WO2023161411A1

WO2023161411A1 - An aerosol generating article comprising impregnated charcoal paper filter and a flavoring capsule

Info

Publication number: WO2023161411A1
Application number: PCT/EP2023/054666
Authority: WO
Inventors: Takuya OTOKAWA; Ahmad LISAN
Original assignee: Jt International S.A.
Priority date: 2022-02-25
Filing date: 2023-02-24
Publication date: 2023-08-31

Abstract

The present invention concerns a filter (45) for an aerosol generating article, the filter (45) extending along a filter axis (F) between an upstream end (55) and a mouth end (60). The upstream end (55) is configured to be in fluid communication with a downstream end of an aerosol generating substrate. The filter (45) comprises an upstream end filter portion (70) delimiting the upstream end (55) and comprising impregnated charcoal paper or nonwoven substrate (83), and a mouth end filter portion (65) delimiting the mouth end (60) The filter further comprises at least one flavouring capsule (82).

Description

An aerosol generating article comprising impregnated charcoal paper filter and a flavoring capsule

FIELD OF THE INVENTION

The present invention concerns a filter for an aerosol generating article, comprising charcoal. The invention also concerns an aerosol generating article for aerosol generation devices comprising such a filter.

Particularly, the aerosol generating article according to the invention is configured to operate with an aerosol generating device, also known as a heat-not-burn device or HNB device. Such type of aerosol generating devices is adapted to heat, rather than burn, an aerosol generating substrate comprised in the article.

BACKGROUND OF THE INVENTION

The popularity and use of reduced-risk or modified-risk devices (also known as vaporizers or aerosol generating devices) has grown rapidly in the past few years as an aid to assist habitual smokers wishing to quit smoking traditional tobacco products such as cigarettes, cigars, cigarillos, and rolling tobacco. Various devices and systems are available that heat or warm vaporizable substances as opposed to burning tobacco in conventional tobacco products.

A commonly available reduced-risk or modified-risk device is an electrically heated substrate aerosol generation device or heat-not-burn device, also known as HNB device. Devices of this type generate aerosol or vapour by heating an aerosol generating substrate that typically comprises moist leaf tobacco or other suitable vaporizable material to a temperature typically below the temperature of combustion of tobacco but sufficient to produce vapour and/or release volatiles that condense to form an aerosol. Heating an aerosol generating substrate, but not combusting or burning it, releases aerosol that comprises the components sought by the user but not the toxic and carcinogenic byproducts of combustion and burning. Furthermore, the aerosol produced by heating the tobacco or other vaporizable material does not typically comprise the burnt or bitter taste resulting from combustion and burning that can be unpleasant for the user and so the substrate does not therefore require the sugars and other additives that are typically added to such materials to make the smoke and/or vapour more palatable for the user. Aerosol generating articles used generally with HNB devices comprise an aerosol generating substrate and a filter. While using an HNB device, the filter may be in contact with the mouth and/or lips of the user. Thus, when the user inhales, aerosol generated by the aerosol generating substrate passes through the filter where it is cooled and its pressure and taste intensity are reduced. Generally, as for conventional cigarettes, the filter can be made of cellulose acetate fiber. However, such aerosol generating articles with cellulose acetate filters provide high resistance to puffing due to relatively compact fiber tow. Additionally, aerosol generating articles with cellulose acetate filters tend to reduce flavor taste intensity as a certain amount of desirable flavoring volatiles may remained trapped in the filter. Decreasing cellulose acetate filter resistance may cause manufacturability issues.

As a response, it is known to introduce a flavoring capsule in a filter of the aerosol generating article. When the flavour is released, such as by breaking the capsule’s shell on demand, the flavour is carried out by the aerosol to the mouth end. The taste of the aerosol is thus modified by the addition of flavour molecules carried out in the aerosol. However, the flavoring capsule also increases the pressure drop that deteriorates the user experience.

Aerosol generating articles may also deliver harsh taste due to tobacco and/or nicotine contained in the aerosol generating substrate. Such taste may negatively affect the taste of the flavour of the filter modulating the taste of the substrate.

Therefore, a need exists for a filter and an aerosol generating articles for HNB device that improves risk-reduction, improve sensory impact by enhancing flavour taste while maintaining mild and/or smooth taste, and reduce puff resistance.

SUMMARY OF THE INVENTION

One aim of the invention is to provide a filter for an aerosol generating article designed to be used with an HNB device providing a better user experience.

For this purpose, the invention relates to a filter for an aerosol generating article, the filter extending along a filter axis between an upstream end and a mouth end, the upstream end being configured to be in fluid communication with a downstream end of an aerosol generating substrate; the filter comprising:

- an upstream end filter portion delimiting the upstream end and comprising impregnated charcoal paper or a nonwoven substrate;

- a mouth end filter portion delimiting the mouth end;

- at least one flavouring capsule.

With the filter according to the invention, the taste of the aerosol generating substance, in particular the tobacco taste can be smoothened or made milder so as to enhance taste of the flavour added by the filter. At the same time, the puff resistance remains acceptable or may even be reduced due to the low pressure drop of the charcoal paper or nonwoven filter.

With the impregnated charcoal paper or nonwoven, when the user inhales, aerosol generated by the aerosol generating substrate passes through the filter wherein it is in contact with charcoal before reaching the user’s mouth. During such contact, the charcoal modify the taste of the aerosol by smoothening it and making it milder.

Impregnated charcoal paper or nonwoven substrate refers to a paper sheet made of natural cellulose or a nonwoven sheet comprising fine charcoal particles bonded to or fixed in the substrate of the sheet before the gathering or rolling of the sheet to form the filter rod. Impregnated charcoal paper differs from standard paper filter comprising a mixture of loose charcoal particles or granules. In a loose configuration, charcoal particles or granules are dispersed throughout the paper during filter rod making process and the density of paper filter must be increased to maintain the desired distribution of charcoal within the filter.

