EP4635306A1

EP4635306A1 - Tobacco-containing segment, smoking article, heating device, and non-combustion heating-type smoking system

Info

Publication number: EP4635306A1
Application number: EP22968369.3A
Authority: EP
Inventors: Kayoko IMAIIDA; Yuki MATSUTANI
Original assignee: Japan Tobacco Inc
Current assignee: Japan Tobacco Inc
Priority date: 2022-12-12
Filing date: 2022-12-12
Publication date: 2025-10-22
Also published as: JPWO2024127457A1; WO2024127457A1; KR20250094735A

Abstract

The present invention addresses the problem of providing a novel tobacco-containing segment that does not use a conventional cylindrical tobacco rod.The tobacco-containing segment is formed from one sheet and has a thickness greater than 70 µm but less than 1000 µm.

Description

TECHNICAL FIELD

The present invention relates to a tobacco-containing segment, a smoking article, a heating device, and a heat-not-burn smoking system.

BACKGROUND ART

Synthetic tobacco, a tobacco material that has been artificially shaped into paper form using leaf tobacco as a raw material, is also called a tobacco sheet. Examples of known methods for producing tobacco sheets include methods in which they are produced via a sheet-forming (paper making) process, methods in which they are produced via a slurry (casting) process, methods in which they are produced via a rolling (roll) process, and methods in which they are produced via an extrusion molding process.
It is believed that tobacco material that has been heated, rather than burned, results in smaller amounts of the more harmful compounds that are usually produced during smoking, and tobacco sheets for use in heated tobacco are also in high demand. Such tobacco sheets can be produced, based on the process described above, by combining a tobacco raw material, an aerosol former, and a binder, for example. Tobacco sheets produced in this way can be cut into a predetermined size and wrapped with wrapping paper, so that the resulting cut tobacco is inside, forming a cylindrical tobacco rod (PTL 1). Cylindrical tobacco rods may also be formed by gathering uncut tobacco sheets (PTL 2 through 4).
On the other hand, there are not many examples in which something other than a cylindrical tobacco rod is used. In PTL 5, for example, cut tobacco that has been formed into a rectangular shape is molded, and the resulting molded product is inserted into a special heated smoking device. As noted in PTL 6, a plurality of different tobacco sheets may also be laminated to form a laminated flavor-generating member, which is used by being inserted into a heating smoking device.

CITATION LIST

PATENT LITERATURE

PTL 1 WO 2017/081144 A1
PTL 2 JP 6403666 B2
PTL 3 JP 6580485 B2
PTL 4 JP 6668318 B2
PTL 5 WO 2019/162497 A1
PTL 6 WO 2018/235959 A1

SUMMARY OF INVENTION

TECHNICAL PROBLEM

However, in PTL 5, no consideration is given to the ease of insertion of the molded article into the insertion opening, and the relationship between the size of the molded article and the size of the insertion opening is unknown. Also, cases where a plurality of different tobacco sheets are laminated, as in PTL 6, are beset with problems, such as the fact that more laminating steps are required, the fact that any variation in the amount of the aerosol former and the thickness of the tobacco sheets forming the individual layers, for example, will be correspondingly reflected according to the number of laminated sheets, and the fact that the product will be correspondingly heavier and bulkier according to the number of laminated sheets.
As a result of extensive research undertaken by the inventors of the present application in view of the above circumstances, it was discovered that the formation of a tobacco-containing segment from a single sheet and the insertion thereof into a heating device resulted in the following advantages: a significantly lighter amount of tobacco is carried around in the form of a heated tobacco article, there is no concern over rods being bent, as happens with cylindrical tobacco rods; and packaging can be more compact. The present invention addresses the problem of providing a novel tobacco-containing segment that does not use a conventional cylindrical tobacco rod.

SOLUTION TO PROBLEM

As a result of extensive research to solve the above problems, the inventors perfected the present invention upon discovering that the above problems could be solved by forming a tobacco-containing segment from a single sheet having a specific thickness. Specific aspects of the present invention are as follows.

