SMOKING ARTICLE COMPRISING AN ISOLATED FUEL HEAT SOURCE

专利摘要:
smoking article comprising an insulated combustible heat source. a smoking article (8) comprises: a combustible heat source (2) with a front (2a) and a rear (2b) part; an aerosol-forming substrate (10) downstream from the back (2b) of the combustible heat source (2); and a casing (40) that circumscribes the front (2a) and the rear (2b) of the fuel heat source (2). the housing (40) is in contact with the rear (2b) of the combustible heat source (2). all or part of the front (2a) of the fuel heat source (2) is reduced in diameter compared to the rear (2b) of the fuel heat source (2) so that the casing (40) is radially spaced from the entirety. or from the front portion (2a) of the combustible heat source (2) by the air gap (42) of at least about 0.5 mm.
公开号:BR112016012894B1
申请号:R112016012894-0
申请日:2014-12-29
公开日:2021-08-10
发明作者:Frederic Lavanchy；Ana Carolina Borges De Couraça
申请人:Philip Morris Products S.A.；
IPC主号:

专利说明:

[001] The present invention relates to a smoking article comprising a combustible heat source with an opposite front and rear, and an aerosol forming substrate downstream of the rear of the combustible heat source.
[002] Various smoking articles in which tobacco is heated rather than combusted have been proposed in the art. One of the goals of such 'heated' smoking articles is to reduce the already known harmful smoke constituents of the types produced by the combustion and pyrolytic degradation of tobacco in conventional cigarettes. In a known type of heated smoking article, an aerosol is generated by transferring heat from a combustible heat source to an aerosol-forming substrate located downstream of the combustible heat source. During smoking, volatile compounds are released from the aerosol forming substrate via heat transfer from the combustible heat source and embedded together with the air drawn through the smoking article. As the released compounds cool, they condense to form an aerosol that is inhaled by the user.
[003] The inclusion of a heat-conducting element around and in direct contact with at least a rear portion of the fuel heat source and at least a front portion of the aerosol forming substrate of the heated smoking article in order to ensure transfer of sufficient conductive heat from the fuel heat source to the aerosol-forming substrate to obtain an acceptable aerosol is known. For example, WO-A2-2009/022232 discloses a smoking article comprising a combustible heat source, an aerosol forming substrate downstream of the combustible heat source, and a heat conducting element around and in direct contact with a rear portion of the combustible heat source and with an adjacent front portion of the aerosol forming substrate.
[004] The combustion temperature of a combustible heat source for use in a heated smoking article should not be so high as to result in combustion or thermal degradation of the aerosol forming material during use of the heated smoking article. However, the combustion temperature of the combustible heat source must be high enough to generate enough heat to release enough volatile compounds from the aerosol forming material to produce an acceptable aerosol, especially during the first few puffs.
[005] A variety of carbon-containing heat sources for use in smoking articles have been proposed in the art. The combustion temperature of carbon-containing heat sources for use in heated smoking articles is typically between about 600°C and 800°C.
[006] It is known to wrap an insulating member around the periphery of a carbon-containing heat source of a heated smoking article in order to reduce the surface temperature of the heated smoking article.
[007] For example, US-A-4,714,082 discloses a smoking article comprising a fuel element containing fuel carbon, an aerosol generating means, a heat conducting member and a peripheral insulating member of resilient non-combustion material. , like a fiberglass jacket. The insulating member circumscribes at least part of the fuel element and advantageously at least part of the aerosol generating means.
[008] EP-A2-0 174 645 discloses smoking articles comprising a carbonaceous fuel element, a physically separate aerosol generating means including a substrate with an aerosol forming material, a heat-conducting member that contacts a part. of the fuel element, with the substrate and with the mouth. At least a portion of the fuel element is preferably provided with a peripheral insulating member, such as an insulating fiber jacket, which reduces radial heat loss and assists in retaining and directing heat from the fuel element to the aerosol generating means .
[009] The inclusion of a separate insulating member as disclosed in US-A-4,714.082 and EP-A2-0 174 645 may result in a heated smoking article with a cross section that is not constant along the length of the article. to smoke. This can negatively affect the appearance of the heated smoking article and can make it more difficult to securely attach the carbon-containing heat source within the heated smoking article. The inclusion of a separate insulating member as disclosed in US-A-4,714,082 and EP-A2-0 174 645 can also add complexity to the heated smoking article assembly.
[0010] It would be desirable to provide a smoking article with a reduced surface temperature close to the heat source, acceptable appearance and which can be reliably mounted.
[0011] According to the invention, there is provided a combustible heat source with a front and a back; an aerosol forming substrate downstream of the rear of the fuel heat source; and an enclosure circumscribing the front and rear of the combustible heat source, wherein the enclosure is in contact with the rear of the combustible heat source and wherein all or part of the front of the combustible heat source has diameter reduced compared to the rear of the combustible heat source so that the casing is radially spaced from all or part of the front of the combustible heat source by an air gap of at least about 0.5 mm.
[0012] As used herein, the term "aerosol-forming substrate" is used to describe a substrate capable of releasing, upon heating, volatile compounds that can form an aerosol. Aerosols generated from aerosol forming substrates of smoking articles according to the invention may be visible or invisible and may include vapors (e.g. fine particles of substances which are in a gaseous state and which are normally liquid or solid at room temperature ), as well as gases and liquid droplets of condensed vapors.
[0013] The aerosol forming substrate can be in the form of a plug or segment that comprises a material capable of releasing, upon heating, volatile compounds, which can form an aerosol, circumscribed by an envelope. If an aerosol-forming substrate is in the form of such a plug or segment, the entire plug or segment, including any housing, will be considered to be the aerosol-forming substrate.
[0014] As used herein, the terms "distal", "upstream", "front", "proximal", "downstream" and "rear" are used to describe the relative positions of the components or parts of the components of the smoking article in relation to the sense in which the user brings the article to smoke during use. Smoking articles according to the invention comprise a proximal end through which, in use, an aerosol exits the smoking article for delivery to a user. The proximal end may also be referred to as the mouth end. In use, a user brings on the proximal end of the smoking article in order to inhale an aerosol generated by the smoking article.
[0015] The combustible heat source is located at or near the distal end. The end of the mouth is downstream of the distal end. The proximal end may also be referred to as the downstream end of the smoking article, and the distal end may also be referred to as the upstream end of the smoking article. Components or component parts of smoking articles according to the invention may be described as being upstream or downstream of each other based on their relative positions between the proximal end and the distal end of the smoking article.
[0016] The front of the combustible heat source is at the upstream end of the combustible heat source. The upstream end of the combustible heat source is the end of the combustible heat source furthest from the proximal end of the smoking article. The rear of the combustible heat source is at the downstream end of the combustible heat source. The downstream end of the combustible heat source is the end of the combustible heat source closest to the proximal end of the smoking article.
As used herein, the term "longitudinal" is used to describe the direction between the proximal end and the opposite distal end of the smoking article.
[0018] As used herein, the terms "radial" and "transverse" are used to describe the direction perpendicular to the direction between the proximal end and the opposite distal end of the smoking article.
[0019] As used herein, the term "length" is used to describe the maximum longitudinal dimension of the smoking article. That is, the maximum dimension in the direction between the proximal end and the opposite distal end of the smoking article.
Smoking articles according to the invention include an air gap of at least 0.5 mm between at least a portion of the front of the combustible heat source and the housing. The inclusion of an air gap of at least about 0.5 mm between all or part of the front of the fuel heat source and the casing advantageously isolates the fuel heat source and thus reduces the surface temperature of the smoking article near the combustible heat source.
[0021] All or part of the front part of the combustible heat source of the smoking articles according to the invention has a reduced diameter compared to the rear part of the combustible heat source. The reduced diameter of all or part of the front of the combustible heat source compared to the rear of the combustible heat source allows the housing to be in contact with the rear of the combustible heat source despite the inclusion of a gap between all or part of the front of the combustible heat source and the enclosure. Advantageously, this helps to maintain the combustible heat source within the smoking article. This also helps to facilitate proper heat transfer from the fuel heat source to the aerosol forming substrate to provide an acceptable aerosol.
[0022] As used in this document, the term "in contact" is used to mean that there is no air gap between the enclosure and the rear of the combustible heat source.
[0023] The casing may be radially spaced from all or part of the front of the combustible heat source by an air gap of at least about 1.0 mm.
[0024] Preferably, the casing is radially spaced from all or part of the front of the combustible heat source by an air gap between about 0.5 mm and about 1.5 mm. The housing may be radially spaced from all or part of the front of the combustible heat source by an air gap between about 1.0 mm and about 1.5 mm.
[0025] Preferably, the casing is radially spaced at least about 50% from the front of the combustible heat source by an air gap. The housing may be radially spaced at least about 60% from the front of the combustible heat source by an air gap.
[0026] Preferably, the rear of the combustible heat source is a substantially constant cross section. Most preferably, the rear portion of the combustible heat source is a substantially circular and constant cross section.
[0027] Preferably, the front of the combustible heat source is a substantially constant cross section.
[0028] In certain embodiments, the entire front of the combustible heat source is reduced in diameter compared to the rear of the combustible heat source so that the casing is radially spaced from the entire front of the combustible heat source by the gap of air. In certain preferred embodiments, the front and rear of the combustible heat source are a substantially constant circular cross-section and the combustible heat source is a substantially T-shaped longitudinal section.
[0029] In other embodiments, only a portion of the front of the fuel heat source is reduced in diameter compared to the rear of the fuel heat source so that the casing is radially spaced only from a portion of the front of the fuel source. combustible heat by the air gap. In certain embodiments, the front portion of the fuel heat source comprises a plurality of circumferentially spaced longitudinal grooves of reduced diameter compared to the rear portion of the fuel heat source. In certain preferred embodiments, the front of the combustible heat source is a substantially constant star-shaped or sprocket-shaped cross section and the rear of the combustible heat source is a substantially constant circular cross-section.
[0030] Preferably, the combustible heat source has a length of about 7 mm and about 17 mm, more preferably between about 7 mm and about 15 mm, more preferably between about 7 mm and about 13 mm .
[0031] Preferably, the length of the front of the combustible heat source is at least 5 mm.
[0032] Preferably, the length of the front of the combustible heat source is between about 5 mm and about 12 mm.
[0033] Preferably, the length of the back of the combustible heat source is at least 3 mm.
[0034] Preferably, the length of the rear of the combustible heat source is between about 3 mm and about 6 mm.
Preferably, the rear portion of the combustible heat source has a diameter between about 5 mm and about 9 mm, more preferably between about 7 mm and about 8 mm.
[0036] Preferably, the rear of the combustible heat source has substantially the same diameter as the aerosol forming substrate.
[0037] The casing may be an outer casing. As used herein, the term "outer wrapper" is used to describe a wrapper that is visible on the outside of the smoking article.
[0038] Alternatively, the casing may be an inner casing. As used herein, the term "inner wrapper" is used to describe a wrapper that is not visible or is only partially visible on the outside of the smoking article. In such embodiments, the smoking article further comprises one or more additional layers of material overlying all or part of the wrapper. For example, the smoking article may comprise an additional wrapper that circumscribes all or part of the wrapper.
[0039] To facilitate the supply of oxygen to the front of the fuel heat source, one or more air inlets are preferably provided in the enclosure and, when present, in any additional layers of material overlying the enclosure, around the front of the combustible heat source.
[0040] Preferably, the physical integrity of the casing is maintained at the temperatures reached by the combustible heat source during ignition and combustion.
[0041] The casing may comprise heat-conducting material. The casing may comprise any suitable heat-conductive material or combination of materials with suitable thermal conductivity.
[0042] In these embodiments, the casing preferably comprises one or more heat-conducting materials with volumetric thermal conductivity between about 10 W per meter Kelvin (W/(m^K)) and about 500 W per meter Kelvin (W /(m^K)), more preferably between about 15 W per meter Kelvin (W/(m^K)) and about 400 W per meter Kelvin (W/(m^K)), at 23°C and a relative humidity of 50% as measured using the Modified Transient Plane Source (MTPS) method. Suitable heat conductive materials include, but are not limited to: metallic foils such as aluminum foil, steel foil, iron foil and copper foil; and metal alloy sheets.
[0043] Alternatively or additionally, the casing may comprise heat-insulating material. The housing may comprise any suitable heat insulating material or combination of materials. Suitable heat insulating materials include, but are not limited to: paper.
[0044] The casing can be formed from a single layer of heat-conductive material or from a single layer of heat-insulating material.
[0045] Alternatively, the casing may be formed of a multilayer or laminated material comprising one or more layers of heat-conductive material and one or more layers of heat-insulating material. In such embodiments, one or more layers of heat-conductive material can comprise any of the heat-conductive materials listed above.
[0046] In certain preferred embodiments, the casing may be formed of a laminated material comprising a radially inner layer of heat-insulating material facing the rear of the combustible heat material and a radially outer layer of the heat-conductive material.
[0047] In these embodiments, the inclusion of an enclosure comprising a combination of a radially inner layer of heat-insulating material and a radially outer layer of heat-conductive material advantageously conducts heat from the combustible heat source to the forming substrate of aerosol, limits the heat loss by radiation from the combustible heat source and isolates the combustible heat source.
