WO2024231239A1

WO2024231239A1 - Aerosol-generating article with downstream obstruction

Info

Publication number: WO2024231239A1
Application number: PCT/EP2024/062177
Authority: WO
Inventors: Matteo Bologna
Original assignee: Philip Morris Products SA
Current assignee: Philip Morris Products SA
Priority date: 2023-05-10
Filing date: 2024-05-03
Publication date: 2024-11-14
Anticipated expiration: 2025-11-10
Also published as: CN121001588A

Abstract

The invention relates to an aerosol-generating article comprising a mouthpiece portion. The mouthpiece portion is hollow and cylindrical. The mouthpiece portion comprises a sheet. The sheet is arranged one or both of in the mouthpiece portion and forming an inner sidewall of the mouthpiece portion. The sheet comprises protrusions extending at an angle from the sheet. The invention further relates to a method for forming a mouthpiece portion of an aerosol-generating article.

Description

AEROSOL-GENERATING ARTICLE WITH DOWNSTREAM OBSTRUCTION

The present invention relates to an aerosol-generating article and a method for forming a mouthpiece portion for an aerosol-generating article.

It is known to provide an aerosol-generating article for generating an inhalable vapor. Such articles may comprise aerosol-forming substrate which is heated to a temperature at which one or more components of the aerosol-forming substrate are volatilised without burning the aerosol-forming substrate. Aerosol-forming substrate may be provided as part of a substrate portion of the aerosol-generating article. The aerosol-generating article may have a rod shape for insertion of the aerosol-generating article into a cavity, such as a heating chamber, of an aerosol-generating device. Due to the relatively low temperatures utilized for vaporizing the aerosol-forming substrate, it may not be necessary to provide a filter downstream of the substrate portion. However, it may be unpleasant for user to have a hollow portion downstream of the substrate portion. Further, it may be unpleasant for user to have lose aerosol-forming substrate potentially falling out of the downstream open end of the aerosol-forming article.

It would be desirable to have an aerosol-generating article without the need of a downstream filter. It would be desirable to have an aerosol-generating article preventing aerosol-forming substrate from falling out of the aerosol-generating article downstream of a substrate portion of the aerosol-generating article. It would be desirable to have an aerosolgenerating article preventing an unobstructed view of a substrate portion of the aerosolgenerating article.

According to an embodiment of the invention there may be provided an aerosolgenerating article comprising a mouthpiece portion. The mouthpiece portion may be hollow and cylindrical. The mouthpiece portion may comprise a sheet. The sheet may be arranged one or both of in the mouthpiece portion and forming an inner sidewall of the mouthpiece portion. The sheet may comprise protrusions may extend at an angle from the sheet.

According to an embodiment of the invention there is provided an aerosol-generating article comprising a mouthpiece portion. The mouthpiece portion is hollow and cylindrical. The mouthpiece portion comprises a sheet. The sheet is arranged one or both of in the mouthpiece portion and forming an inner sidewall of the mouthpiece portion. The sheet comprises protrusions extending at an angle from the sheet.

The sheet of the mouthpiece portion of the aerosol-generating article and particularly the protrusions thereof may prevent aerosol-forming substrate from falling out of the aerosolgenerating article downstream of a substrate portion of the aerosol-generating article. The sheet of the mouthpiece portion of the aerosol-generating article and particularly the protrusions thereof may prevent an unobstructed view of the substrate portion of the aerosolgenerating article. The sheet of the mouthpiece portion of the aerosol-generating article and particularly the protrusions thereof may have a filtering effect. This filtering effect may be sufficient due to the reduced amount of unwanted components of the generated aerosol of the heat-not-burn aerosol-generating article.

The mouthpiece portion may be a most proximal portion of the aerosol-generating article. The mouthpiece portion may be a most downstream portion of the aerosol-generating article.

The mouthpiece portion may have a cardboard sidewall. The mouthpiece portion may be configured dimensionally stable such that the mouthpiece portion can withstand a user holding the mouthpiece portion between his or her lips or fingers.

The sheet may be flat. The sheet may be longer than wide. The sheet may be arranged fully within the hollow mouthpiece portion.

The aerosol-generating article may further comprise a substrate portion upstream of the mouthpiece portion.

The substrate portion may directly abut the mouthpiece portion. The substrate portion may contain aerosol-forming substrate.

The aerosol-generating article may comprise a tipping paper. The tipping paper may be arranged at least partly surrounding the mouthpiece portion and the substrate portion. The tipping paper may hold the mouthpiece portion and the substrate portion together.

The sheet may be folded and arranged in the mouthpiece portion.

The sheet may be folded in an omega shape. The sheet may be folded without sharp folding edges. In other words, the folding edges of the sheet may be rounded. Again in other words, the “folding” of the sheet may be a bending to avoid sharp folding edges.

The sheet may be folded at least 2 times, preferably at least 3 times, more preferably at least 4 times.

The sheet may have a length of between 2 and 6 times an inner diameter of the mouthpiece portion, preferably of between 3 and 5 times the inner diameter of the mouthpiece portion, more preferably of 4 times the inner diameter of the mouthpiece portion.

An extension plane of the sheet may be parallel to a longitudinal axis of the aerosolgenerating article.

The protrusions of the sheet may extend at an angle from an extension plane of the sheet. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 10 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 20 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 30 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 40 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 50 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 60 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 70 degrees and 90 degrees. The protrusions of the sheet may extend from the extension plane of the sheet at an angle of between 80 degrees and 90 degrees. The protrusions of the sheet may extend perpendicularly from the extension plane of the sheet. The extension plane of the sheet may be defined before the folding of the sheet. Alternatively, the extension plane may be a tangential plane at the point of contact of a protrusion with the sheet.

An extension plane of one ore more of the protrusions may be parallel to the longitudinal axis of the aerosol-generating article. The extension plane of all of the protrusions may be parallel to the longitudinal axis of the aerosol-generating article.

The sheet may have a thickness of between 50 micrometres and 1000 micrometres, preferably between 200 micrometres and 500 micrometres.

The sheet may be wound to form an innermost layer of the mouthpiece portion.

In this embodiment, the sheet may not be folded and arranged inside of the mouthpiece portion. Instead, the sheet may form the innermost layer of the mouthpiece portion. The innermost layer of the mouthpiece portion may also be denoted as sidewall or inner sidewall of the mouthpiece portion.

