WO2024089005A1

WO2024089005A1 - Flat-shaped consumable article for an aerosol generating device, and associated aerosol generating assembly and manufacturing method

Info

Publication number: WO2024089005A1
Application number: PCT/EP2023/079577
Authority: WO
Inventors: Tilen CEGLAR; Jaakko MCEVOY; Christoph Lungenschmied
Original assignee: Jt International Sa
Priority date: 2022-10-24
Filing date: 2023-10-24
Publication date: 2024-05-02

Abstract

The present invention concerns a flat-shaped consumable article for an aerosol generating device, the flat-shaped consumable article extending along an article axis (X) and comprising a tobacco substrate (32); the tobacco substrate (32) defining an external surface comprising a plurality of contact zones designed to be in direct or indirect contact with an external heater to heat the tobacco substrate (32) and a plurality of non-contact zones extending between the contact zones; the consumable article is characterized in that at least some of the non-contact zones are coated with a flavouring substance.

Description

Flat-shaped consumable article for an aerosol generating device, and associated aerosol generating assembly and manufacturing method

FIELD OF THE INVENTION

The present invention concerns a flat-shaped consumable article for an aerosol generating device. The present invention also concerns an aerosol generating assembly and a manufacturing method associated to such a flat-shaped consumable article.

Particularly, the aerosol generating assembly according to the invention comprises an aerosol generating device which is configured to operate with the flat-shaped consumable article comprising for example a tobacco substrate able to form aerosol when being heated. Thus, such type of aerosol generating devices, also known as heat-not-burn devices, is adapted to heat, rather than burn 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 is usually comprised in a separate consumable article. Typically, such aerosol substrate 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 by-products 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. Some aerosol generating devices are configured to operate with a particular type of consumable articles defining a flat-shape. Such type of consumable articles presents reduced dimensions while ensuring a good capacity of vapour generating. These consumables articles can also include a flavouring substance for enriching user experience.

However, it was observed that the flavour generation by the existing flat-shaped consumable articles is not completely satisfying. In some cases, the flavour may be too strong or in some other cases, too weak. In particular, the way the flavour is applied should be improved so that its intensity is better mastered and its release more predictable.

SUMMARY OF THE INVENTION

One of the aims of the invention is to provide a flat-shaped consumable article which is able to generate vapour together with a flavour in an optimized way.

For this purpose, the invention relates to a flat-shaped consumable article for an aerosol generating device, the flat-shaped consumable article extending along an article axis and comprising a tobacco substrate; the tobacco substrate defining an external surface comprising a plurality of contact zones designed to be in direct or indirect contact with an external heater to heat the tobacco substrate and a plurality of non-contact zones extending between the contact zones; the consumable article is characterized in that at least some of the non-contact zones are coated with a flavouring substance.

Thanks to the above-mentioned features of the consumable article, the flavouring substance is applied directly on the tobacco substrate. Thus, heating of the tobacco substrate causes flavour releasing and the flavour is mixed evenly with the vapour generated by the tobacco substrate. This ensures a homogeneous flavour taste for the user during the whole vaping session. Additionally, provided with the above-mentioned features, the flavouring substance is not in contact with the external heater so its overheating and in some cases burning can be avoided. This can also elongate the flavour releasing through the whole session in a more even manner, since the heating of the flavour substance is less intense.

The flavouring substance is advantageously a flavour with solvent such as ethanol, water, oil, propylene glycol, hexane, triacetin, and combinations thereof. The flavour may be: natural flavour materials, botanicals, extracts of botanicals, synthetically obtained materials, cooling agent, or combinations thereof. Examples of flavours are: menthol, eugenol, fruit, berry, spices, roots, licorice, etc. The flavour may be releasable upon achieving a temperature suitable for aerosol generation from the tobacco substrate. The flavour may be encapsulated in or coated with a heat degradable or meltable polymer matrix or gel, for example, polysaccharide.

According to some embodiments the non-contact zones are designed to form air gaps with the external heater.

The air gaps can act therefore as a thermal isolator for the external heater so as the flavour overheating or burning can be avoided. In some embodiments, the air gaps can also be used as airflow channels guiding and mixing the vapour generated by the tobacco substrate together with the flavouring substance.

According to some embodiments the non-contact zones form recesses on the external surface of the tobacco substrate and the flavouring substrate is coated at least partially in the recesses.