In the following description, the term “nonwoven substrate” refers to nonwoven sheet comprising natural fibres and a binder. The natural fibres preferably comprise or preferably consist of wood pulp, the wood pulp preferably being obtained by a kraft process. The natural fibers (without considering charcoal content) preferably represent 85% to 95% by weight of the nonwoven substrate, and the binder represents 5 to 15% by weight of the nonwoven substrate, wherein the nonwoven substrate has a dry tensile strength of at least 10 N/5cm, preferably at least 12 N/5cm and most preferably at least 14 N/5cm, and the nonwoven substrate has a thickness from 0.4 to 1 .0 mm, preferably from 0.5 to 0.9mm, and most preferably from 0.5 to 0.7 mm. The natural fibers (without considering charcoal content) preferably represent from 90 to 93% by weight of the nonwoven substrate, and/or the binder represents from 7 to 10% by weight of the nonwoven substrate. The nonwoven substrate (without charcoal) preferably has a volume density of at least 50 mg/cm³, preferably of at least 55 mg/cm³ and most preferably of at least 60 mg/cm ³, and/or a volume density of at most 1 10 mg/cm³, preferably of at most 100 mg/cm³ and most preferably of at most 90 mg/cm³. The nonwoven substrate has preferably an areal density from 40 to 65 mg/cm², preferably from 45 to 60 mg/cm², most preferably from 45 to 55 mg/cm², and even most preferably from 45 to 50 mg/cm². The average length of the natural fibers is preferably at most 3.5 mm, preferably at most 3.0 mm and most preferably at most 2.8 mm, and/or the average length of the natural fibers is at least 2.0 mm, preferably at least 2.3 mm and most preferably at least 2.5 mm. The binder preferably comprises at least one binding agent being a water-based polymer emulsion, preferably solvable in water. The binder may comprise one or more of an aqueous copolymer dispersion of Ethylene Vinyl Acetate, EVA, and a Polyvinyl Acetate, PVAc, adhesive. The nonwoven substrate may be crimped in the machine direction with a crimping depth of 0.2 to 1.0 mm, preferably of 0.5 to 0.9 mm. A nonwoven substrate without charcoal impregnation is described in co-pending European patent application No. 22210227.

The manufacturing of the impregnated charcoal paper may comprise mixing charcoal and introducing it during the paper production. A method to produce paper without charcoal, aiming at being used for a filter of an aerosol generating article is already known in the art such as for example in WO2019149742 or US2021195939. Impregnated charcoal paper is for example obtained by mixing very fine particles of charcoal with cellulose pulp in the production of paper. In the manufacturing of impregnated charcoal paper, paper sheets of impregnated charcoal may be crimped. A crimped paper sheet enables to increase the fluffiness of the paper and so occupying more volume. With this method, the charcoal in the impregnated charcoal paper may be high activated carbon or normal activated carbon.

Alternatively, the manufacturing of the impregnated charcoal paper comprises producing a filter paper according to a known method. Then, charcoal is sprayed on the filter paper with binder to make it impregnate the filter paper. The paper obtained after spraying the filter paper is an impregnated charcoal paper. With this method, the charcoal in the impregnated charcoal paper may be normal activated carbon. According to some embodiments, the impregnated charcoal paper is a gathered sheet of paper, preferably defining a charcoal linear density of charcoal comprised between 0,05 and 0,5 mg / 12 mm.

With a gathered sheet as such preferably with charcoal linear density in the preferred range of values, a milder or smoother tobacco taste can be conferred to the aerosol, while its added flavour is enhanced.

According to some embodiments, the upstream end filter portion has a pressure drop per unit length comprised:

- between 4 and 10 mmWG/mm, preferably between 5 to 8mmWG/mm, most preferably 5 to 7 mmWG/mm, if it contains the flavouring capsule (82; 182; 382); and

- between 0,01 to 2 mmWG/mm if the flavouring capsule is not contained in the upstream end filter portion, wherein the pressure drop is determined by the ISO 6565:2015 standard.

With said feature, the flavouring capsule has limited effect on the resistance to puff.

According to some embodiments, the mouth end filter portion comprises filter paper or nonwoven substrate.

With this feature, the biodegradability of the filter according to the invention can be improved.

According to some embodiments, the density of the filter paper in the mouth end filter portion is comprised between 0,1 mg/mm³ and 0,3 mg/mm³, and advantageously between 0,13 mg/mm³ and 0,28 mg/mm³, more preferably 0.15 mg/mm³ and 0.25 mg/mm³.

According to some embodiments, the density of the impregnated charcoal paper in the upstream end filter portion is comprised between 0,120mg/mm³ and 0,220 mg/mm³, and advantageously between 0,140 mg/mm³ and 0,200 mg/mm³.

The density of impregnated charcoal paper can be successfully lowered compared to standard charcoal filter typically consisting of mixing loose charcoal granules to paper sheet since in the latter paper must be compressed and so densified to avoid charcoal to fall off or concentrate in smaller region of the filter. The density of the filter paper in the mouth end is preferably higher than the density of the impregnated charcoal paper in the upstream end filter portion. As a result, release of solid particles off the mouth end can be prevented.

These features make it possible to provide an appropriate puff resistance and taste of the aerosol, which satisfy user.

According to some embodiments, the filter further comprises a cavity middle portion extending between the upstream end filter portion and the mouth end filter portion and wherein the flavouring capsule is located in the cavity middle portion.

The cavity middle portion makes it possible to reduce the resistance to puff by reducing the pressure drop of the filter compared to a filter with a capsule embedded in a filter portion.

According to some embodiments, the flavouring capsule is located in the mouth end filter portion.

With this feature, there is no risk that the impregnated charcoal interacts with the flavour of the flavouring capsule. The release of flavour may also be perceived more intensively due to the proximity of the mouth end.

Moreover, the resistance to draw of the filter can be maintained low as it is possible to reduce the density of the impregnated paper filter (and so reduce pressure drop of the upstream end filter portion) without prejudicing the defined position of the capsule.

In addition, with this feature, the upstream end filter portion can be manufactured by manufacturing first a first continuous rod and then, cutting this rod to form a plurality of segments.

The manufacturing of the mouth end filter portion may comprise manufacturing a second continuous rod comprising a plurality of capsules trapped in segments regularly spaced from each other. Then, the second continuous rod may be cut to obtain separately each segment which is assembled then with a segment of the first rod. Alternatively, the second continuous rod may be cut to obtain continuous pairs of segments. Then, each pair may be completed on either side by a segment of the first rod and an aerosol generating substrate. After, each pair of segments is separated to obtain two aerosol generating articles.

According to some embodiments, the flavouring capsule is located in the upstream end filter portion.

With this feature, a first continuous rod comprising charcoal paper and flavoring capsules may be manufactured and cut to form upstream end filter portions, as previously described.

A second continuous rod may then be cut to form mouth end filter portions, as previously described. Alternatively, the mouth end filter portions can be cut first to form pairs and after assembling with the other parts of the article, be cut between them.

According to some embodiments, the filter further comprises a second flavouring capsule located in the mouth end filter portion.

