TOBACCO SHEET FOR NON-COMBUSTION HEATING-TYPE FLAVOR INHALER, NON-COMBUSTION HEATING-TYPE FLAVOR INHALER, AND NON-COMBUSTION HEATING-TYPE FLAVOR INHALATION SYSTEM

Abstract

 A tobacco sheet for a heat-not-burn flavor inhaler, wherein the equilibrium moisture content is 14% by mass or less after 48 hours of conditioning at 22°C and 60% relative humidity.

Description

TECHNICAL FIELD

[0001] The present invention relates to a tobacco sheet for a heat-not-burn flavor inhaler, a heat-not-burn flavor inhaler, and a heat-not-burn flavor inhalation system.

BACKGROUND ART

[0002] The flavor of a combusted flavor inhaler (cigarette) is experienced by burning tobacco filler that contains leaf tobacco. Heat-not-burn flavor inhalers, with which flavor is experienced by heating, instead of burning, the flavor source, such as a tobacco sheet, have been proposed as an alternative to combusted flavor inhalers. The heating temperature of heat-not-burn flavor inhalers, which is about 400°C or below, for example, is lower than the burning temperature of combusted flavor inhalers. As the heating temperature of heat-not-burn flavor inhalers is thus lower, an aerosol-generating agent can be added to the flavor source in heat-not-burn flavor inhalers to enhance smoke volume The aerosol-generating agent is vaporized by being heated to generate an aerosol. The aerosol is supplied to the user along with the flavor component, such as a tobacco component, thus allowing the user to experience plenty of flavor.

[0003] Heat-not-burn flavor inhalers can comprise, for example: a tobacco-containing segment that is filled with a tobacco sheet, or the like; a cooling segment; and a filter segment. In heat-not-burn flavor inhalers, the axial length of the tobacco-containing segment relative to the heater is shorter than the axial length of the tobacco-containing segment of conventional combusted flavor inhalers. The shorter tobacco-containing segment compartment of heat-not-burn flavor inhalers is therefore filled with a large amount of tobacco sheet, for example, in order to ensure that enough aerosol is generated while heated. Tobacco sheets that are less bulky, specifically, that are high-density, are ordinarily used in heat-not-burn flavor inhalers in order to allow the shorter segments to be filled with large amounts of tobacco sheets, for example. Bulkiness refers to a value indicating the volume of a predetermined mass of shredded tobacco sheet when compressed at a constant pressure for a given period of time. PTL 1 and 2, for example, disclose tobacco sheets that are used in heat-not-burn flavor inhalers.

CITATION LIST

PATENT LITERATURE

[0004] 

[PTL 1] JP 5969923 B2

[PTL 2] WO 2020/058814 A1

SUMMARY OF INVENTION

TECHNICAL PROBLEM

[0005] However, when the heating method or heater thermal capacity and aerosol generation are taken in to consideration, the inventors discovered that, depending on the heating method or heater thermal capacity, the tobacco sheet used to fill the tobacco-containing segment does not adequately contribute to the generation of aerosol because of the increase in the total heat capacity of the tobacco-containing segment. This compromises delivery, particularly in the early stages of flavor inhalation. Consideration was given to reducing the total heat capacity of the tobacco-containing segment in order to solve this problem.

[0006] To reduce the total heat capacity of the tobacco-containing segment, the inventors studied (1) reducing the specific heat of the tobacco raw material included in tobacco sheets and (2) using a more bulky (low density) tobacco sheet. The inventors then entertained the notion of reducing the total heat capacity of the tobacco-containing segment by adjusting the moisture content of the tobacco sheet to within an appropriate range.

[0007] An object of the present invention is to provide: a tobacco sheet for a heat-not-burn flavor inhaler that will ensure good delivery in the early stages of flavor inhalation; a heat-not-burn flavor inhaler comprising said tobacco sheet; and a heat-not-burn flavor inhalation system.

SOLUTION TO PROBLEM

[0008] The above problem is solved as follows.

Aspect 1

[0009] A tobacco sheet for a heat-not-burn flavor inhaler, wherein the equilibrium moisture content is 14% by mass or less after 48 hours of conditioning at 22°C and 60% relative humidity.

Aspect 2

[0010] The sheet according to aspect 1, which is a rolled sheet or cast sheet.

Aspect 3

[0011] The sheet according to aspect 1 or 2, wherein the sheet comprises a powder of at least one tobacco raw material selected from the group consisting of leaf tobacco, midrib, and stem waste.

Aspect 4

[0012] The sheet according to aspect 3, wherein the powder is contained in a proportion of 45 to 95% by mass per 100% by mass of the tobacco sheet.

Aspect 5

[0013] The sheet according to any of aspects 1 through 4, wherein the tobacco sheet further comprises an aerosol-generating agent.

Aspect 6

[0014] The sheet according to aspect 5, wherein the aerosol-generating agent is at least one selected from the group consisting of glycerol, propylene glycol, and 1, 3-butanediol.

Aspect 7

[0015] The sheet according to aspect 5 or 6, wherein the aerosol-generating agent is contained in a proportion of 4 to 50% by mass per 100% by mass of the tobacco sheet.

Aspect 8

[0016] The sheet according to any of aspects 1 through 7, wherein the tobacco sheet further comprises a binder.

Aspect 9

[0017] The sheet according to aspect 8, wherein the binder is at least one selected from the group consisting of polysaccharides, proteins, and synthetic polymers.

Aspect 10

[0018] The sheet according to aspect 8 or 9, wherein the binder is contained in a proportion of 0.1 to 15% by mass per 100% by mass of the tobacco sheet.

