Aerosol generating article having a multi-compartment liquid storage part

Abstract

The present invention relates to an aerosol-generating article for use with an aerosol-generating device. The article comprises an open-ended, hollow, cylindrical reservoir body including an outer tubular wall and an inner partition wall extending between two opposing inner portions of the outer tubular wall to divide the reservoir body's interior cavity into a first compartment and a second compartment, the first compartment and the second compartment being disposed laterally adjacent to one another along the longitudinal axis of the reservoir body. The article further comprises a first end cap attached to a first end of the reservoir body, the first end cap sealingly closing at least the first compartment at the first end of the reservoir body. The article further comprises a second end cap attached to a second end of the reservoir body, the second end cap sealingly closing the first and second compartments at the second end of the reservoir body. The second end cap includes a fluid passageway providing fluid communication between the first and second compartments. The present disclosure also relates to an aerosol-generating system comprising such an article and an aerosol-generating device for use with the article. The present disclosure further relates to a method for manufacturing such an article.

Description

Technical Field

[0001] The present disclosure relates to an aerosol article for use with an aerosol generating device, the aerosol article comprising a liquid reservoir for storing an aerosol-forming liquid. The present disclosure also relates to an aerosol generating system comprising such an article and an aerosol generating device for use with the article. The present disclosure further relates to a method of manufacturing such an article.

Background Art

[0002] Generating an inhalable aerosol by heating an aerosol-forming liquid is generally known from the prior art. For this purpose, a liquid aerosol-forming substrate may be conveyed from a liquid reservoir to a region external to the reservoir by a liquid conduit, for example a wick element. The liquid may then be vaporized by a heater and subsequently exposed to an air path so as to form an inhalable aerosol. Both the liquid reservoir and the liquid conduit may be part of an aerosol article configured to be inserted into an aerosol generating device to vaporize the aerosol-forming liquid stored within the article. For various purposes, for example to store a plurality of aerosol-forming liquids in the article or to provide several parts each having a specific function, the liquid reservoir may be divided into several compartments. There are various configurations of such multi-compartment aerosol articles. However, many of these configurations are complex and therefore time-consuming to manufacture.

[0003] Therefore, it is desirable to have an aerosol article with a multi-compartment liquid reservoir that has the advantages of prior art solutions while reducing their limitations. In particular, it is desirable to have an aerosol article with a multi-compartment liquid reservoir that is easy and inexpensive to manufacture.

Summary of the Invention

[0004] According to the present invention, there is provided an aerosol article for use with an aerosol generating device. The article comprises an open-ended tubular, particularly hollow cylindrical, storage body having an outer tubular wall and an inner partition wall extending between two opposing inner portions of the outer tubular wall so as to divide the inner void of the storage body into a first compartment and a second compartment. The first and second compartments are arranged adjacent to each other laterally along the longitudinal axis of the storage body. Further, the article comprises a first end cap attached to the first end of the storage body, the first end cap closing so as to seal the first compartment at least at the first end of the storage body. The article further comprises a second end cap attached to the second end of the storage body, the second end cap closing so as to seal the first and second compartments at the second end of the storage body. The second end cap includes a fluid passage providing fluid communication between the first and second compartments.

[0005] According to the present invention, it has been found that a method of manufacturing an article can be facilitated by assembling the article from individual parts that are easy and inexpensive to manufacture when manufactured separately. In that sense, the article can be easily manufactured by separately manufacturing an open-ended hollow cylindrical storage part body, a first end cap, and a second end cap, and then attaching the first end cap to the first end of the storage part body and the second end cap to the second end of the storage part body. That is, the storage part body, the first end cap, and the second end cap are separate parts, in particular, non-integral parts, i.e., not integrally formed with each other. In particular, the storage part body, the first end cap, and the second end cap are separated from each other before attaching the first end cap to the first end of the storage part body and the second end cap to the second end of the storage part body. Further, even after attaching the first end cap to the first end of the storage part body and the second end cap to the second end of the storage part body, the storage part body, the first end cap, and the second end cap are still separate (non-integral) parts, in particular, not integrally formed with each other. Also, the fact that the storage part body is open-ended and hollow cylindrical simplifies the manufacturing. That is, at least the outer tubular wall has a cylindrical shape and thus has a fixed cross-sectional shape along its longitudinal axis, i.e., along the longitudinal axis (cylindrical axis) of the storage part body. For this reason, at least the outer tubular wall of the storage part body can be manufactured by extrusion. Thereafter, an inner partition wall can be attached between two opposing inner portions of the outer tubular wall so as to divide the inner void of the storage part body into a first compartment and a second compartment. Thus, the storage part body is at least partially an extruded body. In this configuration, the outer tubular wall and the partition wall may be attached to each other by adhesive bonding, for example, welding or adhesion. Advantageously, the adhesive bonding provides a seal between the first compartment and the second compartment and causes the partition wall and the outer tubular wall to become integral.

[0006] The partition wall is preferably parallel to the longitudinal axis of the storage part main body. That is, the cross-sectional profiles of the outer tubular wall and the inner partition wall are constant along the longitudinal axis of the storage part main body. As a result, the storage part main body as a whole has a constant cross-sectional profile along its longitudinal axis. Advantageously, this enables the storage part main body to be manufactured by extrusion. Thus, the storage part main body can be an extruded body as a whole. In particular, the outer tubular wall and the inner partition wall may be integrally formed with each other. Thus, the storage part main body can be extruded in one piece as a whole. That is, the storage part main body may be an integrally extruded body. The integrally extruded storage part main body is particularly easy and inexpensive to manufacture. Furthermore, the integrally extruded storage part main body does not require sealing between the first compartment and the second compartment, and the partition wall and the outer tubular wall are integrated.

[0007] As another method, the outer tubular wall and the inner partition wall may be manufactured as separate parts by extrusion. Thereafter, the extruded inner partition wall can be attached between two opposing inner portions of the extruded outer tubular wall so as to divide the inner void of the storage part main body into the first compartment and the second compartment. Preferably, as already described above, the outer tubular wall and the partition wall may be attached to each other by adhesive bonding, for example, welding or adhesion.

[0008] The main advantages of extrusion over other manufacturing processes are the ability to create complex cross-sections and the ability to function with brittle materials because they are only subjected to compressive and shear stresses during the extrusion press. Extrusion also forms parts with a good surface finish.

[0009] Generally, extrusion molding can be continuous or semi - continuous. Semi - continuous extrusion molding allows for the direct production of many individual parts. In contrast, continuous extrusion molding enables the production of a continuous profile, which can then be separated into individual units, for example, by cutting. Thus, regardless of whether only a part of the storage unit body is an extruded body or the entire storage unit body is an extruded body, the storage unit body can be manufactured by either continuous extrusion molding or semi - continuous extrusion molding.

[0010] Also, it is possible to manufacture at least one of the storage unit body, in particular, at least one of the outer tubular wall and the inner partition by injection molding. Similarly, at least one of the first end cap and the second end cap may be manufactured by injection molding. Depending on their shape, it is also possible to manufacture at least one of the first end cap and the second end cap by extrusion molding.

[0011] The outer tubular wall, and thus the storage unit body, may have any outer cross - sectional shape. The outer cross - sectional shape refers to the shape of the contour of the outer tubular wall and the storage unit body as seen in a cross - sectional view through the outer tubular wall and the storage unit body, which is perpendicular to the longitudinal axis of the storage unit body. Thus, the storage unit body, in particular the outer tubular wall, may have a circular, elliptical, oval, triangular, rectangular, square, hexagonal, or polygonal outer cross - sectional shape.

[0012] The arrangement of the inner partition wall within the outer tubular wall may be asymmetric with respect to a cross - section of the storage unit body that is perpendicular to the longitudinal axis of the storage unit body. This configuration can be used to achieve a first compartment and a second compartment having different volumes. That is, the first compartment may have a volume that is different from, in particular, larger or smaller than, the volume of the second compartment.

[0013] Different volumes of a first compartment and a second compartment can be used to store different amounts of aerosol formation within the article. For example, the first compartment may have a volume smaller than the volume of the second compartment. In this configuration, the first compartment may be used as a main reservoir, and the second compartment may be used at least partially as a buffer reservoir. The details of this configuration will be described in more detail below.

[0014] The asymmetric arrangement of the partition wall is also particularly advantageous when one of the first compartment or the second compartment functions at least partially as a vaporization zone and the aerosol-forming liquid can be vaporized by inductive heating using a susceptor within the vaporization zone. Thus, the article may comprise a vaporization zone including a susceptor disposed off-center with respect to the geometric central axis of the aerosol-generating article. For this purpose, the vaporization zone and the susceptor may be disposed off-center with respect to the axis of symmetry of the alternating magnetic field generated by an inductive heating aerosol-generating device into which the aerosol-generating article can be inserted to heat the aerosol-forming liquid within the vaporization zone. Advantageously, due to the off-center arrangement, the vaporization zone and the susceptor are disposed within a region of the alternating magnetic field having a higher magnetic field density compared to a centrally symmetric arrangement. As a result, the heating efficiency is enhanced.

