AEROSOL-GENERATING PRODUCT WITH NON-IDENTAL INLET AND OUTLET OPENINGS

Abstract

42 ABSTRACT AEROSOL-GENERATING ARTICLE WITH NON-IDENTICAL INLET AND OUTLET There is provided an aerosol-generating article for use with an aerosol-generating device to generate an aerosol. The aerosol-generating article has a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side. The length and the width are greater in magnitude than the thickness. The aerosol-generating article comprises an upper surface, a lower surface, and a substrate cavity located between the upper surface and the lower surface. A first airflow passage extends between the distal end of the article and the cavity. A second airflow passage extends between the cavity and the proximal end of the article. A length of the second airflow passage is greater than a length of the first airflow passage. A minimum transverse cross-sectional area of the first airflow passage is smaller than a minimum transverse cross-sectional area of the second airflow passage. The first airflow passage may be an air inlet and the second airflow passage may be an air outlet. (Figure 11)

Description

[0001] AEROSOL-GENERATING ARTICLE WITH NON-IDENTICAL INLET AND OUTLET

[0002] The present disclosure relates to aerosol-generating articles and aerosol-generating systems comprising the aerosol-generating articles and aerosol-generating devices.

[0003] A typical aerosol-generating article may appear similar to a conventional cigarette. For example, such an aerosol-generating article may be substantially cylindrical and comprise an aerosol-forming substrate and other components such as a mouthpiece filter element and a cooling element, all arranged together in the form of a rod and wrapped in a cigarette paper. Dimensions of typical aerosol-generating articles are often similar to the dimensions of conventional cigarettes.

[0004] However, a significant portion of the aerosol-forming substrate in these cylindrical aerosolgenerating articles may not be sufficiently heated to form an aerosol during use. This is undesirable since the insufficiently heated portion of the aerosol-forming substrate contributes to the cost of manufacture and transport of the aerosol-generating article, but does not contribute to the aerosol delivered to an end user. This may be the case regardless of the way in which the aerosol-forming substrate is heated, for example regardless of whether a resistive or inductive heater is used and regardless of whether the aerosol-forming substrate is heated from the inside or the outside. Moreover, the components of these cylindrical aerosol-generating articles normally need to have the same or very similar outer diameters so that they can be brought together, accurately positioned in co-axial alignment and wrapped in a cigarette paper. This can lead to increased cost and complexity of manufacture.

[0005] Aerosol-generating articles that are relatively “thin” may provide benefits over conventional aerosol-generating articles. It is an aim of the present disclosure to provide improved aerosolgenerating articles, in which a greater portion of an aerosol-forming substrate of the aerosolgenerating article is sufficiently heated to form an aerosol during use. It is also an objective of the present disclosure to provide an aerosol-generating article that can be manufactured relatively efficiently and cheaply. It is also an objective of the present disclosure to provide aerosolgenerating articles optimised for use with aerosol-generating devices.

[0006] According to the present disclosure, there may be provided an aerosol-generating article for use with an aerosol-generating device to generate an aerosol. The aerosol-generating article has a length extending in an x-direction between a distal end and a proximal end. The aerosolgenerating article has a width extending in a y-direction between a left side and a right side. The aerosol-generating article has a thickness extending in a z-direction between an upper side and a lower side. The length and the width of the aerosol-generating article may be greater in magnitude than the thickness. The aerosol-generating article may comprise an upper surface. The aerosol-generating article may comprise a lower surface. The aerosol-generating article may comprise a substrate cavity located between the upper surface and the lower surface. The substrate cavity may extend lengthwise within the article. A midpoint of the substrate cavity may be located closer to the distal end of the article than to the proximal end of the article. The volume of the substrate cavity may between 150 cubic millimetres and 400 cubic millimetres. In preferred examples there may be provided an aerosol-generating article for use with an aerosol-generating device to generate an aerosol, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y- direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width are greater in magnitude than the thickness, the aerosol-generating article comprising: an upper surface; a lower surface; and a substrate cavity located between the upper surface and the lower surface, in which the substrate cavity extends lengthwise within the article and in which a midpoint of the substrate cavity is located closer to the distal end of the article than to the proximal end of the article, in which the volume of the substrate cavity is between 150 cubic millimetres and 400 cubic millimetres.

[0007] According to the present disclosure, there may be provided an aerosol-generating system comprising an aerosol-generating article and an aerosol-generating device configured to receive the aerosol-generating article to generate an aerosol. The aerosol-generating article has a length extending in an x-direction between a distal end and a proximal end. The aerosol-generating article has a width extending in a y-direction between a left side and a right side. The aerosol-generating article has a thickness extending in a z-direction between an upper side and a lower side. The length and the width may be greater in magnitude than the thickness.

[0008] The aerosol-generating device may have an article receiving cavity for receiving the aerosolgenerating article for use. The aerosol-generating article may be asymmetrically shaped such that a distal end of the article may be operationally engaged with the article receiving cavity whereas a proximal end may not.

[0009] In preferred examples there may be provided an aerosol-generating system comprising an aerosol-generating article and an aerosol-generating device configured to receive the aerosolgenerating article to generate an aerosol, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width are greater in magnitude than the thickness, the aerosol-generating device having an article receiving cavity for receiving the aerosol-generating article for use, in which the article is asymmetrically shaped such that a distal end of the article may be operationally engaged with the article receiving cavity whereas a proximal end may not.

[0010] According to the present disclosure, there may be provided an aerosol-generating article for use with an aerosol-generating device to generate an aerosol. The aerosol-generating article has a length extending in an x-direction between a distal end and a proximal end. The aerosolgenerating article has a width extending in a y-direction between a left side and a right side. The aerosol-generating article has a thickness extending in a z-direction between an upper side and a lower side. The length and the width of the article may be greater in magnitude than the thickness of the article. The aerosol-generating article may comprise an upper surface. The aerosol- generating article may comprise a lower surface. The aerosol-generating article may comprise a substrate cavity located between the upper surface and the lower surface. A first airflow passage may extend between the distal end of the article and the cavity. A second airflow passage may extend between the cavity and the proximal end of the article. A length of the second airflow passage may be greater than a length of the first airflow passage. A minimum transverse cross- sectional area of the first airflow passage (in the y-z plane) may be smaller than a minimum transverse cross-sectional area (in the y-z plane) of the second airflow passage.

[0011] In preferred examples there may be provided an aerosol-generating article for use with an aerosol-generating device to generate an aerosol, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y- direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width of the article are greater in magnitude than the thickness of the article, the aerosol-generating article comprising an upper surface; a lower surface; and a substrate cavity located between the upper surface and the lower surface, in which a first airflow passage extends between the distal end of the article and the cavity, and a second airflow passage extends between the cavity and the proximal end of the article, and in which a length of the second airflow passage is greater than a length of the first airflow passage, and in which a minimum transverse cross-sectional area of the first airflow passage (in the y-z plane) is smaller than a minimum transverse cross-sectional area (in the y-z plane) of the second airflow passage.

[0012] An aerosol-generating article according to the present disclosure may comprise a first planar external surface; and a second planar external surface. An aerosol-generating article according to the present disclosure may be referred to as a planar article, and may be relatively “thin”. The thickness of the article may be significantly less than the length or width of the article.

[0013] Advantageously, such articles a may allow for good contact with an external heater, particularly a planar external heater, of an aerosol-generating device, thereby providing optimum heating of the aerosol-generating substrate.

[0014] Advantageously, such articles may provide a large surface area for heating by an external heater of an aerosol-generating device, thereby allowing the aerosol-generating substrate to be quickly heated to a temperature sufficient for generating an aerosol.

[0015] Advantageously, certain examples of aerosol-generating articles of the present disclosure may be manufactured by layering sheet materials which can be achieved through a continuous manufacturing process, thereby resulting in an aerosol-generating article that is relatively easy and cheap to manufacture.

[0016] The substrate cavity may be asymmetrically positioned within the article. The cavity may comprise a substrate cavity distal end and a substrate cavity proximal end. The cavity may comprise a substrate cavity midpoint located half way between the substrate cavity distal end and the substrate cavity proximal end. The substrate cavity may be located asymmetrically with respect to the x-direction of the article such that the substrate cavity midpoint is located closer to the distal end of the article than to the proximal end of the article. The substrate cavity midpoint is the midpoint of the cavity with respect to both length of the cavity and width of the cavity.

[0017] Thus, the substrate cavity may be located closer to a distal end of the article than to a proximal end of the article. If the distal end of the article is inserted into the article receiving cavity of an aerosol-generating device, it is easier for the entire substrate cavity to align with a heater, and therefore be heated, than if the cavity were symmetrically positioned with regard to length of the article.

[0018] The distance between the proximal end of the substrate cavity and the proximal end of the article may be greater than 10 mm, for example greater than 12 mm, for example greater than 15 mm, preferably between 11 mm and 16 mm. The distance between a distal end of the substrate cavity and a distal end of the article may be less than 4 mm, for example less than 3 mm, for example less than 2 mm, preferably between 4 mm and 2 mm.

[0019] Advantageously, the asymmetrical location of the cavity may facilitate handling of the aerosol-generating article during or after heating the aerosol-generating article. This is because the asymmetrical location of the cavity may extend the distance from a proximal end of the aerosolgenerating article to the portion of the aerosol-generating article which is heated. Thus, a larger portion of the aerosol-generating article may be easily gripped during or after the aerosolgenerating article is heated. In particular, this may facilitate removal of the aerosol-generating article after use. Furthermore, the proximal end of the article is less likely to be heated to high temperatures due to the distance from the substrate cavity, meaning that the proximal end of the article is more comfortable to handle immediately after use.

[0020] Advantageously, the asymmetrical location of the cavity with the cavity midpoint located closer to the distal end of the aerosol-generating article may allow for an aerosol-generating device configured to receive the article to have at least one heating element with a reduced length compared to if the if the cavity were centrally located in the article. This is because the distance between the proximal end of the cavity and the distal end of the aerosol-generating article is smaller than if the cavity were centrally located, such that a heating element with reduced length may still be able to heat the entire length of the cavity. This may improve the efficiency of the aerosolgenerating device because a smaller heating element may be used to heat the aerosol-generating substrate in the cavity of the aerosol-generating article.

[0021] A volume of the substrate cavity may be between 150 cubic millimetres and 400 cubic millimetres, for example between 200 cubic millimetres and 380 cubic millimetres, for example between 220 cubic millimetres and 370 cubic millimetres, for example between 250 cubic millimetres and 350 cubic millimetres. A length of the substrate cavity may be between 10 mm and 20 mm, for example between 12 mm and 15 mm, for example about 12 mm, or about 13 mm, or about 14 mm, or about 15 mm. A maximum width of the substrate cavity may be between 6 mm and 10 mm, for example between 7 mm and 8 mm, for example about 7 mm or about 8 mm. An average width of the substrate cavity may be between 6 mm and 10 mm, for example between 7 mm and 8 mm, for example about 7 mm or about 8 mm. A thickness of the substrate cavity may be between 2.5 mm and 3.5 mm, for example between 2.8 mm and 3.2 mm, for example about 2.0 mm, or about 3 mm, or about 3.1 mm.

[0022] Advantageously, the cavity dimensions may provide a large cavity relative to the size of the aerosol-generating article without compromising the structural integrity of the aerosol-generating article.

[0023] The width of the distal end of the substrate cavity may be smaller than a width of the proximal end of the cavity. Alternatively, a width of the distal end of the substrate cavity may be greater than a width of the proximal end of the cavity. The substrate cavity may comprise rounded corners. The radius of the rounded corners may be between 0.5 millimetres and 2 millimetres, for example 1 .5 millimetres.

[0024] The aerosol-generating article may comprise a frame positioned between the upper surface and the lower surface. The frame may have a frame inner surface extending in the z-direction or the transverse direction between the upper surface and the lower surface. The frame may have a frame outer surface extending in the z-direction or the transverse direction between the upper surface and the lower surface. The frame may comprise a peripheral wall circumscribing or encircling the substrate cavity. A peripheral wall may be formed by a frame inner surface and a frame outer surface. The frame inner surface may define a cavity outer wall. The frame outer surface may at least partially define one or more external walls of the aerosol-generating article.

[0025] The frame may have a thickness greater than or equal to 80 percent of the thickness of the aerosol-generating article. The frame may have a thickness between 80 percent and 95 percent of the thickness of the aerosol-generating article. The frame may have a thickness between 1 mm and 4 mm, for example between 2 mm and 3 mm.

[0026] The distance between a side wall of the substrate cavity, for example a left side wall or a right side wall, and a side surface of the article, for example a left side surface or a right side surface, may be less than 2 mm, for example less than 1.5 mm, for example less than 1 mm, preferably between 0.5 mm and 1 .5 mm.