Aspect 11

[0019] The sheet according to any of aspects 3 through 10, comprising a tobacco powder in which the cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, of the tobacco raw material powder is 200 µm or more.

Aspect 12

[0020] A heat-not-burn flavor inhaler that is equipped with a tobacco-containing segment comprising the sheet according to any of aspects 1 through 11.

Aspect 13

[0021] A heat-not-burn flavor inhalation system, comprising:

the heat-not-burn flavor inhaler according to aspect 12; and

a heating device for heating the tobacco-containing segment.

Aspect 14

[0022] A method for producing the sheet according to aspect 11, comprising:

(1) a step of preparing a composition for a sheet comprising tobacco powder S, the D90 of which is less than 200 µm, and producing a sheet S;

(2) a step of preparing a plurality of tobacco powders T1 through Tn (where n is the number 2 or greater) that have different D90 values, wherein the D90 is equal to or greater than 200 µm, preparing compositions for sheets comprising the tobacco powders, and producing sheets T1 through Tn;

(3) a step of determining the equilibrium moisture content, after 48 hours of conditioning at 22°C and 60% relative humidity, of the sheet S or chopped pieces of the sheet S and the sheets T1 through Tn or chopped pieces thereof;

(4) a step of determining a tobacco powder A, which is a sheet-forming tobacco powder having a moisture reduction rate, defined below, of -3% or less, selected from tobacco powders T1 through Tn;

Wt: equilibrium moisture content of sheets T1 through Tn or chopped pieces thereof

Ws: equilibrium moisture content of the sheet S or chopped pieces thereof; and

(5) a step of producing a sheet from the tobacco powder A.

ADVANTAGEOUS EFFECTS OF INVENTION

[0023] A tobacco sheet for a heat-not-burn flavor inhaler that will ensure good delivery in the early stages of flavor inhalation; a heat-not-burn flavor inhaler comprising said tobacco sheet; and a heat-not-burn flavor inhalation system can be provided.

BRIEF DESCRIPTION OF DRAWINGS

[0024] 

Fig. 1 is a cross sectional diagram showing an example of a heat-not-burn flavor inhaler according to the present embodiment.

Fig. 2 is a cross sectional diagram showing an example of a heat-not-burn flavor inhalation system according to the present embodiment in (a) a state before the heat-not-burn flavor inhaler is inserted into the heating device, and (b) a state where the heat-not-burn flavor inhaler has been inserted into the heating device to be heated.

DESCRIPTION OF EMBODIMENTS

Tobacco sheet for a heat-not-burn flavor inhaler

[0025] The tobacco sheet for a heat-not-burn flavor inhaler (also referred to below as "tobacco sheet") in one embodiment has an equilibrium moisture content of 14% by mass or less after 48 hours of conditioning at 22°C and 60% relative humidity. An equilibrium moisture content within this range will allow the available heat quantity to be efficiently used to generate the aerosol, thus allowing good delivery to be achieved in the early stages of flavor inhalation. In this respect, the equilibrium moisture content is preferably 7.5 to 10% by weight. The equilibrium moisture content can be determined using a heat-drying moisture analyzer (such as the heat-drying moisture analyzer MX-50, by A&D Company, Ltd.).

(Tobacco powder)

[0026] The tobacco sheet according to the present embodiment preferably comprises a tobacco raw material, and more preferably comprises a powder of said raw material (also referred to below as "tobacco powder"). The cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractrometry, of the tobacco powder is preferably 200 µm or more. In such cases, there are large voids between the particles of the tobacco powder in the tobacco sheet, and these voids presumably help to increase the bulkiness of the tobacco sheet. The large voids between the particles of the tobacco powder also make it easier for moisture to be released, allowing the heat capacity of the heated portion to be reduced. The tobacco sheet according to the present embodiment even more preferably further comprises an aerosol-generating agent or a binder; ensuring that these are blended in proportions within a predetermined range will further improve the bulkiness of the tobacco sheet.

[0027] Examples of tobacco powder contained in the tobacco sheet according to the present embodiment include leaf tobacco, midrib, and stem waste. One type may be used, or two or more types may be used in combination. These can be cut to a predetermined size for use in the form of tobacco powder. In terms of the size of the tobacco powder, the cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, is equal to or greater than 200 µm, preferably equal to or greater than 350 µm, and even more preferably equal to or greater than 500 µm. The upper limit of the range of the D90 is not particularly limited, but can be, for example, equal to or less than 2000 µm.

[0028] In terms of the size of the tobacco powder, the cumulative 50% particle size (D50) in a volume-based particle size distribution, as determined by dry laser diffractometry, is also equal to or greater than 40 µm, preferably equal to or greater than 100 µm, and even more preferably equal to or greater than 200 µm, in the interests of further increasing the bulkiness of the tobacco sheet. The upper limit of the range of the D50 is not particularly limited, but can be, for example, equal to or less than 1000 µm. In the present embodiment, the D90 and D50 can be determined by dry laser diffractometry using, for example, the Mastersizer (tradename, by Spectris Inc., Malvern Panalytical).

[0029] The tobacco raw material (preferably tobacco powder) is contained in a proportion of 45 to 95% by mass per 100% by mass of the tobacco sheet. Ensuring that the proportion of the tobacco raw material is 45% by mass or more will allow enough tobacco flavor to be generated while heated. Also, ensuring that the proportion of the tobacco raw material is no more than 95% by mass will ensure that enough of the aerosol-generating agent or binder is included. The proportion of the tobacco raw material is more preferably 50 to 93% by mass, even more preferably 55 to 90% by mass, and in particular preferably 60 to 88% by mass.

