Novel aerosol-generating substrates containing Matricaria species

Abstract

The heated aerosol-generating article (1000), (4000a, 4000b), or (5000) includes an aerosol-generating substrate (1020), which is formed from a homogenized chamomile material containing chamomile particles, an aerosol former, and a binder. The aerosol-generating substrate may further include at least 20 micrograms of bisabolol oxide A per gram of substrate, on a dry weight basis, at least 100 micrograms of Tonghuas isomer per gram of substrate, on a dry weight basis, and at least 15 micrograms of α-bisabolol per gram of substrate, on a dry weight basis.

Description

[Technical Field]

[0001] The present invention relates to aerosol-generating substrates comprising homogenized plant material formed from chamomile particles, and to aerosol-generating articles incorporating such aerosol-generating substrates. The present invention further relates to aerosols derived from aerosol-generating substrates comprising chamomile particles. [Background technology]

[0002] Heated aerosol-generating articles, in which an aerosol-generating substrate, such as a tobacco-containing substrate, is heated rather than combusted (also known as non-combustion heated articles), are known in the art. Typically, in such articles, the aerosol is generated by transferring heat from a heat source to a physically separate aerosol-generating substrate or material, which may be located in contact with, within, around, or downstream of the heat source. During use of the aerosol-generating article, volatile compounds are released from the substrate by heat transfer from the heat source and become entrained in the air drawn through the article. Upon cooling, the released compounds condense to form an aerosol.

[0003] Some aerosol-generating articles comprise flavorings that are delivered to the consumer during use of the article to provide a different sensory experience to the consumer, for example, to enhance the flavor of the aerosol. Flavorings can be used to deliver a taste (flavor), an odor (smell), or both taste and odor to the user inhaling the aerosol. It is known to provide heated aerosol-generating articles that include flavorings.

[0004] It is also known to provide flavorants to conventional combustible cigarettes, which are smoked by lighting the end of the cigarette opposite the mouthpiece so that the tobacco rod burns, generating inhalable smoke. Typically, one or more flavorants are mixed with the tobacco in the tobacco rod to provide additional flavor to the mainstream smoke as the tobacco is burned. Such flavorants may be provided, for example, as essential oils.

[0005] Aerosol from conventional cigarettes contains many components that interact with receptors located in the mouth, providing a sensation of "body," or a relatively strong mouthfeel. "Mouthfeel," as used herein, refers to the physical sensation in the mouth caused by a food, beverage, or aerosol, and is distinct from taste. Mouthfeel, along with taste and odor, is a fundamental sensory attribute that determines the overall flavor of a food or aerosol.

[0006] Reproducing the consumer experience provided by traditional combustible cigarettes with aerosol-generating articles in which the aerosol-generating substrate is heated rather than combusted is difficult, in part because of the lower temperatures reached during heating of such aerosol-generating articles, which result in the release of a different profile of volatile compounds.

[0007] It would be desirable to provide novel aerosol-generating substrates for heated aerosol-generating articles that provide aerosols with improved flavor and body. Such aerosol-generating substrates would be particularly desirable if they could provide aerosols with a sensory experience comparable to that provided by conventional combustible cigarettes. Furthermore, such aerosol-generating substrates would be particularly desirable if they could provide aerosols with reduced levels of undesirable aerosol compounds compared to existing aerosol-generating substrates, such as those containing only tobacco.

[0008] It would be further desirable to provide such an aerosol-generating substrate that can be easily incorporated into an aerosol-generating article and that can be manufactured using existing rapid methods and equipment. Summary of the Invention

[0009] The present disclosure relates to an aerosol-generating article including an aerosol-generating substrate, the aerosol-generating substrate being formed from a homogenized plant material containing chamomile particles, referred to herein as a "homogenized chamomile material." The homogenized chamomile material may further include an aerosol former. The homogenized chamomile material may further include a binder. The aerosol-generating substrate may further include, on a dry weight basis, at least about 20 micrograms of bisabolol oxide A per gram of substrate. The aerosol-generating substrate may further include, on a dry weight basis, at least about 100 micrograms of Tonghaos isomer per gram of substrate. The aerosol-generating substrate may further include, on a dry weight basis, at least about 15 micrograms of α-bisabolol per gram of substrate.

[0010] The present invention provides an aerosol-generating article comprising an aerosol-generating substrate, the aerosol-generating substrate being formed from a homogenized chamomile material containing chamomile particles. The homogenized chamomile material comprises chamomile particles, an aerosol former, and a binder. The aerosol-generating substrate may further comprise, on a dry weight basis, at least about 20 micrograms of bisabolol oxide A per gram of substrate, at least about 100 micrograms of Tonghaos isomer per gram of substrate, and at least about 15 micrograms of α-bisabolol per gram of substrate.

[0011] Upon heating the aerosol-generating substrate of an aerosol-generating article according to the present invention by Test Method A described below, an aerosol is preferably generated that contains at least about 5 micrograms of bisabolol oxide A per gram of substrate, on a dry weight basis; at least about 5 micrograms of Tonghaos isomer per gram of substrate, on a dry weight basis; and at least about 3 micrograms of α-bisabolol per gram of substrate, on a dry weight basis.

[0012] Preferably, upon heating the aerosol-generating substrate according to Test Method A, the aerosol generated from the aerosol-generating substrate may contain bisabolol oxide A in an amount of at least about 0.1 micrograms per aerosol puff. Upon heating the aerosol-generating substrate according to Test Method A, the aerosol generated from the aerosol-generating substrate may contain Tonghaos isomer in an amount of at least 0.1 micrograms per aerosol puff. Upon heating the aerosol-generating substrate according to Test Method A, the aerosol generated from the aerosol-generating substrate may contain α-bisabolol in an amount of at least about 0.05 micrograms per aerosol puff. The aerosol puff has a volume of 55 milliliters when generated by the smoking machine.

[0013] According to the present invention, there is provided an aerosol-generating article comprising an aerosol-generating substrate formed from a homogenized chamomile material containing chamomile particles. The aerosol-generating substrate may contain, on a dry weight basis, at least about 20 micrograms of bisabolol oxide A per gram of substrate, at least about 100 micrograms of Tonghaos isomer per gram of substrate, and at least about 15 micrograms of α-bisabolol per gram of substrate.

[0014] The present disclosure also relates to an aerosol-generating substrate formed from homogenized plant material containing chamomile particles, referred to herein as "homogenized chamomile material." The homogenized chamomile material may further comprise an aerosol former. The homogenized plant material may further comprise a binder. The aerosol-generating substrate may contain, on a dry weight basis, at least about 20 micrograms of bisabolol oxide A per gram of substrate. The aerosol-generating substrate may contain, on a dry weight basis, at least about 100 micrograms of Tonghaos isomer per gram of substrate. The aerosol-generating substrate may contain, on a dry weight basis, at least about 15 micrograms of α-bisabolol per gram of substrate.

[0015] The present invention also provides an aerosol-generating substrate formed from homogenized chamomile material, wherein the homogenized chamomile material comprises chamomile particles, an aerosol former, and a binder. The aerosol-generating substrate may further comprise, on a dry weight basis, at least 20 micrograms of bisabolol oxide A per gram of substrate, at least 100 micrograms of Tonghaos isomer per gram of substrate, and at least 15 micrograms of α-bisabolol per gram of substrate.

[0016] The present disclosure also relates to an aerosol generated upon heating of an aerosol-generating substrate. The aerosol may contain bisabolol oxide A in an amount of at least about 0.1 micrograms per aerosol puff. The aerosol may contain Tonghaos isomer in an amount of at least about 0.1 micrograms per aerosol puff. The aerosol may contain α-bisabolol in an amount of at least about 0.05 micrograms per aerosol puff. The aerosol puff has a volume of 55 milliliters when generated by a smoking machine.

[0017] The present invention further provides an aerosol produced upon heating of an aerosol-generating substrate, the aerosol comprising bisabolol oxide A in an amount of at least 0.1 micrograms per aerosol puff, Tonghaos isomer in an amount of at least 0.1 micrograms per aerosol puff, and α-bisabolol in an amount of at least 0.05 micrograms per aerosol puff, the aerosol puff having a volume of 55 milliliters when generated by a smoking machine.

[0018] The present invention further provides a method of making an aerosol-generating substrate, comprising forming a slurry containing chamomile particles, water, an aerosol former, a binder, and optionally tobacco particles, casting or extruding the slurry in the form of a sheet or strand, and drying the sheet or strand, preferably at a temperature of from 80° C. to 160° C. If a sheet of the aerosol-generating substrate is formed, the sheet may optionally be cut into strands or assembled to form a rod. The sheet may optionally be crimped prior to the assembly step.

[0019] The following references to the aerosol-generating substrates and aerosols of the present invention are considered to be applicable to all aspects of the invention unless otherwise indicated.

[0020] As used herein, the term "aerosol-generating article" refers to an article for producing an aerosol, where the article comprises an aerosol-generating substrate that is suitable and intended to be heated or burned to release volatile compounds capable of forming an aerosol. A conventional cigarette is lit when a user applies a flame to one end of the cigarette and draws air through the other end. Localized heat provided by the flame and the oxygen in the air drawn through the cigarette ignites the end of the cigarette, and the resulting combustion produces inhalable smoke. In contrast, in a "heated aerosol-generating article," the aerosol is generated by heating the aerosol-generating substrate rather than by burning it. Known heated aerosol-generating articles include, for example, electrically heated aerosol-generating articles and aerosol-generating articles in which the aerosol is generated by transferring heat from a combustible fuel element or heat source to a physically separated aerosol-generating substrate.

[0021] Also known are aerosol-generating articles adapted for use in aerosol-generating systems that supply aerosol formers to the aerosol-generating article, where the aerosol-generating substrate in the aerosol-generating article contains substantially less aerosol formers relative to the aerosol-generating substrate that carries and provides substantially all of the aerosol formers used to form the aerosol during operation.

[0022] As used herein, the term "aerosol-generating substrate" refers to a substrate capable of generating, upon heating, volatile compounds capable of forming an aerosol. The aerosol generated from an aerosol-generating substrate may or may not be visible to the human eye and may include vapor (e.g., gaseous fine particles of a substance that is normally a liquid or solid at room temperature) as well as gas and liquid droplets of condensed vapor.

[0023] As used herein, the term "homogenized plant material" encompasses any plant material formed by agglomeration of plant particles. For example, a sheet or web of homogenized plant material for an aerosol-generating substrate of the present invention may be formed by agglomerating particles of chamomile plant material and, optionally, plant material obtained by grinding, milling, or comminuting tobacco material, such as tobacco blades or stems. Homogenized plant material may be produced by casting, extrusion, a papermaking process, or any other suitable process known in the art.

[0024] As used herein, the term "homogenized chamomile material" refers to a homogenized plant material containing chamomile particles, optionally in combination with tobacco particles. The term "homogenized tobacco material" refers to a homogenized plant material containing tobacco particles but not containing chamomile particles, and is therefore not in accordance with the present invention.

[0025] As used herein, the term "chamomile particles" includes particles derived from chamomile flowers. In the present invention, German chamomile, Matricaria chamomilla L. flowers, are preferably used. Matricaria chamomilla L. is a flowering plant of the Matricaria species with daisy-like flowers, belonging to the Asteraceae family. The plant is native to Southern and Eastern Europe.

[0026] Dried chamomile flowers are commonly used to make herbal infusions or teas, and chamomile extracts are used in skin care products such as soaps, shampoos, and skin creams, as well as in condiments and beverages.

[0027] In contrast, chamomile essential oil is a distillate, and bisabolol and tonghaos isomers are compounds derived from chamomile.

[0028] The present invention provides an aerosol-generating article incorporating an aerosol-generating substrate formed of homogenized plant material containing chamomile particles, referred to herein as homogenized chamomile material. The present invention also provides an aerosol derived from such an aerosol-generating substrate. The inventors have found that by incorporating chamomile particles into an aerosol-generating substrate, it is advantageously possible to produce an aerosol that provides a novel sensory experience. Such an aerosol may provide a unique flavor and an increased level of body.

[0029] Furthermore, the inventors have found that it is possible to produce an aerosol with an improved chamomile fragrance and flavor, advantageously compared to aerosols produced by the addition of chamomile additives such as chamomile oil. Chamomile oil (Chemical Abstracts Service Registration No. 8002-66-2) is obtained by steam distillation from the flower buds and peduncles of chamomile plants and has a different flavor composition than chamomile particles, which is believed to be due to the distillation process, which may selectively remove or retain certain flavors. Bisabolol and bisabolol derivatives are some of the major components of chamomile oil, and bisabolol, in particular, accounts for up to 33 percent of chamomile oil.

[0030] Furthermore, in certain aerosol-generating substrates provided herein, chamomile particles are incorporated at a level sufficient to provide a desirable chamomile flavor, while maintaining sufficient tobacco material to provide a desirable level of nicotine to the consumer.

[0031] Furthermore, it has been surprisingly found that the inclusion of chamomile particles in an aerosol-generating substrate provides a significant reduction in certain undesirable aerosol compounds compared to aerosols generated from an aerosol-generating substrate containing 100 percent tobacco particles but without chamomile particles. In particular, as described below, it has been surprisingly found that the inclusion of chamomile particles in an aerosol-generating substrate provides a significant reduction in polycyclic aromatic hydrocarbons (PAHs) compared to aerosols generated from an aerosol-generating substrate containing 100 percent tobacco particles but without chamomile particles. Furthermore, this reduction has been found to be greater than would be proportionally expected as a result of the reduction in tobacco particles.

[0032] The presence of chamomile in homogenized plant material (such as cast leaves) can be reliably identified by DNA barcoding. Methods for performing DNA barcoding based on the nuclear genes ITS2, rbcL, and matK, and the plastid intergenic spacer trnH-psbA are known in the art and can be used (Chen S, Yao H, Han J, Liu C, Song J, et al. (2010) Validation of the ITS2 Region as a Novel DNA Barcode for Identifying Medicinal Plant Species. PLoSONE 5(1):e8613; Hollingsworth PM, Graham SW, Little DP (2011) Choosing and Using a Plant DNA Barcode. PLoS ONE 6(5):e19254).

[0033] The inventors conducted a complex analysis and characterization of aerosols generated from aerosol-generating substrates of the present invention incorporating chamomile particles and mixtures of chamomile and tobacco particles, and compared these aerosols with aerosols generated from existing aerosol-generating substrates formed from tobacco materials without chamomile particles. Based on this, the inventors were able to identify a group of "signature compounds" present in the aerosol that are derived from chamomile particles. Therefore, detection of these characteristic compounds within a specific range of weight percentages in the aerosol can be used to identify aerosols derived from aerosol-generating substrates containing chamomile particles. These characteristic compounds are not present in aerosols generated from tobacco materials. Furthermore, the proportions of the characteristic compounds in the aerosols and their ratios to each other clearly indicate the use of chamomile plant material, rather than chamomile oil. Similarly, the presence of these characteristic compounds in specific proportions in the aerosol-generating substrate indicates the inclusion of chamomile particles in the substrate.

[0034] In particular, the defined levels of characteristic compounds in the substrate and aerosol are specific to the chamomile particles present in the homogenized chamomile material.The level of each characteristic compound depends on the method by which the chamomile particles are processed during the production of the homogenized chamomile material.The level also depends on the composition of the homogenized chamomile material, and may be affected in particular by the levels of other components in the homogenized chamomile material.The level of characteristic compounds in the homogenized plant material may differ from the level of the same compound in the starting chamomile material.In addition, this may differ from the level of characteristic compounds in a material that contains chamomile particles but is not according to the present invention as defined herein.

[0035] To perform aerosol characterization, we used a complementary non-targeted differential screening (NTDS) using liquid chromatography coupled to a high-resolution accurate mass spectrometer (LC-HRAM-MS) in parallel with two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer (GCxGC-TOFMS).

[0036] Non-targeted screening (NTS) is an important method for characterizing the chemical composition of complex matrices, either by matching the features of unknown detected compounds to spectral databases (suspect screening [SSA]) or by elucidating unknown structures in the absence of prior knowledge by using primary fragmentation (MS / MS)-derived information that matches in silico predicted fragments from compound databases (non-targeted analysis [NTA]). NTS allows for simultaneous measurements and the ability to semi-quantitate a large number of small molecules from a sample using an unbiased approach.

[0037] As mentioned above, non-targeted differential screening (NTDS) can be performed when focusing on the comparison of two or more aerosol samples to assess significant differences in chemical composition between samples in an uncontrolled manner, or when prior knowledge of related groups is available between sample groups. Complementary differential screening using liquid chromatography coupled to a high-resolution accurate mass spectrometer (LC-HRAM-MS) in parallel with two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer (GCxGC-TOFMS) is applied to ensure comprehensive analytical coverage to identify the most relevant differences in aerosol composition between aerosols derived from an article containing 100% by weight of chamomile as particulate plant material and aerosols derived from an article containing 100% by weight of tobacco as particulate plant material.

[0038] The aerosol was generated and collected using the equipment and methods described in detail below.

[0039] LC-HRAM-MS analysis was performed using a Thermo QExactive™ high-resolution mass spectrometer in both full scan and data-dependent modes. Three different methods were applied to cover a wide range of materials with different ionization properties and compound classes. Samples were analyzed using heated electrospray ionization (HESI) in positive and negative modes, and RP chromatography with atmospheric pressure chemical ionization (APCI) in positive mode. The methods are: Arndt, D. et al, “In depth characterization of chemical differences between heat-not-burn tobacco products and cigarettes using LC-HRAM-MS-based non-targeted differential screening” (DOI:10.13140 / RG.2.2.11752.16643), Wachsmuth, C. et al, “Comprehensive chemical characterization of complex matrices through integration of multiple analytical modes and databases for LC-HRAM-MS-based non-targeted screening” (DOI:10.13140 / RG.2.2.12701.61927) and “Buchholz, C. et al, “Increasing confidence for compound identification by fragmentation database and in silico fragmentation comparison with LC-HRAM-MS-based non-targeted screening of complex matrices” (DOI:10.13140 / RG.2.2.17944.49927) (all from the 66th ASMS Conference on Mass Spectrometry and Allied Topics, San Diego, USA (2018)).The method is further described in: Arndt, D. et al., "A complex matrix characterization approach, applied to cigarette smoke, that integrates multiple analytical methods and compound identification strategies for non-targeted liquid chromatography with high-resolution mass spectrometry" (DOI: 10.1002 / rcm.8571).

[0040] GCxGC-TOFMS analysis was performed in three different ways for non-polar, polar, or highly volatile compounds in the aerosol using an Agilent GC Model 6890A or 7890A instrument equipped with an automatic liquid injector (Model 7683B) and a thermal modulator coupled to a LECO Pegasus 4D™ mass spectrometer. The methods are described in: Almstetter et al., “Non-targeted screening using GC×GC-TOFMS for in-depth chemical characterization of aerosol from a heat-not-burned tobacco product” (DOI: 10.13140 / RG.2.2.36010.31688 / 1) and Almstetter et al., “Non-targeted differential screening of complex matrices using GC×GC-TOFMS for comprehensive characterization of the chemical composition and determination of significant differences” (DOI: 10.13140 / RG.2.2.32692.55680) (66th and 64th ASMS Conferences on Mass Spectrometry and Allied Topics, San Diego, USA, respectively).

[0041] Results from the analytical method provided information about the key compounds responsible for the differences in the aerosols generated by these articles. The focus of the untargeted differential screening, using both analytical platforms LC-HRAM-MS and GCxGC-TOFMS, was on compounds that were present in greater amounts in the aerosols of a sample of an aerosol-generating substrate according to the invention containing 100 percent chamomile particles versus a comparison sample of an aerosol-generating substrate containing 100 percent tobacco particles. The NTDS method is described in the literature listed above.

