star anise, cocoa, hemp, fennel, and / or clove material.

[0180] 'Mint', 'mint material', and 'mint botanical material' refers to any material derived from a plant from the genus Mentha in the family Lamiaceae. Any plant from this genus may be referred to as a 'mint plant'. The mint botanical material may comprise or consist of material 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. The mint botanical material may comprise material from any part of a mint plant, and preferably, the mint botanical material may comprise or consist of mint leaf and / or mint stem material. In terms of an active substance, the mint botanical material may comprise menthol.

[0181] 'Chamomile', 'chamomile material', and 'chamomile botanical material' refers to any material derived from a plant from the genus Asteraceae, which contains various daisy-like plants. Any plant or tree from this genus may be referred to as a 'chamomile plant'. The chamomile botanical material may comprise material from any part of a chamomile plant, and preferably, the chamomile botanical material may comprise or consist of chamomile flower material. In terms of an active substance, the chamomile botanical material may comprise, for example, apigenin, quercetin, patuletin, and / or luteolin.

[0182] 'Eucalyptus', 'eucalyptus material', and 'eucalyptus botanical material' refers to any material derived from a plant from the genus Eucalyptus, which contains various species of flowering trees, shrubs or mallees in the myrtle family, Myrtaceae. Any plant or tree from this genus may be referred to as a 'eucalyptus plant' or 'eucalyptus tree'. The eucalyptus botanical material may comprise material from any part of a eucalyptus tree, and preferably, the eucalyptus botanical material may comprise or consist of eucalyptus leaf and / or eucalyptus stem and / or eucalyptus flower material. In terms of an active substance, the eucalyptus botanical material may comprise cineole.

[0183] 'Lavender', 'lavender material', and 'lavender botanical material' refers to any material derived from a plant from the genus Lavandula in the family Lamiaceae. Any plant from this genus may be referred to as a 'lavender plant'. The lavender botanical material may comprise material from any part of a lavender plant, and preferably, the lavender botanical material may comprise or consist of lavender flower and / or lavender bud material. In terms of an active substance, the lavender botanical material may comprise, for example, limonene, linalool, linalyl acetate, and / or camphor.

[0184] 'Ginger', ginger material', and ginger botanical material' refers to any material derived from a plant from the genus Zingiber in the family Zingiberaceae. Any plant from this genus may be referred to as a ginger plant'. Preferably, the ginger plant is Zingiber officinale, which is a flowering plant whose rhizome, known as ginger root or ginger, is widely used as a spice. The ginger botanical material may comprise material from any part of a ginger plant, and preferably, the ginger botanical material may comprise or consist of ginger root / rhizome material. In terms of an active substance, the ginger botanical material may comprise, for example, sesquiterpene hydrocarbons, gingerol, shogaol, and / or oleoresin.

[0185] 'Rooibos, 'rooibos material', and 'rooibos botanical material' refers to any material derived from a plant from the genus Aspalathus, and in particular, Aspalathus linearis, in the family Fabaceae. Preferably, the rooibos plant is Aspalathus linearis, which is a bush whose leaves are widely used to make tea, known as bush tea, red tea, or redbush tea. The rooibos botanical material may comprise material from any part of a rooibos plant, and preferably, the rooibos botanical material may comprise or consist of rooibos leaf material. In terms of an active substance, the rooibos botanical material may comprise vitamin C, and / or polyphenols, including flavanols, flavones, flavanones, dihydrochalcones, aspalathin, and / or nothofagin. The rooibos botanical material may additionally or alternatively comprise benzoic and / or cinnamic acids.

[0186] 'Cinnamon', 'cinnamon material', and 'cinnamon botanical material' refers to any material derived from a plant from the genus Cinnamomum in the family Lauraceae. Cinnamon is a spice obtained from the inner bark of various tree species from this genus, and any tree from this genus may be referred to as a 'cinnamon plant' or 'cinnamon tree'. The cinnamon botanical material may comprise material from any part of a cinnamon plant, and preferably, the cinnamon botanical material may comprise or consist of cinnamon bark material. In terms of an active substance, the cinnamon botanical material may comprise, for example cinnamaldehyde, trans-cinnamaldehyde (cin), procyanidins, and / or catechins.

[0187] 'Star anise', 'star anise material', and 'star anise botanical material' refers to any material derived from a plant from the species Illicium verum. Star anise is a spice obtained from the fruit of the plant, and the star anise botanical material may comprise or consist of star anise fruit material. In terms of an active substance, the star anise botanical material may comprise anethole.

[0188] 'Cocoa', 'cocoa material', and 'cocoa botanical material' refers to any material derived from a plant from the species Theobroma cacao. Cocoa is obtained from the seed of the plant. The cocoa botanical material may comprise or consist of cocoa seed material. In terms of an active substance, the cocoa botanical material may comprise an alkaloid, which may be theobromine, also known as xantheose.

[0189] 'Hemp, 'hemp material', and 'hemp botanical material' refers to a botanical class of Cannabis sativa cultivars grown specifically for industrial or medicinal use. The hemp botanical material may comprise material from any part of a hemp plant, and preferably, the hemp botanical material may comprise or consist of hemp seed, leaf, and / or fibre material. In terms of an active substance, the hemp botanical material may comprise tetrahydrocannabinol (THC) and / or cannabidiol (CBD).

[0190] 'Fennel', 'fennel material', and 'fennel botanical material' refers to any material derived from a plant from the species Foeniculum vulgare. Fennel is a highly flavorful herb comprising volatile oils imparting mixed aromas. The fennel botanical material may comprise material from any part of a fennel plant, and preferably, the fennel botanical material may comprise or consist of fennel bulb, seed, umbel, and / or flower material. In terms of an active substance, the fennel botanical material may comprise trans-anethole, estragole, fenchone, limonene, 1-octen-3-ol, and / or polyphenols, such as rosmarinic acid and / or luteolin.

