KR20220092568A - Aerosol-forming Substrates Having Nitrogen-Containing Nucleophilic Compounds - Google Patents

Abstract

The present invention relates to an aerosol-forming substrate comprising:
a) one or both of cellulose and cellulose derivatives;
b) an aerosol former;
c) 0% to 5% by weight, preferably 0% to 3% by weight, more preferably 0% to 1% by weight, most preferably 0% to 5% by weight, based on dry weight based on the total amount of the aerosol-forming substrate 0% to 0.5% by weight of tobacco, and
d) nitrogen-containing nucleophilic compounds.

Description

Aerosol-forming Substrates Having Nitrogen-Containing Nucleophilic Compounds

The present invention relates to a system comprising an aerosol-forming substrate, an aerosol-generating article comprising a substrate portion comprising the aerosol-forming substrate, and an aerosol-generating device comprising the aerosol-forming article and a heating chamber for inserting the aerosol-generating article.

It is known to provide an aerosol-generating article comprising an aerosol-forming substrate comprising a polyhydric alcohol and an aerosol former such as nicotine. The aerosol-generating article is inserted into a heating chamber of the aerosol-generating device and heated to a temperature at which one or more components of the aerosol-forming substrate volatilize without burning the aerosol-forming substrate. These non-liquid aerosol-generating articles may or may not contain tobacco. It is known that aldehydes, particularly unwanted formaldehyde, can be formed when smoking cigarettes in traditional cigarettes. However, aldehydes can also be formed when heating an aerosol-generating article without burning the aerosol-forming substrate. Accordingly, there is a need to reduce the formation of unwanted aldehydes in the aerosol generated by heating the aerosol-forming substrate without burning.

According to one embodiment of the present invention, there is provided an aerosol-generating substrate comprising:

a) cellulose and/or cellulose derivatives;

b) an aerosol former;

c) 0% to 5% by weight, preferably 0% to 3% by weight, more preferably 0% to 1% by weight, most preferably 0% to 1% by weight, based on dry weight, based on the total amount of the aerosol-forming substrate 0% to 0.5% by weight of tobacco, and

d) nitrogen-containing nucleophilic compounds.

Surprisingly, it has been found that an aerosol-forming substrate comprising cellulose and/or cellulose derivatives, which is tobacco free or substantially free of tobacco, can generate aerosols with high concentrations of aldehydes, in particular formaldehyde. The aerosol-forming substrate may comprise 0.1 wt% to 3 wt%, 0.2 wt% to 2.5 wt%, or 0.3 wt% to 2 wt% tobacco. The concentration of formaldehyde in the aerosol formed from such aerosol-forming substrates can be several times higher than the concentration of formaldehyde in the aerosol of an aerosol-generating article containing greater than 70% by weight tobacco.

The nitrogen-containing nucleophilic compound can provide an aerosol with a reduced amount of aldehyde as compared to an aerosol-forming substrate that does not contain the nitrogen-containing nucleophilic compound. In addition, nitrogen-containing nucleophilic compounds can provide aldehyde-free aerosols. Without being bound by any theory, the nitrogen-containing nucleophilic compound may react with the aldehyde in the aerosol, or reduce or inhibit the in situ formation of the aldehyde in the aerosol-forming substrate. Thus, nitrogen-containing nucleophilic compounds can act as aldehyde scavengers. Thus, any aerosol generated from the aerosol-forming substrate described above may contain less aldehyde compared to an aerosol-forming substrate of the same composition, but lack the nitrogen-containing nucleophilic compound.

Without being bound by any theory, the nitrogen-containing nucleophilic compound may react via a nitrogen atom with an aldehyde, particularly formaldehyde, present in the aerosol. Compounds may be particularly nucleophilic due to the single electron pair of the nitrogen atom.

Nitrogen-containing nucleophilic compounds may include groups such as *-NH ₂ , *-NH-*, *-CN, NH ₄ ⁺ , or *-C(=O)-NH-*, wherein the bond "*- " indicates binding to an additional moiety of the nitrogen-containing nucleophilic compound. Without wishing to be bound by any theory, these nitrogen atom-containing groups may react well with any aldehyde or chemical precursor to these aldehydes, particularly formed upon heating of the aerosol-forming substrate.

According to another embodiment of the present invention, the nitrogen-containing nucleophilic compound may be an organic and/or inorganic compound. In particular, the nitrogen-containing nucleophilic compound may be selected from the group consisting of:

- an organic compound having an amino group or an amide group, preferably an amino group, nitrogen-containing saccharides and polysaccharides, or nitrogen-containing plastics;

- and inorganic ammonium compounds;

- or a combination thereof.

According to a further embodiment of the present invention, the nitrogen-containing nucleophilic compound may be selected from at least one of:

- an amino acid selected from the group consisting of lysine, glycine, cysteine, arginine, or homocysteine or combinations thereof,

- tripeptides including glutathione;

- urea or urea derivatives or combinations thereof;

- nitrogen-containing saccharides and polysaccharides selected from the group consisting of glucosamine, galactosamine, or chitosan, or combinations thereof,

- a nitrogen-containing plastic selected from polyethylene-imine, polystyrene-acrylonitrile or polyacrylonitrile butadiene-styrene or combinations thereof.

These compounds may be particularly suitable for reacting with aldehydes. Thus, these compounds can reduce the concentration of aldehydes, particularly formaldehyde in aerosols formed from these aerosol-forming substrates.

Compounds such as lysine, urea, chitosan, polyethylene-imine and di-ammonium phosphate or combinations thereof may be particularly preferred.

The tripeptide comprising glutathione may preferably be glutathione.

The urea derivative may be selected from derivatives, wherein some or all of the hydrogen atoms of the —NH ₂ group are substituted with a C ₁ to C ₁₂ -alkyl group, an aryl group, a hydrogen group or an alkyl-hydroxy group. Specific examples may be N-hydroxy urea, N-alkyl urea or N-aryl urea, or any combination thereof.

