KR20240101853A - Aerosol-generating article having an aerosol-generating substrate surrounded by a highly porous annular portion - Google Patents

Abstract

An aerosol-generating article (10) for generating an inhalable aerosol when heated includes an aerosol-generating rod (12) extending from an upstream end to a downstream end; and a downstream section (14) provided downstream of the aerosol-generating rod (12) and abutting the downstream end of the aerosol-generating rod (12). The aerosol-generating rod 12 comprises a substantially cylindrical core portion 20 having a longitudinal axis and an annular portion 24 surrounding the core portion 20 and extending coaxially therewith. The annular portion is permeable to air such that the upstream end of the annular portion is in fluid communication with the downstream section 14. Core portion 20 includes an aerosol-generating substrate and has a cross-sectional porosity of 0.10 to 0.45. The cross-sectional porosity of the annular portion 24 is at least 120% of the cross-sectional porosity of the core portion 20.

Description

Aerosol-generating article having an aerosol-generating substrate surrounded by a highly porous annular portion

The present invention relates to an aerosol-generating article comprising an aerosol-generating substrate and configured to generate an inhalable aerosol upon heating.

Aerosol-generating articles in which an aerosol-generating substrate, such as a tobacco-containing substrate, is heated without combustion are known in the art. Typically, in such heated smoking articles, aerosols are generated by heat transfer to an aerosol-generating substrate or material that is physically separate from the heat source, and such substrate or material is located in contact with the heat source, is located inside the heat source, or It may be located around the heat source or downstream of the heat source. During use of the aerosol-generating article, volatile compounds are released from the aerosol-generating substrate by heat transfer from the heat source and are entrained into the air drawn through the aerosol-generating article. As the released compounds cool, they condense and form an aerosol.

A number of prior art documents disclose aerosol-generating devices for consuming aerosol-generating articles. Such devices include, for example, electrically heated aerosol-generating devices in which aerosols are generated by heat transfer from one or more electrical heater elements of the aerosol-generating device to the aerosol-generating substrate of the heated aerosol-generating article. For example, an electrically heated aerosol-generating device has been proposed comprising internal heater blades adapted to be inserted within an aerosol-generating substrate. As an alternative, an inductively heatable aerosol-generating article comprising an aerosol-generating substrate and a susceptor arranged within the aerosol-generating substrate was proposed by WO 2015/176898. A further alternative is described in WO 2020/115151, which discloses an aerosol-generating article used in combination with an external heating system comprising one or more heating elements arranged around the periphery of the aerosol-generating article. For example, the external heating element may be provided in the form of a flexible heating foil on a dielectric substrate such as polyimide.

Aerosol-generating articles in which the tobacco-containing substrate is heated rather than combusted present a number of problems not encountered in conventional smoking articles. First, the tobacco-containing substrate is typically heated to a significantly lower temperature compared to the temperature reached by the combustion front in a conventional cigarette. This can affect the release of nicotine from the tobacco-containing substrate and the delivery of nicotine to the consumer. Additionally, it may be difficult to homogeneously heat the entire tobacco-containing substrate provided within the article.

In aerosol-generating systems, where heat is supplied internally, for example through a heater element inserted into a rod of the aerosol-generating substrate, it may be difficult for the heat supplied by the heater element to be transferred completely efficiently to the periphery of the rod. On the other hand, in an aerosol-generating system in which heat is supplied externally, for example by inserting an aerosol-generating article into a cavity of a heating device comprising one or more heater elements arranged around the side wall of the cavity, the heat supplied by the heater elements is applied to the load. It can be difficult to convey it fully efficiently to the core of .

Difficulties in transferring heat efficiently may result in portions of the rod of the aerosol-generating substrate being unable to reach sufficient temperatures to promote the release of aerosol species. As a result, these portions of the rod of aerosol-generating substrate may not contribute substantially to the overall aerosol delivery of the aerosol-generating article, and thus the efficiency of use of the aerosol-generating substrate provided on the rod may undesirably be less than ideal.

Difficulties in transferring heat efficiently also lead to a portion of the load of aerosol-generating substrate actually reaching temperatures sufficient to promote the release of aerosol species, but only over a small portion of the use cycle of the aerosol-generating article. You can. In these parts of the rod of the aerosol-generating substrate, the temperature profile during use may differ from the intended temperature profile, and thus the aerosol-generating substrate may be undesirably underused.

The problem discussed above is that, regardless of whether a particular model of aerosol-generating article and aerosol-generating device are designed to be used together, there is no market for the aerosol-generating article if the aerosol-generating article is compatible with the size—i.e., diameter—of the aerosol-generating article. It can be further complicated by the fact that it can potentially be heated in any aerosol-generating device available in. One of these potential inconsistencies in aerosol-generating articles and devices, possibly in combination with non-ideal airflow mechanisms through the system during use, can cause the aerosol-generating substrate to be exposed to suboptimal temperature profiles. This can undesirably affect aerosol delivery and temperature, and can change the conditions of use of the system for those for which it is generally intended.

Accordingly, a need is generally felt for an aerosol-generating article that can be adapted to solve one or more of the aforementioned problems. Additionally, it would be desirable to provide aerosol-generating articles that can be easy to manufacture and make the entire production chain more sustainable and cost-effective. Accordingly, it would be desirable to provide new and improved aerosol-generating articles tailored to achieve at least one of the foregoing needs. It would also be desirable to provide such aerosol-generating articles that can be manufactured efficiently and at high rates.

The present disclosure relates to aerosol-generating articles for generating an inhalable aerosol when heated. The aerosol-generating article may include an aerosol-generating rod extending from an upstream end to a day end. The aerosol-generating article may further comprise a downstream section provided downstream of the aerosol-generating rod. The downstream section may border the downstream end of the aerosol-generating rod. The aerosol-generating rod may include a substantially cylindrical core portion having a longitudinal axis and an annular portion surrounding the core portion and extending coaxially with the core portion. The annular portion may be air permeable. The annular portion may be in direct fluid communication with the downstream section. The core portion may include an aerosol-generating substrate. The core portion may have a cross-sectional porosity of 0.10 to 0.45. The cross-sectional porosity of the annular portion may be at least 120% of the cross-sectional porosity of the core portion.

The present disclosure also relates to an aerosol-generating system comprising an aerosol-generating article as described above and an aerosol-generating device comprising a heating chamber open at the proximal end to at least partially receive an aerosol-generating rod for heating the aerosol-generating substrate. . The aerosol-generating device may include an opening at the distal end to allow airflow into the heating chamber along the longitudinal axis of the heating chamber. The diameter of the opening may be smaller than the inner diameter of the annular portion.

According to the invention, an aerosol-generating rod extends from an upstream end to a downstream end; and a downstream section provided downstream of the aerosol-generating rod and bordering the downstream end of the aerosol-generating rod. The aerosol-generating rod includes a substantially cylindrical core portion having a longitudinal axis and an annular portion surrounding the core portion and extending coaxially with the core portion. The annular portion is permeable to air such that the upstream end of the annular portion is in fluid communication with the downstream section. The core portion includes an aerosol-generating substrate and has a cross-sectional porosity of 0.10 to 0.45; The cross-sectional porosity of the annular portion is at least 120% of the cross-sectional porosity of the core portion.

According to the present invention, there is provided an aerosol-generating system comprising an aerosol-generating article and an aerosol-generating device as described above. The aerosol-generating device includes a heating chamber open at the proximal end to at least partially receive the aerosol-generating rod for heating the aerosol-generating substrate. The aerosol-generating device includes an opening at the distal end to allow airflow into the heating chamber along the longitudinal axis of the heating chamber. The diameter of the opening is smaller than the inner diameter of the annular portion.

Accordingly, the aerosol-generating article according to the invention provides a novel configuration of sections of the aerosol-generating article configured to generate an aerosol when heated. More specifically, a substantially cylindrical core portion is provided that contains an aerosol-generating substrate and is surrounded by an air-permeable annular portion having a relatively high cross-sectional porosity. The annular portion is sized so that direct fluid communication can be established between the annular portion and the downstream section.

Because the annular portion is air permeable and has a significantly higher cross-sectional porosity compared to the core portion, the resistance to draw (RTD) of the annular portion is substantially lower than the RTD of the core portion. Accordingly, if the aerosol-generating article is not paired with an aerosol-generating device, air drawn into the aerosol-generating article by the consumer may flow primarily, but not entirely, through the annular portion and around the core portion. Accordingly, the aerosol-generating substrate within the core portion may be substantially bypassed by this air flow. As such, if a consumer inhales through an aerosol-generating article when the aerosol-generating article is not paired with an aerosol-generating device, the functionality of the aerosol-generating article may be substantially disabled.

This is advantageous in that it generally prevents misuse of aerosol-generating articles. For example, attempts on the part of the consumer to use the aerosol-generating article as a conventional combustible smoking article will generally not be successful because the airflow into the core portion at the upstream end of the aerosol-generating article will be insufficient to sustain combustion. .

Additionally, as the aerosol-generating substrate is concentrated in the core of the aerosol-generating rod, - as discussed in more detail below - in systems where heat is supplied internally to the aerosol-generating article, homogeneous heat is achieved for all aerosol-generating substrates during use. Supply can be advantageously facilitated. Since the annular portion surrounding the core portion is not intended to contribute to aerosol generation, heat supply to the annular portion is not important at all. The fact that the air-permeable annular portion is less likely to heat up in systems where heat is supplied internally to the aerosol-generating article may even be advantageous, since in certain embodiments the annular portion may act to some extent as an insulating sleeve. .

Additionally, the core portion and the annular portion may be dimensioned such that the aerosol-generating article is compatible only with use with aerosol-generating devices of a particular design such that when the aerosol-generating article is coupled with the aerosol-generating device, the upstream end of the annular portion is occluded. On the other hand, at the same time, airflow into the core part becomes possible. In contrast, if the aerosol-generating article is combined with a faulty aerosol-generating device, the upstream end of the core portion is at least partially occluded, while at the same time allowing airflow into the annular portion, making use of the aerosol-generating article virtually impossible. do.

For example, in a system according to the invention, an opening may be provided at the distal end of the aerosol-generating device to allow the flow of air into a heating chamber in which the aerosol-generating article is housed. By ensuring that the diameter of the opening is smaller than the inner diameter of the annular part, it is advantageously possible to ensure full use compatibility between the aerosol-generating article and the aerosol-generating device.

This has the advantage of ensuring that only the use of a corresponding dedicated aerosol-generating device and aerosol-generating article will be fully functional and that the aerosol-generating substrate will undergo a predetermined heating profile specifically designed for that aerosol-generating substrate. On the other hand, improper matching of an aerosol-generating article with any aerosol-generating device other than that for which the aerosol-generating article is intended will generally be ineffective. Therefore, mismatching of the aerosol-generating article and the aerosol-generating device is not recommended, while at the same time ensuring that aerosol delivery and other parameters can be optimized when the aerosol-generating article is correctly paired with the intended aerosol-generating device.

As briefly described above, in accordance with the present invention, there is provided an aerosol-generating article for generating an inhalable aerosol when heated. The aerosol-generating article includes an aerosol-generating rod extending from an upstream end to a downstream end. The core portion of the aerosol-generating rod contains an aerosol-generating substrate.

The term “aerosol-generating article” is used herein to refer to an article in which an aerosol-generating substrate is heated to generate an inhalable aerosol and deliver it to the consumer. As used herein, the term “aerosol-generating substrate” refers to a substrate that, when heated, is capable of releasing volatile compounds to generate an aerosol.

Conventional cigarettes are lit when the user applies a flame to one end of the cigarette and draws air through the other end. The local heat provided by the flame and the oxygen in the air drawn through the cigarette cause the tip of the cigarette to ignite, and the resulting combustion produces inhalable smoke. In contrast, in heated aerosol-generating articles, the aerosol is generated by heating a flavor-generating substrate, such as tobacco. Known heated aerosol-generating articles include, for example, electrically heated aerosol-generating articles and aerosol-generating articles in which an aerosol is generated by heat transfer to an aerosol-forming material that is physically separated from a combustible fuel element or heat source. For example, the aerosol-generating article according to the invention finds particular application in aerosol-generating systems comprising an electrically heated aerosol-generating device with internal heater blades adapted to be inserted into a rod of an aerosol-generating substrate. Aerosol-generating articles of this type are described in the prior art, for example in EP 0822670.

As used herein, the term “aerosol-generating device” refers to a device that includes a heater element that interacts with the aerosol-generating substrate of an aerosol-generating article to generate an aerosol.

As used herein in connection with the present invention, the term 'rod' is used to refer to a substantially circular element of substantially circular, oval or elliptical cross section.

As used herein, the term “longitudinal” refers to the direction corresponding to the major longitudinal axis of the aerosol-generating article extending between the upstream and downstream ends of the aerosol-generating article. As used herein, the terms “upstream” and “downstream” describe the relative position of an element, or a portion of an element, of an aerosol-generating article with respect to the direction in which an aerosol is transported through the aerosol-generating article during use.

During use, air is drawn longitudinally through the aerosol-generating article. The term “transverse” refers to the direction perpendicular to the longitudinal axis. Any reference to a “cross-section” of an aerosol-generating article or a component of an aerosol-generating article refers to a cross-section unless otherwise noted.

The term “length” refers to the dimension of a component of an aerosol-generating article in the longitudinal direction. For example, it can be used to indicate the dimensions of a rod or elongated tubular element in the longitudinal direction.

The aerosol-generating article further comprises a downstream section at a location downstream of the aerosol-generating rod. As will become apparent from the following description of different embodiments of the aerosol-generating article of the invention, the downstream section may include one or more downstream elements.

In some embodiments, the downstream section may comprise a hollow section between the aerosol-generating rod and the mouth end of the aerosol-generating article. The hollow section may include hollow tubular elements.

As used herein, the term “hollow tubular segment” or “hollow tubular element” is used to refer to a generally elongated element that defines a lumen or airflow passage along its longitudinal axis. In particular, the term "tubular" hereinafter refers to an element or segment defining at least one airflow conduit having a substantially cylindrical cross-section and establishing unobstructed fluid communication between the upstream end of the tubular element and the downstream end of the tubular element. will be used However, it will be appreciated that alternative geometries (eg, alternative cross-sectional shapes) of the tubular elements or segments may be possible.

In the context of the invention, hollow tubular segments or hollow tubular elements provide an unrestricted flow channel. This means that the hollow tubular segment or hollow tubular element provides negligible resistance to draw (RTD). The term “negligible RTD” means less than 1 mm H ₂ O per 10 mm of the length of the hollow tubular segment or hollow tubular element, preferably 0.4 mm H ₂ O per 10 mm of the length of the hollow tubular segment or hollow tubular element. Used to describe an RTD of less than, more preferably less than 0.1 mm H ₂ O per 10 mm of the length of the hollow tubular segment or hollow tubular element.

Therefore, the flow channel must be free of any components that would impede the flow of air in the longitudinal direction. Preferably, the flow channel is substantially empty.

In this specification, a “hollow tubular segment” or “hollow tubular element” may be referred to as a “hollow tube” or “hollow tube segment.”

In some embodiments, the aerosol-generating article can include a ventilation zone at a location along the downstream section. More specifically, the aerosol-generating article may, in certain embodiments, include ventilation zones at locations along the hollow tubular element. In this way, fluid communication is established between the flow channel defined internally by the hollow tubular element and the external environment.

In the aerosol-generating article according to the invention, the length of the aerosol-generating rod may be at least 5 mm. Preferably, the length of the aerosol-generating rod is at least 10 mm. More preferably, the length of the aerosol-generating rod is at least 12 mm. Even more preferably, the length of the aerosol-generating rod is at least 15 mm.

Preferably, the length of the aerosol-generating rod is 45 mm or less. More preferably, the length of the aerosol-generating rod is 40 mm or less. Even more preferably, the length of the aerosol-generating rod is 40 mm or less.

In a preferred embodiment, the length of the aerosol-generating rod is preferably 35 mm or less. More preferably, the length of the aerosol-generating rod is 30 mm or less. Even more preferably, the length of the aerosol-generating rod is 25 mm or less. In a particularly preferred embodiment, the length of the aerosol-generating rod is 22 mm or less.

