Stable wrapper for aerosol-generating articles

Abstract

A wrapper for use on a smoking article. The wrapper has low grease permeability or visual staining and can be utilized with an aerosol-generating substrate. The aerosol-generating article (10) includes an aerosol-generating substrate (12) containing nicotine and a gel composition. The wrapper is positioned around and in contact with the aerosol-generating substrate. The wrapper includes a paper layer (50) that includes a surface treatment such that the paper has a negative result to at least one kit oil sample according to Method Tappi 559cm-02, Classical Method 2002.

Description

Technical Field

[0001] The present disclosure relates to wrappers used in smoking articles, which have low grease permeability or visual staining and can be used with an aerosol-generating substrate.

Background Art

[0002] Aerosol-generating articles in which an aerosol-generating substrate such as a tobacco-containing substrate is heated rather than burned are well known in the art. Typically, in such heated aerosol-generating articles, the aerosol is generated by transferring heat from a heat source to a physically separated aerosol-generating substrate or material, which may be in contact with the heat source, within the heat source, around the heat source, or downstream of the heat source. During use of the aerosol-generating article, volatile compounds are released from the aerosol-generating substrate by heat transfer from the heat source and entrained in the air drawn through the aerosol-generating article. The released compounds condense as they cool to form an aerosol.

[0003] The paper used to wrap the aerosol-generating substrate can absorb aerosol formers, water, and other liquid compounds in the mainstream smoke or aerosol passing through the aerosol-generating article, or moisture or water around the paper. The absorbed liquid can stain or weaken the paper, negatively affecting the appearance and structural integrity of the aerosol-generating article. Heated aerosol-generating articles are particularly susceptible to the effects of wetting and damage due to the high levels of aerosol formers in the aerosol-generating substrates of these heated aerosol-generating articles. Heated aerosol-generating articles are particularly prone to expansion because aerosol components are absorbed by the wrapper, making removal from the heating device difficult. Heated aerosol-generating articles are particularly prone to breakage when firmly housed and then removed from the heating device.

[0004] For aerosol-generating articles containing particularly high levels of liquid or aerosol-forming substances, it is desirable to provide a visually and mechanically stable, enclosed aerosol-generating substrate.

[0005] It is desirable to provide an aerosol-generating article comprising a wrapper that does not expand by absorbing water or compounds contained in the aerosol-generating substrate.

[0006] It is desirable to provide an aerosol-generating article comprising a wrapper that provides a grease barrier against grease compounds contained in the aerosol-generating substrate. SUMMARY OF THE INVENTION

[0007] Also, it is desirable that the wrapper does not affect the taste of the aerosol generated by the aerosol-generating article.

[0008] Also, it is desirable that the wrapper does not readily burn when in proximity to the heating element.

[0009] The object of the present invention may be to at least partially solve one or more of the above desirable technical advantages.

[0010] According to the present disclosure, there is provided an aerosol-generating article comprising an aerosol-generating substrate comprising nicotine and a wrapper disposed around the aerosol-generating substrate. The wrapper comprises a paper layer having a negative result for at least one kit oil sample of method Tappi 559cm-02, classical method 2002.

[0011] According to the present disclosure, there is provided an aerosol-generating article comprising an aerosol-generating substrate comprising nicotine and a gel composition and a wrapper disposed around and in contact with the aerosol-generating substrate. The wrapper comprises a paper layer comprising a surface treatment such that the paper has a negative result for at least one kit oil sample of method Tappi 559cm-02, classical method 2002.

[0012] According to the present disclosure, an aerosol-generating article is provided. The aerosol-generating article may comprise an aerosol-generating substrate. The aerosol-generating substrate may include a wrapper. The wrapper may be disposed around the aerosol-generating substrate. The wrapper includes a paper layer having a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002.

[0013] Preferably, the paper layer has a negative result for at least five kit oil samples of Method Tappi 559cm-02, Classical Method 2002. Preferably, the paper layer has a negative result for at least eight kit oil samples of Method Tappi 559cm-02, Classical Method 2002. Preferably, the paper layer has a negative result for all ten kit oil samples of Method Tappi 559cm-02, Classical Method 2002.

[0014] Preferably, the paper layer has a thickness / grammage in the range of about 1.0 micrometers / gsm to about 1.2 micrometers / gsm. The paper layer may have a thickness of less than about 50 micrometers, or less than about 40 micrometers. The wrapper includes a paper layer having a grammage in the range of about 25 gsm to about 45 gsm, or about 35 gsm to about 40 gsm. Preferably, the paper layer has a grammage in the range of about 25 gsm to about 45 gsm and a thickness in the range of about 35 micrometers to about 50 micrometers.

[0015] Preferably, the paper layer has a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002 and a water contact angle of at least 30 degrees. The paper layer may have a water contact angle of at least about 40 degrees, or at least about 45 degrees.

[0016] The wrapper preferably includes a paper layer having a breaking elongation CD / MD of about 2.5 or less and having a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002. The paper layer may have a negative result for at least five kit oil samples, or all ten kit oil samples, of Method Tappi 559cm-02, Classical Method 2002.

[0017] The wrapper preferably includes two paper layers. The first paper layer has a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002, and the second paper layer has a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002. The wrapper may have a total thickness of less than about 80 micrometers.

[0018] The wrapper preferably includes PVOH (polyvinyl alcohol) or silicon. The paper layer may include a surface treatment including PVOH or silicon. The addition of PVOH (polyvinyl alcohol) or silicon may improve the grease barrier properties of the wrapper.

[0019] The term "silicon" refers to siloxane. The silicon or siloxane preferably includes polydimethylsiloxane.

[0020] The aerosol generating substrate preferably may include a homogenized tobacco material. The tobacco homogenized tobacco material may include, on a dry mass basis, about 1% to about 5% binder and about 5% to about 30% aerosol former tobacco material.

[0021] The aerosol generating substrate preferably may include a gel composition. The gel composition may include a majority (by weight) of glycerin. The gel composition may include xanthan gum.

[0022] The aerosol generation substrate preferably may include a metal induction heating element. The metal induction heating element may include a plurality of metal induction heating elements. The metal induction heating element may include one metal induction heating element.

[0023] The wrapper may be formed from one layer of paper. The wrapper may be formed from two layers of paper. The wrapper may be formed from two or more layers of paper.

[0024] The wrapper preferably covers at least 20%, at least 50%, at least 80%, at least 90%, at least 95%, at least 99%, or preferably substantially the entire length of the aerosol generation substrate. The wrapper preferably covers the entire aerosol generation substrate and does not extend beyond the aerosol generation substrate.

[0025] When the wrapper has two or more paper layers, the first paper layer may have the unique properties described herein, and the second paper layer may be regarded as a conventional paper layer. The second paper layer may preferably be disposed on top of the first paper layer. Alternatively, the first paper layer may be disposed on top of the second paper layer. The first paper layer having the unique properties described herein preferably is in contact with the aerosol formation substrate.

[0026] When the wrapper has two or more paper layers, the first paper layer may have the unique properties described herein, and the second paper layer may also have the unique properties described herein. All paper layers forming the wrapper may have the unique properties described herein. In particular, one or both of the paper layers forming the wrapper may contain PVOH (polyvinyl alcohol) or silicon. One or both of the paper layers forming the wrapper may include a surface treatment containing PVOH or silicon. Advantageously, a smoking article or an aerosol-generating article containing the paper wrapper described herein may reduce the wetting and absorption of water, wetting agents, or greases in the smoke or aerosol passing through the smoking article or aerosol-generating article. As a result, even when a high level of wetting agent is contained in the aerosol-generating substrate, visible soiling and physical weakening of the wrapper portion of the smoking article or aerosol-generating article may be reduced.