The aerosol-forming substrate comprises, based on the total amount of the aerosol-forming substrate, 0.1% to 10% by weight, 0.2% to 9% by weight, preferably 0.5% to 8% by weight, most preferably 1% by weight, based on the total amount of the aerosol-forming substrate. % to 5% by weight, even more preferably from 1% to 4% by weight, or from 1.5% to 3% by weight of a nitrogen-containing nucleophilic compound. These weight percent ranges can be particularly advantageous for reducing the amount of aldehydes, particularly formaldehyde in the aerosol formed. Particular preference may also be in the weight-% range from 2% to 4% by weight. This range can reduce or completely eliminate aldehydes in the aerosol formed.

The cellulose present in the aerosol-forming substrate of the present invention may act as a filler. In particular, cellulose may serve as a matrix for aerosol formers that may be present in the aerosol-forming substrate. Cellulose may include particles having a size of less than 100 micrometers. Cellulose may be in powder form.

Cellulose may include cellulosic fibers. The cellulosic fibers may have a length greater than 200 micrometers. Fiber length can vary from 200 to 2000 micrometers. Fiber length can vary from 14 to 32 micrometers. Cellulose fibers can act as an agent to reinforcing the aerosol-forming substrate.

The cellulose derivative may be a derivative in which the -OH group of the D-glucose unit of cellulose is at least partially or completely substituted with a group other than the -OH group. In a preferred embodiment, the cellulose derivative may be a cellulose ester and a cellulose ether.

Typical cellulose esters may be cellulose acetate, cellulose propionate or cellulose sulfate. A typical cellulose ether may be a cellulose ether, wherein some or all of the hydrogen atoms of the —OH group have been substituted with an alkyl group, or a carboxy alkyl group. Suitable examples of the group of cellulose ethers may be methyl cellulose, ethyl cellulose, hydroxy ethyl cellulose, hydroxy propyl cellulose, ethyl hydroxy ethyl cellulose or carboxymethyl cellulose (CMC) or any combination thereof. Particularly preferred may be carboxymethyl cellulose. The cellulose derivative may act as a binder in the aerosol-forming substrate.

Cellulose and/or cellulose is present in an amount of from 15% to 85% by weight, preferably from 20% to 80% by weight, more preferably from 25% to 70% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. may be present in quantity. These weight percent ranges may be particularly suitable for cellulose and/or cellulose derivatives to act as binders or fillers.

In particular, the cellulose is present in an amount of 30% to 70% by weight, preferably in an amount of 35% to 65% by weight, more preferably in an amount of 30% to 58% by weight, even more preferably 40% by weight. It may be present in an amount of from 40% to 60% by weight, most preferably from 40% to 50% by weight. In particular, there may be an amount of cellulose from 45% to 58% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. These weight percent ranges are preferred for cellulose and allow the cellulose to function particularly well as a filler in an aerosol-forming substrate.

The cellulose derivative is present in an amount of from 1% to 15% by weight, or from 1.5% to 12% by weight, preferably from 2% to 10% by weight, more preferably from 2.5% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. % to 8% by weight, more preferably from 3% to 5% by weight.

The cellulosic fibers are present in an amount of from 0.5% to 10% by weight, preferably from 1% to 8% by weight, more preferably from 2% to 6% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate, Most preferably, it may be present in an amount of 2.5% to 5.5% by weight. These weight percent ranges allow the fibers to serve particularly well as reinforcing agents for aerosol-forming substrates.

In a further embodiment of the invention, one, two or all of cellulose powder, cellulose fibers and cellulose derivatives may be present in the aerosol-forming substrate. For example, the aerosol-forming substrate may comprise a combination of cellulose powder and a cellulose derivative such as carboxymethyl cellulose. Alternatively, the aerosol-forming substrate may comprise a combination of cellulosic powder and cellulosic fibers. Alternatively, the aerosol-forming substrate may comprise a combination of cellulosic fibers and cellulose derivatives. Further, the aerosol-forming substrate may comprise only cellulose powder. The aerosol-forming substrate may comprise only cellulose fibers or cellulose derivatives. In particular, cellulose powder, cellulose fibers and cellulose derivatives such as carboxymethyl cellulose may be included in the aerosol-forming substrate. The presence of all three components may enable them to act as reinforcing agents, fillers, and binders.

The aerosol-forming substrate may comprise at least one aerosol-forming agent. An aerosol former is any suitable known compound or mixture of compounds that, in use, facilitates the formation of a dense and stable aerosol and substantially resists thermal degradation at the operating temperature of the aerosol generating system. Suitable aerosol formers include polyhydric alcohols such as triethylene 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. The aerosol former may be a polyhydric alcohol or mixtures thereof, such as triethylene glycol, 1,3-butanediol and glycerin. The aerosol former may be propylene glycol. The aerosol former may include both glycerin and propylene glycol. The aerosol former may be glycerin alone.

The aerosol former is present in an amount of from 20% to 58%, preferably from 25% to 45%, more preferably from 30% to 38% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. can Throughout this application the term "by dry weight " refers to the weight of an aerosol-forming substrate calculated as water removed via Karl-Fischer titration, for example heated to a temperature of 110° C. at standard conditions for temperature and pressure and ending point An electrometer is used to determine The endpoint is detected by double potentiometric titration. A second pair of Pt electrodes is immersed in the anode solution. The detector circuit maintains a constant current between the two detector electrodes during titration. Before the equivalence point, the solution contains I ⁻ but little I ₂ . At the equivalence point, excess I ₂ appears, and a sharp voltage drop marks the end point. Then, I ₂ is generated and the endpoint is The amount of charge required to reach can be used to calculate the amount of water in the original sample. The aerosol former content can be determined by gas chromatography in combination with a flame ionization detector.

