Aerosol-generating items

Abstract

To provide an aerosol-forming substrate equipped with a slender susceptor.SOLUTION: An aerosol generation article (10) is provided with a plurality of elements which are assembled into a rod shape having an end (70) on a mouth side and a distal end (80) upstream of the end on the mouth side. The plurality of elements are provided with an aerosol-forming substrate (20) provided with a slender susceptor (25) arranged in the aerosol-forming substrate in a long axis direction. A plug element (90) is positioned upstream of the aerosol-forming substrate in the rod and adjacent to the same. The plug elements (90) thereby prevent direct physical contact with a distal end of the slender susceptor (25) arranged in a longitudinal axial direction in the aerosol-forming substrate (20).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an aerosol-generating article comprising an aerosol-forming substrate and an elongated susceptor disposed within the aerosol-forming substrate, in particular an inductively heatable aerosol-generating article. [Background technology]

[0002] From the prior art, inductively heatable aerosol-generating articles are known, comprising an aerosol-forming substrate and an elongated susceptor arranged within the aerosol-forming substrate. For example, International Patent Publication WO 2015 / 176898 discloses an aerosol-generating article having an elongated susceptor arranged within an aerosol-forming substrate plug. The aerosol-generating article comprises a plurality of elements in the form of rods and is adapted to be used in an electrically operated aerosol generating device comprising an inductor for generating heat within the elongated susceptor. The position of the elongated susceptor may depend on the manufacturing method of the aerosol-forming substrate comprising the susceptor. However, the elongated susceptor typically extends at least to the distal end of the aerosol-forming substrate plug. This exposed position of at least the end of the susceptor may change the consistency of the article, since the position of the susceptor may change during handling or transport of the article.

[0003] It would therefore be desirable to have an aerosol-generating article that includes an aerosol-forming substrate and an elongated susceptor disposed within the aerosol-forming substrate that improves article consistency. Summary of the Invention

[0004] According to the present invention, there is provided an aerosol-generating article comprising a plurality of elements assembled in the form of a rod having an oral end and a distal end upstream from the oral end. The plurality of elements comprises an aerosol-forming substrate comprising an elongated susceptor longitudinally disposed within the aerosol-forming substrate. A plug element is located within the rod upstream of and adjacent to the aerosol-forming substrate. The plug element prevents direct physical contact with the distal end of the elongated susceptor longitudinally disposed within the aerosol-forming substrate.

[0005] The plug element may prevent direct contact with the distal end of the susceptor and thus prevent the susceptor from shifting or deforming during handling or transport of the article. The susceptor, which is typically a metal component and relatively heavy, tends to fall off the aerosol-forming substrate as the article is transported. Thus, the plug element also prevents the susceptor from falling off the aerosol-generating article, for example if the susceptor becomes dislodged during transport of the article. A further advantage of the plug element protecting the distal end of the aerosol-forming substrate may be for aesthetic or branding reasons. The plug element may be used to cover the distal end of the article. This may provide a good appearance to the distal end of the article. It may also provide information on the article, such as brand, contents, flavor, or electronically operated devices used with the article.

[0006] The plug element may fix the shape and position of the susceptor within the aerosol-forming substrate, thus improving or ensuring article-to-article consistency. In addition, the plug element may also preferably improve the aesthetic appearance of the article and provide an easy way to provide further information about the article to the user.

[0007] As used herein, the terms "upstream" and "downstream" are used to describe the relative positions of elements, or portions of elements, of an aerosol-generating article with respect to the direction in which a user draws on the aerosol-generating article during its use. The aerosol-generating article is in the form of a rod that includes two ends, an oral end (i.e. the proximal end, through which the aerosol exits the aerosol-generating article and is delivered to the user) and a distal end. In use, the user can draw on the oral end. The distal end may also be referred to as the upstream end, and is upstream of the oral end.

[0008] The aerosol-generating article is preferably a smoking article that generates an aerosol.More preferably, the aerosol-generating article is a smoking article that generates a nicotine-containing aerosol.

[0009] The plug element may be a porous element. A porous plug element preferably does not alter the withdrawal resistance of the aerosol-generating article. The plug element preferably has a porosity of at least 50 percent along the longitudinal axis of the rod. The plug element preferably has a porosity of between 50 percent and 90 percent. The porosity along the longitudinal axis of the plug element is defined by the ratio of the cross-sectional area of ​​the material forming the plug element at the location of the plug element to the internal cross-sectional area of ​​the aerosol-generating article. This definition of porosity also applies to any other element of the aerosol-generating article, as appropriate.

[0010] The plug element may be made of a porous material or may include a number of openings, which may be achieved, for example, by laser drilling.

[0011] The permeability of the plug element may allow the user to draw air through the rod via the plug element.

[0012] The plurality of openings are preferably uniformly distributed across the cross section of the plug element.

[0013] The size of the openings of the plurality of openings is preferably such that the distal end of the aerosol-forming substrate is not visible from above.

[0014] The porosity or permeability of the plug element may be varied to accommodate control of the resistance to withdrawal through the aerosol-generating article.