(Aerosol-generating agent)

[0030] The tobacco sheet according to the present embodiment preferably further comprises an aerosol-generating agent in the interests of greater smoke volume while heated. Examples of aerosol-generating agents include glycerol, propylene glycol, and 1,3-butanediol. One may be used, or two or more may be used in combination.

[0031] When an aerosol-generating agent is to be included in the tobacco sheet, the proportion of the aerosol-generating agent is preferably 4 to 50% by mass per 100% by mass of the tobacco sheet. Ensuring that the proportion of the aerosol-generating agent is 4% by mass or more will allow enough aerosol in terms of quantity to be generated while heated. Also, ensuring that the proportion of the aerosol-generating agent is no more than 50% by mass will allow enough aerosol in terms of heat capacity to be generated while heated. The proportion of the aerosol-generating agent is more preferably 6 to 40% by mass, even more preferably 8 to 30% by mass, and in particular preferably 10 to 20% by mass.

(Binder)

[0032] The tobacco sheet according to the present embodiment preferably further comprises a binder in the interests of shape retention. Examples of binders include polysaccharides, proteins, and synthetic polymer. One may be used, or two or more may be used in combination. Examples of polysaccharides include cellulose derivatives and naturally derived polysaccharides.

[0033] Examples of cellulose derivatives include cellulose ethers such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxymethyl ethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, benzyl cellulose, trityl cellulose, cyanoethyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, and aminoethyl cellulose; inorganic acid esters such as cellulose acetate, cellulose formate, cellulose propionate, cellulose butyrate, cellulose benzoate, cellulose phthalate, and tosyl cellulose; and inorganic acid esters such as cellulose nitrate, cellulose sulfate, cellulose phosphate, and cellulose xanthate.

[0034] Examples of naturally derived polysaccharides include plant-derived polysaccharides such as guar gum, tara gum, roasted bean gum, tamarind seed gum, pectin, gum arabic, tragacanth gum, gum karaya, gum ghatti, arabinogalactan, linseed gum, cassia gum, psyllium seed gum, and Artemisia sphaerocephala seed gum; algae-derived polysaccharides such as carageenan, agar, alginic acid, propylene glycol alginate, furcelleran, and Colpomenia sinuosa extract; microbially-derived polysaccharides such as xanthan gum, gellan gum, curdlan, pullulan, agrobacterium succinoglycan, welan gum, macrophomopsis gum, and rhamsan gum; shellfish-derived polysaccharides such as chitin, chitosan, and glucosamine; and starches such as starch, sodium carboxymethyl starch, pregelatinized starch, and dextrin.

[0035] Examples of proteins include cereal proteins such as wheat gluten and rye gluten. Examples of synthetic polymers include polyphosphoric acid, sodium polyacrylate, and polyvinylpyrrolidone.

[0036] When a binder is to be included in the tobacco sheet, the proportion of the binder is preferably 0.1 to 15% by mass per 100% by mass of the tobacco sheet. Using the binder in a proportion of 0.1% by mass or more will allow the mixture of raw materials to be formed into a sheet. Also, using the binder in a proportion of no more than 15% by mass will allow enough other ingredients to be used in order to ensure functions that are required of the tobacco-containing segment of the heat-not-burn flavor inhaler. The proportion of the binder is more preferably 0.2 to 13% by mass, even more preferably 0.5 to 12% by mass, and in particular preferably 1 to 10% by mass.

(Reinforcing agent)

[0037] The tobacco sheet according to the present embodiment can further comprise a reinforcing agent in the interests of further improvement in physical properties. Examples of reinforcing agents include fibrous substances such as fibrous pulp, insoluble fiber, and fibrous synthetic cellulose, and liquid substances having a film-forming surface-coating function, such as pectin aqueous suspension. One may be used, or two or more may be used in combination.

[0038] When a reinforcing agent is to be included in the tobacco sheet, the proportion of the reinforcing agent is preferably 4 to 60% by mass per 100% by mass of the tobacco sheet. Keeping the proportion within this range will allow enough other ingredients to be used in order to ensure functions that are required of the tobacco-containing segment of the heat-not-burn flavor inhaler. The proportion of the reinforcing agent is more preferably 4.5 to 55% by mass, and even more preferably 5 to 50% by mass.

(Aids)

[0039] The tobacco sheet according to this embodiment can further comprise an aid in the interests of quality assurance. Examples of aids include sugar alcohols such as sorbitol, erythritol, xylitol, maltitol, lactitol, mannitol, and reduced maltose syrup. One may be used, or two or more may be used in combination.

[0040] When an aid is to be included in the tobacco sheet, the proportion of the aid is preferably 1 to 15% by mass per 100% by mass of the tobacco sheet. Keeping the proportion within this range will allow enough other ingredients to be used in order to ensure functions that are required of the tobacco-containing segment of the heat-not-burn flavor inhaler. The proportion of the aid is more preferably 2 to 12% by mass, and even more preferably 3 to 10% by mass.

(Other Ingredients)

[0041] The tobacco sheet according to the present embodiment may comprise flavoring, such as fragrances and flavors, colorants, preservatives, and diluents such as inorganic substances in addition to the tobacco raw material, aerosol-generating agent, binder, reinforcing agent, and aids noted above.