[0042] Based on this information, the inventors were able to identify certain compounds within the aerosol that may be considered "signature compounds" derived from chamomile particles in the substrate. Signature compounds unique to chamomile include, but are not limited to, bisabolol oxide A ((3S,6S)-2,2,6-trimethyl-6-[(1S)-4-methylcyclohex-3-en-1-yl]oxan-3-ol, also known as α-bisabolol oxide A or bisabolol oxide I, chemical formula: C 15 H 26 O2, Chemical Abstracts Service Registry No. 58437-68-6), Tonghaos isomer ((2E)-2-hexa-2,4-dinylidene-1,6-dioxapyrro[4.4]non-3-ene) or (2Z)-2-hexa-2,4-dinylidene-1,6-dioxapyrro[4.4]non-3-ene, chemical formula: C 13 H 12 O2, Chemical Abstracts Service Registry No. 16863-61-9), and α-bisabolol (6-methyl-2-(4-methyl-3-cyclohexen-1-yl)-5-hepten-2-ol, chemical formula: C 15 H 26 O, Chemical Abstracts Service Registration No. 515-69-5).

[0043] For purposes of the present invention, targeted screening may be performed on a sample of an aerosol-generating substrate to identify the presence and amount of each of the characteristic compounds in the substrate. Such targeted screening methods are described below. As described, the characteristic compounds may be detected and measured both in the aerosol-generating substrate and in the aerosol derived from the aerosol-generating substrate.

[0044] As defined above, the aerosol-generating article of the present invention comprises an aerosol-generating substrate formed from homogenized plant material containing chamomile particles. As a result of the inclusion of chamomile particles, the aerosol-generating substrate contains a specific proportion of chamomile "characteristic compounds," as described above. In particular, the aerosol-generating substrate preferably contains, on a dry weight basis, at least 20 micrograms of bisabolol oxide A per gram of substrate, at least 100 micrograms of Tonghaos isomer per gram of substrate, and at least 15 micrograms of α-bisabolol per gram of substrate.

[0045] For purposes of the present invention, the amount of Tonghaos isomer should be considered as the total amount of Tonghaos stereoisomers: (Z)-Tonghaos and (E)-Tonghaos, or Tonghaos Isomer I and Tonghaos Isomer II, respectively.

[0046] By defining the aerosol-generating substrate for a desired level of the characteristic compound, it is possible to ensure consistency between products despite potential differences in the level of the characteristic compound in the raw materials, which advantageously allows for more effective control of product quality.

[0047] The aerosol-generating substrate preferably contains, on a dry weight basis, at least about 100 micrograms of bisabolol oxide A per gram of substrate, and more preferably at least about 250 micrograms of bisabolol oxide A per gram of substrate. Alternatively, or additionally, the aerosol-generating substrate preferably contains, on a dry weight basis, no more than about 1000 micrograms of bisabolol oxide A per gram of substrate, more preferably no more than about 750 micrograms of bisabolol oxide A per gram of substrate, and even more preferably no more than about 500 micrograms of bisabolol oxide A per gram of substrate.

[0048] For example, the aerosol-generating substrate may contain, on a dry weight basis, from about 20 micrograms to about 1000 micrograms of bisabolol oxide A per gram of substrate, or from about 100 micrograms to about 750 micrograms of bisabolol oxide A per gram of substrate, or from about 250 micrograms to about 500 micrograms of bisabolol oxide A per gram of substrate.

[0049] In certain particularly preferred embodiments, the aerosol-generating substrate may preferably contain from about 100 micrograms to about 250 micrograms of bisabolol oxide A per gram of aerosol-generating substrate, and more preferably from about 100 micrograms to about 200 micrograms of bisabolol oxide A per gram of aerosol-generating substrate. For example, the level of bisabolol oxide A may be within these ranges for preferred embodiments of the invention in which the aerosol-generating substrate contains 15 percent to 20 percent by weight of chamomile particles on a dry weight basis.

[0050] Preferably, the aerosol-generating substrate contains, on a dry weight basis, at least about 500 micrograms of Tonghaos isomer per gram of substrate, and more preferably at least about 1000 micrograms of Tonghaos isomer per gram of substrate. Alternatively, or additionally, the aerosol-generating substrate preferably contains, on a dry weight basis, no more than about 4500 micrograms of Tonghaos isomer per gram of substrate, more preferably no more than about 3000 micrograms of Tonghaos isomer per gram of substrate, and even more preferably no more than about 2000 micrograms of Tonghaos isomer per gram of substrate.

[0051] For example, the aerosol-generating substrate may contain, on a dry weight basis, from about 100 micrograms to about 4500 micrograms of Tonghaosu isomer per gram of substrate, or from about 500 micrograms to about 3000 micrograms of Tonghaosu isomer per gram of substrate, or from about 1000 micrograms to about 2000 micrograms of Tonghaosu isomer per gram of substrate.

[0052] In certain particularly preferred embodiments, the aerosol-generating substrate may preferably contain from about 800 micrograms to about 1500 micrograms of Tonghaos isomer per gram of aerosol-generating substrate, and more preferably from about 800 micrograms to about 1000 micrograms of Tonghaos isomer per gram of aerosol-generating substrate. For example, the level of Tonghaos isomer may be within these ranges for preferred embodiments of the invention in which the aerosol-generating substrate contains 15 percent to 20 percent by weight of chamomile particles on a dry weight basis.

[0053] The aerosol-generating substrate preferably contains, on a dry weight basis, at least about 100 micrograms of α-bisabolol per gram of substrate, and more preferably at least about 250 micrograms of α-bisabolol per gram of substrate. Alternatively, or additionally, the aerosol-generating substrate preferably contains, on a dry weight basis, no more than about 1000 micrograms of α-bisabolol per gram of substrate, more preferably no more than about 750 micrograms of α-bisabolol per gram of substrate, and even more preferably no more than about 500 micrograms of α-bisabolol per gram of substrate.

[0054] For example, the aerosol-generating substrate may contain, on a dry weight basis, from about 15 micrograms to about 1000 micrograms of α-bisabolol per gram of substrate, or from about 100 micrograms to about 750 micrograms of α-bisabolol per gram of substrate, or from about 250 micrograms to about 500 micrograms of α-bisabolol per gram of substrate.

[0055] In certain particularly preferred embodiments, the aerosol-generating substrate may preferably contain from about 100 micrograms to about 250 micrograms, and more preferably from about 100 micrograms to about 200 micrograms, of α-bisabolol per gram of aerosol-generating substrate. For example, the level of α-bisabolol may be within these ranges for preferred embodiments of the invention in which the aerosol-generating substrate contains 15 to 20 percent by weight of chamomile particles on a dry weight basis.

[0056] Preferably, the ratio of characteristic compounds in the aerosol-generating substrate is such that the amount of Tonghaos isomer per gram of substrate is at least four times the amount of bisabolol oxide A per gram of substrate, more preferably at least five times the amount of bisabolol oxide A per gram of substrate, and even more preferably at least six times the amount of bisabolol oxide A per gram of substrate.

[0057] Preferably, the ratio of the characteristic compounds in the aerosol-generating substrate is such that the amount of Tonghaos isomer per gram of substrate is at least 5 times the amount of α-bisabolol per gram of substrate, more preferably at least 6 times the amount of α-bisabolol per gram of substrate, and even more preferably at least 7 times the amount of α-bisabolol per gram of substrate.

[0058] These ratios of Tonghuaos isomers to bisabolol oxide A and α-bisabolol are characteristic of the inclusion of chamomile particles in the aerosol-generating substrate.

[0059] As defined above, the present invention also provides an aerosol-generating article comprising an aerosol-generating substrate formed from homogenized plant material containing chamomile particles, wherein upon heating of the aerosol-generating substrate, an aerosol containing chamomile "characteristic compounds" is generated.

[0060] For purposes of the present invention, the aerosol-generating substrate is heated in accordance with "Test Method A." In Test Method A, an aerosol-generating article incorporating the aerosol-generating substrate is heated in a Tobacco Heating System 2.2 holder (THS2.2 holder) under Health Canada's mechanical smoking regimen. For purposes of conducting Test Method A, the aerosol-generating substrate is provided in an aerosol-generating article that is compatible with a THS2.2 holder.

[0061] The Tobacco Heating System 2.2 Holder (THS2.2 Holder) corresponds to the commercially available iQOS device (Philip Morris Products SA, Switzerland) described in Smith et al., 2016, Regul. Toxicol. Pharmacol. 81(S2)S82-S92. Aerosol-generating articles for use with the IQOS device are also commercially available.

[0062] The Health Canada smoking regimen is a clearly defined and accepted smoking protocol in Health Canada's Tobacco Product Information Regulations 2000, SOR / 2000-273, Schedule 2 (published by the Canadian Ministry of Justice). The test method is described in ISO / TR 19478-1:2014. In the Health Canada smoking test, aerosol is collected from a sample aerosol-generating substrate over 12 puffs with a puff volume of 55 millimeters, a puff duration of 2 seconds, and a 30-second interval between puffs, with all ventilation, if present, shut off.

[0063] Thus, in the context of the present invention, the phrase "involving heating of an aerosol-generating substrate in accordance with Test Method A" means heating of the aerosol-generating substrate in a THS2.2 holder under the Health Canada Tobacco Product Information Regulations 2000 SOR / 2000-273, Schedule 2 (published by the Canadian Department of Justice), Health Canada's mechanical smoking regimen, which test method is described in ISO / TR 19478-1:2014.

[0064] For analytical purposes, the aerosol generated from heating the aerosol-generating substrate is trapped using appropriate equipment, depending on the analytical method being used. In a preferred method for generating samples for analysis by LC-HRAM-MS, the particle phase is trapped using a conditioned 44 mm Cambridge glass fiber filter pad (compliant with ISO 3308) and a filter holder (compliant with ISO 4387 and ISO 3308). The remaining gas phase is collected downstream from the filter pad using two consecutive microimpingers (20 mL), each containing methanol and an internal standard (ISTD) solution (10 mL), maintained at -60 °C using a mixture of dry ice and isopropanol. The trapped particle and gas phases are then recombined, and the sample is extracted from the microimpingers with methanol by shaking, stirring, and centrifuging (4500 g, 5 min, 10 °C). The resulting extract is diluted with methanol and mixed in an Eppendorf ThermoMixer (5 °C, 2000 rpm). Test samples from the extracts are analyzed by LC-HRAM-MS in a combination of full scan and data-dependent fragmentation modes to identify characteristic compounds. For the purposes of this invention, LC-HRAM-MS analysis is suitable for the identification and quantification of bisabolol oxide A and Tonghaosu isomers.

[0065] Samples for analysis by GCxGC-TOFMS can be generated in a similar manner, but for GCxGC-TOFMS analysis, different solvents are appropriate for extraction and analysis of polar, non-polar, and volatile compounds separated from the bulk aerosol.

[0066] For nonpolar and polar compounds, the whole aerosol is collected using a calibrated 44 mm Cambridge glass fiber filter pad (compliant with ISO 3308) and filter holder (compliant with ISO 4387 and ISO 3308), followed by two microimpingers connected in series and sealed. Each microimpinger (20 mL) contains 10 mL of dichloromethane / methanol (80:20 v / v) containing internal standard (ISTD) and retention index marker (RIM) compounds. The microimpingers are maintained at -80°C using a mixture of dry ice and isopropanol. For analysis of nonpolar compounds, the whole aerosol particle phase is extracted from the glass fiber filter pad using the contents of the microimpinger. Water is added to an aliquot (10 mL) of the resulting extract, and the sample is shaken and centrifuged as described above. The dichloromethane layer is separated, dried over sodium sulfate, and analyzed by GCxGC-TOFMS in full scan mode. For the analysis of polar compounds, use the remaining aqueous layer from the non-polar sample preparation described above. ISTD and RIM compounds are added to the aqueous layer, which is then directly analyzed by GCxGC-TOFMS in full scan mode.

[0067] For volatile compounds, the entire aerosol is collected using two serially connected and sealed microimpingers (20 mL), each filled with 10 mL of N,N-dimethylformamide containing the ISTD and RIM compounds. The microimpingers are maintained at -50 to -60 °C using a mixture of dry ice and isopropanol. After collection, the contents of the two microimpingers are combined and analyzed by GCxGC-TOFMS in full scan mode.

[0068] For the purposes of the present invention, GCxGC-TOFMS analysis is suitable for the differentiation and quantification of bisabolol oxide A, Tonghaosu isomers, and α-bisabolol.

[0069] The aerosol generated upon heating of the aerosol-generating substrate of the present invention according to Test Method A is preferably characterized by the amounts and ratios of the characteristic compounds bisabolol oxide A, Tonghuas isomers and α-bisabolol, as defined above.

[0070] In an aerosol-generating article comprising the aerosol-generating substrate described above, heating the aerosol-generating substrate in accordance with Test Method A preferably generates an aerosol containing at least 5 micrograms of bisabolol oxide A per gram of substrate, on a dry weight basis, at least 5 micrograms of Tonghaos isomer per gram of substrate, on a dry weight basis, and at least 3 micrograms of α-bisabolol per gram of substrate.

[0071] The ranges define the amount of each characteristic compound in the generated aerosol per gram of aerosol-generating substrate (also referred to herein as "substrate"), which is equal to the total amount of characteristic compounds measured in the aerosol collected during Test Method A divided by the dry weight of the aerosol-generating substrate before heating.

[0072] Preferably, heating the aerosol-generating substrate according to Test Method A generates an aerosol containing, on a dry weight basis, at least about 20 micrograms of bisabolol oxide A per gram of substrate. More preferably, the aerosol generated from an aerosol-generating substrate according to the present invention contains, on a dry weight basis, at least about 50 micrograms of bisabolol oxide A per gram of substrate.

[0073] Alternatively or additionally, the aerosol generated by the aerosol-generating substrate preferably contains, on a dry weight basis, at most about 250 micrograms of bisabolol oxide A per gram of substrate. More preferably, the aerosol generated by the aerosol-generating substrate contains, on a dry weight basis, at most about 200 micrograms of bisabolol oxide A per gram of substrate. Even more preferably, the aerosol generated by the aerosol-generating substrate contains, on a dry weight basis, at most about 100 micrograms of bisabolol oxide A per gram of substrate.

[0074] Preferably, heating the aerosol-generating substrate according to Test Method A generates an aerosol containing at least about 20 micrograms of Tonghaos isomer per gram of substrate, on a dry weight basis. More preferably, the aerosol generated from an aerosol-generating substrate according to the present invention contains at least about 50 micrograms of Tonghaos isomer per gram of substrate, on a dry weight basis.

[0075] Alternatively or additionally, the aerosol generated by the aerosol-generating substrate preferably contains, on a dry weight basis, at most about 250 micrograms of Tonghaos isomer per gram of substrate. More preferably, the aerosol generated by the aerosol-generating substrate contains, on a dry weight basis, at most about 200 micrograms of Tonghaos isomer per gram of substrate. Even more preferably, the aerosol generated by the aerosol-generating substrate contains, on a dry weight basis, at most about 100 micrograms of Tonghaos isomer per gram of substrate.

[0076] Preferably, heating the aerosol-generating substrate according to Test Method A generates an aerosol containing at least about 20 micrograms of α-bisabolol per gram of substrate, on a dry weight basis. More preferably, the aerosol generated from an aerosol-generating substrate according to the present invention contains at least about 50 micrograms of α-bisabolol per gram of substrate, on a dry weight basis.

[0077] Alternatively or additionally, the aerosol generated by the aerosol-generating substrate preferably contains, on a dry weight basis, at most about 200 micrograms of α-bisabolol per gram of substrate. More preferably, the aerosol generated by the aerosol-generating substrate contains, on a dry weight basis, at most about 150 micrograms of α-bisabolol per gram of substrate. Even more preferably, the aerosol generated by the aerosol-generating substrate contains, on a dry weight basis, at most about 100 micrograms of α-bisabolol per gram of substrate.

[0078] The aerosol generated from the aerosol-generating substrate of the present invention during Test Method A preferably contains at least about 0.1 micrograms of nicotine per gram of substrate, more preferably at least about 1 microgram of nicotine per gram of substrate, and even more preferably at least about 2 micrograms of nicotine per gram of substrate. The aerosol preferably contains at most about 10 micrograms of nicotine per gram of substrate, more preferably at most about 7.5 micrograms of nicotine per gram of substrate, and even more preferably at most about 4 micrograms of nicotine per gram of substrate. For example, the aerosol may contain from about 0.1 micrograms to about 10 micrograms of nicotine per gram of substrate, or from about 1 microgram to about 7.5 micrograms of nicotine per gram of substrate, or from about 2 micrograms to about 4 micrograms of nicotine per gram of substrate. In some embodiments of the present invention, the aerosol may contain zero micrograms of nicotine.

[0079] Various methods known in the art can be applied to measure the amount of nicotine in the aerosol.

[0080] Alternatively, or in addition, the aerosol generated from an aerosol-generating substrate according to the present invention during Test Method A may optionally further comprise at least about 20 milligrams of cannabinoid compound per gram of substrate, more preferably at least about 50 milligrams of cannabinoid compound per gram of substrate, and more preferably at least about 100 milligrams of cannabinoid compound per gram of substrate. Preferably, the aerosol comprises up to about 250 milligrams of cannabinoid compound per gram of substrate, more preferably up to about 200 milligrams of cannabinoid compound per gram of substrate, and even more preferably up to about 150 milligrams of cannabinoid compound per gram of substrate. For example, the aerosol may comprise from about 20 milligrams to about 250 milligrams of cannabinoid compound per gram of substrate, or from about 50 milligrams to about 200 milligrams of cannabinoid compound per gram of substrate, or from about 100 milligrams to about 150 milligrams of cannabinoid compound per gram of substrate. In some embodiments of the present invention, the aerosol may contain zero micrograms of cannabinoid compounds.

[0081] Preferably the cannabinoid compound is selected from CBD and THC, more preferably the cannabinoid compound is CBD.

[0082] Various methods known in the art can be applied to measure the amount of cannabinoid compounds in the aerosol.

[0083] Carbon monoxide may also be present in the aerosol generated from an aerosol-generating substrate according to the present invention during Test Method A, and can be measured and used to further characterize the aerosol. Oxides of nitrogen, such as nitric oxide and nitrogen dioxide, may also be present in the aerosol, and can be measured and used to further characterize the aerosol.

[0084] According to the present invention, the aerosol generated from the aerosol-generating substrate during Test Method A preferably has an amount of Tonghaos isomer per gram of substrate that is at least 0.75 times the amount of bisabolol oxide A per gram of substrate. Thus, the ratio of Tonghaos isomer to bisabolol oxide A is at least 0.75:1. More preferably, the amount of Tonghaos isomer in the aerosol produced from the aerosol-generating substrate during Test Method A is at least equal to the amount of bisabolol oxide A per gram of substrate, such that the ratio of Tonghaos isomer to bisabolol oxide A is at least 1:1.

[0085] According to the present invention, the aerosol generated from the aerosol-generating substrate during Test Method A preferably has an amount of Tonghaos isomer per gram of substrate that is at least 0.75 times the amount of α-bisabolol per gram of substrate. Thus, the ratio of Tonghaos isomer to α-bisabolol is at least 1:1. More preferably, the amount of Tonghaos isomer in the aerosol produced from the aerosol-generating substrate during Test Method A is at least 1.5 times the amount of α-bisabolol per gram of substrate, such that the ratio of Tonghaos isomer to α-bisabolol is at least 1.5:1.

[0086] A defined ratio of Tonghaos isomers to bisabolol oxide A and α-bisabolol characterizes aerosols derived from chamomile particles. In contrast, the ratio of Tonghaos isomers to bisabolol oxide A and α-bisabolol in aerosols generated from chamomile oil will be significantly different.

[0087] The aerosol generated from an aerosol-generating substrate of the present invention during Test Method A may further comprise at least about 5 milligrams of aerosol former per gram of aerosol-generating substrate, or at least about 10 milligrams of aerosol per gram of substrate, or at least about 15 milligrams of aerosol former per gram of substrate. Alternatively or additionally, the aerosol may comprise up to about 30 milligrams of aerosol former per gram of substrate, or up to about 25 milligrams of aerosol former per gram of substrate, or up to about 20 milligrams of aerosol former per gram of substrate. For example, the aerosol may comprise from about 5 milligrams to about 30 milligrams of aerosol former per gram of substrate, or from about 10 milligrams to about 25 milligrams of aerosol former per gram of substrate, or from about 15 milligrams to about 20 milligrams of aerosol former per gram of substrate. In alternative embodiments, the aerosol may comprise less than 5 milligrams of aerosol former per gram of substrate. This may be appropriate, for example, where the aerosol former is provided separately within the aerosol-generating article or device.

