Heat generating segment for aerosol generating system of smoking articles

Abstract

To provide a direct ignition smoking article to be readily ignited, and to remain ignited while being used by a smoker.SOLUTION: Provided is a fuel element 40 adapted for use in a smoking article 10, which comprises: a combustible carbonaceous material in an amount of at least 25% by dry weight based on the weight of the fuel element; and a particulate ignition aid dispersed throughout the fuel element and selected from ceramic particles, cellulose particles, fullerenes, impregnated activated carbon particles, inorganic salts, and combinations thereof, where the average particle size of the ignition aid is less than about 1,000 microns. Also provided are elongate smoking articles having a lighting end 14 and an opposite mouth end 18, and including the fuel element configured for ignition of the lighting end.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to products made from or derived from tobacco, or alternatively products incorporating tobacco, which are intended for human consumption, and more particularly to the components and configurations of non-combustion heated smoking articles.

Background Art

[0002] Conventional smoking articles such as cigarettes have a substantially cylindrical rod-like structure and include a filling, roll or column of smokable material such as shredded tobacco (e.g., in shredded filler form) surrounded by a wrapper, thereby forming a so-called "smokable rod", "tobacco rod" or "cigarette rod". Typically, a cigarette has a cylindrical filter element aligned end-to-end with the tobacco rod. Preferably, the filter element includes plasticized cellulose acetate tow surrounded by a paper material known as "plug wrap". Preferably, the filter element is attached to one end of the tobacco rod using a surrounding wrapper material known as "tipping paper". Further, it has become desirable to provide perforations in the tipping material and plug wrap to dilute the mainstream smoke drawn in with ambient air. Descriptions of cigarettes and these various components are set forth in Tobacco Production, Chemistry and Technology, Davis et al. (eds.) (1999), which is incorporated herein by reference. Traditional types of cigarettes are used by smokers by igniting this one end and burning the tobacco rod. The smoker then inhales the mainstream smoke into his or her oral cavity by sucking on the opposite end of the cigarette (e.g., the filter end or the mouth-side end). Over the years, efforts have been made to improve the components, structure and performance of smoking articles. See, for example, the background art disclosed in both U.S. Patent Nos. 7,503,330 and 7,753,056 to Borschke et al., which are incorporated herein by reference.

[0003] Certain types of cigarettes that use carbonaceous fuel elements have been marketed by the R.J. Reynolds Tobacco Company under the trade names "Premier", "Eclipse", and "Revo". See, for example, Chemical and Biological Studies on New Cigarette Prototypes that Heat Instead of Burn Tobacco, R.J. Reynolds Tobacco Company Monograph (1988) and Inhalation Toxicology, Vol. 12, No. 5, pp. 1-58 (2000) for such types of cigarettes. Further, a similar type of cigarette has recently been marketed in Japan by Japan Tobacco Inc. under the trade name "Steam Hot One". Additionally, various types of smoking products incorporating carbonaceous fuel elements for heat generation and aerosol formation have recently been described in the patent literature. See, for example, U.S. Patent No. 7,836,897 to Borschke et al.; U.S. Patent No. 8,469,035 to Banerjee et al. and U.S. Patent No. 8,464,726 to Sebastian et al.; U.S. Patent Publication No. 2012 / 0042885 to Stone et al.; U.S. Patent Publication No. 2013 / 0019888 to Tsuruizumi et al.; U.S. Patent Publication No. 2013 / 0133675 to Shinozaki et al. and U.S. Patent Publication No. 2013 / 0146075 to Poget et al.; PCT WO2012 / 0164077 to Gladden et al.; PCT WO2013 / 098380 to Raether et al.; PCT WO2013 / 098405 to Zuber et al.; PCT WO2013 / 098410 to Zuber et al.; PCT WO2013 / 104914 to Woodcock; PCT WO2013 / 120849 to Roudier et al.; PCT WO2013 / 120854 to Mironov; EP1808087 to Baba et al. and EP2550879 to Tsuruizumi et al., all of which are hereby incorporated by reference in their entirety.The historical perspective of technologies related to various types of smoking products incorporating carbonaceous fuel elements for heat generation and aerosol formation can be found, for example, in the Background of the Invention of U.S. Patent Publication No. 2007 / 0215167 to Llewellyn Crooks et al., which is also incorporated herein by reference.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

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Patent Document 15

[0005] [Non-Patent Document 1] Tobacco Production, Chemistry and Technology, Davis et al. (eds.) (1999) [Non-Patent Document 2] Chemical and Biological Studies on New Cigarette Prototypes that Heat Instead of Burn Tobacco, R.J. Reynolds Tobacco Company Monograph (1988) [Non-Patent Document 3] Inhalation Toxicology, Vol. 12: No. 5, pp. 1 - 58 (2000) [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] It is highly desirable to provide a smoking article that demonstrates the ability to provide a smoker with many of the benefits and advantages of conventional smoking without producing large amounts of incomplete combustion and pyrolysis products. In combination with such desirable features, a directly ignitable smoking article that is easily ignited and remains in an ignited state while being used by a smoker is also considered desirable. [Means for Solving the Problems]

[0007] The foregoing and other needs are met by aspects of the present disclosure, which in one aspect provides an elongate smoking article having a lit end and an opposite mouth end. Such a smoking article comprises a mouth end portion disposed at the mouth end and optionally includes a tobacco portion disposed between the lit end and the mouth end portion. An aerosol generating system is disposed between the lit end and the mouth end portion, and the aerosol generating system includes a heat generating portion disposed at the lit end that includes a combustible fuel element.

[0008] In one aspect of the invention, there is provided a combustible fuel element adapted for use in a smoking article, the fuel element comprising, on a dry weight basis, at least 25% by weight of a combustible carbonaceous material relative to the weight of the fuel element, and particulate ignition aids dispersed throughout the fuel element and selected from the group consisting of ceramic particles, cellulose particles, fullerenes, impregnated activated carbon particles, inorganic salts, and combinations thereof, wherein the average particle size of the ignition aids is less than about 1,000 microns, provided that when the ignition aid is an inorganic salt, the inorganic salt is present in an amount of about 0.5 dry weight % or less relative to the total dry weight of the fuel element. The particulate ignition aids are preferably non-catalytic. Exemplary impregnants for activated carbon include metals, metal oxides, inorganic salts, and inorganic acids. The ignition aids improve the operation of the fuel element by reducing the amount of time required to ignite the fuel element.

[0009] In certain embodiments, the ignition aids include ceramic particles or cellulose particles having an average particle size of less than about 500 microns, and the ceramic particles are glass bubbles or cenospheres. For example, the ignition aids can include glass bubbles having an average particle size of from about 10 to about 300 microns. Alternatively, the ignition aids can include cellulose particles having an average particle size of from about 10 to about 300 microns. In certain embodiments, the ceramic particles of the ignition aids are metal-coated ceramic particles. In certain embodiments, the presence of the ignition aids reduces the time required to ignite the fuel element by at least 20% compared to a control fuel element without the ignition aids.

[0010] The fuel element may include a binder, a catalytic metal material, graphite, an inorganic filler, and further components such as combinations thereof. In one embodiment, the fuel element comprises at least about 30% by dry weight of a combustible carbonaceous material, based on the dry weight of the fuel element, from about 0.1% to about 20% by dry weight of an ignition aid, at least about 5% by dry weight of a binder (e.g., a natural gum such as guar gum), at least about 5% by dry weight of graphite, and at least about 25% by dry weight of an inorganic filler (e.g., calcium carbonate).

[0011] In another aspect, the present invention provides an elongate smoking article having a lit end and an opposite mouth end, the smoking article comprising a mouth end portion disposed at the mouth end, a tobacco portion disposed between the lit end and the mouth end portion, and an aerosol generating system disposed between the lit end and the tobacco portion, the aerosol generating system including a heat generating portion disposed at the lit end, the heat generating portion including a fuel element according to any of the embodiments described above and being configured to be actuated by ignition of the lit end.

[0012] In a particular embodiment, the present invention provides an elongate smoking article having a lit end and an opposite mouth end, the smoking article comprising a mouth end portion disposed at the mouth end, a tobacco portion disposed between the lit end and the mouth end portion, and an aerosol generating system disposed between the lit end and the tobacco portion thereby comprising, the aerosol generating system including a heat generating portion disposed at the lit end, the heat generating portion including a fuel element configured to ignite the lit end, the fuel element comprising (a) at least about 30% by dry weight of a combustible carbonaceous material, based on the dry weight of the fuel element, (b) A non-catalytic ignition aid comprising ceramic particles or cellulose particles having an average particle size of less than about 500 microns and being from about 0.1% to about 20% on a dry weight basis, (c) A binder of at least about 5% on a dry weight basis, (d) At least about 5% of graphite on a dry weight basis, and (e) An inorganic filler of at least about 25% on a dry weight basis and comprising The ceramic particles are glass bubbles or cenospheres.

[0013] In yet another aspect of the present invention, an elongate smoking article having a lit end and an opposite mouth end is provided, the smoking article including a mouth end portion (e.g., a filter element) disposed at the mouth end, and an aerosol generation system disposed between the lit end and the mouth end portion, the aerosol generation system including a heat generating portion disposed at the lit end, the heat generating portion including a fuel element configured to ignite the lit end, the fuel element including a combustible carbonaceous material in an amount of at least 25% on a dry weight basis relative to the weight of the fuel element, the aerosol generation system including an aerosol generation portion including a plurality of aerosol generating elements in the form of beads or pellets including at least one aerosol forming material, the aerosol generating elements being treated with smoke. Exemplary beads or pellets are treated with wood smoke such as that generated by wood selected from hickory, maple, oak, apply, cherry, mesquite, and combinations thereof.

[0014] The aerosol generating elements can further include one or more of particulate tobacco, tobacco extracts, and nicotine, the nicotine being in the form of a free base, complex, or salt as a solvate. Further, the aerosol generating elements can further include one or more fillers, binders, flavorings, and combinations thereof. Exemplary aerosol forming materials include glycerin, propylene glycol, water, saline, nicotine, and combinations thereof.

[0015] Accordingly, the present disclosure includes, without limitation, the following embodiments:

[0016] Embodiment 1: A fuel element for use in a smoking article, comprising a combustible carbonaceous material in an amount of at least 25% on a dry weight basis relative to the weight of the fuel element, and particulate ignition aids dispersed throughout the fuel element and selected from the group consisting of ceramic particles, cellulose particles, fullerenes, impregnated activated carbon particles, inorganic salts, and combinations thereof, wherein the average particle size of the ignition aids is less than about 1,000 microns, provided that when the ignition aid is an inorganic salt, the inorganic salt is present in an amount of about 0.5 dry weight % or less relative to the total dry weight of the fuel element.

[0017] Embodiment 2: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the particulate ignition aid is non-catalytic.

[0018] Embodiment 3: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the ignition aid comprises ceramic particles or cellulose particles having an average particle size of less than about 500 microns, and the ceramic particles are glass bubbles or cenospheres.

