RU2849463C1 - Aerosol-generating device and method for its manufacture (variations) - Google Patents

Abstract

FIELD: tobacco indusrty.

SUBSTANCE: an aerosol-generating device (10) is provided for producing an inhalable aerosol upon heating, as well as variants of methods for its manufacture. The aerosol-generating device (10) comprises an aerosol-generating element (12) containing an aerosol-generating substrate. The aerosol-generating substrate contains homogenised tobacco material containing an aerosol-forming substance. The aerosol generating product further comprises a current collector (44) disposed within the aerosol generating element (12) and configured to heat the homogenised tobacco material. The current collector (44) is coated with a coating composition containing at least 20% by weight of an aerosol-forming substance. The coating composition further contains isolated nicotine and/or a monobasic nicotine salt.

EFFECT: elimination of the initial "cold draw" or "empty draw" effect, rapid delivery of aerosol to the user and ensuring its more precise adjustment during use.

14 cl, 3 dwg, 1 tbl

Description

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

Aerosol-generating articles in which an aerosol-generating substrate, such as a tobacco-containing substrate, is heated rather than combusted are known in the art. Typically, in such heated smoking articles, the aerosol is generated by heat transfer from a heat source to a physically separate aerosol-generating substrate or material, which may be located in contact with, within, around, 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 in air drawn through the aerosol-generating article. As the released compounds cool, they condense to 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 the aerosol is generated by transferring heat from one or more electrical heating elements of the aerosol-generating device to an aerosol-generating substrate of the heated aerosol-generating article. For example, electrically heated aerosol-generating devices have been proposed that comprise an internal heating plate that is adapted for insertion into an aerosol-generating substrate. Alternatively, document WO 2015/176898 proposes inductively heated aerosol-generating articles comprising an aerosol-generating substrate and a susceptor located within the aerosol-generating substrate.

Aerosol-generating products that heat rather than combust the tobacco-containing substrate present a number of challenges not encountered with conventional smoking products. First, tobacco-containing substrates are typically heated to significantly lower temperatures than those reached by the combustion front in a conventional cigarette. This can impact the release of nicotine from the tobacco-containing substrate and the delivery of nicotine to the consumer. At the same time, if the heating temperature is increased in an attempt to enhance nicotine delivery, the generated aerosol typically needs to be cooled to a greater extent and more quickly before reaching the consumer.

Secondly, heating the tobacco-containing aerosol-generating substrate, even to the temperature required for aerosol formation, typically takes some time, which can delay the aerosol's delivery to the consumer. This phenomenon, whereby when the user initially puffs on the product, the aerosol reaching the user may have a relatively low content of flavor, nicotine, or both, is often referred to as the "cold draw" or "empty draw" effect.

One such delay can be found, for example, in aerosol-generating rods and aerosol-generating articles where the aerosol-generating substrate contains homogenized tobacco material, as the aerosol-forming substance and nicotine may not be readily available for release. This may particularly occur when a formed sheet of homogenized tobacco material is used, formed from a suspension containing the aerosol-forming substance, as opposed to when the aerosol-forming substance is applied (e.g., sprayed) onto the formed sheet.

A previous proposal to address this issue was to provide two or more independent heating zones in the device, which heat the aerosol-generating rod or the aerosol-generating article. Since this allows for different heating profiles for different parts of the aerosol-generating substrate, it can help counteract the "cold puff" effect.

However, it would be desirable to provide new and improved aerosol-generating rods or aerosol-generating devices that are designed to eliminate the initial "cold draw" or "empty draw" effect. For example, it would be desirable to provide new and improved aerosol-generating rods or aerosol-generating devices that are capable of more quickly delivering satisfactory aerosol to the user and that allow for more precise control of aerosol delivery during use.

It would be particularly desirable to provide one such new and improved aerosol-generating rod or aerosol-generating article that can generate satisfactory aerosol delivery to the user at lower temperatures while still heating the tobacco-containing substrate for regular consumption.

In general, it is desirable to provide an aerosol generating product that is adapted to eliminate the initial “cold draw” or “empty draw” effect and that is convenient to use and can have improved practicality.

It would be desirable to provide one such aerosol generating rod or aerosol generating article that can be manufactured efficiently and at high speed without the need for extensive modification of existing equipment.

It would therefore be desirable to provide a new and improved aerosol generating article adapted to achieve at least one of the desired results described above.

The present invention relates to an aerosol-generating article for producing an inhalable aerosol upon heating. The aerosol-generating article may comprise an aerosol-generating element comprising an aerosol-generating substrate. The aerosol-generating substrate may comprise homogenized tobacco material comprising an aerosol-forming substance. The aerosol-generating article may further comprise a current collector located within the aerosol-generating element and configured to heat the homogenized tobacco material. The current collector may be coated with a coating composition. The coating composition may comprise at least 20% by weight of an aerosol-forming substance. The coating composition may further comprise isolated nicotine and/or a monobasic nicotine salt.

According to the present invention, there is provided an aerosol-generating article for producing an inhalable aerosol upon heating, wherein the aerosol-generating article comprises: an aerosol-generating element comprising an aerosol-generating substrate, wherein the aerosol-generating substrate comprises homogenized tobacco material comprising an aerosol-forming substance; and a current collector located within the aerosol-generating element and configured to heat the homogenized tobacco material, wherein the current collector is coated with a coating composition comprising at least 20 percent by weight of an aerosol-forming substance, wherein the coating composition further comprises isolated nicotine and/or a monobasic salt of nicotine.

Unlike existing aerosol-generating articles, aerosol-generating articles according to the present invention comprise a current collector coated with a coating composition containing a predetermined amount of an aerosol-forming substance and isolated nicotine and/or nicotine salt.

The inventors of the present invention have found that by thermally bonding a current collector coated with one of such compositions to a substrate generating an aerosol based on homogenized tobacco, it is advantageous to at least partially eliminate the initial delay in the generation and delivery of the aerosol often encountered in existing aerosol-generating articles.

Without being limited by theory, it should be understood that nicotine, whether in isolated form and/or as a monobasic acid salt, and the aerosol former in the coating composition are more accessible than the nicotine and aerosol former contained in the homogenized tobacco material. Furthermore, it is understood that during the initial heating cycle, the heat generated by induction via the susceptor is quickly and directly transferred to the coating composition, and therefore the first burst of nicotine-containing aerosol can be provided to the consumer, while the temperature of the majority of the substrate containing the homogenized tobacco material surrounding the coated susceptor continues to rise. Thus, when the aerosol from the homogenized tobacco material begins to be released at a satisfactory rate and with the desired flavor and nicotine content, this flow ensures a steady release of the aerosol for the remainder of the use cycle.

By adjusting the aerosol-forming substance and nicotine content of the composition, as well as the ratio between the aerosol-forming substance and nicotine content of the composition and the corresponding content in the homogenized tobacco material, it is advantageously possible to precisely adjust the transition from one aerosol source to another. In particular, this can be achieved so that the transition is particularly smooth and undetectable to the consumer.

Figure 1 qualitatively shows how the aerosol delivery from each of the homogenized tobacco substrate and the coating composition applied to the susceptor changes over time. As illustrated in Figure 1 by line A, the aerosol is rapidly released from the coating composition after the article begins to heat and quickly reaches a maximum before decreasing almost as quickly. The content of the aerosol species in the coating composition is depleted relatively quickly, and therefore the release of aerosol from the coating composition essentially ceases after a relatively short time. On the other hand, the release of aerosol from the homogenized tobacco substrate, represented by line B, is initially less significant, and only after the release of aerosol from the coating composition begins to decrease does the amount of aerosol released from the homogenized tobacco substrate reach a comparable level. By the time aerosol release from the coating composition has essentially ceased, the rate of aerosol release from the homogenized tobacco substrate will have more than doubled and will only gradually decrease over a longer period of time covering the remainder of the product's use cycle.

At any time during use, the consumer effectively experiences the sum of the flow of aerosol species released from the coating composition applied to the susceptor and the flow of aerosol species released from the homogenized tobacco substrate. Dashed line C in Figure 1 illustrates this effect during the initial portion of the product's use cycle. As the graph shows, aerosol release from the coating composition applied to the susceptor compensates for the initial delay in aerosol release from the homogenized tobacco substrate until the latter begins to substantially predominate. This is perceived by the consumer as an overall faster, more uniform, and more even delivery of aerosol throughout the product's use cycle compared to existing aerosol-generating products.

Methods will also be described for producing aerosol generating articles that provide one or more of the advantages discussed above on existing production lines without the need for significant reconfiguration of the lines.

As briefly described above, the present invention provides an aerosol-generating article for generating an inhalable aerosol upon heating. The aerosol-generating article comprises an aerosol-generating element containing an aerosol-generating substrate.

The term "aerosol-generating article" is used in this document to refer to an article in which an aerosol-generating substrate is heated to produce and deliver an inhalable aerosol to the user. For the purposes of this document, the term "aerosol-generating substrate" refers to a substrate capable of releasing volatile compounds when heated to generate an aerosol.

A conventional cigarette is ignited when the user applies a flame to one end of the cigarette and draws air through the other end. The localized heat provided by the flame and oxygen in the air drawn through the cigarette causes the end of the cigarette to ignite, and the resulting combustion generates inhaled smoke. In comparison, 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 the aerosol is generated by heat transfer from a combustible fuel element or heat source to a physically separate aerosol-generating material. For example, the aerosol-generating articles according to the present invention find particular application in aerosol-generating systems comprising an electrically heated aerosol-generating device having an internal heating plate adapted for insertion into the rod of an aerosol-generating substrate. Aerosol-generating articles of this type are described in the prior art, for example, in document EP 0 822 670.

As used herein, the term "aerosol generating device" refers to a device comprising a heating element that interacts with an aerosol generating substrate of an aerosol generating article to generate an aerosol.

The aerosol-generating element may be in the form of a rod. In the context of this document, the term "rod" is used to describe a substantially cylindrical element with a substantially circular, oval, or elliptical cross-section.

For the purposes of this document, the term "longitudinal" refers to the direction corresponding to the major longitudinal axis of the aerosol-generating article, which extends between the upstream and downstream ends of the aerosol-generating article. For the purposes of this document, the terms "upstream" and "downstream" describe the relative positions of elements or portions of elements of the aerosol-generating article relative to the direction in which the aerosol is transported through the aerosol-generating article during use.

During use, air is drawn through the aerosol-generating product in the longitudinal direction. The term "transverse" refers to the direction perpendicular to the longitudinal axis. Any reference to a "cross-section" of an aerosol-generating product or a component of an aerosol-generating product refers to the cross-section, unless otherwise specified.

The term "length" refers to the longitudinal dimension of an aerosol-generating component. For example, it can be used to describe the longitudinal dimension of a rod or elongated tubular elements.

An aerosol-generating substrate is a solid substrate that generates an aerosol. More specifically, an aerosol-generating substrate contains homogenized tobacco material.

Homogenized tobacco material is an example of "homogenized plant material." As used herein, the term "homogenized plant material" encompasses any plant material formed by agglomerating plant particles. For example, sheets or webs of homogenized tobacco material for aerosol-generating substrates according to the present invention can be formed by agglomerating tobacco material particles obtained by grinding, crushing, or grinding one or more tobacco leaf lamellas and tobacco leaf stems. Homogenized plant material can be produced by molding, extrusion, papermaking, or any other suitable processes known in the art.

The homogenized tobacco material may be provided in any suitable form. For example, the homogenized tobacco material may be in the form of one or more sheets. As used herein, the term "sheet" in relation to the present invention describes a layered element having a width and length substantially greater than its thickness. The homogenized tobacco material may be in the form of a plurality of pellets or granules.

Homogenized tobacco material may be in the form of multiple strands, strips, or pieces. For the purposes of this document, the term "strand" describes an elongated element of material whose length significantly exceeds its width and thickness. The term "strand" should be understood to encompass strips, pieces, and any other homogenized tobacco material of similar shape. Strands of homogenized tobacco material may be formed from a sheet of homogenized tobacco material, for example, by cutting or cutting into pieces, or by other methods, such as extrusion.