[0088] Suitable aerosol formers for use in the present invention are described below.

[0089] Various methods known in the art can be applied to measure the amount of aerosol formers in an aerosol.

[0090] As mentioned above, the presence and defined amounts and ratios of characteristic compounds in the aerosol indicate the inclusion of chamomile particles in the homogenized plant material forming the aerosol-generating substrate.

[0091] Aerosol-generating substrates according to the present invention preferably comprise a homogenized chamomile material containing at least about 2.5 weight percent chamomile particles on a dry weight basis. Preferably, the homogenized chamomile material contains at least about 3 weight percent chamomile particles, more preferably at least about 4 weight percent chamomile particles, more preferably at least about 5 weight percent chamomile particles, more preferably at least about 6 weight percent chamomile particles, more preferably at least about 7 weight percent chamomile particles, more preferably at least about 8 weight percent chamomile particles, more preferably at least about 9 weight percent chamomile particles, and more preferably at least about 10 weight percent chamomile particles on a dry weight basis.

[0092] In certain embodiments of the present invention, the plant particles forming the homogenized chamomile material may contain at least 98 weight percent chamomile particles, or at least 95 weight percent chamomile particles, or at least 90 weight percent chamomile particles, based on the dry weight of the plant particles. Thus, in such embodiments, the aerosol-generating substrate contains chamomile particles and is substantially free of other plant particles. For example, the plant particles forming the homogenized chamomile material may contain about 100 weight percent chamomile particles.

[0093] In an alternative embodiment of the present invention, the homogenized chamomile material may include chamomile particles in combination with at least one of tobacco particles or cannabis particles, as described below.

[0094] In the following description of the invention, the term "particulate plant material" is used to collectively refer to the particles of plant material used to form the homogenized plant material. The particulate plant material may consist essentially of chamomile particles, or may be a mixture of chamomile particles with tobacco particles, cannabis particles, or both tobacco particles and cannabis particles.

[0095] The homogenized chamomile material may contain up to about 100 weight percent chamomile particles on a dry weight basis, preferably up to about 90 weight percent chamomile particles, more preferably up to about 80 weight percent chamomile particles, even more preferably up to about 70 weight percent chamomile particles, even more preferably up to about 60 weight percent chamomile particles, and even more preferably up to about 50 weight percent chamomile particles on a dry weight basis.

[0096] For example, the homogenized chamomile material may contain, on a dry weight basis, from about 2.5 weight percent to about 100 weight percent chamomile particles, or from about 5 weight percent to about 90 weight percent chamomile particles, or from about 10 weight percent to about 80 weight percent chamomile particles, or from about 15 weight percent to about 70 weight percent chamomile particles, or from about 20 weight percent to about 60 weight percent chamomile particles, or from about 30 weight percent to about 50 weight percent chamomile particles.

[0097] In certain particularly preferred embodiments of the present invention, the homogenized chamomile material comprises, on a dry weight basis, from about 15 weight percent to about 20 weight percent chamomile particles.

[0098] As discussed above, the inventors have identified a number of "signature compounds," which are compounds that are characteristic of the chamomile plant and therefore indicative of the inclusion of chamomile plant particles within the aerosol-generating substrate.

[0099] It is expected that the amount of characteristic compounds present in pure chamomile particles will be different from the amount present in aerosol-generating substrate.The process of making substrate, including hydration in slurry or suspension and drying at high temperature, and the presence of other components such as aerosol formers, will modify the amount of each characteristic compound differently.The integrity of chamomile particles and the stability of compounds under temperature and operation during manufacturing will also affect the final amount of compounds present in substrate.Therefore, it is expected that after chamomile particles are incorporated into various physical forms, such as sheet, strand and granule substrates, the ratio of characteristic compounds to each other may be different.

[0100] The presence of chamomile in the aerosol-generating substrate and the proportion of chamomile provided in the aerosol-generating substrate can be determined by measuring the amount of the characteristic compound in the substrate and comparing it to the corresponding amount of the characteristic compound in pure chamomile material. The presence and amount of the characteristic compound can be determined using any suitable technique that would be known to one skilled in the art.

[0101] In a suitable technique, a 250-milligram sample of aerosol-generating substrate is mixed with 5 milliliters of methanol and extracted by shaking, stirring for 5 minutes, and centrifugation (4500 g, 10°C, 5 minutes). An aliquot of the extract (300 microliters) is transferred to a silanized chromatography vial and diluted with methanol (600 microliters) and internal standard (ISTD) solution (100 microliters). The vial is closed and mixed for 5 minutes using an Eppendorf ThermoMixer (5°C, 2000 rpm). Samples from the resulting extract are analyzed by LC-HRAM-MS in a combination of full scan and data-dependent fragmentation modes for identification of characteristic compounds.

[0102] In some embodiments, the homogenized chamomile material further comprises up to about 75 weight percent tobacco particles on a dry weight basis.

[0103] For example, the homogenized chamomile material preferably contains, on a dry weight basis, from about 10 weight percent to about 75 weight percent tobacco particles, more preferably from about 15 weight percent to about 70 weight percent tobacco particles, more preferably from about 20 weight percent to about 65 weight percent tobacco particles, more preferably from about 25 weight percent to about 60 weight percent tobacco particles, and even more preferably from about 30 weight percent to about 70 weight percent tobacco particles.

[0104] In some preferred embodiments, the homogenized chamomile material comprises, on a dry weight basis, from about 5 percent to about 20 percent by weight chamomile particles and from about 55 percent to about 70 percent by weight tobacco particles.

[0105] The weight ratio of chamomile particles to tobacco particles in the particulate plant material forming the homogenized chamomile material can vary depending on the desired flavor characteristics and composition of the aerosol. Preferably, the homogenized chamomile material contains a weight ratio of chamomile particles to tobacco particles of 1:4 or less, meaning that the chamomile particles account for 20 percent or less of the total particulate plant material. More preferably, the homogenized chamomile material contains a weight ratio of chamomile particles to tobacco particles of 1:5 or less, more preferably 1:6 or less.

[0106] For example, in a first preferred embodiment, the weight ratio of chamomile particles to tobacco particles is 1:4. A ratio of 1:4 corresponds to a particulate plant material consisting of about 20 weight percent chamomile particles and about 80 weight percent tobacco particles. For a homogenized chamomile material formed with about 75 weight percent particulate plant material, this corresponds to about 15 weight percent chamomile particles and about 60 weight percent tobacco particles in the homogenized chamomile material on a dry weight basis.

[0107] In another embodiment, the homogenized chamomile material comprises a weight ratio of chamomile particles to tobacco particles of 1:9. In yet another embodiment, the homogenized chamomile material comprises a weight ratio of chamomile particles to tobacco particles of 1:30.

[0108] For purposes of the present invention, the term "tobacco particles" describes particles of any plant material of the Nicotiana species. The term "tobacco particles" encompasses ground or powdered tobacco lamina, ground or powdered tobacco stems, tobacco dust, tobacco fines, and other particulate tobacco by-products formed during tobacco processing, handling, and shipping. In preferred embodiments, the tobacco particles are derived substantially entirely from tobacco lamina. In contrast, isolated nicotine and nicotine salts, although tobacco-derived compounds, are not considered tobacco particles for purposes of the present invention and are not included in the proportion of particulate plant material.

[0109] The tobacco particles may be prepared from one or more tobacco plant varieties. Any type of tobacco may be used in the blend. Examples of types of tobacco materials that may be used include, but are not limited to, sun-cured tobacco, flue-cured tobacco, burley tobacco, Maryland tobacco, Orient tobacco, Virginia tobacco, and other specialty tobaccos.

[0110] Flame-curing is a tobacco curing method used specifically with Virginia tobacco. During the flue-curing process, heated air is circulated through tightly packed tobacco. During the first stage, the tobacco leaves yellow and wither. During the second stage, the leaf lamina dries completely. During the third stage, the leaf stem dries completely.

[0111] Burley tobacco plays an important role in many tobacco blends. It has a unique flavor and aroma and the ability to absorb large amounts of casing.

[0112] Orient is a type of tobacco with small leaves and high aromatic qualities. However, Orient tobacco has a milder flavor than, for example, Burley. Therefore, Orient tobacco is generally used in relatively small proportions in tobacco blends.

[0113] Kasturi, Madura, and Jatim are subtypes of sun-cured tobacco that can be used. Preferably, Kasturi and flue-cured tobaccos are blended to produce tobacco particles. Thus, the tobacco particles in the particulate plant material can comprise a blend of Kasturi and flue-cured tobaccos.

[0114] The tobacco particles may have a nicotine content of at least about 2.5 weight percent on a dry weight basis. More preferably, the tobacco particles may have a nicotine content of at least about 3 weight percent on a dry weight basis, even more preferably at least about 3.2 weight percent, even more preferably at least about 3.5 weight percent, and most preferably at least about 4 weight percent. When the aerosol-generating substrate comprises tobacco particles in combination with chamomile particles, the high-nicotine tobacco preferably maintains a similar level of nicotine to a typical aerosol-generating substrate without chamomile particles, since the total amount of nicotine would otherwise be reduced due to the substitution of tobacco particles for chamomile particles.

[0115] As a result of the inclusion of tobacco particles, the aerosol-generating substrates and the aerosols generated therefrom of these embodiments contain a particular proportion of "signature compounds" of tobacco. Characteristic compounds generated from tobacco include, but are not limited to, anatabine, cotinine, and damascenone.

[0116] Nicotine may optionally be incorporated into the aerosol-generating substrate, which for purposes of the present invention is considered a non-tobacco material. The nicotine may comprise one or more nicotine salts selected from the list consisting of nicotine lactate, nicotine citrate, nicotine pyruvate, nicotine bitartrate, nicotine benzoate, nicotine pectinate, nicotine alginate, and nicotine salicylate. The nicotine may be incorporated in addition to low-nicotine tobacco, or the nicotine may be incorporated into an aerosol-generating substrate having reduced or no tobacco content.

[0117] In certain embodiments of the invention, the aerosol-generating substrate comprises homogenized chamomile material formed from particulate plant material consisting solely of chamomile particles, having nicotine, such as a nicotine salt, incorporated into the aerosol-generating substrate.

[0118] Preferably, the aerosol-generating substrate comprises at least about 0.1 mg of nicotine per gram of substrate on a dry weight basis, more preferably at least about 0.5 mg of nicotine per gram of substrate, more preferably at least about 1 mg of nicotine per gram of substrate, more preferably at least about 1.5 mg of nicotine per gram of substrate, more preferably at least about 2 mg of nicotine per gram of substrate, more preferably at least about 3 mg of nicotine per gram of substrate, more preferably at least about 4 mg of nicotine per gram of substrate, more preferably at least about 5 mg of nicotine per gram of substrate on a dry weight basis.

[0119] Preferably, the aerosol-generating substrate contains, on a dry weight basis, a maximum of about 50 mg of nicotine per gram of substrate, more preferably, a maximum of about 45 mg of nicotine per gram of substrate, more preferably, a maximum of about 40 mg of nicotine per gram of substrate, more preferably, a maximum of about 35 mg of nicotine per gram of substrate, more preferably, a maximum of about 30 mg of nicotine per gram of substrate, more preferably, a maximum of about 25 mg of nicotine per gram of substrate, more preferably, a maximum of about 20 mg of nicotine per gram of substrate.

[0120] For example, the aerosol-generating substrate may contain, on a dry weight basis, from about 0.1 mg to about 50 mg of nicotine per gram of substrate, or from about 0.5 mg to about 45 mg of nicotine per gram of substrate, or from about 1 mg to about 40 mg of nicotine per gram of substrate, or from about 2 mg to about 35 mg of nicotine per gram of substrate, or from about 5 mg to about 30 mg of nicotine per gram of substrate, or from about 10 mg to about 25 mg of nicotine per gram of substrate, or from about 15 mg to about 20 mg of nicotine per gram of substrate. In certain preferred embodiments of the invention, the aerosol-generating substrate contains, on a dry weight basis, from about 1 mg to about 20 mg of nicotine per gram of substrate.

[0121] The defined range of nicotine content for the aerosol-generating substrate includes all forms of nicotine that may be present in the aerosol-generating substrate, including nicotine inherently present in the tobacco material, as well as nicotine optionally added separately to the aerosol-generating substrate, for example in the form of a nicotine salt.

[0122] As an alternative to, or in addition to, including tobacco particles in the homogenized chamomile material of an aerosol-generating substrate according to the present invention, the homogenized chamomile material may include up to 75 weight percent cannabis particles on a dry weight basis. The term "cannabis particles" refers to particles of cannabis plants, such as Cannabis sativa, Cannabis indica, and Cannabis ruderalis.

[0123] For example, the particulate plant material may comprise, on a dry weight basis, from about 40 weight percent to about 75 weight percent cannabis particles, more preferably from about 45 weight percent to about 60 weight percent tobacco particles, and more preferably from about 50 weight percent to about 65 weight percent tobacco particles.

[0124] One or more cannabinoid compounds may optionally be incorporated into the aerosol-generating substrate, but this is considered a non-cannabis material for purposes of the present invention. As used herein with respect to the present invention, the term "cannabinoid compound" describes any one of a class of naturally occurring compounds found in parts of the cannabis plant, i.e., Cannabis sativa, Cannabis indica, and Cannabis ruderalis. Cannabinoid compounds are particularly concentrated in the female flower heads and are commonly sold as cannabis oil. Naturally occurring cannabinoid compounds in the cannabis plant include tetrahydrocannabinol (THC) and cannabidiol (CBD). In the context of the present invention, the term "cannabinoid compound" is used to describe both naturally occurring and synthetically produced cannabinoid compounds.

[0125] For example, the aerosol-generating substrate may comprise a cannabinoid compound selected from the group consisting of tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), cannabidiol (CBD), cannabidiolic acid (CBDA), cannabinol (CBN), cannabigerol (CBG), cannabigerol monomethyl ether (CBGM), cannabivarin (CBV), cannabidivarin (CBDV), tetrahydrocannabivarin (THCV), cannabichromene (CBC), cannabicyclol (CBL), cannabichromevarin (CBCV), cannabigerovarin (CBGV), cannabielsoin (CBE), cannabicitran (CBT), and combinations thereof.

[0126] The homogenized chamomile material may further comprise a proportion of other plant-flavored particles in addition to chamomile particles or a combination of chamomile particles and at least one of tobacco particles and cannabis particles ("particulate plant material").

[0127] For purposes of the present invention, the term "other botanical flavor particles" refers to particles of non-chamomile, non-tobacco, and non-cannabis plant material capable of releasing one or more flavoring agents upon heating. This term is intended to exclude particles of inert plant material, such as cellulose, that do not contribute to the sensory output of the aerosol-generating substrate. The particles may be derived from crushed or powdered leaf laminae, fruits, petioles, stems, roots, seeds, buds, or peels from other plants. Suitable botanical flavor particles for inclusion in aerosol-generating substrates according to the present invention are known to those skilled in the art and include, but are not limited to, clove particles and tea particles.

[0128] The composition of the homogenized chamomile material can be advantageously adjusted by blending desired amounts and types of different plant particles. This allows aerosol-generating substrates to be formed from a single homogenized chamomile material, as desired, without the need to combine or mix different blends, as is the case, for example, in the manufacture of conventional cut fillers. Thus, the manufacture of aerosol-generating substrates can potentially be simplified.

[0129] The particulate plant material used in the aerosol-generating substrate of the present invention can be adapted to provide a desired particle size distribution. The particle size distribution herein is described as a D value, whereby the D value refers to the percentage of particles having a diameter equal to or less than a given D value. For example, in a D95 particle size distribution, 95 percent of the particles have a diameter equal to or less than a given D95 value, and 5 percent of the particles have a diameter greater than the given D95 value. Similarly, in a D5 particle size distribution, 5 percent of the particles have a diameter equal to or less than the D5 value, and 95 percent of the particles have a diameter greater than the given D5 value. Thus, in combination, the D5 and D95 ​​values ​​provide an indication of the particle size distribution of the particulate plant material.

[0130] The particulate plant material may have a D95 value of 50 microns or more to 400 microns or less. This means that the particulate plant material may have a distribution represented by any D95 value within a given range, i.e., the D95 may be 50 microns, or the D95 may be 55 microns, etc., up to a maximum of 400 microns. By providing a D95 value within this range, the inclusion of relatively large plant particles within the homogenized chamomile material is avoided. This is desirable because aerosol generation from such large plant particles is likely to be relatively inefficient. Furthermore, the inclusion of large plant particles in the homogenized chamomile material may adversely affect the consistency of the material.

[0131] The particulate plant material may preferably have a D95 value of from about 50 microns or more to about 350 microns or less, more preferably from about 75 microns or more to about 300 microns or less. Both the particulate chamomile material and the particulate tobacco material may have a D95 value of from about 50 microns or more to about 400 microns or less, preferably from about 75 microns or more to about 350 microns or less, more preferably from about 100 microns or more to about 300 microns or less.

[0132] Preferably, the particulate plant material may have a D5 value of about 10 microns or more to about 50 microns or less, and more preferably about 20 microns or more to about 40 microns or less. Providing a D5 value within this range avoids the inclusion of very small dust particles in the homogenized chamomile material, which may be desirable from a manufacturing standpoint.

[0133] In some embodiments, the particulate plant material may be intentionally ground to form particles having a desired particle size distribution. The use of intentionally ground tobacco advantageously improves the homogeneity of the particulate plant material and the consistency of the homogenized chamomile material.

[0134] The diameter of 100 percent of the particulate plant material may be about 300 microns or less, more preferably about 275 microns or less. The diameter of 100 percent of the particulate chamomile material and 100 percent of the particulate tobacco material may be about 300 microns or less, more preferably about 275 microns or less. The particle size range of the chamomile particles allows them to be combined with tobacco particles in existing cast leaf processes.

[0135] The homogenized chamomile material preferably comprises, on a dry weight basis, at least about 55 weight percent particulate plant material, more preferably at least about 60 weight percent particulate plant material, and more preferably at least about 65 weight percent particulate plant material, including chamomile particles as described above. The homogenized chamomile material preferably comprises, on a dry weight basis, no more than about 95 weight percent particulate plant material, more preferably no more than about 90 weight percent particulate plant material, and more preferably no more than about 85 weight percent particulate plant material. For example, the homogenized chamomile material may comprise, on a dry weight basis, from about 55 weight percent to about 95 weight percent particulate plant material, or from about 60 weight percent to about 90 weight percent particulate plant material, or from about 65 weight percent to about 85 weight percent particulate plant material. In one particularly preferred embodiment, the homogenized chamomile material comprises, on a dry weight basis, about 75 weight percent particulate plant material.

[0136] Thus, the particulate plant material is typically combined with one or more other ingredients to form a homogenized chamomile material.

[0137] As defined above, the homogenized chamomile material further includes an aerosol former. Upon volatilization, the aerosol former can carry other vaporized compounds, such as nicotine and flavorings in the aerosol, that are released from the aerosol-generating substrate upon heating. The aerosolization of a particular compound from the aerosol-generating substrate is not determined solely by its boiling point. The amount of a compound aerosolized can be affected by the physical form of the substrate as well as other components present in the substrate. The stability of the compound under the temperature and time frame of aerosolization also affects the amount of compound present in the aerosol.

[0138] Aerosol formers suitable for inclusion in the homogenized chamomile material are known in the art and include, but are not limited to, polyhydric alcohols (such as triethylene glycol, propylene glycol, 1,3-butanediol, and glycerol), esters of polyhydric alcohols (such as glycerol mono-, di-, or triacetate), and aliphatic esters of mono-, di-, or polycarboxylic acids (such as dimethyl dodecanedioate and tetradecanedioate). The homogenized chamomile material can contain a single aerosol former or a combination of two or more aerosol formers.

[0139] The homogenized chamomile material preferably has an aerosol former content of from about 5 weight percent to about 30 weight percent on a dry weight basis, such as from about 10 weight percent to about 25 weight percent on a dry weight basis, or from about 15 weight percent to about 20 weight percent on a dry weight basis.

[0140] For example, when the substrate is intended for use in an aerosol-generating article for an electrically-operated aerosol-generating system having a heating element, the aerosol former content may preferably be about 5 weight percent to about 30 weight percent on a dry weight basis.When the substrate is intended for use in an aerosol-generating article for an electrically-operated aerosol-generating system having a heating element, the aerosol former is preferably glycerol.

