KR20220116493A - Combustible heat sources including ignition aids and binders - Google Patents

Abstract

A combustible heat source for an aerosol-generating article, the combustible heat source comprising: carbon; alkaline earth metal peroxide ignition aids; and a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether. Preferably, the at least one additional cellulose ether is selected from the group consisting of ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose.

Description

Combustible heat sources including ignition aids and binders

The present invention relates to an aerosol-generating article comprising a combustible heat source for an aerosol-generating article and a heatable heat source and an aerosol-forming substrate downstream of the combustible heat source.

A number of aerosol-generating articles in which tobacco is heated rather than combusted have been proposed in the art. One goal of such 'heated' aerosol-generating articles is to reduce known harmful smoke components of the type produced by the combustion and pyrolytic degradation of tobacco in conventional cigarettes.

Typically in heated aerosol-generating articles, the aerosol is used for heat transfer from a heat source, such as a chemical, electrical, or combustible heat source, to a physically separate aerosol-forming substrate, which may be located inside, around or downstream of the heat source. is caused by

In one known type of heated aerosol-generating article, the aerosol is generated by heat transfer from a combustible carbonaceous heat source to a physically separate aerosol-forming substrate comprising tobacco material located downstream of the combustible carbonaceous heat source. In use, volatile compounds are released from the tobacco material by heat transfer from the combustible carbonaceous heat source to the aerosol-forming substrate and are entrained in air drawn through the aerosol-generating article. The released compound condenses as it cools, forming an aerosol that is inhaled by the user.

Heat may be transferred from the combustible carbonaceous heat source to the aerosol-forming substrate by one or both of forced convection and conduction.

Around and with at least the rear portion of the combustible carbonaceous heat source and at least the front portion of the aerosol-forming substrate of the heated aerosol-generating article to ensure sufficient conductive heat transfer from the combustible carbonaceous heat source to the aerosol-forming substrate to obtain an acceptable aerosol; It is known to include heat-conducting elements in direct contact. For example, WO 2009/022232 A2 discloses a combustible carbonaceous heat source, an aerosol-forming substrate downstream of the combustible heat source, and heat conduction around and in contact with the rear portion of the combustible carbonaceous heat source and an adjacent front portion of the aerosol-forming substrate. A smoking article comprising the element is disclosed. In use, heat generated during combustion of the combustible carbonaceous heat source is transferred around the forward portion of the aerosol-forming substrate by conduction through bonding of the heat-conducting element to the downstream end of the combustible carbonaceous heat source.

The combustion temperature of a combustible heat source for use in a heated aerosol-generating article should not be so high as to result in combustion or thermal degradation of the aerosol-forming substrate during use of the heated aerosol-generating article. However, the combustion temperature of the combustible carbonaceous heat source must be high enough to generate sufficient heat to release sufficient volatile compounds from the aerosol-forming substrate to produce an acceptable aerosol, particularly during the initial puff.

A variety of combustible carbonaceous heat sources for use in heated aerosol-generating articles are known in the art.

When used in heated aerosol-generating articles, known combustible carbonaceous heat sources often do not generate sufficient heat after ignition to produce an acceptable aerosol during initial puffing.

When used in heated aerosol-generating articles, known combustible carbonaceous heat sources are often difficult to ignite. Failure to adequately ignite the combustible carbonaceous heat source of a heated aerosol-generating article may result in unacceptable aerosol delivery to the user.

It has been proposed to include oxidizing agents and other additives in combustible carbonaceous heat sources to improve ignition and combustion properties. For example, WO 2012/164077A1 discloses at least one selected from the group consisting of carbon, and metal nitrates, chlorates, peroxides, thermite materials, intermetallics, magnesium, zirconium, and combinations thereof having a pyrolysis temperature of less than about 600° C. A combustible heat source for smoking articles comprising the ignition aid of

Some ignition aids used in known combustible carbonaceous heat sources have been found to decompose upon exposure to environmental conditions during transportation and storage of combustible carbonaceous heat sources. For example, some ignition aids used in known combustible carbonaceous heat sources have been found to decompose upon exposure to atmospheric moisture during transportation and storage of combustible carbonaceous heat sources. Decomposition of ignition aids during transport and storage may disadvantageously make it more difficult to ignite known carbonaceous combustible heat sources, including ignition aid sources.

It would be desirable to provide a combustible carbonaceous heat source comprising an ignition aid that exhibits rapid ignition and mechanical integrity even after exposure to environmental conditions.

It would be desirable to provide a combustible carbonaceous heat source comprising an ignition aid that exhibits improved combustion properties compared to known combustible carbonaceous heat sources comprising the ignition aid.

The present invention relates to combustible heat sources for aerosol-generating articles. The combustible heat source may include carbon. The combustible heat source may include an ignition aid. The ignition aid may be an alkaline earth metal peroxide. The combustible heat source may include a binder. The binder may comprise carboxymethyl cellulose. The binder may comprise at least one additional cellulose ether. The binder may comprise a combination of carboxymethyl cellulose and at least one additional cellulose ether.

According to the present invention, there is provided a combustible heat source for an aerosol-generating article, the combustible heat source comprising: carbon; alkaline earth metal peroxide ignition aids; and a binder comprising at least one cellulose ether, wherein the binder does not comprise a non-flammable inorganic sheet silicate binder.

According to the present invention, there is provided a combustible heat source for an aerosol-generating article, the combustible heat source comprising: carbon; alkaline earth metal peroxide ignition aids; and a binder comprising at least one cellulose ether selected from the group consisting of ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose, wherein the binder comprises a non-flammable inorganic sheet silicate binder. I never do that.

According to the present invention, there is provided a combustible heat source for an aerosol-generating article, the combustible heat source comprising: carbon; alkaline earth metal peroxide ignition aids; and a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether.

According to the invention there is provided a combustible heat source according to the invention; and an aerosol-forming substrate downstream of the combustible heat source.

Surprisingly, the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether in the combustible heat source according to the invention can advantageously reduce the deterioration of the alkaline earth metal peroxide ignition aid as a result of exposure to environmental conditions. It turned out that there is

In particular, surprisingly, it was found that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether in the combustible heat source according to the invention can reduce the deterioration of the alkaline earth metal peroxide ignition aid as a result of exposure to high humidity. it turned out

Without wishing to be bound by theory, it is believed that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether reduces the overall hydrophilicity and hygroscopicity of the combustible heat source according to the present invention.

By reducing the deterioration of the alkaline earth metal peroxide ignition aid, the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether is advantageously used during transport and storage of the combustible heat source according to the invention chemically and physically. Stability can be improved.

It has also been surprisingly found that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether in combination with an alkaline earth metal peroxide ignition aid can advantageously significantly improve the combustion properties of the combustible heat source according to the invention. turned out

In particular, surprisingly, it was found that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether in combination with an alkaline earth metal peroxide ignition aid can advantageously significantly improve the ignition propagation rate of the combustible heat source according to the invention. it turned out

Without being bound by theory, it is believed that a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether provides energy during ignition of a combustible heat source according to the present invention. Without being bound by theory, it is believed that this improves the rate of propagation of ignition of combustible heat sources according to the present invention.

It has also surprisingly been found that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether can advantageously significantly improve the mechanical properties of the combustible heat source according to the invention.

Without wishing to be bound by theory, it is believed that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether modifies the agglomeration of the carbon and alkaline earth metal peroxide ignition aids during formation of a combustible heat source according to the present invention. . Without being bound by theory, it is believed that this affects the mechanical properties of the combustible heat source according to the present invention.

As used herein in connection with the present invention, the terms “distal”, “upstream” and “anterior” and the terms “proximal”, “downstream” and “posterior” refer to a component of an aerosol-generating article according to the present invention, or Used to describe the relative element of a part of a component. An aerosol-generating article according to the present invention comprises a proximal end through which, in use, the aerosol exits the aerosol-generating article for delivery to a user. The proximal end of the aerosol-generating article may also be referred to as the mouth end of the aerosol-generating article. In use, the user draws on the proximal end of the aerosol-generating article to inhale the aerosol generated by the aerosol-generating article.

An aerosol-generating article according to the invention comprises a distal end. The combustible heat source is located at or proximate to the distal end of the aerosol-generating article. The mouth end of the aerosol-generating article is downstream of the distal end of the aerosol-generating article. The proximal end of the aerosol-generating article may also refer to the downstream end of the aerosol-generating article, and the distal end of the aerosol-generating article may also refer to the upstream end of the aerosol-generating article. A component or portion of a component of an aerosol-generating article according to the present invention may be described as being upstream or downstream of each other based on their relative position between the proximal end of the aerosol-generating article and the distal end of the aerosol-generating article.

A combustible heat source according to the present invention has a front end face and a rear end face. The front end face 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 aerosol-generating article. The rear end face of the combustible heat source is at the downstream end of the combustible heat source. The downstream end of the combustible carbonaceous heat source is the end of the combustible heat source closest to the proximal end of the aerosol-generating article.