In some embodiments, the aerosol-forming substrate may further comprise a disaccharide. In a preferred embodiment, the aerosol-forming substrate may comprise a disaccharide. Without being bound by any theory, the disaccharide may serve to facilitate heat conduction from the external heating element to the aerosol-forming substrate. Thus, the disaccharide can aid in the reliable formation of an aerosol when the aerosol-forming substrate is heated within the heating chamber by any external heating element.

Also, without being bound by any theory, disaccharides may serve to modify the release of the aerosol former during the course of different puffs taken by the user. For example, the presence of disaccharides may enable release of an aerosol former, such as glycerin, over a longer and extended period of time. In particular, it may be possible for the user to enjoy the aerosol generated from the aerosol-forming substrate after taking more than 6, 7 or 8 puffs. In general, the amount of aerosol generated during these back puffs is reduced compared to the user's 3rd or 4th puff.

The disaccharide may be selected from sucrose, lactose or maltose or combinations thereof. In a preferred embodiment, the disaccharide is sucrose.

The disaccharide may be present in an amount of from 0.1% to 15% by weight, preferably from 0.5% to 12% by weight, more preferably from 1% to 10% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. have. These weight percent ranges allow the disaccharide to prolong the release of the aerosol former particularly well during puffs taken by the user. Also, these weight percent ranges may be well suited to enable conduction of heat into the aerosol-forming substrate.

In some embodiments, the aerosol-forming substrate may further comprise nicotine. Nicotine can form a significant part of the aerosol generated from the aerosol-forming substrate upon heating.

The aerosol-forming substrate is present in an amount of from 0.1% to 10% by weight, preferably from 0.5% to 8% by weight, more preferably from 1% to 3% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. may contain nicotine. The nicotine content by " dry weight " can also be detected by gas chromatography in combination with a flame ionization detector.

The aerosol-forming substrate may further comprise at least one carboxylic acid, preferably a C ₃ to C ₆ alkyl hydroxy carboxylic acid, an alkyl keto carboxylic acid or an aryl carboxylic acid. Such at least one carboxylic acid is capable of protonating any nicotine present in the aerosol-forming substrate. Specific examples of the carboxylic acid may be lactic acid, benzoic acid, citric acid, malic acid, tartaric acid, 2-methyl butyric acid, levulinic acid, or any combination thereof. Preferably, the nicotine is protonated with an acid in solution to obtain a nicotine salt. The nicotine salt can then be used together with other ingredients such as cellulose or cellulose derivatives to prepare an aerosol-forming substrate. For example, nicotine can be used as a 10 wt % solution in glycerin and 2 molar equivalents of lactic acid can be added to the slurry of the remaining ingredients and mixed. The one or more protonated nicotine salts may have a higher solubility in water as compared to nicotine free base. Preferably, the one or more nicotine salts may be selected from the list consisting of nicotine citrate, nicotine pyruvate, nicotine deuterate, nicotine pectate, nicotine alginate, and nicotine salicylate. These salt forms of nicotine are more stable than commonly used liquid free base nicotine. Accordingly, aerosol-forming substrates comprising one or more of these nicotine salts may have a longer shelf life than conventional aerosol-forming substrates.

The at least one carboxylic acid is present in an amount of from 0.1% to 10% by weight, preferably from 0.5% to 8% by weight, more preferably from 1% to 3% by weight on a dry weight basis, based on the total amount of the aerosol-forming substrate. can exist as

The aerosol-forming substrate may comprise a non-tobacco volatile flavor compound. These non-tobacco volatile flavor compounds can form an aerosol with the aerosol former upon heating of the aerosol-forming substrate. For example, the non-tobacco volatile flavor compound may include menthol. As used herein, the term 'menthol' refers to the compound 2-isopropyl-5-methylcyclohexanol in any isomeric form thereof. The non-tobacco volatile flavor compound may provide a flavor selected from the group consisting of menthol, lemon, vanilla, orange, wintergreen, cherry, and cinnamon.

The amount of non-tobacco volatile flavor compounds in the aerosol-forming substrate may be from 0.1% to 54% by weight, preferably from 0.5% to 30% by weight, on a dry weight basis, based on the total amount of the aerosol-forming substrate.

According to a further embodiment of the invention, the aerosol-forming substrate may comprise from 0.1% to 3% by weight of tobacco, preferably from 0.1% to 2% by weight of tobacco.

According to a further embodiment of the present invention, the aerosol-forming substrate is substantially free, more preferably free of any tobacco. In this case, the aerosol may be formed by the aerosol former, if present, by nicotine and/or non-tobacco volatile flavor compounds. The tobacco flavor compound may not contribute substantially or no to the formation of the aerosol when the aerosol-forming substrate is heated.

Cellulose and/or cellulose derivatives may be derived from cellulose sources other than tobacco. For example, trees or non-tobacco plants can serve as a source of cellulosic material. Accordingly, cellulose and/or cellulose derivatives may not be derived from tobacco.

The presence and absence of tobacco in the aerosol-forming substrate can also be identified as positive by DNA barcoding. Methods for performing DNA barcodes based on the plastid intergenic spacer trnH-psbA as well as the tobacco nuclear genes ITS2 (internal transcriptional spacer 2), rbcL and matK systems are well known and available in the art (Chen S, Yao H). , Han J, Liu C, Song J, et al. (2010) Validation of the ITS2 Region as a Novel DNA Barcode for Identifying Medicinal Plant Species.PLoSONE 5(1): e8613; Hollingsworth PM, Graham SW, Little DP (2011) Choosing and Using a Plant DNA Barcode.PLoS ONE 6(5): e19254).