In some embodiments, the length of the aerosol-generating rod is 10 mm to 45 mm, preferably 10 mm to 40 mm, more preferably 10 mm to 35 mm, even more preferably 10 mm to 30 mm. In a particularly preferred embodiment, the length of the aerosol-generating rod is between 10 mm and 25 mm, preferably between 10 mm and 22 mm.

In another embodiment, the length of the aerosol-generating rod is 12 mm to 45 mm, preferably 12 mm to 40 mm, more preferably 12 mm to 35 mm, even more preferably 12 mm to 30 mm. In a particularly preferred embodiment, the length of the aerosol-generating rod is between 12 mm and 25 mm, preferably between 12 mm and 22 mm.

In a further embodiment, the length of the aerosol-generating rod is between 15 mm and 45 mm, preferably between 15 mm and 40 mm, more preferably between 15 mm and 35 mm, even more preferably between 15 mm and 30 mm. In a particularly preferred embodiment, the length of the aerosol-generating rod is between 15 mm and 25 mm, preferably between 15 mm and 22 mm.

As briefly explained above, in the aerosol-generating article according to the invention, the aerosol-generating rod comprises a core portion having a longitudinal axis. Preferably, the core portion has a substantially uniform cross-section along the length of the aerosol-generating rod. Particularly preferably, the core portion has a substantially circular cross-section, so that the core portion can be described as substantially cylindrical.

The core portion contains an aerosol-generating substrate and has a cross-sectional porosity of 0.10 to 0.45.

As used herein, the term “porosity” refers to the air permeability or fraction of void space in a porous body. More specifically, the term “porosity” refers to the “cross-sectional porosity” of one such body, i.e. in the cross-sectional area of an air-permeable or porous body, for example in the cross-section of the cylindrical core portion of the aerosol-generating rod in the aerosol-generating article according to the invention. is used herein with reference to the fraction of empty space. Cross-sectional porosity is the area fraction of empty space in the transverse cross-sectional area of the cylindrical core portion. The transverse cross-sectional area of the cylindrical core portion is the area of the cylindrical core portion in a plane perpendicular to the longitudinal axis of the aerosol-generating rod.

As used herein, the term "porosity distribution value" or "cross-sectional porosity distribution value" means a porosity value determined locally within each of a plurality of equal-dimensional sub-regions of a transverse cross-sectional area of an air-permeable or porous body. Indicates the standard deviation of . The porosity within a subregion may be referred to as “local porosity” and the cross-sectional porosity distribution value is the standard deviation of the local porosity values over the transverse cross-sectional area of the air permeable or porous body.

Subarea refers to an area smaller than the transverse cross-sectional area of the body. A plurality of sub-regions of equal dimensions cover the entire transverse cross-sectional area of the body. Preferably, each sub-region overlaps at least one adjacent sub-region, preferably more than one adjacent sub-region. Preferably, each sub-region overlaps by 10% to 95% with at least one adjacent sub-region. Preferably, each sub-region is less than 20% of the total transverse cross-sectional area, for example less than 15% of the total transverse cross-sectional area, preferably less than 10% of the total transverse cross-sectional area.

In the case of a cylindrical body, such as the core portion of an aerosol-generating rod in an aerosol-generating article according to the invention, the transverse cross-sectional area will be substantially circular. Each sub-region is preferably rectangular or square. The sub-regions overlap at least 50% of the transverse cross-sectional area before being included in the calculation of the porosity distribution, particularly preferably at least 70% or at least 80% or at least 90% of the transverse cross-sectional area before being included in the calculation of the porosity distribution. It is desirable to be

Then, as described in more detail below, in certain preferred embodiments wherein the aerosol-generating substrate comprises a sheet of aerosol-forming material gathered to form a core portion, the cross-sectional porosity of the core portion is determined by the diameter of the core portion and the aerosol-forming material. is a function of the width and thickness of the sheet. In this embodiment, the cross-sectional porosity of the core portion can be calculated using the equation:

here,

P _cross = cross-sectional porosity

D _cp = diameter of core section

W _sheet = width of the sheet corrugated to form the core part

T _sheet = thickness of the sheet corrugated to form the core part

The cross-sectional porosity distribution value refers to a measure of the variation in local porosity across different sub-regions of the transverse cross-sectional area of the body.

Accordingly, the cross-sectional porosity distribution value is a quantitative measure of the distribution of porosity across the transverse region of the article. The local porosity of each sub-region may be calculated using the equation below;

here:

P _local = cross-sectional porosity of the subregion

A _local = area of subarea

A _sheet = area of tobacco material within subarea

The cross-sectional porosity distribution value can be found as a measure of the uniformity of porosity of a body, such as a cylindrical body. For example, if the standard deviation of local porosity is low, then the voids within the cylindrical body may be uniformly distributed over the entire transverse area of the cylindrical body and may have similar sizes. However, if the standard deviation is high, then the voids are not distributed uniformly over the transverse area of the cylindrical body, with some sections of the cylindrical body having high porosity and some having low porosity. For a given cross-sectional porosity, a large cross-sectional porosity distribution value may indicate that the cylindrical body has a small number of relatively large through channels, whereas a small cross-sectional porosity distribution value may indicate that the cylindrical body has a large number of relatively small through channels. can indicate that

The cross-sectional porosity distribution value can be determined from local porosity values calculated for a number of sub-regions covering the transverse cross-section of the cylindrical body. The cross-sectional porosity distribution values for any individual rod can be compared to other individual bodies. Alternatively, the cross-sectional porosity distribution value can be calculated from local porosity values derived, for example, from a set or arrangement of multiple different bodies, for example cylindrical bodies, of approximately the same cross-sectional area and approximately the same cross-sectional porosity. there is. Cross-sectional porosity distribution values from a batch of bodies can be used to evaluate the quality of porosity between one batch of bodies and another batch of cylindrical bodies, such as cylindrical bodies.

Advantageously, the transverse cross-sectional porosity and cross-sectional porosity distribution values may be determined using a digital imaging process. An image of a transverse cross-section of the core portion can be acquired, and a threshold can be applied to distinguish pixels representing the aerosol-forming substrate from pixels representing empty space. Subsequently, the porosity of the entire cross section can be easily obtained.

Preferably, the cross-sectional porosity distribution value is determined by obtaining a digital image of a transverse cross-sectional area of the rod, determining the area fraction of empty spaces existing in each of a plurality of sub-regions of the same dimension in the transverse area, Obtaining a porosity value for each of the sub-regions of and calculating a standard deviation of the porosity values for each of a plurality of sub-regions of the same dimension. Each sub-region overlaps with at least one adjacent sub-region by 10% to 95%, preferably 75% to 85%, preferably about 80%.

The core portion is substantially cylindrical and has an average diameter, for example about 4.5 mm. Preferably, each of the sub-regions is rectangular or square with a length of 1/4 to 1/8 the diameter of the core portion, preferably about 1/6 or 1/7 the diameter of the core portion. Accordingly, if the diameter of the core portion is about 4.5 mm, the subregions may be squares with side lengths of about 0.75 mm.

The porosity value of any individual sub-region is only included in the calculations for assessing the porosity distribution, preferably if more than 90% of that sub-region is within the transverse cross-sectional area of the core portion.

Preferably, the digital image of the horizontal cross-sectional area consists of a plurality of pixels, and all pixels constituting the horizontal cross-sectional area are included in at least one of the plurality of sub-regions.

Additional details regarding the determination of porosity or cross-sectional porosity and cross-sectional porosity distribution in air-permeable bodies can be found in the publication of international patent application WO 2016/023965 in the name of the applicant.

Preferably, in the aerosol-generating article according to the invention, the core portion has a cross-sectional porosity of at least 0.15. More preferably, in the aerosol-generating article according to the invention, the core portion has a cross-sectional porosity of at least 0.20.

Preferably, the core portion has a cross-sectional porosity of less than 0.40. More preferably, the core portion has a cross-sectional porosity of less than 0.35. Even more preferably, the core portion has a cross-sectional porosity of less than 0.25.

In some embodiments, the core portion has a cross-sectional porosity of 0.15 to 0.40, preferably 0.15 to 0.35, more preferably 0.15 to 0.25. In another embodiment, the core portion has a cross-sectional porosity of 0.20 to 0.40, preferably 0.20 to 0.35, more preferably 0.20 to 0.25.

The core portion may have a cross-sectional porosity distribution value of at least 0.04, as calculated using the method described above, wherein each sub-region is a square with side lengths one-seventh of the diameter of the core portion. , and each subarea overlaps with at least one other subarea by about 80%. Preferably, the core portion may have a cross-sectional porosity distribution value of at least 0.10, as calculated using the method described above, wherein each sub-region has a side length equal to 1/7 of the diameter of the core portion. It is a square of length, and each subarea overlaps at least one other subarea by about 80%.

The core portion may have a cross-sectional porosity distribution value of less than or equal to 0.22, as calculated using the method described above, in which case each subregion is a square with side lengths of 1/7 of the diameter of the core portion, and each The subarea overlaps approximately 80% with at least one other subarea. Preferably, the core portion may have a cross-sectional porosity distribution value of less than or equal to 0.20, as calculated using the method described above, wherein each sub-region has a side length of 1/7 of the diameter of the core portion. It is square, and each subarea overlaps at least one other subarea by about 80%. More preferably, the core portion may have a cross-sectional porosity distribution value of less than or equal to 0.15, as calculated using the method described above, wherein each sub-region has a side length of 1/7 of the diameter of the core portion. It is a square with each subarea overlapping with at least one other subarea by about 80%.

In some embodiments, the core portion may have a cross-sectional porosity distribution value of 0.04 to 0.22, preferably 0.04 to 0.20, more preferably 0.04 to 0.15. In another embodiment, the core portion may have a cross-sectional porosity distribution value of 0.10 to 0.22, preferably 0.10 to 0.20, more preferably 0.10 to 0.15. In the aerosol-generating article according to the invention, the outer diameter of the cylindrical core portion may be at least 1 mm. Preferably, the outer diameter of the core portion is at least about 3 mm. More preferably, the outer diameter of the core portion is at least about 3.5 mm. The outer diameter of the core portion is preferably less than 8 mm. More preferably, the outer diameter of the core portion is less than 7 mm. Even more preferably, the outer diameter of the core portion is less than 5.75 mm.

In some embodiments, the outer diameter of the core portion is 3 mm to 8 mm, preferably 3 mm to 7 mm, more preferably 3 mm to 5.75 mm. In another embodiment, the outer diameter of the core portion is between 3.5 mm and 8 mm, preferably between 3.5 mm and 7 mm, and even more preferably between 3.5 mm and 5.75 mm.

Preferably, the density of the aerosol-generating substrate is at least about 150 mg/cm³. More preferably, the density of the aerosol-generating substrate is at least about 175 mg/cm³. More preferably, the density of the aerosol-generating substrate is at least about 200 mg/cm³. Even more preferably, the density of the aerosol-generating substrate is at least about 250 mg/cm³. Even more preferably, the density of the aerosol-generating substrate is at least about 300, 400, 500 mg/cm³. Preferably, the density of the aerosol-generating substrate is about 1500 mg/cm³ or less. More preferably, the density of the aerosol-generating substrate is about 1000 mg/cm³ or less. More preferably, the density of the aerosol-generating substrate is about 800 mg/cm³ or less. Even more preferably, the density of the aerosol-generating substrate is less than or equal to about 700 mg/cm³.

For example, the density of the aerosol-generating substrate is preferably from about 150 mg/cm³ to about 1500 mg/cm³, preferably from about 175 mg/cm³ to about 450 mg/cm³, more preferably from about 200 mg/cm³ to about 400 mg/cm³, Even more preferably, it is about 250 mg/cm³ to about 350 mg/cm³. In a particularly preferred embodiment of the invention, the density of the aerosol-generating substrate is about 300 mg/cm³.

In certain preferred embodiments, the aerosol-generating substrate within the core portion has a density of from about 150 mg/cm³ to about 500 mg/cm³, preferably from about 175 mg/cm³ to about 450 mg/cm³, more preferably from about 200 mg/cm³ to about 200 mg/cm³. shredded tobacco material, such as tobacco cut filler, having a density of 400 mg/cm³, more preferably about 250 mg/cm³ to about 350 mg/cm³, most preferably about 300 mg/cm³.

The aerosol-generating substrate may be a solid aerosol-generating substrate. The aerosol-generating substrate preferably contains an aerosol former. The aerosol former may be any suitable known compound or mixture of compounds that facilitates the formation of a dense and stable aerosol when used. Aerosol formers can facilitate the aerosol to be substantially resistant to thermal degradation at temperatures typically applied during use of the aerosol-generating article. For example, suitable aerosol formers include polyhydric alcohols such as triethylene glycol, 1,3-butanediol, propylene glycol and glycerin; Esters of polyhydric alcohols, for example glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as, for example, dimethyl dodecanedioate and dimethyl tetradecanedioate; and combinations thereof.

Preferably, the aerosol former contains one or more of glycerin and propylene glycol. The aerosol former may consist of glycerin or propylene glycol or a combination of glycerin and propylene glycol.

Preferably, the aerosol-generating substrate contains at least 5% by weight of an aerosol former based on the dry weight of the aerosol-generating substrate, more preferably 10% to 22% by weight of an aerosol former based on the dry weight of the cut aerosol-generating substrate. comprising an aerosol former, more preferably the amount of the aerosol former is 12% to 19% by weight based on the dry weight of the aerosol-generating substrate, for example, most of the aerosol-forming agent is included in the drying of the aerosol-generating substrate. It is 13% to 16% by weight.

In certain preferred embodiments of the invention, the aerosol-generating substrate comprises shredded tobacco material. For example, the shredded tobacco material may be in the form of cut filler, as described in more detail below. Alternatively, the shredded tobacco material may be in the form of shredded sheets of homogenized tobacco material. Suitable homogenized tobacco materials for use in the present invention are described below.

In the context of this specification, the term "cut filler" is used to describe a blend of shredded plant material, such as tobacco plant material, in particular comprising one or more of the blades, processed stems and ribs of the homogenized plant material. .

Cut fillers may also include other cuts, cut filler tobacco or casings.

Preferably, the cut sheath comprises at least 25% of the plant foliage, more preferably at least 50% of the plant foliage, even more preferably at least 75% of the plant foliage, and most preferably at least 90% of the plant foliage there is. Preferably, the plant material is one of tobacco, mint, tea and clove. Most preferably, the plant material is tobacco. However, as will be discussed in more detail below, the invention is equally applicable to other plant materials that have the ability to release substances upon application of heat which can subsequently form an aerosol.

Preferably, the cut tobacco comprises one or more lamina of bright tobacco, dark tobacco, flavored tobacco and cut tobacco. With reference to the present invention, the term “tobacco” describes any plant member of the genus Nicotiana.

Bright tobacco is generally a tobacco with large, light-colored leaves. Throughout this specification, the term “bright tobacco” is used to refer to heat-dried tobacco. Examples of bright tobacco are Chinese xanthoma, Brazilian xanthoma, American xanthoma such as Virginia tobacco, Indian xanthoma, Tanzanian xanthoma or other African xanthoma. Bright tobacco is characterized by a high sugar to nitrogen ratio. From a sensory standpoint, bright tobacco is a type of tobacco that is associated with a spicy and lively sensation after drying. In the context of the present invention, bright tobacco is tobacco having a reducing sugar content of about 2.5% to about 20% by dry weight of leaves and a total ammonia content of less than about 0.12% by dry weight of leaves. Reducing sugars include, for example, glucose or fructose. Total ammonia includes, for example, ammonia and ammonia salts.

Dark tobacco is generally tobacco with large, dark-colored leaves. Throughout this specification, the term “dark tobacco” is used to refer to air-dried tobacco. Additionally, dark tobacco can be fermented. Chewing tobacco, snuff, cigars and tobacco used primarily in pipe blends also fall into this category. Typically, these dark tobaccos are air dried and possibly fermented. From a sensory standpoint, dark tobacco is a type of tobacco that smells like smoke after curing and is associated with a dark cigar type sensation. Dark tobacco is characterized by a low sugar to nitrogen ratio. Examples of dark tobacco are Burley Malawi or other African Burley, fumigated Brazilian Gaufang, sun-dried or air-dried Indonesian Kasturi. According to the present invention, dark tobacco is tobacco having a reducing sugar content of less than about 5% based on the dry weight of the leaves and a total ammonia content of up to about 0.5% based on the dry weight of the leaves.