[0048] In certain embodiments, the casing may be in direct contact with the rear of the combustible heat source. As used in this document, the term "direct contact" is used to mean direct contact between two components without any intermediate material, so that the surfaces of the components touch each other.
[0049] In other embodiments, the casing may be in indirect contact with the rear of the combustible heat source. In these embodiments, one or more layers of material are provided between the casing and the rear of the combustible heat source.
[0050] Smoking articles according to the invention may comprise a first heat-conducting element between the rear of the combustible heat source and the casing. In these embodiments, the first heat-conducting element underlies a part of the casing.
[0051] The first heat-conducting element may be around all or part of the rear of the combustible heat source. Preferably, the first heat-conducting element is around all or a portion of the back of the blind fuel heat source and at least a front portion of the aerosol-forming substrate. The first heat-conducting element is preferably resistant to combustion. In certain embodiments, the first heat-conducting element is oxygen-restricting. In other words, the first heat-conducting element inhibits or resists the passage of oxygen through the first heat-conducting element to the combustible heat source.
[0052] In certain embodiments, the first heat-conducting element may provide a substantially hermetic connection between the fuel heat source and the aerosol-forming substrate. This can advantageously prevent or inhibit flue gases from the combustible heat source from being readily drawn into the aerosol forming substrate through its periphery. Such a connection may also advantageously minimize or substantially prevent the transfer of convective heat from the fuel heat source to the aerosol-forming substrate by air drawn along the peripheries of the fuel heat source and the aerosol-forming substrate.
[0053] In certain embodiments, the first heat-conducting element may be around and in direct contact with all or a portion of the rear portion of the fuel heat source and at least a front portion of the aerosol-forming substrate. In these embodiments, all or a portion of the rear portion of the combustible heat source is circumscribed and is in direct contact with the first heat-conducting element and at least a front portion of the aerosol forming substrate is circumscribed and is in direct contact with the first heat-conducting element. In such embodiments, the first heat-conducting element provides a thermal connection between the combustible heat source and the aerosol forming substrate of smoking articles in accordance with the invention.
[0054] In certain embodiments, the entire length of the aerosol-forming substrate may be circumscribed by the first heat-conducting element.
[0055] In other embodiments, the first heat-conducting element may circumscribe only a front portion of the aerosol-forming substrate. In these embodiments, the aerosol-forming substrate extends downstream beyond the first heat-conducting element.
[0056] In embodiments where the first heat-conducting element circumscribes only a front portion of the aerosol-forming substrate, the aerosol-forming substrate preferably extends at least about 3 mm downstream beyond the first heat-conducting element . More preferably, the aerosol-forming substrate extends between about 3 mm and about 10 mm downstream beyond the first heat-conducting element. However, the aerosol forming substrate may extend less than 3 mm downstream beyond the first heat-conducting element.
[0057] Preferably, the front portion of the aerosol forming substrate circumscribed by the first heat conducting element is about 1 mm and about 10 mm in length, more preferably about 2 mm and about 8 mm in length, most preferably about 2 mm and about 6 mm long.
[0058] The first heat-conducting element comprises heat-conducting material. The first heat-conducting element may comprise any heat-conducting material or combination of materials with appropriate thermal conductivity.
[0059] Preferably, the first heat-conducting element comprises one or more heat-conducting materials with volumetric thermal conductivity between about 10 W per meter Kelvin (W/(m^K)) and about 500 W per meter Kelvin (W/(m^K)), more preferably between about 15 W per meter Kelvin (W/(m^K)) and about 400 W per meter Kelvin (W/(m^K)), at 23° C and a relative humidity of 50% as measured using the Modified Transient Plane Source (MTPS) method. Suitable heat conductive materials include, but are not limited to, foil wrappers such as, for example, aluminum foil wrappers, steel wrappers, iron foil wrappers and copper foil wrappers; and metal alloy sheet casings.
[0060] The first heat-conducting element may be composed of a single layer of heat-conductive material. Alternatively to this, the first heat-conductive element may be composed of a multi-layer or laminated material which comprises at least one layer of heat-conductive material in combination with one or more heat-conductive layers or non-heat-conductive layers. In such embodiments, the at least one layer of heat-conductive material can comprise any of the heat-conductive materials listed above.
[0061] In certain embodiments, the first heat-conducting element may be composed of a laminated material comprising at least one layer of heat-conductive material and at least one layer of heat-insulating material. In such embodiments, the radially inner layer of the first heat-conducting element, facing the rear of the fuel heat source, may be a layer of heat-conductive material and the radially outer layer of the first heat-conducting element may be a layer of thermal insulating material.
Preferably, the thickness of the first heat conducting element is between about 5 microns and about 50 microns, more preferably between about 10 microns and about 30 microns and most preferably about 20 microns. In certain preferred embodiments, the first heat-conducting element comprises aluminum foil having a thickness of about 20 microns.
[0063] As an alternative or in addition to a first heat-conducting element underlying the shell part, smoking articles according to the invention may comprise a second heat-conducting element overlying all or part of the shell.
[0064] If smoking articles according to the invention comprise a first heat-conducting element and a second heat-conducting element, the second heat-conducting element is preferably around at least a part of the first element. heat conductor. That is, the second heat-conducting element preferably overlaps at least a part of the first heat-conducting element. In these embodiments, at least a portion of the second heat-conducting element is radially separated from the first heat-conducting element by the housing.
[0065] As used in this document, the term "radially separated" is used to indicate that at least part of the second heat-conducting element is spaced from the first heat-conducting element in a radial direction across the casing so that there is no contact. between at least a portion of the second heat-conducting element and the first heat-conducting element.
[0066] Preferably, all or substantially all of the second heat-conducting element is radially separated from the first heat-conducting element by the enclosure, so that there is substantially no direct contact between the first heat-conducting element and the second conductive element of heat. This advantageously limits or inhibits conductive heat transfer from the first heat-conducting element to the second heat-conducting element. Advantageously, this results in the second heat-conducting element maintaining a lower temperature than the first heat-conducting element.
[0067] In these embodiments, the second heat-conducting element advantageously reduces the heat losses of the first heat-conducting element. In use, the second heat-conducting element will increase in temperature during smoking of the smoking article as heat is generated by the combustible heat source. Increasing the temperature of the second heat-conducting element reduces the temperature differential between the first heat-conducting element, the casing and any additional intervening layers of material, so that heat losses from the first heat-conducting element can be reduced. By reducing heat losses from the first heat-conducting element, the second heat-conducting element advantageously helps to better maintain the temperature of the first heat-conducting element within a desired temperature range.
[0068] The second heat-conducting element comprises heat-conducting material. The second heat-conducting element may comprise any heat-conducting material or combination of materials with appropriate thermal conductivity.
Preferably, the second heat-conducting element comprises one or more heat-conducting materials with volumetric thermal conductivity between about 10 W per meter Kelvin (W/(m^K)) and about 500 W per meter Kelvin (W/(m^K)), more preferably between about 15 W per meter Kelvin (W/(m^K)) and about 400 W per meter Kelvin (W/(m^K)), at 23 °C and a relative humidity of 50% as measured using the Modified Transient Plane Source (MTPS) method. Suitable heat conductive materials include, but are not limited to, foil wrappers such as, for example, aluminum foil wrappers, steel wrappers, iron foil wrappers and copper foil wrappers; and metal alloy sheet casings.
[0070] If smoking articles according to the invention comprise a first heat-conducting element and a second heat-conducting element, the first heat-conducting element and the second heat-conducting element may comprise heat-conducting material or materials. same or different heat.
[0071] In certain preferred embodiments, the first heat-conducting element and the second heat-conducting element comprise the same heat-conducting material. In certain preferred embodiments, the first heat-conducting element and the second heat-conducting element comprise aluminum foil.
[0072] If smoking articles according to the invention comprise a first heat-conducting element and a second heat-conducting element, preferably, the second heat-conducting element comprises one or more heat-reflective materials, such as aluminum or steel. In such embodiments, in use situation, the second heat-conducting element advantageously reflects heat radiating from the first heat-conducting element back to the first heat-conducting element. This further reduces heat losses from the first heat-conducting element so that the temperature of the first heat-conducting element can be better controlled and the combustible heat source can be kept at a higher temperature.
[0073] As used in this document, the term "heat reflective material" refers to a material that has relatively high heat reflectivity and relatively low heat emissivity, so that the material reflects a greater proportion of incident radiation from the surface than the emitted proportion. Preferably, the material reflects more than 50% incident radiation, more preferably more than 70% incident radiation and most preferably more than 75% incident radiation.
[0074] If smoking articles according to the invention comprise a first heat-conducting element and a second heat-conducting element comprising a heat-reflective material, preferably all or substantially all of the second heat-conducting element is radially separated from the first heat-conducting element by the casing to facilitate the reflection of heat from the second heat-conducting element to the first heat-conducting element.
[0075] The reflectivity of the second heat-conducting element can be improved by providing the second heat-conducting element with a glossy radially inner surface, wherein the radially inner surface is the surface of the second heat-conducting element whose face is radially toward the outer surface of the first heat-conducting element.
[0076] The second heat-conducting element may be composed of a single layer of heat-conductive material. Alternatively to this, the second heat-conductive element can be composed of a multi-layer or laminated material which comprises at least one layer of heat-conductive material in combination with one or more heat-conductive layers or non-heat-conductive layers. In such embodiments, the at least one layer of heat-conductive material can comprise any of the heat-conductive materials listed above.
[0077] In certain embodiments, the second heat-conducting element may be composed of a laminated material comprising at least one layer of heat-conductive material and at least one layer of heat-insulating material. In such embodiments, the radially inner layer of the second heat-conducting element, facing the casing, may be a layer of heat-conductive material and the radially outer layer of the second heat-conductive element may be a layer of heat-conductive material. .
[0078] If smoking articles according to the invention comprise a first heat-conducting element and a second heat-conducting element, the thickness of the second heat-conducting element may be substantially equal to the thickness of the first conductive element. of heat. Alternatively, the first heat-conducting element and the second heat-conducting element can have different thicknesses from each other.
[0079] Preferably, the thickness of the second heat conducting element is between about 5 microns and about 100 microns, more preferably between about 5 microns and about 80 microns.
[0080] Preferably, the second heat-conductive element comprises one or more layers of heat-conductive material having a thickness between about 2 microns and about 50 microns, more preferably between about 4 microns and about 30 microns.
[0081] In certain preferred embodiments, the second heat-conducting element may comprise aluminum foil with a thickness of about 20 microns.
[0082] In certain embodiments, the second heat-conducting element may comprise a laminated material comprising an outer layer of aluminum with a thickness of about 5 microns and about 6 microns and an inner layer of paper.
[0083] If smoking articles according to the invention comprise a first heat-conducting element and a second heat-conducting element, the position and extent of the second heat-conducting element with respect to the first heat-conducting element, the combustible heat source and the aerosol-forming substrate can be adjusted to control the heating of the aerosol-forming substrate during smoking.
[0084] The second heat-conducting element may be positioned around one or both of the front and rear parts of the combustible heat source.
[0085] Where the casing comprises a single layer of heat-insulating material, the second heat-conducting element is preferably positioned around the front and rear of the combustible heat source.
[0086] Alternatively or additionally, the second heat-conducting element may be positioned around at least a part of the aerosol-forming substrate.
[0087] In certain embodiments, the aerosol forming substrate may abut the rear of the combustible heat source.
[0088] As used in this document, the term "pull" is used to describe the aerosol forming substrate being in direct contact with the rear of the combustible heat source or with a barrier coating impermeable to substantially non-combustible air provided over the rear of the combustible heat source.
[0089] In other embodiments, the aerosol forming substrate may be spaced from the rear of the combustible heat source. That is, there may be a space or gap between the aerosol forming substrate and the rear face of the combustible heat source.
[0090] Smoking articles according to the invention may further comprise one or more of the first air inlets around the periphery of the aerosol-forming substrate.
[0091] In use, fresh air is drawn into the aerosol-forming substrate through the first air inlets. Air drawn into the aerosol forming substrate through the first air inlets passes downstream, through the smoking article, from the aerosol forming substrate and leaves the smoking article through the proximal end thereof.
[0092] During a user's puff, fresh air drawn into the aerosol-forming substrate by one or more of the first inlets can advantageously reduce the temperature of the aerosol-forming substrate of smoking articles according to the invention. This can advantageously substantially prevent or inhibit spikes in the temperature of the aerosol-forming substrate of smoking articles according to the invention during puffing by a user.