The substrate portion comprising the aerosol-forming substrate may be formed as a sheet, preferably a cast sheet. The sheet of aerosol former is formed by casting a slurry comprising cellulose and/or a cellulose derivative, and -optionally- the aerosol former and a nitrogen-containing nucleophilic compound, onto a conveyor belt or other support surface, drying the cast slurry to form an aerosol It may be formed by a casting process of the type generally comprising the steps of forming a sheet of a forming substrate, and removing the sheet of aerosol-forming substrate from a support surface. For example, in certain embodiments a sheet of aerosol-forming substrate for use in the present invention may be formed by a casting process into a slurry comprising cellulose, cellulose fibers, carboxymethyl cellulose and optionally glycerin. Additionally, the slurry may comprise additional components selected from nicotine, nicotine salts, disaccharides.

In one embodiment, a slurry is formed comprising at least one of cellulose and cellulose derivatives, an aerosol former, a nitrogen-containing nucleophilic compound and - if present - tobacco. The components in the slurry may have a concentration of 15% to 25% by weight on a dry weight basis, preferably 20% by weight. The casting sheet may be formed from a slurry. The casting sheet may be formed by drying. The target sheet thickness may be between 200 micrometers and 300 micrometers, preferably 250 micrometers. The sheet weight may range from 160 to 180 grams per square meter.

Alternatively, the casting process for forming the sheet of non-tobacco material may use cellulose and/or cellulose derivatives. The cast sheet can then serve as a cellulosic absorbent substrate for absorbing nicotine, preferably one or both of the nicotine salt and the aerosol former onto the sheet. Additionally, nitrogen-containing nucleophilic compounds and/or disaccharides may also be adsorbed onto the absorbent substrate or may be present during the casting process.

The nicotine, preferably the nicotine salt, and the aerosol former may be combined with water as a liquid formulation. The liquid formulation may further comprise any one of the aforementioned non-tobacco volatile flavor compounds. This liquid formulation can then be absorbed by the absorbent substrate or coated onto the absorbent substrate surface.

The portion of the substrate comprising the aerosol-forming substrate may be formed as a rod. The substrate portion may be provided comprising a corrugated sheet of a non-tobacco material formed by the aforementioned casting process comprising cellulose and/or cellulose derivatives. The substrate portion may be surrounded by a wrapper. The sheet of non-tobacco material may be textured or crimped and include an absorbent substrate, a nicotine salt, and an aerosol former. The corrugated sheet of homogenised non-tobacco material preferably extends along substantially the entire length of the substrate portion and over substantially the entire cross-sectional area of the substrate portion. The sheet may further include water.

The aerosol-forming substrate may comprise up to 5% by weight of tobacco on a dry weight basis, based on the total amount of the aerosol-forming substrate. Such tobacco may include cast leaf tobacco, reconstituted tobacco, tobacco paper, tobacco powder, compounded tobacco, strip, sheet, shredded tobacco, or tobacco in any other suitable form. Tobacco may be made into sheets of homogenized tobacco material by a reconstitution process. These include, but are not limited to, a papermaking process of the type described, for example in US-A-3,860,012, or a casting or 'cast leaf' process, of the type described, for example, in US-US-A-5,724,998. For example, in certain embodiments, a homogenizing sheet comprising tobacco material for use in the present invention may be formed into a slurry further comprising particulate tobacco in addition to the other ingredients for the slurry described above.

As used herein, the term 'corrugated' refers to a sheet of aerosol substrate that is rolled, folded, or otherwise compressed or retracted substantially transverse to the cylindrical axis of the rod.

The term 'sheet' may refer to a laminate element having a width and length substantially greater than its thickness.

Another embodiment of the present invention relates to an aerosol-generating article comprising a substrate portion containing an aerosol-forming substrate as described herein. Preferably, the substrate portion in the article may be in the form of a rod.

The aerosol-generating article may further comprise a connection portion. The connection may preferably have a tubular hollow core. This tubular hollow core may be located downstream of the substrate portion and may abut the aerosol-forming substrate.

The connection may be formed of any suitable material or combination of materials. For example, the linkage may be cellulose acetate; cardboard; crimped paper, such as crimped heat-resistant paper or crimped sulfate paper; and polymeric materials, such as low density polyethylene (LDPE). In a preferred embodiment, the connecting portion may be formed of cellulose acetate, preferably a cellulose acetate hollow tube.

The connecting portion preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article.

The aerosol-generating article may further comprise a tipping paper arranged to be at least partially wrapped around the connection portion and the substrate portion to overlap the connection portion and the substrate portion. Such tipping paper may increase the stability of the aerosol-generating article.

The present invention also relates to an aerosol-generating system comprising an aerosol-generating device and an aerosol-generating article as described herein. The aerosol-generating device may comprise a heating element and a heating chamber for receiving the aerosol-generating article. The heating element may be configured to heat the aerosol-generating article to a temperature in the range from 220°C to 400°C, preferably from 250°C to 290°C. At these temperatures, an aerosol can be generated from an aerosol-forming substrate included in the aerosol-generating article. Such aerosols may be reduced in aldehydes due to the presence of nitrogen-containing nucleophilic compounds.

The aerosol-generating device can heat the aerosol-generating article, but does not burn it. Such electrically heated non-combustion heating aerosol-generating systems heat the aerosol-generating article to a temperature sufficient to generate an aerosol from the substrate without burning the substrate.

As used herein, the terms 'upstream', 'downstream' refer to aerosol-generating devices and components of aerosol-generating articles with respect to the direction in which a user draws an aerosol-generating article inserted into the heating chamber of the aerosol-generating device during use, Or used to describe the relative position of parts of a component.

The aerosol-generating article may comprise a mouth end through which, in use, the aerosol exits the aerosol-generating system and is delivered to the user. The mouth end may also be referred to as the downstream end. In use, the user draws on the aerosol-generating system, particularly downstream of the aerosol-generating article or on the mouth end, to inhale the aerosol generated by the aerosol-generating system. The aerosol-generating system includes an upstream end opposite the downstream or mouth end.