Flavored tobacco is usually a tobacco with small, light-colored leaves. Throughout this specification, the term “flavored tobacco” is used for other tobaccos with a high aromatic content, for example of essential oils. From a sensory standpoint, flavored tobacco is a type of tobacco that, after curing, is associated with spicy and aromatic sensations. Examples of flavored tobaccos are Greek Oriental, Oriental Turkey, and Semi-Oriental tobacco, as well as perique, rustica, American Burley or fired American Burley, such as Maryland. Cut tobacco is not a specific tobacco type, but is primarily used to complement other tobacco types used in a blend and includes tobacco types that do not induce a specific characteristic aroma aroma in the final product. An example of a cut tobacco is the stem or stem of another type of tobacco. A specific example might be heat-dried sacks of Brazilian xanthoma lower stems.

Cut fillers suitable for use with the present invention may be similar to cut fillers used in conventional smoking articles. The cutting width of the cut sheath is preferably 0.3 mm to 2.0 mm, more preferably, the cutting width of the cut sheath is 0.5 mm to 1.2 mm, and most preferably, the cutting width of the cut sheath is 0.6 mm to 0.9 mm. The width of the cut can play a role in the heat distribution inside the rod of the aerosol-generating substrate. Additionally, the width of the cut may play a role in the pull resistance of the core portion. Additionally, the cut width can have an overall effect on the overall density and cross-sectional porosity of the core portion.

The strand length of the cut sheath is a somewhat random value, as the length of the strand will depend on the overall size of the object from which the strand is cut. Nevertheless, by conditioning the material prior to cutting, for example by controlling the moisture content and overall compactness of the material, longer strands can be cut. Preferably, the strands have a length of about 10 mm to about 40 mm before the strands are gathered to form a rod of aerosol-generating substrate. Obviously, if the strands are arranged within a rod of the aerosol-generating substrate in the longitudinal extension of the section being less than 40 mm, the final core portion of the aerosol-generating substrate may comprise strands that are on average shorter than the initial strand length. Preferably, the strand length of the cut sheath is such that about 20% to 60% of the strands extend along the entire length of the rod of aerosol-generating substrate. This prevents the strands from easily leaving the rod of the aerosol-generating substrate.

In a preferred embodiment, the weight of the cut filler is 80 mg to 400 mg, preferably 150 mg to 250 mg, more preferably 170 mg to 220 mg. This amount of cut filler typically allows sufficient material for the formation of an aerosol. Additionally, taking into account the constraints on diameter and size described above, it is important to note that the aerosol-generating substrate has a balance between energy absorption, suction resistance and fluid passages within the rod of the aerosol-generating substrate comprising plant material, and the core portion comprising the aerosol-generating substrate. Allows for a certain density.

Preferably, the cut paste is impregnated with an aerosol former. Impregnating the cut paste can be accomplished by spraying or by other suitable application methods. Aerosol formers can be applied to the blend during the manufacture of the cut filler. For example, the aerosol former can be applied to the blend in a direct conditioning casing cylinder (DCCC). Conventional machinery can be used to apply the aerosol former to the cut filler. The aerosol former may be any suitable known compound or mixture of compounds that facilitates the formation of a dense and stable aerosol when used. Aerosol formers can facilitate the aerosol to be substantially resistant to thermal degradation at temperatures typically applied during use of the aerosol-generating article. Suitable aerosol formers include, for example, polyhydric alcohols such as triethylene glycol, 1,3-butanediol, propylene glycol, and glycerin; Esters of polyhydric alcohols such as glycerol mono-, di- or triacetate; Aliphatic esters of mono-, di- or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate; and combinations thereof.

Preferably, the aerosol former contains one or more of glycerin and propylene glycol. The aerosol former may consist of glycerin or propylene glycol or a combination of glycerin and propylene glycol.

Preferably, the amount of aerosol former is at least 5% by weight based on the dry weight of the cut filler, preferably 10% to 22% by weight based on the dry weight of the cut filler, more preferably, the amount of aerosol former is 10% by weight of the cut filler. 12% to 19% by dry weight, for example, the amount of aerosol former is 13% to 16% by weight based on the dry weight of the cut filler. When aerosol formers are added to cut fillers in the amounts described above, the cut fillers may become relatively sticky. This advantageously helps maintain the cut filler in a predetermined position within the article, as the particles of the cut filler display a tendency to adhere to surrounding cut filler particles as well as to surrounding surfaces (e.g., the inner surface of the wrapper surrounding the cut filler). Helping.

For some embodiments, the amount of aerosol former has a target value of about 13% by weight based on the dry weight of the cut filler. The most efficient amount of aerosol former will also depend on the cut filler, whether the cut filler contains plant lamina or homogenized plant material. For example, the type of cut sheath, among other factors, will determine the extent to which an aerosol former can facilitate the release of substances from the cut sheath.

For this reason, the core portion containing the cut sheath as described above can efficiently generate a sufficient amount of aerosol at a relatively low temperature. A temperature of 150°C to 200°C in the heating chamber may be sufficient for one such cut filler to generate a sufficient amount of aerosol, while temperatures of about 250°C are typically used in aerosol-generating devices using tobacco cast rib sheets.

An additional advantage associated with operating at lower temperatures is the reduced need to cool the aerosol. Since lower temperatures are typically used, simpler cooling functions may be sufficient. This, in turn, makes it possible to use simpler and less complex structures of aerosol-generating articles.

In another preferred embodiment, the aerosol-generating substrate comprises homogenized plant material, preferably homogenized tobacco material.

As used herein, the term “homogenized plant material” encompasses any plant material formed by agglomeration of particles of a plant. For example, a sheet or web of homogenized tobacco material for the aerosol-generating substrate of the present invention may be formed by agglomerating particles of tobacco material obtained by micronizing, milling or grinding plant material and, optionally, one or more of tobacco leaf blades and tobacco petioles. You can. Homogenized plant material may be produced by casting, extrusion, papermaking processes, or any other suitable process known in the art.

Homogenized plant material may be provided in any suitable form.

In some embodiments, the homogenized plant material may be in the form of one or more sheets. As used herein in connection with the present invention, the term “sheet” describes a laminated element having a width and length substantially greater than its thickness.

The homogenized plant material may be in the form of a plurality of pellets or granules.

Homogenized plant material may be in the form of a plurality of strands, strips, or shreds. As used herein, the term “strand” describes an elongated element of material having a length substantially greater than its width and thickness. The term “strand” should be considered to include strips, pieces and any other homogenized plant material having a similar shape. Strands of homogenized plant material may be formed into sheets of homogenized plant material, for example by cutting or crushing, or for example by other methods, for example extrusion methods.

In some embodiments, strands may be formed in situ within the aerosol-generating substrate, for example as a result of crimping, splitting or cracking of the sheet of homogenized plant material during formation of the aerosol-generating substrate. . The strands of homogenized plant material within the aerosol-generating substrate may be separate from one another. Alternatively, each strand of homogenized plant material within the aerosol-generating substrate may be at least partially connected to an adjacent strand or strands along the length of the strands. For example, adjacent strands may be connected by one or more fibers. This can occur, for example, if strands are formed due to the splitting of sheets of homogenized plant material during the production of the aerosol-generating substrate, as described above.

If the homogenized plant material is in the form of one or more sheets, the sheets may be manufactured by a casting process, as described above. Alternatively, sheets of homogenized plant material can be manufactured by a papermaking process.

One or more sheets described herein may each individually have a thickness of 100 μm to 600 μm, preferably 150 μm to 300 μm, and most preferably 200 μm to 250 μm. Individual thickness refers to the thickness of individual sheets, while combined thickness refers to the total thickness of all sheets that make up the aerosol-generating substrate. For example, if the aerosol-generating substrate is formed from two separate sheets, the combined thickness is the sum of the measured thicknesses of the two individual sheets or the two sheets with the two sheets laminated to the aerosol-generating substrate.

One or more sheets as described herein can each individually have a basis weight of about 100 gsm to about 600 gsm.

One or more sheets as described herein each individually weigh about 0.3 g/cm³. It may have a density of from about 1.3 g/cm³, preferably from about 0.7 g/cm³ to about 1.0 g/cm³.

In embodiments of the invention where the aerosol-generating substrate comprises one or more sheets of homogenized plant material, the sheets are preferably in the form of one or more corrugated sheets. As used herein, the term “gathered” refers to a sheet of homogenized plant material being rolled, folded, or otherwise compressed or contracted substantially transversely to the cylindrical axis of the plug or rod.

One or more sheets of homogenized plant material may be gathered transversely about its longitudinal axis and surrounded by a wrapper to form a continuous rod or plug.

One or more sheets of homogenized plant material may advantageously be crimped or similarly processed. As used herein, the term “crimped” refers to a sheet having a plurality of substantially parallel ridges or corrugations. One or more sheets of homogenized plant material may be embossed, engraved, perforated, or otherwise modified to provide texture on one or both sides of the sheet.

Preferably, each sheet of homogenized plant material may be crimped to have a plurality of ridges or corrugations substantially parallel to the cylindrical axis of the plug. This treatment advantageously facilitates the corrugation of the crimped sheet of homogenized plant material to form a plug. Preferably, one or more sheets of homogenized plant material may be corrugated. It will be appreciated that the crimped sheet of homogenized plant material may alternatively or additionally have a plurality of substantially parallel ridges and corrugations disposed at an acute or obtuse angle to the cylindrical axis of the plug. The sheet may be crimped to a degree that the integrity of the sheet is destroyed in the plurality of parallel ridges or corrugations causing separation of the material, resulting in the formation of pieces, strands or strips of homogenized plant material.

Alternatively, one or more sheets of homogenized plant material can be cut into strands as mentioned above. In this embodiment, the aerosol-generating substrate comprises a plurality of strands of homogenized plant material. Strands can be used to form the core portion as a plug. Typically, the width of these strands is no more than about 5 mm, or about 4 mm, or about 3 mm, or about 2 mm. The length of the strand may be greater than about 5 mm, from about 5 mm to about 15 mm, from about 8 mm to about 12 mm, or about 12 mm. Preferably, the strands have substantially the same length as each other.

Homogenized plant material may comprise up to about 95% plant particles by weight on a dry weight basis. Preferably, the homogenized plant material contains, on a dry weight basis, at most about 90% plant particles, more preferably at most about 80% plant particles, more preferably at most about 70% plant particles by weight, even more preferably Preferably it comprises up to about 60% by weight plant particles, more preferably at most about 50% by weight plant particles.

For example, the homogenized plant material may comprise, on a dry weight basis, from about 2.5% to about 95% plant particles, or from about 5% to about 90% plant particles, or from about 10% to about 80% plant particles, by weight. , or from about 15% to about 70% by weight of plant particles, or from about 20% to about 60% by weight of plant particles, or from about 30% to about 50% by weight of plant particles.

In certain embodiments of the invention, the homogenized plant material is a homogenized tobacco material comprising tobacco particles. Sheets of homogenized tobacco material for use in this embodiment of the invention may have at least about 40% by dry weight, more preferably at least about 50% by dry weight, more preferably at least about It may have a tobacco content of 70% by weight, most preferably at least about 90% by weight on a dry weight basis.

With reference to the present invention, the term “tobacco particles” describes particles of any plant member of the genus Nicotiana . The term “tobacco particles” includes ground or powdered tobacco blades, ground or powdered tobacco petioles, tobacco dust, tobacco fines, and other particulate tobacco by-products formed during the processing, handling and shipping of tobacco. In a preferred embodiment, the tobacco particles are derived substantially entirely from tobacco leaves. In contrast, isolated nicotine and nicotine salts are derived from tobacco, but are not considered tobacco particles for the purposes of this invention and are not included in the percentage of particulate plant material.

The homogenized plant material may further include one or more aerosol formers. Upon evaporation, the aerosol former can deliver in the aerosol other vaporized compounds that are released from the aerosol-generating substrate upon heating, such as nicotine and flavoring agents. Suitable aerosol formers for inclusion in the homogenized plant material are known in the art and include, but are not limited to, polyhydric alcohols such as triethylene glycol, propylene glycol, 1,3-butanediol and glycerol; Esters of polyhydric alcohols such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate.

The homogenized plant material forms an aerosol of about 5% to about 30% by dry weight, such as about 10% to about 25% by dry weight, or about 15% to about 20% by dry weight. It can have its own content. Aerosol formers can act as wetting agents in the homogenized plant material.

The core portion may include a core wrapper surrounding the aerosol-forming substrate. Accordingly, the core wrapper is sandwiched between the aerosol-generating substrate and the annular portion, and the outer surface of the core wrapper effectively defines the outer surface of the core portion. In certain embodiments, the annular portion radially abuts the core portion and the outer surface of the core wrapper abuts the inner surface of the annular portion, such that the core wrapper effectively defines an interface between the core portion and the annular portion.

As a result, the aerosol-generating rod may comprise a rod wrapper that entirely surrounds the annular portion. Accordingly, the outer surface of the rod wrapper defines the outer surface of the aerosol-generating rod.

The core wrapper surrounding the aerosol-generating substrate may be a paper wrapper or a non-paper wrapper. Equally, the rod wrapper surrounding the annular portion may be a paper wrapper or a non-paper wrapper.

The core wrapper may have an air permeability of less than 1000 CORESTA units. In certain preferred embodiments, the core wrapper has an air permeability of less than 100 CORESTA units. More preferably, the core wrapper has an air permeability of less than 80 CORESTA units. Even more preferably, the core wrapper has an air permeability of less than 60 CORESTA units.

The core wrapper may have an air permeability of at least 5 CORESTA units. Preferably, the core wrapper has an air permeability of at least 10 CORESTA units. More preferably, the core wrapper has an air permeability of at least 20 CORESTA units.

In certain embodiments, the core wrapper has an air permeability of from 5 CORESTA units to 100 CORESTA units, preferably from 5 CORESTA units to 80 CORESTA units, more preferably from 5 CORESTA units to 60 CORESTA units. In another embodiment, the core wrapper has an air permeability of 10 CORESTA units to 100 CORESTA units, preferably 10 CORESTA units to 80 CORESTA units, more preferably 10 CORESTA units to 60 CORESTA units. In a further embodiment, the core wrapper has an air permeability of 20 CORESTA units to 100 CORESTA units, preferably 20 CORESTA units to 80 CORESTA units, more preferably 20 CORESTA units to 60 CORESTA units.

Providing a core wrapper with air permeability within the preferred ranges described above can impede and substantially prevent radial airflow across the core wrapper, such that airflow from the core portion into the annular portion and vice versa is substantially impeded.

This can advantageously improve the technical advantages associated with the present invention and described above, when the aerosol-generating article is not paired with an aerosol-generating device or when the aerosol-generating article is paired with the wrong aerosol-generating device. , the low permeability core wrapper will substantially prevent lateral airflow from the annular portion into the core portion, and thus substantially all of the air drawn into the annular portion will flow longitudinally through the annular portion from one end to the other. am. Therefore, the low permeability core wrapper exerts a synergistic effect with substantial differences in the cross-sectional porosity and relative arrangement of the core portion and the annular portion.

Suitable paper wrappers for use in certain embodiments of the invention are known in the art and include cigarette paper; and filter plug wraps. Suitable non-paper wrappers for use in certain embodiments of the invention are known in the art. Including, but not limited to, sheets of homogenized tobacco material. Below, the characteristics of suitable paper and non-paper wrappers will be discussed in more detail. The paper and non-paper wrappers described below can be used as core wrappers or as load wrappers or both.