Thanks to these features, a contact of the flavouring substance with the external heater can be avoided. Moreover, the recess allows the flavour volatiles to expand and flow in the consumable article.

According to some embodiments the contact zones form protrusions on the external surface of the tobacco substrate which are free of flavouring substance.

Thanks to these features, the flavouring substance is coated only at least some of non-contact zones.

According to some embodiments the external surface of the tobacco substrate forms a plurality of airflow channels extending along the article axis.

The airflow channels are thus used to guide vapour generated by the tobacco substrate. The dimensions and the shape of the airflow channels can be chosen so as to ensure a desired pressure drop caused by the consumable article and/or the quantity of the vapour generated by the tobacco substrate.

In some embodiments, the airflow channels can present the same cross-sectional shape and/or dimensions which may be constant along the corresponding channel or may be variable. In some embodiments, the airflow channels can be evenly arranged along the external surface of the tobacco substrate. In some other embodiments, the airflow channels can be arranged unevenly along this external surface. For example, at least one airflow channel can be split on two sub-channels in its downstream section and/or upstream section.

In a general case, the geometry of the airflow channels, their concentration, number and arrangement along the external surface can be determined by a specially designed optimizing method such as described in co-pending EP21204012.5.

According to some embodiments the coated non-contact zones are formed in bottom parts of the airflow channels.

Thanks to these features, contact of the flavouring substance with the external heater can be avoided. Additionally, since the vapour generated by the tobacco substrate flows along the airflow channels, the flavouring substance can be released and evenly mixed with the vapour.

According to some embodiments the external surface of the tobacco substrate forms two opposite lateral surfaces and two opposite wider surfaces extending between the lateral surfaces, the airflow channels extending on both wider surfaces.

Thanks to these features, both surfaces of the flat-shaped consumable article can form airflow channels. This can for example be advantageous when the external heater comprises a pair of heating plates extending according to both sides of the flat-shaped consumable article. In some embodiments, the airflow channels can have the same arrangement and/or geometry on both sides of the flat-shaped consumable article. According to some other embodiments, at least the channels’ geometry or their arrangement may be different. According to some embodiments, the tobacco substrate forms a corrugated shape when viewed in cross-section in the transversal plane perpendicular to the article axis.

Thanks to these features, the airflow channels of one of the surface of the flat-shaped consumable article are in offset in respect with the airflow channels of the other surface. Thus, the tobacco substrate of the flat-shaped consumable article can be easily manufactured using for example an embossing/debossing process of a tobacco sheet.

According to some embodiments, the article further comprises a wrapper wrapping the tobacco substrate and forming gaps with at least some of the non-contact zones and/or being in adjacent contact with the contact zones.

The wrapper avoids condensation of the vapour inside the device, for example inside the heating chamber. Additionally, since according to some embodiments the wrapper covers the airflow channels, the vapour is efficiently conducted inside the airflow channels. The wrapper can be made at least partially of a heat-conductive material, like for example an aluminium foil. The wrapper may be made of both paper and aluminium, for example an outer paper layer and an inner aluminium layer. Preferably, the wrapper is made of a same laminate along the article axis with aluminium and paper. In some embodiments, the wrapper can also assemble the tobacco substrate with a non-tobacco portion, forming for example a cooler and/or filter part of the article. In some embodiments, the wrapper may be interposed between the contact zones of the tobacco substrate and the heater.

The present invention also relates to an aerosol generating assembly comprising:

- an aerosol generating device;

- a flat-shaped consumable article as defined above, the flat-shaped consumable article being designed to operate with the aerosol generating device.

The present invention also relates to a manufacturing method of the flat-shaped tobacco article as defined above, comprising a step of coating of at least some of noncontact zones with the flavouring substance.

Thanks to these features, the flavouring substance can be placed on the non-contact zones of the tobacco substrate. The coating step can be performed according to any suitable process. According to some embodiments, the step of coating is performed by spraying the flavouring substance.