[1] A tobacco-containing segment consisting of one sheet and having a thickness greater than 70 µm and less than 1000 µm.
[2] The tobacco-containing segment according to [1], wherein the tobacco-containing segment has a square-shaped cross-section.
[3] The tobacco-containing segment according to [1] or [2], wherein the sheet comprises fibers derived from a plant raw material.
[4] The tobacco-containing segment according to [3], wherein the plant raw material comprises a tobacco raw material.
[5] The tobacco-containing segment according to any of [1] through [4], wherein the sheet is a cast sheet or a rolled sheet.
[6] The tobacco-containing segment according to any of [1] through [5], wherein the sheet comprises an aerosol former.
[7] The tobacco-containing segment according to [6], wherein the aerosol former comprises a polyol.
[8] The tobacco-containing segment according to [6] or [7], wherein the content of the aerosol former in the sheet is 10 to 80% by weight.
[9] The tobacco-containing segment according to any of [1] through [8], wherein the tobacco-containing segment does not comprise a wrapper.
[10] A smoking article comprising the tobacco-containing segment according to any of [1] through [9].
[11] The smoking article according to [10], which is a heat-not-burn smoking article.
[12] A heating device, comprising a body having a recess into which a tobacco-containing segment of a heat-not-burn smoking article is inserted, wherein the size of the gap in the recess is 0.2 to 2.0 mm.
[13] The heating device according to [12], wherein the cross-sectional shape of the recess is a square shape.
[14] The heating device according to [12] or [13], wherein the heat-not-burn smoking article is the heat-not-burn smoking article according to [11].
[15] A heat-not-burn smoking system comprising the heat-not-burn smoking article according to [11] and the heating device according to any of [12] through [14].
[16] The heat-not-burn smoking system according to [15], wherein the ratio of the size of the gap in the recess of the heating device relative to the thickness of the tobacco-containing segment of the heat-not-burn smoking article is 1.35 or more.

ADVANTAGEOUS EFFECTS OF INVENTION

The tobacco-containing segment of the present invention is a novel tobacco-containing segment that does not use a conventional cylindrical tobacco rod, resulting in the following advantages: a significantly lighter amount of tobacco is carried around in the form of a heated tobacco article; there is no concern over rods being bent, as happens with cylindrical tobacco rods; and packaging can be more compact.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a schematic view showing an example of a smoking segment.
Fig. 2 is a cross-sectional schematic view showing an example of a heat-not-burn smoking article.
Fig. 3 is a cross-sectional schematic view showing an example of a heat-not-burn smoking system.
Fig. 4 is a schematic view showing an example of a heating device.
Fig. 5 is a schematic view showing a device for assessing the insertability of a tobacco-containing segment into a heating device.

DESCRIPTION OF EMBODIMENTS

The tobacco-containing segment, heat-not-burn smoking article, heating device, and heat-not-burn smoking system of the present application are described below.

1. Tobacco-Containing Segment

The tobacco-containing segment of the present invention consists of one sheet and has a thickness greater than 70 µm and less than 1000 µm.
The thickness of the tobacco-containing segment is greater than 70 µm and less than 1000 µm, is preferably between 70 and 500 µm, is more preferably between 100 and 500 µm, and is ideally between 120 and 200 µm. Ensuring that the thickness of the tobacco-containing segment is within the above numerical range will result in a tobacco-containing segment quantity that affords better heat efficiency when heated and that can ensure a suitable number of smokes.
The width of the tobacco-containing segment is not particularly limited, but is preferably 5 to 20 mm, more preferably 7.5 to 17.5 mm, and ideally 1 to 15 mm. Ensuing that the width of the tobacco-containing segment is within the above numerical range will make it easier to pick up with just the fingertips and thus easier to insert into the device (heating device).
The length of the tobacco-containing segment is not particularly limited, but is preferably 40 to 90 mm, more preferably 50 to 75 mm, and ideally 50 to 60 mm. Ensuring that the length of the tobacco-containing segment is within the above numerical range will will result in a tobacco-containing segment quantity that can consistently be inserted into the device and that can ensure a suitable number of smokes.
The cross-sectional shape of the tobacco-containing segment is not particularly limited, but can be: rectangular or a square such as a regular square; diamond-shaped; or elliptical. Of these, a square shape is preferred. The use of a square shape can ensure a stable cutting surface and uniform quality.
The tobacco-containing segment may not include a wrapper. The use of a tobacco-containing segment that does not include a wrapper will allow heat to be directly transferred to the tobacco-containing segment.
The sheet described below can be used as such to produce a tobacco-containing segment.