In some embodiments, the filaments may be formed in situ within the aerosol-generating substrate by separating or splitting a sheet of homogenized tobacco material during the formation of the aerosol-generating substrate, for example, by corrugating. The filaments of homogenized tobacco material in the aerosol-generating substrate may be separated from one another. Alternatively, each filament of homogenized tobacco material in the aerosol-generating substrate may be at least partially connected to an adjacent filament or filaments along the length of the filaments. For example, adjacent filaments may be connected via one or more fibers. This may occur, for example, if the filaments were formed by separating a sheet of homogenized tobacco material during the production of the aerosol-generating substrate, as described above.

Preferably, the aerosol-generating substrate is in the form of one or more sheets of homogenized tobacco material. In various embodiments of the present invention, the one or more sheets of homogenized tobacco material can be produced by a casting process. In various embodiments of the present invention, the one or more sheets of homogenized tobacco material can be produced by a papermaking process. Each of the one or more sheets, as described herein, can individually have a thickness of from 100 micrometers to 600 micrometers, preferably from 150 micrometers to 300 micrometers, and most preferably from 200 micrometers to 250 micrometers. Individual thickness refers to the thickness of an individual sheet, while cumulative 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, then the combined thickness is the sum of the thicknesses of the two separate sheets or the measured thickness of the two sheets when the two sheets are stacked on top of each other in the aerosol generating substrate.

Each of the one or more sheets as described herein may individually have a basis weight per square meter of from about 100 g/ ^m2 to about 300 g/ ^m2 .

Each of the one or more sheets as described herein may individually have a density of from about 0.3 g/ ^cm3 to about 1.3 g/ ^cm3 , and preferably from about 0.7 g/ ^cm3 to about 1.0 g/ ^cm3 .

In embodiments of the present invention in which the aerosol-generating substrate comprises one or more sheets of homogenized tobacco material, the sheets preferably have the form of one or more gathered sheets. As used herein, the term "gathered" means that the sheet of homogenized tobacco material is rolled, folded, or otherwise compressed or narrowed substantially transversely to the cylindrical axis of the rod or core.

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

One or more sheets of homogenized tobacco material may be advantageously corrugated or similarly processed. As used herein, the term "corrugated" refers to a sheet having a plurality of substantially parallel folds or corrugations. Alternatively or in addition to corrugation, one or more sheets of homogenized tobacco material may be embossed, blind-embossed, perforated, or otherwise deformed to provide texture on one or both sides of the sheet.

Preferably, each sheet of homogenized tobacco material may be corrugated such that it has a plurality of folds or corrugations substantially parallel to the cylindrical axis of the rod. This treatment advantageously facilitates the collection of the corrugated sheet of homogenized tobacco material to form a rod. Preferably, one or more sheets of homogenized tobacco material may be collected. It should be understood that the corrugated sheets of homogenized tobacco material may alternatively or additionally have a plurality of substantially parallel folds or corrugations located at an acute or obtuse angle to the cylindrical axis of the rod. The sheet may be corrugated to such an extent that the integrity of the sheet is disrupted at a plurality of parallel folds or corrugations, which results in separation of the material and leads to the formation of pieces, threads, or strips of homogenized tobacco material.

Alternatively, one or more sheets of homogenized tobacco material can be cut into strands, as mentioned above. In such embodiments, the aerosol-generating substrate comprises a plurality of strands of homogenized tobacco material. The strands can be used to form a rod. Typically, the width of such strands is approximately 5 millimeters, or approximately 4 millimeters, or approximately 3 millimeters, or approximately 2 millimeters or less. The length of the strands can be greater than approximately 5 millimeters, from approximately 5 millimeters to approximately 15 millimeters, from approximately 8 millimeters to approximately 12 millimeters, or approximately 12 millimeters. Preferably, the strands have substantially the same length relative to each other. The length of the strands can be determined by a manufacturing process by which the rod is cut into shorter rods, and the length of the strands corresponds to the length of the rod. The strands can be brittle, which can lead to breakage, especially during handling. In such cases, the length of some threads may be less than the length of the rod.

The plurality of threads preferably extend substantially longitudinally along the length of the aerosol-generating substrate, aligned with the longitudinal axis. Preferably, the plurality of threads are thus aligned substantially parallel to one another.

The homogenized tobacco material may contain up to about 95 percent by weight of plant particles on a dry weight basis. Preferably, the homogenized tobacco material contains up to about 90 percent by weight of plant particles, more preferably up to about 80 percent by weight of plant particles, more preferably up to about 70 percent by weight of plant particles, more preferably up to about 60 percent by weight of plant particles, more preferably up to about 50 percent by weight of plant particles on a dry weight basis.

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

The sheets of homogenized tobacco material for use in the present invention may have a tobacco content of at least about 40 percent by weight on a dry weight basis, more preferably at least about 50 percent by weight on a dry weight basis, more preferably at least about 70 percent by weight on a dry weight basis, and most preferably at least about 90 percent by weight on a dry weight basis.

For the purposes of the present invention, the term "tobacco particles" describes particles of any plant belonging to the genus Nicotiana. The term "tobacco particles" encompasses ground or powdered tobacco leaf lamellas, ground or powdered tobacco leaf stems, tobacco dust, tobacco fines, and other particulate tobacco by-products generated during the processing, handling, and shipping of tobacco. In a preferred embodiment, the tobacco particles are substantially all derived from tobacco leaf lamellas. By comparison, separated nicotine and nicotine salts are compounds derived from tobacco but are not considered tobacco particles for the purposes of the present invention and are not included in the percentage of particulate plant material.

Tobacco particles may be derived from one or more varieties of tobacco plants. Any type of tobacco may be used in the blend. Examples of tobacco types that may be used include, but are not limited to, sun-cured tobacco, flue-cured tobacco, Burley tobacco, Maryland tobacco, Oriental tobacco, Virginia tobacco, and other specialty tobaccos.

Flue-curing is a method of drying tobacco that is particularly widely used with Virginia tobacco varieties. During the flue-curing process, heated air is circulated through tightly packed tobacco. During the first stage, the tobacco leaves turn yellow and wilt. During the second stage, the leaf blades dry completely. During the third stage, the leaf stems dry completely.

Burley tobacco plays an important role in many tobacco blends. Burley tobacco has a distinctive flavor and aroma, and also has the ability to absorb large amounts of sauce.

Oriental tobacco has small leaves and pronounced aromatic qualities. However, it has a milder flavor than, for example, Burley tobacco. Consequently, Oriental tobacco is typically used in relatively small proportions in tobacco blends.

Kasturi, Maduro, and Yatim are subtypes of sun-cured tobacco that can be used. Preferably, Kasturi and flue-cured tobacco can be blended to produce tobacco particles. Accordingly, tobacco particles in particulate plant material may contain a mixture of Kasturi and flue-cured tobacco.

The tobacco particles may have a nicotine content of at least about 2.5 percent by weight on a dry weight basis. More preferably, the tobacco particles may have a nicotine content of at least about 3 percent, even more preferably at least about 3.2 percent, even more preferably at least about 3.5 percent, most preferably at least about 4 percent by weight on a dry weight basis.

In certain other embodiments of the present invention, the homogenized tobacco material may comprise tobacco particles in combination with non-tobacco botanical flavoring particles. Preferably, the non-tobacco botanical flavoring particles are selected from one or more of: ginger particles, eucalyptus particles, anise particles, and star anise particles. Preferably, in such embodiments, the homogenized tobacco material comprises at least about 2.5 percent by weight of non-tobacco botanical flavoring particles on a dry weight basis, with the remainder of the plant particles being tobacco particles. Preferably, the homogenized tobacco material contains at least about 4 percent by weight of non-tobacco plant flavoring particles, more preferably at least about 6 percent by weight of non-tobacco plant flavoring particles, more preferably at least about 8 percent by weight of non-tobacco plant flavoring particles, and more preferably at least about 10 percent by weight of non-tobacco plant flavoring particles, based on dry weight. Preferably, the homogenized tobacco material contains up to about 20 percent by weight of non-tobacco plant flavoring particles, more preferably up to about 18 percent by weight of non-tobacco plant flavoring particles, more preferably up to about 16 percent by weight of non-tobacco plant flavoring particles.

The weight ratio of the non-tobacco plant flavoring particles to the tobacco particles in the particulate plant material forming the homogenized tobacco material may vary depending on the desired flavor characteristics and the composition of the aerosol obtained from the aerosol-generating substrate during use. Preferably, the homogenized tobacco material contains at least a weight ratio of 1:30 non-tobacco plant flavoring particles to tobacco particles, more preferably at least a weight ratio of 1:20 non-tobacco plant flavoring particles to tobacco particles, more preferably at least a weight ratio of 1:10 non-tobacco plant flavoring particles to tobacco particles, and most preferably at least a weight ratio of 1:5 non-tobacco plant flavoring particles to tobacco particles, based on dry weight.

Homogenized tobacco material preferably contains no more than 95 percent particulate plant material by weight, based on dry weight. Therefore, particulate plant material is typically combined with one or more other components to form the homogenized tobacco material.

The homogenized tobacco material may further comprise a binder for altering the mechanical properties of the particulate plant material, wherein the binder is incorporated into the homogenized tobacco material during manufacturing, as described herein. Suitable exogenous binders are known to those skilled in the art and include, but are not limited to: gums such as, for example, guar gum, xanthan gum, acacia and locust bean gum; cellulose binders such as, for example, hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose and ethyl cellulose; polysaccharides such as, for example, starches, organic acids such as alginic acid, salts of conjugate bases with organic acids such as sodium alginate, agar and pectins; and combinations thereof. Preferably, the binder comprises guar gum.

The binder may be present in an amount of from about 1 percent to about 10 percent by weight based on the dry weight of the homogenized tobacco material, preferably in an amount of from about 2 percent to about 5 percent by weight based on the dry weight of the homogenized tobacco material.

Alternatively or additionally, the homogenized tobacco material may further comprise one or more lipids that promote the diffusibility of volatile components (e.g., aerosol forming agents, gingerols, and nicotine), wherein the lipid is included in the homogenized tobacco material during manufacture as described herein. Lipids suitable for inclusion in the homogenized tobacco material include, but are not limited to: medium chain triglycerides, cocoa butter, palm oil, palm kernel oil, mango butter, shea butter, soybean oil, cottonseed oil, coconut oil, hydrogenated coconut oil, candelilla wax, carnauba wax, shellac, sunflower wax, sunflower oil, rice bran wax, and Revel A; and combinations thereof.

Alternatively or additionally, the homogenized tobacco material may also contain a pH modifier.

Alternatively or additionally, the homogenized tobacco material may further comprise fibers to alter the mechanical properties of the homogenized tobacco material, wherein the fibers are incorporated into the homogenized tobacco material during manufacture as described herein. Suitable exogenous fibers for inclusion in the homogenized tobacco material are known in the art and include fibers formed from non-tobacco material and non-ginger material, including, but not limited to: cellulose fibers; softwood fibers; hardwood fibers; jute fibers; and combinations thereof. Exogenous fibers derived from tobacco and/or ginger may also be added. Any fibers added to the homogenized tobacco material are not considered to form part of the "particulate plant material" as defined above. Prior to incorporation into the homogenized tobacco material, the fibers may be processed by suitable processes known in the art, including, but not limited to: mechanical pulping; cleaning; chemical pulping; bleaching; sulfate conversion into fiber; and combinations thereof. The fiber is usually longer than it is wide.

Suitable fibers typically have lengths greater than 400 micrometers and less than or equal to 4 millimeters, preferably in the range of 0.7 millimeters to 4 millimeters. Preferably, the fibers are present in an amount of from about 2 percent to about 15 percent by weight, most preferably at a level of about 4 percent by weight, based on the dry weight of the substrate.

