Aerosol generating sheet

Abstract

The present invention provides a method for producing an aerosol generating sheet containing a tobacco extract E and another component B, the production method comprising: (1) a step of preparing a mixture containing the tobacco extract E and the other component B, the mixture satisfying the following formula: Liquid-to-solid ratio = weight of moisture in mixture / weight of components other than moisture in mixture ≥ 3; and (2) a step of obtaining a sheet from the mixture.

Description

Aerosol-generating sheet

[0001] The present invention relates to an aerosol-generating sheet.

[0002] The aerosol-generating sheet serves as a flavor source for smoking articles. Patent Documents 1 and 2 disclose aerosol-generating sheets that use tobacco extract as a tobacco-derived material.

[0003] Patent No. 6695359 Patent No. 5248486

[0004] As disclosed in Patent Documents 1 and 2, when a sheet is produced using a tobacco extract, the sheet composition needs to be concentrated. If a sheet could be produced without concentrating the sheet composition, the production process could be made more efficient. In view of these circumstances, an object of the present invention is to provide an efficient method for producing an aerosol-generating sheet.

[0005] The inventors solved the above problem by setting the liquid-solid ratio, defined as "weight of water in the mixture / weight of components other than water in the mixture," to a specific value or higher. That is, the above problem is solved by the following invention. Aspect 1: A method for producing an aerosol-generating sheet containing tobacco extract E and other component B, comprising: (1) preparing a mixture containing tobacco extract E and other component B, which satisfies the following relationship: liquid-solid ratio = weight of water in the mixture / weight of components other than water in the mixture ≥ 3; and (2) obtaining a sheet from the mixture. Aspect 2 The step (1) comprises: (1-1) subjecting a tobacco raw material to a preliminary extraction with water to obtain a tobacco extract L containing a tobacco extract E and water, and determining an extraction rate a defined by the following formula (1): Extraction rate a = Ed (E dry matter weight) / Td (tobacco raw material dry matter weight) (1); (1-2) determining X, relating to the weight of water to be used in a new extraction performed using the same method as in step (1-1), based on the following formula (I): Liquid-solid ratio = (X / a) × t + (Bw / Bd) × (1 - t) (I) (where, liquid-solid ratio ≧ 3 X = Ew (weight of water in tobacco extract L) / Td (tobacco raw material dry matter weight) Bw: total weight of water in all components B Bd: total weight of dry matter in all components B t = tobacco extract usage rate = Ed / (Ed + Bd); (1-3) subjecting the tobacco raw material to extraction using water in an amount that satisfies X to obtain a tobacco extract; (1-4) mixing the tobacco extract obtained in (1-3) with the other components to prepare a mixture satisfying formula (I).Aspect 3 The step (1) comprises: (1-1) subjecting the tobacco raw material to a preliminary extraction with a mixed solvent containing water and alcohol to obtain a tobacco extract E and a tobacco extract liquid L' containing water and alcohol, and determining an extraction rate a' defined by the following formula (1'): Extraction rate a' = Ed (E dry matter weight) / Td (tobacco raw material dry matter weight) (1'); (1-2) determining X, relating to the weight of water to be used in a new extraction performed using the same method as in step (1-1), based on the following formula (I'): Liquid-solid ratio = (X / a') x t + (Bw / Bd) x (1 - t) (I') (where, liquid-solid ratio ≥ 3 X = Ew (weight of water in tobacco extract liquid L') / Td (tobacco raw material dry matter weight) Bw: total weight of water in all components B Bd: total weight of dry matter in all components B t = tobacco extract usage rate = Ed / (Ed + Bd) A manufacturing method according to Aspect 1, comprising the steps of: (1-3) determining the amount of the mixed solvent to be used in a new extraction from the weight ratio X, and extracting the tobacco material with the mixed solvent in that amount to obtain a tobacco extract; and (1-4) mixing the tobacco extract obtained in (1-3) with the other components to prepare a mixture satisfying formula (I'). Aspect 4 A manufacturing method according to any one of Aspects 1 to 3, wherein the aerosol-generating sheet contains 15 to 50% by weight of the tobacco extract, on a dry basis. Aspect 5 A manufacturing method according to any one of Aspects 1 to 4, wherein the other component B comprises an aerosol source, and wherein the aerosol-generating sheet contains 10 to 60% by weight of the aerosol source, on a dry basis. Aspect 6 A manufacturing method according to any one of Aspects 1 to 5, wherein the other components include non-wood fiber, wood fiber, or a binder. Aspect 7 A manufacturing method according to Aspect 6, wherein the non-wood fiber is dietary fiber. Aspect 8 A manufacturing method according to Aspect 7, wherein the non-wood fiber is citrus fiber. Aspect 9 Aspect 10: The method of any one of aspects 6 to 9, wherein the binder is carboxyalkyl cellulose or guar gum. Aspect 11: The method of any one of aspects 6 to 9, wherein the content of wood fibers is less than the content of non-wood fibers.