[0019] Embodiment 4: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the ignition aid comprises glass bubbles having an average particle size of from about 10 to about 300 microns.

[0020] Embodiment 5: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the ignition aid comprises cellulose particles having an average particle size of from about 10 to about 300 microns.

[0021] Embodiment 6: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the ceramic particles are metal-coated ceramic particles.

[0022] Embodiment 7: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the presence of an ignition aid reduces the time required to ignite the fuel element by at least 20% compared to a control fuel element without the ignition aid.

[0023] Embodiment 8: A fuel element according to any of the above or following embodiments, or a combination thereof, further comprising a binder, a catalytic metal material, graphite, an inorganic filler, and combinations thereof.

[0024] Embodiment 9: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the impregnating agent present in the activated carbon particles is selected from the group consisting of metals, metal oxides, inorganic salts, and inorganic acids.

[0025] Embodiment 10: (a) At least about 30% combustible carbonaceous material on a dry weight basis, based on the dry weight of the fuel element (b) An ignition aid between about 0.1% and about 20% on a dry weight basis, (c) At least about 5% binder on a dry weight basis, (d) At least about 5% graphite on a dry weight basis, and (e) At least about 25% inorganic filler on a dry weight basis A fuel element according to any of the above or following embodiments, or a combination thereof, comprising.

[0026] Embodiment 11: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the inorganic filler is calcium carbonate.

[0027] Embodiment 12: A fuel element according to any of the above or following embodiments, or a combination thereof, wherein the binder is natural rubber.

[0028] Embodiment 13: An elongated smoking article having a lighting end and an opposite mouth end, the smoking article comprising a mouth end portion disposed at the mouth end, a tobacco portion disposed between the lighting end and the mouth end portion, and an aerosol generation system disposed between the lighting end and the tobacco portion, the aerosol generation system including a heat generating portion disposed at the lighting end, the heat generating portion being configured to ignite the lighting end, the elongated smoking article comprising a fuel element according to any of the foregoing or following embodiments, or a combination thereof.

[0029] Embodiment 14: A smoking article according to any of the foregoing or following embodiments, or a combination thereof, wherein the ignition aid includes ceramic particles or cellulose particles having an average particle size of less than about 500 microns, and the ceramic particles are glass bubbles or cenospheres.

[0030] Embodiment 15: A smoking article according to any of the foregoing or following embodiments, or a combination thereof, wherein the ignition aid includes glass bubbles having an average particle size of from about 10 to about 300 microns.

[0031] Embodiment 16: A smoking article according to any of the foregoing or following embodiments, or a combination thereof, wherein the ignition aid includes cellulose particles having an average particle size of from about 10 to about 300 microns.

[0032] Embodiment 17: A smoking article according to any of the foregoing or following embodiments, or a combination thereof, wherein the ceramic particles are metal-coated ceramic particles.

[0033] Embodiment 18: A smoking article according to any of the foregoing or following embodiments, or a combination thereof, wherein the presence of the ignition aid reduces the time required to ignite the fuel element by at least 20% compared to a control fuel element without the ignition aid.

[0034] Embodiment 19: A smoking article of any of the above or following embodiments, or a combination thereof, further comprising a binder, a catalytic metal material, graphite, an inorganic filler, and combinations thereof.

[0035] Embodiment 20: An elongate smoking article having a lit end and an opposite mouth end, the smoking article comprising: A mouth end portion disposed at the mouth end, A tobacco portion disposed between the lit end and the mouth end portion, and An aerosol generation system disposed between the lit end and the tobacco portion Comprising: The aerosol generation system includes a heat generating portion disposed at the lit end, the heat generating portion includes a fuel element configured to ignite the lit end, and the fuel element includes: (a) At least about 30% combustible carbonaceous material on a dry weight basis, based on the dry weight of the fuel element, (b) A non-catalytic ignition aid comprising from about 0.1% to about 20% on a dry weight basis of ceramic particles or cellulose particles having an average particle size of less than about 500 microns, (c) At least about 5% binder on a dry weight basis, (d) At least about 5% graphite on a dry weight basis, and (e) At least about 25% inorganic filler on a dry weight basis Including: The ceramic particles are glass bubbles or cenospheres, An elongate smoking article.

[0036] Embodiment 21: An elongated smoking article having a lighting end and an opposite mouth end, the smoking article comprising a mouth end portion disposed at the mouth end and an aerosol generation system disposed between the lighting end and the mouth end portion, the aerosol generation system including a heat generating portion disposed at the lighting end, the heat generating portion including a fuel element configured to ignite the lighting end, the fuel element including a combustible carbonaceous material in an amount of at least 25% on a dry weight basis relative to the weight of the fuel element, the aerosol generation system including an aerosol generation portion including a plurality of aerosol generating elements in the form of beads or pellets containing at least one aerosol forming material, the aerosol generating elements being treated with smoke, the elongated smoking article.

[0037] Embodiment 22: A smoking article according to any of the above or following embodiments, or a combination thereof, wherein the beads or pellets are treated with wood smoke.

[0038] Embodiment 23: A smoking article according to any of the above or following embodiments, or a combination thereof, wherein the wood is selected from the group consisting of hickory, maple, oak, apple, cherry, mesquite and combinations thereof.

[0039] Embodiment 24: A smoking article according to any of the above or following embodiments, or a combination thereof, wherein the aerosol generating elements further comprise one or more of granular tobacco, tobacco extract and nicotine, and the nicotine is in the form of a free base, a complex or a salt in solvated form.

[0040] Embodiment 25: A smoking article according to any of the above or following embodiments, or a combination thereof, wherein the aerosol generating elements further comprise one or more fillers, binders, flavorings and combinations thereof.

[0041] Embodiment 26: The aerosol-forming material is selected from the group consisting of glycerin, propylene glycol, water, physiological saline, nicotine, and combinations thereof, for any of the smoking articles of the above or following embodiments, or combinations thereof.

[0042] These and other features, aspects, and advantages of the present disclosure will become apparent from a reading of the following detailed description in conjunction with the accompanying drawings, which are briefly described below. The present disclosure includes any combination of two, three, four, or more such features or elements, whether or not the features or elements of the present disclosure described herein are explicitly combined, or are listed in the description of the specific embodiments or the claims herein. The present disclosure is intended to be read integrally such that, unless the context of the present disclosure specifically dictates otherwise, any separable features or elements of the present disclosure in any of these aspects and embodiments are to be considered combinable, i.e., intended to be combinable.

[0043] Accordingly, since the present disclosure is described in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale.

Brief Description of the Drawings

[0044]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

DETAILED DESCRIPTION OF THE INVENTION

[0045] The present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the disclosure are shown. In fact, the disclosure can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Similarly, throughout the specification, numbers refer to elements such as.

[0046] The present invention provides a combustible fuel element suitable for use in certain smoking articles that are adapted to heat tobacco without burning it. Such smoking articles are sometimes referred to as "non-combustion heating" tobacco products. The fuel element of the present invention comprises a combustible carbonaceous material such as milled carbon powder (e.g., BKO carbon powder). Such combustible carbonaceous materials generally have a carbon content of more than about 60%, generally more than about 70%, often more than about 80%, and in most cases more than about 90% by dry weight, and can be characterized as consisting mainly of carbon, generally having a high carbon content such as that of a carbonaceous material. The amount of combustible carbonaceous material incorporated into the fuel element can vary, but is usually at least about 25% by weight of the fuel element, often at least about 30% by weight, and in most cases at least about 35% by weight, on a dry weight basis. Exemplary weight ranges for the combustible carbonaceous material are from about 25% to about 60% by dry weight, more typically from about 30% to about 50% by dry weight.

[0047] In addition to the combustible carbonaceous material, the fuel element of the present invention includes one or more ignition aids. As used herein, "ignition aid" refers to a component of the fuel element that shortens the time taken for the fuel element to ignite. Advantageously, the ignition aid is a non-catalytic material, meaning that, particularly with respect to gas-phase catalytic reactions such as the catalytic conversion of carbon monoxide to carbon dioxide, the ignition aid does not significantly participate in the catalytic reaction. Exemplary ignition aids include ceramic materials, cellulose materials, fullerenes, impregnated activated carbon materials, and combinations thereof. Without being bound by any particular theory of operation, the ignition aid is thought to shorten the ignition time of the fuel element of the present invention either by providing a lower ignition temperature or by increasing the available surface area of the primary combustible carbonaceous material compared to the primary combustible carbonaceous material.

[0048] The presence of the ignition aid shortens the time required to ignite the fuel element when using the ignition possibility test described in the experimental section of the present application. As mentioned in the ignition possibility test described herein, this objective is the self-sustaining ignition of the fuel element over a period of time, and by blowing on the smoking article containing the fuel element to see if this blow causes the fuel element to burn orange or red (which would seem to indicate that a strong combustion is occurring), it means that the fuel element remains ignited for at least 20 seconds after contact with an open flame. In certain embodiments, a smoking article containing a fuel element comprising an ignition aid as described herein exhibits an ignition time of less than about 4.5 seconds, such as less than about 4.0 seconds or less than about 3.5 seconds. The shortening of the ignition time can be characterized in terms of the shortening rate compared to a control fuel element without an ignition aid (however, it is essential that the rest be the same in the composition). For example, in certain embodiments, a smoking article containing a fuel element comprising an ignition aid as described herein exhibits an ignition time that is at least about 20% shorter, such as at least about 30% shorter or at least about 40% shorter, than the ignition time of the control smoking article.

[0049] The amount of ignition aid used in the fuel element can vary and depends in part on the selection of the ignition aid, the formulation of the fuel element, and the desired ignition characteristics. Typically, the ignition aid is present in an amount of at least about 0.01%, more typically at least about 0.05%, at least about 0.1% by dry weight, or at least about 0.5% by dry weight, based on the dry weight of the fuel element. The ignition aid is usually not used in amounts exceeding about 40% by dry weight, such as less than about 30% by dry weight, or less than about 25% by dry weight, or less than about 20% by dry weight. Typically, the ignition aid is present in an amount less than that of the combustible carbonaceous material. Advantageous ranges for the ignition aid are from about 0.01 dry weight % to about 10 dry weight %, or from about 0.01 dry weight % to about 5 dry weight %, or from about 0.01 dry weight % to 20 dry weight %.

[0050] It has surprisingly been found that very low levels of the ignition aids referred to herein can successfully shorten the ignition time of the fuel elements of the present invention. For example, in certain cases, the ignition aid is present in an amount of about 5 dry weight % or less (relative to the total weight of the fuel element), particularly about 2.5 dry weight % or less, or about 1.0 dry weight % or less. In some examples, the ignition aid can be present in any amount of about 0.5 dry weight % or less or about 0.25 dry weight % or less. In particular, it is noted that inorganic salts and ceramic materials can be successfully used at very low levels.