In some aspects of the present disclosure, the heating element may include an electrically resistive material. Suitable electrically resistive materials include, but are not limited to, semiconductors such as doped ceramics, electrically “conductive” ceramics (eg, molybdenum disilicide, etc.), carbon, graphite, metals, metal alloys, and composite materials consisting of ceramic materials metal materials. not limited Such composite materials may include doped ceramics or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbide. Examples of suitable metals include titanium, zirconium, tantalum, platinum, gold and silver. Examples of suitable metal alloys include stainless steel, nickel-, cobalt-, chromium-, aluminum-, titanium-, zirconium-, hafnium-, niobium-, molybdenum-, tantalum-, tungsten-, tin-, gallium-, manganese- , gold- and iron-containing alloys, and superalloys based on nickel, iron, cobalt, stainless steel, Timetal® and iron-manganese-aluminum based alloys. For the composite material, the electrically resistive material may be selectively embedded in the insulating material, encapsulated or coated with the insulating material, or vice versa, depending on the energy transfer kinetics and the required external physicochemical properties.

In another embodiment, a heated aerosol-generating article can be used comprising a combustible heat source and an aerosol-generating substrate downstream of the combustible heat source. For example, an aerosol-generating article may be used with an aerosol-generating substrate in a heated aerosol-generating article of the type disclosed in WO-A-2009/022232, which comprises a combustible carbon-based heat source, an aerosol-forming substrate downstream of the combustible heat source; and a heat-conducting element around and in contact with the rear portion of the combustible carbon-based heat source and the adjacent front portion of the aerosol-forming substrate. However, it will be understood that the aerosol-generating articles entitled herein may be used within heated aerosol-generating articles comprising combustible heat sources having other configurations.

As explained, in any of the aspects of the present disclosure, the heating element may be part of an aerosol-generating device. An aerosol-generating device may include an internal heating element or an external heating element, or both internal and external heating elements, where “internal” and “external” refer to an aerosol-generating article. The internal heating element may take any suitable form. For example, the internal heating element may take the form of a heating blade. Alternatively, the internal heater may take the form of a casing or substrate having different conductivity, or an electrically resistive metal tube. Alternatively, the internal heating element may be one or more heating needles or rods passing through the center of the substrate portion of the aerosol-generating article. Other alternatives include heating wires or filaments such as nickel-chromium (Ni-Cr), platinum, tungsten or alloy wires or heating plates. Optionally, the internal heating element may be deposited in or over the rigid carrier material. In one such embodiment, the electrically resistive heating element may be formed using a metal having a defined relationship between temperature and resistivity. In this exemplary arrangement, the metal may be formed as a track on a suitable insulating material, such as a ceramic material, and then interposed in another insulating material, such as glass. A heater formed in this way can be used to both heat the heating element and monitor the temperature of the heating element during operation.

The external heating element may take any suitable form. For example, the external heating element may take the form of one or more flexible heating foils on a dielectric substrate such as polyimide. The flexible heating foil may be shaped to conform with the perimeter of the heating chamber to receive the aerosol-generating article. Alternatively, the external heating element may take the form of a metal grid or grids, a flexible printed circuit board, a molded interconnect device (MID), a ceramic heater, a flexible carbon fiber heater, or on a substrate of a suitable shape. It can be formed using a coating technique such as plasma vapor deposition. The external heating element may also be formed using a metal having a defined relationship between temperature and resistivity. In this exemplary arrangement, the metal may be formed as a track between two layers of suitable insulating material. An external heating element formed in this way can be used both for heating the external heating element during operation and for monitoring the temperature of the external heating element.

The internal or external heating element may comprise a heat sink, or heat reservoir, comprising a material capable of absorbing and storing heat and subsequently dissipating heat over time to a substrate portion of the aerosol-generating article. The heat sink may be formed of any suitable material, such as a suitable metal or ceramic material. In one embodiment, the material has a high heat capacity (sensible heat storage material) or is a material capable of absorbing and subsequently releasing heat through a reversible process such as a high temperature phase change. Suitable sensible heat storage materials include silica gel, alumina, carbon, glass mats, glass fibers, minerals, metals or alloys such as aluminum, silver or lead, and cellulosic materials such as paper. Other suitable materials that dissipate heat through a reversible phase change include paraffin, sodium acetate, naphthalene, wax, polyethylene oxide, metals, metal salts, mixtures or alloys of eutectic salts. The heat sink or heat reservoir may be arranged to directly contact the substrate portion of the aerosol-generating article and transfer stored heat directly to the substrate. Alternatively, heat stored in a heat sink or heat reservoir may be transferred to the substrate portion of the aerosol-generating article by a thermal conductor, such as a metal tube.

Alternatively to an electrically resistive heating element, the heating element may be configured as an induction heating element. The induction heating element may include an induction coil and a susceptor. In general, a susceptor is a material that can absorb electromagnetic energy and convert it into heat. When placed in an alternating electromagnetic field, an eddy current is typically induced in the susceptor, resulting in hysteresis losses resulting in heating of the susceptor. Altering the electromagnetic field generated by one or several induction coils heats the susceptor, which in turn transfers the heat to the aerosol-generating article to form an aerosol. Heat transfer may be primarily by conduction of heat. This heat transfer is best when the susceptor is in close thermal contact with the aerosol-generating article.

The susceptor may be formed of any material capable of induction heating from the aerosol-forming substrate to a temperature sufficient to generate an aerosol. A preferred susceptor may comprise or consist of a ferromagnetic material, for example a ferromagnetic alloy, ferritic iron or ferromagnetic steel or stainless steel. A suitable susceptor may be or include aluminum. Preferred susceptors can be heated to temperatures in excess of 250°C.