[0006] The present invention provides an efficient method for producing an aerosol-generating sheet.

[0007] In this disclosure, "X to Y" includes the end values ​​X and Y. Dry weight is the weight excluding the weight of water.

[0008] 1. Manufacturing Method In one embodiment, a method for manufacturing an aerosol-generating sheet containing tobacco extract E and other component B comprises the steps of: (1) preparing a mixture containing tobacco extract E and other component B and having a specific liquid-to-solid ratio; and (2) obtaining a sheet from the mixture.

[0009] (1) Step (1): Mixture Preparation Step In this step, a mixture containing tobacco extract E and other component B is prepared, which satisfies the following relationship: liquid-solid ratio = weight of water in the mixture / weight of components other than water in the mixture ≥ 3. If the liquid-solid ratio is less than 3, it becomes difficult to prepare a sheet. On the other hand, if the upper limit is too high, the amount of active ingredients in the resulting sheet decreases. From this perspective, the upper limit of the liquid-solid ratio is preferably 8 or less, more preferably 5 or less. A mixture with a liquid-solid ratio within this range can be subjected to the sheet manufacturing process without concentration. This prevents the reduction of flavor components. Although the "components other than water in the mixture" may include substances that are liquid at room temperature, for convenience in this disclosure, the liquid-solid ratio will be defined as above.

[0010] The type of sheet obtained varies depending on the amounts of the components contained in the mixture. For example, in a type in which the dry matter weight of tobacco extract E in the mixture is greater than the dry matter weight of the aerosol source (hereinafter also referred to as a "tobacco-rich type"), the liquid-solid ratio is preferably 3 to 5. In this case, the ratio of the dry matter weight of the tobacco extract E to the dry matter weight of the mixture is preferably 15 to 50 wt%. Furthermore, in a type in which the dry matter weight of the aerosol source in the mixture is greater than the dry matter weight of tobacco extract E (hereinafter also referred to as an "aerosol-source-rich type"), the liquid-solid ratio is preferably 3 to 5. In this case, the ratio of the dry matter weight of the aerosol source to the dry matter weight of the mixture is preferably 40 to 60 wt%.

[0011] 1) Tobacco Extract Tobacco extract E is a substance or mixture that exhibits a flavor extracted from tobacco. Tobacco extract can be prepared by known methods. The medium used for extraction can be water or a hydrophilic organic solvent such as alcohol. In one embodiment, the medium is water (this embodiment is also referred to as "water extraction"), and in another embodiment, the medium is a mixed solvent of water and alcohol (this embodiment is also referred to as "solvent extraction"). Examples of alcohol include polyhydric alcohols such as propylene glycol and glycerin, and monoalcohols such as ethanol. The alcohol is preferably an aerosol source, as described below.

[0012] Examples of extraction methods include: 1) a method in which tobacco raw materials are subjected to extraction using a medium to obtain a tobacco extract; 2) a method in which a medium is added to tobacco raw materials, heating the materials, and collecting the generated vapor; and 3) a method in which the medium is heated to generate vapor and passed through the tobacco raw materials, and the vapor is collected after passing through the tobacco raw materials. In method 1), aqueous extraction is preferred from the viewpoint of workability. Furthermore, in methods 2) and 3), solvent extraction is preferred from the viewpoint of work efficiency. An acid or alkali can also be used for extraction as needed. The liquid obtained by extraction, containing tobacco extract E and the medium, is referred to as tobacco extract liquid L.

[0013] As the tobacco raw material, for example, raw materials of the Nicotiana genus such as Nicotiana tabacum and Nicotiana rustica can be used. As Nicotiana tabacum, for example, varieties such as Burley or flue-cured varieties can be used. In addition to these, Oriental varieties and native Burley varieties of the Nicotiana genus may also be used.