As used herein in connection with the present invention, the term "longitudinal direction" is used to describe the direction between the upstream and downstream ends of a combustible heat source according to the present invention and an aerosol-generating article according to the present invention.

As used herein in connection with the present invention, the term “transverse” is used to describe a direction perpendicular to the longitudinal direction. That is, the direction is perpendicular to the direction between the upstream and downstream ends of the combustible heat source according to the invention and the aerosol-generating article according to the invention.

As used herein in connection with the present invention, the term "length" is used to describe the maximum dimension in the longitudinal direction of the combustible heat source according to the present invention and an aerosol-generating article according to the present invention.

As used herein in connection with the present invention, the term “diameter” is used to describe the maximum dimension in the transverse direction of the combustible heat source according to the present invention and the aerosol-generating article according to the present invention.

The combustible heat source according to the present invention is a carbonaceous heat source.

As used herein in connection with the present invention, the term "carbonaceous" is used to describe a combustible heat source comprising carbon.

The combustible heat source according to the present invention comprises carbon as fuel.

The combustible heat source may comprise at least about 25 weight percent carbon.

Unless otherwise stated, the weight percentages of the components of the combustible heat source recited herein are based on the total dry weight of the combustible heat source.

Preferably, the combustible heat source comprises at least about 30 weight percent carbon.

More preferably, the combustible heat source comprises at least about 35 weight percent carbon.

The combustible heat source may comprise at least about 40 weight percent carbon.

The combustible heat source may comprise up to about 60 weight percent carbon.

Preferably, the combustible heat source comprises no more than about 55 weight percent carbon.

More preferably, the combustible heat source comprises up to about 50 weight percent carbon.

The combustible heat source may comprise up to about 45 weight percent carbon.

The combustible heat source comprises from about 25% to about 60% carbon by weight, from about 25% to about 55% carbon by weight, from about 25% to about 50% carbon by weight or from about 25% to about 45% carbon by weight. may include.

Preferably, the combustible heat source is from about 30 wt% to about 60 wt% carbon, from about 30 wt% to about 55 wt% carbon, from about 30 wt% to about 50 wt% carbon or from about 30 wt% to about 45 wt% carbon. % carbon by weight.

More preferably, the combustible heat source is from about 35 wt% to about 60 wt% carbon, from about 35 wt% to about 55 wt% carbon, from about 35 wt% to about 50 wt% carbon or from about 35 wt% to about 35 wt% carbon. 45% by weight of carbon.

The combustible heat source may be from about 40% to about 60% carbon by weight, from about 40% to about 55% carbon by weight, from about 40% to about 50% carbon by weight or from about 40% to about 45% carbon by weight. may include.

A combustible heat source according to the present invention may be formed using one or more suitable carbon materials. Advantageously, the combustible heat source according to the invention comprises at least one carbonized material. Suitable carbon materials are well known in the art and include, but are not limited to, carbon powder and charcoal powder.

The combustible heat source according to the present invention comprises an alkaline earth metal peroxide ignition aid.

As used herein in connection with the present invention, the term "alkaline earth metal peroxide ignition aid" is used to describe an alkaline earth metal peroxide that releases one or both of energy and oxygen during ignition of a combustible heat source, wherein the alkaline earth metal The rate of release of one or both of energy and oxygen by the peroxide is not limited to ambient oxygen diffusion. In other words, the rate of release of one or both of energy and oxygen by the alkaline earth metal peroxide during ignition of a combustible heat source is largely independent of the rate at which ambient oxygen can reach the alkaline earth metal peroxide.

The amount of one or both of the energy and oxygen released by the alkaline earth metal peroxide ignition aid during ignition of the combustible heat source may be sufficient to cause the combustible heat source to undergo a two stage combustion process.

In an initial first stage, the combustible heat source according to the present invention may exhibit a 'boost' in temperature, and in a subsequent second stage, the combustible heat source according to the present invention may undergo sustained combustion at a lower 'cruising' temperature.

The initial 'boost' in the temperature of the combustible heat source according to the present invention may occur due to the very rapid propagation of heat throughout the combustible heat source upon ignition of a portion of the combustible heat source. The very rapid propagation of heat may be the result of a chain reaction in which a portion of the combustible heat source that is ignited triggers the ignition of an adjacent unignited portion of the combustible heat source.

In use, in an aerosol-generating article according to the invention, a rapid increase in the temperature of the combustible heat source according to the invention to a 'boost' temperature can rapidly raise the temperature of the aerosol-forming substrate to the level at which the volatile compound is released from the aerosol-forming substrate. have. This can ensure that the aerosol-generating article according to the invention generates an aerosol that is sensorily acceptable during the initial puff. Subsequent reduction of the temperature of the combustible heat source according to the invention to the 'cruising' temperature can ensure that the temperature of the aerosol-forming substrate does not reach a level at which combustion or thermal degradation of the aerosol-forming substrate occurs.

Controlling the temperature of the combustible heat source according to the invention in the manner described above advantageously produces a sensory acceptable aerosol during the initial puff, as well as in the present invention, in which combustion or thermal degradation of the aerosol-forming substrate is substantially avoided. according to the aerosol-generating article may be provided.

The amount of alkaline earth metal peroxide ignition aid that must be included to achieve the two-step process described above will vary depending on the specific alkaline earth metal peroxide ignition aid included in the combustible heat source.

In general, the greater the amount of one or both of energy and oxygen released by the alkaline earth metal peroxide ignition aid per unit mass, the higher the amount of alkaline earth metal peroxide ignition aid that must be included in the combustible heat source to achieve the two-stage combustion process described above. quantity is lowered.

The combustible heat source may include at least about 15 weight percent alkaline earth metal peroxide ignition aid.

Preferably, the combustible heat source comprises at least about 20 weight percent alkaline earth metal peroxide ignition aid.

More preferably, the combustible heat source comprises at least about 30 weight percent alkaline earth metal peroxide ignition aid.

The combustible heat source may comprise at least about 40 weight percent alkaline earth metal peroxide ignition aid.

The combustible heat source may comprise up to about 65 weight percent alkaline earth metal peroxide ignition aid.

Preferably, the combustible heat source comprises up to about 60% by weight alkaline earth metal peroxide ignition aid.

More preferably, the combustible heat source comprises up to about 55% by weight of an alkaline earth metal peroxide ignition aid.

The combustible heat source may comprise up to about 50 weight percent alkaline earth metal peroxide ignition aid.

The combustible heat source comprises from about 15 wt% to about 65 wt% alkaline earth metal peroxide ignition aid, from about 15 wt% to about 60 wt% alkaline earth metal peroxide ignition aid, from about 15 wt% to about 55 wt% alkaline earth metal peroxide ignition aid or from about 15% to about 50% by weight of an alkaline earth metal peroxide ignition aid.

Preferably, the combustible heat source comprises from about 20 wt% to about 65 wt% alkaline earth metal peroxide ignition aid, from about 20 wt% to about 60 wt% alkaline earth metal peroxide ignition aid, from about 20 wt% to about 55 wt% alkali an earth metal peroxide ignition aid or from about 20% to about 50% by weight of an alkaline earth metal peroxide ignition aid.

More preferably, the combustible heat source comprises from about 30% to about 65% by weight of an alkaline earth metal peroxide ignition aid, from about 30% to about 60% by weight of an alkaline earth metal peroxide ignition aid, from about 30% to about 55% by weight an alkaline earth metal peroxide ignition aid or from about 30% to about 50% by weight alkaline earth metal peroxide ignition aid.

The combustible heat source comprises from about 40 wt% to about 65 wt% alkaline earth metal peroxide ignition aid, from about 40 wt% to about 60 wt% alkaline earth metal peroxide ignition aid, from about 40 wt% to about 55 wt% alkaline earth metal peroxide ignition aid or from about 40% to about 50% by weight of an alkaline earth metal peroxide ignition aid.

Preferably, the alkaline earth metal peroxide ignition aid is calcium peroxide.

The combustible heat source may comprise at least about 15 weight percent calcium peroxide.

Preferably, the combustible heat source comprises at least about 20 weight percent calcium peroxide.

More preferably, the combustible heat source comprises at least about 30 weight percent calcium peroxide.

The combustible heat source may comprise at least about 40 weight percent calcium peroxide.

The combustible heat source may comprise up to about 65 weight percent calcium peroxide.

Preferably, the combustible heat source comprises up to about 60 weight percent calcium peroxide.

More preferably, the combustible heat source comprises up to about 55 weight percent calcium peroxide.

The combustible heat source may comprise up to about 50 weight percent calcium peroxide.

The combustible heat source may be from about 15 wt% to about 65 wt% calcium peroxide, from about 15 wt% to about 60 wt% calcium peroxide, from about 15 wt% to about 55 wt% calcium peroxide or from about 15 wt% to about 50 wt% % calcium peroxide.