In the context of the present invention, the homogenized tobacco material further comprises one or more aerosol formers. After vaporization, the aerosol former can transfer other vaporized compounds released from the aerosol-generating substrate upon heating, such as nicotine and flavorings, into the aerosol. Aerosol formers suitable for inclusion in the homogenized tobacco 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 aerosol-forming substance content of the homogenized tobacco material may be from about 5 percent to about 30 percent by weight on a dry weight basis. Preferably, the homogenized tobacco material has an aerosol-forming substance content of at least about 10 percent by weight on a dry weight basis, more preferably at least about 15 percent by weight on a dry weight basis.

The homogenized tobacco material preferably has an aerosol forming substance content of less than or equal to about 25 percent by weight on a dry weight basis, more preferably less than or equal to about 20 percent by weight on a dry weight basis.

In some embodiments, the homogenized tobacco material has an aerosol forming agent content of from 5 percent to 25 percent by weight on a dry weight basis, preferably from 10 percent to 25 percent by weight on a dry weight basis, more preferably from 15 percent to 25 percent by weight on a dry weight basis. In other embodiments, the homogenized tobacco material has an aerosol forming agent content of from 5 percent to 20 percent by weight on a dry weight basis, preferably from 10 percent to 20 percent by weight on a dry weight basis, more preferably from 15 percent to 20 percent by weight on a dry weight basis.

In other embodiments, the homogenized tobacco material may have an aerosol-forming agent content of from about 30 percent by weight to about 45 percent by weight. This relatively high level of aerosol-forming agent is particularly suitable for aerosol-generating substrates that are intended to be heated at a temperature of less than 275 degrees Celsius. In such embodiments, the homogenized tobacco material preferably further comprises from about 2 percent by weight to about 10 percent by weight of a cellulose ether on a dry weight basis and from about 5 percent by weight to about 50 percent by weight of additional cellulose on a dry weight basis. It has been found that the use of a combination of a cellulose ether and additional cellulose provides particularly effective aerosol delivery when used in an aerosol-generating substrate having an aerosol-forming agent content of from 30 percent by weight to 45 percent by weight.

Suitable cellulose ethers include, but are not limited to, methylcellulose, hydroxypropylmethylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, ethylhydroxyethylcellulose, and carboxymethylcellulose (CMC). In particularly preferred embodiments, the cellulose ether is carboxymethylcellulose.

As used herein, the term "additional cellulose" encompasses any cellulosic material included in the homogenized tobacco material that is not derived from non-tobacco plant particles or tobacco particles present in the homogenized tobacco material. Therefore, additional cellulose is included in the homogenized tobacco material in addition to the non-tobacco plant material or tobacco material as a separate source of cellulose, distinct from any cellulose inherently present in the non-tobacco plant particles or tobacco particles. Additional cellulose is typically derived from a plant other than the non-tobacco plant particles or tobacco particles. Preferably, the additional cellulose is in the form of an inert cellulose material that is inert to the senses and, therefore, does not significantly affect the organoleptic characteristics of the aerosol generated from the aerosol-generating substrate. For example, the additional cellulose is preferably a tasteless and odorless material.

Supplemental cellulose may contain cellulose powder, cellulose fibers, or a combination of both.

The aerosol forming agent can act as a humectant in the aerosol generating substrate.

An aerosol-generating element containing an aerosol-generating substrate may be surrounded by a wrapper, which may be a paper wrapper or a non-paper wrapper. Paper wrappers suitable for use in certain embodiments of the present invention are known in the art and include, but are not limited to, types of cigarette paper; and filter filaments. Non-paper wrappers suitable for use in certain embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco materials. In certain preferred embodiments, the wrapper may be formed from a laminated material containing multiple layers. Preferably, the wrapper is formed from an aluminum multilayer sheet. The use of a multilayer sheet containing aluminum advantageously prevents the combustion of the aerosol-generating substrate in the event that the aerosol-generating substrate is ignited instead of heated in the intended manner.

As briefly described above, in the aerosol-generating article according to the present invention, the susceptor is located within the aerosol-generating element and is configured to heat an aerosol-generating substrate, such as homogenized tobacco material. Furthermore, the susceptor is coated with a coating composition, which will be described in more detail below.

In the context of this document, the term "susceptor" refers to a material capable of converting electromagnetic energy into heat. When placed within a fluctuating electromagnetic field, eddy currents induced in the susceptor cause the susceptor to heat up. Since the elongated susceptor is thermally coupled, for example, positioned in thermal contact with an aerosol-generating substrate, the aerosol-generating substrate is heated by the susceptor.

Preferably, the coated current collector is surrounded by an aerosol-generating substrate. In preferred embodiments, the coated current collector is surrounded by homogenized tobacco material, in particularly preferred embodiments, homogenized tobacco material.

Preferably, the current collector is oblong. When used to describe a current collector, the term "oblong" means that the current collector has a length that is greater than its width or thickness, for example, twice its width or thickness.

The current collector is preferably located substantially longitudinally within the aerosol-generating element. This means that the lengthwise dimension of the elongated current collector is approximately parallel to the longitudinal direction of the aerosol-generating element, for example, within plus or minus 10 degrees parallel to the longitudinal direction of the aerosol-generating element. In preferred embodiments, the elongated current collector may be located in a radially central position within the aerosol-generating element and extends along the longitudinal axis of the aerosol-generating element, particularly if the aerosol-generating element is formed as a rod.

For example, a coated elongated susceptor may be positioned substantially longitudinally within a rod of an aerosol-generating substrate containing homogenized tobacco material such that the susceptor is thermally coupled to the aerosol-generating substrate.

Preferably, the susceptor extends continuously to the downstream end of the aerosol-generating element. In some embodiments, the susceptor may extend continuously to the upstream end of the aerosol-generating element. In particularly preferred embodiments, the susceptor has substantially the same length as the aerosol-generating element and extends from the upstream end of the rod to the downstream end of the aerosol-generating element.

The current collector is preferably made in the form of a pin, rod, strip or plate.

The current collector preferably has a length of from about 5 millimeters to about 15 millimeters, such as from about 6 millimeters to about 12 millimeters, or from about 8 millimeters to about 10 millimeters.

The ratio between the length of the susceptor and the overall length of the aerosol generating article may be from about 0.2 to about 0.35.

Preferably, the ratio between the length of the susceptor and the total length of the aerosol-generating article is at least about 0.22, more preferably at least about 0.24, even more preferably at least about 0.26. The ratio between the length of the susceptor and the total length of the aerosol-generating article is preferably less than about 0.34, more preferably less than about 0.32, even more preferably less than about 0.3.

In some embodiments, the ratio between the length of the susceptor and the overall length of the aerosol-generating article is preferably from about 0.22 to about 0.34, more preferably from about 0.24 to about 0.34, even more preferably from about 0.26 to about 0.34. In other embodiments, the ratio between the length of the susceptor and the overall length of the aerosol-generating article is preferably from about 0.22 to about 0.32, more preferably from about 0.24 to about 0.32, even more preferably from about 0.26 to about 0.32. In further embodiments, the ratio between the length of the susceptor and the overall length of the aerosol-generating article is preferably from about 0.22 to about 0.3, more preferably from about 0.24 to about 0.3, even more preferably from about 0.26 to about 0.3.

In a particularly preferred embodiment, the ratio between the length of the current collector and the total length of the aerosol generating article is approximately 0.27.

The current collector preferably has a width of between approximately 1 millimeter and approximately 6 millimeters. More preferably, the current collector has a width of at least approximately 2 millimeters. Even more preferably, the current collector has a width of at least approximately 3 millimeters. In particularly preferred embodiments, the current collector has a width of approximately 4 millimeters or 5 millimeters. This is believed to maximize the surface area available for heat transfer while ensuring complete enclosure of the current collector by the aerosol-generating substrate.

The current collector may have a thickness of approximately 0.01 millimeters to approximately 2 millimeters, such as approximately 0.5 millimeters to approximately 2 millimeters. In some embodiments, the current collector preferably has a thickness of approximately 10 micrometers to approximately 500 micrometers, more preferably from approximately 10 micrometers to approximately 100 micrometers.

If the current collector has a constant cross-section, for example a circular cross-section, it has a preferred width or diameter of from approximately 1 millimeter to approximately 5 millimeters.

If the current collector is in the form of a strip or plate, the strip or plate is preferably rectangular with a width of approximately 2 millimeters to approximately 8 millimeters, more preferably from approximately 3 millimeters to approximately 5 millimeters. As an example, a current collector in the form of a strip or plate may have a width of approximately 4 millimeters.

If the current collector is in the form of a strip or plate, the strip or plate is preferably rectangular and has a thickness of approximately 0.03 millimeters to approximately 0.15 millimeters, more preferably from approximately 0.05 millimeters to approximately 0.09 millimeters. As an example, a current collector in the form of a strip or plate may have a thickness of approximately 0.07 millimeters.

In a preferred embodiment, the elongated current collector (in the form of a strip or plate, preferably has a rectangular shape and) has a thickness of from about 55 micrometers to about 65 micrometers.

More preferably, the elongated current collector has a thickness of approximately 57 micrometers to approximately 63 micrometers. Even more preferably, the elongated current collector has a thickness of approximately 58 micrometers to approximately 62 micrometers. In a particularly preferred embodiment, the elongated current collector has a thickness of approximately 60 micrometers.

Without being limited by theory, the present inventors believe that, in general, the selection of a given current collector thickness is also influenced by the constraints imposed by the chosen current collector length and width, as well as the constraints imposed by the geometry and dimensions of the aerosol-generating substrate rod. For example, the current collector length is preferably selected to match the length of the aerosol-generating element. The current collector width should preferably be selected to prevent displacement of the current collector within the substrate while simultaneously allowing for easy insertion during fabrication.

The inventors of the present invention have discovered that an aerosol-generating article in which a susceptor having a thickness in the range described above is provided for inductive heat transfer during use can advantageously generate and distribute heat across the aerosol-generating substrate particularly efficiently and optimally. Without being limited by theory, the inventors believe that this is due to the fact that such a susceptor is adapted to ensure optimal heat generation and heat transfer due to the susceptor's surface area and inductive power. In comparison, a thinner susceptor may be too easily deformed and may not maintain the desired shape and orientation within the aerosol-generating substrate during manufacture of the aerosol-generating article, which may result in a less uniform and less precisely tuned heat distribution during use. At the same time, a thicker susceptor may be more difficult to cut to the required length accurately and consistently, and this may also impact how accurately the susceptor can be aligned longitudinally within the aerosol-generating substrate rod, thereby potentially affecting the uniformity of heat distribution within the rod. These advantageous effects are particularly noticeable when the susceptor extends continuously to the downstream end of the aerosol-generating article rod. This is believed to be due to the fact that the resistance to draw (RTD) downstream of the susceptor can be minimized, as there is no aerosol-generating substrate within the rod at a location downstream of the susceptor that could contribute to RTD.

Without being limited by theory, the inventors believe that the downstream portion of an aerosol-generating element can act to some extent as a filter relative to upstream portions of the aerosol-generating element. Therefore, the inventors believe that it is desirable to be able to uniformly heat the downstream portion of an aerosol-generating element to actively engage it in the release of volatile aerosol species and facilitate overall aerosol generation and delivery, and that any potential filtering effect that could impede aerosol delivery to the consumer is reliably eliminated by the release of volatile aerosol species throughout the aerosol-generating element.

The current collector can be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from the aerosol-generating substrate. Preferred current collectors comprise metal or carbon.

A preferred current collector may comprise or be composed of a ferromagnetic material, such as a ferromagnetic alloy, ferritic iron, ferromagnetic steel, or stainless steel. A suitable current collector may be made of or comprise aluminum. Preferred current collectors may be formed from 400-series stainless steels, such as Type 410, Type 420, or Type 430 stainless steel. Different materials will dissipate different amounts of energy when placed within electromagnetic fields of similar frequency and field strength.

Thus, all current collector parameters, such as material type, length, width, and thickness, can be adjusted to achieve the desired power dissipation within a known electromagnetic field. Preferred current collectors can be heated to temperatures exceeding 250 degrees Celsius.

