Aerosol generating article with a wrapper having overlapping regions

Abstract

The aerosol-generating article (10) comprises an aerosol-forming substrate (11) and a wrapper (30) surrounding the aerosol-forming substrate. The wrapper defines an overlap region (41) where the wrapper overlaps itself, the overlap region including a first section (42) and a second section (43) disposed externally on the first section. The second section includes a crease (44) at one end of the wrapper that defines a folded section (45), the folded section being sandwiched between the first and second sections. An exterior adhesive is disposed between the folded section and the second section.

Description

Technical Field

[0001] The present invention relates to an aerosol-generating article comprising an aerosol-forming substrate. The aerosol-generating article can be used to generate an inhalable aerosol upon heating.

Background Art

[0002] Aerosol-generating articles in which an aerosol-forming substrate, such as a tobacco-containing substrate, is heated rather than combusted are known in the art. The aim of such heatable aerosol-generating articles is to reduce potentially harmful by-products generated by the combustion and pyrolysis of tobacco in conventional cigarettes.

[0003] In heatable aerosol-generating articles, the inhalable aerosol is typically generated by heat transfer from a heater to the aerosol-forming substrate. During heating, volatile compounds are released from the aerosol-forming substrate and entrained into air. For example, volatile compounds may pass through or around the vicinity of the aerosol-generating article, or otherwise be entrained in air drawn into the vicinity thereof. As the released volatile compounds cool, they condense to form an aerosol. The aerosol may be inhaled by a user. The aerosol may contain aroma, flavor, nicotine, and other desirable components.

[0004] A heating element may be included in an aerosol-generating device. An aerosol-generating system may be formed by a combination of an aerosol-generating article and an aerosol-generating device.

[0005] A heatable aerosol-generating article may comprise one or more wrappers surrounding at least a portion of the aerosol-generating article. Advantageously, the one or more wrappers prevent a user from contacting the aerosol-forming substrate, which can help maintain a high level of hygiene. The provision of one or more wrappers can also contribute to securing the components of the aerosol-generating article together.

Summary of the Invention

[0006] However, if the wrapper encloses at least a portion of the aerosol-generating article, the wrapper may include at least one free end located on a section of the wrapper where the free ends overlap. This arrangement may be detrimental to the mechanical stability of the aerosol-generating article and may also interfere with the manufacture and handling of the aerosol-generating article.

[0007] Therefore, it is desirable to provide an aerosol generating article that comprises one or more wrappers and has improved mechanical stability. [Means for solving the problem]

[0008] An aerosol-generating article may be provided. The aerosol-generating article may comprise a wrapper surrounding an aerosol-forming substrate. The wrapper may define an overlapping region in which the wrapper overlaps itself, the overlapping region comprising a first section and a second section positioned externally on the first section. The second section may include a fold or crease defining a folded section at one end of the wrapper. The folded section may be sandwiched between the first section and the second section.

[0009] Aerosol-generating articles may be provided, and aerosol-generating articles are, Aerosol-forming substrate and, A wrapper surrounding an aerosol-forming substrate, The wrapper defines an overlapping region in which the wrapper overlaps itself, and the overlapping region includes a first section and a second section positioned externally on the first section. The second section includes a crease or fold that defines the folded section at one end of the wrapper, The folded section is sandwiched between the first and second sections.

[0010] The term “aerosol-generating article” is used herein to mean an article in which an aerosol-forming substrate is heated to generate an inhalable aerosol and deliver it to a consumer. As used herein, the term “aerosol-forming substrate” refers to a substrate having the ability to release volatile compounds that can form aerosols. Such volatile compounds may be released by heating the aerosol-forming substrate. An aerosol-forming substrate is typically part of an aerosol-generating article.

[0011] The aerosol-forming substrate may contain nicotine. The nicotine-containing aerosol-forming substrate may also be a nicotine salt matrix.

[0012] The aerosol-forming substrate may contain a liquid. The aerosol-forming substrate may contain both a solid component and a liquid component. It is preferable that the aerosol-forming substrate contains a solid.

[0013] The aerosol-forming substrate may contain plant-derived materials. The aerosol-forming substrate may contain tobacco. The aerosol-forming substrate may contain tobacco-containing materials that include volatile tobacco-flavored compounds released from the aerosol-forming substrate upon heating. The aerosol-forming substrate may contain non-tobacco materials. The aerosol-forming substrate may contain homogenized plant-derived materials.

[0014] As used herein, the term “aerosol generator” typically refers to a device comprising a heater that interacts with an aerosol-forming substrate of an aerosol-generating article in order to generate an aerosol.

[0015] As used herein in connection with the present invention, the term "rod" is used to refer to a generally cylindrical element having a substantially circular, oval, or elliptical cross-section.

[0016] As used herein, the term “longitudinal axis” refers to the direction corresponding to the main longitudinal axis of the aerosol generating article, extending between the upstream and downstream ends of the aerosol generating article. As used herein, the terms “upstream” and “downstream” describe the relative position of an element (or part of an element) of the aerosol generating article with respect to the direction in which aerosols are transported through the aerosol generating article during use.

[0017] During use, air is drawn through the aerosol-generating article in the longitudinal direction. The term "transverse direction" refers to the direction perpendicular to the longitudinal axis. Any reference to the "cross section" of the aerosol-generating article or its components refers to the transverse section unless otherwise specified.

[0018] The term "length" refers to the dimensions of the components of an aerosol-generating article in the longitudinal direction.

[0019] By providing a folded section at one end of the wrapper, sandwiched between the first and second sections of the wrapper, that end of the wrapper does not become the free end of the second section which overlaps with the first section of the wrapper. Therefore, the folded section can improve the mechanical stability of the aerosol-generating article comprising the wrapper.

[0020] Because the folded section is sandwiched between the first and second sections, it does not introduce significant irregularity to the outer surface of the wrapper. This can be beneficial in facilitating the handling of aerosol-generating articles during manufacturing and transport.

[0021] A configuration in which the folded section is defined by a fold or crease comprised in the second section of the wrapper may be desirable compared to other wrapper configurations comprising a folded section in that it avoids or minimises the size of irregular recesses in the internal space defined by the wrapper. Since the internal space defined by the wrapper may be intended to contain an aerosol-forming substrate, this arrangement may make it possible to reduce the amount of aerosol-forming substrate that needs to be used for manufacturing the aerosol-generating article. The manufacturing process may also be improved, since irregular recesses can make insertion of the aerosol-forming substrate more difficult and time-consuming.

[0022] An inner adhesive may be arranged between the folded section and the first section. An outer adhesive may be arranged between the folded section and the second section. Providing the inner adhesive or the outer adhesive may contribute to improving the mechanical stability of the aerosol-generating article. Where both the inner adhesive and the outer adhesive are provided, a greater improvement in mechanical stability may be achieved.

[0023] The inner adhesive and the outer adhesive may be the same adhesive.

[0024] The folded section may extend over at least about 0.75 millimetres of the perimeter of the aerosol-forming substrate, or over at least about 1 millimetre of the perimeter of the aerosol-forming substrate.

[0025] The folded section may extend over up to about 2.5 millimetres of the perimeter of the aerosol-forming substrate, or over up to about 2 millimetres of the perimeter of the aerosol-forming substrate.

[0026] Preferably, the folded section extends from about 0.75 millimeters to about 2.5 millimeters along the periphery of the aerosol-forming substrate, or from about 0.75 millimeters to about 2 millimeters along the periphery of the aerosol-forming substrate, or from about 1 millimeter to 2.5 millimeters along the periphery of the aerosol-forming substrate. More preferably, the folded section extends from about 1 millimeter to about 2 millimeters along the periphery of the aerosol-forming substrate.

[0027] The folded section may extend over at least about 3 percent of the periphery of the aerosol-forming substrate, or at least about 4 percent of the periphery of the aerosol-forming substrate.

[0028] The folded section may extend over at most about 12 percent of the periphery of the aerosol-forming substrate, or at most about 10 percent of the periphery of the aerosol-forming substrate.

[0029] Preferably, the folded section extends from about 3 percent to about 12 percent of the periphery of the aerosol-forming substrate, or from about 3 percent to about 10 percent of the periphery of the aerosol-forming substrate, or from about 4 percent to about 12 percent of the periphery of the aerosol-forming substrate. More preferably, the folded section extends from about 4 percent to about 10 percent of the periphery of the aerosol-forming substrate.

[0030] The second section may extend over at least about 0.75 millimeters of the periphery of the aerosol-forming substrate, or at least about 1 millimeter of the periphery of the aerosol-forming substrate.

[0031] The second section may extend over at most about 2.5 millimeters of the periphery of the aerosol-forming substrate, or at most about 2 millimeters of the periphery of the aerosol-forming substrate.

[0032] The second section preferably extends over a periphery of the aerosol-forming substrate from about 0.75 mm to about 2.5 mm, or from about 0.75 mm to about 2 mm, or from about 1 mm to about 2.5 mm. More preferably, the second section extends over a periphery of the aerosol-forming substrate from about 1 mm to about 2 mm.

[0033] The second section may extend over at least about 3 percent of the periphery of the aerosol-forming substrate, or at least about 4 percent of the periphery of the aerosol-forming substrate.

[0034] The second section may extend over a maximum of approximately 12 percent of the periphery of the aerosol-forming substrate, or over a maximum of approximately 10 percent of the periphery of the aerosol-forming substrate.