[0015] The length extension of the inner partition wall in a direction parallel to the longitudinal axis of the reservoir body may be equal to the length extension of the outer tubular wall. Advantageously, this configuration is particularly easy and inexpensive to manufacture, especially by extrusion.

[0016] Similarly, the length extension of the inner partition wall in a direction parallel to the longitudinal axis of the reservoir body may be shorter than the length extension of the outer tubular wall. That is, the inner partition wall may be recessed with respect to the outer tubular wall along its length extension. The recessed inner partition wall can advantageously provide direct fluid communication between the first compartment and the second compartment.

[0017] The first end cap may include an outlet that provides fluid communication between the second compartment and the exterior of the article. The outlet may function as an outlet for the aerosol-forming liquid stored within the article. Similarly, the outlet may function as an outlet through which aerosol generated from the aerosol-forming liquid stored internally within the aerosol-generating article is discharged from the article, in particular, drawn out of the article.

[0018] Particularly in the latter case, the aerosol-generating article may further comprise a filter disposed within or attached to the outlet. The filter may be used to filter out undesirable components of the aerosol. The filter may also include additional materials (such as flavoring materials added to the aerosol).

[0019] Aerosol generation further comprises a mouthpiece. As used herein, the term "mouthpiece" means that part of the article that is positioned in the user's mouth for directly inhaling the aerosol from the article. The mouthpiece may be a separate component attached to other parts of the article, particularly the first end cap. In this configuration, the outlet of the first end cap may open into the mouthpiece, and the mouthpiece may include another outlet through which the aerosol can be discharged from the article into the environment of the article. Alternatively, the first may be formed as a mouthpiece. In this configuration, the outlet of the first end cap opens into the environment of the article and may allow discharge therethrough. When present, the mouthpiece preferably includes a filter. The filler may be the filter described above disposed within or attached to the outlet of the first end cap.

[0020] The storage unit body can be made of any suitable material. The material of the storage unit body is preferably at least one of electrically insulating and non-magnetic. For example, the storage unit body can include or be made of one of PP (polypropylene), PE (polyethylene), or PET (polyethylene terephthalate). PP, PE, and PET are particularly cost-effective and are easy to mold, especially by extrusion molding. The storage unit body may also include or be made of PEEK (polyetheretherketone), which is a heat-resistant material. Furthermore, the material of the storage unit body can have a thermal conductivity, particularly, less than 0.05 watts per meter per kelvin (W·m -1 ·K -1 ). This prevents the user from burning when the aerosol-forming liquid in the article is heated. The storage unit body is preferably made of plastic, particularly heat-resistant plastic. At least one of the first end cap and the second end cap may be made of silicon, PP (polypropylene), PET (polyethylene terephthalate), or PE (polyethylene). By using silicon, closing the first and second compartments to seal them respectively can be promoted.

[0021] The first end cap may be attached to the storage unit body by at least one of form fitting, force fitting, or adhesive bonding. Similarly, the second end cap may be attached to the storage unit body by at least one of form fitting, force fitting, or adhesive bonding. Regarding adhesive bonding, at least one of the first end cap and the second end cap can be attached to the storage unit body by an adhesive or welding, particularly laser welding or ultrasonic welding. As an example of force fitting, at least one of the first end cap and the second end cap may be clamped to the storage unit body. As an example of form fitting, at least one of the first end cap and the second end cap may be attached to the storage unit body by a snap-in connection.

[0022] The fluid passage of the second end cap may include a recess or channel formed within the second end cap to provide fluid communication between the first and second compartments. At least a portion of the fluid passage of the second end cap may be used to form a capillary buffer reservoir.

[0023] Advantageously, the fluid communication between the first and second compartments may be used such that the first and second compartments each have a specific function and cooperate with each other, which will be described in more detail below.

[0024] In this regard, the first compartment or at least a portion thereof may be used as a main reservoir for storing the aerosol-forming liquid. At least a portion of the second compartment may be used as a capillary buffer reservoir in fluid communication with the main reservoir realized by the first compartment or a portion thereof. The capillary buffer is configured to store the aerosol-forming liquid due to capillary action to reliably provide a sufficient amount of the aerosol-forming liquid to a liquid conduit in fluid communication with the buffer reservoir, independent of the article position. For this purpose, the volume of the buffer reservoir is selected such that the capillary effect is dominant over gravity. As a result, after being filled within the buffer reservoir, the aerosol-forming liquid is prevented from flowing back into the main reservoir, especially when the orientation of the article changes, for example, from a substantially upright position to a substantially horizontal position and even to an upside-down position. Basically, the capillary buffer reservoir acts in the same manner as the buffer reservoir of a fountain pen.

[0025] In order to have a capillary phenomenon that is dominant over gravity, at least one dimension of the second compartment can be selected to be on the order of the effective length of the capillary of the aerosol-forming liquid stored in the buffer storage part. Typically, the effective length of the capillary is in the range of a few millimeters for most liquids. Thus, the maximum dimension of the second compartment between two opposing portions of the partition wall and the outer tubular wall can be in the range of 0.2 mm to 5 mm, particularly 0.5 mm to 3 mm, preferably 1 mm to 2.5 mm. These values enable providing a sufficiently large buffer volume for storing a sufficient amount of aerosol-forming liquid while ensuring sufficient capillary action.

[0026] The capillary buffer storage part may have a total volume of up to 60 cubic millimeters, particularly up to 50 cubic millimeters, preferably up to 40 cubic millimeters, more preferably up to 30 cubic millimeters, and most preferably up to 20 cubic millimeters. These volumes still ensure appropriate capillary action.

[0027] Conversely, the total volume of the capillary buffer storage part may be at least 5 cubic millimeters, particularly at least 10 cubic millimeters, preferably at least 15 cubic millimeters. These volumes are still large enough to confine a sufficient amount of aerosol-forming liquid to last for at least several smoking sessions and provide it within the capillary buffer storage part.

[0028] As will be further explained below, the volume of the first compartment may be different from the volume of the second compartment. It is preferred that the volume of the first compartment is larger than the volume of the second compartment. This configuration advantageously allows the first compartment to be used as the main buffer and a part of the second compartment to be used as the capillary buffer storage part. The volume of the second compartment may be at most 50 percent, particularly at most 40 percent, preferably at most 30 percent, more preferably at most 20 percent of the volume of the first compartment.

[0029] Furthermore, as described above, the buffer storage part may be only a part of the second compartment. The other parts of the second compartment can be used as the vaporization zone. The vaporization zone can be a zone where the aerosol-forming liquid being conveyed is vaporized when the article is used with the aerosol generating device. Thus, the aerosol-generating article can comprise a vaporization zone, particularly a vaporization cavity for vaporizing the aerosol-forming liquid. The vaporization zone and the buffer storage part are preferably separated from each other. Thus, the aerosol-generating article may comprise a bushing disposed within the second compartment in a transverse direction, particularly a direction perpendicular to the longitudinal axis of the storage part body, and the bushing divides the second compartment into a vaporization zone and a buffer storage part.

[0030] The entire second compartment may be used as the vaporization zone. In this configuration, the capillary buffer storage part can be formed, for example, by a part of the fluid passage within the second end cap that provides at least fluid communication between the first compartment and the second compartment.

[0031] The aerosol-generating article may further comprise a liquid conduit for conveying the aerosol-forming liquid from the buffer storage part to the vaporization zone. The liquid conduit preferably passes through the bushing. The liquid conduit may pass through the vaporization zone. Alternatively, the liquid conduit may face the vaporization zone. Similarly, the liquid conduit may pass through the buffer storage part. Alternatively, the liquid conduit may face the buffer storage part. As used herein, the term "facing the buffer storage part / vaporization zone" refers to a configuration where the liquid conduit is in fluid communication with the buffer storage part and the vaporization zone respectively, but does not pass through the buffer storage part and the vaporization zone.

[0032] With respect to the flow of liquid through the article, the capillary buffer storage part is preferably downstream of the main storage part. Similarly, the liquid conduit is preferably downstream of the capillary buffer storage part with respect to the flow of liquid through the article.

[0033] Furthermore, with respect to the flow of liquid through the article, at least a portion of the fluid conduit is disposed downstream of, or within, the downstream portion of the capillary buffer reservoir. Advantageously, this disposition ensures that the liquid conduit is properly immersed in the aerosol-forming liquid confined within the capillary buffer reservoir. This in turn ensures proper delivery of the aerosol-forming liquid from the buffer reservoir to the main reservoir and regions external to the buffer reservoir where the aerosol-forming liquid can be vaporized.