The spraying ensures a very accurate disposing of the flavouring substance on the corresponding surface of the tobacco substrate. Additionally, the spraying intensity can be adjusted so as to ensure the desired thickness of the layer formed by the flavouring substance. In some embodiments, to ensure the desired accuracy, the gap between spraying nozzles and the corresponding surface of the tobacco substrate, as well the spraying angle can be adjusted. This gap can for example be chosen substantially equal to 1 ,7 mm (+/- 10% for example). The spraying angle can for example be chosen substantially equal to 0°. In this case, the spraying is performed substantially perpendicularly to the corresponding surface. Additionally, a shield mounted on each nozzle can be used to prevent any spreading of the spray.

In the embodiments where the flavouring substance is disposed in the airflow channels, a single flavouring substance can be used. Alternatively, a single flavouring substance can be used for a group of channels and another flavouring substance can be used for another group of channels. Thus, different flavouring substances can be sprayed on different groups of channels. For example, a group of channels can be formed by the airflow channels arranged on the same surface of the tobacco substrate and another group can be formed by the airflow channels arranged on the opposite surface.

According to some embodiments the step of coating is performed by a gravure process of the flavouring substance.

The gravure process can advantageously be integrated in a standard manufacturing process of flat-shaped consumable articles by stamping. In this case, the manufacturing installation can be only slightly modified to integrate a coating system including a gravure mechanism, for example between an embossing roller system or moulding system and a cutting system. Thus, the existing installations for manufacturing flat-shaped consumable articles can be easily adapted to manufacture such consumables with a flavouring substance.

In the embodiments where the coating is realized by spraying, the existing manufacturing installations can also be easily adapted to integrate one or several nozzles for spraying the substance in at least some non-contact zones of the substrate. In this case, the nozzles can be arranged after the embossing roller system and in some cases, after the cutting system.

According to some embodiments, the gravure process is carried out by at least:

- a gravure roller rotating in a bath of the flavouring substance and defining nub regions and valley regions;

- a doctor blade cooperating with the gravure roller to remove the flavouring substance from the valley regions.

Thanks to these features, the gravure system can be similar to the embossing roller system. For example, the gravure system can be arranged in series with the embossing roller system so as after the embossing of the tobacco sheet, the gravure with the flavouring substance can be performed in the corresponding non-contact zones. The operation of the embossing roller system and the coating system can be synchronized to fit correctly the non-contact zones formed by the embossing roller system.

According to some embodiments, the method further comprises an embossing step for forming non-contact zones on an external surface of a tobacco sheet and a cutting step for cutting the embossed tobacco sheet to form a plurality of tobacco substrates.

According to some embodiments, the coating step is performed between the embossing step and the cutting step.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and its advantages will be better understood upon reading the following description, which is given byway 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 assembly comprising an aerosol generating device and a consumable article according to the invention, the consumable article being usable with the aerosol generating device;

- Figure 2 is a perspective view of the consumable article of Figure 1 , the consumable article comprising a tobacco substrate; - Figure 3 is a perspective view of the tobacco substrate of Figure 2;

- Figure 4 is a schematic view of an installation suitable for manufacturing the tobacco substrate of Figure 2;

- Figure 5 is a zoom view of element V of Figure 4; and

- Figure 6 is a schematic view of a coating system comprising a plurality of nozzles.

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.

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.

By limitation “direct or indirect contact” applied in relation with an external heater and a first element of the consumable article, it is understood that this first element can form a surface which can be in direct or indirect contact with the external heater. Particularly, no air gap is advantageously formed between the external heater and the first element. In case of an indirect contact, the first element can be separated from the external heater by a second element of the consumable article. This second element presents advantageously a thickness which is less than the thickness of the first element. It can for example be 50%, advantageously 70% and preferably 80% less than the thickness of the first element. Advantageously, the second element is made of at least partially heat conducting material. In some embodiments, the second element is formed by a wrapper.

Figure 1 shows an aerosol generating assembly 10 comprising an aerosol generating device 1 1 and a consumable article 12, according to the invention. The aerosol generating device 1 1 is intended to operate with the consumable article 12 which is shown in more detail in Figure 2.