Preferably, the combustible heat source is from about 20 wt% to about 65 wt% calcium peroxide, from about 20 wt% to about 60 wt% calcium peroxide, from about 20 wt% to about 55 wt% calcium peroxide or from about 20 wt% to about 50% by weight calcium peroxide.

More preferably, the combustible heat source is from about 30 wt% to about 65 wt% calcium peroxide, from about 30 wt% to about 60 wt% calcium peroxide, from about 30 wt% to about 55 wt% calcium peroxide or about 30 wt% % to about 50% by weight calcium peroxide.

The combustible heat source comprises from about 40% to about 65% by weight calcium peroxide, from about 40% to about 60% by weight calcium peroxide, from about 40% to about 55% by weight calcium peroxide, or from about 40% to about 50% by weight. % calcium peroxide.

The combustible heat source according to the invention is a solid combustible heat source.

Preferably, the combustible heat source is a monolithic solid combustible heat source. That is, it is an integral solid combustible heat source.

A combustible heat source according to the invention comprises a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose.

As used herein in connection with the present invention, the term "binder" is used to describe a component of a combustible heat source capable of binding together the carbon and alkaline earth metal peroxide ignition aid and any other components of the combustible heat source. .

As used herein in connection with the present invention, the term “additional cellulose ether” is used to describe a cellulose ether other than carboxymethyl cellulose.

The combustible heat source may include at least about 3 weight percent binder.

Preferably, the combustible heat source comprises at least about 4 weight percent binder.

More preferably, the combustible heat source comprises at least about 5 weight percent binder.

The combustible heat source may comprise up to about 20 weight percent binder.

Preferably, the combustible heat source comprises up to about 15% by weight binder.

More preferably, the combustible heat source comprises up to about 10 weight percent binder.

The combustible heat source may comprise from about 3 wt% to about 20 wt% binder, from about 3 wt% to about 15 wt% binder, or from about 3 wt% to about 10 wt% binder.

Preferably, the combustible heat source comprises from about 4 weight percent to about 20 weight percent binder, from about 4 weight percent to about 15 weight percent binder, or from about 4 weight percent to about 10 weight percent binder.

More preferably, the combustible heat source comprises from about 5 weight percent to about 20 weight percent binder, from about 5 weight percent to about 15 weight percent binder, or from about 5 weight percent to about 10 weight percent binder.

The binder includes carboxymethyl cellulose.

The combustible heat source may comprise at least about 1.5 weight percent carboxymethyl cellulose.

Preferably, the combustible heat source comprises at least about 2 weight percent carboxymethyl cellulose.

More preferably, the combustible heat source comprises at least about 3 weight percent carboxymethyl cellulose.

The combustible heat source may comprise up to about 15 weight percent carboxymethyl cellulose.

Preferably, the combustible heat source comprises up to about 12 weight percent carboxymethyl cellulose.

More preferably, the combustible heat source comprises up to about 8% by weight of carboxymethyl cellulose.

The combustible heat source may comprise from about 1.5 wt% to about 15 wt% carboxymethyl cellulose, from about 1.5 wt% to about 12 wt% carboxymethyl cellulose or from about 1.5 wt% to about 8 wt% carboxymethyl cellulose.

Preferably, the combustible heat source comprises from about 2% to about 15% by weight of carboxymethyl cellulose, from about 2% to about 12% by weight of carboxymethyl cellulose, or from about 2% to about 8% by weight of carboxymethyl cellulose. include

More preferably, the combustible heat source is from about 3 wt% to about 15 wt% carboxymethyl cellulose, from about 3 wt% to about 12 wt% carboxymethyl cellulose, or from about 3 wt% to about 8 wt% carboxymethyl cellulose includes

The binder comprises at least one additional cellulose ether.

The combustible heat source may comprise at least about 0.2 weight percent of at least one additional cellulose ether.

The combustible heat source may comprise at least about 0.5 weight percent of at least one additional cellulose ether.

Preferably, the combustible heat source comprises at least about 0.75 weight percent of the at least one additional cellulose ether.

More preferably, the combustible heat source comprises at least about 1% by weight of the at least one additional cellulose ether.

The combustible heat source may comprise up to about 6 weight percent of at least one additional cellulose ether.

Preferably, the combustible heat source comprises up to about 5% by weight of at least one additional cellulose ether.

More preferably, the combustible heat source comprises up to about 4% by weight of at least one additional cellulose ether.

The combustible heat source may comprise up to about 3 weight percent of at least one additional cellulose ether.

The combustible heat source comprises from about 0.2% to about 6% by weight of at least one additional cellulose ether, from about 0.2% to about 5% by weight of at least one additional cellulose ether, from about 0.5% to about 4% by weight of the at least one additional cellulose ethers, or from about 0.5% to about 3% by weight of at least one additional cellulose ether.

The combustible heat source comprises from about 0.5% to about 6% by weight of at least one additional cellulose ether, from about 0.5% to about 5% by weight of at least one additional cellulose ether, from about 0.5% to about 4% by weight of at least one additional cellulose ethers, or from about 0.5% to about 3% by weight of at least one additional cellulose ether.

Preferably, the combustible heat source comprises from about 0.75% to about 6% by weight of at least one additional cellulose ether, from about 0.75% to about 5% by weight of at least one additional cellulose ether, from about 0.75% to about 4% by weight. of at least one additional cellulose ether, or from about 0.75% to about 3% by weight of at least one additional cellulose ether.

More preferably, the combustible heat source comprises from about 1% to about 6% by weight of at least one additional cellulose ether, from about 1% to about 5% by weight of at least one additional cellulose ether, from about 1% to about 4% by weight. % of at least one additional cellulose ether, or from about 1% to about 3% by weight of at least one additional cellulose ether.

The binder comprises a combination of carboxymethyl cellulose and at least one additional cellulose ether.

Preferably, the binder comprises a combination of carboxymethyl cellulose and at least one additional cellulose ether selected from the group consisting of ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose.

The ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source may be at least about 1:1.

Preferably, the ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source is at least about 3:2.

More preferably, the ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source may be at least about 2:1.

The ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source may be about 4:1 or less.

Preferably, the ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source may be about 7:2 or less.

More preferably, the ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source may be about 3:1 or less.

The ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source may be about 5:2 or less.

The ratio of weight percent of carboxymethyl cellulose to weight percent of at least one additional cellulose ether in the combustible heat source is from about 1:1 to about 4:1, from about 1:1 to about 7:2, from about 1:1 to about 3 :1 or from about 1:1 to about 5:2.

Preferably, the ratio of weight percent of carboxymethyl cellulose to weight percent of at least one additional cellulose ether in the combustible heat source is from about 3:2 to about 4:1, from about 3:2 to about 7:2, about 3: 2 to about 3:1 or about 3:2 to about 5:2.

More preferably, the ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source is from about 2:1 to about 4:1, from about 2:1 to about 7:2, about 2 :1 to about 3:1 or about 2:1 to about 5:2.

The binder may include a non-flammable inorganic sheet silicate binder.

As used herein in connection with the present invention, the term “non-combustible” is used to describe a component that does not burn or decompose at the temperature reached during ignition and combustion of a combustible heat source.

As used herein in the context of the present invention, the term "non-combustible inorganic sheet silicate binder" means that during ignition and combustion of a combustible heat source, the binder is stable at the temperature at which it is treated, and is capable of remaining substantially intact during and after combustion of the combustible heat source. Used to describe inorganic sheet silicate binders.

Suitable non-combustible inorganic sheet silicate binders include clays such as bentonite, montmorillonite, and kaolinite; mica; and serpentinite.

As used herein in the context of the present invention, the term “clay” is used to describe an aluminum phyllosilicate material formed from two-dimensional sheets of silicate and aluminate ions that form distinct layered structures within the clay.

Advantageously, the binder may not comprise a non-combustible inorganic sheet silicate binder.

The combustible heat source according to the invention may comprise one or more carboxylate combustion salts.

As used herein in connection with the present invention, the term “carboxylate combustion salt” is used to describe salts of carboxylic acids other than carbonic acid. That is, as used herein in connection with the present invention, the term “carboxylate combustion salt” does not include carbonates or bicarbonates.

The one or more carboxylate combustion salts may advantageously promote combustion of the combustible heat source.

Carboxylate combustion salts may comprise monovalent, divalent, or trivalent cations and carboxylate anions.

Carboxylate combustion salts may include monovalent, divalent, or trivalent cations and acetate, citrate or succinate anions.

The carboxylate combustion salt may be an alkali metal carboxylate combustion salt. For example, the carboxylate combustion salt can be a sodium carboxylate combustion salt or a potassium carboxylate combustion salt.

The carboxylate combustion salt may be an alkali metal acetate, an alkali metal citrate or an alkali metal succinate.