(Sheet)

The tobacco-containing segment of the present invention consists of one sheet.
The various structural features, such as the size (thickness, width, and length) and cross-sectional shape, of the sheet can be the same as the various structural features of the tobacco-containing segment described above.
As used herein, "sheet" means a shape having a pair of substantially parallel main faces and side faces. The tobacco-containing segment or sheet can have a longitudinal direction, a widthwise direction and a thicknesswise direction, the sizes of which can be in the following order: "thicknesswise size (thickness)" < "widthwise size (width)" < "longitudinal size (length)."
Fig. 1 shows an example of a tobacco-containing segment (smoking segment) 20A (smoking composition sheet or material 21 derived therefrom). In Fig. 1, the T, W and L sizes correspond to the thickness, width, and length, respectively.
The sheet can comprise or consist of, but is not particularly limited to, plant raw material-derived fibers, binders, aerosol formers, or combinations of two or more of these. Of these, the use of plant raw material-derived fibers is preferred. The use of plant raw material-derived fibers will allow the structural skeleton of the sheet to be formed.
The above-mentioned plant raw materials can comprise or consist of, but are not particularly limited to, tobacco raw materials. The use of tobacco raw materials will allow the structural skeleton of the sheet to be formed, and the polysaccharides that are contained in the tobacco raw material will act as a binder, thus allowing the amount of externally added binder to be reduced.
The above tobacco raw material is raw material derived from a tobacco plant, such as tobacco leaf, aged tobacco leaf, cut tobacco, tobacco powder, tobacco raw material parts other than leaves, such as stems and stem waste, and processed or waste products obtained in the course of tobacco raw material processing. Tobacco leaf is a generic term for harvested tobacco leaves before they have been aged. One mode of ageing includes curing. Cut tobacco is aged tobacco leaf, for example, that has been cut to a predetermined size. Tobacco powder is tobacco leaves, for example, that have been ground.
A number of varieties of tobacco can be used as the tobacco raw material. Examples of tobacco varieties include flue-cured, Burley, orient, or native varieties, as well as Nicotiana tabacum and Nicotiana rustica varieties. These varieties can also be used alone, but in order to obtain a desired flavor, any varieties over the course from the harvest of tobacco leaves to the processing of the various types in which aged tobacco leaf is used in heat-not-burn tobacco products (specifically, processed tobacco leaves) can also be blended for use. Details on tobacco varieties are disclosed in "Dictionary of Tobacco, Tobacco Academic Studies Center, 2009.3.31."
As used herein, "tobacco leaf" is a generic term for harvested tobacco leaves before they have been aged. One mode of ageing includes curing.
By contrast, "aged tobacco leaf" refers to tobacco leaves that have been aged but that have not yet been processed into the various forms that are used in tobacco products (such as cut tobacco, tobacco sheets, and tobacco granules). Furthermore, "processed tobacco leaf" refers to aged tobacco leaves that have been processed into the various forms that are used in tobacco products.
The sheet can further comprise an aerosol former.
The aerosol former can comprise or consist of, but is not particularly limited to: polyols such as glycerol, 1, 2-propanediol, and 1, 3-propanediol; fatty acids such as medium-chain fatty acids and palmitic acid; or a mixture of two or more thereof. Of these, polyols are preferred. The use of a polyol will enable consistent smoke production.
The content of the aerosol former (included in the sheet) based on the entire sheet is not particularly limited, but is preferably 10 to 80% by weight, more preferably 15 to 60% by weight, and ideally 15 to 30% by weight. Ensuring that the aerosol former content is within the above numerical range will permit a sufficient number of smokes of approximately 10 to 20 puffs from the start of smoking.
The sheet can be obtained in the form of a tobacco sheet by molding a composition comprising aged tobacco leaf, for example, into the form of a sheet. There is no particular limitation as to the aged tobacco leaf used in the tobacco sheet, but aged tobacco leaf which has been de-stemmed and separated into lamina and midrib may be cited, for example.
The method for molding the sheet is not particularly limited, but fine tobacco powder, nicotine, a flavour development aid, and a binder, as well as an aerosol former and flavoring as needed, can be mixed, water can be added to the mixture to knead the materials, and the resulting kneaded product can be molded by a known method such as a sheet-forming method, casting method, or rolling method. Details on various types of sheets (tobacco sheets) molded by such methods are disclosed in "Dictionary of Tobacco, Tobacco Academic Studies Center, March 31, 2009".
In addition to the above components, the sheet can furthermore comprise antioxidants, terpenes, menthol, or a combination of two or more of these. Of these, the use of menthol is preferred. The use of menthol will allow invigorating smoking to be enjoyed.

