Tobacco Article Comprising a Viscous Vaporizable Material and Associated Aerosol Generating Device and Assembling Method

The present invention concerns a tobacco article comprising a viscous vaporizable material. The present invention also concerns an aerosol generating device and an assembling method associated to such a tobacco article.

Different types of aerosol generating devices are already known in the art. Generally, such devices comprise a storage portion for storing a vaporizable material, also known as aerosol forming precursor, which can for example be liquid or solid or even viscous. A heating system is formed of one or more electrically activated resistive elements arranged to heat said precursor to generate the aerosol. The aerosol is released into a flow path extending between an inlet and outlet of the device. The outlet may be arranged in a mouthpiece, through which a user inhales for delivery of the aerosol.

The aerosol generating devices comprise generally a battery able to power the heating system. The powering may be controlled by a control module connecting the heating system to the battery via an electric circuit.

In some aerosol generating devices, the precursor is stored in a removable cartridge. Thus, when the precursor is consumed, the cartridge can be easily removed and replaced.

The cartridges storing a vaporizable material in a liquid form generally comprise a ceramic or cotton wick to deliver the liquid until the heating system. However, such type of wick can be clogged or even burned after a limited number of puffs. In other types of cartridges, a liquid or viscous material can be held in a metal container and heated up using resistive heating. However, in such cartridges, a significant amount of condensation is formed in the mouthpiece that requires a cleaning effort for the consumer. Additionally, a high efficiency of insulation is necessary to avoid too high temperatures of the housing for the consumers.

The present invention aims to avoid these issues and proposes a tobacco article without wick which minimizes condensation in the mouthpiece and avoids overheating of the external housing.

For this purpose, the invention relates to a tobacco article comprising a viscous vaporizable material and a support, the support being formed from one or several rigid sheets arranged or bent to retain the viscous vaporizable material and to form an airflow path.

Particularly, provided with these features, using of a wick can be avoided since the viscous material can be heated directly by a resistive heater or induction to release aerosol into the airflow path. The airflow path can also avoid condensations in the mouthpiece. Additionally, since the vaporizable material can be isolated from the heating chamber by the support and since condensation can be minimized, there is no need for cleaning of the heating chamber even with intensive using.

In the meaning of the invention, the “rigid sheet” signifies that the sheet in the assembled tobacco article cannot be forced out of its shape during a normal usage of the tobacco article. In other words, the rigidity of this sheet allows forming a given shape (for example a cylindrical shape) without losing mechanical integrity and good mechanical contact with neighboring layers.

Advantageously, the viscosity of the vaporizable material is comprised between 45000 mPa·s and 250000 mPa·s and preferably, between 50000 mPa·s and 130000 mPa·s and even more preferably between 55000 mPa·s and 100000 mPa·s. It can for example be substantially equal to 60000 mPa·s. It can be measured using a known viscometer, for example a Brookfield viscometer LVT. The viscosity of the vaporizable material can be chosen as a function of the tobacco content in the vaporizable material. For example, for a smaller content of the tobacco material, a higher viscosity of the vaporizable material may be needed to maintain the desired mechanical integrity.

The Young's modulus of the vaporizable material can be comprised between 5 kPa and 30 kPa, advantageously between 7 kPa and 25 kPa. It can for example be substantially equal to 10 kPa. It can be measured a known tensile tester.

In some embodiments, tobacco content in the vaporizable material can be comprised between 15% and 20%, and advantageously equal for example to 20% or 21%.

According to some embodiments, the or each rigid sheet is made of metal.

Thanks to these features, the support can be heated by an external resistive heater for example by conduction and/or convection, and transmit the received heat directly to the vaporizable material. Thus, efficiency of aerosol generation can be increased.

According to some embodiments, the or each rigid sheet is bent to form a cylindrical shape, advantageously having a circular cross-section.

The cylindrical shape is particularly advantageous since the airflow path can be formed in the center of this shape. Thus, aerosol can be formed by the vaporizable material all around the airflow path and can efficiently be conducted until the mouthpiece.

The cylindrical shape may have any appropriate cross-section. It may for example have a circular, rectangular or square cross-section.

In case of a circular cross-section, the tobacco article can have the same appearance as a conventional cigarette or a stick used with some HNB devices (heat-not-burn devices). Additionally, in some embodiments, the tobacco article can have an elongated shape and even similar dimensions as a conventional cigarette. According to other embodiments, the tobacco article can be more compact than a conventional cigarette. For example, its diameter can be comprised between 4 and 15 mm, advantageously between 5 and 10 mm. It can for example be substantially equal to 6 mm. The length of the tobacco article can also be shortened in comparison with a conventional cigarette. For example, its length can be comprised between 6 mm and 20 mm, advantageously between 10 and 15 mm. It can for example be substantially equal to 12 mm.

According to some embodiments, the tobacco article comprises an outer sheet and an inner sheet, the viscous vaporizable material being retained between said sheets.

Thanks to these features, the viscous vaporizable material can be efficiently retained between the sheets. The vaporizable material is thus sandwiched between the sheets and forms for example a thin tobacco layer. The thickness of the tobacco layer can be comprised between 0.1 and 5 mm, advantageously between 0.5 and 3 mm, and even more advantageously between 0.5 and 2 mm. Thus, the tobacco layer can be heated almost instantly, without needing a special pre-heating phase. Additionally, each rigid sheet can also form a thin layer. Its thickness can for example be comprised between 0.01 and 1 mm, advantageously between 0.05 and 0.5 mm. In some embodiments, this thickness can be substantially equal to 0.1 mm.

