WO2024223880A1

WO2024223880A1 - Tobacco article for a heat-not-burn aerosol generating device and associated manufacturing method

Info

Publication number: WO2024223880A1
Application number: PCT/EP2024/061639
Authority: WO
Inventors: Herman HIJMA
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2023-04-28
Filing date: 2024-04-26
Publication date: 2024-10-31
Anticipated expiration: 2025-10-28

Abstract

The present invention concerns a tobacco article (12) for a heat-not-burn aerosol generating device, the tobacco article extending along an article axis between a proximal end and a distal end, and comprising a tobacco part (15) and a non-tobacco part (16) extending along the article axis; the tobacco part (15) comprising a first end (18) and the non-tobacco part (16) comprising a second end; the tobacco article (12) further comprising a plurality of layers, the tobacco part (15) being arranged between a pair of layers; wherein the plurality of layers comprises a guiding layer (820) defining a cutout forming at least partially an airflow channel (832) fluidically separated from the tobacco part (15).

Description

Tobacco article for a heat-not-burn aerosol generating device and associated manufacturing method

FIELD OF THE INVENTION

The present invention concerns a tobacco article for a heat-not-burn aerosol generating device. The present invention also concerns a manufacturing method of such a tobacco article.

Particularly, the tobacco article according to the invention comprises for example a solid substrate able to form aerosol when being heated. Thus, the aerosol generating devices operating with such type of tobacco articles, also known as heat-not-burn devices, are adapted to heat, rather than burn, the substrate by conduction, convection and/or radiation, to generate aerosol for inhalation.

BACKGROUND OF THE INVENTION

The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers) 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 the heated substrate aerosol generation device or heat-not-burn device. Devices of this type generate aerosol or vapour by heating an aerosol substrate that typically comprises moist leaf tobacco or other suitable vaporizable material to a temperature typically in the range 150°C to 350°C. Heating an aerosol 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. Tobacco articles, usable with such type of aerosol generating devices can take various forms. Some of them can present an elongated stick or any other suitable shape, like for example a flat shape. Generally, such a tobacco article is received at least partially in a heating chamber of the device which comprises one or several heaters to heat the tobacco article.

When received at least partially in the heating chamber, the tobacco article is configured to generate aerosol which is delivered to the user via the mouthpiece. In some devices, when received in the heating chamber, a tobacco article generates pollution and condensation inside the device during its operation. Thus, the device should be regularly cleaned by the user. Additionally, air flow distribution and pressure drop of some tobacco articles are not satisfying and should be improved. These issues of some conventional tobacco articles and aerosol generating devices conduct to a poor user experience.

SUMMARY OF THE INVENTION

One of the aims of the invention is to propose a tobacco article making it possible to avoid pollution and condensation generated by aerosol in the heating chamber of an aerosol generating device. This provides a more reliable and cleaner aerosol generating system. Additionally, airflow distribution and pressure drop are improved inside the tobacco article. The user experience can thus be considerably improved.

For this purpose, the invention relates to a tobacco article for a heat-not-burn aerosol generating device, the tobacco article extending along an article axis between a proximal end and a distal end, and comprising a tobacco part and a non-tobacco part extending along the article axis. The tobacco part comprises a first end and the non-tobacco part comprising a second end, the first end being adjacent to the distal end or closer to the distal end than the second end, the second end being adjacent to the proximal end or closer to the proximal end than the first end.

The tobacco article further comprises a plurality of layers, the tobacco part being arranged between a pair of layers. The plurality of layers comprises a guiding layer defining a cutout forming at least partially an airflow channel fluidically separated from the tobacco part. Provided with these features, airflow used to generate aerosol can be guided mainly through the tobacco article. Thus, any contact of the airflow with the heating chamber can be avoided or at least minimized. Thanks to these features, pollution and condensation which can be generated while operating the tobacco article, remain inside the article and can be easily evacuated from the device when the tobacco article is extracted. Additionally, the airflow used to generate aerosol can be entirely controlled inside the tobacco article by respective arrangements of the downstream and upstream airflow paths inside the article. Thus, airflow distribution inside the tobacco article can be optimized and an optimal pressure drop can be achieved.

Additionally, a tobacco article having a multilayer structure can be easily and inexpensively manufactured. Each layer can comprise or be made of any suitable material as a sheet of paper, cardboard, moulded cellulose pulp, plastic or combinations thereof. The cutouts forming said airflow channel can be easily formed on the guiding layer before assembling the layers to form a tobacco article.