[0027] Advantageously, the distance between the side wall of the substrate cavity and the side surface of the article is small without compromising the structural integrity of the article. Thus, the aerosol-generating article may have a thin peripheral wall around the cavity. This may allow for a larger cavity relative to the dimensions of the aerosol-generating article without compromising the structural integrity of the article.

[0028] The aerosol-generating article may comprise a first airflow passage and a second airflow passage. The first airflow passage may extend between the distal end of the article and the substrate cavity. The second airflow passage may extend between the substrate cavity and the proximal end of the article. The first airflow passage may be an air inlet and the second airflow passage may be an air outlet. Alternatively, the first airflow passage may be an air outlet and the second airflow passage may be an air inlet.

[0029] The length of the first and second airflow passage may extend in the x-dimension of the aerosol-generating article. The width of the first and second airflow passage may extend in the y- dimension of the aerosol-generating article. The thickness of the first and second airflow passage may extend in the z-dimension of the aerosol-generating article.

[0030] The length of the second airflow passage may be greater than the length of the first airflow passage. For example, the length of the second airflow passage may be at least two times greater than the length of the first airflow passage, for example at least three times greater, or at least four times greater, or at least five times greater than the length of the first airflow passage.

[0031] The length of the first airflow passage may be between 1.5 mm and 6 mm, for example between 2 mm and 4 mm. The average width of the first airflow passage may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The minimum width of the first airflow passage may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The average thickness of the first airflow passage may be between 0.75 mm and 2.5 mm, for example between 1 mm and

[0032] 2 mm. The minimum thickness of the first airflow passage may be between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0033] The length of the second airflow passage may be between 10 mm and 20 mm, for example between 11 mm and 16 mm. The average width of the second airflow passage may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The minimum width of the second airflow passage may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The average thickness of the second airflow passage may be between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm. The minimum thickness of the second airflow passage may be between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm. The first airflow passage may be an air inlet. The second airflow passage may be an air outlet. Alternatively, The first airflow passage may be an air outlet and the second airflow passage may be an air inlet.

[0034] The aerosol-generating article may comprise an air inlet and an air outlet. The air inlet may extend between the distal end of the article and the substrate cavity. The air outlet may extend between the substrate cavity and the proximal end of the article. For example, the air inlet may be the first airflow passage and the airflow outlet may be the second airflow passage.

[0035] The length of the air outlet and the length of the air inlet may extend in the x-dimension of the aerosol-generating article. The width of the air outlet and the width of the air inlet may extend in the y-dimension of the aerosol-generating article. The thickness of the air outlet and the thickness of the air inlet may extend in the z-dimension of the aerosol-generating article.

[0036] The length of the air inlet may be between 1 .5 mm and 6 mm, for example between 2 mm and 4 mm. The average width of the air inlet may be between 2mm and 6 mm, for example between

[0037] 3 mm and 5 mm. The minimum width of the air inlet may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The average thickness of the air inlet may be between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm. The minimum thickness of the air inlet may be between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm. A volume of the air inlet may be between 6 cubic millimetres and 40 cubic millimetres.

[0038] The length of the air outlet may be between 10 mm and 20 mm, for example between 11 mm and 16 mm. The average width of the air outlet may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The minimum width of the air outlet may be between 2mm and 6 mm, for example between 3 mm and 5 mm. The average thickness of the air outlet may be between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm. The minimum thickness of the air outlet may between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm. A volume of the air outlet may be between 33 cubic millimetres and 160 cubic millimetres.

[0039] The length of the air outlet is preferably greater than the length of the air inlet. The length of the air outlet may be at least two times greater than the length of the air inlet, for example at least three times greater, or at least four times greater, or at least five times greater than the length of the air outlet.

[0040] Advantageously, a longer air outlet allows for greater cooling of the aerosol before entering a user’s mouth. This is because the longer air outlet increases the surface area of the air outlet through which the heat can dissipate, and extends the time for heat to dissipate from the aerosol between exiting the substrate cavity and entering the user’s mouth.

[0041] The formation of an aerosol by heating an aerosol-forming substrate may result in generation of moisture and slurry. Such moisture and slurry may be drawn towards a user during use of the article. The provision of a relatively long air outlet channel between the substrate cavity and the user may allow for some of this moisture and slurry to be retained by walls of the air outlet and, therefore, not transferred to the user.

[0042] The average width of the air outlet may be greater than the average width of the air inlet. The minimum width of the air outlet may be greater than the minimum width of the air inlet. The maximum width of the air outlet may be greater than the maximum width of the air inlet. The average thickness of the air outlet may be greater than the average thickness of the air inlet. The minimum thickness of the air outlet may be greater than the minimum thickness of the air inlet. The maximum thickness of the air outlet may be greater than the maximum thickness of the air inlet. Thus, an average cross-sectional area of the air inlet may be smaller than an average cross- sectional area of the air outlet.

[0043] Advantageously, having a smaller average air inlet cross-sectional area allows for reduced leakage of the aerosol-generating substrate from the substrate cavity out of the interior surfaces of the air inlet. Although air is drawn into the inlet and out of the outlet, there is also potential for leakage of moisture and slurry from the air inlet into the device during use. Thus, a smaller average air inlet cross-sectional area may help prevent unwanted leakage through the air inlet.

[0044] The air inlet may have a distal end located at the distal end of the article and a proximal end located at an entrance to the cavity. A cross-sectional area of the proximal end of the air inlet may be smaller than a cross-sectional area of the distal end of the air inlet. In other words, the cross- sectional area of the air inlet may be smaller at the cavity than at the distal end of the article. A width of the proximal end of the air inlet may be smaller than a width of the distal end of the air inlet. Alternatively, or in addition, a thickness of the proximal end of the air inlet may be smaller than a thickness of the distal end of the air inlet. The width of the air inlet may decrease between the distal end of the air inlet and the proximal end of the air inlet. The width of the air inlet may decrease continually or decrease linearly. The thickness of the air inlet may decrease between the distal end of the air inlet and the proximal end of the air inlet. The thickness of the air inlet may decrease continually or decrease linearly.

[0045] Alternatively, a cross-sectional area of the proximal end of the air inlet may be greater than a cross-sectional area of the distal end of the air inlet. In other words, the cross-sectional area of the air inlet may be greater at the cavity than at the distal end of the article. A width of the proximal end of the air inlet may be greater than a width of the distal end of the air inlet. Alternatively, or in addition, a thickness of the proximal end of the air inlet may be greater than a thickness of the distal end of the air inlet. The width of the air inlet may increase between the distal end of the air inlet and the proximal end of the air inlet. The width of the air inlet may increase continually or increase linearly. The thickness of the air inlet may increase between the distal end of the air inlet and the proximal end of the air inlet. The thickness of the air inlet may increase continually or increase linearly.

[0046] The air outlet may have a proximal end located at the proximal end of the article and a distal end located at an exit from the cavity. A cross-sectional area of the proximal end of the air outlet may be smaller than a cross-sectional area of the distal end of the air outlet. In other words, the cross-sectional area of the air outlet may be greater at the cavity than at the proximal end of the article. A width of the proximal end of the air outlet may be smaller than a width of the distal end of the air outlet. A thickness of the proximal end of the air outlet may be smaller than a thickness of the distal end of the air outlet. The width of the air outlet may decrease between the distal end of the air outlet and the proximal end of the air outlet. The width of the air outlet may decrease continually or decrease linearly. The thickness of the air outlet may decrease between the distal end of the air outlet and the proximal end of the air outlet. The thickness of the air outlet may decrease continually or decrease linearly.

[0047] A cross-sectional area of the proximal end of the air outlet may be greater than a cross- sectional area of the distal end of the air outlet. In other words, the cross-sectional area of the air outlet may be smaller at the cavity than at the proximal end of the article. A width of the proximal end of the air outlet may be greater than a width of the distal end of the air outlet. A thickness of the proximal end of the air outlet may be greater than a thickness of the distal end of the air outlet. The width of the air outlet may increase between the distal end of the air outlet and the proximal end of the air outlet. The width of the air outlet may increase continually or increase linearly. The thickness of the air outlet may increase between the distal end of the air outlet and the proximal end of the air outlet. The thickness of the air outlet may increase continually or increase linearly.

[0048] A volume to length ratio of the air outlet may be within 20% of a volume to length ratio of the air inlet, for example, within 10% or within 5% or within 1 %. The volume to length ratio of the air outlet may be the same as the volume to length ratio of the air inlet. An average cross-sectional area of the air outlet may be within 20% of an average cross-sectional area of the air inlet, for example, within 10% or within 5% or within 1 %. The average cross-sectional area of the air outlet may be the same as the average cross-sectional area of the air inlet.

[0049] Alternatively, the average cross-sectional area of the air outlet may be greater that the average cross-sectional area of the air inlet. A volume to average cross-sectional area ratio of the air outlet may be within 20% of a volume to average cross-sectional area ratio of the air inlet, for example, within 10% or within 5% or within 1 %. The volume to average cross-sectional area ratio of the air outlet may be the same as the volume to average cross-sectional area ratio of the air inlet.

[0050] An external shape of the aerosol-generating article may be asymmetrical. The external shape of the article may be asymmetrical in the x-direction. For example, a distal portion of the article may be shaped differently to a proximal portion of the article. The distal portion of the article may be tapered. The distal portion of the article may be tapered in its width dimension. For example, a minimum width in the proximal portion of the article may greater than a minimum width in the distal portion of the article.

[0051] The width of the article, taken in the y-dimension, at a point 3 mm from the distal end of the article may be smaller than a width, taken in the y-dimension, at a point 3 mm from the proximal end of the article, for example between 1% and 15% smaller, for example between 2% and 10% smaller.

[0052] Advantageously, the width at a point 3 mm from the distal end of the aerosol-generating article being within 15% of the width at a point 3 mm from the proximal end of the aerosolgenerating article allows the aerosol-generating article to be manufactured more easily. Thus, sides of the article may taper slightly when approaching the distal end. By providing asymmetry with a slight taper of the distal portion of the article, the volume of the substrate cavity, located in the distal portion of the article, may not be compromised to a great degree. Thus, the load of aerosol-generating substrate cam be maximised while still providing a one-way insertion of the article into the device. Furthermore, if the width of the article at the distal end is no less than, for example 15% of the width of the article at the proximal end, the ability to manufacture the articles in a cost and material efficient manner may be optimised.

[0053] The external shape of the article may be mechanically configured such that a distal end of the article may be inserted into an aerosol-generating device whereas a proximal end may not. Advantageously, this facilitates insertion of the article into an aerosol-generating device in the correct orientation. The aerosol-generating article may comprise a left side face and a right side face. The cavity may be located between the left side face and the right side face. The article may comprise a proximal end surface and a distal end surface, the cavity being located between the proximal end surface and the distal end surface.

[0054] The aerosol-generating article may comprise a first distal corner and a second distal corner. The first and second distal corners may be defined between the distal end surface and the left side surface and the right side face respectively. The first and second distal corners may be rounded corners. The aerosol-generating article may comprise a first proximal corner and a second proximal corner. The first and second proximal corners may be defined between the proximal end surface and the left side surface and the right side face respectively. The first and second proximal corners may be rounded corners. The first and second distal corners may have a smaller radius than the first and second proximal corners. The first and second distal corners may have a radius of between 0.5 mm and 2 mm, for example about 1 mm. The first and second proximal corners may have a radius of between 1 mm and 3 mm, for example about 2 mm. The first and second distal corners may have a smaller radius than the first and second proximal corners. Thus, the proximal end surface may be wider than the distal end surface. This may advantageously prevent a user from being able to insert the proximal end of the article first into an aerosol-generating device.

[0055] Air may flow into the aerosol-generating article through the distal end surface, through the substrate cavity, and out of the article through the proximal end surface. For example, air may through an inlet defined in the distal end surface, through the substrate cavity, and out of an outlet defined through the proximal end surface.

[0056] The aerosol-generating article may comprise one or more aerosol-generating substrates. At least one of the one or more aerosol-generating substrates may be positioned within the cavity. The aerosol-generating substrate positioned within the cavity may comprise tobacco cut filler. Alternatively, or in addition, the aerosol-generating substrate positioned within the cavity may be in the form of a plurality of free-flowing beads of aerosol-forming material, for example a plurality of discrete free-flowing beads having an average bead diameter of between 0.1 mm and 4 mm, preferably between 1 mm and 2 mm, for example between 1 .2 mm and 1 .7 mm.