2. Smoking Article

The smoking article of the present invention comprises the tobacco-containing segment described in "1. Tobacco-Containing Segment."
Examples of smoking articles (flavor inhalation articles) include smoking articles with which users taste flavors via inhalation, and smokeless cigarettes (smokeless smoking articles) with which users taste flavors, with the product held directly in the oral or nasal cavities. Smoking articles can be broadly divided into burning smoking articles, such as conventional cigarettes, and heat-not-burn smoking articles.
Examples of burning smoking articles include cigarettes, pipes, kiserus (Japanese smoking pipes), cigars, and cigarillos.
Heat-not-burn smoking articles (heated smoking articles) may be heated by a heating device that is separate from the article, or by a heating device that is integrated with the article. In the former type of smoking article (separate heating device), the heat-not-burn smoking article and the heating device are collectively referred to as a "heat-not-burn smoking system." An example of a heat-not-burn smoking system is described below with reference to Figs. 2 through 4.
Fig. 2 is a cross-sectional view of a heat-not-burn smoking article 20. As shown in Fig. 2, the heat-not-burn smoking article 20 (referred to below simply as "smoking article 20") has a flat shape corresponding to the sheet shape of the tobacco-containing segment described in " 1. Tobacco-Containing Segment" above. The thickness of the smoking article 20 is not particularly limited, but is preferably 70 to 500 µm, more preferably 100 to 500 µm, and ideally 120 to 200 µm. The width of the tobacco-containing segment is not particularly limited, but is preferably 0.5 to 20 mm, more preferably 0.75 to 20 mm, and ideally 10 to 17.5 mm. The total length (horizontal length) of the smoking article 20 is not particularly limited, but is preferably 40 mm to 150 mm, more preferably 50 mm to 90 mm, and even more preferably 50 mm to 70 mm.
The smoking article 20 consists of a smoking segment 20A and a filter portion 20C constituting the mouthpiece, which are connected by a connecting portion 20B.
The smoking segment 20A can be the tobacco-containing segment described in "1. Tobacco-Containing Segment" above. The various structural features, such as the size (thickness, width, and length) and cross-sectional shape, of the smoking segment 20A can be the same as the various structural features of the tobacco-containing segment described in "1. Tobacco-Containing Segment" above.
The cross-sectional shape of the filter portion 20C can be the same as the cross-sectional shape of the smoking segment 20A above. The filter portion 20C has a quadrilateral prism shape. The filter portion 20C has a quadrilateral prism-shaped first segment 25 that is made by being filled with cellulose acetate fibers, and a quadrilateral prism second segment 26 that is similarly made by being filled with cellulose acetate fibers. The first segment 25 is located on the smoking segment 20A side. The first segment 25 may have a hollow portion. The second segment 26 is located on the mouthpiece side. The second segment 26 is solid. The first segment 25 is composed of a first filling layer (cellulose acetate fibers) 25a and an inner plug wrapper 25b that is wrapped around the first filling layer 25a. The second segment 26 consists of a second filling layer (cellulose acetate fibers) 26a and an inner plug wrapper 26b that is wrapped around the second filling layer 26a. The first and second segments 25 and 26 are connected by an outer plug wrapper 27. The outer plug wrapper 27 is adhered to the first segment 25 and second segment 26 by a vinyl acetate emulsion-based adhesive, for example.
The length of the filter portion 20C can be 10 to 30 mm, for example, the length of the connecting portion 20B can be 10 to 30 mm, for example, the length of the first segment 25 can be 5 to 15 mm, for example, and the length of the second segment 26 can be 5 to 15 mm, for example. The lengths of these individual segments are examples, and can be modified, as appropriate, depending on, for example, the manufacturability, the required quality, and the length of the smoking segment 20A.
For example, the first segment 25 (centre hole segment) is composed of the first filling layer 25a having one or more hollow portions, and the inner plug wrapper 25b that covers the first filling layer 25a. The first segment 25 has the function of increasing the strength of the second segment 26. The first filling layer 25a of the first segment 25 is, for example, densely filled with cellulose acetate fibers. To the cellulose acetate fibers are added and cured a triacetin-containing plasticizer, in an amount of 6 to 20% by mass, for example, relative to the mass of the cellulose acetate. The hollow portion of the first segment 25 may, for example, have a cyclindrical shape having an inner diameter of φ 1.0 to φ 5.0 mm.