[0093] In certain preferred embodiments, the one or more first air inlets are located near the downstream end of the aerosol forming substrate.
[0094] Alternatively or additionally, if the aerosol forming substrate is spaced from the rear of the combustible heat source, the smoking articles according to the invention may further comprise one or more second air inlets between the rear of the combustible heat source and the aerosol forming substrate. When in use, fresh air is drawn into the space between the combustible heat source and the aerosol forming substrate through the second air inlets. Air drawn into the space between the fuel heat source and the aerosol forming substrate through the second air inlets passes downstream through the smoking article from the space between the fuel heat source and the aerosol forming substrate and exits the smoking article through the proximal end thereof.
[0095] During blowing by a user, fresh air drawn in through one or more of the second air inlets between the rear of the combustible heat source and the aerosol forming substrate can also advantageously reduce the temperature of the aerosol forming substrate of smoking articles according to the invention. This can advantageously substantially prevent or inhibit spikes in the temperature of the aerosol-forming substrate of smoking articles according to the invention during puffing by a user.
[0096] Alternatively or additionally, the smoking articles according to the invention may further comprise one or more third air inlets of the aerosol-forming substrate.
[0097] It should be appreciated that smoking articles according to the invention may comprise any combination of one or more first air inlets around the periphery of the aerosol former, one or more second air inlets between the rear of the combustible heat source and the aerosol-forming substrate and one or more third air inlets downstream of the aerosol-forming substrate.
Smoking articles according to the invention may comprise a first substantially non-combustible air-impermeable barrier between the rear of the combustible heat source and the aerosol forming substrate.
[0099] As used herein, the term "non-combustible" is used to describe a substantially non-combustible barrier at temperatures reached by the combustible heat source during combustion and ignition thereof.
[00100] The first barrier may abut either or both the rear of the fuel heat source and/or the front of the aerosol forming substrate. Alternatively, the first barrier may be spaced from one or both of the rear portions of the combustible heat source and the aerosol former substrate.
[00101] The first barrier may be adhered or affixed to one or both of the rear parts of the fuel heat source and the aerosol forming substrate.
[00102] In certain preferred embodiments, the first barrier comprises a substantially non-combustible first air-impermeable barrier coating provided on a rear face of the rear portion of the combustible heat source. In such embodiments, preferably, the first barrier comprises a first barrier coating provided over at least substantially the entire rear face of the rear portion of the fuel heat source. More preferably, the first barrier comprises a first barrier coating provided over the entire rear face of the rear portion of the fuel heat source.
[00103] As used herein, the term "coating" is used to describe a layer of material that covers and is adhered to the heat source.
[00104] The first barrier can advantageously limit the temperature to which the aerosol-forming substrate is exposed during ignition and combustion of the combustible heat source, thus helping to prevent or reduce thermal degradation or combustion of the aerosol forming substrate during use of the smoking article. This is particularly advantageous where the combustible heat source comprises one or more additives to assist in igniting the combustible heat source.
[00105] The inclusion of a first substantially non-combustible air-impermeable barrier between the rear of the combustible heat source and the aerosol forming substrate may also advantageously prevent or substantially inhibit the migration of components from the forming substrate of aerosol from the smoking articles according to the invention to the combustible heat source during storage of the smoking articles.
[00106] Alternatively or additionally, the inclusion of a first substantially non-combustible air-impermeable barrier between the rear of the combustible heat source and the aerosol-forming substrate may advantageously prevent or substantially inhibit the migration of substrate components smoking article aerosol former according to the invention for the source of combustible heat during use of the smoking article.
[00107] The inclusion of a first substantially non-combustible air-impermeable barrier between the rear of the combustible heat source and the aerosol forming substrate may be particularly advantageous if the aerosol forming substrate comprises at least one aerosol former. In such embodiments, the inclusion of a first substantially non-combustible air-impermeable barrier between the rear of the combustible heat source and the aerosol forming substrate may advantageously prevent or substantially inhibit the migration of at least one aerosol former from the aerosol forming substrate to the combustible heat source during storage and use of the smoking article. The decomposition of at least one aerosol former during use of the smoking articles can, therefore, advantageously be substantially avoided or reduced.
[00108] Depending on the characteristics and performance desired for the smoking article, the first barrier may have a low thermal conductivity or a high thermal conductivity. In certain embodiments, the first barrier can be formed of material that has a thermal conductivity by mass of between about 0.1 W per meter Kelvin (mW/(m*K)) and about 200 W per meter Kelvin (W/ (m^K)), at 23°C and 50% relative humidity, as measured using the modified transient flat source (MTPS) method.
[00109] The thickness of the first barrier can be adjusted accordingly to achieve good smoking performance. In certain embodiments, the first barrier can be between about 10 microns and about 500 microns thick.
[00110] The first barrier may be formed from one or more suitable materials that are substantially thermally stable and non-combustible at the temperatures reached by the combustible heat source during ignition and combustion. Suitable materials are known in the art and include, but are not limited to, clays (such as, for example, bentonite and kaolinite), glasses, minerals, ceramic materials, resins, metals and combinations thereof.
[00111] Preferred materials from which the first barrier can be formed include clays and glasses. The most preferred materials from which the barrier can be formed include copper, aluminum, stainless steel, alloys, alumina (Al2O3), resins and mineral glues.
[00112] In certain preferred embodiments, the first barrier comprises a clay coating comprising a 50/50 mixture of bentonite and kaolinite provided on the rear face of the rear portion of the combustible heat source. In other preferred embodiments, the first barrier comprises a glass coating, more preferably a sintered glass coating, provided on the rear face of the rear portion of the combustible heat source.
[00113] In certain particularly preferred embodiments, the first barrier comprises an aluminum coating provided on the rear face of the rear portion of the combustible heat source.
[00114] Preferably, the barrier has a thickness of at least about 10 microns.
[00115] Due to the slight permeability of clays to air, in embodiments where the first barrier comprises a clay coating provided on the rear face of the rear of the fuel heat source, the clay coating is more preferably of a thickness at least about 50 microns, and more preferably between about 50 microns and about 350 microns.
[00116] In embodiments where the first barrier is formed from one or more air-impermeable materials, such as aluminum, the first barrier may be thinner and will generally preferably have a thickness of less than about 100 microns and more preferably about 20 microns.
[00117] In embodiments where the first barrier comprises a glass coating provided on the rear face of the rear of the fuel heat source, the glass coating is preferably less than about 200 microns thick.
[00118] The thickness of the first barrier can be measured using a microscope, a scanning electron microscope (SEM) or any other suitable measurement methods known in the art.
[00119] If the barrier comprises a first barrier coating provided on the rear face of the rear part of the fuel heat source, the first barrier coating may be applied so as to cover and adhere to the rear face of the rear part of the heat source fuel by any suitable methods known in the art, including, but not limited to, spray coating, vapor deposition, dipping, metal transfer (e.g., brushing or gluing), electrostatic deposition, or any combination thereof.
[00120] For example, the first barrier coating can be made by preforming a barrier in the approximate size and shape of the rear face of the rear of the fuel heat source and applying it to the rear face of the rear of the source of combustible heat to mask and adhere to at least substantially the entire rear face of the rear of the combustible heat source. Alternatively, the first barrier coating can be cut or tampered with after it has been applied to the rear face of the rear of the combustible heat source. In a preferred embodiment, the aluminum foil is applied to the rear face of the rear of the fuel heat source by gluing or pressing it to the fuel heat source, and is then cut or tampered with so that the aluminum foil covers and adheres to at least substantially the entire rear face of the rear of the combustible heat source, preferably the rear face of the combustible heat source in its entirety.
[00121] In another preferred embodiment, the first barrier coating is formed by applying a solution or suspension of one or more suitable coating materials to the rear face of the rear of the combustible heat source. For example, the first barrier coating can be applied to the rear face of the rear of the fuel heat source by immersing the rear face of the rear of the fuel heat source in a solution or suspension of one or more suitable coating materials or by brushing or spray coating of a solution or suspension or by electrostatic deposition of a powder or powder mixture of one or more suitable coating materials on the external face of the external portion of the combustible heat source. If the first barrier coating is applied to the rear face of the rear of the fuel heat source by electrostatic deposition of a powder or powder mixture of one or more suitable coating materials on the rear face of the rear of the fuel heat source, the Rear face of the rear of the fuel heat source is preferably pretreated with water glass prior to electrostatic deposition. Preferably, the first barrier coating is applied by spray coating.
[00122] The first barrier coating can be formed by a single application of a solution or suspension of one or more suitable coating materials to the rear face of the rear of the fuel heat source. Alternatively, the first barrier coating can be formed by multiple applications of a solution or suspension of one or more suitable coating materials to the rear face of the rear portion of the fuel heat source. For example, the first barrier coating can be formed by one, two, three, four, five, six, seven or eight successive applications of a solution or suspension of one or more suitable coating materials to the rear face of the source rear part. of combustible heat.
[00123] Preferably, the first barrier coating is formed by between one and ten applications of a solution or suspension of one or more suitable coating materials to the rear face of the rear of the combustible heat source.
[00124] After application of the solution or suspension of one or more coating materials to the rear face of the rear part thereof, the combustible heat source can dry to form the first barrier coating.
[00125] If the first barrier coating is formed by multiple applications of a solution or suspension of one or more suitable coating materials to the rear face of the back of the same, the combustible heat source may need to dry out between successive applications of the solution or suspension.
[00126] Alternatively or in addition to drying, after applying a solution or suspension of one or more coating materials to the rear face of the rear of the fuel heat source, the coating material in the fuel heat source may be sintered so as to form the first barrier coating. Sintering the first barrier coating is particularly preferred where the first barrier coating is a glass or ceramic coating. Preferably, the first barrier coating is sintered at a temperature between about 500°C and about 900°C, and more preferably at about 700°C.
[00127] Smoking articles according to the invention may comprise an unblinded combustible heat source. As used in this document, the term "non-blind" is used to describe a combustible heat source including at least one air flow channel that extends from the front face of the front part of the fuel heat source to the rear face of the part. rear of the combustible heat source.
[00128] As used in this document, the term "airflow channel" is used to describe a channel that extends along the length of a combustible heat source through which air can be drawn downstream for inhalation by a user.
[00129] In smoking articles according to the invention, comprising non-blinding combustible heat source, heating of the aerosol-forming substrate occurs by conduction and by forced convection.
[00130] The one or more airflow channels may comprise one or more attached airflow channels.
[00131] As used herein, the term "attached" is used to describe air flow channels that extend through the interior of the non-blind combustible heat source and are surrounded by the non-blind combustible heat source.
[00132] Alternatively to, or in addition to, the one or more air flow channels may comprise one or more unclosed air flow channels. For example, one or more air flow channels may comprise one or more grooves or other non-closed air flow channels that extend along the exterior of the rear portion of the non-blinded combustible heat source.
[00133] The one or more airflow channels may include one or more closed airflow channels or one or more non-closed airflow channels or a combination thereof.
[00134] In some embodiments, smoking articles in accordance with the invention may comprise one, two or three air flow channels extending from the front face of the front of the non-blind combustible heat source to the face rear of the rear of the non-blind combustible heat source.
[00135] In certain preferred embodiments, smoking articles according to the invention comprise a single air flow channel extending from the front face of the front of the non-blind fuel heat source to the rear face of the part. rear of the non-blind combustible heat source.
[00136] In certain especially preferred embodiments, smoking articles in accordance with the invention comprise a single substantially central or axial air flow channel extending from the front face of the front of the non-combustible heat source. blind to the rear face of the rear of the non-blind combustible heat source.
[00137] In such embodiments, the diameter of the single airflow channel is preferably between about 1.5 mm and about 3 mm.
[00138] It should be noted that, in addition to the one or more air flow channels through which air can be drawn in for inhalation by a user, smoking articles according to the invention may comprise non-heat sources. blinds comprising one or more closed or blocked passages through which air cannot be drawn in for inhalation by the user.
[00139] For example, smoking articles according to the invention may comprise non-blind combustible heat sources comprising one or more air flow channels extending from the front face of the front of the combustible heat source non-blind to the rear face of the rear of the non-blind fuel heat source and one or more closed passages extending from the front face of the front of the non-blind fuel heat source to only half the length of the heat source fuel.
[00140] The inclusion of one or more closed air passages increases the surface area of the unblinded combustible heat source that is exposed to oxygen in the air and can advantageously facilitate continuous combustion ignition of the unblinded combustible heat source.