[0141] In other embodiments, the homogenized chamomile material may have an aerosol former content of about 1 percent to about 5 percent by weight on a dry weight basis. For example, if the substrate is intended for use in an aerosol-generating article in which the aerosol former is held in a reservoir separate from the substrate, the substrate may have an aerosol former content of greater than 1 percent and less than about 5 percent. In such embodiments, the aerosol former volatilizes upon heating, and the aerosol former stream contacts the aerosol-generating substrate so as to incorporate flavors from the aerosol-generating substrate into the aerosol.

[0142] The aerosol former may act as a wetting agent in the aerosol-generating substrate.

[0143] As defined above, the homogenized chamomile material further comprises a binder for modifying the mechanical properties of the particulate plant material, wherein the binder is included in the homogenized chamomile material during production as described herein. Suitable exogenous binders known to those skilled in the art are known in the art and include, but are not limited to, gums such as guar gum, xanthan gum, gum arabic, and locust bean gum; cellulosic binders such as hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, and ethyl cellulose; polysaccharides such as starch, organic acids such as alginic acid, sodium alginate, agar, and conjugate base salts of organic acids such as pectin, and combinations thereof. Preferably, the binder comprises guar gum.

[0144] The binder is preferably present in an amount of about 1 weight percent to about 10 weight percent based on the dry weight of the homogenized chamomile material, and preferably in an amount of about 2 weight percent to about 5 weight percent based on the dry weight of the homogenized chamomile material.

[0145] In addition, the homogenized chamomile material may optionally further comprise one or more lipids to promote the diffusion rate of the volatile components (e.g., aerosol formers, (E)-anethole, and nicotine), the lipids being included in the homogenized chamomile material during manufacture as described herein. Suitable lipids for inclusion in the homogenized plant material include, but are not limited to, medium-chain triglycerides, cocoa butter, palm oil, palm kernel oil, mango oil, shea butter, soybean oil, cottonseed oil, coconut oil, hydrogenated coconut oil, candelilla wax, carnauba wax, shellac, sunflower wax, sunflower oil, rice bran, and Revel A, and combinations thereof.

[0146] Alternatively, or additionally, the homogenized chamomile material may further comprise a pH adjuster.

[0147] Alternatively, or in addition, the homogenized chamomile material may further contain fibers to change the mechanical properties of the homogenized chamomile material, where the fibers are included in the homogenized chamomile material during the manufacturing process described herein. Suitable exogenous fibers for inclusion in the homogenized chamomile material are known in the art and include fibers formed from non-tobacco and non-chamomile materials, including, but not limited to, cellulose fibers, soft wood fibers, hard wood fibers, jute fibers, and combinations thereof. Exogenous fibers derived from tobacco and / or chamomile may also be added. Any fibers added to the homogenized chamomile material are not considered to form part of the "particulate plant material" defined above. Before being included in the homogenized chamomile material, the fibers may be processed by any suitable process known in the art, including, but not limited to, mechanical pulping, refining, chemical pulping, bleaching, sulfate pulping, and combinations thereof. Typically, the fibers have a length greater than their width.

[0148] Suitable fibers are typically greater than 400 micrometers and have lengths of 4 mm or less, preferably in the range of 0.7 mm to 4 mm. Preferably, the fibers are present in an amount of at least about 2 weight percent, based on the dry weight of the substrate. The amount of fiber in the homogenized chamomile material may depend on the type of material, particularly the method used to produce the homogenized chamomile material. In some embodiments, the fibers may be present in an amount of about 2 to about 15 weight percent, most preferably about 4 weight percent, based on the dry weight of the substrate. For example, this level of fiber may be present where the homogenized plant material is in the form of cast leaves. In other embodiments, the fibers may be present in an amount of at least about 30 weight percent, or at least about 40 weight percent. For example, this higher level of fiber is likely to be provided when the homogenized chamomile material is chamomile paper formed in a papermaking process.

[0149] In a preferred embodiment of the present invention, the homogenized chamomile material comprises, on a dry weight basis, chamomile particles, from about 5 to about 30 weight percent aerosol former, and from about 1 to about 10 weight percent binder. In such an embodiment, the homogenized chamomile material preferably further comprises from about 2 to about 15 weight percent fiber. A particularly preferred binder is guar gum.

[0150] The homogenized plant material of the aerosol-generating substrate according to the present invention may comprise a single type of homogenized plant material, or two or more types of homogenized plant material having different compositions or morphologies. For example, in one embodiment, the aerosol-generating substrate comprises chamomile particles and tobacco or cannabis particles contained within the same sheet of homogenized plant material. However, in other embodiments, the aerosol-generating substrate may comprise tobacco or cannabis particles and chamomile particles within different sheets.

[0151] The homogenized chamomile material is preferably in the form of a solid or gel. However, in some embodiments, the homogenized material may be in the form of a solid that is not a gel. Preferably, the homogenized material is not in the form of a film.

[0152] The homogenized plant material may be provided in any suitable form. For example, the homogenized chamomile material may be in the form of one or more sheets. As used herein with respect to the present invention, the term "sheet" describes a laminar element having a width and length that is substantially greater than its thickness.

[0153] Alternatively, or additionally, the homogenized chamomile material may be in the form of a plurality of pellets or granules.

[0154] Alternatively, or additionally, the homogenized chamomile material may be in a form that can fill a cartridge or shisha consumable or be used in a shisha device. The present invention includes a cartridge or shisha device that includes the homogenized chamomile material.

[0155] Alternatively, or in addition, the homogenized chamomile material may be in the form of a plurality of strands, strips, or pieces. As used herein, the term "strand" describes an elongated element of material having a length substantially greater than its width and thickness. The term "strand" is considered to encompass strips, pieces, and any other homogenized chamomile material having a similar form. Strands of homogenized chamomile material may be formed from a sheet of homogenized chamomile material, for example, by cutting or chopping, or by other methods, such as extrusion.

[0156] In some embodiments, the strands may be formed in situ within the aerosol-generating substrate as a result of splitting or cracking of a sheet of homogenized chamomile material during the formation of the aerosol-generating substrate, e.g., as a result of crimping. The strands of homogenized chamomile material within the aerosol-generating substrate may be separated from one another. Alternatively, each strand of homogenized chamomile material within the aerosol-generating substrate may be at least partially connected to adjacent strands along its length. For example, adjacent strands may be connected by one or more fibers. This may occur, for example, when strands are formed due to splitting of a sheet of homogenized chamomile material during the manufacture of the aerosol-generating substrate, as described above.

[0157] The aerosol-generating substrate is preferably in the form of one or more sheets of homogenized chamomile material. In various embodiments of the present invention, the one or more sheets of homogenized chamomile material may be produced by a casting process. In various embodiments of the present invention, the one or more sheets of homogenized chamomile material may be produced by a papermaking process. The one or more sheets described herein may each individually have a thickness of 100 micrometers to 600 micrometers, preferably 150 micrometers to 300 micrometers, and most preferably 200 micrometers to 250 micrometers. Individual thickness refers to the thickness of an individual sheet, while combined thickness refers to the total thickness of all sheets comprising the aerosol-generating substrate. For example, if the aerosol-generating substrate is formed from two individual sheets, the combined thickness is the thickness of the two individual sheets or the sum of the measured thicknesses of the two sheets when the two sheets are stacked within the aerosol-generating substrate.

[0158] One or more of the sheets described herein may each individually have a weight of about 100 g / m 2 ~about 300g / m 2 The sheet may have a basis weight of 1000 gram.

[0159] One or more of the sheets described herein may each individually have a density of about 0.3 g / cm3 ~Approx. 1.3g / cm 3 and may have a density of about 0.7 g / cm 3 ~Approx. 1.0g / cm 3 It is preferred that the density of the cellulose acylate is 0.05 to 0.15.

[0160] The term "tensile strength" is used throughout this specification to refer to the measurement of the force required to stretch a homogenized chamomile material to breakage. More specifically, tensile strength is the maximum pulling force per unit width that a sheet material will withstand before breaking, measured in either the machine direction or the cross direction of the sheet material. It is expressed in units of Newtons per meter of material (N / m). Tests for measuring the tensile strength of sheet materials are well known. A suitable test is described in the 2014 edition of International Standard ISO 1924-2, entitled "Paper and paperboard - Test methods for tensile properties - Part 2: Constant rate of extension method."

[0161] The materials and equipment required to perform the test in accordance with ISO 1924-2 are a general-purpose tension / compression testing machine (Instron 5566 or equivalent), a 100 Newton tensile load cell (Instron or equivalent), two pneumatically operated grips, a 180 ± 0.25 mm long steel gauge block (approximately 10 mm wide and 3 mm thick), a double-blade strip cutter (size 15 ± 0.05 x approximately 250 mm, Adamel Lhomargy or equivalent), a scalpel, computer-operated acquisition software (Merlin or equivalent), and compressed air.

[0162] Samples are prepared by first conditioning a sheet of homogenized chamomile material at 22±2 degrees Celsius and 60±5% relative humidity for at least 24 hours prior to testing. Samples are then cut into approximately 250 x 15±0.1 millimeters in either the machine or cross direction with a double-blade strip cutter. The edges of the test specimens should be neatly cut so that no more than three test specimens are cut at the same time.

[0163] The tension / compression testing device is set up by installing a 100 Newton tension load cell, powering on the general-purpose tension / compression testing machine and computer, selecting a predefined measurement method in the software, and setting the test speed to 8 mm / min. The tension load cell is then calibrated and pneumatic grips are attached. The test distance between the pneumatic grips is adjusted to 180 ± 0.5 mm using a steel gauge block, and the distance and force are set to zero.

[0164] The test specimen is then placed straight and centered between the grips, avoiding finger contact with the area being tested. The upper grips are closed and the paper strip is suspended in the open lower grip. The force is set to zero. The paper strip is gently pulled down and then the lower grips are closed, with an initial force of 0.05-0.20 Newtons. As the upper grips move upward, a gradually increasing force is applied until the test specimen breaks. The same procedure is repeated with the remaining test specimens. The result is valid when the test specimen breaks when the grips move apart a distance of more than 10 millimeters. If not, the result is rejected and additional measurements are performed.

[0165] If the available test specimen of homogenized chamomile material is smaller than the sample described in the test according to ISO 1924-2, as described above, the test can be easily scaled down to accommodate the available size of the test specimen.

[0166] One or more sheets of homogenized chamomile material described herein may each individually have a tensile strength at the peak in the tolerance direction of 50 N / m to 400 N / m, or preferably 150 N / m to 350 N / m. Given that sheet thickness affects tensile strength and that batches of sheets may exhibit thickness variations, it may be desirable to normalize values ​​to a particular sheet thickness.

[0167] One or more sheets described herein may each individually have a tensile strength of 100 N / m to 800 N / m, or preferably 280 N / m to 620 N / m, at the peak in the machine direction, normalized to a sheet thickness of 215 μm. The machine direction refers to the direction in which the sheet material is wound onto or unwound from the bobbin and fed into the machine, and the tolerance direction is perpendicular to the machine direction. These values ​​of tensile strength make the sheets and methods described herein particularly suitable for subsequent operations involving mechanical stress.

[0168] Providing a sheet having the above-defined levels of thickness, basis weight, and tensile strength advantageously optimizes the machinability of the sheet to form aerosol-generating substrates and ensures that damage, such as tearing, to the sheet is avoided during high speed processing of the sheet.

[0169] In embodiments of the invention in which the aerosol-generating substrate comprises one or more sheets of homogenized chamomile material, the sheets are preferably in the form of an assembly of one or more sheets. As used herein, the term "assembling" means that the sheets of homogenized chamomile material are convoluted, folded, or otherwise compressed or contracted in a direction substantially transverse to the cylindrical axis of the plug or rod. The step of "assembling" the sheets may be carried out by any suitable means that provides the necessary transverse compression of the sheets.

[0170] As used herein, the term "longitudinal" refers to a direction corresponding to the major longitudinal axis of the aerosol-generating article, extending between the upstream and downstream ends of the aerosol-generating article. During use, air is drawn through the aerosol-generating article in the longitudinal direction. The term "transverse" refers to a direction perpendicular to the longitudinal axis. As used herein, the term "length" refers to the dimension of a component in the longitudinal direction, and the term "width" refers to the dimension of a component in the transverse direction. For example, in the case of a plug or rod having a circular cross-section, the maximum width corresponds to the diameter of the circle.

[0171] As used herein, the term "plug" refers to a generally cylindrical element having a substantially polygonal, circular, oval, or elliptical cross-section. As used herein, the term "rod" refers to a generally cylindrical element of a substantially polygonal cross-section, and preferably a circular, oval, or elliptical cross-section. A rod may have a length equal to or greater than the length of a plug. Typically, a rod has a length greater than the length of a plug. A rod may include one or more plugs, which are preferably aligned longitudinally.

[0172] As used herein, the terms "upstream" and "downstream" describe the relative location of an element (or portion of an element) of an aerosol-generating article with respect to the direction in which aerosol is transported through the aerosol-generating article during use. The downstream end of the airflow path is the end from which the aerosol is delivered to a user of the article.

[0173] One or more sheets of homogenized chamomile material may be gathered transversely to their longitudinal axis and surrounded by a wrapper to form a continuous rod or plug. The continuous rod may be separated into a plurality of individual rods or plugs. The wrapper may be a paper wrapper or a non-paper wrapper, as described in more detail below.

[0174] Alternatively, one or more sheets of homogenized chamomile material may be cut into strands, as mentioned above. In such embodiments, the aerosol-generating substrate comprises multiple strands of homogenized chamomile material. The strands can be used to form plugs. Typically, the width of such strands is at least about 0.2 mm, or at least about 0.5 mm. Typically, the width of such strands is preferably about 5 mm, or about 4 mm, or about 3 mm, or about 1.5 mm or less. For example, the width of the strands can be about 0.25 mm to about 5 mm, or about 0.25 mm to about 3 mm, or about 0.5 mm to about 1.5 mm.

[0175] The length of the strands is preferably greater than about 5 mm, for example, about 5 mm to about 20 mm, or about 8 mm to about 15 mm, or about 12 mm. The strands preferably have substantially the same length as each other. The length of the strands may be determined by the manufacturing process, whereby the rod is cut into shorter plugs, and the length of the strands corresponds to the length of the plugs. The strands are fragile and may break, especially during transition. In such cases, the length of some of the strands may be shorter than the length of the plugs.

[0176] The strands preferably extend substantially longitudinally along the length of the aerosol-generating substrate, aligned with the longitudinal axis. Thus, the strands are preferably aligned substantially parallel to one another. The longitudinal strands of aerosol-generating material are preferably substantially non-coiled.

[0177] The strands of homogenized chamomile material preferably each have a mass-to-surface area ratio of at least about 0.02 milligrams per square millimeter, more preferably at least about 0.05 milligrams per square millimeter. Preferably, the strands of homogenized chamomile material each have a mass-to-surface area ratio of no more than about 0.2 milligrams per square millimeter, more preferably no more than about 0.15 milligrams per square millimeter. The mass-to-surface area ratio is calculated by dividing the mass of the strands of homogenized chamomile material in milligrams by the geometric surface area of ​​the strands of homogenized chamomile material in square millimeters.

[0178] One or more sheets of homogenized chamomile material may be textured by crimping, embossing, or perforation. One or more sheets may be textured before being gathered or before being cut into strands. Preferably, one or more sheets of homogenized chamomile material are crimped prior to gathering so that the homogenized chamomile material can be in the form of a crimped sheet, more preferably a collection of crimped sheets. As used herein, the term "crimped sheet" refers to a sheet having a plurality of substantially parallel ridges or corrugations that are generally aligned along the longitudinal axis of the article.

[0179] In one embodiment, the aerosol-generating substrate may be in the form of a single plug of aerosol-generating substrate. Preferably, the plug of aerosol-generating substrate may comprise multiple strands of homogenized chamomile material. Most preferably, the plug of aerosol-generating substrate may comprise one or more sheets of homogenized chamomile material. Preferably, the one or more sheets of homogenized chamomile material may be crimped to have multiple ridges or corrugations substantially parallel to the cylindrical axis of the plug. This advantageously facilitates assembling the crimped sheets of homogenized chamomile material to form the plug. Preferably, the one or more sheets of homogenized chamomile material may be assembled. Of course, the crimped sheets of homogenized chamomile material may alternatively or additionally have multiple substantially parallel ridges or corrugations that form acute or obtuse angles with respect to the cylindrical axis of the plug. The sheet may be crimped to the extent that the integrity of the sheet is interrupted in a plurality of parallel ridges or corrugations, causing separation of the material and resulting in the formation of pieces, strands or strips of homogenized chamomile material.

[0180] In another embodiment of the aerosol-generating substrate, the homogenized plant material comprises a first plug containing a first homogenized plant material and a second plug containing a second homogenized plant material, the first homogenized plant material and the second homogenized plant material containing different levels of chamomile particles and tobacco particles. For example, the first homogenized plant material may contain, on a dry weight basis, about 50 weight percent to about 75 weight percent chamomile particles, and the second homogenized plant material contains, on a dry weight basis, about 50 weight percent to about 75 weight percent tobacco particles. Generally, according to the present invention, it is preferred that the homogenized plant material in the aerosol-generating substrate contain, on a dry weight basis, at least 2.5 weight percent chamomile particles and up to 70 weight percent tobacco particles.

[0181] In such an arrangement, the first homogenized plant material preferably comprises a first particulate plant material having a higher proportion of chamomile particles than the second homogenized plant material, which may be a homogenized tobacco material substantially free of chamomile particles.

[0182] The first homogenized plant material may be in the form of one or more sheets, and the second homogenized plant material may be in the form of one or more sheets.

[0183] Optionally, the aerosol-generating substrate may include one or more plugs. Preferably, the substrate may include a first plug and a second plug, and the first homogenized plant material may be located within the first plug and the second homogenized plant material may be located within the second plug.

[0184] Two or more plugs may extend end-to-end in abutting relationship to form a rod. Two plugs may be longitudinally positioned with a gap between them, thereby creating a cavity within the rod. The plugs may be in any suitable arrangement within the rod.

[0185] For example, in a preferred arrangement, a downstream plug containing a predominant proportion of chamomile particles may abut an upstream plug containing a predominant proportion of tobacco particles to form a rod. Alternative configurations are also contemplated in which the upstream and downstream positions of each plug are altered relative to one another. Alternative configurations are also contemplated in which a third homogenized plant material contains different proportions of chamomile and tobacco particles to form a third plug. When two or more plugs are provided, the homogenized plant material may be provided in the same form in each plug or in different forms in each plug, i.e., aggregated or shredded. One or more plugs may optionally be individually or together packaged in a thermally conductive sheet material, as described below.

[0186] The first plug may comprise one or more sheets of the first homogenized plant material, and the second plug may comprise one or more sheets of the second homogenized plant material. The combined length of the plugs may be about 10 mm to about 40 mm, preferably about 10 mm to about 15 mm, and more preferably about 12 mm. The first plug and the second plug may be the same length or may have different lengths. If the first plug and the second plug have the same length, the length of each plug may preferably be about 6 mm to about 20 mm. The second plug may preferably be longer than the first plug to provide a desired ratio of tobacco particles to chamomile particles in the substrate. Generally, the substrate preferably comprises, on a dry weight basis, 0 to 75 weight percent tobacco particles and 2.5 to 75 weight percent chamomile particles. The second plug is preferably at least 40 to 50 percent longer than the first plug.

[0187] When the first homogenized plant material and the second homogenized plant material are in the form of one or more sheets, the one or more sheets of the first homogenized plant material and the second homogenized plant material can preferably be a conglomerate of sheets. The one or more sheets of the first homogenized plant material and the second homogenized plant material can preferably be a crimped sheet. It should be understood that all other physical properties described with respect to embodiments in which a single homogenized plant material is present are equally applicable to embodiments in which a first homogenized plant material and a second homogenized plant material are present. Furthermore, it should be understood that descriptions of additives (e.g., binders, lipids, fibers, aerosol formers, humectants, plasticizers, flavors, fillers, aqueous and non-aqueous solvents, and combinations thereof) with respect to embodiments in which a single homogenized plant material is present are equally applicable to embodiments in which a first homogenized plant material and a second homogenized plant material are present.