(Bulkiness)

[0042] The bulkiness of the tobacco sheet according to the present embodiment is preferably 190 cc/100 g or higher. A bulkiness of 190 cc/100 g or more will allow the total heat capacity of the tobacco-containing segment of the heat-not-burn flavor inhaler to be sufficiently reduced, thus allowing the tobacco sheet used to fill the tobacco-containing segment to contribute more to the generation of the aerosol. The bulkiness is more preferably 210 cc/100g or more, and even more preferably 230 cc/100 g. The upper limit of the range of the bulkiness is not particularly limited, but can be, for example, 800 cc/100 g or less. Bulkiness is a value determined using DD-60A (tradename, by Borgwaldt) after a tobacco sheet that has been cut to a size of 0.8 mm × 9.5 mm has been stored for 48 hours in a conditioning chamber set to 22°C and 60% humidity. The value is determined by introducing 15 g of the cut tobacco sheet into a cylindrical container having an inside diameter of 60 mm, and determining the volume compression for 30 seconds under a load of 3 kg.

(Tobacco sheet structure)

[0043] In the present embodiment, "tobacco sheet" refers to an object in which the ingredients making up the tobacco sheet, such as tobacco powder, are formed into a sheet shape. As used here, "sheet" means a shape having a pair of substantially parallel main faces and side faces. The length and width of the tobacco sheet are not particularly restricted, and can be adjusted as befits the way said sheet is used to fill the segment. The thickness of the tobacco sheet is not particularly limited, but is preferably 100 to 1000 µm, and more preferably 150 to 600 µm, in the interests of the balance between heat transfer efficiency and strength.

(Method for Producing Tobacco Sheet)

[0044] The tobacco sheet according to the present embodiment may be produced by a known method such as rolling or casting methods. Details on various types of tobacco sheets produced by such methods are disclosed in "Dictionary of Tobacco, Tobacco Academic Studies Center, March 31, 2009". Examples of methods utilizing tobacco powder as a tobacco raw material are described below as preferred aspectts.

Rolling method

[0045] A method comprising the following steps can be given as an example of a method for producing a tobacco sheet by means of a rolling method (rolled sheet):

(1) a step in which water, tobacco powder, an aerosol-generating agent, a binder, and a reinforcing agent are mixed to obtain a mixture;

(2) a step in which the mixture is rolled between calendering rollers;

(3) a step in which the product formed by means of rolling is dried in a dryer.

When a tobacco sheet is produced by this method, the surface of the calendering rollers may be heated or cooled, and the rotating speed of the calendering rollers may be adjusted, depending on the intended purpose. The gap between the calendering rollers may also be adjusted. One or more calendering rollers can be used to obtain a tobacco sheet of the desired basis weight.

Casting method

[0046] A method comprising the following steps can be given as an example of a method for producing a tobacco sheet by means of a casting method (cast sheet):

(1) a step in which water, tobacco powder, an aerosol-generating agent, a binder, and pulp are mixed to obtain a mixture; and

(2) a step in which the mixture is thinly spread (cast) and dried to form a tobacco sheet.

When a tobacco sheet is produced by this method, a step may be added, wherein a slurry that has been obtained by mixing water, tobacco powder, an aerosol-generating agent, a binder, and pulp is exposed to ultraviolet or X-ray radiation to remove some components such as nitrosamine.

(Moisture reduction rate)

[0047] The tobacco sheet according to the present embodiment preferably has a moisture reduction rate of -3% by mass or less. The moisture reduction rate is an indicator of how low the equilibrium moisture content of the target sheet is compared with the equilibrium moisture content of a standard sheet. As noted above, the equilibrium moisture content is the moisture content after 48 hours of conditioning at 22°C and 60% relative humidity. The lower the moisture reduction rate, the lower the equilibrium moisture content of the target sheet. Specifically, the moisture reduction rate is defined as (Wt-Ws)/Ws, where Wt is the equilibrium moisture content of a sheet obtained from the tobacco powder T according to the present embodiment, and Ws is the equilibrium moisture content of a standard sheet obtained from tobacco powder S having a D90 of <200 µm. A tobacco sheet satisfying this moisture reduction rate will have a low moisture content, thus allowing the heat capacity of the heated portion to be reduced. The upper limit of the moisture reduction rate is preferably equal to or less than -4% by mass, or equal to or less than -5% mass. The lower limit of the moisture reduction rate is preferably equal to or greater than -20% by mass.

[0048] Specifically, the tobacco sheet according to the present embodiment is preferably produced by a method comprising the following steps:

(1) a step of preparing a composition for a sheet comprising tobacco powder S, the D90 of which is less than 200 µm, and producing a sheet S;

(2) a step of preparing a plurality of tobacco powders T1 through Tn (where n is the number 2 or greater) that have different D90 values, wherein the D90 is equal to or greater than 200 µm, preparing compositions for sheets comprising the tobacco powders, and producing sheets T1 through Tn;

(3) a step of determining the equilibrium moisture content, after 48 hours of conditioning at 22°C and 60% relative humidity, of the sheet S or chopped pieces of the sheet S and the sheets T1 through Tn or chopped pieces thereof;

(4) a step of determining sheet-forming tobacco powder A having a moisture reduction rate, defined below, of -3% or less, where, tobacco powder A is selected among tobacco powders T1 through Tn:

Wt: equilibrium moisture content of sheets T1 through Tn or chopped pieces thereof

Ws: equilibrium moisture content of the sheet S or chopped pieces thereof, and

(5) a step of producing a sheet from the tobacco powder A.