Most preferably, the carboxylate combustion salt is potassium citrate.

The combustible heat source may comprise a single carboxylate combustion salt.

The combustible heat source may comprise a combination of two or more different carboxylate combustion salts. The two or more different carboxylate combustion salts may comprise different carboxylate anions. The two or more different carboxylate combustion salts may comprise different cations. For example, the combustible heat source may include a combination of alkali metal citrate and alkaline earth metal succinate.

The combustible heat source may comprise at least about 0.1 weight percent of one or more carboxylate combustion salts.

The combustible heat source may comprise at least about 0.5 weight percent of one or more carboxylate combustion salts.

Preferably, the combustible heat source comprises at least about 1 weight percent of one or more carboxylate combustion salts.

The combustible heat source may comprise up to about 4% by weight of one or more carboxylate combustion salts.

Preferably, the combustible heat source comprises up to about 3% by weight of one or more carboxylate combustion salts.

The combustible heat source may comprise from about 0.1% to about 4% by weight of one or more carboxylate combustion salts or from about 0.1% to about 3% by weight of one or more carboxylate combustion salts.

The combustible heat source may comprise from about 0.5% to about 4% by weight of one or more carboxylate combustion salts or from about 0.5% to about 3% by weight of one or more carboxylate combustion salts.

Preferably, the combustible heat source comprises from about 1% to about 4% by weight of one or more carboxylate combustion salts or from about 1% to about 3% by weight of one or more carboxylate combustion salts.

Preferably, the combustible heat source according to the present invention is substantially uniform in composition.

The combustible heat source according to the present invention may have any desired length.

A combustible heat source according to the present invention may have a length of about 5 mm to about 20 mm.

Preferably, the combustible heat source according to the present invention has a length of from about 7 mm to about 17 mm.

More preferably, the combustible heat source according to the present invention has a length of from about 7 mm to about 15 mm.

Most preferably, the combustible heat source according to the present invention has a length of about 7 mm to about 13 mm.

The combustible heat source according to the present invention may have any desired diameter.

A combustible heat source according to the present invention may have a diameter of from about 5 mm to about 15 mm.

Preferably, the combustible heat source according to the present invention has a diameter of about 5 mm to about 10 mm.

More preferably, the combustible heat source according to the present invention has a diameter of about 7 mm to about 8 mm.

The combustible heat source according to the present invention may be tapered such that the diameter of the rear portion of the combustible heat source is greater than the diameter of the front portion of the combustible heat source.

Preferably, the combustible heat source according to the invention is of substantially constant diameter.

Preferably, the combustible heat source according to the invention has a substantially circular cross-section.

Preferably, the combustible heat source according to the invention is substantially cylindrical.

A combustible heat source according to the present invention may have a mass of about 300 mg to about 500 mg. For example, a combustible heat source according to the present invention has a mass of about 400 mg to about 450 mg.

A combustible heat source according to the present invention may have an apparent density of from about 0.6 g/cm3 to about 1.0 g/cm3.

A combustible heat source according to the present invention may have a porosity of from about 20% to about 80% as measured by, for example, mercury porosimetry or helium pycnometry.

For example, a combustible heat source according to the present invention may contain, for example, from about 20% to 60%, from about 50% to about 70%, or from about 50% to about 60%, as measured by mercury porosimetry or helium gravimetry. may have a porosity of

The desired porosity can be readily achieved during the manufacture of the combustible heat source according to the present invention using conventional methods and techniques.

A combustible heat source according to the present invention comprises: combining one or more carbon materials of the combustible heat source, an alkaline earth metal peroxide ignition aid, a binder and any other components to form a mixture; It can be formed by forming the mixture into a desired shape.

Preferably, the combustible heat source according to the present invention comprises: combining one or more carbon materials of the combustible heat source, an alkaline earth metal peroxide ignition aid, a binder and any other components to form a granular mixture; It is formed by forming the granule mixture into the desired shape.

Advantageously, the binder is dispersed in intergranular and intragranular locations within the granule mixture.

One or more carbon materials, alkaline earth metal peroxide ignition aids, binders and any other components of the combustible heat source use suitable known methods such as, for example, dry granulation, wet granulation, high shear mixing, spheronization or extrusion. can be combined to form a mixture.

Preferably, at least one carbon material of the combustible heat source, an alkaline earth metal peroxide ignition aid, a binder and any other components are combined to form a granule mixture by wet granulation.

The mixture may be formed into a desired shape using any suitable known ceramic forming method, such as, for example, slip casting, extrusion, injection molding, mold compression or pressing.

Preferably, the mixture is formed into the desired shape by pressing.

Preferably, after formation the desired shape is dried to reduce its moisture content. The desired shape can be dried using any suitable known method. For example, the desired shape may be dried in an oven at a temperature of about 85°C to about 105°C.

The combustible heat source may be an unblind combustible heat source.

As used herein in the context of the present invention, the term "unblind" describes a combustible heat source comprising at least one airflow channel extending along the length of the combustible heat source and through which air may be drawn in for inhalation by a user. used to do

Where the combustible heat source is an unblind combustible heat source, a non-combustible substantially air impermeable barrier may be provided between the non-blind combustible heat source and the at least one airflow channel.

As used herein in connection with the present invention, the term “non-combustible barrier” is used to describe a barrier that is substantially non-combustible at the temperatures reached by the combustible heat source during ignition and combustion of the combustible heat source.

The inclusion of a non-combustible substantially air impermeable barrier between the unblind combustible heat source and the at least one airflow channel, advantageously in use, allows combustion and decomposition products formed during ignition and combustion of the unblind combustible heat source to close the at least one airflow channel. It can substantially prevent or inhibit entry of the drawn air through.

In use, the inclusion of a non-combustible substantially air impermeable barrier between the unblind combustible heat source and the at least one airflow channel may advantageously substantially prevent or inhibit activation of combustion of the non-blind combustible heat source during a puff by a user. have. When used in an aerosol-generating article according to the present invention, it can advantageously substantially prevent or inhibit a surge in the temperature of the aerosol-forming substrate of the aerosol-generating article during puffs by the user.

The barrier between the unblind combustible heat source and the at least one airflow channel may have a low thermal conductivity or a high thermal conductivity.

The thickness of the barrier between the unblind combustible heat source and the at least one airflow channel may be selected to achieve good performance.

The barrier between the unblind combustible heat source and the at least one airflow channel may be formed of one or more suitable materials that are substantially thermally stable and non-combustible at the temperatures achieved thereby during ignition and combustion of the unblind combustible heat source. Suitable materials are known in the art and include clay; metal oxides such as iron oxide, alumina, titania, silica, silica-alumina, zirconia and ceria; zeolite; zirconium phosphate and other ceramic materials; and combinations thereof.

A barrier between the unblind combustible heat source and the at least one airflow channel may be attached or otherwise secured to an inner surface of the at least one airflow channel of the unblind combustible heat source.

Suitable methods for attaching or securing a barrier to the interior surface of at least one airflow channel of an unblind combustible heat source are known in the art and include, but are not limited to, those described in US 5,040,551 and WO 2009/074870 A2.

The barrier between the unblind combustible heat source and the at least one airflow channel may include a liner inserted into the at least one airflow channel.

Preferably, the combustible heat source is a blind combustible heat source.

As used herein in connection with the present invention, the term “blind” refers to a combustible heat source that extends along the length of the combustible heat source and does not include any airflow channels through which air may be drawn in for inhalation by a user. used to describe

A blind combustible heat source according to the present invention and an unblind combustible heat source according to the present invention may comprise one or more closed or blocked channels through which air may not be drawn in for inhalation by a user.

For example, the combustible heat source may include one or more closed passageways extending only partially along the length of the combustible heat source.

Inclusion of one or more closed channels may increase the surface area of the combustible heat source exposed to oxygen from the air. This can advantageously facilitate ignition and continuous combustion of the combustible heat source.

An aerosol-generating article according to the invention comprises a combustible heat source according to the invention and an aerosol-forming substrate.

As used herein in the context of the present invention, the term “aerosol-forming substrate” is used to describe a substrate comprising an aerosol-forming material capable of releasing a volatile compound upon heating that is capable of forming an aerosol. Aerosols emanating from the aerosol-forming substrate of an aerosol-generating article according to the present invention may be visible or invisible, and may include vapors (e.g., particulates of substances in the gaseous state, usually liquids or solids at room temperature) as well as gases and It may contain droplets of condensed vapor.

The aerosol-forming substrate may be in the form of a plug or segment comprising a material capable of releasing upon heating a volatile compound capable of forming an aerosol surrounded by a wrapper. When the aerosol-forming substrate is in the form of a plug or segment, the entire plug or segment including the wrapper is considered to be the aerosol-forming substrate.

The aerosol-forming substrate is downstream of the combustible heat source. That is, the aerosol-forming substrate is between the combustible heat source and the distal end of the aerosol-generating article.