[0027] Paper wrappers having a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002 show a decrease in paper swelling. Paper wrappers having a negative result for at least five kit oil samples of Method Tappi 559cm-02, Classical Method 2002 preferably show a decrease in paper swelling. Paper wrappers having a negative result for all ten kit oil samples of Method Tappi 559cm-02, Classical Method 2002 preferably show a decrease in paper swelling.

[0028] Advantageously, an aerosol-generating article containing the wrapper described herein may reduce the absorption of moisture, water, aerosol former, or grease in the smoke or aerosol passing through the aerosol-generating article. As a result, even when a high level of aerosol former is contained in the aerosol-generating substrate, swelling, visible soiling, and physical weakening of the wrapper portion of the aerosol-generating article may be reduced.

[0029] Advantageously, the aerosol-generating article provides a visually and mechanically stable, encapsulated aerosol-generating substrate that avoids expansion. This is particularly useful for heat-not-burn aerosol-generating articles that can be inserted into a heating device. The aerosol-generating article wrapper is resistant to combustion when in proximity to the heating element, so the induction heating element can be incorporated throughout the aerosol-generating substrate.

[0030] The term "aerosol-generating article" is used herein to mean an article in which an aerosol-generating substrate is heated to generate an inhalable aerosol and deliver it to a consumer. The term "aerosol-generating substrate" as used herein means a substrate having the ability to release volatile compounds upon heating to generate an aerosol.

[0031] Conventional cigarettes are 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 the oxygen in the air drawn through the cigarette ignites the end of the cigarette, and the resulting combustion generates inhalable smoke. In contrast, in a heated aerosol-generating article, 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 the transfer of heat from a combustible fuel element or heat source to an aerosol-forming substrate physically separated therefrom. For example, the aerosol-generating article according to the present disclosure has a specific use in an aerosol-generating system comprising an electrically heated aerosol-generating device having an internal heater blade adapted to be inserted into a rod of the aerosol-generating substrate. This type of aerosol-generating article is described in the prior art, for example, in EP0822670.

[0032] The term "aerosol-generating device" as used herein refers to a device comprising a heater element that interacts with the aerosol-generating substrate of the aerosol-generating article to generate an aerosol.

[0033] As used herein, the term "aerosol generating system" means a combination of an aerosol generating device and an aerosol generating article.

[0034] The term "aerosol generating substrate" refers to a substance capable of generating or releasing an aerosol. The aerosol generating substrate may be a solid, paste, gel, slurry, liquid, or may include any combination of solid, paste, gel, slurry, and liquid compounds. The aerosol generating substrate is preferably a solid or gel composition. The aerosol generating substrate preferably contains nicotine.

[0035] The aerosol generating article may comprise an aerosol generating substrate and a mouthpiece. The mouthpiece may include a filter. The tipping wrapper may bind the filter to the aerosol generating substrate.

[0036] The aerosol generating substrate may be a solid composition. This composition may include plant-based materials. The aerosol generating substrate may include tobacco, and the tobacco preferably contains volatile tobacco flavor compounds released from the aerosol generating substrate in response to heating. The aerosol generating substrate may include a homogenized tobacco material, an aerosol former, and a binder.

[0037] Nicotine may be present in the aerosol generating substrate in the range of about 0.5 to about 10% by weight of nicotine, or about 0.5 to about 5% by weight of nicotine. The aerosol generating substrate preferably contains about 1 to about 3% by weight of nicotine, or about 1.5 to about 2.5% by weight of nicotine, or about 2% by weight of nicotine.

[0038] The aerosol generating substrate may contain a flavoring agent. The plant material provides a flavoring agent that can impart flavor to the taste of the aerosol produced by the aerosol generating article. A flavoring agent is any natural or artificial compound that affects the sensory properties of the aerosol. Non-limiting examples of flavoring agent sources include mint (such as peppermint and Dutch mint), coffee, tea, cinnamon, clove, cocoa, vanilla, eucalyptus, geranium, agave, and nez, and combinations thereof.

[0039] The aerosol generating substrate may contain an essential oil. The essential oil provides a flavoring agent that can impart flavor to the taste of the aerosol produced by the aerosol generating article. Suitable essential oils include, but are not limited to, eugenol, peppermint oil, and Dutch mint oil. A preferred essential oil is eugenol. The essential oil may be present in the aerosol generating substrate in an amount of at least about 0.1% by weight, or at least about 0.5% by weight, or at least about 1% by weight. The essential oil may be present in the aerosol generating substrate in the range of about 0.1% by weight to about 10% by weight, or about 0.1% by weight to about 5% by weight, or about 0.5% by weight to about 2% by weight.

[0040] The aerosol generating substrate may include a gel composition. The term "gel" refers to a solid at room temperature. In this context, "solid" means that the gel has a stable size and shape and does not flow. Room temperature in this context means 25 degrees Celsius. A gel can be defined as a substantially diluted cross-linked system that does not exhibit fluidity in the steady state. By weight, gels can be mostly liquid, and they exhibit solid-like behavior due to a three-dimensional cross-linked network within the liquid. It is the cross-linking within the fluid that gives the gel its structure (hardness). Thus, a gel can be a dispersion of liquid molecules within a solid in which liquid particles are dispersed in a solid medium.

[0041] The gel composition may include a gelling agent that forms a solid medium, an aerosol former such as glycerin dispersed in the solid medium, and nicotine dispersed in the glycerin. The composition forms a stable gel phase. The gel composition may include at least two gelling agents that form a solid medium, glycerin dispersed in the solid medium, and nicotine dispersed in the glycerin. The composition forms a stable gel phase. The gel composition may include a thickening agent and a gelling agent that form a solid medium, glycerin dispersed in the solid medium, and nicotine dispersed in the glycerin. The composition forms a stable gel phase. The gel composition may include nicotine, an aerosol former, a thickening agent, a hydrogen bond cross-linked gelling agent, and an ion cross-linked gelling agent. The gel composition may further include a divalent cation.

[0042] The term "thickening agent" refers to a compound that, when homogeneously added in an amount of 0.3% by weight to a 50% by weight water / 50% by weight glycerin mixture at 25°C, increases the viscosity without causing gel formation and the mixture remains fluid or preservable. Preferably, the thickening agent, when homogeneously added in an amount of 0.3% by weight to a 50% by weight water / 50% by weight glycerin mixture at 25°C, at a shear rate of 0.1 s -1 without causing gel formation, increases the viscosity by at least 50 cPs, preferably at least 200 cPs, preferably at least 500 cPs, preferably at least 1000 cPs, and the mixture remains fluid or preservable. Preferably, the thickening agent, when homogeneously added in an amount of 0.3% by weight to a 50% by weight water / 50% by weight glycerin mixture at 25°C, at a shear rate of 0.1 s -1 without causing gel formation, increases the viscosity by at least 2 times, at least 5 times, at least 10 times, or at least 100 times greater than before addition, and the mixture remains fluid or preservable.

[0043] The viscosity values listed herein can be measured using a Brookfield RVT viscometer while rotating a disk type RV#2 spindle at a speed of 6 revolutions per minute (rpm) at 25°C.

[0044] The term "gelling agent" refers to a compound that, when added in an amount of about 0.3% by weight to a homogeneous mixture of 50% by weight water / 50% by weight glycerin, forms a solid medium or support matrix and leads to a gel. Examples of gelling agents include, but are not limited to, hydrogen bond cross-linked gelling agents and ionic cross-linked gelling agents.