[0191] 'Clove', 'clove material', and 'clove botanical material' refers to any material derived from a plant from the species Syzygium aromaticum, which may be referred to as a 'clove plant' or'clove tree'. The clove botanical material may be derived from the bud of the clove plant material. The clove material may include, but is not limited to, the following type of clove material: Jawa, Bali, Manado, and / or Manado second grade. The use of clove material may provide a distinctive flavour and sensorial experience for the end user. Cloves are known to have sensory effects including aroma, spicy, numbing, crackling, and throat soothing features among others. In terms of an active substance, the clove botanical material may comprise eugenol.

[0192] In some embodiments, the botanical material may comprise material from seed-producing plants which do not develop persistent woody tissue and which are often valued for their medicinal or sensorial characteristics.

[0193] In some embodiments, the botanical material may produce an aerosol, when heated, with a sensorial experience that is comparable to that provided by a conventional combustible product, such as a cigarette.

[0194] In some embodiments, the botanical material may be a reconstituted botanical material.

[0195] In some embodiments, the botanical material may comprise a combination of botanical materials, such as a combination of two or more, such as two, three, four, five, or six, botanical materials.

[0196] The botanical material may be a material that naturally contains or comprises an active substance.Active Substance

[0197] In some embodiments, the aerosol generating material comprises an active substance. An "active substance" may also be referred to as an "active material" herein.

[0198] The active substance may create a physiological or sensory effect on the human body. Example active substances are flavourants and sensate materials. A sensate material creates an organoleptic sensation that can be perceived through the senses, such as a cool or sour sensation.

[0199] In some embodiments, the active substance may be a physiologically active material. A "physiologically active material" as used herein refers to a material intended to achieve or enhance a physiological response. The active substance may for example be selected from nutraceuticals, nootropics, psychoactives.

[0200] The active substance may be derived from a botanical material as defined herein. For example, the active substance may be a constituent, derivative or extract of a botanical material.

[0201] In some embodiments, the active substance may be derived from tobacco.

[0202] In some embodiments, the active substance comprises nicotine.

[0203] In some embodiments, the active substance is derived from cannabis.

[0204] In some embodiments, the active substance comprises one or more cannabinoids or terpenes.

[0205] In some embodiments, the active substance is derived from a botanical material selected from mint, chamomile, eucalyptus, lavender, ginger, rooibos, cinnamon, star anise, cocoa, hemp, fennel, and / or clove material. The active substance may be any one or more of those listed herein in relation to these botanical materials.

[0206] The active substance may be naturally present in tobacco or another botanical material. For example, the active substance may be nicotine that is naturally present in tobacco material.

[0207] The active substance may be added to the aerosol generating material. For example, the active substance may be added to the aerosol generating material before, during or after the production of the material. The active substance may be added to the aerosol generating material by any suitable method such as spraying, dipping, or coating.

[0208] The active substance may be a naturally occurring substance.

[0209] The active substance may be synthetic and / or chemically produced.

[0210] In some embodiments, the active substance may comprise nicotine, caffeine, taurine, theine, vitamins such as B6 or B12 or C, melatonin, cannabinoids, or constituents, derivatives, or combinations thereof.

[0211] The active material may comprise nicotine (optionally contained in tobacco or a tobacco derivative) or one or more other non-olfactory physiologically active materials. As used herein, the term "non-olfactory physiologically active material" refers to a material which is included in the aerosol generating material in order to achieve a physiological response other than olfactory perception.

[0212] In some embodiments, the active substance may comprise a nicotine salt. The nicotine salt may be nicotine benzoate, nicotine levulinate, nicotine citrate, nicotine lactate, or combinations thereof.

[0213] In some embodiments, the active substance may comprise nicotine. Nicotine may be included in the material in a final amount of about 0.1% to about 5% by weight of the material. For example, the total amount of nicotine in the material may be from about 0.2% to about 4%, from about 0.5% to about 3, such as about 1% or about 2% by weight of the material.

[0214] The nicotine content may be determined by any suitable method, such as, for example, using gas chromatography, or any other method that is used in the art to quantify the level of secondary alkaloids in tobacco.

[0215] In some embodiments, the active substance is a legally permissible recreational drug.

[0216] The active substance may be CBD or a derivative thereof.Flavourants

[0217] The aerosol generating material may comprise an active substance that may be a flavourant. As used herein, the terms "flavour" and "flavourant" refer to materials which, where local regulations permit, may be used to create a desired taste or aroma in a product for adult consumers.

[0218] The active substance may consist of or comprise one or a combination of extracts (e.g., licorice, hydrangea, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, menthol, Japanese mint, aniseed, cinnamon, herb, wintergreen, cherry, berry, peach, apple, Drambuie, bourbon, scotch, whiskey, spearmint, peppermint, lavender, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, honey essence, rose oil, vanilla, lemon oil, orange oil, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, piment, ginger, anise, coriander, coffee, or a mint oil from any species of the genus Mentha), 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, oil, liquid, or powder.

[0219] Flavourant not reduced - Advantageously, despite the disclosed aerosol generating material providing a reduced TSNA level in the aerosol, the content of taste and / or aroma compounds of the aerosol is not substantially reduced relative to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.Aerosol Forming Material

[0220] The aerosol generating material may comprise an aerosol forming material.

[0221] In this context, an "aerosol forming material" is an agent that promotes the generation of an aerosol. An aerosol forming material 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. In some embodiments, an aerosol forming material may improve the delivery of flavour from the aerosol generating material.

[0222] The aerosol forming material is included in the aerosol generating material in a significantly higher level than the level used in products that are arranged to generate an aerosol by combustion. This is because in use in a non-combustible aerosol-provision device, the aerosol generating material is heated to a much lower temperature than in combustible products, such as to a temperature of 200-350°C. To ensure the generation of a satisfactory aerosol at this temperature, a greater content of aerosol forming material is required in the aerosol generating material relative to the level required in a combustible product.