Moreover, said airflow channel formed by cutouts in the guiding layer can be difficultly compressed or deformed. Thus, the airflow channel can keep its initial form after insertion the article inside device or any other action of the user on the tobacco article. This form can be optimized to ensure the desired pressure drop.

The layers forming the tobacco article can be glued and/or attached by pressure to each other.

In some embodiments, the guiding layer is sandwiched between two external layers delimiting at least partially said airflow channel. Additionally, each external layer comprises or is formed from a heat conducting material.

Thanks to these features, heat from an external heating element can be transmitted to the external layer(s) by conduction and/or convection. The external layer(s) can further transfer this heat to the tobacco part to generate aerosol.

Alternatively or additionally, at least one external layer can comprise or can form a susceptor. The susceptor can act as a heater when it is placed within a magnetic field. In some embodiments, said airflow channel extends from an air inlet to the distal end of the tobacco article, along the article axis.

Provided with these features, the airflow can enter said airflow channel through the inlet arranged for example close to the proximal end of the tobacco article. Then, the airflow can be guided along this channel until the distal end of the tobacco article in a fluidically separated way from the tobacco part. In other words, said airflow channel is used to guide the airflow inside the tobacco article without being in contact with the tobacco part. The arrangement of the inlet close to the proximal end of the tobacco article is particularly advantageous since in this case, there is no need of a special inlet opening in the heating chamber. The only opening provided by the heating chamber can be thus the opening used to insert partially the tobacco article. Advantageously, when the tobacco article is partially received in the heating chamber, the air inlet is arranged outside the chamber. The heating chamber can present a cup or box shape with a unique opening usable to insert partially the tobacco article. It can has any suitable cross-section like for example a circular, rectangular or oval cross-section.

According to some embodiments, the tobacco article forms a non-cylindrical or flat shape.

This shape of the tobacco article can be particularly advantageous since it allows a very fast pre-heating of the tobacco substrate to generate aerosol, while ensuring a good vapor generation during a vaping phase. In the further description, a flat shape of the tobacco article may signify that at least one cross-sectional dimension of the tobacco article, called hereinafter width, is at least 3 times, advantageously 5 times and preferably 10 times, greater than another cross-sectional dimension of the tobacco article, called hereinafter thickness. Preferably, these dimensions are measured according to perpendicular axes, each of said axes being perpendicular to the article axis.

According to some embodiments, the flat shape of the tobacco article defines at least two narrow lateral walls and two wide lateral walls.

In this case, the flat shape of the tobacco article means that the distance between its narrow lateral walls is at least 3 times, advantageously 5 times and preferably 10 times, greater than the distance between its wide lateral walls. According to some embodiments, said airflow channel extends along a narrow lateral wall of the tobacco part.

This arrangement is particularly advantageous since it allows keeping unchanged the thickness of the tobacco article. In this case, only the width of the tobacco article is slightly increased. This is advantageous when the tobacco article presents for example a flat shape for a better and fast heating of the tobacco part. Additionally, since in some cases, the tobacco article is at least slightly compressed by exerting pressure on its wide lateral walls, an airflow channel arranged along a respective narrow lateral wall can maintain its shape uncompressed.

In some embodiments, the guiding layer defines a central space configured to receive at least partially the tobacco part. In some embodiments, the central space can also be configured to fix the non-tobacco part.

Advantageously, in this case, the guiding layer is used to fix the tobacco part and advantageously, the non-tobacco part inside the tobacco article.

In some embodiments, said airflow channel opens to a gap formed between the distal end of the tobacco article and the first end of the tobacco part.

The gap ensures a smooth transition between said airflow channel fluidically separated from the tobacco part and one or several airflow channels extending through the tobacco part. For example, the airflow channel fluidically isolated from the tobacco part and the channels extending through the tobacco part can be parallel to each other to guide airflow according to opposite directions. In this case, the gap is configured so as to cause a U-turn of the airflow.

According to some embodiments, the guiding layer defines at least two cutouts forming at least partially two separate airflow channels. These separate airflow channels can extend along different sides of the tobacco part.

Thanks to these features, air can be guided inside the tobacco article from two opposite sides. Additionally, the cross-sectional area of each airflow channel can be kept relatively small since the total pressure drop is determined by the sum of these areas. This is particularly advantageous when the tobacco article presents a flat shape. In this case, the airflow channels do not increase its thickness.