The first filling layer 25a of the first segment 25 may, for example, be configured with a relatively high fiber filling density, or may be the same as the fiber filling density of the second filling layer 26a of the second segment 26 described below. Thus, when drawn, air or aerosol will flow only through the hollow portion, and virtually no air or aerosol will flow through the first filling layer 25a. In cases where, for example, less of a filtration-induced reduction in the aerosol component is desired in the second segment 26, the length of the second segment 26 can be shortened, for example, to allow the first segment 25 to be lengthened accordingly.
Replacing the shortened second segment 26 with the first segment 25 will effectively increase aerosol delivery. The first filling layer 25a of the first segment 25 is a fiber filled layer, and the user therefore will not feel any discomfort when touching the outside during use.
The second segment 26 is composed of the second filling layer 26a and an inner plug wrapper 26b that covers the second filling layer 26a. The second segment 26 (filter segment) is filled with cellulose acetate fibers in a commonly used density, and has a commonly used aerosol filtration capacity.
The filtration capacity for filtering the aerosol (mainstream smoke) released from the smoking segment 20A may differ between the first segment 25 and the second segment 26. At least one of the first segment 25 or the second segment 26 may comprise flavouring. The filter portion 20C may have any structure, and may be a structure having a plurality of segments as described above, or may be composed of a single segment. The filter portion 20C may be composed of one segment. In such cases, the filter portion 20C may be composed of either the first segment or the second segment.
The cross-sectional shape of the connecting portion 20B can be the same cross-sectional shape of the smoking segment 20A described above. The connecting portion 20B has, for example, a quadrilateral prism shape. The connecting portion 20B has, for example, a paper tube 23 that is formed into a quadrilateral prism shape using cardboard, for example. The connecting portion 20B may be filled with a cooling member for cooling the aerosol. Examples of cooling members includes a sheet of a polymer such as polylactic acid, which can be folded and filled. A support that prevents the position of the smoking segment 20A from moving around may furthermore be provided between the smoking segment 20A and the connecting portion 20B. The support can be composed of known materials such as a centre hole filter of the kind in the first segment 25.
A wrapper 28 is wrapped in the form of a quadrilateral prism shape around the outside of the smoking segment 20A, the connecting portion 20B, and the filter portion 20C, to integrally join these parts. One surface (the inner surface) of the wrapper 28 is coated with a vinyl acetate-emulsion-based adhesive, over the entire surface or substantially the entire surface, except near the ventilation holes 24. A plurality of ventilation holes 24 are externally formed by a laser process after the smoking segment 20A, connecting portion 20B, and filter portion 20C have been integrated by the wrapper 28.
The ventilation holes 24 comprise two or more through-holes that pass through the connecting portion 20B in the thicknesswise direction. The two or more through-holes are formed so as to be radially arranged, as viewed along a line extending through the central axis of the smoking product 20. In the present embodiment, the ventilation holes 24 are provided in the connecting portion 20B, but may be provided in the filter portion 20C. In this embodiment, the two or more through-holes of the ventilation holes 24 are provided in a single row at a constant interval in a quadrilateral prism-shaped pattern, but may be provided in two rows at a constant interval in a quadrilateral prism-shaped pattern, where the one or two rows of the ventilation holes 24 may be provided discontinuously or irregularly. When a user holds the mouthpiece in the mouth and draws, outside air is taken into the mainstream smoke through the ventilation holes 24. However, no ventilation holes 24 need be provided.