A preferred susceptor is a metal susceptor, for example stainless steel. However, susceptor materials may also include graphite, molybdenum, silicon carbide, aluminum, niobium, inconel alloys (austenitic nickel-chromium-based superalloys), metallized films, ceramics such as zirconia, for example iron, It may contain or be made of a transition metal such as cobalt, nickel, or a metalloid component such as, for example, boron, carbon, silicon, phosphorus, or aluminum.

Preferably, the susceptor material is a metallic susceptor material. The susceptor may be a multi-material susceptor and may include a first susceptor material and a second susceptor material. In some implementations, the first susceptor material may be disposed in intimate physical contact with the second susceptor material. Preferably, the Curie temperature of the second susceptor material is below the flash point of the aerosol-forming substrate. When the susceptor is placed in the fluctuating electromagnetic field, the first susceptor material is preferably primarily used to heat the susceptor. Any suitable material may be used. For example, the first susceptor material may be aluminum or may be a ferrous material such as stainless steel. Preferably, the second susceptor material is mainly used to indicate when the susceptor has reached a specific temperature that is the Curie temperature of the second susceptor material. The Curie temperature of the second susceptor material may be used to adjust the temperature of the entire susceptor during operation. Suitable materials for the second susceptor material may include nickel and certain nickel alloys.

By providing at least first and second susceptor materials, heating and heating temperature control of the aerosol-forming substrate may be separated. The second susceptor material is preferably a magnetic material having a second Curie temperature substantially equal to the desired maximum heating temperature. That is, the second Curie temperature is preferably approximately equal to the temperature to which the susceptor must be heated in order to generate an aerosol from the aerosol-forming substrate.

Where an induction heating element is used, the induction heating element may be configured as an internal heating element as described herein or an external heater as described herein. If the induction heating element is configured as an internal heating element, the susceptor element is preferably configured as a fin or blade for penetrating the aerosol-generating article. If the induction heating element is configured as an external heating element, the susceptor element is preferably configured as a cylindrical susceptor which at least partially surrounds or forms a side wall of the heating chamber.

The heating element may heat the substrate portion of the aerosol-generating article by conduction. The heating element may be at least partially in contact with the substrate or carrier on which the substrate is deposited. Alternatively, heat from either the internal or external heating element may be conducted to the substrate by the thermally conductive element.

During operation, the aerosol-generating article may be completely contained within the aerosol-generating device. In this case, the user may puff on the mouthpiece of the aerosol-generating device. Alternatively, during operation, only the substrate portion of the aerosol-generating article may be included within the aerosol-generating device. In that case, the user can puff the aerosol-generating article directly.

The aerosol-generating device may comprise an electrical circuit. The electrical circuit may include a microprocessor, which may be a programmable microprocessor. The microprocessor may be part of the controller. The electrical circuit may include additional electronic components. The electrical circuit may be configured to regulate the power supply to the heating element. Power may be supplied to the heating element continuously after activation of the aerosol-generating device, or it may be supplied intermittently, such as with each puff. Power may be supplied to the heating element in the form of a current pulse. The electrical circuit may be configured to monitor the electrical resistance of the heating element and preferably to control the supply of power to the heating element according to the electrical resistance of the heating element.

The aerosol-generating device may comprise a power supply, typically a battery, within the main body of the aerosol-generating device. In one embodiment, the power supply is a lithium-ion battery. Alternatively, the power supply may be a nickel-hydrogen alloy battery, a nickel cadmium battery, or a lithium-based battery such as a lithium-cobalt, lithium-iron-phosphate, lithium titanate or lithium-polymer battery. Alternatively, the power supply may be another form of electrical charge storage device such as a capacitor. The power supply may require recharging and may have a capacity to store sufficient energy for one or more usage experiences; For example, the power supply may have sufficient capacity to continuously generate the aerosol for a period of about six minutes, or a period that is a multiple of six minutes. In another example, the power supply may have sufficient capacity to provide for individual activation of a predetermined number of puffs or heating elements.

Another aspect of the invention relates to a method of operating an aerosol-generating system as described herein, comprising:

A) a method step of inserting the aerosol-generating article into the heating chamber;

B) heating the aerosol-generating article through the heating element, thereby generating an aerosol and an aldehyde, wherein the aldehyde reacts with the nitrogen-containing nucleophilic compound to produce an aldehyde reducing aerosol.

During heating of the aerosol-generating article, an aerosol may be provided that is substantially free or completely free of aldehydes.

During heating of the aerosol-generating article, formaldehyde may be formed as an aldehyde, wherein the formaldehyde reacts with the nitrogen-containing nucleophilic compound, resulting in a formaldehyde reducing aerosol. Formaldehyde may be one primary aldehyde formed during the generation of an aerosol from an aerosol-forming substrate of the present invention.

An aerosol-generating article comprising an aerosol-forming substrate according to any embodiment of the present invention may comprise urea and/or lysine in the aerosol-forming substrate, preferably as a nitrogen-containing nucleophilic compound.

Another aspect of the invention also relates to the use of a nitrogen-containing nucleophilic compound for removing aldehydes from an aerosol formed by heating an aerosol-generating article as described herein.

During use of the nitrogen-containing nucleophilic compound, the aerosol may be heated to a temperature between 220°C and 400°C, preferably between 250°C and 290°C.

Features described with respect to one embodiment are equally applicable to other embodiments of the invention.