The aerosol-forming substrate may abut a combustible heat source.

The aerosol-forming substrate may be longitudinally spaced from the combustible heat source.

Advantageously, the aerosol-forming substrate comprises an aerosol-forming material comprising an aerosol former.

The aerosol former may be any suitable compound or mixture of compounds that, in use, facilitates the formation of a dense and stable aerosol and is substantially resistant to thermal degradation at the operating temperature of the aerosol-generating article. Suitable aerosol formers are known in the art and include polyhydric alcohols such as triethylene glycol, propylene glycol, 1,3-butanediol and glycerin; esters of polyhydric alcohols such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di-, or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate.

Advantageously, the aerosol former comprises at least one polyhydric alcohol.

More advantageously, the aerosol former comprises glycerin.

Preferably, the aerosol-forming substrate is a solid aerosol-forming substrate. The aerosol-forming substrate may include both solid and liquid components.

The aerosol-forming substrate may comprise a plant-based material. The aerosol-forming substrate may comprise a homogenized plant-based material.

The aerosol-forming substrate may comprise nicotine.

The aerosol-forming substrate may comprise tobacco material.

As used herein in connection with the present invention, the term “tobacco material” includes tobacco leaves, tobacco ribs, tobacco stems, tobacco stalks, tobacco powder, puffed tobacco, reconstituted tobacco material and homogenized tobacco material. However, it is used to describe any material, including but not limited to tobacco.

Tobacco material may be in the form of, for example, powder, granules, pellets, shreds, strands, strips, sheets, or any combination thereof.

Advantageously, the aerosol-forming substrate comprises a sheet of homogenised tobacco material.

As used herein in connection with the present invention, the term “homogenized tobacco material” is used to describe a material formed by agglomerating particulate tobacco.

In certain embodiments, the aerosol-forming substrate advantageously comprises a plurality of strands of homogenised tobacco material.

Advantageously, the plurality of strands of homogenised tobacco material may be aligned substantially parallel to one another within the aerosol-forming substrate.

In certain embodiments, the aerosol-forming substrate advantageously comprises a corrugated sheet of homogenised tobacco material.

The aerosol-forming substrate may comprise a rod comprising a corrugated sheet of homogenised tobacco material.

As used herein in connection with the present invention, the term “rod” is used to describe a substantially cylindrical element of a substantially circular, oval, or elliptical cross-section.

As used herein in connection with the present invention, the term “sheet” is used to describe a laminate element having a width and length substantially greater than its thickness.

As used herein in the context of the present invention, the term "corrugated" is used to describe a sheet that is entangled, folded, or otherwise compressed or retracted substantially transverse to the longitudinal axis of the aerosol-generating article. .

The aerosol-forming substrate may include an aerosol-forming material and a wrapper around the aerosol-forming material.

The wrapper may be formed of any suitable sheet material capable of enclosing the aerosol-forming material to form an aerosol-forming substrate.

In certain embodiments, the aerosol-forming substrate may comprise a rod comprising a corrugated sheet of homogenised tobacco material and a wrapper around and in contact with the tobacco material.

In certain embodiments, the aerosol-forming substrate advantageously comprises a corrugated texturized sheet of homogenised tobacco material.

As used herein in connection with the present invention, the term "textured sheet" is used to describe a sheet that has been crimped, embossed, engraved, perforated or otherwise deformed.

Using a texturized sheet of homogenized tobacco material may advantageously facilitate pleating of the homogenized sheet of tobacco material to form an aerosol-forming substrate.

The aerosol-forming substrate may comprise a gathered texturized sheet of homogenised tobacco material comprising a plurality of spaced apart indentations, projections, perforations, or any combination thereof.

The aerosol-forming substrate may comprise a corrugated crimped sheet of homogenized tobacco material.

As used herein in connection with the present invention, the term "crimped sheet" is used to describe a sheet having a plurality of substantially parallel ridges or corrugations.

Advantageously, when an aerosol-generating article according to the invention comprising an aerosol-forming substrate is assembled, the substantially parallel ridges or corrugations extend along or parallel to the longitudinal axis of the aerosol-generating article. This facilitates pleating of the crimped sheet of homogenised tobacco material to form an aerosol-forming substrate.

However, the crimped sheet of homogenised tobacco material for inclusion in the aerosol-forming substrate of an aerosol-generating article according to the present invention may alternatively or additionally be at an acute angle or with respect to the longitudinal axis of the aerosol-generating article when the aerosol-generating article is assembled. It will be appreciated that it may have a plurality of substantially parallel ridges or corrugations disposed at an obtuse angle.

Preferably, the aerosol-forming substrate is substantially cylindrical.

The aerosol-forming substrate may have a length of from about 5 mm to about 20 mm.

Preferably, the aerosol-forming substrate has a length of from about 6 mm to about 15 mm.

More preferably, the aerosol-forming substrate has a length of from about 7 mm to about 12 mm.

The aerosol-forming substrate may have a diameter of from about 5 mm to about 15 mm.

Preferably, the aerosol-forming substrate has a length of from about 5 mm to about 10 mm.

More preferably, the aerosol-forming substrate has a length of from about 7 mm to about 8 mm.

An aerosol-generating article according to the present invention may comprise a combustible heat source according to the present invention, an aerosol-forming substrate downstream of the combustible heat source and one or more other components.

The combustible heat source of the aerosol-generating article, the aerosol-forming substrate, and, if included, one or more other components may be assembled within one or more wrappers to form an elongate rod having a proximal end and an opposed distal end. Thus, an aerosol-generating article according to the present invention may resemble a conventional lit end cigarette.

The one or more other components may include one or more of a cap, a transfer element or spacer element, an aerosol cooling element or heat exchanger and a mouthpiece.

An aerosol-generating article according to the present invention may comprise a cap configured to at least partially cover a front portion of the combustible heat source. The cap may be removable to expose the front portion of the combustible heat source prior to use of the aerosol-generating article. The cap may advantageously protect the combustible heat source prior to use of the aerosol-generating article.

As used herein in connection with the present invention, the term “cap” is used to describe a protective cover at the distal end of an aerosol-generating article that substantially surrounds the front portion of the combustible heat source.

For example, an aerosol-generating article according to the present invention may comprise a removable cap attached at a line of weakness to the distal end of the aerosol-generating article, the cap as described in WO 2014/086998 A1. It includes a cylindrical plug of material surrounded by a wrapper.

An aerosol-generating article according to the present invention may comprise a delivery element, or a spacer element, downstream of the aerosol-forming substrate. That is, the delivery element or spacer element is positioned between the aerosol-forming substrate and the proximal end of the aerosol-generating article.

The delivery element may abut the aerosol-forming substrate. Alternatively, the delivery element may be longitudinally spaced from the aerosol-forming substrate.

The inclusion of a transfer element may advantageously allow cooling of the aerosol generated by heat transfer from the combustible heat source to the aerosol-forming substrate.

The inclusion of a delivery element advantageously allows the overall length of the aerosol-generating article to be adjusted to a desired value through appropriate selection of the length of the delivery element. For example, the inclusion of a delivery element allows the overall length of the aerosol-generating article to be adjusted to a length similar to that of a conventional cigarette.

The transfer element may have a length of from about 7 mm to about 50 mm. For example, the transmission element may have a length of about 10 mm to about 45 mm or a length of about 15 mm to about 30 mm.

The delivery element may have a different length depending on the desired overall length of the aerosol-generating article and the presence and length of other components within the aerosol-generating article.

The transmission element may comprise an open end tubular hollow body. In use, air drawn into the aerosol-generating article by the user may pass through the open end tubular hollow body as it passes downstream through the aerosol-generating article from the aerosol-forming substrate to the proximal end of the aerosol-generating article.

The open-ended tubular hollow body may be formed of one or more materials that are substantially thermally stable at the temperature of the aerosol generated by heat transfer from the combustible heat source to the aerosol-forming substrate. Suitable materials are known in the art and include paper, cardboard; thermoplastic resins, such as cellulose acetate; and ceramics.

Aerosol-generating articles according to the invention may comprise an aerosol cooling element or heat exchanger downstream of the aerosol-forming substrate. That is, it is located between the aerosol cooling element or heat exchanger aerosol-forming substrate and the proximal end of the aerosol-generating article.

The aerosol cooling element may advantageously cool an aerosol generated by heat transfer from the combustible heat source to the aerosol-forming substrate.

The aerosol cooling element may comprise a plurality of longitudinally extending channels.

The aerosol cooling element may comprise a corrugated sheet material consisting of a material selected from the group consisting of metallic foil, polymeric material, and substantially non-porous paper or cardboard.

The aerosol cooling element is a material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose acetate (CA), and aluminum foil. may include a corrugated sheet of

The aerosol cooling element may comprise a corrugated sheet of a biodegradable polymer material such as polylactic acid (PLA) or a Mater-Bi ^® grade (a group of commercially available starch-based copolyesters).