[0223] In some embodiments, the aerosol generating material comprises an aerosol forming material in an amount of 5-25% by weight of the aerosol generating material.

[0224] In some embodiments, the aerosol forming material comprises at least 7% by weight of the aerosol generating material, more preferably at least 10%. Preferably, the aerosol forming material comprises less than 22% or less than 20% by weight of the aerosol generating material. In some embodiments, the aerosol forming material comprises between 12% and 25%, or between 15% and 20% by weight of the aerosol generating material.

[0225] In general, any suitable aerosol forming material or agents may be included in the aerosol generating material. Suitable aerosol forming materials include, but are not limited to: a polyol such as 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.

[0226] The aerosol forming material may comprise 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.

[0227] In some embodiments, the aerosol forming material may comprise glycerol, propylene glycol, or a mixture of glycerol and propylene glycol.Thin Film

[0228] The aerosol generating material may comprise or be a "thin film", which may also be referred to as an "amorphous solid" or a "dried gel". In some embodiments, the aerosol generating material comprises an aerosol-generating film that is a thin film. The thin film may be a "monolithic solid". The thin film may be substantially non-fibrous. In some embodiments, the thin film may be a dried gel. The thin film is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the thin film may, for example, comprise from about 50wt%, 60wt% or 70wt% of solid material, to about 90wt%, 95wt% or 100wt% of solid material.

[0229] The aerosol generating material is heated in use to generate an inhalable aerosol or vapour. The thin film may contain volatile components, such as nicotine and derivatives of nicotine, flavourants and aerosol forming materials. These volatiles in the thin film are volatilised in use and inhaled; the provision of the thin film allows the composition of the aerosol or vapour to be altered / enhanced In some embodiments, the thin film is or comprises a hydrogel.

[0230] In some embodiments, the thin film comprises less than about 20wt% of water calculated on a wet weight basis. In some cases, the thin film may comprise less than about 15wt%, 12wt% or 10 wt% of water calculated on a wet weight basis (WWB). In some cases, the thin film may comprise at least about 1wt%, 2wt% or at least about 5wt% of water (WWB).

[0231] In some embodiments, the thin film comprises less than about 10wt% or less than 5% of filler such as calcium carbonate calculated on a wet weight basis. Preferably, the thin film comprise no filler or essentially no filler.

[0232] The thin film may comprise an aerosol forming material in an amount of 5-80wt%, such as 10-50wt%.Component for delivery system

[0233] The aerosol generating material may be included in a component in an article for use with a non-combustible aerosol-provision device.

[0234] The component may comprise the disclosed aerosol generating material in a blend, for example, in combination with a second aerosol generating material. The second aerosol generating material may comprise a second tobacco material. The second aerosol generating material may comprise a non-tobacco botanical material.

[0235] The component may be configured such that the inclusion of the disclosed aerosol generating material in the component results in, during use of the component, the provision of an aerosol comprising a reduced TSNA content compared to components comprising an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.

[0236] Advantageously, despite the disclosed aerosol generating material providing a reduced TSNA level in the aerosol, the content of taste and / or aroma compounds of the aerosol is not substantially reduced relative to an equivalent aerosol generating material that does not comprise a combination of a binder and a pH modifying agent.Delivery System

[0237] The aerosol generating material may be included in an article, which may be an article comprising a component.

[0238] The article may be used in in a heating device. The heating device may be configured to heat the aerosol generating portion of the article.

[0239] In some embodiments, the heating device may comprise a cavity arranged to receive the aerosol generating portion of the article and to heat the aerosol generating portion.

[0240] In some embodiments, the heating device may be arranged to heat the aerosol generating portion to a temperature of between about 180 °C and 350 °C, preferably between about 200 °C and 300 °C.

[0241] In some embodiments, the heating device may be arranged to receive the aerosol generating portion and to heat the aerosol generating portion to generate an aerosol from the aerosol generating material.Description of Drawings