[0188] In yet another embodiment of the aerosol-generating substrate, the first homogenized plant material is in the form of a first sheet and the second homogenized plant material is in the form of a second sheet, the second sheet at least partially overlying the first sheet.

[0189] The first sheet may be a textured sheet and the second sheet may be a non-textured sheet.

[0190] Both the first and second sheets may be textured sheets.

[0191] The first sheet may be a textured sheet that is textured differently than the second sheet. For example, the first sheet may be crimped and the second sheet may be perforated. Alternatively, the first sheet may be perforated and the second sheet may be crimped.

[0192] Both the first and second sheets may be morphologically differently crimped sheets, for example, the second sheet may be crimped with a different number of crimps per sheet unit width compared to the first sheet.

[0193] The sheets may be assembled to form a plug. The sheets that assemble to form a plug may have different physical dimensions. The width and thickness of the sheets may vary.

[0194] It may be desirable to assemble two sheets, each having a different thickness, or each having a different width. This can vary the physical properties of the plug. This can facilitate the formation of a blended plug of aerosol-generating substrate from sheets of different chemical compositions.

[0195] The first sheet may have a first thickness and the second sheet may have a second thickness that is a multiple of the first thickness, for example, the second sheet may have a thickness that is two or three times the first thickness.

[0196] The first sheet may have a first width and the second sheet may have a second width different from the first width.

[0197] The first sheet and the second sheet may be disposed in an overlapping relationship before or at the time of being assembled together. The sheets may have the same width and thickness. The sheets may have different thicknesses. The sheets may have different widths. The sheets may be differently textured.

[0198] If it is desired that both the first and second sheets be textured, the sheets may be textured simultaneously before being assembled. For example, the sheets may be placed in overlapping relationship and passed through a texturing means such as a pair of crimping rollers. Suitable apparatus and processes for simultaneous crimping are described with reference to Figure 2 of WO-A-2013 / 178766. In a preferred embodiment, a second sheet of the second homogenized plant material is placed on top of the first sheet of the first homogenized plant material, and the combined sheets assemble to form a plug of aerosol-generating substrate. Optionally, the sheets may be crimped together prior to assembly to facilitate assembly.

[0199] Alternatively, each sheet may be textured separately and then assembled together into a plug. For example, if the two sheets have different thicknesses, it may be desirable to crimp the first sheet differently relative to the second sheet.

[0200] It will be understood that all other physical properties described with respect to embodiments in which a single homogenized plant material is present are equally applicable to embodiments in which a first homogenized plant material and a second homogenized plant material are present. Additionally, it will be understood that the descriptions of additives (e.g., binders, lipids, fibers, aerosol formers, humectants, plasticizers, flavors, fillers, aqueous and non-aqueous solvents, and combinations thereof) with respect to embodiments in which a single homogenized plant material is present are equally applicable to embodiments in which a first homogenized plant material and a second homogenized plant material are present.

[0201] The homogenized plant material used in the aerosol-generating substrate according to the present invention may be produced by a variety of methods, including papermaking, casting, dough reconstitution, extrusion or any other suitable process.

[0202] The homogenized chamomile material is preferably in the form of "cast leaf." The term "cast leaf" refers to a sheet product made by a casting process based on casting a slurry containing plant particles (e.g., chamomile particles, or a mixture of tobacco and chamomile particles) and a binder (e.g., guar gum) onto a support surface (e.g., a belt conveyor), drying the slurry, and removing the dried sheet from the support surface. An example of a casting or cast leaf process is described, for example, in U.S. Pat. No. 5,724,998 for making cast leaf tobacco. In the cast leaf process, particulate plant material is mixed with a liquid component, typically water, to form a slurry. Other added components in the slurry may include fibers, binders, and aerosol formers. The particulate plant material may be agglomerated in the presence of a binder. The slurry is cast onto a support surface and dried to form a sheet of homogenized chamomile material.

[0203] In certain preferred embodiments, the homogenized chamomile material used in articles according to the present invention is generated by casting. Homogenized chamomile material made by a casting process typically comprises agglomerated particulate plant material.

[0204] The cast leaf process advantageously preserves most of the flavor by retaining virtually all of the soluble fraction within the plant material, and also avoids the energy-intensive papermaking process.

[0205] In one preferred embodiment of the present invention, a mixture containing particulate plant material, water, a binder, and an aerosol former is formed to form a homogenized chamomile material. A sheet is formed from the mixture, and the sheet is then dried. The mixture is preferably an aqueous mixture. As used herein, "dry weight" refers to the weight of the particulate non-water components relative to the total weight of all non-water components in the mixture, expressed as a percentage. The composition of an aqueous mixture may be referred to by "dry weight percent," which refers to the weight of the non-water components relative to the weight of the entire aqueous mixture, expressed as a percentage.

[0206] The mixture may be a slurry. As used herein, a "slurry" is a homogenized aqueous mixture having a relatively low dry weight. Preferably, the slurry used in the methods herein may have a dry weight of 5 to 60 percent.

[0207] Alternatively, the mixture may be a dough. As used herein, a "dough" is an aqueous mixture having a relatively high dry weight. Preferably, the dough used in the methods herein may have a dry weight of at least 60 percent, more preferably at least 70 percent.

[0208] Slurries containing greater than 30 percent dry weight and dough are preferred in certain embodiments of the process of the present invention.

[0209] The step of mixing the particulate plant material, water, and other optional ingredients can be carried out by any suitable means. For low-viscosity mixtures, i.e., some slurries, mixing is preferably carried out using a high-energy mixer or a high-shear mixer. Such mixing breaks down and uniformly distributes the various phases of the mixture. For high-viscosity mixtures, i.e., some lumps, a kneading process can be used to uniformly distribute the various phases of the mixture.

[0210] The method according to the present invention may further comprise a step of vibrating the mixture to distribute the various components. Vibrating the mixture, i.e., for example, vibrating the tank or silo in which the homogenized mixture is located, may help homogenize the mixture, especially if the mixture is a low-viscosity mixture, i.e., some slurries. When vibration is performed in addition to mixing, shorter mixing times may be required to homogenize the mixture to the optimum target value for casting.

[0211] When the mixture is a slurry, the web of homogenized chamomile material is preferably formed by a casting process that involves casting the slurry onto a support surface, such as a belt conveyor. The method for producing homogenized chamomile material includes drying the cast web to form a sheet. The cast web may be dried for a suitable length of time at room temperature or at an ambient temperature of at least about 60°C, more preferably at least about 80°C. The cast web is preferably dried at an ambient temperature not exceeding 200°C, more preferably not exceeding about 160°C. For example, the cast web may be dried at a temperature of about 60°C to about 200°C, or about 80°C to about 160°C. The moisture content of the dried sheet is preferably about 5% to about 15%, based on the total weight of the sheet. The sheet may then be removed from the support surface after drying. The cast sheet has tensile strength such that it can be mechanically manipulated and wound onto or unwound from a bobbin without breakage or deformation.

[0212] If the mixture is a dough mass, the dough mass may be extruded into sheets, strands, or strips prior to drying the extruded mixture. Preferably, the dough mass can be extruded into a sheet. The extruded mixture may be dried at room temperature or at a temperature of at least about 60°C, more preferably at least about 80°C, for a suitable length of time. The extruded mixture is preferably dried at ambient temperatures not exceeding 200°C, more preferably not exceeding about 160°C. For example, the extruded mixture may be dried at temperatures of about 60°C to about 200°C, or about 80°C to about 160°C. The moisture content of the extruded mixture after drying is preferably about 5 percent to about 15 percent, based on the total weight of the sheet. As a result of the significantly lower moisture content relative to webs formed from slurries, sheets formed from dough mass require less drying time and / or lower drying temperatures.

[0213] After drying the sheet, the method may optionally include coating a nicotine salt onto the sheet, preferably together with an aerosol former, as described in the disclosure of WO-A-2015 / 082652.

[0214] After drying the sheet, the method according to the present invention may optionally include cutting the sheet into strands, pieces, or strips to form the aerosol-generating substrate described above. The strands, pieces, or strips may be joined together using suitable means to form a rod of aerosol-generating substrate. In the formed rod of aerosol-generating substrate, the strands, pieces, or strips may be substantially aligned, for example, along the longitudinal axis of the rod. Alternatively, the strands, pieces, or strips may be randomly oriented within the rod.

[0215] The method according to the present invention may optionally further comprise winding the sheet onto a bobbin after the drying step. The present invention further provides an alternative papermaking method for producing a sheet of homogenized plant material in the form of plant "paper." Plant paper refers to a reconstituted plant sheet formed by a process of extracting plant material with a solvent to produce an extract of soluble plant compounds and an insoluble residue of fibrous plant material, and recombining the extract with the insoluble residue. The extract may optionally be concentrated or further processed before being recombined with the insoluble residue. The insoluble residue may optionally be purified and combined with additional plant fiber before being recombined with the extract. In the method according to the present invention, the plant material comprises chamomile particles, optionally combined with tobacco particles.

[0216] More specifically, the method for producing plant paper involves a first step of mixing plant material with water to form a dilute suspension, which primarily contains discrete cellulose fibers. The suspension has a lower viscosity and a higher water content than the slurries produced in casting processes. This first step may involve soaking, optionally in the presence of an alkali such as sodium hydroxide, and optionally the application of heat.

[0217] The method further includes a second step of separating the suspension into an insoluble portion containing the insoluble residue of the fibrous plant material and a liquid or aqueous portion containing the soluble plant compounds. Water remaining in the insoluble residue of the fibrous plant material can be drained through a screen acting as a sieve to allow a web of randomly woven fibers to be laid down. Water can be further removed from this web by pressing with rollers, optionally with the assistance of suction or vacuum.

[0218] After the aqueous portion and water are removed, the insoluble residue is formed into a sheet. Preferably, a generally flat, uniform sheet of plant fiber is formed.

[0219] Preferably, the method further comprises concentrating the extract of soluble plant compounds removed from the sheet and adding the concentrated extract to the sheet of insoluble residue of fibrous plant material to form a sheet of homogenized plant material. Alternatively or additionally, soluble plant material or concentrated plant material from another process may be added to the sheet. The extract or concentrated extract may be from a different variety of the same species of plant, or from a different species of plant.

[0220] This process has been used with tobacco to make reconstituted tobacco products, also known as tobacco paper, as described in U.S. Pat. No. 3,860,012. The same process can be used with one or more plants to generate paper-like sheet materials, such as chamomile paper sheets.

[0221] In certain preferred embodiments, the homogenized plant material used in the articles according to the invention is produced by the paper-making process defined above. In such embodiments, the homogenized chamomile material is in the form of chamomile paper.

[0222] Homogenized tobacco material or homogenized chamomile material produced by such a process is called tobacco paper or chamomile paper. Homogenized plant material produced by a papermaking process can be distinguished by the presence of multiple fibers throughout the material, which are visible to the eye or under an optical microscope, especially when the paper is moistened with water. In contrast, homogenized plant material produced by a casting process contains fewer fibers than paper and tends to separate into a slurry when moistened. Mixed tobacco-chamomile paper refers to homogenized plant material produced by such a process using a mixture of tobacco material and chamomile material.

[0223] In embodiments in which the aerosol-generating substrate comprises a combination of chamomile particles and tobacco particles, the aerosol-generating substrate may comprise one or more sheets of chamomile paper and one or more sheets of tobacco paper. The chamomile paper and tobacco paper sheets may be interleaved or overlapped with one another before being assembled to form a rod. Optionally, the sheets may be crimped. Alternatively, the chamomile paper and tobacco paper sheets may be cut into strands, strips, or pieces and then combined to form a rod. The relative amounts of tobacco and chamomile in the aerosol-generating substrate may be adjusted by varying the number of tobacco and chamomile sheets, respectively, or the amount of chamomile and tobacco strands, strips, or pieces, respectively, within the rod.

[0224] For example, the number or amount of tobacco and chamomile sheets or strands may be adjusted to provide a chamomile to tobacco ratio of about 1:4, or about 1:9, or about 1:30.

[0225] Other known processes which may be applied to the production of homogenized plant material are, for example, dough reconstitution processes of the type described in U.S. Pat. No. 3,894,544, and extrusion processes of the type described in GB-A-983,928. Generally, the density of homogenized plant material produced by extrusion and dough reconstitution processes is greater than the density of homogenized plant material produced by casting processes.

[0226] Preferably, the aerosol-generating substrate of an aerosol-generating article according to the present invention comprises at least about 200 mg of homogenized plant material, more preferably at least about 250 mg of homogenized plant material, more preferably at least about 300 mg of homogenized plant material.

[0227] The aerosol-generating article according to the present invention comprises a rod comprising an aerosol-generating substrate in one or more plugs. The rod of aerosol-generating substrate may have a length of from about 5 mm to about 120 mm. For example, the rod may preferably have a length of from about 10 mm to about 45 mm, more preferably from about 10 mm to 15 mm, and most preferably about 12 mm. In alternative embodiments, the rod preferably has a length of from about 30 mm to about 45 mm, or from about 33 mm to about 41 mm. When the rod is formed from a single plug of aerosol-generating substrate, the plug has the same length as the rod.

[0228] The rods of aerosol-generating substrates may have an outer diameter of about 5 mm to about 10 mm depending on their intended use. For example, in some embodiments, the rods may have an outer diameter of about 5.5 mm to about 8 mm, or about 6.5 mm to about 8 mm. The "outer diameter" of the rod of aerosol-generating substrate corresponds to the diameter of the rod including any wrapper.

[0229] The rod of aerosol-generating substrate in an aerosol-generating article according to the present invention is preferably surrounded by one or more wrappers along at least a portion of its length. The one or more wrappers may comprise a paper wrapper, a non-paper wrapper, or both. Suitable paper wrappers for use in certain embodiments of the present invention are known in the art and include, but are not limited to, cigarette paper and filter plug wrap. Suitable non-paper wrappers for use in certain embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco material. Homogenized tobacco wrappers are particularly suitable for use in embodiments in which the aerosol-generating substrate comprises one or more sheets of homogenized chamomile material formed from particulate plant material, the particulate plant material containing chamomile particles in combination with a low weight percentage of tobacco particles, such as between 20 weight percent and 0 weight percent tobacco particles, on a dry weight basis.

[0230] In certain embodiments of the present invention, the aerosol-generating substrate is surrounded along at least a portion of its length by a thermally conductive sheet material, such as a metal foil, e.g., aluminum foil or metalized paper. The metal foil or metalized paper serves the purpose of rapidly conducting heat throughout the aerosol-generating substrate. Additionally, the metal foil or metalized paper may serve to prevent the aerosol-generating substrate from igniting if a consumer attempts to light it. Furthermore, during use, the metal foil or metalized paper may prevent odors generated as the outer wrapper heats from entering the aerosol generated from the aerosol-generating substrate. For example, this may be problematic for aerosol-generating articles having an aerosol-generating substrate that is externally heated during use to generate the aerosol. Alternatively, or additionally, the metalized wrapper may be used to facilitate detection or recognition of the aerosol-generating article when inserted into an aerosol-generating device during use. The metal foil or metalized paper may contain metal particles, such as iron particles.

[0231] The one or more wrappers surrounding the aerosol-generating substrate preferably have an overall thickness of from about 0.1 mm to about 0.9 mm.

[0232] The inner diameter of the rod of the aerosol-generating substrate is preferably from about 3 mm to about 9.5 mm, more preferably from about 4 mm to about 7.5 mm, and even more preferably from about 5 mm to about 7.5 mm. "Inner diameter" corresponds to the diameter of the rod of the aerosol-generating substrate, measured with the wrapper still in place, not including the thickness of the wrapper. Aerosol-generating articles according to the present invention also include, but are not limited to, cartridges or hookah consumables.

[0233] The aerosol-generating article according to the present invention may optionally include at least one hollow tube immediately downstream of the aerosol-generating substrate. One function of the tube is to position the aerosol-generating substrate toward the distal end of the aerosol-generating article so that it can contact the heating element. The tube acts to prevent the aerosol-generating substrate from being forced along the aerosol-generating article toward other downstream elements when the heating element is inserted into the aerosol-generating substrate. The tube also acts as a spacer element to separate the downstream elements from the aerosol-generating substrate. The tube may be made of any material, such as cellulose acetate, polymer, cardboard, or paper.

[0234] The aerosol-generating article according to the present invention optionally includes one or more spacers or aerosol cooling elements downstream of the aerosol-generating substrate and immediately downstream of the hollow tube. During use, the aerosol formed by volatile compounds emitted from the aerosol-generating substrate passes through and is cooled by the aerosol cooling element before being inhaled by the user. The low temperature allows the vapor to condense into an aerosol. The spacer or aerosol cooling element may be a hollow tube, such as a hollow cellulose acetate tube or cardboard tube, similar to the one immediately downstream of the aerosol-generating substrate. The spacer may be a hollow tube with an outer diameter equal to that of the hollow cellulose acetate tube, but with a smaller or larger inner diameter. In one embodiment, the paper-wrapped aerosol cooling element includes one or more longitudinal channels made of any suitable material, such as metal foil, foil-laminated paper, polymeric sheets, preferably made of synthetic polymers, and substantially non-porous paper or cardboard. In some embodiments, the paper-wrapped aerosol cooling element may include one or more sheets made of a material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose acetate (CA), paper laminated with a polymer sheet, and aluminum foil. Alternatively, the aerosol cooling element may be made of woven fibers or nonwoven filaments of a material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), and cellulose acetate (CA). In a preferred embodiment, the aerosol cooling element is a crimped and aggregated polylactic acid sheet wrapped within filter paper. In another preferred embodiment, the aerosol cooling element includes longitudinal channels and is made of woven filaments of a synthetic polymer, such as polylactic acid filaments, wrapped in paper.

[0235] The aerosol-generating article according to the present invention may further comprise a filter or mouthpiece downstream of the aerosol-generating substrate and the hollow acetate tube, spacer, or aerosol cooling element. The filter may comprise one or more filtering materials for removing particulate components, gaseous components, or a combination thereof. Suitable filtering materials are known in the art and include, but are not limited to, fibrous filtering materials such as cellulose acetate tow and paper; adsorbents such as activated alumina, zeolites, molecular sieves, and silica gel; biodegradable polymers including polylactic acid (PLA), Matabi®, hydrophobic viscose fibers, and bioplastics; and combinations thereof. The filter may be located at the downstream end of the aerosol-generating article. The filter may be a cellulose acetate filter plug. In one embodiment, the filter is approximately 7 mm long, but may also have a length of approximately 5 mm to approximately 10 mm.

[0236] The aerosol-generating article according to the present invention may further comprise a mouth-end cavity at the downstream end of the article. The mouth-end cavity may be defined by one or more wrappers extending downstream from the filter or mouthpiece. Alternatively, the mouth-end cavity may be defined by a separate tubular element provided at the downstream end of the aerosol-generating article.

[0237] The aerosol-generating article according to the present invention preferably further comprises a ventilation zone provided at a location along the aerosol-generating article, for example, the aerosol-generating article may be provided at a location along a hollow tube provided downstream of the aerosol-generating substrate.

[0238] In a preferred embodiment of the present invention, the aerosol-generating article comprises an aerosol-generating substrate, at least one hollow tube downstream of the aerosol-generating substrate, and a filter downstream of the at least one hollow tube. Optionally, the aerosol-generating article further comprises an oral end cavity at the downstream end of the filter. Preferably, a ventilation zone is provided at a location along the at least one hollow tube.

[0239] In one particularly preferred embodiment having this configuration, the aerosol-generating substrate has a length of about 33 mm and an outer diameter of about 5.5 mm to 6.7 mm, and the aerosol-generating substrate contains about 340 mg of homogenized chamomile material in the form of multiple strands, the homogenized chamomile material containing about 14 weight percent glycerol on a dry weight basis. In this embodiment, the aerosol-generating article has an overall length of about 74 mm and includes a cellulose acetate tow filter having a length of about 10 mm and an oral end cavity defined by a hollow tube having a length of about 6 to 7 mm. The aerosol-generating article includes a hollow tube downstream of the aerosol-generating substrate, the hollow tube having a length of about 25 mm, and a ventilation zone provided therein.