Suitable current collectors may comprise a non-metallic core with a metallic layer located on the non-metallic core, for example, with metallic traces formed on the surface of a ceramic core. The current collector may have a protective outer layer, such as a protective ceramic layer or a protective glass layer, enclosing the current collector. The current collector may comprise a protective layer formed of glass, ceramic, or an inert metal and extending over the core of the current collector material.

The current collector is positioned so as to be thermally coupled to the aerosol-generating substrate. Thus, when the current collector is heated, the aerosol-generating substrate is heated, and an aerosol is formed.

The current collector may be a multi-material current collector and may comprise a first current collector material and a second current collector material. The first current collector material is in direct physical contact with the second current collector material. The second current collector material preferably has a Curie temperature below 500 degrees Celsius. The first current collector material is preferably used primarily to heat the current collector when the current collector is placed in a fluctuating electromagnetic field. Any suitable material may be used. For example, the first current collector material may be aluminum or a ferrous metal such as stainless steel. The second current collector material is preferably used primarily to indicate that the current collector has reached a specific temperature, where this temperature is the Curie temperature of the second current collector material. The Curie temperature of the second current collector material may be used to regulate the temperature of the entire current collector during operation. Therefore, the Curie temperature of the second current-collecting material must be below the ignition point of the aerosol-generating substrate. Suitable materials for the second current-collecting material include nickel and certain nickel alloys.

By providing a current collector having at least a first and a second current collector material, wherein either the second current collector material has a Curie temperature and the first current collector material does not have a Curie temperature, or the first and second current collector materials have different first and second Curie temperatures, it is possible to separate the heating of the aerosol-generating substrate and control the heating temperature. The first current collector material is preferably a magnetic material having a Curie temperature greater than 500 degrees Celsius. From the standpoint of heating efficiency, it is desirable that the Curie temperature of the first current collector material exceed any maximum temperature to which the current collector should be able to heat. The second Curie temperature can preferably be selected to be below 400 degrees Celsius, preferably below 380 degrees Celsius, or below 360 degrees Celsius. Preferably, the second current-collecting material is a magnetic material selected such that it has a second Curie temperature that substantially coincides with the desired maximum heating temperature. That is, it is preferable that the second Curie temperature be approximately the same as the temperature to which the current-collecting material must be heated to generate an aerosol from the aerosol-generating substrate. The second Curie temperature may, for example, be within the range of 200 degrees Celsius to 400 degrees Celsius or 250 degrees Celsius to 360 degrees Celsius. The second Curie temperature of the second current-collecting material may, for example, be selected such that, when heated by a current-collecting material at a temperature equal to the second Curie temperature, the overall average temperature of the aerosol-generating substrate does not exceed 240 degrees Celsius.

In those embodiments where the current collector is in the form of a strip or plate, the mass per square meter of the current collector may be at least about 350 grams per square meter, preferably at least about 400 grams per square meter, more preferably at least about 450 grams per square meter. Preferably, in such embodiments, the mass per square meter of the current collector is less than or equal to about 650 grams per square meter, more preferably less than or equal to about 600 grams per square meter, even more preferably less than or equal to about 550 grams per square meter. In certain preferred embodiments, the mass per square meter of the current collector is approximately 500 grams per square meter.

In the aerosol-generating article according to the present invention, the susceptor may have a density of at least about 5 grams per cubic centimeter, preferably at least about 6 grams per cubic centimeter, more preferably at least about 7 grams per cubic centimeter. The susceptor preferably has a density of less than or equal to about 11 grams per cubic centimeter, more preferably less than or equal to about 10 grams per cubic centimeter, even more preferably less than or equal to about 9 grams per cubic centimeter. In certain preferred embodiments, the susceptor has a density of about 8 grams per cubic centimeter.

In the aerosol-generating article of the present invention, the current collector is coated with a coating composition. As used herein, the term "coated" means that a layer containing the coating composition is formed on the outer surface of the current collector. This is not limited by the mechanism or method for forming or applying the coating to the outer surface of the current collector. For example, the coating composition can be applied to the outer surface of the current collector by spraying, dipping, or extruding the coating composition onto the current collector.

In some embodiments, the entire outer surface of the current collector is coated. This can also be described as a "continuous coating." In other embodiments, only a portion of the outer surface of the current collector is coated. This can also be described as a "discontinuous coating," since the coating effectively forms coated and uncoated areas on the outer surface of the current collector.

Preferably, at least 50 percent of the outer surface area of the current collector is coated with the coating composition. More preferably, at least 75 percent of the outer surface area of the current collector is coated with the coating composition. Even more preferably, at least 90 percent of the outer surface area of the current collector is coated with the coating composition. More preferably, at least 95 percent of the outer surface area of the current collector is coated with the coating composition. In some particularly preferred embodiments, substantially the entire outer surface area of the current collector is coated with the coating composition.

The coating composition forms a layer on the outer surface of the current collector. The coating layer thickness can be controlled by adjusting parameters such as the viscosity of the slurry before application. Furthermore, various application methods, such as dipping and spraying, can be used to selectively control the coating layer thickness.

The coating composition layer may have a thickness of at least 1 micrometer. Preferably, the coating composition layer has a thickness of at least 2 micrometers, more preferably at least 3 micrometers, and even more preferably at least 4 micrometers. In particularly preferred embodiments, the coating composition layer has a thickness of at least about 5 micrometers, more preferably about 6 micrometers.

The coating composition layer may have a thickness of up to about 100 micrometers. Preferably, the coating composition layer has a thickness of less than or equal to about 50 micrometers, more preferably less than or equal to about 30 micrometers, and even more preferably less than or equal to about 15 micrometers. In particularly preferred embodiments, the coating composition layer has a thickness of less than or equal to about 12 micrometers, more preferably less than or equal to about 10 micrometers.

In some embodiments, the layer of the coating composition has a thickness of from about 2 micrometers to about 50 micrometers, preferably from about 3 micrometers to about 50 micrometers, more preferably from about 4 micrometers to about 50 micrometers, even more preferably from about 5 micrometers to about 50 micrometers, most preferably from about 6 micrometers to about 50 micrometers. In other embodiments, the layer of the coating composition has a thickness of from about 2 micrometers to about 30 micrometers, preferably from about 3 micrometers to about 30 micrometers, more preferably from about 4 micrometers to about 30 micrometers, even more preferably from about 5 micrometers to about 30 micrometers, most preferably from about 6 micrometers to about 30 micrometers. In further embodiments, the layer of the coating composition has a thickness of from about 2 micrometers to about 15 micrometers, preferably from about 3 micrometers to about 15 micrometers, more preferably from about 4 micrometers to about 15 micrometers, even more preferably from about 5 micrometers to about 15 micrometers, most preferably from about 6 micrometers to about 15 micrometers. In further embodiments, the layer of the coating composition has a thickness of from about 2 micrometers to about 12 micrometers, preferably from about 3 micrometers to about 12 micrometers, more preferably from about 4 micrometers to about 12 micrometers, even more preferably from about 5 micrometers to about 30 micrometers, most preferably from about 6 micrometers to about 12 micrometers. In still further embodiments, the layer of coating composition has a thickness of from about 2 micrometers to about 10 micrometers, preferably from about 3 micrometers to about 10 micrometers, more preferably from about 4 micrometers to about 10 micrometers, even more preferably from about 5 micrometers to about 10 micrometers, most preferably from about 6 micrometers to about 10 micrometers.

The total weight of the coating composition present in the aerosol-generating article according to the present invention can be from about 1 milligram to about 4 milligrams, preferably from about 1 milligram to about 3 milligrams, more preferably from about 1 milligram to about 2 milligrams.

The sum of the total weight of the aerosol-generating substrate in the aerosol-generating element and the total weight of the coating composition in the aerosol-generating article according to the present invention may be from about 150 milligrams to about 500 milligrams, preferably from about 180 milligrams to about 400 milligrams, more preferably from about 200 milligrams to about 300 milligrams. In certain preferred embodiments, the sum of the total weight of the aerosol-generating substrate in the aerosol-generating element and the total weight of the coating composition is about 250 milligrams.

As previously mentioned, in the aerosol-generating articles of the present invention, the coating composition comprises at least 20 percent by weight of an aerosol-forming agent. Furthermore, the coating composition comprises isolated nicotine and/or a monobasic nicotine salt. When heated, the coating composition described herein is designed to deliver a nicotine-containing aerosol to the lungs at an inhalation or airflow rate within the inhalation or airflow rate range of a typical smoking regimen.

The coating composition preferably comprises from about 0.5 percent by weight to about 10 percent by weight of isolated nicotine and/or nicotine monobasic salt. More preferably, the coating composition comprises from about 1 percent by weight to about 3 percent by weight of isolated nicotine and/or nicotine monobasic salt. Even more preferably, the coating composition comprises from about 1.5 percent by weight to about 2.5 percent by weight of isolated nicotine and/or nicotine monobasic salt. In some preferred embodiments, the coating composition comprises about 1.5 percent by weight of isolated nicotine and/or nicotine monobasic salt. The coating composition may comprise about 2 percent by weight of isolated nicotine and/or nicotine monobasic salt.

The nicotine component of the coating composition may be the most volatile component of the coating composition. In some aspects, water may be the most volatile component of the coating composition, and the nicotine component of the coating composition may be the second most volatile component of the coating composition.

As described above, the aerosol-generating substrate comprises homogenized tobacco material containing an aerosol-forming substance. Consequently, the total weight of nicotine in the aerosol-generating article will substantially correspond to the sum of the nicotine content of the coating composition and the nicotine content of the homogenized tobacco material. The nicotine content of the coating composition may be at least about 0.1 percent by weight of the total nicotine content of the aerosol-generating article as a whole. Preferably, the nicotine content of the coating composition is at least about 0.25 percent by weight of the total nicotine content of the aerosol-generating article as a whole. More preferably, the nicotine content of the coating composition is at least about 0.5 percent by weight of the total nicotine content of the aerosol-generating article as a whole.

The nicotine content of the coating composition is preferably less than or equal to about 10 percent by weight of the total nicotine content of the aerosol-generating article as a whole. More preferably, the nicotine content of the coating composition is less than or equal to about 5 percent by weight of the total nicotine content of the aerosol-generating article as a whole. Even more preferably, the nicotine content of the coating composition is less than or equal to 2 percent by weight of the total nicotine content of the aerosol-generating article as a whole.

In some embodiments, the nicotine content of the coating composition is preferably from about 0.1 to about 10 percent by weight of the total nicotine content of the aerosol-generating article as a whole. Preferably, the nicotine content of the coating composition is preferably from about 0.25 to about 10 percent by weight of the total nicotine content of the aerosol-generating article as a whole. More preferably, the nicotine content of the coating composition is preferably from about 0.5 to about 10 percent by weight of the total nicotine content of the aerosol-generating article as a whole. In other embodiments, the nicotine content of the coating composition is preferably from about 0.1 to about 15 percent by weight of the total nicotine content of the aerosol-generating article as a whole. Preferably, the nicotine content of the coating composition is preferably from about 0.25 to about 5 percent by weight of the total nicotine content of the aerosol-generating article as a whole. More preferably, the nicotine content of the coating composition is preferably from about 0.5 to about 5 percent by weight of the total nicotine content of the aerosol-generating article as a whole. In further embodiments, the nicotine content of the coating composition is preferably from about 0.1 to about 2 percent by weight of the total nicotine content of the aerosol-generating article as a whole. Preferably, the nicotine content of the coating composition is preferably from about 0.25 to about 2 percent by weight of the total nicotine content of the aerosol-generating article as a whole. More preferably, the nicotine content of the coating composition is preferably from about 0.5 to about 2 percent by weight of the total nicotine content of the aerosol-generating article as a whole.

The coating composition comprises an aerosol former. Ideally, the aerosol former is substantially resistant to thermal decomposition at the operating temperature of the associated aerosol-generating device. Suitable aerosol formers include, but are not limited to: polyhydric alcohols such as triethylene 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 polyhydric alcohols or mixtures thereof may be one or more of the following: triethylene glycol, 1,3-butanediol, and glycerol (glycerol or propane-1,2,3-triol), or polyethylene glycol. The aerosol former is preferably glycerol.