[0242] Embodiments of the invention are described, by way of example only, with reference to the accompanying drawings, in which: Figure 1a-d are graphs showing TSNA levels before and after heating a product comprising aerosol generating material comprising a rich tobacco blend (RTB), which is a tobacco blend comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), and different binders as indicated. For each binder group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 2a-c are graphs showing: (a) the total amounts of NNK, (b) the amount of matrix-bound NNK, and (c) the amount of free NNK, before and after heating a product comprising aerosol generating material comprising a rich tobacco blend (RTB), and different binders as indicated. For each binder group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 3a-d are graphs showing TSNA levels in the aerosol emission generated by heating a product comprising aerosol generating material comprising a rich tobacco blend (RTB), and different binders as indicated. Figure 4a-d are graphs showing TSNA levels before and after heating a product comprising aerosol generating material comprising a light tobacco blend (LTB), which is a tobacco blend comprising a total content of NNN, NNK, NAB, and NAT of less than 650 parts per billion (w / w), and different binders as indicated. For each binder group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 5a-c are graphs showing: (a) the total amounts of NNK, (b) the amount of matrix-bound NNK, and (c) the amount of free NNK, before and after heating a product comprising aerosol generating material comprising a light tobacco blend (LTB), and different binders as indicated. For each binder group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 6a-d are graphs showing TSNA levels in the aerosol emission generated by heating a product comprising aerosol generating material comprising a light tobacco blend (LTB), and different binders as indicated. Figure 7 and b are graphs showing retained % of TSNA after heating a product comprising aerosol generating material comprising (A) LTB or (B) RTB, and different binders as indicated. Figure 8a-d are graphs showing free TSNA levels before and after heating a product comprising aerosol generating material comprising a RTB and different binders as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 9a-d are graphs showing free TSNA levels before and after heating a product comprising aerosol generating material comprising a RTB, a binder, and different pH modifiers as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 10a-d are graphs showing TSNA levels before and after heating a product comprising aerosol generating material comprising a RTB and different binders and pH modifiers as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 11a-d are graphs showing TSNA levels in the aerosol emission generated by heating a product comprising aerosol generating material comprising a RTB and different binders and pH modifiers as indicated. Figure 12a-d are graphs showing: (a) the total amounts of NNK, (b) the amount of matrix-bound NNK, and (c) the amount of free NNK, before and after heating a product comprising aerosol generating material comprising a RTB and different binders and pH modifiers as indicated. For each binder group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 13a-d are graphs showing free TSNA levels before and after heating a product comprising aerosol generating material comprising a LTB and different binders as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 14a-d are graphs showing free TSNA levels before and after heating a product comprising aerosol generating material comprising a LTB, a binder, and different pH modifiers as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 15a-d are graphs showing TSNA levels before and after heating a product comprising aerosol generating material comprising a LTB and different binders and pH modifiers as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 16a-d are graphs showing: (a) the total amounts of NNK, (b) the amount of matrix-bound NNK, and (c) the amount of free NNK, before and after heating a product comprising aerosol generating material comprising a LTB and different binders and pH modifiers as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 17a-d are graphs showing TSNA levels in the aerosol emission generated by heating a product comprising aerosol generating material comprising a LTB and different binders and pH modifiers as indicated. Figure 18a-c are graphs showing the proportions of the differently protonated forms of nicotine (a) before heating, (b) in the aerosol emission generated by heating, and (c) after heating, a product comprising aerosol generating material comprising a RTB and different binders and pH modifiers as indicated. The top shaded section of each bar shows the proportion of unprotonated nicotine ([Nic]), the central shaded section of each bar shows the proportion of monoprotonated nicotine ([NicH +< ]), and the bottom (dark) shaded portion shows the proportion of diprotonated nicotine ([NicH ++< ]). Figure 19a-c are graphs showing the proportions of the differently protonated forms of nicotine (a) before heating, (b) in the aerosol emission generated by heating, and (c) after heating, a product comprising aerosol generating material comprising a LTB and different binders and pH modifiers as indicated. The top shaded section of each bar shows the proportion of unprotonated nicotine ([Nic]), the central shaded section of each bar shows the proportion of monoprotonated nicotine ([NicH +< ]), and the bottom (dark) shaded portion shows the proportion of diprotonated nicotine ([NicH ++< ]). Figure 20 is a graph showing total particulate matter levels in a product comprising tobacco lamina material comprising a RTB and acacia gum and / or citrate material as indicated. Figure 21a-d are graphs showing TSNA levels before and after heating a product comprising tobacco lamina material comprising a RTB and acacia gum and / or citrate as indicated. For each group the left-hand column shows pre-heating level and the right-hand column shows the post-heating level. Figure 22a-c are graphs showing TSNA levels in the aerosol emission generated by heating a product comprising tobacco lamina material comprising a RTB and acacia gum and / or citrate as indicated. Examples Example 1Tobacco preparation

[0243] Reconstituted tobacco products were prepared using a method comprising: 1. Grinding tobacco in a cutter mill; 2. Mixing the ground tobacco with cellulose fibre, glycerol, and binders in the proportions shown in Table 1 (values are % by mass) to form various different doughs; 3. Extruding and drying each dough to form a reconstituted tobacco material in the form of an extruded sheet. Table 1Reconstituted Tobacco Material No.123456789101112BlendRTB6060606060-----60-LTB-----6060606060-60Cellulose fibre202118222020211822201818Glycerol151515151515151515151515BinderCMC523--523----Xanthan-2-3--2-3-22Guar--4----4----Acacia----5----555

[0244] The "Rich" tobacco blend (RTB) had a total content of NAB, NAT, NNK, and NNN of greater than 650 ppb (w / w), and the content of each of NNK and NNN individually was greater than 120 ppb (w / w).

[0245] The RTB used consisted of Burley tobacco having a total content of NAB, NAT, NNK, and NNN of greater than 650 ppb (w / w), including a NNK content of greater than 120 ppb (w / w), and a NNN content of greater than 120 ppb (w / w).

[0246] The "Light" tobacco blend (LTB) had a total content of NAB, NAT, NNK, and NNN of less than 650 ppb (w / w), and the content of each of NNK and NNN individually was less than 120 ppb (w / w).

[0247] The LTB used consisted of a tobacco blend having a total content of NAB, NAT, NNK, and NNN of less than 650 ppb (w / w), including a NNK content of less than 120 ppb (w / w), and a NNN content of less than 120 ppb (w / w).Smoking Regime and Analysis

[0248] Tobacco product consumables in a super slim format, each comprising aerosol generating material comprising one of the reconstituted tobacco materials detailed in Table 1, were heated in an external heating non-combustible aerosol-provision device using the HCI (Health Canada Intense) smoking regimen and subjected to 8 puffs.

[0249] The amounts of TSNAs (NAB, NAT, NNN and NNK free and NNK matrix-bound) were analysed by LC-MS / MS as described in Lang, G., and Vuarnoz, A. (2015) Matrix-Bound 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone in Tobacco: Quantiification and Evidence for an Origin from Lignin-Incorporated Alkaloids. J. Nat. Prod. 78, 85-92.

[0250] Retention of TSNAs was calculated using the following equation (Equation 1):

[0251] The difference in the TSNA level pre- and post-heating reflects the level of TSNA generated upon heating of the material ("thermogeneration") minus the level of TSNA lost, for example in the emitted aerosol. Greater "Retained %" of a TSNA upon heating thus reflects greater thermogeneration and / or reduced emission of the TSNA.

[0252] Three replicate measurements of TSNA levels were carried out with three consumables per replicate.