[00141] If the smoking articles according to the invention comprise a non-blind combustible heat source and a first substantially non-combustible air-impermeable barrier between the rear of the combustible heat source and the aerosol forming substrate , the first barrier must be configured to allow air entering the smoking article through one or more air flow channels to be drawn downstream through the smoking article.
[00142] As an alternative or in addition to a first substantially non-combustible air-impermeable air barrier between the rear of the combustible heat source and the aerosol-forming substrate, smoking articles according to the invention comprising a source of non-blind combustible heat may comprise a second substantially non-combustible air-impermeable barrier between the non-blind combustible heat source and one or more air flow channels.
[00143] The second barrier between the non-blinding combustible heat source and one or more air flow channels can advantageously and substantially prevent or inhibit combustion and decomposition products formed during ignition and combustion of the combustible heat source non-blinded air drawn into the interior of smoking articles in accordance with the invention through one or more air flow channels as the inhaled air passes through one or more air flow channels. This is particularly advantageous when the non-blinded combustible heat source comprises one or more additives to aid in the ignition or combustion of the non-blinded combustible heat source.
[00144] The inclusion of a second substantially airtight non-combustible barrier between the non-blind heat source and the one or more air flow channels may also advantageously and substantially prevent or inhibit the activation of combustion of the combustible heat source not blind during user drags. This can prevent or inhibit spikes in the temperature of the aerosol forming substrate during puffs by a user.
[00145] By preventing or inhibiting the combustion activation of the non-blinding combustible heat source, thereby preventing or inhibiting excessive temperature increases in the aerosol-forming substrate, it can be avoided, in a way advantageously, combustion or pyrolysis of the aerosol-forming substrate under intense blowing regimes. Furthermore, the impact of a user's puff regimen on the main aerosol can be advantageously minimized or reduced.
[00146] The second barrier between the non-blind combustible heat source and one or more air flow channels may be adhered or affixed to the non-blind combustible heat source.
[00147] In given embodiments, the second barrier comprises a second substantially air-impermeable non-combustible barrier coating provided on an inner surface of the one or more air flow channels. In such embodiments, the second barrier preferably comprises a second barrier coating provided over at least substantially the entire internal surface of the one or more airflow channels. More preferably, the second barrier comprises a second barrier coating provided over at least substantially the entire interior surface of the one or more air flow channels.
[00148] In other embodiments, the second barrier coating may be provided by inserting a liner within one or more airflow channels. For example, where the one or more air flow channels comprise one or more closed air flow channels extending into the unblinded combustible heat source, a hollow non-combustible substantially airtight tube may be inserted into each. one of the airflow channels.
[00149] Depending on the performance and desired characteristics of the smoking article, the second barrier may have low thermal conductivity or high thermal conductivity. Preferably, the second barrier has a low thermal conductivity.
[00150] The thickness of the second barrier can be adjusted appropriately so that it can have a good smoking performance. In certain embodiments, the second barrier can be between about 30 microns and about 200 microns thick. In a preferred embodiment, the second barrier is between about 30 microns and about 100 microns thick.
[00151] The second barrier may be formed from one or more suitable materials that are substantially thermally stable and non-combustible at the temperatures reached by the non-blind combustible heat source during ignition and combustion. Suitable materials are known in the art and include, but are not limited to, for example: clays; metal oxides such as iron oxide, alumina, titania, silica, silica-alumina, zirconia and wax; zeolites; zirconium phosphate; and other ceramic materials or combinations thereof.
[00152] Preferred materials from which the second barrier can be formed include clays, glasses, aluminum, iron oxide and combinations thereof. If desired, catalytic ingredients, such as ingredients that promote the oxidation of carbon monoxide to carbon dioxide, can be incorporated into the second barrier. Suitable catalytic ingredients include, among others, for example, platinum, palladium, transition metals and their oxides.
[00153] Where the second barrier comprises a second barrier coating provided on an inner surface of one or more air flow channels, the second barrier coating may be applied to the inner surface of the one or more air flow channels of a or more airflow channels by any suitable method, such as the methods described in US-A-5,040,551. For example, the inner surface of the one or more airflow channels can be sprayed, moistened or painted with a solution or suspension of the barrier coating. In certain preferred embodiments, the second barrier coating is applied to the inner surface of one or more airflow channels by the process described in WO-A2-2009/074870 as the combustible heat source is extruded.
[00154] Alternatively, smoking articles according to the invention may comprise a blind combustible heat source. As used in this document, the term "blind" is used to describe a combustible heat source that does not include any airflow channel that extends from the front face to the rear face of the combustible heat source.
[00155] In use, air drawn through smoking articles according to the invention comprising a blind combustible heat source for inhalation by a user does not pass through any air flow channel along the source of combustible heat blinds. The lack of any airflow channel through the blind combustible heat source substantially and advantageously prevents or inhibits activation of combustion from the blind combustible heat source during puffs by a user. This substantially prevents or inhibits spikes in the temperature of the aerosol-forming substrate during blowing by a user.
[00156] By preventing or inhibiting the combustion activation of the blind combustible heat source, and therefore preventing or inhibiting excessive temperature increases in the aerosol forming substrate, combustion can be advantageously avoided or pyrolysis of the aerosol forming substrate under intense blowing regimes. Furthermore, the impact of a user's puff regimen on the main aerosol can be advantageously minimized or reduced.
[00157] The inclusion of a blind combustible heat source can also, and advantageously, inhibit or prevent combustion and decomposition products and other materials formed during ignition and combustion of the blind combustible heat source from entering the air drawn through the articles for smoking, according to the invention, while using them. This is particularly advantageous when the blind combustible heat source comprises one or more additives to aid in the ignition or combustion of the blind combustible heat source.
Smoking articles according to the invention comprising a blind combustible heat source comprise one or more air inlets downstream of the rear of the combustible heat source. As described above, smoking articles according to the invention comprising a blind combustible heat source may comprise one or more of: one or more first air inlets around the periphery of the aerosol former; one or more second air inlets between the rear of the combustible heat source and the aerosol forming substrate; and one or more third air inlets downstream of the aerosol-forming substrate.
[00159] In smoking articles according to the invention, which comprise blunt combustible heat sources, heat transfer from the blunt combustible heat source to the aerosol-forming substrate occurs mainly by conduction, and heating of the substrate aerosol former by forced convection is minimized or reduced. This can advantageously help to minimize or reduce the impact of the user's puff regimen on the main aerosol composition of smoking articles in accordance with the invention.
[00160] In smoking articles according to the invention which comprise a blind combustible heat source, it is particularly important to optimize the conductive heat transfer between the combustible heat source and the aerosol forming substrate. In these embodiments, the inclusion of one or more of: an enclosure comprising a layer of thermally conductive material; a first heat-conducting element; and a second heat-conducting element is particularly preferred. This advantageously helps to ensure sufficiently high conductive heat transfer from the blind combustible heat source to the aerosol forming substrate to provide an acceptable aerosol.
[00161] It should be noted that smoking articles according to the invention may comprise blind combustible heat sources comprising one or more closed or blocked passages through which air cannot be drawn in by inhalation by the user.
[00162] For example, smoking articles according to the invention may comprise blind combustible heat sources comprising one or more closed passages extending from the front face at the upstream end of the combustible heat source only part of the path along the length of the blind combustible heat source.
[00163] The inclusion of one or more closed air passages increases the surface area of the blind combustible heat source that is exposed to oxygen in the air and can advantageously facilitate ignition and continuous combustion of the blind combustible heat source.
[00164] Preferably, the combustible heat source is a carbonaceous heat source. As used herein, the term "carbonaceous" is used to describe a combustible heat source that comprises carbon. Preferably, carbonaceous combustible heat sources for use in smoking articles in accordance with the invention have a carbon content of at least about 35 percent, more preferably at least about 40 percent, most preferably still of at least 45 percent by dry weight of the combustible heat source.
[00165] In some embodiments, combustible heat sources according to the invention are carbon-based combustible heat sources. As used herein, the term "carbon-based heat source" is used to describe a heat source comprised primarily of carbon.
[00166] Carbon-based combustible heat sources for use in smoking articles accordingly have a carbon content of at least about 50%. For example, carbon-based combustible heat sources for use in smoking articles according to the invention may have a carbon content of at least about 60 percent, more preferably at least about 70 percent or at least about 70 percent. less about 80 percent of the dry weight of the carbon-based fuel heat source.
Smoking articles according to the invention may comprise carbonaceous combustible heat sources formed from one or more suitable carbon-containing materials.
[00168] If desired, one or more binders can be combined with the one or more carbon-containing materials. Preferably, the one or more binders are organic binders. Suitable known organic binders include, but are not limited to, gums (eg, guar gum), modified celluloses and cellulose derivatives (eg, methyl cellulose, carboxymethylcellulose, hydroxypropylcellulose and hydroxypropyl methylcellulose), wheat flour, starches , sugars, vegetable oils and combinations thereof.
[00169] In a preferred embodiment, the fuel heat source is formed from a mixture of carbon powder, modified cellulose, wheat flour and sugar.
[00170] In place of or in addition to one or more binders, combustible heat sources for use in smoking articles according to the invention may comprise one or more additives in order to improve the properties of the combustible heat source. Suitable additives include, but are not limited to, additives to promote the consolidation of the combustible heat source (eg, sintering aids), additives to promote the ignition of the combustible heat source (eg, oxidizers such as perchlorates, chlorates, nitrates, peroxides, permanganates, zirconium and combinations thereof), additives to promote combustion of the combustible heat source (eg potassium and potassium salts such as potassium citrate) and additives to promote the decomposition of one or more gases produced by combustion of the combustible heat source (eg catalysts such as CuO, Fe2O3 and Al2O3).
[00171] If smoking articles according to the invention comprise a first barrier coating provided on the rear face of the combustible heat source, such additives may be incorporated into the combustible heat source prior to or after application of the first barrier coating to the rear face of the combustible heat source.
[00172] In certain preferred embodiments, the combustible heat source is a carbonaceous combustible heat source comprising carbon and at least one ignition aid. In a preferred embodiment, the combustible heat source is a carbonaceous combustible heat source comprising carbon and at least one ignition aid, as described in WO-A1-2012/164077.
[00173] As used in this document, the term "ignition aid" is used to describe a material that releases oxygen and/or energy during ignition of the combustible heat source, in which the rate of release of oxygen and/or energy by the material is not limited by ambient oxygen diffusion. In other words, the rate of release of oxygen and/or energy by the material during ignition of the combustible heat source is largely independent of the rate at which ambient oxygen can reach the material. As used in this document, the term "ignition aid" is also used to describe an elemental metal that releases energy during ignition of the combustible heat source, where the ignition temperature of the elemental metal is less than about 500° C and the heat of combustion of the elemental metal is at least about 5 kJ/g.
As used herein, the term "ignition aid" does not include alkali metal salts of carboxylic acids (such as alkali metal citrate salts, alkali metal acetate salts and alkali metal succinate salts), metal halide salts alkali metal (such as alkali metal chloride salts), alkali metal carbonate salts or alkali metal phosphate salts, which are believed to modify carbon combustion. Even when present in a large amount relative to the total weight of the fuel heat source, such alkali metal burning salts do not release enough energy during ignition of a fuel heat source to produce an acceptable aerosol during the first few puffs.
[00175] For example, combustible heat sources according to the invention may include one or more oxidizing agents that decompose to release oxygen upon ignition of the first part of the combustible heat sources. Fuel heat sources according to the invention may comprise organic oxidizing agents, inorganic oxidizing agents or a combination thereof.
[00176] Examples of suitable oxidizing agents include, but are not limited to: nitrates such as potassium nitrate, calcium nitrate, strontium nitrate, sodium nitrate, barium nitrate, lithium nitrate, aluminum nitrate and iron nitrate; nitrites; other organic and inorganic nitro compounds; chlorates such as, for example, sodium chlorate and potassium chlorate; perchlorates such as, for example, sodium perchlorate; chlorides; bromates, such as, for example, sodium bromate and potassium bromate; perbromates; bromides; borates, such as, for example, sodium borate and potassium borate; ferrates, such as, for example, barium ferrate; ferrite; manganates, such as, for example, potassium manganate; permanganates, such as, for example, potassium permanganate; organic peroxides, such as, for example, benzoyl peroxide and acetone peroxide; inorganic peroxides, such as, for example, hydrogen peroxide, strontium peroxide, magnesium peroxide, calcium peroxide, barium peroxide, zinc peroxide and lithium peroxide; superoxides, such as, for example, potassium superoxide and sodium superoxide; iodates; periodates; iodides; sulfates; sulfites; other sulfoxides; phosphates; phosphinates; phosphites; and phosphanates.
[00177] While advantageously improving the ignition and combustion properties of the carbonaceous fuel heat source, the inclusion of ignition and combustion additives can give rise to undesirable combustion and decomposition products during consumption of the article to smoke. For example, the decomposition of nitrates included in the combustible heat source to help ignite it can result in the formation of nitrogen oxides.