[0015] The resistance to withdrawal (RTD) of the plug element may be between 20 mmWG and 40 mmWG, preferably between 25 mmWG and 35 mmWG (millimeter water gauge). The RTD of the plug element is preferably not more than 30 mmWG. The resistance to withdrawal (RTD) of the plug element is preferably between 1 and 5 mmWG per millimeter of plug element length, for example 2.5 mmWG per millimeter of plug element length. The plug element may have the same RTD as an element made of an aerosol-forming substrate comprising an elongated susceptor.

[0016] Alternatively, the plug element may be airtight and formed of a material that is impermeable to air. In such an embodiment, the article may be configured such that air flows through the sidewalls and into the rod, for example through holes defined in the cigarette paper or wrapper material.

[0017] The plug element may be made of any material suitable for use in an aerosol-generating article for an inductively heatable aerosol-generating device. The plug element may be made of, for example, the same material as used in the article, such as, for example, in a conventional mouthpiece filter, in an aerosol cooling element, or in a support element. Exemplary materials are filter materials, ceramics, polymeric materials, cellulose acetate, cardboard, non-inductively heatable metals, zeolites, or aerosol-forming substrates.

[0018] The plug element is preferably made of a heat resistant material, which in this specification means that the plug element can withstand temperatures up to about 350° C., whereby the plug element is preferably not affected by the heated susceptor or the heated aerosol-forming substrate.

[0019] The plug element preferably does not change in consistency, geometry or optical properties upon use of the article.

[0020] Preferably, during use of the article the plug element does not generate additional material to the generated aerosol.

[0021] The plug element has a diameter approximately equal to the diameter of the aerosol-generating article. The plug element preferably has a diameter between 5 mm and 10 mm. The diameter of the plug is preferably greater than 5 mm, for example between 6 mm and 8 mm. The plug element has a length which may be defined as the dimension along the longitudinal axis of the aerosol-generating article. The length of the plug element may be between 1 mm and 10 mm, for example between 4 mm and 8 mm or between 5 mm and 7 mm. The plug element is preferably substantially cylindrical. The plug element is preferably smaller than 8 mm. The plug element preferably has a length of at least 2 mm, preferably at least 3 mm, or at least 5 mm, to facilitate assembly of the aerosol-generating article.

[0022] In principle, whenever a value is stated throughout this specification, it is understood that the value is expressly disclosed, but it is also understood that the value may not be the exact particular value due to technical considerations.

[0023] The plug elements may be separate elements. The above-mentioned minimum size for the length of the plug elements facilitates or enables the use of conventional combiners to assemble multiple elements into a rod shape.

[0024] The plug element may have a homogenous structure. The plug element may be homogenous, for example, in texture and appearance. The plug element may have, for example, a continuous regular surface across its cross-section, or may have, for example, no discernible symmetry. It is preferred that at least the distal end of the plug element has a homogenous structure. A homogenous distal end of the plug element favors the consistency of the plug element across the cross-section of the article.

[0025] The plug element may have an inner surface defining a recess, the recess being preferably located at least at the proximal end of the plug element. The recess is oriented towards the aerosol-forming substrate. The recess is arranged within the plug element such that the plug element does not contact, or only over a limited area, an elongated susceptor arranged within the aerosol-forming substrate. The recess may be centrally arranged within the plug element such that a central portion of the proximal end of the plug element does not contact the elongated susceptor. The inner surface of the recess may for example have a concave shape, for example a dome-shaped shape. The diameter of the recess in the radial direction of the rod is preferably larger than the radial extension of the elongated susceptor.

[0026] Providing a recess in the plug element so that it does not physically contact the susceptor, and generally limiting the contact area between the plug element and the aerosol-forming substrate, may prevent excessive heating of the plug element (particularly those parts of the plug element that contact the susceptor), thereby reducing the risk of overheating or charring of the plug element and may also broaden the choice of materials suitable for manufacturing the plug element.

[0027] The aerosol-forming substrate may be a solid aerosol-forming substrate. The aerosol-forming substrate may comprise a tobacco-containing material that contains volatile tobacco flavor compounds that are released from the substrate upon heating. Alternatively, the aerosol-forming substrate may comprise a non-tobacco material. The aerosol-forming substrate may further comprise an aerosol former. Examples of suitable aerosol formers are glycerin and propylene glycol.

[0028] When the aerosol-forming substrate is a solid aerosol-forming substrate, the solid aerosol-forming substrate may comprise, for example, one or more of powder, granules, pellets, pieces, spaghetti strands, strips or sheets, including one or more of herb leaves, tobacco leaves, tobacco stem pieces, reconstituted tobacco, homogenized tobacco, extruded tobacco and expanded tobacco. The solid aerosol-forming substrate may be in loose form or may be provided with a suitable container or cartridge. For example, the aerosol-forming material of the solid aerosol-forming substrate may be contained within a paper or other wrapper and have the form of a plug. When the aerosol-forming substrate is in the form of a wrapped plug, the entire plug, including any wrapper, is considered to be the aerosol-forming substrate.

[0029] Optionally, the solid aerosol-forming substrate may contain additional tobacco or non-tobacco volatile flavour compounds which are released upon heating of the solid aerosol-forming substrate. The solid aerosol-forming substrate may also contain capsules, for example containing additional tobacco or non-tobacco volatile flavour compounds, which may dissolve during heating of the solid aerosol-forming substrate.