[0253] NNK has been widely studied in both tobacco cured leaves and tobacco smoke. Initial studies found divergence of the amount of NNK in the tobacco before and after its pyrolysis. Recently, Lang and Vuarnoz developed a method to extract NNK from tobacco cured leaves, and using this method, the results of the total NNK extracted were closely related to the reported value of NNK in the tobacco smoke analysis. The results indicate that there are two compartments of NNK in tobacco leaves. In a first compartment NNK is labile and soluble in water, and in a second compartment NNK is bound to natural tobacco polymers. Matrix-bound NNK presented in tobacco leaf has been found to contribute to a large proportion of the mainstream smoke, which suggests that most of the NNK found in the mainstream smoke is derived from the matrix-bound NNK compartment, rather than soluble NNK.

[0254] In the present studies, Total NNK was quantified using LC-MS / MS based on the Lang and Vuarnoz method (Lang, G., and Vuarnoz, A. (2015) Matrix-Bound 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone in Tobacco: Quantification and Evidence for an Origin from Lignin-Incorporated Alkaloids. J. Nat. Prod. 78, 85-92). The extraction procedure was performed using ca. 750 mg of powdered samples and Tris-HCl buffer solution (30 mL; 50 mmol·L-1 ; pH 7.5) with added internal standard (NNKd4). Samples were extracted in autoclave at 130 °C, 275 kPa for 4 h. Extracted solutions were filtered (0.20 µm PTFE) and injected in LC MS / MS. Analyses were carried out on an Agilent HPLC 1200 system (Agilent, USA) coupled to a triple-quadrupole mass spectrometer (TQMS) (Applied Biosystem API 4000, Agilent, USA), with electrospray ionization (ESI). A Poroshell 120 HPH-C18 column (2.1 × 50 mm; 4 µm) and a Poroshell HPH-C18 (2.1 × 10 mm; 4 µm) guard column (Agilent, USA) were used. The column temperature was set at 50 °C, the autosampler temperature at 10 °C, and with an injection volume of 6 µL. Separation was performed using a gradient between mobile phases A (ammonium acetate 10 mmol·L-1 ) and B (acetonitrile). The gradient was: 0 min, 95% A, 5% B; 0.86 min, 95% A, 5% B; 5.50 min, 82% A, 18% B; 5.83 min, 4% A, 96% B; 6.50 min, 4% A, 96% B; 7.33 min, 95% A, 5% B; 12 min, 95% A, 5% B; with a flow rate of 500 µL·min-1 . Positive ESI was applied under a desolvatation gas flow of 500 L·h-1 , capillary voltage of 4500 V, cone voltage of 41 V, and collision energy between 15 and 17 eV. The quantification values of total NNK were calculated based on the peak area ratio between NNK and the internal standard.

[0255] Matrix bound NNK values were obtained from the difference of total NNK and soluble NNK.

[0256] TSNA levels in the aerosol emission generated by heating the products were also determined by LC-MS / MS, as discussed in relation to NNK specifically. The only difference related to the sample preparation. Samples were heated in an external heating non-combustible aerosol-provision device using the HCI (Health Canada Intense) smoking regimen, and subjected to 8 puffs / stick (3 sticks per replicate and 3 replicates / sample). The particulate phase of emission was collected on Cambridge filter pads, extracted and quantified based on LC-MS / MS (as described, based on Lang, G., and Vuarnoz, A. (2015)).ResultsRich Tobacco Blend (RTB)

[0257] The amounts of TSNAs before (left-hand bars) and after (right-hand bars) heating reconstituted tobacco materials comprising RTB and a binder, or binder combination, are shown in Figures 1 and 2.

[0258] The inventors found that RTB products using acacia as a binder had the highest amounts of retained NAB, NAT and NNN post-heating. No significant differences in the amount of retained free NNK post-heating were observed.

[0259] For all of the reconstituted tobacco materials comprising RTB, there was a significant shift in the proportion of matrix-bound to free NNK after heating the products (Figure 2). The amount of matrix-bound NNK in the product was between 71-73% before heating and between 7-10% after heating. In contrast, the amount of free NNK was between 27-29% before heating and between 90-93% after heating. This shift from matrix-bound to free NNK indicates the release of NNK during the heating process.

[0260] The amounts of TSNAs in the aerosol emissions from the RTB products are shown in Figure 3. Significantly the lowest amounts of NAB, NAT, NNN and NNK in the aerosol emission were found in RTB reconstituted tobacco materials comprising acacia as the binder.Light Tobacco Blend (LTB)

[0261] The amounts of TSNAs before (left-hand bars) and after (right-hand bars) heating reconstituted tobacco materials comprising LTB and a binder, or binder combination, are shown in Figures 4 and 5.

[0262] The inventors found that LTB products using acacia or CMC as a binder had the highest amounts of retained TSNAs (NAB, NAT, NNN and NNK) post-heating.

[0263] The reconstituted tobacco materials comprising LTB showed a significant shift from matrix-bound to free NNK after heating the product, which was observed for all binder or binder combinations used (Figure 5). Compared to RTB products, the ratio of free NNK to matrix-bound NNK in the LTB products was higher before heating. The amount of matrix-bound NNK was between 39-41% before heating and between 3-7% after heating. In contrast, the amount of free NNK was between 59-61% before heating and between 93-97% after heating.

[0264] The amounts of TSNAs in the aerosol emissions from the LTB products are shown in Figure 6.Conclusions

[0265] Surprisingly, the effect of including different binders in reconstituted tobacco materials on the TSNA content of aerosols generated upon heating was found to vary significantly depending on the nature of the tobacco blend. In particular, the use of a binder, such as acacia gum, was found to significantly reduce the TSNA content of aerosol emissions in RTB products, but this effect was not seen with the LTB.

[0266] Acacia gum provides the highest retention potential in the RTB material, and the lowest TSNA content in the aerosol emission from the RTB, but this effect was not seen in the LTB products.Retention of TSNAs after heating

[0267] The Retained (%) of TSNAs in reconstituted tobacco materials comprising a RTB and comprising a LTB, was calculated using Equation 1. The results are shown in Figure 7.