[0045] The term "hydrogen bond cross-linked gelling agent" refers to a gelling agent that forms non-covalent cross-links or physical cross-links via hydrogen bonds. A hydrogen bond is a type of intermolecular electrostatic dipole-dipole interaction, rather than a covalent bond to a hydrogen atom. It results from the attraction between a hydrogen atom covalently bonded to a highly electronegative atom such as an N, O, or F atom and another highly electronegative atom.

[0046] The term "ionic cross-linked gelling agent" refers to a gelling agent that forms non-covalent cross-links or physical cross-links via ionic bonds. Ionic cross-linking involves the association of polymer chains through non-covalent interactions. When multivalent molecules with opposite charges are electrostatically attracted to each other and generate a cross-linked polymer network, the cross-linked network is formed.

[0047] The gel composition contains an aerosol former. Ideally, the aerosol former is substantially resistant to thermal degradation 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, glycerin, etc.), esters of polyhydric alcohols (such as glycerin monoacetate, diacetate, or triacetate, etc.), and aliphatic esters of monocarboxylic acids, dicarboxylic acids, or polycarboxylic acids (such as dimethyl dodecanedioate, dimethyl tetradecanedioate, etc.). The polyhydric alcohol or a mixture thereof can be one or more of triethylene glycol, 1,3-butanediol, and glycerin (glycerin or propane-1,2,3-triol) or polyethylene glycol. The aerosol former is preferably glycerin.

[0048] The gel composition can contain most of the aerosol former such as glycerin. The gel composition can contain a mixture of water and glycerin, and glycerin can form most (by weight) of the gel composition. Glycerin can form at least about 50% by weight of the gel composition. Glycerin can form at least about 60% by weight, or about 65% by weight, or about 70% by weight of the gel composition. Glycerin can form from about 70% to about 80% by weight of the gel composition. Glycerin can form from about 70% to about 75% by weight of the gel composition.

[0049] The gel composition preferably does not contain water or contains only a low level of water. When the gel composition does not contain water or contains only a low level of water, the gel composition can contain higher levels of aerosol former, gelling agent, thickening agent, and other compounds such as nicotine. Also, a gel composition that does not contain water or contains only a low level of water is simpler and requires less energy for vaporization. An aerosol formed from a gel composition that does not contain water or contains only a low level of water can be perceived by the user as not being so hot. Preferably, the gel composition contains less than about 40% by weight, preferably less than about 30% by weight, preferably less than about 25% by weight of water. The gel composition can contain less than about 20% by weight, or less than about 15% by weight, or less than about 10% by weight, or less than about 5% by weight of water. The gel composition preferably can contain some water. When the composition contains some water, the gel composition is more stable. Preferably, the gel composition contains at least about 1% by weight, or at least about 2% by weight, or at least about 5% by weight of water. Preferably, the gel composition contains at least about 10% by weight, or at least about 15% by weight of water. Preferably, the gel composition contains water in the range of about 15% to about 25% by weight.

[0050] The gel composition may contain a gelling agent that is a hydrogen bond crosslinked gelling agent and an ionic crosslinked gelling agent. The gel composition may further contain a thickener. The gelling agent may form a solid medium in which the aerosol former can be dispersed. The gelling agent may form a solid medium in which the aerosol former and water can be dispersed. The thickener combined with the hydrogen bond crosslinked gelling agent and the ionic crosslinked gelling agent surprisingly seems to support the solid medium and maintain the gel composition even when the gel composition contains a high level of glycerin.

[0051] The gel composition may contain a gelling agent in the range of about 0.4 wt% to about 10 wt%. Preferably, the gel composition may contain a gelling agent in the range of about 0.5 wt% to about 8 wt%. Preferably, the gel composition may contain a gelling agent in the range of about 1 wt% to about 6 wt%. Preferably, the gel composition may contain a gelling agent in the range of about 2 wt% to about 4 wt%. Preferably, the gel composition may contain a gelling agent in the range of about 2 wt% to about 3 wt%.

[0052] The gel composition may contain a thickener in the range of about 0.2 wt% to about 5 wt%. Preferably, the thickener is in the range of about 0.5 wt% to about 3 wt%. Preferably, the thickener is in the range of about 0.5 wt% to about 2 wt%. Preferably, the thickener is in the range of about 1 wt% to about 2 wt%.

[0053] The gel composition may contain a thickener, a hydrogen bond crosslinked gelling agent, and an ionic crosslinked gelling agent present in the gel composition in a total amount of about 1 wt% to about 8 wt%. Preferably, the gel composition may contain a thickener, a hydrogen bond crosslinked gelling agent, and an ionic crosslinked gelling agent present in the gel composition in a total amount of about 2 wt% to about 6 wt%. Preferably, the gel composition may contain a thickener, a hydrogen bond crosslinked gelling agent, and an ionic crosslinked gelling agent present in the gel composition in a total amount of about 3 wt% to about 5 wt%.

[0054] The gel composition may contain a thickener, a hydrogen-bond crosslinking gelling agent, and an ionic crosslinking gelling agent, each independently present in the gel composition at about 0.3 wt% to about 3 wt%. Preferably, the gel composition may contain a thickener, a hydrogen-bond crosslinking gelling agent, and an ionic crosslinking gelling agent, each independently present in the gel composition at about 0.5 wt% to about 2 wt%. Preferably, the gel composition may contain a thickener, a hydrogen-bond crosslinking gelling agent, and an ionic crosslinking gelling agent, each independently present in the gel composition at about 1 wt% to about 2 wt%.

[0055] The thickener may include one or more of xanthan gum, carboxymethyl cellulose, microcrystalline cellulose, methyl cellulose, gum arabic, guar gum, lambda carrageenan, or starch. The thickener preferably includes xanthan gum.

[0056] The gel composition may contain a thickener such as xanthan gum in the range of about 0.2 wt% to about 5 wt%. Preferably, xanthan gum may be in the range of about 0.5 wt% to about 3 wt%. Preferably, xanthan gum may be in the range of about 0.5 wt% to about 2 wt%. Preferably, xanthan gum may be in the range of about 1 wt% to about 2 wt%.

[0057] The hydrogen-bond crosslinking gelling agent may include one or more of galactomannan, gelatin, agarose, or konjac gum, or agar. The hydrogen-bond crosslinking gelling agent may preferably include agar in some cases.

[0058] The gel composition may contain a hydrogen-bond crosslinking gelling agent such as agar in the range of about 0.3 wt% to about 5 wt%. Preferably, the gel composition may contain a hydrogen-bond crosslinking gelling agent in the range of about 0.5 wt% to about 3 wt%. Preferably, the gel composition may contain a hydrogen-bond crosslinking gelling agent in the range of about 1 wt% to about 2 wt%.

[0059] The ionic crosslinking gelling agent may include low acyl gellan, pectin, kappa carrageenan, iota carrageenan, or alginate. The ionic crosslinking gelling agent may preferably include low acyl gellan.

[0060] The gel composition may include an ionic crosslinking gelling agent such as low acyl gellan in the range of about 0.3 wt% to about 5 wt%. Preferably, the gel composition may include the ionic crosslinking gelling agent in the range of about 0.5 wt% to about 3 wt%. Preferably, the composition may include the ionic crosslinking gelling agent in the range of about 1 wt% to about 2 wt%.

[0061] The gel composition may further include a divalent cation. The divalent cation preferably may include calcium ions such as calcium lactate in the solution. Divalent cations (such as calcium ions) may assist in gel formation of a composition containing a gelling agent such as an ionic crosslinking gelling agent. The ionic effect may assist in gel formation. The divalent cation may be present in the gel composition in the range of about 0.1 to about 1 wt%, or about 0.5 wt%.