3. Heating Device and Heat-Not-Burn Smoking System

An example of a heat-not-burn smoking system is shown in Fig. 3. As shown in the figure, the heat-not-burn smoking system comprises a heat-not-burn smoking article 20 and a heating device 10 which heats the smoking segment 20A from the outside. An enlarged view of the heating device is shown in Fig. 4.
The heating device 10 comprises: a body 11, a heater 12, a metal tube 13, a battery unit 14, and a control unit 15. The body 11 has a recess 16, where the heater 12 and metal tube 13 are disposed at positions facing the smoking segment 20A inserted therein. The heater 12 can be a heater employing electrical resistance, where heating by the heater 12 is effected by the supply of electrical power from the battery unit 14 per commands from the control unit 15, which controls the temperature. Heat emitted from the heater 12 is transferred through the highly thermoconductive metal tube 13 to the smoking segment 20A. The figure depicts an embodiment in which the heating device 10 heats the smoking segment 20A from the outside, but the segment may also be heated from the inside. The heating temperature of the heating device 10 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 12 of the heating device 10. The method of heating using the heating device is not particularly limited, and induction heating or microwave heating, for example, can be employed in addition to heating by the heater noted above.
The heating device of the present invention comprises a body having a recess into which a tobacco-containing segment of a heat-not-burn smoking article is inserted, wherein the size of the gap in the recess is 0.2 to 2.0 mm.
The size of the gap (thickness) of the recess in the heating device is preferably 0.2 to 2.0 mm (200 to 2000 µm), more preferably 0.25 to 2.0 mm (250 to 2000 µm), even more preferably 0.3 to 1.8 mm (300 to 1800 µm), and ideally 0.4 to 1.75 mm (400 to 1750 µm). Ensuring that the size of the gap of the recess in the heating device is within the above numerical range will result in smoother insertion of the tobacco sheet and will minimize loss of heat from the heating portion.
The width of the recess in the heating device is not particularly limited, but is preferably 6 to 25 mm, more preferably 7 to 22.5 mm, and ideally 8 to 21 mm. Ensuring that the width of the gap of the recess in the heating device is within the above numerical range will result in a sheet that is not bulky and can be smoothly inserted, and will minimize loss of heat from the heating portion.
The length of the recess in the heating device is not particularly limited, but is preferably 45 to 75 mm, more preferably 47 to 70 mm, and ideally 50 to 60 mm. Ensuring that the length of the gap of the recess in the heating device is within the above numerical range will result in a sheet that is not bulky when inserted and that can be uniformly heated after being inserted.
The cross-sectional shape of the recess in the heating device is not particularly limited, but can be: rectangular or a square such as a regular square; diamond-shaped; or elliptical. Of these, a square shape is preferred. The use of a square shape will result in the benefits of uniform heat transfer and easier design.
The various structural features, such as the size (gap (thickness), width, and length) and cross-sectional shape, of the recess in the heating device can correspond to the various structural features of the tobacco-containing segment that is inserted. In Fig. 4, the sizes of T', W' and L' correspond to the gap (thickness), width, and length, respectively, of the recess.
The heat-not-burn smoking article inserted into the heating device can be the heat-not-burn smoking article described in "2. Smoking Article" above.
The heat-not-burn smoking system of the present invention comprises the heat-not-burn smoking article described in "2. Smoking Article" above and the heating device noted above.
In the heat-not-bum smoking system, the ratio of the size of the gap in the recess of the heating device relative to the thickness of the tobacco-containing segment of the heat-not-burn smoking article (size of the gap in the recess/thickness of the tobacco-containing segment) is not particularly limited, but is preferably 1.35 or more, more preferably 1.4 to 1.7, and ideally 1.4 to 1.5. The ratio can be calculated using the same units (such as µm or mm) for both the units of the size of the gap in the recess and the units of the thickness of the tobacco-containing segment. Ensuring that the ratio is within the above numerical range can enhance the insertability of the tobacco-containing segment into the heating device.

EXAMPLES

The present invention will be described experimentally through the following examples, but the following description should not be construed as limiting the scope of the present invention to those examples.

EXAMPLE 1

(Preparation of Tobacco Sheet)

75 g of flue-cured tobacco leaf, 75 g of carboxymethyl cellulose, and 60 g of glycerol were mixed to obtain the tobacco raw material of Sample 1. The resulting tobacco raw material of Sample 1 was used to produce the tobacco sheet of Sample 1 based on a known sheet-making method. As shown in Table 1, the content of the components in the resulting tobacco sheets can be calculated as 35% by weight of tobacco leaf, 35% by weight of carboxymethyl cellulose, and 30% by weight of glycerol. As shown in Table 1, the resulting tobacco sheet of Sample 1 had a rectangular cross-sectional shape having a width of 15 mm, a thickness of 149 µm, and a length of 50 mm.
The tobacco raw materials of Samples 2 through 4 were obtained in the same manner as Sample 1, except that the amounts in which the components were added and the manufacturing conditions were changed so that the content of the components in the resulting tobacco sheets as well as the size (thickness, width, and length) and cross-sectional shape of the tobacco sheets were as shown in Table 1 below, and the tobacco sheets of Samples 2 through 4 were then produced based on a known sheet-making method. The values for the thickness of the tobacco sheets shown in Table 1 were obtained by averaging four thickness values determined using an Outside Micrometer M810-25 (by Mitutoyo Corporation) in four randomly selected locations on each sheet.