[0057] The term “bead” refers to a discrete, solid particle formed of the aerosol-generating substrate. A bead may have a rounded, typically spherical, form. Rounded or spherical beads have a low contact area with other beads and a plurality of such beads may have good flowability. This means that a mass or volume of such beads may be capably of flowing freely. The ability of a plurality of beads to flow, or be poured, may be highly advantageous in providing a consistent dose of substrate during manufacture. Other terms may be used to define the substrate such as, for example, “granule”.

[0058] Beads can be easily handled compared to other aerosol-forming substrates such as fine powders or cut filler. The beads flow easily, and so can reliably and consistently fill the cavity of the aerosol-generating article during manufacture. Cut filler in particular cannot be reliably and repeatably poured into the cavity of an article. This may allow a consistent and reproducible amount of aerosol-forming substrate to be loaded into each article during manufacture. Beads may also be cleaner to handle than powders and cut fillers, which may cause dust in factories, and may leak from aerosol-generating articles in transit or in use. By selecting beads with appropriate bead sizes and appropriate particle size distributions, air flow through the cavity of the aerosol-generating article may be controlled more reproducibly than would be the case for, say, a cut filler substrate. It is noted that the plurality of beads referred to herein are a plurality of discrete beads, that is the beads are not bound to each other with a binder or matrix phase.

[0059] Where a particle is not perfectly spherical, but a diameter of the particle is referred to, the term “diameter” may refer to a largest dimension of the particle. Alternatively, the term “diameter” may refer to the diameter of a perfectly spherical particle having the same volume as the not perfectly spherical particle.

[0060] The term “average particle diameter”, as used herein, may refer to a number average particle diameter. Other methods of determining average particle diameter are known. Thus, the average particle diameter may be, for example, a volume average particle diameter.

[0061] Unless otherwise mentioned, values given for average particle diameters in this specification refer to a “number average particle diameter”. Specifically, a “number average particle diameter” is calculated as a sum of the diameters of the particles in a group divided by the number of particles in the group. Mathematically, this can be expressed as:

[0062] In the above equation, N is the total number of particles, and Dnis the diameter of the nthparticle.

[0063] Each of the plurality of beads may be defined in terms of a maximum dimension (dmax) and a minimum dimension (dmin). Preferably, the plurality of beads has an average dmax of less than 4 mm, for example less than 3 mm. Preferably, the plurality of beads has an average dmin of greater than 0.5 mm, for example greater than 0.75 mm. The bead dimensions are selected such that the beads flow easily and such that the volume of the beads is not so great that volatile components cannot be substantially completely liberated from each bead on heating for a short duration of time. The beads may be substantially spherical. The beads may be non-spherical, but in this case, they are preferably of low aspect ratio, for example ovoid, such that the beads still flow easily.

[0064] The aerosol-generating substrate may comprise aerosol-generating material. The aerosol-generating material may be in the form of shredded aerosol-generating material. The shredded aerosol-generating material comprises one or more of: strips and strands of aerosolgenerating material, such as strips and strands of tobacco or homogenised tobacco material.

[0065] The aerosol-generating substrate positioned within the cavity may have a mass of between 50 milligrams and 500 milligrams. For example, the aerosol-generating substrate positioned within the cavity may have a mass of between 100 milligrams and 350 milligrams, for example between 130 milligrams and 230 milligrams.

[0066] The length of the article may be greater or equal to the width of the article. The width of the article may be at least 2 times the thickness of the article, for example at least 3 times the thickness, for example at least 3.5 times the thickness, or at least 4 times the thickness. Thus, the thickness of the aerosol-generating article may be less than 50 percent of both a length and a width of the aerosol-generating article. Advantageously, this increases the heating surface area of the aerosolgenerating article in the x-y plane, which may allow for more even heat distribution through the article.

[0067] The length of the article may be between 25 mm and 35 mm, for example between 29 mm and 31 mm, for example about 30 mm. The width of the article may be between 8 mm and 15 mm, for example between 10 mm and 12 mm, for example about 11 mm. The thickness of the article may between 2.5 mm and 3.5 mm, for example between 2.9 mm and 3.3 mm, for example about 3.1 mm, or 3.2 mm, or 3.3 mm.

[0068] According to the present disclosure, there may be provided an aerosol-generating system comprising an aerosol-generating article as described above and an aerosol-generating device configured to receive the aerosol-generating article to generate an aerosol. The aerosol-generating device comprises an article receiving cavity. The aerosol-generating article may be asymmetrically shaped such that a distal end of the article may be operationally engaged with the article receiving cavity whereas a proximal end may not. The width of a distal portion of the article may be smaller than a width of a proximal portion of the article. The article receiving cavity may be dimensioned to receive the article when a distal end of the article is inserted but not when a proximal end of the article is inserted. An internal shape of the article receiving cavity may be configured to mate with an external shape of a proximal portion of the aerosol-generating article when the article is operationally engaged with the article receiving cavity. The article may have rounded distal corners and the article receiving cavity may comprise a distal end having rounded corners to engage with the distal end of the aerosol-generating article.

[0069] As used herein, the term “aerosol-generating article” may refer to an article able to generate, or release, an aerosol.

[0070] As used herein, the term “aerosol-forming substrate” may refer to a substrate capable of releasing an aerosol or volatile compounds that can form an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. An aerosol-forming substrate may comprise an aerosol-forming material. An aerosol-forming substrate may be adsorbed, coated, impregnated, or otherwise loaded onto a carrier or support. As used herein, the term “aerosol-generating device” may refer to a device for use with an aerosol-generating article to enable the generation, or release, of an aerosol.

[0071] As used herein, the term “aerosol generating system” refers to a combination of an aerosolgenerating device and one or more aerosol-forming articles for use with the device. An aerosolgenerating system may include additional components, such as a charging unit for recharging an on-board electric power supply in an electrically operated or electric aerosol-generating device.

[0072] As used herein, the term “aerosol former” may refer to any suitable known compound or mixture of compounds that, in use, facilitates formation of an aerosol. The aerosol may be a dense and stable aerosol. The aerosol may be substantially resistant to thermal degradation at the operating temperature of the aerosol-forming substrate or aerosol-generating article.

[0073] As used herein with reference to the invention, the term “nicotine”, is used to describe nicotine, nicotine base or a nicotine salt.

[0074] As used herein with reference to the invention, the terms “proximal”, “distal”, “upstream” and “downstream” are used to describe the relative positions of components, or portions of components, of the aerosol-generating article.

[0075] As used herein, the term “longitudinal” refers to the direction corresponding to the main longitudinal axis of the aerosol-generating article, which extends between the upstream and downstream ends of the aerosol-generating article. During use, air may be drawn through the aerosol-generating article in the longitudinal direction.

[0076] As used herein, the term “sheet” denotes a laminar element having a width and length substantially greater than the thickness thereof. The width of a sheet may be greater than 10 mm, preferably greater than 20 mm or 30 mm. In certain embodiments, sheets of material for use in forming aerosol-forming substrates as described herein may have a thickness of between 10 pm and about 1000 pm, for example between 10 pm and about 300 pm.

[0077] As used herein, the term “homogenised tobacco material” encompasses any tobacco material formed by the agglomeration of particles of tobacco material. Sheets or webs of homogenised tobacco material are formed by agglomerating particulate tobacco obtained by grinding or otherwise powdering of one or both of tobacco leaf lamina and tobacco leaf stems. In addition, homogenised tobacco material may comprise a minor quantity of one or more of tobacco dust, tobacco fines, and other particulate tobacco by-products formed during the treating, handling and shipping of tobacco. The sheets of homogenised tobacco material may be produced by casting, extrusion, paper making processes or other any other suitable processes known in the art.

[0078] The term “cast leaf” is used herein to refer to a product made by a casting process that is based on casting a slurry comprising plant particles (for example, clove particles or tobacco particles and clove particles in a mixture) and a binder (for example, guar gum) onto a supportive surface, such as a belt conveyor, drying the slurry and removing the dried sheet from the supportive surface. An example of the casting or cast leaf process is described in, for example, US-A- 5,724,998 for making cast leaf tobacco. In a cast leaf process, particulate plant materials are produced by pulverizing, grinding, or comminuting parts of the plant. The particles produced from one or more plants are mixed with a liquid component, typically water, to form a slurry. Other components in the slurry may include fibres, a binder and an aerosol former. The particulate plant materials may be agglomerated in the presence of the binder. The slurry is cast onto a supportive surface and dried into a sheet of homogenized plant material. Preferably, homogenized plant material used in articles according to the present invention may be produced by casting. Such homogenized plant material may comprise agglomerated particulate plant material.

[0079] As used herein, the term “particle size” may refer to a single dimension and may be used to characterise the size of a given particle. The dimension may be the diameter of a spherical particle occupying the same volume as the given particle. All particle sizes and particle size distributions herein can be obtained using a standard laser diffraction technique. Particle sizes and particle size distributions as stated herein may be obtained using a commercially available sensor, for example a Sympatec HELOS laser diffraction sensor.

[0080] As used herein, where not otherwise specified, the term “density” may be used to refer to true density. Thus, where not otherwise specified, the density of a powder or plurality of particles may refer to the true density of the powder or plurality of particles (rather than the bulk density of the powder or plurality of particles, which can vary greatly depending on how the powder or plurality of particles are handled). The measurement of true density can be done using a number of standard methods, these methods often being based on Archimedes’ principle. The most widely used method, when used to measure the true density of a powder, includes the powder being placed inside a container (a pycnometer) of known volume, and weighed. The pycnometer is then filled with a fluid of known density, in which the powder is not soluble. The volume of the powder is determined by the difference between the volume as shown by the pycnometer, and the volume of liquid added (i.e. the volume of air displaced).

[0081] The invention is defined in the claims. However, below there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0082] Exi. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width are greater in magnitude than the thickness, the aerosol-generating article comprising a substrate cavity, in which the substrate cavity extends lengthwise within the article.

[0083] Exii. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating article according to Exi, the aerosol-generating article comprising: a first planar external surface; and a second planar external surface, and a cavity located between the first planar external surface; and the second planar external surface. Exiii. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating article according to Exi or Exii, the aerosolgenerating article comprising one or more aerosol-forming substrates located in a substrate cavity, the aerosol-generating article comprising a first planar external surface and a second planar external surface.

[0084] Exiv. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating article according to any preceding example, the aerosol-generating article having a base defined by an x dimension extending in an x direction and a y dimension extending in a y direction, and a height defined by a z dimension extending in a z direction, a cavity being located within the article.

[0085] Exv. An aerosol-generating article for use with an aerosol-generating device to generate an inhalable aerosol, for example an aerosol-generating article according to any preceding example, the aerosol-generating article comprising an article upstream end, or distal end, and an article downstream end, or proximal end, wherein an article air flow path and an article length extend from the article upstream end / distal end to the article downstream end / proximal end.

[0086] Exvi. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating article according to any preceding example, the aerosol-generating article comprising: a first planar external surface; a second planar external surface; a cavity; a frame positioned between the first planar external surface and the second planar external surface, the frame at least partially defining the cavity; one or more aerosolgenerating substrates; and an air inlet and an air outlet, an airflow passage extending between the air inlet and the air outlet through the cavity.

[0087] Exvii. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating article according to any preceding example, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width are greater in magnitude than the thickness, the aerosol-generating article comprising a substrate cavity, in which the substrate cavity extends lengthwise within the article and in which a midpoint of the substrate cavity is located closer to the distal end of the article than to the proximal end of the article.

[0088] Ex1 . An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating device according to any preceding example, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width are greater in magnitude than the thickness, the aerosol-generating article comprising: an upper surface; a lower surface; and a substrate cavity located between the upper surface and the lower surface, in which the substrate cavity extends lengthwise within the article and in which a midpoint of the substrate cavity is located closer to the distal end of the article than to the proximal end of the article.

[0089] Ex2. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating device according to any preceding example, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, the aerosol-generating article comprising: an upper surface; a lower surface; and a substrate cavity located between the upper surface and the lower surface, in which the substrate cavity is asymmetrically positioned within the article.

[0090] Ex3. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating device according to any preceding example, or the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, the aerosol-generating article comprising: an upper surface; a lower surface; and a substrate cavity located between the upper surface and the lower surface, in which the substrate cavity extends lengthwise within the article in the x-direction between a substrate cavity distal end and a substrate cavity proximal end, a substrate cavity midpoint being located half way between the substrate cavity distal end and the substrate cavity proximal end, and in which the substrate cavity is located asymmetrically with respect to the x-direction of the article such that the substrate cavity midpoint is located closer to the distal end of the article than to the proximal end of the article.