[0240] Aerosol-generating articles according to the present invention may have an overall length of at least about 30 mm, or at least about 40 mm. The overall length of the aerosol-generating article may be less than 90 mm, or less than about 80 mm.

[0241] In one embodiment, the aerosol-generating article has an overall length of about 40 mm to about 50 mm, preferably about 45 mm. In another embodiment, the aerosol-generating article has an overall length of about 70 mm to about 90 mm, preferably about 80 mm to about 85 mm. In another embodiment, the aerosol-generating article has an overall length of about 72 mm to about 76 mm, preferably about 74 mm.

[0242] The aerosol-generating article may have an outer diameter of about 5 mm to about 8 mm, preferably about 6 mm to about 8 mm. In one embodiment, the aerosol-generating article has an outer diameter of about 7.3 mm.

[0243] The aerosol-generating article according to the present invention may further comprise one or more aerosol modification elements. The aerosol modification element may provide an aerosol modifier. As used herein, the term aerosol modifier is used to describe any substance that, in use, modifies one or more characteristics or properties of the aerosol that passes through the filter. Suitable aerosol modifiers include, but are not limited to, agents that impart a flavor or aroma to the aerosol that passes through the filter in use, or agents that remove flavor from the aerosol that passes through the filter in use.

[0244] The aerosol modifier may be one or more of water or liquid flavorings. The water or moisture may modify the sensory experience of the user, for example, by moistening the generated aerosol, which may provide a cooling effect to the aerosol and reduce the perception of harshness experienced by the user. The aerosol modifier may be in the form of a flavor delivery element for delivering one or more liquid flavorings. Alternatively, liquid flavorings can be added directly to the homogenized plant material, for example, by adding flavor to the slurry or ingredients during the production of the homogenized plant material, or by spraying the liquid flavorings onto the surface of the homogenized plant material.

[0245] The one or more liquid flavoring agents may include any flavor compound or plant extract suitable for releasably disposing in liquid form within the flavor delivery element to enhance the flavor of the aerosol generated during use of the aerosol-generating article. Liquid or solid flavoring agents may also be disposed directly on the material forming the filter, such as cellulose acetate tow. Suitable flavors or flavoring agents include, but are not limited to, menthol, mint (such as peppermint and Dutch spice), chocolate, licorice, citrus and other fruit flavors, gamma octalactone, vanillin, ethyl vanillin, breath freshening flavors, spice flavors (such as cinnamon), methyl salicylate, linalool, eugenol, bergamot oil, geranium oil, lemon oil, cannabis oil, and tobacco flavor. Other suitable flavors may include flavor compounds selected from the group consisting of acids, alcohols, esters, aldehydes, ketones, pyrazines, combinations or blends thereof, and the like.

[0246] The aerosol modifier may be an adsorbent material, such as activated carbon, that removes certain components of the aerosol passing through the filter, thereby altering the taste and aroma of the aerosol.

[0247] The one or more aerosol modification elements may be located downstream of or within the aerosol-generating substrate. The aerosol-generating substrate may include a homogenized chamomile material and an aerosol modification element. In various embodiments, the aerosol modification element may be disposed adjacent to the homogenized chamomile material or embedded in the homogenized chamomile material. Typically, the aerosol modification element may be located downstream of the aerosol-generating substrate, most typically within an aerosol cooling element, a filter of the aerosol-generating article, e.g., within a filter plug, or within a cavity, preferably within a cavity between filter plugs. The one or more aerosol modification elements may be in the form of one or more of threads, capsules, microcapsules, beads, or polymeric matrix materials, or a combination thereof.

[0248] Where the aerosol modifying element is in the form of a thread, the thread may be formed from paper, such as a filter plug wrap, and the thread may be loaded with at least one aerosol modifier and located within the body of the filter, as described in WO-A-2011 / 060961. Other materials that can be used to form the thread include cellulose acetate and cotton.

[0249] Where the aerosol modifying element is in the form of a capsule, the capsule may be a frangible capsule located within a filter, the inner core of the capsule containing the aerosol modifier that can be released upon rupture of the outer shell of the capsule when the filter is subjected to an external force, as described in WO-A-2007 / 010407, WO-A-2013 / 068100 and WO-A-2014 / 154887. The capsule may be located within a filter plug or cavity, or within a cavity between filter plugs.

[0250] When the aerosol modifying element is in the form of a polymeric matrix material, the polymeric matrix material releases the flavorant when the aerosol-generating article is heated, such as when the polymeric matrix is ​​heated above the melting point of the polymeric matrix material, as described in WO-A-2013 / 034488. Typically, such a polymeric matrix material may be located within beads within the aerosol-generating substrate. Alternatively, or additionally, the flavorant may be confined within a domain of the polymeric matrix material and releasable from the polymeric matrix material upon compression of the polymeric matrix material. Preferably, the flavorant is released upon compression of the polymeric matrix material at a force of about 15 Newtons. Such a flavor modifying element may provide sustained release of the liquid flavorant over a force range of at least 5 Newtons, such as 5N to 20N, as described in WO 2013 / 068304. Typically, such a polymeric matrix material may be located within beads within a filter.

[0251] The aerosol-generating article may comprise a combustible heat source and an aerosol-generating substrate downstream of the combustible heat source, the aerosol-generating substrate being as described above in relation to the first aspect of the invention.

[0252] For example, the substrates described herein may be used in heated aerosol-generating articles of the type disclosed in WO-A-2009 / 022232, which comprise a combustible carbon-based heat source, an aerosol-generating substrate downstream of the combustible heat source, and a thermally conductive element surrounding and in contact with a rear portion of the combustible carbon-based heat source and an adjacent front portion of the aerosol-generating substrate, although it will be appreciated that the substrates described herein may also be used in heated aerosol-generating articles with combustible heat sources having other configurations.

[0253] The present invention provides an aerosol-generating system comprising an aerosol-generating device including a heating element and an aerosol-generating article for use in the aerosol-generating device, the aerosol-generating article comprising the aerosol-generating substrate described above.

[0254] In a preferred embodiment, the aerosol-generating substrates described herein may be used in heated aerosol-generating articles for use in electrically operated aerosol-generating systems in which the aerosol-generating substrate of the heated aerosol-generating article is heated by an electrical heat source.

[0255] For example, the aerosol-generating substrates described herein may be used in heated aerosol-generating articles of the type disclosed in EP-A-0 822 760.

[0256] The heating element of such an aerosol-generating device may be in any suitable form that conducts heat. Heating of the aerosol-generating substrate may be achieved internally, externally, or both. Preferably, the heating element may be a heater blade or pin adapted to be inserted into the substrate so that the substrate is heated from the inside. Alternatively, the heating element may partially or completely surround the substrate and heat the substrate circumferentially from the outside.

[0257] The aerosol-generating system may be an electrically operated aerosol-generating system equipped with an induction heating device. The induction heating device typically includes an induction source configured to be coupled to the susceptor, which may be provided externally or internally to the aerosol-generating substrate. The induction source generates an alternating electromagnetic field, which induces magnetization or eddy currents in the susceptor. The susceptor may heat as a result of hysteresis losses or induced eddy currents, which heat the susceptor through ohmic or resistive heating.

[0258] The electrically operated aerosol-generating system including an induction heating device also includes an aerosol-generating article having an aerosol-generating substrate and a susceptor in thermal proximity to the aerosol-generating substrate. Typically, the susceptor is in direct contact with the aerosol-generating substrate, and heat is transferred from the susceptor to the aerosol-generating substrate primarily by conduction. Examples of electrically operated aerosol-generating systems including an induction heating device and an aerosol-generating article having a susceptor are described in WO-A1-95 / 27411 and WO-A1-2015 / 177255.

[0259] The susceptor may be a plurality of susceptor particles that can be deposited on or embedded within the aerosol-generating substrate. When the aerosol-generating substrate is in the form of one or more sheets, the plurality of susceptor particles may be deposited on or embedded within the one or more sheets. For example, the susceptor particles are fixed by the substrate in sheet form and remain in their initial position. Preferably, the susceptor particles can be uniformly distributed throughout the homogenized chamomile material of the aerosol-generating substrate. Due to the particulate nature of the susceptor, heat is generated according to the distribution of the particles within the sheet of homogenized chamomile material of the substrate. Alternatively, susceptors in the form of one or more sheets, strips, pieces, or rods can also be placed next to the homogenized chamomile material or embedded in the homogenized chamomile material. In one embodiment, the aerosol-forming substrate includes one or more susceptor strips. In another embodiment, the susceptor is present within the aerosol-generating device.

[0260] The susceptor may have a heat loss greater than 0.05 Joules / kilogram, preferably greater than 0.1 Joules / kilogram. Heat loss is the capacity of the susceptor to transfer heat to surrounding materials. Because the susceptor particles are preferably uniformly distributed within the aerosol-generating substrate, uniform heat loss from the susceptor particles is achieved, thereby generating a uniform heat distribution within the aerosol-generating substrate and resulting in a uniform temperature distribution within the aerosol-generating article. It has been found that a specific minimum heat loss of 0.05 Joules / kilogram in the susceptor particles allows the aerosol-generating substrate to be heated to a substantially uniform temperature to provide aerosol generation. In such embodiments, the average temperature reached within the aerosol-generating substrate is preferably between about 200°C and about 240°C.

[0261] Reducing the risk of overheating the aerosol-generating substrate can be achieved by using a susceptor material with a Curie temperature, which allows the heating process due to hysteresis losses to reach only a certain maximum temperature. The susceptor may have a Curie temperature between about 200°C and about 450°C, preferably between about 240°C and about 400°C, for example, about 280°C. When the susceptor material reaches its Curie temperature, it changes magnetic properties. At the Curie temperature, the susceptor material changes from a ferromagnetic to a paramagnetic phase. At this point, heating due to energy losses caused by the orientation of the ferromagnetic domains ceases. Thereafter, further heating is primarily based on the formation of eddy currents, so that the heating process is automatically reduced once the Curie temperature of the susceptor material is reached. The susceptor material and its Curie temperature are preferably matched to the composition of the aerosol-generating substrate to achieve optimal temperature and temperature distribution within the aerosol-generating substrate for optimal aerosol generation.

[0262] In some preferred embodiments of the aerosol-generating article according to the present invention, the susceptor is made of ferrite. Ferrite is a ferromagnetic material with high magnetic permeability and is particularly suitable as a susceptor material. The primary component of ferrite is iron. Other metallic components (e.g., zinc, nickel, manganese) or non-metallic components (e.g., silicon) may be present in varying amounts. Ferrite is a relatively inexpensive, commercially available material. Ferrite is available in particulate form within the size range of the particles used in the particulate plant material forming the homogenized plant material according to the present invention. The particles are preferably fully sintered ferrite powders, such as FP160, FP215, or FP350 from PPT (Indiana, USA).

[0263] In certain embodiments of the present invention, an aerosol-generating system comprises an aerosol-generating article including an aerosol-generating substrate as defined above, a source of aerosol former, and a means for vaporizing the aerosol former, preferably a heating element as described above. The source of aerosol former may be a refillable or replaceable reservoir present on the aerosol-generating device. The reservoir is physically separate from the aerosol-generating article, and the generated vapor is directed through the aerosol-generating article. The vapor contacts the aerosol-generating substrate, which releases volatile compounds, such as nicotine and flavorants, in the particulate plant material to form an aerosol. Optionally, to assist in the vaporization of the compounds in the aerosol-generating substrate, the aerosol-generating system may further comprise a heating element, preferably coordinated with the aerosol former, for heating the aerosol-generating substrate. However, in certain embodiments, the heating element used to heat the aerosol-generating article is separate from the heater that heats the aerosol former.

[0264] The present invention further provides an aerosol produced upon heating of an aerosol-generating substrate, as defined above, wherein the aerosol comprises specific amounts and ratios of characteristic compounds derived from chamomile particles as defined above.

[0265] According to the present invention, the aerosol comprises bisabolol oxide A in an amount of at least 0.1 micrograms per aerosol puff, a Tonghaos isomer in an amount of at least 0.1 micrograms per aerosol puff, and α-bisabolol in an amount of at least 0.05 micrograms per aerosol puff, wherein the aerosol puff has a volume of 55 milliliters when generated by a smoking machine. For purposes of the present invention, a "puff" is defined as the volume of aerosol emitted from an aerosol-generating substrate upon heating and collected for analysis, and the aerosol puff has a puff volume of 55 milliliters generated by a smoking machine. Accordingly, any reference herein to an aerosol "puff" is understood to refer to a 55 milliliter puff unless otherwise specified.

[0266] The ranges shown define the total amount of each component measured in a 55 milliliter puff of aerosol. The aerosol may be generated from an aerosol-generating substrate using any suitable means and may be trapped and analyzed as described above to identify and measure the amounts of characteristic compounds within the aerosol. For example, a "puff" may correspond to a 55 milliliter puff measured in a smoking machine, such as that used in the Health Canada test method described herein.

[0267] Preferably, aerosols according to the present invention contain at least about 1 microgram of bisabolol oxide A per aerosol puff, more preferably at least about 2.5 micrograms of bisabolol oxide A per aerosol puff. Alternatively, or additionally, the aerosol generated from the aerosol-generating substrate contains at most about 10 micrograms of bisabolol oxide A per aerosol puff, preferably at most about 8 micrograms of bisabolol oxide A per aerosol puff, and more preferably at most about 5 micrograms of bisabolol oxide A per aerosol puff. For example, the aerosol generated from the aerosol-generating substrate may contain from about 0.1 micrograms to about 10 micrograms of bisabolol oxide A per aerosol puff, or from about 1 microgram of bisabolol oxide A per aerosol puff to about 8 micrograms of bisabolol oxide A per aerosol puff, or from about 2.5 micrograms to about 5 micrograms of bisabolol oxide A per aerosol puff.

[0268] Aerosols according to the present invention preferably contain at least about 1 microgram of Tonghaos isomer per aerosol puff, and more preferably at least about 2.5 micrograms per aerosol puff. Alternatively or additionally, the aerosol generated from the aerosol-generating substrate preferably contains at most about 10 micrograms of Tonghaos isomer per aerosol puff, more preferably at most about 8 micrograms of Tonghaos isomer per aerosol puff, and even more preferably at most about 5 micrograms of Tonghaos isomer per aerosol puff. For example, the aerosol generated from the aerosol-generating substrate may contain from about 0.1 microgram to about 10 micrograms of Tonghaos isomer per aerosol puff, or from about 1 microgram to about 8 micrograms of Tonghaos isomer per aerosol puff, or from about 2.5 micrograms to about 5 micrograms of Tonghaos isomer per aerosol puff.

[0269] Preferably, the aerosols according to the present invention contain at least about 1 microgram of α-bisabolol per aerosol puff, more preferably at least about 2.5 micrograms of α-bisabolol per aerosol puff. Alternatively, or additionally, the aerosol generated from the aerosol-generating substrate preferably contains at most about 10 micrograms of α-bisabolol per aerosol puff, more preferably at most about 8 micrograms of α-bisabolol per aerosol puff, and even more preferably at most about 5 micrograms of α-bisabolol per aerosol puff. For example, the aerosol generated from the aerosol-generating substrate may contain from about 0.05 micrograms to about 10 micrograms of α-bisabolol per aerosol puff, or from about 1 microgram to about 8 micrograms of α-bisabolol per aerosol puff, or from about 2.5 micrograms to about 5 micrograms of α-bisabolol per aerosol puff.

[0270] According to the present invention, the aerosol composition is such that the amount of Tonghaos isomer per aerosol puff is preferably at least about 0.75 times the amount of bisabolol oxide A per aerosol puff. Thus, the ratio of Tonghaos isomer to bisabolol oxide A in the aerosol is preferably at least about 0.75:1. Preferably, the aerosol composition is such that the amount of Tonghaos isomer per aerosol puff is at least the same as the amount of bisabolol oxide A per aerosol puff.

[0271] According to the present invention, the aerosol composition is such that the amount of Tonghaos isomer per aerosol puff is preferably at least equal to the amount of α-bisabolol per aerosol puff.Therefore, the ratio of Tonghaos isomer to α-bisabolol in the aerosol is preferably at least about 1:1.Preferably, the aerosol composition is such that the amount of Tonghaos isomer per aerosol puff is at least 1.5 times the amount of α-bisabolol per aerosol puff.

[0272] A defined ratio of Tonghaos isomers to bisabolol oxide A and α-bisabolol characterizes aerosols derived from chamomile particles. In contrast, the ratio of Tonghaos isomers to bisabolol oxide A and α-bisabolol in aerosols generated from chamomile essential oil will be significantly different.

[0273] Aerosols according to the present invention preferably further comprise at least about 0.1 milligrams of aerosol former per aerosol puff, more preferably at least about 0.2 milligrams of aerosol per aerosol puff, and even more preferably at least about 0.3 milligrams of aerosol former per aerosol puff. Preferably, the aerosols comprise at most 0.6 milligrams of aerosol former per aerosol puff, more preferably at most 0.5 milligrams of aerosol former per aerosol puff, and even more preferably at most 0.4 milligrams of aerosol former per aerosol puff. For example, the aerosols may comprise between about 0.1 milligrams and about 0.6 milligrams of aerosol former per aerosol puff, or between about 0.2 milligrams and about 0.5 milligrams of aerosol former per aerosol puff, or between about 0.3 milligrams and about 0.4 milligrams of aerosol former per aerosol puff. These values ​​are based on a puff volume of 55 milliliters, as defined above.

[0274] Suitable aerosol formers for use in the present invention are described above.

[0275] The aerosol generated from the aerosol-generating substrate of the present invention preferably further comprises at least about 2 micrograms of nicotine per aerosol puff, more preferably at least about 20 micrograms of nicotine per aerosol puff, and even more preferably at least about 40 micrograms of nicotine per aerosol puff. The aerosol preferably comprises at most about 200 micrograms of nicotine per aerosol puff, more preferably at most about 150 micrograms of nicotine per aerosol puff, and even more preferably at most about 75 micrograms of nicotine per aerosol puff. For example, the aerosol may comprise from about 2 micrograms to about 200 micrograms of nicotine per aerosol puff, or from about 20 micrograms to about 150 micrograms of nicotine per aerosol puff, or from about 40 micrograms to about 75 micrograms of nicotine per aerosol puff. These values ​​are based on a puff volume of 55 milliliters, as defined above. In some embodiments of the present invention, the aerosol may contain zero micrograms of nicotine.

[0276] Alternatively or additionally, the aerosols according to the present invention may optionally further comprise at least about 0.5 milligrams of cannabinoid compound per aerosol puff, more preferably at least about 1 milligram of cannabinoid compound per aerosol puff, and even more preferably at least about 2 milligrams of cannabinoid compound per aerosol puff. Preferably, the aerosol comprises up to about 5 milligrams of cannabinoid compound per aerosol puff, more preferably up to about 4 milligrams of cannabinoid compound per aerosol puff, and even more preferably up to about 3 milligrams of cannabinoid compound per aerosol puff. For example, the aerosol may comprise from about 0.5 milligrams to about 5 milligrams of cannabinoid compound per aerosol puff, or from about 1 milligram to about 4 milligrams of cannabinoid compound per aerosol puff, or from about 2 milligrams to about 3 milligrams of cannabinoid compound per aerosol puff. In some embodiments of the present invention, the aerosol may contain zero micrograms of cannabinoid compounds. These values ​​are based on a puff volume of 55 milliliters, as defined above.

[0277] Preferably the cannabinoid compound is selected from CBD and THC, more preferably the cannabinoid compound is CBD.

[0278] Carbon monoxide may also be present in aerosols according to the invention and may be measured and used to further characterize the aerosol. Oxides of nitrogen, such as nitric oxide and nitrogen dioxide, may also be present in aerosols and may be measured and used to further characterize the aerosol.

[0279] Aerosols according to the present invention containing characteristic compounds from chamomile particles can be formed from particles having a mass median aerodynamic diameter (MMAD) ranging from about 0.01 to 200 microns, or from about 1 to 100 microns. When the aerosol contains nicotine as described above, the aerosol preferably contains particles having a MMAD ranging from about 0.1 to about 3 microns to optimize delivery of nicotine from the aerosol.