With this feature, an additional choice of flavour or a combination of two flavours is made possible on demand while the overall pressure resistance of the filter is significantly lower compared to conventional double-capsule filters. Overall, four possible different combinations of taste can be selected by the user.

According to some embodiments, the upstream end filter portion comprises an upstream end filter wrapper having a basis weight above 25 gsm, preferably between 45 gsm and 100 gsm, more preferably between 50 gsm and 80 gsm.

With the flavouring capsule contained in the upstream end filter portion comprising charcoal, the basis weight of the filter wrapper can be relatively low due to the firmness of the charcoal paper necessary to keep the capsule stable in the portion.

According to some embodiments, the upstream end filter portion comprises an upstream end filter wrapper having a basis weight above 45 gsm, preferably between 45 gsm and 120 gsm, more preferably between 80 gsm and 100 gsm In absence of the flavouring capsule contained in the upper end filter portion, the basis weight of the filter wrapper can be higher to provide enough firmness to the charcoal filter portion.

The flavoring capsule of the invention has a diameter preferably comprised between 2,5 and 4,5 mm. The flavoring capsule may comprise a shell containing a flavoring agent releasable while vaping. When the flavouring capsule is located in the mouth end filter portion or in the upstream end filter portion, the diameter of the flavouring capsule is preferably at least 0.4 time, more preferably at least 0.5 to 0.8 time the diameter of the filter portion (without considering the thickness of the wrapper). When the flavouring capsule is located in the cavity middle portion, the diameter of the flavouring capsule is preferably at least 0.4 time, more preferably at least 0.5 to 0.8 time the diameter of the cavity.

According to some embodiments, the upstream end filter portion and the mouth end filter portion are wrapped by a common filter wrapper.

Thanks to this feature, the upstream end filter portion and the mouth end filter portion can be easily assembled together.

The present invention also concerns an aerosol generating article comprising:

- an aerosol generating substrate delimiting a downstream end; and

- a filter as previously defined.

According to some embodiments, the aerosol generating article further comprises a cooling or distancing element interposed between the aerosol generating substrate and the filter.

With the cooling or distancing element, the user experience can be further improved since the aerosol can be cooled before achieving the user’s mouth and/or lips. The cooling or distancing element can be formed by a tube extending between the filter and the aerosol generating substrate. The tube can be hollow or contain additional flow guides mixing for the example the flow issued from the aerosol generating substrate and/or increasing the cooling of the aerosol.

The tube is preferably made of paper or cellulose acetate. It may comprise a ventilation region, such as circumferentially arranged perforations, to dilute aerosol with fresh air at a certain ventilation ratio (e.g., 60-80%) and help cooling the aerosol. The cooling or distancing element can be assembled with the filter by a wrapper, such as a tipping paper which may further extend in upstream direction to also connect the aerosol generating substrate to the cooling or distancing element. The wrapper may also be provided with perforations to allow air to enter in the cooling or distancing element. In an alternative, the ventilation region is provided in the location of the upstream filter segment, e.g., by holes provided through the wrapper circumventing the upstream filter segment.

The aerosol generating substrate preferably comprise an aerosol forming agent and tobacco material. The content of the aerosol forming agent in the aerosol generating substrate is preferably of at least 10 wt.% in dry basis, more preferably comprised between 11 and 30 wt.% of the aerosol generating substrate. The aerosol forming agent may be polyol, such as glycerol, propylene glycol, or 1 ,3-butanediol or a combination thereof.

According to some embodiments, the aerosol generating article may be further configured for use with a Heat not Burn generating device. The invention also concerns a system comprising an article as aforementioned and a Heat not Burn generating device comprising a socket configured to receive the article.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and its advantages will be better understood upon reading the following description, which is given solely by way of none-limiting examples and which is made with reference to the appended drawings, in which.

Figure 1 is a schematic diagram of an aerosol generating assembly comprising an aerosol generating article according to the invention;

Figure 2 is a perspective view of the aerosol generating article of Figure 1 , the aerosol generating article comprising a filter according to the invention;

Figure 3 is a schematic exploded view of the filter of Figure 2, the filter being according to a first embodiment of the invention;

Figure 4 is a schematic exploded view of the filter of Figure 2, the filter being according to a second embodiment of the invention; Figure 5 is a schematic exploded view of the filter of Figure 2, the filter being according to a third embodiment of the invention; and

Figure 6 is a schematic exploded view of the filter of Figure 2, the filter being according to a fourth embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Before describing the invention, it is to be understood that it is not limited to the details of construction set forth in the following description. It will be apparent to those skilled in the art having the benefit of the present disclosure that the invention is capable of other embodiments and of being practiced or being carried out in various ways.

The expression “substantially equal to” is understood hereinafter as an equality at plus or minus 10% and preferably at plus or minus 5%.

As used herein, the term “aerosol generating device” or “device” may include a vaping device to deliver aerosol from an aerosol generating article received in the device, for example comprising tobacco. The device may be portable. “Portable” may refer to the device being for use when held by a user. The device may be adapted to generate a variable amount of aerosol, e.g. by activating a heating system for a variable amount of time (as opposed to a metered dose of aerosol) using a trigger. The trigger may be user activated, such as a vaping button and/or inhalation sensor. The inhalation sensor may be sensitive to the strength of inhalation as well as the duration of inhalation to enable a variable amount of vapor to be provided (so as to mimic the effect of smoking a conventional combustible smoking article such as a cigarette, cigar or pipe, etc.).

As used herein, the term “control unit” refers to a component of the aerosol generating device and may control the operation of the heating system. The control unit may include a temperature regulation control to drive the temperature of the heating system thereafter to maintain the temperature.

As used herein, the term “aerosol generating substrate” is used to designate any material that is able to form aerosol. The aerosol is generally obtained by a temperature increase of the aerosol generating substrate, such as at a temperature less than 400°C, preferably up to 350°C. The aerosol generating substrate may, for example, comprise or consist in an aerosol-generating solid that may be in the form of a rod, which contains processed tobacco material, a crimped sheet or oriented strips of reconstituted tobacco (RTB), or any combination of these. The aerosol generating substrate may comprise one or more of: nicotine, caffeine or other active components.

As used herein, the term “aerosol” may include a suspension of precursor as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. Aerosol may be formed by the aerosol generating substrate and may comprise one or several components of it.

As used herein, the term “vaping session” may refer to a using period of the aerosol generated device starting from the activation of the trigger defined above to the moment in which the aerosol generation device is disabled.