[0035] The second section preferably extends over approximately 3 percent to 12 percent of the periphery of the aerosol-forming substrate, or approximately 3 percent to 10 percent of the periphery of the aerosol-forming substrate, or approximately 4 percent to 12 percent of the periphery of the aerosol-forming substrate. More preferably, the second section extends over approximately 4 percent to 10 percent of the aerosol-forming substrate.

[0036] The periphery of the aerosol-forming substrate can also be called the periphery of the aerosol-forming substrate.

[0037] The wrapper may have a basis weight of approximately 10 grams / square meter to 28 grams / square meter. Preferably, the wrapper may have a basis weight of approximately 10 grams / square meter to 16 grams / square meter.

[0038] This range of basis weight can be beneficial in enabling the formation of folded sections within the wrapper.

[0039] The wrapper may have a porosity of about 30 to about 80 cholesta units. Preferably, the wrapper may have a porosity of about 30 to about 50 cholesta units. Most preferably, the wrapper may have a porosity of 30 to 40 cholesta units.

[0040] The wrapper may have a roughness of approximately 50 Becks to approximately 1000 Becks. More preferably, the wrapper may have a roughness of approximately 100 Becks to approximately 200 Becks.

[0041] Roughness, expressed in Beck seconds, is measured by a standard test using a BEKK Smoothness Tester, which generates a vacuum and measures the time it takes for the vacuum to drop from 50.66 kPa to 48.00 kPa. This test is approved by the international standard ISO 5627.

[0042] The inner adhesive may contain one or more of the following: gum arabic, natural or synthetic resin, starch, and varnish. The outer adhesive may contain one or more of the following: gum arabic, natural or synthetic resin, starch, and varnish. Such adhesives may be useful for providing a robust attachment to the overlapping areas of the wrapper.

[0043] A heating element may be embedded within an aerosol-forming substrate. An embedded heating element is an internal heating element. As used herein, the term “internal heating element” refers to a heating element configured to be inserted into or positioned within an aerosol-forming substrate or flavor substrate.

[0044] An aerosol generating article equipped with a heating element embedded in an aerosol-forming substrate may be advantageous in that an enhanced heat distribution from the heating element to the aerosol-forming substrate can be achieved when the aerosol generating article is in use.

[0045] The heating element may also be a susceptor.

[0046] As used herein, the term “susceptor” refers to an element containing a material capable of converting magnetic energy into heat. A susceptor heats up when it is in a fluctuating magnetic field, such as a fluctuating magnetic field generated by an inductor coil.

[0047] Heating of a susceptor can result from hysteresis losses and / or eddy currents induced within the susceptor, depending on the electrical properties and magnetism of the susceptor material. Hysteresis losses occur in ferromagnetic or ferrimagnetic susceptor materials due to magnetic domains in the material being switched under the influence of a fluctuating electromagnetic field. Eddy currents can be induced if the susceptor material is conductive. In the case of a conductive ferromagnetic or ferrimagnetic susceptor material, heat can be generated by both eddy currents and hysteresis losses. Therefore, depending on the electrical properties and magnetism of the susceptor material, a susceptor may be heated by at least one of hysteresis losses or eddy currents.

[0048] The heating element may be completely surrounded by an aerosol-forming substrate and may extend along the entire length of the aerosol-forming substrate. This may provide an optimized heat distribution within the aerosol-forming substrate when the heating element is heated.

[0049] The susceptor may have a thickness of approximately 35 micrometers to approximately 85 micrometers. The susceptor may have a thickness of approximately 45 micrometers to approximately 75 micrometers. The susceptor may have a thickness of approximately 55 micrometers to approximately 65 micrometers.

[0050] In aerosol-generating articles provided with susceptors having the aforementioned thickness, it has been found that heat generation and heat distribution throughout the entire aerosol-forming substrate can be achieved particularly effectively and efficiently. While we do not wish to be bound by theory, this is likely because such susceptors are adapted to provide optimal heat generation and heat transfer due to their surface area and inductive force. In contrast, thinner susceptors are too easily deformed, failing to maintain the desired shape and orientation within the aerosol-forming substrate during the manufacturing of the aerosol-generating article, resulting in a less homogeneous and less finely tuned heat distribution during use. Simultaneously, thicker susceptors may be more difficult to cut to precise and consistent lengths, which can also affect how accurately the susceptors are provided aligned along the long axis within the aerosol-forming substrate, and therefore potentially affect the homogeneity of the heat distribution within the aerosol-forming substrate. These beneficial effects are particularly noticeable when the susceptor extends fully to the downstream end of the aerosol-forming substrate. This is thought to be because there are no aerosol-forming substrates in the aerosol-forming substrate located downstream of the susceptor, which could potentially contribute to draw-out resistance (RTD), thus essentially minimizing the RTD downstream of the susceptor.

[0051] The susceptor may be an elongated susceptor that is substantially arranged along its long axis within the aerosol-forming substrate.

[0052] When used to describe a susceptor, the term "elongated" means that the susceptor has a length dimension that is greater than its width dimension or thickness dimension, for example, a length dimension greater than twice its width dimension or thickness dimension.

[0053] The susceptor may be positioned substantially along its long axis within the aerosol-forming substrate. This means that the length of the elongated susceptor is positioned approximately parallel to the long axis of the aerosol-forming substrate, for example, within ±10 degrees of parallel to the long axis of the aerosol-forming substrate. The elongated susceptor may be positioned at the radial center within the aerosol-forming substrate and extend along the long axis of the aerosol-forming substrate.

[0054] The susceptor may have substantially the same length as the aerosol-forming substrate.

[0055] The susceptor may be in the form of a pin, rod, strip, or blade.

[0056] The susceptor may have a length of about 5 mm to about 15 mm, for example, about 6 mm to about 12 mm, more preferably about 8 mm to about 10 mm.

[0057] The susceptor may have a width of at least about 1 millimeter, more preferably at least about 2 millimeters. Typically, the susceptor may have a width of up to 8 millimeters, preferably about 6 millimeters or less.

[0058] If the susceptor has a certain cross-section, for example a circular cross-section, it may have a width or diameter of about 1 millimeter to about 5 millimeters.

[0059] If the susceptor has the form of a strip or blade, the strip or blade may have a rectangular cross-section, preferably having a width of about 2 mm to about 8 mm, more preferably about 3 mm to about 6 mm. A susceptor in the form of a blade strip may have a width of about 4 mm.

[0060] The elongated susceptor may have a thickness of about 57 micrometers to about 63 micrometers. More preferably, the elongated susceptor may have a thickness of about 58 micrometers to about 62 micrometers. Most preferably, the elongated susceptor has a thickness of about 60 micrometers.

[0061] The diameter of the aerosol-generating article may be approximately 3 mm to 8 mm.

[0062] The wrapper may have a thickness of about 60 micrometers to about 200 micrometers, preferably about 78 micrometers to about 160 micrometers, more preferably 78 micrometers to about 140 micrometers, more preferably about 100 micrometers to about 140 micrometers, and most preferably about 125 micrometers to about 140 micrometers.

[0063] The thickness of the wrapper within this range can lead to a good balance between the overall thickness of the overlapping area and the thickness of the rest of the wrapper.

[0064] The aerosol-forming substrate may contain one or more of the following: tobacco, nicotine, gel composition, and flavoring agent.

[0065] Advantageously, the gel composition may be solid at room temperature. In this context, “solid” means that the gel has a stable size and shape and does not flow. In this context, room temperature means 25 degrees Celsius. A gel may be defined as a substantially diluted crosslinked system that does not exhibit fluidity in a steady state. On a weight basis, gels may be almost liquid, and nevertheless they behave like solids due to a three-dimensional crosslinking network within the liquid. Crosslinking in the fluid gives the gel its structure (hardness). Thus, a gel may be a dispersion of liquid molecules in a solid, where liquid particles are dispersed in a solid medium.

[0066] Aerosol generation may include a filter positioned along the long axis downstream of the aerosol-forming substrate.

[0067] The term "filter" is used to refer to a section of an aerosol-generating article configured to remove, at least partially, gaseous or particulate phase components, or both, from the mainstream aerosol drawn through the filter.

[0068] The length of the aerosol-generating article may be approximately 30 mm to 100 mm.

[0069] The aerosol-generating article may include a support element positioned downstream of the aerosol-forming substrate.

[0070] The support element is often provided in the form of an annular tube of the filtration material, which is often called a hollow acetate tube. Such a hollow tubular support element is configured to resist the downstream movement of the aerosol-forming substrate during handling of the aerosol-generating article, for example, during the insertion of a heating element into the aerosol-forming substrate. The empty space within the hollow tubular support element may provide an opening for aerosols to flow from the aerosol-forming substrate toward the mouth end of the aerosol-generating article.

[0071] The support element may be positioned immediately downstream of the aerosol-forming substrate.

[0072] If the aerosol-generating article includes a filter and a support element, the filter may be positioned along its longitudinal axis downstream of the support element.

[0073] The filter may be positioned along the long axis immediately downstream of the support element.

[0074] Since the support element may be useful and sufficient to provide customization of the aerosol formed according to the user's preference, the filter may be placed immediately downstream of the support element, i.e., without intermediate components such as an aerosol cooling element. Thus, the aerosol generating article can achieve a reduction in gaseous and particulate phase components while requiring fewer production steps and enabling a more consistent experience.

