Aerosol-generating article comprising a solid aerosol-generating substrate and a susceptor - Patent Application 20070233633

Abstract

An aerosol-generating article (10) for use in an aerosol-generating system, the aerosol-generating article comprising: a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that (i) contain no non-carboxyl alkyl hydroxyl groups and do not contain ketone groups, or (ii) have a pKa in water of 3.5 or less at 25° C., or (iii) contain no non-carboxyl alkyl hydroxyl groups, do not contain ketone groups, and have a pKa in water of 3.5 or less at 25° C.; and a susceptor (44) in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 weight percent, a total aerosol former content of at least 45 weight percent, and a total carboxylic acid content of at least 0.5 weight percent. The aerosol-generating system comprises the aerosol-generating article and an electrically powered aerosol generating device including an inductor configured to heat the solid aerosol-generating substrate of the aerosol-generating article.

Description

[Technical field]

[0001] The present invention relates to an aerosol-generating article comprising a solid aerosol-generating substrate and a susceptor. The present invention also relates to an aerosol-generating system comprising the aerosol-generating article and an electrically-operated aerosol generating device configured to heat the aerosol-generating article. [Background technology]

[0002] Aerosol-generating articles in which an aerosol-generating substrate, such as a tobacco-containing material, is heated to form smoke rather than combusted to form an aerosol are known in the art. One purpose of such "heat-not-burn" aerosol-generating articles is to reduce the known harmful smoke constituents of the type produced by the combustion and pyrolytic decomposition of tobacco in conventional cigarettes.

[0003] Typically, in heated aerosol-generating articles, the aerosol is generated by the transfer of heat from a heat source to a physically separate aerosol-generating substrate. In use, volatile compounds are released from the aerosol-generating substrate by the transfer of heat from the heat source to the aerosol-generating substrate and are entrained in the air drawn through the aerosol-generating article. As the released compounds cool, they condense to form an aerosol that is inhaled by the user.

[0004] A number of handheld aerosol generating devices configured to heat an aerosol-generating substrate of a heated aerosol-generating article are known in the art. Such devices include electrically operated aerosol generating devices in which an aerosol is generated by heat transfer from one or more electric heating elements of the aerosol generating device to the aerosol-generating substrate of the heated aerosol-generating article. Known handheld electrically operated aerosol generating devices typically comprise a battery, control electronics, and one or more electric heating elements for heating the aerosol-generating substrate of the heated aerosol-generating article that are specifically designed for use with the aerosol generating device.

[0005] Some known electrically powered aerosol generating devices include an internal heating element configured to be inserted into the aerosol-generating substrate of a heated aerosol-generating article. For example, 2013 / 098410A2 discloses an aerosol generating system comprising an aerosol-generating article and an electrically powered aerosol generating device including a heating element in the form of a blade that is inserted into the aerosol-generating substrate of the aerosol-generating article.

[0006] Other known electrically powered aerosol generating devices include one or more external heating elements. For example, WO2020 / 115151A1 discloses an aerosol generating system including an aerosol-generating article and an electrically powered aerosol generating device that includes an external heating element surrounding the periphery of the aerosol-generating article.

[0007] Electrically operated aerosol generating devices are also known in the art, including an inductor configured to inductively heat an aerosol-generating substrate of a heated aerosol-generating article. For example, WO2015 / 176898A1 discloses an aerosol generating system including an aerosol-generating article, including an elongated susceptor in thermal contact with the aerosol-generating substrate, and an electrically operated aerosol generating device having an inductor for heating the aerosol-generating substrate. In use, a fluctuating or alternating electromagnetic field generated by the inductor induces eddy currents in the susceptor, which cause the susceptor to heat as a result of one or both of resistive losses (Joule heating) and hysteretic losses (if the susceptor is magnetic). The heat generated in the susceptor is transferred to the aerosol-generating substrate by conduction.

[0008] Solid aerosol-generating substrates for use in heated aerosol-generating articles typically include one or more aerosol formers, such as glycerin and propylene glycol. It is known to include flavorants in solid aerosol-generating substrates for use in heated aerosol-generating articles. It is also known to include acids in solid aerosol-generating substrates for use in heated aerosol-generating articles.

[0009] The inclusion of an acid in a solid aerosol-generating substrate for use in a heated aerosol-generating article may advantageously enable the generation of inhalable aerosols with improved sensory properties. The inclusion of an acid in a solid aerosol-generating substrate containing nicotine for use in a heated aerosol-generating article may advantageously enable the generation of inhalable aerosols that provide improved nicotine satisfaction to the user.

[0010] However, the inclusion of an acid in a solid aerosol-generating substrate for use in a heated aerosol-generating article may adversely affect the stability of the solid aerosol-generating substrate during storage of the heated aerosol-generating article. For example, the inclusion of an acid in a solid aerosol-generating substrate containing one or more flavourants for use in a heated aerosol-generating article may disadvantageously reduce the flavour stability of the solid aerosol-generating substrate during storage of the heated aerosol-generating article.

[0011] The inclusion of an acid in a solid aerosol-generating substrate for use with a heated aerosol-generating article may lead to the undesirable corrosion of components of the aerosol-generating system that includes the heated aerosol-generating article. For example, the inclusion of an acid in a solid aerosol-generating substrate for use with a heated aerosol-generating article may lead to the undesirable corrosion of metal components of the aerosol-generating system that includes the heated aerosol-generating article. In particular, the inclusion of an acid in a solid aerosol-generating substrate for use with a heated aerosol-generating article may lead to the undesirable corrosion of non-precious metal components, such as chromium-containing components, copper-containing components, nickel-containing components, tin-containing components, and zinc-containing components, of the aerosol-generating system that includes the heated aerosol-generating article.

[0012] The inclusion of an acid in a solid aerosol-generating substrate for use in a heated aerosol-generating article may undesirably lead to corrosion of components of the heated aerosol-generating article. For example, when a heated aerosol-generating article for use in an aerosol-generating system comprises a solid aerosol-generating substrate and a susceptor, the inclusion of an acid in the solid aerosol-generating substrate may undesirably lead to corrosion of the susceptor. In particular, when a heated aerosol-generating article for use in an aerosol-generating system comprises a solid aerosol-generating substrate and a susceptor in direct contact with the solid aerosol-generating substrate, the inclusion of an acid in the solid aerosol-generating substrate may undesirably lead to corrosion of the susceptor.

[0013] Aerosol formers such as glycerin and propylene glycol are hygroscopic, and the inclusion of high aerosol former contents in solid aerosol-generating substrates for use in heated aerosol-generating articles can disadvantageously exacerbate corrosion of components of the aerosol generation system that includes the heated aerosol-generating article.

[0014] Cellulosic agents are hydrophilic. The inclusion of high cellulosic agent contents in solid aerosol-generating substrates for use in heated aerosol-generating articles can disadvantageously exacerbate corrosion of components of the aerosol generation system that includes the heated aerosol-generating article.

[0015] Aerosol-generating articles comprising solid aerosol-generating substrates that exhibit improved stability compared to known aerosol-generating articles are desirable.

[0016] In particular, it would be desirable to provide an aerosol-generating article comprising a solid aerosol-generating substrate and a susceptor that exhibits improved stability compared to known aerosol-generating articles. Summary of the Invention

[0017] The present invention relates to an aerosol-generating article for use in an aerosol-generating system. The aerosol-generating article may comprise a solid aerosol-generating substrate. The aerosol-generating article may comprise a susceptor. The susceptor may be in direct contact with the solid aerosol-generating substrate. The solid aerosol-generating substrate may comprise nicotine. The solid aerosol-generating substrate may comprise one or more aerosol formers. The solid aerosol-generating substrate may comprise one or more cellulosic agents. The solid aerosol-generating substrate may comprise one or more carboxylic acids. The one or more carboxylic acids may be free of non-carboxyl alkyl hydroxyl groups. The one or more carboxylic acids may be free of ketone groups. The one or more carboxylic acids may have a pKa in water of 3.5 or less at 25° C. The solid aerosol-generating substrate may have a total aerosol former content of 45 weight percent or more. The solid aerosol-generating substrate may have a total cellulosic agent content of 35 weight percent or more. The solid aerosol-generating substrate may have a total carboxylic acid content of 0.5 weight percent or more. The solid aerosol-generating substrate may be free of iota-carrageenan or kappa-carrageenan.The solid aerosol-generating substrate may remain solid when heated to a temperature of between 180 degrees Celsius and 350 degrees Celsius.

[0018] The present invention also relates to an aerosol generating system. The aerosol generating system may comprise an aerosol generating article. The aerosol generating article may comprise a solid aerosol generating substrate. The aerosol generating article may comprise a susceptor. The susceptor may be in direct contact with the solid aerosol generating substrate. The solid aerosol generating substrate may comprise nicotine. The solid aerosol generating substrate may comprise one or more aerosol formers. The solid aerosol generating substrate may comprise one or more cellulosic agents. The solid aerosol generating substrate may comprise one or more carboxylic acids. The one or more carboxylic acids may be free of non-carboxyl alkyl hydroxyl groups. The one or more carboxylic acids may be free of ketone groups. The one or more carboxylic acids may have a pKa in water of 3.5 or less at 25° C. The solid aerosol generating substrate may have a total aerosol former content of 45 weight percent or more. The solid aerosol generating substrate may have a total cellulosic agent content of 35 weight percent or more. The solid aerosol generating substrate may have a total carboxylic acid content of 0.5 weight percent or more. The solid aerosol-generating substrate may be free of iota-carrageenan or kappa-carrageenan. The solid aerosol-generating substrate may remain solid when heated to a temperature between 180 degrees Celsius and 350 degrees Celsius. The aerosol-generating system may comprise an electrically operated aerosol-generating device. The electrically operated aerosol-generating device may comprise an inductor. The inductor may be configured to heat the solid aerosol-generating substrate of the aerosol-generating article.

[0019] According to a first aspect of the present invention, there is provided an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids that (i) contain no non-carboxyl alkyl hydroxyl groups and do not contain ketone groups, or (ii) have a pKa in water of 3.5 or less at 25° C., or (iii) contain no non-carboxyl alkyl hydroxyl groups, do not contain ketone groups and have a pKa in water of 3.5 or less at 25° C., and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate has a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0020] According to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 weight percent or more, a total cellulosic agent content of at least 35 weight percent, and a total carboxylic acid content of at least 0.5 weight percent.

[0021] According to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C.; and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0022] According to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups, do not contain ketone groups and have a pKa in water of 3.5 or less at 25° C.; and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate has a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight and a total carboxylic acid content of at least 0.5 percent by weight.

[0023] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, undecanoic acid and C1 to C10 saturated alkyl monocarboxylic acids, and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate has a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0024] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid and undecanoic acid, and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate has a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0025] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid and undecanoic acid, and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate has a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0026] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, maleic acid and malic acid, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight and a total carboxylic acid content of at least 0.5 percent by weight.

[0027] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid and maleic acid, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight and a total carboxylic acid content of at least 0.5 percent by weight.

[0028] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from fumaric acid, maleic acid and malic acid, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0029] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids selected from fumaric acid and maleic acid, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0030] In particular, according to a first aspect of the present invention there is provided an aerosol-generating article for use in an aerosol generation system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and fumaric acid, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total aerosol former content of 45 percent by weight or more, a total cellulosic agent content of at least 35 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0031] There is also provided, according to a first aspect of the present invention, an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups, and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate does not contain iota-carrageenan or kappa-carrageenan.

[0032] There is also provided according to a first aspect of the present invention an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate does not comprise iota-carrageenan or kappa-carrageenan.

[0033] There is also provided according to a first aspect of the present invention an aerosol-generating article for use in an aerosol-generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups, do not contain ketone groups and have a pKa in water of 3.5 or less at 25° C.; and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate does not contain iota-carrageenan or kappa-carrageenan.

[0034] There is also provided according to a first aspect of the present invention an aerosol-generating article for use in an aerosol generating system comprising a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups, and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate remains solid when heated to a temperature of between 180 degrees Celsius and 350 degrees Celsius.

[0035] There is also provided according to a first aspect of the present invention an aerosol-generating article for use in an aerosol generating system, comprising: a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and a carboxylic acid having a pKa in water of 3.5 or less at 25°C; and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate remains solid when heated to a temperature of between 180°C and 350°C.

[0036] Also according to a first aspect of the present invention, there is provided an aerosol-generating article for use in an aerosol generating system, comprising: a solid aerosol-generating substrate comprising nicotine, one or more aerosol formers, one or more cellulosic agents, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups, do not contain ketone groups and have a pKa in water of 3.5 or less at 25°C; and a susceptor in direct contact with the solid aerosol-generating substrate, wherein the solid aerosol-generating substrate remains solid when heated to a temperature of between 180°C and 350°C.

[0037] According to a second aspect of the present invention, there is provided an aerosol generating system comprising an aerosol-generating article according to the first aspect of the present invention and an electrically operated aerosol generating device including an inductor configured to heat a solid aerosol-generating substrate of the aerosol-generating article.

[0038] It has been surprisingly found that by including one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention, the stability of the solid aerosol-generating substrate during storage of the aerosol-generating article according to the first aspect of the invention can be advantageously improved. In particular, it has been surprisingly found that by including one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention, the stability of nicotine in the solid aerosol-generating substrate during storage of the aerosol-generating article according to the first aspect of the invention can be advantageously improved.

[0039] It has been surprisingly found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups and that do not contain ketone groups, corrosion of the components of the aerosol-generating article according to the first aspect of the invention and the components of the aerosol-generating system according to the second aspect of the invention can be advantageously inhibited. In particular, it has been surprisingly found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups and that do not contain ketone groups, corrosion of the metal components of the aerosol-generating article according to the first aspect of the invention and the metal components of the aerosol-generating system according to the second aspect of the invention can be advantageously inhibited.

[0040] It has been found that by including one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups and that do not contain ketone groups in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention, corrosion of the susceptor of the aerosol-generating article according to the first aspect of the invention can be advantageously inhibited. In particular, it has been found that by including one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups and that do not contain ketone groups in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention, corrosion of the susceptor of the aerosol-generating article according to the first aspect of the invention can be advantageously inhibited during storage of the aerosol-generating article according to the first aspect of the invention.

[0041] Surprisingly, it has been found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., the stability of the solid aerosol-generating substrate during storage of the aerosol-generating article according to the first aspect of the invention may advantageously be improved. In particular, it has been found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., the stability of nicotine in the solid aerosol-generating substrate during storage of the aerosol-generating article according to the first aspect of the invention may advantageously be improved.

[0042] It has surprisingly been found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., corrosion of components of the aerosol-generating article according to the first aspect of the invention and components of the aerosol-generating system according to the second aspect of the invention can be advantageously inhibited. In particular, it has surprisingly been found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., corrosion of metal components of the aerosol-generating article according to the first aspect of the invention and metal components of the aerosol-generating system according to the second aspect of the invention can be advantageously inhibited.

[0043] It has been found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., corrosion of the susceptor of the aerosol-generating article according to the first aspect of the invention can be advantageously inhibited. In particular, it has been found that by including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., corrosion of the susceptor of the aerosol-generating article according to the first aspect of the invention can be advantageously inhibited during storage of the aerosol-generating article according to the first aspect of the invention.

[0044] Without wishing to be bound by theory, it is believed that carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups, when included in a solid aerosol-generating substrate, are less likely to oxidize other components of the aerosol-generating article according to the first aspect of the invention and components of the aerosol-generating system according to the second aspect of the invention than carboxylic acids that contain non-carboxyl alkyl hydroxyl groups. Without wishing to be bound by theory, it is believed that carboxylic acids that do not contain ketone groups, when included in a solid aerosol-generating substrate, are less likely to oxidize other components of the aerosol-generating article according to the first aspect of the invention and components of the aerosol-generating system according to the second aspect of the invention than carboxylic acids that contain ketone groups. It is believed that the inclusion of one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups and that do not contain ketone groups in the solid aerosol-generating substrate thereby inhibits corrosion of components of the aerosol-generating article according to the first aspect of the invention and components of the aerosol-generating system according to the second aspect of the invention.

[0045] Without wishing to be bound by theory, it is believed that carboxylic acids having a pKa in water of 3.5 or less at 25°, when included in the solid aerosol-generating substrate, are less likely to oxidize other components of the aerosol-generating article according to the first aspect of the invention and components of the aerosol-generating system according to the second aspect of the invention than carboxylic acids having a pKa in water of greater than 3.5 at 25° C. It is believed that the inclusion of one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C. in the solid aerosol-generating substrate thereby inhibits corrosion of components of the aerosol-generating article according to the first aspect of the invention and components of the aerosol-generating system according to the second aspect of the invention.

[0046] As used herein in connection with the present invention, the term "aerosol-generating article" is used to describe an article that includes an aerosol-generating substrate that is heated to generate and deliver an inhalable aerosol to a user.

[0047] As used herein in connection with the present invention, the term "aerosol" is used to describe a dispersion of solid particles, or liquid droplets, or a combination of solid particles and liquid droplets, in a gas. Aerosols can be visible or invisible. Aerosols may include vapors of substances that are normally liquids or solids at room temperature, as well as solid particles, or liquid droplets, or a combination of solid particles and liquid droplets.

[0048] As used herein in connection with the present invention, the term "aerosol-generating substrate" is used to describe a substrate that includes an aerosol-generating material capable of releasing a volatile compound that is capable of generating an aerosol upon heating.

[0049] As used herein in connection with the present invention, the term "solid" is used to describe an aerosol-generating substrate that has a stable size and shape and does not flow at 23°C.

[0050] As used herein in connection with the present invention, the term "aerosol-generating device" is used to describe a device that interacts with an aerosol-generating substrate of an aerosol-generating article to generate an aerosol.

[0051] Unless otherwise stated, the weight percentages of the components of the solid aerosol-generating substrate recited herein are based on the dry weight of the solid aerosol-generating substrate.