[0091] Ex3A. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating device according to any preceding example, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width of the article are greater in magnitude than the thickness of the article, the aerosol-generating article comprising: an upper surface; a lower surface; and a substrate cavity located between the upper surface and the lower surface, in which a first airflow passage extends between the distal end of the article and the cavity, and a second airflow passage extends between the cavity and the proximal end of the article, and in which a length of the second airflow passage is greater than a length of the first airflow passage, and in which a minimum transverse cross-sectional area of the first airflow passage (i.e. in the y- z plane) is smaller than a minimum transverse cross-sectional area (i.e. in the y-z plane) of the second airflow passage.

[0092] Ex4. An aerosol-generating article according to any preceding example in which a volume of the substrate cavity is between 150 cubic millimetres and 400 cubic millimetres, for example between 200 cubic millimetres and 380 cubic millimetres, for example between 220 cubic millimetres and 370 cubic millimetres, for example between 250 cubic millimetres and 350 cubic millimetres.

[0093] Ex5. An aerosol-generating article according to any preceding example in which a length of the substrate cavity is between 10 mm and 20 mm, for example between 12 mm and 15 mm, for example about 12 mm, or about 13 mm, or about 14 mm, or about 15 mm.

[0094] Ex6. An aerosol-generating article according to any preceding example in which a maximum width of the substrate cavity is between 6 mm and 10 mm, for example between 7 mm and 8 mm, for example about 7 mm or about 8 mm.

[0095] Ex7. An aerosol-generating article according to any preceding example in which an average width of the substrate cavity is between 6 mm and 10 mm, for example between 7 mm and 8 mm, for example about 7 mm or about 8 mm.

[0096] Ex8. An aerosol-generating article according to any preceding example in which a thickness of the substrate cavity is between 2.5 mm and 3.5 mm, for example between 2.8 mm and 3.2 mm, for example about 2.0 mm, or about 3 mm, or about 3.1 mm.

[0097] Ex9. An aerosol-generating article according to any preceding example, in which the substrate cavity comprises a proximal end and a distal end.

[0098] Ex10. An aerosol-generating article according to Ex9, in which a width of the distal end of the substrate cavity is smaller than a width of the proximal end of the cavity.

[0099] Ex11 . An aerosol-generating article according to Ex9, in which a width of the distal end of the substrate cavity is greater than a width of the proximal end of the cavity.

[0100] Ex12. An aerosol-generating article according to any preceding example, the article comprising an upper surface, a lower surface, and a frame positioned between the upper surface and the lower surface. Ex13. An aerosol-generating article according to Ex12 in which the frame has a frame inner surface extending in the z-direction or the transverse direction between the upper surface and the lower surface.

[0101] Ex14. An aerosol-generating article according to Ex12 or 13 in which the frame has a frame outer surface extending in the z-direction or the transverse direction between the upper surface and the lower surface.

[0102] Ex15. An aerosol-generating article according to any of examples 12 to 14 wherein the frame comprises a peripheral wall circumscribing or encircling the substrate cavity.

[0103] Ex16. An aerosol-generating article according to any of examples 12 to 15 wherein a peripheral wall is formed by a frame inner surface and a frame outer surface, and wherein the frame inner surface defines a cavity outer wall and the frame outer surface at least partially defines one or more external walls of the aerosol-generating article.

[0104] Ex17. An aerosol-generating article according to any of examples 12 to 16 wherein the frame has a thickness greater than or equal to 80 percent of the thickness of the aerosol-generating article.

[0105] Ex18. An aerosol-generating article according to any of examples 12 to 17 wherein the frame has a thickness between 80 percent and 95 percent of the thickness of the aerosolgenerating article.

[0106] Ex19. An aerosol-generating article according to any of examples 12 to 18 wherein the frame has a thickness between 1 mm and 4 mm, for example between 2 mm and 3 mm.

[0107] Ex20. An aerosol-generating article according to any preceding example in which the distance between a proximal end of the substrate cavity and a proximal end of the article is greater than 10 mm, for example greater than 12 mm, for example greater than 15 mm, preferably between 11 mm and 16 mm.

[0108] Ex20A. An aerosol-generating article according to any preceding example in which the distance between a side wall of the substrate cavity, for example a left side wall or a right side wall, and a side surface of the article, for example a left side surface or a right side surface, is less than 2 mm, for example less than 1 .5 mm, for example less than 1 mm, preferably between 0.5 mm and 1 .5 mm.

[0109] Ex21 . An aerosol-generating article according to any preceding example in which the distance between a distal end of the substrate cavity and a distal end of the article is less than 4 mm, for example less than 3 mm, for example less than 2 mm, preferable between 4 mm and 2 mm.

[0110] Ex21 A. An aerosol-generating article according to any preceding example in which the article comprises a first airflow passage, the first airflow passage extending between the distal end of the article and the substrate cavity, and a second airflow passage, the second airflow passage extending between the substrate cavity and the proximal end of the article. Ex21 B. An aerosol-generating article according to any preceding example in which the first airflow passage is an air inlet and the second airflow passage is an air outlet.

[0111] Ex21 C. An aerosol-generating article according to any preceding example in which the first airflow passage is an air outlet and the second airflow passage is an air inlet.

[0112] Ex21 D. An aerosol-generating article according to any of Ex21 A to Ex21 C in which the length of the second airflow passage is greater than the length of the first airflow passage, for example in which the length of the second airflow passage is at least two times greater than the length of the first airflow passage, for example at least three times greater, or at least four times greater, or at least five times greater than the length of the first airflow passage.

[0113] Ex21 E. An aerosol-generating article according to any of examples Ex21A to Ex21 D in which the length of the first airflow passage is between 1 .5 mm and 6 mm, for example between 2 mm and 4 mm.

[0114] Ex21 F. An aerosol-generating article according to any of examples Ex21A to Ex21 E in which the average width of the first airflow passage is between 2mm and 6 mm, for example between 3 mm and 5 mm.

[0115] Ex21 G. An aerosol-generating article according to any of examples Ex21A to Ex21 F in which the minimum width of the first airflow passage is between 2mm and 6 mm, for example between 3 mm and 5 mm.

[0116] Ex21 H. An aerosol-generating article according to any of examples Ex21A to Ex21 G in which the average thickness of the first airflow passage is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0117] Ex21 l. An aerosol-generating article according to any of examples Ex21A to Ex21 H in which the minimum thickness of the first airflow passage is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0118] Ex21J. An aerosol-generating article according to any of examples Ex21A to Ex21 l in which the length of the second airflow passage is between 10 mm and 20 mm, for example between 11 mm and 16 mm.

[0119] Ex21 K. An aerosol-generating article according to any of examples Ex21A to Ex21J in which the average width of the second airflow passage is between 2mm and 6 mm, for example between 3 mm and 5 mm.

[0120] Ex21 L. An aerosol-generating article according to any of examples Ex21A to Ex21 K in which the minimum width of the second airflow passage, taken in the y-dimension of the aerosolgenerating article, is between 2mm and 6 mm, for example between 3 mm and 5 mm.

[0121] Ex21 M. An aerosol-generating article according to any of examples Ex21A to Ex21 L in which the average thickness of the second airflow passage is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0122] Ex21J. An aerosol-generating article according to any of examples Ex21A to Ex21 l in which the minimum thickness of the second airflow passage, taken in the z-dimension of the aerosol-generating article, is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0123] Ex22. An aerosol-generating article according to any preceding example in which the article comprises an air inlet, the air inlet extending between the distal end of the article and the substrate cavity, and an air outlet, the air outlet extending between the substrate cavity and the proximal end of the article, for example in which the air inlet is the first airflow passage of Ex21A and the airflow outlet is the second airflow passage of Ex21 A.

[0124] Ex23. An aerosol-generating article according to Ex22 in which the length of the air outlet is greater than the length of the air inlet, for example in which the length of the air outlet and the length of the air inlet extend in the x-dimension of the aerosol-generating article.

[0125] Ex24. An aerosol-generating article according to Ex22 or Ex 23 in which the length of the air outlet is at least two times greater than the length of the air inlet, for example at least three times greater, or at least four times greater, or at least five times greater than the length of the air outlet.

[0126] Ex25. An aerosol-generating article according to any of examples Ex22 to Ex24 in which the length of the air inlet is between 1 .5 mm and 6 mm, for example between 2 mm and 4 mm.

[0127] Ex26. An aerosol-generating article according to any of examples Ex22 to Ex25 in which the average width of the air inlet is between 2mm and 6 mm, for example between 3 mm and 5 mm, for example in which the width of the air outlet and the width of the air inlet extend in the y- dimension of the aerosol-generating article.

[0128] Ex26A. An aerosol-generating article according to any of examples Ex22 to Ex25 in which the minimum width of the air inlet, taken in the y-dimension of the aerosol-generating article, is between 2mm and 6 mm, for example between 3 mm and 5 mm.

[0129] Ex27. An aerosol-generating article according to any of examples Ex22 to Ex26A in which the average thickness of the air inlet is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm, for example in which the thickness of the air outlet and the thickness of the air inlet extend in the z-dimension of the aerosol-generating article.

[0130] Ex27A. An aerosol-generating article according to any of examples Ex22 to Ex26A in which the minimum thickness of the air inlet, taken in the z-dimension of the aerosol-generating article, is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0131] Ex28. An aerosol-generating article according to any of examples Ex22 to Ex27A in which the length of the air outlet is between 10 mm and 20 mm, for example between 11 mm and 16 mm.

[0132] Ex29. An aerosol-generating article according to any of examples Ex22 to Ex28 in which the average width of the air outlet is between 2mm and 6 mm, for example between 3 mm and 5 mm.

[0133] Ex29A. An aerosol-generating article according to any of examples Ex22 to Ex29 in which the minimum width of the air outlet, taken in the y-dimension of the aerosol-generating article, is between 2mm and 6 mm, for example between 3 mm and 5 mm. Ex30. An aerosol-generating article according to any of examples Ex22 to Ex29A in which a volume of the air outlet is between 33 cubic millimetres and 160 cubic millimetres.

[0134] Ex31 . An aerosol-generating article according to any of examples Ex22 to Ex30 in which a volume of the air inlet is between 6 cubic millimetres and 40 cubic millimetres.

[0135] Ex32. An aerosol-generating article according to any of examples Ex22 to Ex31 in which the average thickness of the air outlet is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0136] Ex32A. An aerosol-generating article according to any of examples Ex22 to Ex32 in which the minimum thickness of the air outlet, taken in the z-dimension of the aerosol-generating article, is between 0.75 mm and 2.5 mm, for example between 1 mm and 2 mm.

[0137] Ex33. An aerosol-generating article according to any of examples Ex22 to Ex32A in which the average width of the air outlet is greater than the average width of the air inlet.

[0138] Ex33A. An aerosol-generating article according to any of examples Ex22 to Ex33 in which the minimum width of the air outlet is greater than the minimum width of the air inlet.

[0139] Ex34. An aerosol-generating article according to any of examples Ex22 to Ex33A in which the maximum width of the air outlet is greater than the maximum width of the air inlet.

[0140] Ex35. An aerosol-generating article according to any of examples Ex22 to Ex34 in which the average thickness of the air outlet is greater than the average thickness of the air inlet.

[0141] Ex35A. An aerosol-generating article according to any of examples Ex22 to Ex35 in which the minimum thickness of the air outlet is greater than the minimum thickness of the air inlet.

[0142] Ex36. An aerosol-generating article according to any of examples Ex22 to Ex35A in which the maximum thickness of the air outlet is greater than the maximum thickness of the air inlet.

[0143] Ex37. An aerosol-generating article according to any of examples Ex22 to Ex36 in which the air inlet has a distal end located at the distal end of the article and a proximal end located at an entrance to the cavity.

[0144] Ex37A. An aerosol-generating article according to Ex37 in which a cross-sectional area of the proximal end of the air inlet is smaller than a cross-sectional area of the distal end of the air inlet, i.e. the cross-sectional area of the air inlet is smaller at the cavity than at the distal end of the article.

[0145] Ex37B. An aerosol-generating article according to Ex37 or Ex37A in which a width of the proximal end of the air inlet is smaller than a width of the distal end of the air inlet.

[0146] Ex37C. An aerosol-generating article according to Ex37 or Ex37A in which a thickness of the proximal end of the air inlet is smaller than a thickness of the distal end of the air inlet.

[0147] Ex38. An aerosol-generating article according to Ex37 to Ex37C in which a width of the air inlet increases, for example increases continually or increases linearly, between the distal end of the air inlet and the proximal end of the air inlet. Ex39. An aerosol-generating article according to Ex37 to Ex38 in which a thickness of the air inlet increases, for example increases continually or increases linearly, between the distal end of the air inlet and the proximal end of the air inlet.