[0062] The gel composition may further include an acid. The acid may include a carboxylic acid. The carboxylic acid may include a ketone group. Preferably, the carboxylic acid may include a ketone group having less than about 10 carbon atoms, or less than about 6 carbon atoms, or less than about 4 carbon atoms, such as levulinic acid or lactic acid. Preferably, this carboxylic acid has three carbon atoms (such as lactic acid). Lactic acid surprisingly improves the stability of the gel composition even more than similar carboxylic acids. The carboxylic acid may assist in gel formation. The carboxylic acid may reduce the change in nicotine concentration within the gel composition during storage.

[0063] The gel composition may include a carboxylic acid such as lactic acid in the range of about 0.1 wt% to about 5 wt%. Preferably, the carboxylic acid may be in the range of about 0.5 wt% to about 3 wt%. Preferably, the carboxylic acid may be in the range of about 0.5 wt% to about 2 wt%. Preferably, the carboxylic acid may be in the range of about 1 wt% to about 2 wt%.

[0064] Nicotine is included in the gel composition. Nicotine may be added to the composition in free base form or in salt form. The gel composition may contain from about 0.5 to about 10% by weight of nicotine, or from about 0.5 to about 5% by weight of nicotine. Preferably, the gel composition may contain from about 1 to about 3% by weight of nicotine, or from about 1.5 to about 2.5% by weight of nicotine, or about 2% by weight of nicotine. The nicotine component of the gel formulation may be the most volatile component of the gel formulation. In some embodiments, water may be the most volatile component of the gel formulation, and the nicotine component of the gel formulation may be the second most volatile component of the gel formulation.

[0065] The aerosol generating system may comprise a heat source, an aerosol generating substrate, at least one air intake downstream of the aerosol generating substrate, and an air flow path extending between the at least one air intake and the mouth-side end of the article. The heat source is preferably upstream of the aerosol generating substrate. The heat source may be integral with the aerosol generating device, and the aerosol generating article, which is a consumable, may be releasably received within the aerosol generating device.

[0066] The heat source may be a combustible heat source, a chemical heat source, an electrical heat source, a heat sink or any combination thereof. The heat source may be an electrical heat source and is preferably in the form of a blade that can be inserted into the aerosol generating substrate. Alternatively, the heat source may be configured to surround the aerosol generating substrate and, as such, may be in the form of a hollow cylinder or any other suitable form. Alternatively, the heat source is a combustible heat source. As used herein, a combustible heat source is a heat source that burns itself during use to generate heat, which is different from a cigarette, a cigar or a cigarillo, and the combustion of the aerosol generating substrate is not involved. The combustible heat source may comprise carbon and an ignition aid such as a metal peroxide, superoxide or nitrate, where the metal is an alkali metal or an alkaline earth metal.

[0067] The aerosol generating substrate may include an induction heater or susceptor, or a plurality of induction heaters or susceptors. The induction heater or susceptor is heated in the presence of an alternating or fluctuating electromagnetic field. When the heating is by induction heating, the fluctuating electromagnetic field is transmitted through the aerosol generating article to the induction heater or susceptor, as a result of which the susceptor or induction heater converts the fluctuating field into thermal energy to heat the aerosol generating substrate.

[0068] The induction heater or susceptor may be formed from any material that can be inductively heated to a temperature sufficient to generate aerosol from the aerosol generating substrate. The induction heater or susceptor may contain metal or carbon. Preferred induction heaters or susceptors may include ferromagnetic materials (such as ferrite iron), or ferromagnetic steel or stainless steel. The induction heater or susceptor may contain aluminum. The induction heater or susceptor may be formed from 400 series stainless steel, such as grade 410, or grade 420, or grade 430 stainless 20 steel. Different materials dissipate different amounts of energy when positioned within an electromagnetic field having similar values of frequency and magnetic field strength. The induction heater or susceptor is preferably heated to a temperature in excess of 250 degrees Celsius. However, the induction heater or susceptor is preferably heated to less than 350 degrees Celsius to prevent combustion of the material in contact with the susceptor.

[0069] The induction heater or susceptor may be disposed in proximity to the wrapper of the aerosol generating substrate, since the wrappers described herein advantageously resist combustion.

[0070] As used herein, the term "mouthpiece" refers to the portion of an aerosol generating article that is designed to contact the consumer's mouth. The mouthpiece may be the portion of the aerosol generating article that includes a filter, or in some cases, the mouthpiece may be defined by the extent of the tipping wrapper. In other cases, the mouthpiece may be defined as a portion of the aerosol generating article that extends from the mouth-side end of the aerosol generating article by about 40 mm, or by about 30 mm from the mouth-side end of the aerosol generating article.

[0071] The terms "upstream" and "downstream" refer to the relative positions between elements of the aerosol generating article as described in relation to the direction of the aerosol when drawn from the aerosol generating substrate and passing through the mouthpiece.

[0072] The terms "wrapper" or "paper wrapper" are interchangeable and refer to one or more layers of packaging material that surround the aerosol generating substrate, formed of paper, that contains the aerosol generating substrate or maintains the shape of the aerosol generating article. The wrapper reduces smudging on the outer surface of the aerosol generating article. The wrapper preferably contacts the aerosol generating substrate.

[0073] The term "hydrophobic" refers to a surface that exhibits the property of repelling water. One useful way to determine this is to measure the water contact angle. The "water contact angle" is the angle at which the liquid / vapor interface intersects the solid surface, which has conventionally been measured through the liquid. This quantifies the wettability of the solid surface by the liquid according to Young's equation. The hydrophobicity or water contact angle is determined using the TAPPI T558 test method, and the results are presented as the interfacial contact angle and reported in "degrees", but can range from approximately 0 to approximately 180 degrees.

[0074] Grease permeability is reported according to test method Tappi 559cm - 02, the classical method 2002. This test method determines the grease permeability of paper or wrapper. This test method measures the level of permeability by dropping a mixture of castor oil and solvent onto it. These mixtures are a set of 10 kits prepared with castor oil, n - heptane, and toluene as described in the following table. The total volume of one kit is 10 ml.

Table 1

[0075] The sample is placed on the black surface with the inspection side up. Starting from kit 1, a 25 - μL droplet is deposited on the paper using a micropipette fixed at a height of 13 mm above the sample. After 15 seconds, the excess is wiped clean, and immediately the surface of the paper is visually inspected to check if a dark spot appears. Next, the paper is removed, and carefully checked for the presence of a drop on the black surface. The results are reported as follows. · If only stain appears on the surface of the paper, the inspection of this kit is positive, and the result is "visible through". · If stain appears on the black surface, the inspection of this kit is positive, and the result is "pass through". · If there is no stain, the result of this kit is negative.

[0076] The test is repeated with the next kit until the result is "pass through" or the last test kit (kit 10) is reached. Once the appropriate test kit is identified, the measurement must be performed at least three times to confirm the "positive" stain.

[0077] The present disclosure relates to a wrapper for use in aerosol generating articles, the wrapper comprising a paper layer having low grease permeability or low grease staining and being utilisable with an aerosol generating substrate. According to the present disclosure, there is provided an aerosol generating article comprising an aerosol generating substrate containing nicotine and a wrapper disposed around the aerosol generating substrate. The wrapper has low grease permeability and has a negative result for at least one kit oil sample of Method Tappi 559cm-02, Classical Method 2002, preferably has a negative result for at least five kit oil samples of Method Tappi 559cm-02, Classical Method 2002, and preferably has a negative result for all ten kit oil samples of Method Tappi 559cm-02, Classical Method 2002, and comprises a paper layer.