[0280] The mass median aerodynamic diameter (MMAD) of an aerosol refers to the particle dynamic diameter at which half of the aerosol's particulate mass is occupied by particles with an aerodynamic diameter larger than the MMAD and half by particles with an aerodynamic diameter smaller than the MMAD. The aerodynamic diameter is the mass of a particle that has the same settling velocity as the particle being characterized, 1 g / cm. 3 is defined as the diameter of a spherical particle having a density of

[0281] The mass median aerodynamic diameter of the aerosol according to the present invention can be determined according to Schaller et al., "Evaluation of the Tobacco Heating System 2.2., Section 2.8, Part 2: Chemical composition, genotoxicity, cytotoxicity and physical properties of the aerosol," Regul. Toxicol. and Pharmacol., 81 (2016) S27-S47.

[0282] As defined above, the present invention further provides an aerosol-generating article comprising an aerosol-generating substrate, wherein the aerosol-generating substrate comprises homogenized plant material, and upon heating the aerosol-generating substrate in accordance with Test Method A, an aerosol generated from the aerosol-generating substrate comprises bisabolol oxide A in an amount of at least 0.1 micrograms per aerosol puff, Tonghaos isomer in an amount of at least 0.1 micrograms per aerosol puff, and α-bisabolol in an amount of at least 0.05 micrograms per aerosol puff, and the aerosol puff has a volume of 55 milliliters when generated by a smoking machine.

[0283] For purposes of the present invention, a "puff" is defined as the volume of aerosol emitted from an aerosol-generating substrate upon heating and collected for analysis, with an aerosol puff having a puff volume of 55 milliliters generated by a smoking machine. Accordingly, any reference herein to an aerosol "puff" is understood to refer to a 55 milliliter puff unless otherwise specified. The ranges provided define the total amount of each component measured in a 55 milliliter puff of aerosol. The aerosol may be generated from an aerosol-generating substrate using any suitable means and may be trapped and analyzed as described above to identify and measure the amount of characteristic compounds within the aerosol. For example, a "puff" may correspond to a 55 milliliter puff measured in a smoking machine, such as that used in the Health Canada test method described herein.

[0284] Preferably, the amount of Tonghaos isomer per aerosol puff is at least 0.75 times the amount of bisabolol oxide A per aerosol puff, and more preferably, is at least equal to the amount of bisabolol oxide A per aerosol puff.

[0285] Preferably, the amount of Tonghaos isomer per aerosol puff is at least the same as the amount of α-bisabolol per aerosol puff, and more preferably is at least 1.5 times the amount of α-bisabolol per aerosol puff.

[0286] The present invention also provides an aerosol-generating substrate formed from homogenized plant material comprising chamomile particles, an aerosol former, and a binder, as defined above, the aerosol-generating substrate comprising at least 20 micrograms of bisabolol oxide A per gram of substrate, on a dry weight basis; at least 100 micrograms of Tonghaosu isomer per gram of substrate, on a dry weight basis; and at least 15 micrograms of α-bisabolol per gram of substrate, on a dry weight basis.

[0287] Below is provided a non-exhaustive list of non-limiting examples, any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0288] Example 1 1. An aerosol-generating article comprising an aerosol-generating substrate, the aerosol-generating substrate comprising a homogenized chamomile material, the homogenized chamomile material comprising chamomile particles, an aerosol former, and a binder, the aerosol-generating substrate comprising: at least 20 micrograms of bisabolol oxide A per gram of substrate on a dry weight basis; At least 100 micrograms of Tonghaos isomer per gram of substrate on a dry weight basis; and at least 15 micrograms of α-bisabolol per gram of substrate on a dry weight basis. Example 2 The aerosol-generating article of Example 1, wherein the amount of Tonghaos isomer per gram of substrate is at least four times the amount of bisabolol oxide A per gram of substrate. Example 3 An aerosol-generating article as described in Example 1 or Example 2, wherein the amount of Tonghaos isomer per gram of substrate is at least 5 times the amount of α-bisabolol per gram of substrate. Example 4 The aerosol-generating article of Example 1, Example 2 or Example 3, wherein the aerosol-generating substrate comprises, on a dry weight basis, 20 micrograms to 1000 micrograms of bisabolol oxide A per gram of substrate. Example 5 5. The aerosol-generating article of any one of Examples 1 to 4, wherein the aerosol-generating substrate comprises, on a dry weight basis, 100 micrograms to 4500 micrograms of Tonghaosu isomer per gram of substrate. Example 6 6. An aerosol-generating article according to any one of Examples 1 to 5, wherein the aerosol-generating substrate comprises, on a dry weight basis, from 15 micrograms to 1000 micrograms of α-bisabolol per gram of substrate. Example 7 When the aerosol-generating substrate was heated using Test Method A, at least 5 micrograms of bisabolol oxide A per gram of substrate on a dry weight basis; At least 5 micrograms of Tonghaos isomer per gram of substrate on a dry weight basis; An aerosol-generating article according to any one of Examples 1 to 6, which generates an aerosol comprising at least 3 micrograms of α-bisabolol per gram of substrate on a dry weight basis. Example 8 8. The aerosol-generating article of Example 7, wherein upon heating of the aerosol-generating substrate in accordance with Test Method A, an aerosol is generated comprising at most 250 micrograms of bisabolol oxide A per gram of substrate on a dry weight basis. Example 9 The aerosol-generating article of Example 7 or Example 8, wherein heating the aerosol-generating substrate in accordance with Test Method A generates an aerosol containing up to 250 micrograms of Tonghaos isomer per gram of substrate on a dry weight basis. Example 10 The aerosol-generating article of Example 7, Example 8, or Example 9, wherein heating the aerosol-generating substrate in accordance with Test Method A generates an aerosol containing up to 200 micrograms of α-bisabolol per gram of substrate on a dry weight basis. Example 11 An aerosol-generating article according to any one of Examples 7 to 10, wherein heating of the aerosol-generating substrate by Test Method A generates an aerosol containing 0 micrograms of nicotine per gram of substrate. Example 12 Under Health Canada's mechanical smoking regimen, heating of the aerosol-generating substrate in the THS2.2 holder at least 5 micrograms of bisabolol oxide A per gram of substrate on a dry weight basis; At least 5 micrograms of Tonghaos isomer per gram of substrate on a dry weight basis; An aerosol-generating article according to any one of Examples 1 to 6, which generates an aerosol comprising at least 3 micrograms of α-bisabolol per gram of substrate on a dry weight basis. Example 13 An aerosol-generating article according to any one of Examples 1 to 12, wherein the homogenized chamomile material comprises at least 2.5 weight percent chamomile particles on a dry weight basis. Example 14 An aerosol-generating article according to any one of Examples 1 to 13, wherein the homogenized chamomile material comprises up to 50 weight percent chamomile particles on a dry weight basis. Example 15 An aerosol-generating article according to any one of Examples 1 to 14, wherein the homogenized chamomile material further comprises up to about 75 weight percent tobacco particles on a dry weight basis. Example 16 An aerosol-generating article according to any one of Examples 1 to 15, wherein the homogenized chamomile material further comprises tobacco particles, and the weight ratio of chamomile particles to tobacco particles is 1:4 or less. Example 17 The aerosol-generating article of Example 15 or Example 16, wherein the homogenized chamomile material comprises, on a dry weight basis, 5 weight percent to 20 weight percent chamomile particles and 55 weight percent to 70 weight percent tobacco particles. Example 18 An aerosol-generating article according to any one of Examples 1 to 17, wherein the homogenized chamomile material contains substantially no nicotine. Example 19 An aerosol-generating article as described in Examples 1-17, wherein the aerosol-generating substrate further comprises at least 0.1 milligrams of nicotine per gram of substrate on a dry weight basis. Example 20 20. The aerosol-generating article of example 19, wherein the aerosol-generating substrate contains, on a dry weight basis, from 1 milligram to 20 milligrams of nicotine per gram of substrate. Example 21 An aerosol-generating article according to any one of Examples 1 to 20, wherein the chamomile particles have a D95 value of about 50 microns or more and about 400 microns or less. Example 22 An aerosol-generating article according to any one of Examples 1 to 21, wherein the chamomile particles have a D5 value of about 10 microns or more and about 50 microns or less. Example 23 An aerosol-generating article according to any one of Examples 1 to 22, wherein the chamomile particles are intentionally pulverized. Example 24 An aerosol-generating article according to any one of Examples 1 to 23, wherein 100 percent of the chamomile particles have a diameter of 300 microns or less. Example 25 An aerosol-generating article according to any one of Examples 1 to 24, wherein the homogenized chamomile material comprises up to 75 weight percent particulate plant material, and the particulate plant material comprises chamomile particles. Example 26 The aerosol-generating article of any one of Examples 1 to 25, wherein the homogenized chamomile material has an aerosol former content of 5 weight percent to 30 weight percent on a dry weight basis. Example 27 An aerosol-generating article according to any one of Examples 1 to 26, wherein the binder is selected from gums such as guar gum, xanthan gum, gum arabic and locust bean gum, cellulosic binders such as hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose and ethyl cellulose, organic acids such as starch, alginic acid, conjugate base salts of organic acids such as sodium alginate, polysaccharides such as agar and pectin, and combinations thereof. Example 28 28. The aerosol-generating article of any one of Examples 1 to 27, wherein the binder comprises guar gum. Example 29 An aerosol-generating article according to any one of Examples 1 to 28, wherein the homogenized chamomile material comprises, on a dry weight basis, 1 weight percent to 10 weight percent binder. Example 30 An aerosol-generating article according to any one of Examples 1 to 29, wherein the homogenized chamomile material further comprises fibers. Example 31 An aerosol-generating article as described in Example 30, wherein the fibers have a length of greater than 400 micrometers. Example 32 The aerosol-generating article of example 30 or example 31, wherein the fibers are present in an amount of about 2 weight percent to about 15 weight percent, based on the dry weight of the aerosol-generating substrate. Example 33 The aerosol-generating article of example 30 or example 31, wherein the fibers are present in an amount of at least 30 percent by weight, based on the dry weight of the aerosol-generating substrate. Example 34 An aerosol-generating article described in any one of Examples 1 to 33, wherein the homogenized chamomile material comprises chamomile particles, about 5 weight percent to about 30 weight percent of an aerosol former, and about 1 weight percent to about 10 weight percent of a binder, on a dry weight basis. Example 35 35. The aerosol-generating article of example 34, wherein the homogenized chamomile material further comprises between about 2 weight percent and about 15 weight percent fiber. Example 36 The aerosol-generating article of Example 34 or Example 35, wherein the binder is guar gum. Example 37 An aerosol-generating article according to any one of Examples 1 to 36, wherein the homogenized chamomile material is in the form of one or more sheets. Example 38 38. The aerosol-generating article of Example 37, wherein each of the one or more sheets has a thickness of 100 micrometers to 600 micrometers. Example 39 One or more sheets, each of 100 g / m 2 ~300g / m 2 39. The aerosol-generating article of Example 38, having a mass of 1000 grammes. Example 40 One or more sheets, each of which is 0.3 g / m 3 ~1.3g / m 3 40. The aerosol-generating article of Example 38 or Example 39, having a density of Example 41 41. The aerosol-generating article of Example 38, Example 39 or Example 40, wherein each of the one or more sheets has a peak cross-direction tensile strength of from 50 N / m to 400 N / m. Example 42 41. The aerosol-generating article of any one of Examples 38 to 40, wherein each of the one or more sheets has a peak machine direction tensile strength of from 100 N / m to 800 N / m. Example 43 The aerosol-generating article of any one of Examples 38 to 42, wherein the one or more sheets are in the form of an assembly of one or more sheets. Example 44 An aerosol-generating article according to any one of Examples 1 to 36, wherein the homogenized chamomile material is in the form of multiple strands. Example 45 An aerosol-generating article as described in Example 44, wherein the strands have a width of at least 0.2 mm. Example 46 An aerosol-generating article as described in Example 44 or Example 45, wherein the plurality of strands are aligned with the longitudinal axis and extend substantially longitudinally along the length of the aerosol-generating substrate. Example 47 The aerosol-generating article of Example 44, Example 45, or Example 46, wherein each of the plurality of strands has a mass-to-surface area ratio of at least 0.02 milligrams per square millimeter. Example 48 An aerosol-generating article as described in any one of Examples 1 to 47, wherein the homogenized chamomile material in the aerosol-generating substrate is in the form of a cast leaf. Example 49 An aerosol-generating article as described in any one of Examples 1 to 47, wherein the homogenized chamomile material in the aerosol-generating substrate is in the form of chamomile paper. Example 50 When the aerosol-generating substrate is heated by test method A, the aerosol generated from the aerosol-generating substrate is bisabolol oxide A in an amount of at least 0.1 micrograms per aerosol puff; Tonghaosu isomer in an amount of at least 0.1 micrograms per aerosol puff; alpha-bisabolol in an amount of at least 0.05 micrograms per aerosol puff; An aerosol-generating article as described in any one of Examples 1 to 49, wherein the aerosol puff has a volume of 55 milliliters as produced by a smoking machine, the amount of Tonghaos isomer per aerosol puff is at least 0.75 times the amount of bisabolol oxide A per aerosol puff, and the amount of Tonghaos isomer per aerosol puff is at least equal to the amount of α-bisabolol per aerosol puff. Example 51 An aerosol-generating article comprising an aerosol-generating substrate, the aerosol-generating substrate comprising homogenized chamomile material comprising chamomile particles, from about 5 weight percent to about 30 weight percent of an aerosol former, and from about 1 weight percent to about 10 weight percent of a binder, on a dry weight basis. Example 52 52. The aerosol-generating article of Example 51, wherein the homogenized chamomile material further comprises an essential oil, preferably chamomile essential oil. Example 53 An aerosol-generating article as described in Example 51 or Example 52, wherein the homogenized chamomile material further comprises tobacco particles. Example 54 An aerosol-generating article described in any one of Examples 51 to 53, wherein the homogenized chamomile material contains at least 2.5 weight percent chamomile particles on a dry weight basis. Example 55 1. An aerosol-generating substrate comprising a homogenized chamomile material comprising chamomile particles, an aerosol former, and a binder, the aerosol-generating substrate comprising: at least 20 micrograms of bisabolol oxide A per gram of substrate on a dry weight basis; At least 100 micrograms of Tonghaos isomer per gram of substrate on a dry weight basis; and at least 15 micrograms of α-bisabolol per gram of substrate on a dry weight basis. Example 56 1. An aerosol generating system comprising: an aerosol generating device having a heating element; An aerosol-generating system comprising the aerosol-generating article according to any one of Examples 1 to 54. Example 57 57. The aerosol-generating system of Example 56, wherein the heating element is a heater blade adapted to be inserted into the aerosol-generating substrate. Example 57 The aerosol is bisabolol oxide A in an amount of at least 0.1 micrograms per aerosol puff; Tonghaosu isomer in an amount of at least 0.1 micrograms per aerosol puff; alpha-bisabolol in an amount of at least 0.05 micrograms per aerosol puff; An aerosol produced upon heating of the aerosol-generating substrate described in Example 55, wherein the aerosol puff has a volume of 55 milliliters as produced by a smoking machine, the amount of Tonghaos isomer per gram of substrate is at least 0.75 times the amount of bisabolol oxide A per gram of substrate, and the amount of Tonghaos isomer per gram of substrate is at least equal to the amount of α-bisabolol per gram of substrate. Example 58 1. A method of making an aerosol-generating substrate, comprising: forming a slurry comprising chamomile particles, water, an aerosol former, a binder, and optionally tobacco particles; casting or extruding the slurry in the form of a sheet or strand; and drying the sheet or strand at 80 degrees Celsius to 160 degrees Celsius. Example 59 The method of example 58, wherein the slurry is cast onto a support surface and allowed to dry to form a sheet of cast leaves. Example 60 1. A method of making an aerosol-generating substrate, comprising: forming a dilute suspension comprising chamomile particles, water, and optionally tobacco particles; separating the suspension into an insoluble portion and a liquid extract; forming the insoluble portion into a sheet; concentrating the liquid extract and applying the concentrated liquid extract to a sheet to form chamomile paper.

[0289] Specific embodiments will now be further described, by way of example only, with reference to the accompanying drawings in which: [Brief explanation of the drawings]

[0290] [Figure 1] FIG. 1 illustrates a first embodiment of the substrate of the aerosol-generating article described herein. [Figure 2] FIG. 2 illustrates an aerosol generating system comprising an aerosol generating device including an aerosol-generating article and an electric heating element. [Figure 3] FIG. 3 illustrates an aerosol generating system comprising an aerosol generating device including an aerosol-generating article and a combustible heating element. [Figure 4a] FIG. 4a illustrates a second embodiment of the substrate of the aerosol-generating article described herein. [Figure 4b] FIG. 4b illustrates a second embodiment of the substrate of the aerosol-generating article described herein. [Figure 5] FIG. 5 illustrates a third embodiment of the substrate of the aerosol-generating article described herein. [Figure 6] Figures 6a, 6b, and 6c are cross-sectional views of a filter 1050 further including an aerosol modification element. Figure 6a illustrates an aerosol modification element in the form of a spherical capsule or bead within a filter plug. Figure 6b illustrates an aerosol modification element in the form of a thread within a filter plug. Figure 6c illustrates an aerosol modification element in the form of a spherical capsule within a cavity within the filter. [Figure 7] FIG. 7 is a cross-sectional view of a plug of an aerosol-generating substrate 1020 further including an elongated susceptor element. [Figure 8]FIG. 8 illustrates the experimental setup for collecting aerosol samples that are analyzed to measure characteristic compounds. DETAILED DESCRIPTION OF THE INVENTION

[0291] FIG. 1 illustrates a heated aerosol-generating article 1000 including a substrate as described herein. The article 1000 comprises four elements: an aerosol-generating substrate 1020, a hollow cellulose acetate tube 1030, a spacer element 1040, and a mouthpiece filter 1050. These four elements are sequentially arranged in a coaxial configuration and assembled with cigarette paper 1060 to form the aerosol-generating article 1000. The article 1000 has a mouth end 1012, which a user inserts into the mouth during use, and a distal end 1013 at the opposite end of the article from the mouth end 1012. The embodiment of the aerosol-generating article illustrated in FIG. 1 is particularly suitable for use in an electrically operated aerosol-generating device that includes a heater for heating the aerosol-generating substrate.

[0292] When assembled, article 1000 is approximately 45 millimeters long, has an outer diameter of approximately 7.2 millimeters, and an inner diameter of approximately 6.9 millimeters.

[0293] The aerosol-generating substrate 1020 comprises a plug formed from a sheet of homogenized chamomile material containing chamomile particles, either alone or in combination with tobacco particles.

[0294] Some examples of suitable homogenized chamomile material for forming the aerosol-generating substrate 1020 are shown in Table 1 below (see Samples B-D). The sheet is gathered, crimped, and wrapped with filter paper (not shown) to form a plug. The sheet contains additives, including glycerin as an aerosol former.

[0295] The aerosol-generating article 1000 illustrated in Figure 1 is designed to be engaged with an aerosol-generating device for consumption. Such an aerosol-generating device includes means for heating the aerosol-generating substrate 1020 to a sufficient temperature to form an aerosol. Generally, the aerosol-generating device may include a heating element surrounding the aerosol-generating article 1000 adjacent to the aerosol-generating substrate 1020, or a heating element inserted into the aerosol-generating substrate 1020.

[0296] Upon engaging the aerosol-generating device, a user draws on the mouth end 1012 of the smoking article 1000, causing the aerosol-generating substrate 1020 to heat to a temperature of approximately 375 degrees Celsius. At this temperature, volatile compounds are released from the aerosol-generating substrate 1020. These compounds condense to form an aerosol. The aerosol is drawn through the filter 1050 and into the user's mouth.

[0297] Figure 2 illustrates a portion of an electrically operated aerosol-generating system 2000 utilizing a heating blade 2100 to heat the aerosol-generating substrate 1020 of an aerosol-generating article 1000. The heating blade is mounted within the aerosol-article-receiving chamber of an electrically operated aerosol-generating device 2010. The aerosol-generating device defines a plurality of air holes 2050 for allowing air to flow through the aerosol-generating article 1000. The air flow is indicated by arrows in Figure 2. The aerosol-generating device includes a power source and electronic components, which are not shown in Figure 2. The aerosol-generating article 1000 of Figure 2 is as described with respect to Figure 1.