[00178] The inclusion of a first substantially non-combustible air-impermeable barrier between the rear face of the combustible heat source and the aerosol-forming substrate can substantially and advantageously prevent or inhibit such decomposition and reaction products from entering the air drawn through the smoking articles according to the invention.
[00179] If the smoking articles according to the invention comprise an unblinded combustible heat source, the inclusion of a second substantially non-combustible air-impermeable barrier between the one or more air flow channels and the source of non-blinding combustible heat can substantially and advantageously inhibit or prevent such reaction products from entering the air drawn into smoking articles in accordance with the invention through the one or more air-conforming air flow channels puff passes through the one or more airflow channels.
[00180] Carbonaceous combustible heat sources for use in smoking articles, according to the invention, can be prepared as described within the art known to individuals moderately skilled in the art.
[00181] Carbonaceous combustible heat sources for use in smoking articles, according to the invention, are preferably formed by mixing one or more carbon-containing materials with one or more binders and other additives, where included, and by preforming the mixture into a desired shape. The mixture of one or more carbon-containing materials, one or more binders and other additional additives can be preformed into a desired shape using any known method of forming ceramics, such as slip casting, extrusion, injection molding and compaction or mold pressing. In certain preferred embodiments, the mixture is preformed into a desired shape through pressing or extrusion or a combination thereof.
[00182] Preferably, the mixture of one or more carbon-containing materials, one or more binders and other additives is preformed into an elongated rod. However, it should be noted that the mixture of one or more carbon-containing materials, one or more binders and other additives can be preformed into other desired shapes.
[00183] After formation, particularly after extrusion, the elongated rod or other desired shape is preferably dried to reduce its wet content and then pyrolyzed in a non-oxidizing atmosphere at a temperature sufficient to carbonize the one or more binders, where present , and substantially eliminate any volatile compounds in the elongated rod or other shape. The elongated rod, or other desired shape, is preferably pyrolyzed in a nitrogen atmosphere at a temperature between about 700°C and about 900°C.
[00184] In certain embodiments, at least one metal nitrate salt is incorporated into the fuel heat source by including at least one metal nitrate precursor in the mixture of one or more carbon-containing materials, one or more binders and other additives. The at least one metal nitrate precursor is then converted in-situ to the at least one metal nitrate salt by treating the cylindrical or otherwise pyrolyzed rod with an aqueous solution of nitric acid. In one embodiment, the combustible heat source comprises at least one metal nitrate salt having a thermal decomposition temperature of less than about 600°C, more preferably less than about 400°C. Preferably, at least one metal nitrate salt has a decomposition temperature between about 150°C and about 600°C, more preferably between about 200°C and about 400°C.
[00185] In preferred embodiments, exposure of the combustible heat source to a conventional lighter flame or any other means of ignition should cause at least one metal nitrate salt to decompose and release oxygen and energy. Such decomposition causes an initial rise in the temperature of the combustible heat source and also assists in igniting the combustible heat source. After the decomposition of at least one metal nitrate salt, the combustible heat source preferably continues combustion at a lower temperature.
[00186] The inclusion of at least one metal nitrate salt advantageously results in the ignition of the combustible heat source being internally initiated, and not just at a point on the surface of the same. Preferably, the at least one metal nitrate salt is present in the fuel heat source in amounts of from about 20 percent dry weight to about 50 percent dry weight of the fuel heat source.
[00187] In other embodiments, the combustible heat source comprises at least one peroxide or superoxide that actively evolves at a temperature below about 60°C, more preferably at a temperature below about 400°C.
[00188] Preferably, the at least one peroxide or superoxide actively evolves oxygen at a temperature between about 150°C and about 600°C, more preferably at a temperature between about 200°C and about 400 °C, more preferably at a temperature of about 350 °C.
[00189] In use, exposure of the combustible heat source to a yellow flame of a conventional lighter or any other means of ignition must cause the at least one peroxide or superoxide to decompose and release oxygen. This causes an initial rise in the temperature of the combustible heat source and also assists in igniting a combustible heat source. After the decomposition of at least one peroxide or superoxide, the combustible heat source preferably continues its combustion at a lower temperature.
[00190] The inclusion of at least one peroxide or superoxide advantageously results in the ignition of the combustible heat source being initiated internally, and not just at a point on its surface.
The combustible heat source preferably has porosity between about 20 percent and about 80 percent, more preferably between about 20 percent and 60 percent. Where the combustible heat source comprises at least one metal nitrate salt, this advantageously allows oxygen to diffuse into the mass of the combustible heat source at a rate sufficient to maintain combustion while at least one metal nitrate salt decomposes and combustion proceeds. Even more preferably, the combustible heat source has a porosity of between about 50 percent and about 70 percent, more preferably between about 50 percent and about 60 percent, as measured by, for example, porosimetry. of mercury or helium pycnometry. The required porosity can be easily achieved during the production of the combustible heat source using conventional technology and methods.
[00192] Advantageously, carbonaceous combustible heat sources for use in smoking articles according to the invention have bulk density between about 0.6 g/cm3 and about 1 g/cm3.
Preferably, the combustible heat source has a mass between about 300mg and about 500mg, more preferably between about 400mg and about 450mg.
[00194] Preferably, smoking articles according to the invention comprise an aerosol forming substrate comprising at least one aerosol former and a material capable of releasing volatile compounds in response to heating. The aerosol forming substrate may contain additives and ingredients including, but not limited to, humectants, flavors, binders and mixtures thereof.
[00195] Preferably, the aerosol forming substrate comprises nicotine. More preferably, the aerosol forming substrate comprises tobacco.
[00196] At least one aerosol former may be any suitable known compound or mixture of compounds which, in use, facilitates the formation of a dense and stable aerosol and which is substantially resistant to thermal degradation at the operating temperature of the smoking article. Suitable aerosol formers are well known in the art and include, for example, polyhydric alcohols, esters of polyhydric alcohols such as glycerol mono-, dior triacetate and aliphatic esters of mono-, di- or polycarboxylic acids , such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formers for use in smoking articles in accordance with the invention are polyhydric alcohols or mixtures thereof, such as triethylene glycol, 1,3-butanediol and, most preferably, glycerin.
[00197] The material capable of emitting volatile compounds in response to heating can be a plant-based material charge. Preferably, the material capable of emitting volatile compounds in reaction to heating is a plant-based material charge, more preferably a homogenized plant-based material. For example, the aerosol forming substrate can comprise one or more plant-derived materials, including, but not limited to: tobacco; tea, for example green tea; mint; blond; eucalyptus; basil; saves; verbena; and tarragon.
[00198] Preferably, the material capable of emitting the volatile compounds in response to heating is a tobacco-based material charge, more preferably a tobacco-based homogenized material charge.
[00199] The aerosol forming substrate may be in the form of a plug or segment comprising a material capable of emitting volatile compounds in response to heating circumscribed by a paper or other envelope. As noted above, if an aerosol-forming substrate is in the form of such a plug or segment, the entire plug or segment, including any housing, will be considered to be the aerosol-forming substrate.
Preferably, the aerosol forming substrate has a length of between about 5 mm and about 20 mm, more preferably between about 8 mm and about 12 mm.
[00201] In preferred embodiments, the aerosol forming substrate comprises a plug of tobacco-based material wrapped in a plug wrap. In specifically preferred embodiments, the aerosol forming substrate comprises a plug of homogenized tobacco-based material wrapped in a plug wrap.
Smoking articles according to the invention preferably comprise a mouth downstream of the aerosol-forming substrate. The mouth is located at the proximal end of the smoking article.
[00203] Preferably, the mouth is of low filtration efficiency, more preferably of very low filtration efficiency. The mouth can be a segment or a single component mouth. Alternatively, the mouth can be a multi-segment or multi-component mouth.
[00204] The mouth may comprise a filter comprising one or more segments comprising suitable known filtration materials. Suitable filtration materials are known in the art and include, but are not limited to, cellulose acetate and paper. Alternatively or additionally, the mouth may comprise one or more segments comprising absorbents, adsorbents, flavorings and other additives and aerosol modifiers or combinations thereof.
Smoking articles according to the invention may further comprise an element for directing the air flow between the aerosol forming substrate and the mouth. In these embodiments, the air flow directing member defines an air flow path and directs air from at least one air inlet along the air flow path to the mouth end of the smoking article.
[00206] The at least one air inlet is preferably provided between a downstream end of the aerosol forming substrate and a downstream end of the airflow directing element. The air flow path preferably comprises a first portion extending longitudinally from at least one air inlet to the aerosol forming substrate and a second portion extending longitudinally from the aerosol forming substrate toward the mouth end of the article to smoke. In use, air drawn from the smoking article through at least one air inlet passes along the first part of the air flow path to the aerosol-forming substrate and then downstream towards the mouth end of the article. to smoke along the second part of the airflow path.
[00207] The air flow directing element may comprise a substantially air-impermeable hollow body with open end. In such embodiments, the exterior of the open-ended, substantially air-impermeable hollow body defines one between the first portion of the air flow path and the second portion of the air flow path and the interior of the hollow, substantially air-impermeable body. and the open end defines the other to the first portion of the air flow path and the second portion of the air flow path. Preferably, the exterior of the hollow, substantially air-tight, open-end body defines the first part of the air flow path, and the interior of the hollow, substantially air-impermeable, open-end body defines the second part of the air flow path. air.
[00208] In a preferred embodiment, the substantially air-tight, open-ended hollow body is a cylinder, preferably a straight circular cylinder.
[00209] In another preferred embodiment, the substantially air-tight and open-ended hollow body is a truncated cone, preferably a straight circular truncated cone.
[00210] The substantially air-tight, open-ended hollow body can abut an aerosol-forming substrate. Alternatively, the substantially air-tight, open-ended hollow body may extend into the aerosol-forming substrate.
[00211] The substantially air-impermeable hollow body may be formed of one or more suitable air-impermeable materials that are substantially thermally stable at the temperature of the aerosol generated by the transfer of heat from the fuel heat source to the aerosol-forming substrate. Suitable materials are known in the art and include, but are not limited to, cardboard, plastic, ceramic and combinations thereof.
[00212] Smoking articles according to the invention preferably further comprise a transfer element or spacer element between the aerosol-forming substrate and the mouth.
[00213] The transfer element may abut one or both of the aerosol forming substrate and the mouth. Alternatively, the transfer element may be spaced one or both of the aerosol forming substrate and the mouth apart.
[00214] The inclusion of a transfer element allows, and advantageously, the cooling of the aerosol generated by the transfer of heat from the fuel heat source to the aerosol forming substrate. The inclusion of a transfer element also advantageously allows the overall length of smoking articles according to the invention to be adjusted to a desired value, for example to a length similar to that of conventional cigarettes, by a suitable choice of length of the transfer element.
[00215] The transfer element may have a length of between about 7 mm and about 50 mm, for example a length of between about 10 mm and about 45 mm or between about 15 mm and about 30 mm . The transfer element may have other lengths depending on the overall desired length of the smoking article and the presence and length of other components within the smoking article.
[00216] Preferably, the transfer element comprises at least one hollow tubular body with open ends. In such embodiments, during use, air drawn through the smoking article passes through the at least one hollow tubular body with open ends as it passes downstream through the smoking article from the aerosol forming substrate to the proximal end thereof. .
[00217] The transfer element may comprise at least one open-ended hollow tubular body formed from one or more materials substantially thermosetting at the temperature of the aerosol generated by the transfer of heat from the combustible heat source to the aerosol forming substrate. Suitable materials are known in the art and include, but are not limited to, paper, paperboard, plastics such as cellulose acetate, ceramics and combinations thereof.
[00218] Alternatively or additionally, smoking articles according to the invention may comprise an aerosol cooling element or thermal energy exchanger between aerosol forming substrate and the mouth. The aerosol cooling element may comprise a plurality of longitudinally extending channels.
[00219] The aerosol cooling element may comprise a grouped plate of material selected from a group consisting of sheet metal, polymeric material and substantially non-porous paper or paperboard. In certain embodiments, aerosol cooling element may comprise a grouped plate of material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinylchloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA ), cellulose acetate (CA) and aluminum foil.
[00220] In certain preferred embodiments, the aerosol cooling element may comprise a grouped plate of biodegradable polymeric material, such as polylactic acid (PLA) or a grade of Mater-Bi® (a family of commercially available starch-based copolyesters ).
Smoking articles according to the invention may comprise one or more aerosol modifying agents downstream of the aerosol forming substrate. For example, one or more of the mouth, transfer element and aerosol cooling element of smoking articles according to the invention may comprise one or more aerosol modifying agents.
Suitable aerosol modifying agents include, but are not limited to: flavorings; and chemoesthetic agents.
[00223] As used herein, the term "flavoring" is used to describe any agent which, in use, imparts a taste and/or aroma to an aerosol generated by the aerosol forming substrate of the smoking article.