[0268] The inventors generally observed a much higher retention of TSNAs for the RTB products when acacia or CMC was used as the binder, relative to the LTB material. The measured level of retained TSNAs is a combination of the separate processes of the thermogeneration of TSNAs and the retention of TSNAs within the material. The inventors have found that in the LTB material the effect of the binder was essentially entirely through retention of TSNAs rather than as a result of the inhibition of thermogeneration. In contrast, in the RTB material the Retained (%) of TSNAs was found to be increased due to the additional significant inhibition of thermogeneration.Example 2Tobacco preparation

[0269] Products comprising reconstituted tobacco extruded sheets were prepared using a method as described in Example 1, comprising ground tobacco, cellulose fibre, glycerol, a pH modifying agent, and one or more binders, in the proportions shown in Table 2 (values are % by mass). Table 2Reconstituted Tobacco Material No.123456789101112131415161718BlendLTB555555---5555--5555--55-55-RTB---555555--5555--5555-55-55Cellulose fibre252720252720202220222022202215151515Glycerol151515151515151515151515151515151515BinderCMC5--5--5-5-5-5-----Xanthan-3--3--3-3-3-3----Acacia--10--10--------10101010pH ModifierCalcium Carbonate------5555----55--Sodium Citrate----------5555--55 Smoking Regime and Analysis

[0270] Tobacco product consumables in a demi slim format, each comprising aerosol generating material comprising one of the reconstituted tobacco materials detailed in Table 2, were produced. Each reconstituted tobacco, in the form of an extruded sheet, was chopped (cut rag format) and prepared into a king size demi-slim format consumable. The consumables were then heated in a Glo Hyper device, and the TSNAs were measured as described in relation to Example 1.ResultsRich Tobacco Blend (RTB)

[0271] The amounts of TSNAs before (left-hand bars) and after (right-hand bars) heating reconstituted tobacco materials comprising RTB and a binder (acacia, CMC or xantham) are shown in Figure 8.

[0272] As previously shown in Example 1, the inventors found that materials comprising acacia gum as the binder had the highest amounts of retained TSNAs (NAB free, NAT free, NNN free and NNK free) post-heating.

[0273] The inventors then tested the effects of the additional inclusion of a pH modifier (carbonate or citrate) on the TSNA levels pre- and post-heating. The results are shown in Figure 9.

[0274] The addition of a pH modifier had the effect of reducing the amounts of free NAB, NAT and NNN in the material after heating. The effect of reducing the amount of TSNAs was observed for all of the pH modifiers tested by the inventors, and was generally most significant for citrate. The pH modifier did not have a significant effect on the amount of retained free NNK in the product after heating.

[0275] The same trend was observed when using any one of acacia, CMC or xanthan as a binder, as shown in Figure 10.

[0276] Without being bound by any particular theory, the pH modifier is thought to reduce the level of TSNAs in the material post-heating by reducing the generation of TSNAs when the material is heated, rather than by reducing the retention of the TSNAs.

[0277] This understanding is supported by the results shown in Figure 11, which shows the amounts of TSNAs in the aerosol emissions. The addition of citrate as a pH modifier further reduced the amounts of NAB, NNN, and NAT in the emission when compared to using the binder alone. In some cases, the amount of TSNAs was reduced by 30-40%. The greatest reduction of NAB, NNN and NAT was found when using acacia as the binder.

[0278] These results, and the fact that the levels of TSNA in the aerosol emissions are not increased in the presence of the pH modifiers, suggests that the pH modifiers reduce the thermogeneration of the TSNA in the RTB reconstituted tobacco materials when heated.

[0279] Overall, the combination of using acacia as a binder and citrate as a pH modifier generally resulted in the lowest amounts of TSNAs in the aerosol emissions of the RTB reconstituted tobacco materials.

[0280] Figure 12 shows a shift from matrix-bound to free NNK after heating.Light Tobacco Blend (LTB)

[0281] The amounts of TSNAs before (left-hand bars) and after (right-hand bars) heating reconstituted tobacco materials comprising LTB and a binder (acacia, CMC or xanthan) are shown in Figure 13.

[0282] The addition of a pH modifier did not significantly alter the amounts of NAT, NNN, or free NNK in the products post-heating (Figures 14 and 15).

[0283] The amounts of TSNAs in the emission are shown in Figure 16. The inventors found that materials comprising acacia as a binder had the lowest amounts of TSNAs (NAB, NNN, NAT and NNK) in the emission when compared to CMC or xanthan.

[0284] In contrast to the effects on reconstituted tobacco materials comprising RTB, the addition of a pH modifier did not significantly further reduce the TSNA levels in the aerosol emissions compared to the use of a binder alone.

[0285] Figure 16 shows a significant shift from matrix-bound to free NNK post-heating for all binders, or binder and pH modifier combinations, used.Conclusions

[0286] As in Example 1, the effect of including different additives (binders, pH modifiers) in reconstituted tobacco materials on the TSNA content of aerosols generated upon heating was found to vary significantly depending on the nature of the tobacco blend.

[0287] In particular, with a RTB, the use of a pH modifier, and in particular citrate, was found to provide a synergistic effect in combination with the use of a binder, such as acacia gum, in reducing the TSNA content of the aerosol emissions.

[0288] Surprisingly, however, the same effect was not seen with a LTB. With a LTB, the TSNA levels in the aerosol emissions were greater with a binder and pH modifier than with binder alone (Figure 17).

[0289] The balance between NNK matrix-bound and NNK free indicates that heating causes both a release from matrix-bound to free NNK and thermogeneration free NNK free. The findings in Examples 1 and 2 suggest that pH modifiers reduce the thermogeneration of TSNA upon heating of reconstituted tobacco materials, whereas binders increase the retention of the TSNAs in the material.

[0290] The most significant effects are seen for NAB, NAT, and NNN. For NNK, the reductions observed in the aerosol emissions were lower, suggesting that additional factors may be involved in the regulation of the production and release of this compound.