The paper wrapper may have a basis weight of at least 15 gsm, preferably at least 20 gsm. The paper wrapper may have a basis weight of 35 gsm or less, preferably 30 gsm or less. The paper wrapper may have a basis weight of 15 gsm to 35 gsm, preferably 20 gsm to 30 gsm. In a preferred embodiment, the paper wrapper may have a basis weight of 25 gsm. The paper wrapper may have a thickness of at least 25 μm, preferably at least 30 μm and more preferably 35 μm. The paper wrapper may have a thickness of 55 μm or less, preferably 50 μm or less, and more preferably 45 μm or less. The paper wrapper may have a thickness of 25 ㎛ to 55 ㎛, preferably 30 ㎛ to 50 ㎛, more preferably 35 ㎛ to 45 ㎛. In a preferred embodiment, the paper wrapper may have a thickness of 40 μm.

In certain preferred embodiments, the wrapper may be formed from a layered material comprising multiple layers. Preferably, the wrapper is formed from aluminum co-laminated sheets. The use of co-laminated sheets comprising aluminum advantageously prevents combustion of the aerosol-generating substrate in cases where the aerosol-generating substrate is to be ignited rather than heated in the intended manner.

The paper layers of the co-laminated sheets may have a basis weight of at least 35 gsm, preferably at least 40 gsm. The paper layers of the co-laminated sheets may have a basis weight of 55 gsm or less, preferably 50 gsm or less. The paper layers of the co-laminated sheets may have a basis weight of 35 gsm to 55 gsm, preferably 40 gsm to 50 gsm. In a preferred embodiment, the paper layers of the co-laminated sheets may have a basis weight of 45 gsm.

The paper layer of the co-laminated sheet may have a thickness of at least 50 μm, preferably at least 55 μm, more preferably at least 60 μm. The paper layer of the co-laminated sheet may have a thickness of 80 μm or less, preferably 75 μm or less, more preferably 70 μm or less.

The paper layer of the co-laminated sheets may have a thickness of 50 μm to 80 μm, preferably 55 μm to 75 μm, more preferably 60 μm to 70 μm. In a preferred embodiment, the paper layer of the co-laminated sheets may have a thickness of 65 μm.

The metal layers of the co-laminated sheets may have a basis weight of at least 12 gsm, preferably at least 15 gsm. The metal layers of the co-laminated sheets may have a basis weight of 25 gsm or less, preferably 20 gsm or less. The metal layers of the co-laminated sheets may have a basis weight of 12 gsm to 25 gsm, preferably 15 gsm to 20 gsm. In a preferred embodiment, the metal layers of the co-laminated sheets may have a basis weight of 17 gsm.

The metal layer of the co-laminated sheet may have a thickness of at least 2 μm, preferably at least 3 μm and more preferably at least 5 μm. The metal layer of the co-laminated sheet may have a thickness of 15 μm or less, preferably 12 μm or less, more preferably 10 μm or less.

The metal layer of the co-laminated sheet may have a thickness of 2 μm to 15 μm, preferably 3 μm to 12 μm, more preferably 5 μm to 10 μm. In a preferred embodiment, the metal layer of the co-laminated sheet may have a thickness of 6 μm.

The wrapper, especially the road wrapper, may be a paper wrapper containing PVOH (polyvinyl alcohol) or silicone. The addition of PVOH (polyvinyl alcohol) or silicone can improve the grease barrier properties of the wrapper.

PVOH or silicone may be applied to the paper layer as a surface coating, such as disposed on the outer surface of the paper layer of a wrapper surrounding the aerosol-generating rod. PVOH or silicone can be placed on the outer surface of the paper layer of the wrapper to form a layer. PVOH or silicone can be placed on the inner surface of the paper layer of the wrapper. PVOH or silicone can be disposed on the interior surface of the paper layer of the aerosol-generating article to form the layer. PVOH or silicone can be disposed on the inner and outer surfaces of the paper layer of the wrapper. PVOH or silicone can be disposed on the inner and outer surfaces of the paper layer of the wrapper to form a layer.

The paper wrapper comprising PVOH or silicone may have a basis weight of at least 20 gsm, preferably at least 25 gsm, more preferably at least 30 gsm. The paper wrapper comprising PVOH or silicone may have a basis weight of 50 gsm or less, preferably 45 gsm or less, more preferably 40 gsm or less. The paper wrapper comprising PVOH or silicone may have a basis weight of 20 gsm to 50 gsm, preferably 25 gsm to 45 gsm, more preferably 30 gsm to 40 gsm. In a particularly preferred embodiment, the paper wrapper comprising PVOH or silicone may have a basis weight of about 35 gsm.

The paper wrapper comprising PVOH or silicone may have a thickness of at least 25 μm, preferably at least 30 μm, more preferably at least 35 μm. The paper wrapper comprising PVOH or silicone may have a thickness of 50 μm or less, preferably 45 μm or less, more preferably 40 μm or less. The paper wrapper comprising PVOH or silicone may have a thickness of 25 μm to 50 μm, preferably 30 μm to 45 μm, more preferably 35 μm to 40 μm. In a particularly preferred embodiment, the paper wrapper comprising PVOH or silicone may have a thickness of 37 μm.

The wrapper, especially the core wrapper, may comprise a flame retardant composition comprising one or more flame retardant compounds. The term “flame retardant compound” is used herein to describe chemical compounds that, when added to or otherwise incorporated into a carrier substrate, such as a paper or plastic compound, provide varying degrees of flammability protection to the carrier substrate. In fact, flame retardant compounds can be activated by the presence of an ignition source and are adapted to prevent or slow down the further occurrence of ignition by a variety of different physical and chemical mechanisms.

Flame retardant compositions may typically further comprise one of a number of non-flame retardant compounds, i.e. one or more compounds - such as solvents, excipients, fillers - which do not actively contribute to providing flammability protection to the carrier substrate. The flame retardant compound or compounds are used to facilitate application onto or into the wrapper or both. Some of the non-flame retardant compounds of the flame retardant composition - such as solvents - are volatile and may evaporate from the wrapper upon drying after the flame retardant composition is applied onto or into the wrapping base material or both. As such, although these non-flame retardant compounds form part of the formulation of the flame retardant composition, they may no longer be present or may only be detectable in trace amounts within the wrapper of the aerosol-generating article.

Many suitable flame retardant compounds are known to those skilled in the art. In particular, several flame retardant compounds and formulations suitable for processing cellulosic materials are known, disclosed, and can be used in the preparation of wrappers for aerosol-generating articles according to the invention.

For example, the flame retardant composition may comprise at least one mono-, di- and/or tri-carboxylic acid, at least one polyphosphoric acid, a polymer based on pyrophosphoric acid and/or phosphoric acid and mixed salts, and hydroxides of alkali or alkaline earth metals. or a salt, wherein the at least one mono, di- and/or tri-carboxylic acid and the hydroxide or salt form a carboxylate and the at least one polyphosphoric acid, pyrophosphoric acid and/or phosphoric acid and the hydroxide or salt forms a phosphate. Preferably, the flame retardant composition may further include carbonate salts of alkali or alkaline earth metals. Alternatively, the flame retardant composition may include cellulose modified with at least one C ₁₀ or higher fatty acid, high oil fatty acids (TOFA), phosphorylated flaxseed oil, phosphorylated subsequent corn oil. Preferably, the at least one C ₁₀ or higher fatty acid is selected from the group consisting of capric acid, myristic acid, palmitic acid, and combinations thereof.

In wrappers comprising a flame retardant composition suitable for use in aerosol-generating articles according to the present invention, the flame retardant composition may be provided within the treated portion of the wrapper. This means that the flame retardant composition has been applied onto or into the corresponding part of the wrapping base material of the wrapper or both. Accordingly, in the treated portion, the wrapper has an overall dry basis weight that is greater than the dry basis weight of the wrapping base material. The treated portion of the wrapper spans at least about 10% of the outer surface area of the core portion surrounded by the wrapper, more preferably over at least about 20% of the outer surface area of the core portion surrounded by the wrapper. may extend over at least about 40% of the outer surface area of the core portion, even more preferably over at least about 60% of the outer surface area of the core portion. Most preferably, the treated portion of the wrapper extends over at least about 80% of the outer surface area of the core portion. In particularly preferred embodiments, the treated portion of the wrapper extends over at least about 90% or even 95% of the outer surface area of the core portion. Most preferably, the treated portion of the wrapper extends substantially over the entire outer surface area of the core portion.

The wrapper comprising the flame retardant composition may have a basis weight of at least 20 gsm, preferably at least 25 gsm, more preferably at least 30 gsm. The wrapper comprising the flame retardant composition may have a basis weight of 45 gsm or less, preferably 40 gsm or less, more preferably 35 gsm or less. The wrapper comprising the flame retardant composition may have a basis weight of 20 gsm to 45 gsm, preferably 25 gsm to 40 gsm, more preferably 30 gsm to 35 gsm. In some preferred embodiments, the wrapper comprising the flame retardant composition may have a basis weight of 33 gsm.

The wrapper comprising the flame retardant composition may have a thickness of at least 25 μm, preferably at least 30 μm, and even more preferably 35 μm. The wrapper comprising the flame retardant composition may have a thickness of 50 μm or less, preferably 45 μm or less, and even more preferably 40 μm or less. In some embodiments, the wrapper comprising the flame retardant composition can have a thickness of 37 μm.

In some embodiments, the aerosol-generating article may include a susceptor element arranged within the core portion and thermally coupled to the aerosol-generating substrate. As used herein, the term “susceptor element” refers to an element comprising a material capable of converting electromagnetic energy into heat. When the susceptor element is placed in an alternating electromagnetic field, the susceptor is heated. Heating of the susceptor element may be the result of at least one of hysteresis losses or eddy currents induced in the susceptor, depending on the electrical and magnetic properties of the susceptor material.

In the aerosol-generating article according to the invention, the annular portion advantageously separates the susceptor element provided within the core portion from the periphery of the aerosol-generating article - for example from the core wrapper. This is advantageous in that accidental self-ignition of the aerosol-generating article can be prevented due to direct cooperation between the paper-containing core wrapper and the misaligned susceptor elements. Additionally, during or immediately after use, the annular portion may act as an insulating barrier between the hot surface of the susceptor element and the consumer.

The provision of a susceptor element within the core part also has the advantage that the heat source is inside the core part. On the other hand, external heating - i.e. supplying heat through heating elements arranged on the outside of the aerosol-generating article - will be less efficient because the annular portion may act as an insulating barrier.

The susceptor element may be arranged such that when the aerosol-generating article is received within the cavity of the aerosol-generating device, the oscillating electromagnetic field generated by the inductor coil induces an electric current within the susceptor element, thereby heating the susceptor element. In these embodiments, the aerosol-generating device has a magnetic field strength (H- It can generate a fluctuating electromagnetic field with magnetic field intensity). The electrically operated aerosol generating device is preferably capable of generating a fluctuating electromagnetic field with a frequency between 1 and 30 MHz, for example between 1 and 10 MHz, for example between 5 and 7 MHz.

The susceptor element may include any suitable material. The susceptor element may be formed of any material that can be inductively heated to a temperature sufficient to release volatile compounds from the aerosol-forming substrate. Suitable materials for elongated susceptor elements include graphite, molybdenum, silicon carbide, stainless steel, niobium, aluminum, nickel, nickel-containing compounds, titanium, and composites of metallic materials. Some susceptor elements contain metal or carbon. Advantageously, the susceptor element may comprise or consist of ferromagnetic materials, such as ferritic iron, ferromagnetic alloys such as ferromagnetic steel or stainless steel, ferromagnetic particles, and ferrite. Suitable susceptor elements may be or include aluminum. The susceptor element preferably contains more than 5%, preferably more than 20%, more preferably more than 50% or more than 90% of ferromagnetic or paramagnetic material. Some elongated susceptor elements can be heated to temperatures exceeding about 250°C.

The susceptor element may include a non-metallic core with a metal layer disposed on the non-metallic core. For example, the susceptor element may include a ceramic core or a metal track formed on the outer surface of the substrate.

In some embodiments, the aerosol-generating device can include at least one resistive heating element and at least one inductive heating element. In some embodiments, the aerosol-generating device may include a combination of resistive and inductive heating elements.

During use, the heater may be controlled to operate in a defined operating temperature range below the maximum operating temperature. An operating temperature range of about 150° C. to about 300° C. within the heating chamber (or device cavity) is preferred. The operating temperature range of the heater may be about 150°C to about 250°C.

Preferably, the operating temperature range of the heater may be from about 150°C to about 200°C. More preferably, the operating temperature range of the heater may be about 180°C to about 200°C. In particular, as mentioned in this disclosure, when using an aerosol-generating device with an external heater having an operating temperature range of about 180° C. to about 200° C. (e.g., having a downstream section RTD of less than 15 mmH ₂ O) It has been found that optimal and consistent aerosol delivery can be achieved with aerosol-generating articles having relatively low RTDs.

The susceptor elements may be in the form of elongated susceptors arranged longitudinally within the aerosol-generating substrate. When used to describe a susceptor element, the term "elongate" means that the susceptor element has a length dimension that is greater than its width dimension or its thickness dimension, for example, greater than twice its width dimension or its thickness dimension. It means having.

The susceptors may be arranged substantially longitudinally within the core portion. This means that the length dimension of the elongated susceptor is arranged approximately parallel to the longitudinal direction of the aerosol-generating rod, for example within ±10 degrees parallel to the longitudinal direction of the aerosol-generating rod. In a preferred embodiment, the elongated susceptor can be positioned at a radially central position within the aerosol-generating rod and extends along the longitudinal axis of the aerosol-generating rod.

In a particularly preferred embodiment, the susceptor has substantially the same length as the aerosol-generating rod and extends from the upstream end of the core portion to the downstream end of the core portion. The susceptor is preferably in the form of a pin, rod, strip or blade.

If the susceptor has the form of a strip or blade, the strip or blade preferably has a rectangular shape with a width of 2 mm to 6 mm, more preferably 2.5 mm to 5.5 mm, even more preferably 3 mm to 5 mm. As an example, a susceptor in the form of a strip of blade may have a width of approximately 3.75 mm.

In a preferred embodiment, the elongated susceptor is in the form of a strip or blade, has a substantially rectangular shape, and has a thickness of about 55 μm to about 65 μm.

In the aerosol-generating article according to the invention, the aerosol-generating rod further comprises an air-permeable annular portion surrounding the core portion and extending coaxially with the core portion. The annular portion extends radially from an inner periphery of the annular portion to an outer periphery of the annular portion. The distance between the inner periphery of the annular portion and the outer periphery of the annular portion, measured along the radial direction, can be described as the thickness of the annular portion.

Preferably, the rod of aerosol-generating substrate has a substantially uniform cross-section along the length of the rod. Particularly preferably, the cross-section of the annular portion is an area comprised between two concentric circles defined by the transverse plane and the intersection of the outer and inner peripheries of the annular portion, wherein the radii of the two concentric circles are equal to that of the aerosol-generating load. It remains substantially constant along its length. As such, the thickness of the annular portion is preferably substantially constant along the length of the aerosol-generating rod.

Preferably, the annular portion and the core portion have the same length.

The cross-sectional porosity of the annular portion is at least 120% of the cross-sectional porosity of the core portion. Preferably, the cross-sectional porosity of the annular portion is at least 130% of the cross-sectional porosity of the core portion. More preferably, the cross-sectional porosity of the annular portion is at least 140% of the cross-sectional porosity of the core portion. Even more preferably, the cross-sectional porosity of the annular portion is at least 150% of the cross-sectional porosity of the core portion.

In some embodiments, the cross-sectional porosity of the annular portion may be at least 175% of the cross-sectional porosity of the core portion, and preferably at least 200% of the cross-sectional porosity of the core portion.

In certain embodiments, the cross-sectional porosity of the annular portion is at least 200% of the cross-sectional porosity of the core portion, preferably at least 250% of the cross-sectional porosity of the core portion, more preferably at least 300% of the cross-sectional porosity of the core portion. , more preferably 400% of the cross-sectional porosity of the core portion, or 500% of the cross-sectional porosity of the core portion, or 600% of the cross-sectional porosity of the core portion.

In some embodiments, the cross-sectional porosity of the annular portion is 120% to 600% of the cross-sectional porosity of the core portion, or 120% to 500% of the cross-sectional porosity of the core portion, or 120% to 400% of the cross-sectional porosity of the core portion. It may be 120% to 300% of the cross-sectional porosity or 120% to 200% of the cross-sectional porosity of the core portion.