[00224] As used in this document, the term "chemoesthetic agent" is used to describe any agent that, in use, is perceived in a user's oral or olfactory cavities by means other than, or in addition to, perception through the taste receptors or olfactory receptor cells. The perception of chemoaesthetic agents is typically through a "trigeminal reaction," or through the trigeminal nerve, the glossopharyngeal nerve, the vagus nerve, or some combination of these. Typically, chemoaesthetic agents are perceived as hot, spicy, refreshing, or soothing sensations.
Smoking articles according to the invention may comprise one or more aerosol modifying agents which are both a flavoring and a chemoesthetic agent downstream of the aerosol forming substrate. For example, one or more of the mouth, transfer element and aerosol cooling element of smoking articles according to the invention may comprise menthol or other flavoring which provides a refreshing chemoaesthetic effect.
Smoking articles according to the invention can be assembled using known methods and machinery.
[00227] The invention will be described below, by way of example only, with reference to the attached drawings, in which:
[00228] Figure 1 shows a perspective view of a first blind combustible heat source for inclusion in a smoking article, according to the invention;
[00229] Figure 2 shows a perspective view of a second blind combustible heat source for inclusion in a smoking article, according to the invention; and
[00230] Figure 3 shows a schematic longitudinal cross-section of a smoking article, according to a first embodiment of the invention, comprising the blind combustible heat source shown in Figure 1.
[00231] The first blind combustible heat source 2 shown in Figure 1 is comprises a front part 2a of the substantially constant circular cross section and a rear part 2b of the substantially constant circular cross section. As shown in Figure 1, the front part 2a of the blind fuel heat source 2 has reduced diameter compared to the back part 2b of the blind fuel heat source. The first blind combustible heat source 2 shown in Figure 1 has a substantially T-shaped longitudinal cross-section.
[00232] The second blind combustible heat source 4 shown in Figure 2 comprises a front part 4a of the generally circular cross section and a rear part 4b of the substantially constant circular cross section. As shown in Figure 2, six circumferentially spaced longitudinal grooves 6 of reduced diameter compared to the rear part 4b of the second blind heat source 4 are provided on the periphery of the front part 4a of the second blind fuel heat source 4. The front part 4a of the second blind combustible heat source 4 shown in Figure 2 has a substantially constant star or sprocket cross section.
[00233] The smoking article 8, according to the first embodiment of the invention shown in Figure 3, comprises the first blind combustible heat source 2 shown in Figure 3, an aerosol forming substrate 10, a transfer element 12, a aerosol coolant element 14, a spacer element 16 and a mouth 18 in contiguous coaxial alignment.
[00234] The first blind combustible heat source 2 has a front face 20 and an opposite rear face 22 and is located at the distal end of the smoking article 8. As shown in Figure 3, a first substantially non-combustible air-impermeable barrier 24 in the form of an aluminum foil disk is provided between the rear face 22 of the first blind fuel heat source 2 and the aerosol forming substrate 10. The first barrier 24 is applied to the rear face 22 of the first blind fuel heat source 2 pressing the aluminum foil disc onto the rear face 22 of the first blunt fuel heat source 2 and abutting the rear face 22 of the first blunt fuel heat source 2a and the aerosol forming substrate 10.
[00235] The aerosol forming substrate 10 is located immediately downstream of the first barrier 24 applied to the rear face 22 of the first blind fuel heat source 2. The aerosol forming substrate 10 comprises a cylindrical plug of homogenised material based on tobacco 26 including an aerosol former such as glycerin wrapped in a plug wrap 28.
The transfer element 12 is located immediately downstream of the aerosol forming substrate 10 and comprises a hollow cylindrical tube of cellulose acetate with an open end 30.
The aerosol cooler element 14 is located immediately downstream of the transfer element 12 and comprises a grouped sheet of biodegradable polymeric material such as, for example, polylactic acid.
The spacer element 16 is located immediately downstream of the aerosol refrigeration element 14 and comprises a hollow cylindrical tube with an open end of cardboard or paper 32.
The mouth 18 is located immediately downstream of the spacer element 16. As shown in Figure 3, the mouth 18 is located at the proximal end of the smoking article 8 and comprises a cylindrical plug of suitable filtration material 34 as per example, cellulose acetate fiber with very low filtration efficiency, wrapped around a filter plug casing 36.
[00240] As shown in Figure 1, the smoking article 8 comprises a first heat-conducting element 38 of suitable material such as aluminum foil around and in direct contact with the rear part 2b of the first combustible heat source blind 2 and a front 10a of the aerosol-forming substrate 10. The smoking article 8 according to the first embodiment of the invention shown in Figure 3, the aerosol-forming substrate 10 extends downstream beyond the first heat-conducting element 38. That is, the first heat-conducting element 38 is not around or in direct contact with a backside of the aerosol forming substrate 10. However, it should be noted that in other embodiments of the invention (not shown), the first heat-conducting element 38 may be around or in contact with the entire length of the aerosol-forming substrate 10.
[00241] As shown in Figure 3, the front 2a and the rear 2b of the first blind fuel heat source 2, aerosol forming substrate 10, transfer element 12, aerosol cooling element 14, spacer element 16 and mouth 18 are surrounded by a wrapper 40 of heat-insulating material such as cigarette paper.
[00242] The casing 40 overlaps the first heat-conducting element 38 and is in indirect contact with the rear part 2a of the combustible heat source 2. As shown in Figure 3, the entire front part 2b of the first combustible heat source 2 of reduced diameter compared to the rear part 2b of the fuel heat source 2, the casing 40 is radially spaced from the entire front part 2a of the fuel heat source by the air gap 42.
[00243] The smoking article may further comprise a strip of tip paper (not shown) circumscribing a portion of the downstream end of the wrapper 40.
[00244] The smoking article 8 also comprises a second heat-conducting element 44 of suitable material such as, for example, aluminum foil around a front part 2a and a back part 2b of the first blind combustible heat source 2 and the total length of the aerosol forming substrate 10 and the total length of the transfer element 12. As shown in Figure 3, the second heat-conducting element 44 overlaps and is in direct contact with an upstream end portion of the housing 40.
[00245] A plurality of perforations 46 are provided in the casing 40 and in the second heat conducting element around the front 2a of the combustible heat source 2.
[00246] The smoking article 8, according to the first embodiment of the invention, further comprises one or more first air inlets 48 around the periphery of the aerosol-forming substrate 10. As shown in Figure 3, a circumferential arrangement of the first air inlets 48 is provided in the plug housing 28 of the aerosol forming substrate 10, the housing 40 and the second heat-conducting element 44 to admit fresh air (represented by the dotted arrows in Figure 3) into the interior of the aerosol forming substrate. aerosol 10.
[00247] When in use, a user lights the front part 2a of the first blind combustible heat source 2 of the smoking article 8 according to the first embodiment of the invention and then brings it into the mouth 18. The plurality of perforations 46 provided in the casing 40 and in the second heat-conducting element around the front part 2a of the first blind fuel heat source 2 ensures a sufficient supply of oxygen for the front part 2a of the first blind fuel heat source 2 to maintain its combustion.
[00248] When the user inhales into mouth 18, fresh air (shown by the dotted arrows in Figure 3) is drawn into the aerosol forming substrate 10 of the smoking article 8 through the first air inlets 48. The front 10a of the aerosol forming substrate 10 is heated by conduction through the back 22 of the first blind fuel heat source 2 and the first barrier 24 and the first heat conducting element 38.
[00249] Heating the aerosol-forming substrate 10 by conduction releases glycerin and other volatile and semi-volatile compounds from the plug of the homogenized tobacco-based material 26. The compounds released from the aerosol-forming substrate 10 form an aerosol that enters the air drawn into the aerosol-forming substrate 10 of the smoking article 8 through the first air inlets 48 as it flows through the aerosol-forming substrate 10. The entrained air and entrained aerosol (shown by dotted arrows in Figures 3) passes , in a downstream direction, through the interior of the hollow open-end cellulose acetate tow tube 30 of the transfer element 12, the aerosol cooling element 14 and the spacer element 16, where they cool and condense. The chilled inhaled air and entrained aerosol pass downstream through mouth 18 and are delivered to the user through the proximal end of the smoking article 8 in accordance with the first embodiment of the invention. The first substantially non-combustible air-tight barrier 24 on the rear face 22 of the first blind combustible heat source 2 isolates the first blind combustible heat source 2 from the air drawn through the smoking article 8 so that, in use , the air drawn through the smoking article 8 does not come into direct contact with the first blind combustible heat source 2.
[00250] In use, the second heat-conducting element 44 retains heat within the smoking article 8 to help maintain the temperature of the heat-conducting element 38 during smoking. This, in turn, aids in maintaining the temperature of the aerosol forming substrate 10 so as to facilitate continued and improved aerosol delivery. In addition, the second heat-conducting element 44 transfers heat along the aerosol-forming substrate 10, beyond the downstream end of the first heat-conducting element 38 so that heat is dispersed by a larger volume of the aerosol-forming substrate 10 This helps to provide more consistent blow-by-puff aerosol delivery.
[00251] The air gap 42 between the housing 40 and the front part 2a of the first blind combustible heat source 2 isolates the front part 2a of the first blind combustible heat source 2 and thus reduces the surface temperature of the smoking article 8 around the front part 2a of the first blind fuel heat source 2.
[00252] A smoking article according to a second embodiment of the invention (not shown) with a construction very similar to the smoking article according to the first embodiment of the invention shown in Figure 3. However, the smoking article of in accordance with the second embodiment of the invention, comprises the second blind combustible heat source shown in Figure 2. In the smoking article according to the second embodiment of the invention, the wrapper 40 is radially spaced by six circumferentially spaced longitudinal grooves. provided on the periphery of the front part 4a of the second blind fuel heat source 4, which have a reduced diameter compared to the back part 4b of the second blind fuel heat source 4, by an air gap.
[00253] The smoking articles according to the invention are assembled manually using first blind combustible heat sources of the type shown in Figure 1, having the dimensions indicated in Table 1. For comparison purposes, the smoking articles of same construction and dimensions are assembled by hand using blind fuel heat sources of the same composition and substantially constant circular cross section with dimensions indicated in Table 1.
Table 1
[00254] As shown in Table 1, due to the reduced diameter of the front of the blind fuel heat source compared to the back of the blind fuel heat source, in smoking articles according to the invention of Example 1, the casing is radially spaced from the entire front of the combustible heat source blinded by a 1.0mm air gap. In contrast, in the smoking articles of the comparative example, there is no air gap between the wrapper and the front of the blind combustible heat source.
The surface temperature around the combustible heat sources of the smoking articles according to the invention of Example 1 and the smoking articles of the comparative example is tested. Ten Whatman filters are placed on top of a standard filter holder. The blunt combustible heat sources of the smoking articles are lit with a yellow flame lighter. The flame is removed when lighting propagation occurs. The color on the surface of the blunt fuel heat sources changes after ignition due to the downstream movement of a blazing front from the front end to the rear end of the blunt fuel heat sources. Thirty seconds after the deflagration front has reached the rear end of the blind fuel heat sources, the smoking articles are placed horizontally over the ten Whatman filters. Smoking articles are left in Whatman filters for 10 minutes. The Whatman filters are then removed from the filter holder and the first (top), third, sixth and tenth (bottom) Whatman filters are analyzed for burnout occurrence and depth of heat penetration.
[00256] The first, third, sixth and tenth filters for the smoking article of the comparative example are all marked. In contrast, the third, sixth and tenth filters for the smoking article according to the invention of Example 1 are not marked.
[00257] Smoking articles according to the invention are assembled manually using second blind combustible heat sources of the type shown in Figure 1, having the dimensions indicated in Table 2. For comparison purposes, smoking articles from same construction and dimensions are assembled by hand using the blind fuel heat sources of the same composition and substantially constant circular cross section with the dimensions indicated in Table 2.
Table 2
[00258] As shown in Table 1, due to the reduced diameter of the plurality of circumferentially spaced longitudinal grooves provided on the periphery of the front of the blind fuel heat source compared to the back of the blind fuel heat source, in smoking articles according to the invention of Example 2, the casing is radially spaced from the front of the combustible heat source blinded by an air gap of 0.5 mm. In contrast, in the smoking articles of the comparative example, there is no air gap between the wrapper and the front of the blind combustible heat source.
[00259] The surface temperature around the combustible heat sources of the smoking articles according to the invention of Example 2 and the smoking articles of the comparative example is tested. Ten Whatman filters are placed on top of a standard filter holder. The blunt combustible heat sources of the smoking articles are lit with a yellow flame lighter. The flame is removed when lighting propagation occurs. The color on the surface of the blunt fuel heat sources changes after ignition due to the downstream movement of a blazing front from the front end to the rear end of the blunt fuel heat sources. Thirty seconds after the deflagration front has reached the rear end of the blind fuel heat sources, the smoking articles are placed horizontally over the ten Whatman filters. Smoking articles are left in Whatman filters for 10 minutes. The Whatman filters are then removed from the filter holder and the first (top), third, sixth and tenth (bottom) Whatman filters are analyzed for burnout occurrence and depth of heat penetration.
[00260] The first, third, sixth and tenth filters for the smoking article of the comparative example are all marked. In contrast, the sixth and tenth filters for the smoking article according to the invention of Example 2 are not marked.
[00261] The results of Examples 1 and 2 demonstrate that the inclusion of an air gap of at least about 0.5 mm between all or part of the front of the fuel heat source and the casing advantageously reduces the temperature surface of smoking articles in accordance with the invention.
[00262] The embodiments and examples described above illustrate, but do not limit, the invention. Other embodiments of the invention may be carried out and it is understood that the specific embodiments and examples described herein are not to be a limiting factor.