[0049] Methods for producing the sheet in step (1), for example, have already been noted above. However, the sheet production method should standardized through all steps. For example, if a cast sheet is selected in step (1), cast sheets should also be prepared in subsequent steps. The D90 of the standard tobacco powder S is not limited, provided that is is less than 200 µm, but is preferably between 80 to 90 µm. The objects used to determine Ws and Wt should have the same shape. For example, when Ws is the equilibrium moisture content of a sheet, Wt should also be the equilibrium moisture content of a sheet.

Heat-not-burn flavor inhaler

[0050] The heat-not-burn flavor inhaler according to the present embodiment comprises a tobacco-containing segment that includes, for example, the tobacco sheet according to the present embodiment. The heat-not-burn flavor inhaler according to the present embodiment comprises a tobacco-containing segment that is filled with, for example, the highly bulky tobacco sheet according to the present embodiment, thus allowing the total heat capacity of the tobacco-containing segment to be sufficiently reduced, so that the tobacco sheet used to fill the tobacco-containing segment can contribute more to aerosol generation.

[0051] Fig. 1 shows an example of the heat-not-burn flavor inhaler according to the present embodiment. The heat-not-burn flavor inhaler 1 shown in Fig. 1 comprises: a tobacco-containing segment 2 filled with the tobacco sheets, etc., according to the present embodiment; a cylindrical cooling segment 3 having a perforation 8 in the perimeter thereof; a center hole segment 4; and a filter segment 5. The heat-not-burn flavor inhaler according to the present embodiment may have other segments in addition to the tobacco-containing segment, the cooling segment, the center hole segment and the filter segment.

[0052] The axial length of the heat-not-burn flavor inhaler according to the present embodiment is not particularly limited, but is preferably 40 mm to 90 mm, more preferably 50 mm to 75 mm, and even more preferably 50 mm to 60 mm. The circumferential length of the heat-not-burn flavor inhaler is preferably 16 mm to 25 mm, more preferably 20 mm to 24 mm, and even more preferably 21 mm to 23 mm. In an exemplary aspect which may be cited, the length of the tobacco-containing segment is 20 mm, the length of the cooling segment is 20 mm, the length of the center hole segment is 8 mm, and the length of the filter segment is 7 mm. The length of the filter segment can be selected within the range of 4 mm to 10 mm. The length can also be selected so that the ventilation resistance of the filter segment at such times is at least 15 mmH₂O per segment and no more than 60 mmH₂O per segment. The length of these individual segments can be modified, as appropriate, depending on manufacturability and required quality, for example. The heat-not-burn flavor inhaler can furthermore still function even when the filter segment is disposed downstream of the cooling segment without the use of a center hole segment.

(Tobacco-containing segment)

[0053] The tobacco-containing segment 2 is formed by packing the tobacco sheet, etc. according to the present embodiment, inside rolling paper (also referred to below as a wrapper). The method for packing the tobacco sheet, etc., inside the rolling paper (also referred to below as a wrapper) is not particularly limited but, for example, the tobacco sheet, etc., may be enclosed inside a wrapper, or the tobacco sheet, etc., may be packed inside a cylindrical wrapper. Tobacco sheets that are longitudinally shaped so as to be rectangular may be packed in such a way as to be randomly oriented in any direction in the wrapper, or may be packed while oriented in the axial direction, or a direction perpendicular to said axial direction, of the tobacco-containing segment 2.

(Cooling Segment)

[0054] In one embodiment, as shown in Fig. 1, the cooling segment 3 may be composed of a cylindrical member 7. The cylindrical member 7 may be a paper tube obtained by processing cardboard into a cylindrical shape, for example.

[0055] The cylindrical member 7 and a mouthpiece lining paper 12 (described below) are provided with a perforation 8 that penetrates both. The perforation 8 allows external air to be introduced into the cooling segment 3 during inhalation. As a result, the aerosol vaporized component that is generated when the tobacco-containing segment 2 is heated will come into contact with the external air and cool off, and will thus become liquefied to form an aerosol. The diameter of the perforation 8 (the length across the perforation) is not particularly limited, but may be 0.5 mm to 1.5 mm, for example. The number of perforations is not particularly limited, and may be one or more. Multiple perforations 8 may be provided on the circumference of the cooling segment 3, for example.

[0056] The amount of external air introduced from the perforation 8 is preferably 85% by volume or less, and more preferably 80% by volume or less, with respect to the overall volume of gas drawn in by the user. A proportion of up to 85% by volume of external air will make it possible to adequately control the loss of flavor that results from dilution by external air. This is also referred to as the ventilation ratio. The lower limit of the ventilation ratio range is preferably 55% by volume or greater, and more preferably 60% by volume or greater, in the interests of cooling properties.

[0057] The cooling segment may also comprise a sheet of a suitable constituent material that has been wrinkled, pleated, gathered, or folded. Cross-sectional profiles of such elements may show randomly oriented channels. The cooling segment may also comprise a bundle of longitudinally extending tubes. Such a cooling segment may be formed, for example, by wrapping a pleated, gathered, or folded sheet material in rolling paper.

[0058] The axial length of the cooling segment may be 7 mm to 28 mm, for example, and may be 18 mm, for example. The cooling segment can also be substantially circular in terms of the axial cross-sectional shape, and the diameter can be 5 mm to 10 mm, for example, and can be 7 mm for example.