[0034] Generally, the liquid conduit can have any shape and configuration suitable for conveying the aerosol-forming liquid from the capillary buffer reservoir to the vaporization zone. In particular, the liquid conduit may include a core element. The configuration of the core element can be a stranded wire having sufficient porosity, a rope of stranded material, a mesh, a mesh tube, several concentric mesh tubes, a cloth, a sheet of material, or a foam (or other porous solid), a roll of fine metal mesh, or a metal foil, some other arrangement of fibers or mesh, or any other shape suitably sized and configured to perform the wicking action described herein.

[0035] The liquid conduit, particularly the core element, can include a bundle of filaments including a plurality of filaments. The bundle of filaments is preferably a bundle of non-stranded filaments. In a bundle of non-stranded filaments, the filaments of the bundle extend adjacent to each other along an extension of the entire length of the bundle of filaments without intersecting each other. Similarly, the bundle of filaments can include a stranded portion where the filaments of the bundle are stranded. The stranded portion can enhance the mechanical stability of the bundle of filaments.

[0036] As an example, the bundle of filaments may include a parallel bundle portion along at least a part of the length extension thereof, where a plurality of filaments may be arranged parallel to each other. The parallel bundle portion may be arranged at one end portion of the bundle of filaments or between both end portions of the bundle of filaments. Alternatively, the parallel bundle portion may extend along the entire length dimension of the bundle of filaments.

[0037] As another example, the bundle of filaments may include a first immersion section, a second immersion section, and an intermediate section between the first immersion section and the second immersion section. Along at least the intermediate section, a plurality of filaments may be arranged parallel to each other. With respect to a particular configuration of an article having a storage portion and a vaporization zone, each of the first immersion section and the second immersion section may be at least partially arranged within the storage portion, and the intermediate section may be arranged within the vaporization zone. This applies at least to the open configuration of the sealing element.

[0038] Since the filaments essentially provide capillary action, it is particularly advantageous to use the filaments for transporting a liquid. Further, in the bundle of filaments, the capillary action is further enhanced due to the narrow spaces formed between the plurality of filaments when bundled. In particular, this applies to the parallel arrangement of filaments where the capillary action is constant along it because the narrow spaces between the filaments do not change along the parallel arrangement.

[0039] The filament is preferably a solid material filament. The solid material filament is inexpensive and easy to manufacture. Furthermore, the solid material filament provides good mechanical stability and thus strengthens the bundle of filaments. Generally, the filament may have any cross-sectional shape suitable for transporting the aerosol-forming liquid, especially when bundled. Thus, the filament may have a circular, oval, oblong, triangular, rectangular, square, hexagonal, or polygonal cross-section. The filament preferably has a substantially circular, oblong, or oval cross-section. Having such cross-sections, the filaments are only in line contact with each other rather than in area contact, forming capillary spaces on themselves between the plurality of filaments.

[0040] Capillarity depends on the reduction of the surface energy of the liquid surface and the solid surface of the filament, which are two separate surfaces in the general droplet. Capillarity includes effects that depend on the radius of curvature of both the liquid surface and the filament. Thus, there is a need for a large surface area and a small radius of curvature, both of which are achieved by the small diameter of the filament. Thus, the plurality of first filaments may have a diameter of up to 0.025 millimeters, up to 0.05 millimeters, up to 0.1 millimeters, up to 0.15 millimeters, up to 0.2 millimeters, up to 0.25 millimeters, up to 0.3 millimeters, up to 0.35 millimeters, up to 0.4 millimeters, up to 0.45 millimeters, or up to 0.5 millimeters.

[0041] Generally, the bundle of filaments may be a bundle of linear filaments, i.e., a bundle of substantially straight, non-curved or non-buckled filaments. This configuration does not exclude slight bending of the bundle of filaments, i.e., a large radius of curvature along the length extension of the bundle of filaments. As used herein, a large radius of curvature may include a radius of curvature that is 10 times, particularly 20 times, or 50 times, or particularly 100 times larger than the total length of the bundle of filaments. Alternatively, the bundle of filaments may be curved. In particular, the bundle of filaments may be substantially U-shaped, or C-shaped, or V-shaped.

[0042] The plurality of filaments may be surface-treated. In particular, the plurality of filaments may include at least a partial surface coating, such as an aerosolized enhanced surface coating, a liquid adhesion surface coating, a liquid repellent surface coating, or an antibacterial surface coating. The aerosolized enhanced surface coating may advantageously enhance the experience of various users in particular. The liquid adhesive surface coating may be beneficial with respect to enhancing the capillary action of the bundle of filaments. The antibacterial surface coating may function to reduce bacterial contamination. In particular, the liquid repellent surface coating at the tip of the filament may avoid liquid dripping.

[0043] Depending on the available space, the dimensions of the filaments, and the amount of aerosol-forming liquid to be conveyed and heated, the bundle of filaments may include 3 to 100 filaments, particularly 10 to 80 filaments, preferably 20 to 60 filaments, more preferably 30 to 50 filaments, for example 40 filaments.

[0044] As yet another example, the liquid conduit may include two filament arrays that partially cross each other. In particular, the liquid conduit may include an array of longitudinal filaments arranged side by side, as well as an array of transverse filaments arranged side by side and crossing the array of longitudinal filaments in a transverse direction with respect to the length extension of the longitudinal filaments. The array of transverse filaments may extend only along a length portion of the array of longitudinal filaments such that the liquid conduit includes at least one grid portion and at least one non-grid portion. As an example, the array of longitudinal filaments may have a substantially cylindrical shape, particularly a hollow cylindrical shape. As another example, the array of longitudinal filaments may have a substantially conical shape or a substantially frustoconical shape, particularly a substantially hollow conical shape or a substantially hollow frustoconical shape. In any of these configurations, the longitudinal filaments respectively form a cylindrical, conical, frustoconical, hollow cylindrical, hollow conical, or hollow frustoconical shell surface. The longitudinal axis of each shape extends substantially along the length extension of the longitudinal filaments. Advantageously, any of the aforementioned shapes provides inherent mechanical dimensional stability. The array of transverse filaments preferably has a substantially ring shape in any of these configurations. That is, the transverse filaments extend along the outer periphery of the array of cylindrical, conical, frustoconical, hollow cylindrical, hollow conical, or hollow frustoconical shapes of the longitudinal filaments in the grid portion of the susceptor assembly. Overall, the susceptor assembly has a substantially crown shape in any of the aforementioned configurations. Further, in the case of a conical, frustoconical, hollow conical, or hollow frustoconical shape, the longitudinal filaments branch away from each other towards the base of each shape. Accordingly, an array of longitudinal filaments of a conical, frustoconical, hollow conical, or hollow conical shape facilitates the provision of a fan-out portion.

[0045] The liquid conduit is preferably capable of being inductively heated. Thus, the liquid conduit advantageously has the ability to perform both the functions of transporting and heating the aerosol-forming liquid. Advantageously, this dual function saves a great deal of the liquid conduit material and allows for a compact design without having separate means for transport and heating. Further, there is direct thermal contact between the heat source, i.e., the liquid conduit and the aerosol-forming liquid adhered thereto. Unlike the case where the heater contacts a saturated wick, the direct contact between the liquid conduit and a small amount of liquid advantageously allows for flash heating, i.e., a rapid onset of evaporation. In this regard, the liquid conduit can be considered to be or to include a liquid transport susceptor assembly. As used herein, the term "inductively heatable" refers to a liquid conduit that includes a susceptor material having the ability to convert electromagnetic energy into heat when subjected to an alternating magnetic field. This can be the result of at least one of hysteresis losses or eddy currents induced within the susceptor material depending on its electrical and magnetic properties. Hysteresis losses occur in ferromagnetic or ferrimagnetic susceptor materials due to magnetic domains within the material that are switched under the influence of an alternating electromagnetic field. Eddy currents are induced within a conductive susceptor material. In the case of a conductive ferromagnetic or ferrimagnetic susceptor material, heat is generated by both eddy currents and hysteresis losses.

[0046] Accordingly, an inductively heatable liquid conduit can include at least a first susceptor material. The first susceptor material may each include or be made of a material that is at least one of conductive and ferromagnetic or ferrimagnetic. That is, the first susceptor material can include or be made of one of a ferrimagnetic material, a ferromagnetic material, a conductive material, or a conductive ferrimagnetic material or a conductive ferromagnetic material.