[0052] The aerosol-generating article has a proximal end at which, in use, the aerosol exits the aerosol-generating article for delivery to a user. The proximal end of the aerosol-generating article may also be referred to as the oral end of the aerosol-generating article. In use, a user inhales the proximal end of the aerosol-generating article to inhale the aerosol generated by the aerosol-generating article.

[0053] The aerosol-generating article has a distal end, the distal end being opposite the proximal end.

[0054] Components of an aerosol-generating article may be described as being upstream or downstream of one another based on their relative location between the proximal end of the aerosol-generating article and the distal end of the aerosol-generating article.

[0055] As used herein in connection with the present invention, the term "longitudinal" is used to describe the direction between the proximal and distal ends of the aerosol-generating article.

[0056] As used herein in connection with the present invention, the term "transverse" is used to describe a direction perpendicular to the longitudinal axis, that is, perpendicular to the direction between the proximal and distal ends of the aerosol-generating article.

[0057] The term "length" as used herein in connection with the present invention is used to describe the maximum dimension of the aerosol-generating article and components of the aerosol-generating article in the longitudinal direction, i.e., in the direction between the proximal and distal ends of the aerosol-generating article.

[0058] The term "width" as used herein in connection with the present invention is used to describe the maximum transverse dimension of the aerosol-generating article and components of the aerosol-generating article, i.e., the maximum dimension of the aerosol-generating article and components of the aerosol-generating article in a direction perpendicular to the direction between the proximal and distal ends of the aerosol-generating article.

[0059] The solid aerosol-generating substrate may remain solid when heated to a temperature of between 180° C. and 350° C. As explained further below, this may advantageously reduce or eliminate crusting of the aerosol-generating article according to the first aspect of the invention.

[0060] For example, the solid aerosol-generating substrate may remain solid when heated to a temperature between 200 degrees Celsius and 320 degrees Celsius, between 220 degrees Celsius and 300 degrees Celsius, or between 240 degrees Celsius and 280 degrees Celsius.

[0061] The solid aerosol-generating substrate may be a solid aerosol-generating film.

[0062] As used herein in connection with the present invention, the term "film" is used to describe a solid aerosol-generating substrate having a thickness that is substantially less than its width or length.

[0063] As used herein in connection with the present invention, the term "thickness" is used to describe the smallest dimension between substantially parallel opposing surfaces of a solid aerosol-generating film.

[0064] The solid aerosol-generating film may have a thickness of 0.05 millimeters or more, 0.1 millimeters or more, 0.2 millimeters or more, or 0.3 millimeters or more.

[0065] The solid aerosol-generating film may have a thickness of 1.2 millimeters or less, 1 millimeter or less, 0.8 millimeters or less, 0.6 millimeters or less, or 0.4 millimeters or less.

[0066] The solid aerosol-generating film may have a thickness of 0.05 millimeters to 1.2 millimeters, 0.05 millimeters to 1 millimeter, 0.05 millimeters to 0.8 millimeters, 0.05 millimeters to 0.6 millimeters, or 0.05 millimeters to 0.4 millimeters.

[0067] The solid aerosol-generating film may have a thickness of 0.1 millimeters to 1.2 millimeters, 0.1 millimeters to 1 millimeter, 0.1 millimeters to 0.8 millimeters, 0.1 millimeters to 0.6 millimeters, or 0.1 millimeters to 0.4 millimeters.

[0068] The solid aerosol-generating film may have a thickness of 0.2 millimeters to 1.2 millimeters, 0.2 millimeters to 1 millimeter, 0.2 millimeters to 0.8 millimeters, 0.2 millimeters to 0.6 millimeters, or 0.2 millimeters to 0.4 millimeters.

[0069] The solid aerosol-generating film may have a thickness of 0.3 millimeters to 1.2 millimeters, 0.3 millimeters to 1 millimeter, 0.3 millimeters to 0.8 millimeters, 0.3 millimeters to 0.6 millimeters, or 0.3 millimeters to 0.4 millimeters.

[0070] The solid aerosol-generating film may have a basis weight of 85 grams per square meter or more, 100 grams per square meter or more, 120 grams per square meter or more, or 140 grams per square meter or more.

[0071] The solid aerosol-generating film may have a basis weight of 300 grams per square meter or less, 280 grams per square meter or less, or 260 grams per square meter or less.

[0072] The solid aerosol-generating film may have a basis weight of 85 grams per square meter to 300 grams per square meter, 85 grams per square meter to 280 grams per square meter, or 85 grams per square meter to 260 grams per square meter.

[0073] The solid aerosol-generating film may have a basis weight of from 100 grams per square meter to 300 grams per square meter, from 100 grams per square meter to 280 grams per square meter, or from 100 grams per square meter to 260 grams per square meter.

[0074] The solid aerosol-generating film may have a basis weight of from 120 grams per square meter to 300 grams per square meter, from 120 grams per square meter to 280 grams per square meter, or from 120 grams per square meter to 260 grams per square meter.

[0075] The solid aerosol-generating film may have a basis weight of 140 grams per square meter to 300 grams per square meter, 140 grams per square meter to 280 grams per square meter, or 140 grams per square meter to 260 grams per square meter.

[0076] The solid aerosol-generating film may be formed by any suitable method, for example, the solid aerosol-generating film may be formed by batch casting, continuous casting, or extrusion.

[0077] The solid aerosol-generating film may be self-supporting, in other words, the properties of the solid aerosol-generating film may be such that it can be separated from a supporting surface, even if the solid aerosol-generating film is formed by casting a slurry onto the supporting surface.

[0078] The solid aerosol-generating film may be disposed on a support, or the solid aerosol-generating film may be sandwiched between other materials, which may enhance the mechanical stability of the solid aerosol-generating film. For example, the solid aerosol-generating film may be disposed on a layered support.

[0079] The solid aerosol-generating film may be cut or otherwise divided into a plurality of strips or pieces which may be rolled to form an aerosol-generating rod for inclusion in an aerosol-generating article according to the first aspect of the present invention.

[0080] The solid aerosol-generating films may be assembled to form an aerosol-generating rod for inclusion in an aerosol-generating article according to the first aspect of the present invention.

[0081] The solid aerosol-generating film may be textured, which may facilitate assembling the solid aerosol-generating film to form an aerosol-generating rod for inclusion in an aerosol-generating article according to the first aspect of the invention.

[0082] As used herein in connection with the present invention, the term "textured" is used to describe a solid aerosol-generating film that has been crimped, embossed, debossed, perforated, or otherwise modified. A textured solid aerosol-generating film may include a plurality of spaced apart indentations, protrusions, perforations, or a combination thereof.

[0083] The solid aerosol-generating film may be crimped.

[0084] The term "crimped" as used herein in connection with the present invention is intended to be synonymous with the term "crinkled" and is used to describe a solid aerosol-generating film having a plurality of substantially parallel ridges or corrugations.

[0085] The crimped solid aerosol-generating film may have a plurality of ridges or corrugations substantially parallel to the cylindrical axis of the aerosol-generating rod, which may advantageously facilitate assembling the crimped solid aerosol-generating film to form an aerosol-generating rod.

[0086] The solid aerosol-generating films may be textured using suitable well-known machinery for texturing filter tow, paper and other materials.

[0087] The solid aerosol-generating film may be crimped using a crimping unit of the type described in CH-A-691156 that includes a pair of rotatable crimping rollers, although it will be appreciated that the solid aerosol-generating film may also be textured using other suitable machinery and processes that deform or perforate the solid aerosol-generating film.

[0088] The solid aerosol-generating film may be incorporated directly into an aerosol-generating rod for inclusion in an aerosol-generating article according to the first aspect of the present invention.

[0089] The solid aerosol-generating film may be applied to a layered support prior to being incorporated into an aerosol-generating rod for inclusion in an aerosol-generating article according to the first aspect of the present invention. For example, the solid aerosol-generating film may be applied to a surface of a sheet material. Sheet materials suitable for use as a layered support include, but are not limited to, paper, cardboard, and homogenized plant material. For example, the solid aerosol-generating film may be applied to a paper sheet, an aluminum-coated paper sheet, or a polyethylene-coated paper sheet.

[0090] The layered substrate to which the solid aerosol-generating film is applied may be cut or otherwise divided into a plurality of strips or pieces, as described above.

[0091] The layered substrate to which the solid aerosol-generating film is applied may be assembled as described above.

[0092] The layered substrate to which the solid aerosol-generating film is applied may be textured as described above.

[0093] The solid aerosol-generating film may be applied to a tubular support prior to incorporation into an aerosol-generating rod for inclusion in an aerosol-generating article according to the first aspect of the invention. For example, the solid aerosol-generating film may be applied to the inner surface of a hollow tubular support.

[0094] The solid aerosol-generating substrate comprises nicotine.

[0095] As used herein in connection with the present invention, the term "nicotine" is used to describe nicotine, nicotine base, or nicotine salts. In embodiments in which the solid aerosol-generating substrate comprises nicotine base or nicotine salts, the amount of nicotine recited herein is the amount of free base nicotine or the amount of protonated nicotine, respectively.

[0096] The solid aerosol-generating substrate may comprise natural nicotine, or synthetic nicotine, or a combination of natural and synthetic nicotine.

[0097] The solid aerosol-generating substrate may have a nicotine content by weight of 0.5 percent or more, 1 percent or more, 1.5 percent or more, or 2 percent or more.

[0098] The solid aerosol-generating substrate may have a nicotine content of 10 weight percent or less, 8 weight percent or less, 6 weight percent or less, or 4 weight percent or less.

[0099] The solid aerosol-generating substrate may have a nicotine content of from 0.5 weight percent to 10 weight percent, from 0.5 weight percent to 8 weight percent, from 0.5 weight percent to 6 weight percent, or from 0.5 weight percent to 4 weight percent.

[0100] The solid aerosol-generating substrate may have a nicotine content of from 1 weight percent to 10 weight percent, from 1 weight percent to 8 weight percent, from 1 weight percent to 6 weight percent, or from 1 weight percent to 4 weight percent.

[0101] The solid aerosol-generating substrate may have a nicotine content of from 1.5 weight percent to 10 weight percent, from 1.5 weight percent to 8 weight percent, from 1.5 weight percent to 6 weight percent, or from 1.5 weight percent to 4 weight percent.

[0102] The solid aerosol-generating substrate may have a nicotine content of from 2 weight percent to 10 weight percent, from 2 weight percent to 8 weight percent, from 2 weight percent to 6 weight percent, or from 2 weight percent to 4 weight percent.

[0103] The solid aerosol-generating substrate comprises one or more aerosol formers.

[0104] As used herein in connection with the present invention, the term "aerosol former" is used to describe a compound that facilitates the formation of an aerosol during use and that is preferably substantially resistant to thermal decomposition at the operating temperatures of an aerosol-generating system comprising the aerosol-generating article or solid aerosol-generating substrate.

[0105] Examples of suitable aerosol formers include polyhydric alcohols (such as 1,3-butanediol, glycerin, 1,3-propanediol, propylene glycol, and triethylene glycol), esters of polyhydric alcohols (such as glycerol monoacetate, diacetate, or triacetate), and aliphatic esters of mono-, di-, or polycarboxylic acids (such as dimethyl dodecanedioate and dimethyl tetradecanedioate).

[0106] The solid aerosol-generating substrate has a total aerosol-former content of 45 weight percent or greater.

[0107] As used herein with respect to the present invention, the term "total aerosol former content" is used to describe the combined content of all aerosol formers in a solid aerosol-generating substrate.

[0108] The solid aerosol-generating substrate may have a total aerosol-former content by weight of 46 percent or more, 48 percent or more, 50 percent or more, or 52 percent or more.

[0109] The solid aerosol-generating substrate may have a total aerosol-former content of 62 weight percent or less, 60 weight percent or less, 58 weight percent or less, 56 weight percent or less, or 54 weight percent or less.

[0110] The solid aerosol-generating substrate may have a total aerosol former content of 45 weight percent to 62 weight percent, 45 weight percent to 60 weight percent, 45 weight percent to 58 weight percent, 45 weight percent to 56 weight percent, or 45 weight percent to 54 weight percent.

[0111] The solid aerosol-generating substrate may have a total aerosol former content of 42 weight percent to 62 weight percent, 46 weight percent to 60 weight percent, 46 weight percent to 58 weight percent, 46 weight percent to 56 weight percent, or 46 weight percent to 54 weight percent.

[0112] The solid aerosol-generating substrate may have a total aerosol former content of 48 weight percent to 62 weight percent, 48 weight percent to 60 weight percent, 48 weight percent to 58 weight percent, 48 weight percent to 56 weight percent, or 48 weight percent to 54 weight percent.

[0113] The solid aerosol-generating substrate may have a total aerosol former content of 50 weight percent to 62 weight percent, 50 weight percent to 60 weight percent, 50 weight percent to 58 weight percent, 50 weight percent to 56 weight percent, or 50 weight percent to 54 weight percent.

[0114] The solid aerosol-generating substrate may have a total aerosol former content of 52 weight percent to 62 weight percent, 52 weight percent to 60 weight percent, 52 weight percent to 58 weight percent, 52 weight percent to 56 weight percent, or 52 weight percent to 54 weight percent.

[0115] The solid aerosol-generating substrate preferably comprises one or more polyhydric alcohols.

[0116] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 45 weight percent or more, 46 weight percent or more, 48 weight percent or more, 50 weight percent or more, or 52 weight percent or more.

[0117] As used herein in connection with the present invention, the term "total polyhydric alcohol content" is used to describe the combined content of all polyhydric alcohols in a solid aerosol-generating substrate.

[0118] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 62 weight percent or less, 60 weight percent or less, 58 weight percent or less, 56 weight percent or less, or 54 weight percent or less.

[0119] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 45 weight percent to 62 weight percent, 45 weight percent to 60 weight percent, 45 weight percent to 58 weight percent, 45 weight percent to 56 weight percent, or 45 weight percent to 54 weight percent.

[0120] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 46 weight percent to 62 weight percent, 46 weight percent to 60 weight percent, 46 weight percent to 58 weight percent, 46 weight percent to 56 weight percent, or 46 weight percent to 54 weight percent.

[0121] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 48 weight percent to 62 weight percent, 48 weight percent to 60 weight percent, 48 weight percent to 58 weight percent, 48 weight percent to 56 weight percent, or 48 weight percent to 54 weight percent.

[0122] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 50 weight percent to 62 weight percent, 50 weight percent to 60 weight percent, 50 weight percent to 58 weight percent, 50 weight percent to 56 weight percent, or 50 weight percent to 54 weight percent.

[0123] The solid aerosol-generating substrate may have a total polyhydric alcohol content of 52 weight percent to 62 weight percent, 52 weight percent to 60 weight percent, 52 weight percent to 58 weight percent, 52 weight percent to 56 weight percent, or 52 weight percent to 54 weight percent.

[0124] In certain preferred embodiments, the aerosol-generating article according to the first aspect of the invention may comprise a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more polyhydric alcohols, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 percent by weight, a total polyhydric alcohol content of at least 45 percent by weight, and a total carboxylic acid content of at least 0.5 percent by weight.

[0125] In certain preferred embodiments, the aerosol-generating article according to the first aspect of the invention may comprise a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more polyhydric alcohols, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups, do not contain ketone groups and have a pKa of 3.5 or less at 25°C, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 weight percent, a total polyhydric alcohol content of at least 45 weight percent and a total carboxylic acid content of at least 0.5 weight percent.

[0126] In certain preferred embodiments, the aerosol-generating article according to the first aspect of the invention may comprise a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more polyhydric alcohols, and one or more carboxylic acids having a pKa of 3.5 or less at 25°C, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 weight percent, a total polyhydric alcohol content of at least 45 weight percent, and a total carboxylic acid content of at least 0.5 weight percent.

[0127] The solid aerosol-generating substrate preferably comprises one or more polyhydric alcohols selected from 1,3-butanediol, glycerin, 1,3-propanediol, propylene glycol, and triethylene glycol.

[0128] More preferably, the solid aerosol-generating substrate comprises one or more polyhydric alcohols selected from glycerin and propylene glycol.

[0129] Most preferably, the solid aerosol-generating substrate comprises glycerin.

[0130] The solid aerosol-generating substrate may have a glycerin content of 35 weight percent or more, 40 weight percent or more, 45 weight percent or more, 46 weight percent or more, 48 weight percent or more, 50 weight percent or more, or 52 weight percent or more.

[0131] The solid aerosol-generating substrate may have a glycerin content of 62 weight percent or less, 60 weight percent or less, 58 weight percent or less, 56 weight percent or less, or 54 weight percent or less.

[0132] The solid aerosol-generating substrate may have a glycerin content of 35 weight percent to 62 weight percent, 35 weight percent to 60 weight percent, 35 weight percent to 58 weight percent, 35 weight percent to 56 weight percent, or 35 weight percent to 54 weight percent.

[0133] The solid aerosol-generating substrate may have a total glycerin content of 40 weight percent to 62 weight percent, 40 weight percent to 60 weight percent, 40 weight percent to 58 weight percent, 40 weight percent to 56 weight percent, or 40 weight percent to 54 weight percent.

[0134] The solid aerosol-generating substrate may have a glycerin content of 45 weight percent to 62 weight percent, 45 weight percent to 60 weight percent, 45 weight percent to 58 weight percent, 45 weight percent to 56 weight percent, or 45 weight percent to 54 weight percent.

[0135] The solid aerosol-generating substrate may have a glycerin content of 46 weight percent to 62 weight percent, 46 weight percent to 60 weight percent, 46 weight percent to 58 weight percent, 46 weight percent to 56 weight percent, or 46 weight percent to 54 weight percent.

[0136] The solid aerosol-generating substrate may have a glycerin content of 48 weight percent to 62 weight percent, 48 weight percent to 60 weight percent, 48 weight percent to 58 weight percent, 48 weight percent to 56 weight percent, or 48 weight percent to 54 weight percent.

[0137] The solid aerosol-generating substrate may have a total glycerin content of from 50 weight percent to 62 weight percent, from 50 weight percent to 60 weight percent, from 50 weight percent to 58 weight percent, from 50 weight percent to 56 weight percent, or from 50 weight percent to 54 weight percent.