In other embodiments, the cross-sectional porosity of the annular portion is 130% to 600% of the cross-sectional porosity of the core portion, or 130% to 500% of the cross-sectional porosity of the core portion, or 130% to 400% of the cross-sectional porosity of the core portion. It may be 130% to 300% of the cross-sectional porosity or 130% to 200% of the cross-sectional porosity of the core portion.

In a further embodiment, the cross-sectional porosity of the annular portion is 140% to 600% of the cross-sectional porosity of the core portion, or 140% to 500% of the cross-sectional porosity of the core portion, or 140% to 400% of the cross-sectional porosity of the core portion. It may be 140% to 300% of the cross-sectional porosity or 140% to 200% of the cross-sectional porosity of the core portion.

In another embodiment, the cross-sectional porosity of the annular portion is 150% to 600% of the cross-sectional porosity of the core portion, or 150% to 500% of the cross-sectional porosity of the core portion, or 150% to 400% of the cross-sectional porosity of the core portion, or It may be 150% to 300% of the cross-sectional porosity of or 150% to 200% of the cross-sectional porosity of the core portion.

The cross-sectional porosity of the annular portion may be up to 0.99.

Preferably, the cross-sectional porosity of the annular portion is less than 0.95. More preferably, the cross-sectional porosity of the annular portion is less than 0.90. Even more preferably, the cross-sectional porosity of the annular portion is less than 0.85. This is advantageous in that it can ensure a certain structural strength of the annular part and the rod as a whole.

The cross-sectional porosity of the annular portion may be at least 0.3. Preferably, the cross-sectional porosity of the annular portion is at least 0.35. More preferably, the cross-sectional porosity of the annular portion is at least 0.4. Even more preferably, the cross-sectional porosity of the annular portion is at least 0.45.

In some embodiments, the cross-sectional porosity of the annular portion is 0.3 to 0.95, preferably 0.35 to 0.95, more preferably 0.4 to 0.95, and even more preferably 0.5 to 0.95. In another embodiment, the cross-sectional porosity of the annular portion is 0.3 to 0.90, preferably 0.35 to 0.90, more preferably 0.4 to 0.90, even more preferably 0.5 to 0.90. In a further embodiment, the cross-sectional porosity of the annular portion is 0.3 to 0.85, preferably 0.35 to 0.85, more preferably 0.4 to 0.85, even more preferably 0.5 to 0.85.

Due to these low porosity values, the annular portion exhibits a significantly lower resistance to draw (RTD) than the RTD of the core portion.

In the aerosol-generating article according to the invention, the RTD of the annular portion is preferably less than 65 mmH ₂ O. More preferably, the RTD of the annular portion is preferably less than 60 mmH ₂ O. Even more preferably, the RTD of the annular portion is preferably less than 55 mmH ₂ O.

The RTD of the annular portion may be at least 5 mmH ₂ O. Preferably, the RTD of the annular portion is at least 10 mmH ₂ O. More preferably, the RTD of the annular portion is at least 20 mmH ₂ O. Even more preferably, the RTD of the annular portion is at least 30 mmH ₂ O.

In some embodiments, the RTD of the annular portion is between 10 mmH ₂ O and 65 mmH ₂ O, preferably between 10 mmH ₂ O and 60 mmH ₂ O, more preferably between 10 mmH ₂ O and 55 mmH ₂ O. In another embodiment, the RTD of the annular portion is between 20 mmH ₂ O and 65 mmH ₂ O, preferably between 20 mmH ₂ O and 60 mmH ₂ O, more preferably between 20 mmH ₂ O and 55 mmH ₂ O. In a further embodiment, the RTD of the annular portion is between 30 mmH ₂ O and 65 mmH ₂ O, preferably between 30 mmH ₂ O and 60 mmH ₂ O, more preferably between 30 mmH ₂ O and 55 mmH ₂ O.

The annular portion may comprise, for example, a porous material such as foam or a fibrous material such as a non-woven material.

The annular portion may include fibrous material. In some embodiments, the annular portion comprises a plurality of fibers, preferably linear and axially oriented fibers. As used herein, the expression “linear and axially oriented fibers” is used to describe a plurality of fibers that are substantially aligned with one another along the axis of the annular portion, or along the direction of aerosol intake. This is in contrast to fibers that are oriented multidirectionally or randomly or both multidirectionally and randomly, i.e. a plurality of different or random orientations and different and random orientations, including both parallel and perpendicular to the axial or direction of aerosol intake. In contrast to a plurality of fibers that are mainly misaligned.

Suitable fibers will be known to those skilled in the art. Preferably, the annular portion is made of: cellulose acetate fibers, polylactic acid (PLA) fibers, polypropylene fibers, poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHVB) fibers, rayon fibers, viscose fibers, recycled fibers. It contains fibers selected from cellulose fibers, and combinations thereof.

In certain embodiments, the annular portion may comprise two or more longitudinal segments of tow material, wherein the tow material of adjacent ones of the two or more longitudinal segments are joined together at least along the longitudinal edges of the segments to form a unitary annulus. form part. At least two or all of the parts may be formed from the same tow.

Preferably, the annular portion comprises fibers having a denier per filament (dpf) of at least 3.0. More preferably, the annular portion comprises fibers having a dpf of at least 5.0. More preferably, the annular portion comprises fibers having a dpf of at least 6.0.

Preferably, the annular portion comprises fibers having a dpf of less than or equal to 15.0. More preferably, the annular portion comprises fibers having a dpf of 10.0 or less. Even more preferably, the annular portion comprises fibers having a dpf of less than or equal to 9.0.

In some embodiments, the annular portion comprises fibers having a dpf of 3.0 to 15.0, preferably 3.0 to 10.0, more preferably 3.0 to 9.0. In another embodiment, the annular portion comprises fibers having a dpf of 5.0 to 15.0, preferably 5.0 to 10.0, more preferably 5.0 to 9.0. In a further embodiment, the annular portion comprises fibers having a dpf of 6.0 to 15.0, preferably 6.0 to 10.0, more preferably 6.0 to 9.0.

In some embodiments, the fibers can have a Y-shaped cross-section.

The outer diameter of the annular portion may be up to 10 mm. Preferably, the outer diameter of the annular portion is less than 9 mm. More preferably, the outer diameter of the annular portion is less than 7.7 mm.

In the aerosol-generating article according to the invention, the thickness of the annular portion may be at least 0.5 mm. Preferably, the thickness of the annular portion is at least 1.0 mm. More preferably, the thickness of the annular portion is at least 1.5 mm. The thickness of the annular portion may be less than 5.0 mm. Preferably, the thickness of the annular portion is less than 4.0 mm. More preferably, the thickness of the annular portion is less than 3.5 mm. Even more preferably, the thickness of the annular portion is less than 3.0 mm.

In some embodiments, the thickness of the annular portion is 0.5 mm to 4 mm, preferably 0.5 mm to 3.5 mm, more preferably 0.5 mm to 3 mm. In another embodiment, the thickness of the annular portion is 1.0 mm to 4 mm, preferably 1.0 mm to 3.5 mm, more preferably 1.0 mm to 3 mm. In a further embodiment, the thickness of the annular portion is between 1.5 mm and 4 mm, preferably between 1.5 mm and 3.5 mm, more preferably between 1.5 mm and 3 mm.

In a preferred embodiment, the annular portion borders the core portion radially. That is, the annular portion immediately surrounds the core portion. In these embodiments, the inner periphery of the annular portion is immediately adjacent to the outer periphery of the cylindrical core portion, for example as defined by the outer surface of the core wrapper, and thus the annular portion extends from the outer periphery of the cylindrical core portion. It extends radially to the outer periphery of. Accordingly, the inner diameter of the annular portion substantially matches the outer diameter of the core portion.

As briefly described above, the aerosol-generating article according to the invention comprises a downstream section provided downstream of the aerosol-generating rod and abutting the downstream end of the aerosol-generating rod.

The downstream section can have any length. The downstream section may have a length of at least 10 mm. For example, the downstream section can have a length of at least 15 mm, at least 20 mm, at least 25 mm, or at least 30 mm.

Providing a downstream section with a length greater than the values stated above can advantageously provide space for the aerosol to cool and condense before reaching the consumer. This can also ensure that the user is away from the heating element when the aerosol-generating article is used with an aerosol-generating device.

The downstream section may have a length of less than 80 mm. For example, the downstream section may have a length of less than 70 mm, less than 60 mm, less than 50 mm, or less than 40 mm.

The ratio between the length of the downstream section and the length of the aerosol-generating rod may be from 1.0 to about 4.5. Preferably, the ratio between the length of the downstream section and the length of the aerosol-generating rod is at least 1.25, more preferably at least 1.5, and even more preferably at least 2.0. In a preferred embodiment, the ratio between the length of the downstream section and the length of the aerosol-generating rod is less than or equal to 4.0, preferably less than 3.5 and even more preferably less than 3.0.

The length of the downstream section corresponds substantially to the sum of the lengths of the individual components forming the downstream section.

In a preferred embodiment, the downstream section comprises hollow tubular elements. The hollow tubular element defines an internal cavity, and the upstream end of the hollow tubular element abuts the downstream end of the aerosol-generating rod. In this embodiment, the inner diameter of the annular portion is preferably smaller than the inner diameter of the hollow tubular element, such that the annular portion is in direct fluid communication with the internal cavity of the hollow tubular element.

In the aerosol-generating article according to the invention, the length of the hollow tubular element may be at least 5 mm. Preferably, the length of the hollow tubular element is at least 10 mm. More preferably, the length of the hollow tubular element is at least 12 mm. Even more preferably, the length of the hollow tubular element is at least 15 mm.

Preferably, the length of the hollow tubular element is not more than 45 mm. More preferably, the length of the hollow tubular element is 40 mm or less. Even more preferably, the length of the hollow tubular element is 40 mm or less.

In a preferred embodiment, the hollow tubular element has a length of 35 mm or less. More preferably, the length of the hollow tubular element is 30 mm or less. Even more preferably, the hollow tubular element has a length of 25 mm or less. In a particularly preferred embodiment, the hollow tubular element has a length of 22 mm or less.

In some embodiments, the length of the hollow tubular element is 10 mm to 45 mm, preferably 10 mm to 40 mm, more preferably 10 mm to 35 mm, even more preferably 10 mm to 30 mm. In a particularly preferred embodiment, the length of the hollow tubular element is between 10 mm and 25 mm, preferably between 10 mm and 22 mm.

In another embodiment, the length of the hollow tubular element is 12 mm to 45 mm, preferably 12 mm to 40 mm, more preferably 12 mm to 35 mm, even more preferably 12 mm to 30 mm. In a particularly preferred embodiment, the length of the hollow tubular element is between 12 mm and 25 mm, preferably between 12 mm and 22 mm.

In a further embodiment, the length of the hollow tubular element is 15 mm to 45 mm, preferably 15 mm to 40 mm, more preferably 15 mm to 35 mm, even more preferably 15 mm to 30 mm. In a particularly preferred embodiment, the length of the hollow tubular element is between 15 mm and 25 mm, preferably between 15 mm and 22 mm.

The hollow tubular element may have an internal diameter of at least 3.5 mm. For example, the hollow tubular element may have an internal diameter of at least 4 mm, at least 5 mm, or at least 6 mm.

By providing a hollow tubular element with an inner diameter as described above, it is advantageously possible to provide the hollow tubular element with sufficient rigidity and strength.

The hollow tubular element may have an internal diameter of 7 mm or less. The hollow tubular element may have an internal diameter of 6.5 mm or less.

By providing a hollow tubular element with an inner diameter as described above, it is advantageously possible to reduce the resistance to suction of the hollow tubular element.

The hollow tubular element may have an internal diameter of 3.5 mm to 7 mm, 4 mm to 7 mm, 5 mm to 7 mm, or 6 mm to 7 mm. The hollow tubular element may have an internal diameter of 3.5 mm to 6.5 mm, 4 mm to 6.5 mm, 5 mm to 6.5 mm, or 6 mm to 6.5 mm.

The outer diameter of the hollow tubular element preferably substantially matches the outer diameter of the annular portion. It may also be approximately equal to the outer diameter of the aerosol-generating article.

The ratio between the inner diameter of the hollow tubular element and the outer diameter of the hollow tubular element may be at least about 0.8. For example, the ratio between the inner diameter of the hollow tubular element and the outer diameter of the hollow tubular element can be at least about 0.85, at least about 0.9, or at least about 0.95.

The ratio between the inner diameter of the hollow tubular element and the outer diameter of the hollow tubular element may be about 0.99 or less. For example, the ratio between the inner diameter of the hollow tubular element and the outer diameter of the hollow tubular element may be about 0.98 or less.

The ratio between the inner diameter of the hollow tubular element and the outer diameter of the hollow tubular element may be about 0.97.

Providing a relatively large inner diameter can advantageously reduce the suction resistance of the hollow tubular element.

The lumen of the hollow tubular element can have any cross-sectional shape. The lumen of the hollow tubular element may have a circular cross-sectional shape.

The hollow tubular element can be formed from any material. For example, the hollow tubular element can include cellulose acetate tow. When the hollow tubular element comprises cellulose acetate tow, the hollow tubular element may have a thickness of about 0.1 mm to about 1 mm. The hollow tubular element may have a thickness of approximately 0.5 mm.

When the hollow tubular element includes cellulose acetate tow, the cellulose acetate tow may have a dpf of about 2 to about 4 and a total denier of about 25 to about 40.

The hollow tubular element may contain paper. The hollow tubular element may include at least one paper layer. The paper can be a very stiff paper. The paper may be crimped paper, such as crimped heat resistant paper or crimped parchment. Paper can be cardboard. The hollow tubular element may be a paper tube. The hollow tubular element may be a tube formed from spirally wound paper. The hollow tubular element can be formed from multiple layers of paper. The paper may have a basis weight of at least about 50 gsm, at least about 60 gsm, at least about 70 gsm, or at least about 90 gsm.

If the tubular element includes paper, the paper may have a thickness of at least about 50 μm. For example, the paper can have a thickness of at least about 70 μm, at least about 90 μm, or at least about 100 μm.

The hollow tubular element may comprise a polymer. For example, the hollow tubular element can include a polymer film. The polymeric film may include a cellulose film. The hollow tubular element may include low density polyethylene (LDPE) or polyhydroxyalkanoate (PHA) fibers.

Preferably, in embodiments where the downstream section comprises a hollow tubular element, the inner diameter of the annular portion is smaller than the inner diameter of the hollow tubular element. In this way, direct fluid communication is established between the annular portion and the internal cavity defined by the hollow tubular element.

Accordingly, when the aerosol-generating article is not contained within an aerosol-generating device or is contained within an aerosol-generating device not designed for use with an aerosol-generating article, air drawn into the aerosol-generating rod from the upstream end is primarily directed through the annular portion and into the hollow tubular element. will flow directly into the cavity of As such, the RTD encountered by this airflow following the aerosol-generating article will depend only on any components of the downstream section other than the hollow tubular elements, if any such component is present. For example, the overall RTD encountered by this flow of air following the aerosol-generating article may depend solely on the RTD of the mouthpiece, as will be discussed in more detail below.

In some embodiments, an aerosol-generating article according to the invention comprises a ventilation zone at a location along the hollow tubular element. The ventilation zone may allow cooler air from outside the aerosol-generating article to enter the interior cavity of the hollow tubular element.

Aerosol-generating articles can typically have a ventilation level of at least about 10%, preferably at least about 20%.

In preferred embodiments, the aerosol-generating article has a ventilation level of at least about 20% or 25% or 30%. More preferably, the aerosol-generating article has a ventilation level of at least about 35%.

Aerosol-generating articles preferably have a ventilation level of less than about 80%. More preferably, the aerosol-generating article has a ventilation level of less than about 60% or less than about 50%.

Aerosol-generating articles can typically have ventilation levels of about 10% to about 80%.

In some embodiments, the aerosol-generating article has a ventilation level of about 20% to about 80%, preferably about 20% to about 60%, more preferably about 20% to about 50%. In other embodiments, the aerosol-generating article has a ventilation level of about 25% to about 80%, preferably about 25% to about 60%, more preferably about 25% to about 50%. In further embodiments, the aerosol-generating article has a ventilation level of about 30% to about 80%, preferably about 30% to about 60%, more preferably about 30% to about 50%.