[0014] The tobacco raw material may be shredded or powdered tobacco raw material (hereinafter also referred to as "raw material pieces"). In such cases, the particle size of the raw material pieces is preferably 0.5 to 1.18 mm. Such raw material pieces can be obtained, for example, by sieving in accordance with JIS Z 8815 using a stainless steel sieve in accordance with JIS Z 8801. For example, 1) using a stainless steel sieve with 1.18 mm meshes, the raw material pieces are sieved by a dry mechanical shaking method for 20 minutes to obtain raw material pieces that pass through the stainless steel sieve with 1.18 mm meshes. 2) Subsequently, using a stainless steel sieve with 0.50 mm meshes, the raw material pieces are sieved by a dry mechanical shaking method for 20 minutes to remove the raw material pieces that pass through the stainless steel sieve with 0.50 mm meshes. In this way, raw material pieces can be prepared that pass through a stainless steel sieve (mesh opening = 1.18 mm) that defines the upper limit, but do not pass through a stainless steel sieve (mesh opening = 0.50 mm) that defines the lower limit.

[0015] In one embodiment, a tobacco raw material is treated with an alkali. Flavor components are generated through the treatment and collected to prepare a tobacco extract liquid L containing tobacco extract E and water. In this process, it is preferable to extract the flavor components as a gas from the alkali-treated tobacco raw material and introduce the gas into water to convert the flavor components into a liquid.

[0016] The alkaline substance is preferably an alkaline liquid such as an aqueous potassium carbonate solution. In this case, the alkaline substance is supplied until the pH of the tobacco raw material falls within a specific range. The pH is preferably 8.0 or higher, more preferably 8.9 to 9.7. The pH of the tobacco raw material is the pH of water when the tobacco raw material is mixed with 10 times the amount of water.

[0017] The moisture content of the tobacco raw material is not limited, but from the viewpoint of efficiently extracting flavor components, the moisture content is preferably approximately 5 to 30% by weight. The moisture content of the tobacco raw material is measured by a known method; for example, a 1-g sample is taken, heated at 105°C, and the moisture content is determined as the weight loss when heated until the weight change rate is 1 mg / min or less. For this measurement, for example, a halogen heating moisture meter (such as the MB45 manufactured by Ohaus Co., Ltd.) can be used.

[0018] If the amount of tobacco extract E is too small, the smoking taste will be unsatisfactory, while if it is too large, the strength of the sheet may decrease. From this perspective, the lower limit of the ratio of tobacco extract E dry matter weight / mixture dry matter weight is preferably 10 wt % or more, 15 wt % or more, or 20 wt % or more. The upper limit is preferably 60 wt % or less, 50 wt % or less, or 40 wt % or less. In particular, in the case of a tobacco-rich type, the ratio is preferably 20 to 50 wt %. In the case of an aerosol source-rich type, the ratio is preferably 10 to 40 wt %. In this embodiment, the amount of each component in the mixture on a dry basis (dry matter weight of each component / dry matter weight of the mixture) is equal to the amount of each component in the sheet on a dry basis (dry matter weight of each component / dry matter weight of the sheet).

[0019] 2) Other Components B 2-2) Aerosol Source Examples of aerosol sources include polyhydric alcohols such as glycerin or propylene glycol. The moisture content in the aerosol source is measured by known methods, for example, the same method as that used to measure the moisture content in tobacco raw materials. If the amount of aerosol source is too small, the amount of smoke produced during smoking is insufficient. If the amount is too large, the sheet becomes difficult to handle. From this perspective, the lower limit of the ratio of the dry matter weight of the aerosol source to the dry matter weight of the mixture is preferably 5% by weight or more, 10% by weight or more, 20% by weight or more, or 40% by weight or more. The upper limit is preferably 70% by weight or less, 60% by weight or less, 50% by weight or less, or 40% by weight or less. In particular, for aerosol-rich types, the ratio is preferably 40 to 60% by weight. Furthermore, for tobacco-rich types, the ratio is preferably 10 to 40% by weight, more preferably 20 to 40% by weight.

[0020] 2-3) Non-wood Fibers Non-wood fibers are fibers not derived from wood, and are preferably fibers other than tobacco fibers. Tobacco fibers are unlikely to impart strength to the sheet and may impart an unpleasant flavor. Dietary fibers are preferred as non-wood fibers. Dietary fibers are food components that are not digested by human digestive enzymes, and are more preferably insoluble dietary fibers that do not dissolve in water. Dietary fibers may be porous, i.e., spongy. Porous fibers can increase the surface area of ​​the smoking article sheet and improve the thermal conductivity of the sheet. From the standpoint of availability, the fiber is preferably citrus fiber. Citrus fiber is a fiber made primarily from the albedo of citrus fruits. Dietary fiber may also be short fibers or columnar particles with a small aspect ratio. Citrus fiber is particularly preferred because it can impart strength to the sheet with a small amount. The moisture content of non-wood fibers is measured by known methods, for example, the same method as that used for the moisture content of tobacco raw materials. In one embodiment, the ratio of non-wood fiber dry matter weight / mixture dry matter weight is 10-40% by weight or 10-30% by weight.