(Center hole segment)

[0059] The center hole segment may be composed of a filling layer having one or more hollow portions, and an inner plug wrapper (inside rolling paper) that covers the filling layer. As shown in Fig. 1, for example, the center hole segment 4 may be composed of a second filling layer 9 having a hollow portion, and a second inner plug wrapper 10 that covers the second filling layer 9. The center hole segment 4 has the function of increasing the strength of the mouthpiece segment 6. The second filling layer 9 may be formed, for example, as a rod having an inner diameter of φ1.0 mm-φ5.0 mm packed with a high density of cellulose acetate fibers, a plasticizer comprising triacetin being added thereto in an amount of 6 mass%-20 mass%, in relation to the mass of cellulose acetate, and the plasticizer being cured. The second filling layer 9 has a high fiber packing density, so the air and aerosol flow only through the hollow portion during inhalation, with virtually none flowing through the second filling layer 9. The second filling layer 9 inside the center hole segment 4 is a fiber-filled layer, and the user will therefore will feel little discomfort when touching the outside during use. The shape of the center hole segment 4 may also be retained by means of thermoforming, without the second inner plug wrapper 10 being provided.

(Filter segment)

[0060] The configuration of the filter segment 5 is not particularly limited, but it may be composed of one or more filling layers. The outside of the filling layer may be wrapped with one or more rolling papers. The ventilation resistance per segment of the filter segment 5 may be modified, as appropriate, depending on, for example, the amount and material, for example, of the filler with which the filter segment 5 is filled. For example, when the filler is cellulose acetate fibers, the ventilation resistance can be increased by increasing the amount of cellulose acetate fibers with which the filter segment 5 is filled. When the filler is cellulose acetate fibers, the packing density of cellulose acetate fibers may be 0.13 to 0.18 g/cm³. The ventilation resistance is the value determined using a ventilation resistance analyzer (trade name: SODIMAX, by SODIM).

[0061] The circumferential length of the filter segment 5 is not particularly limited, but it is preferably 16 to 25 mm, more preferably 20 to 24 mm, and even more preferably 21 to 23 mm. The filter segment 5 can have an axial length of 4 to 10 mm, which can be selected so as to result in a ventilation resistance of 15 to 60 mmH₂O per segment. The axial length of the filter segment 5 is preferably 5 to 9 mm, and more preferably 6 to 8 mm. The cross-sectional shape of the filter segment 5 is not particularly limited but may be circular, elliptical, or polygonal, for example. Fragrance-containing destructible capsules, fragrance beads, and fragrances can also be directly added to the filter segment 5.

[0062] As shown in Fig. 1, the center hole segment 4 and the filter segment 5 can be connected by means of an outer plug wrapper (outside rolling paper) 11. The outer plug wrapper 11 may be cylindrical paper, for example. The tobacco-containing segment 2, cooling segment 3, and the connected center hole segment 4 and filter segment 5 can be connected by means of mouthpiece lining paper 12. These connections may be formed, for example, by coating the inside surface of the mouthpiece lining paper 12 with a glue such as a vinyl acetate-based glue, and inserting the three segments noted above, which are then wrapped with the mouthpiece lining paper 20. These segments may also be connected by multiple separate connections with multiple lining papers.

(Heat-not-burn flavor inhalation system)

[0063] The heat-not-burn flavor inhalation system according to the present embodiment comprises: the heat-not-burn flavor inhaler according to the present embodiment; and a heating device for heating the tobacco-containing segment of said heat-not-burn flavor inhaler. The heat-not-burn flavor inhaler system according to the present embodiment may have a configuration other than the heat-not-burn flavor inhaler according to the present embodiment and the heating device.

[0064] Fig. 2 shows an example of the heat-not-burn flavor inhalation system according to this embodiment. The heat-not-burn flavor inhalation system shown in Fig. 2 comprises: the heat-not-burn flavor inhaler 1 according to the present embodiment; and a heating device 13 for heating, from the outside, the tobacco-containing segment of the heat-not-burn flavor inhaler 1.

[0065] Fig. 2(a) shows the heat-not-burn flavor inhaler 1 before it is inserted into the heating device 13, and Fig. 2(b) shows the heat-not-burn flavor inhaler 1 after it has been inserted into the heating device 13 to be heated. The heating device 13 shown in Fig. 2 comprises: a body 14, a heater 15, a metal tube 16, a battery unit 17, and a control unit 18. The body 14 has a cylindrical recess 19, and the heater 15 and metal tube 16 are disposed on the inside side face of the recess 19 at positions facing the tobacco-containing segment of the heat-not-burn flavor inhaler 1 which is inserted into the recess 19. The heater 15 may be a heater employing electrical resistance, and electrical power is supplied by the battery unit 17 in accordance with a command from the control unit 18, which controls the temperature, such that heating is provided by the heater 15. The heat emitted from the heater 15 is transferred through the highly thermally conductive metal tube 16 to the tobacco-containing segment 4 the heat-not-burn flavor inhaler 1.

[0066] As Fig. 2(b) is a schematic diagram, there is a gap between the outer circumference of the heat-not-burn flavor inhaler 1 and the inner circumference of the metal tube 16, but for the purposes of efficient heat transfer, there should actually preferably be no gap between the outer circumference of the heat-not-burn flavor inhaler 1 and the inner circumference of the metal tube 16. Also, the tobacco-containing segment of the heat-not-burn flavor inhaler 1 is externally heated by the heating device 13 but may be internally heated.

[0067] The heating temperature of the heating device is not particularly limited, but is preferably 400°C or below, more preferably 150 to 400°C, and even more preferably 200 to 350°C. The heating temperature refers to the temperature of the heater of the heating device.

EXAMPLES

[0068] Specific examples of this embodiment will be described below, but the present invention is not limited by these examples.