[0291] The specific effects seen are also different with different tobacco blends. When the tobacco blend was a RTB, the use of a pH modifier, and in particular citrate, was found to provide a synergistic effect in combination with the use of a binder, such as acacia gum, in reducing the TSNA content of the aerosol emissions.

[0292] Overall, these results indicate that a combination of a binder and a pH modifier, and in particular, a combination of acacia gum and citrate, provide a synergistic effect and may be used to reduce the TSNA content of aerosol emissions generated upon heating reconstituted tobacco materials comprising, RTB but not LTB.Nicotine

[0293] The distribution of the differently protonated forms of nicotine in the reconstituted tobacco materials pre- and post-heating, and in the aerosol emissions of the materials upon heating, are shown in Figures 18 (RTB) and 19 (LTB).

[0294] The proportion of nicotine in the deprotonated state (i.e. [Nic]; top shaded section of each bar) is significantly increased in materials comprising a binder and pH modifier, and in particular, acacia gum and citrate in materials comprising a RTB (Figure 18).

[0295] In contrast, no significant effects on the [Nic] was seen with the LTB.Example 3Tobacco preparation

[0296] The inventors prepared tobacco lamina material comprising RTB. The tobacco lamina material was coated in a composition comprising a binder (acacia gum) and a pH modifier (sodium citrate). The coating process was performed by a method comprising preparing separate solutions of sodium citrate and acacia gum in water and applying as a spray to tobacco threshed leaf. The compositions of the tobacco lamina products are detailed in Table 3. Table 31234RTB only (Control)RTBRTBRTB+ 5% Citrate+ 10% Acacia+ 10% Acacia+ 5% CitrateRTB (%)100959085Cellulose fibre (%)----Glycerol (%)----Acacia Gum (%)--1010Sodium Citrate (%)-5-5 Smoking Regime and Analysis

[0297] Each tobacco lamina material was chopped (cut rag format) and prepared into a king size demi-slim format consumable. The consumables were then heated in a Glo Hyper device, and the TSNAs were measured as described in relation to Example 1.

[0298] The levels of TSNA (NAB, NAT, NNN and NNK free and NNK matrix-bound) in the products were analysed and determined by LC-MS / MS, as described in Example 1. The total particulate matter (TPM) content and levels of Hoffmann analytes was also analysed.

[0299] Three replicate measurements were carried out with three consumables per replicate.Results

[0300] The addition of a binder and / or pH modifier to the tobacco lamina product did not significantly alter the total particulate matter content, as shown in Figure 20.

[0301] The amounts of TSNAs (NAB, NAT, NNN and NNK free) in the tobacco lamina product were determined before (left-hand bars) and after (right-hand bars) heating, and the results are shown in Figure 21.

[0302] Figure 22 shows the amounts of TSNAs in the aerosol emissions generated when the lamina material is heated. The amounts of NNN, NAT and NNK in the aerosol emissions were reduced in the products comprising a combination of acacia and citrate by an amount significantly greater than the reductions seen with binder or pH modifier alone.

[0303] Hoffmann analytes in emissions are shown in Table 4. Table 41234Component (µg / stick)RTB only (Control)RTBRTBRTB+ 5% Citrate+ 10% Acacia+ 10% Acacia+ 5% Citrate1,3-Butadiene1.601.601.601.60Acetaldehyde77.2362.5076.5750.47Acetone21.7023.2019.8020.23Acrolein0.801.201.200.80Acrylonitrile1.101.101.101.10Benzene1.701.701.701.70Benzo-a-pyrene1.501.001.001.00Butyraldehyde4.404.404.404.40Crotonaldehyde1.301.302.671.30Formaldehyde1.301.301.301.30Isoprene13.3013.3013.3013.30Methyl ethyl ketone6.606.606.603.20Nicotine2.682.582.282.18Propionaldehyde11.008.4715.539.83Pyridine6.175.536.375.80Quinoline0.060.060.060.06Styrene0.500.500.500.50Toluene1.701.701.701.70

[0304] The levels of the Hoffmann analytes in the aerosol emissions were not significantly affected by the inclusion of acacia gum and / or citrate in the aerosol generating material.

[0305] These results indicate that a combination of binder and pH modifier, and in particular, acacia gum and citrate, may advantageously be used to reduce the levels of TSNA present in the aerosol emissions generated when the materials are heated.

[0306] The inventors have found that effect of the addition of a binder and a pH modifier is specific to TSNAs and does not affect the levels of other compounds emitted from the tobacco blend. Advantageously, the inventors have found that the addition of a binder and a pH modifier does not significantly reduce the levels of odour and flavour-providing compounds, or odour activity values (OAVs), of the emitted aerosol. The use of a binder and pH modifying agent, therefore, in tobacco blends comprising a high level of TSNAs, provides an advantageous tool for reducing the level of TSNAs in the aerosol without affecting the flavour or aroma.

[0307] Moreover, this effect is observed for tobacco blends having a total content of NAB, NAT, NNK, and NNN of greater than 650 ppb (w / w), and is independent of the form of the aerosol generating material comprising the tobacco (lamina, reconstituted material, etc.).Numbered Clauses