As briefly described above, the coating composition comprises at least 20 percent by weight of an aerosol former. The coating composition may comprise from about 20 percent by weight of an aerosol former to about 90 percent by weight of an aerosol former, such as from about 30 percent by weight of an aerosol former to about 80 percent by weight of an aerosol former, or from about 40 percent by weight of an aerosol former to 70 percent by weight of an aerosol former. In some preferred embodiments, the coating composition may comprise about 50 percent by weight of an aerosol former.

In particular, the composition may comprise from about 20 percent by weight glycerol to about 90 percent by weight glycerol, such as from about 30 percent by weight glycerol to about 80 percent by weight glycerol, or from about 40 percent by weight glycerol to 70 percent by weight glycerol. In some preferred embodiments, the coating composition may comprise about 50 percent by weight glycerol.

The coating composition may contain a majority of an aerosol former. The coating composition may contain a mixture of water and an aerosol former, wherein the aerosol former forms a majority (by weight) of the coating composition. The aerosol former may form at least about 50 percent by weight of the coating composition. The aerosol former may form at least about 60 percent by weight, or at least about 65 percent by weight, or at least about 70 percent by weight of the coating composition. The aerosol former may form from about 70 percent by weight to about 80 percent by weight of the coating composition. The aerosol former may form from about 70 percent by weight to about 75 percent by weight of the coating composition.

The coating composition may, in particular, contain a majority of glycerol. The coating composition may comprise a mixture of water and glycerol, wherein glycerol forms the majority (by weight) of the coating composition. Glycerol may form at least about 50 percent by weight of the coating composition. Glycerol may form at least about 60 percent by weight, or at least about 65 percent by weight, or at least about 70 percent by weight of the coating composition. Glycerol may form from about 70 percent by weight to about 80 percent by weight of the coating composition.

Glycerol may form from about 70 percent by weight to about 75 percent by weight of the coating composition.

As described above, the aerosol-generating substrate comprises homogenized tobacco material containing an aerosol-forming substance. Consequently, the total aerosol-forming substance content in the aerosol-generating article will substantially correspond to the sum of the aerosol-forming substance content in the coating composition and the aerosol-forming substance content in the homogenized tobacco material.

The content of the aerosol forming agent in the coating composition may be at least about 0.1 percent by weight of the total content of the aerosol forming agent in the aerosol-generating article as a whole. Preferably, the content of the aerosol forming agent in the coating composition is at least about 0.25 percent by weight of the total content of the aerosol forming agent in the aerosol-generating article as a whole. More preferably, the content of the aerosol forming agent in the coating composition is at least about 0.5 percent by weight of the total content of the aerosol forming agent in the aerosol-generating article as a whole.

The content of the aerosol forming agent in the coating composition is preferably less than or equal to about 10 percent by weight of the total content of the aerosol forming agent in the aerosol-generating article as a whole. More preferably, the content of the aerosol forming agent in the coating composition is less than or equal to about 5 percent by weight of the total content of the aerosol forming agent in the aerosol-generating article as a whole. Even more preferably, the content of the aerosol forming agent in the coating composition is less than or equal to 2 percent by weight of the total content of the aerosol forming agent in the aerosol-generating article as a whole.

In some embodiments, the content of the aerosol former in the coating composition is preferably from about 0.1 to about 10 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. Preferably, the content of the aerosol former in the coating composition is preferably from about 0.25 to about 10 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. More preferably, the content of the aerosol former in the coating composition is preferably from about 0.5 to about 10 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. In other embodiments, the content of the aerosol former in the coating composition is preferably from about 0.1 to about 15 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. Preferably, the content of the aerosol former in the coating composition is preferably from about 0.25 to about 5 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. More preferably, the content of the aerosol former in the coating composition is preferably from about 0.5 to about 5 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. In further embodiments, the content of the aerosol former in the coating composition is preferably from about 0.1 to about 2 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. Preferably, the content of the aerosol former in the coating composition is preferably from about 0.25 to about 2 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. More preferably, the content of the aerosol former in the coating composition is preferably from about 0.5 to about 2 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole.

In preferred embodiments, the glycerol content of the coating composition may be at least about 0.1 percent by weight of the total aerosol forming agent content of the aerosol-generating article as a whole. Preferably, the glycerol content of the coating composition is at least about 0.25 percent by weight of the total aerosol forming agent content of the aerosol-generating article as a whole. More preferably, the glycerol content of the coating composition is at least about 0.5 percent by weight of the total aerosol forming agent content of the aerosol-generating article as a whole.

The glycerol content of the coating composition is preferably less than or equal to about 10 percent by weight of the total aerosol-forming agent content in the aerosol-generating article as a whole. More preferably, the glycerol content of the coating composition is less than or equal to about 5 percent by weight of the total aerosol-forming agent content in the aerosol-generating article as a whole. Even more preferably, the glycerol content of the coating composition is less than or equal to 2 percent by weight of the total aerosol-forming agent content in the aerosol-generating article as a whole.

In some preferred embodiments, the glycerol content of the coating composition is preferably from about 0.1 to about 10 percent by weight of the total aerosol former content of the aerosol-generating article as a whole. Preferably, the glycerol content of the coating composition is preferably from about 0.25 to about 10 percent by weight of the total aerosol former content of the aerosol-generating article as a whole. More preferably, the glycerol content of the coating composition is preferably from about 0.5 to about 10 percent by weight of the total aerosol former content of the aerosol-generating article as a whole. In other embodiments, the glycerol content of the coating composition is preferably from about 0.1 to about 15 percent by weight of the total aerosol former content of the aerosol-generating article as a whole. Preferably, the glycerol content in the coating composition is preferably from about 0.25 to about 5 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. More preferably, the glycerol content in the coating composition is preferably from about 0.5 to about 5 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. In further embodiments, the glycerol content in the coating composition is preferably from about 0.1 to about 2 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. Preferably, the glycerol content in the coating composition is preferably from about 0.25 to about 2 percent by weight of the total content of the aerosol former in the aerosol-generating article as a whole. More preferably, the glycerol content in the coating composition is preferably from about 0.5 to about 2 percent by weight of the total aerosol forming agent content in the aerosol-generating article as a whole.

In certain preferred embodiments of the present invention, the coating composition further comprises at least one gelling agent. In other words, the coating composition is preferably a gel composition. Preferably, the at least one gelling agent forms a solid medium, and the aerosol-forming agent is distributed in the solid medium, wherein the released nicotine and/or monobasic nicotine salt are distributed in the aerosol-forming agent.

The term "gelling agent" refers to a compound that, when uniformly added to a 50 percent by weight water/50 percent by weight glycerol mixture in an amount of approximately 0.3 percent by weight, forms a solid medium or support matrix resulting in gel formation. Gelling agents include, but are not limited to, gelling agents that provide cross-linking via hydrogen bonds and gelling agents that provide cross-linking via ionic bonds.

The gelling agent may include one or more biopolymers. The biopolymers may be formed from polysaccharides.

Biopolymers include, for example, gellan gums (natural, low acyl gellan gum, high acyl gellan gums, with low acyl gellan gum being preferred), xanthan gum, alginates (alginic acid), agar, guar gum, and the like. The composition may preferably include xanthan gum. The composition may include two biopolymers. The composition may include three biopolymers. The composition may include two biopolymers in substantially equal weights. The composition may include three biopolymers in substantially equal weights.

Preferably, the gel composition comprises a stable gel phase. Advantageously, a stable nicotine-containing gel composition provides a predictable composition shape during storage or transportation from manufacturing to the consumer. A stable nicotine-containing gel composition essentially maintains its shape. A stable nicotine-containing gel composition essentially does not release its liquid phase during storage or transportation from manufacturing to the consumer. A stable nicotine-containing gel composition can provide a simple consumable design. This consumable can be designed without liquid, thus allowing for a wider range of container materials and designs.

The phrase "stable gel phase" or "stable gel" refers to a gel that substantially maintains its shape and mass when exposed to varying environmental conditions. A stable gel may not release (release moisture) or absorb water when exposed to standard temperature and pressure with relative humidity varying from approximately 10 percent to approximately 60 percent. For example, a stable gel may substantially maintain its shape and mass when exposed to standard temperature and pressure with relative humidity varying from approximately 10 percent to approximately 60 percent.

The coating composition preferably comprises one or more gelling agents. In certain preferred embodiments, the gelling agent comprises carboxymethylcellulose (CMC) and/or hydroxypropylmethylcellulose (HPMC). Preferably, in these embodiments, the aerosol former comprises glycerin.

Preferably, the coating composition contains a total amount of gelling agents in the range of from about 0.4 percent by weight to about 10 percent by weight. More preferably, the coating composition contains gelling agents in the range of from about 0.5 percent by weight to about 8 percent by weight. More preferably, the coating composition contains gelling agents in the range of from about 1 percent by weight to about 6 percent by weight. More preferably, the coating composition contains gelling agents in the range of from about 2 percent by weight to about 4 percent by weight. More preferably, the coating composition contains gelling agents in the range of from about 2 percent by weight to about 3 percent by weight.

The aerosol-generating article according to the present invention preferably further comprises a downstream section at a location downstream of the aerosol-generating element. As will be apparent from the following description of various embodiments of the aerosol-generating article according to the present invention, the downstream section may comprise one or more downstream elements.

The downstream section may comprise a support element aligned with and downstream of the aerosol-generating element. Specifically, the support element may be located directly downstream of the aerosol-generating element and may be adjacent to the core of the aerosol-generating substrate.

The support element may be formed from any suitable material or combination of materials. For example, the support element may be formed from one or more materials selected from the group consisting of: cellulose acetate; cardboard; corrugated paper, such as corrugated heat-resistant paper or corrugated parchment paper; and polymeric materials, such as low-density polyethylene (LDPE). In a preferred embodiment, the support element is formed from cellulose acetate. Other suitable materials include polyhydroxyalkanoate (PHA) fibers.

The support element may comprise a hollow tubular segment. In a preferred embodiment, the support element comprises a hollow tube made of cellulose acetate.

The support element is positioned substantially in alignment with the rod. This means that the length of the support element is approximately parallel to the longitudinal direction of the rod and the article, for example, within plus or minus 10 degrees parallel to the longitudinal direction of the rod. In preferred embodiments, the support element extends along the longitudinal axis of the rod.

The support member preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating substrate rod and the outer diameter of the aerosol-generating article.

The support element may have an outer diameter of 5 millimeters to 12 millimeters, for example, 5 millimeters to 10 millimeters, or 6 millimeters to 8 millimeters. In a preferred embodiment, the support element has an outer diameter of 7.2 millimeters plus or minus 10 percent.

The peripheral wall of the support element may have a thickness of at least 1 millimeter, preferably at least about 1.5 millimeters, more preferably at least about 2 millimeters.

The support member may have a length of from approximately 5 millimeters to approximately 15 millimeters.

Preferably, the support member has a length of at least about 6 millimeters, more preferably at least about 7 millimeters.

In preferred embodiments, the support member has a length of less than about 12 millimeters, more preferably less than about 10 millimeters.

In some embodiments, the support element has a length of from about 5 millimeters to about 15 millimeters, more preferably from about 6 millimeters to about 15 millimeters, more preferably from about 7 millimeters to about 15 millimeters. In other embodiments, the support element has a length of from about 5 millimeters to about 12 millimeters, preferably from about 6 millimeters to about 12 millimeters, more preferably from about 7 millimeters to about 12 millimeters. In further embodiments, the support element has a length of from about 5 millimeters to about 10 millimeters, preferably from about 6 millimeters to about 10 millimeters, more preferably from about 7 millimeters to about 10 millimeters.

In a preferred embodiment, the support member has a length of approximately 8 millimeters.

Preferably, the overall length of the intermediate hollow section is no more than about 18 millimeters, more preferably no more than about 17 millimeters, more preferably no more than 16 millimeters.