[0047] Furthermore, the liquid conduit may include a second susceptor material. The first susceptor material may be optimized for heat loss and thus heating efficiency, and the second susceptor material may be used as a temperature marker. For this reason, the second susceptor material preferably includes one of a ferromagnetic material or a ferrimagnetic material. In particular, the second susceptor material may be selected to have a Curie temperature corresponding to a predetermined heating temperature. At that Curie temperature, the magnetism of the second susceptor material changes from ferromagnetic or ferrimagnetic to paramagnetic, accompanied by a temporary change in its electrical resistance. Therefore, by monitoring the corresponding change in the current absorbed by the induction source, the change can be detected when the second susceptor material reaches its Curie temperature and thus when the predetermined heating temperature is reached. The first susceptor material is preferably different from the second susceptor material. The second susceptor material preferably has a Curie temperature lower than 500 degrees Celsius. In particular, the second susceptor material may have a Curie temperature below 350 degrees Celsius, preferably below 300 degrees Celsius, more preferably below 250 degrees Celsius, even more preferably below 200 degrees Celsius, and most preferably below 150 degrees Celsius. The Curie temperature is preferably selected to be below the boiling point of the aerosol-forming liquid that is vaporized in order to prevent the generation of harmful components in the aerosol.

[0048] As an example, the liquid conduit may include a plurality of first filaments that contain or are made of a first susceptor material. Additionally, the liquid conduit may include a plurality of second filaments that contain or are made of a second susceptor material. Only a few filaments are necessary to function sufficiently as a temperature marker. Thus, the number of first filaments may be greater than the number of second filaments, particularly, two times, or three times, or four times, or five times, or six times, or seven times, or eight times, or nine times, or ten times greater. Preferably, the diameters of the first and second filaments are greater than twice the skin depth in order to induce a sufficient amount of eddy current and thus generate a sufficient amount of thermal energy when exposed to an alternating magnetic field. The skin depth is a measure of how far electrical conduction occurs within a conductive susceptor material when inductively heated. Thus, depending on the material and frequency of the alternating magnetic field used, the first and second filaments may have a diameter of at least 0.015 millimeters, at least 0.02 millimeters, at least 0.025 millimeters, at least 0.05 millimeters, at least 0.075 millimeters, at least 0.1 millimeters, at least 0.125 millimeters, at least 0.15 millimeters, at least 0.2 millimeters, at least 0.3 millimeters, or at least 0.4 millimeters. The second filaments may be randomly distributed throughout the liquid conduit. Advantageously, the random distribution requires only minimal effort during the manufacture of the liquid conduit.

[0049] The plurality of first filaments and optional plurality of second filaments described above may be used in any of the configurations of the liquid conduits described above, for example, a bundle of filaments including at least one parallel bundle portion, a bundle of filaments including two immersion sections and an intermediate portion, or a liquid conduit including two filament arrays that partially cross each other to form at least one grid portion and at least one non-grid portion.

[0050] When the liquid conduit is inductively heatable, the filament may, as already described above, be disposed off-center with respect to the geometric central axis of the aerosol-generating article. For this reason, the liquid conduit may be disposed off-center with respect to the axis of symmetry of the alternating magnetic field generated by an inductive heating aerosol-generating device into which the aerosol-generating article can be inserted to heat the liquid conduit. Advantageously, due to the off-center, i.e., asymmetric, arrangement, the liquid conduit is disposed within a region of the alternating magnetic field having a higher magnetic field density as compared to a symmetric central arrangement. As a result, the heating efficiency is enhanced.

[0051] The aerosol-generating article may be an aerosol-generating article for single use or an aerosol-generating article for multiple uses. In the latter case, the aerosol-generating article may be refillable. That is, the main reservoir may be refillable with the aerosol-forming liquid. In any configuration, the aerosol-generating article may further comprise an aerosol-forming liquid contained within at least a first compartment. The aerosol-forming liquid may also be contained within at least a portion of a second compartment.

[0052] As used herein, the term "aerosol-forming liquid" relates to a liquid having the ability to release volatile compounds that can form an aerosol upon heating of the aerosol-forming liquid. The aerosol-forming liquid is intended to be heated. The aerosol-forming liquid may include both solid aerosol-forming materials or components and liquid aerosol-forming materials or components. The aerosol-forming liquid may include a tobacco-containing material that includes volatile tobacco flavor compounds released from the liquid upon heating. Alternatively or additionally, the aerosol-forming liquid may include non-tobacco materials. The aerosol-forming liquid may further include an aerosol former. Examples of suitable aerosol formers are glycerin and propylene glycol. The aerosol-forming liquid may also include other additives and components such as nicotine or flavorants. In particular, the aerosol-forming liquid may include water, solvents, ethanol, plant extracts, and natural or artificial flavors. The aerosol-forming liquid may be an aqueous aerosol-forming liquid or an oily aerosol-forming liquid.

[0053] To facilitate fluid flow around the end of the partition wall facing the bottom end cap, the end face of the partition wall at the second end of the reservoir body may be rounded and, in particular, may include a rounded edge. In particular, the rounded edge facilitates the infiltration of air into the reservoir so that it flows around the end of the partition. In contrast, a sharp edge can act as a bubble trap due to the pinning of the contact line.

[0054] According to the present invention, there is also provided an aerosol generation system comprising an aerosol generation device and an aerosol article according to the present invention and as described herein. The article is configured for use with the aerosol generation device.

[0055] As used herein, the term "aerosol generating device" is used to describe an electrically operated device having the ability to interact with at least one aerosol generating article containing at least one aerosol forming liquid so as to generate an aerosol by heating the aerosol forming liquid within the article. The aerosol generating device is preferably a smoking device for generating an aerosol that can be directly inhaled by the user through the user's mouth. In particular, the aerosol generating device is a handheld aerosol generating device.

[0056] The device may comprise a receiving cavity for removably receiving at least a portion of the aerosol generating article.

[0057] Furthermore, the aerosol generating device may comprise an electrical heating arrangement. The heating arrangement may be configured to heat the aerosol forming liquid contained within the article. In particular, the heating arrangement may be configured to heat the aerosol forming liquid conveyed by the liquid conduit from the storage part to a region external to the buffer storage part, particularly to the vaporization zone as described above.

[0058] The heating arrangement may be a resistive heating arrangement including a resistive heating element for heating the aerosol forming liquid. The resistive heating element may be, for example, a heating wire or a heating coil. In use, the resistive heating element is disposed in thermal contact with, or in close thermal proximity to, the aerosol forming liquid to be heated. In particular, the resistive heating element may be disposed in thermal contact with, or in close thermal proximity to, a part of the liquid conduit, particularly a part of the liquid conduit disposed within the vaporization zone of the aerosol generating article, when the aerosol generating article is received within the aerosol generating device.

[0059] Alternatively, the heating arrangement may be an induction heating arrangement. That is, the aerosol generator may be an induction heating aerosol generator. This configuration is particularly preferred when the liquid conduit of the article is induction heatable. Induction heating can also function when the aerosol generating article comprises a liquid conduit disposed in the vaporization zone of the aerosol generating article, in particular a (separate) susceptor element thermally contacting or thermally proximate to a portion of the liquid conduit. Also, the aerosol generator itself may comprise a susceptor element that thermally contacts or is thermally proximate to a portion of the liquid conduit, in particular a portion of the liquid conduit disposed within the vaporization zone of the aerosol generating article, when the aerosol generating article is received within the aerosol generator. In the latter configuration, i.e., when the liquid conduit itself is not induction heatable, the susceptor element may be, for example, a susceptor sleeve or susceptor coil surrounding the liquid conduit, in particular a portion of the liquid conduit disposed in the vaporization zone of the aerosol generating article.

[0060] An induction heating aerosol generator, in particular an induction heating arrangement, may include at least one induction source configured and arranged to generate an alternating magnetic field within a receiving cavity for inductively heating an aerosol-forming liquid within the aerosol generating article when the article is received within the aerosol generator.

[0061] To generate the alternating magnetic field, the induction source may include at least one inductor, preferably at least one induction coil disposed around the receiving cavity. When the liquid conduit is induction heatable, the induction coil is disposed around the liquid conduit when the article is received around a portion of the liquid conduit disposed within the receiving cavity, in particular within the vaporization zone of the aerosol generating article.

[0062] At least one induction coil can be a helical coil or a flat planar coil, in particular a pancake coil or a curved planar coil. The use of a flat spiral coil allows for a robust and inexpensive compact design. The use of a helical induction coil advantageously allows for the generation of a homogeneous alternating magnetic field. As used herein, a "flat spiral coil" generally means a planar coil whose axis of the coil windings is perpendicular to the surface on which the coil is placed. The flat spiral induction coil can have any desired shape within the plane of the coil. For example, the flat spiral coil may have a circular shape, or generally an elliptical or rectangular shape. However, the term "flat spiral coil" as used herein encompasses both a planar coil and a flat spiral coil shaped to conform to a curved surface. For example, the induction coil may preferably be a "curved" planar coil disposed around a cylindrical coil support (e.g., a ferrite core). Further, the flat spiral coil may comprise, for example, two layers of a four-turn flat spiral coil, or a single layer of a four-turn flat spiral coil. At least one induction coil can be held within one of the main body or housing of the aerosol generating device.