[0030] The aerosol-forming substrate may comprise one or more sheets of homogenized tobacco material collected into a rod, surrounded by a wrapper and cut to provide individual plugs of aerosol-forming substrate. Preferably, the aerosol-forming substrate comprises an assembly of crimped sheets of homogenized tobacco material.

[0031] The aerosol-forming tobacco substrate is preferably a preferably crimped tobacco sheet comprising tobacco material, fibers, binders, and aerosol formers. The tobacco sheet is preferably a cast leaf. Cast leaf is a form of reconstituted tobacco formed from a slurry containing tobacco particles, fiber particles, aerosol formers, binders, and, for example, flavors.

[0032] The wrapper may be any non-tobacco material suitable for wrapping the elements of an aerosol-generating article in the form of a rod, the wrapper retaining the elements within the aerosol-generating article when the articles are assembled into a rod.

[0033] The aerosol-forming substrate may be substantially cylindrical in shape. The aerosol-forming substrate may be substantially elongated. The aerosol-forming substrate may also have a length and a circumference substantially perpendicular to the length.

[0034] Further, the length of the aerosol-forming substrate may be 10 millimeters. Alternatively, the length of the aerosol-forming substrate may be 12 millimeters. Further, the diameter of the aerosol-forming substrate may be between 5 millimeters and 12 millimeters.

[0035] The term "susceptor" as used herein means a material capable of converting electromagnetic energy into heat. When located in a fluctuating electromagnetic field, eddy currents induced in the susceptor cause the susceptor to heat. The elongated susceptor is in thermal contact with the aerosol-forming substrate, so that the aerosol-forming substrate is heated by the susceptor. The susceptor has a length dimension that is greater than its width dimension or its thickness dimension, for example, a length dimension that is twice its width dimension or its thickness dimension. Thus, the susceptor may be described as an elongated susceptor. The susceptor is substantially longitudinally aligned within the rod. This means that the length dimension of the elongated susceptor is aligned approximately parallel to the longitudinal axis of the rod, for example within ±10 degrees of parallel to the longitudinal axis of the rod. In a preferred embodiment, the elongated susceptor may be positioned at a radially central position within the rod and extends along the longitudinal axis of the rod.

[0036] The susceptor is preferably in the form of a pin, rod, strip or blade. The susceptor is preferably 5 mm to 15 mm, for example 6 mm to 12 mm, or 8 mm to 10 mm in length. The susceptor is preferably 1 mm to 5 mm in width and may be 0.01 mm to 2 mm in thickness, for example 0.5 mm to 2 mm in thickness. In a preferred embodiment, the susceptor may have a thickness of 10 micrometers to 500 micrometers, but even more preferably 10 to 100 micrometers. When the susceptor profile has a constant cross section, for example a circular cross section, it has a preferred width or diameter of 1 mm to 5 mm. When the susceptor has the form of a strip or blade, the width of the strip or blade is preferably 2 mm to 8 mm, more preferably 3 mm to 5 mm, for example 4 mm, and the thickness is preferably 0.03 mm to 0.15 mm, more preferably 0.05 mm to 0.09 mm, for example 0.07 mm, and preferably has a rectangular shape.

[0037] The elongated susceptor preferably has a length that is the same as or shorter than the length of the aerosol-forming substrate.The elongated susceptor preferably has the same length as the aerosol-forming substrate.

[0038] The susceptor may be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from the aerosol-forming substrate. Preferred susceptors include metal or carbon. Preferred susceptors may include or consist of a ferromagnetic material, such as a ferromagnetic alloy, ferritic iron, or ferromagnetic steel, or stainless steel. A suitable susceptor may be or include aluminum. Preferred susceptors may be formed from 400 series stainless steel, such as grade 410, or grade 420, or grade 430 stainless steel. Different materials disperse different amounts of energy when positioned in an electromagnetic field having similar values ​​of frequency and field strength. Thus, any of the parameters of the susceptor, such as the type of material, length, width, and thickness, may be varied to provide a desired power distribution in a known electromagnetic field.

[0039] Preferred susceptors may be heated to temperatures in excess of 250° C. Suitable susceptors may comprise a non-metallic core having disposed thereon a metal layer, e.g., a metal band formed on the surface of the ceramic core. The susceptor may have a protective outer layer, e.g., a protective ceramic layer or a protective glass layer, encapsulating the susceptor. The susceptor may comprise a protective coating formed of glass, ceramic, or an inert metal formed over a core of susceptor material.

[0040] The susceptor is arranged in thermal contact with the aerosol-forming substrate such that as the temperature of the susceptor increases, the aerosol-forming substrate is heated and an aerosol is formed. The susceptor is preferably arranged in direct physical contact with the aerosol-forming substrate, for example within the aerosol-forming substrate.

[0041] The susceptor may be a multi-material susceptor and may include a first susceptor material and a second susceptor material. The first susceptor material is laminated in physical contact with the second susceptor material. The second susceptor material preferably has a Curie temperature below 500° C. The first susceptor material is preferably used primarily to heat the susceptor when it is placed in an oscillating electromagnetic field. Any suitable material may be used. For example, the first susceptor material may be aluminum or a ferrous material such as stainless steel. The second susceptor material is preferably used primarily to indicate when the susceptor has reached a certain temperature, the temperature being the Curie temperature of the second susceptor material. The Curie temperature of the second susceptor material may be used to regulate the temperature of the entire susceptor during operation. Thus, the Curie temperature of the second susceptor material must be below the ignition point of the aerosol-forming substrate. Suitable materials for the second susceptor material can include nickel and certain nickel alloys.