[0148] Ex40. An aerosol-generating article according to Ex37 in which a cross-sectional area of the proximal end of the air inlet is greater than a cross-sectional area of the distal end of the air inlet, i.e. the cross-sectional area of the air inlet is greater at the cavity than at the distal end of the article.

[0149] Ex40A. An aerosol-generating article according to Ex37 or Ex40 in which a width of the proximal end of the air inlet is greater than a width of the distal end of the air inlet.

[0150] Ex40B. An aerosol-generating article according to Ex37, Ex40, or Ex40A in which a thickness of the proximal end of the air inlet is greater than a thickness of the distal end of the air inlet.

[0151] Ex41 . An aerosol-generating article according to Ex37 in which a width of the air inlet decreases, for example decreases continually or decreases linearly, between the distal end of the air inlet and the proximal end of the air inlet.

[0152] Ex42. An aerosol-generating article according to Ex37 or Ex41 in which a thickness of the air inlet decreases, for example decreases continually or decreases linearly, between the distal end of the air inlet and the proximal end of the air inlet.

[0153] Ex43. An aerosol-generating article according to any of examples Ex22 to Ex42 in which the air outlet has a proximal end located at the proximal end of the article and a distal end located at an exit from the cavity.

[0154] Ex44. An aerosol-generating article according to Ex43 in which a cross-sectional area of the proximal end of the air outlet is smaller than a cross-sectional area of the distal end of the air outlet, i.e. the cross-sectional area of the air outlet is greater at the cavity than at the proximal end of the article.

[0155] Ex44B. An aerosol-generating article according to Ex43 or Ex44 in which a width of the proximal end of the air outlet is smaller than a width of the distal end of the air outlet.

[0156] Ex44C. An aerosol-generating article according to any of examples Ex43 to Ex44B in which a thickness of the proximal end of the air outlet is smaller than a thickness of the distal end of the air outlet.

[0157] Ex45. An aerosol-generating article according to Ex43 to Ex44C in which a width of the air outlet increases, for example increases continually or increases linearly, between the proximal end of the air outlet and the distal end of the air outlet.

[0158] Ex46. An aerosol-generating article according to Ex43 to Ex45 in which a thickness of the air outlet increases, for example increases continually or increases linearly, between the proximal end of the air outlet and the distal end of the air outlet.

[0159] Ex47. An aerosol-generating article according to Ex43 in which a cross-sectional area of the proximal end of the air outlet is greater than a cross-sectional area of the distal end of the air outlet, i.e. the cross-sectional area of the air outlet is smaller at the cavity than at the proximal end of the article.

[0160] Ex47A. An aerosol-generating article according to Ex43 or Ex47 in which a width of the proximal end of the air outlet is greater than a width of the distal end of the air outlet.

[0161] Ex47B. An aerosol-generating article according to Ex43, Ex47, or Ex47A in which a thickness of the proximal end of the air outlet is greater than a thickness of the distal end of the air outlet.

[0162] Ex48. An aerosol-generating article according to Ex43 in which a width of the air outlet decreases, for example decreases continually or decreases linearly, between the proximal end of the air outlet and the distal end of the air outlet.

[0163] Ex48A. An aerosol-generating article according to Ex43 or Ex48 in which a thickness of the air outlet decreases, for example decreases continually or decreases linearly, between the proximal end of the air outlet and the distal end of the air outlet.

[0164] Ex49. An aerosol-generating article according to any of Ex21A to Ex48A in which a volume to length ratio of the air outlet is within 20% of a volume to length ratio of the air inlet, for example, within 10% or within 5% or within 1 %.

[0165] Ex50. An aerosol-generating article according to any of Ex21A to Ex49 in which the volume to length ratio of the air outlet is the same as the volume to length ratio of the air inlet.

[0166] Ex51. An aerosol-generating article according to any of Ex21A to Ex50 in which an average cross-sectional area of the air outlet is within 20% of an average cross-sectional area of the air inlet, for example, within 10% or within 5% or within 1 %.

[0167] Ex52. An aerosol-generating article according to any of Ex21A to Ex51 in which the average cross-sectional area of the air outlet is the same as the average cross-sectional area of the air inlet.

[0168] Ex53. An aerosol-generating article according to any of Ex21A to Ex52 in which the average cross-sectional area of the air outlet is greater that the average cross-sectional area of the air inlet.

[0169] Ex54. An aerosol-generating article according to any of Ex21 A to Ex53 in which a volume to average cross-sectional area ratio of the air outlet within 20% of a volume to average cross- sectional area ratio of the air inlet, for example, within 10% or within 5% or within 1 %.

[0170] Ex55. An aerosol-generating article according to any of Ex21 A to Ex54 in which a volume to average cross-sectional area ratio of the air outlet is the same as the volume to average cross- sectional area ratio of the air inlet.

[0171] Ex56. An aerosol-generating article according to any preceding example in which an external shape of the article is asymmetrical.

[0172] Ex57. An aerosol-generating article according to any preceding example in which an external shape of the article is asymmetrical in the x-direction, for example in which a distal portion of the article is shaped differently to a proximal portion of the article. Ex58. An aerosol-generating article according to Ex57 in which the distal portion of the article is tapered, for example tapered in its width dimension, for example in which a minimum width in the proximal portion of the article is greater than a minimum width in the distal portion of the article.

[0173] Ex59. An aerosol-generating article according to Ex57 or Ex58 in which the width of the article, taken in the y-dimension, at a point 3 mm from the distal end of the article is smaller than a width, taken in the y-dimension, at a point 3 mm from the proximal end of the article, for example between 1% and 15% smaller, for example between 2% and 10% smaller.

[0174] Ex60. An aerosol-generating article according to any preceding example in which an external shape of the article is mechanically configured such that a distal end of the article may be inserted into an aerosol-generating device whereas a proximal end may not.

[0175] Ex61. An aerosol-generating article according to any preceding example in which the article comprises a left side face and a right side face, the cavity being located between the left side face and the right side face.

[0176] Ex62. An aerosol-generating article according to any preceding example in which the article comprises a proximal end surface and a distal end surface, the cavity being located between the proximal end surface and the distal end surface.

[0177] Ex63. An aerosol-generating article according to Ex61 and Ex62 in which first and second distal corners, defined between the distal end surface and the left side surface and the right side face respectively, are rounded corners.

[0178] Ex64. An aerosol-generating article according to Ex61 and Ex62 in which first and second proximal corners, defined between the proximal end surface and the left side surface and the right side surface respectively, are rounded corners.

[0179] Ex65. An aerosol-generating article according to Ex63 and Ex64 in which the first and second distal corners have a smaller radius than the first and second proximal corners.

[0180] Ex66. An aerosol-generating article according to any of Ex63 to Ex65 in which the first and second distal corners have a radius of between 0.5 mm and 2 mm, for example about 1 mm.

[0181] Ex67. An aerosol-generating article according to any of Ex63 to Ex66 in which the first and second proximal corners have a radius of between 1 mm and 3 mm, for example about 2 mm.

[0182] Ex68. An aerosol-generating article according to any preceding example, comprising one or more aerosol-generating substrates.

[0183] Ex69. An aerosol-generating article according to Ex68, wherein at least one of the one or more aerosol-generating substrates is positioned within the cavity.

[0184] Ex70. An aerosol-generating article according to Ex69, wherein the aerosol-generating substrate positioned within the cavity comprises tobacco cut filler.

[0185] Ex71. An aerosol-generating article according to Ex69, wherein an aerosol-generating substrate positioned within the cavity is in the form of a plurality of free-flowing beads of aerosolforming material, for example a plurality of discrete free-flowing beads having an average bead diameter of between 0.1 mm and 4 mm, preferably between 1 mm and 2 mm, for example between 1 .2 mm and 1 .7 mm.

[0186] Ex72. An aerosol-generating article according to Ex69, wherein the aerosol-generating material is in the form of shredded aerosol-generating material.

[0187] Ex73. An aerosol-generating article according to Ex72, wherein the shredded aerosolgenerating material comprises one or more of: strips and strands of aerosol-generating material, such as strips and strands of tobacco or homogenised tobacco material

[0188] Ex74. An aerosol-generating article according to any preceding example wherein a thickness of the aerosol-generating article is less than 50 percent of both a length and a width of the aerosol-generating article.

[0189] Ex75. An aerosol-generating article according to any preceding example, wherein an aerosol-generating substrate positioned within the cavity has a mass of between 50 milligrams and 500 milligrams.

[0190] Ex76. An aerosol-generating article according to any preceding example, wherein an aerosol-generating substrate positioned within the cavity has a mass of between 100 milligrams and 350 milligrams, for example between 130 milligrams and 230 milligrams.

[0191] Ex77. An aerosol-generating article for use with an aerosol-generating device to generate an aerosol, for example an aerosol-generating article according to any preceding example, the aerosol-generating article comprising: a first planar external surface; and a second planar external surface, a left side surface and a right side surface, a proximal end surface and a distal end surface, a substrate cavity being located within the article, in which first and second distal corners, defined between the distal end face and the left side face and distal end face and the right side face respectively, are rounded corners.

[0192] Ex78. An aerosol-generating article according to Ex77 in which first and second proximal corners, defined between the proximal end surface and the left side surface and the proximal end surface and the right side surface respectively, are rounded corners.

[0193] Ex79. An aerosol-generating article according to Ex77 and Ex78 in which the first and second distal corners have a smaller radius than the first and second proximal corners.

[0194] Ex80. An aerosol-generating article according to any of Ex77 to Ex79 in which the first and second distal corners have a radius of between 0.5 mm and 2 mm.

[0195] Ex81 . An aerosol-generating article according to any of Ex77 to Ex80 in which the first and second proximal corners have a radius of between 1 mm and 3 mm.

[0196] Ex82. An aerosol-generating article according to any of Ex77 to Ex81 in which the proximal end surface is wider than the distal end surface.

[0197] Ex83. An aerosol-generating article according to any of Ex77 to Ex82 in which air flows into the article through the distal end surface, for example through an inlet defined in the distal end surface, through the substrate cavity, and out of the article through the proximal end surface, for example through an outlet defined through the proximal end surface. Ex83A. An aerosol-generating article according to any preceding example in which the length of the article is greater or equal to the width of the article and the width of the article is at least 2 times the thickness of the article, for example at least 3 times the thickness, for example at least 3.5 times the thickness, or at least 4 times the thickness.

[0198] Ex83B. An aerosol-generating article according to any preceding example in which the length of the article is between 25 mm and 35 mm, for example between 29 mm and 31 mm, for example about 30 mm.

[0199] Ex83C. An aerosol-generating article according to any preceding example in which the width of the article is between 8 mm and 15 mm, for example between 10 mm and 12 mm, for example about 11 mm.

[0200] Ex83D. An aerosol-generating article according to any preceding example in which the thickness of the article is between 2.5 mm and 3.5 mm, for example between 2.9 mm and 3.3 mm, for example about 3.1 mm, or 3.2 mm, or 3.3 mm.

[0201] Ex84. An aerosol-generating system comprising an aerosol-generating article and an aerosol-generating device configured to receive the aerosol-generating article to generate an aerosol, the aerosol-generating article being an article as defined in any preceding example.

[0202] Ex85. An aerosol-generating system comprising an aerosol-generating article and an aerosol-generating device configured to receive the aerosol-generating article to generate an aerosol, for example an aerosol-generating system according to example Ex84, the aerosol-generating article having a length extending in an x-direction between a distal end and a proximal end, a width extending in a y-direction between a left side and a right side, and a thickness extending in a z-direction between an upper side and a lower side, in which the length and the width are greater in magnitude than the thickness, the aerosol-generating device comprising an article receiving cavity for receiving the aerosolgenerating article for use, in which the article is asymmetrically shaped such that a distal end of the article may be operationally engaged with the article receiving cavity whereas a proximal end may not.

[0203] Ex86. An aerosol-generating system according to Ex85, in which the width of a distal portion of the article is smaller than a width of a proximal portion of the article, and the article receiving cavity is dimensioned to receive the article when a distal end of the article is inserted but not when a proximal end of the article is inserted.

[0204] Ex87. An aerosol-generating system according to Ex85 or Ex86, in which an internal shape of the article receiving cavity is configured to mate with an external shape of a proximal portion of the aerosol-generating article when the article is operationally engaged with the article receiving cavity.

[0205] Ex88. An aerosol-generating system according to any of examples Ex85 to Ex87, in which the article is an article as defined in Ex63 having rounded distal corners, in which the aerosol- receiving cavity comprises a distal end having corners rounded to engage with the distal end of the aerosol-generating article.