The sheet may be wound on a mandrel to form the innermost layer of the mouthpiece portion. The winding may be a spiral winding.

After winding of the sheet, the mandrel may be removed so that he hollow cylindrical mouthpiece portion is created. The wound sheet may be cut to size for the individual mouthpiece portions. During the winding of the sheet on the mandrel, the protrusion of the sheet may be pressed against the sheet. After the winding of the sheet on the mandrel, the protrusion of the sheet may be unfolded so as the be arranged in the angled arrangement.

The protrusions may extend radially inwards from the innermost layer of the mouthpiece portion.

The protrusions may extend radially inwards to obstruct a view of the substrate portion from the open end of the mouthpiece portion.

The mouthpiece portion may have an open downstream end. The open downstream end may enable flow of aerosol out of the open downstream end. The hollow configuration of the mouthpiece portion may enable aerosol to flow through the mouthpiece portion. The sheet may be arranged to not or negligibly influence a resistance to draw of the mouthpiece portion. Due to the hollow nature of the mouthpiece portion and due to the arrangement of the sheet, the mouthpiece portion may have no or only a negligible resistance to draw.

The sheet may be fluid impermeable. As a consequence, the innermost layer of the mouthpiece portion may be fluid impermeable. In other words, the sheet may prevent lateral airflow into the mouthpiece portion. In an alternative embodiment, the sheet may be fluid permeable. In this embodiment, the mouthpiece portion may be fluid permeable for lateral airflow. This may enable lateral airflow into the mouthpiece portion. Lateral airflow into the mouthpiece portion may enable ambient air to be drawn into the mouthpiece portion during a draw of a user on the aerosol-generating article. This may facilitate mixing of ambient air with air being drawn axially through the aerosol-generating article and comprising volatilized aerosol-forming substrate. This mixing may cool the air comprising the volatilized aerosolforming substrate and may enable formation of the aerosol due to condensation of the volatilized aerosol-forming substrate.

Axial gaps may be arranged between the individual protrusions to enable airflow through the protrusions.

The protrusions may not or negligibly contribute to the resistance to draw of the mouthpiece portion.

The protrusions may be arranged to prevent or reduce unwanted residues or aerosolforming substrate from the substrate portion from falling through the protrusions.

The distance between protrusions may be less than a mean particle size of aerosolforming substrate particles.

The sheet may comprise cardboard. The sheet may be made from cardboard.

The sheet may be spirally wound to form the innermost layer of the mouthpiece portion.

The sheet may be may overlappingly spirally wound to form the innermost layer of the mouthpiece portion.

The portion of the sheet overlapped during winding may be coated with an adhesive.

The portion of the sheet overlapped during winding may be an attachment portion of the sheet. The attachment portion may be coated with adhesive.

The sheet may comprise at least a first sheet and an overlapping second sheet. One or both of the first sheet and the second sheet may comprise the protrusions.

The sheet may comprise at least a third sheet and a fourth sheet. One or more of the first sheet, the second sheet, the third sheet and the fourth sheet may overlap. One or more of the first sheet, the second sheet, the third sheet and the fourth sheet may comprise the protrusions.

The protrusions may have an extension direction perpendicular to a longitudinal axis of the aerosol-generating article.

The protrusions may have a triangular, rectangular, disc, teardrop or bristle shape. The protrusions may be flaps. The protrusions may be bristles. The protrusions may be one or both of hooks and loops similar or identical to a Velcro closure.

The protrusions may be formed integrally with the sheet.

Alternatively, the protrusions may be attached to the sheet. The protrusions may be attached to the sheet with an elastic adhesive. This may facilitate folding of the protrusions against the sheet during winding of the sheet on the mandrel. This may facilitate unfolding of the protrusions from the sheet after winding of the sheet on the mandrel.

One or both of the sheet and the protrusions may comprise, preferably consists of, one or more of fibers, threads and yarn.

One or both of the sheet and the protrusions may comprise, preferably consists of, cellulose, cellulose pulp derived from wood, cotton, rice, lignocellulosic materials, paper, wool, cotton, silk, linen, raffia, coconut, bamboo or jute.

The sheet may be biodegradable. The protrusions may be biodegradable.

The protrusions may be formed along a long side edge of the sheet. The protrusions may extend from a long side edge of the sheet.

The adhesive layer may be coated on a portion of the sheet opposite to the long side edge at which the protrusions are formed.

The protrusions may comprise a coating.

The coating may be configured to trap one or both of phenols and flu gases or the coating may comprise a flavourant.

The invention further relates to a method for forming a mouthpiece portion of an aerosol-generating article, wherein the method may comprise the following steps: providing a sheet comprising protrusions; wrapping the sheet around a mandrel thereby forming an innermost layer of a hollow cylindrical mouthpiece portion or arranging the sheet in the mouthpiece portion; and extending the protrusions in an angled direction with respect to the sheet.

The method may comprise, before wrapping of the sheet, folding of the protrusions against the sheet.

The protrusions may be configured to automatically unfold after removal of the wrapped sheet from the mandrel. The invention may further relate to an aerosol-generating device configured to be used with an aerosol-generating article as described herein.

The invention may further relate to an aerosol-generating system comprising an aerosol-generating device an aerosol-generating article as described herein.

The aerosol-generating device may comprise a cavity for receiving the aerosolgenerating article.

The aerosol-generating device may comprise a heating element for heating the aerosol-forming substrate.

The aerosol-generating device may comprise a controller for controlling the operation fo the heating element.

The aerosol-generating device may comprise a power supply for powering the heating element and the controller.

As used herein, the terms ‘proximal’, ‘distal’, ‘downstream’ and ‘upstream’ are used to describe the relative positions of components, or portions of components, of the aerosolgenerating device in relation to the direction in which a user draws on the aerosol-generating device or the aerosol-generating article during use thereof.