[0078] The paper layer may have a thickness / grammage within the range of about 0.8 micrometers / gsm to about 1.2 micrometers / gsm. The paper layer may have a thickness / grammage within the range of about 1.0 micrometers / gsm to about 1.2 micrometers / gsm. The paper layer may have a thickness / grammage of about 1.0 micrometers / gsm. The paper layer may have a thickness / grammage of about 0.9 micrometers / gsm. The paper layer may have a thickness / grammage of about 1.0 micrometers / gsm. The paper layer may have a thickness / grammage of about 1.1 micrometers / gsm. The paper layer may have a thickness / grammage of about 1.2 micrometers / gsm.

[0079] The paper layer may have a thickness of less than about 50 micrometers, or less than about 40 micrometers. The paper layer may have a thickness within the range of about 10 micrometers to about 50 micrometers. The paper layer may have a thickness within the range of about 20 micrometers to about 50 micrometers. The paper layer may have a thickness within the range of about 30 micrometers to about 50 micrometers. The paper layer may have a thickness within the range of about 35 micrometers to about 50 micrometers. The paper layer may have a thickness within the range of about 35 micrometers to about 40 micrometers. The paper layer may have a thickness within the range of about 40 micrometers to about 50 micrometers.

[0080] The paper layer may have a basis weight within the range of about 25 gsm to about 45 gsm. The paper layer may have a basis weight within the range of about 30 gsm to about 45 gsm. The paper layer may have a basis weight within the range of about 35 gsm to about 45 gsm. The paper layer may have a basis weight within the range of about 35 gsm to about 40 gsm.

[0081] In one embodiment, the paper layer has a negative result for all kit oil samples of method Tappi 559cm - 02, classical method 2002.

[0082] In one embodiment, the paper layer has a negative result for all kit oil samples of method Tappi 559cm - 02, classical method 2002. This paper layer has a basis weight of about 35 gsm to about 40 gsm and a thickness of about 35 micrometers to about 45 micrometers.

[0083] In one embodiment, the paper layer has a negative result for all kit oil samples of method Tappi 559cm - 02, classical method 2002. This paper layer has a basis weight of about 35 gsm to about 40 gsm and a thickness of about 35 micrometers to about 45 micrometers. This paper layer has a water contact angle of about 35 degrees to about 50 degrees.

[0084] The paper layer preferably contains PVOH (polyvinyl alcohol) or silicon. In one embodiment, the paper layer contains PVOH (polyvinyl alcohol). PVOH may be applied to the paper layer as a surface coating. PVOH may be disposed on the outer surface of the paper layer of the aerosol generating article. PVOH may be disposed on the outer surface of the paper layer of the aerosol generating article to form a layer. PVOH may be disposed on the inner surface of the paper layer of the aerosol generating article. PVOH may be disposed on the inner surface of the paper layer of the aerosol generating article to form a layer. PVOH may be disposed on both the inner and outer surfaces of the paper layer of the aerosol generating article. PVOH may be disposed on both the inner and outer surfaces of the paper layer of the aerosol generating article to form a layer.

[0085] The paper layer may include a surface treatment containing PVOH or silicon. The paper layer may include a surface treatment containing PVOH. The paper layer may include a surface treatment containing silicon. This surface treatment may be applied to the outer surface of the paper layer. This surface treatment may be applied to the inner surface of the paper layer. This surface treatment may be applied to both the outer and inner surfaces of the paper layer. The addition of PVOH or silicon may improve the grease barrier properties of the paper layer.

[0086] The aerosol generating substrate may include a gel composition. The gel composition may include most of the aerosol former such as glycerin. The gel composition may include nicotine, at least about 50 wt% glycerin or at least 70 wt% glycerin, at least about 0.2 wt% of a hydrogen bond crosslinking gelling agent, at least about 0.2 wt% of an ionic crosslinking gelling agent, and at least about 0.2 wt% of a thickening agent. The gel composition may include xanthan gum.

[0087] The aerosol generating substrate may include a homogenized tobacco material. The tobacco homogenized tobacco material may include, on a dry mass basis, about 1% to about 5% binder and about 5% to about 30% of the aerosol former tobacco material.

[0088] The aerosol generating substrate may include a metal induction heating element. The metal induction heating element may include a plurality of metal induction heating elements. The metal induction heating element may include one metal induction heating element.

[0089] The wrapper described herein is intended to reduce and prevent the formation of stains on the aerosol generating article visible to the consumer. It has been observed that stains may appear on the aerosol generating article when stored in a high humidity environment or during consumption. The stain may be due to the absorption of water or aerosol forming substances (including any colored substances in suspension or solution) into the web of cellulosic fibers constituting the wrapper. Without being bound by any theory, the water or aerosol forming substance interacts with the cellulosic fibers of the paper, changing the fiber structure, and as a result, locally changing optical properties such as brightness, color, and opacity, and mechanical properties such as the tensile strength and permeability of the wrapper.

[0090] The wrapper described herein is intended to reduce and prevent the expansion of the aerosol generating article. By reducing or preventing the expansion of the aerosol generating article, the usefulness of the aerosol generating article is improved, and the aerosol generating article can be reliably inserted into and removed from the heating device without damaging the aerosol generating article.

[0091] The wrapper is part of the aerosol generating article and is arranged around the aerosol generating substrate to help maintain the cylindrical shape of the aerosol generating article. The wrapper may accommodate the aerosol generating substrate over at least about 50% of the length of the plug of the aerosol generating substrate. Preferably, the wrapper accommodates the aerosol generating substrate over at least about 90% of the length of the plug of the aerosol generating substrate. More preferably, the wrapper accommodates the aerosol generating substrate over at least about 100% of the length of the plug of the aerosol generating substrate.

[0092] This wrapper may exhibit a range of permeability, including non-permeability. The permeability of cigarette paper is determined using the international standard test method ISO 2965:2009, and the results are presented in cubic centimeters per minute per square centimeter and are referred to as "Coresta units". The permeability of the wrapper described herein is in the range of about 1 to about 10 Coresta units, about 5 to about 20 Coresta units, or about 1 to about 5 Coresta units.

[0093] The wrapper can be formed from any cellulosic material such as paper, wood, fabric, natural fibers, and artificial fibers. The wrapper preferably does not contain fillers such as calcium carbonate. The wrapper is preferably formed of at least 90% by weight of cellulosic material. The wrapper is preferably formed of at least 95% by weight of cellulosic material.

[0094] The paper layer can be formed from any cellulosic material such as paper, wood, fabric, natural fibers, and artificial fibers. The paper layer preferably does not contain fillers such as calcium carbonate. The paper layer is preferably formed of at least 90% by weight of cellulosic material. The paper layer is preferably formed of at least 95% by weight of cellulosic material.

[0095] The surface of the paper layer may have a water contact angle of at least about 30 degrees, at least about 35 degrees, at least about 40 degrees, or at least about 45 degrees. Hydrophobicity or water contact angle is determined using the TAPPI T558 test, and the results are presented as the interfacial contact angle and reported in "degrees", but can range from approximately 0 degrees to approximately 180 degrees.

[0096] The paper layer may have a negative result (no visible stain) for at least one kit oil sample of method Tappi 559cm - 02 classical method 2002. The paper layer may have a negative result for at least five kit oil samples, or all ten kit oil samples of method Tappi 559cm - 02 classical method 2002.

[0097] The wrapper may include two paper layers, the first layer having a negative result for at least one kit oil sample of the Tappi 559cm-02 classical method 2002, and the second paper having a negative result for at least one kit oil sample of the Tappi 559cm-02 classical method 2002. The wrapper has a total thickness of less than about 80 micrometers.