[0138] The solid aerosol-generating substrate may have a total glycerin content of 52 weight percent to 62 weight percent, 52 weight percent to 60 weight percent, 52 weight percent to 58 weight percent, 52 weight percent to 56 weight percent, or 52 weight percent to 54 weight percent.

[0139] In certain preferred embodiments, the aerosol-generating article according to the first aspect of the invention may comprise a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, glycerin, and one or more carboxylic acids which do not contain non-carboxyl alkyl hydroxyl groups and which do not contain ketone groups, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 percent by weight, a glycerin content of 45 percent by weight or more, and a total carboxylic acid content of at least 0.5 percent by weight.

[0140] In certain preferred embodiments, the aerosol-generating article according to the first aspect of the invention may comprise a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, glycerin, and one or more carboxylic acids having a pKa in water of 3.5 or less at 25°C, and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 weight percent, a glycerin content of 45 weight percent or more, and a total carboxylic acid content of at least 0.5 weight percent.

[0141] In certain preferred embodiments, the aerosol-generating article according to the first aspect of the invention may comprise a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, glycerin, and one or more carboxylic acids which contain no non-carboxyl alkyl hydroxyl groups, which contain no ketone groups and which have a pKa in water of 3.5 or less at 25° C., and a susceptor in direct contact with the solid aerosol-generating substrate, the solid aerosol-generating substrate having a total cellulosic agent content of at least 35 percent by weight, a glycerin content of at least 45 percent by weight and a total carboxylic acid content of at least 0.5 percent by weight.

[0142] The solid aerosol-generating substrate comprises one or more carboxylic acids.

[0143] The solid aerosol-generating substrate may comprise a plurality of carboxylic acids, i.e. the solid aerosol-generating substrate may comprise two or more carboxylic acids, for example the solid aerosol-generating substrate may comprise two carboxylic acids, three carboxylic acids, four carboxylic acids or five carboxylic acids.

[0144] The solid aerosol-generating substrate may comprise one or more carboxylic acids that are free of non-carboxyl alkyl hydroxyl groups and that are free of ketone groups.

[0145] As used herein in connection with the present invention, the term "non-carboxyl alkyl hydroxyl group" is used to describe an alkyl hydroxyl group that does not form part of a carboxyl group.

[0146] For example, the solid aerosol-generating substrate may include one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, fumaric acid, maleic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid.

[0147] The solid aerosol-generating substrate may comprise a plurality of carboxylic acids that are free of non-carboxyl alkyl hydroxyl groups and that are free of ketone groups, for example, the solid aerosol-generating substrate may comprise benzoic acid and succinic acid.

[0148] The solid aerosol-generating substrate may comprise one or more carboxylic acids having a pKa in water of 3.5 or less at 25°C.

[0149] The term "carboxylic acid having a pKa in water of 3.5 or less at 25° C." as used herein in connection with the present invention refers to monobasic carboxylic acids having a pKa in water of 3.5 or less at 25° C. and 1 It is used to describe polybasic carboxylic acids having the formula:

[0150] For example, the solid aerosol-generating substrate may include one or more carboxylic acids selected from citric acid, fumaric acid, maleic acid, malic acid, oxalic acid, and salicylic acid.

[0151] The solid aerosol-generating substrate may include a number of carboxylic acids having a pKa in water of 3.5 or less at 25° C. For example, the solid aerosol-generating substrate may include citric acid and malic acid.

[0152] The solid aerosol-generating substrate may comprise one or more carboxylic acids that contain no non-carboxyl alkyl hydroxyl groups, that contain no ketone groups, and that have a pKa in water of 3.5 or less at 25° C. For example, the solid aerosol-generating substrate may comprise one or more carboxylic acids selected from fumaric acid, maleic acid, oxalic acid, and salicylic acid.

[0153] The solid aerosol-generating substrate may include a plurality of carboxylic acids that contain no non-carboxyl alkyl hydroxyl groups, that contain no ketone groups, and that have a pKa in water of 3.5 or less at 25° C. For example, the solid aerosol-generating substrate may include fumaric acid and maleic acid.

[0154] The solid aerosol-generating substrate may comprise one or more carboxylic acids having a pKa in water of 3.6 or greater at 25°C.

[0155] The term "carboxylic acid having a pKa in water of 3.6 or more at 25° C." as used herein in connection with the present invention refers to monobasic carboxylic acids having a pKa in water of 3.6 or more at 25° C. and to monobasic carboxylic acids having a pKa in water of 3.6 or more at 25° C. 1 It is used to describe polybasic carboxylic acids having the formula:

[0156] The solid aerosol-generating substrate may comprise one or more carboxylic acids that contain no non-carboxyl alkyl hydroxyl groups, that contain no ketone groups, and that have a pKa in water of 3.6 or greater at 25° C. For example, the solid aerosol-generating substrate may comprise one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, and succinic acid.

[0157] The solid aerosol-generating substrate may include a plurality of carboxylic acids that contain no non-carboxyl alkyl hydroxyl groups, that contain no ketone groups, and that have a pKa in water of 3.6 or greater at 25° C. For example, the solid aerosol-generating substrate may include acetic acid and benzoic acid.

[0158] The solid aerosol-generating substrate may further comprise one or more carboxylic acids which contain a non-carboxyl alkyl hydroxyl group and have a pKa in water of 3.6 or greater at 25° C. For example, the solid aerosol-generating substrate may further comprise lactic acid.

[0159] The solid aerosol-generating substrate may further comprise one or more carboxylic acids containing a ketone group and having a pKa in water of 3.6 or greater at 25° C. For example, the solid aerosol-generating substrate may further comprise levulinic acid.

[0160] The solid aerosol-generating substrate may include a plurality of carboxylic acids having a pKa in water of 3.6 or greater at 25° C. For example, the solid aerosol-generating substrate may include benzoic acid and lactic acid.

[0161] The solid aerosol-generating substrate may comprise one or more carboxylic acids having a pKa in water of 3.5 or less at 25°C, and one or more carboxylic acids having a pKa in water of 3.6 or more at 25°C.

[0162] For example, the solid aerosol-generating substrate may include one or more carboxylic acids selected from fumaric acid, maleic acid, and malic acid, and one or more carboxylic acids selected from acetic acid, benzoic acid, lactic acid, and levulinic acid.

[0163] For example, the solid aerosol-generating substrate may include fumaric acid and one or more carboxylic acids selected from acetic acid, benzoic acid, lactic acid, and levulinic acid.

[0164] The solid aerosol-generating substrate may comprise one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, undecanoic acid, and C1-C10 saturated alkyl monocarboxylic acids.

[0165] The solid aerosol-generating substrate may include one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid.

[0166] The solid aerosol-generating substrate may comprise one or more carboxylic acids selected from solid aerosol-generating substrates including one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid.

[0167] The solid aerosol-generating substrate may include one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, maleic acid, and malic acid.

[0168] The solid aerosol-generating substrate may include one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, and maleic acid.

[0169] The solid aerosol-generating substrate may include one or more carboxylic acids selected from fumaric acid, maleic acid, and malic acid.

[0170] Preferably, the solid aerosol-generating substrate comprises one or more carboxylic acids selected from fumaric acid and maleic acid.

[0171] More preferably, the solid aerosol-generating substrate comprises fumaric acid.

[0172] The solid aerosol-generating substrate may further comprise one or more carboxylic acids selected from lactic acid and levulinic acid.

[0173] The solid aerosol-generating substrate has a total carboxylic acid content of 0.5 weight percent or greater.

[0174] The term "total carboxylic acid content" as used herein in connection with the present invention is used to describe the combined content of all carboxylic acids in a solid aerosol-generating substrate. For example, if a solid aerosol-generating substrate comprises a plurality of carboxylic acids consisting of benzoic acid and fumaric acid, the term "total carboxylic acid content" describes the combined benzoic acid and fumaric acid content of the solid aerosol-generating substrate.

[0175] The solid aerosol-generating substrate may have a total carboxylic acid content by weight of 1 percent or more, 1.5 percent or more, or 2 percent or more.

[0176] The solid aerosol-generating substrate may have a total carboxylic acid content of 8 weight percent or less, 6 weight percent or less, or 4 weight percent or less.

[0177] The solid aerosol-generating substrate may have a total carboxylic acid content of from 0.5 weight percent to 8 weight percent, from 0.5 weight percent to 6 weight percent, or from 0.5 weight percent to 4 weight percent.

[0178] The solid aerosol-generating substrate may have a total carboxylic acid content of from 1 weight percent to 8 weight percent, from 1 weight percent to 6 weight percent, or from 1 weight percent to 4 weight percent.

[0179] The solid aerosol-generating substrate may have a total carboxylic acid content of from 1.5 weight percent to 8 weight percent, from 1.5 weight percent to 6 weight percent, or from 1.5 weight percent to 4 weight percent.

[0180] The solid aerosol-generating substrate may have a total carboxylic acid content of from 2 weight percent to 8 weight percent, from 2 weight percent to 6 weight percent, or from 2 weight percent to 4 weight percent.

[0181] The molar ratio of total carboxylic acids to nicotine in the solid aerosol-generating substrate may be 0.5:1 or more, 1:1 or more, 1.5:1 or more, or 2:1 or more.

[0182] The molar ratio of total carboxylic acids to nicotine in the solid aerosol-generating substrate may be 5:1 or less, 4.5:1 or less, 4:1 or less, or 3.5:1 or less.

[0183] The molar ratio of total carboxylic acids to nicotine in the solid aerosol-generating substrate may be from 0.5:1 to 5:1, from 0.5:1 to 4.5:1, from 0.5:1 to 4:1, or from 0.5:1 to 3.5:1.

[0184] The molar ratio of total carboxylic acids to nicotine in the solid aerosol-generating substrate may be from 1:1 to 5:1, from 1:1 to 4.5:1, from 1:1 to 4:1, or from 1:1 to 3.5:1.

[0185] The molar ratio of total carboxylic acids to nicotine in the solid aerosol-generating substrate may be from 1.5:1 to 5:1, from 1.5:1 to 4.5:1, from 1.5:1 to 4:1, or from 1.5:1 to 3.5:1.

[0186] The molar ratio of total carboxylic acids to nicotine in the solid aerosol-generating substrate may be from 2:1 to 5:1, from 2:1 to 4.5:1, from 2:1 to 4:1, or from 2:1 to 3.5:1.

[0187] The solid aerosol-generating substrate may have a fumaric acid content of 0.5 weight percent or more, 1 weight percent or more, 1.5 weight percent or more, or 2 weight percent or more.

[0188] The solid aerosol-generating substrate may have a fumaric acid content of 8 weight percent or less, 6 weight percent or less, or 4 weight percent or less.

[0189] The solid aerosol-generating substrate may have a fumaric acid content of from 0.5 weight percent to 8 weight percent, from 0.5 weight percent to 6 weight percent, or from 0.5 weight percent to 4 weight percent.

[0190] The solid aerosol-generating substrate may have a fumaric acid content of from 1 weight percent to 8 weight percent, from 1 weight percent to 6 weight percent, or from 1 weight percent to 4 weight percent.

[0191] The solid aerosol-generating substrate may have a fumaric acid content of from 1.5 weight percent to 8 weight percent, from 1.5 weight percent to 6 weight percent, or from 1.5 weight percent to 4 weight percent.

[0192] The solid aerosol-generating substrate may have a fumaric acid content of from 2 weight percent to 8 weight percent, from 2 weight percent to 6 weight percent, or from 2 weight percent to 4 weight percent.

[0193] The molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate may be 0.5:1 or more, 1:1 or more, 1.5:1 or more, or 2:1 or more.

[0194] The molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate may be 4:1 or less, or 3.5:1 or less, 3:1 or less, or 2.5:1 or less.

[0195] The molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate may be 0.5:1 to 4:1, 0.5:1 to 3.5:1, 0.5:1 to 3:1, or 0.5:1 to 2.5:1.

[0196] The molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate may be 1:1 to 4:1, 1:1 to 3.5:1, 1:1 to 3:1, or 1:1 to 2.5:1.

[0197] The molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate may be from 1.5:1 to 4:1, from 1.5:1 to 3.5:1, from 1.5:1 to 3:1, or from 1.5:1 to 2.5:1.

[0198] The molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate may be 2:1 to 4:1, 2:1 to 3.5:1, 2:1 to 3:1, or 2:1 to 2.5:1.

[0199] The solid aerosol-generating substrate comprises one or more cellulosic agents.

[0200] As used herein in connection with the present invention, the term "cellulosic agent" is used to describe a cellulosic material. Examples of cellulosic agents include cellulosic film formers, cellulosic reinforcing agents, and cellulosic binders.

[0201] The solid aerosol-generating substrate may comprise a plurality of cellulosic agents, i.e. the solid aerosol-generating substrate may comprise two or more cellulosic agents, for example the solid aerosol-generating substrate may comprise two cellulosic agents, three cellulosic agents, four cellulosic agents or five cellulosic agents.

[0202] The solid aerosol-generating substrate may have a total cellulosic agent content of 25 weight percent or more, or 30 weight percent or more.

[0203] The term "total cellulosic agent" as used herein in connection with the present invention is used to describe the combined content of all cellulosic agents in a solid aerosol-generating substrate. For example, if a solid aerosol-generating substrate comprises a plurality of cellulosic agents consisting of a cellulosic film-forming agent, a cellulosic reinforcing agent, and a cellulosic binder, the term "total cellulosic agent content" describes the combined content of the cellulosic film-forming agent, the cellulosic reinforcing agent, and the cellulosic binder of the solid aerosol-generating substrate.

[0204] The solid aerosol-generating substrate preferably has a total cellulosic agent content of 35 weight percent or greater.

[0205] The solid aerosol-generating substrate may have a total cellulosic agent content of 36 weight percent or more, 38 weight percent or more, or 40 weight percent or more.

[0206] The solid aerosol-generating substrate may have a total cellulosic agent content of 52 weight percent or less, 50 weight percent or less, 48 ​​weight percent or less, 46 weight percent or less, or 44 weight percent or less.

[0207] The solid aerosol-generating substrate may have a total cellulosic agent content of 35 weight percent to 52 weight percent, 35 weight percent to 50 weight percent, 35 weight percent to 48 weight percent, 35 weight percent to 46 weight percent, or 35 weight percent to 44 weight percent.

[0208] The solid aerosol-generating substrate may have a total cellulosic agent content of 36 weight percent to 52 weight percent, 36 weight percent to 50 weight percent, 36 weight percent to 48 weight percent, 36 weight percent to 46 weight percent, or 36 weight percent to 44 weight percent.

[0209] The solid aerosol-generating substrate may have a total cellulosic agent content of 38 weight percent to 52 weight percent, 38 weight percent to 50 weight percent, 38 weight percent to 48 weight percent, 38 weight percent to 46 weight percent, or 38 weight percent to 44 weight percent.

[0210] The solid aerosol-generating substrate may have a total cellulosic agent content of from 40 weight percent to 52 weight percent, from 40 weight percent to 50 weight percent, from 40 weight percent to 48 weight percent, from 40 weight percent to 46 weight percent, or from 40 weight percent to 44 weight percent.

[0211] The solid aerosol-generating substrate may comprise one or more cellulosic film-forming agents.

[0212] As used herein in connection with the present invention, the term "cellulosic film former" is used to describe a cellulose polymer that has the ability to form a continuous film, either by itself or in the presence of an auxiliary thickener.

[0213] Advantageously, the solid aerosol-generating substrate may comprise one or more cellulosic film-forming agents selected from carboxymethyl cellulose (CMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxyethyl methyl cellulose (HEMC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), and methyl cellulose (MC).

[0214] More advantageously, the solid aerosol-generating substrate may comprise one or more cellulosic film-forming agents selected from carboxymethylcellulose (CMC), ethylcellulose (EC), methylcellulose (MC), and hydroxypropylmethylcellulose (HPMC).

[0215] Most advantageously, the solid aerosol-generating substrate comprises one or more cellulosic film-forming agents selected from carboxymethylcellulose (CMC) and hydroxypropylmethylcellulose (HPMC).

[0216] Preferably, the solid aerosol-generating substrate comprises carboxymethylcellulose (CMC) and hydroxypropylmethylcellulose (HPMC).

[0217] One or more cellulosic film-forming agents may act as binders for the solid aerosol-generating substrate.

[0218] The solid aerosol-generating substrate may have 15 weight percent or more, 20 weight percent or more, or 25 weight percent or more of the total cellulosic film-forming agents.

[0219] As used herein in connection with the present invention, the term "total cellulosic film-forming agent content" is used to describe the combined content of all cellulosic film-forming agents in the solid aerosol-generating substrate.

[0220] The solid aerosol-generating substrate may have a total cellulosic film-forming agent content of 40 weight percent or less, 35 weight percent or less, or 30 weight percent or less.

[0221] The solid aerosol-generating substrate may have a total cellulosic film-forming agent content of from 15 weight percent to 40 weight percent, from 15 weight percent to 35 weight percent, or from 15 weight percent to 30 weight percent.

[0222] The solid aerosol-generating substrate may have a total cellulosic film-forming agent content of from 20 percent to 40 percent by weight, from 20 percent to 35 percent by weight, or from 20 percent to 30 percent by weight.

[0223] The solid aerosol-generating substrate may have a total cellulosic film-forming agent content of from 25 percent to 40 percent by weight, from 25 percent to 35 percent by weight, or from 25 percent to 30 percent by weight.

[0224] The inclusion of hydroxypropyl methylcellulose in the solid aerosol-generating substrate may advantageously facilitate the manufacture of the solid aerosol-generating substrate. For example, hydroxypropyl methylcellulose may advantageously reduce the overall viscosity of the slurry of the solid aerosol-generating substrate components produced during the manufacture of the solid aerosol-generating substrate. A low viscosity slurry may be easier to flow and easier to mix, move, and handle during the manufacturing process.

[0225] Hydroxypropyl methylcellulose can advantageously act as a binder for the solid aerosol-generating substrate.