[0063] In the aerosol generating article, if present, the inductively heatable liquid conduit may be configured such that when the article is received within the receiving cavity of the aerosol generating device, it is disposed off-center with respect to the axis of symmetry of the alternating magnetic field generated by the induction source. As described above, due to the off-center arrangement, i.e., the asymmetric arrangement, the liquid conduit is disposed within a region of the alternating magnetic field having a higher magnetic field density as compared to a symmetric center arrangement. As a result, the heating efficiency is enhanced.

[0064] The induction source may comprise an alternating current (AC) generator. The AC generator may be powered by the power supply of the aerosol generating device. The AC generator is operably connected to at least one induction coil. In particular, at least one induction coil may be an integral part of the AC generator. The AC generator is configured to generate a high-frequency oscillating current that passes through at least one induction coil to generate an alternating magnetic field. The AC current may be continuously supplied to at least one induction coil after the system is started, or may be intermittently supplied, for example, each time smoking occurs.

[0065] The induction source comprises a DC / AC converter connected to a DC power supply including an LC network, and the LC network preferably comprises a series connection of a capacitor and an inductor.

[0066] The induction source is preferably configured to generate a high-frequency magnetic field. As referred to herein, the high-frequency magnetic field can be in the range of 500 kHz (kilohertz) to 30 MHz (megahertz), particularly 5 MHz (megahertz) to 15 MHz (megahertz), preferably 5 MHz (megahertz) to 10 MHz (megahertz).

[0067] The aerosol generating device may further comprise a controller configured to control the operation of the heating process, preferably in a closed-loop configuration, in particular to control the heating of the aerosol-forming liquid to a predetermined operating temperature. The operating temperature used to heat the aerosol-forming liquid may be in the range of 100 degrees Celsius to 300 degrees Celsius, particularly in the range of 150 degrees Celsius to 250 degrees Celsius, for example, 230 degrees Celsius. These temperatures are typical operating temperatures for heating the aerosol-forming substrate without burning it.

[0068] The controller may be the overall controller of the aerosol generating device or may be part of the overall controller of the aerosol generating device. The controller may comprise a microprocessor, such as a programmable microprocessor, a microcontroller, or an application specific integrated circuit chip (ASIC) or other electronic circuitry having the ability to provide control. The controller may include at least one DC / AC inverter and / or a power amplifier, such as a class C power amplifier, or a class D power amplifier, or a class E power amplifier, etc., as further electronic components. In particular, the induction source may be part of the controller.

[0069] The aerosol generating device may comprise a power source, in particular a DC power source configured to provide a DC supply voltage and a DC supply current to the induction source. The power source is preferably a battery such as a lithium iron phosphate battery. Alternatively, the power source may be another form of charge storage device such as a capacitor. The power source may require recharging, i.e., the power source may be rechargeable. The power source may have a capacity that allows for sufficient energy storage for one or a plurality of user experiences. For example, the power source may have a capacity sufficient to allow for continuous generation of aerosol for about six minutes or a multiple of six minutes. In another embodiment, the power source may have a capacity sufficient to allow for a predetermined number of smoking sessions or discontinuous activation of the induction source.

[0070] In the case of an induction heating aerosol generating device, the aerosol generating device may further comprise a flux concentrator disposed around at least a portion of the induction coil and configured to direct an alternating magnetic field of at least one induction source towards the receiving cavity so as to distort it. Thus, when an article is received within the receiving cavity, the alternating magnetic field, if present, distorts towards the induction heatable liquid conduit. The flux concentrator preferably comprises a flux concentrator foil, in particular a multi-layer flux concentrator foil.

[0071] Further features and advantages of the aerosol generating system according to the present invention are already described above with respect to the aerosol generating article according to the present invention and equally apply.

[0072] According to the present invention, there is also provided a method for manufacturing an aerosol generating article according to and as described herein. The method comprises - extruding a hollow cylindrical storage body with open ends, the storage body having a constant cross-sectional profile along the longitudinal axis of the storage body; - providing a first end cap and a second end cap; - attaching the first end cap to the first end of the storage body and the second end cap to the second end of the storage body.

[0073] As previously mentioned, the outer tubular wall and the inner partition wall may be manufactured as separate parts by extrusion. Subsequently, the extruded inner partition wall may be attached between two opposing inner portions of the extruded outer tubular wall such that the inner void of the storage body is divided into a first compartment and a second compartment. Alternatively, the storage body may be extruded in one piece as a whole. That is, the outer tubular wall and the inner partition wall may be extruded together in one piece so as to be integral with each other. Thus, by extruding a hollow cylindrical storage body with open ends, an integrally extruded storage body can be provided.

[0074] The main advantages of extrusion over other manufacturing processes are the ability to create very complex cross-sections and the ability to function with brittle materials since they are only subjected to compressive and shear stresses during the extrusion press. Extrusion also forms parts with excellent surface finishes.

[0075] Generally, extrusion can be continuous or semi - continuous. Semi - continuous extrusion enables the direct manufacture of many individual parts. In contrast, continuous extrusion enables the manufacture of a continuous profile, which can then be separated into individual units, for example, by cutting. Thus, extruding an open - ended hollow cylindrical reservoir body can involve extruding the open - ended hollow cylindrical reservoir body by continuous extrusion or by semi - continuous extrusion.

[0076] Attaching a first end cap to the first end of the reservoir body and a second end cap to the second end of the reservoir body can involve attaching each end cap to its respective end of the reservoir body by at least one of form - fitting, force - fitting, or adhesive bonding. In particular, attaching the first end cap to the first end of the reservoir body can involve at least one of clamping, latching, welding, or adhering the first end cap to the first end of the reservoir body. Similarly, attaching the second end cap to the second end of the reservoir body can involve at least one of clamping, latching, welding, or adhering the second end cap to the second end of the reservoir body. Welding can particularly include laser welding or ultrasonic welding.

[0077] The method may further include filling the first compartment with an aerosol - forming liquid after attaching at least one of the first end cap or the second end cap to the first end and the second end of the reservoir body respectively. Filling the first compartment with the aerosol - forming liquid may occur before attaching each of the other of the first end cap and the second end cap to the first end and the second end of the reservoir body respectively.

[0078] The method may further include rounding the end face of the partition wall at the second end of the storage body before attaching the second end cap to the second end of the storage body. As described above, rounding the end face of the partition wall may promote fluid flow around the end of the partition wall facing the bottom end cap.

[0079] Further features and advantages of the method according to the present invention have already been described with respect to the aerosol generating article and the aerosol generating system according to the present invention and are therefore equally applicable.