[0021] 2-4) Wood Fiber Wood fiber can be used as another component. Examples of wood fiber include softwood pulp, Vitacel FL400, and Vitacel L600 / 30 (all manufactured by J. Rettenmaier & Sohne GmbH). The moisture content of the wood fiber is measured, and the amount of wood fiber blended is determined so as to satisfy the above-mentioned relationship. The moisture content of the wood fiber is measured by a known method, for example, the same method as that for the moisture content of tobacco raw materials. In one embodiment, the ratio of wood fiber dry weight to mixture dry weight is 1 to 10% by weight. When wood fiber and non-wood fiber are present, the content of wood fiber is preferably less than the content of non-wood fiber.

[0022] 2-5) Binder A binder can be used as another component. Examples of binders include carboxyalkyl cellulose and guar gum. The moisture content in the binder is measured, and the amount of binder blended is determined so as to satisfy the above relationship. The moisture content in the binder is measured by a known method, and can be measured, for example, by the same method as the moisture content of the tobacco raw material. In one embodiment, the ratio of the binder dry matter weight to the mixture dry matter weight is 1 to 10% by weight.

[0023] 2-6) Flavorings Examples of flavorings include menthol, but are not limited to this and the flavorings described below can also be used. The amount of flavoring may be a known amount. These flavorings may be used alone or in combination of two or more.

[0024] Preferred fragrances include acetanisole, acetophenone, acetylpyrazine, 2-acetylthiazole, alfalfa extract, amyl alcohol, amyl butyrate, trans-anethole, star anise oil, apple juice, Peru balsam oil, beeswax absolute, benzaldehyde, benzoin resinoid, benzyl alcohol, benzyl benzoate, benzyl phenylacetate, benzyl propionate, 2,3-butanedione, 2-butanol, butyl butyrate, butyric acid, caramel, cardamom oil, carob absolute, β-carotene, carrot juice, L-carnitine, benzoin ... benzoate, benzyl phenylacetate, benzyl propionate, 2,3-butanedione, 2-butanol, butyl butyrate, butyric acid, caramel, cardamom oil, carob absolute, β-carotene, carrot juice, L-carnitine, benzoin, benzyl benzoate, benzyl phenylacetate, benzyl propionate, 2,3-butanedione, 2-butanol, butyl butyrate, butyric acid, caramel, cardamom oil, carob absolute, β-carotene, carrot juice, L-carnitine, benzoin, benzyl benzoate, benzyl phenylacetate, benzyl propionate, 2,3-butanedione, 2-butanol, butyl butyrate, butyric acid, caramel, cardamom oil, carob absolute, β-carotene, carrot juice, L-carnitine, Rubone, β-caryophyllene, cassia bark oil, cedarwood oil, celery seed oil, chamomile oil, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, cinnamyl cinnamate, citronella oil, DL-citronellol, clary sage extract, cocoa, coffee, konjac oil, coriander oil, cuminaldehyde, davana oil, δ-decalactone, γ-decalactone, decanoic acid, dill herb oil, 3,4-dimethyl-1,2-cyclopentanedione, 4,5-dimethyl-3-hydroxy-2,5-dihydrofuran-2-one, 3,7-dimethyl 1-octenoic acid, 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, ethyl 2-methylbutyrate, ethyl acetate, ethyl butyrate, ethyl hexanoate, ethyl isovalerate, ethyl lactate, ethyl laurate, ethyl levulinate, ethyl maltol, ethyl octanoate, ethyl oleate, ethyl palmitate, ethyl phenylacetate, ethyl propionate, ethyl stearate, ethyl valerate, ethyl vanillin, ethyl vanillin glucoside, 2-ethyl-3,(5 or 6)-dimethylpyrazine, 5-ethyl-3-hydroxybenzoate Cis-4-methyl-2(5H)-furanone, 2-ethyl-3-methylpyrazine, eucalyptol, fenugreek absolute, gene absolute, gentian root infusion, geraniol, geranyl acetate, grape juice, guaiacol, guava extract, gamma-heptalactone, gamma-hexalactone, hexanoic acid, cis-3-hexen-1-ol, hexyl acetate, hexyl alcohol, phenylhexyl acetate, honey, 4-hydroxy-3-pentenoic acid lactone, 4-hydroxy-4-(3-hydroxy-1-butenyl)-3,5,5-trimethyl-2-cyclohexen-1-one, 4-(para-hydroxyphenyl)-2-butanone, sodium 4-hydroxyundecanoate, inmortell absolute, beta-ionone, isoamyl acetate, isoamyl butyrate, isoamyl phenylacetate, isobutyl acetate, isobutyl phenylacetate, jasmine absolute, cola nut tincture, labdanum oil, lemon terpeneless oil, licorice extract, linalool, linalyl acetate, lovage root oil, maltol, maple Syrup, menthol, menthone, L-menthyl acetate, para-methoxybenzaldehyde, methyl 2-pyrrolyl ketone, methyl anthranilate, methyl phenylacetate, methyl salicylate, 4'-methylacetophenone, methylcyclopentenolone, 3-methylvaleric acid, mimosa absolute, honey, myristic acid, nerol, nerolidol, gamma-nonalactone, nutmeg oil, delta-octalactone, octanal, octanoic acid, orange flower oil, orange oil, orris root oil, palmitic acid, omega-pentane Intadecalactone, peppermint oil, petitgrain Paraguay oil, phenethyl alcohol, phenethyl phenylacetate, phenylacetic acid, piperonal, plum extract, propenylguaethol, propyl acetate, 3-propylidenephthalide, prune juice, pyruvic acid, raisin extract, rose oil, rum, sage oil, sandalwood oil, spearmint oil, styrax absolute, marigold oil, tea distillate, alpha-terpineol, terpinyl acetate, 5,6,7, 8-Tetrahydroquinoxaline, 1,5,5,9-tetramethyl-13-oxacyclo(8.3.0.0(4.9))tridecane, 2,3,5,6-tetramethylpyrazine, thyme oil, tomato extract, 2-tridecanone, triethyl citrate, 4-(2,6,6-trimethyl-1-cyclohexenyl)2-buten-4-one, 2,6,6-trimethyl-2-cyclohexene-1,4-dione, 4-(2,6,6-trimethyl-1,3-cyclohexadienyl)2-buten-4-one, 2,3,5-trimethylpyrazine, γ-undecalactone, γ-valerolactone, vanilla extract, vanillin, veratraldehyde, violet leaf absolute, N-ethyl-p-menthane-3-carboxamide (WS-3), ethyl-2-(p-menthane-3-carboxamide) acetate (WS-5).