[0098] The wrapper may include two paper layers where the first layer contacts the aerosol-forming substrate and the second layer overlays the first layer. The first layer may contain PVOH (polyvinyl alcohol) or silicon, or may include a surface treatment containing PVOH or silicon. The second layer may contain PVOH (polyvinyl alcohol) or silicon, or may include a surface treatment containing PVOH or silicon. Both the first and second layers may contain PVOH (polyvinyl alcohol) or silicon, or may include a surface treatment containing PVOH or silicon. Only the first layer may contain PVOH (polyvinyl alcohol) or silicon, or may include a surface treatment containing PVOH or silicon. Only the second layer may contain PVOH (polyvinyl alcohol) or silicon, or may include a surface treatment containing PVOH or silicon.

[0099] An aerosol-generating article comprises an aerosol-generating substrate that may include charging of the tobacco surrounded by the wrapper described herein. The aerosol-generating substrate may, in any suitable form, include any suitable type or types of tobacco material or tobacco substitutes. The aerosol-generating substrate may include fire-cured tobacco, Burley tobacco, Maryland tobacco, Oriental leaf tobacco, specialty tobacco, homogenized or reconstituted tobacco or any combination thereof. The aerosol-generating substrate may be provided in the form of tobacco cut filler, tobacco laminas, processed tobacco materials such as volume-expanded or puffed tobacco, processed tobacco stems such as cut rolled or cut puffed stems, homogenized tobacco, reconstituted tobacco, cast leaf tobacco, mixtures thereof and the like. The term "tobacco cut filler", as used herein, refers to a tobacco material formed primarily from the lamina portion of tobacco leaves. As used herein, the term "tobacco cut filler" refers to both a single species of tobacco genus and two or more species of tobacco genus forming a tobacco cut filler blend.

[0100] As used herein, the term "homogenized tobacco" means a material formed by aggregating particulate tobacco. Homogenized tobacco can include reconstituted tobacco or cast leaf tobacco, or a mixture of both. The term "reconstituted tobacco" means a paper-like material that can be manufactured from tobacco by-products such as tobacco fines, tobacco dust, tobacco stems, or mixtures thereof. Reconstituted tobacco can be manufactured by extracting soluble chemicals from the tobacco by-products, processing the remaining tobacco fibers into a sheet, and re-applying the concentrated form of the extracted material onto the paper. As used herein, the term "cast leaf tobacco" means a product resulting from a process well-known in the art, which basically involves the process of placing a slurry containing ground tobacco particles and a binder (e.g., guar) on a support surface (such as a belt conveyor), drying the slurry, and removing the dried sheet from the support surface. Exemplary methods for manufacturing these types of aerosol-generating substrates are described in US 5,724,998, US 5,584,306, US 4,341,228, US 5,584,306, and US 6,216,706. Homogenized tobacco can be formed into a sheet that is crimped, rolled, folded, or otherwise compressed prior to being packaged to form a rod. For example, a sheet of homogenized tobacco material for use in the present invention can be crimped using a crimping unit of the type described in CH-A-691156, which comprises a pair of rotatable crimping rollers. However, of course, a sheet of homogenized tobacco material for use in the present invention can be textured using other suitable machinery and processes that deform or perforate the homogenized tobacco material sheet.

[0101] The aerosol generation substrates used in aerosol generating articles generally contain higher levels of aerosol formers than combustion smoking articles such as cigarettes. Humectants can also be referred to as "aerosol formers". Aerosol formers are used to describe any suitable known compound or mixture of compounds that, in use, facilitate the formation of an aerosol and are substantially resistant to thermal decomposition at the temperature of use of the aerosol generation substrate. Suitable aerosol formers are known in the art and include polyhydric alcohols (such as propylene glycol, triethylene glycol, 1,3 - butanediol, glycerin, etc.), esters of polyhydric alcohols (such as glycerin monoacetate, diacetate, triacetate, etc.), and aliphatic esters of monocarboxylic, dicarboxylic or polycarboxylic acids (such as dimethyl dodecanedioate, dimethyl tetradecanedioate, etc.), but are not limited thereto. Preferred aerosol formers are polyhydric alcohols (such as propylene glycol, triethylene glycol, 1,3 - butanediol, and most preferably glycerin or the like) or mixtures thereof. The aerosol generation substrate may contain a single aerosol former. Alternatively, the aerosol generation substrate may contain a combination of two or more aerosol formers.

[0102] The aerosol generation substrate can have a high level of aerosol former. As used herein, a high level of aerosol former means an aerosol former content of greater than about 10% by weight, or preferably greater than about 15% by weight, or more preferably greater than about 20% by weight. The aerosol forming substrate can also have an aerosol former content of from about 10% by weight to about 30% by weight, from about 15% by weight to about 30% by weight, or from about 20% by weight to about 30% by weight. The aerosol forming substrate can also have a glycerin content of from about 10% by weight to about 30% by weight, from about 15% by weight to about 30% by weight, or from about 20% by weight to about 30% by weight.

[0103] The aerosol generating substrate may contain at least about 1%, or at least about 2%, or at least about 5%, or at least about 7%, or at least about 10%, or at least about 12%, or at least about 15%, or at least about 18% of an aerosol former by weight. The aerosol generating substrate may contain an aerosol former in the range of about 1% to about 20%, or about 5% to about 20%, or about 10% to about 20% by weight.

[0104] The aerosol generating substrate may contain at least about 1%, or at least about 2%, or at least about 5%, or at least about 7%, or at least about 10%, or at least about 12%, or at least about 15%, or at least about 18% of glycerin by weight. The aerosol generating substrate may contain glycerin in the range of about 1% to about 20%, or about 5% to about 20%, or about 10% to about 20% by weight.

[0105] The aerosol generating substrate in gel form may have most of the aerosol former, preferably glycerin. The gel composition may contain a gelling agent that forms a solid medium, an aerosol former such as glycerin dispersed in the solid medium, and nicotine dispersed in the glycerin. The composition forms a stable gel phase. The gel composition may contain at least two gelling agents that form a solid medium, glycerin dispersed in the solid medium, and nicotine dispersed in the glycerin. The composition forms a stable gel phase. The gel composition may contain a thickening agent and a gelling agent that form a solid medium, glycerin dispersed in the solid medium, and nicotine dispersed in the glycerin. The composition forms a stable gel phase. The gel composition may contain nicotine, an aerosol former, a thickening agent, a hydrogen-bond crosslinked gelling agent, and an ion-crosslinked gelling agent. The gel composition may further contain a divalent cation.

[0106] The gel composition can include most of the aerosol former such as glycerin. The gel composition can include a mixture of water and glycerin, and glycerin can form most (by weight) of the gel composition. Glycerin can form at least about 50% by weight of the gel composition. Glycerin can form at least about 60% by weight, or about 65% by weight, or about 70% by weight of the gel composition. Glycerin can form from about 70% to about 80% by weight of the gel composition. Glycerin can form from about 70% to about 75% by weight of the gel composition.

[0107] The wrapper described herein is disposed around the aerosol generating substrate. The wrapper can reduce the absorption of the aerosol former compound and water into the wrapper when air is drawn through the heated aerosol generating article.

[0108] Preferably, the aerosol generating article can be substantially cylindrical. This enables a smooth flow of the aerosol. The aerosol generating article can have an outer diameter of, for example, 4 millimeters to 15 millimeters, 5 millimeters to 10 millimeters, or 6 millimeters to 8 millimeters. The aerosol generating article can have a length of, for example, 10 millimeters to 60 millimeters, 15 millimeters to 50 millimeters, or 20 millimeters to 45 millimeters.