The invention will be further described by way of example only with reference to the accompanying drawings,
1 shows a column chart of formaldehyde content of different aerosol-generating articles containing tobacco as well as non-tobacco aerosol-forming substrates.
2 shows a column chart of the formaldehyde content of different aerosol-generating articles comprising different concentrations of urea.
3 shows a column chart of formaldehyde content of different aerosol-generating articles comprising tobacco or other non-tobacco aerosol-forming substrates with sucrose and lysine.
Figure 4 shows the release of the aerosol former glycerin during the course of 12 puffs taken by the user, depending on the amount of disaccharide sucrose in the aerosol-forming substrate.
5 shows a schematic diagram of an aerosol-generating system comprising an aerosol-generating device and an aerosol-generating article;

1 shows a column chart of the amount of formaldehyde detected in aerosols generated from various aerosol-generating articles having a heating element at a temperature of 350° C. FIG. The substrate portion containing the aerosol-forming substrate of the aerosol-generating article was heated by means of an inner blade. In general, formaldehyde in smoke can be detected by trapping the aerosol in a DNPH derivatization solution (2,4-dinitrophenylhydrazine) using a smoking machine. Up to 15 minutes after the end of the aerosol collection, pyridine is added to quench the derivatization reaction. A solution containing an internal standard is added to the stabilized aerosol extract and then analyzed using ultra-high performance liquid chromatography with MS-MS detection with an ESI (electrospray ionization) source in negative mode. In this figure and also in FIGS. 2 and 3 , the vertical axis represents the amount of formaldehyde detected in micrograms per aerosol-generating article. The column marked 10 shows that 3.7 micrograms of formaldehyde was detected in the aerosol of an aerosol-generating article comprising 75% by weight of the tobacco blend, 18% by weight of glycerin as an aerosol former and the balance as a binder. In contrast to tobacco-containing aerosol-generating articles, in the aerosol of an aerosol-generating article comprising 45 wt % cellulose, 30 wt % inositol, 20 wt % glycerin with the balance being a binder (column labeled 12), 15.4 micrograms Formaldehyde can be detected. Inositol acts as a plasticizer. The data show that up to 4 times more formaldehyde is released from a non-tobacco containing aerosol-forming substrate compared to a substrate containing tobacco. The columns labeled 14 and 16 are an aerosol-generating article comprising 45 wt % cellulose, 26.25 wt % inositol, 20 wt % glycerin and 3.75 wt % urea (column labeled 14) or 3.75 wt % lysine (column labeled 16) shows that formaldehyde may not be detectable in the aerosol of Thus, both urea and lysine can act as nitrogen-containing nucleophilic compounds that react with formaldehyde, thereby removing formaldehyde from the aerosol.

FIG. 2 shows a column chart of formaldehyde detected in aerosols generated from various aerosol-generating articles having a heating element at a temperature of 350° C. FIG. The column labeled 18 shows that in an aerosol formed from an aerosol-generating article comprising 75% by weight of a tobacco blend, 18% by weight of glycerin and the balance being a binder, 3.5 micrograms of formaldehyde can be detected. In the aerosol of an aerosol-generating article containing 56 wt% cellulose, 5 wt% carboxymethyl cellulose, 1 wt% urea, 3 wt% cellulose fibers and 35 wt% glycerin (column labeled 20), 2.11 micrograms of formaldehyde was found Thus, the amount of formaldehyde in the aerosol can be reduced by 39% if 1% by weight of urea is included as a formaldehyde scavenger. In the aerosol of an aerosol-generating article containing 49% by weight of cellulose, 8% by weight of carboxymethyl cellulose, 5% by weight of urea, 3% by weight of cellulose fibers and 35% by weight of glycerin (column labeled 22), formaldehyde was not detected.

3 shows a column chart of formaldehyde detected in aerosols of various aerosol-generating articles having different compositions. At 350° C. of a heating element comprising 75 wt. % tobacco blend with other ingredients as described above with respect to FIG. 2, 3.31 micrograms of formaldehyde can be detected in the aerosol-generating article (column labeled 24). An aerosol-generating article containing 58 wt % cellulose, 35 wt % glycerin, 4 wt % carboxymethyl cellulose and 3 wt % cellulose fibers yields 1.68 micrograms of formaldehyde (column labeled 26). In contrast, more formaldehyde, 2.61 micrograms, was detected in the aerosol of the aerosol-generating article, in which 10% by weight of cellulose was replaced by 10% by weight of sucrose (column labeled 28). This suggests that the presence of a disaccharide, sucrose, increases the amount of formaldehyde. The release of formaldehyde associated with disaccharides can be reliably reduced or suppressed by incorporating the nitrogen-containing nucleophilic compound of the present invention into an aerosol-forming substrate. The column labeled 30 indicates that formaldehyde in the aerosol of an aerosol-generating article comprising 56 wt% cellulose, 35 wt% glycerin, 2 wt% lysine as a nitrogen-containing nucleophilic compound, 4 wt% carboxymethyl cellulose and 3 wt% cellulose fibers shows that it may not be detected.

having a weight of 0.5 grams and having 42 wt% cellulose, 28 wt% sorbitol, 20 wt% glycerin, and 5 wt% ammonium phosphate, 5 wt% chitosan, 5 wt% lysine, 5 wt% urea or 5 wt% Similar results, although not shown in the figure, were achieved when an aerosol-forming article having an aerosol-forming substrate of polyethyleneimine, the remainder being cellulosic fibers and guar gum, was heated to 350° C. for 6 minutes. In all these cases, no formaldehyde could be detected by TG-GC-MS analysis.

4 is a graph, where the vertical axis shows the amount of glycerin per puff (micrograms/puff) detected by FT-IR and the horizontal axis shows the number of puffs. The graph shows the amount of glycerol detected in the aerosol during the course of 12 consecutive puffs at a temperature of 250° C. of the heating element. The graph denoted at 32 shows, for comparison, the amount of glycerin released from an aerosol-generating article containing 75 wt % tobacco, 18 wt % glycerin and the balance being a binder. The graph, denoted 34, shows that glycerin is released from an aerosol-generating article containing 58% by weight of cellulose, 35% by weight of glycerin, 4% by weight of carboxymethyl cellulose and 3% by weight of cellulosic fibers. A further graph shows the release of glycerin from an aerosol-generating article, wherein either 10% by weight of cellulose is replaced by 10% by weight of sucrose (labeled 36) or 20% by weight of cellulose is replaced by 20% by weight of sucrose (denoted as 38). graph) is replaced. Since the addition of sucrose retards the release of glycerin, it can be clearly seen that more glycerin is released at a later stage starting with puff number 7 or 8.