[0226] The solid aerosol-generating substrate may have a hydroxypropyl methylcellulose content of 14 weight percent or more, 16 weight percent or more, 18 weight percent or more, or 20 weight percent or more.

[0227] The solid aerosol-generating substrate may have a hydroxypropyl methylcellulose content of 40 weight percent or less, 35 weight percent or less, 30 weight percent or less, or 25 weight percent or less.

[0228] The solid aerosol-generating substrate may have a hydroxypropyl methylcellulose content of from 14 weight percent to 40 weight percent, from 14 weight percent to 35 weight percent, from 14 weight percent to 30 weight percent, or from 14 weight percent to 25 weight percent.

[0229] The solid aerosol-generating substrate may have a hydroxypropyl methylcellulose content of from 16 weight percent to 40 weight percent, from 16 weight percent to 35 weight percent, from 16 weight percent to 30 weight percent, or from 16 weight percent to 25 weight percent.

[0230] The solid aerosol-generating substrate may have a hydroxypropyl methylcellulose content of 18 weight percent to 40 weight percent, 18 weight percent to 35 weight percent, 18 weight percent to 30 weight percent, or 18 weight percent to 25 weight percent.

[0231] The solid aerosol-generating substrate may have a hydroxypropyl methylcellulose content of from 20 weight percent to 40 weight percent, from 20 weight percent to 35 weight percent, from 20 weight percent to 30 weight percent, or from 20 weight percent to 25 weight percent.

[0232] The inclusion of carboxymethylcellulose in the solid aerosol-generating substrate may advantageously reduce or eliminate crusting of the aerosol-generating article according to the first aspect of the invention.

[0233] As used herein in connection with the present invention, the term "crusting" is used to describe the formation of a solid layer on a component of an aerosol-generating article.

[0234] Crusting can occur due to components of the solid aerosol-generating substrate melting and then resolidifying around the components of the aerosol-generating article during its use. Crusting can be a particular problem in the aerosol-generating article according to the first aspect of the invention, which contains a susceptor in direct contact with the solid aerosol-forming substrate. If a crust forms on the susceptor, the susceptor with the crust may become ineffective in heating the solid aerosol-generating substrate. This can disadvantageously lead to one or both of reduced nicotine delivery to the user and reduced aerosol formation from the solid aerosol-generating substrate.

[0235] The solid aerosol-generating substrate may include sodium carboxymethylcellulose.

[0236] The solid aerosol-generating substrate may have a carboxymethylcellulose content of 2 weight percent or more, 3 weight percent or more, 4 weight percent or more, or 5 weight percent or more.

[0237] The solid aerosol-generating substrate may have a carboxymethylcellulose content of 12 weight percent or less, 10 weight percent or less, 8 weight percent or less, or 6 weight percent or less.

[0238] The solid aerosol-generating substrate may have a carboxymethylcellulose content of from 2 weight percent to 12 weight percent, from 2 weight percent to 10 weight percent, from 2 weight percent to 8 weight percent, or from 2 weight percent to 6 weight percent.

[0239] The solid aerosol-generating substrate may have a carboxymethylcellulose content of from 3 weight percent to 12 weight percent, from 3 weight percent to 10 weight percent, from 3 weight percent to 8 weight percent, or from 3 weight percent to 6 weight percent.

[0240] The solid aerosol-generating substrate may have a carboxymethylcellulose content of from 4 weight percent to 12 weight percent, from 4 weight percent to 10 weight percent, from 4 weight percent to 8 weight percent, or from 4 weight percent to 6 weight percent.

[0241] The solid aerosol-generating substrate may have a carboxymethylcellulose content of from 5 weight percent to 12 weight percent, from 5 weight percent to 10 weight percent, from 5 weight percent to 8 weight percent, or from 5 weight percent to 6 weight percent.

[0242] The solid aerosol-generating substrate may include one or more cellulosic reinforcing agents.

[0243] The inclusion of one or more cellulosic reinforcing agents in a solid aerosol-generating substrate may advantageously increase the tensile strength of the solid aerosol-generating substrate. In particular, where the solid aerosol-generating substrate is a solid aerosol-generating film, the inclusion of one or more cellulosic reinforcing agents in a solid aerosol-generating substrate may advantageously increase the tensile strength of the solid aerosol-generating film. Solid aerosol-generating substrates having high tensile strength may advantageously be less likely to deteriorate or break during manufacture and storage.

[0244] Advantageously, the solid aerosol-generating substrate may comprise one or more cellulosic reinforcing agents selected from cellulose fibres, cellulose powder and microcrystalline cellulose (MCC).

[0245] The solid aerosol-generating substrate preferably comprises cellulose fibres, which can be particularly effective in increasing the tensile strength of the solid aerosol-generating substrate.

[0246] The solid aerosol-generating substrate may have a total cellulosic reinforcing agent content of 5 weight percent or more, 10 weight percent or more, or 15 weight percent or more.

[0247] As used herein in connection with the present invention, the term "total cellulosic reinforcing agent content" is used to describe the combined content of all cellulosic reinforcing agents in the solid aerosol-generating substrate.

[0248] The solid aerosol-generating substrate may have a total cellulosic reinforcing agent content of 30 weight percent or less, 25 weight percent or less, or 20 weight percent or less.

[0249] The solid aerosol-generating substrate may have a total cellulosic reinforcing agent content of from 5 weight percent to 30 weight percent, from 5 weight percent to 25 weight percent, or from 5 weight percent to 20 weight percent.

[0250] The solid aerosol-generating substrate may have a total cellulosic reinforcing agent content of from 10 weight percent to 30 weight percent, from 10 weight percent to 25 weight percent, or from 10 weight percent to 20 weight percent.

[0251] The solid aerosol-generating substrate may have a total cellulosic reinforcing agent content of from 15 weight percent to 30 weight percent, from 15 weight percent to 25 weight percent, or from 15 weight percent to 20 weight percent.

[0252] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 0.2 millimetres or more, 0.5 millimetres or more, 0.7 millimetres or more, or 0.9 millimetres or more.

[0253] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 2 millimetres or less, 1.8 millimetres or less, 1.6 millimetres or less, or 1.4 millimetres or less.

[0254] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 0.2 millimetres to 2.0 millimetres, 0.2 millimetres to 1.8 millimetres, 0.2 millimetres to 1.6 millimetres, or 0.2 millimetres to 1.4 millimetres.

[0255] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 0.5 millimetres to 2.0 millimetres, 0.5 millimetres to 1.8 millimetres, 0.5 millimetres to 1.6 millimetres, or 0.5 millimetres to 1.4 millimetres.

[0256] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 0.5 millimetres to 2.0 millimetres, 0.5 millimetres to 1.8 millimetres, 0.5 millimetres to 1.6 millimetres, or 0.5 millimetres to 1.4 millimetres.

[0257] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 0.7 millimetres to 2.0 millimetres, 0.7 millimetres to 1.8 millimetres, 0.7 millimetres to 1.6 millimetres, or 0.7 millimetres to 1.4 millimetres.

[0258] The solid aerosol-generating substrate may comprise cellulose fibres having a length of 0.9 millimetres to 2.0 millimetres, 0.9 millimetres to 1.8 millimetres, 0.9 millimetres to 1.6 millimetres, or 0.9 millimetres to 1.4 millimetres.

[0259] The solid aerosol-generating substrate may have a cellulosic fiber content of 2 weight percent or more, 5 weight percent or more, 10 weight percent or more, or 15 weight percent or more.

[0260] The solid aerosol-generating substrate may have a cellulosic fiber content of 30 weight percent or less, 25 weight percent or less, or 20 weight percent or less.

[0261] The solid aerosol-generating substrate may have a cellulose fiber content of from 2 percent to 30 percent by weight, from 2 percent to 25 percent by weight, or from 2 percent to 20 percent by weight.

[0262] The solid aerosol-generating substrate may have a cellulose fiber content of from 5 weight percent to 30 weight percent, from 5 weight percent to 25 weight percent, or from 5 weight percent to 20 weight percent.

[0263] The solid aerosol-generating substrate may have a cellulose fiber content of from 10 weight percent to 30 weight percent, from 10 weight percent to 25 weight percent, or from 10 weight percent to 20 weight percent.

[0264] The solid aerosol-generating substrate may have a cellulose fiber content of from 15 percent to 30 percent by weight, from 15 percent to 25 percent by weight, or from 15 percent to 20 percent by weight.

[0265] The solid aerosol-generating substrate may comprise microcrystalline cellulose having a D50 particle size of 5 micrometers or more, 10 micrometers or more, or 15 micrometers or more.

[0266] The term "D50 particle size" as used herein in connection with the present invention describes the median particle size of a particulate material. The D50 particle size is the particle size that splits the distribution in half, with half of the particles being larger than the D50 particle size and half of the particles being smaller than the D50 particle size. The particle size distribution may be determined by laser diffraction. For example, the particle size distribution may be determined by laser diffraction using a Malvern Mastersizer 3000 laser diffraction particle size analyzer according to the manufacturer's instructions.

[0267] The solid aerosol-generating substrate may comprise microcrystalline cellulose having a D50 particle size of 100 micrometers or less, 90 micrometers or less, or 80 micrometers or less.

[0268] The solid aerosol-generating substrate may comprise microcrystalline cellulose having a D50 particle size of from 5 micrometers to 100 micrometers, from 5 micrometers to 90 micrometers, or from 5 micrometers to 80 micrometers.

[0269] The solid aerosol-generating substrate may comprise microcrystalline cellulose having a D50 particle size of from 10 micrometers to 100 micrometers, from 10 micrometers to 90 micrometers, or from 10 micrometers to 80 micrometers.

[0270] The solid aerosol-generating substrate may comprise microcrystalline cellulose having a D50 particle size of from 15 micrometers to 100 micrometers, from 15 micrometers to 90 micrometers, or from 150 micrometers to 80 micrometers.

[0271] The solid aerosol-generating substrate may have a microcrystalline cellulose content of 2 weight percent or more, 5 weight percent or more, 10 weight percent or more, or 15 weight percent or more.

[0272] The solid aerosol-generating substrate may have a microcrystalline cellulose content of 30 weight percent or less, 25 weight percent or less, or 20 weight percent or less.

[0273] The solid aerosol-generating substrate may have a microcrystalline cellulose content of from 2 percent to 30 percent by weight, from 2 percent to 25 percent by weight, or from 2 percent to 20 percent by weight.

[0274] The solid aerosol-generating substrate may have a microcrystalline cellulose content of from 5 weight percent to 30 weight percent, from 5 weight percent to 25 weight percent, or from 5 weight percent to 20 weight percent.

[0275] The solid aerosol-generating substrate may have a microcrystalline cellulose content of from 10 weight percent to 30 weight percent, from 10 weight percent to 25 weight percent, or from 10 weight percent to 20 weight percent.

[0276] The solid aerosol-generating substrate may have a microcrystalline cellulose content of from 15 weight percent to 30 weight percent, from 15 weight percent to 25 weight percent, or from 15 weight percent to 20 weight percent.

[0277] The solid aerosol-generating substrate may comprise cellulose powder having a D50 particle size of 25 micrometers or more, 30 micrometers or more, or 35 micrometers or more.

[0278] The solid aerosol-generating substrate may comprise a cellulose powder having a D50 particle size of 250 micrometers or less, 225 micrometers or less, or 200 micrometers or less.

[0279] The solid aerosol-generating substrate may comprise a cellulose powder having a D50 particle size of from 25 micrometers to 250 micrometers, from 25 micrometers to 225 micrometers, or from 25 micrometers to 200 micrometers.

[0280] The solid aerosol-generating substrate may comprise a cellulose powder having a D50 particle size of 30 micrometers to 250 micrometers, 30 micrometers to 225 micrometers, or 30 micrometers to 200 micrometers.

[0281] The solid aerosol-generating substrate may comprise a cellulose powder having a D50 particle size of from 35 micrometers to 250 micrometers, from 35 micrometers to 225 micrometers, or from 35 micrometers to 200 micrometers.

[0282] The solid aerosol-generating substrate may have a cellulose powder content of 2 weight percent or more, 5 weight percent or more, 10 weight percent or more, or 15 weight percent or more.

[0283] The solid aerosol-generating substrate may have a cellulose powder content of 30 weight percent or less, 25 weight percent or less, or 20 weight percent or less.

[0284] The solid aerosol-generating substrate may have a cellulose powder content of from 2 percent to 30 percent by weight, from 2 percent to 25 percent by weight, or from 2 percent to 20 percent by weight.

[0285] The solid aerosol-generating substrate may have a cellulose powder content of from 5 percent to 30 percent by weight, from 5 percent to 25 percent by weight, or from 5 percent to 20 percent by weight.

[0286] The solid aerosol-generating substrate may have a cellulose powder content of from 10 weight percent to 30 weight percent, from 10 weight percent to 25 weight percent, or from 10 weight percent to 20 weight percent.

[0287] The solid aerosol-generating substrate may have a cellulose powder content of from 15 weight percent to 30 weight percent, from 15 weight percent to 25 weight percent, or from 15 weight percent to 20 weight percent.

[0288] The solid aerosol-generating substrate may comprise water.

[0289] The solid aerosol-generating substrate may have a water content of 5 weight percent or more, 10 weight percent or more, 15 weight percent or more, or 17 weight percent or more, based on the total weight of the solid aerosol-generating substrate.

[0290] The solid aerosol-generating substrate may have a water content of 35 percent by weight or less, 30 percent by weight or less, or 25 percent by weight or less, based on the total weight of the solid aerosol-generating substrate.

[0291] The solid aerosol-generating substrate may have a water content of from 5 weight percent to 35 weight percent, from 5 weight percent to 30 weight percent, or from 5 weight percent to 25 weight percent, based on the total weight of the solid aerosol-generating substrate.

[0292] The solid aerosol-generating substrate may have a water content of from 10 weight percent to 35 weight percent, from 10 weight percent to 30 weight percent, or from 10 weight percent to 25 weight percent, based on the total weight of the solid aerosol-generating substrate.

[0293] The solid aerosol-generating substrate may have a water content of from 15 weight percent to 35 weight percent, from 15 weight percent to 30 weight percent, or from 15 weight percent to 25 weight percent, based on the total weight of the solid aerosol-generating substrate.

[0294] The solid aerosol-generating substrate may have a water content of from 17 weight percent to 35 weight percent, from 17 weight percent to 30 weight percent, or from 17 weight percent to 25 weight percent, based on the total weight of the solid aerosol-generating substrate.

[0295] The solid aerosol-generating substrate may include one or more non-cellulosic thickening agents.

[0296] The term "non-cellulosic thickener" as used herein in connection with the present invention is used to describe a non-cellulosic material that, when added to an aqueous or non-aqueous liquid composition, increases the viscosity of the liquid composition without substantially altering other properties of the liquid composition. One or more non-cellulosic thickeners may increase the stability and improve the suspension of ingredients in the liquid composition. A thickener may also be referred to as a "thickener" or a "rheology modifier" or a "viscosifying agent."

[0297] The solid aerosol-generating substrate may comprise one or more non-cellulosic thickening agents selected from alginate, gellan gum, guar gum, gum arabic, locust bean gum, pectin, starch, and xanthan gum.

[0298] The solid aerosol-generating substrate may not comprise iota- or kappa-carrageenan. A solid aerosol-generating substrate that does not comprise iota- or kappa-carrageenan may advantageously remain solid when heated to a temperature of between 180° C. and 350° C. This may advantageously reduce or eliminate crusting in the aerosol-generating article according to the first aspect of the invention.

[0299] The solid aerosol-generating substrate may be agar-free. Agar-free solid aerosol-generating substrate may advantageously remain solid when heated to a temperature of between 180° C. and 350° C. This may advantageously reduce or eliminate crusting in the aerosol-generating article according to the first aspect of the invention.

[0300] The solid aerosol-generating substrate may have 1 weight percent or more, 2 weight percent or more, or 3 weight percent or more of total cellulosic thickener.

[0301] As used herein in connection with the present invention, the term "total non-cellulosic thickener content" is used to describe the combined content of all non-cellulosic thickeners in the solid aerosol-generating substrate.

[0302] The solid aerosol-generating substrate may have a total non-cellulosic thickener content of 10 weight percent or less, 8 weight percent or less, or 6 weight percent or less.

[0303] The solid aerosol-generating substrate may have a total non-cellulosic thickener content of from 1 weight percent to 10 weight percent, from 1 weight percent to 8 weight percent, or from 1 weight percent to 6 weight percent.

[0304] The solid aerosol-generating substrate may have a total non-cellulosic thickener content of from 2 percent to 10 percent by weight, from 2 percent to 8 percent by weight, or from 2 percent to 6 percent by weight.

[0305] The solid aerosol-generating substrate may have a total non-cellulosic thickener content of from 3 weight percent to 10 weight percent, from 3 weight percent to 8 weight percent, or from 3 weight percent to 6 weight percent.

[0306] The solid aerosol-generating substrate may include one or more flavourants.

[0307] Suitable flavouring agents are known in the art and include, but are not limited to, menthol.

[0308] As used herein in connection with the present invention, the term "menthol" is used to describe the compound 2-isopropyl-5-methylcyclohexanol in any of its isomeric forms.

[0309] As used herein in connection with the present invention, the term "total flavourant content" is used to describe the combined content of all flavourants in a solid aerosol-generating substrate.

[0310] The solid aerosol-generating substrate may have a total flavorant content of 0.5 weight percent or more, 1 weight percent or more, 2 weight percent or more, or 3 weight percent or more.

[0311] The solid aerosol-generating substrate may have a total flavorant content of 6 weight percent or less, 5 weight percent or less, or 4 weight percent or less.

[0312] The solid aerosol-generating substrate may have a total flavourant content of from 0.5 weight percent to 6 weight percent, from 0.5 weight percent to 5 weight percent, or from 0.5 weight percent to 4 weight percent.

[0313] The solid aerosol-generating substrate may have a total flavourant content of from 1 weight percent to 6 weight percent, from 1 weight percent to 5 weight percent, or from 1 weight percent to 4 weight percent.