In some embodiments, the guiding layer comprises at least two sublayers adjacent to each other and defining one or several cutouts extending each other. These cutouts form one or several airflow channels.

In this case, one or several airflow channels can be formed by several sublayers. Thus, the dimensions of the or each airflow channel can be increased while keeping the guiding layer easy to produce. Particularly, cutouts can be more easily formed in relatively thin sublayers. These sublayers can be then assembled together to form a guiding layer with airflow channels having desired dimensions. These dimensions are adapted to ensure the desired pressure drop.

In some embodiments, the plurality of layers further comprises a support layer supporting several separable parts of the or at least one guiding layer.

Particularly, cutouts can be formed in the guiding layer so as to divide it in separable parts. These separable parts can be arranged on the support layer to form one or several airflow channels. The separable part can be glued and/or fixed by pressure on the support layer.

The present invention also concerns a manufacturing method of a tobacco article for a heat-not-burn aerosol generating device, the tobacco article extending along an article axis between a proximal end and a distal end, and comprising a tobacco part and a nontobacco part.

The method comprises the following steps:

- forming a guiding layer defining a cutout forming at least partially an airflow channel;

- positioning the tobacco part to be fluidically separated from said airflow channel;

- positioning at least one additional layer to assemble the tobacco article.

In some embodiments, the step of positioning the tobacco part comprises positioning it within a central space defined by the guiding layer. In some embodiments, the step of positioning at least one additional layer comprises positioning two external layers by unrolling a strip of material on either side of the guiding layer.

Advantageously, each layer of tobacco article can be formed by unrolling a strip by means of a suitable mechanism. The guiding layer can be formed from a pre-manufactured strip where the necessary cutouts are done. Each external layer can be formed from a continuous strip. After the tobacco part and eventually the non-tobacco part are positioned inside the corresponding central space, the strips corresponding to the external layers can be unrolled on either side of the guiding layer. Then, the structure can be slightly pressed and/or heated to activate the attachment between the layers. Finally, the structure can be cut to form individual tobacco articles.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and its advantages will be better understood upon reading the following description, which is given by way of non-limiting example and which is made with reference to the appended drawings, in which:

- Figure 1 is a perspective view of an aerosol generating system, the aerosol generating system comprising an aerosol generating device and a tobacco article usable with the aerosol generating device;

- Figure 2 is a cross-sectional view of the aerosol generating system of Figure 1 according to plane II where the tobacco article is inserted into the aerosol generating device (the internal structure of the tobacco article being represented without detail);

- Figure 3 is an expanded view of the tobacco article of Figure 1 according to a first embodiment of the invention;

- Figure 4 is a side cross-sectional view of the tobacco article of Figure 3;

- Figure 5 is a view similar to the one of Figure 4 of a tobacco article according to another example of the first embodiment; - Figure 6 is an expanded view of the tobacco article of Figure 1 according to a second embodiment of the invention; and

- Figure 7 is a schematic view showing a manufacturing method of the tobacco article of Figure 1 .

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 an aerosol to a user, including an aerosol for vaping, by means of a heater element explained in further detail below. 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 the heater element for a variable amount of time (as opposed to a metered dose of aerosol), which can be controlled by 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 vapour to be provided (so as to mimic the effect of smoking a conventional combustible smoking article such as a cigarette, cigar or pipe, etc.). The device may include a temperature regulation control to drive the temperature of the heater and/or the heated aerosol generating substance (aerosol pre-cursor) to a specified target temperature and thereafter to maintain the temperature at the target temperature that enables efficient generation of aerosol.

As used herein, the term “aerosol” may include a suspension of vaporizable material as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. Aerosol herein may generally refer to/include a vapour. Aerosol may include one or more components of the vaporizable material. As used herein, the term “vaporizable material” or “precursor” may refer to a smokable material which may for example comprise nicotine or tobacco and an aerosol former. Tobacco may take the form of various materials such as shredded tobacco, granulated tobacco, tobacco leaf and/or reconstituted tobacco. Suitable aerosol formers include: a polyol such as sorbitol, glycerol, and glycols like propylene glycol or triethylene glycol; a non-polyol such as monohydric alcohols, acids such as lactic acid, glycerol derivatives, esters such as triacetin, triethylene glycol diacetate, triethyl citrate, glycerin or vegetable glycerin. In some embodiments, the aerosol generating agent may be glycerol, propylene glycol, or a mixture of glycerol and propylene glycol. The substrate may also comprise at least one of a gelling agent, a binding agent, a stabilizing agent, and a humectant.