[0206] Examples will now be further described with reference to the figures in which:

[0207] Figure 1 shows a perspective view of an embodiment of an aerosol-generating article;

[0208] Figure 2 shows an exploded perspective view of the aerosol-generating article of Figure 1 ;

[0209] Figure 3 shows an exploded perspective view of a further embodiment of an aerosol- generating article;

[0210] Figure 4 shows an exploded perspective view of a further embodiment of an aerosolgenerating article;

[0211] Figure 5 shows an exploded perspective view of a further embodiment of an aerosolgenerating article;

[0212] Figure 6 shows an exploded perspective view of a further embodiment of an aerosolgenerating article;

[0213] Figure 7 shows an exploded perspective view of a further embodiment of an aerosol- generating article;;

[0214] Figure 8 shows a perspective view of an aerosol-generating article according to an embodiment of the present disclosure;

[0215] Figure 9 shows an exploded perspective view of the aerosol-generating article of Figure 8;

[0216] Figure 10 shows a cross-sectional plan view of the article of Figure 9, shown in the X-Y plane;

[0217] Figure 11 shows an exploded perspective view of an article according to another embodiment of the present disclosure;

[0218] Figure 12 shows a cross-sectional plan view of the article of Figure 11 , shown in the X-Y plane;

[0219] Figure 13 shows a cross-sectional transverse view of a proximal portion of the article of Figure 11 (taken along line A-A) shown in the Y-Z plane;

[0220] Figure 14 shows a cross-sectional transverse view of a distal portion of the article of Figure 11 (taken along line B-B) shown in the Y-Z plane ;

[0221] Figure 15 shows an exploded perspective view of an article according to another embodiment of the present disclosure;

[0222] Figure 16 shows a cross-sectional plan view of the article of Figure 15, shown in the X-Y plane;

[0223] Figure 17 shows a perspective view of an aerosol-generating article according to another embodiment of the present disclosure;

[0224] Figure 18 shows an exploded perspective view of the aerosol-generating article of Figure 17;

[0225] Figure 19 shows an exploded perspective view of an article according to another embodiment of the present disclosure; Figure 20 shows an exploded perspective view of an article according to another embodiment of the present disclosure;

[0226] Figure 21 shows a schematic cross-sectional side view of an aerosol-generating device used as part of an aerosol-generating system according to the present disclosure;

[0227] Figure 22 shows a schematic cross-sectional side view of the aerosol-generating device of Figure 21 in operational engagement with the aerosol-generating article of figure 8; and

[0228] Figure 23 shows a schematic cross-sectional plan view of the aerosol-generating device of Figure 21 in operational engagement with the aerosol-generating article of figure 8.

[0229] Figures 1 to 7 show embodiments of aerosol-generating articles for use with an aerosolgenerating device to generate an aerosol. Figures 8 to 23 illustrate various embodiments of aerosol-generating articles and aerosol-generating systems, understanding of which is assisted by the description of figures 1 to 7.

[0230] Figure 1 shows an aerosol-generating article 10 comprising a first planar external layer 24 forming a first planar external surface 21 , a second planar external layer 25 forming a second planar external surface 22, and a frame 50 positioned between the first planar external layer 24 and the second planar external layer 25. The first planar external layer 24 and the second planar external layer 25 both comprise an aerosol-generating substrate comprising an aerosol-generating material, namely tobacco. However, it will be understood that in some embodiments only one of the first planar external layer 24 and the second planar external layer 25 may comprise an aerosolgenerating substrate. Alternatively, or additionally, the aerosol-generating substrate may be positioned elsewhere within the aerosol-generating article 10.

[0231] The aerosol-generating article 10 has a length extending in the x-direction, a width extending in the y-direction and a thickness extending in the z-direction. The aerosol-generating article 10 has a length of 30 millimetres, a width of 10 millimetres, and a thickness of 3.1 millimetres.

[0232] The aerosol-generating article 10 is substantially flat aerosol-generating article or substantially planar aerosol-generating article. In particular, the thickness of the aerosol-generating article 10 is less than 50 percent of both the length and the width of the aerosol-generating article. The aerosol-generating article 10 has a generally rectangular cuboid shape and a laminated structure formed by the first planar external layer 24, the frame 50 and the second planar external layer 25. The first planar external layer 24, the frame 50 and the second planar external layer 25 are bonded together with an adhesive, in particular guar gum, as discussed in more detail below in relation to Figure 2.

[0233] Figure 2 shows an exploded view of the aerosol-generating article 10 of Figure 1 .

[0234] The frame 50 has a length of 30 millimetres, a width of 10 millimetres, and a thickness of 2.7 millimetres. The frame 50 is made from cardboard and defines a frame aperture extending through the thickness of the frame 50. The frame aperture at least partially forms a cavity 30. The cavity 30 has length of 26 millimetres, a width of 6 millimetres, and a thickness of 2.7 millimetres. Therefore, the cavity 30 has a volume of about 421.2 cubic millimetres. In this embodiment, the cavity 30 is substantially empty.

[0235] The frame 50 has a frame inner surface 52 extending in the z-direction or the transverse direction between the first planar external surface 21 and the second planar external surface 22. The frame inner surface 52 defines a cavity outer wall. The frame 50 has a frame outer surface 53 extending in the z-direction or the transverse direction between the first planar external surface 21 and the second planar external surface 22. The frame outer surface 53 at least partially defines one or more external surfaces of the aerosol-generating article, such as the front wall 13 and the back wall 14.

[0236] The frame 50 comprises a peripheral wall 51 that circumscribes the cavity 30. In more detail, the peripheral wall 51 is defined by the frame inner surface 52 and the frame outer surface 52. The peripheral wall 51 has a radial thickness, as measured between the frame inner surface 52 and the frame outer surface 53 in the x / y plane, of about 2 millimetres.

[0237] The first planar external layer 24 and the second planar external layer 25 have a thickness of 200 micrometres and are in physical contact with the frame 50. The first planar external layer

[0238] 24 and the second planar external layer 25 are bonded to the frame with an adhesive 15. The first planar external layer 24 defines at least a portion of the cavity 30. The second planar external layer

[0239] 25 defines at least a portion of the cavity 30.

[0240] The aerosol-generating article 10 comprises an air inlet 11 and an air outlet 12. The air inlet 11 and the air outlet 12 are defined by, and extend through, the peripheral wall 51 of the frame 50. The air inlet 11 and the air outlet 12 each have a rectangular cross-section, a width of 2 millimetres, and a thickness of 0.9 millimetres. An airflow passage extends between the air inlet 11 and the air outlet 12 through the cavity 30.

[0241] Figure 3 shows an exploded view of an aerosol-generating article that is similar to the aerosol-generating article 10 of Figure 1 except that the first planar external layer 24 and the second planar external layer 25 do not comprise an aerosol-generating substrate. Instead, an aerosol-generating substrate 40 is positioned within the cavity 30. The aerosol-generating substrate 40 comprises an aerosol-generating material in the form of tobacco cut filler and has an aerosol-former content of 5 percent by weight on a dry weight basis. As shown, the aerosolgenerating substrate 40 fills the entire volume of the cavity 30. In the example of Figure 3, the aerosol-generating substrate 40 has a packing density of about 0.87, a density of about 0.3 grams per cubic centimetre, and a mass of about 110 milligrams. In another example, the aerosolgenerating substrate 40 may have a different packing density, a different density and a different mass. For example, aerosol-generating substrate may have a packing density of 0.64, a density of 0.35 grams per cubic centimetre, and a mass of about 95 milligrams. In another example, the aerosol-generating substrate may be in the form of aerosol-generating beads, for example discrete free flowing beads having an average bead diameter of between 0.1 mm and 4 mm. Figure 4 shows an aerosol-generating article 10 similar to the aerosol-generating article 10 of Figures 1 and 3 except that the aerosol-generating article 10 of Figure 4 comprises an outer wrapper 23 defining the first planar external surface 21 and the second planar external surface 22 instead of the first planar external layer 24 and the second planar external layer 25.

[0242] Figure 5 shows an aerosol-generating article 10 similar to the aerosol-generating article 10 of Figure 1 except that the aerosol-generating article 10 of Figure 5 further comprises a first aerosol-generating substrate layer 41 and a second aerosol-generating substrate layer 42. The first aerosol-generating substrate layer 41 and the second aerosol-generating substrate layer 42 are formed from a sheet of aerosol-generating material. In particular, a sheet of homogenised tobacco material having an aerosol-former content of 5 percent by weight on a dry weight basis. The first aerosol-generating substrate layer 41 and the second aerosol-generating substrate layer 42 each have a length equal to the length of the aerosol-generating article 10, a width equal to the width of the aerosol-generating article 10 and a thickness of 200 micrometres. That is, the aerosolgenerating article 10 has a length of 30 millimetres, a width of 10 millimetres, and a thickness of 3.5 millimetres.

[0243] The first aerosol-generating substrate layer 41 and the second aerosol-generating substrate layer 42 are in physical contact with the frame 50 and are bonded to the frame with an adhesive 15. The first aerosol-generating substrate layer 41 defines at least a portion of the cavity 30. The second aerosol-generating layer 42 defines at least a portion of the cavity 30.

[0244] The first planar external layer 24 is in physical contact with the first aerosol-generating substrate layer 41 and are bonded together with an adhesive 15. The second planar external layer 25 is in physical contact with the second aerosol-generating substrate layer 42 and are bonded together with an adhesive 15.

[0245] Figure 6 shows an exploded view of an aerosol-generating article 10 that is similar to the aerosol-generating article 10 of Figure 5 except that an aerosol-generating substrate 40 is positioned within the cavity 30 as described in relation to Figure 3. The aerosol-generating substrate 40 comprises an aerosol-generating material in the form of tobacco cut filler and has an aerosol-former content of 5 percent by weight on a dry weight basis. As shown, the aerosolgenerating substrate 40 fills the entire volume of the cavity 30.

[0246] Figure 7 shows an aerosol-generating article 10 similar to the aerosol-generating article 10 of Figure 5 except that the aerosol-generating article 10 of Figure 7 comprises an outer wrapper 23 defining the first planar external surface 21 and the second planar external surface 22 instead of the first planar external layer 24 and the second planar external layer 25.

[0247] Figure 8 shows a perspective view of an aerosol-generating article 80 that is similar to the aerosol-generating article of Figure 1 except that the geometries of the first planar external layer 824, second planar external layer 825 and frame 850 of Figure 8 have different geometries to the first planar external layer 24, second planar external layer 25 and frame 50 of Figure 1 . Figure 9 shows an exploded view of the aerosol-generating article 80 of Figure 8. Similar to Figure 1 , the first planar external layer 824 forms a first planar external surface 821 , a second planar external layer 825 forms a second planar external surface 822, and the frame 850 is positioned between the first planar external layer 824 and the second planar external layer 825.

[0248] The aerosol-generating article 80 has a length extending in the x-direction, a width extending in the y-direction and a thickness extending in the z-direction. The aerosol-generating article 80 has a length of 30 millimetres, a maximum width of 11 millimetres, and a thickness of 3.1 millimetres.

[0249] The aerosol-generating article 80 comprises a proximal end face 814, a distal end face 813, a left side face 817 and a right side face 818. The aerosol-generating article 80 has a first proximal corner 847 defined between the left side face 817 and the proximal end face 814; a second proximal corner 848 defined between the right side face 818 and the proximal end face 814; a first distal corner 837 defined between the left side face 817 and the distal end face 813; and a second distal corner 838 defined between the right side face 818 and the distal end face 813. In this embodiment, the first proximal corner 847 and second proximal corner 848 are rounded corners with a radius of 2 millimetres; and the first distal corner 837 and second distal corner 838 are rounded corners with a radius of 1 millimetre. Thus, the first and second distal corners 837, 838 have a smaller radius that the first and second proximal corners 847, 848 and the external shape of the aerosol-generating article 80 is asymmetrical in the x-direction.

[0250] The distance between the left side face 817 and right side face 818 decreases towards the distal end face 813. The distance between the left side face 817 and right side face 818 begins to decrease from two-thirds of the length between the proximal end face 814 and distal end face 813. In other words, the external shape of the aerosol-generating article 80 begins to taper at a distance of 10 millimetres away from the distal end face 813, i.e. along a distal third of the article 80. By having a narrower distal end compared the proximal end, the aerosol-generating article 80 may be configured to only be insertable with the distal end first into an aerosol-generating device.