[0025] 3) Preferred Aspects [In the Case of Water Extraction] Step (1) preferably comprises the following steps (1-1) to (1-4). <Step (1-1)> In this step, the tobacco raw material is subjected to preliminary extraction with water, and an extraction rate a defined by the following formula (1) is determined. Extraction rate a = Ed (dry weight of tobacco extract E) / Td (dry weight of tobacco raw material) (1) The dry weight is the weight excluding water. Therefore, Ed (dry weight of tobacco extract E) is the dry weight of the tobacco extract liquid L obtained by extraction, i.e., the weight obtained by subtracting the weight of water from the tobacco extract liquid L.

[0026] The extraction can be carried out by a known method. The extraction temperature is not limited, but is preferably 60 to 100° C., and more preferably 70 to 90° C. from the viewpoint of smoking taste. The extraction time is preferably 20 to 40 minutes.

[0027] <Step (1-2)> In this step, a factor X relating to the weight of water to be used in a new extraction is determined based on formula (I). The liquid-solid ratio is determined so as to satisfy the above range.

[0028] Liquid-solid ratio = (X / a) x t + (Bw / Bd) x (1-t) (I)

[0029] X is defined as Ew (weight of water in the tobacco extract L) / Td (weight of the dry matter of the tobacco raw material). In other words, X is the weight ratio of water used for extraction to the weight of the dry matter of the tobacco raw material.

[0030] Bw is the total weight of water in all components B in the mixture obtained in steps 1-4. All components B refer to all components other than the tobacco extract, including, for example, the aerosol source and fibers. Bd is the total dry weight of all components B in the mixture obtained in steps 1-4. Bw and Bd can be determined by analyzing each component using a known method.

[0031] t is the proportion of tobacco extract used, and is defined as Ed / (Ed+Bd). That is, t is the "dry weight of tobacco extract E / dry weight of the mixture" in the mixture obtained in step 1-4.