[0075] However, the aerosol generating article may be equipped with an aerosol cooling element downstream of the support element. Preferably, the aerosol cooling element may be positioned between the support element and the filter.

[0076] As used herein, “aerosol cooling element” refers to a component of an aerosol generating article located downstream of an aerosol-forming substrate, such that aerosols formed by volatile compounds released from the aerosol-forming substrate during use pass through the aerosol cooling element and are cooled by the aerosol cooling element before being inhaled by the consumer. The aerosol cooling element is preferably positioned between the aerosol-forming substrate and the mouthpiece. The aerosol cooling element has a large surface area but generates a low pressure drop. Filters and other mouthpieces that generate a high pressure drop (e.g., filters formed from bundles of fibers) are not considered aerosol cooling elements. Chambers and recesses within the aerosol generating article are not considered aerosol cooling elements.

[0077] The support element may comprise a first hollow tubular segment. The aerosol cooling element may comprise a second hollow tubular segment.

[0078] The aerosol generating article may include a mouthpiece positioned at the downstream end of the aerosol generating article. Providing a mouthpiece may be desirable to facilitate the user's inhalation of the aerosol.

[0079] The aerosol generating article may include an upstream element positioned at the upstream end of the aerosol generating article. This can ensure that, if the aerosol generating article includes a susceptor, consumers cannot accidentally come into contact with the susceptor after it has been heated. If the aerosol generating article includes a susceptor, the provision of the upstream element can advantageously prevent the susceptor from detaching.

[0080] The aerosol-forming substrate may have any suitable cross-sectional shape. For example, the substrate may have a circular, elliptical, stadium-shaped, rectangular, or triangular cross-sectional shape. A circular cross-sectional shape is preferred for the substrate.

[0081] The solid aerosol-forming substrate may include a tobacco plug. The tobacco plug may include one or more of the following: herb leaves, tobacco leaves, tobacco stems, puffed tobacco, and homogenized tobacco, for example, one or more of the following: powder, granules, pellets, fragments, strands, slivers, or sheets. The term “homogenized tobacco material” as used herein means a material formed by agglomerating particulate tobacco. Providing homogenized tobacco material may improve aerosol generation and the nicotine content and flavor profile of the aerosol generated during heating of the aerosol-generating article. Specifically, the process of producing homogenized tobacco involves grinding tobacco leaves, which allows for more effective release of nicotine and flavor during heating. If the tobacco plug includes homogenized tobacco material, the homogenized tobacco material may be in the form of a sheet. As used herein, the term “sheet” means a layered element having a width and length substantially greater than its thickness.

[0082] The solid aerosol-forming substrate may contain homogenized tobacco material. The solid aerosol-forming material may contain fragments, strands, or shards of homogenized tobacco material. The solid aerosol-forming substrate may contain sheets of homogenized tobacco material.

[0083] The aerosol-forming substrate may have a substantially homogeneous composition. The aerosol-forming substrate may have a substantially homogeneous composition at least in the longitudinal direction.

[0084] Homogenized tobacco material sheets may be formed by agglomerating particulate tobacco obtained by crushing or otherwise subdividing one or both of tobacco leaf laminas and tobacco leaf stems. Homogenized tobacco material sheets may contain one or more of the following: tobacco dust, tobacco fine powder, and other particulate tobacco by-products formed during tobacco processing, handling, and transport. Preferably, homogenized tobacco material sheets are formed by a casting process of a type that generally includes casting a slurry containing particulate tobacco and one or more binders onto a conveyor belt or other support surface, drying the cast slurry to form a homogenized tobacco material sheet, and removing the homogenized tobacco material sheet from the support surface.

[0085] The solid aerosol-forming substrate may include an aggregate of homogenized tobacco material sheets. As used herein, the term “gathered” is used to describe sheets that have been rolled up, folded, or compressed or shrunk substantially transversely to the longitudinal axis of a separate aerosol-generating article.

[0086] The aerosol-forming substrate comprises an aggregate of textured sheets of homogenized tobacco material. As used herein, the term “textured sheet” means a sheet that is crumpled, embossed, debossed, perforated, or otherwise deformed. The use of textured sheets of homogenized tobacco material is advantageous in that it facilitates the assembly of sheets of homogenized tobacco material to form an aerosol-forming substrate. The aerosol-forming substrate may comprise an aggregate of textured sheets of homogenized tobacco material that includes multiple spaced indentations, protrusions, perforations, or a combination thereof.

[0087] The aerosol-forming substrate preferably comprises an aggregate of crimped sheets of homogenized tobacco material. As used herein, the term “crimped sheet” means a sheet having a plurality of substantially parallel ridges or wavy shapes. The substantially parallel ridges or wavy shapes preferably extend along or parallel to the longitudinal axis of the aerosol-generating article. This advantageously facilitates the collection of crimped sheets of homogenized tobacco material for forming the aerosol-generating article. However, it is recognized that the crimped sheets of homogenized tobacco material to be included in the aerosol-generating article may have a plurality of substantially parallel ridges or wavy shapes arranged at acute or obtuse angles to the longitudinal axis of the aerosol-generating article.

[0088] The aerosol-forming substrate may contain tobacco-containing materials and non-tobacco-containing materials.

[0089] The aerosol-forming substrate may contain aerosol-forming compounds. The aerosol-forming substrate may contain a single aerosol-forming compound or a combination of two or more aerosol-forming compounds. As used herein, the term “aerosol-forming compound” is used to describe any suitable known compound or mixture of compounds that facilitates aerosol formation during use and is substantially resistant to thermal decomposition at the operating temperature of the aerosol-generating article. Suitable aerosol-forming compounds include, but are not limited to, polyhydric alcohols (such as propylene glycol, triethylene glycol, 1,3-butanediol, and glycerin), esters of polyhydric alcohols (such as glycerol monoacetate, diacetate, or triacetate), and aliphatic esters of monocarboxylic acids, dicarboxylic acids, or polycarboxylic acids (such as dimethyl dodecanediate and dimethyl tetradecanediate). Preferred aerosol-forming compounds are polyhydric alcohols (such as propylene glycol, triethylene glycol, 1,3-butanediol, and most preferably glycerin) or mixtures thereof. The aerosol-forming substrate may have an aerosol-forming material content of more than 5 percent by dry weight. The aerosol-forming substrate may have an aerosol-forming material content of approximately 5 percent to approximately 30 percent by dry weight. The aerosol-forming substrate may have an aerosol-forming material content of approximately 20 percent by dry weight.

[0090] The aerosol-forming substrate may contain homogenized tobacco material, an aerosol-forming agent, and water.

[0091] The homogenized tobacco material may be supplied in one of the following forms: folded, crumpled, or cut into strips. The sheet may be cut into strips having a width of about 0.2 mm to about 2 mm, more preferably about 0.4 mm to about 1.2 mm. The width of the strips may be about 0.9 mm.

[0092] The aerosol-forming substrate may include an internal cavity. In other words, the aerosol-forming substrate may be tubular. The aerosol-forming substrate may include an internal surface having an internal diameter, which demarcates an internal cavity extending in the longitudinal direction within the aerosol-forming substrate. By providing an internal cavity within the aerosol-forming substrate, it may be possible to insert a heating element into the aerosol-forming substrate within the cavity without penetrating the substrate or altering the substrate's structure. Providing an internal cavity may also be beneficial in further reducing the thickness of the aerosol-forming substrate and enhancing the heat transfer advantages described above.

[0093] If the aerosol-forming substrate includes an internal surface that demarcates an inner cavity, the internal surface may have the same cross-sectional shape as the external surface. In particular, the internal surface may have a substantially circular, elliptical, or stadium-shaped cross-section.

[0094] The aerosol-generating article may comprise a layer of thermally conductive material. The layer of thermally conductive material may cover at least a portion of the otherwise exposed aerosol-forming substrate. The layer of thermally conductive material may be located at least on the outer surface of the substrate. The layer of thermally conductive material may be located at least on the inner surface of the substrate. The layer of thermally conductive material may be located at least on the inner and outer surfaces of the substrate. By providing a layer of thermally conductive material on the otherwise exposed substrate surface, heat from a heating element received by or engaged with the substrate can be distributed over a wider area of ​​the aerosol-forming substrate, potentially improving the heat transfer efficiency between the heating element and the aerosol-forming substrate. The layer of thermally conductive material may also create physical separation between the heating element received in the inner cavity and the aerosol-forming substrate, which can reduce the risk of overheating the aerosol-forming substrate in areas of the substrate near the heating element. The layer of thermally conductive material may also increase the robustness of the tubular aerosol-forming substrate, which may be reduced by the reduction in substrate thickness due to the provision of an inner cavity.

[0095] As used herein, the term “thermally conductive” refers to a material having a thermal conductivity of at least 10 W / mK, preferably at least 40 W / mK, and more preferably at least 100 W / mK at 23 degrees Celsius and 50% relative humidity. Preferably, the layer of thermally conductive material may include a material having a thermal conductivity of at least 40 W / mK, preferably at least 100 W / mK, more preferably at least 150 W / mK, and even more preferably at least 200 W / mK at 23 degrees Celsius and 50% relative humidity.

[0096] Examples of suitable conductive materials include, but are not limited to, aluminum, copper, zinc, nickel, silver, and combinations thereof.