GENERAL DESCRIPTION

Figure 1 shows an aerosol generating system 10 comprising an aerosol generating device 11 , also called heat-not-burn aerosol generating device, and an aerosol generating article 12, also called tobacco article 12. The aerosol generating device 11 is intended to operate with the tobacco article 12. In the example of Figure 1 , the tobacco article 12 is extracted from the aerosol generating device 1 1. In the example of Figure 2, the tobacco article 12 is inserted into the aerosol generating device 1 1 .

The tobacco article 12 extends between a proximal end 14 and a distal end 13 along an article axis X. The proximal end 14 is intended to be closer to a user than the distal end 13 when the tobacco article 12 is operated with the aerosol generating device 11 to generate aerosol. The distal end 13 is designed to be received inside the aerosol generating device 11 as it will be explained in further detail below.

As it is shown in Figure 2, the tobacco article 12 comprises a tobacco part 15 and a non-tobacco part 16 arranged along the article axis X. The tobacco part 15 comprises a first end 18 adjacent to or facing the distal end 13 of the tobacco article 12. Particularly, as it will be explained below in reference to different embodiments of the tobacco article 12, the first end 18 of the tobacco part 15 can be adjacent to the distal end 13 of the tobacco article 12 or can be spaced from this distal end 13 to form a gap. The non-tobacco part 16 comprises a second end 19 adjacent to or facing the proximal end 14 of the tobacco article 12, depending on the embodiments. In any case, the first end 18 is closer to the distal end 13 comparing to the second end 19 and the second end 19 is closer to the proximal end 14 comparing to the first end 18.

According to different embodiments, the tobacco article 12 has a generally flat shape. In some embodiments, both tobacco part 15 and the non-tobacco part 16 present a generally flat shape. In this case, the tobacco part 15 and the non-tobacco part 16 can have similar cross-sections having for example substantially the same cross-sectional area. In a variant, the cross-sectional area of the non-tobacco part 16 is greater, at least along at least an axial portion of length, than the cross-sectional area of the tobacco part 15. In some other embodiments, only the tobacco part 15 presents a generally flat shape and the non- tobacco part 16 presents any other suitable shape, for example substantially circular cylindrical shape. The flat shape of the tobacco article 12 forms at least a pair of narrow lateral walls and a pair of lateral wide walls, extending along the tobacco article X. Advantageously, the flat shape of at least the tobacco part 15 has a generally rectangular cross-section so as it is delimited by said pairs of narrow and wide lateral walls.

The tobacco part 15 may for example be slightly longer than the non-tobacco part 16. For example, the length of the tobacco part 15 according to the article axis X may be comprised between 10 and 25 mm, for example, substantially equal to 18 mm. The width and/or the depth of the tobacco part 15 may be substantially equal to or less than respectfully the width and/or the depth of the non-tobacco part 16. The length of the non- tobacco part 16 according to the article axis X may be substantially comprised between 8 and 20 mm, for example be equal to 15 mm. The above-mentioned length values for both tobacco and non-tobacco parts 15, 16 can be selected within a range of +/- 40%, for example. The tobacco part 15 and the non-tobacco part 16 may be fixed one to the other by one or several wrappers as it will be explained in reference to different embodiments of the tobacco article 12.

The non-tobacco part 16 comprises a core intended to act for example as a cooling element to cool slightly the vapour before it is inhaled by the user. The core may comprise for this purpose for example corrugated paper. The core may be formed through an extrusion and/or rolling process into a stable shape. Advantageously, the core is arranged inside the non-tobacco part 16 to be entirely in contact with the internal surface of the wrapper delimiting this non-tobacco part 16. Additionally or alternatively, the core acts as a filter. The core may be formed by a flow guiding element having a corrugated cross- sectional shape. The tobacco part 15 comprises a vaporizable material and is intended to be heated by a heating chamber, as it will be explained in further detail below. The tobacco part 15 may have a corrugated cross-sectional shape.