In particularly preferred embodiments, the aerosol-generating article has a ventilation level of about 40% to about 50%. In some particularly preferred embodiments, the aerosol-generating article has a ventilation level of about 45%.

Without being bound by theory, the inventors have discovered that the temperature drop caused by introducing cooler outside air into the hollow tubular segment can have a beneficial effect on the nucleation and growth of aerosol particles.

The formation of aerosols from gas mixtures containing various chemical species depends on delicate interactions between nucleation, evaporation, and condensation as well as coalescence, all accounting for changes in vapor concentration, temperature, and velocity fields. The so-called classical nucleation theory is based on the assumption that the fraction of gas phase molecules is large enough to remain coherent for long periods of time with sufficient probability (e.g., half probability). These molecules represent some class of critical critical molecular clusters among transient molecular assemblies, meaning that, on average, smaller molecular clusters are likely to disintegrate into the gas phase rather quickly, whereas larger clusters are, on average, more likely to grow. it means. These main clusters are identified as the main nucleation cores from which droplets are expected to grow due to condensation of molecules from the vapor. It is assumed that a freshly nucleated pure droplet appears at a certain original diameter and can then grow by several orders of magnitude. This can be facilitated and enhanced by rapid cooling of the surrounding vapor leading to condensation. In this regard, it is helpful to remember that evaporation and condensation are two aspects of one and the same mechanism, gas-liquid mass transfer. While evaporation involves a net mass transfer from the liquid droplet to the vapor phase, condensation is a net mass transfer from the vapor phase to the droplet phase. Evaporation (or condensation) will cause the droplets to shrink (or grow), but the number of droplets will not change.

In these scenarios, which can be further complicated by coalescence phenomena, cooling temperature and rate can play an important role in determining how the system responds. In general, since the nucleation process is typically non-linear, different cooling rates can result in significantly different temporal behavior with respect to the formation of the liquid phase (droplet). Without being bound by theory, it is assumed that cooling may cause a rapid increase in the number concentration of the droplets, which may be followed by a strong and short-lived increase in growth (nucleation burst). This nucleation burst would appear to be more significant at lower temperatures. It would also appear that higher cooling rates may favor an earlier onset of nucleation. In contrast, reducing the cooling rate would appear to have a positive effect on the final size that the aerosol droplets ultimately reach.

Therefore, rapid cooling induced by introducing external air into the hollow tubular segment can be advantageously used to favor the nucleation and growth of aerosol droplets. However, at the same time, the introduction of external air into the hollow tubular segment has the immediate disadvantage of diluting the aerosol stream delivered to the consumer.

The inventors have surprisingly found that the dilution effect on aerosols - which can be assessed in particular by measuring the effect on the delivery of aerosol formers (such as glycerol) contained in the aerosol-generating substrate - is advantageous when ventilation levels are within the above-mentioned range. was found to be minimized. In particular, ventilation levels of 25% to 50%, and even more preferably 28 to 42%, have been found to result in particularly satisfactory values of glycerin delivery. At the same time, the degree of nucleation and, consequently, the delivery of nicotine and aerosol formers (eg glycerol) are improved.

The thickness of the peripheral wall of the hollow tubular element (i.e., wall thickness) may be at least about 100 μm. The wall thickness of the hollow tubular element may be at least about 150 μm. Preferably, the wall thickness of the hollow tubular element is at least about 200 μm, preferably at least about 250 μm, and more preferably at least about 500 μm (or 0.5 mm).

The wall thickness of the hollow tubular element may be less than or equal to 2 mm, preferably less than or equal to 1.5 mm, and even more preferably less than or equal to 1.25 mm. The wall thickness of the hollow tubular element may be less than 1 mm. The wall thickness of the hollow tubular element may be less than 500 μm.

The wall thickness of the hollow tubular element may be between 100 μm and 2 mm, preferably between 150 μm and 1.5 mm and even more preferably between 200 μm and 1.25 mm.

The wall thickness of the hollow tubular element may preferably be about 250 μm (0.25 mm).

Keeping the thickness of the peripheral wall of the hollow tubular element relatively low ensures that the overall internal volume of the hollow tubular element and the hollow surface are available for aerosols to initiate the nucleation process as soon as the aerosol component exits the rod of the aerosol-generating substrate. ensuring that the cross-sectional surface area of the tubular element is effectively maximized, while at the same time the hollow tubular element has the necessary structural strength to prevent collapse of the aerosol-generating article as well as to provide some support to the aerosol-generating rod, and Ensures that the RTD of the tubular elements is minimized. It is understood that a larger value of the cross-sectional surface area of the cavity of the hollow tubular element is associated with a reduced velocity of the aerosol stream moving along the aerosol-generating article, which is also expected to favor aerosol nucleation. Additionally, by using hollow tubular elements with a relatively small thickness, it would appear possible to substantially prevent the diffusion of the ventilation air before contacting and mixing with the stream of aerosols, which is also understood to be more favorable to the nucleation phenomenon. Indeed, by providing more controllably localized cooling of the stream of volatilized species, it is possible to enhance the effect of cooling on the formation of new aerosol particles.

The ventilation zone may include a first line of perforated holes surrounding a hollow tubular element. In some implementations, the ventilation zone may comprise, for example, two circumferential rows of perforated holes. For example, perforated holes may be formed en masse during manufacture of the aerosol-generating article. Each circumferential row of perforations may include from about 5 to about 40 perforations, for example, each circumferential row of perforations may include from about 8 to about 30 perforations.

When the aerosol-generating article comprises a bonding plug wrap, the ventilation zone preferably comprises at least one row of perforated holes on its circumference provided through a portion of the bonding plug wrap. They may also be formed en masse during the manufacture of the smoking article. Preferably, the circumferential row(s) of perforations provided through a portion of the engagement plug wrap are substantially aligned with the row(s) of perforations through the downstream section.

If the aerosol-generating article comprises a band of tipping paper, the band of tipping paper extends across the circumferential row(s) of perforations in the downstream section, and the ventilation zone preferably includes at least one of the perforated holes provided through the band of tipping paper. Contains one corresponding circumferential row. They may also be formed en masse during the manufacture of the smoking article. Preferably, the circumferential row(s) of perforations provided through the band of tipping paper are substantially aligned with the row(s) of perforations through the downstream section.

The ventilation zone may be located anywhere along the length of the hollow tubular element.

In some embodiments, the ventilation zone can be located at least 8 mm from the downstream end of the aerosol-generating article. For example, the downstream end of the ventilation zone can be located at least 10 mm, at least 12 mm, or at least 15 mm from the downstream end of the aerosol-generating article. Positioning the first ventilation zone as described above can advantageously prevent the first ventilation zone from being occluded by the consumer's mouth or lips when the aerosol-generating article is in use.

The ventilation zone may be located no more than 25 mm from the downstream end of the aerosol-generating article. For example, the ventilation zone may be located 20 mm from the downstream end of the aerosol-generating article. Positioning the ventilation zone as described above can advantageously prevent the ventilation zone from being occluded when an aerosol-generating article is inserted into the aerosol-generating device.

The ventilation zone may be located at least 2 mm from the upstream end of the hollow tubular element. For example, the ventilation zone may be located at least 3 mm from the upstream end of the hollow tubular element, or at least 4 mm from the upstream end of the hollow tubular element, or at least 5 mm from the upstream end of the hollow tubular element.

In some embodiments, the ventilation zone is less than 20 mm from the downstream end of the hollow tubular element, preferably less than 18 mm from the downstream end of the hollow tubular element, more preferably less than 16 mm from the downstream end of the hollow tubular element, and even more preferably It may be positioned less than 14 mm from the downstream end of the hollow tubular element.

In the context of the invention, hollow tubular elements provide unrestricted flow channels. This means that the hollow tubular element provides negligible resistance to draw (RTD). The term "negligible RTD" means less than 1 mmH ₂ O per 10 mm of the hollow tubular element or length of the hollow tubular element, preferably less than 0.4 mmH ₂ O per 10 mm of the length of the hollow tubular element or hollow tubular element, more preferably is used to describe a hollow tubular element or an RTD of less than 0.1 mmH ₂ O per 10 mm of the length of a hollow tubular element.

Unless otherwise specified, the resistance of attraction (RTD) of a component or aerosol-generating article is measured according to ISO 6565-2015. RTD refers to the pressure required to force air through the entire length of a component. The terms “pressure drop” or “pull resistance” of a component or article may also refer to “resistance to suction.” These terms generally refer to the output of the component at a rate of about 17.5 beats per second at the output or downstream end, normally measured at a temperature of about 22° C., a pressure of about 101 kPa (about 760 torr), and a relative humidity of about 60%, according to ISO 6565-2015. Refers to measurements performed under testing at volumetric flow rates in milliliters.

The RTD of the hollow tubular element is preferably about 10 mmH ₂ O or less. More preferably, the RTD of the hollow tubular element is about 5 mmH ₂ O or less. Even more preferably, the length RTD of the hollow tubular element is less than or equal to about 2.5 mmH ₂ O. Even more preferably, the RTD of the hollow tubular element is about 2 mmH ₂ O or less. Even more preferably, the RTD of the hollow tubular element is about 1 mmH ₂ O or less.

The RTD of the hollow tubular element may be at least 0 mmH ₂ O, or at least about 0.25 mmH ₂ O, or at least about 0.5 mmH ₂ O, or at least about 1 mmH ₂ O.

In some embodiments, the RTD of the hollow tubular element is from about 0 mmH ₂ O to about 10 mmH ₂ O, preferably from about 0.25 mmH ₂ O to about 10 mmH ₂ O, preferably from about 0.5 mmH ₂ O to about 10 mmH ₂ O. In another embodiment, the RTD of the hollow tubular element is from about 0 mmH ₂ O to about 5 mmH ₂ O, preferably from about 0.25 mmH ₂ O to about 5 mmH ₂ O, preferably from about 0.5 mmH ₂ O to about 5 mmH ₂ O. In other embodiments, the RTD of the hollow tubular element is from about 1 mmH ₂ O to about 5 mmH ₂ O. In a further embodiment, the RTD of the hollow tubular element is from about 0 mmH ₂ O to about 2.5 mmH ₂ O, preferably from about 0.25 mmH ₂ O to about 2.5 mmH ₂ O, more preferably from about 0.5 mmH ₂ O to about 2.5 mmH. ₂ O. In a further embodiment, the RTD of the hollow tubular element is from about 0 mmH ₂ O to about 2 mmH ₂ O, preferably from about 0.25 mmH ₂ O to about 2 mmH ₂ O, more preferably from about 0.5 mmH ₂ O to about 2 mmH ₂ O. . In a particularly preferred embodiment, the RTD of the hollow tubular element is about 0 mmH ₂ O.

In an aerosol-generating article according to the invention, the overall RTD of the article essentially depends on the RTD of the aerosol-generating rod and, optionally, also depends on the RTD of other components of the downstream section, for example the mouthpiece, as described below. can do. This is because the hollow tubular portion is substantially empty and, as such, contributes substantially only a minor amount to the overall RTD of the aerosol-generating article. Accordingly, the internal cavity of the hollow tubular element must be free of any components that would impede the flow of air in the longitudinal direction. Preferably, the internal cavity is substantially empty.

In practice, since the annular portion does not contribute substantially to the overall RTD of the article, the overall RTD of the article depends primarily on the core portion and, optionally, on components of the downstream sections other than the hollow tubular elements.

In an aerosol-generating article according to the invention, the downstream section may comprise a mouthpiece element. In some embodiments, the downstream section includes a mouthpiece element downstream of the hollow tubular element, and the article further includes an aerosol-generating rod, a hollow tubular element, and a wrapper surrounding the mouthpiece.

The mouthpiece element may be positioned immediately downstream of the hollow tubular element. Accordingly, the mouthpiece element may extend from the downstream end of the hollow tubular element to the mouth end of the aerosol-generating article or to the downstream end of the downstream section.

In this embodiment, as the hollow tubular element abuts the upstream end of the mouthpiece element, the internal cavity of the hollow tubular element is in direct fluid communication with the mouthpiece element.

In an aerosol-generating article according to the invention, the length of the mouthpiece element may be at least 5 mm. Preferably, the length of the mouthpiece element is at least 10 mm. More preferably, the length of the mouthpiece element is at least 12 mm. Even more preferably, the length of the mouthpiece element is at least 15 mm.

Preferably, the length of the mouthpiece element is no more than 45 mm. More preferably, the length of the mouthpiece element is 40 mm or less. Even more preferably, the length of the mouthpiece element is 40 mm or less.

In a preferred embodiment, the length of the mouthpiece element is 35 mm or less. More preferably, the length of the mouthpiece element is 30 mm or less. Even more preferably, the length of the mouthpiece element is 25 mm or less. In a particularly preferred embodiment, the length of the mouthpiece element is 22 mm or less.

In some embodiments, the length of the mouthpiece element is 10 mm to 45 mm, preferably 10 mm to 40 mm, more preferably 10 mm to 35 mm, even more preferably 10 mm to 30 mm. In a particularly preferred embodiment, the length of the mouthpiece element is between 10 mm and 25 mm, preferably between 10 mm and 22 mm.

In another embodiment, the length of the mouthpiece element is 12 mm to 45 mm, preferably 12 mm to 40 mm, more preferably 12 mm to 35 mm, even more preferably 12 mm to 30 mm. In a particularly preferred embodiment, the length of the mouthpiece element is between 12 mm and 25 mm, preferably between 12 mm and 22 mm.

In a further embodiment, the length of the mouthpiece element is 15 mm to 45 mm, preferably 15 mm to 40 mm, more preferably 15 mm to 35 mm, even more preferably 15 mm to 30 mm. In a particularly preferred embodiment, the length of the mouthpiece element is between 15 mm and 25 mm, preferably between 15 mm and 22 mm.

The outer diameter of the mouthpiece element preferably substantially matches the outer diameter of the annular portion or the outer diameter of the hollow tubular element, or both.

The mouthpiece element may be formed from a fibrous material.

The mouthpiece element may be formed from a porous material. The mouthpiece element may be formed from a biodegradable material. The mouthpiece element may be formed from a cellulosic material, such as cellulose acetate. The mouthpiece element may be formed from a polylactic acid-based material. The mouthpiece element may be formed from a bioplastic material, preferably a starch-based bioplastic material. Mouthpiece elements can be manufactured by injection molding or extrusion. Bioplastic-based materials are advantageous because they can provide simple to manufacture and inexpensive mouthpiece element structures with specific and complex cross-sectional profiles, which provide a plurality of mouthpiece element structures extending through the mouthpiece element material that provide appropriate RTD properties. It may contain a relatively large airflow channel.

The mouthpiece element may be formed from a sheet of suitable material that is crimped, bent, corrugated, woven or folded into elements defining a plurality of longitudinally extending channels. Sheets of such suitable materials may be formed from paper, cardboard, polymers such as polylactic acid, or any other cellulosic, paper-based or bioplastic-based material. The cross-sectional profile of these mouthpiece elements may exhibit randomly oriented channels.

The mouthpiece element may be formed in any other suitable manner. For example, the mouthpiece element may be formed as a bundle of longitudinally extending tubes. The longitudinally extending tube may be formed from polylactic acid. Mouthpiece elements can be formed by extrusion, molding, lamination, pouring, or crushing of suitable materials. Therefore, it is desirable for there to be a low, but non-zero, pressure drop (or RTD) from the upstream end of the mouthpiece element to the downstream end of the mouthpiece element.

The mouthpiece element may include at least one filter (airflow) channel extending along the mouthpiece element. Preferably, at least one filter airflow channel extends along the entire length of the mouthpiece element. At least one filter channel may have a substantially circular cross-section. At least one filter channel may have a substantially Y-shaped or T-shaped cross-section. The mouthpiece element may include a plurality of such filter airflow channels extending along the mouthpiece element. The mouthpiece element may include at least three filter airflow channels. Providing at least one filter airflow channel within the mouthpiece element allows the mouthpiece element to meet specific RTD values.