[0097] The aerosol-forming substrate may have a rod comprising a plurality of elongated tubular elements. The elongated tubular elements may contain tobacco material. The plurality of elongated tubular elements contained in the aerosol-forming substrate must not be confused with tubular elements positioned downstream of the aerosol-forming substrate.

[0098] By adjusting the number, equivalent diameter, and thickness of the elongated tubular elements of the rod, it may be advantageously possible to adjust the density and porosity of the rod. Generally, an aerosol-forming substrate comprising multiple elongated tubular elements of homogenized tobacco may advantageously exhibit a more uniform density than an aerosol-forming substrate containing fragments of tobacco material. The geometric shape of the elongated tubular elements may be such that a particularly stable channel is provided for airflow along the rod. This may advantageously allow for consistent fine-tuning of the RTD, enabling the consistent and highly accurate production of aerosol-forming substrates with a given RTD.

[0099] The weight of an aerosol-forming substrate containing homogenized tobacco elongated tubular elements can be determined by the number, size, density, and spacing of the tubular elements. This reduces weight discrepancies between aerosol-forming substrates of the same dimensions and can result in a lower rejection rate of aerosol-forming substrates whose weight falls outside the selected tolerance range compared to aerosol-forming substrates containing tobacco material fragments.

[0100] A variation in the thickness of the elongated tubular elements within the rod can also be advantageously used to adjust the homogenized tobacco content within the rod. For example, in elongated tubular elements formed from rolled fragments of homogenized tobacco web, the thickness of the elongated tubular elements can be adjusted by changing the number of times the fragments are rolled around the longitudinal axis, or by changing the thickness of the homogenized tobacco web itself. This can increase design flexibility compared to aerosol-generating articles containing fragments of tobacco material.

[0101] The size, geometric shape, and arrangement of the elongated tubular elements within the rod can be easily adapted to facilitate the insertion of a heating element into the rod of the aerosol-generating article. Since the tubular elements are substantially linear within the rod and extend along their long axis, the insertion of an internal heating element (such as a heater blade) extending along its long axis can be facilitated. A regular arrangement of the elongated tubular elements within the rod can also advantageously optimize heat transfer from the heating element through the rod.

[0102] Inserting (and removing from) an aerosol generator heater into an aerosol-forming substrate containing fragments of tobacco material may cause the tobacco material fragments to detach from the aerosol-forming substrate. This may necessitate more frequent cleaning of the heater element and other parts of the aerosol generator to remove the detached fragments. In contrast, inserting and removing an aerosol generator heater into an aerosol-forming substrate comprising multiple elongated tubular elements of homogenized tobacco material is advantageous in that the tendency for material detachment can be significantly reduced.

[0103] A rod containing multiple elongated tubular elements can be manufactured in a continuous process that can be carried out quickly and efficiently, and can be conveniently integrated into existing production lines for the manufacture of aerosol-generating articles.

[0104] It is preferable that the rod of the aerosol-forming substrate has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating article.

[0105] The rod of the aerosol-forming substrate may have an outer diameter of at least 5 mm. The rod of the aerosol-forming substrate may have an outer diameter of about 5 mm to about 12 mm, for example, about 5 mm to about 10 mm, or about 6 mm to about 8 mm. Preferably, the rod of the aerosol-forming substrate may have an outer diameter of 7.2 mm ± 10 percent.

[0106] The rod of the aerosol-forming substrate may have a length of about 5 mm to about 100 mm. Preferably, the rod of the aerosol-generating substrate may have a length of at least about 5 mm, more preferably at least about 7 mm. Preferably, the rod of the aerosol-generating substrate may have a length of less than about 80 mm, more preferably less than about 65 mm, and even more preferably less than about 50 mm. Preferably, the rod of the aerosol-generating substrate may have a length of less than about 35 mm, more preferably less than 25 mm, and even more preferably less than about 20 mm. The rod of the aerosol-forming substrate may have a length of about 10 mm, and the rod of the aerosol-forming substrate may have a length of about 12 mm.

[0107] The rod of the aerosol-forming substrate may have a substantially uniform cross-section along its length. It may be preferable that the rod of the aerosol-forming substrate has a substantially circular cross-section.

[0108] A rod comprising elongated tubular elements may be enclosed by a wrapper. The elongated tubular elements may be assembled such that they extend along their long axis.

[0109] The multiple elongated tubular elements of the rod of the aerosol generating article according to the present invention may be formed of a homogeneous tobacco material, which may include particulate tobacco obtained by grinding. All of the multiple elongated tubular elements may have substantially the same composition as one another. Similarly, the multiple elongated tubular elements may include tubular elements of at least two different compositions.

[0110] At least one elongated tubular element in the rod may include a rolled strip cut from a sheet or web of homogenized tobacco material.

[0111] A sheet or web of homogenized tobacco material may have a tobacco content of at least about 40 weight percent, more preferably at least about 60 weight percent, more preferably at least about 70 weight percent, and most preferably at least about 90 weight percent, on a dry weight basis.

[0112] A sheet or web of homogenized tobacco material used in an aerosol-forming substrate may contain one or more endogenous binders (i.e., endogenous tobacco binders), one or more exogenous binders (i.e., exogenous tobacco binders), or a combination thereof, to assist in agglomerating particulate tobacco. A sheet of homogenized tobacco material used in an aerosol-forming substrate may also contain other additives, including but not limited to tobacco fibers and non-tobacco fibers, aerosol-forming agents, wetting agents, plasticizers, flavoring agents, fillers, aqueous and non-aqueous solvents, and combinations thereof.

[0113] Suitable exogenous binders to be included in sheets or webs of homogenized tobacco material used in aerosol-forming substrates are known in the art and include, but are not limited to, gums (e.g., guar gum, xanthan gum, gum arabic, locust bean gum), cellulosic binders (e.g., hydroxypropylcellulose, carboxymethylcellulose, hydroxyethylcellulose, methylcellulose, and ethylcellulose), polysaccharides (e.g., starch, organic acids (e.g., alginic acid), conjugated base salts of organic acids (e.g., sodium alginate), agar, pectin), and combinations thereof.

[0114] Suitable non-tobacco fibers to be included in sheets or webs of homogenized tobacco material used in aerosol-forming substrates are known in the art and include, but are not limited to, cellulose fibers, coniferous fibers, hardwood fibers, jute fibers, and combinations thereof. Before being included in sheets of homogenized tobacco material used in aerosol-forming substrates, the non-tobacco fibers may be treated by suitable processes known in the art, including, but are not limited to, mechanical pulping, purification, chemical pulping, bleaching, sulfate pulping, and combinations thereof.

[0115] The homogenized tobacco material sheet or web may contain an aerosol-forming agent.

[0116] The homogenized tobacco sheets or webs used in the aerosol-generating articles of the present invention may be prepared by methods known in the art (for example, the method disclosed in International Patent Publication No. A-2012 / 164009 A2). The sheets of homogenized tobacco material used in the aerosol-generating articles may be formed by a casting process from a slurry containing particulate tobacco, guar gum, cellulose fibers, and glycerin.

[0117] Alternatively, the elongated tubular elements of the homogenized tobacco material used in the aerosol-forming substrate according to the present invention may be formed by extrusion. For example, a slurry containing particulate tobacco obtained by crushing or otherwise subdividing tobacco leaf laminae may be pressed through a die of a desired cross-section. Furthermore, additive manufacturing may also be used to produce tubular elements of the homogenized tobacco material.

[0118] The elongated tubular element may have an equivalent diameter of approximately 0.03 mm to approximately 3 mm. Preferably, the elongated tubular element may have an equivalent diameter of at least approximately 0.1 mm. More preferably, the elongated tubular element may have an equivalent diameter of at least approximately 0.3 mm.

[0119] Similarly, it is preferable that the elongated tubular elements have an equivalent diameter of less than approximately 2 millimeters. More preferably, the elongated tubular elements have an equivalent diameter of less than approximately 1 millimeter.

[0120] The elongated tubular element may have an equivalent diameter of approximately 0.7 mm to approximately 2.7 mm, or it may have an equivalent diameter of approximately 0.3 mm to approximately 1.1 mm.

[0121] When elongated tubular elements are formed by rolling up fragments of homogenized tobacco material, the fragments may have a width of at least about 1 millimeter. Preferably, the fragments of homogenized tobacco material may have a width of at least about 2 millimeters. More preferably, the fragments of homogenized material may have a width of at least about 3 millimeters.

[0122] The homogenized tobacco material fragments may have a width of approximately 1 mm to approximately 3.5 mm, or they may have a width of approximately 2.4 mm to approximately 8.2 mm.

[0123] The homogenized tobacco material fragments may be cut from a sheet or web having a thickness of at least about 40 microns, more preferably at least about 60 microns, more preferably at least about 80 microns, and most preferably at least about 100 microns. Similarly, the homogenized tobacco material fragments may be cut from a sheet or web having a thickness of about 5000 microns or less, more preferably about 2000 microns or less, more preferably about 1000 microns or less, and most preferably about 500 microns or less. For example, the thickness of the sheet or web may be about 40 microns to about 5000 microns, more preferably about 60 microns to about 2000 microns, more preferably about 80 microns to about 1000 microns, and most preferably about 100 microns to about 500 microns.