[0042] The heating of the aerosol-forming substrate and the temperature control of the heating can be separated by providing a susceptor having at least a first and a second susceptor material with a second susceptor material having a Curie temperature and a first susceptor material having no Curie temperature, or by providing a first and a second susceptor material having first and second Curie temperatures different from each other. The first susceptor material is preferably a magnetic material having a Curie temperature above 500° C. From the viewpoint of heating efficiency, it is desirable that the Curie temperature of the first susceptor material exceeds any maximum temperature to which the susceptor can be heated. The second Curie temperature can be preferably selected to be lower than 400° C., preferably lower than 380° C., or lower than 360° C. The second susceptor material is preferably a magnetic material selected to have a second Curie temperature that is substantially the same as the desired maximum heating temperature. That is, the second Curie temperature is preferably approximately the same as the temperature to which the susceptor should be heated to generate an aerosol from the aerosol-forming substrate. The second Curie temperature may be, for example, in the range of 200° C. to 400° C., or 250° C. to 360° C. The second Curie temperature of the second susceptor material may be selected such that the overall average temperature of the aerosol-forming substrate does not exceed 240° C. when heated by a susceptor that is, for example, at a temperature equal to the second Curie temperature.

[0043] The aerosol-generating article may be substantially cylindrical in shape. The aerosol-generating article may be substantially elongated. The aerosol-generating article may also have a length and a circumference substantially perpendicular to the length.

[0044] The overall length of the aerosol-generating article may be between 30 mm and 100 mm. In a preferred embodiment, the overall length of the aerosol-generating article is between 40 mm and 55 mm, for example between 47 mm and 53 mm.

[0045] The outer diameter of the aerosol-generating article may be between 5 mm and 12 mm, for example between 6 mm and 8 mm. In one preferred embodiment, the aerosol-generating article has an outer diameter of 7.2 mm ±10 percent.

[0046] The aerosol-generating article may comprise a mouthpiece element, which may be located at the mouth end or downstream end of the aerosol-generating article.

[0047] The mouthpiece element may comprise at least one filter segment. The filter segment may be a cellulose acetate filter plug made of cellulose acetate tow. The filter segment may have low or very low particle filtration efficiency. The filter segment may be longitudinally spaced from the aerosol-forming substrate. The filter segment is 7 millimeters long in one embodiment, but may have a length between 5 millimeters and 14 millimeters.

[0048] The mouthpiece element is the downstream last part of the aerosol-generating article. A user contacts the mouthpiece element to direct the aerosol generated by the aerosol-generating article through the mouthpiece element to the user. Thus, the mouthpiece element is located downstream of the aerosol-forming substrate.

[0049] The mouthpiece element preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article. The mouthpiece element may have an outer diameter of between 5 millimeters and 10 millimeters, for example between 6 millimeters and 8 millimeters. In a preferred embodiment, the mouthpiece element has an outer diameter of 7.2 mm ±10 percent. The mouthpiece element may have a length of between 5 millimeters and 25 millimeters, preferably between 10 millimeters and 17 millimeters. In a preferred embodiment, the mouthpiece element has a length of between 12 mm and 14 mm. In a preferred embodiment, the mouthpiece element has a length of 7 mm.

[0050] The aerosol-generating article may be located immediately downstream of the aerosol-forming substrate and may comprise a support element which may be adjacent to the aerosol-forming substrate.

[0051] The support element may be formed from any suitable material or combination of materials. For example, the support element may be formed from one or more materials selected from the group consisting of cellulose acetate, cardboard, crimped paper (such as crimped heat-resistant paper or crimped parchment paper), and polymeric materials (such as low-density polyethylene (LDPE)). In a preferred embodiment, the support element is formed from cellulose acetate.

[0052] The support element may comprise a hollow tubular element, hi a preferred embodiment, the support element comprises a hollow cellulose acetate tube.

[0053] The support element preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article.

[0054] The support element may have an outer diameter of 5 millimeters to 12 millimeters, for example, 5 mm to 10 mm or 6 mm to 8 mm. In a preferred embodiment, the support element has an outer diameter of 7.2 mm ±10 percent. The support element may have a length of 5 millimeters to 15 millimeters. In a preferred embodiment, the support element has a length of 8 mm.

[0055] The aerosol-generating article may comprise an aerosol cooling element. The aerosol cooling element may be located downstream of the aerosol-forming substrate, for example the aerosol cooling element may be located immediately downstream of and adjacent to the support element.

[0056] The aerosol cooling element may be located between the support element and a mouthpiece element located at the extreme downstream end of the aerosol-generating article.

[0057] As used herein, the term "aerosol cooling element" is used to describe an element having a large surface area and low draw resistance. In use, the aerosol formed by the volatile compounds released from the aerosol-forming substrate is drawn through the aerosol cooling element before being conveyed to the mouth end of the aerosol-generating article. In contrast to filters with high draw resistance (e.g., filters formed from bundles of fibers), the aerosol cooling element has a low draw resistance. Chambers and recesses within the aerosol-generating article, such as expansion chambers and support elements, are also not considered to be aerosol cooling elements.