[0314] The solid aerosol-generating substrate may have a total flavourant content of from 2 weight percent to 6 weight percent, from 2 weight percent to 5 weight percent, or from 2 weight percent to 4 weight percent.

[0315] The solid aerosol-generating substrate may have a total flavourant content of from 3 percent to 6 percent, from 3 percent to 5 percent, or from 3 percent to 4 percent by weight.

[0316] The solid aerosol-generating substrate may be a substantially tobacco-free solid aerosol-generating substrate.

[0317] As used herein in connection with the present invention, the term "substantially tobacco-free solid aerosol-generating substrate" is used to describe a solid aerosol-generating substrate having a tobacco content of less than 1 percent by weight. For example, the solid aerosol-generating substrate may have a tobacco content of less than 0.75 percent by weight, less than 0.5 percent by weight, or less than 0.25 percent by weight.

[0318] The solid aerosol-generating substrate may be a tobacco-free aerosol-generating film.

[0319] As used herein in connection with the present invention, the term "tobacco-free solid aerosol-generating substrate" is used to describe a solid aerosol-generating substrate having zero percent tobacco content by weight.

[0320] The aerosol-generating article may have any desired shape, for example, the aerosol-generating article may be substantially cylindrical.

[0321] The aerosol-generating article may have any desired transverse cross-section, for example, the aerosol-generating article may have a substantially circular, oval, or elliptical transverse cross-section.

[0322] The aerosol-generating article may have any desired length, for example, the aerosol-generating article may have a length of 30 millimeters to 70 millimeters, 35 millimeters to 65 millimeters, or 40 millimeters to 60 millimeters.

[0323] The aerosol-generating article may have any desired width, for example, the aerosol-generating article may have a width of from 5 millimeters to 10 millimeters, from 6 millimeters to 9 millimeters, or from 7 millimeters to 8 millimeters.

[0324] The aerosol-generating article may comprise an aerosol-generating rod comprising a solid aerosol-generating substrate.

[0325] The aerosol-generating article comprises a susceptor in direct contact with a solid aerosol-generating substrate.

[0326] By including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids which are free of non-carboxyl alkyl hydroxyl groups and which are free of ketone groups, corrosion of the susceptor may be advantageously reduced or prevented.

[0327] By including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids having a pKa in water of 3.5 or less at 25° C., corrosion of the susceptor may be advantageously reduced or prevented.

[0328] By including in the solid aerosol-generating substrate of the aerosol-generating article according to the first aspect of the invention one or more carboxylic acids which are free of non-carboxyl alkyl hydroxyl groups, free of ketone groups and have a pKa in water of 3.5 or less at 25° C., corrosion of the susceptor may be advantageously reduced or prevented.

[0329] The susceptor may be located within an aerosol-generating rod that contains the solid aerosol-generating substrate.

[0330] The susceptor may be located within the solid aerosol-generating substrate.

[0331] The solid aerosol-generating substrate may at least partially surround the susceptor.

[0332] The solid aerosol-generating substrate may be disposed on the susceptor. For example, if the solid aerosol-generating substrate is a solid aerosol-generating film, the susceptor may be at least partially covered by the solid aerosol-generating film.

[0333] The susceptor may be at least partially embedded within the solid aerosol-generating substrate, for example, when the solid aerosol-generating substrate is a solid aerosol-generating gel, the susceptor may be at least partially embedded within the solid aerosol-generating gel.

[0334] The susceptor may be an elongated susceptor.

[0335] As used herein in connection with the present invention, the term "elongated" is used to describe a susceptor that has a length that is greater than its width. For example, the length of a susceptor may be at least twice its width.

[0336] The susceptor may have any desired length. For example, the susceptor may have a length between 6 millimeters and 18 millimeters, between 8 millimeters and 16 millimeters, or between 10 millimeters and 14 millimeters.

[0337] The susceptor may have a length that is substantially the same as the length of the solid aerosol-generating substrate, or substantially the same as the length of the aerosol-generating rod that includes the solid aerosol-generating substrate.

[0338] The susceptor may extend along the longitudinal axis of the aerosol-generating article.

[0339] The susceptor may have any desired width. For example, the susceptor may have a width between 2 millimeters and 8 millimeters, between 3 millimeters and 7 millimeters, or between 4 millimeters and 6 millimeters.

[0340] The susceptor may have any desired thickness. For example, the susceptor may have a thickness of 30 micrometers to 90 micrometers, 40 micrometers to 80 micrometers, or 50 micrometers to 70 micrometers.

[0341] The susceptor element may be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from a solid aerosol-generating substrate.

[0342] The susceptor preferably comprises a metal, an alloy or carbon.

[0343] The susceptor may include or consist of a ferromagnetic material (e.g., a ferromagnetic alloy, ferritic iron, or ferromagnetic steel or stainless steel). A suitable susceptor may include or consist of aluminum.

[0344] The susceptor may be formed from 400 series stainless steel, such as grade 410 stainless steel, or grade 420 stainless steel, or grade 430 stainless steel. Different materials dissipate different amounts of energy when positioned in electromagnetic fields having similar values ​​of frequency and field strength.

[0345] The susceptor may include a non-metallic core having a metallic layer disposed thereon (eg, a metallic track formed on the surface of a ceramic core).

[0346] The susceptor may have a protective outer layer, for example a protective outer ceramic layer or a protective outer glass layer.

[0347] The susceptor may include a protective outer coating formed of glass, ceramic, or an inert metal.

[0348] The aerosol-generating article may include one or more other components.

[0349] The one or more other components may include one or more of an upstream element, a support element, an aerosol cooling element, and a mouthpiece element.

[0350] The aerosol-generating article may comprise an upstream element located at a distal end of the aerosol-generating article.

[0351] The upstream element may be located immediately upstream of the solid aerosol-generating substrate.

[0352] The upstream element may advantageously prevent direct contact with the solid aerosol-generating substrate, which may advantageously help to prevent displacement or deformation of the susceptor during transport and handling of the aerosol-generating article.

[0353] The upstream element can include a plug of porous material, for example, the upstream element can include a cellulose acetate plug.

[0354] The upstream element may have any desired shape, for example, the upstream element may be substantially cylindrical.

[0355] The upstream element may have any desired transverse cross-section. For example, the support element may have a substantially circular, oval, or elliptical transverse cross-section.

[0356] The upstream element may have any desired length. For example, the upstream element may have a length of 1 mm to 10 mm, 1 mm to 8 mm, or 1 mm to 6 mm. For example, the upstream element may have a length of 3 mm to 10 mm, 3 mm to 8 mm, or 3 mm to 6 mm.

[0357] The upstream element may have any desired width. For example, the upstream element may have a width of 5 millimeters to 10 millimeters, 6 millimeters to 9 millimeters, or 7 millimeters to 8 millimeters. The upstream element may have substantially the same width as the width of the aerosol-generating article.

[0358] The aerosol-generating article may comprise a support element located between the solid aerosol-generating substrate and the proximal end of the aerosol-generating article.

[0359] The support element may be located immediately downstream of the solid aerosol-generating substrate.

[0360] The support element may comprise a hollow tubular segment, for example, the support element may comprise a hollow cellulose acetate tube.

[0361] The hollow tubular segment may define a longitudinal cavity that provides an unrestricted flow channel.

[0362] The support element may have any desired shape, for example, the support element may be substantially cylindrical.

[0363] The support elements may have any desired cross-section. For example, the support elements may have a substantially circular, oval, or elliptical cross-section.

[0364] The support element may have any desired length. For example, the support element may have a length of 5 mm to 15 mm, 5 mm to 12 mm, or 5 mm to 10 mm. For example, the support element may have a length of 7 mm to 15 mm, 7 mm to 12 mm, or 7 mm to 10 mm.

[0365] The support element may have any desired width. For example, the support element may have a width of 5 millimeters to 10 millimeters, 6 millimeters to 9 millimeters, or 7 millimeters to 8 millimeters. The support element may have a width that is substantially the same as the width of the aerosol-generating article.

[0366] The aerosol-generating article may include a mouthpiece located at the proximal end of the aerosol-generating article.

[0367] The mouthpiece element may comprise a plug of porous material, for example, the mouthpiece element may comprise a cellulose acetate plug.

[0368] The mouthpiece element may include a cavity at the mouth end.

[0369] The oral end cavity may be defined by a hollow tubular element provided at the proximal end of the mouthpiece element.

[0370] The mouth end cavity may be defined by a wrapper.

[0371] The mouthpiece element may have any desired shape, for example, the mouthpiece element may be substantially cylindrical.

[0372] The mouthpiece elements may have any desired transverse cross-section. For example, the mouthpiece elements may have a substantially circular, oval, or elliptical transverse cross-section.

[0373] The mouthpiece may have any desired length. For example, the mouthpiece element may have a length of 5 mm to 20 mm, 5 mm to 15 mm, or 5 mm to 10 mm. For example, the mouthpiece element may have a length of 6 mm to 20 mm, 6 mm to 15 mm, or 6 mm to 10 mm. For example, the mouthpiece element may have a length of 7 mm to 20 mm, 7 mm to 15 mm, or 7 mm to 10 mm.

[0374] The mouthpiece element may have any desired width. For example, the mouthpiece element may have a width of 5 millimeters to 10 millimeters, 6 millimeters to 9 millimeters, or 7 millimeters to 8 millimeters. The mouthpiece element may have substantially the same width as the width of the aerosol-generating article.

[0375] The aerosol-generating article may comprise an aerosol cooling element located between the solid aerosol-generating substrate and the proximal end of the aerosol-generating article.

[0376] Where the aerosol-generating article comprises a mouthpiece element, the aerosol cooling element may be located immediately upstream of the mouthpiece element.

[0377] Where the aerosol-generating article comprises a support element, the aerosol-cooling element may be located immediately downstream of the support element.

[0378] The aerosol cooling element may comprise a hollow tubular segment, for example, the aerosol cooling element may comprise a hollow cellulose acetate tube.

[0379] The hollow tubular segment may define a longitudinal cavity that provides an unrestricted flow channel.

[0380] The aerosol cooling element may have any desired shape, for example the mouthpiece element may be substantially cylindrical.

[0381] The aerosol cooling element may have any desired cross-section. For example, the aerosol cooling element may have a substantially circular, oval, or elliptical cross-section.

[0382] The aerosol cooling element may have any desired length. For example, the aerosol cooling element may have a length of 5 mm to 20 mm, or 5 mm to 15 mm. For example, the aerosol cooling element may have a length of 6 mm to 20 mm, or 6 mm to 15 mm. For example, the aerosol cooling element may have a length of 7 mm to 20 mm, or 7 mm to 15 mm.

[0383] The aerosol cooling element may have any desired width. For example, the aerosol cooling element may have a width of 5 millimeters to 10 millimeters, 6 millimeters to 9 millimeters, or 7 millimeters to 8 millimeters. The aerosol cooling element may have a width that is substantially the same as the width of the aerosol-generating article.

[0384] The solid aerosol-generating substrate, the susceptor, and one or more other components of the aerosol-generating article may be assembled within one or more wrappers to form the aerosol-generating article, for example, the solid aerosol-generating substrate, the susceptor, and one or more other components of the aerosol-generating article may be assembled within one or more wrappers to form an elongated rod.

[0385] Suitable wrappers for use in the aerosol-generating article according to the first aspect of the invention are known in the art and include, but are not limited to, cigarette paper, filter plug wrap, tipping paper, metallized paper, metal foil, and metal foil paper laminates.

[0386] The aerosol-generating article may comprise a ventilation zone located between the solid aerosol-generating substrate and the proximal end of the aerosol-generating article.

[0387] Where the aerosol-generating article comprises an aerosol cooling element, ventilation zones may be provided at locations along the aerosol cooling element.

[0388] The aerosol-generating article may have a breathability level of 10 percent or greater, 15 percent or greater, 20 percent or greater, or 25 percent or greater.

[0389] The aerosol-generating article may have a breathability level of 50 percent or less, 45 percent or less, or 40 percent or less.

[0390] The aerosol-generating article may have a breathability level of between 10 percent and 50 percent, between 10 percent and 45 percent, or between 10 percent and 40 percent.

[0391] The aerosol-generating article may have a breathability level of between 15 percent and 50 percent, between 15 percent and 45 percent, or between 15 percent and 40 percent.

[0392] The aerosol-generating article may have a breathability level of between 20 percent and 50 percent, between 20 percent and 45 percent, or between 20 percent and 40 percent.

[0393] The aerosol-generating article may have a breathability level of between 25 percent and 50 percent, between 25 percent and 45 percent, or between 25 percent and 40 percent.

[0394] The aerosol-generating article may have a breathability level of between 30 percent and 50 percent, between 30 percent and 45 percent, or between 30 percent and 40 percent.

[0395] An aerosol-generating article according to the first aspect of the present invention may resemble a conventional lighted cigarette.

[0396] The aerosol-generating article according to the first aspect of the invention may be assembled using known methods and machinery.

[0397] According to a second aspect of the present invention, there is provided an aerosol generating system comprising an aerosol-generating article according to the first aspect of the present invention and an electrically operated aerosol generating device including an inductor configured to heat a solid aerosol-generating substrate of the aerosol-generating article.

[0398] An aerosol generating system may comprise a consumable aerosol generating article according to the first aspect of the invention and a reusable electrically powered aerosol generating device configured to heat a solid aerosol-generating substrate of the aerosol-generating article.

[0399] An electrically operated aerosol generating device may include a housing defining a device cavity configured to receive at least a portion of an aerosol generating article.

[0400] An electrically operated aerosol generating device may include a housing defining a device cavity configured to receive at least a distal portion of an aerosol generating article.

[0401] The electrically powered aerosol generating device may be a hand-held electrically powered aerosol generating device.

[0402] An electrically operated aerosol generating device may include a power source and control electronics.

[0403] An electrically operated aerosol generating device may include a battery and control electronics.

[0404] An electrically operated aerosol generating device may comprise an inductor that includes one or more induction coils. EXAMPLES