[0032] Formula (I) can be derived as follows: Liquid-solid ratio (R) = weight of water in the mixture / weight of components other than water in the mixture. Therefore, it can be transformed as follows:

[0033]

[0034] <Step (1-3)> In this step, a tobacco extract is obtained by extracting the tobacco raw material with water in an amount that satisfies the above-mentioned X. The extraction conditions are the same as those for the preliminary extraction.

[0035] <Step (1-4)> In this step, the tobacco extract obtained in step (1-3) is mixed with other components to prepare a mixture that satisfies formula (I), that is, has a desired liquid-solid ratio R.

[0036] [In the case of solvent extraction] Step (1) preferably comprises the following steps (1-1') to (1-4'). <Step (1-1')> In this step, the tobacco raw material is subjected to pre-extraction with the mixed solvent, and an extraction rate a' defined by the following formula (1') is determined. Extraction rate a' = Ed (dry weight of tobacco extract E) / Td (dry weight of tobacco raw material) (1') Ed (dry weight of tobacco extract E) is the weight of the tobacco extract liquid L' obtained by extraction minus the weights of water and alcohol. Extraction can be carried out as described for water extraction.

[0037] <Step (1-2')> In this step, a factor X relating to the weight of water in the mixed solvent to be used for new extraction using the mixed solvent is determined based on the formula (I').

[0038] Liquid-solid ratio = (X / a') x t + (Bw / Bd) x (1-t) (I')

[0039] X is defined as Ew (weight of water in the tobacco extract L') / Td (weight of the dry matter of the tobacco raw material). In other words, X is the weight ratio of water used in solvent extraction to the weight of the dry matter of the tobacco raw material.

[0040] Bw is the total weight of water in all components B in the mixture obtained in step 1-4'. Bd is the total dry weight of all components B in the mixture obtained in step 1-4'. Bd includes the dry weight of alcohol used in solvent extraction.

[0041] t is the ratio of tobacco extract used in the solvent extraction, and is defined as Ed / (Ed+Bd). Similar to the above formula (I), formula (I') can be derived as follows.

[0042]

[0043] <Step (1-3')> In this step, the composition and amount of the mixed solvent to be used for a new extraction are first determined from X. For example, if the weight ratio of water to alcohol in the mixed solvent used in the preliminary extraction is 1:z, a mixed solvent is prepared by mixing X water with X x z alcohol. Then, extraction is carried out using this mixed solvent to obtain a tobacco extract. The extraction conditions are the same as those for the preliminary extraction.

[0044] <Step (1-4')> This step can be carried out in the same manner as step (1-4).

[0045] (2) Step (2): Sheet Preparation Step In this step, a sheet is obtained from the mixture prepared in step (1). Sheets can be produced by known methods, but the above-described effects are even more pronounced when using a casting method. Generally, in a casting method, the tobacco extract in the mixture must be concentrated to increase the solids concentration in the mixture. However, in this embodiment, a mixture with an appropriate liquid-to-solid ratio is prepared, allowing casting to be performed without concentration. Concentration typically involves heating and decompression. During this process, problems such as the removal of some of the flavor components in the extract or the deterioration of the flavor components can occur. Depending on the flavor components, the equipment may become contaminated, and the deterioration of the flavor components can lead to a deterioration in the smoking experience. While it is possible to recover the removed flavor components, this would be a cumbersome process. These problems can be avoided in this embodiment.

[0046] When a sheet is obtained without concentration, for example, the mixture is cast onto a substrate without going through the concentration step to form a wet sheet. The wet sheet is then dried to obtain a tobacco sheet. In particular, it is preferable to mix the tobacco extract obtained in step (1-3) with the other components to prepare a mixture satisfying formula (I), and obtain a sheet (cast sheet) from the mixture. The drying temperature is preferably 50 to 100°C. A tobacco sheet obtained by the casting method is also called a "cast sheet."

[0047] The mixture used in the casting method can be prepared by known methods, but is preferably prepared by a method comprising the following steps: Step 1: Mixing tobacco extract with an aerosol source such as glycerin (if water is also added, water is also mixed at this time); Step 2: Mixing a binder with the mixture and continuing mixing until the binder is uniformly mixed; Step 3: Mixing other solid components with the mixture obtained in Step 2. If solid components including the binder are mixed together first, the binder will form lumps, and this state will be difficult to resolve. In this method, the binder and aerosol source are mixed first, so the binder is less likely to form lumps. "Lumping" refers to a state in which the components are not dispersed or dissolved but exist as clumps.