Referring to Figure 1 , the aerosol generating device 11 comprises a device body 15 extending along a device axis Y. The device body 15 comprises a mouthpiece 16 and a housing 17 arranged successively along the device axis Y. According to the example of Figure 1 , the mouthpiece 16 and the housing 17 form two different pieces. Particularly, according to this example, the mouthpiece 16 is designed to be fixed on or be received in an insertion opening formed at one of the ends of the housing 17. In this case, the consumable article 12 can be inserted inside the device 11 when the mouthpiece 16 is removed from the housing 17. According to another example (not-shown), the mouthpiece 16 and the housing 17 form one unique piece. In this case, the consumable article 12 can be inserted inside the device 11 through for example an outlet hole. According to both examples, the mouthpiece 16 defines a through hole adapted to receive at least partially the consumable article 12. Particularly, the through hole can be adapted to receive at least a mouth end of the consumable article 12, explained in further detail below. According to still another embodiment (not-shown), no mouthpiece 16 is provided with the aerosol generating device 11 . In this case, the mouth end of the consumable article 12 can form a mouthpiece designed to be in contact with the user’s lips and/or mouth while a vaping session.

The housing 17 delimits an internal space of the device 11 receiving various elements designed to carry out different functionalities of the device 1 1. This internal space can for example receive a battery for powering the device 11 , a control module for controlling the operation of the device 11 , a heating chamber for heating the consumable article 12, etc. Particularly, the heating chamber is designed to receive at least partially the consumable article 12. In the example of Figure 1 , the heating chamber may be for example arranged in the extension of the through hole of the mouthpiece 16, according to the device axis Y. The heating chamber may for example present a cup shape and comprises a heater designed to heat at least a part of the consumable article 12. The heater comprises for example a pair of heating plates facing each other and designed to heat opposite walls of the consumable article 12 as it will be explained in further detail below.

In reference to Figure 2, the consumable article 12 is a flat-shaped cuboid extending along an article axis X between an inlet end 18 and a mouth end 19, and having external dimensions LxWxD. In a typical example, the length L of the article 12 according to the article axis X equals substantially to 33 mm while its width W and depth D are substantially equal respectively to 12 mm and 1 ,2 mm. According to different examples, the values L, W and D can be selected within a range of +/- 40%, for example. The depth D of the tobacco article 12 is formed by a pair of parallel walls 23A, 23B, called hereinafter lateral walls 23A, 23B, and the width W of the tobacco article 12 is formed by a pair of parallel walls 24A, 24B, called hereinafter wider walls 24A, 24B. Each wider wall 24A, 24B is for example at least 5 times, advantageously 10 times, wider than each lateral wall 23A, 23B. The flat shape of the consumable article 12 is thus defined by the ratio between each wider wall 24A, 24B and each lateral wall 23A, 23B, which is greater than 5, advantageously greater than 10. In some embodiments, the edges between the wide and lateral walls 23A, 23B, 24A, 24B can be rounded. According to other embodiments of the invention, the tobacco article 12 can have any other suitable flat shape and/or external dimensions.

The tobacco article 12 comprises a substrate part 25 and a cooling and/or filtering part 26 arranged along the article axis X. The substrate part 25 may for example be slightly longer than the cooling and/or filtering part 26. For example, the length L2 of the substrate part 25 according to the article axis X may be substantially equal to 18 mm and the length L1 of the cooling and/or filtering part 26 according to the article axis X may be substantially equal to 15 mm. The substrate part 25 defines the inlet end 18 of the article 12 and the cooling and/or filtering part 16 defines the mouth end 19 of the article 12. The substrate part 25 and the cooling and/or filtering part 26 may be fixed one to the other by a wrapper 31 extending around the article axis X. In this case, the wrapper 31 forms the lateral and wider walls 23A, 23B, 24A, 24B of the consumable article 12. In some embodiments, the wrapper 31 is formed from a same wrapping sheet. In some other embodiments, the wrapper 31 is formed from separate wrapping sheets wrapping separately the parts 25, 26 and fixed one to the other by any other suitable mean. The wrapper 31 may, for example, comprise paper and/or non-woven fabric and/or aluminium foil. The wrapper 31 may be porous or air impermeable. In some embodiments, when the wrapper 31 comprises aluminium, the aluminium can wrap only the tobacco substrate explained in further detail below, to prevent condensation leakage and/or vapour leakage. In an embodiment, the wrapper is a laminate of paper and aluminium which extends along the full length of the article axis X. Additionally, aluminium allows a better heat transfer. In some embodiments, the consumable article 12 can be provided and used without the wrapper 31 .