The resistance to draw (RTD) of the mouthpiece element may be at least about 0 mmH ₂ O. The RTD of the mouthpiece element may be at least about 3 mmH ₂ O. The RTD of the mouthpiece element may be at least about 6 mmH ₂ O.

The RTD of the mouthpiece element may be about 12 mmH ₂ O or less. The RTD of the mouthpiece element may be about 11 mmH ₂ O or less. The RTD of the mouthpiece element may be about 10 mmH ₂ O or less.

The resistance of suction of the mouthpiece element may be greater than about 0 mmH ₂ O and less than about 12 mmH ₂ O. Preferably, the resistance of suction of the mouthpiece element may be greater than about 3 mmH ₂ O and less than about 12 mmH ₂ O. The resistance of suction of the mouthpiece element may be greater than about 0 mmH ₂ O and less than about 11 mmH ₂ O. Even more preferably, the resistance of draw of the mouthpiece element may be greater than about 3 mmH ₂ O and less than about 11 mmH ₂ O. Even more preferably, the resistance of draw of the mouthpiece element may be greater than about 6 mmH ₂ O and less than about 10 mmH ₂ O. Preferably, the resistance to draw of the mouthpiece element may be about 8 mmH ₂ O.

The aerosol-generating article can have an overall length of about 30 mm to about 110 mm.

Preferably, the overall length of the aerosol-generating article according to the present invention is at least about 30 mm. More preferably, the overall length of the aerosol-generating article according to the present invention is at least about 40 mm. Even more preferably, the overall length of the aerosol-generating article according to the present invention is at least about 42 mm.

The overall length of the aerosol-generating article according to the invention is preferably 90 mm or less. More preferably, the overall length of the aerosol-generating article according to the invention is preferably 80 mm or less. Even more preferably, the overall length of the aerosol-generating article according to the invention is preferably 70 mm or less.

In some embodiments, the overall length of the aerosol-generating article is preferably between 30 mm and 90 mm, more preferably between 40 mm and 90 mm, and even more preferably between 42 mm and 90 mm. In another embodiment, the overall length of the aerosol-generating article is preferably between 30 mm and 80 mm, more preferably between 40 mm and 80 mm, and even more preferably between 42 mm and 80 mm. In a further embodiment, the overall length of the aerosol-generating article is preferably between 30 mm and 70 mm, more preferably between 40 mm and 70 mm, and even more preferably between 42 mm and 70 mm.

The outer diameter of the aerosol-generating article may be at least 4 mm. Preferably, the outer diameter of the aerosol-generating article is at least 5 mm. More preferably, the outer diameter of the aerosol-generating article is at least 6 mm. The outer diameter of the aerosol-generating article is preferably 12 mm or less, more preferably 10 mm or less, and even more preferably 8 mm or less.

In some embodiments, the outer diameter of the aerosol-generating article is between 4 mm and 12 mm, preferably between 4 mm and 10 mm, and more preferably between 4 mm and 8 mm. In another embodiment, the outer diameter of the aerosol-generating article is 5 mm to 12 mm, preferably 5 mm to 10 mm, more preferably 5 mm to 8 mm. In a further embodiment, the outer diameter of the aerosol-generating article is between 6 mm and 12 mm, preferably between 6 mm and 10 mm, more preferably between 6 mm and 8 mm.

The outer diameter of the aerosol-generating article may be substantially constant over the entire length of the aerosol-generating article. Alternatively, different parts of the aerosol-generating article may have different outer diameters.

In a particularly preferred embodiment, one or more components of the aerosol-generating article are individually surrounded by their own wrappers.

In one embodiment, the aerosol-generating rod and mouthpiece elements are individually packaged. The aerosol-generating rod and hollow tubular element are then combined with the outer wrapper. The combined aerosol-generating rod and hollow tubular element are then further combined with the mouthpiece element - which has its own wrapper - by means of tipping paper.

Preferably, at least one of the components of the aerosol-generating article is wrapped with a hydrophobic wrapper.

The term “hydrophobic” describes a surface that exhibits water-repellent properties. One useful way to determine hydrophobicity is to measure the water contact angle. “Water contact angle” is the angle at which the liquid/vapor interface meets the solid surface, typically measured through liquids. The water contact angle quantifies the wettability of a solid surface by a liquid using Young's equation. Hydrophobic or water contact angle is measured using the TAPPI T558 test, and the result is expressed as the interfacial contact angle, reported in "degrees" and can range from approximately 0 degrees to 180 degrees. .

In a preferred embodiment, the hydrophobic wrapper comprises a paper layer having a water contact angle of at least about 30 degrees, preferably at least about 35 degrees, or at least about 40 degrees, or at least about 45 degrees.

By way of example, the paper layer may include PVOH (polyvinyl alcohol) or silicone. PVOH may be applied to the paper layer as a surface coating, or the paper layer may include a surface treatment comprising PVOH or silicone.

In a particularly preferred embodiment, the aerosol-generating article according to the invention comprises, in a linear sequential arrangement, an aerosol-generating rod, a hollow tubular element positioned immediately downstream of the aerosol-generating rod, a mouthpiece element positioned immediately downstream of the hollow tubular element, and It includes one or more external wrappers combining an aerosol-generating rod, a hollow tubular element, and a mouthpiece element. The hollow tubular element and mouthpiece element form the downstream section of the aerosol-generating article.

The hollow tubular element may abut an aerosol-generating rod. The mouthpiece element may border the hollow tubular element. Preferably, the hollow tubular element abuts the aerosol-generating rod and the mouthpiece element abuts the hollow tubular element.

In this particularly preferred embodiment, the aerosol-generating article has a substantially cylindrical shape and an outer diameter of 4.9 mm to 9 mm. In a particularly preferred embodiment, the aerosol-generating article has a substantially cylindrical shape and an outer diameter of about 7.7 mm. The overall length of the aerosol-generating article is between 30 mm and 75 mm, and in a particularly preferred embodiment is 45 mm.

The aerosol-generating rod has a length of 5 mm to 25 mm. In a particularly preferred embodiment, the aerosol-generating rod has a length of about 11 mm. Preferably, the hollow tubular element has a length of about 5 mm to 35 mm. In a particularly preferred embodiment, the hollow tubular element has a length of about 11 mm. The mouthpiece element has a length of 5 mm to 15 mm. In a particularly preferred embodiment, the mouthpiece has a length of about 22 mm.

The overall length of the article is 15 mm to 75 mm. In a particularly preferred embodiment, the aerosol-generating article has a length of about 45 mm.

The aerosol-generating rod comprises a core portion containing at least one of the types of aerosol-generating substrates described above and preferably shredded tobacco material or corrugated homogenized tobacco material. In a preferred embodiment, the core portion comprises shredded tobacco material comprising 13% to 18% glycerol by weight.

The aerosol-generating rod includes an annular portion radially abutting the core portion and having an outer diameter substantially matching the outer diameter of the aerosol-generating article. In a particularly preferred embodiment, the thickness of the annular part is 1.8 mm. The inner diameter of the annular portion substantially matches the outer diameter of the core portion. The annular portion is formed from a plurality of linear, axially extending fibers of at least one of the types described above.

The hollow tubular elements are in the form of cardboard tubes or cellulose acetate tubes and have an inner diameter of 3.4 mm to 9.5 mm. The thickness of the peripheral wall of the hollow tubular segment is about 0.5 mm to 1.8 mm.

A ventilation zone comprising a circumferential row of openings is provided along the hollow tubular element 5 mm to 30 mm from the upstream end of the hollow tubular element.

The mouthpiece element is in the form of a low-density cellulose acetate filter segment.

As mentioned above, the present disclosure also relates to an aerosol-generating system comprising an aerosol-generating device having a distal end and a mouth end. The aerosol-generating device may include a body. The body or housing of the aerosol-generating device may define a device cavity for removably receiving an aerosol-generating article at the mouth end of the device. The aerosol-generating device may include a heating element and a heater for heating the aerosol-generating substrate when the aerosol-generating article is received within the device cavity.

The device cavity may be referred to as the heating chamber of the aerosol-generating device. The device cavity may extend between the distal end and the mouse, or the proximal end. The distal end of the device cavity may be a closed end and the mouse, or proximal end of the device cavity may be an open end. The aerosol-generating article can be inserted through the open end of the device cavity, into the device cavity, or into the heating chamber. The device cavity may be cylindrical in shape to conform to the same shape of the aerosol-generating article.

The expression “accommodated within” may refer to the fact that an element or element is fully or partially housed within another element or element. For example, the expression “an aerosol-generating article is received within a device cavity” refers to the aerosol-generating article being fully or partially contained within a device cavity of the aerosol-generating article. When an aerosol-generating article is received within a device cavity, the aerosol-generating article may abut a distal end of the device cavity. When the aerosol-generating article is received within the device cavity, the aerosol-generating article may be substantially proximate to the distal end of the device cavity. The distal end of the device cavity may be defined by the distal wall.

The length of the device cavity can be from about 10 mm to about 50 mm. The length of the device cavity can be from about 20 mm to about 40 mm. The length of the device cavity may be about 25 mm to about 30 mm.

The length of the device cavity (or heating chamber) may be equal to or greater than the length of the aerosol-generating rod. The length of the device cavity may be such that when an aerosol-generating article is received within the device cavity, the downstream section or portion thereof protrudes from the device cavity. The length of the device cavity may be such that when an aerosol-generating article is received within the device cavity, a portion of the downstream section (eg, a hollow tubular element or mouthpiece element) protrudes from the device cavity. The length of the device cavity may be configured such that when the aerosol-generating article is received within the device cavity, a portion of the downstream section (eg, a hollow tubular element or mouthpiece element) is received within the device cavity.

The diameter of the device cavity can be from about 4 mm to about 10 mm. The diameter of the device cavity may be about 5 mm to about 9 mm. The diameter of the device cavity may be about 6 mm to about 8 mm. The diameter of the device cavity may be about 7 mm to about 8 mm. The diameter of the device cavity may be about 7 mm to about 7.5 mm.

The diameter of the device cavity may be substantially equal to or larger than the diameter of the aerosol-generating article. The diameter of the device cavity may be the same as the diameter of the aerosol-generating article to establish an interference fit with the aerosol-generating article.

The device cavity may be configured to establish an interference fit with an aerosol-generating article contained within the device cavity. An interference fit can refer to a tight fit. The aerosol-generating device may include a perimeter wall. This peripheral wall may define a device cavity, or heating chamber. The peripheral wall defining the device cavity may be configured to engage with the aerosol-generating article contained within the device cavity in an interference fit manner, such that when received within the device cavity there is substantially a gap between the aerosol-generating article and the peripheral wall defining the device cavity. Or there is no empty space.

This interference fit can establish an airtight fit or configuration between the device cavity and the aerosol-generating article contained therein.

In this gas-tight configuration, there will be substantially no gap or void between the aerosol-generating article and the peripheral wall defining the device cavity for air to flow.

An interference fit with the aerosol-generating article may be established along the entire length of the device cavity or along a portion of the length of the device cavity.

The aerosol-generating device includes an airflow channel extending between a channel inlet and a channel outlet. The airflow channel may be configured to establish fluid communication between the interior of the device cavity and the exterior of the aerosol-generating device. An airflow channel of the aerosol-generating device may be defined within the housing of the aerosol-generating device to enable fluid communication between the interior of the device cavity and the exterior of the aerosol-generating device. When an aerosol-generating article is received within a device cavity, the airflow channel may be configured to provide airflow into the article to deliver the generated aerosol to a user who draws from the mouth end of the article.

More specifically, in the system according to the invention, the aerosol-generating device comprises a heating chamber at the proximal end for at least partially receiving an aerosol-generating rod for heating the aerosol-generating substrate, and the aerosol-generating device is positioned in a longitudinal direction of the heating chamber. It includes an opening at the distal end to allow airflow into the heating chamber along the axis. The diameter of this opening defining the airflow channel as described above is smaller than the inner diameter of the annular portion.

This has the advantage that when the aerosol-generating article is fully inserted into the heating chamber, direct fluid communication is established between the exterior of the aerosol-generating device and the core portion of the aerosol-generating rod. At the same time, the distal end wall surface on which the opening is formed effectively occludes the upstream end of the annular portion, such that fluid communication between the exterior of the aerosol-generating device and the annular portion is substantially inactivated, and airflow from the exterior of the aerosol-generating device into the annular portion is prevented. practically prevented.

As such, during use, the imbalance in porosity and RTD between the core portion and the annular portion will be offset and the overall RTD of the aerosol-generating article will substantially correspond to the sum of the RTD of the core portion and the RTD of the downstream sections.

During use, with the annular portion occluded, the RTD of the aerosol-generating system may be at least 60 mmH ₂ O, preferably at least 70 mmH ₂ O, more preferably at least 80 mmH ₂ O.

During use, with the annular portion occluded, the RTD of the aerosol-generating system may be less than or equal to 160 mmH ₂ O, preferably less than or equal to 150 mmH ₂ O, more preferably less than or equal to 140 mmH ₂ O.

In some embodiments, in the aerosol-generating device, the heater is an internal heater, such as a fin heater of a blade heater, configured to be inserted into the core portion when the aerosol-generating article is received within the heating chamber. The heater may be located within the device cavity or within the heating chamber.

The heater may include one or more resistive heating elements. Suitable materials for forming one or more resistive heating elements are: semiconductors such as doped ceramics, electrically 'conductive' ceramics (such as molybdenum disilicide, etc.), carbon, graphite, metals, metal alloys and ceramic materials and metals. Including, but not limited to, composite materials made from materials. These composite materials may include doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbide. Examples of suitable metals include titanium, zirconium, tantalum, and metals of the platinum group. Examples of suitable metal alloys include stainless steel, nickel-, cobalt-, chromium-, aluminum-, titanium-, zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese- , and iron-containing alloys, and superalloys based on nickel, iron, cobalt, stainless steel, Timetal®, and iron-manganese-aluminum based alloys.

In some implementations, the one or more resistive heating elements include one or more stampings of an electrically resistive material, such as stainless steel. Alternatively, the at least one resistive heating element may comprise a heating wire or filament, such as Ni-Cr (nickel-chromium), platinum, tungsten or alloy wire.

In some embodiments, the heater includes an electrically insulating substrate, where one or more resistive heating elements are provided on the electrically insulating substrate.

The electrically insulating substrate may include any suitable material. For example, the electrically insulating substrate can include one or more of paper, glass, ceramic, anodized metal, coated metal, and polyimide. Ceramics may include mica, alumina (Al ₂ O ₃ ), or zirconia (ZrO ₂ ). Preferably, the electrically insulating substrate has a thermal conductivity of about 40 W/mK or less, preferably about 20 W/mK or less, and ideally about 2 W/mK or less.

The heater may include a heating element comprising a rigid electrically insulating substrate having one or more electrically conductive tracks or wires disposed on its surface. The size and shape of the electrically insulating substrate allows the electrically insulating substrate to be inserted directly into the aerosol-generating substrate. If the electrically insulating substrate is not sufficiently rigid, the heating element may comprise additional reinforcement means. Electrical current may pass through one or more electrically conductive tracks to heat the heating element and the aerosol-generating substrate.

In another embodiment, as described above, the aerosol-generating article includes a susceptor element embedded within the core portion and adapted to heat the aerosol-generating substrate. In these embodiments, the heater within the aerosol-generating device may include an induction heating arrangement. The induction heating device may include an inductor coil and a power supply configured to provide a high-frequency oscillating current to the inductor coil. As used herein, high-frequency oscillating current refers to an oscillating current having a frequency of about 500 kHz to about 30 MHz. The heater may advantageously comprise a DC/AC inverter for converting the DC current supplied by the DC power supply into alternating current. The inductor coil may be arranged to generate a high-frequency oscillating electromagnetic field when receiving a high-frequency oscillating current from a power supply. The inductor coil may be arranged to generate a high frequency oscillating electromagnetic field within the device cavity. In some implementations, the inductor coil can substantially surround the device cavity. The inductor coil may extend at least partially along the length of the device cavity.

During use, the heater may be controlled to operate in a defined operating temperature range below the maximum operating temperature. An operating temperature range of about 150° C. to about 300° C. within the heating chamber (or device cavity) is preferred. The operating temperature range of the heater may be about 150°C to about 250°C.