[0124] The thickness of the elongated tubular element may be at least about 40 microns, more preferably at least about 80 microns, more preferably at least about 120 microns, and most preferably at least about 160 microns. Similarly, the thickness of the elongated tubular element may be less than about 5000 microns, more preferably less than about 2500 microns, and most preferably less than about 1000 microns.

[0125] Elongated tubular elements can be formed from porous tobacco material so that air can flow through the walls of the tubular elements, i.e., so that substantially radial airflow within the rod is not obstructed. If elongated tubular elements are formed by rolling up homogenized tobacco strips, the strips themselves can be formed from porous tobacco material.

[0126] As used herein in relation to homogenized tobacco materials, the term “porous” may indicate that the tobacco material was produced within an inherent porosity range such that sufficient pores or gaps are provided within the structure of the sheet or web to allow airflow through the sheet or web in a direction transverse to the surface of the sheet or web. Similarly, the term “porous” may indicate that each sheet or web of tobacco material has multiple airflow holes to provide a desired porosity. For example, a sheet of tobacco material may be perforated with an airflow hole pattern before the winding operation is carried out to produce elongated tubular elements of a rod of aerosol-forming substrate. The airflow holes may be perforated randomly or uniformly across the sheet. The airflow hole pattern may cover substantially the entire surface of the sheet, or it may cover one or more specific areas of the sheet, with the remaining areas having no airflow holes.

[0127] Fractions of homogenized tobacco material that can form elongated tubular elements may be textured. For example, the sheet or web from which the fragments are cut may have multiple spaced indentations, protrusions, perforations, or a combination thereof. The texture may be provided on one side of each sheet or on both sides of each sheet.

[0128] Including one or more elongated tubular elements formed from crimped strips can help provide and maintain some spacing between adjacent tubular elements within the rod.

[0129] The additive may be applied to at least a portion of the surface of at least one of the multiple tubular elements. The additive may be a solid additive, a liquid additive, or a combination of a solid additive and a liquid additive. Suitable solid and liquid additives for use in the present invention are known in the art and include, but are not limited to, flavoring agents (e.g., menthol), adsorbents (e.g., activated carbon), fillers (e.g., calcium carbonate), and plant-based additives.

[0130] To form a substantially elongated tubular element, the homogenized tobacco material strips may be wound around the longitudinal axis for at least about 345 degrees. Preferably, the homogenized tobacco material strips may be wound around the longitudinal axis for at least about 360 degrees. More preferably, the homogenized tobacco material strips may be wound around the longitudinal axis for at least about 540 degrees. Similarly, the homogenized tobacco material strips may preferably be wound around the longitudinal axis for less than about 1800 degrees. More preferably, the homogenized tobacco material strips may be wound around the longitudinal axis for less than about 900 degrees. Preferably, the homogenized tobacco material strips may be wound around the longitudinal axis for about 345 to about 540 degrees.

[0131] Each elongated tubular element may have a length substantially equal to the length of the rod of the aerosol-forming substrate. Each elongated tubular element may have a length of about 10 millimeters, or each elongated tubular element may have a length of about 12 millimeters.

[0132] The rod of the aerosol-forming substrate may comprise fewer than 200 elongated tubular elements of homogenized tobacco material. More preferably, the rod of the aerosol-forming substrate may comprise fewer than 150 elongated tubular elements. Even more preferably, the rod of the aerosol-forming substrate may comprise fewer than 100 elongated tubular elements.

[0133] Similarly, a rod of aerosol-forming substrate may comprise at least about 15 elongated tubular elements of homogenized tobacco material. More preferably, a rod of aerosol-forming substrate may comprise at least about 30 elongated tubular elements. Even more preferably, a rod of aerosol-forming substrate may comprise at least about 40 elongated tubular elements. A rod of aerosol-forming substrate may contain about 15 to about 100 strands of non-tobacco material.

[0134] In a rod of aerosol-forming substrate, the elongated tubular elements may be aligned substantially parallel to one another.

[0135] The elongated tubular elements of the homogenized tobacco material may have a substantially oval cross-section, a substantially elliptical cross-section, or a substantially circular cross-section. As described above, the elongated tubular elements used in aerosol-generating articles can be effectively formed by winding a strip of the homogenized tobacco material around its longitudinal axis in a manner slightly less than 360 degrees. This results in an element with an effectively C-shaped cross-section, with the slit extending along the longitudinal axis for the entire length of the elongated tubular element.

[0136] Aerosol generating systems are also provided. An aerosol generating system may comprise any of the aerosol generating articles disclosed above and an aerosol generating device. The aerosol generating device may comprise a heating element or part of a heating element for heating the aerosol generating article.

[0137] As used herein, the term "aerosol generating system" refers to a combination of an aerosol generating device and an aerosol generating article.

[0138] Since the aerosol generating system of this disclosure includes the aerosol generating article as disclosed above, the advantages described above for the aerosol generating article also apply to the system itself.

[0139] The heating element may be any suitable type of heating element. The heating element may be an internal heating element. The heating element may be an elongated heating element. The elongated heating element may be blade-shaped. The elongated heating element may be pin-shaped. The elongated heating element may have a tapered shape, or at least a tapered end. The elongated heating element may have a pointed end. The heating element may be conical. The elongated heating element may have any suitable shape that is arranged to facilitate insertion of the heating element into the aerosol-forming substrate. Advantageously, the elongated heating element may provide easier engagement or disengagement of the heating element between the aerosol-generating article and the device, or both easier engagement and disengagement.

[0140] The heating element may be an external heating element. As used herein, the term “external heating element” refers to a heating element configured to heat the outer surface of the aerosol-forming substrate. The external heating element may at least partially surround a cavity for receiving the aerosol-forming substrate.

[0141] The heating element may include at least one resistance heating element.

[0142] At least one resistive heating element may include an electrically insulated substrate and one or more conductive tracks on the electrically insulated substrate.

[0143] An electrically insulated substrate can be stable at the operating temperature of at least one heating element. An electrically insulated substrate can be stable at temperatures up to about 400 degrees Celsius, more preferably about 500 degrees Celsius, more preferably about 600 degrees Celsius, more preferably about 700 degrees Celsius, and most preferably about 800 degrees Celsius.

[0144] The operating temperature of at least one resistive heating element in use may be at least approximately 200 degrees Celsius. The operating temperature of at least one resistive heating element in use may be less than approximately 700 degrees Celsius. The operating temperature of at least one resistive heating element in use may be less than approximately 600 degrees Celsius. The operating temperature of at least one resistive heating element in use may be less than approximately 500 degrees Celsius. The operating temperature of at least one resistive heating element in use may be less than approximately 400 degrees Celsius.

[0145] The electrically insulated substrate may include any suitable material. For example, the electrically insulated substrate may include one or more of paper, glass, ceramic, anodized metal, coated metal, and polyimide. The ceramic may be mica, alumina (Al2O3), or zircona (ZrO3). 2) This may include the following. The electrically insulated substrate may have a thermal conductivity of about 40 watts / meter Kelvin or less, preferably about 20 watts / meter Kelvin or less, and ideally about 2 watts / meter Kelvin or less.

[0146] Suitable materials for forming resistive heating elements, and in particular one or more conductive tracks, include, but are not limited to, semiconductors such as doped ceramics, "conductive" ceramics (e.g., molybdenum disilide), carbon, graphite, metals, metal alloys, and composite materials made of ceramic and metal materials. Such composite materials may include doped or undoped ceramics. A suitable example of a doped ceramic is doped silicon carbide. Suitable examples of metals include titanium, zirconium, tantalum, and platinum group metals. Suitable examples of metal alloys include stainless steel, nickel-containing, cobalt-containing, chromium-containing, aluminum-containing, titanium-containing, zirconium-containing, hafnium-containing, niobium-containing, molybdenum-containing, tantalum-containing, tungsten-containing, tin-containing, gallium-containing, manganese-containing, and iron-containing alloys, as well as nickel, iron, cobalt, stainless steel-based superalloys, Timetal®, and iron-manganese-aluminum alloys.

[0147] The resistive heating element may include one or more stamped portions of an electrically resistant material (such as stainless steel). At least one resistive heating element may include a heating wire or filament (e.g., Ni-Cr (nickel-chromium), platinum, tungsten, or alloy wire).

[0148] The heating element may include at least one induction heating arrangement.

[0149] At least one induction heating arrangement may include at least one inductor coil. The inductor coil is arranged to generate a fluctuating magnetic field when it receives a fluctuating current from a power source. Such fluctuating current may be in the range of about 5 kilohertz to about 500 kilohertz. The fluctuating current may be a high-frequency fluctuating current. As used herein, the term “high-frequency fluctuating current” means a fluctuating current having a frequency of about 500 kilohertz to about 30 megahertz. A high-frequency fluctuating current may have a frequency of about 1 megahertz to about 30 megahertz (e.g., about 1 megahertz to about 10 megahertz, or about 5 megahertz to about 8 megahertz). The fluctuating current may be an alternating current that generates an alternating magnetic field.

[0150] An inductor coil can have any preferred form. For example, an inductor coil may be a flat inductor coil. A flat inductor coil may be wound helically in a substantially planar plane. Preferably, an inductor coil may be a tubular inductor coil. Typically, a tubular inductor coil may be wound helically around a major axis. An inductor coil may be elongated. Particularly preferably, an inductor coil may be an elongated tubular inductor coil. An inductor coil may have any preferred cross-section. An inductor coil may have a circular, elliptical, square, rectangular, triangular, or other polygonal cross-section.