The part of each wider wall 23A, 23B corresponding to the substrate part 25 of the article 12 is designed to be heated by the heating chamber of the device 11 . Particularly, each of these parts is designed to be in contact with the heating plate forming the heater, as explained above. In some embodiments, the corresponding part of only one of the wider walls 23A, 23B is designed to be heated by the heater.

The cooling and/or filtering part 26 comprises a core 37 intended to act for example as a cooler and/or filter to cool and/or filter the vapour before it is inhaled by the user. The core 37 may comprise for example corrugated paper. The core 37 may be formed through an extrusion and/or rolling process into a stable shape. Advantageously, the core 37 is arranged inside the cooling and/or filtering part 26 to be entirely in contact with the internal surface of the wrapper 31 delimiting this cooling and/or filtering part 26. In some embodiments, no core is provided and the cooling and/or filtering part 26 can for example be hollow. Still according to some other embodiments, no cooling and/or filtering part 26 is provided and the consumable article 12 is formed by the substrate part 25.

The substrate part 25 comprises a tobacco substrate 32 containing a vaporizable material as defined above. The vaporizable material is for example compressed to form a solid structure which is able to release aerosol upon heating.

As shown in Figure 3, the tobacco substrate 32 defines for example a generally flatshaped cuboid defining a pair of opposite lateral surfaces 33A, 33B (represented as the right and left sides of the substrate in Figure 3), and a pair of opposite wider surfaces 34A, 34B (represented as the top and bottom sides in Figure 3), each of said surfaces extending along the article axis X. The lateral surfaces 33A, 33B and the wider surfaces 34A, 34B form an external surface of the substrate 32. When the consumable article is in use in the device, the wider surfaces 34A, 34B are positioned in close contact with the heating elements of the device so as to be heated by the heater element, e.g., with the wrapper positioned in-between. In the embodiments where the consumable article 12 comprises the wrapper 31 , the lateral surfaces 33A, 33B are adjacent at least partially to the internal surface of the lateral walls 23A, 23B formed by the wrapper 31 and the wider surfaces 34A, 34B are adjacent partially to the internal surface of the wide walls 24A, 24B formed by the wrapper 31.

The tobacco substrate 32 further defines a pair of transversal surfaces 36A, 36B (represented as the back and front sides of the substrate in Figure 3) extending transversally to the article axis X. The transversal surface 36A forms the inlet end 18 of the consumable article 12 and the transversal surface 36B is adjacent to the cooling and/or filtering part 26 of the consumable article 12.

At least one of the wider surfaces 34A, 34B, advantageously each wider surface 34A, 34B, of the tobacco substrate 32 defines one or a plurality of grooves extending between the transversal surfaces 36A, 36B. Each groove forms an airflow channel designed to conduct an airflow along the corresponding wider surface 34A, 34B.

Each airflow channel can extend generally along the article axis X which means that the airflow conducted by this airflow channel is mainly directed from the inlet end 18 to the cooling and/or filtering part 26. At least some of the airflow channels can be rectilinear and/or at least some of the airflow channels can be curvilinear. At least some of the airflow channels can present a variable cross-sectional dimension and/or shape along their length. Particularly, the groove’s width and/or depth of forming an airflow channel can vary along the length of this channel. The cross-sectional shape of the groove can also vary. For example, in some cross-sections the groove can have a rounded shape and in some other cross-sections a rectangular shape. The variation of the shape and/or dimensions can be smooth (gradual) or discontinuous. Additionally, at least some airflow channels can be split in two or more sub-channels.

In the example of Figure 3, three airflow channels 40A, 40B are formed on each wider surface 34A, 34B. These airflow channels are rectilinear and define a substantially constant cross-section along their length. Additionally, the airflow channels 40B of the wider surface 34B are in offset in respect with the airflow channels 40A of the wider surface 34A. Thus, in this example, the tobacco substrate 32 defines a corrugated shape when viewed in the transversal plane perpendicular to the article axis X.

The external surface of the tobacco substrate 32 formed the wider surfaces 34A, 34B, comprises a plurality of contact zones designed to be in direct or indirect contact with the heater of the heating chamber and a plurality of non-contact zones extending between the contact zones. The lateral surfaces 33A, 33B may also be in direct or indirect contact with the heater. The contact zones are advantageously arranged on the wider surfaces 34A, 34B and correspond preferably to protruding parts of these surfaces 34A, 34B extending between the air channels. The non-contact zones correspond thus to bottom parts of the airflow channels and to the lateral surfaces 34A, 34B.