EXAMPLE 1

[0069] Tobacco lamina (leaf tobacco) was dry ground using a Hosokawa Micron ACM machine to obtain tobacco powder. Analysis of the tobacco powder by dry laser diffractrometry using a Mastersizer (tradename, by Spectris Inc., Malvern Panalytical) revealed that the cumulative 50% particle size (D50) and cumulative 90% particle size (D90) in a volume-based particle size distribution were 57 µm and 216 µm, respectively.

[0070] The tobacco powder was used to produce tobacco sheets via rolling. Specifically, 87 parts by mass of the tobacco powder, 12 parts by mass of glycerol (as the aerosol-generating agent), and 1 part by mass of carboxymethyl cellulose (as the binder) were mixed, and were kneaded using an extruder. The kneaded mixture was molded into the form of sheets through two pairs of metal rolls, and the sheets were dried in an 80°C circulating hot air oven to obtain tobacco sheets. The tobacco sheets were cut to a size of 0.8 mm × 9.5 mm using a shredder.

[0071] The bulkiness of the cut tobacco sheets was determined. Specifically, the cut tobacco sheets were allowed to stand for 48 hours in a conditioning chamber at 22°C and 60% relative humidity, and the bulkiness was then determined using a DD-60A (tradename, by Borgwaldt). This was determined by introducing 15 g of the cut tobacco sheet into a cylindrical container having an inside diameter of 60 mm, and determining the volume compression for 30 seconds under a load of 3 kg. The results are shown in Table 1. In Table 1, bulkiness is shown as the rate of increase (%) in bulkiness relative to a standard value based on the value of the bulkiness in Comparative Example 1 described below.

EXAMPLE 2

[0072] Tobacco sheets were produced, and assessed, in the same manner as in Example 1, except for the use of tobacco powder in which the cumulative 50% particle size (D50) and cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, were 121 µm and 389 µm, respectively. The results are shown in Table 1.

EXAMPLE 3

[0073] Tobacco sheets were produced, and assessed, in the same manner as in Example 1, except for the use of tobacco powder in which the cumulative 50% particle size (D50) and cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, were 225 µm and 623 µm, respectively. The results are shown in Table 1.

COMPARATIVE EXAMPLE 1

[0074] Tobacco sheets were produced, and assessed, in the same manner as in Example 1, except for the use of tobacco powder in which the cumulative 50% particle size (D50) and cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, were 32 µm and 84 µm, respectively. The results are shown in Table 1.

[0075] Table 1 shows that the tobacco sheets of Examples 1 through 3 (tobacco sheets according to the present embodiment) had improved bulkiness compared with that of the tobacco sheet of Comparative Example 1, in which the D90, as determined by dry laser diffractometry, was less than 200 µm. In Examples 1 through 3, the tobacco sheets were produced by a rolling method, but bulkiness was also improved when tobacco sheets were similarly produced by a casting method.

EXAMPLES A AND COMPARATIVE EXAMPLE A

[0076] 

(1) Tobacco lamina (leaf tobacco) was dry ground using a Hosokawa micron ACM machine to obtain tobacco powder. A tobacco powder particle size where the cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractrometry using a Mastersizer (tradename, by Spectris Inc., Malvern Panalytical), was adopted.

(2) The above tobacco powder was used to produce tobacco sheets by the rolling method. Specifically,
the tobacco powder, glycerol (as the aerosol-generating agent), and carboxymethyl cellulose (as the binder) were mixed in the proportions shown in Table 2 below, and were kneaded using an extruder. The kneaded mixture was molded into the form of sheets through a pair of metal rolls, and the sheets were dried in an 80°C circulating hot air oven to obtain tobacco sheets. The tobacco sheets were cut to a size of 0.8 mm × 9.5 mm using a shredder.

(3) The moisture content of the cut tobacco sheets was determined. Specifically, the cut tobacco sheets were allowed to stand for 48 hours in a conditioning chamber at 22°C and 60% relative humidity, and the moisture content, specifically, the equilibrium moisture content, was then determined using the heat-drying moisture analyzer MX-50 by A&D Company, Ltd.

(4) The moisture reduction rate was determined based on the following formula, where Ws is the equilibrium moisture content Ws of the sheets obtained in Comparative Example A1, and Wt is the equilibrium moisture content of the sheets obtained Examples A.

[0077] The results are presented in Table 2.

[Table 2]

[0078] 

[0079] Aspects of implementation are listed below.

Aspect 1

[0080] A tobacco sheet for a heat-not-burn flavor inhaler, wherein the equilibrium moisture content is 14% by mass or less after 48 hours of conditioning at 22°C and 60% relative humidity.

Aspect 2

[0081] The sheet according to aspect 1, which is a rolled sheet or cast sheet.

Aspect 3

[0082] The sheet according to aspect 1 or 2, wherein the sheet comprises a powder of at least one tobacco raw material selected from the group consisting of leaf tobacco, midrib, and stem waste.

Aspect 4

[0083] The sheet according to aspect 3, wherein the powder is contained in a proportion of 45 to 95% by mass per 100% by mass of the tobacco sheet.

Aspect 5

[0084] The sheet according to any of aspects 1 through 4, wherein the tobacco sheet further comprises an aerosol-generating agent.

Aspect 6

[0085] The sheet according to aspect 5, wherein the aerosol-generating agent is at least one selected from the group consisting of glycerol, propylene glycol, and 1, 3-butanediol.

Aspect 7

[0086] The sheet according to aspect 5 or 6, wherein the aerosol-generating agent is contained in a proportion of 4 to 50% by mass per 100% by mass of the tobacco sheet.

Aspect 8

[0087] The sheet according to any of aspects 1 through 7, wherein the tobacco sheet further comprises a binder.