As used herein, the term “pressure drop” refers to the static pressure difference between two ends of the component considered (e.g., filter portion, filter or aerosol generating article) when it is traversed by an air flow under steady conditions in which the volumetric flow is 17,5 ml s-1 . The standard conditions for the determination of the pressure drop are described in ISO6565:2015.

As represented in Figure 1 , an aerosol generating assembly 10 comprises an aerosol generating device 15 and an aerosol generating article 20.

The aerosol generating device 15 extends along an axis X called hereinafter “device axis X”. The aerosol generating device 15 comprises an outside casing 22 and internal components arranged in the outside casing 22. The outside casing 22 delimits an article socket 26 and at least one flow inlet 28 for air to enter in the socket 26. The internal components comprise for example a heating system 30 to heat at least a part of the aerosol generating article 20, a battery 24 for powering the heating system 30 and a control unit 32 to control powering of the heating system 30 by the battery 24.

The battery 24 is for example a known battery designed to be charged using a power supply furnished by an external charger, and designed to provide direct current of a predetermined voltage to the heating system 30. The article socket 26 is configured to receive at least a part of the aerosol generating article 20. For this purpose, the article socket 26 may delimit a hole 36 opening at the exterior of the aerosol generating device 15 and is adapted to receive at least a part of the aerosol generating article 20 in said hole 36. In Figure 1 , the aerosol generating article 20 is inserted into the hole 36.

The flow inlet 28 allows air entering from the exterior of the outside casing 22. An internal airflow channel may extend from the flow inlet 28 to conduct the air until the article socket 26. The flow inlet 28 may be formed as a part of the hole 36. In particular, the flow inlet may be a part of the hole 36 which is not occupied by the article when inserted in the socket 26 and the air flow may be channeled from the flow inlet to the article through a gap arranged between the cavity of the socket and the article such as described in W02020074602.

The heating system 30 comprises for example a heating element, e.g. a thin resistive film, which may be arranged adjacent to at least a wall of the article socket 26. The heating system is for example, connected to the battery 24, and configured to produce heat when powered by the battery 24. When the aerosol generating article 20 is inserted in the hole 36, and when the heating system 30 is powered by the battery 24, the temperature of said heating system 30 is for example comprised between 200 degrees and 350 degrees.

In a non-represented variant, the heating system 30 comprises a device part of the heating system and an article part of the heating system. The device part of the heating system may comprise electromagnetic emitter(s) configured to produce electromagnetic field when powered by the battery 24. The emitter(s) can comprise for example a magnetic coil arranged around the article socket 26. The article part of the heating system may thus comprise susceptors configured to produce heat when being traversed by an electromagnetic field. The susceptors can for example be integrated in the aerosol generating substrate of the article 20.

The control unit 32 is adapted to control the operation of the heating system 30. More specifically, the control unit 32 is configured to control powering of the heating system 30 by the battery 24.

As shown in Figure 2, the aerosol generating article 20 comprises an aerosol generating substrate 40, a filter 45, an article wrapper 47 and in some embodiments, a cooling or distancing element 42 arranged between the aerosol generating substrate 40 and the filter 45.

In a preferred example, the length of the aerosol generating substrate 40 is comprised between 10 and 30 mm, preferably between 15 and 25 mm, more preferably substantially equal to 20 mm (+/- 2 mm). In said example, the length of the filter 45 is comprised between 10 and 30 mm, preferably between 15 and 25 mm, more preferably substantially equal to 20 mm (+/- 2 mm). In said example, the length of the cooling or distancing element 42 is comprised between 10 and 30 mm, preferably between 15 and 25 mm, more preferably substantially equal to 20 mm (+/- 2 mm).

Preferably, the length of the aerosol generating article 20 is comprised between 40 and 90 mm, more preferably 50 and 70 mm, most preferably 55 and 65 mm, such as substantially equals to 60 mm (+/- 2 mm).

The aerosol generating substrate 40 comprises a downstream end 50 adjacent to the cooling or distancing element 42 in the example of Figure 2 or to the filter 45 when no cooling or distancing element 42 is provided. The aerosol generating substrate 40 is designed to be heated by the heating system 30 of the aerosol generating device 15 to form aerosol, as previously explained.

The cooling or distancing element 42 provides a sufficient distance between the aerosol generating substrate 40 and the mouth end with negligible impact on the pressure resistance of the article 20. The cooling or distancing element 42 may be configured to cool the aerosol before reaching the filter 45. The cooling or distancing element 42 is for example a hollow tube and is preferably made of paper. During a vaping session, the aerosol generated by the aerosol generating substrate 40 flows through the cooling or distancing element 42 before reaching the filter 45. For example, the cooling or distancing element 42 is hollow or contains additional flow guides mixing the flow issued from the aerosol generating substrate 40 and/or increasing the cooling effect. The hollow tube preferably abuts against the aerosol generating substrate 40 and connected by a wrapper 47 (also referred as “tipping paper”). The cooling or distancing element 42 can further comprise a ventilation area, preferably formed by ventilation holes arranged in at least one row of circumferentially arranged holes traversing the wall of the cooling or distancing element 42. The holes may be formed through the hollow tube of the element as well as through the wrapper 47 to allow air to communicate from the external side to the hollow inside of the element. The ventilation holes should preferably be positioned at a short distance from the filter 45, preferably at a distance comprised between 1 mm and 7 mm, more preferably 2,5 mm and 6 mm, most preferably 3 mm and 5,5 mm. The cooling or distancing element 42 could alternatively be simply formed by a portion of the thick wrapper 47 between the substrate 40 and the filter 45. The cooling or distancing element may be defined as described in EP4042889A1 , “(2) Cooling segment”, paragraphs 17-19, incorporated here by reference.

The aerosol generating substrate 40, the filter 45, and optionally the cooling or distancing element 42 are maintained together with the article wrapper 47. As represented in Figure 2, the article wrapper 47 may be formed by a unique wrapper extending along at least a part of the aerosol generating article 20. For example, as shown in Figure 3, the article wrapper 47 can cover entirely the filter 45, the cooling or distancing element 42 and partially the aerosol generating substrate 40. According to other embodiments, the filter 45 can be partially uncovered and/or the aerosol generating substrate 40 can be covered entirely. According to still another embodiment, the article wrapper 47 extends along the entire length of the aerosol generating article 20. In a non-represented variant, the article wrapper 47 comprises several wrappers arranged along the aerosol generating article 20. The wrappers can overlap each other and are maintained together for example using glue at the overlapping location.