In the embodiments where the consumable article 12 is provided with the wrapper 31 , the contact zones are in contact with the internal surface of the wrapper 31 and are thus in indirect contact with the heater. Advantageously, air gaps are formed between the noncontact zones and the wrapper 31 . In the embodiments where the consumable article 12 is provided without the wrapper 31 , the contact zones are advantageously in direct contact with the heater. In both cases, the non-contact zones are not in direct or indirect contact with the heater. Advantageously, air gaps are formed between the non-contact zones and the heater.

According to the invention, at least some of the non-contact zones are coated with at least one flavouring substance. Advantageously, only the non-contact zones of the wider surfaces 34A, 34B are coated with at least one flavouring substance. Thus, in this embodiment, only the bottom parts of the airflow channels are coated with at least one flavouring substance.

The flavouring substance is intended to be released upon heating and/or interaction with the vapour produced by the tobacco substrate 25. The flavouring substance is advantageously a flavour with solvent such as ethanol, water, oil, propylene glycol, hexane, triacetin, and combinations thereof. The flavour may be: natural flavour materials, botanicals, extracts of botanicals, synthetically obtained materials, cooling agent, or combinations thereof. Examples of flavours are: menthol, eugenol, fruit, berry, spices, roots, licorice, etc. The flavour may be releasable upon achieving a temperature suitable for aerosol generation from the tobacco substrate. The flavour may be encapsulated in or coated with a heat degradable or meltable polymer matrix or gel, for example, polysaccharide.

To manufacture a tobacco substrate 32 comprised in the consumable article 12 according to the invention, different manufacturing installations can be used.

An example of such a manufacturing installation 100 is shown in Figure 4. In reference to this Figure 4, the manufacturing installation 100 comprises a receiving mechanism 105, an embossing roller system 110, a coating system 1 15, a cutting system 125 and a delivering mechanism 130.

The receiving mechanism 105, e.g. a hopper, is able to receive a vaporizable material intended to form a tobacco substrate 32, for example in a form of tobacco dough. In some embodiments, the receiving mechanism 105 can be combined with a pre-rolling system that is able to pre-roll the tobacco dough in a lamination device to form a flat sheet. For this purpose, the pre-rolling system may comprise for example a pair of rollers connected to the receiving mechanism 105. The number of pairs of rollers and the spacing between the rollers of each pair may be adapted to the final thickness of the desired sheet. In some other embodiments, the receiving mechanism 105 is directly connected to the embossing roller system 1 10.

The embossing roller system 1 10 comprises for example a pair of embossing rollers 112, 1 14 facing each other. Each embossing roller 112, 1 14 is configured to emboss or deboss a predetermined pattern on the tobacco dough to form at least one tobacco substrate 32 comprising one or several airflow channels, as explained above. Advantageously, each embossing roller 112, 114 is configured to emboss/deboss a plurality of predetermined patterns to form a plurality of tobacco substrates 32. These patterns can be identical or different. In this last case, different airflow channel arrangements can be obtained on different tobacco substrates 32 and/or on different wider surfaces 34A, 34B of a same tobacco substrate 32. Each embossing roller 112, 114 can for example comprise a solid surface (metal or like) where the predetermined pattern(s) is(are) formed using any suitable method (cold spray, SLS, 6-axis CNC, etc.). In the embodiments where only one wider surface 34A, 34B of the tobacco substrates 32 defines airflow channels, one of the embossing rollers 112, 114 can be replaced by a guiding roller.

The tobacco dough may be a substrate containing tobacco particles and/or inhalable agent which contains at least one stimulant, e.g., nicotine and/or flavor, aerosol former, and a gelling agent or binder. The aerosol former may represent 20-70 wt. % in dry basis of the substrate. The gelling agent may represent between 1 -8 wt. % in dry basis. The gelling agent may be guar gum, gellan gum, non-protein polysaccharides and mixtures thereof. The substrate may further comprise a degradation preventing and/or thickening stabilizer such as carboxymethylcellulose. The substrate can be a crumbed tobacco substrate wherein the aerosol releasing substrate has a soft granular texture such as described in WO2021094366. An example of pressed tobacco substrate is described in WO2021094365. The mixture may comprise solid tobacco comminuted to bring them to a particle size (D90) below 300 microns, preferably between 20-220 microns. The tobacco particles may be mixed with aerosol former, the gelling agent, optionally stabilizer and water. A tobacco dough of water content below 50 wt. %, e.g., of about 30-40 % can be obtained. The production of the tobacco dough may be carried out as described in EP 3852554.