[0058] The aerosol cooling element preferably has a longitudinal porosity of greater than 50 percent. The airflow path through the aerosol cooling element is preferably relatively unrestricted. The aerosol cooling element may be a sheet assembly or a crimped sheet assembly. The aerosol cooling element may comprise a sheet material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose acetate (CA), and aluminum foil, or any combination thereof.

[0059] In a preferred embodiment, the aerosol cooling element comprises an assembly of biodegradable sheets of material, for example, an assembly of sheets of non-porous paper or a biodegradable polymeric material such as polylactic acid or Mater-Bi® grades (a commercially available family of starch-based copolyesters).

[0060] The aerosol cooling element preferably comprises an assembly of sheets of PLA, more preferably an assembly of crimped sheets of PLA. The aerosol cooling element may be formed from a sheet having a thickness of 10 micrometers to 250 micrometers (e.g., 50 micrometers). The aerosol cooling element may be formed from a sheet assembly having a width of 150 millimeters to 250 millimeters. The aerosol cooling element may have a specific surface area of ​​300 square millimeters to 1000 square millimeters per millimeter of length and 10 square millimeters to 100 square millimeters per millimeter of weight. In some embodiments, the aerosol cooling element may be formed from a sheet assembly of material having a specific surface area of ​​about 35 square millimeters per millimeter of weight. The aerosol cooling element may have an outer diameter of 5 millimeters to 10 millimeters, e.g., 7 millimeters.

[0061] In some preferred embodiments, the length of the aerosol cooling element is between 10 millimeters and 15 millimeters. Preferably, the length of the aerosol cooling element is between 10 millimeters and 14 millimeters, for example 13 millimeters.

[0062] In an alternative embodiment, the length of the aerosol cooling element is between 15 mm and 25 mm. Preferably, the length of the aerosol cooling element is between 16 mm and 20 mm, for example 18 mm.

[0063] As the aerosol passes through the aerosol cooling element, the temperature of the aerosol decreases due to the transfer of thermal energy to the aerosol cooling element. In addition, water droplets liquefied from the aerosol may be adsorbed onto the material of the aerosol cooling element. Depending on the type of material forming the aerosol cooling element, the water content of the aerosol may be reduced by 0 to 90 percent. For example, when the aerosol cooling element includes polylactic acid, the water content is not reduced significantly. For example, when a starch-based material (e.g., Mater-Bi, etc.) is used to form the aerosol cooling element, the reduction in water may be about 40 percent. Thus, the selection of the material forming the aerosol cooling element can determine the water content in the aerosol.

[0064] For example, aerosols formed by heating tobacco-derived aerosol-forming substrates typically contain phenolic compounds. Aerosol cooling elements can reduce the levels of phenol and cresol by 90 to 95 percent.

[0065] Commonly available electronic heating devices are designed to use aerosol-generating articles of certain dimensions, in particular of certain standard lengths. In order for the aerosol-generating article to be usable with these standard heating devices, the overall length of the aerosol-generating article should be of standard length. Typically, such standard length is 45 millimeters. Furthermore, it is preferred that the dimensions and arrangement of the aerosol-forming substrate provided within the aerosol-generating article and heated by the heating element of the heating device remain unchanged.

[0066] Thus, when a plug element is added to an aerosol generating device, the length of the article is increased by the length of the plug element. Thus, the length of the plug element should not exceed 8 mm in length so that the overall length of the aerosol generating article is not unduly extended. Preferably, an aerosol generating article having a standard length of 45 mm will become an article having a length of 47 mm to 53 mm when provided with a plug element.

[0067] However, the length of the article may be kept constant by compensating for the added length of the plug element through shortening of another element or segment of the article (preferably the aerosol cooling element), although doing so preferably does not change the properties of the article.

[0068] Experiments have shown that in standard length aerosol-generating articles, the desired aerosol cooling or reduction of phenolic compounds can be achieved with aerosol cooling elements having lengths shorter than the standard 18 millimeter aerosol cooling elements, and in particular, comparable cooling or different smoke chemistry has been found with shorter aerosol cooling elements made of polylactic acid.

[0069] Thus, the additional length of the plug element is compensated for by a shortening of the aerosol cooling element. The shortening of the aerosol cooling element, or a further shortening of the aerosol cooling element, can also be achieved by providing a hollow tube.

[0070] Some materials used in aerosol-generating articles are also more cost-sensitive than others. For example, materials used in aerosol cooling elements, especially crimped polylactic acid sheets, are expensive. Thus, in an aerosol-generating article, the length of the aerosol cooling element may be reduced compared to such elements in standard aerosol-generating articles for electronic devices. Typically, the standard length of an aerosol cooling element is 18 millimeters. To maintain the overall length of the aerosol-generating article at a given length (e.g., 45 millimeters), the length of the mouthpiece element may be increased to compensate for the shorter length of the aerosol cooling element.