[0048] 2. Aerosol-Generating Sheet The aerosol-generating sheet obtained by the above-described manufacturing method is useful as a filler for smoking articles. Examples of smoking articles include combustion-type smoking articles and non-combustion-heat-type smoking articles. In particular, the aerosol-generating sheet obtained by the above-described method can be made into a tobacco-rich type or an aerosol source-rich type, as described above, thereby meeting the diverse needs of consumers.

[0049] Embodiments are described below. Aspect 1: A method for producing an aerosol-generating sheet containing tobacco extract E and other component B, comprising: (1) preparing a mixture containing the tobacco extract E and other component B, the mixture satisfying the following relationship: liquid-solid ratio = weight of water in the mixture / weight of components other than water in the mixture ≥ 3; and (2) obtaining a sheet from the mixture. Aspect 2 The step (1) comprises: (1-1) subjecting a tobacco raw material to a preliminary extraction with water to obtain a tobacco extract L containing a tobacco extract E and water, and determining an extraction rate a defined by the following formula (1): Extraction rate a = Ed (E dry matter weight) / Td (tobacco raw material dry matter weight) (1); (1-2) determining X, relating to the weight of water to be used in a new extraction performed using the same method as in step (1-1), based on the following formula (I): Liquid-solid ratio = (X / a) × t + (Bw / Bd) × (1 - t) (I) (where, liquid-solid ratio ≧ 3 X = Ew (weight of water in tobacco extract L) / Td (tobacco raw material dry matter weight) Bw: total weight of water in all components B Bd: total weight of dry matter in all components B t = tobacco extract usage rate = Ed / (Ed + Bd); (1-3) subjecting the tobacco raw material to extraction using water in an amount that satisfies X to obtain a tobacco extract; (1-4) mixing the tobacco extract obtained in (1-3) with the other components to prepare a mixture satisfying formula (I).Aspect 3 The step (1) comprises: (1-1) subjecting the tobacco raw material to a preliminary extraction with a mixed solvent containing water and alcohol to obtain a tobacco extract E and a tobacco extract liquid L' containing water and alcohol, and determining an extraction rate a' defined by the following formula (1'): Extraction rate a' = Ed (E dry matter weight) / Td (tobacco raw material dry matter weight) (1'); (1-2) determining X, relating to the weight of water to be used in a new extraction performed using the same method as in step (1-1), based on the following formula (I'): Liquid-solid ratio = (X / a') x t + (Bw / Bd) x (1 - t) (I') (where, liquid-solid ratio ≥ 3 X = Ew (weight of water in tobacco extract liquid L') / Td (tobacco raw material dry matter weight) Bw: total weight of water in all components B Bd: total weight of dry matter in all components B t = tobacco extract usage rate = Ed / (Ed + Bd) A manufacturing method according to Aspect 1, comprising the steps of: (1-3) determining the amount of the mixed solvent to be used in a new extraction from the weight ratio X, and extracting the tobacco material with the mixed solvent in that amount to obtain a tobacco extract; and (1-4) mixing the tobacco extract obtained in (1-3) with the other components to prepare a mixture satisfying formula (I'). Aspect 4 A manufacturing method according to any one of Aspects 1 to 3, wherein the aerosol-generating sheet contains 15 to 50% by weight of the tobacco extract, on a dry basis. Aspect 5 A manufacturing method according to any one of Aspects 1 to 4, wherein the other component B comprises an aerosol source, and wherein the aerosol-generating sheet contains 10 to 60% by weight of the aerosol source, on a dry basis. Aspect 6 A manufacturing method according to any one of Aspects 1 to 5, wherein the other components include non-wood fiber, wood fiber, or a binder. Aspect 7 A manufacturing method according to Aspect 6, wherein the non-wood fiber is dietary fiber. Aspect 8 A manufacturing method according to Aspect 7, wherein the non-wood fiber is citrus fiber. Aspect 9 Aspect 10: The method of any one of aspects 6 to 9, wherein the binder is carboxyalkyl cellulose or guar gum. Aspect 11: The method of any one of aspects 6 to 9, wherein the content of wood fibers is less than the content of non-wood fibers.