The filter 45 extends along a filter axis F, between an upstream end 55 and a mouth end 60. In the example of Figure 2, the upstream end 55 is in contact with the cooling or distancing element 42 or when no cooling or distancing element 42 is provided, the upstream end 55 can be in contact with the downstream end 50 of the aerosol generating substrate 40. In any case, the upstream end 55 and the downstream end 50 are in fluid communication. In other words, during a vaping session, when the user inhales, aerosol produced by the aerosol generating substrate 40 passes through the downstream end 50 and through the cooling or distancing element 42 before reaching the upstream end 55. The mouth end 60 of the filter 45 is intended to be received in the mouth of the user.

The filter 45 can be carried out according to one of the embodiments explained below.

FIRST EMBODIMENT OF THE INVENTION According to a first embodiment shown in Figure 3, the filter 45 comprises a mouth end filter portion 65 adjacent to the mouth end 60 and an upstream end filter portion 70 adjacent to the upstream end 55. The mouth end filter portion 65 and the upstream end filter portion 70 form separate filter segments that are maintained contiguous, as it will be detailed below.

The length of the mouth end filter portion 65 may be comprised between 5 mm and 12 mm, preferably between 6 mm and 10 mm and more preferably substantially equal to 8 mm.

The length of the upstream end filter portion 70 may be comprised between 8 mm and 16 mm, preferably between 10 mm and 14 mm, and more preferably substantially equal to 12 mm.

The mouth end filter portion 65 comprises filter paper 77. The filter paper material 77 is formed from a gathered sheet of paper. The sheet may further be crimped. A crimped paper sheet enables to increase the fluffiness of the paper and so occupying more volume it enables.

Alternatively, the filter paper 77 comprises paper and is preferably made of paper. The filter paper is preferably a gathered sheet of paper. The basis weight of the filter paper sheet 77 is for example comprised between 20 and 120 gsm, preferably substantially equal to 35 gsm. The thickness of the filter paper 77 is for example comprised between 30 rm and 100 rm. The porosity of the filter paper 77 is preferably comprised between 0 and 3 000 CU. The contact angle of the filter paper 77 is lower than 90°. The tensile strength of the filter paper 77 is higher than 18 N per 15 mm. Advantageously, the filter paper 77 is made of one single sheet, like a paper tape for example, by folding this sheet to form several layers extending along the filter axis F.

In some embodiments, the mouth end filter portion 65 may also comprise a mouth end filter wrapper 80 wrapping the filter paper 77 of the mouth end filter portion 65. The wrapper 80 can be made of a paper which is preferably coated with a material resisting staining by the flavor substance. This material can be oleophobic and/or hydrophobic.

In the first embodiment, the mouth end filter portion 65 comprises a flavoring capsule 82 trapped in the filter paper 77. During a vaping session, the aerosol passes through the upstream end filter portion 270, through the mouth end filter portion 65, get in contact with the flavoring capsule 82 to be loaded with the flavor of the flavoring capsule 82, and then reaches the user’s mouth.

The flavoring capsule’s diameter can be comprised between 2,5 and 4,5 mm. The flavoring capsule 82 can comprise a shell containing a flavoring agent releasable while vaping. The flavoring agent may for example be liquid or powder. The flavouring agent may be, for example menthol, peppermint, berry, lemon, peach, apple, cardamon, cherry, celery, fenugreek, bergamot, jasmine, ginger, orange oil, lemon oil, cassia, etc.

The shell of the flavoring capsule 82 is preferably breakable by a pinch of the user on the mouth end filter portion 65. After such pinch, the flavoring agent spreads in the mouth end filter portion 65 and is absorbed by the filter paper 77. The capsule 82 may be one as described in EP 1906775 B1. For example, the shell of the capsule may comprise at least one hydrocolloid selected from gellan gum, agar, alginates, carrageenan, pectin, Arabic gum, ghatti gum, pullulan gum, mannan gum or modified starch, alone or as a mixture thereof or combination thereof. In such case, during a vaping session, the aerosol passing through the mouth end filter portion 65 is loaded with the flavor of the liquid initially contained in the flavoring capsule 82.

To manufacture the mouth end filter portion 65, after the filter paper 77 has been crimped (optional) and then gathered, multiple portions are formed as a rod with flavoring capsules 82 inserted in the filter paper 77 at regular intervals and the mouth end filter wrapper 80 is wrapped around the rod. The rod is then cut to individual mouth end filter portions 65 or dual length for assembling with the upstream end filter portion 70.

The upstream end filter portion 70 forms a low pressure drop filter segment. For example, the pressure drop per unit length of the upstream end filter portion 70 is preferably between 0,01 to 2 mmWG per mm. The upstream end filter portion 70 for example comprises impregnated charcoal paper 83 as the mouth end filter portion 65. Preferably, the upstream end filter portion 70 is only made of impregnated charcoal paper 83. The impregnated charcoal paper 83 may be the same paper as the filter paper 77, which has been impregnated with charcoal. As an alternative the upstream end filter portion 70 and the mouth end filter portion 65 are made of impregnated charcoal nonwoven. With the impregnated charcoal paper, when the user inhales, aerosol generated by the aerosol generating substrate passes through the filter wherein it is in contact with charcoal before reaching the user’s mouth. During such contact, the charcoal absorbs undesired compounds in gas or aerosol phase.

The charcoal in the impregnated charcoal paper 83 may be activated carbon paper having a basis weight comprised between 40 and 60 gsm, most preferably of about 43 gsm.

The charcoal linear density of the impregnated charcoal paper 83 is comprised between 0,05 mg per 12 mm (also denoted mg/12mm) and 0,5 mg per 12 mm, and more preferably comprised between 0,1 mg/12 mm and 0,3 mg/12 mm.

The charcoal linear density is defined as the quantity of charcoal present in a sample of paper cut as a rectangle of 1 mm of width per 12 mm of length.

The manufacturing of the impregnated charcoal paper 83 may comprise mixing charcoal and introducing it during the paper production. A method to produce paper without charcoal, aiming at being used for a filter of an aerosol generating article is already known in the art. This method produces sheets of impregnated charcoal paper that may be crimped. A crimped paper sheet enables to increase the fluffiness of the paper and so occupying more volume. With this method, the charcoal in the impregnated charcoal paper 83 may be high activated carbon or normal activated carbon.