[0151] The inductor coil can be formed from any suitable material. The inductor coil can be formed from a conductive material. Preferably, the inductor coil can be formed from a metal or a metal alloy.

[0152] As used herein, "conductive" means 1 × 10⁻¹⁰ at 20 degrees Celsius. -4 This refers to materials having an electrical resistivity of ohms (Ω·m) or less.

[0153] At least one induction heating arrangement may include at least one susceptor. As discussed above, the susceptor may also be included in the aerosol generating article.

[0154] The susceptor may be positioned such that when an aerosol-generating article is received by the aerosol generator, the oscillating electromagnetic field generated by the inductor coil induces a current within the susceptor, thereby heating the susceptor. The aerosol generator is preferably capable of generating a fluctuating electromagnetic field having a magnetic field strength (H-field strength) of 1 to 5 kiloamperes / meter (kA / m), preferably 2 to 3 kA / m, for example about 2.5 kA / m. The aerosol generator is preferably capable of generating a fluctuating electromagnetic field having a frequency of 1 to 30 MHz, for example 1 to 10 MHz, for example 5 to 7 MHz.

[0155] The susceptor may contain any suitable material. The susceptor may be formed from any material that can be inductively heated to a temperature sufficient to release volatile compounds from the aerosol-forming substrate or flavor substrate. Preferred susceptors may be heated to temperatures above approximately 250 degrees Celsius. Preferred susceptors may be formed from conductive materials. Suitable materials for the susceptor include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel, nickel-containing compounds, titanium, and composite materials of metallic materials. Preferred susceptors may contain metal or carbon. Some preferred susceptors may contain ferromagnetic materials such as ferrite iron, ferromagnetic alloys such as ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrite. Some preferred susceptors may consist of ferromagnetic materials. Preferred susceptors may contain aluminum. Preferred susceptors may consist of aluminum. The susceptor may contain at least about 5 percent, at least about 20 percent, at least about 50 percent, or at least about 90 percent of ferromagnetic or paramagnetic material.

[0156] The susceptor may be formed from a material that is substantially impermeable to gas. In other words, it is preferable that the susceptor be formed from a material that is not permeable to gas.

[0157] The susceptor may have any suitable shape. For example, the susceptor may be elongated. The susceptor may have any suitable cross-section. For example, the susceptor may have a circular, elliptical, square, rectangular, triangular, or other polygonal cross-section. The susceptor may also be tubular.

[0158] The susceptor may include a susceptor layer provided on a support. When the susceptor is placed in a fluctuating magnetic field, eddy currents are induced near the susceptor surface, resulting in an effect called the skin effect. Therefore, the susceptor can be formed from a relatively thin layer of susceptor material while ensuring that the susceptor is effectively heated in the presence of a fluctuating magnetic field. Fabricating the susceptor from a support and a relatively thin susceptor layer can facilitate the production of simple, inexpensive, and robust aerosol-generating articles.

[0159] The support may be formed from a material that is not susceptible to induction heating. Advantageously, this can reduce heating of the susceptor surface that is not in contact with the aerosol-forming substrate, where the surface of the support forms the surface of the susceptor that is not in contact with the aerosol-forming substrate.

[0160] The support may include an electrically insulating material. As used herein, “electrically insulating” means at least 1 × 10⁻¹⁰ degrees Celsius. 4 This refers to a material that has an electrical resistivity in ohms (Ωm).

[0161] Forming a support from an insulating material can provide an insulating barrier between the susceptor layer and other components of the induction heating arrangement, such as the inductor coil surrounding the induction heating element. Advantageously, this can reduce heat transfer between the susceptor and other components of the induction heating system.

[0162] The thermal insulation material may also have a bulk thermal diffusivity of about 0.01 square centimeters per second (cm² / s) or less, as measured using the laser flash method. Providing a support with such thermal diffusivity can result in a support with high thermal inertia, which can reduce heat transfer between the susceptor layer and the support and reduce temperature fluctuations of the support.

[0163] The susceptor may have a protective outer layer, such as a protective ceramic layer or a protective glass layer. The protective outer layer may improve the durability of the susceptor and facilitate cleaning of the susceptor. The protective outer layer may substantially surround the susceptor. The susceptor may include a protective coating formed from glass, ceramic, or an inert metal.

[0164] If the susceptor is included in the aerosol generator, the susceptor may be located within the device cavity. The susceptor may extend into the device cavity in the direction of the long axis of the device cavity. The susceptor may be elongated. An elongated susceptor may be blade-shaped. An elongated susceptor may be pin-shaped. An elongated susceptor may have a tapered shape, or at least a tapered end. An elongated susceptor may have a pointed end. An elongated element may be conical.

[0165] If the susceptor is included in the aerosol generator, the susceptor may be an internal heating element configured to be at least partially inserted into the aerosol-forming substrate of the aerosol-generating article when the aerosol-generating article is received into the device cavity. If the aerosol-forming substrate includes an inner cavity, the susceptor may be configured to be at least partially inserted into the inner cavity of the aerosol-forming substrate when the aerosol-generating article is received into the device cavity.

[0166] The aerosol generator may be equipped with a power source. The power source may be a DC voltage source. The power source may be a battery. For example, the power source may be a nickel-metal hydride battery, a nickel-cadmium battery, or a lithium-based battery (e.g., a lithium-cobalt battery, a lithium iron phosphate battery, or a lithium polymer battery). The power source may be another form of charge storage device, such as a capacitor. The power source may require recharging and may have a capacity to store enough energy to operate the aerosol generator.

[0167] A power supply may be electrically connected to the heater to power heating elements such as a substrate heating element and a downstream heating element. When a heating element receives power from the power supply, it can generate heat. The power supply may be configured to supply enough power to the heating elements to heat the aerosol-forming substrate to a temperature at which volatile compounds are released from the aerosol-forming substrate.

[0168] The aerosol generator may include a housing. The housing may define, at least partially, a cavity for receiving an aerosol generating article.

[0169] The aerosol generator may include an air intake port of at least one device that is in fluid communication with the cavity. When the aerosol generator includes a housing, the housing may at least partially define the air intake port of at least one device. It may be desirable that the air intake port of the device allow ambient air to be drawn into the upstream end of the aerosol-forming substrate.

[0170] The aerosol generator may include a controller. The controller may be configured to control the power supply from the power source to the heating element. The controller may be any suitable controller. The controller may include any suitable electrical circuits and electrical components. The controller may include a processor and memory. The controller may include a microprocessor, which may be a programmable microprocessor.

[0171] The aerosol generator may include a sensor for detecting the airflow indicating that the user is inhaling smoke. The airflow sensor may be an electromechanical device. The airflow sensor may be a mechanical device, an optical device, an opticmechanical device, or a micro-electromechanical system (MEMS) based sensor. The aerosol generator may include a manually operable switch for the user to initiate smoke inhalation.

[0172] The aerosol generator may include an indicator to show when at least one heat source is activated. The indicator may include a light that is activated when at least one heat source is activated.

[0173] The aerosol generator may have at least one electrical connector. At least one electrical connector may be configured to charge a power supply. At least one electrical connector may be configured to connect to another electrical device. At least one electrical connector may have an external plug or socket with at least one external electrical contact that allows the aerosol generator to be connected to another electrical device. For example, the aerosol generator may have a USB plug or USB socket that allows the aerosol generator to be connected to another USB-enabled device. For example, the USB plug or socket may allow the aerosol generator to be connected to a USB charger in order to charge the rechargeable power supply within the aerosol generator. The USB plug or socket may support data transfer to or from the aerosol generator, or both. Similarly, the aerosol generator may be connected to a computer to transfer data to the device, such as a new heating profile for a new aerosol generating article.

[0174] When the aerosol generator includes a USB plug or socket, the aerosol generator may further include a removable cover that covers the USB plug or socket when not in use. When the USB plug or socket is a USB plug, the USB plug may be selectively retractable within the device.

[0175] These and other features and advantages of the present invention will become more apparent in light of the following detailed description of preferred embodiments, which are given only by illustrative and non-limiting examples with reference to the accompanying figures. [Brief explanation of the drawing]

[0176] [Figure 1] Figure 1 shows a cross-sectional view along the long axis of an aerosol generating article, which includes an embedded susceptor and wrapper. [Figure 2a] Figure 2a shows a cross-section of the aerosol-generating article shown in Figure 1. [Figure 2b] Figure 2b shows a cross-section of the overlapping region defined by the wrapper of the aerosol-generating article circled in Figure 2a. [Figure 3] Figure 3 shows a cross-sectional view along the long axis of an aerosol generating article equipped with a tubular element and a filter. [Figure 4] Figure 4 shows a cross-sectional view along the long axis of an aerosol generating article equipped with an upstream element and an aerosol cooling element. [Figure 5] Figure 5 shows a cross-sectional view along the long axis of an aerosol generating system comprising an aerosol generator and one of the aerosol generating articles shown in Figures 1 to 4. [Figure 6] Figure 6 shows an external view of the aerosol generation system shown in Figure 5. [Modes for carrying out the invention]

[0177] The present invention is defined in the claims. However, a non-exclusive list of non-limiting embodiments is provided below. Any one or more features of these embodiments may be combined with any one or more features of other embodiments, embodiments, or disclosures described herein.