[0405] The following provides a non-exhaustive list of non-limiting examples, any one or more of the features of which may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0406] Example 1: An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups. Example 2: An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups and that do not contain ketone groups. Example 3: An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that are free of non-carboxyl hydroxyl groups. Example 4: An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that do not contain non-carboxyl hydroxyl groups and that do not contain ketone groups. Example 5: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids having a pKa in water of 3.5 or less at 25°C. Example 6: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that are free of non-carboxyl alkyl hydroxyl groups and have a pKa in water of 3.5 or less at 25°C. Example 7: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that do not contain non-carboxyl alkyl hydroxyl groups, do not contain ketone groups, and have a pKa in water of 3.5 or less at 25°C. Example 8: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that contain no non-carboxyl hydroxyl groups and have a pKa in water of 3.5 or less at 25°C. Example 9: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids that contain no non-carboxyl hydroxyl groups, that contain no ketone groups, and that have a pKa in water of 3.5 or less at 25°C. Example 10: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, undecanoic acid, and C1-C10 saturated alkyl monocarboxylic acids. Example 11: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid. Example 12: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid. Example 13: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, maleic acid, and malic acid. Example 14: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, and maleic acid. Example 15: 1. An aerosol-generating article for use in an aerosol generating system, the aerosol-generating article comprising a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids selected from fumaric acid, maleic acid, and malic acid. Example 16: An aerosol-generating article according to any one of Examples 1 to 53, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from fumaric acid and maleic acid. Example 17: An aerosol-generating article according to any one of Examples 1 to 54, wherein the solid aerosol-generating substrate comprises fumaric acid. Example 18: An aerosol-generating article according to any one of Examples 1 to 17, wherein the solid aerosol-generating substrate does not comprise iota-carrageenan or kappa-carrageenan. Example 19: An aerosol-generating article according to any one of Examples 1 to 18, wherein the solid aerosol-generating substrate does not comprise agar. Example 20: An aerosol-generating article according to any one of Examples 1 to 19, wherein the solid aerosol-generating substrate remains solid when heated to a temperature between 180 degrees Celsius and 350 degrees Celsius. Example 21: An aerosol-generating article according to any one of Examples 1 to 19, wherein the solid aerosol-generating substrate remains solid when heated to a temperature between 200 degrees Celsius and 320 degrees Celsius. Example 22: An aerosol-generating article according to any one of Examples 1 to 19, wherein the solid aerosol-generating substrate remains solid when heated to a temperature between 220 degrees Celsius and 300 degrees Celsius. Example 23: An aerosol-generating article according to any one of Examples 1 to 19, wherein the solid aerosol-generating substrate remains solid when heated to a temperature between 240 degrees Celsius and 280 degrees Celsius. Example 24: An aerosol-generating article according to any one of Examples 1 to 23, wherein the solid aerosol-generating substrate has a nicotine content of 0.5 weight percent or more. Example 25: An aerosol-generating article according to any one of Examples 1 to 124, wherein the solid aerosol-generating substrate has a nicotine content of 1 weight percent or more. Example 26: An aerosol-generating article according to any one of Examples 1 to 125, wherein the solid aerosol-generating substrate has a nicotine content of 1.5 weight percent or more. Example 27: An aerosol-generating article according to any one of Examples 1 to 26, wherein the solid aerosol-generating substrate has a nicotine content of 2 percent by weight or more. Example 28: An aerosol-generating article according to any one of Examples 1 to 27, wherein the solid aerosol-generating substrate has a nicotine content of 10 weight percent or less. Example 29: An aerosol-generating article according to any one of Examples 1 to 28, wherein the solid aerosol-generating substrate has a nicotine content of 8 percent by weight or less. Example 30: An aerosol-generating article according to any one of Examples 1 to 29, wherein the solid aerosol-generating substrate has a nicotine content of 6 percent by weight or less. Example 31: An aerosol-generating article according to any one of Examples 1 to 30, wherein the solid aerosol-generating substrate has a nicotine content of 4 percent by weight or less. Example 32: An aerosol-generating article according to any one of Examples 1 to 31, wherein the solid aerosol-generating substrate has a total aerosol former content of 45 weight percent or more. Example 33: An aerosol-generating article according to any one of Examples 1 to 32, wherein the solid aerosol-generating substrate has a total aerosol former content of 46 weight percent or more. Example 34: An aerosol-generating article according to any one of Examples 1 to 33, wherein the solid aerosol-generating substrate has a total aerosol former content of 48 weight percent or more. Example 35: An aerosol-generating article according to any one of Examples 1 to 34, wherein the solid aerosol-generating substrate has a total aerosol former content of 50 weight percent or more. Example 36: An aerosol-generating article according to any one of Examples 1 to 35, wherein the solid aerosol-generating substrate has a total aerosol former content of 52 weight percent or more. Example 37: An aerosol-generating article according to any one of Examples 1 to 36, wherein the solid aerosol-generating substrate has a total aerosol former content of 62 weight percent or less. Example 38: An aerosol-generating article according to any one of Examples 1 to 37, wherein the solid aerosol-generating substrate has a total aerosol former content of 60 weight percent or less. Example 39: An aerosol-generating article according to any one of Examples 1 to 38, wherein the solid aerosol-generating substrate has a total aerosol former content of 58 weight percent or less. Example 40: An aerosol-generating article according to any one of Examples 1 to 39, wherein the solid aerosol-generating substrate has a total aerosol former content of 56 weight percent or less. Example 41: An aerosol-generating article according to any one of Examples 1 to 40, wherein the solid aerosol-generating substrate has a total aerosol former content of 54 weight percent or less. Example 42: An aerosol-generating article according to any one of Examples 1 to 41, wherein the solid aerosol-generating substrate comprises one or more polyhydric alcohols. Example 43: The aerosol-generating article according to example 42, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 45 weight percent or greater. Example 44: An aerosol-generating article according to embodiment 42 or 43, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 46 weight percent or greater. Example 45: The aerosol-generating article of any one of Examples 42-44, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 48 weight percent or greater. Example 46: The aerosol-generating article of any one of Examples 42-45, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 50 weight percent or greater. Example 47: The aerosol-generating article of any one of Examples 42-46, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 52 weight percent or greater. Example 48: The aerosol-generating article of any one of Examples 42-47, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 62 weight percent or less. Example 49: The aerosol-generating article of any one of Examples 42-48, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 60 weight percent or less. Example 50: 50. The aerosol-generating article of any one of Examples 42-49, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 58 weight percent or less. Example 51: The aerosol-generating article of any one of Examples 42-50, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 56 weight percent or less. Example 52: The aerosol-generating article of any one of Examples 42-51, wherein the solid aerosol-generating substrate has a total polyhydric alcohol content of 54 weight percent or less. Example 53: The aerosol-generating article according to any one of Examples 42 to 52, wherein the solid aerosol-generating substrate comprises one or more polyhydric alcohols selected from 1,3-butanediol, glycerin, 1,3-propanediol, propylene glycol, and triethylene glycol. Example 54: An aerosol-generating article according to any one of Examples 42 to 53, wherein the solid aerosol-generating substrate comprises one or more polyhydric alcohols selected from glycerin and propylene glycol. Example 55: An aerosol-generating article according to any one of Examples 42 to 54, wherein the solid aerosol-generating substrate comprises glycerin. Example 56: An aerosol-generating article according to Example 55, wherein the solid aerosol-generating substrate has a glycerin content of 35 weight percent or greater. Example 57: 57. An aerosol-generating article according to embodiment 55 or 56, wherein the solid aerosol-generating substrate has a glycerin content of 40 weight percent or more. Example 58: The aerosol-generating article of any one of Examples 55-57, wherein the solid aerosol-generating substrate has a glycerin content of 45 weight percent or more. Example 59: The aerosol-generating article of any one of Examples 55-58, wherein the solid aerosol-generating substrate has a glycerin content of 46 weight percent or more. Example 60: 60. The aerosol-generating article of any one of Examples 55-59, wherein the solid aerosol-generating substrate has a glycerin content of 48 weight percent or more. Example 61: The aerosol-generating article of any one of Examples 55-60, wherein the solid aerosol-generating substrate has a glycerin content of 50 weight percent or more. Example 62: The aerosol-generating article of any one of Examples 55-61, wherein the solid aerosol-generating substrate has a glycerin content of 52 weight percent or more. Example 63: The aerosol-generating article of any one of Examples 55-62, wherein the solid aerosol-generating substrate has a glycerin content of 62 weight percent or less. Example 64: The aerosol-generating article of any one of Examples 55-63, wherein the solid aerosol-generating substrate has a glycerin content of 60 weight percent or less. Example 65: The aerosol-generating article of any one of Examples 55-64, wherein the solid aerosol-generating substrate has a glycerin content of 58 weight percent or less. Example 66: The aerosol-generating article of any one of Examples 55-65, wherein the solid aerosol-generating substrate has a glycerin content of 56 weight percent or less. Example 67: The aerosol-generating article of any one of Examples 55-66, wherein the solid aerosol-generating substrate has a glycerin content of 54 weight percent or less. Example 68: An aerosol-generating article according to any one of Examples 1 to 67, wherein the solid aerosol-generating substrate comprises a plurality of carboxylic acids. Example 69: An aerosol-generating article according to any one of Examples 1 to 68, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids containing non-carboxyl hydroxyl groups. Example 70: An aerosol-generating article according to any one of Examples 1 to 69, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids containing non-carboxyl alkyl hydroxyl groups. Example 71: An aerosol-generating article according to any one of Examples 1 to 70, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids containing a ketone group. Example 72: An aerosol-generating article according to any one of Examples 1 to 71, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids having a pKa in water of 3.6 or greater at 25° C. Example 73: An aerosol-generating article according to any one of Examples 1 to 72, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from acetic acid, benzoic acid, lactic acid, and levulinic acid. Example 74: An aerosol-generating article according to any one of Examples 1 to 73, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 0.5 weight percent or greater. Example 75: An aerosol-generating article according to any one of Examples 1-74, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 1 weight percent or greater. Example 76: An aerosol-generating article according to any one of Examples 1-75, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 1.5 weight percent or greater. Example 77: An aerosol-generating article according to any one of Examples 1 to 76, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 2 weight percent or greater. Example 78: An aerosol-generating article according to any one of Examples 1-77, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 8 weight percent or less. Example 79: An aerosol-generating article according to any one of Examples 1-78, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 6 weight percent or less. Example 80: An aerosol-generating article according to any one of Examples 1-79, wherein the solid aerosol-generating substrate has a total carboxylic acid content of 4 weight percent or less. Example 81: 81. An aerosol-generating article according to any one of Examples 1 to 80, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 0.5:1 or greater. Example 82: 82. An aerosol-generating article according to any one of Examples 1 to 81, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 1:1 or greater. Example 83: 83. An aerosol-generating article according to any one of Examples 1 to 82, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 1.5:1 or greater. Example 84: 84. An aerosol-generating article according to any one of Examples 1 to 83, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 2:1 or greater. Example 85: An aerosol-generating article according to any one of Examples 1 to 84, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 5:1 or less. Example 86: An aerosol-generating article according to any one of Examples 1 to 85, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 4.5:1 or less. Example 87: An aerosol-generating article according to any one of Examples 1 to 86, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 4:1 or less. Example 88: An aerosol-generating article according to any one of Examples 1 to 87, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is 3.5:1 or less. Example 89: An aerosol-generating article according to any one of Examples 1 to 88, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 0.5 weight percent or more. Example 90: 89. An aerosol-generating article according to any one of Examples 1 to 89, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 1 weight percent or more. Example 91: 91. An aerosol-generating article according to any one of Examples 1 to 90, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 1.5 weight percent or more. Example 92: 92. An aerosol-generating article according to any one of Examples 1 to 91, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 2 percent by weight or more. Example 93: An aerosol-generating article according to any one of Examples 1 to 92, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 8 percent by weight or less. Example 94: An aerosol-generating article according to any one of Examples 1 to 93, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 6 percent by weight or less. Example 95: An aerosol-generating article according to any one of Examples 1 to 94, wherein the solid aerosol-generating substrate comprises fumaric acid, the solid aerosol-generating substrate having a fumaric acid content of 4 weight percent or less. Example 96: 6. An aerosol-generating article according to any one of Examples 1 to 95, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 0.5:1 or greater. Example 97: 7. An aerosol-generating article according to any one of Examples 1 to 96, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 1:1 or greater. Example 98: 8. An aerosol-generating article according to any one of Examples 1 to 97, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 1.5:1 or greater. Example 99: An aerosol-generating article according to any one of Examples 1 to 98, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 2:1 or greater. Example 100: 99. An aerosol-generating article according to any one of Examples 1 to 99, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 4:1 or less. Example 101: An aerosol-generating article according to any one of Examples 1 to 100, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 3.5:1 or less. Example 102: 102. An aerosol-generating article according to any one of Examples 1 to 101, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 3:1 or less. Example 103: 103. An aerosol-generating article according to any one of Examples 1 to 102, wherein the solid aerosol-generating substrate comprises fumaric acid, and the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is 2.5:1 or less. Example 104: An aerosol-generating article according to any one of Examples 1 to 103, wherein the solid aerosol-generating substrate comprises a plurality of cellulosic agents. Example 105: An aerosol-generating article according to any one of Examples 1-104, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 25 weight percent or more. Example 106: An aerosol-generating article according to any one of Examples 1-105, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 30 weight percent or more. Example 107: An aerosol-generating article according to any one of Examples 1-106, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 35 weight percent or greater. Example 108: An aerosol-generating article according to any one of Examples 1-107, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 36 weight percent or greater. Example 109: An aerosol-generating article according to any one of Examples 1-108, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 38 weight percent or greater. Example 110: An aerosol-generating article according to any one of Examples 1-109, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 40 weight percent or more. Example 111: An aerosol-generating article according to any one of Examples 1 to 110, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 52 weight percent or less. Example 112: An aerosol-generating article according to any one of Examples 1-111, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 50 weight percent or less. Example 113: An aerosol-generating article according to any one of Examples 1 to 112, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 48 weight percent or less. Example 114: An aerosol-generating article according to any one of Examples 1-113, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 46 weight percent or less. Example 115: An aerosol-generating article according to any one of Examples 1-114, wherein the solid aerosol-generating substrate has a total cellulosic agent content of 44 weight percent or less. Example 116: An aerosol-generating article according to any one of Examples 1 to 115, wherein the solid aerosol-generating substrate comprises one or more cellulosic film-forming agents. Example 117: The aerosol-generating article according to Example 116, wherein the solid aerosol-generating substrate comprises one or more cellulosic film-forming agents selected from carboxymethyl cellulose (CMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxyethyl methyl cellulose (HEMC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), and methyl cellulose (MC). Example 118: The aerosol-generating article according to example 116 or 117, wherein the solid aerosol-generating substrate comprises one or more cellulosic film-forming agents selected from carboxymethylcellulose (CMC), ethylcellulose (EC), methylcellulose (MC), and hydroxypropylmethylcellulose (HPMC). Example 119: The aerosol-generating article according to any one of Examples 116-118, wherein the solid aerosol-generating substrate comprises one or more cellulosic film-forming agents selected from carboxymethylcellulose (CMC) and hydroxypropylmethylcellulose (HPMC). Example 120: The aerosol-generating article according to any one of Examples 116-119, wherein the solid aerosol-generating substrate comprises carboxymethylcellulose (CMC) and hydroxypropylmethylcellulose (HPMC). Example 121: The aerosol-generating article according to any one of Examples 116-120, wherein the one or more cellulosic film-forming agents act as a binder for the solid aerosol-generating substrate. Example 122: The aerosol-generating article of any one of Examples 116-121, wherein the solid aerosol-generating substrate has a total cellulosic film-forming agent content of 15 weight percent or more. Example 123: The aerosol-generating article according to any one of Examples 116-122, wherein the solid aerosol-generating substrate has a total cellulosic film-forming agent content of 20 weight percent or more. Example 124: The aerosol-generating article of any one of Examples 116-123, wherein the solid aerosol-generating substrate has a total cellulosic film-forming agent content of 25 weight percent or more. Example 125: The aerosol-generating article of any one of Examples 116-124, wherein the solid aerosol-generating substrate has a total cellulosic film-forming agent content of 40 weight percent or less. Example 126: The aerosol-generating article according to any one of Examples 116-125, wherein the solid aerosol-generating substrate has a total cellulosic film-forming agent content of 35 weight percent or less. Example 127: The aerosol-generating article according to any one of Examples 116-126, wherein the solid aerosol-generating substrate has a total cellulosic film-forming agent content of 30 weight percent or less. Example 128: The aerosol-generating article of any one of Examples 116-127, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 14 weight percent or greater. Example 129: The aerosol-generating article of any one of Examples 116-128, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 16 weight percent or greater. Example 130: The aerosol-generating article of any one of Examples 116-129, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 18 weight percent or greater. Example 131: The aerosol-generating article of any one of Examples 116-130, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 20 weight percent or more. Example 132: The aerosol-generating article of any one of Examples 116-131, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 40 weight percent or less. Example 133: The aerosol-generating article of any one of Examples 116-132, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 35 weight percent or less. Example 134: The aerosol-generating article of any one of Examples 116-133, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 30 weight percent or less. Example 135: The aerosol-generating article of any one of Examples 116-134, wherein the solid aerosol-generating substrate comprises hydroxypropyl methylcellulose, the solid aerosol-generating substrate having a hydroxypropyl methylcellulose content of 25 weight percent or less. Example 136: The aerosol-generating article of any one of Examples 116-135, wherein the solid aerosol-generating substrate comprises carboxymethyl cellulose, the solid aerosol-generating substrate having a carboxymethyl cellulose content of 2 percent by weight or greater. Example 137: The aerosol-generating article of any one of Examples 116-136, wherein the solid aerosol-generating substrate comprises carboxymethylcellulose, the solid aerosol-generating substrate having a carboxymethylcellulose content of 3 percent by weight or greater. Example 138: The aerosol-generating article of any one of Examples 116-137, wherein the solid aerosol-generating substrate comprises carboxymethyl cellulose, the solid aerosol-generating substrate having a carboxymethyl cellulose content of 4 percent by weight or greater. Example 139: The aerosol-generating article of any one of Examples 116-138, wherein the solid aerosol-generating substrate comprises carboxymethylcellulose, the solid aerosol-generating substrate having a carboxymethylcellulose content of 5 percent by weight or greater. Example 140: The aerosol-generating article of any one of Examples 116-139, wherein the solid aerosol-generating substrate comprises carboxymethyl cellulose, the solid aerosol-generating substrate having a carboxymethyl cellulose content of 12 weight percent or less. Example 141: The aerosol-generating article according to any one of Examples 116-140, wherein the solid aerosol-generating substrate comprises carboxymethylcellulose, the solid aerosol-generating substrate having a carboxymethylcellulose content of 10 weight percent or less. Example 142: The aerosol-generating article according to any one of Examples 116-141, wherein the solid aerosol-generating substrate comprises carboxymethylcellulose, the solid aerosol-generating substrate having a carboxymethylcellulose content of 8 percent by weight or less. Example 143: The aerosol-generating article according to any one of Examples 116-142, wherein the solid aerosol-generating substrate comprises carboxymethylcellulose, the solid aerosol-generating substrate having a carboxymethylcellulose content of 6 percent by weight or less. Example 144: The aerosol-generating article of any one of Examples 116-143, wherein the solid aerosol-generating substrate comprises sodium carboxymethylcellulose. Example 145: An aerosol-generating article according to any one of Examples 1 to 144, wherein the solid aerosol-generating substrate comprises one or more cellulosic binders. Example 146: An aerosol-generating article according to any one of Examples 1 to 145, wherein the solid aerosol-generating substrate comprises one or more cellulosic reinforcing agents. Example 147: The aerosol-generating article according to Example 146, wherein the solid aerosol-generating substrate has a total cellulosic reinforcing agent content of 5 weight percent or greater. Example 148: An aerosol-generating article according to example 146 or 147, wherein the solid aerosol-generating substrate has a total cellulosic reinforcing agent content of 10 weight percent or more. Example 149: The aerosol-generating article of any one of Examples 146-148, wherein the solid aerosol-generating substrate has a total cellulosic reinforcing agent content of 15 weight percent or greater. Example 150: The aerosol-generating article of any one of Examples 146-149, wherein the solid aerosol-generating substrate has a total cellulosic reinforcing agent content of 30 weight percent or less. Example 151: The aerosol-generating article of any one of Examples 146-150, wherein the solid aerosol-generating substrate has a total cellulosic reinforcing agent content of 25 weight percent or less. Example 152: The aerosol-generating article of any one of Examples 146-151, wherein the solid aerosol-generating substrate has a total cellulosic reinforcing agent content of 20 weight percent or less. Example 153: The aerosol-generating article according to any one of Examples 146-152, wherein the solid aerosol-generating substrate comprises one or more cellulosic reinforcing agents selected from cellulose fibers, cellulose powder, and microcrystalline cellulose (MCC). Example 154: The aerosol-generating article of any one of Examples 146 to 153, wherein the solid aerosol-generating substrate comprises cellulose fibers. Example 155: The aerosol-generating article according to example 154, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 0.2 millimeters or more. Example 156: The aerosol-generating article according to embodiment 154 or 155, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 0.5 