Alternatively, the manufacturing of the impregnated charcoal paper 83 comprises producing a filter paper 77. Then, when producing the upstream end filter portion 70, charcoal is sprayed on the filter paper 77 with binder to make it impregnate the filter paper 77. The paper obtained after spraying the filter paper 77 is an impregnated charcoal paper 83. With this method, the charcoal in the impregnated charcoal paper 83 may be preferably normal activated carbon.

The advantage of the impregnated charcoal compared to other kind of normal activated carbon is to enable to decrease the pressure drop of the aerosol.

Similarly to the filter paper 77, the impregnated charcoal paper 83 may be made of one single sheet, like a paper tape for example, by folding this sheet to form several layers extending along the filter axis F. The cross-sectional densities of the filter paper 77 of the mouth end filter portion 65, and of the impregnated charcoal paper 83 of the upstream end filter portion 70 can be substantially identical or different.

For example, according to one embodiment, the cross-sectional density of the filter paper 77 of the mouth end filter portion 65 may be greater than the corresponding density of the impregnated charcoal paper 83 of the upstream end filter portion 70. In this case and in the first embodiment, for example the same quantity of paper 77, 83 can be used to form both filter portions 65, 70. However, since the flavoring capsule 82 is inserted in the mouth end filter portion 65, the filter paper 77 of the mouth end filter portion 65 can present a greater cross-sectional density.

Preferably, the density of the filter paper 77 in the mouth end filter portion 65 is comprised between 0,1 mg/mm³ and 0,3 mg/mm³, and advantageously between 0,15 mg/mm³ and 0,25 mg/mm³.

Similarly, the density of the impregnated charcoal paper 83 in the upstream end filter portion 70 without capsule is comprised between 0,120 mg/mm³ and 0,220 mg/mm³, and advantageously between 0,140 mg/mm³ and 0,200 mg/mm³.

According to some embodiments, the upstream end filter portion 70 also comprises an upstream end filter wrapper 85 wrapping the impregnated charcoal paper 83 of the upstream end filter portion 70. As the mouth end filter wrapper 80, the upstream end filter wrapper 85 can for example be made of paper. Preferably, this wrapper 85 is of paper material preferably coated with a substrate preventing staining from oily or aqueous substances.

In some embodiments, at least one among the mouth end filter wrapper 80 and the upstream end filter wrapper 85 is made in one piece with the corresponding paper 77, 83. Thus, in this case, a first portion of the paper 77, 83 can be folded to form several layers and a second portion can then wrap the folded layers to form the corresponding wrapper 80, 85.

Preferably, the basis weight of the filter wrapper 80 of the mouth end filter portion 65 is 20-70 gsm and the thickness can be substantially between 30 and 80 rm. The basis weight of the filter wrapper 85 of the upstream end filter portion 70 is preferably above 45 gsm, preferably between 45 gsm and 120 gms, and more preferably between 80 gsm and 100 gsm and the thickness can be substantially between 80 and 125 rm.

In this first embodiment, to manufacture the upstream end filter portion 70, impregnated charcoal paper 83 may be folded to form a continuous tube. The upstream end filter wrapper 85 then surrounds the continuous tube. The tube can be cut at a predetermined distance to form the upstream end filter portion 70.

The upstream end filter wrapper 85 has a basis weight above 45 gsm, preferably between 45 gsm and 120 gsm, more preferably between 80 gsm and 100 gsm.

The mouth end filter portion 65 and the upstream end filter portion 70 are maintained together with a common outer wrapper 87, which has for example a length equal to the sum of the lengths of the mouth end filter portion 65 and of the upstream end filter portion 70. The common outer wrapper 87 is for example a plug wrap. Preferably, the basis weight of the plug wrap is substantially equal to 20-70 gsm and the thickness of the plug wrap is substantially equal to 30-80 rm. For example, the plug wrap has a basis weight of 50 gsm and a thickness of 76 /rm.

Optionally, at least one of the upstream end filter portion 70 and the mouth end filter portion 65 comprises a taste improving or performance enhancing additive. Such taste improving additive is for example flavourants such as menthol, peppermint, berry, lemon, peach, apple, cardamon, cherry, celery, fenugreek, bergamot, jasmine, ginger, orange oil, lemon oil, cassia, coffee, tobacco powder, herbs, spices, flavour enhancers, sugars, sugar substitutes and combinations thereof which, when being in contact with aerosol, enhances and/or modify the taste of the aerosol. A performance additive may be glycerin, PG, PPG, or lactic acid or combinations thereof.

To manufacture an aerosol generating article 20 having a filter 45 according to the first embodiment of the invention, it is possible to manufacture a first continuous rod of impregnated charcoal paper and then, cut this rod to form a plurality of upstream end filter portions 70. Then, it is possible to manufacture a second continuous rod of paper comprising a plurality of capsules trapped in segments regularly spaced from each other. Each segment of the second rod is designed to form a mouth end filter portion 65. After, the second continuous rod may be cut to obtain continuous pairs of segments. Then, each pair may be completed on either side by a segment of the first rod, i.e. an upstream end filter portion 70, and an aerosol generating substrate. After, each pair of segments is separated to obtain two aerosol generating articles 20.

The same manufacturing process can also be applied to form aerosol generating articles comprising filters according to other embodiments described below.

SECOND EMBODIMENT OF THE INVENTION

A filter 145 according to a second embodiment will now be described with reference to Figure 4 and only by its differences with the filter 45 according to the first embodiment. It has to be considered that each element which is not described in this second embodiment is similar to the corresponding element of the first embodiment.

According to the second embodiment, the filter 145 comprises the mouth end filter portion 165 and an upstream end filter portion 170.

The mouth end filter portion 165 according to the second embodiment is similar to the mouth end filter portion 65 according to the first embodiment, except the fact that it does not comprise the flavoring capsule 82.

The upstream end filter portion 170 according to the second embodiment is similar to the upstream end filter portion 70 according to the first embodiment, except the fact that it comprises a flavoring capsule 182. The flavoring capsule 182 according to the second embodiment is similar to the flavoring capsule 82 according to the first embodiment.

In order to keep stability of the capsule 182 in the upstream end filter portion 170, the cross-sectional density of the upstream end filter portion 170 is preferably greater than the cross-sectional density of the mouth end filter portion 165. As a result, the upstream end filter portion 170 is higher than the pressure drop of the mouth end filter portion 165. For example, the pressure drop of the upstream portion 170 is about 137 mmWG per 24 mm and the pressure drop of the mouth end filter portion 165 is about 40 to 60 mmWG per 24 mm.