If the aerosol-generating article according to the invention comprises a delivery element downstream of the aerosol-forming substrate and an aerosol cooling element downstream of the aerosol-forming substrate, the aerosol-cooling element is preferably downstream of the delivery element. That is, the aerosol cooling element is preferably located between the delivery element and the proximal end of the aerosol-generating article.

The aerosol-generating article according to the invention may comprise a mouthpiece downstream of the aerosol-forming substrate. That is, the mouthpiece is positioned between the aerosol-forming article and the proximal end of the aerosol-generating article.

Preferably, the aerosol-generating article according to the invention comprises a mouthpiece located at the proximal end of the aerosol-generating article.

The mouthpiece may have low or very low filtration efficiency.

The mouthpiece may be a single segment mouthpiece.

The mouthpiece may be a multi-segment mouthpiece.

The mouthpiece may include one or more segments comprising filtration material.

Suitable filtration materials are known in the art and include, but are not limited to, cellulose acetate and paper.

The mouthpiece may include one or more segments comprising an absorbent material.

The mouthpiece may include one or more segments comprising an adsorbent material.

Suitable absorbent materials and suitable absorbent materials are known in the art and include, but are not limited to, activated carbon, silica gel, and zeolites.

Aerosol-generating articles according to the present invention may comprise one or more aerosol modifiers downstream of the aerosol-forming substrate. For example, when included, one or more of the mouthpiece, delivery element and aerosol cooling element of an aerosol-generating article according to the present invention may comprise one or more aerosol modifiers.

As used herein in connection with the present invention, the term "aerosol modifier" is used to describe an agent that, in use, modifies one or more characteristics or properties of an aerosol generated by the aerosol-forming substrate of an aerosol-generating article.

Suitable aerosol modifiers include, but are not limited to, flavoring agents and chemesthetic agents.

As used herein in connection with the present invention, the term "object sensory agent", when used, refers to a user by means other than or in addition to perception through taste receptor cells or olfactory receptor cells. It is used to describe an agent that is perceived by the oral or olfactory senses. Perception of an object sensory is generally via a "trigeminal response" via the trigeminal nerve, glossopharyngeal nerve, vagus nerve, or some combination thereof. Typically, object sensitizers are perceived as hot, spicy, cold, or soothing sensations.

Aerosol-generating articles according to the invention may comprise one or more aerosol modifiers downstream of the aerosol-forming substrate which are both flavoring and object sensory agents. For example, when included, one or more of the mouthpiece, delivery element and aerosol cooling element of an aerosol-generating article according to the present invention may include menthol or other flavoring agent to provide a cooling object sensory effect.

Aerosol-generating articles according to the invention may comprise one or more heat-conducting elements.

Preferably, the aerosol-generating article according to the invention comprises a heat-conducting element around at least a portion of the aerosol-forming substrate. The heat-conducting element may advantageously transfer heat to the periphery of the aerosol-forming substrate by conduction.

More preferably, the aerosol-generating article according to the invention comprises a heat-conducting element around and in contact with at least a portion of the aerosol-forming substrate. This may advantageously facilitate conductive heat transfer to the periphery of the aerosol-forming substrate.

The heat-conducting element may surround the entire length of the aerosol-forming substrate. That is, the heat-conducting element may overlie the entire length of the aerosol-forming substrate.

Advantageously, the heat-conducting element is absent from the rear portion of the aerosol-forming substrate. That is, the aerosol-forming substrate advantageously extends longitudinally past the heat-conducting element in a downstream direction.

Preferably, the aerosol-forming substrate extends at least about 3 mm longitudinally past the heat-conducting element in a downstream direction.

Preferably, the aerosol-generating article according to the invention comprises a heat-conducting element around at least a portion of the combustible heat source and around at least a portion of the aerosol-forming substrate.

More preferably, the aerosol-generating article according to the invention comprises a heat-conducting element at least around the rear portion of the combustible heat source and at least around the front portion of the aerosol-forming substrate.

Most preferably, the aerosol-generating article according to the invention comprises a heat-conducting element around and in contact with at least the rear portion of the combustible heat source and at least around and in contact with the front portion of the aerosol-forming substrate.

The heat-conducting element may provide a thermal connection between the aerosol-forming substrate and the combustible heat source of the aerosol-generating article. This may advantageously facilitate suitable heat transfer from the combustible heat source to the aerosol-forming substrate, thereby helping to produce an acceptable aerosol.

Preferably, the rear portion of the heat source in contact with the heat-conducting element is between about 2 mm and about 8 mm in length.

More preferably, the rear portion of the heat source in contact with the heat-conducting element is from about 3 mm to about 5 mm long.

Preferably, the heat-conducting element is non-combustible.

The heat conducting element may be oxygen restrictive. In other words, the heat-conducting element may inhibit or resist passage of oxygen through the heat-conducting element.

The heat-conducting element may be formed of any suitable heat-conducting material or combination of materials.

Preferably, the heat-conducting element is about 10 W/(m K) per meter Kelvin, at 23° C. and 50% relative humidity, as measured using a modified transient plane source (MTPS) method. one having a bulk thermal conductivity of from about 500 W/(m·K) per meter Kelvin, more preferably from about 15 W/(m·K) per meter Kelvin to about 400 W/(m·K) per meter Kelvin The above thermally conductive material is included.

Advantageously, the heat-conducting element comprises one or more metals, one or more alloys, or a combination of one or more metals and one or more alloys.

Suitable thermally conductive materials are known in the art and include, for example, metal foils such as aluminum foil, iron foil and copper foil; and, for example, steel foils and alloy foils.

Advantageously, the heat-conducting element comprises an aluminum foil.

Aerosol-generating articles according to the present invention may comprise a non-combustible substantially air impermeable barrier between the rear end face of the combustible heat source and the aerosol-forming substrate.

By including a non-combustible substantially air impermeable barrier between the rear end face of the combustible heat source and the aerosol-forming substrate, it is possible to advantageously limit the temperature to which the aerosol-forming substrate is exposed during ignition and combustion of the combustible heat source. This may help to avoid or reduce combustion or thermal degradation of the aerosol-forming substrate during use of the aerosol-generating article.

By including a non-combustible, substantially air impermeable barrier between the rear end face of the combustible heat source and the aerosol-forming substrate, advantageously substantially prevents migration of constituents of the aerosol-forming substrate to the combustible heat source during storage and use of the aerosol-generating article. can be prevented or limited.

The barrier may abut one or both of the rear end face of the combustible heat source and the aerosol-forming substrate. Alternatively, the barrier may be longitudinally spaced from one or both of the aerosol-forming substrate and the rear end face of the combustible heat source.

Advantageously, the barrier is attached or otherwise secured to the rear end face of the combustible heat source.

Suitable methods for attaching or securing the barrier to the rear end face of the combustible heat source are known in the art: spray coating; vapor deposition; dipping; material transfer (eg, brushing or gluing); electrostatic deposition; pressing processing; or any combination thereof.

The barrier between the rear end face of the combustible heat source and the aerosol-forming substrate may have a low thermal conductivity or a high thermal conductivity. For example, the barrier can vary from about 0.1 W per meter Kelvin (W/(m K)) to about 200 W per meter Kelvin ( It may be formed of a material having a bulk thermal conductivity of W/(m·K)).

The thickness of the barrier between the rear end face of the combustible heat source and the aerosol-forming substrate may be selected to achieve good performance. For example, the barrier can have a thickness of about 10 μm to about 500 μm.

The barrier between the rear end face of the combustible heat source and the aerosol-forming substrate may be formed of one or more suitable materials that are substantially thermally stable and non-combustible at the temperatures achieved thereby during ignition and combustion of the combustible heat source. Suitable materials are known in the art and include, for example, clays such as bentonite and kaolinite; glass; mineral; ceramic material; Suzy; metal; or any combination thereof.

Preferably, the barrier comprises aluminum foil.

The barrier of aluminum foil may be applied by adhesion to the rear end face of the combustible heat source or by pressing it to the combustible heat source. The barrier may be cut or otherwise machined such that the aluminum foil covers and attaches at least substantially all of the rear end face of the combustible heat source. Advantageously, the aluminum foil is attached to cover the entire rear end face of the combustible heat source.

The aerosol-generating article according to the invention may comprise an unblind combustible heat source according to the invention.

When the combustible heat source is an unblind combustible heat source, air drawn through the aerosol-generating article for inhalation by a user in use passes through at least one airflow channel along the length of the combustible heat source.

When the combustible heat source is an unblind combustible heat source, heating of the aerosol-forming substrate occurs by conduction and forced convection.