As it will be explained below in reference to different embodiments, the tobacco article 12 defines an upstream airflow path and a downstream airflow path. The downstream airflow path extends from the distal end 13 to the proximal end 14 in contact with or adjacent to the tobacco part 15 and the non-tobacco part 16. The upstream airflow path extends from an air inlet to the distal end 13 outside the tobacco part 15. The upstream airflow path comprises one or several upstream channels guiding fresh air from the outside of the tobacco article 12 until the tobacco part 15. The downstream airflow path comprises one or several downstream channels guiding aerosol formed further to heating the tobacco part 15. Advantageously, the or each downstream channel extends through both tobacco and non-tobacco parts 15, 16. Additionally, the or each upstream channel is fluidically isolated from the or each downstream channel. As a result, air is forced through the upstream channel and through the downstream channel without possible shortcut from one to the other.

As it will be explained in reference to the embodiments, the tobacco article 12 further comprises a plurality of layers sandwiching at least the tobacco part 15. The layers can also fix the non-tobacco part 16 to the tobacco part 15. For example, the non-tobacco part 16 can also be sandwiched between at least a pair of layers. Among the layers, at least a guiding layer defines a cutout forming at least partially at least one upstream channel. Additionally, the guiding layer can define a frame receiving the tobacco part 15. Among the layers, at least two external layers delimit at least partially said upstream channel. Additionally, each of these external layers can be formed from a heat conducting material.

Referring to Figure 1 , the aerosol generating device 11 comprises a device body 40 extending along a device axis Y between an open end 41 and a closed end 42. The open end 41 is designed to receive at least partially the tobacco article 12, notably the tobacco part 15 of the tobacco article 12. In some embodiments, the aerosol generating device 1 1 may further comprise a mouthpiece designed to be mounted on the open end 41 of the device body 40, for example once the tobacco article 12 is inserted in the device body 40 through the open end 41. In this case, the mouthpiece may for example be designed to receive the non-tobacco part 16. In some other embodiments, no mouthpiece is provided with the device. In this case, the non-tobacco part 16 can act as a mouthpiece or an external mouthpiece can be used.

The device body 40 comprises various internal components of the aerosol generating device 1 1. Particularly, these internal components can comprise in particular a battery, a controller and at least one heating element (e.g., a ceramic or film heater) for heating tobacco article when inserted in a heating chamber, etc. Among these components, only a heating chamber 60 will be explained in further detail in reference to Figure 2. As it is shown in this Figure 2, the heating chamber 60 is adapted to receive and heat the tobacco part 15 of the tobacco article 12. The heating chamber 60 extends according to the device axis Y between an open end 61 adjacent to the open end 41 of the device body 40 and a closed end 62 opposite to the open end 61 . The heating chamber 60 has a cross-sectional shape complementary to the cross-sectional shape of the tobacco part 15 of the tobacco article 11 . For example, when the tobacco part 15 is flat-shaped, the heating chamber 60 has also a flat shape. In this case, the heating chamber 60 can for example be delimited at least by a pair of wide walls and a pair of narrow walls extending parallel to the device axis Y. The heating chamber 60 further includes a heating element powered by the battery in order to heat the tobacco part 15. The heating element can comprise for example one or several resistive elements attached for example to the wide walls of the heating chamber. In one example, a heating element is attached to only one wide wall. In any case, the wide wall(s) can act as heat transferring elements from the heating elements to the tobacco part through the external layers made of a heat conducting material. The wide walls can be thus designed to be in contact with the external layers of the tobacco article 12 to heat them by conduction and in some cases, slightly compress the tobacco part 15 between the wide walls. According to other embodiments, a gap can be formed between the wide walls of the heating chamber 60 and the tobacco article 12 to heat the tobacco part 15 by convection. According to still another embodiment, at least one heating element presents a coil arranged around the heating chamber 60 and designed to heat the tobacco part 15 by induction. In this case, one or several layers can represent a susceptor adapted to be heated by induction. Alternatively or additionally, susceptors can be comprised in the tobacco part 15.

FIRST EMBODIMENT OF THE TOBACCO ARTICLE Figure 3 shows a tobacco article 12 according to a first embodiment. According to this embodiment, the tobacco article 12 comprises a guiding layer 820 and a pair of external layers 821.

The guiding layer 820 presents a frame defining a central space 823 receiving at least the tobacco part 15 of the tobacco article 12. Advantageously, as shown in Figure 3, the central space 823 receives only the tobacco part 15 without the non-tobacco part 16. The non-tobacco part 16 can be fixed to the frame formed by the guiding layer 820 in the extension of the tobacco part 15. For example, the non-tobacco part 16 can be received partially in an opening 824 defined by the guiding layer 820. The tobacco and non-tobacco parts 15, 16 can be affixed together by the external layers 821 sandwiching the guiding layer 820 with the tobacco part 15 received in the central space 823 and the non-tobacco part 16 partially received in the opening 824.