millimeters or more. Example 157: The aerosol-generating article of any one of Examples 154-156, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 0.7 millimeters or more. Example 158: The aerosol-generating article of any one of Examples 154-157, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 0.9 millimeters or more. Example 159: The aerosol-generating article of any one of Examples 154-158, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 2 millimeters or less. Example 160: The aerosol-generating article of any one of Examples 154-159, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 1.8 millimeters or less. Example 161: The aerosol-generating article of any one of Examples 154-160, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 1.6 millimeters or less. Example 162: The aerosol-generating article of any one of Examples 154-161, wherein the solid aerosol-generating substrate comprises cellulose fibers having a length of 1.4 millimeters or less. Example 163: The aerosol-generating article of any one of Examples 154-162, wherein the solid aerosol-generating substrate has a cellulose fiber content of 2 weight percent or more. Example 164: The aerosol-generating article of any one of Examples 154-163, wherein the solid aerosol-generating substrate has a cellulose fiber content of 5 weight percent or more. Example 165: The aerosol-generating article of any one of Examples 154-164, wherein the solid aerosol-generating substrate has a cellulose fiber content of 10 weight percent or more. Example 166: The aerosol-generating article of any one of Examples 154-165, wherein the solid aerosol-generating substrate has a cellulose fiber content of 15 weight percent or more. Example 167: The aerosol-generating article of any one of Examples 154-166, wherein the solid aerosol-generating substrate has a cellulose fiber content of 30 weight percent or less. Example 168: The aerosol-generating article of any one of Examples 154-167, wherein the solid aerosol-generating substrate has a cellulose fiber content of 25 weight percent or less. Example 169: The aerosol-generating article of any one of Examples 154-168, wherein the solid aerosol-generating substrate has a cellulose fiber content of 20 weight percent or less. Example 170: The aerosol-generating article of any one of Examples 146 to 169, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose. Example 171: The aerosol-generating article according to example 170, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 5 micrometers or more. Example 172: An aerosol-generating article according to example 170 or 171, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 10 micrometers or more. Example 173: The aerosol-generating article of any one of Examples 170 to 172, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 15 micrometers or more. Example 174: The aerosol-generating article of any one of Examples 170 to 173, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 100 micrometers or less. Example 175: The aerosol-generating article of any one of Examples 170 to 174, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 90 micrometers or less. Example 176: The aerosol-generating article of any one of Examples 170 to 175, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 80 micrometers or less. Example 177: The aerosol-generating article of any one of Examples 170-176, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 2 percent by weight or more. Example 178: The aerosol-generating article of any one of Examples 170-177, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 5 weight percent or more. Example 179: The aerosol-generating article of any one of Examples 170-178, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 10 weight percent or more. Example 180: The aerosol-generating article of any one of Examples 170-179, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 15 weight percent or more. Example 181: The aerosol-generating article of any one of Examples 170 to 180, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 30 weight percent or less. Example 182: The aerosol-generating article of any one of Examples 170-181, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 25 weight percent or less. Example 183: The aerosol-generating article of any one of Examples 170-182, wherein the solid aerosol-generating substrate has a microcrystalline cellulose content of 20 weight percent or less. Example 184: The aerosol-generating article of any one of Examples 146 to 183, wherein the solid aerosol-generating substrate comprises cellulose powder. Example 185: The aerosol-generating article according to Example 184, wherein the solid aerosol-generating substrate comprises a cellulose powder having a D50 particle size of 25 micrometers or more. Example 186: An aerosol-generating article according to example 184 or 185, wherein the solid aerosol-generating substrate comprises a cellulose powder having a D50 particle size of 30 micrometers or more. Example 187: The aerosol-generating article of any one of Examples 184 to 186, wherein the solid aerosol-generating substrate comprises a cellulose powder having a D50 particle size of 35 micrometers or more. Example 188: The aerosol-generating article of any one of Examples 184 to 187, wherein the solid aerosol-generating substrate comprises a cellulose powder having a D50 particle size of 250 micrometers or less. Example 189: The aerosol-generating article of any one of Examples 184 to 188, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 225 micrometers or less. Example 190: The aerosol-generating article of any one of Examples 184 to 189, wherein the solid aerosol-generating substrate comprises microcrystalline cellulose having a D50 particle size of 200 micrometers or less. Example 191: The aerosol-generating article of any one of Examples 184-190, wherein the solid aerosol-generating substrate has a cellulose powder content of 2 weight percent or more. Example 192: The aerosol-generating article of any one of Examples 184-191, wherein the solid aerosol-generating substrate has a cellulose powder content of 5 weight percent or more. Example 193: The aerosol-generating article of any one of Examples 184-192, wherein the solid aerosol-generating substrate has a cellulose powder content of 10 weight percent or more. Example 194: The aerosol-generating article of any one of Examples 184-193, wherein the solid aerosol-generating substrate has a cellulose powder content of 15 weight percent or more. Example 195: The aerosol-generating article of any one of Examples 184-194, wherein the solid aerosol-generating substrate has a cellulose powder content of 30 weight percent or less. Example 196: The aerosol-generating article of any one of Examples 184-195, wherein the solid aerosol-generating substrate has a cellulose powder content of 25 weight percent or less. Example 197: The aerosol-generating article of any one of Examples 184-196, wherein the solid aerosol-generating substrate has a cellulose powder content of 20 weight percent or less. Example 198: An aerosol-generating article according to any one of Examples 1 to 197, wherein the solid aerosol-generating substrate comprises water. Example 199: The aerosol-generating article according to example 198, wherein the solid aerosol-generating substrate has a water content of 5 percent by weight or more, based on the total weight of the solid aerosol-generating substrate. Example 200: 199. The aerosol-generating article of embodiment 198 or 199, wherein the solid aerosol-generating substrate has a water content of 10 weight percent or more, based on the total weight of the solid aerosol-generating substrate. Example 201: The aerosol-generating article of any one of Examples 198-200, wherein the solid aerosol-generating substrate has a water content of 15 weight percent or more, based on the total weight of the solid aerosol-generating substrate. Example 202: The aerosol-generating article of any one of Examples 198-201, wherein the solid aerosol-generating substrate has a water content of 17 weight percent or more, based on the total weight of the solid aerosol-generating substrate. Example 203: The aerosol-generating article of any one of Examples 198-202, wherein the solid aerosol-generating substrate has a water content of 35 weight percent or less, based on the total weight of the solid aerosol-generating substrate. Example 204: The aerosol-generating article of any one of Examples 198-203, wherein the solid aerosol-generating substrate has a water content of 30 weight percent or less, based on the total weight of the solid aerosol-generating substrate. Example 205: The aerosol-generating article of any one of Examples 198-204, wherein the solid aerosol-generating substrate has a water content of 25 weight percent or less, based on the total weight of the solid aerosol-generating substrate. Example 206: An aerosol-generating article according to any one of Examples 1 to 205, wherein the solid aerosol-generating substrate comprises one or more non-cellulosic thickeners. Example 207: The aerosol-generating article according to example 206, wherein the solid aerosol-generating substrate comprises one or more non-cellulosic thickeners selected from alginate, gellan gum, guar gum, gum arabic, locust bean gum, pectin, starch, and xanthan gum. Example 208: An aerosol-generating article according to example 206 or 207, wherein the solid aerosol-generating substrate has a total non-cellulosic thickener content of 1 weight percent or greater. Example 209: The aerosol-generating article of any one of Examples 206-208, wherein the solid aerosol-generating substrate has a total non-cellulosic thickener content of 2 weight percent or greater. Example 210: The aerosol-generating article of any one of Examples 206-209, wherein the solid aerosol-generating substrate has a total non-cellulosic thickener content of 3 weight percent or greater. Example 211: The aerosol-generating article of any one of Examples 206-210, wherein the solid aerosol-generating substrate has a total non-cellulosic thickener content of 10 weight percent or less. Example 212: The aerosol-generating article of any one of Examples 206-211, wherein the solid aerosol-generating substrate has a total non-cellulosic thickener content of 8 weight percent or less. Example 213: The aerosol-generating article of any one of Examples 206-212, wherein the solid aerosol-generating substrate has a total non-cellulosic thickener content of 6 weight percent or less. Example 214: An aerosol-generating article according to any one of Examples 1 to 213, wherein the solid aerosol-generating substrate comprises one or more flavourants. Example 215: An aerosol-generating article according to Example 214, wherein the solid aerosol-generating substrate has a total flavorant content of 0.5 weight percent or greater. Example 216: The aerosol-generating article according to Examples 214-215, wherein the solid aerosol-generating substrate has a total flavorant content of 1 weight percent or more. Example 217: The aerosol-generating article of any one of Examples 214-216, wherein the solid aerosol-generating substrate has a total flavorant content of 2 weight percent or more. Example 218: The aerosol-generating article of any one of Examples 214-217, wherein the solid aerosol-generating substrate has a total flavorant content of 3 weight percent or more. Example 219: The aerosol-generating article of any one of Examples 214-218, wherein the solid aerosol-generating substrate has a total flavorant content of 6 weight percent or less. Example 220: The aerosol-generating article of any one of Examples 214-219, wherein the solid aerosol-generating substrate has a total flavorant content of 5 weight percent or less. Example 221: The aerosol-generating article of any one of Examples 214-220, wherein the solid aerosol-generating substrate has a total flavorant content of 4 weight percent or less. Example 222: The aerosol-generating article of any one of Examples 214-221, wherein the solid aerosol-generating substrate has a tobacco content of less than 1 weight percent. Example 223: The aerosol-generating article of any one of Examples 214-222, wherein the solid aerosol-generating substrate has a tobacco content of less than 0.75 weight percent. Example 224: The aerosol-generating article of any one of Examples 214-223, wherein the solid aerosol-generating substrate has a tobacco content of less than 0.5 weight percent. Example 225: The aerosol-generating article of any one of Examples 214-209, wherein the solid aerosol-generating substrate has a tobacco content of less than 0.25 weight percent. Example 226: The aerosol-generating article of any one of Examples 214-210, wherein the solid aerosol-generating substrate has a tobacco content of 0 weight percent. Example 227: An aerosol-generating article according to any one of Examples 1 to 226, wherein the solid aerosol-generating substrate is a solid aerosol-generating film. Example 228: The aerosol-generating article of example 227, wherein the solid aerosol-generating film has a thickness of 0.05 millimeters or more. Example 229: The aerosol-generating article of example 227 or 228, wherein the solid aerosol-generating film has a thickness of 0.1 millimeters or more. Example 230: The aerosol-generating article of any one of Examples 227-229, wherein the solid aerosol-generating film has a thickness of 0.2 millimeters or more. Example 231: The aerosol-generating article of any one of Examples 227-230, wherein the solid aerosol-generating film has a thickness of 0.3 millimeters or more. Example 232: The aerosol-generating article of any one of Examples 227-231, wherein the solid aerosol-generating film has a thickness of 1.2 millimeters or less. Example 233: The aerosol-generating article of any one of Examples 227-232, wherein the solid aerosol-generating film has a thickness of 1 millimeter or less. Example 234: The aerosol-generating article of any one of Examples 227-233, wherein the solid aerosol-generating film has a thickness of 0.8 millimeters or less. Example 235: The aerosol-generating article of any one of Examples 227-234, wherein the solid aerosol-generating film has a thickness of 0.6 millimeters or less. Example 236: The aerosol-generating article of any one of Examples 227-235, wherein the solid aerosol-generating film has a thickness of 0.4 millimeters or less. Example 237: The aerosol-generating article of any one of Examples 227-236, wherein the solid aerosol-generating film has a basis weight of 85 grams per square meter or more. Example 238: The aerosol-generating article of any one of Examples 227-237, wherein the solid aerosol-generating film has a basis weight of 90 grams per square meter or more. Example 239: The aerosol-generating article of any one of Examples 227-238, wherein the solid aerosol-generating film has a basis weight of 100 grams per square meter or more. Example 240: The aerosol-generating article of any one of Examples 227-239, wherein the solid aerosol-generating film has a basis weight of 120 grams per square meter or more. Example 241: The aerosol-generating article of any one of Examples 227-240, wherein the solid aerosol-generating film has a basis weight of 140 grams per square meter or more. Example 242: The aerosol-generating article of any one of Examples 227-241, wherein the solid aerosol-generating film has a basis weight of 300 grams per square meter or less. Example 243: The aerosol-generating article of any one of Examples 227-242, wherein the solid aerosol-generating film has a basis weight of 280 grams per square meter or less. Example 244: The aerosol-generating article of any one of Examples 227-243, wherein the solid aerosol-generating film has a basis weight of 260 grams per square meter or less. Example 245: The aerosol-generating article of any one of Examples 227-244, wherein the solid aerosol-generating film is self-supporting. Example 246: The aerosol-generating article of any one of Examples 227-245, wherein the solid aerosol-generating film is disposed on a substrate. Example 247: The aerosol-generating article of any one of Examples 227-244, wherein the solid aerosol-generating film is disposed on a layered substrate. Example 248: The aerosol-generating article of any one of Examples 227-244, wherein a solid aerosol-generating film is disposed on a sheet material. Example 249: The aerosol-generating article of any one of Examples 227-244, wherein the solid aerosol-generating film is disposed on a paper sheet, an aluminum-coated paper sheet, or a polyethylene-coated paper sheet. Example 250: The aerosol-generating article of any one of Examples 227-244, wherein the solid aerosol-generating film is disposed on a tubular support. Example 251: The aerosol-generating article of any one of Examples 227-244, wherein the solid aerosol-generating film is disposed on an inner surface of a hollow tubular support. Example 252: The aerosol-generating article of any one of Examples 227-251, wherein the aerosol-generating article comprises an aerosol-generating rod including a solid aerosol-generating film, the solid aerosol-generating film being cut or otherwise divided into a plurality of strips or pieces that are rolled together to form the aerosol-generating rod. Example 253: The aerosol-generating article according to any one of Examples 227 to 251, wherein the aerosol-generating article comprises an aerosol-generating rod comprising a solid aerosol-generating film, the solid aerosol-generating films collectively forming the aerosol-generating rod. Example 254: The aerosol-generating article according to Example 253, wherein the solid aerosol-generating film is textured. Example 255: The aerosol-generating article according to Example 253, wherein the solid aerosol-generating film is crimped. Example 256: An aerosol-generating article according to any one of Examples 1 to 255, wherein the aerosol-generating article comprises an aerosol-generating rod comprising a solid aerosol-generating substrate. Example 257: An aerosol-generating article according to any one of Examples 1 to 256, comprising a susceptor in direct contact with a solid aerosol-generating substrate. Example 258: The aerosol-generating article according to Example 257, wherein the aerosol-generating article comprises an aerosol-generating rod comprising a solid aerosol-generating substrate, and the susceptor is located within the aerosol-generating rod comprising the solid aerosol-generating substrate. Example 259: The aerosol-generating article according to example 257 or 258, wherein the susceptor is located within the solid aerosol-generating substrate. Example 260: The aerosol-generating article of any one of Examples 257-259, wherein the solid aerosol-generating substrate at least partially surrounds the susceptor. Example 261: The aerosol-generating article of any one of Examples 257-259, wherein the solid aerosol-generating substrate is disposed on a susceptor. Example 262: The aerosol-generating article of any one of Examples 257-259, wherein the solid aerosol-generating substrate is a solid aerosol-generating film and the susceptor is at least partially coated with the solid aerosol-generating film. Example 263: The aerosol-generating article of any one of Examples 257-259, wherein the solid aerosol-generating substrate is at least partially embedded within the solid aerosol-generating substrate. Example 264: The aerosol-generating article of any one of Examples 257-259, wherein the solid aerosol-generating substrate is a solid aerosol-generating gel and the susceptor is at least partially embedded within the solid aerosol-generating gel. Example 265: An aerosol-generating article according to any one of Examples 257 to 264, wherein the susceptor is elongated. Example 266: The aerosol-generating article of any one of Examples 257-265, wherein the susceptor extends along a longitudinal axis of the aerosol-generating article. Example 267: The aerosol-generating article of any one of Examples 257-266, wherein the susceptor has a length of 6 millimeters to 18 millimeters. Example 268: The aerosol-generating article of any one of Examples 257-267, wherein the susceptor has a length of 8 millimeters to 16 millimeters. Example 269: The aerosol-generating article of any one of Examples 257-268, wherein the susceptor has a length of 10 millimeters to 14 millimeters. Example 270: The aerosol-generating article of any one of Examples 257-269, wherein the susceptor has a width of 2 millimeters to 8 millimeters. Example 271: The aerosol-generating article of any one of Examples 257-270, wherein the susceptor has a width of 3 millimeters to 7 millimeters. Example 272: The aerosol-generating article of any one of Examples 257-271, wherein the susceptor has a width of 4 millimeters to 6 millimeters. Example 273: The aerosol-generating article of any one of Examples 257-272, wherein the susceptor has a thickness of 30 micrometers to 90 micrometers. Example 274: The aerosol-generating article of any one of Examples 257-273, wherein the susceptor has a thickness of 40 micrometers to 80 micrometers. Example 275: The aerosol-generating article of any one of Examples 257-274, wherein the susceptor has a thickness of 50 micrometers to 70 micrometers. Example 276: The aerosol-generating article according to any one of Examples 1-275, wherein the aerosol-generating article comprises an upstream element located at a distal end of the aerosol-generating article. Example 277: The aerosol-generating article according to Example 276, wherein the upstream element is located immediately upstream of the solid aerosol-generating substrate. Example 278: The aerosol-generating article according to example 276 or 277, wherein the upstream element comprises a plug of porous material. Example 279: The aerosol-generating article according to any one of Examples 276-278, wherein the upstream element comprises a cellulose acetate plug. Example 280: The aerosol-generating article according to any one of Examples 1-279, wherein the aerosol-generating article comprises a support element located between the solid aerosol-generating substrate and a proximal end of the aerosol-generating article. Example 281: The aerosol-generating article according to Example 280, wherein the support element is located immediately downstream of the solid aerosol-generating substrate. Example 282: The aerosol-generating article according to example 280 or 281, wherein the support element comprises a hollow tubular segment. Example 283: The aerosol-generating article of any one of Examples 280-282, wherein the hollow tubular segment defines a longitudinal cavity providing an unrestricted flow channel. Example 284: The aerosol-generating article of any one of Examples 280-283, wherein the support element comprises a hollow cellulose acetate tube. Example 285: An aerosol-generating article according to any one of Examples 1 to 284, wherein the aerosol-generating article comprises a mouthpiece element located at a proximal end of the aerosol-generating article. Example 286: The aerosol-generating article according to example 285, wherein the mouthpiece element comprises a plug of porous material. Example 287: The aerosol-generating article according to example 285 or 286, wherein the mouthpiece element comprises a cellulose acetate plug. Example 288: The aerosol-generating article of any one of Examples 285-287, wherein the mouthpiece element includes a cavity at the mouth end. Example 289: The aerosol-generating article according to Example 288, wherein the cavity at the oral end is defined by a hollow tubular element provided at the proximal end of the mouthpiece element. Example 290: The aerosol-generating article of example 288, wherein the cavity at the mouth end is defined by a wrapper. Example 291: The aerosol-generating article according to any one of Examples 1-290, wherein the aerosol-generating article comprises an aerosol cooling element located between the solid aerosol-generating substrate and the proximal end of the aerosol-generating article. Example 292: An aerosol-generating article according to Example 291, wherein the aerosol-generating article comprises a mouthpiece, and the aerosol cooling element is located immediately upstream of the mouthpiece element. Example 293: The aerosol-generating article according to embodiment 291 or 292, wherein the aerosol-generating article comprises a support element, and the aerosol cooling element is located immediately downstream of the support element. Example 294: The aerosol-generating article of any one of Examples 291-293, wherein the aerosol cooling element comprises a hollow tubular segment. Example 295: The aerosol-generating article of any one of Examples 291-294, wherein the hollow tubular segment defines a longitudinal cavity providing an unrestricted flow channel. Example 296: The aerosol-generating article of any one of Examples 291-295, wherein the aerosol cooling element comprises a hollow cellulose acetate tube. Example 297: An aerosol-generating article according to any one of Examples 1 to 296, wherein the aerosol-generating article comprises a ventilation zone located between the solid aerosol-generating substrate and the proximal end of the aerosol-generating article. Example 298: The aerosol-generating article according to Example 297, wherein the aerosol-generating article comprises an aerosol cooling element, and a ventilation zone is provided at a location along the aerosol cooling element. Example 299: The aerosol-generating article of embodiment 297 or 298, wherein the aerosol-generating article has a breathability level of 10 percent or greater. Example 300: The aerosol-generating article of any one of Examples 297-299, wherein the aerosol-generating article has a breathability level of 15 percent or greater. Example 301: The aerosol-generating article of any one of Examples 297-300, wherein the aerosol-generating article has a breathability level of 20 percent or more. Example 302: The aerosol-generating article of any one of Examples 297-301, wherein the aerosol-generating article has a breathability level of 25 percent or more. Example 303: The aerosol-generating article of any one of Examples 297-302, wherein the aerosol-generating article has a breathability level of 50 percent or less. Example 304: The aerosol-generating article of any one of Examples 297-303, wherein the aerosol-generating article has a breathability level of 45 percent or less. Example 305: The aerosol-generating article of any one of Examples 297-304, wherein the aerosol-generating article has a breathability level of 40 percent or less. Example 306: An aerosol generating system comprising an aerosol-generating article according to any one of Examples 1-305 and an aerosol generating apparatus configured to heat the solid aerosol-generating substrate of the aerosol-generating article. Example 307: An aerosol generating system comprising an aerosol-generating article according to any one of Examples 1-305 and an electrically actuated aerosol generating device configured to heat the solid aerosol-generating substrate of the aerosol-generating article. Example 308: An aerosol generating system comprising an aerosol generating article according to any one of Examples 1 to 305 and an electrically operated aerosol generating device including an inductor configured to heat a solid aerosol generating substrate of the aerosol generating article. Example 309: The aerosol generating system according to any one of Examples 306-308, wherein the aerosol generating device comprises a housing defining a cavity of the device configured to receive at least a portion of the aerosol generating article. Example 310: The aerosol generating system according to any one of Examples 306 to 309, wherein the aerosol generating device is a handheld aerosol generating device. Example 311: An aerosol generation system according to any one of Examples 306 to 310, wherein the aerosol generation device comprises a power source and control electronics. Example 312: An aerosol generating system according to any one of Examples 306 to 311, wherein the aerosol generating device comprises a battery and control electronics. Example 313: An aerosol generation system according to any one of Examples 306 to 311, wherein the aerosol generation device comprises an inductor including one or more induction coils.