When an aerosol-generating article according to the present invention comprises an unblind combustible heat source according to the present invention and a non-combustible substantially air impermeable barrier between the rear end face of the combustible heat source and the aerosol-forming substrate, the barrier is formed along the length of the combustible heat source. Air drawn through the at least one extending airflow channel should be drawn downstream through the aerosol-generating article.

Preferably, the aerosol-generating article according to the invention comprises a blind combustible heat source according to the invention.

When the combustible heat source is a blind heat source, air drawn through the aerosol-generating article for inhalation by a user in use does not pass through any airflow channels along the length of the blind combustible heat source.

When the combustible heat source is a blind combustible heat source, heating of the aerosol-forming substrate occurs primarily by conduction, and heating of the aerosol-forming substrate by forced convection is minimized or reduced. In such embodiments, it is particularly important to optimize the conductive heat transfer between the combustible heat source and the aerosol-forming substrate.

The lack of any airflow channels extending along the length of the combustible heat source through which air may be drawn for inhalation by the user may advantageously substantially prevent or inhibit activation of combustion of the blind combustible heat source during puff by the user. have. This may advantageously substantially prevent or inhibit the temperature spike of the aerosol-forming substrate during puffing by the user.

By preventing or inhibiting the combustion activation of the blind combustible heat source, and thus preventing or suppressing an excessive increase in temperature of the aerosol-forming substrate, combustion or pyrolysis of the aerosol-forming substrate under intense puffing regimes can be advantageously avoided. In addition, the effect of the user's puffing regime on the composition of the mainstream aerosol can advantageously be minimized or reduced.

The inclusion of a blind combustible heat source may advantageously substantially prevent or inhibit the entry of combustion and decomposition products and other materials formed during ignition and combustion of the blind combustible heat source into the air drawn through the aerosol-generating article for inhalation by a user. can

When the combustible heat source is a blind combustible heat source, the aerosol-generating article according to the invention comprises one or more air inlets downstream of the blind combustible heat source for drawing air into the aerosol-generating article for inhalation by a user.

In such embodiments, air drawn by a user through the aerosol-generating article for inhalation enters the aerosol-generating article through one or more air inlets without passing through the distal end of the aerosol-generating article.

Where the combustible heat source is an unblind combustible heat source, the aerosol-generating article according to the invention may also comprise one or more air inlets downstream of the unblind combustible heat source for drawing air into the aerosol-generating article for inhalation by a user. .

Aerosol-generating articles according to the present invention may comprise one or more air inlets around the periphery of the aerosol-forming substrate.

In this embodiment, while the user puffs, cold air is drawn into the aerosol-forming substrate of the aerosol-generating article through one or more air inlets on the perimeter adjacent to the aerosol-forming substrate. This advantageously reduces the temperature of the aerosol-forming substrate and thus can substantially prevent or inhibit the temperature spike of the aerosol-forming substrate during puffs by the user.

As used herein in connection with the present invention, the term “cold air” is used to describe ambient air that is not significantly heated by a combustible heat source upon puffing by a user.

By preventing or suppressing temperature spikes of the aerosol-forming substrate, the inclusion of one or more air inlets around the perimeter of the aerosol-forming substrate may advantageously help avoid or reduce pyrolysis or combustion of the aerosol-forming substrate under vigorous puffing regimes.

The inclusion of one or more air inlets around the perimeter of the aerosol-forming substrate may advantageously help minimize or reduce the impact of the user's puffing regime on the composition of the mainstream aerosol of the aerosol-generating article.

In certain preferred embodiments, an aerosol-generating article according to the invention may comprise one or more air inlets located proximate the downstream end of the aerosol-forming substrate.

Aerosol-generating articles according to the present invention may have any desired length.

For example, an aerosol-generating article according to the present invention may have a length of from about 65 mm to about 100 mm.

Aerosol-generating articles according to the present invention may have any desired width.

For example, an aerosol-generating article according to the present invention may have a width of about 5 mm to about 12 mm.

Aerosol-generating articles according to the invention can be assembled using known methods and machinery.

For the avoidance of doubt, where applicable, the features described above with respect to the combustible heat source according to the invention may also be applied to the aerosol-generating article according to the invention and vice versa.

The invention will be further described by way of example only with reference to the accompanying drawings, wherein
1 shows a schematic longitudinal cross-section of an aerosol-generating article according to an embodiment of the present invention;
2 shows a graph of calcium peroxide content as a function of time of a combustible heat source according to one embodiment of the present invention and a comparative combustible heat source not according to the present invention.

The aerosol-generating article 2 according to the embodiment of the invention shown in FIG. 1 comprises a combustible heat source 4 according to the invention and an aerosol-forming substrate 10 downstream of the combustible heat source 4 . The combustible heat source 4 is a blind combustible heat source having a front end face 6 and an opposing rear end face 8 and is located at the distal end of the aerosol-generating article 2 . The aerosol-generating article 2 further comprises a delivery element 12 , an aerosol cooling element 14 , a spacer element 16 and a mouthpiece 18 . The combustible heat source 4 , the aerosol-forming substrate 10 , the delivery element 12 , the aerosol cooling element 14 , the spacer element 16 and the mouthpiece 18 are arranged abutting in a coaxial alignment. 1 , the rear portion of the aerosol-forming substrate 10 , the delivery element 12 , the aerosol cooling element 14 , the spacer element 16 and the mouthpiece 18 and the combustible heat source 4 is an example It is wrapped with an outer wrapper 20 of a sheet material such as, for example, cigarette paper.

1 , a non-combustible substantially air impermeable barrier 22 in the form of a disk of aluminum foil is provided between the rear end face 8 of the combustible heat source 4 and the aerosol-forming substrate 10 . . A barrier 22 is applied to the rear end face 8 of the combustible carbonaceous heat source 4 by pressing a disc of aluminum foil onto the rear end face 8 of the combustible carbonaceous heat source 4 , ) abuts the rear end face 8 and the aerosol-forming substrate 10 .

The combustible heat source (4) comprises carbon, an alkaline earth metal peroxide ignition aid, and at least one additional selected from the group consisting of carboxymethyl cellulose and ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose. A combination of cellulose ethers includes a binder.

The aerosol-forming substrate 10 is positioned immediately downstream of the barrier 22 applied to the rear end face 8 of the combustible heat source 4 . The aerosol-forming substrate 10 includes a corrugated crimped sheet 24 of homogenised tobacco material and a wrapper 26 surrounding and in direct contact with the corrugated crimped sheet 24 of homogenised tobacco material. The corrugated crimped sheet 24 of homogenised tobacco material comprises a suitable aerosol former such as, for example, glycerin.

The delivery element 12 is positioned immediately downstream of the aerosol-forming substrate 10 and comprises a cylindrical open end hollow cellulose acetate tube 28 .

The aerosol cooling element 14 is located immediately downstream of the delivery element 12 and comprises a corrugated sheet of a biodegradable polymer material such as, for example, polylactic acid.

The spacer element 16 is positioned immediately downstream of the aerosol cooling element 14 and comprises a cylindrical, open-ended hollow paper or cardboard tube.

The mouthpiece 18 is located immediately downstream of the spacer element 16 . 1 , a mouthpiece 18 is positioned at the proximal end of the aerosol-generating article 2 and wrapped within a filter plug wrap 32 , such as, for example, a very low filtration efficiency cellulose acetate tow. A cylindrical plug of suitable filtration material 30 is included.

The aerosol-generating article may further comprise a band of tipping paper (not shown) circumscribing the downstream distal end of the outer wrapper 20 .

1 , the aerosol-generating article 2 is around and in contact with, for example, the rear portion 4b of the combustible heat source 4 and the front portion 10a of the aerosol-forming substrate 10 . It further includes a heat-conducting element 34 formed of a suitable heat-conducting material, such as aluminum foil. In the aerosol-generating article 2 according to the embodiment of the invention shown in FIG. 1 , the aerosol-forming substrate 10 extends downstream beyond the heat-conducting element 34 . That is, the heat-conducting element 34 is not around and not in contact with the rear portion of the aerosol-forming substrate 10 . However, it will be appreciated that in other embodiments of the present invention (not shown), the heat-conducting element 34 may be around and in contact with the entire length of the aerosol-forming substrate 10 . It will also be appreciated that in other embodiments of the present invention (not shown), one or more additional heat-conducting elements overlying heat-conducting element 34 may be provided.

The aerosol-generating article 2 according to the embodiment of the invention shown in FIG. 1 comprises one or more air inlets 36 around the periphery of the aerosol-forming substrate 10 . As shown in FIG. 1 , a circumferential arrangement of an air inlet 36 is provided within the wrapper 26 and the overlaid outer wrapper 20 of the aerosol-forming substrate 10 for cold air (shown by dashed arrows in FIG. 1 ). ) into the aerosol-forming substrate 10 .