At least one upstream channel forming the upstream airflow path can be formed by the guiding layer 820. For this purpose, the guiding layer 820 according to the first embodiment can comprise one or several sublayers, each sublayer comprises cutouts defining at least partially one or several upstream channels. At least one upstream channel can extend through several sublayers and particularly, through cutouts formed on different sublayers. Each sublayer can be made of paper, cardboard, moulded cellulose pulp, plastic or combinations thereof. The thickness of each sublayer can be comprised for example between 0,3 mm and 0,8 mm, advantageously between 0,45 mm and 0,5 mm.

According to the examples of Figures 3 to 5, the guiding layer 820 comprises two sublayers 820A, 820B. These sublayers 820A, 820B define cutouts forming, in the example of Figures 3 and 4, a pair of upstream channels 832 on each side of the tobacco part 15. These upstream channels 832 can be arranged symmetrically in respect with the tobacco part, as it is better shown in Figure 4. According to the example shown in Figure 5, the sublayers 820A, 820B can form only one upstream channel 832 arranged along one side of the tobacco part 15. The upstream channel 832 of Figure 5 can have a greater cross- sectional area in comparison with the one of Figures 3 and 4. In a general case, the cross- sectional area of the or each upstream channel 832 is calibrated to ensure the desired pressure drop through the tobacco article 12. For example, the channel may have a cross sectional area opening in transversal direction comprised between 0.04 to 0.8 mm² or between 0.1 and 0.6 mm². The or each upstream channel 832 extends between an air inlet 830 and a gap 828 formed by the guiding layer 820 between the first end 18 of the tobacco part 15 and the distal end 13 of the tobacco article 12. Particularly, the or each gap 828 is formed by superposed cutouts of the sublayers 820A, 820B. In the example of Figures 3 and 4, the sublayer 820A comprises lateral cutouts forming lateral portions of the corresponding upstream channels 832 and transversal cutouts forming transversal portions of the corresponding upstream channels 832. The sublayer 820B comprises only transversal cutouts which are superposed at least partially with the transversal cutouts of the sublayer 820A to form the corresponding gap 828. In the example of Figure 5, the sublayer 820A comprises a lateral cutout forming the lateral portion of the upstream channels 832 and a transversal cutout forming the transversal portion of the upstream channels 832. This transversal portion forms the gap 828 extending for example according to the whole width of the tobacco part 15.

The or each gap 828 can for example be arranged in the extension of the corresponding downstream channel formed on the tobacco part 15. The gaps 828 relative to different upstream channels 832 can be separated (as shown in Figure 3) or form a unique chamber. The or each gap 828 is advantageously configured to direct the flow from the corresponding upstream channel 832 to the downstream channels extending through the tobacco part 15, by turning it for example by 180°.

The or each air inlet 830 can be formed by holes in one of the external layers 821 . These holes can be calibrated to ensure the desired pressure drop through the tobacco article 12.

The external layers 821 can comprise at least two separate layers 821 A, 821 B attached to the respective sublayers 820A, 820B of the guiding layer 820 to fix at least the tobacco part 15 in the central space 823. The attachment can be made by glue and/or pressure. Similarly, the sublayers 820A, 820B can be attached between them by glue and/or pressure. In some embodiments, the sheets 821 A, 821 B can also fixe the non-tobacco part 16 in the opening 824 of the guiding layer 820. As previously explained, each external layer 821 A, 821 B can comprise or made of a heat conductive material such as aluminum and/or paper.

SECOND EMBODIMENT OF THE TOBACCO ARTICLE Figure 6 shows a tobacco article 12 according to a second embodiment. This embodiment is similar to the first embodiment, except the features explained below. Similar features will not be explained again.

Particularly, contrary to the previous embodiment, the tobacco article 12 according to the second embodiment comprises a guiding layer 920 defining one or several cutouts forming separable parts. These separable parts are arranged in a same plane. Each separable part can present a single monolayer piece. In other words, contrary to the previous embodiment, the guiding layer 920 does not define a multilayer structure.

In the example of Figure 6, the guiding layer 920 comprises three separable parts: one external part 920A in a form of “II” and two internal parts 920B, 920C in a form of “I”.