[Table 1]

Table 1

		Sample 1	Sample 2	Sample 3	Sample 4
Tobacco leaf	(% by weight)	35	10	78	70
Carboxymethyl cellulose	(% by weight)	35	10	10	5
Glycerol	(% by weight)	30	80	12	25
Total	(% by weight)	100	100	100	100

Tobacco sheet
Thickness	(µm)	149	172	193	1223
Width	(mm)	15	15	15	15
Length	(mm)	50	50	50	50
Cross section		rectangular	rectangular	rectangular	rectangular

One of each of the tobacco sheets of Samples 1 through 4 obtained in the manner noted above were made into tobacco-containing segments (smoking segment), and were used to produce heat-not-burn smoking articles as illustrated in Fig. 2. Meanwhile, the heating device shown in Fig. 4 (where the recess formed in the body had a width of 16 mm, a gap (thickness) of 1.5 mm, a depth (length) of 50 mm, and a rectangular cross-sectional shape) was prepared. The heat-not-burn smoking articles and heating devices of the above Samples 1 through 4 were installed in a heat-not-burn externally heated smoking system as shown in Fig. 3.
As indicated in PTL 1 through 4 noted above, tobacco sheets have conventionally been wrapped with wrapping paper to form cylindrical tobacco rods, which are inserted as tobacco-containing segments into heating devices. However, this sort of cylindrical tobacco rod tends to bend when external force is applied, and is at risk of becoming bent when carried around as a heated smoking article.
On the other hand, it can be seen that the formation of tobacco-containing segments from only a single tobacco sheet, as in Samples 1 through 4, resulted in tobacco sheets that were flexible and thus less likely to become bent, even when exposed to external force, as compared with conventional cylindrical tobacco rods. It can also be seen that the tobacco-containing segments of Samples 1 through 4 were formed from only a single tobacco sheet, and were lower in weight and volume, thus resulting in the benefits of a significantly lighter amount of tobacco being carried around in the form of a heated tobacco article, as well as the potential for more compact packaging.
It can furthermore be seen that the tobacco-containing segments (examples) of Samples 1 through 3, which had a thickness of less than 1000 µm, were that much thinner and lower in weight and volume compared with the tobacco-containing segment (example) of Sample 4, thus also resulting in the benefits of a significantly lighter amount of tobacco being carried around in the form of a heated tobacco article, as well as the potential for more compact packaging.

EXAMPLE 2

(Assessment of Insertability of Tobacco-Containing Segments into Heating Device)

In cases where the tobacco-containing segment is formed from only one tobacco sheet, the insertability of the tobacco-containing segment into the heating apparatus can be improved by appropriately designing the size of the gap in the recess of the heating device to suit the thickness of the tobacco-containing segment.
The insertability of the tobacco-containing segment into the heating device was assessed per the following procedure.

(Procedure)

An overview of the device used to assess insertability is shown in Fig. 5. The tobacco sheets 21 of Samples 1 to 4 described above were mounted on a stainless steel flat plate 30 (thickness: 0.5 mm; width: 15 mm; and length: 150 mm), and a standard simplified height gauge (H4-20, manufactured by Mitutoyo Corporation) was set up as a jig 40 thereon. Here, the above metal flat plate 30 and jig 40 were used based on the assumption that the recess of the heating device would generally be made of metal. The tobacco sheets were disposed between the flat plate 30 and the scriber 41 measuring surface (lower surface) of the jig 40 which had been set up as noted above, and the size of the gap between the flat plate 30 and the scriber 41 measuring surface of the fixture 40 (corresponding to the gap in the recess of the heating device) was set to the numerical values shown in Table 2 below.
The tobacco sheets 21 were moved in the widthwise direction (direction of the arrow in Fig. 5) relative to the flat plate 30 and the scriber 41 of the jig 40 to assess the insertability into the gap between the flat plate 30 and the scriber 41 measuring surface of the jig 40 as an assessment of the insertability into the heating device. Insertability was assessed based on the following criteria. The results are shown in Table 2 below. It can be said that the better the tobacco sheets 21 could be inserted into the gap, the better they could be inserted into the heating device.

(Assessment criteria)

A: The tobacco sheet could be smoothly moved into the gap.
B: The tobacco sheet could be moved in the gap, but not as smoothly as sheets rated A.
C: The tobacco sheet got caught and crumpled when attempts were made to move it into the gap.

The ratio of (2) the minimum gap (µm) required for an A rating relative to (1) the tobacco sheet thickness (µm) ((2)/(1)) was calculated for each tobacco sheet, The results are shown in Table 2.