[0080] The present invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0081] Example 1: An aerosol generating article for use with an aerosol generating device, An open-ended tubular, particularly hollow cylindrical storage body including an outer tubular wall and an inner partition wall extending between two opposing inner portions of the outer tubular wall so as to divide the inner void of the storage body into a first compartment and a second compartment, the first compartment and the second compartment being disposed adjacent to each other laterally along the longitudinal axis of the hollow cylindrical storage body, the open-ended tubular storage body; A first end cap attached to the first end of the storage body and closing so as to seal at least the first compartment at the first end of the storage body; A second end cap attached to the second end of the storage body and closing so as to seal the first compartment and the second compartment at the second end of the storage body, the second end cap including a fluid passage providing fluid communication between the first compartment and the second compartment, an aerosol generating article comprising. Example 2: The aerosol generating article according to Example 1, wherein the inner partition wall is parallel to the longitudinal axis of the storage body. Example 3: The storage part body is an aerosol generating article according to Example 2, which is an extruded body, particularly an integrally extruded body. Example 4: The arrangement of the inner partition wall within the outer tubular wall is asymmetric with respect to the cross-section of the storage part body that is perpendicular to the longitudinal axis of the storage part body, for the aerosol generating article according to any one of Examples 1 to 3. Example 5: The length extension of the inner partition wall in a direction parallel to the longitudinal axis of the storage part body is smaller than or equal to the length extension of the outer tubular wall, for the aerosol generating article according to any one of Examples 1 to 4. Example 6: The first end cap includes an outlet that provides fluid communication between the second compartment and the outside of the article, for the aerosol generating article according to any one of Examples 1 to 5. Example 7: The aerosol generating article according to Example 6 further comprises a filter disposed within or attached to the outlet. Example 8: The first end cap is formed as a mouthpiece, for the aerosol generating article according to any one of Examples 1 to 7. Example 9: The storage part body is made of one of plastic, particularly PET (polyethylene terephthalate), PP (polypropylene), PE (polyethylene), or PEEK (polyether ether ketone), for the aerosol generating article according to any one of Examples 1 to 8. Example 10: At least one of the first end cap and the second end cap is made of one of silicon, PET (polyethylene terephthalate), PP (polypropylene), PE (polyethylene), for the aerosol generating article according to any one of Examples 1 to 9. Example 11: The first end cap is attached to the storage part body by at least one of form fit, force fit, or adhesive bonding, for the aerosol generating article according to any one of Examples 1 to 10. Example 12: The second end cap is an aerosol generating article according to any one of Examples 1 to 11, which is attached to the storage part main body by at least one of form fitting, force fitting, or adhesive bonding. Example 13: The second end cap is an aerosol generating article according to any one of Examples 1 to 12, which includes a recess or a channel that provides fluid communication between the first compartment and the second compartment. Example 14: The maximum dimension of the second compartment between two opposing portions of the partition wall and the outer tubular wall is in the range of 0.2 millimeters to 5 millimeters, particularly 0.5 millimeters to 3 millimeters, preferably 1 millimeter to 2.5 millimeters, and is an aerosol generating article according to any one of Examples 1 to 13. Example 15: The volume of the first compartment is larger than the volume of the second compartment, and it is an aerosol generating article according to any one of Examples 1 to 14. Example 16: The volume of the second compartment is at most 50 percent, particularly at most 40 percent, preferably at most 30 percent, more preferably at most 20 percent of the volume of the first compartment, and it is an aerosol generating article according to any one of Examples 1 to 15. Example 17: The second compartment further includes a bushing disposed in a transverse direction, particularly in a direction perpendicular to the longitudinal axis of the storage part main body. The bushing divides the second compartment into a vaporization zone and a buffer storage part, and it is an aerosol generating article according to any one of Examples 1 to 16. Example 18: The aerosol generating article according to Example 17 further includes a liquid conduit that passes through the bushing for transporting the aerosol forming liquid from the buffer storage part to the vaporization zone. Example 19: The liquid conduit passes through the vaporization zone or faces the vaporization zone, and it is an aerosol generating article according to Example 18. Example 20: The liquid conduit comprises a core element, in particular a bundle of filaments, preferably a bundle of non-stranded filaments, or a mesh, of the aerosol-generating article according to any one of Examples 18 or 19. Example 21: The liquid conduit is inductively heatable, of the aerosol-generating article according to any one of Examples 18 to 20. Example 22: The liquid conduit comprises a liquid transport susceptor assembly, of the aerosol-generating article according to any one of Examples 18 to 21. Example 23: The buffer storage part comprises a total volume of at most 60 cubic millimeters, in particular at most 50 cubic millimeters, preferably at most 40 cubic millimeters, more preferably at most 30 cubic millimeters, and most preferably at most 20 cubic millimeters, of the aerosol-generating article according to any one of Examples 18 to 22. Example 24: The buffer storage part comprises a total volume of at least 5 cubic millimeters, in particular at least 10 cubic millimeters, preferably at least 15 cubic millimeters, of the aerosol-generating article according to any one of Examples 18 to 23. Example 25: The end face of the partition wall at the second end of the storage part body is rounded, of the aerosol-generating article according to any one of Examples 1 to 24. Example 26: Further comprising an aerosol-forming liquid contained at least within the first compartment, of the aerosol-generating article according to any one of Examples 1 to 25. Example 27: The storage part body has an outer cross-sectional shape that is circular, elliptical, oval, triangular, rectangular, square, hexagonal or polygonal, of the aerosol-generating article according to any one of Examples 1 to 26. Example 28: The outer tubular wall has an outer cross-sectional shape that is circular, elliptical, oval, triangular, rectangular, square, hexagonal or polygonal, of the aerosol-generating article according to any one of Examples 1 to 27. Example 29: An aerosol generation system comprising an aerosol generator and an aerosol generation article according to any one of Examples 1 to 28 for use with the apparatus. Example 30: A method for manufacturing an aerosol generation article according to any one of Examples 1 to 29, - Extruding a tubular, particularly open-ended hollow cylindrical storage part body, the storage part body having a constant cross-sectional profile along the longitudinal axis of the storage part body, - Providing a first end cap and a second end cap, - Attaching the first end cap to the first end of the storage part body and attaching the second end cap to the second end of the storage part body. Example 31: The method according to Example 30, wherein attaching the first end cap to the first end of the storage part body includes attaching the first end cap to the first end of the storage part body by at least one of form fitting, force fitting, or adhesive bonding. Example 32: The method according to any one of Examples 30 or 31, wherein attaching the second end cap to the second end of the storage part body includes attaching the second end cap to the second end of the storage part body by at least one of form fitting, force fitting, or adhesive bonding. Example 33: The method according to any one of Examples 30 to 32, wherein attaching the first end cap to the first end of the storage part body includes at least one of clamping, latching, welding, or adhering the first end cap to the first end of the storage part body. Example 34: The method according to any one of Examples 30 to 33, wherein attaching the second end cap to the second end of the storage part body includes at least one of clamping, latching, welding, or adhering the second end cap to the second end of the storage part body. Example 35: The method according to any one of Examples 30 to 34, further comprising filling the aerosol-forming liquid into the first compartment after attaching at least one of the first end cap and the second end cap to the first end of the storage unit body and the second end of the storage unit body, respectively. Example 36: Filling the aerosol-forming liquid into the first compartment occurs before attaching each other of the first end cap and the second end cap to the first end and the second end of the storage unit body, respectively, according to the method described in Example 35. Example 37: The method according to any one of Examples 30 to 36, further comprising rounding the end face of the partition wall at the second end of the storage unit body before attaching the second end cap to the second end of the storage unit body.

[0082] Here, the examples will be further described with reference to the following figures.

Brief Description of the Drawings

[0083]

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Mode for Carrying Out the Invention

[0084] Figure 1 schematically shows an aerosol generating article 40 according to a first embodiment of the present invention. As will be described in more detail below with respect to Figure 4, the aerosol generating article 40 is configured to be used with an inductive heating aerosol generator to vaporize an aerosol forming liquid 50 provided by the aerosol generating article 40. The article 40 comprises a substantially cylindrical article housing made of a liquid-impermeable rigid material, such as one of PET (polyethylene terephthalate), PP (polypropylene), or PE (polyethylene). The article housing includes a hollow cylindrical outer tubular wall 42, a first end cap 44, and a second end cap 43. The article further comprises a partition wall 41 as part of the article housing that divides the inner void of the outer tubular wall 42 into a first compartment 58 and a second compartment 59. The outer tubular wall 42 and the partition wall 41 together form a storage unit body according to the present invention. The first compartment 58 and the second compartment 59 are arranged adjacent to each other laterally along the longitudinal axis of the storage unit body. The first compartment 58 functions as a main storage unit 51 for storing the aerosol forming liquid 50. Within the second compartment 59, the article 40 comprises a substantially disk-shaped bushing 45 at approximately half of the length extension of the outer tubular wall 42 or the storage unit body respectively. The bushing 45 divides the inner void of the second compartment into two parts, namely, a vaporization cavity 53, and a capillary buffer storage unit 52 for storing the aerosol forming liquid due to capillary action. This will be described in more detail below. The first end cap 44 closes to seal the storage unit body at the first end 57 of the storage unit body. At the opposite second end 56, the storage unit body is closed by the second end cap 43. The second end cap 43 includes a fluid passage that provides fluid communication between the first compartment 58 and the second compartment 59, and thus between the capillary buffer storage unit 52 and the main storage unit 51. The fluid passage is formed by a recess within the second end cap 43. As can be seen in Figure 1, the recess is formed such that the main storage unit 51 directly extends into the capillary buffer storage unit 52, allowing the aerosol forming liquid 50 to freely flow from the main storage unit 51 into the capillary buffer storage unit 52.To promote fluid flow around the free end of the partition wall 41 facing the second end cap 43, the free end of the partition wall 41 includes a rounded edge.

[0085] As can be seen in FIGS. 2 and 3, these figures show cross-sections through the aerosol-generating article according to FIG. 1 along lines A-A and B-B respectively, and the inner partition wall 41 is separated from the outer tubular wall 42. The outer tubular wall 42 and the partition wall 41 are preferably manufactured separately from each other by extrusion. Thereafter, the outer tubular wall 42 and the partition wall 41 may be assembled to form the storage part body according to the present invention. As can further be seen in FIGS. 2 and 3, the inner partition wall 41 is asymmetrically attached between two opposing inner portions of the outer tubular wall 42, parallel to the central axis of the outer tubular wall 42, so as to divide the inner void of the storage part body into a first compartment 58 and a second compartment 59 smaller than the first compartment. In this configuration, the outer tubular wall 42 and the partition wall 41 may be attached to each other by an adhesive bond, for example, welding or adhesion. Advantageously, the adhesive bond provides a seal between the first compartment 58 and the second compartment 59 and the partition wall 41 and the outer tubular wall 42 are integrated.