Each separable part can for example comprise or be formed from a sheet of paper, cardboard, moulded cellulose pulp, plastic or combinations thereof. The separable parts can have all the same thickness defining thus the thickness of the guiding layer 920. The thickness of the guiding layer 920 in this embodiment can be greater than the thickness of each sublayer 820A, 820B explained in relation with the previous embodiment. Additionally, in some examples, the thickness of the guiding layer 920 according to the second embodiment can be greater than the total thickness of the guiding layer 820 according to the first embodiment.

The separable parts can be laterally attached to each other and/or attached to a same support layer 925 as shown in Figure 6. The separable parts form between them one or several upstream channels 832. Particularly, in the example of Figure 6, one upstream channel 832 is formed between the separable parts 920A and 920B, and another upstream channel 832 is formed between the separable parts 920A and 920C. Advantageously, the or each upstream channel 832 is formed entirely by the guiding layer 920.

In the example of Figure 6, each upstream channel 832 extends from an air inlet 930 arranged on a narrow lateral wall of the tobacco article extending transversally between the external layers 821 A, 821 B. In this case, each air inlet 830 is formed in a lateral opening between the corresponding separable parts of the guiding layer 920.

As in the previous embodiment, the guiding layer 920 defines a central space 923 adapted to receive at least partially the tobacco part 15. In the example of Figure 6, this central space 923 is laterally delimited by the internal separable parts 920B, 920C. Thus, an upstream channel 832 can be formed on either side of the tobacco part 15. The central space 923 can be further delimited by a portion of the external separable part 920A extending transversally in respect with each internal separable part 920B, 920C. Opposite to said portion of the external separable part 920A, the central space 923 can define an open portion. The open portion can be used to fix the non-tobacco part 16 (not shown in Figure 6).

As mentioned above, the support layer 925 can be used to support the guiding layer 920 and notably, the separable parts of this layer 920 to form one or several upstream channels 832. The support layer 925 can present a frame defining a central opening 940 and adapted to receive partially the tobacco part 15. The support layer 925 can comprise or be made of any suitable material as a sheet of paper, cardboard, moulded cellulose pulp, plastic or combinations thereof. The separable parts can be glued and/or fixed by pressure of the support layer 925.

OTHER EMBODIMENTS OF THE TOBACCO ARTICLE

Other embodiments are still possible. These embodiments can comprise any suitable combination of the features disclosed in relation with the previously mentioned embodiments.

MANUFACTURING METHOD

The tobacco article 12 can be manufactured using a manufacturing method explained in reference to Figure 7.

This method comprises an initial step of forming the guiding layer 820, 920 as previously explained.

Particularly, when the guiding layer 820 is provided with at least two sublayers 820A, 820B, each sublayer 820A, 820B can be provided in a form of a strip where sublayers 820A, 820B intended to form different tobacco articles 12 are attached laterally. Each strip is premanufactured to define the necessary cutouts. During the manufacturing, the strips can be unrolled, superposed and eventually attached together. Similarly, when the guiding layer 920 is provided with several separable parts fixed on a support layer 925, the separable parts can be formed on one or several pre-manufactured strips where separable parts intended to form different tobacco articles 12 are attached laterally. For example, as shown in Figure 7, the external parts 920A can form a first strip and the internal parts 920B, 920C can form a second strip interlaced with the first strip. The first and second strips can be pre-manufactured by forming cutouts on a same continuous strip. Similarly, the support layers 920 can be provided in a form of a pre-manufactured strip. Then, as it is shown in Figure 7, the strip defining the support layers 925 can be unrolled and the strip(s) defining the separable parts of the guiding layer 920 positioned and eventually fixed, on it.

During the next step, a tobacco part 15 is positioned inside the central space 823, 923 defined by each guiding layer 820, 920. Advantageously, during the same step, a nontobacco part 16 is also positioned to extend the tobacco part 15.

During the next step, the external layers 821 A, 821 B are positioned on either side of the guiding layer 820, 920 (with or without the support layer 925) to assemble the tobacco article 12. They can for example be positioned simultaneously and then, the tobacco article 12 can be slightly pressed and/or heated to activate the attachment between the layers (glue and/or pressure). The external layers 821 A, 821 B can be provided in a form of continuous strips unrolled on either side of the guiding layer 820, 920 (with or without the support layer 925), as it shown in Figure 7.

During a final step, the obtained structure can be cut to form a plurality of individual tobacco articles 12.