The aerosol-generating device may comprise a mouth end through which in use an aerosol exits the aerosol-generating device and is delivered to a user. The mouth end may also be referred to as the proximal end. In use, a user draws on the proximal or mouth end of the aerosol-generating device in order to inhale an aerosol generated by the aerosolgenerating device. Alternatively, a user may directly draw on an aerosol-generating article inserted into an opening at the proximal end of the aerosol-generating device. The opening at the proximal end may be an opening of the cavity. The cavity may be configured to receive the aerosol-generating article. The aerosol-generating device comprises a distal end opposed to the proximal or mouth end. The proximal or mouth end of the aerosol-generating device may also be referred to as the downstream end and the distal end of the aerosolgenerating device may also be referred to as the upstream end. Components, or portions of components, of the aerosol-generating device may be described as being upstream or downstream of one another based on their relative positions between the proximal, downstream or mouth end and the distal or upstream end of the aerosol-generating device.

As used herein, an ‘aerosol-generating device’ relates to a device that interacts with an aerosol-forming substrate to generate an aerosol. The aerosol-forming substrate may be part of an aerosol-generating article, for example part of a smoking article. An aerosolgenerating device may be a smoking device that interacts with an aerosol-forming substrate of an aerosol-generating article to generate an aerosol that is directly inhalable into a user’s lungs thorough the user's mouth. An aerosol-generating device may be a holder. The device may be an electrically heated smoking device. The aerosol-generating device may comprise a housing, electric circuitry, a power supply, a heating chamber and a heating element.

As used herein with reference to the present invention, the term ‘smoking’ with reference to a device, article, system, substrate, or otherwise does not refer to conventional smoking in which an aerosol-forming substrate is fully or at least partially combusted. The aerosol-generating device of the present invention is arranged to heat the aerosol-forming substrate to a temperature below a combustion temperature of the aerosol-forming substrate, but at or above a temperature at which one or more volatile compounds of the aerosolforming substrate are released to form an inhalable aerosol.

The aerosol-generating device may comprise electric circuitry. The electric circuitry may comprise a microprocessor, which may be a programmable microprocessor. The microprocessor may be part of a controller. The electric circuitry may comprise further electronic components. The electric circuitry may be configured to regulate a supply of power to the heating element. Power may be supplied to the heating element continuously following activation of the aerosol-generating device or may be supplied intermittently, such as on a puff-by-puff basis. The power may be supplied to the heating element in the form of pulses of electrical current. The electric circuitry may be configured to monitor the electrical resistance of the heating element, and preferably to control the supply of power to the heating element dependent on the electrical resistance of the heating element.

The aerosol-generating device may comprise a power supply, typically a battery, within a main body of the aerosol-generating device. In one embodiment, the power supply is a Lithium-ion battery. Alternatively, the power supply may be a Nickel-metal hydride battery, a Nickel cadmium battery, or a Lithium based battery, for example a Lithium-Cobalt, a Lithium-lron-Phosphate, Lithium Titanate or a Lithium-Polymer battery. As an alternative, the power supply may be another form of charge storage device such as a capacitor. The power supply may require recharging and may have a capacity that enables to store enough energy for one or more usage experiences; for example, the power supply may have sufficient capacity to continuously generate aerosol for a period of around six minutes or for a period of a multiple of six minutes. In another example, the power supply may have sufficient capacity to provide a predetermined number of puffs or discrete activations of the heating element.

The cavity of the aerosol-generating device may have an open end into which the aerosol-generating article is inserted. The open end may be a proximal end. The cavity may have a closed end opposite the open end. The closed end may be the base of the cavity. The closed end may be closed except for the provision of air apertures arranged in the base. The base of the cavity may be flat. The base of the cavity may be circular. The base of the cavity may be arranged upstream of the cavity. The open end may be arranged downstream of the cavity. The cavity may have an elongate extension. The cavity may have a longitudinal central axis. A longitudinal direction may be the direction extending between the open and closed ends along the longitudinal central axis. The longitudinal central axis of the cavity may be parallel to the longitudinal axis of the aerosol-generating device.

The cavity may be configured as a heating chamber. The cavity may have a cylindrical shape. The cavity may have a hollow cylindrical shape. The cavity may have a shape corresponding to the shape of the aerosol-generating article to be received in the cavity. The cavity may have a circular cross-section. The cavity may have an elliptical or rectangular cross-section. The cavity may have an inner diameter corresponding to the outer diameter of the aerosol-generating article.

An airflow channel may run through the cavity. Ambient air may be drawn into the aerosol-generating device, into the cavity and towards the user through the airflow channel. Downstream of the cavity, a mouthpiece may be arranged or a user may directly draw on the aerosol-generating article. The airflow channel may extend through the mouthpiece.

In any of the aspects of the disclosure, the heating element may comprise an electrically resistive material. Suitable electrically resistive materials include but are not limited to: semiconductors such as doped ceramics, electrically "conductive" ceramics (such as, for example, molybdenum disilicide), carbon, graphite, metals, metal alloys and composite materials made of a ceramic material and a metallic material. Such composite materials may comprise doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbides. Examples of suitable metals include titanium, zirconium, tantalum platinum, gold and silver. Examples of suitable metal alloys include stainless steel, nickel-, cobalt-, chromium-, aluminium- titanium- zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese-, gold- and iron- containing alloys, and super-alloys based on nickel, iron, cobalt, stainless steel, Timetai® and iron-manganese-aluminium based alloys. In composite materials, the electrically resistive material may optionally be embedded in, encapsulated or coated with an insulating material or vice-versa, depending on the kinetics of energy transfer and the external physicochemical properties required.

As described, in any of the aspects of the disclosure, the heating element may be part of an aerosol-generating device. The aerosol-generating device may comprise an internal heating element or an external heating element, or both internal and external heating elements, where "internal" and "external" refer to the aerosol-forming substrate. An internal heating element may take any suitable form. For example, an internal heating element may take the form of a heating blade. Alternatively, the internal heater may take the form of a casing or substrate having different electro-conductive portions, or an electrically resistive metallic tube. Alternatively, the internal heating element may be one or more heating needles or rods that run through the center of the aerosolforming substrate. Other alternatives include a heating wire or filament, for example a Ni-Cr (Nickel-Chromium), platinum, tungsten or alloy wire or a heating plate. Optionally, the internal heating element may be deposited in or on a rigid carrier material. In one such embodiment, the electrically resistive heating element may be formed using a metal having a defined relationship between temperature and resistivity. In such an exemplary device, the metal may be formed as a track on a suitable insulating material, such as ceramic material, and then sandwiched in another insulating material, such as a glass. Heaters formed in this manner may be used to both heat and monitor the temperature of the heating elements during operation.