[0109] The draw resistance (RTD) of an aerosol-generating article varies, inter alia, according to the length and dimensions of the passageway, the size of the openings, the dimensions of the smallest cross-sectional area of the internal passageway, and the materials used. The RTD of an aerosol-generating article can be from 50 millimeters of water column (mm H2O) and 140 millimeters of water column (mm H2O), from 60 millimeters of water column (mm H2O) to 120 millimeters of water column (mm H2O), or from 80 millimeters of water column (mm H2O) to 100 millimeters of water column (mm H2O). The RTD of an article refers to the static pressure difference between one or more openings of the article and the mouth-end when crossing the inner longitudinal-axis passageway under steady-state conditions where the volumetric flow rate is 17.5 milliliters per second at the mouth-end. The RTD of a specimen can be measured using the method described in ISO standard 6565:2002.

[0110] All scientific and technical terms used in this specification have the meanings commonly used in the art, unless otherwise specified. The definitions provided in this specification are for the purpose of facilitating the understanding of specific terms frequently used in this specification.

[0111] As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include embodiments having a plural referent, unless the context clearly dictates otherwise.

[0112] The term “or” as used in this specification and the appended claims is generally used in the sense of “and / or,” unless the context clearly dictates otherwise.

[0113] As used herein, the terms "have", "having", "include", "including", "comprise", "comprising", or the like are used in an unrestricted sense and generally mean "including but not limited to". Of course, "consisting essentially of", "consisting of", and the like are subsumed under "comprising" and the like.

[0114] The terms "preferred" and "preferably" refer to embodiments of the present invention that may provide certain advantages under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Moreover, the listing of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the present disclosure, including the claims.

Brief Description of the Drawings

[0115]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0116] The aerosol generating articles shown in FIGS. 1-4 illustrate one or more embodiments of the above-described aerosol generating articles or components of aerosol generating articles. The schematic diagrams are not necessarily to scale and are presented for illustrative purposes and not for limitation. The drawings depict one or more aspects described in the present disclosure. However, other aspects not depicted in the drawings are also within the scope and spirit of the present disclosure.

[0117] The aerosol generating article 10 of FIG. 1 exemplifies an aerosol generating substrate 12 including a tobacco plug, a hollow cellulose acetate tube 14, a polylactic acid filter segment 16, and a mouthpiece segment 18 formed of a cellulose acetate material. These four elements are individually wrapped with paper layers. In particular, the aerosol generating substrate 12 is wrapped with a first paper layer 50 as described herein. These four elements are arranged in a longitudinal alignment with ends touching end.

[0118] The aerosol generating substrate 12, the hollow cellulose acetate tube 14, and the polylactic acid filter segment 16 are joined together and surrounded by a second paper layer 20 to form an intermediate article. The mouthpiece segment 18 is joined to the intermediate article by tipping paper 25 to form the aerosol generating article 10. The first paper layer 50 and the second paper layer 20 may cooperate to form a wrapper as described herein.

[0119] The aerosol generating article 10 has a mouth-side end 22 and an upstream distal end 24 located at the end of the article opposite the mouth-side end 22. The aerosol generating article 10 shown in FIG. 1 is particularly suitable for use in an electrically operated aerosol generating device that includes a heater for heating the aerosol generating substrate 12.

[0120] The aerosol-generating article 100 of FIG. 2 comprises four coaxially aligned elements: an end plug 600 with a high draw resistance (RTD) at the distal end 103, a first paper layer 500 surrounding the aerosol-generating substrate 124, a fluid guide 400, and a mouthpiece 170 at the proximal end 101. These four elements are arranged sequentially and surrounded by a second paper layer 110 to form the aerosol-generating article 100. The aerosol-generating article 100 has a proximal end or mouth-side end 101 and a distal end 103 located at the end of the aerosol-generating article 100 opposite the proximal end 101. The first paper layer 500 and the second paper layer 110 may cooperate to form a wrapper, as described herein.

[0121] The aerosol-generating article 100 of FIG. 3 illustrates a cutaway view of an example of an aerosol-generating article 100 that is suitable for heating using not only inductive heating but also a blade-like heating element.

[0122] The aerosol-generating article 100 comprises a first paper layer 500 that surrounds, in order from proximal to distal, a mouthpiece 170, a fluid guide 400, a cavity 700, an aerosol-generating substrate 124, and a plug 600 at the proximal end 101. In this example, the aerosol-generating substrate 124 comprises a gel and a susceptor (not shown). The susceptor in this embodiment is a single strip of aluminum located centrally along the longitudinal axis of the aerosol-generating substrate 124. When the distal end 103 of the aerosol-generating article 100 is inserted into the aerosol-generating device 200 (see FIG. 6), the portion of the aerosol-generating article 100 is thereby positioned proximate to the induction heater 230 (see FIG. 5) of the aerosol-generating device 200. The electromagnetic radiation generated by the induction heater 230 is absorbed by the susceptor and aids in heating the aerosol-generating substrate 124 within the first paper layer 500, which in turn aids in the entrainment of nicotine into the aerosol passing through when a negative pressure is applied to the proximal end 101 of the aerosol-generating article 100, for example, during the release of material from the aerosol-generating substrate 124. Fluid, such as air, enters the outer longitudinal passage 831 through an opening (not shown), moves into the cavity 700 and then to the aerosol-generating substrate 124, where the fluid mixes with the aerosol-generating substrate 124 and entrains nicotine, then returns to the cavity and then exits at the proximal end 101 after passing through the inner longitudinal passage (not shown) of the fluid guide 400.

[0123] In this embodiment, the first paper layer 500 surrounds the aerosol-generating substrate 124, and the first paper layer 500 is surrounded by a second paper layer 110. The first paper layer 500 and the second paper layer 110 form a wrapper as described herein. The aerosol-generating substrate 124 may include a gel composition.

[0124] This aerosol-generating article 100 illustrated in FIGS. 2 and 3 may be used with an aerosol-generating device 200 as illustrated in FIGS. 5 and 6.

[0125] The aerosol-generating article 10 of FIG. 4 exemplifies an aerosol-generating substrate 12, a hollow cellulose acetate tube 14, a hollow tubular segment 16, and a mouthpiece segment 18. The aerosol-generating substrate 12 is wrapped with a first paper layer 50 as described herein. These four elements are arranged in end-to-end contact and aligned in the longitudinal direction, and are surrounded by a second paper layer 20 to form the aerosol-generating article 10. The first paper layer 50 and the second paper layer 20 may cooperate to form a wrapper as described herein.

[0126] The aerosol-generating article 10 has a mouth-side end 22 and an upstream distal end 24 located at the end of the article opposite to the mouth-side end 22. The aerosol-generating article 10 shown in FIG. 4 is particularly suitable for use in an electrically operated aerosol-generating device that includes a heater for heating the aerosol-generating substrate 12.

[0127] The aerosol-generating substrate 12 has a length of about 12 millimeters and a diameter of about 7 millimeters. The aerosol-generating substrate 12 has a cylindrical shape and a substantially circular cross-section. The aerosol-generating substrate 12 comprises an assembly of sheets of homogenized tobacco material. The sheets of homogenized tobacco material contain 10 weight percent glycerin on a dry basis. The hollow cellulose acetate tube 14 has a length of about 8 millimeters and a thickness of 1 millimeter. The mouthpiece segment 18 includes a plug of cellulose acetate tow that is 8 denier per filament and has a length of about 7 millimeters.

[0128] The hollow tubular segment 14 is provided as a cylindrical tube having a length of about 18 millimeters, and the wall thickness of the tube is about 100 micrometers. The aerosol generating article 10 includes a ventilation zone 26 provided about 5 millimeters upstream of the proximal end of the mouthpiece segment 18. Thus, the ventilation zone 26 is about 12 millimeters from the downstream end of the aerosol generating article, and about 13 millimeters from the upstream end of the hollow tubular segment. Thus, the ventilation zone 26 is about 21 millimeters from the downstream end of the aerosol generating substrate 12.