[0178] Example 1 Aerosol-generating article, Aerosol-forming substrate and, A wrapper surrounding an aerosol-forming substrate, The wrapper defines an overlapping region in which the wrapper overlaps itself, and the overlapping region includes a first section and a second section positioned externally on the first section. The second section includes a crease or fold that defines the folded section at one end of the wrapper, An aerosol-generating article in which a folded section is sandwiched between a first section and a second section. Example 2 An aerosol-generating article according to claim embodiment 1, wherein an inner adhesive is placed between the folded section and the first section. Example 3 An aerosol-generating article according to either Example 1 or 2, wherein the outer adhesive is placed between the folded section and the second section. Example 4 An aerosol-generating article according to either of Examples 2 and 3, wherein the adhesive comprises one or more of the following: gum arabic, natural or synthetic resin, starch, and varnish. Example 5 An aerosol generating article according to any one of Examples 1 to 4, further comprising a heating element embedded in an aerosol-forming substrate. Example 6 An aerosol generating article according to Example 5, wherein the heating element is a susceptor. Example 7 An aerosol generating article according to either Example 5 or 6, wherein the heating element is completely surrounded by an aerosol-forming substrate and extends along the entire length of the aerosol-forming substrate. Example 8 An aerosol generating article according to any one of Examples 1 to 7, wherein the diameter of the aerosol generating article is approximately 3 mm to approximately 8 mm. Example 9 An aerosol-generating article according to any one of Examples 1 to 8, wherein the wrapper has a thickness of about 60 micrometers to about 200 micrometers, preferably about 78 micrometers to about 160 micrometers, more preferably 78 micrometers to about 140 micrometers, more preferably about 100 micrometers to about 140 micrometers, and most preferably about 125 micrometers to about 140 micrometers. Example 10 An aerosol-generating article according to any one of Examples 1 to 9, wherein the aerosol-forming substrate comprises one or more of tobacco, nicotine, a gel composition, and a flavor substrate. Example 11 An aerosol-generating article according to any one of Examples 1 to 10, wherein the wrapper has a basis weight of approximately 10 grams / m² to 28 grams / m², preferably approximately 10 grams / m² to 16 grams / m². Example 12 An aerosol-generating article according to any one of Examples 1 to 11, wherein the wrapper has a porosity of approximately 30 to approximately 80 cholesterol units, preferably approximately 30 to 50 cholesterol units, and most preferably 30 to 40 cholesterol units. Example 13 An aerosol-generating article according to any one of Examples 1 to 12, wherein the wrapper has a roughness of approximately 50 Becks to approximately 1000 Becks, more preferably approximately 100 Becks to approximately 200 Becks. Example 14 An aerosol generating article according to any one of Examples 1 to 13, further comprising a filter positioned downstream of the aerosol-forming substrate. Example 15 An aerosol generating article according to any one of Examples 1 to 14, further comprising a support element positioned downstream of the aerosol-forming substrate. Example 16 An aerosol generating article according to Example 15, wherein the support element includes a first hollow tubular segment. Example 17 An aerosol generating article according to either Example 15 or 16, wherein the support element is positioned in the longitudinal direction immediately downstream of the aerosol forming substrate. Example 18 An aerosol-generating article according to any one of Examples 15-17, dependent on Example 14, wherein the filter is positioned longitudinally immediately downstream of the support element. Example 19 An aerosol generating article according to any one of Examples 15 to 18, further comprising an aerosol cooling element positioned in the longitudinal direction downstream of the support element. Example 20 An aerosol generating article according to Example 19, wherein the aerosol cooling element includes a second hollow tubular segment. Example 21 An aerosol generating article according to either Example 19 or 20, as opposed to Example 14, wherein the aerosol cooling element is positioned between the support element and the filter. Example 22 An aerosol generating article according to any one of Examples 1 to 21, further comprising a mouthpiece positioned at the downstream end of the aerosol generating article. Example 23 An aerosol generating article according to any one of Examples 1 to 22, further comprising an upstream element positioned at the upstream end of the aerosol generating article. Example 24 An aerosol-generating article according to any one of Examples 1 to 23, wherein the aerosol-forming substrate contains a liquid component. Example 25 An aerosol-generating article according to any one of Examples 1 to 24, wherein the aerosol-forming substrate contains a solid component. Example 26 An aerosol-generating article according to any one of Examples 1 to 25, wherein the aerosol-forming substrate includes a plant-derived material, preferably a homogenized plant-derived material. Example 27 An aerosol-generating article according to any one of Examples 1 to 26, wherein the aerosol-forming substrate contains a non-tobacco material. Example 28 An aerosol-generating article according to any one of Examples 1 to 27, wherein the aerosol-forming substrate contains a solid, homogenized tobacco material. Example 29 An aerosol-generating article according to Example 29, wherein the aerosol-forming substrate comprises an aggregate of at least one sheet of solid, homogenized tobacco material. Example 30 An aerosol-generating article according to Example 29, wherein the aggregate of at least one sheet comprises a textured sheet, a crimped sheet, or both. Example 31 An aerosol-generating article according to any one of Examples 28 to 30, wherein a solid, homogenized tobacco material contains fine fragments of the tobacco material. Example 32 An aerosol-generating article according to any one of Examples 25 to 31, in which the aerosol-forming substrate has a rod containing a plurality of elongated tubular elements, as is dependent on Example 25. Example 33 An aerosol-generating article according to Example 32, which is dependent on Example 28, comprising multiple elongated tubular elements containing a solid, homogenized tobacco material. Example 34 An aerosol-generating article according to Example 33, wherein at least one elongated tubular material comprises a rolled fragment cut from a sheet or web of solid, homogenized tobacco material. Example 35 An aerosol generating article according to any one of Examples 1 to 34, wherein the aerosol-forming substrate is a hollow tubular substrate defining an inner cavity. Example 36 An aerosol-generating article according to any one of Examples 1 to 35, further comprising a layer of thermally conductive material. Example 37 An aerosol generating article according to any one of Examples 1 to 36, wherein the aerosol-forming substrate includes an aerosol-forming body. Example 38 An aerosol generator equipped with a heating element or a part thereof. Example 39 An aerosol generator according to Example 38, wherein the heating element includes at least one resistance heating element. Example 40 An aerosol generator according to Example 39, comprising at least one resistive heating element, an electrically insulated substrate, and one or more conductive tracks on the electrically insulated substrate. Example 41 An aerosol generator according to any one of Examples 38 to 40, wherein the heating element includes at least one induction heating arrangement, each induction heating arrangement including at least one inductor coil and optionally at least one susceptor. Example 42 An aerosol generator according to Example 41, wherein at least one inductor coil is arranged to generate a fluctuating magnetic field when it receives a fluctuating current from a power source, and the fluctuating current is approximately 5 kHz to approximately 500 kHz. Example 43 An aerosol generator according to Example 41, wherein at least one inductor coil is arranged to generate a fluctuating magnetic field when it receives a fluctuating current from a power source, and the fluctuating current is approximately 500 kilohertz to approximately 5 megahertz. Example 44 An aerosol generator according to any one of Examples 41 to 43, wherein at least one inductor coil is a flat inductor coil, such as a flat inductor coil wound helically in a substantially planar manner. Example 45 An aerosol generator according to any one of Examples 41 to 43, wherein at least one inductor coil is a tubular inductor coil, such as a tubular inductor coil wound helically around its long axis. Example 46 An aerosol generator according to any one of Examples 41 to 45, wherein at least one inductor coil is formed from a conductive material. Example 47 An aerosol generator according to any one of Examples 41 to 46, in which case at least one susceptor is formed from a conductive material, or in which the aerosol generator comprises at least one susceptor. Example 48 An aerosol generator according to any one of Examples 41 to 47, wherein at least one susceptor comprises a susceptor layer provided on a support, and the support preferably comprises a thermal insulating material, relating to Example 6, or the aerosol generator comprises at least one susceptor. Example 49 An aerosol generator according to any one of Examples 39 to 48, wherein the heating element includes at least one resistance heating element and at least one induction heating arrangement. Example 50 An aerosol generator according to any one of Examples 38 to 49, wherein the heating element includes an internal heating element. Example 51 An aerosol generator according to any one of Examples 38 to 50, wherein the heating element includes an external heating element. Example 52 An aerosol generator according to any one of Examples 38 to 51, further equipped with a power supply. Example 53 An aerosol generator according to Example 52, in which the power supply is electrically connected to the heating element. Example 54 An aerosol generating device according to any one of Examples 38 to 53, further comprising a cavity for receiving an aerosol generating article. Example 55 An aerosol generator according to any one of Examples 38 to 54, further comprising a device housing. Example 56 Aerosol generators according to Examples 54 and 55, wherein the device housing defines at least partially a cavity for receiving an aerosol-generating article. Example 57 An aerosol generator according to any one of Examples 38 to 56, further comprising at least one device air intake. Example 58 An aerosol generator according to Example 57, in which the device housing includes at least one device air intake, as is the case with Example 55. Example 59 An aerosol generating article according to any one of Examples 38 to 58, further comprising a controller. Example 60 An aerosol-generating article according to any one of Examples 38 to 59, further comprising a sensor configured to detect an airflow indicating that a user is inhaling smoke. Example 61 An aerosol-generating article according to any one of Examples 38 to 60, further comprising at least one electrical connector. Example 62 An aerosol-generating article according to Example 61, wherein at least one electrical connector includes an external plug or socket such as a USB plug or USB socket. Example 63 An aerosol generating system comprising an aerosol generating article according to any one of Examples 1 to 37 and an aerosol generating device according to any one of Examples 38 to 62.