An external heating element may take any suitable form. For example, an external heating element may take the form of one or more flexible heating foils on a dielectric substrate, such as polyimide. The flexible heating foils can be shaped to conform to the perimeter of the substrate receiving cavity. Alternatively, an external heating element may take the form of a metallic grid or grids, a flexible printed circuit board, a molded interconnect device (MID), ceramic heater, flexible carbon fibre heater or may be formed using a coating technique, such as plasma vapour deposition, on a suitable shaped substrate. An external heating element may also be formed using a metal having a defined relationship between temperature and resistivity. In such an exemplary device, the metal may be formed as a track between two layers of suitable insulating materials. An external heating element formed in this manner may be used to both heat and monitor the temperature of the external heating element during operation.

As an alternative to an electrically resistive heating element, the heating element may be configured as an induction heating element. The induction heating element may comprise an induction coil and a susceptor. In general, a susceptor is a material that is capable of generating heat, when penetrated by an alternating magnetic field. When located in an alternating magnetic field. If the susceptor is conductive, then typically eddy currents are induced by the alternating magnetic field. If the susceptor is magnetic, then typically another effect that contributes to the heating is commonly referred to hysteresis losses. Hysteresis losses occur mainly due to the movement of the magnetic domain blocks within the susceptor, because the magnetic orientation of these will align with the magnetic induction field, which alternates. Another effect contributing to the hysteresis loss is when the magnetic domains will grow or shrink within the susceptor. Commonly all these changes in the susceptor that happen on a nano-scale or below are referred to as “hysteresis losses”, because they produce heat in the susceptor. Hence, if the susceptor is both magnetic and electrically conductive, both hysteresis losses and the generation of eddy currents will contribute to the heating of the susceptor. If the susceptor is magnetic, but not conductive, then hysteresis losses will be the only means by which the susceptor will heat, when penetrated by an alternating magnetic field. According to the invention, the susceptor may be electrically conductive or magnetic or both electrically conductive and magnetic. An alternating magnetic field generated by one or several induction coils heat the susceptor, which then transfers the heat to the aerosol-forming substrate, such that an aerosol is formed. The heat transfer may be mainly by conduction of heat. Such a transfer of heat is best, if the susceptor is in close thermal contact with the aerosol-forming substrate.

As used herein, the term ‘aerosol-generating article’ refers to an article comprising an aerosol-forming substrate that is capable of releasing volatile compounds that can form an aerosol. The aerosol-forming substrate may be part of the substrate portion. For example, an aerosol-generating article may be a smoking article that generates an aerosol that is directly inhalable into a user’s lungs through the user's mouth. An aerosol-generating article may be disposable.

The aerosol-generating article may comprise at least the substrate portion and the mouthpiece portion as described herein.

As used herein, the term ‘aerosol-forming substrate’ relates to a substrate capable of releasing one or more volatile compounds that can form an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. An aerosol-forming substrate may conveniently be part of an aerosol-generating article or smoking article.

The aerosol-forming substrate may be a solid aerosol-forming substrate. The aerosolforming substrate may comprise both solid and liquid components. The aerosol-forming substrate may comprise a tobacco-containing material containing volatile tobacco flavour compounds which are released from the substrate upon heating. The aerosol-forming substrate may comprise a non-tobacco material. The aerosol-forming substrate may comprise an aerosol former that facilitates the formation of a dense and stable aerosol. Examples of suitable aerosol formers are glycerine and propylene glycol.

The aerosol-generating substrate preferably comprises homogenised tobacco material, an aerosol-former and water. Providing homogenised tobacco material may improve aerosol generation, the nicotine content and the flavour profile of the aerosol generated during heating of the aerosol-generating article. Specifically, the process of making homogenised tobacco involves grinding tobacco leaf, which more effectively enables the release of nicotine and flavours upon heating. 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.

Example ex1. An aerosol-generating article comprising a mouthpiece portion, wherein the mouthpiece portion is hollow and cylindrical, wherein the mouthpiece portion comprises a sheet, wherein the sheet is arranged one or both of in the mouthpiece portion and forming an inner sidewall of the mouthpiece portion, wherein the sheet comprises protrusions extending at an angle from the sheet.

Example ex2. The aerosol-generating article according to example ex1, wherein the aerosol-generating article further comprises a substrate portion upstream of the mouthpiece portion.

Example ex3. The aerosol-generating article according to any of the preceding examples, wherein the sheet is folded and arranged in the mouthpiece portion.

Example ex4. The aerosol-generating article according to example ex3, wherein the sheet is folded at least 2 times, preferably at least 3 times, more preferably at least 4 times.

Example ex5. The aerosol-generating article according to any of the preceding examples, wherein the sheet has a length of between 2 and 6 times an inner diameter of the mouthpiece portion, preferably of between 3 and 5 times the inner diameter of the mouthpiece portion, more preferably of 4 times the inner diameter of the mouthpiece portion.

Example ex6. The aerosol-generating article according to any of the preceding examples, wherein an extension plane of the sheet is parallel to a longitudinal axis of the aerosol-generating article.

Example ex7. The aerosol-generating article according to any of the preceding examples, wherein the sheet has a thickness of between 50 micrometres and 1000 micrometres, preferably between 200 micrometres and 500 micrometres.

Example ex8. The aerosol-generating article according to any of the preceding examples, wherein the sheet is wound to form an innermost layer of the mouthpiece portion.

Example ex9. The aerosol-generating article according to example ex8, wherein the protrusions extend radially inwards from the innermost layer of the mouthpiece portion.

Example ex10. The aerosol-generating article according to example ex2 and ex9, wherein the protrusions extend radially inwards to obstruct a view of the substrate portion from the open end of the mouthpiece portion.

Example ex11. The aerosol-generating article according to any of the preceding examples, wherein the mouthpiece portion has an open downstream end. Example ex12. The aerosol-generating article according to any of the preceding examples, wherein axial gaps are arranged between the individual protrusions to enable airflow through the protrusions.

Example ex13. The aerosol-generating article according to any of the preceding examples, wherein the protrusions are arranged to prevent or reduce unwanted residues or aerosol-forming substrate from the substrate portion of example ex2 from falling through the protrusions.