[0086] As another method, as shown in FIG. 5, the inner partition wall 41 and the outer tubular wall 42 may be integral with each other. In this configuration, the outer tubular wall 42 and the partition wall 41 are also manufactured together by extrusion, which may result in an integrally extruded storage part body. Advantageously, the integrally extruded storage part body is particularly easy and inexpensive to manufacture. Furthermore, the integrally extruded storage part body does not require a seal between the first compartment 58 and the second compartment 59 and the partition wall 41 and the outer tubular wall 42 are integrated.

[0087] Generally, the aerosol-generating article 40 may be an aerosol-generating article for single use or an aerosol-generating article for multiple uses. In the latter case, the aerosol-generating article 40 may be refillable. That is, the main storage part 51 may be refillable with the aerosol-forming liquid 50 after depletion.

[0088] Article 40 further comprises a liquid conduit 70 in fluid communication with the capillary buffer reservoir 52 for transporting the aerosol-forming liquid 50 from the capillary buffer reservoir 52 into the vaporization cavity 53. As can be seen particularly in FIGS. 2 and 3, the liquid conduit 70 according to the present embodiment is a non-stranded bundle of filaments comprising a plurality of filaments 71, 72 arranged parallel to each other. Due to the arrangement of the filaments 71, 72 in the bundle of filaments and due to the small diameter of the filaments 71, 72, the liquid conduit 70 includes capillary channels formed between the filament 71 and the filament 72. These channels provide capillary action along the length extension of the liquid conduit 70 and thus enable the aerosol-forming liquid 50 to be transported from the capillary buffer reservoir 52 to the vaporization cavity 53.

[0089] In addition to the liquid transport characteristics, the liquid conduit 70 of the present embodiment is also configured for inductive heating. For that purpose, the liquid conduit 70 includes at least a plurality of first filaments 71 comprising a first susceptor material optimized for heat generation. The liquid conduit 70 may also include a plurality of second filaments 72 comprising a second susceptor material that functions as a temperature marker as described above. Due to the sensitive nature of the filament material, the liquid conduit 70 has the ability to be inductively heated in an alternating magnetic field and thus has the ability to vaporize the aerosol-forming liquid in thermal contact with the filaments 71, 72. Therefore, the liquid conduit 70 has the ability to perform two functions: transporting and heating the aerosol-forming liquid. For this reason, the liquid conduit is also shown as a liquid transport susceptor assembly.

[0090] As can be seen in FIG. 1, the liquid conduit 70 passes through the opening of the bushing 45 such that a first portion of the liquid conduit 70 is disposed within the buffer reservoir 52 and a second portion is disposed within the vaporization cavity 53. The opening through the bushing 45 functions not only as a feed-through for the liquid conduit, but also to bundle the filaments 71, 72, i.e., to hold the filaments 71, 72 together. Further, the opening functions to fix the position of the liquid conduit 70 relative to the article housing. As can be further seen in FIGS. 2 and 3, the bundle of filaments of the liquid conduit 70 has a substantially circular cross-section, which is particularly easy to manufacture.

[0091] The first portion of the liquid conduit 70 is disposed within the buffer reservoir 52 and is thus immersed in the aerosol-forming liquid 50, acting as an immersion section 75 for conveying the aerosol-forming liquid 50 from the buffer reservoir 52 to the second portion of the liquid conduit 70. In the vaporization cavity 53, the second portion acts at least in part as a heating section 76 for vaporizing the aerosol-forming liquid 50 when exposed to an alternating magnetic field to inductively heat the filaments 71, 72. This is described in more detail below with respect to FIG. 4.

[0092] As can be further seen in FIG. 1, the article 40 includes at least one air inlet 46 into the vaporization cavity 53 through the reservoir body, allowing air to enter the vaporization cavity 53. The air inlet 46 can be configured to provide an air flow to, or around, the heating section 76 of the liquid conduit 70. The air inlet 46 may be a hole through the reservoir body. Similarly, the air inlet 46 may be a nozzle configured to direct the air flow to a specific target location on the liquid conduit 70. Further, the article 40 includes a tapered mouthpiece 47 that is attached to the first end cap 44 and configured to be taken into a user's mouth for smoking. The mouthpiece 47 further includes a filter 55 and an air outlet 48. The mouthpiece 47 is in fluid communication with the vaporization cavity 53 through an outlet 49 within the first end cap 44. Thus, when a user smokes through the mouthpiece 47, air is drawn into the vaporization cavity 53 through the air inlet 46. From there, the air passes through the opening 49 into the mouthpiece 47 and further through the filter 55 and the air outlet 48 into the user's mouth. In the vaporization cavity 53, the aerosol-forming liquid vaporized from the heating section 76 of the liquid conduit 70 is exposed to the air passing through the article 40 to form an aerosol, and then the aerosol can be drawn through the mouthpiece 47.

[0093] Figure 4 schematically shows an aerosol generation system 80 according to an exemplary embodiment of the present invention. The system 80 includes the aerosol generating article 40 shown in FIGS. 1 - 3, and an electrically operated aerosol generating device 60 having the ability to interact with the article 40 to generate an aerosol. For this purpose, the aerosol generating device 60 includes a receiving cavity 62 formed within a device housing 61 at a proximal end of the device 60. The receiving cavity 62 is configured to removably receive at least a portion of the aerosol generating article 40. In particular, the aerosol generating device is configured to inductively heat a heating section 76 of a liquid conduit 70 to vaporize an aerosol forming liquid 50 that is conveyed from a capillary buffer reservoir 52 to a heating section 76 within a vaporization cavity 53 via an immersion section 75. For this purpose, the aerosol generating device 60 includes an induction source including an induction coil 32. In the present embodiment, the induction coil 32 is a single helical coil arranged and configured to generate a substantially homogeneous alternating magnetic field within the receiving cavity 62. As can be seen in FIG. 4, the induction coil 32 is arranged around a proximal end portion of the receiving cavity 62 such that it only surrounds the heating section 76 of the liquid conduit 70 when the aerosol generating article 40 is received within the receiving cavity 62. Thus, during use of the device 60, the induction coil 32 generates an alternating magnetic field that only penetrates the heating section 76 of the liquid conduit 70 within the vaporization cavity 53 of the article 40. In contrast, due to the local heating, the immersion section 75 of the liquid conduit 70 remains at a temperature below the vaporization temperature. Thus, boiling of the aerosol forming liquid 50 within the capillary buffer reservoir 52 and the main reservoir 51 is prevented. Thus, during use, the liquid conduit 70 includes a temperature profile along its length extension having high and low temperature sections. More specifically, the temperature profile shows a temperature rise from a temperature below the vaporization temperature T_vap of the aerosol forming liquid 50 within the immersion section 75 to a temperature above each vaporization temperature within the heating section 76.

[0094] The actual temperature profile formed during the use of susceptor assembly 10 depends on the thermal conductivity and the length of liquid conduit 70. Therefore, in order to have a sufficient temperature gradient between the immersion section 75 and the heating section 76, liquid conduit 70 requires a specific total length. For the present embodiment, the total length of liquid conduit 70 may be in the range of 5 millimeters to 50 millimeters, particularly 10 millimeters to 40 millimeters, preferably 10 millimeters to 30 millimeters, and more preferably 10 millimeters to 20 millimeters.

[0095] Liquid conduit 70 is disposed offset from the geometric central axis of aerosol generating article 40. For this reason, liquid conduit 70 is disposed offset from the axis of symmetry of the alternating magnetic field generated by induction coil 32 when article 40 is received within cavity 62 of device 60. Advantageously, due to the offset arrangement, liquid conduit 70 is disposed within a region of the alternating magnetic field having a higher magnetic field density as compared to a symmetric central arrangement. As a result, the heating efficiency is enhanced.

[0096] Aerosol generating device 60 further comprises a controller 64 for controlling the operation of aerosol generating system 80, particularly for controlling the heating operation. Further, aerosol generating device 60 comprises a power source 63 for providing power to generate the alternating magnetic field. Power source 63 is preferably a battery such as a lithium iron phosphate battery. Power source 63 may have a capacity that allows for sufficient energy storage for more than one user experience. Both controller 64 and power source 63 are disposed in the distal portion of aerosol generating device 60.