Preferably, in the aerosol-generating articles of the present invention, the support element has an average radial hardness of at least about 80 percent, more preferably at least about 85 percent, even more preferably at least about 90 percent. Accordingly, the support element is capable of providing the desired level of hardness to the aerosol-generating article. If necessary, the radial hardness of a component, such as the support element of a downstream section of the aerosol-generating articles of the present invention, can be further increased by surrounding the aerosol-cooling element with a rigid filament, such as a filament having a basis weight of at least about 80 grams per square meter (g/ ^m2 ), or at least about 100 g/ ^m2 , or at least about 110 g/ ^m2 .

In the context of this document, the term "radial hardness" refers to the resistance to compression in the direction transverse to the longitudinal axis of the support element. The radial hardness of an aerosol-generating article around the support element can be determined by applying a load along the article at the location of the support element transverse to the article's longitudinal axis and measuring the average (mean) compressed diameters of the articles. Radial hardness is determined as follows:

Radial hardness (%) = (D _d /D _s ) * 100

where D _s is the original (uncompressed) diameter, and D _d is the compressed diameter after applying a specified load for a specified period of time. The harder the material, the closer the hardness is to 100 percent.

To determine the hardness of a portion (such as a support element provided in the form of a hollow tubular segment) of an aerosol product, the aerosol-generating articles should be aligned parallel in a plane, and the same portion of each aerosol-generating article to be tested should be subjected to a specified load for a specified period of time. This test is conducted using a known DD60A densimetric device (manufactured and marketed by Heinr Borgwaldt Gmbh, Germany), equipped with a measuring head for aerosol-generating articles such as cigarettes and a container for the aerosol-generating article.

The load is applied using two cylindrical load application shafts that traverse the diameter of all aerosol-generating articles simultaneously. The standard test method for this measuring instrument specifies that the test should be conducted so that twenty points of contact are created between the aerosol-generating articles and the cylindrical load application shafts. In some cases, the hollow tubular segments being tested may be long enough that only ten aerosol-generating articles are required to create twenty points of contact, with each smoking article in contact with both load application shafts (because they are long enough to pass between the shafts). In other cases, if the support elements are too short to achieve this, twenty aerosol-generating articles should be used to create twenty points of contact, with each aerosol-generating article in contact with only one of the load application shafts, as discussed further below.

Two additional stationary cylindrical shafts are located below the aerosol generating articles to support the aerosol generating articles and to counteract the load applied by each of the cylindrical shafts to apply the load.

Under the standard operating conditions for such a device, a total load of 2 kg is applied for 20 seconds. After 20 seconds (and while the load continues to be applied to the smoking articles), the depression of the cylindrical shafts for applying the load is determined, and this value is then used to calculate the hardness according to the above equation. The temperature is maintained at approximately 22 degrees Celsius (2 degrees Celsius). The test described above is called the DD60A test. The standard method for measuring filter hardness is carried out when the aerosol-generating article is not consumed. Additional information on measuring average radial hardness can be found, for example, in published U.S. Patent Application Publication No. 2016/0128378.

When inserting an aerosol-generating article according to the present invention into an aerosol-generating device, the user may be required to apply some force to overcome the resistance of the aerosol-generating substrate and the aerosol-generating article to insertion. This may damage one or both of the aerosol-generating article and the aerosol-generating device. Furthermore, applying force when inserting the aerosol-generating article into the aerosol-generating device may displace the aerosol-generating substrate within the aerosol-generating article. This may result in improper alignment of the aerosol-generating device's heating element with the susceptor provided within the aerosol-generating substrate, which may lead to uneven and inefficient heating of the aerosol-generating substrate and the aerosol-generating article. The support element is preferably configured to resist movement of the aerosol-generating substrate further downstream during insertion of the article into the aerosol-generating device.

Preferably, the hollow tubular segment of the support element is adapted to generate an RTD of from about 0 millimeters of water (about 0 Pa) to about 20 millimeters of water (about 100 Pa), more preferably from about 0 millimeters of water (about 0 Pa) to about 10 millimeters of water (about 100 Pa). Therefore, the support element preferably does not contribute to the overall RTD of the aerosol-generating article.

In certain preferred embodiments, the downstream section of the aerosol generating article comprises a mouthpiece element located downstream of the aerosol generating element and in longitudinal alignment with the aerosol generating element.

The mouthpiece element is preferably located at the downstream end or mouthpiece end of the aerosol generating article and extends continuously to the mouthpiece end of the aerosol generating article.

The mouthpiece element preferably comprises at least one filter segment of a mouthpiece made of fibrous filter material for filtering the aerosol generated from the aerosol-generating substrate. Suitable fibrous filter materials are known to those skilled in the art. Particularly preferably, at least one filter segment of the mouthpiece comprises a cellulose acetate filter segment formed from cellulose acetate tow.

The mouthpiece element may consist of a single filtering mouthpiece segment. The mouthpiece element may comprise two or more filtering mouthpiece segments, coaxially aligned with one another and in end-to-end contact.

The downstream section may comprise a mouthpiece end cavity at the downstream end, downstream of the mouthpiece element, as described above. The mouthpiece end cavity may be defined by a hollow tubular element provided at the downstream end of the mouthpiece. The mouthpiece end cavity may be defined by an outer wrapper of the mouthpiece element, wherein the outer wrapper extends in a direction downstream of the mouthpiece element.

The mouthpiece may optionally contain a flavoring agent, which may be provided in any suitable form. For example, the mouthpiece may contain one or more capsules, beads, or granules of flavoring agent, or one or more threads or fibers filled with a flavoring agent.

In the aerosol generating article according to the present invention, the mouthpiece element forms part of a downstream section and is therefore located downstream of the aerosol generating element.

In certain preferred embodiments, the downstream section of the aerosol generating article further comprises both a support member located immediately downstream of the aerosol generating member and a mouthpiece member located downstream of the support member.

Preferably, the mouthpiece element has a low particle filtration efficiency.

Preferably, the mouthpiece is formed from a segment of fibrous filter material.

Preferably, the mouthpiece is surrounded by a wick. Preferably, the mouthpiece is not ventilated, so that air does not enter the aerosol-generating product along the mouthpiece.

The mouthpiece element is preferably connected to one or more adjacent upstream components of the aerosol generating article via a rim wrap.

Preferably, the mouthpiece element has an RTD of less than about 25 millimeters of water. More preferably, the mouthpiece element has an RTD of less than about 20 millimeters of water. Even more preferably, the mouthpiece element has an RTD of less than about 15 millimeters of water.

RTD values of from about 10 millimeters of water column to about 15 millimeters of water column are particularly preferred since a mouthpiece element having one such RTD value, which makes a minimal contribution to the overall RTD of the aerosol-generating article, is expected to have substantially no filtering effect on the aerosol delivered to the consumer.

The mouthpiece element preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol-generating article. The mouthpiece element may have an outer diameter of approximately 5 millimeters to approximately 10 millimeters, or approximately 6 millimeters to approximately 8 millimeters. In a preferred embodiment, the mouthpiece element has an outer diameter of approximately 7.2 millimeters.

The mouthpiece element preferably has a length of at least about 5 millimeters, more preferably at least about 8 millimeters, more preferably at least about 10 millimeters. The mouthpiece element preferably has a length of less than about 25 millimeters, more preferably less than about 20 millimeters, more preferably less than about 15 millimeters.

In some embodiments, the mouthpiece element preferably has a length of from about 5 millimeters to about 25 millimeters, more preferably from about 8 millimeters to about 25 millimeters, even more preferably from about 10 millimeters to about 25 millimeters. In other embodiments, the mouthpiece element preferably has a length of from about 5 millimeters to about 10 millimeters, more preferably from about 8 millimeters to about 20 millimeters, even more preferably from about 10 millimeters to about 20 millimeters. In further embodiments, the mouthpiece element preferably has a length of from about 5 millimeters to about 15 millimeters, more preferably from about 8 millimeters to about 15 millimeters, even more preferably from about 10 millimeters to about 15 millimeters.

For example, the mouthpiece element may have a length of approximately 5 millimeters to approximately 25 millimeters, or from approximately 8 millimeters to approximately 20 millimeters, or from approximately 10 millimeters to approximately 15 millimeters. In a preferred embodiment, the mouthpiece element has a length of approximately 12 millimeters.

In particularly preferred embodiments, the downstream section may further comprise an aerosol cooling element located downstream of the support element, wherein the mouthpiece element is located downstream of both the support element and the aerosol cooling element. Particularly preferably, the mouthpiece element is located directly downstream of the aerosol cooling element. As an example, the mouthpiece element may be adjacent to the downstream end of the aerosol cooling element.

The aerosol cooling element may, for example, define a plurality of longitudinally extending channels in such a way as to provide a large surface area for heat exchange. The plurality of longitudinally extending channels may be defined by a sheet material that has been pleated, gathered, or folded to form channels. The plurality of longitudinally extending channels may be defined by a single sheet that has been pleated, gathered, or folded to form multiple channels. The sheet may also be corrugated before being pleated, gathered, or folded. Alternatively, the plurality of longitudinally extending channels may be defined by multiple sheets that have been corrugated, pleated, gathered, or folded to form multiple channels. In some embodiments, the plurality of longitudinally extending channels may be defined by multiple sheets that have been corrugated, pleated, gathered, or folded together, that is, two or more sheets that are introduced into an overlapping arrangement and then corrugated, pleated, gathered, or folded as a single sheet.

One such aerosol cooling element may have a total surface area from approximately 300 square millimeters per millimeter of length to approximately 1000 square millimeters per millimeter of length.

One such aerosol cooling element preferably provides low resistance to the passage of air through the additional cooling element. Preferably, the aerosol cooling element does not substantially affect the draw resistance of the aerosol-generating article. The aerosol cooling element preferably comprises a sheet material selected from the group consisting of a metal foil, a sheet of a polymeric material, and substantially non-porous paper or cardboard. In some embodiments, the aerosol cooling element may comprise a sheet material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose acetate (CA), and aluminum foil. In a particularly preferred embodiment, the additional cooling element comprises a PLA sheet.

The aerosol-generating article may further comprise an upstream section at a location upstream of the aerosol-generating element. The upstream section may comprise one or more upstream elements. In some embodiments, the upstream section may comprise an upstream element located immediately upstream of the aerosol-generating element.

The aerosol-generating article of the present invention preferably comprises an upstream element located upstream of and adjacent to the aerosol-generating element, wherein the upstream section comprises at least one upstream element. The upstream element advantageously prevents direct physical contact with the upstream end of the aerosol-generating substrate. In particular, the upstream element can prevent direct physical contact with the upstream end of the susceptor element located within the aerosol-generating element. This helps prevent displacement or deformation of the susceptor element during processing or transportation of the aerosol-generating article. This, in turn, helps maintain the shape and position of the susceptor element. In addition, the presence of the upstream element helps prevent any loss of substrate.

The upstream element may also provide an enhanced appearance to the upstream end of the aerosol-generating article. Furthermore, if desired, the upstream element may be used to provide information about the aerosol-generating article, such as brand, flavor, content, or information about the aerosol-generating device with which the article is intended.

The upstream element may be a porous rod-shaped element. Preferably, the porous rod-shaped element does not change the draw resistance of the aerosol-generating article. Preferably, the upstream element has a porosity of at least approximately 50 percent in the longitudinal direction of the aerosol-generating article. More preferably, the upstream element has a porosity of from approximately 50 percent to approximately 90 percent in the longitudinal direction. The porosity of the upstream element in the longitudinal direction is determined by the ratio of the cross-sectional area of the material forming the upstream element and the internal cross-sectional area of the aerosol-generating article at the position of the upstream element.

The upstream element may be made of a porous material or may contain multiple holes. This can be achieved, for example, by laser perforation. Preferably, the multiple holes are uniformly distributed across the cross-section of the upstream element.

The porosity or permeability of the upstream element can advantageously be varied to provide the desired overall draw resistance of the aerosol generating article.

Preferably, the RTD of the upstream element is at least about 5 millimeters of water column. More preferably, the RTD of the upstream element is at least about 10 millimeters of water column. Even more preferably, the RTD of the upstream element is at least about 15 millimeters of water column. In particularly preferred embodiments, the RTD of the upstream element is at least about 20 millimeters of water column.