权利要求:
Claims (16)
[0001]
1. A smoking article (8) comprising: a combustible heat source (2, 4) with a front (2a, 4a) and a rear (2b, 4b) portion; an aerosol forming substrate (10) downstream of the rear (2b, 4b) of the combustible heat source; and a casing (40) circumscribing the front (2a, 4a) and rear (2b, 4b) of the combustible heat source (2, 4), wherein the casing (40) is in contact with the rear (2b) , 4b) of the combustible heat source (2, 4) characterized by the fact that all or part of the front part (2a, 4a) of the combustible heat source (2, 4) has a reduced diameter compared to the rear part (2b , 4b) of the combustible heat source (2, 4) so that the casing (40) is radially spaced from all or part of the front (2a, 4a) of the combustible heat source (2, 4) by a gap of air (42) of at least about 0.5 mm.
[0002]
2. An article for smoking according to claim 1, characterized in that the casing is radially spaced from all or part of the front of the combustible heat source by an air gap between about 0.5 mm and about 1.5 mm.
[0003]
3. Smoking article (8) according to claim 1 or 2, characterized in that the casing (40) is radially spaced at least about 50% from the front of the combustible heat source (2) by the gap of air.
[0004]
4. Smoking article (8), according to any one of claims 1 to 3, characterized in that the front part (2a) of the fuel heat source (2) has a reduced diameter compared to the rear part ( 2b) of the combustible heat source (2) so that the casing (40) is radially spaced from the entire front (2a) of the combustible heat source (2) by the air gap (42).
[0005]
A smoking article according to any one of claims 1 to 3, characterized in that the front (4a) of the combustible heat source (4) comprises a plurality of circumferentially spaced longitudinal grooves (6) of reduced diameter compared to the rear (4b) of the combustible heat source (4).
[0006]
A smoking article according to any one of claims 1 to 5, characterized in that the wrapper comprises one or more layers of heat-conducting material.
[0007]
7. A smoking article, according to claim 6, characterized in that the casing comprises one or more layers of aluminium.
[0008]
8. Smoking article (8), according to any one of claims 1 to 7, characterized in that the casing (40) comprises one or more layers of heat-insulating material.
[0009]
9. A smoking article (8) according to claim 8, characterized in that the wrapper (40) comprises one or more layers of paper.
[0010]
10. A smoking article according to any one of claims 1 to 9, characterized in that the casing comprises a radially inner layer of heat-insulating material and a radially outer layer of heat-conducting material.
[0011]
11. Smoking article (8) according to any one of claims 1 to 10, characterized in that one or more air inlets (46) are provided in the housing (40) around the front part (2a) of the combustible heat source (2).
[0012]
12. A smoking article (8) according to any one of claims 1 to 11, characterized in that the rear (2b) of the combustible heat source (2) has substantially the same diameter as the aerosol forming substrate ( 10).
[0013]
A smoking article (8) according to any one of claims 1 to 12, characterized in that the combustible heat source (2, 4) is a blind combustible heat source (2, 4).
[0014]
A smoking article according to any one of claims 1 to 12, characterized in that one or more longitudinal air flow channels are provided through the combustible heat source.
[0015]
15. The smoking article of claim 14, further comprising a non-combustible substantially airtight barrier between the combustible heat source and the one or more air flow channels.
[0016]
16. A smoking article (8) according to any one of claims 1 to 15, characterized in that it further comprises a substantially airtight non-combustible barrier (24) between the rear portion (2b) of the source of combustible heat (2) and the aerosol forming substrate (10).