Aspect 9

[0088] The sheet according to aspect 8, wherein the binder is at least one selected from the group consisting of polysaccharides, proteins, and synthetic polymers.

Aspect 10

[0089] The sheet according to aspect 8 or 9, wherein the binder is contained in a proportion of 0.1 to 15% by mass per 100% by mass of the tobacco sheet.

Aspect 11

[0090] The sheet according to any of aspects 3 through 10, comprising a tobacco powder in which the cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, of the tobacco raw material powder is 200 µm or more.

Aspect 12

[0091] A heat-not-burn flavor inhaler that is equipped with a tobacco-containing segment comprising the sheet according to any of aspects 1 through 11.

Aspect 13

[0092] A heat-not-burn flavor inhalation system, comprising:

the heat-not-burn flavor inhaler according to aspect 12; and

a heating device for heating the tobacco-containing segment.

Aspect 14

[0093] A method for producing the sheet according to aspect 11, comprising:

(1) a step of preparing a composition for a sheet comprising tobacco powder S, the D90 of which is less than 200 µm, and producing a sheet S;

(2) a step of preparing a plurality of tobacco powders T1 through Tn (where n is the number 2 or greater) that have different D90 values, wherein the D90 is equal to or greater than 200 µm, preparing compositions for sheets comprising the tobacco powders, and producing sheets T1 through Tn;

(3) a step of determining the equilibrium moisture content, after 48 hours of conditioning at 22°C and 60% relative humidity, of the sheet S or chopped pieces of the sheet S and the sheets T1 through Tn or chopped pieces thereof;

(4) a step of determining a tobacco powder A, which is a sheet-forming tobacco powder having a moisture reduction rate, defined below, of -3% or less, selected from tobacco powders T1 through Tn;

Wt: equilibrium moisture content of sheets T1 through Tn or chopped pieces thereof

Ws: equilibrium moisture content of the sheet S or chopped pieces thereof, and

(5) a step of producing a sheet from the tobacco powder A.

REFERENCE SIGNS LIST

[0094] 

1

Heat-not-burn flavor inhaler

2

Tobacco-containing segment

3

Cooling segment

4

Center hole segment

5

Filter segment

6

Mouthpiece segment

7

Cylindrical member

8

Perforation

9

Second filling layer

10

Second inner plug wrapper

11

Outer plug wrapper

12

Mouthpiece lining paper

13

Heating device

14

Body

15

Heater

16

Metal tube

17

Battery unit

18

Control unit

19

Recess

Claims

1. A tobacco sheet for a heat-not-burn flavor inhaler, wherein the equilibrium moisture content is 14% by mass or less after 48 hours of conditioning at 22°C and 60% relative humidity.

2. The sheet according to claim 1, which is a rolled sheet or cast sheet.

3. The sheet according to claim 1 or 2, wherein the sheet comprises a powder of at least one tobacco raw material selected from the group consisting of leaf tobacco, midrib, and stem waste.

4. The sheet according to claim 3, wherein the powder is contained in a proportion of 45 to 95% by mass per 100% by mass of the tobacco sheet.

5. The sheet according to any of claims 1 through 4, wherein the tobacco sheet further comprises an aerosol-generating agent.

6. The sheet according to claim 5, wherein the aerosol-generating agent is at least one selected from the group consisting of glycerol, propylene glycol, and 1, 3-butanediol.

7. The sheet according to claim 5 or 6, wherein the aerosol-generating agent is contained in a proportion of 4 to 50% by mass per 100% by mass of the tobacco sheet.

8. The sheet according to any of claims 1 through 7, wherein the tobacco sheet further comprises a binder.

9. The sheet according to claim 8, wherein the binder is at least one selected from the group consisting of polysaccharides, proteins, and synthetic polymers.

10. The sheet according to claim 8 or 9, wherein the binder is contained in a proportion of 0.1 to 15% by mass per 100% by mass of the tobacco sheet.

11. The sheet according to any of claims 3 through 10, wherein the cumulative 90% particle size (D90) in a volume-based particle size distribution, as determined by dry laser diffractometry, of the tobacco raw material powder is 200 µm or more.

12. A heat-not-burn flavor inhaler that is equipped with a tobacco-containing segment comprising the sheet according to any of claims 1 through 11.

13. A heat-not-burn flavor inhalation system, comprising:

the heat-not-burn flavor inhaler according to claim 12; and

a heating device for heating the tobacco-containing segment.

14. A method for producing the sheet according to claim 11, comprising:

(1) a step of preparing a composition for a sheet comprising tobacco powder S, the D90 of which is less than 200 µm, and producing a sheet S;

(2) a step of preparing a plurality of tobacco powders T1 through Tn (where n is the number 2 or greater) that have different D90 values, wherein the D90 is equal to or greater than 200 µm, preparing compositions for sheets comprising the tobacco powders, and producing sheets T1 through Tn;

(3) a step of determining the equilibrium moisture content, after 48 hours of conditioning at 22°C and 60% relative humidity, of the sheet S or chopped pieces of the sheet S and the sheets T1 through Tn or shredded pieces thereof;

(4) a step of determining a tobacco powder A, which is a sheet-forming tobacco powder having a moisture reduction rate, defined below, of -3% or less, selected from tobacco powders T1 through Tn;

Wt: equilibrium moisture content of sheets T1 through Tn or chopped pieces thereof

Ws: equilibrium moisture content of the sheet S or chopped pieces thereof; and

(5) a step of producing a sheet from the tobacco powder A.

Drawing