In the example of Figure 4, the coating system 1 15 is configured to carry out a gravure process to coat at least some of the non-contacts zones of the tobacco substrate 32. For example, the coating system 115 comprises a pair of gravure rollers 1 16, 117. Each gravure roller 116, 117 is configured to rotate in a bath of the flavouring substance and is associated to a doctor blade 118, 119 configured to remove the flavouring substance from regions of the corresponding gravure roller 116, 117 which are not intended to be in contact with the non-contact zones of the tobacco substrate 32. In other words, each doctor blade 118, 1 19 is configured to remove the flavouring substance from the corresponding gravure roller 116, 117 so as to coat only the non-contact zones of the tobacco substrate 32. For this purpose, each gravure roller 116, 1 17 can comprise a pattern corresponding to the pattern used to form the airflow channels. As it is shown in Figure 5 corresponding to a zoom view of the blade 1 19 cooperating with the gravure roller 117, the pattern of the gravure roller 117 comprises nub regions 120 corresponding to protrusions on its surface and valley regions 121 corresponding to recesses on its surface. The doctor blade 119 has a substantially complementary shape adapted to remove the flavouring substance only from the valley regions 121 and not from the nub regions 120, as it is shown in Figure 5. For this purpose, the protrusions formed on the blade’s surface can be slightly longer than the depth of the valley regions 121 . The difference between this depth and the length of the protrusions on the blade’s surface defines the thickness of the layer of the flavouring substance. In the embodiments where only one wider surface 34A, 34B of the tobacco substrates 32 defines airflow channels, one of the gravure rollers 1 17, 119 can be replaced by a guiding roller. In any case, the operation of the coating system 115 and the embossing roller system 110 is synchronized so as the nub regions 120 of the gravure roller 1 17, 1 19 can fit the airflow channels formed by the embossing rollers 112, 114.

Other embodiments of the coating system 115 are also possible. For example, in some embodiments, the coating system 114 is configured to coat the flavouring substance in the corresponding non-contact zones by spraying it. The spraying can be performed using one or several nozzles, as shown in Figure 6. In case of a plurality of nozzles, different flavouring substances can be used by different nozzles. Thus, at least some non-contact zones of the tobacco substrate 32 can be coated with different flavourings substances. For example, different flavouring substances can be used for different wider surfaces 34A, 34B. Alternatively or additionally, in case of a plurality of nozzles, a nozzle can be associated to each airflow channel 40A, 40B. For example, as it is shown in Figure 6, nozzles 140 can be arranged parallel between them to form a series of nozzles and can spray simultaneously the flowering substance while their movement along the corresponding airflow channels 40A. Another series of nozzles can be provided to spray the flavoring substance in the airflow channels 40B. Alternatively, the tobacco substrate 32 can be moving between two stationary series of nozzles.

In some embodiments, to ensure the desired accuracy of spraying, the gap between the nozzles 140 and the corresponding surface of the tobacco substrate 32, as well the spraying angle can be adjusted. This gap can for example be chosen substantially equal to 1 ,7 mm (+/- 10% for example). The spraying angle can for example be chosen substantially equal to 0°. In this case, the spraying is performed substantially perpendicularly to the corresponding surface, as it shown in both examples A and B of Figure 6. Additionally, as it is shown in example B of Figure 6, a shield 142 mounted on each nozzle 140 can be used to prevent any spreading of the spray.

The cutting system 125 comprises a guiding roller 126 and a cutting roller 127 configured to cut the tobacco sheet with embossed airflow channels to form a plurality of tobacco substrates 32.

The delivering mechanism 130 is configured to deliver the tobacco substrates 32 formed after the cutting. In some cases, it can also be configured to form a wrapper around these substrates 32 and/or assemble these substrates 32 with the cooling and/or filtering part 25 to form flat-shaped consumable articles 12 as explained above.