[0097] Here, the function of the capillary buffer storage unit 52 will be described in more detail with reference to FIGS. 6, 7, and 8. FIG. 6 shows the aerosol-generating article 40 according to FIG. 1, but does not include the capillary buffer storage unit. Further, in contrast to FIG. 1, FIG. 6 shows the article 40 in a substantially horizontal orientation. Due to the different orientation, the aerosol-forming liquid 50 within the article 40 is redistributed in such a way that (depending on the fluid level) the liquid conduit 70 does not contact the aerosol-forming liquid 50. As a result, if the article is used for a specific period of time in this orientation, the delivery of the aerosol-forming liquid to the vaporization zone 53 is interrupted, which causes a rapid decrease in aerosol formation or even a functional stop. The purpose of the buffer storage unit 52 is to correct this. Basically, the buffer storage unit 52 is in fluid communication with the main storage unit 51 and the liquid conduit 70, and is configured to confine a specific amount of aerosol-forming liquid due to capillary action, independent of the orientation of the article, providing a small-volume storage unit. For this purpose, at least one dimension of the capillary buffer storage unit 52 is selected to be about the effective length of the capillary, which is usually in the range of a few millimeters for most liquids. In this embodiment, the capillary action of the buffer storage unit 52 is caused by the fact that the maximum distance D between the opposing portions of the partition wall 41 and the inner surface of the outer tubular wall 42, shown in FIGS. 3 and 7, is within the range of a few millimeters. For example, the maximum distance D may be within the range of 1 millimeter to 5 millimeters. Thus, the capillary effect is dominant over gravity within the capillary buffer storage unit 52. As a result, after the aerosol-forming liquid 50 is filled into the buffer storage unit 52, when the orientation of the article is changed, for example, when the article 40 is rotated from a substantially upright position as shown in FIG. 1 to a substantially horizontal position as shown in FIG. 7, or even to an upside-down position as shown in FIG. 8, the aerosol-forming liquid 50 is prevented from flowing back into the main storage unit 51. Therefore, independent of the orientation of the article, the buffer storage unit 40 reliably confines liquid aerosol formation due to its small-volume capillary action, similar to the buffer storage unit of a fountain pen.Moreover, the capillary action along the liquid conduit is still large enough to transport the trapped liquid from the capillary buffer storage unit 52 to the vaporization zone. The volume of the buffer storage unit is selected to provide sufficient liquid for several smoking sessions, independent of the orientation of the article. Thus, the total volume of the capillary buffer storage unit 52 may be at least 5 cubic millimeters, particularly at least 10 cubic millimeters, preferably at least 15 cubic millimeters.

[0098] Figures 9 and 10 schematically illustrate a second exemplary embodiment of an aerosol-generating article according to the present invention. Generally, the aerosol-generating article 240 according to FIGS. 9 and 10 is similar to the aerosol-generating article 40 shown in FIG. 1. Accordingly, the same or similar features are denoted by the same reference numerals, but incremented by 200 only. In contrast to the article 40 shown in FIG. 1, the article 240 according to FIGS. 9 and 10 comprises a liquid conduit 270, a buffer reservoir 252, and a vaporization zone 253 disposed symmetrically with respect to the geometric central axis of 40. For this purpose, the cylindrical partition wall 241 is coaxially disposed within the cylindrical outer tubular wall 242 so as to divide the inner void of the cylindrical outer tubular wall 242 into a hollow cylindrical first compartment 258 and a cylindrical second compartment 259 coaxially surrounded by the first compartment 258. The first compartment 258 forms a hollow cylindrical main reservoir 251, and the second compartment 259 forms a cylindrical vaporization zone 253. The first end cap 244 is attached to the first end of the reservoir body including the partition wall 241 and the outer tubular wall 242. The first end cap 244 closes to seal the first compartment 258 at the first end of the reservoir body. At the opposite end, the reservoir body is closed by a second end cap 243 including a recess similar to the bottom end cap 43 of the article 40 shown in FIG. 1. At the bottom, the vaporization cavity 253 is closed by a disk-shaped bushing 245. Here, the capillary buffer reservoir 252 is formed between the inner surface of the second end cap 243 on one side, the end face of the cylindrical partition wall 241 on the other side, and the disk-shaped bushing 245. That is, the capillary buffer reservoir 252 is basically formed by a part of the recess-like fluid passage in the second end cap 243. The distance D between the inner surface of the bottom end cap 243, the end face of the cylindrical partition wall 241, and the disk-shaped bushing 245 is selected to be in the range of, for example, 1 millimeter to 5 millimeters, which is about the effective length of the capillary.Therefore, after the aerosol-forming liquid is filled, the buffer storage part 252 confines a specific amount of the aerosol-forming liquid due to capillary action even when the orientation of the article 240 is changed, for example, when the article 40 is rotated from a substantially upright position as shown in FIG. 9 to an upside-down position as shown in FIG. 10. Thus, the immersion section 275 of the liquid conduit 270 is always in contact with the aerosol-forming liquid, independent of the position of the article. The volume of the capillary buffer storage part 252 is selected such that the amount of the aerosol-forming liquid that can be confined is sufficient for at least several smoking sessions.

[0099] In this embodiment, the cylindrical partition wall 241 and the outer tubular wall 242 are separate parts that can be manufactured by extrusion molding. The first end cap 243 and the second end cap 244 can be used to hold the partition wall 241 and the outer tubular wall 242 together.

[0100] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing amounts, quantities, percentages, etc. are to be understood as being modified in all instances by the term "about". Also, all ranges include the disclosed maximum and minimum points, and any intermediate ranges therebetween, whether or not specifically enumerated herein. Thus, in this context, a number A is understood to be A ± 5%. In this context, the number A may be considered to include numerical values within the general standard error of the measured value of the property being modified by the number A. The number A may deviate by the percentages listed above, provided that in some instances as used in the appended claims, the amount by which A deviates does not substantially affect the basic and novel characteristics of the claimed invention. Also, all ranges include the disclosed maximum and minimum points, and any intermediate ranges therebetween, whether or not specifically enumerated herein.

Claims

1. An aerosol generating article for use with an aerosol generating device, comprising: An open-ended hollow cylindrical storage body including an outer tubular wall and an inner partition wall extending between two opposing inner portions of the outer tubular wall so as to divide the inner void of the storage body into a first compartment and a second compartment, the first compartment and the second compartment being arranged adjacent to each other laterally along the longitudinal axis of the hollow cylindrical storage body; A first end cap attached to the first end of the storage body and closing to seal at least the first compartment at the first end of the storage body; A second end cap attached to the second end of the storage body and closing to seal the first compartment and the second compartment at the second end of the storage body, the second end cap including a fluid passage providing fluid communication between the first compartment and the second compartment.

2. The aerosol generating article according to claim 1, wherein the storage body is an extruded body.

3. The aerosol generating article according to any one of claims 1 or 2, wherein the arrangement of the inner partition wall within the outer tubular wall is asymmetric with respect to a cross-section of the storage body that is perpendicular to the longitudinal axis of the storage body.

4. The aerosol generating article according to any one of claims 1 to 3, wherein the first end cap includes an outlet providing fluid communication between the second compartment and the exterior of the article.

5. The aerosol generating article according to any one of claims 1 to 4, wherein the first end cap is formed as a mouthpiece.

6. The aerosol generating article according to any one of claims 1 to 5, wherein the first end cap and the second end cap are attached to the storage body by at least one of form fit, force fit, or adhesive bonding.

7. The aerosol generating article according to any one of claims 1 to 6, wherein the second end cap includes a recess or channel providing fluid communication between the first compartment and the second compartment.

8. The maximum dimension of the second compartment between two opposing portions of the partition wall and the outer tubular wall is in the range of 0.2 millimeters to 5 millimeters, the aerosol generating article according to any one of claims 1 to 7.

9. The volume of the second compartment is at most 50 percent of the volume of the first compartment, the aerosol generating article according to any one of claims 1 to 8.

10. The second compartment is provided with a bushing disposed in a transverse direction with respect to the longitudinal axis of the storage unit body, and the bushing divides the second compartment into a vaporization zone and a buffer storage unit, the aerosol generating article according to any one of claims 1 to 9.

11. The aerosol generating article according to claim 10, further comprising a liquid conduit passing through the bushing for transporting the aerosol-forming liquid from the buffer storage unit to the vaporization zone.

12. The aerosol generating article according to claim 11, wherein the liquid conduit is inductively heatable.

13. An aerosol generating system comprising an aerosol generating device and an aerosol generating article according to any one of claims 1 to 12 for use with the device.

14. A method for manufacturing an aerosol generating article according to any one of claims 1 to 12, comprising: - extruding the hollow cylindrical storage unit body with an open end, the storage unit body having a constant cross-sectional profile along the longitudinal axis of the storage unit body; - providing the first end cap and the second end cap; - attaching the first end cap to the first end of the storage unit body and attaching the second end cap to the second end of the storage unit body.

15. The method according to claim 14, further comprising filling the aerosol-forming liquid into the first compartment after attaching at least one of the first end cap and the second end cap to the first end and the second end of the storage unit body, respectively.

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