In other words, the pressure drop per unit length of the upstream end filter portion 170 is comprised between 4 and 8 mmWG/mm, most preferably between 5 and 7 mmWG/mm. To manufacture an aerosol generating article comprising a filter 145 according to the second embodiment, a process similar to one explained above can be used. According to this embodiment, instead of placing a plurality of capsules in the second continuous rod, the capsules may be placed in the first continuous rod.

According to the second embodiment, the upstream end filter wrapper 85 has a basis weight above 25 gsm, preferably between 45 gsm and 100 gsm, more preferably between 50 gsm and 80 gsm.

The density of the impregnated charcoal paper 83 in the upstream end filter portion 170, which does not comprise a flavoring capsule, is comprised between 0,130 mg/mm³ and 0,220 mg/mm³, and advantageously between 0,140 mg/mm³ and 0,200 mg/mm³.

THIRD EMBODIMENT OF THE INVENTION

A filter 245 according to a third embodiment will now be described with reference to Figure 5 and only by its differences with the filter 45 according to the first embodiment. It has to be considered that each element which is not described in this third embodiment is similar to the corresponding element of the first embodiment.

According to the third embodiment, the filter 245 comprises a mouth end filter portion 65 according to the first embodiment and the upstream end filter portion 170 according to the second embodiment.

Thus, the mouth end filter portion 65 comprises a first flavoring capsule 82 and the upstream end filter portion 70 comprises a second flavoring capsule 182.

The first 82 and the second 182 flavoring capsules are for example similar, with the same flavoring agent.

Alternatively, the first 82 and the second 182 flavoring capsules are different. In other words, the first 82 and the second 182 flavoring capsules may have different types of shell, and/or different flavoring agents with different tastes. Preferably, in order to keep pressure of the filter as low as possible, the cross- sectional density of the mouth end filter position 65 is preferably equal to the cross-sectional density of the upstream end filter portion 170.

To manufacturer an aerosol generating article comprising a filter 245 according to the third embodiment, the same process as the ones explained above can be used. According to this embodiment, a plurality of capsules can be trapped in each rod.

FOURTH EMBODIMENT OF THE INVENTION

A filter 345 according to a fourth embodiment will now be described with reference to Figure 6 and only by its differences with the filter 45 according to the first embodiment. It has to be considered that each element which is not described in this fourth embodiment is similar to the corresponding element of the first embodiment.

According to the fourth embodiment, the filter 345 comprises a mouth end filter portion 365 adjacent to the mouth end 60, an upstream end filter portion 70 adjacent to the upstream end 55 and a cavity middle portion 375, also called cavity portion 375.

The mouth end filter portion 365 according to the fourth embodiment is similar to the mouth end filter portion 65 according to the first embodiment except that it does not comprise the flavoring capsule 82. The length of the mouth end filter portion 365 is preferably between 5 to 9 mm, more preferably about 7 mm.

The upstream end filter portion 370 according to the fourth embodiment is similar to the upstream end filter portion 70 according to the first embodiment except that it is substantially shorter.

Actually, the length of the upstream end filter portion 370 may be comprised between 5 mm and 9 mm, preferably about 8 mm

The middle cavity portion 375 extends between the mouth end filter portion 365 and the upstream end filter portion 370.

The middle cavity portion 375 is formed by the common outer wrapper 87 extending between the filter portions 365, 370. The upstream end filter portion 370 and the mouth end filter portion 365 are spaced apart a certain length to provide the cavity portion 375. The length of the cavity portion may vary from 4 to 7 mm, preferably is about 5 mm.

The common outer wrapper 87 is for example a plug wrap. Preferably, the basis weight of the outer wrapper is substantially comprised between 20 and 70 gsm and the thickness of the plug wrap is substantially comprised between 30 and 80 rm. For example, the plug wrap has a basis weight of 50 gsm and a thickness of 76 rm.

An example for the filter dimensions are equal to 7 mm for the upstream end filter portion 370, 5 mm for the cavity middle portion 375, 8 mm for the mouth end filter portion 365, and 3,5 mm for the capsule diameter.

In the fourth embodiment, the cavity portion 375 comprises a flavoring capsule 382.

The flavoring capsule 382 of the fourth embodiment is similar to the flavoring capsule 82 of the first embodiment.

Optionally, the cavity portion 375 comprises a taste improving or performance enhancing additive. Such taste improving additive is for example a flavourant such as menthol, peppermint, berry, lemon, peach, apple, cardamon, cherry, celery, fenugreek, bergamot, jasmine, ginger, orange oil, lemon oil, cassia, coffee, tobacco powder, herbs, spices, flavour enhancers, sugars, sugar substitutes and combinations thereof which, when being in contact with aerosol, enhances and/or modify the taste of the aerosol. A performance additive may be glycerin, PG, PPG, or lactic acid.

To manufacturer an aerosol generating article comprising a filter 345 according to the fourth embodiment, the same process as the ones explained above can be used. According to this embodiment, a capsule can be trapped between the mouth end filter portion and the upstream end filter portion while assembling these portions together.

OPERATION OF THE INVENTION

It will now be described the operation of the aerosol generating article 20 and more specifically of the filter 45, 145, 245, 345 according to the invention Initially, the aerosol generating article 20 is inserted in the article socket 26 of the aerosol generating assembly 10.

Preferably, the user pinches the filter 45, 145, 245, 345 to crush the capsule(s) 82, 182, 382.

During a vaping session, the aerosol generating substrate 40 is heated and release aerosol. When the user inhales, the aerosol is vacuumed through the aerosol generating article 20. Particularly, the aerosol passes through the aerosol generating substrate 40 until the downstream end 50. If applicable, the aerosol then passes through the cooling or distancing element 42 wherein it is cooled. Then, the aerosol reaches the upstream end 55 of the filter 45.

The aerosol then passes through the upstream end filter portion 70, 170, 370 wherein its pressure slightly drops. The aerosol gets in contact with the impregnated charcoal paper 83. The charcoal in the impregnated charcoal paper 83 absorbs gas phase toxins in the aerosol including hydrogen cyanide, formaldehyde, ammonia and crotonaldehyde.

If the filter 145, 245 is according to the second, respectively to the third embodiment, the aerosol reaches the flavoring capsule 182, respectively the second flavoring capsule 182. Preferably, the aerosol reaches the flavoring agent of the crunched flavoring capsule 182. The aerosol thus gets loaded with the flavor of the flavoring agent.

Alternatively, if the filter 345 is according to the fourth embodiment, the aerosol flows through the upstream end filter portion 370 and reaches the cavity portion 375. The aerosol reaches the flavoring capsule 382. Preferably, the aerosol reaches the flavoring agent of the crunched flavoring capsule 382. The aerosol thus gets loaded with the flavor of the flavoring agent.