[0071] It has been surprisingly found that the aerosol cooling element can be shortened to some extent without adversely affecting the chemistry of the smoke. It has also been surprisingly found that this can be done without altering the movement of smoke constituents through the mouthpiece, when the difference in length is compensated for within the mouthpiece. In particular, when a hollow tube is used to compensate for the overall length, no change in smoke constituents through the mouthpiece has been detected. It has been found that shortening the aerosol cooling element by just a few millimeters can lead to significant cost savings. The extension of the mouthpiece is preferably achieved by providing a hollow tube. A hollow tube (e.g. a cardboard tube) may be manufactured at very low cost, such that cost savings can be achieved by partially "replacing" the aerosol cooling element in the tobacco portion of the aerosol-generating article with a hollow tube in the mouthpiece portion of the aerosol-generating article.

[0072] Thus, the mouthpiece element may comprise a hollow tube.

[0073] When present, the hollow tube is preferably located at the downstream end of the mouthpiece element and thus the downstream end of the aerosol-generating article, thereby providing the aerosol-generating article with the effect of a recessed filter, thereby providing a customer with a tactile sensation when using the electronic smoking system that is equivalent to the tactile sensation provided by a recessed filter that can be obtained when smoking a conventional cigarette.

[0074] The hollow tube of the mouthpiece element may be made of cardboard. The hollow tube may also be made of different materials (e.g., paper or thin plastic sheet material). It is preferred that the hollow tube has stability to allow handling of the aerosol-generating article.

[0075] The length of the hollow tube may be between 3 mm and 8 mm. Preferably, the length of the hollow tube is 5 mm.

[0076] The lengths of the hollow tubes mentioned above, particularly the cardboard tube lengths, have been found to allow good manufacture of the tube and good handling of the tube during assembly of the mouthpiece element and the aerosol-generating article.

[0077] The wall thickness of the hollow tube is preferably between 100 micrometers and 300 micrometers, for example 200 micrometers. When inserting the aerosol-generating article into the electronic heating device, the consumer typically holds the aerosol-generating article at its proximal end or pushes the aerosol-generating article at its proximal end. The hollow tube is preferably the most proximal segment of the aerosol-generating article, and thus the aerosol-generating article is typically pushed with the hollow tube. The above mentioned wall thicknesses have been found to meet the stability requirements for hollow tubes, particularly cardboard tubes, when the aerosol-generating article is inserted into the electronic heating device.

[0078] The aerosol-generating article according to the invention preferably comprises a plug element, an aerosol-forming substrate including a susceptor, a support element, an aerosol cooling element and a mouthpiece element. The mouthpiece element comprises at least one filter element and may optionally comprise a hollow tube. In such an aerosol-generating article, the support element is arranged downstream of the aerosol-forming substrate and the aerosol cooling element is arranged downstream of the support element.

[0079] In an aerosol-generating article according to the invention comprising a mouthpiece element comprising a filter segment and a hollow tube, the hollow tube is preferably arranged at the distal end of the rod. The mouthpiece element may be extended in length, in particular by adding or extending the hollow tube, to compensate for the shortened length of the aerosol cooling element so that the overall length of the aerosol-generating article is kept at a predetermined overall length. It is preferred that the overall length of the article is 45 mm and that the length of the aerosol cooling element of the tobacco element is at most 15 mm. The length of the mouthpiece element, preferably the length of the hollow tube, is adapted according to the length of the aerosol cooling element so that the overall length of the aerosol-generating article is kept at a predetermined overall length.

[0080] The possibility of having a shortened aerosol cooling element, the supplementation of such a shortened aerosol cooling element by the provision of an additional hollow tube in the mouthpiece element, its advantages and specific features are described in detail in European Patent Application No. 15173224.5, the contents of which, with regard to the aforementioned supplementation of length, are incorporated herein by reference.

[0081] Preferably, the aerosol-generating article comprises five to six elements or segments.

[0082] The elements of the aerosol-forming article, such as the aerosol-forming substrate, the plug element and any other elements of the aerosol-generating article (such as the support element, the aerosol cooling element, and the mouthpiece element), are surrounded by an outer wrapper. The outer wrapper may be formed from any suitable material or combination of materials. The outer wrapper is preferably cigarette paper.

[0083] The invention will be further explained with reference to embodiments, which are illustrated by the following drawings, in which: [Brief description of the drawings]

[0084] [Figure 1] FIG. 1 is a schematic diagram of a cross-section of an embodiment of an aerosol-generating article with a plug element. [Diagram 2] FIG. 2 is a schematic diagram of a cross-section of another embodiment of an aerosol-generating article with a recessed filter. [Diagram 3] FIG. 3 shows a close-up of the recessed plug element. [Figure 4] FIG. 4 shows another embodiment of a plug element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0085] FIG. 1 illustrates an aerosol-generating article 10. The aerosol-generating article 10 includes five coaxially aligned elements: a plug element 90, an aerosol-forming substrate 20, a support element 30, an aerosol-cooling element 40, and a mouthpiece 50. Each of the five elements is a substantially cylindrical element, each having substantially the same diameter. The five elements are arranged in series and surrounded by an outer wrapper 60 to form a cylindrical rod. A blade-shaped susceptor 25 is located within the aerosol-forming substrate and in contact with the aerosol-forming substrate. The susceptor 25 has a length approximately the same as the length of the aerosol-forming substrate and is located along the radial center axis of the aerosol-forming substrate.

[0086] The susceptor 25 is a ferritic iron material having a length of 10 mm, a width of 3 mm and a thickness of 1 mm. One or both ends of the susceptor may be sharpened or pointed to facilitate insertion into the aerosol-forming substrate.