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同族专利:

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公开号 | 公开日

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UA118973C2|2019-04-10|

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US20160316816A1|2016-11-03|

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MX2016008656A|2016-10-03|

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JP6643232B2|2020-02-12|

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EP3089606A1|2016-11-09|

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WO2015101595A1|2015-07-09|

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PH12016500545A1|2016-06-13|

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CN105828647A|2016-08-03|

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TW201531245A|2015-08-16|

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RU2016131365A|2018-02-07|

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JP2017500852A|2017-01-12|

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IL244711D0|2016-04-21|

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PH12016500545B1|2016-06-13|

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KR102301265B1|2021-09-14|

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RU2668859C2|2018-10-03|

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ES2663344T3|2018-04-12|

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CA2927704A1|2015-07-09|

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US10542776B2|2020-01-28|

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KR20160103981A|2016-09-02|

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AU2014375238A1|2016-04-21|

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SG11201605158PA|2016-07-28|

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AU2014375238B2|2019-01-31|

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PT3089606T|2018-06-01|

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EP3089606B1|2018-02-21|

---

BR112016012894A2|2017-08-08|

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TWI657755B|2019-05-01|

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AR098966A1|2016-06-22|

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PL3089606T3|2018-07-31|

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CN105828647B|2019-11-19|

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ZA201601974B|2017-04-26|

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CN112334023A|2018-07-12|2021-02-05|株式会社东亚产业|Heated aroma generating base material suitable for aromatic cigarette cartridge, heated aroma generating base body, aromatic cigarette cartridge provided with heated aroma generating base body, and method and device for manufacturing heated aroma generating base body|

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法律状态:
2020-02-11| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|

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2021-06-08| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|

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2021-08-10| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 29/12/2014, OBSERVADAS AS CONDICOES LEGAIS. |

优先权:

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申请号 | 申请日 | 专利标题

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EP13199811|2013-12-30|

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EP13199811.4|2013-12-30|

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PCT/EP2014/079364|WO2015101595A1|2013-12-30|2014-12-29|Smoking article comprising an insulated combustible heat source|

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