[0308] The following clauses form part of the description and not the claims. They are provided to assist with the understanding of the invention, and do not define the scope of the claimed subject matter. 1. An aerosol generating material for use in an article for use with a non-combustible aerosol-provision device, the aerosol generating material comprising tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w). 2. An aerosol generating material of clause 1, wherein the tobacco material comprises a NNK content greater than 120 parts per billion (w / w). 3. An aerosol generating material of clause 1 or 2, wherein the tobacco material comprises a NNN content greater than 120 parts per billion (w / w). 4. An aerosol generating material of any of the preceding clauses, wherein the aerosol generating material comprises air cured tobacco. 5. An aerosol generating material of any of the preceding clauses, wherein the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated. 6. An aerosol generating material of any of the preceding clauses, wherein the binder comprises acacia gum, xanthan gum, and / or carboxymethyl cellulose (CMC). 7. An aerosol generating material of any of the preceding clauses, wherein the binder comprises acacia gum. 8. An aerosol generating material of any of the preceding clauses, wherein the binder is present in a total amount of 1-20% by mass of the aerosol generating material. 9. An aerosol generating material of any of the preceding clauses, wherein the binder comprises acacia gum in an amount of greater than 11% by mass of the aerosol generating material. 10. An aerosol generating material of any of the preceding clauses, wherein the pH modifying agent comprises a salt of citric acid. 11. An aerosol generating material of clause 10, wherein the pH modifying agent comprises sodium citrate. 12. An aerosol generating material of any of the preceding clauses, wherein the pH modifying agent comprises a salt of carbonic acid. 13. An aerosol generating material of any of the preceding clauses, wherein the pH modifying agent is present in a total amount of 2-10% by mass of the aerosol generating material. 14. An aerosol generating material of any of the preceding clauses, wherein the aerosol generating material further comprises an aerosol forming material in an amount of 5-25% by weight of the aerosol generating material. 15. An aerosol generating material of any of the preceding clauses, wherein the tobacco material comprises reconstituted tobacco material. 16. An aerosol generating material of any of the preceding clauses, wherein the reconstituted tobacco material is a dried dough or slurry comprising the pH modifying agent, the binder, and the tobacco material. 17. An aerosol generating material of any of the preceding clauses, wherein the tobacco material comprises tobacco lamina. 18. An aerosol generating material of any of the preceding clauses, wherein the binder and / or the pH modifying agent are present in a coating on the surface of the aerosol generating material. 19. A method of producing a reconstituted tobacco material for use in or as an aerosol generating material of clauses 1-16, the method comprising: (a) producing a dough or slurry comprising tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w); and (b) drying the dough or slurry to produce the reconstituted tobacco material. 20. A method of producing a tobacco material for use in or as an aerosol generating material of clauses 1-14 or 17, the method comprising applying a coating to tobacco material, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w), and wherein the coating comprises a binder and a pH modifying agent. 21. An aerosol generating material produced, obtained, or obtainable by the method of clause 19 or 20. 22. A component for a delivery system, wherein the component comprises aerosol generating material of clauses 1-18, or produced, obtained, or obtainable by the method of clause 19 or 20. 23. A system comprising an aerosol-generating material of clauses 1-18 or 21, and a device arranged to heat the aerosol-generating material and generate an aerosol from the aerosol-generating material. 24. The use of the combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco material to reduce the TSNA content, but not the aroma content, of the aerosol generated when the aerosol generating material is heated, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w). 25. A method of reducing the level of TSNA, without reducing the aroma, of an aerosol generated when a tobacco-containing aerosol generating material comprising a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w) is heated, the method comprising including a binder and a pH modifying agent in or on the aerosol generating material.

Claims

1. An aerosol generating material for use in an article for use with a non-combustible aerosol-provision device, the aerosol generating material comprising tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w).

2. An aerosol generating material as claimed in claim 1, wherein the tobacco material comprises: (i) a NNK content greater than 120 parts per billion (w / w); and / or (ii) a NNN content greater than 120 parts per billion (w / w).

3. An aerosol generating material as claimed in claim 1 or 2, wherein the aerosol generating material comprises air cured tobacco.

4. An aerosol generating material as claimed in any of the preceding claims, wherein the TSNA content of the aerosol generated when an aerosol generating material comprising tobacco comprising a total content of NNN, NNK, NAB, and NAT of greater than 650 parts per billion (w / w), a binder, and a pH modifier, is heated, is lower than the TSNA content of an aerosol generated when an equivalent aerosol generating material, that does not comprise a binder and a pH modifying agent, is equivalently heated.

5. An aerosol generating material as claimed in any of the preceding claims, wherein the binder comprises acacia gum, xanthan gum, and / or carboxymethyl cellulose (CMC).

6. An aerosol generating material as claimed in any of the preceding claims, wherein the binder comprises acacia gum in an amount of greater than 11% by mass of the aerosol generating material.

7. An aerosol generating material as claimed in any of the preceding claims, wherein the pH modifying agent comprises: (i) a salt of citric acid; and / or (ii) a salt of carbonic acid.

8. An aerosol generating material as claimed in any of the preceding claims, wherein the pH modifying agent comprises sodium citrate in a total amount of 2-10% by mass of the aerosol generating material.

9. An aerosol generating material as claimed in any of the preceding claims, wherein the aerosol generating material further comprises an aerosol forming material in an amount of 5-25% by weight of the aerosol generating material.

10. An aerosol generating material as claimed in any of the preceding claims, wherein the tobacco material comprises: (i) reconstituted tobacco material that is a dried dough or slurry comprising the pH modifying agent, the binder, and the tobacco material; or (ii) tobacco lamina, wherein the binder and / or the pH modifying agent are present in a coating on the surface of the aerosol generating material.

11. A method of producing a reconstituted tobacco material for use in or as an aerosol generating material as claimed in any of claims 1-9, the method comprising: (a) producing a dough or slurry comprising tobacco material, a binder, and a pH modifying agent, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w); and (b) drying the dough or slurry to produce the reconstituted tobacco material.

12. A method of producing a tobacco material for use in or as an aerosol generating material as claimed in any of claims 1-9, the method comprising applying a coating to tobacco material, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w), and wherein the coating comprises a binder and a pH modifying agent.

13. An aerosol generating material produced, obtained, or obtainable by the method of claim 11 or 12.

14. A system comprising an aerosol-generating material as claimed in any of claims 1-10 or 13, and a device arranged to heat the aerosol-generating material and generate an aerosol from the aerosol-generating material.

15. The use of the combination of a binder and a pH modifying agent in an aerosol generating material comprising tobacco material to reduce the TSNA content, but not the aroma content, of the aerosol generated when the aerosol generating material is heated, wherein the tobacco material comprises a total content of N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) of greater than 650 parts per billion (w / w).

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