[0051] The ignition aid used in the present invention is usually in granular or particulate form (such granular or particulate matter is generally referred to herein as "particles"), and the particles of the ignition aid can be solid or hollow (e.g., particles containing cavities filled with gas). The particle size can vary, but the particles are usually sized within the range that can be referred to as microparticles or nanoparticles. Exemplary ranges include microparticles having an average particle size of from about 0.1 to about 1,000 microns, such as from about 10 to about 300 microns (e.g., from about 10 to about 50 microns). In an exemplary embodiment, the ignition aid is present in the form of microparticles having an average particle size of less than about 250 microns or less than about 200 microns or less than about 150 microns (e.g., from about 20 to about 250 microns). The nanoparticle size range includes particles having an average particle size of less than about 100 nm (e.g., from about 50 to about 100 nm). The overall shape of the particles can vary without departing from the present invention, and some shapes can be characterized as irregular. In some embodiments, the particles can be substantially spherical (e.g., microspheres).

[0052] The average primary particle size can be determined by visually examining a transmission electron microscope ("TEM") image or a scanning electron microscope ("SEM") image, measuring the particle diameter in the image, and calculating the average primary particle size of the particles measured based on the magnification of the TEM or SEM image. The primary particle size of a particle refers to the smallest diameter sphere that completely encloses the particle, and this measurement relates to individual particles as opposed to the aggregation of two or more particles. The size ranges mentioned above are the average values of particles having a size distribution. It is also possible to use mixtures of particles having various average particle sizes within the ranges mentioned herein (e.g., bimodal particle distributions). In certain embodiments, commercially available materials can be purchased and ground to the desired size using devices known in the art, such as bead mills, ball mills, hammer mills, etc.

[0053] In certain embodiments, the ignition aid is in the form of ceramic particles, preferably in a size range of about 1,000 microns or less. Such ceramic particles include non-combustible, inorganic metal-containing (including metalloid-containing oxides) oxides (e.g., alumina, silica, iron oxide, cerium oxide, zirconia, etc.) particles or non-oxide (e.g., carbide, boride, nitride, etc.) particles at the combustion temperature of the fuel element. In one embodiment, the ceramic particles are glass bubbles, sometimes referred to as microballoons or glass microsheres, which are hollow glass particles. Exemplary glass bubble materials include such substances marketed by 3M under the 3M (trademark) glass bubble series such as K20, S35, XLD3000, and XLD6000 materials. Other ceramic particle materials include those marketed as 3M (trademark) ceramic microsheres (e.g., W-210, W-410, or W-610), and inert ceramic materials marketed by Tipton Corporation as ceramic balls (e.g., BSS18) or high alumina balls (e.g., BSS99). In a further embodiment, the ceramic particles are cenospheres, which are understood to be hollow spheres formed mostly from silica and alumina and are produced as by-products of coal combustion. See, for example, cenospheres available from CenoStar Corporation or cenospheres available from Omya UK Ltd. under the trade name Fillite®. Optionally, the ceramic particles can be metal-coated using metals such as nickel, iron, copper, tin, silver, and gold. Exemplary metal-coated ceramics are available from the Federal Technology Group of Bozeman (MT) or the Accumet Materials Company of Ossining (NY). Without being bound by any particular theory of operation, the ceramic particles assist in the ignition of the fuel element (i.e., shorten the time required to ignite the fuel element) by increasing the surface area of the combustible carbonaceous material in the fuel element.)It is considered possible.

[0054] In another embodiment, the ignition aid is in the form of cellulose particles such as those available from Sigma-Aldrich under the trade name SIGMACELL, (e.g., made from cotton linters). Such cellulose materials are typically microparticles within the particle size range described above. Without being bound by any particular theory of operation, such materials have an ignition temperature lower than that of the combustible carbonaceous material of the fuel element referred to above, so the addition of the combustible cellulose material is considered to assist in the ignition of the fuel element.

[0055] In another embodiment, the ignition aid is fullerene, which is understood to refer to an allotrope of carbon atoms, usually in the shape of spheres, ellipses or tubes, particularly including carbon nanotubes.

[0056] In a further embodiment, the ignition aid is an impregnated activated carbon particle material. Exemplary activated carbon materials are impregnated with metals (e.g., Ag or Mg), metal oxides (e.g., ZnO, CaO, Al2O3, MgO, CuO, Cu / CrO, Fe2O3), inorganic salts (e.g., NaOH, KOH, KI, KMnO4, K2CO3 and Na2CO3), inorganic acids (e.g., H2SO4 or H3PO4), etc. One source of such materials is Calgon Corporation. Such impregnated carbon materials are typically microparticles within the particle size range described above. Without being bound by any particular theory of operation, the impregnated carbon material has an ignition temperature lower than that of the combustible carbonaceous material of the fuel element referred to above, so the addition of such a material is considered to assist in the ignition of the fuel element.

[0057] The ignition probability aids can also be in the form of various inorganic salts such as alkali metal salts or alkaline earth metal salts, and can usually also be in the form of oxides, halides or sulfates (including bisulfates). Examples include sodium chloride, sodium sulfate, magnesium chloride, magnesium sulfate, calcium chloride, calcium sulfate, potassium chloride, potassium sulfate, sodium bisulfate, and the like.

[0058] The fuel element usually also contains a binder that enhances the cohesiveness of the composition. Exemplary binders include natural rubbers (such as guar gum) or alginate substances (such as ammonium alginate or sodium alginate). The binder is usually present in an amount of about 5% to about 25% by dry weight of the fuel element (e.g., about 7.5 to about 15% by dry weight).

[0059] In addition to the primary carbonaceous material referred to above, the fuel element composition of the present invention can also include graphite. For example, the above fuel composition can further include at least about 2% by dry weight, at least about 5% by dry weight or at least about 7.5% by dry weight of powdered graphite based on the dry weight of the fuel element. Usually, the amount of graphite added to the fuel element composition does not exceed about 20% by dry weight. Graphite is usually added in the form of a powder having an average particle size of less than about 50 microns.

[0060] The fuel element composition can further include an inorganic filler such as calcium carbonate or sodium carbonate. The typical amount of such an inorganic filler includes at least about 1% by dry weight, at least about 5% by dry weight or at least about 10% by dry weight based on the dry weight of the fuel element. Usually, the amount of inorganic filler added to the fuel element composition does not exceed about 40% by dry weight and in most cases is less than about 35% by dry weight.

[0061] The fuel element composition may also include a catalytic metal material that can reduce the concentration of certain gas components in the mainstream smoke generated during use of a smoking article incorporating the fuel element. As used herein, "catalytic metal material" refers to an elemental metal or metal-containing compound that can react directly with one or more of the gas-phase components of the mainstream smoke generated by a smoking article so as to reduce the concentration of the gas-phase components, or can catalyze a reaction involving the gas-phase components of the mainstream smoke, or both. For example, certain catalytic metal materials can catalyze the oxidation of CO to CO2 in the presence of oxygen (i.e., an oxidation catalyst) to reduce the level of CO in the mainstream smoke. US 2007 / 0215168 to Banerjee, which is hereby incorporated by reference in its entirety, describes a smoking article that includes a fuel element treated with cerium oxide particles. The cerium oxide particles reduce the amount of carbon monoxide generated during use of the smoking article incorporating the treated fuel element. Further catalytic metal compounds are described in U.S. Patent No. 6,503,475 to McCormick, U.S. Patent No. 6,503,475 to McCormick, U.S. Patent No. 7,011,096 to Li et al., U.S. Patent No. 8,617,263 to Banerjee et al., and U.S. Patent Publication Nos. 2002 / 0167118 to Billiet, 2002 / 0172826 to Yadav, 2002 / 0194958 to Lee, 2002 / 014453 to Lilly Jr., 2003 / 0000538 to Bereman, and 2005 / 0274390 to Banerjee, each of which is hereby incorporated by reference in its entirety.

[0062] Examples of the metal components of the catalyst metal material include, but are not limited to, elements of Group IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB, elements of Group IIIA, elements of Group IVA, lanthanide series and actinide series alkali metals, alkaline earth metals, and transition metals. Specific exemplary metal elements include Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt, Cu, Ag, Au, Zn, Y, Ce, Na, K, Cs, Mg, Ca, B, Al, Si, Ge, and Sn. The catalyst metal material can be used in various solid particle forms, including precipitated metal particles, metal oxide particles (e.g., iron oxide, copper oxide, zinc oxide, and cerium oxide), and supported catalyst particles, and the catalyst metal compound is dispersed inside the porous support material. Combinations of catalyst metal materials can be used, such as a combination of a palladium catalyst and cerium oxide. The particle size of the catalyst metal material can vary, but is typically from about 1 nm to about 10 microns. The amount of the catalyst metal material used can vary, but is typically in an amount of at least about 2.5 dry weight %, at least about 5 dry weight %, or at least about 10 dry weight % based on the dry weight of the fuel element. The catalyst metal material is typically present in an amount of less than about 35 dry weight %, more often less than about 30 dry weight %, or less than about 25 dry weight %.

[0063] In addition to the above components, the combustible fuel element of the present invention can incorporate a tobacco component (e.g., powdered tobacco or tobacco extract); a flavorant; or an ammonia source such as an ammonium salt. These types of components are typically used in an amount of less than about 10 dry weight %, often less than about 5 dry weight %, based on the dry weight of the fuel element.

[0064] The various components of the fuel element composition can be contacted, combined, or mixed together in a conical blender, mixing drum, ribbon blender, such as a Hobart mixer. Thus, the entire mixture of the various components may, in some embodiments, have a relatively uniform nature. In particular, it is advantageous for the ignition aid to be substantially uniformly dispersed throughout the fuel element composition. During mixing, the fuel element composition is typically in the form of a wet, dough-like paste. Thereafter, the fuel element can be formed into a desired shape by techniques such as compression, pressing, or extrusion. For example, the composition can be extruded using a single-screw or twin-screw extruder. Exemplary types of extrusion devices include those available as the ICMA San Giorgio model number 70-16D or the Welding Engineers model number 70-16LD. In the case of an extruded fuel element containing a relatively high level of carbonaceous material, the density of this fuel element can be slightly reduced by increasing the moisture level within the extruded mixture, by reducing the die pressure within the extruder, or by incorporating a relatively low-density material within the extruded mixture.

[0065] Alternatively, the fuel element can be formed using a foaming method of the type disclosed in U.S. Patent Application Publication No. 2008 / 0233294 to Lobovsky, which is incorporated herein by reference, as a primary carbonaceous material such as a carbon monolith, using a foamed carbon monolith structure. Various additional components, such as an ignition aid, can be incorporated into the monolith structure using known techniques such as spray coating or dip coating the monolith structure.