Example ex14. The aerosol-generating article according to any of the preceding examples, wherein the sheet comprises cardboard, preferably wherein the sheet is made from cardboard.

Example ex15. The aerosol-generating article according to any of the preceding examples, wherein the sheet is spirally wound to form the innermost layer of the mouthpiece portion.

Example ex16. The aerosol-generating article according to example ex15, wherein the sheet is overlappingly spirally wound to form the innermost layer of the mouthpiece portion.

Example ex17. The aerosol-generating article according to example ex16, wherein the portion of the sheet being overlapped during winding is coated with an adhesive.

Example ex18. The aerosol-generating article according to any of the preceding examples, wherein the sheet comprises at least a first sheet and an overlapping second sheet, and wherein one or both of the first sheet and the second sheet comprise the protrusions.

Example ex19. The aerosol-generating article according to example ex18, wherein the sheet comprises at least a third sheet and a fourth sheet, and wherein one or more of the first sheet, the second sheet, the third sheet and the fourth sheet overlap.

Example ex20. The aerosol-generating article according to any of the preceding examples, wherein the protrusions have an extension direction perpendicular to a longitudinal axis of the aerosol-generating article.

Example ex21. The aerosol-generating article according to any of the preceding examples, wherein the protrusions have a triangular, rectangular, disc, teardrop or bristle shape.

Example ex22. The aerosol-generating article according to any of the preceding examples, wherein the protrusions are formed integrally with the sheet.

Example ex23. The aerosol-generating article according to any of examples ex1 to ex21, wherein the protrusions are attached to the sheet, preferably wherein the protrusions are attached to the sheet with an elastic adhesive. Example ex24. The aerosol-generating article according to any of the preceding examples, wherein one or both of the sheet and the protrusions comprise, preferably consists of, one or more of fibers, threads and yarn.

Example ex25. The aerosol-generating article according to any of the preceding examples, wherein one or both of the sheet and the protrusions comprise, preferably consists of, cellulose, cellulose pulp derived from wood, cotton, rice, lignocellulosic materials, paper, wool, cotton, silk, linen, raffia, coconut, bamboo or jute.

Example ex26. The aerosol-generating article according to any of the preceding examples, wherein the protrusions are formed along a long side edge of the sheet.

Example ex27. The aerosol-generating article according to example ex26, wherein the adhesive layer of example ex17 is coated on a portion of the sheet opposite to the long side edge at which the protrusions are formed.

Example ex28. The aerosol-generating article according to any of the preceding examples, wherein the protrusions comprise a coating.

Example ex29. The aerosol-generating article according to example ex28, wherein the coating is configured to trap one or both of phenols and flu gases or wherein the coating comprises a flavourant.

Example ex30. A method for forming a mouthpiece portion of an aerosolgenerating article, the method comprising the following steps: providing a sheet comprising protrusions;

- wrapping the sheet around a mandrel thereby forming an innermost layer of a hollow cylindrical mouthpiece portion or arranging the sheet in the mouthpiece portion; and extending the protrusions in an angled direction with respect to the sheet.

Example ex31. The method of example ex30, wherein the method comprises, before wrapping of the sheet, folding of the protrusions against the sheet.

Example ex32. The method of example ex31 , wherein the protrusions are configured to automatically unfold after removal of the wrapped sheet from the mandrel.

Features described in relation to one embodiment may equally be applied to other embodiments of the invention.

The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 shows an aerosol-generating article according to the invention;

Fig. 2 shows a wrapping of a sheet of the aerosol-generating article; Fig. 3 shows a further embodiment of the wrapping of the sheet of the aerosolgenerating article;

Fig. 4 shows a further embodiment of the wrapping of the sheet of the aerosolgenerating article;

Figs. 5A to 5E show cross-sectional views of different wrapping techniques;

Figs. 6A to 6F show cross-sectional views of the embodiments of the sheet having protrusions;

Fig. 7 shows an embodiment of the sheet of the aerosol-generating article;

Fig. 8 shows a wrapping action of the sheet of Figure 7;

Fig. 9 shows a cross-sectional view of unfolded protrusions;

Fig. 10 shows a side view of the unfolded protrusions;

Figs. 11 A and 11 B show a further embodiment of the sheet having protrusions;

Fig. 12 shows a wrapping action of the sheet of Figure 11 ;

Figs. 13A and 13B show a further embodiment of the protrusions of the sheet;

Fig. 14 shows a further embodiment in which the sheet is placed inside a hollow cylindrical mouthpiece portion of the aerosol-generating article;

Fig. 15 shows a cross-sectional view of a configuration of protrusions of the sheet;

Fig. 16 shows a cross-sectional side view of the protrusions of Figure 15;

Figs. 17A and 17B show configurations of the sheet of Figures 15 and 16 before being folded;

Fig. 18 shows a further configuration of the protrusions;

Figs. 19A to 19C show further configurations of the protrusions;

Figure 1 shows an aerosol-generating article 10. The aerosol-generating article 10 comprises a mouthpiece portion 12. The mouthpiece portion 12 is hollow and cylindrical. Figure 1 further shows a substrate portion 14 of the aerosol-generating article 10. The substrate portion 14 comprises aerosol-forming substrate.

Figure 1 further shows a further portion of the aerosol-generating article 10. The further portion preferably is a cooling portion 16. The cooling portion 16 may comprise perforations (not shown) to enable ambient air to be drawn into the aerosol-generating article 10 to be mixed with air drawn through the aerosol-generating article 10. The perforations may be provided in the sidewall of the cooling portion 16. The mixing of ambient air with the air being drawn through the aerosol-generating article 10 may enable aerosol formation in the cooling portion 16 due to a condensation of vaporized aerosol-forming substrate and therefore the formation of small droplets of vaporized aerosol-forming substrate. The aerosol is subsequently drawn through the mouthpiece portion 12 into the mouth of a user. Figure 1 finally shows a front plug 18. The front plug 18 may comprise a filter element such as an acetate tow filter element. The front plug 18 may prevent aerosol-forming substrate from falling out of an upstream end 20 of the aerosol-generating article 10. The front plug 18 is preferably the most upstream portion of the aerosol-generating article 10. In other words, the front plug 18 is arranged at the upstream end 20 of the aerosol-generating article 10. This may also be referred to as a distal end or distal portion of the aerosolgenerating article 10.