A manufacturing method of a tobacco substrate 32 is carried out for example by the manufacturing installation 100 of Figure 4. The method comprises an initial step of laminating tobacco dough into a tobacco sheet and a step of embossing/debossing the tobacco sheet with a plurality of patterns corresponding to airflow channel arrangements intended to be formed on the tobacco substrates 32. The method may comprise additionally or alternatively, an extrusion step of the dough through an extruding nozzle. For example, the dough may be extruded into pellets which are then fed to the lamination device such as described in WO2021 144676. This step is performed by the embossing roller system 1 10. Then, the method comprises a step of coating of at least some non-contact zones of the tobacco substrate 32 performed by the coating system 1 15. Depending on different embodiments of the coating system 1 15, the coating can be performed using a gravure process or by spraying the flavouring substance, as explained before. The method further comprises a step of cutting the embossed tobacco sheet to form a plurality of tobacco substrates 32, by the cutting system 125. Finally, the tobacco substrates 32 are delivered by the delivering mechanism 130 and are for example wrapped and/or assembled with the cooling and/or filtering parts, as explained above.

Claims

1. A flat-shaped consumable article (12) for an aerosol generating device (1 1 ), the flat-shaped consumable article (12) extending along an article axis (X) and comprising a tobacco substrate (32); the tobacco substrate (32) defining an external surface comprising a plurality of contact zones designed to be in direct or indirect contact with an external heater to heat the tobacco substrate (32) and a plurality of non-contact zones extending between the contact zones; the consumable article (12) is characterized in that at least some of the non-contact zones are coated with a flavouring substance.

2. The flat-shaped consumable article (12) according to claim 1 , wherein the noncontact zones are designed to form air gaps with the external heater.

3. The flat-shaped consumable article (12) according to any one of the preceding claims, wherein the non-contact zones form recesses on the external surface of the tobacco substrate (32) and the flavouring substrate is coated at least partially in the recesses.

4. The flat-shaped consumable article (12) according to claim 3, wherein the contact zones form protrusions on the external surface of the tobacco substrate (32) which are free of flavouring substance.

5. The flat-shaped consumable article (12) according to any one of the preceding claims, wherein the external surface of the tobacco substrate (32) forms a plurality of airflow channels (40A, 40B) extending along the article axis (X).

6. The flat-shaped consumable article (12) according to claim 5, wherein the coated non-contact zones are formed in bottom parts of the airflow channels (40A, 40B).

7. The flat-shaped consumable article (12) according to claim 5 or 6, wherein the external surface of the tobacco substrate (32) forms two opposite lateral surfaces (33A, 33B) and two opposite wider surfaces (34A, 34B) extending between the lateral surfaces (33A, 33B), the airflow channels (40A, 40B) extending on both wider surfaces (34A, 34B).

8. The flat-shaped consumable article (12) according to any of claims 5 to 7, wherein the tobacco substrate (32) forms a corrugated shape when viewed in cross-section in the transversal plane perpendicular to the article axis (X).

9. The flat-shaped consumable article (12) according to any one of the preceding claims, further comprising a wrapper (31 ) wrapping the tobacco substrate and forming gaps with at least some of the non-contact zones and/or being in adjacent contact with the contact zones.

10. An aerosol generating assembly (10) comprising:

- an aerosol generating device (1 1 );

- a flat-shaped consumable article (12) according to any one of the preceding claims, the flat-shaped consumable article (12) being designed to operate with the aerosol generating device (1 1 ).

11 . A manufacturing method of the flat-shaped tobacco article (12) according to any one of the preceding claims, comprising a step of coating of at least some of non-contact zones with the flavouring substance.

12. The manufacturing method according to claim 11 , wherein the step of coating is performed by spraying the flavouring substance.

13. The manufacturing method according to claim 11 , wherein the step of coating is performed by a gravure process of the flavouring substance.

14. The manufacturing method according to claim 13, wherein the gravure process is carried out by at least:

- a gravure roller (1 16, 117) rotating in a bath of the flavouring substance and defining nub regions (120) and valley regions (121 );

- a doctor blade (118, 1 19) cooperating with the gravure roller (1 16, 1 17) to remove the flavouring substance from the valley regions (121 ).

15. The manufacturing method according to any one of claims 11 to 14, further comprising an embossing step for forming non-contact zones on an external surface of a tobacco sheet and a cutting step for cutting the embossed tobacco sheet to form a plurality of tobacco substrates (32).