[0066] A representative fuel element has, for example, a length of about 12 mm and an overall outer diameter of about 4.2 mm. A representative fuel element can be extruded or compounded using a pulverized or powdered carbonaceous material and, on a dry weight basis, is about 0.5 g / cm 3 super, often about 0.7 g / cm 3Ultra, and in most cases, about 1 g / cm 3 has a density that is ultra. For example, U.S. Patent No. 4,714,082 to Banerjee et al., U.S. Patent No. 4,756,318 to Clearman et al., U.S. Patent No. 4,881,556 to Clearman et al., U.S. Patent No. 4,989,619 to Clearman et al., U.S. Patent No. 5,020,548 to Farrier et al., U.S. Patent No. 5,027,837 to Clearman et al., U.S. Patent No. 5,067,499 to Banerjee et al., U.S. Patent No. 5,076,297 to Farrier et al., U.S. Patent No. 5,099,861 to Clearman et al., U.S. Patent No. 5,105,831 to Banerjee et al., U.S. Patent No. 5,129,409 to White et al., U.S. Patent No. 5,148,821 to Best et al., U.S. Patent No. 5,156,170 to Clearman et al., U.S. Patent No. 5,178,167 to Riggs et al., U.S. Patent No. 5,211,684 to Shannon et al., U.S. Patent No. 5,247,947 to Clearman et al., U.S. Patent No. 5,345,955 to Clearman et al., U.S. Patent No. 5,461,879 to Barnes et al., U.S. Patent No. 5,469,871 to Barnes et al., U.S. Patent No. 5,551,451 to Riggs, U.S. Patent No. 5,560,376 to Meiring et al., U.S. Patent No. 5,706,834 to Meiring et al., U.S. Patent No. 5,727,571 to Meiring et al., U.S. Patent No. 7,836,897 to Borschke et al., U.S. Patent No. 8,469,035 to Banerjee et al., and U.S. Patent Application Publication No. 2005 / 0274390 to Banerjee et al., No. 2007 / 0215167 to Crooks et al., No. 2007 / 0215168 to Banerjee et al., No. 2012 / 0042885 to Stone et al., No. 2013 / 0269720 to Stone et al., and U.S. Application No. 14 / 036,536 to Conner et al. filed on September 25, 2013, which are incorporated herein by reference, are referred to for the types of fuel cells, representative components, this design and configuration, and the manner and method of generating these fuel cells, and this component.

[0067] The fuel elements prepared by the method of the present invention can be used in various smoking articles, such as any of the smoking articles described in US2007 / 0215167 to Crooks or US2007 / 0215168 to Banerjee, which are incorporated herein by reference. Exemplary smoking article structures can include a fibrous filter element, features such as a foamed ceramic monolith formed as a heat insulator, and other features disclosed in both U.S. Patent No. 8,464,726 to Sebastian et al. and U.S. Patent Publication No. 2013 / 0233329, which are incorporated herein by reference. Representative types of smoking articles in which the fuel elements of the present invention can be used are described in FIGS. 1 to 6. The fuel element is referred to as a heat source in the accompanying drawings and forms part of the heat generating segment of the smoking article.

[0068] FIG. 1 illustrates a representative smoking article 10 in the form of a cigarette. The smoking article 10 has a rod-like shape and includes a lit end 14 and a mouth end 18. At the lit end 14, a generally cylindrical heat generating segment 35 extending longitudinally is disposed. The heat generating segment 35 includes a heat source 40 surrounded by a heat insulator 42, and the heat insulator 42 can be coaxially surrounded by a wrapper material 45. The heat source 40 is preferably configured to be activated by direct ignition of the lit end 14. The smoking article 10 also includes a filter segment 65 located at the other end (mouth end 18) and an aerosol generating segment 51 (which may incorporate tobacco) located between two such segments.

[0069] Another embodiment of the fuel element 40 may include a foamed carbon monolith formed in the foaming process. In another embodiment, the fuel element 40 is coextruded with a layer of insulation 42, thereby reducing manufacturing time and cost. Still other embodiments of the fuel element can include those of the type described in U.S. Patent No. 4,819,655 to Roberts or U.S. Patent Application Publication No. 2009 / 0044818 to Takeuchi, each of which is incorporated herein by reference.

[0070] A representative layer of the insulation 42 can include glass filaments or fibers. The insulation 42 can act as a jacket that assists in firmly maintaining the heat source 40 in a predetermined position within the smoking article 10. The insulation 42 can be provided as a multi-layer component including an inner layer or mat of non-woven glass filaments, an intermediate layer of reconstituted tobacco paper, and an outer layer of non-woven glass filaments. These can be oriented in the same circumferential direction, or each can wrap around and / or surround the heat source from above. Various other embodiments of the insulation can be formed by molding, extrusion, foaming, or other methods. Particular embodiments of the insulation structure can include those described in U.S. Patent Application Publication No. 2012 / 0042885 to Stone, which is incorporated herein by reference in its entirety.

[0071] Preferably, both ends of the heat generating segment 35 are open at the ignition end 14 to expose at least the heat source 40 and the heat insulating material 42. The heat source 40 and the surrounding heat insulating material 42 can be configured such that the lengths of both materials are coextensive (i.e., both ends of the heat insulating material 42 exactly overlap the individual ends of the heat source 40, particularly at the downstream end of the heat generating segment). Optionally, although not necessarily preferably, the heat insulating material 42 may extend slightly beyond one or both ends of the heat source 40 (e.g., from about 0.5 mm to more than about 2 mm). Further, the heat and / or heated air generated when the ignition end 14 is ignited during use of the smoking article 10 can easily pass through the heat generating segment 35 while being inhaled by the smoker at the mouth end 18.

[0072] The heat generating segment 35 is preferably located at one end disposed at the ignition end 14 and is axially aligned in an end-to-end relationship with the downstream aerosol generating segment 51, and is preferably adjacent to each other, but there is no barrier (other than the open air space) between them. When the heat generating segment 35 approaches the ignition end 14, direct ignition of the heat source / fuel element 40 of the heat generating segment 35 is caused.

[0073] The cross-sectional shape and dimensions of the heat generating segment 35 before combustion can be various. Preferably, the cross-sectional area of the heat source 40 constitutes about 10% to about 35%, often about 15% to about 25% of the total cross-sectional area of this segment 35, while the cross-sectional area of the outer or peripheral region (including the heat insulating material 42 and the associated outer wrapping material) constitutes about 65% to about 90%, often about 75% to about 85% of the total cross-section of this segment 35. For example, in the case of a cylindrical smoking article having a circumference of about 24 mm to about 26 mm, a typical heat source 40 generally has an outer diameter of about 2.5 mm to about 5 mm, often about 3 mm to about 4.5 mm, and has a substantially circular cross-sectional shape.

[0074] The cylindrical aerosol generating segment 51, which extends in the longitudinal direction, is located downstream of the heat generating segment 35. The aerosol generating segment 51 includes a base material 55, which serves as a carrier for an aerosol forming agent or material (not shown). For example, the aerosol generating segment 51 can include a reconstituted tobacco material that includes processing aids, flavorants, and glycerin. The above-described components of the aerosol generating segment 51 can be disposed inside and surrounded by a wrapping material. The wrapping material can be configured to facilitate the propagation of heat from the ignition end 14 of the smoking article 10 (e.g., from the heat generating segment 35) to the components of the aerosol generating segment 51. That is, the aerosol generating segment 51 and the heat generating segment 35 can be configured in a heat exchange relationship with each other. This heat exchange relationship is such that sufficient heat from the heat source 40 is supplied to the aerosol forming region to volatilize the aerosol forming material for aerosol formation. In some embodiments, the heat exchange relationship is achieved by arranging these segments in close proximity to each other. The heat exchange relationship can also be realized by extending a thermally conductive material from the vicinity of the heat source 40 into or around the region occupied by the aerosol generating segment 51. Specific embodiments of the base material can include those described below, or those described in U.S. Patent Application Publication No. 2012 / 0042885 to Stone et al., which is hereby incorporated by reference in its entirety.

[0075] Typical wrapping materials for the base material 55 can include heat conduction characteristics that conduct heat from the heat generating segment 35 to the aerosol generating segment 51 to cause volatilization of the aerosol forming components contained therein. The base material 55 can have a length of from about 10 mm to about 22 mm, and in certain embodiments is from about 11 mm to a maximum of about 21 mm. The base material 55 can be supplied from a blend of flavored and aromatic tobacco in the form of cut filler. These tobaccos can be treated with aerosol forming materials and / or at least one flavorant. The base material can be supplied from processed tobacco in the form of cut filler (e.g., reconstituted tobacco manufactured using a cast sheet or paper type process). Certain cast sheet structures can include from about 270 to about 300 mg of tobacco per 10 mm of straight length. This tobacco can, in turn, be treated with or incorporated with an aerosol forming material and / or at least one flavorant, and a burn retardant (e.g., diammonium phosphate or another salt) configured to assist in preventing ignition and / or scorching by the heat generating segment. The metallic inner surface of the wrapping material of the aerosol generating segment 51 can serve as a carrier for the aerosol forming material and / or at least one flavorant.

[0076] In other embodiments, the substrate 55 can include cigarette paper or non-cigarette collection paper formed as a plug area. The plug area can be loaded with aerosol-forming materials, flavorings, tobacco extracts, etc. in various forms (e.g., microencapsulated, liquid, powdered). A combustion retardant (e.g., diammonium phosphate or another salt) can be applied to at least the distal end / ignition end portion of the substrate to assist in preventing ignition and / or burning by the heat-generating segment. In these and / or other embodiments, the substrate 55 can include pellets or beads formed from marumarized and / or non-marumarized tobacco. Marumarized tobacco is known, for example, from U.S. Patent No. 5,105,831 to Banerjee et al., which is incorporated herein by reference. Marumarized tobacco can include, along with a binder and flavorant, for example, a tobacco blend in powder form of about 20 to about 50% (by weight), glycerol (about 20 to about 30% by weight), calcium carbonate (generally about 10 to about 60% by weight, often about 40 to about 60% by weight). The binder can include, for example, carboxymethyl cellulose (CMC), gums (e.g., guar gum), xanthan, pullulan, and / or alginate. The beads, pellets, or other marumarized forms can be constructed in dimensions suitable to fit snugly within the substrate area and to provide an optimal air flow and desired aerosol generation. Containers such as cavities or capsules can be formed to hold the substrate in a predetermined position within the smoking article. Such containers can be beneficial for containing pellets or beads made of, for example, marumarized and / or non-marumarized tobacco. The containers can be formed using wrapping materials as further described below.

[0077] As described above, the aerosol generating segment 51 can include an aerosol generating material or element that can be defined as other individual small units of beads, pellets or compositions, usually including tobacco or some of its components (e.g., tobacco that has been marumerized and / or not marumerized). Such pellets may have a smooth regular outer shape (e.g., spherical, cylindrical, oval, etc.) and / or an irregular outer shape. In one example, the diameter of each pellet can range from about 1 mm to less than about 2 mm. The pellets can fill at least a part of the substrate cavity of the smoking article described herein. In one example, the volume of the substrate cavity can range from about 500 mm 3 to about 700 mm 3 (e.g., the substrate cavity of the smoking article, where the diameter of the cavity is from about 7.5 to about 7.8 mm, the length of the cavity is from about 11 to about 15 mm, and the cavity generally has a cylindrical shape). In one example, the mass of the pellets inside the substrate cavity can range from about 200 mg to about 500 mg.