[0407] The invention will now be described, by way of example only, with reference to the following examples and the accompanying drawings. [Brief description of the drawings]

[0408] [Figure 1] FIG. 1 is a schematic cross-sectional view of one embodiment of an aerosol-generating article according to a first aspect of the invention, comprising a solid aerosol-generating substrate and a susceptor. [Diagram 2] FIG. 2 is a schematic cross-sectional view of one embodiment of an aerosol generation system according to a second aspect of the invention, comprising the aerosol generating article shown in FIG. 1 and an electrically operated aerosol generating device including an inductor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0409] The aerosol-generating article 10 shown in Figure 1 comprises an aerosol-generating rod 12, a proximal section 14 located downstream of the aerosol-generating rod 12, and a distal section 16 located upstream of the aerosol-generating rod 12. As shown in Figure 1, the aerosol-generating article 10 has an upstream or distal end 18 and a downstream or proximal end 20. The aerosol-generating article 10 may have an overall length of 45 millimeters and an outer diameter of 7.2 millimeters.

[0410] The proximal section 14 of the aerosol-generating article 10 includes a support element 22 located immediately downstream of the aerosol-generating rod 12, an aerosol cooling element 24 located immediately downstream of the support element 22, and a mouthpiece element 42 located immediately downstream of the aerosol cooling element 24. Together, the support element 22 and the aerosol cooling element 24 define an intermediate hollow section 50 of the aerosol-generating article 10.

[0411] The support element 22 may include a first hollow tubular segment 26. The first hollow tubular segment 26 is in the form of a hollow cylindrical tube made of cellulose acetate. The first hollow tubular segment 26 defines an interior cavity 28 extending from an upstream end 30 of the first hollow tubular segment to a downstream end 32 of the first hollow tubular segment 20. The first hollow tubular segment 26 may have a length of 8 millimeters and an outer diameter of 6.9 millimeters. The first hollow tubular segment 26 may have an inner diameter of 1.9 millimeters.

[0412] The aerosol cooling element 24 includes a second hollow tubular segment 34. The second hollow tubular segment 34 is in the form of a hollow cylindrical tube made of cellulose acetate. The second hollow tubular segment 34 defines an interior cavity 36 extending from an upstream end 38 of the second hollow tubular segment to a downstream end 40 of the second hollow tubular segment 34. The second hollow tubular segment 34 may have a length of 13 millimeters and an outer diameter of 6.9 millimeters. The second hollow tubular segment 34 may have an inner diameter of 3.25 millimeters.

[0413] 1, the aerosol-generating article 10 includes a ventilation zone 60 provided at a location along the second hollow tubular segment 34. The ventilation zone may be provided 2 millimeters from the upstream end of the second hollow tubular segment 34. The ventilation level of the aerosol-generating article 10 may be 35 percent.

[0414] The mouthpiece element 42 is in the form of a cylindrical plug of low density cellulose acetate. The mouthpiece element 42 may have a length of 7 millimeters and an outer diameter of 6.9 millimeters.

[0415] The aerosol-generating rod 12 comprises an assembly of crimped paper sheets coated with a solid aerosol-generating film having the composition shown in Example A. The aerosol-generating rod 12 may have a length of 12 millimeters and an outer diameter of 6.9 millimeters.

[0416] The aerosol-generating article 10 comprises an elongated susceptor 44 located within the aerosol-generating rod 12. As shown in Figure 2, the elongated susceptor 44 is surrounded by a collection of crimped paper sheets covered with a solid aerosol-generating film and extends along the longitudinal axis of the aerosol-generating rod 12 from the upstream end of the aerosol-generating rod 12 to the downstream end of the aerosol-generating rod 12. The elongated susceptor 44 is in direct contact with the solid aerosol-generating film. The elongated susceptor 44 may be in the form of a strip having a length of 12 millimeters, a width of 5 millimeters, and a thickness of 60 micrometers.

[0417] The distal section 16 of the aerosol-generating article 10 includes an upstream element 46 located immediately upstream of the aerosol-generating rod 12 .

[0418] The upstream element 46 is in the form of a cylindrical plug of cellulose acetate surrounded by a rigid wrapper. The upstream element 46 may have a length of 5 millimeters and an outer diameter of 6.9 millimeters.

[0419] It will be appreciated that the aerosol-generating article 10 shown in FIG. 1 is merely one example of one embodiment of an aerosol-generating article according to the first aspect of the invention and that other embodiments are possible.

[0420] The aerosol generating system 100 shown in FIG. 2 comprises the aerosol generating article 10 shown in FIG.

[0421] The aerosol generating device 110 comprises a housing 112 defining a device cavity 114 configured to receive a distal portion of the aerosol generating article 10 .

[0422] The aerosol generating device 110 includes an inductor 116 configured to heat a solid aerosol-generating film within the aerosol-generating rod 12 of the aerosol-generating article 10 when a distal portion of the aerosol-generating article 10 is received within a cavity 114 of the device.

[0423] The aerosol generating device also includes a power source (not shown) in the form of a battery, such as a rechargeable lithium ion battery, and control circuitry (not shown).

[0424] The inductor 116 includes an induction coil. The control circuit controls the supply of power from the battery to the induction coil.

[0425] In use, the varying or alternating electromagnetic field generated by the induction coil of the inductor 116 induces eddy currents in the elongated susceptor 44 in the aerosol-generating rod 12 of the aerosol-generating article 10, heating the elongated susceptor 44. The heat generated in the elongated susceptor 44 is transferred by conduction to the solid aerosol-generating film in the aerosol-generating rod 12 of the aerosol-generating article 10.

[0426] A user inhales on the mouthpiece element 42 of the aerosol-generating article 10. As the user inhales on the mouthpiece 142, air is drawn into the aerosol-generating article 10 via the distal end 18. The drawn-in air passes through the upstream element 46 to the aerosol-generating rod 12. Heating of the solid aerosol-generating film releases volatile and semi-volatile compounds, which form an aerosol that is entrained in the drawn-in air as it flows through the aerosol-generating rod 12. The drawn-in air and entrained aerosol pass through the intermediate hollow section 50 of the aerosol-generating article 10, where it cools and condenses. The cooled aerosol then passes downstream through the mouthpiece element 42 of the aerosol-generating article 10 into the user's mouth.

[0427] Working Example Solid Aerosol Generating Films - Examples A to G Solid aerosol-generating films for use in aerosol-generating articles according to the first aspect of the present invention are prepared having the compositions set out in Examples A-G below.

[0428] The solid aerosol-generating films of Examples A to G are (1) mixing the components with water by stirring to form a slurry; (2) casting a layer of the slurry on a flat surface to form a film having a thickness of 600 to 1000 micrometers; (3) leaving the film on a flat surface to solidify; (4) drying the film by heating the film to 140 degrees Celsius for 8 minutes to form a solid aerosol-generating film. [Table 1] [Table 2] [Table 3] [Table 4] [Table 5] [Table 6] [Table 7]

[0429] The solid aerosol-generating films prepared in Examples A-G are heated to a temperature of 250° C.-260° C. to simulate the conditions of use in an aerosol-generating system according to the second embodiment of the present invention. The nicotine and glycerin in the solid aerosol-generating films evaporate and condense to form an inhalable aerosol. The solid aerosol-generating film shrinks slightly, decreasing its volume. However, the solid aerosol-generating film remains solid.

[0430] Aerosol-Generating Articles - Examples 1 to 6 and Comparative Examples 7 and 8 An aerosol-generating rod for use in an aerosol-generating article according to the first embodiment of the present invention having the structure shown in FIG. 1 is prepared comprising an assembly of crimped paper sheets coated with a solid aerosol-generating film having the composition shown in Examples A to C.

[0431] A comparative aerosol-generating rod for use with an aerosol-generating article not according to the invention having the structure shown in FIG. 1 was prepared comprising an assembly of crimped paper sheets coated with a solid aerosol-generating film having the composition shown in the Comparative Example below. [Table 8]

[0432] The aerosol-generating rod and the comparative aerosol-generating rod each had a length of 12 millimeters and an outer diameter of 6.9 millimeters.

[0433] Each of the aerosol-generating rods and the comparative aerosol-generating rods includes an elongated susceptor in the form of a strip having a length of 12 millimeters, a width of 5 millimeters, and a thickness of 60 micrometers extending along the longitudinal axis of the aerosol-generating rod. The elongated susceptor is in direct contact with the solid aerosol-generating film and consists of a layer of AK Steel 430 having a thickness of 3.5 micrometers, a layer of PHYTHERM 260 (Ni-Fe-Cr alloy) supplied by Aperam having a thickness of 14 micrometers, and a layer of AK Steel 430 having a thickness of 42.5 micrometers.

[0434] The susceptors in the aerosol-generating rods and the comparative aerosol-generating rods were measured using energy dispersive X-ray spectroscopy (EDX) and by visual inspection using a scanning electron microscope (SEM) to determine the as-manufactured (T 0 ), 7 days after production (T 1 ), and 7 weeks after manufacture (T 2 ) are evaluated for signs of corrosion (e.g., oxidation or pitting of the surface of the susceptor). The results are shown in Table 1 below. 0 , T 1 and T 2 The value indicates the number of aerosol-generating rods whose susceptors show signs of corrosion, as well as the total number of aerosol-generating rods whose susceptors were evaluated for signs of corrosion for each of the examples and comparative examples. For example, 7 / 10 means that out of a total of 10 aerosol-generating rods whose susceptors were evaluated for signs of corrosion, there were 7 aerosol-generating rods whose susceptors showed signs of corrosion. [Table 9]

[0435] As shown in Table 1, in the aerosol-generating rods of Comparative Examples 7 and 8, which contained a solid aerosol-generating film containing lactic acid, most of the susceptors were destroyed 7 days after manufacture (T 1 ) and 7 weeks after manufacture (T 2 ) shows signs of corrosion.

[0436] In contrast, for the aerosol-generating rods of Examples 5 and 6 containing malic acid, only a small percentage of the susceptors remained after 7 days of manufacture (T 1 ) and the susceptors showed signs of corrosion 7 days after manufacture (T 1 ) or 7 weeks after manufacture (T 2 ) shows no signs of corrosion.

[0437] The specific embodiments and examples described above are illustrative of the invention but do not limit it, it being understood that other embodiments of the invention may be made and that the specific embodiments and examples described herein are not exhaustive.

[0438] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing amounts, quantities, percentages, and the like should be understood in all cases as being modified by the term "about." Thus, in this context, the number A is understood as A±10% of A. Within this context, the number A may be considered to include values ​​that are within the typical standard error for the measurement of the property that the number A modifies. The number A may deviate by the percentages recited above, provided that in some cases used in the appended claims, the amount by which A deviates does not materially affect the basic and novel properties of the claimed invention. Additionally, all ranges include the maximum and minimum points disclosed, and include any intermediate ranges therein, which may or may not be specifically recited herein.

Claims

1. 1. An aerosol-generating article for use in an aerosol-generating system, said aerosol-generating article comprising: a solid aerosol-generating substrate comprising nicotine, one or more cellulosic agents, one or more aerosol formers, and one or more carboxylic acids (i) that contain no non-carboxyl alkyl hydroxyl groups and no ketone groups, or (ii) that have a pKa in water of 3.5 or less at 25°C, or (iii) that contain no non-carboxyl alkyl hydroxyl groups, no ketone groups, and that have a pKa in water of 3.5 or less at 25°C; a susceptor in direct contact with the solid aerosol-generating substrate; An aerosol-generating article wherein the solid aerosol-generating substrate has a total cellulosic agent content of at least 35 weight percent, a total aerosol former content of 45 weight percent or more, and a total carboxylic acid content of at least 0.5 weight percent.

2. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, malic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid.

3. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from acetic acid, adipic acid, benzoic acid, citric acid, fumaric acid, maleic acid, myristic acid, oxalic acid, salicylic acid, stearic acid, succinic acid, and undecanoic acid.

4. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, maleic acid, and malic acid.

5. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from acetic acid, benzoic acid, citric acid, fumaric acid, and maleic acid.

6. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from fumaric acid, maleic acid, and malic acid.

7. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more carboxylic acids selected from fumaric acid and maleic acid.

8. 2. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises fumaric acid.

9. 9. The aerosol-generating article according to claim 8, wherein the molar ratio of fumaric acid to nicotine in the solid aerosol-generating substrate is from 0.5:1 to 4:

1.

10. 10. The aerosol-generating article according to claim 1, wherein the solid aerosol-generating substrate does not contain iota-carrageenan or kappa-carrageenan.

11. 10. The aerosol-generating article according to claim 1, wherein the solid aerosol-generating substrate further comprises one or more carboxylic acids selected from lactic acid and levulinic acid.

12. 10. The aerosol-generating article of any one of claims 1 to 9, wherein the solid aerosol-generating substrate has a total carboxylic acid content of from 1 weight percent to 6 weight percent.

13. 10. The aerosol-generating article according to claim 1, wherein the molar ratio of total carboxylic acid to nicotine in the solid aerosol-generating substrate is from 0.5:1 to 5:

1.

14. 10. The aerosol-generating article of any one of claims 1 to 9, wherein the solid aerosol-generating substrate has a total cellulosic agent content of from 35 percent to 50 percent by weight.

15. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more cellulosic film-forming agents selected from carboxymethyl cellulose and hydroxypropyl methyl cellulose.

16. 10. The aerosol-generating article of claim 1, wherein the solid aerosol-generating substrate comprises one or more cellulosic reinforcing agents selected from cellulose fibers, microcrystalline cellulose, and cellulose powder.

17. 10. An aerosol-generating article according to any one of claims 1 to 9, wherein the solid aerosol-generating substrate at least partially surrounds a susceptor.

18. 10. The aerosol-generating article according to claim 1, wherein the solid aerosol-generating substrate is a solid aerosol-generating film.

19. 10. An aerosol-generating article according to any one of claims 1 to 9, wherein the solid aerosol-generating substrate remains solid when heated to a temperature of from 180 degrees Celsius to 350 degrees Celsius.

20. 1. An aerosol generating system comprising: An aerosol-generating article according to any one of claims 1 to 9; an electrically powered aerosol generating device including an inductor configured to heat a solid aerosol-generating substrate of the aerosol-generating article.

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