[0129] Figures 5-6 show examples of an aerosol generating article 100 and an aerosol generating device 200. The aerosol generating article 100 has a proximal or mouth-side end 101 and a distal end 103. In Figure 5, the distal end 103 of the aerosol generating article 100 is received within a receiving portion 220 of the aerosol generating device 200. The aerosol generating device 200 includes a housing 210 that defines a receptacle 220 configured to receive the aerosol generating article 100. The aerosol generating device 200 also includes a heating element 230 that forms a recess 235 configured to receive the aerosol generating article 100, preferably by interference fit. The heating element 230 may include an electrical resistance heating component. Further, the device 200 includes a power source 240 and control electronics 250 that cooperate to control the heating of the heating element 230.

[0130] The heating element 230 may heat the distal end 103 of the aerosol generating article 100. In this embodiment, the aerosol generating substrate 124 includes a gel containing nicotine. Heating the aerosol generating article 100 generates an aerosol containing nicotine in the aerosol generating substrate 124, and the aerosol can move out from the aerosol generating article 100 at the proximal end 101. The aerosol generating device 200 includes a housing 210. Figures 5-6 do not show the exact heating mechanism.

[0131] In some examples, the heating mechanism may be by conductive heating in which heat is transferred from the heating element 230 of the aerosol generating device 200 to the aerosol generating article 100. This can be easily done when the aerosol generating article 100 is positioned within the receiving portion 220 of the aerosol generating device 200 and the distal end 103 (preferably the end where the aerosol generating substrate 124 is located), and thus when the aerosol generating article 100 contacts the heating element 230 of the aerosol generating device 200. In certain embodiments, the heating element comprises a heating blade that protrudes from the aerosol generating device 200 and penetrates into the aerosol generating article 100 to directly contact the aerosol generating substrate 124.

[0132] In this example, the heating mechanism is by induction in which the heating element emits radiative magnetic radiation that is absorbed by the tubular element when the aerosol generating article 100 is positioned within the container 220 of the aerosol generating device 200.

[0133] When the aerosol generating article 100 is releasably received within the aerosol generating device 200 and on the heating element 230, the aerosol generating device 200 is activated to heat the aerosol generating substrate 124 to a temperature of approximately 375 degrees Celsius. When the user sucks on the mouth-side end 101 of the aerosol generating article 100, the volatile compounds released from the aerosol generating substrate 124 are drawn downstream through the aerosol generating article 100 and condense to form an aerosol that is drawn into the user's mouth through the mouthpiece 101 of the aerosol generating article 100. The wrappers 500, 110 repel aerosol-forming substances and moisture from the aerosol, reducing soiling and weakening of the wrappers 500, 110.

[0134] The first paper layers 50, 500 have a negative result for at least one kit oil sample of the Tappi 559cm - 02 classical method 2002. Preferably, the first paper layers 50, 500 have a negative result for at least five kit oil samples of the Tappi 559cm - 02 classical method 2002. Preferably, the paper layers 50, 500 have a negative result for all ten kit oil samples of the Tappi 559cm - 02 classical method 2002.

[0135] The first paper layers 50, 500 preferably have a thickness / grammage of about 1.2 micrometers / gsm or less, and a water contact angle of at least about 30 degrees. The first paper layers 50, 500 may have a thickness of less than about 50 micrometers, or less than about 40 micrometers. The first paper layers 50, 500 may have a grammage in the range of about 25 gsm to about 45 gsm, or about 35 gsm to about 40 gsm.

[0136] The first paper layers 50, 500 preferably have a water contact angle of at least about 30 degrees, and an elongation at break ratio CD / MD of about 2.5 or less. The first paper layers 50, 500 may have an elongation at break ratio CD / MD of about 2.2 or less, or about 2 or less.

[0137] The first paper layers 50, 500 preferably have an elongation at break ratio with CD / MD of about 2.5 or less, and a negative result for at least one kit oil sample of the Tappi 559cm - 02 classical method 2002. The first paper layers 50, 500 may have a negative result for at least five kit oil samples, or all ten kit oil samples of the Tappi 559cm - 02 classical method 2002.

[0138] The wrapper includes a first paper layer 50, 500, and a second paper layer 20, 110, and the first paper layer 50, 500 preferably has a negative result for at least one kit oil sample of the Tappi 559cm - 02 classical method 2002, or a negative result for at least five kit oil samples of the Tappi 559cm - 02 classical method 2002, or a negative result for all ten kit oil samples of the Tappi 559cm - 02 classical method 2002.

[0139] The wrapper includes a first paper layer 50, 500, and a second paper layer 20, 110, and the first paper layer 50, 500 has a negative result for at least one kit oil sample of the Tappi 559cm - 02 classical method 2002, and preferably the wrapper can have a total thickness of less than about 80 micrometers.

[0140] The first paper layer 50, 500 preferably contains PVOH (polyvinyl alcohol) or silicon. The first paper layer 50, 500 may include a surface treatment containing PVOH or silicon. The addition of PVOH (polyvinyl alcohol) or silicon may improve the grease barrier properties of the wrapper.

[0141] The second paper layer 20, 110 preferably contains PVOH (polyvinyl alcohol) or silicon. The second paper layer 20, 110 may include a surface treatment containing PVOH or silicon. The addition of PVOH (polyvinyl alcohol) or silicon may improve the grease barrier properties of the wrapper.

[0142] The above - mentioned exemplary embodiments are not limiting. Other embodiments consistent with the above - mentioned exemplary embodiments will be apparent to those skilled in the art.

Claims

1. An aerosol generating article, comprising: an aerosol generating substrate containing nicotine and at least 20 wt% glycerin; a wrapper disposed around and in contact with the aerosol generating substrate, the wrapper including a paper layer having a surface treatment such that the paper layer has a negative result for at least one kit oil sample of Method Tappi 559 cm-02, Classical Method 2002;

2. The aerosol generating article according to claim 1, wherein the paper layer has a negative result for at least 5 kit oil samples of Method Tappi 559 cm-02, Classical Method 2002.

3. The aerosol generating article according to any one of claims 1 to 2, wherein the paper layer has a negative result for all 10 kit oil samples of Method Tappi 559 cm-02, Classical Method 2002.

4. The aerosol generating article according to any one of claims 1 to 3, wherein the paper layer has a basis weight in the range of 25 g / m 2 to 45 g / m 2 and a thickness in the range of 35 micrometers to 50 micrometers.

5. The aerosol generating article according to any one of claims 1 to 4, wherein the paper layer contains PVA or silicon.

6. The aerosol generating article according to any one of claims 1 to 5, wherein the paper layer contains a surface treatment containing PVA or silicon.

7. The aerosol generating article according to any one of claims 1 to 6, wherein the paper layer contains PVA.

8. The aerosol generating article according to any one of claims 1 to 7, wherein the paper layer contains silicon.

9. The aerosol generating substrate contains a gel composition, and the gel composition contains at least 70 wt% of glycerin. The aerosol generating article according to claim 1.

10. The aerosol generating article according to claim 9, wherein the gel composition contains xanthan gum.

11. The aerosol generating article according to any one of claims 1 to 10, wherein the aerosol generating substrate contains a homogenized tobacco material.

12. The aerosol generating article according to any one of claims 1 to 11, wherein the aerosol generating substrate includes a metal induction heating element.

13. The aerosol generating article according to any one of claims 1 to 12, wherein the aerosol generating substrate includes a plurality of metal induction heating elements.

Images