[0078] Generally, as used herein, the terms "pellet" and "bead" are intended to include beads, pellets, or other discrete small units, and these small pieces (especially in addition to those disclosed herein) can include, for example, carbon pieces, extruded carbon pieces cut into pellets, ceramic beads, marumerized tobacco pieces, etc., or combinations thereof. For example, granules, pellets, or beads can be formed from a wet mixture or slurry consisting of milled tobacco flakes, fillers (e.g., granular calcium carbonate), flavors, visible aerosol-forming materials, and binders (e.g., carboxymethyl cellulose) that are formed into, cut into, or spun into a desired size and shape and then dried to retain the desired configuration, and made into substantially cylindrical or spherical extruded or compressed granules, pellets, or beads. For example, some or all of the beads or pellets can include highly heat-sensitive spherical capsules, such that when contained in an aerosol-generating element and exposed to heat, their destruction or decomposition causes the release of glycerin, propylene glycol, water, physiological saline, tobacco flavor and / or nicotine, or other substances or additives. Similarly, the beads can include ceramic, or absorbent clay or silica, or absorbent carbon to hold and release the aerosol-forming composition. Further, in some embodiments, the beads / pellets can include thermally conductive materials such as thermally conductive graphite, thermally conductive ceramic, metal, tobacco cast on foil, metal or other suitable materials impregnated with suitable aerosol-generating substances such as glycerin and flavors, or suitable cast sheet materials appropriately formed into the desired beads / pellets.

[0079] In one specific example, the beads / pellets (particles) can be composed, on a weight basis, of from about 15% to about 60% finely milled tobacco particles (e.g., a blend of Oriental, Burley, and Virginia tobacco, substantially all Oriental tobacco, substantially all Burley tobacco, or substantially all Virginia tobacco), from about 15% to about 60% finely milled calcium carbonate particles (or finely milled clay or ceramic particles), from about 10% to about 50% glycerol (and optionally a small amount of flavor), from about 0.25% to about 15% binder (preferably carboxymethylcellulose, guar gum, potassium alginate or ammonium alginate), and from about 15% to about 50% water. In another example, the beads / pellets (particles) can be composed of about 30% finely milled tobacco particles (e.g., a blend of Oriental, Burley, and Virginia tobacco, substantially all Oriental tobacco, substantially all Burley tobacco, or substantially all Virginia tobacco), about 30% finely milled calcium carbonate particles (or finely milled clay or ceramic particles), about 15% glycerol (and optionally a small amount of flavor), about 1% binder (preferably carboxymethylcellulose, guar gum, potassium alginate or ammonium alginate), and about 25% water.

[0080] In such examples, the pellets may be compressed to hold glycerol and, upon compression, form a porous matrix that facilitates the movement of aerosol generating components that promote efficient aerosol formation. The manner in which the aerosol forming material contacts the substrate material can vary. The aerosol forming material can be applied to the formed material, incorporated into the processed material during the manufacture of these materials, or can become endogenous to such materials. An aerosol forming material such as glycerol can be dissolved or dispersed in an aqueous liquid, or other suitable solvent or liquid carrier and sprayed onto the substrate material. See, for example, U.S. Patent Application Publication Nos. 2005 / 0066986 to Nestor et al. and 2012 / 0067360 to Conner et al., which are incorporated herein by reference. Calcium carbonate or other inorganic fillers can also assist in creating porosity within the particles and function to absorb heat, thereby, in some examples, limiting or otherwise preventing burning of the aerosol generating components and assisting and promoting aerosol formation. See also such types of materials described in U.S. Patent No. 5,105,831 to Banerjee et al. and U.S. Patent Application Publication Nos. 2004 / 0173229 to Crooks et al., 2011 / 0271971 to Conner et al., and 2012 / 0042885 to Stone et al., which are incorporated herein by reference.

[0081] Components derived from tobacco in the form of beads or pellets can contain nicotine derived from highly purified tobacco (e.g., pharmaceutical grade nicotine having a purity of greater than 98% or greater than 99%), or derivatives thereof can be used in the present invention. Representative nicotine-containing extracts can be provided using the techniques described in U.S. Patent No. 5,159,942 to Brinkley et al., which is incorporated herein by reference. In certain embodiments, the products of the present invention can contain any form of nicotine from any source, whether tobacco-derived or synthetic-derived. The nicotine compounds used in the products of the present invention can include nicotine in free base form, salt form, as a complex or as a solvate. See, for example, the discussion of nicotine in free base form in U.S. Patent Publication No. 2004 / 0191322 to Hansson, which is incorporated herein by reference. At least a portion of the nicotine compound can be used in the form of a resin complex of nicotine, in which case the nicotine is bound to an ion exchange resin such as nicotine polacrillex. See, for example, U.S. Patent No. 3,901,248 to Lichtneckert et al., which is incorporated herein by reference. At least a portion of the nicotine can be used in salt form. Salts of nicotine can be provided using the types of components and techniques described in U.S. Patent No. 2,033,909 to Cox et al. and Perfetti, Beitrage Tabakforschung Int., Vol. 12, pp. 43-54 (1983). Further, salts of nicotine are available from suppliers such as Pfaltz and Bauer, Inc. and K&K Laboratories, Division of ICN Biochemicals, Inc.Exemplary pharmaceutically acceptable nicotine salts include nicotine salts of tartrate ions (e.g., nicotine tartrate and nicotine hydrogen tartrate), chlorides (e.g., nicotine hydrochloride and nicotine dihydrochloride), sulfates, perchlorates, ascorbates, fumarates, citrates, malates, lactates, aspartates, salicylates, tosylates, succinates, pyruvates, etc.; nicotine salt hydrates (e.g., nicotine zinc chloride monohydrate), etc. In certain embodiments, at least a portion of the nicotine compound is in the form of a salt with an organic acid moiety, including but not limited to levulinic acid, discussed in U.S. Patent Publication No. 2011 / 0268809 to Brinkley et al., which is incorporated herein by reference.

[0082] In one embodiment, an aerosol-generating material discussed herein, such as in the form of beads or pellets, can be smoked to impart a smoky flavor or aroma. For example, beads or pellets can be prepared and then subjected to smoke from a combustible source such as wood (e.g., wood selected from hickory, maple, oak, apple, cherry, or mesquite). The beads or pellets can be treated with smoke for a time sufficient to impart the desired smoky flavor or aroma, and an exemplary time range is from about 5 to about 45 minutes. The method by which the beads or pellets are contacted with the smoke can vary, and one example includes heating wood chips in a container (e.g., heating the wood chips to a temperature of about 350 - 400°F) until smoke is generated and placing the beads or pellets to be treated in a sealed environment containing the smoke generated by the wood chips.

[0083] In yet other embodiments, the substrate 55 can be configured as a formed monolithic substrate, for example, as described in U.S. Patent Application Publication No. 2012 / 0042885 to Stone et al., which is hereby incorporated by reference in its entirety. The substrate can include, or be constructed from, an extruded material. The substrate may also be formed by press fitting or molding / casting. Thus, the general term "monolithic substrate" can include substrates formed by extrusion or by one of such other methods.

[0084] In some preferred smoking articles, both ends of the aerosol generating segment 51 are open to expose to this substrate material 55. Overall, the heat generating segment 35 and the aerosol generating segment 51 form an aerosol generating system. The aerosol generating segment 51 is disposed adjacent to the downstream end of the heat generating segment 35 such that such segments 51, 35 are axially aligned in an end-to-end relationship. These segments can be in contact with each other or can include a buffer region 53 and are disposed in a slightly spaced-apart relationship. The outer cross-sectional shape and dimensions of these segments can be essentially the same as each other when viewed across the longitudinal axis of the smoking article 10. The physical arrangement of these components is preferably such that heat is transferred (e.g., by means including conductive and convective heat transfer) from the heat source 40 to the adjacent substrate material 55 throughout the time the heat source is activated (e.g., combusted) during use of the smoking article 10.

[0085] The buffer region 53 can reduce some potential burning or other thermal decomposition of the aerosol generation segment 51. The buffer region 53 can mainly contain an empty air space, or this buffer region may be filled with some or substantially all of a non-combustible material such as, for example, a metal, organic, inorganic, ceramic or polymer material, or any combination thereof. The buffer region can have a thickness (length) of from about 1 mm to about 10 mm or more, but often has a thickness (length) of from about 2 mm to about 5 mm.

[0086] The components of the aerosol generation system are preferably attached to each other and fixed in place using an overwrap material 64. For example, the overwrap material 64 can include a paper wrapping material or a laminated paper type material, and these materials surround at least a part of the outer longitudinal surfaces extending outside each of the heat generation segments 35 and the aerosol generation segment 51. The inner surface of the overwrap material 64 can be fixed to the outer surface of the surrounded components by a suitable adhesive.

[0087] The smoking article 10 preferably includes a suitable mouthpiece, such as, for example, filter element 65 disposed at this mouth end 18. Filter element 65 is preferably disposed at one end of a cigarette rod adjacent to one end of aerosol generating segment 51 such that filter element 65 and aerosol generating segment 51 are axially aligned end-to-end and adjacent to each other with no barrier therebetween. Preferably, when viewed transversely to the longitudinal axis of the smoking article, the general cross-sectional shape and dimensions of these segments 51, 65 are essentially identical to each other. Filter element 65 can include a filter material wrapped around the plugwrap material along this longitudinally extending surface. In one example, the filter material includes plasticized cellulose acetate tow, while in some examples, the filter material may further include from about 20 to about 80 mg of activated carbon disposed or dispersed as an individual filling throughout the acetate tow in a “Dulcian type” filter. Both ends of filter element 65 are preferably open to allow passage of aerosol therethrough. The aerosol generating system is preferably attached to filter element 65 using tipping material 78. The smoking article 10 can include air dilution means, such as a series of perforations 81, each of which may extend from filter element tipping material 78 and plugwrap material in the manner shown, and / or the above perforations may extend to substrate 55 or into substrate 55.

[0088] The filter element 65 may also include crushable flavor capsules of the type described in U.S. Patent No. 7,479,098 to Thomas, U.S. Patent No. 7,793,665 to Dube, and U.S. Patent No. 8,186,359 to Ademe, which are hereby incorporated by reference in their entirety. The filter may include, for example, materials such as those disclosed in U.S. Patent No. 7,740,019 to Nelson, U.S. Patent No. 7,972,254 to Stokes, U.S. Patent No. 8,375,958 to Hutchens, and U.S. Patent Publication No. 2008 / 0142028 to Fagg and U.S. Patent Publication No. 2009 / 0090372 to Thomas, each of which is hereby incorporated by reference in its entirety, and may be manufactured by methods such as those disclosed above.