Downstream or proximal of the front plug 18, the substrate portion 14 is arranged. As mentioned, the substrate portion 14 contains the aerosol-forming substrate. The substrate portion 14 may also be denoted as sensorial media portion and the aerosol-forming substrate may also be denoted as sensorial media. The aerosol-forming substrate is configured to be vaporized by a heating action of an aerosol-generating device. The aerosol-generating device is not shown in Figure 1 but may comprise a cavity for receiving the aerosolgenerating article 10 and a heating element arranged at least partly around the cavity for heating the substrate portion 14 of the aerosol-generating article 10.

Downstream or proximal of the substrate portion 14, the cooling portion 16 of the aerosol-generating article 10 is arranged. Downstream or proximal of the cooling portion 16, the mouthpiece portion 12 is arranged. The mouthpiece portion 12 may thus be the most downstream or proximal portion of the aerosol-generating article 10. In other words, the mouthpiece portion 12 may be arranged at a downstream end 22 or proximal end of the aerosol-generating article 10.

In use, a user may directly contact the mouthpiece portion 12 with his or her lips and draw air through the aerosol-generating article 10. As mentioned, ambient air may additionally be drawn into the aerosol-generating article 10 through perforations of the cooling portion 16.

Figure 2 shows a sheet 24 of the aerosol-generating article 10. Figures 2 to 13 show a first main embodiment of the present disclosure in which the sheet 24 forms an innermost sidewall of the hollow cylindrical mouthpiece portion 12 of the aerosol-generating article 10. Figures 14 to 19 show a main second embodiment of the present disclosure in which the sheet 24 is arranged inside of the hollow cylindrical mouthpiece portion 12. However, it should be noted that these embodiments could be combined. Exemplarily, the innermost layer of the mouthpiece portion 12 may be formed with a sheet 24 according to any of Figures 2 to 13 and, additionally or alternatively, a sheet 24 may be arranged inside of the inner hollow mouthpiece portion 12 is shown at any of Figures 14 to 19.

Figure 2 shows a manufacturing step of the mouthpiece portion 12 of the aerosolgenerating article 10. In this manufacturing step, the sheet 24 is wound around a mandrel 26. The winding action of the sheet 24 around the mandrel 26 forms a hollow cylindrical tube. In the embodiment shown in Figure 2, the individual layers of the sheet 24 are wound around a mandrel 26 so as to be arranged next to each other. In other words, the sheet 24 does not overlap.

The hollow cylindrical tube may then be removed from the mandrel 26 so as to form the hollow cylindrical mouthpiece portion 12. The hollow cylindrical tube may be cut in a radial direction to form individual mouthpiece portion 12s for individual aerosol-generating article 10.

Figure 3 shows a different option of winding the sheet 24 around the mandrel 26. In this variation, the sheet 24 is overlappingly wound around the mandrel 26. Figure 3 shows an overlapping area of the sheet 24. The overlapping area may be coated with an adhesive 28 to facilitate a secure attachment between overlapping areas of the sheet 24.

Figure 4 shows yet another option of creating the innermost layer of the mouthpiece portion 12 by winding the sheet 24 around the mandrel 26. In the embodiment shown in Figure 4, instead of a single sheet 24 as shown in Figures 2 and 3, multiple sheets 24 are used during the wrapping. In the specific embodiment shown in Figure 4, four individual sheets 24 are wrapped around the mandrel 26. Sheets 24 overlap with each other. More specifically, the first sheet 32 overlaps with the second sheet 34, the second sheet 34 overlaps with the third sheet 36 and the third sheet 36 overlaps with the fourth sheet 38. It should be noted that the specific number of four sheets 24 is only illustrative. If desired, two, three, four or more than four sheets 24 could be used for the creation of the innermost layer of the mouthpiece portion 12. Additionally, it should be appreciated that these sheets 24 could be arranged in an overlapping manner so that one or more of the sheets 24 overlap. Alternatively, the streets could be arranged next to each other similar to the arrangement of the single sheet 24 of Figure 2.

Figures 5A to 5E show different wrapped configurations of the sheet 24 or of the sheets 24. All of these Figures show a cross-sectional view of the sheet 24 or of the sheets 24 after the wrapping action. Figure 5A shows a wrapped configuration of the single sheet 24 similar to the wrapping action shown in Figure 2. In this embodiment, the sheet 24 is wrapped so that the individual layers of the sheet 24 abut each other but do not overlap with each other. Figure 5B shows a wrapped configuration in which at least two and preferably four sheets 24 as shown in Figure 4 are wrapped so as to overlap. Figure 5C shows a wrapped sheet 24 so that the sheet 24 overlaps. This could be done with a single sheet 24 as shown in Figure 3. Alternatively, two sheets 24 could be utilized so as to overlap. Figure 5D also shows an overlapping between sheets 24. The overlapping is such that a straight inner surface is created. In other words, the inner surface is parallel to a longitudinal axis of the aerosol-generating article 10. Again in other words, the sheet 24 may be overlap such as to create a tile-like configuration. Similarly, the outer surface that is created is also straight so as to be parallel to a longitudinal axis of the aerosol-generating article 10. This may be facilitated by applying pressure to the sheet 24 being wound as shown in Figure 5C. The pressure may be created by a tension of the sheet 24 during the wrapping action. Alternatively or additionally, the sheet 24 may be made from an elastic material or deformable material such that the sheet 24 in the overlapping area conforms to the shape of the mandrel 26 as shown in Figure 5D. Finally, Figure 5E shows a wrapped configuration of the sheet 24 with preferably four layers of the sheet 24. The two innermost layer’s overlap similarly to the overlapping action shown in Figure 5D. The two outermost layer’s overlap similarly to the overlapping shown in Figure 5B. It should be noted that, in the embodiment shown in Figures 5A, 5C and 5D, the sheet 24 the realized by a single sheet 24 or by multiple sheets 24. The embodiments shown in Figures 5B and 5E are preferably always facilitated by at least two sheets 24.