5 shows a schematic diagram of an aerosol-generating system comprising an aerosol-generating device 46 and an aerosol-generating article 40 . The aerosol-generating article 40 includes a substrate portion 42 and a connection portion 44 . The substrate portion 42 comprises the aerosol-forming substrate of the present invention and is located upstream in the direction of the aerosol-generating article. The downstream connection 44 may include a tubular hollow portion, such as a hollow acetate tube. The aerosol-generating article 40 can be inserted into the heating chamber 48 of the aerosol-generating device 46 in such a way that the substrate portion 42 is adjacent the heating element 50 of the heating chamber. Additional elements are present in the aerosol-generating device 46 , for example a circuit 52 , such as a microprocessor, and a power supply 54 , such as a battery, for example. The heating element as well as the power supply and circuit may be electrically connected via electrical connection 56 . During use of the aerosol-generating device, the user may inhale at the downstream end of the aerosol-generating article 40 , which is connected to a connection 44 not shown in FIG. 5 or to inhale the aerosol formed during heating of the substrate 42 or It may be an additional mouthpiece or filter. The aerosol may contain a reduced concentration of the aldehyde due to the presence of the nitrogen-containing nucleophilic compound in the aerosol-forming substrate of the substrate portion 42 .

Claims (15)

An aerosol-forming substrate comprising:
a) one or both of cellulose and cellulose derivatives;
b) an aerosol former;
c) 0% to 5% by weight, preferably 0% to 3% by weight, more preferably 0% to 1% by weight, most preferably 0% to 5% by weight, based on dry weight based on the total amount of the aerosol-forming substrate 0% to 0.5% by weight of tobacco,
d) a nitrogen-containing nucleophilic compound, and
e) a substrate comprising a disaccharide. The nitrogen-containing nucleophilic compound according to claim 1, wherein the nitrogen-containing nucleophilic compound is one or both of organic and inorganic compounds, preferably
- organic compounds with amino or amide groups, preferably amino acids, nitrogen-containing sugars and polysaccharides, or nitrogen-containing plastics;
- inorganic ammonium compounds,
- or a combination thereof
An aerosol-forming substrate selected from the group consisting of. According to claim 1 or 2, wherein the nitrogen-containing nucleophilic compound,
- an amino acid selected from the group consisting of lysine, glycine, cysteine, arginine, or homocysteine or combinations thereof,
- tripeptides including glutathione;
- urea or urea derivatives or combinations thereof;
- nitrogen-containing saccharides and polysaccharides selected from the group consisting of glucosamine, galactosamine, or chitosan, or combinations thereof,
- inorganic ammonium compounds, selected from ammonium phosphate and ammonium metal phosphate, in particular diammonium phosphate, triammonium phosphate, ammonium hydrogen phosphate, or ammonium dihydrogen phosphate, or ammonium alkaline earth metal phosphate or combinations thereof,
- a nitrogen-containing plastic selected from polyethylene-imine, polystyrene-acrylonitrile or polyacrylonitrilebutadiene-styrene or combinations thereof;
An aerosol-forming substrate selected from at least one of. 4. The aerosol-forming substrate according to any one of claims 1 to 3, comprising a disaccharide selected from sucrose, lactose, or maltose or combinations thereof, preferably sucrose. 5. The aerosol-forming substrate according to any one of claims 1 to 4, substantially free of tobacco, more preferably free of tobacco. 6. Aerosol according to any one of claims 1 to 5, wherein one or both of cellulose and cellulose derivatives are selected from cellulose, cellulose esters or cellulose ethers or combinations thereof, in particular cellulose acetate or carboxymethyl-cellulose. forming substrate. 7. The method of any one of claims 1 to 6, wherein the aerosol former is selected from polyhydric alcohols, esters of polyhydric alcohols, and aliphatic esters of mono-, di-, or polycarboxylic acids, or combinations thereof. aerosol-forming substrate. 8. The aerosol-forming substrate according to any one of claims 1 to 7, further comprising nicotine as component f). 9. The aerosol-forming substrate according to any one of the preceding claims, formed as a sheet, preferably a cast sheet. 10. The composition according to any one of claims 1 to 9, wherein one or both of the cellulose and the cellulose of component a), based on the total amount of the aerosol-forming substrate, from 15% to 85% by weight on a dry weight basis, preferably preferably present in an amount from 20% to 80% by weight, more preferably from 25% to 70% by weight. 11. An aerosol-generating article comprising a substrate portion containing the aerosol-forming substrate of any one of claims 1 to 10, preferably wherein the substrate portion within the article is in the form of a rod. An aerosol-generating system comprising an aerosol-generating device and the aerosol-generating article of claim 11 , wherein the aerosol-generating device comprises a heating element for receiving the aerosol-generating article and a heating chamber, wherein the heating element is preferably between 220° C. and An aerosol-generating system configured to heat the article to a temperature in the range of 400°C, preferably 250°C to 290°C. 13. A method of operating the aerosol-generating system of claim 12, said method comprising:
A) a method of inserting the aerosol-generating article into the heating chamber;
B) heating the aerosol-generating article via the heating element, thereby generating an aerosol and an aldehyde, wherein the aldehyde reacts with the nitrogen-containing nucleophilic compound to produce an aldehyde reducing aerosol. Use of a nitrogen-containing nucleophilic compound to provide an aldehyde reducing aerosol formed through heating the aerosol-generating article of claim 11 . 15. Use according to claim 14, wherein the aerosol-generating article is heated to a temperature between 220°C and 400°C, preferably between 250°C and 290°C.

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