[0179] Figure 1 shows a cross-sectional view of an aerosol generating article 10 having an upstream end 13 and a downstream end 14, with the longitudinal direction of the aerosol generating article 10 defined between the upstream end 13 and the downstream end 14. The article 10 comprises an aerosol forming substrate 11 and a wrapper 30 surrounding the aerosol forming substrate 11.

[0180] In the embodiment shown in Figure 1, the heating element 40 is embedded within the aerosol-forming substrate 11. The heating element 40 is a susceptor 40. The susceptor 40 extends along the entire length of the aerosol-forming substrate 11.

[0181] Figure 2a shows a cross-section of the aerosol-generating article 10 of Figure 1. This figure shows that the wrapper 30 defines an overlapping region 41 in which the wrapper 30 overlaps itself. The overlapping region 41 includes a first section 42 and a second section 43 positioned externally on top of the first section 42. The second section 43 includes a fold 44 (or crease) that defines a folded section 45 at one end of the wrapper 40. The folded section 45 is sandwiched between the first section 42 and the second section 43.

[0182] The inner adhesive 50 is placed between the folded section 45 and the first section 42. The outer adhesive 51 is placed between the folded section 45 and the second section 43.

[0183] To clarify, the overlapping region in Figure 2a is shown in more detail in Figure 2b.

[0184] Figure 3 shows an aerosol generating article comprising an aerosol-forming substrate 11 and a wrapper 30, similar to the aerosol generating articles of Figures 1 and 2. The aerosol generating article 10 further comprises a support element 12 located immediately downstream of the aerosol-forming substrate 11. The tubular element 12 extends along its longitudinal axis and defines an opening adapted to allow substrate aerosols to flow toward the downstream end 14. In other words, the support element 12 includes a hollow tubular segment. In the embodiment of Figure 3, the filter 17 is located along its longitudinal axis immediately downstream of the support element 12. The wrapper 30 is identical to the wrapper 30 of the aerosol generating article 10 in Figures 1 and 2. The susceptor 40 extends along the entire length of the aerosol-forming substrate 11.

[0185] Figure 4 shows an aerosol generating article 10 equipped with the wrapper 30 shown in Figures 1, 2, and 3. The aerosol generating article 10 in Figure 4 will be described below insofar as it differs from the aerosol generating articles 10 in Figures 1, 2, and 3.

[0186] The aerosol generating article 10 in Figure 4 includes a support element 12 located immediately downstream of the aerosol forming substrate 11. In the embodiment of Figure 4, the upstream end of the support element 12 abuts against the downstream end of the aerosol forming substrate 11. In addition, the aerosol generating article 10 includes an aerosol cooling element 15 located immediately downstream of the support element 22. In the embodiment of Figure 4, the upstream end of the aerosol cooling element 15 abuts against the downstream end of the support element 12.

[0187] The support element 12 includes a first hollow tubular segment. The aerosol cooling element 15 includes a second hollow tubular segment. The hollow tubular segment is provided in the form of a hollow cylindrical tube made of cellulose acetate. Other configurations in which the support element, aerosol cooling element, or both do not include a hollow tubular segment are also compatible with the embodiment shown in Figure 4.

[0188] In Figure 4, the support element 12 and the aerosol cooling element 15 together define an intermediate hollow section of the aerosol generating article 10. Overall, the intermediate hollow section is adapted so that the substrate aerosol flows toward the downstream end 14 and does not substantially contribute to the overall draw resistance of the aerosol generating article 10.

[0189] In the embodiment shown in Figure 4, the filter 17 is positioned in the longitudinal direction immediately downstream of the aerosol cooling element 15. As shown in Figure 4, the upstream end of the filter 17 abuts against the downstream end of the aerosol cooling element 15.

[0190] The filter 17 is provided in the form of a cylindrical plug made of low-density cellulose acetate.

[0191] In Figure 4, the aerosol generating article 10 includes an upstream element 16. The upstream element 16 abuts against the upstream end of the aerosol forming substrate 11. This advantageously prevents the susceptor 40 from detaching. Furthermore, this ensures that consumers do not accidentally come into contact with the heated susceptor 40 after use.

[0192] The upstream element 16 is provided in the form of a cylindrical plug made of cellulose acetate.

[0193] In some not-shown embodiments of the embodiments shown in Figures 3 and 4, the aerosol generating article 10 includes a mouthpiece positioned immediately downstream of the filter 17.

[0194] Figure 5 shows a schematic longitudinal cross-section of an aerosol generating system comprising an aerosol generator 200 and an aerosol generating article 10. The aerosol generating article 10 may be any of the articles shown in Figures 1 to 4.

[0195] The aerosol generator 200 comprises a substantially cylindrical device housing 207 having a shape and size similar to that of a conventional cigar.

[0196] The aerosol generator 200 further comprises a power supply 201 in the form of a rechargeable nickel-cadmium battery, a controller 202 in the form of a printed circuit board including a microprocessor, an electrical connector 203, and a heating element 204. The heating element 204 is configured to heat the aerosol-forming substrate 11.

[0197] In the embodiment shown in Figure 5, the heating element 204 is an induction heating arrangement 204 that includes at least one inductor coil 206 intended to work in cooperation with the susceptor 40 of the aerosol generating article 10. However, other forms of heating elements, such as resistance heating elements, may be used. Similarly, the induction heating arrangement 204 may include a susceptor. The latter arrangement is preferably used with an aerosol generating article that does not include a susceptor.

[0198] The power supply 201, controller 202, and inductor coil 206 are all housed within the device housing 207. The inductor coil 206 of the aerosol generator 200 is located at the proximal end of the device 200. The electrical connector 203 is located at the distal end of the device housing 207.

[0199] As used herein, the term “proximal” refers to the user end or mouth end of an aerosol generator or aerosol generating article. The proximal end of a component of an aerosol generator or aerosol generating article is the end of the component closest to the user end, or the mouth end of the aerosol generator or aerosol generating article. As used herein, the term “distal” refers to the end opposite to the proximal end.

[0200] The controller 202 is configured to control the power supply from the power supply 201 to the inductor coil 206. The control device 202 further includes a DC / AC inverter including a Class D power amplifier. The controller 202 is also configured to control the recharging of the power supply 201 from the electrical connector 203. The controller 202 further includes a fume extraction sensor (not shown) configured to detect when the user has withdrawn an aerosol-generating article received in the device cavity 208.

[0201] The inductor coil 206 is connected to the controller 202 and the power supply 201, and the controller 202 is configured to supply a fluctuating current to the base inductor coil 206. When the fluctuating current is supplied to the inductor coil 206, the inductor coil 206 generates a fluctuating magnetic field, which inductively heats the susceptor 40.

[0202] As shown in Figure 6, the apparatus housing 207 also defines an apparatus air intake 213 adjacent to the distal end of the cavity 208 for receiving the aerosol generating article 10. The apparatus air intake 213 is configured to allow ambient air to be drawn into the apparatus housing 207 toward the aerosol forming substrate 11.

Claims

1. Aerosol-generating article, Aerosol-forming substrate and, The aerosol-forming substrate comprises a wrapper surrounding the aerosol-forming substrate, The wrapper defines an overlapping region in which the wrapper overlaps itself, and the overlapping region includes a first section and a second section located externally on the first section. The second section includes a fold that defines the folded section at one end of the wrapper, The folded section is sandwiched between the first section and the second section. An aerosol-generating article in which an outer adhesive is placed between the folded section and the second section.

2. The aerosol-generating article according to claim 1, wherein an internal adhesive is placed between the folded section and the first section.

3. The aerosol-generating article according to claim 1, wherein the outer adhesive comprises one or more of gum arabic, natural resin or synthetic resin, starch, and varnish.

4. The aerosol generating article according to claim 1, further comprising a heating element embedded in the aerosol forming substrate.

5. The aerosol generating article according to claim 4, wherein the heat-generating element is an inductive susceptor.

6. The aerosol generating article according to any one of claims 4 and 5, wherein the heating element is completely surrounded by the aerosol forming substrate and extends along the entire length of the aerosol forming substrate.

7. The aerosol generating article according to any one of claims 1 to 5, wherein the diameter of the aerosol generating article is approximately 3 mm to approximately 8 mm.

8. The aerosol generating article according to any one of claims 1 to 5, wherein the wrapper has a thickness of about 60 micrometers to about 200 micrometers.

9. The aerosol generating article according to any one of claims 1 to 5, wherein the aerosol-forming substrate comprises one or more of tobacco, nicotine, a gel composition, and a flavor substrate.

10. The aerosol generating article according to any one of claims 1 to 5, further comprising a filter disposed downstream of the aerosol forming substrate.

11. The aerosol generating article according to any one of claims 1 to 5, wherein the length of the aerosol generating article is approximately 30 mm to approximately 100 mm.

12. Aerosol generation system, an aerosol generating article according to any one of claims 1 to 5, An aerosol generating system comprising an aerosol generating device.

13. The aerosol generating system according to claim 12, wherein the aerosol generating device comprises a resistance heating element.

14. The aerosol generating system according to claim 12, wherein the aerosol generating device comprises an inductor coil.

Images