Figure 6 shows different configurations of protrusions 40 of the sheet 24. Figure 6A shows protrusions 40 integrally formed with the sheet 24. In Figure 6A, the protrusions 40 are folded against the sheet 24. This arrangement of the protrusions 40 is preferred during the manufacturing step of the sheet 24. In other words, this arrangement of the protrusions 40 is preferred when the sheet 24 is wound around the mandrel 26. After this manufacturing step, the protrusions 40 unfold as shown in Figure 6B. In other words, after the sheet 24 is removed from the mandrel 26, the protrusions 40 unfold. As shown in Figure 6B, the protrusions 40 are angled in a direction that is angled with respect to an extension plane of the sheet 24. The protrusions 40 are angled with respect to a longitudinal axis of the aerosolgenerating article 10. Particularly preferred, the protrusions 40 unfolded in a direction essentially perpendicular to the longitudinal axis of the aerosol-generating article 10. The unfolding of the protrusions 40 preferably happens automatically. Particularly preferred, the protrusions 40 are made from an elastic material such that the protrusions 40 unfold after removing the wound sheet 24 from the mandrel 26.

Figure 6C shows a different configuration of the protrusions 40. In this embodiment, the protrusions 40 are configured as bristles. Differing from the configuration from Figures 6A and Figure 6B, the protrusions 40 of Figures 6C and 6D are not integrally formed with the sheet 24. Instead, the bristles are attached to the sheet 24. This may be done by for example by an adhesive 28. In Figure 6C, the protrusions 40 are folded against the sheet 24 so as to enable a winding of the sheet 24 around the mandrel 26. In Figure 6D, the bristles unfold similar to the protrusions 40 shown in Figure 6B. This may be done automatically by the elastic nature of the adhesive 28 and/or the elastic nature of the bristles. Finally, Figure 6E and Figure 6F show another option of protrusions 40. In the embodiment shown in Figure 6E and 6F, the protrusions 40 are not integrally formed with the sheet 24. Instead, the protrusions 40 are attached to the sheet 24 by means of an elastic connection 42. The elastic connection 42 may be configured as an elastic adhesive 28. In Figure 6F, the protrusions 40 are folded against the sheet 24 to enable a winding of the sheet 24 around the mandrel 26. In Figure 6E, the protrusions 40 are in an unfolded state before the winding of the sheet 24 around the mandrel 26. A partly unfolding of the protrusions 40 similar to Figure 6B and 6D is not shown in Figure 6E and 6F. After removing the sheet 24 from the mandrel 26, the protrusions 40 of Figure 6E and 6F may unfold in an angled direction with respect to an extension plane of the sheet 24. The protrusions 40 of Figure 6E and 6F may be made from fiber or yarn. This material is biodegradable. In all of the herein described embodiments, the sheet 24 itself may be made from cardboard.

Figure 7 shows the configuration of the sheet 24 with triangular protrusions 40. This type of protrusions 40 may exemplarily also be referred to as flaps. Other flap-like protrusions 40 are shown for example in Figure 19. The protrusions 40 in this and potentially in all other embodiments may be arranged abutting a long side of the sheet 24. The protrusions 40 may be arranged on an opposite side to a side on which adhesive 28 is applied and which is utilized for overlapping during the winding of the sheet 24.

Figure 8 shows the sheet 24 of Figure 7 being wound around the mandrel 26. The protrusions 40 are in a folded configuration so as to be pressed against the mandrel 26 during the winding action. After the winding action, the sheet 24 is removed from the mandrel 26 so that the protrusions 40 can unfold.

Figure 9 shows the protrusions 40 of the sheet 24 of Figure 7 and 8 in an unfolded state. As shown in Figure 9, the protrusions 40 unfold in a radially inwards direction. As a consequence, the protrusions 40 at least partially block the hollow inner of the mouthpiece portion 12. The blocking action may be such that air can freely flow through the mouthpiece portion 12. However, loose unwanted particles from the aerosol-forming substrate of the substrate portion 14 of the aerosol-generating article 10 may be prevented from falling out of the mouthpiece portion 12 in a downstream direction. At the same time, an unobstructed view through the hollow inner cylindrical mouthpiece portion 12 may be prevented by the unfolded protrusions 40.

Figure 10 shows the same configuration shown in Figure 9 from a different perspective. In this perspective, it can be seen that the spiral winding of the she leads to a spiral arrangement of the protrusions 40. As such, the protrusions 40 enable airflow through the hollow inner of the mouthpiece portion 12 while obstructing the view of the substrate portion 14 and preventing unwanted residues from the aerosol-forming substrate from falling out of the mouthpiece portion 12.

Figures 11A and 11 B show the unfolded protrusions 40 similar to the configuration of Figure 6E and Figure 11 B shows the folded protrusions 40 similar to the protrusions 40 as shown in Figure 6F.

Figure 12 shows an arrangement of the protrusions 40 configured as bristles during the winding action of the sheet 24 around the mandrel 26. The configuration of the protrusions 40 is similar to the configuration of the protrusions 40 shown in Figure 6C and 6D. As shown in Figure 12, the bristles may be pressed against the sheet 24 only due to the winding action of the sheet 24 around the mandrel 26. Before and after the winding action, the bristles may be an unfolded state.

Figures 13A and 13B show a further embodiment of the protrusions 40. In this embodiment, the protrusions 40 are configured as one or both of hooks and loop similar to the configurations of the elements of a Velcro closure. This may particularly beneficial to filter unwanted residues from the aerosol being drawn through the mouthpiece portion 12. In other words, this configuration of the protrusions 40 may result in a filtering action of the air being drawn through the mouthpiece portion 12.

Figure 14 shows a second main embodiment of the present invention in which the sheet 24 is folded and placed inside of the hollow cylindrical mouthpiece portion 12. In this embodiment, the innermost layer of the mouthpiece portion 12 may be formed as shown in Figures 2 to 13 or may alternatively be formed in a different conventional manner. In other words, the innermost layer of the mouthpiece portion 12 may be configured as a sheet 24 as described herein or in a different conventional manner. The folded sheet 24 being placed inside of the inner hollow cylindrical mouthpiece portion 12 may have a similar function as the sheet 24 described in conjunction with Figures 2 to 13. Particularly, the sheet 24 may prevent an unobstructed view of the substrate portion 14 of the aerosol-generating article 10 through the inner hollow mouthpiece portion 12. Further, the sheet 24 may prevent unwanted particle residues from the aerosol-forming substrate of the substrate portion 14 to fall out of the hollow cylindrical mouthpiece portion 12. As shown in Figure 14, the sheet 24 may be forwarded in an “Omega” configuration. The sheet 24 may be folded at least 2, preferably at least 3, preferably at least 4, most preferably at least at least 5 times.