[0251] The frame 850 has a length of 30 millimetres, a maximum width of 11 millimetres, and a thickness of 2.8 millimetres. Maximum width is the transverse width at the widest point of the article. The frame 850 has substantially the same external profile in the X-Y plane as the first and second external layers 824, 825 in the X-Y plane. The frame 850 defines a frame aperture extending through the thickness of the frame 850. The frame aperture at least partially forms a cavity 830. The cavity 830 has length of 14 millimetres, a maximum width of 8 millimetres, and a thickness of 2.8 millimetres. Maximum width of the cavity is the transverse width of the cavity at its widest point. The cavity 830 comprises a proximal end 833 and a distal end 834. The width of the cavity 830 at the proximal end 833 is 7 millimetres. The width of the cavity 830 at the distal end 834 is 8 millimetres. Thus, the cavity 830 is narrower at a distal end 833 compared to a proximal end 834 of the cavity and the cavity 830 is asymmetrical in the x-direction. The asymmetry of the cavity mirrors the asymmetry of the article. In this embodiment, the four internal corners of the cavity 830 are four rounded corners each having a radius of 1.5 millimetres. In this embodiment, a midpoint 801 of the cavity 830 is located closer to the distal end face 813 than to the proximal end face 814. The midpoint 801 of the cavity is a point in the middle of the cavity with respect to both length and width. Thus, the cavity 830 is asymmetrically positioned within the article 80. The cavity is configured to hold aerosol-generating substrate, for example an aerosol-generating substrate formed from a plurality of discrete beads of aerosol-forming material.

[0252] The frame 850 has a frame inner surface 852 extending in the z-direction or the transverse direction between the first planar external surface 821 and the second planar external surface 822. The frame inner surface 852 defines a cavity wall of the cavity. The frame 850 has a frame outer surface 853 extending in the z-direction or the transverse direction between the first planar external surface 821 and the second planar external surface 822. The frame outer surface 853 at least partially defines one or more external surfaces of the aerosol-generating article, such as the distal end face 813 and the proximal end face 814.

[0253] The first planar external layer 824 and the second planar external layer 825 each have a thickness of 150 micrometres and are in physical contact with the frame 850 in Figure 8. The first planar external layer 824 and the second planar external layer 825 are bonded to the frame with an adhesive (not shown). The first planar external layer 824 defines at least a portion of the cavity 830. The second planar external layer 825 defines at least a portion of the cavity 830. The cavity 830 is located between the first planar external layer 824 and the second planar external layer 825; between the proximal end face 814 and the distal end face 813; and between the left side face 817 and a right side face 818.

[0254] The aerosol-generating article 80 comprises an air inlet 811 and an air outlet 812. The air inlet 811 extends between the distal end face 813 and the distal end 833 of the cavity 830. The air inlet 811 has a length of 3 millimetres. The air outlet 812 extends between the proximal end 834 of the cavity 830 and the proximal end face 814. The air outlet 812 has a length of 12 millimetres. In this embodiment, the air inlet 811 and the air outlet 812 each define a hollow channel with a rectangular cross-section, a width of 4 millimetres, and a thickness of 2 millimetres. An airflow path extends between the air inlet 811 and the air outlet 812 through the cavity 830. Thus, air can enter the article through the air inlet, pass through the cavity containing aerosol-forming substrate, and exit the article through the air outlet. The air outlet is longer than the air inlet.

[0255] The substrate cavity 830 is asymmetrically situated towards a distal end of the article. This allows the entire substrate cavity to be inserted into an aerosol-generating device to be heated, while still allowing enough of the article to project from the device for a user to grip the article for extraction.

[0256] A longer air outlet also allows for greater cooling of the aerosol after exiting the heating zone of the substrate cavity and before entering a user’s mouth. This is because the longer air outlet extends the time for heat to dissipate from the aerosol and provides greater surface area of the air outlet through which the heat can dissipate before entering the user’s mouth.

[0257] The formation of an aerosol by heating an aerosol-forming substrate may result in generation of moisture and slurry. Such moisture and slurry may be drawn towards a user during use of the article. The provision of a relatively long air outlet channel between the substrate cavity and the user may allow for some of this moisture and slurry to be retained by walls of the air outlet and, therefore, not transferred to the user.

[0258] In a specific embodiment, the aerosol-forming substrate is in the form of a plurality of discrete, free-flowing, beads of aerosol-forming material. The beads are substantially spherical beads. The beads have a mean diameter of between 1 mm and 2 mm, preferably about 1 .5 millimetres, and a density of 1 .3 grams per cubic centimetre. The total weight of beads in the substrate cavity is approximately 150 mg. The beads are formed of an aerosol-generating substrate comprising plant particles, aerosol former and a hydrocolloid binder. An example of a suitable composition of the aerosol-generating substrate forming the beads is provided below.

[0259] Examples of bead compositions

[0260] Suitable compositions for forming beads of aerosol-generating substrate according to the invention are set out in Table 1 below:

[0261] All amounts are shown as percentages by weight, on a dry weight basis, based on the total weight of the aerosol-generating element.

[0262] In order to make the beads, the tobacco particles are first mixed with glycerin. The HPMC or CMC binder is dispersed in glycerin and then water is added to form an aqueous binder solution. The binder solution is added to the mixture of tobacco particles and glycerin and all of the components are mixed to form a dough. The dough is extruded to form a plurality of discrete elements and the discrete elements are then spheronized at low speed to form spherical beads having an average diameter of 1 .5 millimetres. The beads are dried in an oven to a desired moisture content. The dried beads can then be incorporated into a variety of different aerosolgenerating articles, as described above.

[0263] When such beads were incorporated into an aerosol-generating article as described herein and heated, an aerosol was generated containing nicotine and glycerin from the aerosolgenerating substrate. The ratio of nicotine to glycerin in each puff of aerosol was found to remain consistent over the duration of the heating. This is in contrast to the aerosol generated from an article having a similar construction but in which the aerosol-generating substrate is in the form of tobacco cast leaf. With the tobacco cast leaf substrate, the aerosol generated under the same conditions was found to have a much more variable ratio of nicotine to glycerin per puff. The provision of an aerosol with a more consistent ratio of nicotine to glycerin across puffs provides an optimal sensory experience to the consumer over the duration of the heating.

[0264] For exemplary purposes applicable to any of the embodiments described herein, a composition of aerosol-forming material that may be used to form the plurality of aerosol-forming beads may be as follows. Percentages are given in weight percent with respect to the product in its final state. The aerosol-forming substrate may have a moisture of about 5 to 25%, preferably of about 7 to 15%, at final product state. The aerosol-forming substrate may further comprise the following:

[0265] 1 . Tobacco leaf; for example, about 15 to 45%, preferably of about 20 to 35% of a blend of tobacco leaf, incorporating at least one of the following tobacco types: bright tobacco; dark tobacco; aromatic tobacco. Tobacco material is ground and graded to a particle size of about 100 to 380 mesh, preferably of about 170 to 320 mesh.

[0266] 2. Cellulose fibres; for example, about 1 to 15%, preferably of about 3 to 7%, of cellulose fibres, of a length of about 10 to 250 pm, preferably of about 10 to 120 pm.

[0267] 3. Tobacco fibres; for example, about 5 to 20%, preferably of about 7 to 15% of tobacco fibres, as filler, of any tobacco type or a blend of tobacco types. Tobacco fibres are preferably derived from stems and / or or stalks, graded to fibres of a length of about 10 to 350 pm, preferably of about 10 to 180 pm.

[0268] 4. Binder; for example, about 1 to 10%, preferably of about 1 to 5%, of a binder such as any of common gums or pectins used in food and beverage (F&B) industries. Preferred binders may be natural pectins, such as fruit, for example citrus, or tobacco pectins; guar gums, land locust bean gums, such as hydroxyethyl and / or hydroxypropyl of those; starches, such as modified or derivatized starches; alginate; methyl, ethyl, ethylhydroxymethyl and carboxymethyl, celluloses; dextran; and xanthan gum. The preferable binder is guar.

[0269] 5. Aerosol-former; for example, about 5 to 35%, preferably of about 10 to 25%, of an aerosol former. Suitable aerosol-formers known in the art include: glycerine; monohydric alcohols like menthol, polyhydric alcohols, such as triethylene glycol; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyls of those.

[0270] “Tobacco type” means one of the different varieties of tobacco, for example based on the distinct curing process that the tobacco undergoes before it is further processed in a tobacco product.

[0271] For exemplary purposes, a composition of a further aerosol-forming substrate, which may also be suitable for use as the aerosol-forming substrate in any of the embodiments described above is described below. Percentages are given in weight percent with respect to the product in its final state. The aerosol-forming substrate may comprise:

[0272] 1 . An aerosol-former such as Glycerin; for example, about 10 to 40 %, preferably of about 20 to 30 %.

[0273] 2. Organic fibres; for example, about 10 to 30 %, preferably of about 15 to 25%, of any botanical variety suitable and with purity to comply with applicable FDA F&B grade requirements, as commonly available in the market. For example, organic fibres may derive from cellulose, cotton, wood, tea botanical varieties as sub-products, and subprocessed waste, of F&B tea industry. Organic fibres are preferably of a length of about 10 to 400 pm, preferably of about 10 to 200 pm.

[0274] 3. Organic botanical glycerite; for example, about 15 to 55 %, preferably of about 20 to 35 %, of botanicals such as Clove, Echinacea sp., Fennel, Ginger, Hawthorn berry, Elderberry, Monarda, Mullein leaves, Nettle, Plantain, Turmeric, Yarrow, and compounds of those.

[0275] 4. Organic botanical extracts; for example about 1 to 15 %, preferably of about 2 to 7 %, of any of the previously referred botanicals, as well as menthol (dl-Menthol, C10H20O, 2- lsopropyl-5-methylcyclohexanol) such as obtained from Chaerophyllum macrospermum, Mesosphaerum sidifolium, or other related botanic varieties, as well as P-menthan-3-ol, as any secondary alcohol as diastereoisomers of 5-methyl-2-(propan-2-yl)cyclohexan- 1 -oL

[0276] Alternatively, such aerosol-forming substrate may also contain botanical essential oils of about 0.5 to 5 %, preferably of about 1 to 3 %, such as of palm, coconut, and wooden-based essential oils.

[0277] A dough formed from any such aerosol-forming material may be extruded to form a plurality of discrete elements, and the discrete elements may then be spheronized at low speed to form substantially spherical beads having an average diameter of between 0.5 millimetres and 4 millimetres. The beads are dried in an oven to a desired moisture content. The dried beads can then be incorporated into a variety of different aerosol-generating articles, as described herein.

[0278] Figure 10 shows a cross-sectional plan view, in the X-Y plane, of the article 80 of Figures 8 and 9, showing the shape of the article in the X-Y plane, as well as the shape of the air inlet 811 , the air outlet 812, and the cavity 830. The midpoint 801 of the cavity is shown. In this embodiment, the air inlet 811 and air outlet 812 have the same width and thickness, but different lengths.

[0279] Figure 11 is an exploded perspective view of an alternative embodiment of an aerosolgenerating article 80A according to the present disclosure. The article is very similar to the article 80 of figure 8, and similar features have similar reference numerals, differentiated from those of figure 8 by the suffix “A”. In Figure 11 , the air inlet 811 A has a rectangular cross-section, a length of 3 millimetres, a width of 2.5 millimetres, and a thickness of 1 millimetre. The air outlet 812A has a rectangular cross-section, a length of 12 millimetres, a width of 4 millimetres, and a thickness of 2 millimetres. Thus, the air inlet 811 A has a smaller transverse cross-section compared the air outlet 812A.

[0280] Figure 12 shows a cross-sectional plan view, in the X-Y plane, of the article 80A of Figure 11 , showing the shape of the article in the X-Y plane, as well as the shape of the air inlet 811 A, the air outlet 812A, and the cavity 830A. The midpoint 801 A of the cavity is shown.

[0281] Figure 13 shows a transverse cross-sectional view of the article 80A of Figures 11 and 12 in the Y-Z plane. The cross-section is taken along the line marked A-A in Figure 12, which is 3 millimetres away from the proximal end face 814.

[0282] Figure 14 shows a transverse cross-sectional view of the article 80A of Figures 11 and 12 in the Y-Z plane. The cross-section is taken along the line marked B-B in Figure 12, which is 3 millimetres away from the distal end face 813.