[0087] The aerosol-generating article 10 has a proximal or oral end 70 which a user inserts into his or her mouth during use, and a distal end 80 which is at the opposite end of the aerosol-generating article 10 to the oral end 70. The assembled aerosol-generating article 10 has an overall length of about 47 mm to 53 mm and a diameter of about 7.2 mm.

[0088] During use, air is drawn by a user through the aerosol-generating article from the distal end 80 to the oral end 70. The distal end 80 of the aerosol-generating article may also be described as the upstream end of the aerosol-generating article 10, and the oral end 70 of the aerosol-generating article 10 may also be described as the downstream end of the aerosol-generating article 10. Elements of the aerosol-generating article 10 located between the oral end 70 and the distal end 80 may be described as being upstream of the oral end 70, or alternatively, downstream of the distal end 80.

[0089] The plug element 90 is located at the distal-most or upstream end 80 of the aerosol-generating article 10. In Figure 1, the plug element is shown as a hollow tube, such as a hollow cellulose acetate tube. The inner diameter of the hollow tube is the same as or slightly smaller than the width of the susceptor 25 to prevent the susceptor from becoming dislodged from the distal end of the aerosol-forming substrate 20.

[0090] The aerosol-forming substrate 20 is located immediately downstream of the plug element 90 within the aerosol-generating article 10. In Figure 1, the aerosol-forming substrate 20 comprises an assembly of a crimped, homogenized sheet of tobacco material surrounded by a wrapper. The crimped sheet of homogenized tobacco material contains glycerin as an aerosol former.

[0091] The support element 30 is located immediately downstream of and adjacent to the aerosol-forming substrate 20. In Fig. 1, the support element 30 is a hollow cellulose acetate tube. The support element 30 positions the aerosol-forming substrate 20 within the aerosol-generating article 10. The support element 30 thus helps to prevent the aerosol-forming substrate 20 from being pushed downstream within the aerosol-generating article 10 towards the aerosol cooling element 40, for example, when the article is inserted into a device. The support element 30 also acts as a spacer to space the aerosol-cooling element 40 of the aerosol-generating article 10 from the aerosol-forming substrate 20.

[0092] The aerosol cooling element 40 is located immediately downstream of and adjacent to the support element 30. In use, volatile material emitted from the aerosol-forming substrate 20 passes along the aerosol cooling element 40 towards the mouth end 70 of the aerosol-generating article 10. The volatile material may cool within the aerosol cooling element 40 to form an aerosol that is inhaled by a user. In Figure 1, the aerosol cooling element comprises an assembly of crimped sheets of polylactic acid surrounded by a wrapper 90. The assembly of crimped sheets of polylactic acid defines a plurality of longitudinal channels that extend along the length of the aerosol cooling element 40.

[0093] Mouthpiece 50 is located immediately downstream of and adjacent to aerosol cooling element 40. In Figure 1, mouthpiece 50 includes a conventional cellulose acetate tow filter with low filtration efficiency.

[0094] To assemble the aerosol-generating article 10, the five cylindrical elements described above are aligned and intimately wrapped within an outer wrapper 60. In Figure 1, the outer wrapper is a conventional cigarette paper.

[0095] Once the article is manufactured, the four elements, excluding the plug element 90, may be assembled. The susceptor 25 is then inserted into the distal end 80 of the assembly so as to penetrate the aerosol-forming substrate 20. The plug element 80 is then aligned with the assembly and the five elements are then wrapped with the wrapper 60 to form the complete aerosol-generating article 10. As an alternative method of assembly, the susceptor 25 is inserted into the aerosol-forming substrate 20 before assembling the elements to form the rod.

[0096] The aerosol-generating article 10 of FIG. 1 is designed to engage an electrically operated aerosol-generating device that includes an induction coil (or inductor) for smoking or consumption by a user.

[0097] 2 illustrates an aerosol-generating article 1 comprising six elements, where the same reference numbers are used for the same or similar elements. The plug element 91, the aerosol-forming substrate 20, the support element in the form of a hollow cellulose acetate tube 30, the aerosol cooling element 40, the mouthpiece filter 50 and the cardboard tube 56 are arranged consecutively and coaxially side-by-side and assembled by cigarette paper and by tipping paper (not shown) to form a rod. The cardboard tube 56 is located at the mouth end 70 of the aerosol-generating article 1 and the plug element 91 is located at the distal end 80 of the aerosol-generating article 1.

[0098] When assembled, the rod may have a length 15 of, for example, 45 millimeters and an outer diameter of approximately 7.2 millimeters.

[0099] The plug element 91 is a porous plug, for example a plug of open-pored heat-resistant material. The plug element has a length 95 of 3-5 mm.

[0100] The aerosol-forming substrate 20 may comprise a bundle of crimped cast leaf tobacco wrapped with filter paper (not shown) to form a plug. The cast leaf tobacco contains additives including glycerin as an aerosol-forming additive. The length 25 of the aerosol-forming substrate is 12 millimeters. The length of the susceptor 25 is approximately 10 mm and is pointed at its proximal end.

[0101] The hollow acetate tube 30 is located immediately downstream of and adjacent to the aerosol-forming substrate 20. The length 35 of the acetate tube 30 is 8 mm.