Then, the aerosol reaches the mouth end filter portion 65, 165, 365. The aerosol passes through the filter paper 77 wherein its pressure only slightly drops again.

If the mouth end filter portion 65 is according to the first or the third embodiment, the aerosol then reaches the flavoring capsule 82. Preferably, the aerosol reaches the flavoring agent of the crunched flavoring capsule 82. The aerosol thus gets loaded with the flavor of the flavoring agent.

Eventually, the aerosol reaches the mouth end 60. The aerosol then enters the user’s mouth.

The overall pressure drop per unit length (PD/mm) of the filter 45, 145, 245, 345 according to the invention is preferably: below 6,1 mmWG per mm. More precisely, PD/mm is 4,0 mmWG/mm for filter 45; 5,0 mmWG/mm for filter 145; 6,0 mmWG per mm for filter 245 and 1 ,0 mmWG/mm for filter 345. The target pressure drop of the aerosol generating article 20 as a whole, can be comprised between 1 and 7 mmWG/mm. The pressure drop is determined under standard conditions according to ISO 6565:2015. The pressure drop is the static pressure, expressed in mmWG or Pascal (1 mmWG=9.8067 Pa), determined by a calibrated/adjusted pressure-drop instrument, between the two ends of the tested filter segment when it is traversed by an air flow under steady conditions in which the measured volumetric flow, under standard conditions, at the output end is 17.5 ml/s. The filter samples are completely encapsulated in an impermeable sleeve to prevent air ‘short-circuiting’ down the outside of the sample. The pressure drop per unit length (PD/mm) is obtained by measuring a filter sample between 96 to 120 mm and by dividing the pressure drop value by the length in millimeter of the filter.

Claims

1 A filter (45; 145; 245; 345) for an aerosol generating article (20), the filter (45; 145; 245; 345) extending along a filter axis (F) between an upstream end (55) and a mouth end (60), the upstream end (55) being configured to be in fluid communication with a downstream end (50) of an aerosol generating substrate (40); the filter (45; 145; 245; 345) comprising:

- an upstream end filter portion (70; 170; 370) delimiting the upstream end (55) and comprising impregnated charcoal paper or nonwoven substrate (83);

- a mouth end filter portion (65; 165; 365) delimiting the mouth end (60);

- at least one flavouring capsule (82; 182; 382) and wherein the mouth end filter portion (65; 165; 365) comprises filter paper or nonwoven substrate (77).

2.- The filter (45; 145; 245; 345) according to claim 1 , wherein the impregnated charcoal paper (83) is a gathered sheet of paper, preferably defining a linear density of charcoal comprised between 0,05 and 0,5 mg / 12 mm.

3.- The filter (45; 145; 245; 345) according to claim 1 or 2, wherein the upstream end filter portion (70; 170; 370) has a pressure drop per unit length comprised:

- between 4 and 10 mmWG/mm, preferably between 5 and 8mmWG/mm, most preferably between 5 to 7 mmWG/mm, if it contains the flavouring capsule (82; 182; 382); and

- between 0,01 to 2 mmWG/mm if the flavouring capsule (82; 182; 382) is not contained in the upstream end filter portion (70; 170; 370), wherein the pressure drop is determined by the ISO 6565:2015 standard.

4.- The filter (45; 145; 245; 345) according to any one of claim 1 to 3, wherein the density of the filter paper (77) in the mouth end filter portion (65; 165; 365) is comprised between 0,1 mg/mm³ and 0,3 mg/mm³, and advantageously between 0,13 mg/mm³ and 0,28 mg/mm³, more preferably between 0.15mg/mm³ and 0.25 mg/mm³.

5. The filter (45; 145; 245; 345) according to any one of claims 1 to 4, wherein the density of the impregnated charcoal paper (83) in the upstream end filter portion (70; 170; 370) is comprised between 0,120mg/mm³ and 0,220 mg/mm³, and advantageously between 0,140 mg/mm³ and 0,200 mg/mm³.

6.- The filter (345) according to any one of claims 1 to 5, further comprising a cavity middle portion (375) extending between the upstream end filter portion (370) and the mouth end filter portion (365) and wherein the flavouring capsule (382) is located in the cavity middle portion (375).

7. The filter (145; 245) according to claim 6, wherein the diameter of the flavouring capsule is preferably at least 0.4 time, more preferably at least 0.5 to 0.8 time the diameter of the cavity.

8.- The filter (45; 245) according to any one of claims 1 to 5, wherein the flavouring capsule (82) is located in the mouth end filter portion (65).

9.- The filter (145; 245) according to any claims 1 to 5, wherein the flavouring capsule (182) is located in the upstream end filter portion (170).

10. The filter (145; 245) according to claim 8 or 9, wherein the diameter of the flavouring capsule is preferably at least 0.4 time, more preferably at least 0.5 to 0.8 time the diameter of the filter portion.

1 1 .- The filter (245) according to claim 9 or 10, further comprising a second flavouring capsule (182) located in the mouth end filter portion (65).

12.- The filter (145; 245) according to any one of claims 9 to 11 , wherein the upstream end filter portion (170) comprises an upstream end filter wrapper (85) having a basis weight above 25 gsm, preferably between 45 gsm and 100 gsm, more preferably between 50 gsm and 80 gsm.

13. The filter (45; 345) according to any one of claims 1 to 8, wherein the upstream end filter portion comprises (70; 370) an upstream end filter wrapper (85) having a basis weight above 45 gsm, preferably between 45 gsm and 120 gsm, more preferably between 80 gsm and 100 gsm.

14.- The filter (45; 145; 245; 345) according to any one of the preceding claims, wherein the upstream end filter portion (70; 170; 370) and the mouth end filter portion (65; 165; 365) are wrapped by a common filter wrapper (87).

15. The filter (45; 145; 245; 345) according to any one of the preceding claims, wherein the flavoring capsule of the invention has a diameter preferably comprised between 2,5 and 4,5 mm and comprises a shell containing a flavoring agent releasable while vaping.

16.- An aerosol generating article (20) comprising:

- an aerosol generating substrate (40) delimiting a downstream end (50); and

- a filter (45; 145; 245; 345) according to any of the preceding claims.

17.- The aerosol generating article (20) according to claim 16, further comprising a cooling or distancing element (42) interposed between the aerosol generating substrate (40) and the filter (45; 145; 245; 345).