The RTD of the upstream element is preferably less than or equal to about 80 millimeters of water. More preferably, the RTD of the upstream element is less than or equal to about 60 millimeters of water. Even more preferably, the RTD of the upstream element is less than or equal to about 40 millimeters of water.

In some embodiments, the RTD of the upstream element is from about 5 millimeters of water to about 80 millimeters of water, preferably from about 10 millimeters of water to about 80 millimeters of water, more preferably from about 15 millimeters of water to about 80 millimeters of water, even more preferably from about 20 millimeters of water to about 80 millimeters of water. In other embodiments, the RTD of the upstream element is from about 5 millimeters of water to about 60 millimeters of water, preferably from about 10 millimeters of water to about 60 millimeters of water, more preferably from about 15 millimeters of water to about 60 millimeters of water, even more preferably from about 20 millimeters of water. to about 60 millimeters of water column. In further embodiments, the RTD of the upstream element is from about 5 millimeters of water column to about 40 millimeters of water column, preferably from about 10 millimeters of water column to about 40 millimeters of water column, more preferably from about 15 millimeters of water column to about 40 millimeters of water column, even more preferably from about 20 millimeters of water column to about 40 millimeters of water column.

The upstream element can be formed from an air-impermeable material. The aerosol-generating article can be designed so that air flows into the aerosol-generating substrate core through suitable ventilation means provided in the wrapper.

The upstream element may be made of any material suitable for use in an aerosol-generating article. The upstream element may be made, for example, of the same material used for one of the other components of the aerosol-generating article, such as a mouthpiece, a cooling element, or a support element. Suitable materials for forming the upstream element include filter materials, ceramics, polymeric material, cellulose acetate, cardboard, zeolite, or an aerosol-generating substrate. Preferably, the upstream element is formed from a cellulose acetate rod.

Preferably, the upstream element is made of a heat-resistant material. For example, the upstream element is preferably made of a material that can withstand temperatures up to 350 degrees Celsius. This ensures that the upstream element is not adversely affected by the heating means used to heat the aerosol-generating substrate.

Preferably, the upstream element has a diameter that is approximately equal to the diameter of the aerosol generating article.

Preferably, the upstream element has a length of from about 1 millimeter to about 10 millimeters, more preferably from about 3 millimeters to about 8 millimeters, more preferably from about 4 millimeters to about 6 millimeters. In a particularly preferred embodiment, the upstream element has a length of about 5 millimeters. The length of the upstream element can advantageously be varied to provide the desired overall length of the aerosol-generating article. For example, if it is desired to reduce the length of one of the other components of the aerosol-generating article, the length of the upstream element can be increased to maintain the overall length of the article at the same level.

The upstream element preferably has a substantially uniform structure. For example, the upstream element may have a substantially uniform texture and appearance. The upstream element may, for example, have a continuous, flat surface across its entire cross-section. The upstream element may, for example, have no recognizable symmetries.

The upstream element is preferably surrounded by a wrapper. The wrapper surrounding the upstream element is preferably a rigid filament, for example a filament having a basis weight of at least about 80 grams per square meter (g/ ^m2 ), or at least about 100 g/ ^m2 , or at least about 110 g/ ^m2 . This provides structural rigidity to the upstream element.

The aerosol generating article may have a length ranging from approximately 35 millimeters to approximately 100 millimeters.

The aerosol generating article may have a length ranging from approximately 35 millimeters to approximately 100 millimeters.

Preferably, the overall length of the aerosol-generating article according to the present invention is at least about 38 millimeters. More preferably, the overall length of the aerosol-generating article according to the present invention is at least about 40 millimeters. Even more preferably, the overall length of the aerosol-generating article according to the present invention is at least about 42 millimeters.

The overall length of the aerosol-generating article according to the present invention is preferably less than or equal to 70 millimeters. More preferably, the overall length of the aerosol-generating article according to the present invention is preferably less than or equal to 60 millimeters. Even more preferably, the overall length of the aerosol-generating article according to the present invention is preferably less than or equal to 50 millimeters.

In some embodiments, the overall length of the aerosol-generating article is preferably from about 38 millimeters to about 70 millimeters, more preferably from about 40 millimeters to about 70 millimeters, even more preferably from about 42 millimeters to about 70 millimeters. In other embodiments, the overall length of the aerosol-generating article is preferably from about 38 millimeters to about 60 millimeters, more preferably from about 40 millimeters to about 60 millimeters, even more preferably from about 42 millimeters to about 60 millimeters. In further embodiments, the overall length of the aerosol-generating article is preferably from about 38 millimeters to about 50 millimeters, more preferably from about 40 millimeters to about 50 millimeters, even more preferably from about 42 millimeters to about 50 millimeters. In an exemplary embodiment, the overall length of the aerosol generating article is approximately 45 millimeters.

The aerosol-generating article has an outer diameter of at least 5 millimeters. Preferably, the aerosol-generating article has an outer diameter of at least 6 millimeters. More preferably, the aerosol-generating article has an outer diameter of at least 7 millimeters.

Preferably, the aerosol-generating article has an outer diameter of less than or equal to approximately 12 millimeters. More preferably, the aerosol-generating article has an outer diameter of less than or equal to approximately 10 millimeters. Even more preferably, the aerosol-generating article has an outer diameter of less than or equal to approximately 8 millimeters.

In some embodiments, the aerosol-generating article has an outer diameter of about 5 millimeters to about 12 millimeters, preferably about 6 millimeters to about 12 millimeters, more preferably about 7 millimeters to about 12 millimeters. In other embodiments, the aerosol-generating article has an outer diameter of about 5 millimeters to about 10 millimeters, preferably about 6 millimeters to about 10 millimeters, more preferably about 7 millimeters to about 10 millimeters. In further embodiments, the aerosol-generating article has an outer diameter of about 5 millimeters to about 8 millimeters, preferably about 6 millimeters to about 8 millimeters, more preferably about 7 millimeters to about 8 millimeters.

Preferably, the aerosol generating article according to the present invention comprises, in a linear sequential arrangement, an upstream element, an aerosol generating element located immediately downstream of the upstream element, a support element located immediately downstream of the aerosol generating element, a mouthpiece element located immediately downstream of the support element, and an outer wrapper surrounding the upstream element, the aerosol generating element, the support element and the mouthpiece element.

In more detail, the aerosol-generating element may be adjacent to an upstream element. The support element may be adjacent to the aerosol-generating element. The aerosol-cooling element may be adjacent to the support element. The mouthpiece element may be adjacent to the aerosol-cooling element.

The aerosol generating article has a substantially cylindrical shape and an outer diameter of approximately 7.25 millimeters.

The upstream element is approximately 5 millimeters long, the aerosol-generating element is approximately 12 millimeters long, the support element is approximately 16 millimeters long, and the mouthpiece element is approximately 12 millimeters long. Thus, the total length of the aerosol-generating article is approximately 45 millimeters.

The upstream element is in the form of a cellulose acetate rod wrapped in a rigid fibreglass.

The aerosol-generating article comprises an elongated current collector located substantially longitudinally within the aerosol-generating substrate and thermally bonded to the aerosol-generating substrate. The current collector is shaped like a strip or plate, has a length substantially equal to the length of the aerosol-generating element, and a thickness of approximately 60 micrometers.

The support element is shaped like a hollow acetate cellulose tube and has an internal diameter of approximately 1.9 millimeters. Therefore, the thickness of the peripheral wall of the support element is approximately 2.675 millimeters.

The mouthpiece is shaped as a filter segment made of low density cellulose acetate.

The aerosol-generating substrate contains homogenized tobacco.

The coating composition coats a major portion of the outer surface of the current collector, preferably substantially the entire outer surface of the current collector.

As briefly mentioned above, the aerosol generating articles according to the present invention can be manufactured at high speed by applying suitable methods on existing equipment without the need for significant modification thereof.

In one such method, the first step involves providing an aerosol-generating substrate containing homogenized tobacco material containing an aerosol-forming substance. The second step involves providing a protected coated current collector, wherein the protected coated current collector comprises a current collector element coated with a coating composition containing an aerosol-forming substance and isolated nicotine and/or a monobasic nicotine salt, and a protective layer applied over the coating composition. The third step involves removing the protective layer to expose the coating composition and provide an unprotected coated current collector. The fourth step involves combining the unprotected coated current collector and the aerosol-generating substrate to form an aerosol-generating element, such that the unprotected coated current collector is located within the aerosol-generating element and is configured to heat the homogenized tobacco material in the aerosol-generating substrate.

According to this method, the coated current collector can be advantageously stored in a protected state, effectively preserving the coating composition. Since the protective layer can only be removed immediately before combining the coated current collector with the aerosol-generating substrate to form the aerosol-generating element, the coating composition is advantageously protected, for example, during storage or transport, from dust or other potential contaminants. Furthermore, the presence of such a protective layer can prevent the layers of the coated current collector from adhering to each other if, for example, the coated current collector is supplied wound onto a reel. The protective layer can be, for example, in the form of a metal foil, such as aluminum foil, and can be removed mechanically. In one embodiment, a continuous strip of the protected coated current collector can be fed through a foil removal unit, where the protective layer is removed, for example, using wedges, and wound off. A continuous strip of coated susceptor exiting the foil stripper may be fed into a cone or funnel along with a sheet of homogenized tobacco material and a sheet of wrapper material to combine into a continuous rod, which may subsequently be cut into segments of a given length.

In another suitable method, the first step comprises providing an aerosol-generating substrate comprising homogenized tobacco material containing an aerosol-forming agent. The second step comprises providing a current-collecting element. The third step comprises coating the current-collecting element with a coating composition comprising the aerosol-forming agent and isolated nicotine and/or a monobasic nicotine salt to form a coated current-collecting element. The fourth step comprises combining the coated current-collecting element and the aerosol-generating substrate to form an aerosol-generating element, such that the coated current-collecting element is positioned within the aerosol-generating element and is configured to heat the homogenized tobacco material.

According to this method, the coating composition can be applied to the outer surface of the current-collecting element in the same rooms where the coated current-collecting element and the aerosol-generating substrate are combined. This can be achieved by applying the coating composition to a metal strip forming the current-collecting element. The coated current-collecting element thus formed can be fed into a cone or funnel along with a sheet of homogenized tobacco material and a sheet of wrapper material to create a continuous rod preform, which can then be cut into segments of a predetermined length.

The present invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

Example 1. An aerosol-generating article for producing an inhalable aerosol upon heating, wherein the aerosol-generating article comprises: an aerosol-generating element comprising an aerosol-generating substrate, wherein the aerosol-generating substrate comprises homogenized tobacco material comprising an aerosol-forming substance; and a current collector located within the aerosol-generating element and configured to heat the homogenized tobacco material, wherein the current collector is coated with a coating composition comprising at least 20 percent by weight of an aerosol-forming substance, wherein the coating composition further comprises isolated nicotine and/or a monobasic salt of nicotine.

Example 2. An aerosol generating article according to example 1, wherein the current collector is surrounded by homogenized tobacco material.

Example 3. An aerosol generating article according to example 1 or 2, wherein the current collector is an elongated current collector and extends in the longitudinal direction within the aerosol generating element.

Example 4. An aerosol generating article according to any of examples 1-3, wherein the homogenized tobacco material is provided in the form of an assembled sheet of homogenized tobacco material.

Example 5. An aerosol-generating article according to any of the previous examples, wherein the coating composition comprises at least one gelling agent that forms a solid medium, wherein the aerosol-forming substance is distributed in the solid medium, wherein the isolated nicotine and/or monobasic nicotine salt are distributed in the aerosol-forming substance.

Example 6. An aerosol generating article according to example 5, wherein the gelling agent comprises carboxymethylcellulose (CMC) and/or hydroxypropylmethylcellulose (HPMC), and the aerosol forming substance comprises glycerin.

Example 7. An aerosol-generating article according to any of the previous examples, wherein the aerosol-forming substance comprises at least about 50 percent by weight of the coating composition.

Example 8. An aerosol-generating article according to any of the previous examples, wherein the isolated nicotine and/or nicotine salt comprises at least about 0.5 percent by weight of the coating composition.