Preferably, the operating temperature range of the heater may be from about 150°C to about 200°C. More preferably, the operating temperature range of the heater may be about 180°C to about 200°C.

The aerosol-generating device may include a power supply. The power supply may be a DC power supply. In some implementations, the power supply is a battery. The power supply may be a nickel-hydrogen alloy battery, a nickel cadmium battery, or a lithium-based battery, such as a lithium-cobalt, lithium-iron-phosphate or lithium-polymer battery. However, in some implementations, the power supply may be another type of charge storage device, such as a capacitor. The power supply may require recharging and may have a capacity to allow storage of sufficient energy for one or more user operations, such as one or more aerosol-generating experiences. For example, the power supply may have sufficient capacity to allow continuous heating of the aerosol-generating substrate for a period of about 6 minutes, corresponding to the typical time it takes to smoke a conventional cigarette, or for a 6-minute burnout period. You can. In another example, the power supply may have sufficient capacity to allow activation of a predetermined number of puffs or discrete heaters.

A non-exhaustive list of non-limiting examples is provided below. Any one or more features of these embodiments may be combined with any one or more features of other embodiments, implementations, or aspects described herein.

EX1. An aerosol-generating article comprising: an aerosol-generating rod extending from an upstream end to a downstream end; and a downstream section provided downstream of the aerosol-generating rod and abutting the downstream end of the aerosol-generating rod, wherein the aerosol-generating rod comprises a substantially cylindrical core portion having a longitudinal axis and surrounding the core portion and the core portion. It includes an annular portion extending coaxially with; wherein the annular portion is air permeable such that an upstream end within the annular portion is in fluid communication with the downstream section.

EX2. The aerosol-generating article of Example EX1, wherein the core portion comprises an aerosol-generating substrate and has an average porosity of 0.15 to 0.45.

EX3. The aerosol-generating article of Example EX1 or EX3, wherein the average porosity of the annular portion is at least 120% of the average porosity of the core portion.

EX4. The aerosol-generating article of any one of Examples EX1-EX3, wherein the downstream section comprises a hollow tubular element, the hollow tubular element defining an internal cavity and abutting the downstream end of the aerosol-generating rod.

EX5. The aerosol-generating article of EX4, wherein the inner diameter of the annular portion is smaller than the inner diameter of the hollow tubular element.

EX6. The method of EX4 or EX5, wherein the downstream section comprises a mouthpiece element downstream of the hollow tubular element, and the article further comprises a wrapper surrounding the aerosol-generating rod, the hollow tubular element, and the mouthpiece. Occurrence goods.

EX7. An aerosol-generating article according to any one of EX4 to EX6, comprising a ventilation zone at a location along the hollow tubular element.

EX8. The aerosol-generating article of any of the preceding embodiments, wherein the annular portion comprises linear, axially oriented fibers.

EX9. In EX 8, the fibers include cellulose acetate fibers, polylactic acid (PLA) fibers, polypropylene fibers, poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHVB) fibers, rayon fibers, viscose fibers, and recycled fibers. An aerosol-generating article selected from cellulosic fibers, and combinations thereof.

EX10. EX8 or EX9, wherein the annular portion comprises two or more longitudinal segments of tow material, and the tow material of adjacent ones of the two or more longitudinal segments are bonded together at least along a longitudinal edge of the segments. An aerosol-generating article forming an integral annular portion.

EX11. The aerosol-generating article of any of Examples 8-10, wherein the fibers have a denier per filament (dpf) from 3.0 dpf to 15.0 dpf.

EX12. 12. The aerosol-generating article of claim 11, wherein the fibers have a dpf of 5.0 dpf to 10.0 dpf.

EX13. The aerosol-generating article of any of Examples 8-12, wherein the fibers have different Y-shaped cross-sections.

EX14. The aerosol-generating article of any of the preceding embodiments, wherein the core portion has a cross-sectional porosity of 0.15 to 0.30.

EX15. The aerosol-generating article according to any of the preceding embodiments, wherein the core portion has a cross-sectional porosity distribution of 0.04 to 0.22.

EX16. The aerosol-generating article of any of the preceding embodiments, wherein the annular portion has a cross-sectional porosity of 0.3 to 0.95.

EX17. An aerosol-generating article according to any of the preceding embodiments, comprising a susceptor element arranged within the core portion and thermally coupled to the aerosol-generating substrate.

EX18. An aerosol-generating article according to any one of the preceding embodiments, wherein the aerosol-generating rod has a length between 10 mm and 35 mm.

EX19. An aerosol-generating article according to any of the preceding embodiments, wherein the hollow tubular element has a length between 10 mm and 35 mm.

EX20. The aerosol-generating article of any of the preceding embodiments, wherein the outer diameter of the article is between 4 mm and 10 mm.

EX21. An aerosol-generating article according to any of the preceding embodiments, wherein the annular portion radially abuts the core portion.

EX22. The aerosol-generating article of any of the preceding embodiments, wherein the outer diameter of the core portion is between 3 mm and 7 mm.

EX23. The aerosol-generating article of any of the preceding embodiments, wherein the outer diameter of the core portion is between 3.5 mm and 5.75 mm.

EX24. The aerosol-generating article of any of the preceding embodiments, wherein the overall length of the article is between 25 mm and 108 mm.

EX25. The aerosol-generating article of any of the preceding embodiments, wherein the overall length of the article is between 40 mm and 70 mm.

EX26. The aerosol-generating article of any of the preceding embodiments, wherein the RTD of the annular portion is from 10 mmH ₂ O to 65 mmH ₂ O.

EX27. The aerosol-generating article of any of the preceding embodiments, wherein the RTD of the annular portion is between 30 mmH ₂ O and 60 mmH ₂ O.

EX28. An aerosol-generating device comprising an aerosol-generating article according to any one of Examples 1 to 27 and an aerosol-generating device comprising a heating chamber open at the proximal end to at least partially receive the aerosol-generating rod for heating the aerosol-generating substrate. An aerosol-generating system, wherein the aerosol-generating device includes an opening at the distal end to allow airflow into the heating chamber along the longitudinal axis of the heating chamber, wherein the diameter of the opening is less than the inner diameter of the annular portion.

EX29. The aerosol of EX28, wherein when the aerosol-generating article is contained in the heating chamber and the upstream end of the aerosol-generating article abuts the distal end of the heating chamber, the RTD of the system is between 60 mmH ₂ O and 160 mmH ₂ O. Generating system.

In the following, the present invention will be further explained with reference to the accompanying drawings, wherein:
1 shows a schematic side cross-sectional view of an aerosol-generating article according to one embodiment of the invention;
Figure 2 shows a schematic cross-sectional view of the aerosol-generating article of Figure 1 taken along line IV-IV; and
Figure 3 shows a schematic side cross-sectional view of an aerosol-generating system according to an embodiment of the invention comprising the aerosol-generating article and aerosol-generating device of Figures 1 and 2;

The aerosol-generating article 10 shown in FIG. 1 includes an aerosol-generating rod 12 and a downstream section 14 positioned downstream of the aerosol-generating rod 12 . Accordingly, the aerosol-generating article 10 can be extended from an upstream or distal end 16 - substantially coincident with the upstream end of the aerosol-generating rod 12 - to a downstream or mouth end coincident with the downstream end of the downstream section 14 ( It has been extended to 18). The downstream section 14 includes a hollow tubular element 30 and a mouthpiece element 50. A wrapper (24) surrounds the aerosol-generating rod (12), the hollow tubular element (30) and the mouthpiece element (50).

The aerosol-generating article 10 has an overall length of approximately 45 mm and an outer diameter of approximately 7.7 mm.

The aerosol-generating rod has a length of 11 mm. The aerosol-generating rod includes a core portion 20 containing shredded tobacco material. More specifically, the core portion 20 includes homogenized tobacco material in the form of a sheet corrugated into a cylindrical shape, and the homogenized tobacco material includes 13% to 16% by weight of glycerin. The average porosity of the core portion is about 0.3. The aerosol-generating article 10 further comprises an elongated susceptor element 22 in the form of a plate embedded in and thermally coupled to the aerosol-generating substrate within the core portion 20.

The aerosol-generating rod further comprises an annular portion 24 surrounding the core portion 20 and radially abutting it. Accordingly, as shown in Figure 2, the inner diameter of the annular portion 24 substantially matches the outer diameter of the core portion.

The average porosity of the annular portion is 0.6. The annular portion is formed of a plurality of linear, axially oriented fibers of cellulose acetate.

The hollow tubular element 30 has a length of approximately 12 mm, an outer diameter of approximately 7.7 mm, and an internal diameter of approximately 5.5 mm. Accordingly, the thickness of the peripheral wall of the hollow tubular element 30 is approximately 1.1 mm.

The hollow tubular element 30 defines an internal cavity 32 extending completely from the upstream end of the hollow tubular element 30 to the downstream end of the hollow tubular element 30 . The internal cavity 32 is substantially empty, so that substantially unrestricted airflow is possible along the internal cavity 32 . The hollow tubular element 30 does not contribute substantially to the overall RTD of the aerosol-generating article 10.

Because the inner diameter of the hollow tubular element 30 is larger than the inner diameter of the annular portion 22, the annular portion 22 is in direct fluid communication with the internal cavity 32.

The aerosol-generating article (10) comprises a ventilation zone (40) provided at a location along the hollow tubular element (30). More specifically, ventilation zone 40 is provided approximately 26 mm from the downstream end of article 10. A ventilation zone 40 is provided 4 mm upstream from the upstream end of the mouthpiece element 50. The ventilation zone 40 comprises a circumferential row of openings or perforations surrounding the hollow tubular element 30 . Perforations in the ventilation zone 40 extend through the wall of the hollow tubular element 30 to allow fluid to enter the interior cavity 32 from the exterior of the article 10 . The ventilation level of the aerosol-generating article 10 is about 16%.

Mouthpiece element 50 extends from the downstream end of hollow tubular element 30 to the downstream or mouth end of aerosol-generating article 10. Mouthpiece element 50 has a length of approximately 22 mm. The outer diameter of the mouthpiece element 50 is approximately 7.7 mm. Mouthpiece element 50 includes a low density cellulose acetate filter portion. The RTD of mouthpiece element 50 is approximately 8 mmH ₂ O. Mouthpiece elements 50 may be individually packaged by plug wrap (not shown).

The aerosol-generating article further comprises an elongated susceptor (60) in the form of a rectangular strip provided within the core portion (20).

FIG. 3 shows an aerosol-generating system 100 including an exemplary aerosol-generating device 1 and an aerosol-generating article 10 equivalent to those shown in FIGS. 1 and 2 . In particular, Figure 3 shows the downstream mouth distal portion of the aerosol-generating device 1, where a device cavity is defined and the aerosol-generating article 10 can be accommodated.

The aerosol-generating device 1 includes a housing (or body) 4. The housing (4) comprises a peripheral wall (6) and an end wall (8). The peripheral wall 6 defines a device cavity for receiving the aerosol-generating article 10. The device cavity is defined by a closed distal end and an open mouth end. The mouth end of the device cavity is located at the mouth end of the aerosol-generating device (1). The aerosol-generating article 10 is configured to be received through a mouth end of the device cavity and is configured to abut a closed end of the device cavity.

A device airflow inlet (5) is defined within the distal wall (8). As shown by the dashed arrow in FIG. 3 , air may enter the core portion 20 through the device airflow inlet 5 . At the same time, since the diameter of the device airflow inlet 5 is smaller than the outer diameter of the core part 20, the distal wall surface 8 effectively occludes the distal surface of the annular part. In this way, while the airflow into the annular portion is deactivated, fluid communication is selectively established between the exterior of the aerosol-generating device 1 and the aerosol-generating substrate within the core portion 20 .

The aerosol-generating device (1) further comprises a heater element in the form of an induction coil (7) adapted to induce an electric current in the susceptor element (24). The aerosol generating device 1 further includes a power source (not shown) for supplying power to the heater. A controller (not shown) is also provided to control the supply of power to the heater. The heater is configured to controllably heat the aerosol-generating article 10 during use when the aerosol-generating article 1 is received within the device 1 .

For the purposes of this description and the appended claims, except where otherwise indicated, all numbers expressing quantities, quantities, percentages, etc. are to be understood in all instances as being modified by the term “about.” Additionally, all ranges include the maximum and minimum points disclosed and include therein any intermediate ranges that may or may not be specifically recited herein. Therefore, in this context, the number A is understood as 10% of A ± A. In this context, number A may be considered to include a numerical value that is within the typical standard error of measurement for the characteristic that number A modifies. In some instances as used in the appended claims, the number A may be varied by the percentages listed above, provided that the amount by which A is varied does not significantly affect the basic and novel feature(s) of the claimed invention. Additionally, all ranges include the maximum and minimum points disclosed and include therein any intermediate ranges that may or may not be specifically recited herein.

Claims (15)

As an aerosol-generating article,
an aerosol-generating rod extending from an upstream end to a downstream end; and
a downstream section provided downstream of the aerosol-generating rod and bordering the downstream end of the aerosol-generating rod,
the aerosol-generating rod comprising a substantially cylindrical core portion having a longitudinal axis and an annular portion surrounding the core portion and extending coaxially with the core portion;
the annular portion is permeable to air such that an upstream end within the annular portion is in fluid communication with the downstream section,
The core portion includes an aerosol-generating substrate and has a cross-sectional porosity of 0.10 to 0.45. and the cross-sectional porosity of the annular portion is at least 120% of the cross-sectional porosity of the core portion,
An aerosol-generating article, wherein the annular portion has a thickness of at least 0.5 mm. 2. An aerosol-generating article according to claim 1, wherein the downstream section comprises a hollow tubular element, the hollow tubular element defining an internal cavity and abutting the downstream end of the aerosol-generating rod. 3. An aerosol-generating article according to claim 2, wherein the inner diameter of the annular portion is less than the inner diameter of the hollow tubular element. 4. The method of claim 2 or 3, wherein the downstream section comprises a mouthpiece element downstream of the hollow tubular element, and the article further comprises a wrapper surrounding the aerosol-generating rod, the hollow tubular element and the mouthpiece. Aerosol-generating articles, including: An aerosol-generating article according to claim 2 , comprising a ventilation zone at a location along the hollow tubular element. An aerosol-generating article according to claim 1 , wherein the annular portion comprises linear, axially oriented fibers. The method of claim 6, wherein the fibers are cellulose acetate fibers, polylactic acid (PLA) fibers, polypropylene fibers, poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHVB) fibers, rayon fibers, viscose fibers, An aerosol-generating article selected from regenerated cellulose fibers, and combinations thereof. 8. The method of claim 6 or 7, wherein the annular portion comprises two or more longitudinal segments of tow material, and the tow material of adjacent ones of the two or more longitudinal segments extends at least along a longitudinal edge of the segment. An aerosol-generating article bonded together to form an integral annular portion. 9. An aerosol-generating article according to any one of claims 6 to 8, wherein the fibers have a denier per filament (dpf) of from 3.0 dpf to 15.0 dpf. 10. An aerosol-generating article according to any preceding claim, wherein the core portion has a cross-sectional porosity of 0.15 to 0.30. 11. An aerosol-generating article according to any preceding claim, wherein the core portion has a cross-sectional porosity distribution of 0.04 to 0.22. 12. An aerosol-generating article according to any preceding claim, wherein the annular portion has a cross-sectional porosity of from 0.3 to 0.95. 13. An aerosol-generating article according to any preceding claim, comprising a susceptor element arranged inside the core portion and thermally coupled to the aerosol-generating substrate. 14. An aerosol-generating article according to any preceding claim, wherein the annular portion radially abuts the core portion. An aerosol-generating article according to any one of claims 1 to 14 and an aerosol-generating device comprising a heating chamber open at the proximal end to at least partially receive the aerosol-generating rod for heating the aerosol-generating substrate. an aerosol-generating system, wherein the aerosol-generating device includes an opening at the distal end to allow airflow into the heating chamber along the longitudinal axis of the heating chamber, the diameter of the opening being less than the inner diameter of the annular portion, Generating system.