[0089] The overall dimensions of the smoking article 10 prior to combustion can vary. Typically, the smoking article 10 is a cylindrical rod having a circumference of from about 20 mm to about 27 mm and an overall length of from about 70 mm to about 130 mm, and often from about 83 mm to about 100 mm. The aerosol generating system can have an overall length that can vary from about 20 mm to about 65 mm. The heat generating segment 35 of the aerosol generating system can have a length of from about 5 mm to about 30 mm. The aerosol generating segment 51 of the aerosol generating system can have an overall length of from about 10 mm to about 60 mm.

[0090] The combined amount of aerosol forming agent and base material 55 used in the aerosol generating segment 51 can vary. The materials can preferably be used to fill a suitable area (e.g., the area within this wrapping material) of the aerosol generating segment 51 at a packing density of from about 100 to about 400 mg / cm 3 of.

[0091] In use, the smoker ignites the ignition end 14 of the smoking article 10 using a match or cigarette lighter in the same manner as a conventional smoking article is ignited such that the heat source / fuel element 40 at the ignition end 14 is ignited. The mouth end 18 of the smoking article 10 is placed against the smoker's lips. The pyrolysis products (e.g., components of tobacco smoke) generated by the aerosol generation system are drawn through the filter element 65 and into the smoker's oral cavity through the smoking article 10. That is, the smoking article produces a visible mainstream aerosol that resembles the mainstream smoke of tobacco in a traditional cigarette that burns a shredded tobacco filler when smoked.

[0092] Direct ignition actuates the fuel element 40 of the heat generating segment 35 such that the fuel element 40 of the heat generating segment 35 is ignited or otherwise activated (e.g., begins to burn). The heat source 40 within the aerosol generation system burns, resulting in heat that volatilizes the aerosol forming material within the aerosol generation segment 51 due to the heat exchange relationship between these two segments. Certain preferred heat sources 40 do not undergo a reduction in volume during activation, while others may decompose to reduce this volume. Preferably, the components of the aerosol generation segment 51 do not undergo any significant degree of pyrolysis (e.g., carbonization or combustion), and the volatile components are carried suspended in the air drawn through the aerosol generation region 51. The aerosol thus formed is drawn through the filter element 65 and into the smoker's oral cavity.

[0093] During a period of use, the aerosol formed within the aerosol generation segment 51 is drawn through the filter element 65 and into the smoker's oral cavity. Thus, the mainstream aerosol produced by the smoking article 10 contains tobacco smoke produced by the volatilized aerosol forming material.

[0094] The flavor may be provided or enhanced by a capsule or microcapsule material on or within the base material 55, wrapping material, filter element 65 or any other component of the aerosol generating segment 51 that can hold and release the flavoring while minimizing pyrolysis which results in undesirable modification of the flavor. Other flavor components associated with the filter may also be used. See, for example, U.S. Patent No. 5,724,997 to Fagg et al.

[0095] As described above, the fuel element is preferably surrounded or otherwise covered from above by a heat insulating material or other suitable material. The heat insulating material can be configured and used to support, maintain, and hold the fuel element in a predetermined position within the smoking article. The heat insulating material can be further configured such that the drawn air and aerosol can easily pass through the heat insulating material. Examples of heat insulating materials within the heat generating segment, components of the heat insulating assembly, configurations of representative heat insulating assemblies, wrapper materials for the heat insulating assembly, and the manner and method of producing these components and assemblies are incorporated herein by reference in U.S. Patent No. 4,807,809 to Pryor et al., U.S. Patent No. 4,893,637 to Hancock et al., U.S. Patent No. 4,938,238 to Barnes et al., U.S. Patent No. 5,027,836 to Shannon et al., U.S. Patent No. 5,065,776 to Lawson et al., U.S. Patent No. 5,105,838 to White et al., U.S. Patent No. 5,119,837 to Banerjee et al., U.S. Patent No. 5,247,947 to Clearman et al., U.S. Patent No. 5,303,720 to Banerjee et al., U.S. Patent No. 5,345,955 to Clearman et al., U.S. Patent No. 5,396,911 to Casey III et al., U.S. Patent No. 5,546,965 to White, U.S. Patent No. 5,727,571 to Meiring et al., U.S. Patent No. 5,902,431 to Wilkinson et al., U.S. Patent No. 5,944,025 to Cook et al., U.S. Patent No. 8,424,538 to Thomas et al., and U.S. Patent No. 8,464,726 to Sebastian et al. The heat insulating assembly is incorporated into cigarette types marketed under the trade names "Premier" and "Eclipse" by the R.J. Reynolds Tobacco Company and as "Steam Hot One" by Japan Tobacco Inc.

[0096] Flame retardant / combustion retardant substances and additives useful in heat insulating materials can include silica, carbon, ceramics, metal fibers and / or particles. For example, when being processed, cellulose fibers or other fibers such as cotton, boric acid or various organic phosphate compounds can bring about desirable flame retardant properties. Further, various organic nanoparticles or metal nanoparticles can impart the desired property of flame retardancy, similar to diammonium phosphate and / or other salts. Other useful substances can include organic phosphorus compounds, borax, hydrated alumina, graphite, potassium tripolyphosphate, dipentaerythritol, pentaerythritol and polyols. Other ones such as nitrogenous phosphonates, monoammonium phosphate, ammonium polyphosphate, ammonium bromide, ammonium chloride, ammonium borate, ammonium ethanol borate, ammonium sulfamate, halogenated organic compounds, thiourea and antimony oxide can be used, but are not preferred agents. In each embodiment (regardless of whether alone, or in any combination with each other and / or with other materials) of the flame retardant substances, combustion retardant substances and / or charring retardant substances used in heat insulating materials, base materials and other components, the desired properties are most preferably those brought about without undesirable off-gas or dissolution-type behavior.

[0097] The heat insulating cloth preferably has an oxygen diffusion capacity sufficient to keep a smoking article such as a cigarette in a burning state during a desired use time. Thus, the heat insulating cloth preferably has porosity for the advantages of this structure. In knitting, weaving, or a combined structure of weaving and knitting, the necessary pores can be controlled by configuring an assembling machine so as to leave sufficient (desirably sized) gaps between fibers to enable oxygen diffusion into the heat source. Regarding non-woven fabrics that cannot be porous enough to promote uniformly sustained combustion, additional pores can be achieved by perforating the heat insulating material by methods known in the art, including, for example, high-temperature or low-temperature pin punching, flame punching, embossing, laser cutting, drill punching, blade cutting, chemical punching, punching, and other methods. The buffer material and the heat insulating material can each include a non-glass material, a foamed metal material, a foamed ceramic material, a foamed ceramic-metal composite, and any combination thereof that is woven, knitted, or a combination of these. The material in the heat insulating material may be the same as or different from that in the buffer material.

[0098] The aerosol-forming material can be various, and mixtures of various aerosol-forming materials can be used, as can various combinations and various flavoring agents (including various materials that modify the sensory and / or sensory acceptance characteristics or properties of the mainstream aerosol of the smoking article), wrapping materials, mouth-side end pieces, filter elements, plug wraps, and tipping materials. Representative types of these components are described in U.S. Patent Application Publication No. 2007 / 0215167 to Llewellyn Crooks et al., which is hereby incorporated by reference in its entirety.

[0099] The substrate material can incorporate some forms of tobacco and is typically composed mainly of tobacco and can be substantially supplied by all of the tobacco material. The form of the substrate material can be various. In some embodiments, the substrate material is essentially used in the form of a traditional filler (e.g., as cut filler). Otherwise, the substrate material can be formed into the desired composition (see, e.g., U.S. Patent Publication No. 2011 / 0271971 to Conner et al., which is incorporated herein by reference). The substrate material can be used in the form of a collecting web or sheet using techniques generally described in U.S. Patent No. 4,807,809 to Pryor et al., which is incorporated herein by reference in its entirety. The substrate material can be used in the form of a web or sheet that is scored and made into a plurality of longitudinally extending bundles using techniques generally described in U.S. Patent No. 5,025,814 to Raker, which is incorporated herein by reference in its entirety. The substrate material can have the form of a loosely wound sheet such that a helical air flow path extends longitudinally through the aerosol generating segment. Representative types of tobacco containing the substrate material can be manufactured from a mixture of tobacco types or from one main type of tobacco (e.g., a cast sheet type or paper type of reconstituted tobacco mainly composed of burley tobacco, or a cast sheet type or paper type of reconstituted tobacco mainly composed of oriental tobacco).

[0100] The substrate material can also be treated with tobacco additives of the types traditionally used in the manufacture of cigarettes, such as casing and / or top dressing components. See, for example, the types of components described in U.S. Patent Publication No. 2004 / 0173229 to Crooks et al., which is incorporated herein by reference in its entirety.

[0101] The manner in which the aerosol-forming material contacts the substrate material (e.g., tobacco material) can be various. The aerosol-forming material can be applied to the formed tobacco material or incorporated into the processed tobacco material during the manufacture of these materials. The aerosol-forming material can be dissolved or dispersed in an aqueous liquid or other suitable solvent or liquid carrier and sprayed onto the substrate material described above. See, for example, U.S. Patent Application Publication No. 2005 / 0066986 to Nestor et al., which is hereby incorporated by reference in its entirety. The amount of aerosol-forming material used relative to the dry weight of the substrate material can vary. Using a conventional type of automatic cigarette manufacturing apparatus, it may be difficult to process a material containing a very high level of aerosol-forming material into a cigarette rod.

[0102] Cast sheet type materials can incorporate a relatively high level of aerosol-forming material. Reconstituted tobacco manufactured using a papermaking type process can incorporate a medium level of aerosol-forming material. Tobacco strips and cut filler tobacco can incorporate a lesser amount of aerosol-forming material. A variety of paper and non-paper substrates, including collected, laminated, metal / metal laminated strips, beads such as alumina beads, open-cell foams, foam monoliths, air-permeable matrices and other materials, can be used within the scope of the present disclosure. See, for example, U.S. Patent Nos. 5,183,062, 5,203,355 and 5,588,446 to Clearman, each of which is hereby incorporated by reference in its entirety.

[0103] In other embodiments, the substrate portion of the aerosol generating segment can include, or can be constructed from, an extruded material or other monolithic material. The extruded substrate can be formed in the same manner as described herein with reference to other extruded components. The extruded substrate or other monolithic substrate can include, or can consist essentially of, tobacco, glycerin, water, and a binder material. In certain embodiments, the monolithic substrate can include from about 10 to about 90 weight % tobacco, from about 5 to about 50 weight % glycerin, from about 1 to about 30 weight % water (prior to drying and cutting), and from about 0 to about 10 weight % binder. The monolithic substrate can also include fillers such as, for example, calcium carbonate and / or graphite.