[0298] In an alternative configuration shown in Figure 3, an aerosol-generating system is shown with a combustible heating element. While item 1000 of Figure 1 is intended to be consumed in conjunction with an aerosol-generating device, item 1001 of Figure 3 includes a combustible heat source 1080 that can be ignited to transfer heat to an aerosol-generating substrate 1020 to form an inhalable aerosol. Combustible heat source 80 can be a charcoal element assembled adjacent to the aerosol-generating substrate at the distal end 13 of rod 11. Elements that are essentially the same as those in Figure 1 are numbered the same.

[0299] 4a and 4b illustrate a second embodiment of a heated aerosol-generating article 4000a, 4000b. The aerosol-generating substrate 4020a, 4020b comprises a first downstream plug 4021 formed from particulate plant material containing chamomile particles and a second upstream plug 4022 formed from particulate plant material containing primarily tobacco particles. A suitable homogenized chamomile material for use in the first downstream plug is shown in Table 1 below as one of Samples A-D. A suitable homogenized tobacco material for use in the second upstream plug is shown in Table 1 below as Sample E. Sample E contains only tobacco particles and is included for comparative purposes only.

[0300] In each plug, the homogenized plant material is in the form of a sheet, which is crimped and rolled onto filter paper (not shown). Both sheets contain an additive, including glycerol as an aerosol former. In the embodiment shown in FIG. 4a, the plugs are joined end-to-end in an abutting relationship to form a rod, each approximately 6 mm long. In a more preferred embodiment (not shown), the second plug is preferably longer than the first plug, e.g., preferably 2 mm longer, more preferably 3 mm longer, such that the second plug is 7 or 7.5 mm long, while the first plug is 5 or 4.5 mm long to provide the desired ratio of tobacco particles to chamomile particles in the substrate. In FIG. 4b, the cellulose acetate tube support element 1030 is omitted.

[0301] 1 are particularly suitable for use in the electrically operated aerosol generating system 2000 with a heater shown in FIG. 2. Elements that are essentially the same as those in FIG. 1 are numbered the same. It will be appreciated by those skilled in the art that a combustible heat source (not shown) may alternatively be used in the second embodiment in place of an electric heating element in a configuration similar to that including combustible heat source 1080 of item 1001 in FIG. 3.

[0302] 5 illustrates a third embodiment of a heated aerosol-generating article 5000. The aerosol-generating substrate 5020 comprises a rod formed from a first sheet of homogenized chamomile material formed from particulate plant material including a proportion of chamomile particles, and a second sheet of homogenized tobacco material including primarily cast leaf tobacco.

[0303] A suitable homogenized chamomile material for use as the first sheet is identified below in Table 1 as one of Samples A through D. A suitable homogenized tobacco material for use as the second sheet is identified below in Table 1 as Sample E. Sample E contains only tobacco particles and is included for comparative purposes only.

[0304] A second sheet is placed on top of the first sheet, and the combined sheets are crimped, assembled, and at least partially wrapped with filter paper (not shown) to form a plug that is a portion of a rod. Both sheets contain an additive, including glycerol, as an aerosol former. Article 5000, similar to article 1000 of FIG. 1, is particularly suitable for use in electrically operated aerosol generating system 2000 with a heater, as shown in FIG. 2. Elements essentially identical to those in FIG. 1 are numbered the same. It will be apparent to those skilled in the art that a combustible heat source (not shown) could alternatively be used in the third embodiment in place of an electric heating element, in a configuration similar to that including combustible heat source 1080 of article 1001 of FIG. 3.

[0305] 6a, 6b, and 6c are cross-sectional views of a filter 1050 further including an aerosol-modifying element. In FIG. 6a, filter 1050 further comprises an aerosol-modifying element in the form of a spherical capsule or bead 605.

[0306] In the embodiment of Figure 6a, capsules or beads 605 are embedded within filter segment 601 and are surrounded on all sides by filter material 603. In this embodiment, the capsule comprises an outer shell and an inner core containing a liquid flavorant. The liquid flavorant is for flavoring the aerosol during use of the aerosol-generating article provided with the filter. The capsule 605 releases at least a portion of the liquid flavorant when the filter is subjected to an external force, for example, by squeezing by the consumer. In the illustrated embodiment, the capsule is generally spherical and has a substantially continuous outer shell containing the liquid flavorant.

[0307] In the embodiment of Figure 6b, the filter segment 601 comprises a plug of filter material 603 and a central flavor-bearing thread 607 extending axially through the plug of filter material 603 parallel to the longitudinal axis of the filter 1050. The central flavor-bearing thread 607 is substantially the same length as the plug of filter material 603 such that the ends of the central flavor-bearing thread 607 are visible at the ends of the filter segment 601. In Figure 6b, the filter material 603 is cellulose acetate tow. The central flavor-bearing thread 607 is formed from twisted filter plug wrap and is loaded with an aerosol modifier.

[0308] In the embodiment of Figure 6c, filter segment 601 comprises two or more plugs 603, 603' of filter material. The plugs of filter material 603, 603' are formed from cellulose acetate so as to be capable of filtering the aerosol provided by the aerosol-generating article. A wrapper 609 is wrapped around and connects the filter plugs 603, 603'. Within cavity 611 is capsule 605, which includes an outer shell and an inner core, the inner core containing a liquid flavorant. Alternatively, the capsule may be similar to the embodiment of Figure 6a.

[0309] 7 is a cross-sectional view of an aerosol-generating substrate 1020 further including elongated susceptor strips 705. The aerosol-generating substrate 1020 comprises a plug 703 formed from a sheet of homogenized chamomile material containing tobacco particles and chamomile particles. The elongated susceptor strips 705 are embedded within the plug 703 and extend longitudinally between the upstream and downstream ends of the plug 703. During use, the elongated susceptor strips 705 heat the homogenized chamomile material by induction heating, as described above. [Example]

[0310] As described above with reference to the figures, different samples of homogenized plant material for use in aerosol-generating substrates according to the present invention can be prepared from aqueous slurries having the compositions shown in Table 1. Sample A contains only chamomile particles and no tobacco particles according to the present invention. Samples B-D contain both chamomile and tobacco particles according to the present invention. Sample E contains only tobacco particles and is included for comparative purposes only.

[0311] The particulate plant material in all samples A-E accounts for approximately 75 percent of the dry weight of the homogenized plant material, while glycerol, guar gum, and cellulose fiber account for the remaining approximately 25 percent of the dry weight of the homogenized plant material. The samples are prepared from aqueous slurries containing 78-79 kg of water per 100 kg of slurry.

[0312] In the tables below, %DWB refers to "dry weight basis," in this case the weight percent calculated relative to the dry weight of the homogenized plant material. Chamomile powder may be formed from dried German chamomile flowers, which may be milled by triple impact milling to a final D95=77.3 microns. [Table 1]

[0313] The slurry may be cast onto a glass plate using a casting bar (0.6 mm) and dried in an oven for 7 minutes at 140 degrees Celsius, followed by a second oven for 30 seconds at 120 degrees Celsius.

[0314] For each of homogenized plant material samples A-E, plugs can be produced from a single continuous sheet of homogenized plant material, each having a width of 100 mm to 125 mm. The individual sheets preferably have a thickness of about 220 microns and a weight of about 206 g / m 2 The homogenized plant material in each plug weighs approximately 316 mg, with a total weight of approximately 322.5 mg. Each sheet has a cut width of approximately 128 mm. The sheets can be crimped to a height of 165 microns to 170 microns, rolled into plugs having a length of approximately 12 mm and a diameter of approximately 7 mm, and surrounded by a paper wrapper. The homogenized plant material in each plug weighs approximately 316 mg, with a total weight of each plug being approximately 322.5 mg.

[0315] For each plug, an aerosol-generating article having a total length of about 45 mm can be formed having a structure as shown in Figure 3, comprising, from the downstream end, an oral end cellulose acetate filter (about 7 mm long), an aerosol spacer (about 18 mm long) comprising a crimped sheet of polylactic acid polymer, a hollow acetate tube (about 8 mm long), and the plug of aerosol-generating substrate.

[0316] For homogenized plant material Sample A, in which chamomile particles comprised 100 percent of the particulate plant material, characteristic compounds were extracted from plugs of homogenized plant material using methanol as detailed above. The extracts were analyzed as described above to confirm the presence of the characteristic compounds and to determine the amounts of the characteristic compounds. The results of this analysis are shown in Table 2 below, where the amounts shown correspond to the amount per aerosol-generating article, and the aerosol-generating substrate of the aerosol-generating article contained 316 mg of homogenized plant material Sample A.

[0317] For comparative purposes, the amount of the characteristic compound present in the particulate plant material (chamomile particles) used to form Sample A is also shown. For the particulate material, the amount shown corresponds to the amount of the characteristic compound in a sample of particulate plant material having a weight corresponding to the total weight of particulate plant material in the aerosol-generating article containing 316 mg of Sample A.

[0318] For each of samples B through D containing a certain proportion of chamomile particles, the amount of characteristic compounds can be estimated based on the values ​​in Table 2 by assuming that the amount is present in proportion to the weight of the chamomile particles. [Table 2]

[0319] Mainstream aerosols from aerosol-generating articles incorporating aerosol-generating substrates formed from homogenized plant material samples A through E may be generated in accordance with Test Method A, as defined above. For each sample, the generated aerosol may be trapped and analyzed.

[0320] As detailed above, according to Test Method A, an aerosol-generating article can be tested using a commercially available Philip Morris Products SA IQOS® heat-not-burn device Tobacco Heating System 2.2 Holder (THS2.2 Holder). The aerosol-generating article is heated under Health Canada's mechanical smoking regimen for 30 puffs with a puff volume of 55 ml, a puff duration of 2 seconds, and 30 seconds between puffs (as described in ISO / TR19478-1:2014).

[0321] The aerosol generated during the smoking test is collected on a Cambridge filter pad and extracted with a liquid solvent. Figure 10 shows a suitable apparatus for generating and collecting aerosol from an aerosol-generating article.

[0322] The aerosol generating device 111 shown in Figure 10 is a commercially available tobacco heating device (iQOS). The mainstream aerosol content generated during the Health Canada smoking test detailed above is collected in an aerosol collection chamber 113 on an aerosol collection line 120. The glass fiber filter pad 140 is a 44 mm Cambridge glass fiber filter pad (CFP) that complies with ISO 4387 and ISO 3308.

[0323] For LC-HRAM-MS analysis : The extraction solvent 170, 170a, in this case methanol and internal standard (ISTD) solution, is present in each microimpinger 160, 160a at a volume of 10 mL. The cold baths 161, 161a each contain dry ice-isopropyl ether to maintain the microimpingers 160, 160a, respectively, at approximately −60° C. The gas-vapor phase is trapped within the extraction solvent 170, 170a as the aerosol is bubbled through the microimpingers 160, 160a. The combined solutions from the two microimpingers are separated in step 181 as the impinger-trapped gas-vapor phase solution 180.

[0324] The CFP and impinger-trapped gas-vapor phase solution 180 are combined in a clean Pyrex® tube in step 190. In step 200, all particulate matter is extracted from the CFP using the impinger-trapped gas-vapor phase solution 180 (containing methanol as a solvent) by thorough shaking (to disintegrate the CFP), stirring for 5 minutes, and finally centrifugation (4500 g, 5 minutes, 10°C). An aliquot (300 μL) of the total reconstituted aerosol extract 220 was transferred to a silanized chromatography vial and diluted with methanol (700 μL) because the extraction solvent 170, 170a already contained the internal standard (ISTD) solution. The vial was closed and mixed for 5 minutes using an Eppendorf ThermoMixer (5°C, 2000 rpm).

[0325] For compound identification, aliquots (1.5 μL) of the diluted extract were injected and analyzed by LC-HRAM-MS in both full scan and data-dependent fragmentation modes.

[0326] Regarding GCxGC-TOFMS analysis: As mentioned above, when preparing samples for GCxGC-TOFMS experiments, different solvents are appropriate for the extraction and analysis of polar, nonpolar, and volatile compounds separated from whole aerosols. The experimental setup is identical to that described for LC-HRAM-MS sample collection, with the exceptions noted below.

[0327] Non-polar and polar Extraction solvent 171, 171a is present in a volume of 10 mL and is an 80:20 v / v mixture of dichloromethane and methanol, also containing a retention index marker (RIM) compound and a stable isotope-labeled internal standard (ISTD). Cold baths 162, 162a each contain a dry ice-isopropanol mixture to maintain microimpingers 160, 160a, respectively, at approximately −78°C. A gas-vapor phase is trapped within extraction solvent 171, 171a as the aerosol is bubbled through microimpingers 160, 160a. The combined solutions from the two microimpingers are separated in step 182 as impinger-trapped gas-vapor phase solution 210.

[0328] non-polar The CFP and impinger-trapped gas-vapor phase solution 210 are combined in a clean Pyrex® tube in step 190. In step 200, all particulate matter is extracted from the CFP using impinger-trapped gas-vapor phase solution 210 (containing dichloromethane and methanol as solvents) by thorough shaking (to break down the CFP), stirring for 5 minutes, and finally centrifugation (4500 g, 5 minutes, 10° C.) to separate polar and non-polar components of the total aerosol extract 230.

[0329] In step 250, a 10 mL aliquot 240 of the entire aerosol extract 230 was removed. In step 260, a 10 mL aliquot of water was added and the entire sample was shaken and centrifuged. The non-polar fraction 270 was isolated, dried over sodium sulfate, and analyzed by GCxGC-TOFMS in full scan mode.

[0330] polarity ISTD and RIM compounds were added to the polar fraction 280, which was directly analyzed by GCxGC-TOFMS in full scan mode.

[0331] Each smoking replicate (n=3) contains an accumulation of 270% of the entrapped reconstituted non-polar fraction and 280% of the non-polar fraction for each sample.

[0332] Volatile components The entire aerosol was trapped using two microimpingers 160, 160a in series. Extraction solvents 172, 172a, in this case N,N-dimethylformamide (DMF), a retention indicator marker (RIM) compound, and a stable isotope-labeled internal standard (ISTD), were present in each microimpinger 160, 160a at a volume of 10 mL. Cold baths 161, 161a each contained dry ice-isopropanol ether to maintain the microimpingers 160, 160a at approximately -60°C, respectively. The gas-vapor phase was trapped within the extraction solvents 170, 170a as the aerosol was bubbled through the microimpingers 160, 160a. The combined solution from the two microimpingers was separated as a volatile-containing phase 211 in step 183. The volatile-containing phase 211 is analyzed separately from the other phases and injected directly into the GCxGC-TOFMS using cool on-column without further preparation.

[0333] Table 3 below shows the levels of characteristic compounds from chamomile particles in aerosols generated from an aerosol-generating article incorporating Sample A of homogenized plant material containing only chamomile particles. For comparison purposes, Table 3 also shows the levels of characteristic compounds in aerosols generated from an aerosol-generating article incorporating Sample E of homogenized plant material containing only tobacco particles (and therefore not according to the invention). [Table 3]

[0334] Relatively high levels of characteristic compounds were measured in the aerosol generated from Sample A. The ratio of Tonghaos isomer to bisabolol oxide A was greater than or equal to 1, and the ratio of Tonghaos isomer to α-bisabolol was also greater than or equal to 1. Thus, the levels of characteristic compounds indicated the presence of chamomile particles in the sample. In contrast, the tobacco-only Sample E, which was substantially free of chamomile particles, was found to have zero or near-zero levels of characteristic compounds.

[0335] For each of Samples B through D containing a proportion of chamomile particles, the amount of characteristic compound in the aerosol can be estimated based on the values ​​in Table 3 by assuming that the amount is present in proportion to the weight of chamomile particles in the aerosol-generating substrate from which the aerosol was generated.

[0336] Table 4 below compares the levels of certain aerosol components in the aerosol generated from an aerosol-generating article incorporating Sample B (20:80 chamomile to tobacco) with the aerosol generated from the tobacco-only Sample E. The reduction shown is the percentage reduction provided by replacing 20 percent of the tobacco particles in the homogenized material of Sample E with chamomile particles.

[0337] As shown in Table 4, aerosols generated from Sample B, containing 20 weight percent chamomile powder based on the dry weight of the particulate plant material, resulted in reduced levels of formaldehyde and acrolein when compared to the levels of the same compounds in aerosols generated from Sample E, containing 100 weight percent tobacco based on the dry weight of the particulate plant material. Additionally, aerosols generated from Sample B resulted in reduced levels of several polycyclic aromatic hydrocarbons (PAHs), benzo[a]pyrene, benz[a]anthracene, and dibenz[a,h]anthracene, compared to aerosols generated from Sample E.

[0338] In most cases, the reduction in the level of these undesirable aerosol compounds is significantly greater than the expected percentage reduction resulting from replacing 20% ​​of tobacco particles with chamomile particles.Therefore, the combination of chamomile particles and tobacco particles results in an unexpectedly high reduction in the level of these compounds.Therefore, the inclusion of chamomile particles can reduce the level of certain undesirable compounds in aerosol, while providing an aerosol with improved sensory properties. [Table 4]

Claims

1. 1. A heated aerosol-generating article comprising an aerosol-generating substrate, the aerosol-generating substrate comprising a homogenized chamomile material, the homogenized chamomile material comprising, on a dry weight basis, at least 2.5 percent by weight of chamomile particles, an aerosol former, and a binder, the aerosol-generating substrate comprising: at least 20 micrograms of bisabolol oxide A per gram of said substrate on a dry weight basis; at least 100 micrograms of Tonghaos isomer per gram of said substrate on a dry weight basis; at least 15 micrograms of α-bisabolol per gram of said substrate on a dry weight basis; The heated aerosol-generating article further comprises at least one hollow tube immediately downstream of the aerosol-generating substrate.

2. 2. The heated aerosol-generating article of claim 1, wherein the amount of Tonghaos isomer per gram of substrate is at least four times the amount of bisabolol oxide A per gram of substrate, and the amount of Tonghaos isomer per gram of substrate is at least five times the amount of α-bisabolol per gram of substrate.

3. 3. The heated aerosol-generating article according to claim 1, wherein the aerosol-generating substrate further comprises, on a dry weight basis, from 1 milligram to 20 milligrams of nicotine per gram of the substrate.

4. 4. The heated aerosol-generating article of claim 1, wherein the homogenized chamomile material comprises, on a dry weight basis, from 5 to 30 percent by weight of an aerosol former and from 1 to 10 percent by weight of a binder.

5. The heated aerosol-generating article according to any one of claims 1 to 4, wherein the binder comprises guar gum.

6. 6. The heated aerosol-generating article according to claim 1, wherein the homogenized chamomile material further comprises tobacco particles, and the weight ratio of the chamomile particles to the tobacco particles is 1:4 or less.

7. 7. The heated aerosol-generating article according to claim 1, wherein the homogenized chamomile material in the aerosol-generating substrate is in the form of cast leaves.

8. 7. The heated aerosol-generating article according to claim 1, wherein the homogenized chamomile material in the aerosol-generating substrate is in the form of chamomile paper.

9. When the aerosol-generating substrate is heated by Test Method A, at least 5 micrograms of bisabolol oxide A per gram of said substrate on a dry weight basis; at least 5 micrograms of Tonghaos isomer per gram of said substrate on a dry weight basis; The heated aerosol-generating article according to any one of claims 1 to 8, which generates an aerosol comprising at least 3 micrograms of α-bisabolol per gram of the substrate on a dry weight basis.

10. When the aerosol-generating substrate is heated by test method A, the aerosol generated from the aerosol-generating substrate is bisabolol oxide A in an amount of at least 0.1 micrograms per aerosol puff; Tonghaosu isomer in an amount of at least 0.1 micrograms per aerosol puff; α-bisabolol in an amount of at least 0.05 micrograms per aerosol puff; 10. The heated aerosol-generating article of claim 1, wherein the aerosol puff has a volume of 55 milliliters as produced by a smoking machine, the amount of Tonghaos isomer per aerosol puff is at least 0.75 times the amount of bisabolol oxide A per aerosol puff, and the amount of Tonghaos isomer per aerosol puff is at least equal to the amount of α-bisabolol per aerosol puff.

11. 1. An aerosol generating system comprising: an aerosol generating device having a heating element; An aerosol generating system comprising the heated aerosol-generating article according to any one of claims 1 to 10.

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