Claims

1. A tobacco article (12) for a heat-not-burn aerosol generating device (1 1 ), the tobacco article extending along an article axis (X) between a proximal end (14) and a distal end (13), and comprising a tobacco part (15) and a non-tobacco part (16) extending along the article axis (X); the tobacco part (15) comprising a first end (18) and the non-tobacco part (16) comprising a second end (19), the first end (18) being adjacent to the distal end (13) or closer to the distal end (13) than the second end (19), the second end (19) being adjacent to the proximal end (14) or closer to the proximal end (14) than the first end (19); the tobacco article (12) further comprising a plurality of layers, the tobacco part (15) being arranged between a pair of layers; wherein the plurality of layers comprises a guiding layer (820; 920) defining a cutout forming at least partially an airflow channel (832) fluidical ly separated from the tobacco part (15).

2. The tobacco article (12) according to claim 1 , wherein the guiding layer (820; 920) is sandwiched between two external layers (821 A, 821 B) delimiting at least partially said airflow channel (832); advantageously, each external layer (821 A, 821 B) comprising or being formed from a heat conducting material.

3. The tobacco article (12) according to claim 1 or 2, wherein said airflow channel (832) extends from an air inlet (830) to the distal end (13) of the of the tobacco article (12), along the article axis (X).

4. The tobacco article (12) according to claims 2 and 4, wherein the air inlet (830) is formed by one or several holes (833) defined by at least one of the external layers (821 A, 821 B) or by a narrow lateral wall of the tobacco article (12) extending transversally between the external layers (821 A, 821 B).

5. The tobacco article (12) according to any one of the preceding claims, wherein the tobacco article (12) defines an upstream airflow path and a downstream airflow path; the downstream airflow path extending from the distal end (13) to the proximal end (13) in contact with the tobacco part (15); the upstream airflow path being formed at least partially by said airflow channel (832).

6. The tobacco article (12) according to any one of the preceding claims, wherein said airflow channel (832) extends along a narrow lateral wall of the tobacco part (15).

7. The tobacco article (12) according to any one of the preceding claims, wherein the guiding layer (820; 920) defines a central space (823; 923) configured to receive at least partially the tobacco part (15); advantageously, the central space (823; 923) being defined by a frame.

8. The tobacco article (12) according to any one of the preceding claims, wherein said airflow channel (832) opens to a gap (828) formed between the distal end (13) of the tobacco article (12) and the first end (18) of the tobacco part (15).

9. The tobacco article (12) according to any one of the preceding claims, wherein the guiding layer (820; 920) defines at least two cutouts forming at least partially two separate airflow channels (832).

10. The tobacco article (12) according to claim 9, wherein said airflow channels (832) extend along different sides of the tobacco part (15).

1 1 . The tobacco article (12) according to any one of the preceding claims, wherein the guiding layer (820) comprises at least two sublayers (820A, 820B) adjacent to each other and defining one or several cutouts extending each other; said cutouts forming one or several airflow channels (832).

12. The tobacco article (12) according to any one of the preceding claims, wherein the plurality of layers further comprises a support layer (925) supporting several separable parts (920A, 920B, 920C) of the or at least one guiding layer (920).

13. The tobacco article (12) according to any one of the preceding claims, wherein the tobacco part (15) has a flat shape.

14. A manufacturing method of a tobacco article (12) for a heat-not-burn aerosol generating device (11 ), the tobacco article (12) extending along an article axis between a proximal end (14) and a distal end (13), and comprising a tobacco part (15) and a nontobacco part (16); the method comprising the following steps:

- forming a guiding layer (820; 920) defining a cutout forming at least partially an airflow channel (832);

- positioning the tobacco part (15) to be fluidically separated from said airflow channel (832);

- positioning at least one additional layer (821 A, 821 B) to assemble the tobacco article (12) so as the tobacco part (15) is arranged between a pair of layers.

15. The manufacturing method according to claim 14, wherein:

- the step of positioning the tobacco part (15) comprises positioning it within a central space (823; 923) defined by the guiding layer (820; 920);

- the step of positioning at least one additional layer (821 A, 821 B) comprises positioning two external layers (821 A, 821 B) to sandwich the guiding layer (820; 920), advantageously by unrolling a strip of material on either side of the guiding layer (820; 920).

16. The manufacturing method according to claim 15, wherein two external layers (821 A, 821 B) delimit at least partially said airflow channel (832).