[0104] After extrusion, drying, and cutting to the desired length, the substrate can be assembled into a segmented smoking article such as an Eclipse-type cigarette using a manual assembly method or a cigarette making machine (e.g., KDF or Protus by Hauni Maschinenbau AG). Smaller diameter monolithic substrate elements can be combined together by being packaged, adhered, or otherwise assembled together for use in the smoking articles described herein for other substrate embodiments. Preferred substrate wraps include foil paper, heavy paper, plug wrap, and / or cigarette paper.

[0105] The cigarette described with reference to FIG. 1 can be used in much the same manner as such cigarettes marketed under the trademark "Eclipse" by the R.J. Reynolds Tobacco Company. Reference is also made to the "Steam Hot One" cigarette marketed by Japan Tobacco Inc.

[0106] In one embodiment, with reference to FIG. 2 which is a longitudinal cross-sectional view of a cigarette 410 having a lit end 414 and a mouth end 418, the monolithic substrate 463 described herein can be constructed. The monolithic substrate 463 (which can be used in other embodiments, such as those discussed with reference to FIG. 1) can be formed by any suitable extrusion method and is shown with a central bore 495 extending longitudinally within the monolithic substrate. The monolithic substrate cut to length can constitute from about 1 / 16 to about 5 / 8 of the total length of the cigarette, and often from about 1 / 10 to about 1 / 2 (e.g., for an 85 mm or 130 mm long cigarette, a substrate element 10 mm, 12 mm or 50 mm in length). The substrate segment 455 of the cigarette body includes a hollow spacer tube 467 disposed between the substrate 463 and the filter 470. The filter 470 is shown as being constructed of a covering layer consisting of a plug wrap 472 and tipping paper 478. The substrate 463 and the tube 467 are surrounded by a wrapping material 458 that can be configured, for example, as a thermally conductive material (e.g., foil paper), thick paper, plug wrap or cigarette paper. A cylindrically surrounding wrapping material 464 (such as cigarette paper or thick paper) can be provided to connect the heat generating segment 435, the central substrate segment 455 and the filter segment 465. The heat generating segment 435 and other components can be constructed as described in this embodiment and other parts of this and other embodiments as implemented within the scope of this specification and this disclosure.

[0107] In another embodiment, a smoking article can be constructed using the elongated monolithic substrate 563 described herein with reference to FIG. 3, which is a longitudinal cross-sectional view of a cigarette 510 having a lit end 514 and a mouth end 518. The elongated monolithic substrate 563 (which may be used in other embodiments) can be formed by any suitable extrusion process and is shown with a central bore 595 extending longitudinally within the monolithic substrate. The filter 570 is shown as being constructed of a wrapper layer consisting of a plug wrap 572 and tipping paper 578. The substrate 563 is surrounded by a wrapping material 558 that can be configured, for example, as a thermally conductive material (e.g., foil paper), heavy paper, plug wrap, or cigarette paper. A cylindrically surrounding wrapping material 564 (such as cigarette paper or heavy paper) can be provided to connect the heat generating segment 535, the central substrate segment 555 (which consists essentially of the substrate in this embodiment), and the filter segment 565. The heat generating segment 535 and other components can be constructed as described in this and other parts of this embodiment and other embodiments, as configured to be practiced within the scope of this specification and this disclosure.

[0108] In one embodiment, with reference to FIG. 4 which is a longitudinal sectional view of a cigarette 610 having a lit end 614 and a mouth end 618, a monolithic substrate 663 described herein can be used to construct the smoking article. The monolithic substrate 663 (which may also be used in other embodiments) can be formed by any suitable extrusion method and is shown here with a central bore 695 extending longitudinally therefrom. The cigarette body includes a tobacco rod 669 disposed between the substrate 663 and the filter 670. The filter 670 is shown as being constructed of a wrapper layer consisting of plug wrap 672 and tipping paper 678. The substrate segment 655 formed by the substrate 663 and the tobacco rod 669 is surrounded by a wrapping material 658 that can be configured, for example, as a thermally conductive material (e.g., foil paper), thick paper, plug wrap, or cigarette paper. A cylindrically surrounding wrapping material 664 (such as cigarette paper or thick paper) can be provided to connect the heat generating segment 635, the central substrate segment 655, and the filter segment 665. The heat generating segment 635 and the other components can be constructed as described in this and other parts of this embodiment and other embodiments as configured to be implemented within the scope of this specification and this disclosure.

[0109] In another embodiment, with reference to FIG. 5 which is a longitudinal sectional view of a cigarette 710 having a lit end 714 and a mouth end 718, a substrate 763 in the form of the above-described beads or pellets described herein can be used to construct the smoking article. The substrate 763 (which may also be used in other embodiments) can be formed by any suitable method such as the above-described marumerizer treatment method. The cigarette body includes a tobacco rod 769 disposed between the substrate 763 and the filter 770. The filter 770 is shown as being constructed of a wrapper layer consisting of plug wrap 772 and tipping paper 778. The heat generating segment 735 and the other components can be constructed as described in this and other parts of this embodiment and other embodiments as configured to be implemented within the scope of this specification and this disclosure.

[0110] The substrate 763 can be contained within the substrate cavity 756 (see, e.g., U.S. Patent Publication No. 2012 / 0067360 to Conner et al., which is incorporated herein by reference). The substrate cavity 756 can be formed by a heat generating segment 735 at one end, a tobacco rod 769 at the opposite end, and a wrapper 764 at least around the perimeter of the substrate (and, in some embodiments, extending along the entire length from the filter to the ignition end). A cylindrical container structure (not shown) can circumferentially surround the wrapper 764 and the substrate cavity 756 between the heat generating segment 735 at one end and the tobacco rod 769 at the opposite end. The heat generating segment 735 and the tobacco rod 769 can be joined to each other by the wrapper 764. For this purpose, the wrapper 764 can surround at least the downstream portion of the heat generating segment 735 and at least the upstream portion of the tobacco rod 769. The heat generating segment 735 and the tobacco rod 769 can be longitudinally spaced from each other. In other words, the heat generating segment 735 and the tobacco rod 769 may not be in contact with and adjacent to each other. The substrate cavity 756 can be defined by a longitudinally extending space within the wrapper 764 between the downstream end of the heat generating segment 735 and the upstream end of the tobacco rod 769, as shown in FIG. 5. The substrate 763 may be disposed within the substrate cavity 756. For example, the substrate cavity 756 can be at least partially filled with tobacco pellets. The substrate cavity 756 may include the substrate 763 to prevent movement of the tobacco pellets.

[0111] The wrapping material 764 can be configured as, for example, a thermally conductive material (e.g., foil paper), a heat insulating material, thick paper, plug wrap, cigarette paper, tobacco paper, or any combination thereof. Further or alternatively, the wrapping material 764 can include foil, ceramic, ceramic paper, carbon felt, glass mat, or any combination thereof. Other wrapping materials known or developed in the art can be used alone or in combination with one or more of these wrapping materials. In one embodiment, the wrapping material 764 can include a paper material having strips or patches of foil laminated thereto. The wrapping material 764 may include a paper sheet 783. The paper sheet 783 can be sized and shaped to surround the heat generating segment 735, the substrate cavity 756, and the tobacco rod 769 as described above. For this purpose, the paper sheet 783 can have a substantially rectangular shape having a length extending along the longitudinal direction of the smoking article and a width extending in a direction transverse to the longitudinal direction. The width of the paper sheet 783 may be slightly larger than the circumference of the smoking article so that this paper sheet can be formed into a tube or columnar object that defines the outer surface of the smoking article 710. For example, the width of the paper sheet 783 can be from about 18 to about 29 mm. The length of the paper sheet 783 can extend longitudinally along the entire length of the substrate cavity 764 and be sufficient to overlap the heat generating segment 735 and the tobacco rod 769. For example, the length of the paper sheet 783 can be from about 50 to about 66 mm. The paper sheet 783 can have a length sufficient to substantially overlap the entire length of the tobacco rod 769 as shown in FIG. 5. In one example, the paper sheet (or other wrapping material) can have a thickness from about 1 mil to about 6 mils (about 0.025 mm to about 0.15 mm).

[0112] The foil strip or patch 784 can be laminated to the paper sheet 783 to form a laminated coating region. The foil strip 784 can have a width that extends along substantially the entire width of the paper sheet 783 so as to substantially surround the entire periphery of the heat generating segment 735, the base cavity 764, and the tobacco rod 769, as further described below. The foil strip 784 can also have a length that extends along a portion of the length of the paper sheet 783. Preferably, the foil strip 784 can extend along a sufficient portion of the length of the paper sheet 783 such that the foil strip extends along the entire length of the base cavity 756 and overlaps at least a portion of the heat generating segment 735 and the tobacco rod 769. For example, the length of the foil strip 784 can be from about 16 to about 20 mm. In one example, the foil strip can have a thickness from about 0.0005 mm to about 0.05 mm.

[0113] The intermediate segment of the smoking article can include a heat generating segment, a base segment (e.g., a monolithic base or a base cavity including pellets or beads of a base material), and a tobacco rod. It may be desirable to supply such an intermediate segment from a so-called "two-up" rod that can be handled using a conventional type or suitably modified cigarette rod processing apparatus such as a tipping apparatus available from Hauni-Werke Korber & Co. KG as Lab MAX, MAX, MAX S or MAX80. See, for example, U.S. Patent No. 3,308,600 to Erdmann et al., U.S. Patent No. 4,281,670 to Heitmann et al., U.S. Patent No. 4,280,187 to Reuland et al., U.S. Patent No. 4,850,301 to Greene, Jr. et al., U.S. Patent No. 6,229,115 to Vos, U.S. Patent No. 7,434,585 to Holmes and U.S. Patent No. 7,296,578 to Read, Jr., and U.S. Patent Application Publication No. 2006 / 0169295 to Draghetti, each of which is incorporated herein by reference.

[0114] For example, FIG. 6 illustrates a two-up rod that may be generated in the method of manufacturing the smoking article 710 of FIG. 5 or other smoking articles described herein. The two-up rod can include, as described above, two intermediate segments that are joined to each other in a common tobacco rod. The two-up rod can include two heat generating segments 835a, 835b disposed at these opposing longitudinal ends. The tobacco rod 869 can be substantially centered along the longitudinal axis of the rod. The tobacco rod 869 includes two parts 869a, 869b, each of which can be joined to one intermediate segment. The tobacco rod 869 and the two heat generating segments 835a, 835b can be joined to each other by the wrapper material 864 as described above with reference to FIG. 5. The substrate cavity 856a can be defined within the wrapper material 864 between the heat generating segment 835a and the tobacco rod 869. The substrate 863a can be contained within the substrate cavity 856a. Similarly, the substrate cavity 856b can be defined within the wrapper material 864 between the heat generating segment 835b and the tobacco rod 869. The substrate 863b can be contained within the substrate cavity 856b. The wrapper material 864 can include a paper sheet 883 having foil strips 884a, 884b laminated thereto. The foil strips can generally be aligned with the substrate cavities as described above with reference to FIG. 5. The rod can be divided at approximately the center of its longitudinal direction to form two intermediate segments, each generally configured as described above. The tobacco rod, hollow tube and / or filter element can be attached to the downstream end of each intermediate segment by any means as described above to form a smoking article.This method can include supplying a wrapping material that surrounds at least a portion of a heat generating segment, a substrate cavity, a tobacco rod, at least a portion of a second substrate cavity, and a second heat generating segment, and at least a portion of a second foil strip of the wrapping material that surrounds the second substrate cavity, the foil strip and the second foil strip being aligned at separate intervals from each other, the intervals being calibrated to accurately and repeatedly dispose the foil strip and the second foil strip in a desired position relative to the substrate cavity, the second substrate cavity, the heat generating segment, and the second heat generating segment.