[0283] It can be seen that the air inlet 811 A, shown in transverse cross-section in figure 14, has a smaller width, smaller thickness, and therefore smaller transverse cross-sectional area, than the air outlet 812A, shown in transverse cross-section in figure 13. Furthermore, the slight tapering towards the distal end of the article results in the transverse cross sectional width of the article 80A taken along line B-B (10 mm) being slightly less than the transverse cross sectional width of the article 80A taken along line A-A (11 mm). By providing asymmetry with a slight taper of the distal portion of the article, the volume of the substrate cavity, located in the distal portion of the article, may not be compromised to a great degree. Thus, the load of aerosol-generating substrate cam be maximised while still providing a one-way insertion of the article into the device. Furthermore, if the width of the article at the distal end is no less than, for example 15% of the width of the article at the proximal end, the ability to manufacture the articles in a cost and material efficient manner may be optimised.

[0284] Figure 15 is an exploded perspective view of an alternative embodiment of an aerosolgenerating article 80B according to the present disclosure. The article 80B is very similar to the article 80 of figure 8, and similar features have similar reference numerals, differentiated from those of figure 8 by the suffix “B”. In Figure 15, the air inlet 811 B has a length of 4 millimetres and the air outlet 812B has a length of 12 millimetres. The air inlet 811 B has a smaller cross-section at the distal end face 813B than at the distal end 833B of the cavity 830B. Similarly, the air outlet 812B has a smaller cross-sectional area at the proximal end face 814B than at the proximal end 834B of the cavity. Specifically, the air inlet 811 B has a width of 2.5 millimetres, and a thickness of 1 millimetre at the distal end face 813B; and a width of 4 millimetres, and a thickness of 2 millimetres at the distal end 833B of the cavity 830B. The air outlet 12 has a width of 3 millimetres, and a thickness of 1.5 millimetres at the proximal end face 814B; and a width of 4 millimetres, and a thickness of 2 millimetres at the proximal end 834B of the cavity 830B. Thus, the air inlet 811 B and air outlet 812B have a different minimum cross-sectional areas and different average cross- sectional areas in the Y-Z plane. The air inlet is shorter than the air outlet. Although air is drawn into the inlet and out of the outlet, there is still potential for leakage of moisture and slurry from the air inlet into the device during use. Thus, a smaller average air inlet cross-sectional area may help prevent unwanted leakage through the air inlet.

[0285] Figure 16 shows a transverse cross-sectional view of the article 80B of Figure 15 showing the shape of the article in the X-Y plane, as well as the shape of the air inlet 811 B, the air outlet 812B, and the cavity 830B. The midpoint 801 B of the cavity is shown.

[0286] In other embodiments, the air inlet may have a larger cross-sectional area at the distal end face than at the distal end of the cavity; and the air outlet may have a larger cross-sectional area at the proximal end face than at the proximal end of the cavity.

[0287] Figures 17 and 18 show a similar aerosol-generating article 90 to the aerosol-generating article 80 of Figures 8 and 9 except that the geometries of the first planar external layer 924, second planar external layer 925 and frame 950 of Figures 17 and 18 have different geometries to the first planar external layer 824, second planar external layer 825 and frame 850 of Figure 1 . Therefore, Figures 15 to 16 will be described with respect to their differences to Figures 8 and 9 only. Figure 18 shows an exploded view of the aerosol-generating article 90 of Figure 17.

[0288] In Figures 17 and 18, the first and second distal corners 937, 938 are rounded corners and the first and second proximal corners 947, 948 are right-angled. Thus, the aerosol-generating article 90 may be easier to insert into an aerosol-generating device with the distal end face 913 going into the device first. Each of the four corners of the cavity 930 are rounded and of equal radius. In this embodiment, the profile of the cavity 930 in the X-Y plane is shaped as a rounded rectangle. The air inlet 911 is shorter than the air outlet 912, but both inlet 911 and outlet 912 have the same transverse cross-sectional area.

[0289] Figure 19 is an exploded perspective view of an alternative embodiment of an aerosolgenerating article 90A according to the present disclosure. The article 90A is very similar to the article 90 of figure 17, and similar features have similar reference numerals, differentiated from those of figure 17 by the suffix “A”. The article 90A of figure 19 has an air inlet 911 A that is shorter than an air outlet 912A. The transverse cross-sectional area of the air inlet 911 A is less than that of the air outlet 912A.

[0290] Figure 20 is an exploded perspective view of an alternative embodiment of an aerosolgenerating article 90B according to the present disclosure. The article 90B is very similar to the article 90 of figure 17, and similar features have similar reference numerals, differentiated from those of figure 17 by the suffix “B”. The article 90B of figure 20 has an air inlet 911 B that is shorter than an air outlet 912B. The air inlet 911 B and air outlet 912B of the article 90B are both tapered channels having a minimum width at the distal and proximal ends of the article respectively. The tapering of the inlet and outlet is substantially as described in relation to the article 80B of figure 15 above.

[0291] Figure 21 shows a schematic cross-sectional view of an aerosol-generating device 900 configured for use with an aerosol-generating article 80 described herein. The aerosol-generating device 900 is an elongate aerosol-generating device extending between a proximal end 91 and a distal end 92. The aerosol-generating device 900 comprises a battery 93, a controller 94, a first heater 95 and a second heater 96 located within a housing 97. The controller 94 controls supply of power from the battery 93 to the first heater 95 and the second heater 96. A cavity 1000 is defined in the device 900, the cavity 1000 having an opening 1010 defined in the proximal end 91 of the device 900. The opening 1010 is rectangular in shape and is dimensioned to accommodate the maximum transverse cross-section of the aerosol-generating article 80. The cavity 1000 comprises an upper planar surface 1020 and a lower planar surface 1030. The first heater 95 is located in the upper planar surface 1020 to heat the first planar external surface 821 of an aerosolgenerating article 80 inserted into the cavity 1000, and the second heater 96 is located in the lower planar surface 1030 to heat the second planar external surface 822 of an aerosol-generating article 80 inserted into the cavity 1000. The first heater 95 extends partially along the upper planar surface 1020. The second heater 96 extends partially along the lower planar surface 1030. The device 900 comprises an air inlet 98 defining an air-flow path configured to allow air to flow into the cavity 1000 from outside the device.

[0292] Figure 22 shows a schematic cross-sectional view of the aerosol-generating device 900 of Figure 21 in engagement with the aerosol-generating article 80 of Figure 8. There is little tolerance between the first planar external surface 821 and the second planar external surface 822 of the aerosol-generating article 80 and the internal surfaces 1020, 1030 of the cavity 1000. Thus, there is a snug fit between the aerosol-generating article 80 and the aerosol-generating device 900. When a consumer has inserted the aerosol-generating article 80 into the cavity 1000, the device can be operated. The first heater 95 heats the first planar external surface 821 of the aerosolgenerating article 80 and the second heater 96 heats the second planar external surface 822 of the aerosol-generating article, and as a result the aerosol-generating substrate in the aerosolgenerating article 80 is heated. Volatile components of the aerosol-generating substrate are evaporated and condense in the cavity 830 of the aerosol-generating article 80 to form an aerosol. The consumer inhales the aerosol by drawing on the end of the aerosol-generating article 80 comprising the air outlet 812. Once the aerosol-generating substrate has been depleted of volatile components, the aerosol-generating article 80 is removed from the cavity 1000 and disposed of.

[0293] Figure 23 shows a schematic cross-sectional plan view of the aerosol-generating device 900 in engagement with an aerosol-generating article 80. The cavity 1000 comprises a left side surface 1040, a right side surface 1050 and a distal surface 1060. The distance between the left side surface 1040 and right side surface 1050 decreases towards the distal surface 1060. In other words, the cavity 1000 tapers towards the distal surface 1060 such that only the distal end of the aerosol-generating article 80 may be inserted first into the cavity 1000.

[0294] The dimensions of a distal end 813 of the article, and the corresponding shape of the article 80 and the device cavity 1000, means that the article 80 can only be operationally engaged with the device 900 when the distal end 813 of the article is inserted into the cavity 1000. This ensures that the air inlet 811 is inserted into the device to engage with airflow channels defined in the device 900. When operationally engaged, it is preferred that a portion of the proximal end of the article 80 protrudes from the cavity 1000, or can be made accessible, in order to allow a user to remove the article from the cavity.

[0295] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about". Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein. In this context, therefore, a number A is understood as A ± 10% of A. Within this context, a number A may be considered to include numerical values that are within general standard error for the measurement of the property that the number A modifies. The number A, in some instances as used in the appended claims, may deviate by the percentages enumerated above provided that the amount by which A deviates does not materially affect the basic and novel characteristic(s) of the claimed invention. Also, all ranges include the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.

Claims

1. An aerosol-generating article for use with an aerosol-generating device for generating an aerosol, wherein the aerosol-generating article has a length extending in the x-axis direction between a distal end and a proximal end, a width extending in the y-axis direction between a left side and a right side, and a thickness extending in the z-axis direction between a top side and a bottom side, wherein the length and width of the article are greater in magnitude than the thickness of the article, wherein the aerosol-generating article comprises: upper surface; lower surface; and a cavity for the substrate located between the upper surface and the lower surface, wherein the first air flow passage extends between the distal end of the article and the cavity, and the second air flow passage extends between the cavity and the proximal end of the article, wherein the length of the second air flow passage is greater than the length of the first air flow passage, and the minimum cross-sectional area of ​​the first air flow passage is less than the minimum cross-sectional area of ​​the second air flow passage, and wherein the first air flow passage has a distal end located at the distal end of the article and a proximal end located at the entrance to the cavity, wherein the cross-sectional area of ​​the proximal end of the first air flow passage is less than the cross-sectional area of ​​the distal end of the first air flow passage, or the cross-sectional area of ​​the proximal end of the first air flow passage is greater than the cross-sectional area of ​​the distal end of the first air flow passage.

2. The aerosol generating article of claim 1, wherein the first air flow passage is an air inlet and the second air flow passage is an air outlet.

3. An aerosol generating article according to claim 1 or 2, wherein the length of the second air flow passage is at least twice the length of the first air flow passage, such as at least three times, or at least four times, or at least five times the length of the first air flow passage.

4. An aerosol generating article according to any of the preceding claims, wherein the length of the first air flow passage is from 1.5 mm to 6 mm, such as from 2 mm to 4 mm.

5. An aerosol generating article according to any of the preceding claims, wherein the length of the second air flow passage is from 10 mm to 20 mm, such as from 11 mm to 16 mm.

6. An aerosol generating article according to any one of the preceding claims, wherein the minimum width of the first air flow passage is from 2 mm to 6 mm, such as from 3 mm to 5 mm, and preferably the minimum width of the first air flow passage is less than the minimum width of the second air flow passage.

7. An aerosol generating article according to any of the preceding claims, wherein the minimum width of the second air flow passage is from 2 mm to 6 mm, such as from 3 mm to 5 mm.

8. An aerosol generating article according to any of the preceding claims, wherein the minimum thickness of the first air flow passage and / or the second air flow passage is from 0.75 mm to 2.5 mm, such as from 1 mm to 2 mm.

9. The aerosol generating article of claim 9, wherein the width of the first air flow passage increases, such as continuously or linearly increases, between the distal end of the first air flow passage and the proximal end of the first air flow passage, or the width of the first air flow passage decreases, such as continuously or linearly decreases, between the distal end of the first air flow passage and the proximal end of the first air flow passage.

10. An aerosol-generating article according to any one of the preceding claims, wherein the second air flow passage has a proximal end located at the proximal end of the article and a distal end located at the outlet of the cavity, wherein the cross-sectional area of ​​the proximal end of the second air flow passage is less than the cross-sectional area of ​​the distal end of the second air flow passage, or the cross-sectional area of ​​the proximal end of the second air flow passage is greater than the cross-sectional area of ​​the distal end of the second air flow passage.

11. The aerosol generating article of claim 10, wherein the width of the second air flow passage increases, such as continuously or linearly increases, between the distal end of the second air flow passage and the proximal end of the second air flow passage, or the width of the second air flow passage decreases, such as continuously or linearly decreases, between the distal end of the second air flow passage and the proximal end of the second air flow passage.

12. An aerosol generating article according to any one of the preceding claims, wherein the length of the article is from 29 mm to 31 mm, for example, approximately 30 mm, the width of the article is from 10 mm to 12 mm, for example, approximately 11 mm, and the thickness of the article is from 2.9 mm to 3.3 mm, for example, approximately 3.1 mm.

13. An aerosol-generating article according to any preceding claim, wherein the aerosol-generating substrate located within the cavity has a mass of from 100 milligrams to 350 milligrams, such as from 130 milligrams to 230 milligrams.

14. An aerosol generating article according to any one of the preceding claims, wherein the aerosol generating substrate located within the cavity has the form of a plurality of granules of aerosol forming material, such as a plurality of individual free flowing granules having an average granule diameter of from 0.1 mm to 4 mm, preferably from 1 mm to 2 mm, such as from 1.2 mm to 1.7 mm.