In use, the user ignites the combustible carbonaceous heat source 4 . Once the combustible carbonaceous heat source 4 is ignited, the user draws on the mouthpiece 18 of the aerosol-generating article 2 . When the user inhales on the mouthpiece 18 , cold air (shown by the dashed arrow in FIG. 1 ) is drawn through the air inlet 36 into the aerosol-forming substrate 10 of the aerosol-generating article 2 .

The perimeter of the front portion 10a of the aerosol-forming substrate 10 is heated by conduction through the barrier 22 and the rear end face 8 of the combustible heat source 4 and through the heat-conducting element 34 .

Heating of the aerosol-forming substrate 10 by conduction releases the aerosol former and other volatile and semi-volatile compounds from the crimped crimped sheet of homogenised tobacco material 24 . The compound released from the aerosol-forming substrate 10 is entrained in air drawn into the aerosol-forming substrate 10 of the aerosol-generating article 2 through the air inlet 36 as air flows through the aerosol-forming substrate 10. form an aerosol; Aspirated air and entrained aerosols (shown by dashed arrows in FIG. 1 ) are combined with a hollow cellulose acetate tube 28 at the cylindrical open end of the delivery element 12 , an aerosol cooling element 14 and a spacer element 16 . passing downstream through the , where they cool and condense. The cooled aspirated air and the entrained aerosol pass downstream through the mouthpiece 18 and delivered to the user through the proximal end of the aerosol-generating article 2 . A non-combustible substantially air impermeable barrier 22 on the rear end face 8 of the combustible carbonaceous heat source 4 isolates the combustible heat source 4 from air drawn through the aerosol-generating article 2 in use, Air drawn through the aerosol-generating article 2 is not in direct contact with the combustible heat source 4 .

Certain embodiments and implementations described above are illustrative of, but not limiting of, the present invention. It is to be understood that other embodiments of the invention may be made and that certain embodiments and embodiments described herein are not exhaustive.

A combustible heat source according to the invention having the composition shown in Table 1 was prepared:

The components in Table 1 are combined to form a granule mixture by wet granulation. Charcoal, calcium peroxide and carboxymethyl cellulose are mixed to form a particulate mixture. A particulate mixture of charcoal, calcium peroxide and carboxymethyl cellulose is air fluidized and sprayed with a liquid solution of potassium tri-citrate hydrate and an aqueous solution of hydroxypropyl cellulose to form a granular mixture.

The granule mixture is formed into a cylindrical shape by pressing. About 400 mg of the granular mixture is pressed in a single cavity press to produce a cylindrical combustible heat source having a length of about 9 mm, a width of about 7.7 mm and a density of about 0.9 g/cm3. The cylindrical combustible heat source is removed from the single cavity press and dried in a drying oven at a temperature of about 85° C. to about 105° C. for about 3 hours.

Comparative combustible heat sources not according to the invention having the compositions shown in rows A, B and C of Table 2 are also prepared:

The components in Table 2 are combined to form a granule mixture by wet granulation. Charcoal, calcium peroxide and carboxymethyl cellulose are mixed to form a particulate mixture. A particulate mixture of charcoal, calcium peroxide and carboxymethyl cellulose is air fluidized and sprayed with a liquid solution of potassium tri-citrate hydrate and then an aqueous solution of bentonite to form a granular mixture.

The granule mixture is formed into a cylindrical shape by pressing. About 400 mg of the granular mixture is pressed in a single cavity press to produce a cylindrical combustible heat source having a length of about 9 mm, a width of about 7.7 mm and a density of about 0.9 g/cm3. The cylindrical combustible heat source is removed from the single cavity press and in a drying oven at a temperature of about 85° C. to about 105° C. for about 3 hours.

To simulate the environmental conditions to which a combustible heat source may be exposed during transportation and storage, a combustible heat source according to the present invention and a comparative combustible heat source not according to the present invention are conditioned at about 30° C. and about 75% relative humidity for 7 days. The calcium peroxide content (% by weight) of the combustible heat source according to the invention and the comparative combustible heat source not according to the invention is determined as a function of time by titration with a solution of potassium permanganate (KMnO ₄ ). The results are presented in FIG. 2 ; The upper line labeled I in FIG. 2 shows the measured calcium peroxide content of a combustible heat source according to the invention as a function of time, and the lower line labeled A, B and C in FIG. 2 is a comparison not according to the invention The measured calcium peroxide content of a combustible heat source is plotted as a function of time. The values shown in Figures 2 and 3 are the average of measurements for three replicates of each combustible heat source.

As shown in Figure 2, the rate of degradation over time of calcium peroxide in a combustible heat source according to the invention is advantageously significantly lower than the rate of degradation over time of calcium peroxide in a comparative combustible heat source not according to the invention.

The ignition propagation velocities of 10 combustible heat sources according to the invention and 10 comparative combustible heat sources not according to the invention having the composition shown in column A of Table 2 were also measured. The results are shown in Table 3. A combustible heat source according to the present invention and a comparative combustible heat source not according to the present invention are conditioned at about 22° C. and about 50% relative humidity for about 24 hours prior to measurement of the ignition propagation rate. To measure the ignition propagation velocity, a thermocouple is inserted at two positions into a combustible heat source according to the present invention and a comparative combustible heat source not according to the present invention, the first position being 1 mm from the front end face of the combustible heat source and the second position being the second position. The location is 8 mm from the front end face of the combustible heat source. The front end faces of the combustible heat source according to the present invention and the comparative combustible heat source not according to the present invention are ignited using an electric lighter. The difference in the time it takes for the temperature measured by the thermocouple at the first position and the second position to reach 350°C is measured. The ignition propagation times shown in Table 3 are the average times measured for 10 combustible heat sources according to the invention and 10 comparative combustible heat sources not according to the invention.

As shown in Table 3, the ignition propagation time of a combustible heat source according to the invention is advantageously significantly lower than that of a comparative combustible heat source not according to the invention.

The results in Figure 2 and Table 3 demonstrate the improvement of the chemical and physical stability and combustion properties of the combustible heat source according to the present invention due to the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether.

The results of Figure 2 show that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether in a combustible heat source according to the present invention advantageously reduces the degradation of the alkaline earth metal peroxide ignition aid as a result of exposure to environmental conditions. It has been shown to significantly reduce In particular, the results of Figure 2 show that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether in the combustible heat source according to the present invention is advantageously the result of exposure to high humidity of the alkaline earth metal peroxide ignition aid. It proves to significantly reduce degradation.

The results in Table 3 show that the inclusion of a binder comprising a combination of carboxymethyl cellulose and at least one further cellulose ether in the combustible heat source according to the invention also advantageously significantly improves the rate of propagation of ignition of the combustible heat source according to the invention. prove it

Claims (15)

A combustible heat source for an aerosol-generating article, the combustible heat source comprising:
carbon;
alkaline earth metal peroxide ignition aids; and
A combustible heat source comprising a binder comprising a combination of carboxymethyl cellulose and at least one additional cellulose ether. The combustible heat source of claim 1 , wherein the at least one additional cellulose ether is selected from the group consisting of ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose. The combustible heat source of claim 1 , wherein the ratio of the weight percent of carboxymethyl cellulose to the weight percent of the at least one additional cellulose ether in the combustible heat source is at least about 1:1. The combustible heat source according to any one of claims 1 to 3, wherein the alkaline earth metal peroxide ignition aid is calcium peroxide. 5. The combustible heat source according to any one of claims 1 to 4, wherein the combustible heat source comprises at least about 15% by weight of an alkaline earth metal peroxide ignition aid. 6. The combustible heat source according to any one of claims 1 to 5, wherein the combustible heat source comprises from about 20% to about 60% by weight of an alkaline earth metal peroxide ignition aid. 7. The combustible heat source according to any one of claims 1 to 6, wherein the combustible heat source comprises at least about 3 weight percent binder. 8. The combustible heat source according to any one of claims 1 to 7, wherein the combustible heat source comprises from about 4% to about 15% by weight binder. 9. The combustible heat source according to any one of claims 1 to 8, wherein the combustible heat source comprises at least about 0.2 weight percent of at least one additional cellulose ether. 10. The combustible heat source according to any one of claims 1 to 9, wherein the combustible heat source comprises from about 0.75% dry to about 5% by weight of at least one additional cellulose ether. 11. The combustible heat source according to any one of the preceding claims, wherein the carboxymethyl cellulose is present in the combustible heat source in an amount of at least about 1.5 dry weight percent. 12. The combustible heat source according to any one of claims 1 to 11, wherein the combustible heat source comprises at least about 25 weight percent carbon. 13. The combustible heat source according to any one of claims 1 to 12, wherein the combustible heat source comprises from about 30% to about 55% by weight carbon. 14. The combustible heat source according to any one of claims 1 to 13, further comprising one or more carboxylate combustion salts. An aerosol-generating article comprising:
15. A combustible heat source according to any one of claims 1 to 14; and
an aerosol-generating article comprising an aerosol-forming substrate downstream of said combustible heat source.

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