[0115] Such two-up rods and / or intermediate segments can facilitate the handling of the substrate material during the manufacture of the smoking article. For example, the two-up rods and / or intermediate segments can be processed using the above-described standard processing equipment while holding the tobacco pellet substrate 863 between the heat generating segment 835 and the tobacco rod 869 and within the substrate cavity 856. In other words, the tobacco pellet substrate can be housed within the two-up rods and / or intermediate segments to avoid movement and / or loss of the tobacco pellet substrate while allowing further processing to be completed. Smoking articles of the type disclosed herein can be assembled as disclosed, for example, in U.S. Patent No. 5,469,871 to Barnes et al., or U.S. Patent Application Publication No. 2012 / 0042885 to Stone et al. or 2010 / 0186757 to Crooks et al., each of which is incorporated herein by reference.

[0116] In realizing the noted benefits and advantages associated with the present disclosure, in view of the possible interrelationships between aspects of the present disclosure, the present disclosure thus particularly and expressly includes, without limitation, embodiments representative of various combinations of the disclosed aspects. Accordingly, the present disclosure includes any combination of two, three, four or more such features or elements, whether or not the features or elements of the present disclosure are explicitly combined or otherwise cited in the description of specific embodiments herein. Unless the context of the present disclosure specifically dictates otherwise, the present disclosure is intended to be read integrally such that any separable features or elements of the present disclosure, i.e., those intended to be combinable, in any of such aspects and embodiments, should be considered so.

[0117] Experiment The present invention is illustrated more fully by the following examples, which are set forth to exemplify the present invention and should not be construed as limiting it. In each example, the ignitability of each fuel element is determined by placing the fuel element in a smoking article of the general specifications described in FIG. 1 and placing the smoking article in a holder. Thereafter, the fuel element is exposed to a flame for a set time (e.g., 0.5 seconds, 1.0 seconds, etc.) and then a puff of approximately 55 ml volume is taken on the smoking article. Next, the fuel element is removed from the flame and allowed to elapse for 15 seconds. Thereafter, a second puff of the same volume is taken. If the fuel element burns orange / red during the second puff, it is considered ignited. The same general experiment is repeated, with each experiment using a gradually longer set time of exposure to the flame until the fuel element is considered to have ignited at the time of the second puff. The lowest set time at which the fuel element continues to ignite at the time of the second puff is recorded as the ignitable time. Thus, for example, if a particular fuel element is exposed to a flame for 0.5 seconds according to the above test and does not burn orange or red during the second puff, but burns orange or red when retested at an exposure time of 1.0 seconds to the flame, this ignitable time is considered 1.0 second.

Example

[0118] [Example 1]: Use of ceramic materials or glass bubbles as ignition aids Several fuel element compositions are formed that include milled carbon, guar gum as a binder, calcium carbonate, and graphite, and non-combustion heated cigarettes are constructed therewith. The time required to ignite each fuel element composition is measured and compared to a commercially available ECLIPSE product (which has 5 outer grooves in the fuel element) and another control fuel element having 8 outer grooves in the fuel element. The compositions tested include various amounts of ceramic microspheres (W-610 microspheres available from 3M), including microsphere content levels of 0.05 wt%, 0.075 wt%, and 0.1 wt% (in this case, the amount of milled carbon is reduced to accommodate the ceramic microspheres). Some of the experimental compositions are fabricated into fuel elements having either 5 or 8 outer grooves, and in one example, having both 8 grooves and a central hole therethrough.

[0119] The ECLIPSE product with 5 grooves (no ceramic microspheres) has an ignitable time of 6.0 - 6.5 seconds. The 8-groove control (no ceramic microspheres) has an ignitable time of 5.0 - 5.5 seconds. The 8-groove control with a central hole (no ceramic microspheres) has an ignitable time of 3.5 seconds.

[0120] The ignitable time of the experimental fuel element with 0.05 wt% ceramic microspheres and 5 grooves is 3.5 - 4.0 seconds. The ignitable times of the experimental fuel elements with 8 grooves and 0.05 wt%, 0.075 wt%, or 0.1 wt% ceramic microspheres are 3.0 - 3.5 seconds, 3.5 seconds, and 2.8 - 3.0 seconds, respectively. The fuel element with 8 grooves, a central hole, and 0.1 wt% ceramic microspheres has an ignitable time of 1.5 seconds.

[0121] A similar test was conducted with a glass bubble (also available from 3M) at a content level of 0.05 wt%. The fuel element containing glass bubbles and having eight grooves and a central hole has an ignition time of 1.8 - 2.0 seconds.

[0122] A similar test was conducted using a fuel element composition containing alumina powder (available from CeramTec, product number T64 - 325) at a content level of 0.1 wt% and having eight outer grooves on the fuel element. The ignition time is in the range of 3.0 - 3.5 seconds.

[0123] A similar test was conducted using a fuel element composition containing sand (available from ACROS Organics, Fisher Scientific) at a content level of 0.1 wt% and having eight outer grooves on the fuel element. The ignition time is in the range of 3.2 - 3.4 seconds.

[0124] A similar test was conducted using a fuel element composition containing C - glass (glass fiber) particles (formed by cutting small pieces from the insulation mat of ECLIPSE products) at a content level of 0.1 wt% and having eight outer grooves on the fuel element. The ignition time is in the range of 3.2 - 4.0 seconds.

[0125] As can be seen, the presence of any of various ceramic materials significantly shortened the ignition time compared to the control fuel element.

[0126] [Example 2]: Use of impregnated carbon particles or cellulose particles as an ignition aid Similar to Example 1, several fuel element compositions are formed that include milled carbon, guar gum as a binder, calcium carbonate, and graphite, and a non-combustion heated cigarette is constructed therewith. The time required to ignite each fuel element composition is measured and compared to a commercially available ECLIPSE product. The compositions tested included the following: (A) milled carbon, guar gum, calcium carbonate, graphite; (B) milled carbon, guar gum, calcium carbonate, graphite, and 5 wt% impregnated carbon (ST1-X impregnated carbon available from Calgon Corporation), with the milled carbon content being 5% less than (A); (C) the composition of (B) except having 10 wt% impregnated carbon, with the milled carbon content being 10% less than (A); (D) the composition of (C) except having 15 wt% impregnated carbon, with the milled carbon content being 15% less than (A); (E) milled carbon, guar gum, calcium carbonate, graphite, and 5 wt% cellulose particles (Sigmacell cellulose available from Sigma-Aldrich), with all other components being reduced substantially proportionally compared to (A); (F) milled carbon, guar gum, calcium carbonate, graphite, 10 wt% ST1-X activated carbon, and 5 wt% Sigmacell cellulose, with all other components being reduced, but the milled carbon being reduced the most compared to (A); and (G) the composition of (B) except having 3 wt% impregnated carbon, with the graphite content being 3% less than (A).

[0127] The results of the ignition probability tests are shown in Table 1. As shown, the presence of impregnated carbon and / or cellulose particles shortens the time required to ignite the fuel element.

[0128] [Table 1]

[0129] [Example 3]: Use of Inorganic Salts as Ignition Aids Form several fuel element compositions comprising milled carbon, guar gum as a binder, calcium carbonate, and graphite, and construct a non-combustion heated cigarette therewith. Measure the time required to ignite each fuel element composition and compare it with a commercially available ECLIPSE product (which has 5 outer grooves in the fuel element) and another control fuel element having 8 outer grooves in the fuel element.

[0130] Contain either sodium chloride particles or potassium chloride at a content level of 0.1% by weight, and perform a test similar to Example 1 using a fuel element composition having 8 outer grooves on the fuel element. The ignitable time of the fuel element containing sodium chloride is 2.8 - 3.0 seconds, and the ignitable time of the fuel element containing potassium chloride is 2.9 seconds. Therefore, the ignitable time of the experimental composition containing an inorganic salt is considerably shorter than that of the control fuel element specified in Example 1.

[0131] Many modifications and other aspects of the present disclosure described herein will come to mind to those of ordinary skill in the art having the benefit of the teachings presented in the foregoing description and the related drawings. For example, those of ordinary skill in the art will understand that the embodiments described herein for various implementations can be practiced within the scope of the present disclosure, including that the features described herein for various embodiments can be combined with each other and / or with currently known or later developed technologies while remaining within the scope of the claims presented herein. Accordingly, it should be understood that the present disclosure is not limited to the specific embodiments disclosed and that equivalents, modifications, and other aspects are intended to be included within the scope of the appended claims. Specific terms are used herein, but these are used in a general and descriptive sense only and not for purposes of limitation.

Claims

**Claim 1** An aerosol-forming material, and One or more aerosol-generating elements processed to form beads or pellets and adapted to impart a smoky flavor or aroma as a result of smoking the beads or pellets with wood-generated smoke, and A heat source for providing heat to volatilize the aerosol-forming material within the aerosol-generating segment without thermal decomposition of the aerosol-generating segment, a smoking article comprising. **Claim 2** The smoking article according to claim 1, wherein the one or more aerosol-generating elements are derived from smoke from a combustible source. **Claim 3** The smoking article according to claim 1, wherein the wood is selected from the group consisting of hickory, maple, oak, apple, cherry, mesquite, and combinations thereof. **Claim 4** The smoking article according to claim 1, wherein the aerosol-generating segment comprises a base material as a carrier for the aerosol-forming material. **Claim 5** The smoking article according to claim 4, wherein the base material is treated with a tobacco additive. **Claim 6** The smoking article according to claim 1, wherein the one or more aerosol-generating elements comprise one or more of particulate tobacco, tobacco extract, and nicotine, and the nicotine is in free base form, salt form, or exists as a complex or solvate. **Claim 7** The smoking article according to claim 6, wherein the one or more aerosol-generating elements further comprise one or more fillers, binders, flavorings, and combinations thereof. **Claim 8** The smoking article according to claim 1, wherein the aerosol-forming material is dissolved or dispersed in a liquid carrier. **Claim 9** The smoking article according to claim 1, wherein the aerosol-forming material is selected from the group consisting of glycerin, propylene glycol, water, and combinations thereof.

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