[0050] Example 1 (1) Tobacco Extract: Brazilian flue-cured tobacco was prepared as the tobacco raw material. 250 g of the tobacco raw material and 1,085 g of water were placed in a flask and stirred at 80°C for approximately 60 minutes to perform extraction. (2) Mixture: Other ingredients included wood pulp (softwood pulp), non-wood pulp (Helbasel AQ Plus CF-D / 100, manufactured by DSP Gokyo Food & Chemical Co., Ltd.), an aerosol source (glycerin), and a binder (cellulose derivatives: CMCF30MC, CMC350HC, manufactured by Nippon Paper Industries Co., Ltd., and guar gum: GRINDSTED 175, manufactured by DuPont Danisco). These were mixed with the tobacco extract to prepare a mixture. The blending ratios were as shown in Table 1. (3) Sheet: The mixture was cast onto a stainless steel plate and dried in an oven at 80°C to prepare a sheet with a cast thickness of 1.5 mm. The dried sheet was conditioned at 22°C and 60% RH overnight or more, and then visually evaluated for its ability to retain the liquid. The results are shown in Table 1.

[0051]

[0052] Sheets could be formed in all examples. However, the mixture (slurry) of Example 2, which had a liquid-solid ratio of 8, had low viscosity, and although it was within an acceptable range, workability was poor. Therefore, by using a binder that gave a slurry with a higher viscosity, workability improved (Example 3). Furthermore, when 27% non-wood pulp (Helbacell) was used, sheets could be produced with excellent workability even at a liquid-solid ratio of 7 (Example 4).

Claims

1. A method for producing an aerosol-generating sheet containing tobacco extract E and other component B, comprising the steps of: (1) preparing a mixture containing the tobacco extract E and another component B, which satisfies the following relationship: Liquid-solid ratio = weight of water in the mixture / weight of components other than water in the mixture ≧ 3 (2) obtaining a sheet from the mixture; A manufacturing method comprising:

2. The step (1) (1-1) A step of subjecting a tobacco raw material to a preliminary extraction with water to obtain a tobacco extract liquid L containing a tobacco extract E and water, and determining an extraction rate a defined by the following formula (1): Extraction rate a = Ed (E dry weight) / Td (dry weight of tobacco raw material) (1) (1-2) A step of determining X, which is the weight of water to be used in a new extraction carried out in the same manner as in step (1-1), based on the following formula (I): Liquid-solid ratio = (X / a) x t + (Bw / Bd) x (1-t) (I) (where, Liquid-solid ratio≧3 X = Ew (weight of water in tobacco extract L) / Td (weight of dry matter of tobacco raw material) Bw: total weight of water in all components B Bd: total weight of dry matter in all components B t = tobacco extract usage ratio = Ed / (Ed+Bd) (1-3) subjecting the tobacco raw material to extraction with water in an amount that satisfies X to obtain a tobacco extract; (1-4) mixing the tobacco extract obtained in (1-3) with the other components to prepare a mixture satisfying formula (I); Equipped with The method of claim 1.

3. The step (1) (1-1) A step of subjecting the tobacco raw material to a preliminary extraction with a mixed solvent containing water and alcohol to obtain a tobacco extract E and a tobacco extract liquid L' containing water and alcohol, and determining an extraction rate a' defined by the following formula (1'): Extraction rate a' = Ed (E dry weight) / Td ( tobacco raw material dry weight) (1') (1-2) A step of determining X, which is the weight of water to be used in a new extraction carried out in the same manner as in step (1-1), based on the following formula (I'): Liquid-solid ratio = (X / a') x t + (Bw / Bd) x (1-t) (I') (where, Liquid-solid ratio≧3 X = Ew (weight of water in the tobacco extract L') / Td (weight of the dry matter of the tobacco raw material) Bw: total weight of water in all components B Bd: total weight of dry matter in all components B t = tobacco extract usage ratio = Ed / (Ed+Bd) (1-3) determining the amount of the mixed solvent to be used for a new extraction from the weight ratio X, and subjecting the tobacco raw material to extraction using the determined amount of the mixed solvent to obtain a tobacco extract; (1-4) mixing the tobacco extract obtained in (1-3) with the other components to prepare a mixture satisfying formula (I'); Equipped with The method of claim 1.

4. The method according to any one of claims 1 to 3, wherein the aerosol-generating sheet contains 15 to 50% by weight of the tobacco extract on a dry basis.

5. said other component B comprising an aerosol source; 3. The method according to claim 1, wherein the aerosol-generating sheet contains 10 to 60% by weight of the aerosol source on a dry basis.

6. The manufacturing method according to claim 1 or 2, wherein the other component B comprises non-wood fiber, wood fiber, or a binder.

7. The method of claim 6, wherein the non-wood fiber is a dietary fiber.

8. The method of claim 7, wherein the non-wood fiber is a citrus fiber.

9. The method of claim 6, wherein the binder is a carboxyalkyl cellulose or a guar gum.

10. The method according to claim 6, wherein the content of said wood fibers is less than the content of said non-wood fibers.