Example 9. An aerosol generating article according to any of the previous examples, wherein the coating composition forms a layer on the outer surface of the current collector, wherein the thickness of the layer is at least about 1 micrometer.

Example 10. An aerosol-generating article according to any of the previous examples, wherein the content of the aerosol-forming substance in the coating composition is at least about 0.25 percent of the total content of the aerosol-forming substance in the aerosol-generating article.

Example 11. An aerosol generating article according to any of the previous examples, comprising a downstream section at a location downstream of the aerosol generating element, wherein the downstream section comprises a support element located immediately downstream of the aerosol generating element, wherein the support element is in longitudinal alignment with the aerosol generating element and comprises a hollow tubular segment.

Example 12. An aerosol generating article according to example 11, comprising a mouthpiece element at a location downstream of the support element.

Example 13. An aerosol-generating article according to any of the previous examples, comprising an upstream section at a location upstream of the aerosol-generating element, wherein the upstream section comprises an upstream element located immediately upstream of the aerosol-generating element and having a resistance to draw (RTD) of less than about 80 millimeters of water.

Example 14. A method of manufacturing an aerosol-generating article for generating an inhalable aerosol upon heating, the method comprising: providing an aerosol-generating substrate comprising homogenized tobacco material comprising an aerosol-forming agent; providing a protected coated susceptor, wherein the protected coated susceptor comprises a susceptor element coated with a coating composition comprising an aerosol-forming agent and isolated nicotine and/or a monobasic nicotine salt, and a protective layer applied to the coating composition; removing the protective layer to expose the coating composition and provide an unprotected coated susceptor; combining the unprotected coated susceptor and the aerosol-generating substrate to form an aerosol-generating element, such that the unprotected coated susceptor is located within the aerosol-generating element and is configured to heat the homogenized tobacco material.

Example 15. A method of manufacturing an aerosol-generating article for generating an inhalable aerosol upon heating, the method comprising: providing an aerosol-generating substrate comprising homogenized tobacco material comprising an aerosol-forming agent; providing a current-collecting element; coating the current-collecting element with a coating composition comprising an aerosol-forming agent and isolated nicotine and/or a monobasic nicotine salt to provide a coated current-collecting element; combining the coated current-collecting element and the aerosol-generating substrate to form an aerosol-generating element, such that the coated current-collecting element is located within the aerosol-generating element and is configured to heat the homogenized tobacco material.

The present invention will now be further described with reference to the drawings, in which:

Fig. 1 shows qualitatively how the aerosol delivery changes over time during use of an aerosol generating article in accordance with the present invention;

Fig. 2 shows a schematic side sectional view of an aerosol generating article in accordance with the present invention; and

Fig. 3 is a schematic perspective view of a coated current collector for use in an aerosol generating article in accordance with the present invention.

The aerosol-generating article 10 shown in Fig. 2 comprises an aerosol-generating element 12 that contains an aerosol-generating substrate and a downstream section 14 at a location downstream of the aerosol-generating element 12. Furthermore, the aerosol-generating article 10 comprises an upstream section 16 at a location upstream of the aerosol-generating element 12. Thus, the aerosol-generating article 10 extends from an upstream or distal end 18 to a downstream or mouthpiece end 20.

The aerosol generating product has an overall length of approximately 45 millimetres.

The downstream section 14 comprises a support element 22 located immediately downstream of the aerosol generating element 12, wherein the support element 22 is in longitudinal alignment with the aerosol generating element 12. In the embodiment of Fig. 2, the upstream end of the support element 18 is adjacent to the downstream end of the aerosol generating element 12.

The support member 22 comprises a hollow tubular segment 24. The hollow tubular segment 24 is in the form of a hollow cylindrical tube made of cellulose acetate. The hollow tubular segment 24 defines an internal cavity 26 that extends continuously from the upstream end 30 of the hollow tubular segment to the downstream end 32 of the hollow tubular segment 20. The internal cavity 26 is substantially empty, and therefore, a substantially unimpeded air flow is provided through the internal cavity 26. The hollow tubular segment 24, and, as a consequence, the support member 22, does not make a significant contribution to the overall RTD of the aerosol-generating article 10. In more detail, the RTD of the first hollow tubular segment 24 (which is essentially the RTD of the support member 22) is substantially 0 millimeters of water.

The hollow tubular segment 24 has a length of approximately 16 millimeters, an outer diameter of approximately 7.25 millimeters, and an inner diameter of approximately 1.9 millimeters. Thus, the thickness of the peripheral wall of the first hollow tubular segment 26 is approximately 2.67 millimeters.

In the embodiment of Fig. 2, the downstream section 14 further comprises a mouthpiece element 42 at a location downstream of the support element 22. In more detail, the mouthpiece element 42 is located immediately downstream of the support element 22. As shown in the image of Fig. 2, the upstream end of the mouthpiece element 4 2 adjoins the downstream end 4 0 of the support element 22.

The mouthpiece element 42 is provided in the form of a cylindrical rod made of low density cellulose acetate.

The mouthpiece element 42 has a length of approximately 12 millimeters and an outer diameter of approximately 7.25 millimeters. The RTD of the mouthpiece element 42 is approximately 12 millimeters of water.

The aerosol generating element 12 comprises a sheet of homogenized tobacco material assembled to form a rod having an outer diameter of approximately 7.25 millimeters and a length of approximately 12 millimeters.

The aerosol-generating article 10 further comprises an elongated current collector 44 within the aerosol-generating substrate 12. In more detail, the current collector 44 is positioned substantially longitudinally within the aerosol-generating substrate in such a way as to be approximately parallel to the longitudinal direction of the aerosol-generating element 12. As shown in the image of Fig. 2, the current collector 44 is positioned in a radially central position within the rod and extends substantially along the longitudinal axis of the aerosol-generating element 12.

The current collector 44 extends continuously from the upstream end to the downstream end of the aerosol-generating element 12. In fact, the current collector 44 has substantially the same length as the aerosol-generating element.

In the embodiment of Fig. 2, the current collector 44 is provided in the form of a metal strip and has a length of approximately 12 millimeters, a thickness of approximately 60 micrometers and a width of approximately 4 millimeters.

The upstream section 16 comprises an upstream element 46 located immediately upstream of the aerosol generating element 12, wherein the upstream element 46 is in longitudinal alignment with the aerosol generating element 12. In the embodiment of Fig. 1, the downstream end of the upstream element 46 abuts the upstream end of the aerosol generating element 12. This advantageously prevents the current collector 44 from shifting. In addition, this ensures that the consumer cannot accidentally touch the heated current collector 44 after use.

Upstream element 46 is in the form of a cylindrical rod of cellulose acetate surrounded by a rigid wrapper. Upstream element 46 has a length of approximately 5 millimeters. The RTD of upstream element 46 is approximately 30 millimeters of water column.

The current collector 44 is shown in more detail in Fig. 3. The outer surface of the metal strip is coated with a layer 48 of the coating composition, the thickness of the layer 48 is approximately 30 micrometers.

An example of a suitable coating composition is shown below in Table 1.

As shown in Fig. 3, both the upper side 50 and the lower side 52 of the strip of the current collector 44 are covered with a corresponding layer 54, 56 containing a coating composition. In addition, Fig. 3 shows how, in accordance with one of the manufacturing methods described above, the current collector 44 can be provided with protective layers 58, 60 applied over the layers 54, 56 containing the coating composition.

For the purposes of this description and the appended claims, except where otherwise indicated, all numbers expressing quantities, amounts, percentages, etc., are to be understood as modified in all instances by the term "about." Also, all ranges include the disclosed maximum and minimum points and include any intermediate ranges therebetween, which may or may not be specifically listed herein. Therefore, in this context, the number A is understood as A (10% of A. In this context, the number A may be considered to include numerical values that are within the normal standard error for measuring the property that the number A modifies. The number A, in some cases, when used in the appended claims, may deviate by the percentages listed above, provided that the amount by which A deviates does not significantly affect the fundamental and novel characteristic(s) of the claimed invention. Also, all ranges include the disclosed maximum and minimum points and include any intermediate ranges therebetween that may or may not be specifically listed herein.

Claims (24)

1. An aerosol-generating article for producing an inhalable aerosol upon heating, wherein the aerosol-generating article comprises: an aerosol generating element and comprising an aerosol generating substrate, wherein the aerosol generating substrate comprises homogenized tobacco material comprising an aerosol forming substance; and a current collector located within the aerosol generating element and configured to heat the homogenized tobacco material, wherein the current collector is coated with a coating composition containing at least 20% by weight of an aerosol forming substance, and the coating composition further contains from 0.5 to 10% by weight of isolated nicotine and/or a monobasic nicotine salt obtained from tobacco. 2. An aerosol generating article according to claim 1, wherein the current collector is surrounded by homogenized tobacco material. 3. An aerosol generating article according to claim 1 or 2, wherein the current collector is an elongated current collector and extends in a longitudinal direction within the aerosol generating element. 4. An aerosol generating article according to any one of paragraphs 1-3, wherein the homogenized tobacco material is in the form of an assembled sheet of homogenized tobacco material. 5. An aerosol-generating article according to any one of the preceding claims, wherein the coating composition comprises at least one gelling agent that forms a solid medium, wherein the aerosol-forming substance is distributed in the solid medium, and wherein the released nicotine and/or monobasic nicotine salt are distributed in the aerosol-forming substance. 6. An aerosol generating article according to claim 5, wherein the gelling agent comprises carboxymethylcellulose (CMC) and/or hydroxypropylmethylcellulose (HPMC) and the aerosol forming agent comprises glycerin. 7. An aerosol-generating article according to any one of the preceding claims, wherein the aerosol-forming substance constitutes at least 50% by weight of the coating composition. 8. An aerosol generating article according to any one of the preceding claims, wherein the coating composition forms a layer on the outer surface of the current collector, the thickness of the layer being at least 1 µm. 9. An aerosol-generating article according to any one of the preceding claims, wherein the content of the aerosol-forming substance in the coating composition is at least 0.25% of the total content of the aerosol-forming substance in the aerosol-generating article. 10. An aerosol generating article according to any one of the preceding claims, comprising a downstream section at a location downstream of the aerosol generating element, wherein the downstream section comprises a support member located immediately downstream of the aerosol generating element, and the support member is in longitudinal alignment with the aerosol generating element, and comprises a hollow tubular segment. 11. An aerosol generating article according to claim 10, comprising a mouthpiece element at a location located further downstream of the support element. 12. An aerosol-generating article according to any one of the preceding claims, comprising an upstream section at a location upstream of the aerosol-generating element, wherein the upstream section comprises an upstream element located immediately upstream of the aerosol-generating element and having a resistance to draw (RTD) of less than 80 mm H2O. 13. A method for manufacturing an aerosol generating article for generating an inhalable aerosol upon heating, the method comprising: providing an aerosol-generating substrate containing homogenized tobacco material containing an aerosol-forming agent; providing a protected coated current collector, wherein the protected coated current collector comprises a current collector element coated with a coating composition comprising an aerosol forming agent and from 0.5 to 10% by weight of isolated nicotine and/or a monobasic nicotine salt obtained from tobacco, and a protective layer applied to the coating composition; removing the protective layer to expose the coating composition and provide an unprotected coated current collector; combining an unprotected coated current collector and an aerosol generating substrate to form an aerosol generating element, such that the unprotected coated current collector is located within the aerosol generating element and is configured to heat the homogenized tobacco material. 14. A method for manufacturing an aerosol generating article for generating an inhalable aerosol upon heating, the method comprising: providing an aerosol-generating substrate containing homogenized tobacco material containing an aerosol-forming agent; providing a current-collecting element; coating the current collecting element with a coating composition comprising an aerosol forming agent and from 0.5 to 10% by weight of isolated nicotine and/or a monobasic nicotine salt obtained from tobacco to provide a coated current collecting element; combining a coated current collector and an aerosol generating substrate to form an aerosol generating element, such that the coated current collector is located within the aerosol generating element and is configured to heat the homogenized tobacco material.