According to some embodiments, the inner sheet delimits the airflow path.

The airflow path is thus delimited by one of the rigid sheets and the vaporizable material can entirely surround the airflow path. Provided with these features, aerosol can be formed by the vaporizable material all around the airflow path and can efficiently be conducted until the mouthpiece.

According to some embodiments, the inner sheet is perforated.

Perforations in the inner sheet make it possible aerosol releasing from the vaporizable material directly to the airflow path. The perforations can be arranged along the inner sheet according to any suitable pattern. For example, the perforations can be homogenously distributed along the inner sheet. According to another embodiment, the perforations are mainly distributed in a predetermined portion of the inner sheet. This portion can for example form an upstream portion or a central portion or a downstream portion in respect with the airflow path. The perforations have dimensions which are advantageously comprised between 0.3 mm and 0.7 mm, and preferably substantially equal to 0.5 mm.

According to some embodiments, the tobacco article further comprises a gauze sheet interposed between the vaporizable material and the or at least one of the rigid sheets.

The gauze sheet can prevent against leakages to the exterior of the tobacco article and/or in the airflow path. In the preferred embodiment, the gauze sheet is interposed between the inner sheet and the vaporizable material. The gauze sheet can for example extend according to the whole area of the corresponding rigid sheet. The gauze sheet can also ensure a mechanical support for the vaporizable material. The gauze sheet can be made of or comprise cotton, nylon, glass fiber, cellulose, composite and/or tea bag paper. The tea bag paper may be a blend of wood and vegetable fibers. According to another embodiment, the tea bag paper is a porous element made of paper or possibly polymeric mesh.

According to some embodiments, the tobacco article further comprises an external wrapper assembling the or each rigid sheets with a filter/cooling portion.

Thanks to these features, the aerosol formed by the vaporizable material can be filtered and/or cooled by the filter/cooling portion.

According to some embodiments, the viscous vaporizable material is chosen among at least one of the following elements:

According to some embodiments, the viscous vaporizable material comprises a solid content and a liquid content, the ratio of the solid content being comprised between 80% and 120% of the liquid content and is advantageously equal to 100% of the liquid content.

Thanks to these features, the vaporizable material can form an appropriate viscosity to be retained between the rigid sheets.

According to some embodiments, the solid content comprises ground tobacco.

Thanks to these features, aerosol formed by the vaporizable material can provide a tobacco taste. The proportions of the ground tobacco in the solid content can be comprised between 40% and 60%, and preferably substantially equal to 50%.

According to some embodiments, the liquid content comprises glycerine, preferably propylene glycol and advantageously water.

According to some embodiments:

Thanks to these features, the vaporizable material can generate vapor while being heated. By adapting these ratios within the given intervals, the quantity of the generated vapor can be adjusted during the whole vaping session. Thus, user experience can be improved.

According to some embodiments, said outer sheet forms a unique outer sheet and said inner sheet forms a unique inner sheet of the article.

According to some embodiments, the viscous vaporizable material is in direct contact with the outer sheet.

According to some embodiment, the viscous vaporizable material forms a unique layer of vaporizable material in the article.

The invention also relates to an aerosol generating device comprising a cavity configured to receive and heat the tobacco article as defined above.

According to some embodiments, the cavity is configured to receive and heat simultaneously at least two tobacco articles, the airflow path of one of the tobacco articles extending the airflow path of the other tobacco article.

The tobacco articles can for example be stacked one on the other to form a continuous airflow path. The airflow path can for example extend through the center of the articles. In some embodiments, the articles can provide fixing means making it possible to fix articles between them. The articles can for example be assembled before being inserted in the cavity. Alternatively, the articles can be assembled by their consecutive insertion into the cavity. The fixing means can be configured to prevent aerosol leakage between the articles.

Using of several tobacco articles within a same device can be advantageous when prolonged vapor sessions are needed for the user. In some cases, several articles can be used to adjust their compatibility with different types of aerosol generating devices having different lengths of the cavities.

The invention also relates to an assembling method of a tobacco article as defined above, the method comprising the following steps:

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 aerosol generating unit (e.g. an aerosol generating element which generates vapor which condenses into an aerosol before delivery to an outlet of the device at, for example, a mouthpiece, for inhalation by a user). 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), 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 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.). 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 precursor 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 vapor. Aerosol may include one or more components of the precursor.

As used herein, the term “vaporizable material” or “aerosol-forming precursor” may refer to one or more of a: liquid; solid; gel; mousse; foam or other substances. The vaporizable material may be processable by the heating system of the device to form an aerosol as defined herein. The vaporizable material may comprise one or more of: nicotine; caffeine or other active components. The active component may be carried with a carrier, which may be a liquid. The carrier may include propylene glycol or glycerin. A flavoring may also be present. The flavoring may include Ethylvanillin (vanilla), menthol, Isoamyl acetate (banana oil) or similar. A solid aerosol forming substance may be in the form of a rod, which contains processed tobacco material, a crimped sheet or oriented strips or shreds of reconstituted tobacco (RTB). The vaporizable material can be viscous.

As used herein, the term “length” in relation with an object is used to designate the longitudinal dimension of this object measured according to an extension axis of this object.

shows an aerosol generating setcomprising an aerosol generating deviceaccording to a first embodiment of the invention and a tobacco articleconfigured to operate with the aerosol generating device. The tobacco articleis preferably removable and can be inserted in the deviceand extracted from the deviceas it will be explained in further detail below.