[0102] The aerosol cooling element 40 has a length 45 between 10 mm and 13 mm and an outer diameter of about 7.12 mm. The aerosol cooling element 40 is preferably formed from a sheet of polylactic acid having a thickness of 50 mm ± 2 mm. The sheet of polylactic acid is crimped and assembled to define a plurality of channels extending along the length of the aerosol cooling element 40. The total surface area of ​​the aerosol cooling element may be between 300 mm 2 and 1000 mm 2 per mm of length of the aerosol cooling element 40, or between about 10 mm 2 and 100 mm 2 per mg of weight of the aerosol cooling element 40.

[0103] The length 45 of the aerosol cooling element 40 is 5 mm to 8 mm shorter than conventional aerosol cooling elements for aerosol-generating articles having a standard length of 45 mm. The length of conventional aerosol cooling elements for aerosol-generating articles of such standard length, in particular aerosol cooling elements made of polylactic acid sheets, is 18 mm.

[0104] Mouthpiece filter 50, located downstream of aerosol cooling element 40, may be a conventional mouthpiece filter formed from cellulose acetate and has a length 55 of 7 millimeters.

[0105] The cardboard tube 56 is the most downstream element of the aerosol-generating article 1 and has a length 57 of 3 to 5 mm. The cardboard tube together with the plug element 80 compensates for the shorter aerosol cooling element 50 so that the overall length of the aerosol-generating article is 45 mm. The cardboard tube 56 also provides a recessed mouth end 70 of the aerosol-generating article that mimics the use of a conventional cigarette with a recessed mouth end.

[0106] The shortened length of the aerosol cooling element 40 may compensate for the additional length 95 of the plug element 91 alone. A cardboard tube 56 may optionally be provided.

[0107] In Figure 3, the plug element 92 comprises a recess 920 with an open end directed towards the aerosol-forming substrate 20. The recess 920 is dome-shaped and has a maximum depth 921 that is 25 to 50 percent of the length 95 of the plug element. If the plug element has a length 95 of 5 mm, the depth 921 of the recess 920 is about 1 to 2.5 mm. The material of the plug element 92 is a heat-resistant material that can withstand temperatures of about 350°C. The plug element is preferably porous to allow air to pass through the plug element 92.

[0108] 4 illustrates an embodiment of a plug element 93 having an opening 930 disposed longitudinally within the plug element for air to pass therethrough. The plug element material may be otherwise airtight. The opening 930 has an irregular star-shaped cross section, which may serve marking purposes and aid in the aesthetic appeal of the aerosol-generating article.

Claims

1. 1. An aerosol-generating article comprising a plurality of elements assembled in the form of a rod having an oral end and a distal end upstream from the oral end, the plurality of elements comprising: an aerosol-forming substrate having an elongated susceptor disposed longitudinally within the aerosol-forming substrate; a support element located immediately downstream of the aerosol-forming substrate, the support element being formed from a polymeric material; a plug element located within the rod upstream of and adjacent to the aerosol-forming substrate and the elongated susceptor to prevent the elongated susceptor from dislodging from the aerosol-forming substrate, the plug element being formed from a polymeric material and having a longitudinally disposed opening for air to pass through the plug element; An aerosol-generating article comprising:

2. The aerosol-generating article of claim 1 , wherein the plug element and the support element are made of the same material.

3. 2. The aerosol-generating article of claim 1, wherein the plug element has a resistance to withdrawal (RTD) of between 20 mmWG and 40 mmWG.

4. 2. The aerosol-generating article of claim 1, wherein the plug element is airtight.

5. An aerosol-generating article according to any one of claims 1 to 4, wherein at least the distal end of the plug element has a homogenous structure.

6. 6. An aerosol-generating article according to any one of claims 1 to 5, wherein the plug element comprises an inner surface defining a recess.

7. 7. The aerosol-generating article of claim 6, wherein the inner surface of the cavity has a concave shape.

8. An aerosol-generating article according to any one of claims 1 to 7, wherein the plug element is made of a heat-resistant material.

9. An aerosol-generating article according to any one of claims 1 to 8, wherein the plug element is a separate element.

10. 10. An aerosol-generating article according to any one of the preceding claims, wherein the plug element has a length of between 1 millimetre and 10 millimetres.

11. An aerosol-generating article according to any one of the preceding claims, wherein the aerosol-forming substrate comprises an assembly of sheets of homogenised tobacco material.

12. 12. The aerosol-generating article of claim 1, wherein the plurality of elements further comprises an aerosol cooling element and a mouthpiece element.

13. 13. The aerosol-generating article of claim 12, wherein the mouthpiece element comprises a hollow tube and a filter segment disposed at a downstream end of the mouthpiece element.

14. 13. The aerosol-generating article of claim 12, wherein the aerosol cooling element has a length of up to 15 millimeters.

15. 15. An aerosol-generating article according to any one of claims 1 to 14, wherein the elongated susceptor has the same length as the aerosol-forming substrate.

16. 16. An aerosol-generating article according to any preceding claim, wherein the elongated susceptor has a width of between 1 mm and 5 mm.

17. 17. The aerosol-generating article of any one of the preceding claims, wherein the elongated susceptor has a thickness of from 10 micrometers to 500 micrometers.

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