[Table 2]

Table 2

Size of gap (µ m)	Sample 1	Sample 2	Sample 3	Sample 4
1800	A	A	A	A
1700	A	A	A	A
1600	A	A	A	B
300	A	A	A	C
260	A	A	A	C
240	A	A	B	C
220	A	B	C	C
200	B	C	C	C
100	C	C	C	C

(1) Tobacco sheet thickness (µ m)	149	172	193	1223
(2) Minimum gap (µ m) required for A rating	220	240	260	1700
(2)/(1)	1.48	1.40	1.35	1.39

The results of Table 2 show that tobacco sheets could be smoothly moved into the gap, and that the ratio of the minimum gap relative to tobacco sheet thickness was within a certain range when rated A. Specifically, tobacco sheets could be smoothly moved into the gap when the ratio of the minimum gap relative to the tobacco sheet thickness was 1.35 or more, as in Samples 1 through 4. The assessment results showed that setting the size of the gap in the recess of the heating device to 1.35 times or more relative to the tobacco sheet thickness allowed tobacco sheets to be more easily inserted into the heating device.
The tobacco sheets of Samples 1 through 3 in Table 2 were about the same thickness but had a very different glycerol (aerosol former) content of 30, 80 and 12% by weight, respectively. However, the results of Table 2 showed that that, despite such differences in glycerol content, the insertability of the tobacco sheets into the heating device was virtually unaffected and was dependent on only the size of the gap. It was thus confirmed that the content of the aerosol former, such as glycerol, could be freely designed within the numerical range of 10 to 80% by weight without adversely affecting the insertability of the tobacco sheet into the heating device.
As described above, the tobacco-containing segment of the present invention is a novel tobacco-containing segment that does not employ conventional cylindrical tobacco rods, and is useful as a tobacco-containing segment.

REFERENCE SIGNS LIST

10: Heating device
11: Body
12: Heater
13: Metal tube
14: Battery unit
15: Control unit
16: Recess
17: Ventilation holes

20: Heat-not-burn smoking article
20A: Smoking segment
20B: Connecting portion
20C: Filter portion

21: Smoking composition sheet or material derived therefrom
23: Paper tube
24: Ventilation holes
25: First segment
25a: First filling layer
25b: Inner plug wrapper
26: Second segment
26a: Second filling layer
26b: Inner plug wrapper
27: Outer plug wrapper
28: Wrapper

30: Flat plate
40: Jig
41: Scriber

Claims

A tobacco-containing segment consisting of one sheet and having a thickness greater than 70 µm and less than 1000 µm.
The tobacco-containing segment according to Claim 1, wherein the tobacco-containing segment has a square-shaped cross-section.
The tobacco-containing segment according to Claim 1 or 2, wherein the sheet comprises fibers derived from a plant raw material.
The tobacco-containing segment according to Claim 3, wherein the plant raw material comprises a tobacco raw material.
The tobacco-containing segment according to any of Claims 1 through 4, wherein the sheet is a cast sheet or a rolled sheet.
The tobacco-containing segment according to any of Claims 1 through 5, wherein the sheet comprises an aerosol former.
The tobacco-containing segment according to Claim 6, wherein the aerosol former comprises a polyol.
The tobacco-containing segment according to Claim 6 or 7, wherein the content of the aerosol former in the sheet is 10 to 80% by weight.
The tobacco-containing segment according to any of Claims 1 through 8, wherein the tobacco-containing segment does not comprise a wrapper.
A smoking article comprising the tobacco-containing segment according to any of Claims 1 through 9.
The smoking article according to Claim 10, which is a heat-not-burn smoking article.
A heating device, comprising a body having a recess into which a tobacco-containing segment of a heat-not-burn smoking article is inserted, wherein the size of the gap in the recess is 0.2 to 2.0 mm.
The heating device according to Claim 12, wherein the cross-sectional shape of the recess is a square shape.
The heating device according to Claim 12 or 13, wherein the heat-not-burn smoking article is the heat-not-burn smoking article according to Claim 11.
A heat-not-burn smoking system comprising the heat-not-burn smoking article according to Claim 11 and the heating device according to any of Claims 12 through 14.
The heat-not-burn smoking system according to Claim 15, wherein the ratio of the size of the gap in the recess of the heating device relative to the thickness of the tobacco-containing segment of the heat-not-burn smoking article is 1.35 or more.