Figure 15 shows a configuration of the sheet 24 having protrusions 40. The protrusions 40 extend at an angle direction with respect to the extension of the sheet 24. Due to the folding action of the sheet 24, the protrusions 40 extend within the inner hollow mouthpiece portion 12. The extension direction of the protrusions 40 is particularly preferred perpendicular to a longitudinal axis of the aerosol-generating article 10. Similarly, the sheet 24 is preferably folded in a direction parallel to the longitudinal axis of the aerosol-forming article such that a width direction of the sheet 24 is also parallel to the longitudinal axis of the aerosol-generating article 10 whereas a length direction of the sheet 24 is perpendicular to the longitudinal axis of the aerosol-generating article 10. A radial direction perpendicular to the longitudinal axis of the aerosol-generating article 10 is indicated by the line A -A’ in Figure 15.

Figure 16 shows the same arrangement of the sheet 24 as shown in Figure 15 from a cross-sectional side view. As can be seen, a width direction of the sheet 24 extends parallel to the longitudinal axis of the aerosol-generating article 10 and parallel to a flow direction of the aerosol being drawn through the mouthpiece portion 12. The direction of the aerosol flow is indicated by the dashed line. The angled extension of the protrusions 40 with respect to the sheet 24 is indicated by the angle A. In embodiments described herein, the angle may be larger than 20°, preferably larger than 30°, for more preferably larger than 40°, most preferably larger than 50°.

Figures 17A and 17B show a potential configuration of the sheet 24 employed in Figures 15 and 16. In this configuration, a portion of the sheet 24 adjacent a centerline 44 of the sheet 24 is provided with the protrusions 40. A portion of the sheet 24 adjacent the long ends of the sheet 24 is configured as a protrusion-free portion 46. After the folding of the sheet 24 and the insertion of the sheet 24 into the hollow inner of the mouthpiece portion 12, the protrusion-free portion 46 of the sheet 24 is arranged adjacent, preferably abutting, the inner side wall of the mouthpiece portion 12. The portion of the sheet 24 comprising the protrusions 40 is arranged inside of the mouthpiece portion 12 as shown in Figure 15 and Figure 16 so that the protrusions 40 extend in the inner of the mouthpiece portion 12 perpendicular to the longitudinal axis of the aerosol-generating article 10. Figure 17A shows an opposite side of the sheet. The protrusion-free portion 46 of the upper side may face the inside of the mouthpiece portion 12 after the folding action. Hence, the protrusion-free portion 46 of the upper side may in fact be provided with protrusions 40 is shown in Figure 15. However, the bottom side of the sheet 24 shown in Figure 17B may indeed feature the protrusion-free portion 46 as this portion is abutting the inner sidewall of the mouthpiece portion 12 after the folding action.

Figure 18 shows a different embodiment of creating the protrusions 40. Instead of the protrusions 40 being configured as bristles or similar protrusions 40, the protrusions 40 of Figure 18 are configured as flaps. These flaps are integrally formed with the sheet 24 and may be stamped out or cut out of the sheet 24 as shown in Figure 18.

Figures 19A to 19C show configurations of the protrusions 40. Figure 19A shows rectangular protrusions 40 that may be created by the sheet 24 as shown in Figure 18. Figure 19B shows circular protrusions 40 which may be created in a similar way as the protrusions 40 shown in Figure 18. In difference to the protrusions 40 shown in Figure 18, the circular protrusions 40 would have to be cut in a circular manner. Figure 19C show configurations of the protrusions 40 such that the protrusions 40 cover most of the cross- sectional surface of the hollow inner of the mouthpiece portion 12. These protrusions 40 have a teardrop shape. Similarly to the protrusions 40 shown in Figures 18, 19A and 19B, these teardrop shaped protrusions 40 may be created by cutting or stamping out respective portions from the sheet 24.

Claims

1. An aerosol-generating article comprising a mouthpiece portion, wherein the mouthpiece portion is hollow and cylindrical, wherein the mouthpiece portion comprises a sheet, wherein the sheet is arranged one or both of in the mouthpiece portion and forming an inner sidewall of the mouthpiece portion, wherein the sheet comprises protrusions extending at an angle from the sheet.

2. The aerosol-generating article according to claim 1, wherein the aerosolgenerating article further comprises a substrate portion upstream of the mouthpiece portion.

3. The aerosol-generating article according to any of the preceding claims, wherein the sheet is folded and arranged in the mouthpiece portion.

4. The aerosol-generating article according to any of the preceding claims, wherein an extension plane of the sheet is parallel to a longitudinal axis of the aerosolgenerating article.

5. The aerosol-generating article according to any of the preceding claims, wherein the sheet is wound to form an innermost layer of the mouthpiece portion.

6. The aerosol-generating article according to claim 5, wherein the protrusions extend radially inwards from the innermost layer of the mouthpiece portion.

7. The aerosol-generating article according to any of the preceding claims, wherein axial gaps are arranged between the individual protrusions to enable airflow through the protrusions.

8. The aerosol-generating article according to any of the preceding claims, wherein the sheet comprises cardboard, preferably wherein the sheet is made from cardboard.

9. The aerosol-generating article according to any of the preceding claims, wherein the sheet is spirally wound to form the innermost layer of the mouthpiece portion.

10. The aerosol-generating article according to claim 9, wherein the sheet is overlappingly spirally wound to form the innermost layer of the mouthpiece portion.

11. The aerosol-generating article according to claim 10, wherein the portion of the sheet being overlapped during winding is coated with an adhesive.

12. The aerosol-generating article according to any of the preceding claims, wherein the sheet comprises at least a first sheet and an overlapping second sheet, and wherein one or both of the first sheet and the second sheet comprise the protrusions.

13. The aerosol-generating article according to any of the preceding claims, wherein the protrusions have an extension direction perpendicular to a longitudinal axis of the aerosol-generating article.

14. The aerosol-generating article according to any of the preceding claims, wherein the protrusions have a triangular, rectangular, disc, teardrop or bristle shape.

15. A method for forming a mouthpiece portion of an aerosol-generating article, the method comprising the following steps: providing a sheet comprising protrusions;