EP4656075A1

EP4656075A1 - Aerosol generation device

Info

Publication number: EP4656075A1
Application number: EP23930688.9A
Authority: EP
Inventors: Kazutoshi SERITA; Takahiro Sakamoto; Hirofumi Matsumoto; Takafumi Izumiya
Original assignee: Japan Tobacco Inc
Current assignee: Japan Tobacco Inc
Priority date: 2023-03-31
Filing date: 2023-03-31
Publication date: 2025-12-03
Also published as: JPWO2024202054A1; WO2024202054A1

Abstract

An aerosol generation device into which there is inserted an aerosol-generating article that contains an aerosol source, the aerosol generation device comprising: a dielectric substrate having a first surface that faces toward the aerosol-generating article inserted into the aerosol generation device, and a second surface that is on the side opposite from the first surface; a first antenna disposed on the first surface of the dielectric substrate so as to emit electromagnetic waves toward a part of the aerosol-generating article; a first microstrip line disposed on the first surface of the dielectric substrate so as to transmit the electromagnetic waves to the first antenna; and a ground layer formed on the second surface of the dielectric substrate

Description

TECHNICAL FIELD

The present invention relates to an aerosol-generating device.

BACKGROUND ART

Recent years have seen a focus on heating methods for aerosol-generating devices such as heated tobacco, in which an aerosol-generating article (for instance a capsule or stick) containing an aerosol source is heated by microwave irradiation (e.g., see PTL 1).

CITATION LIST

PATENT LITERATURE

PTL 1: WO 2021/013477 A1

SUMMARY OF INVENTION

TECHNICAL PROBLEM

In aerosol-generating devices, electromagnetic wave (microwave) irradiation needs to be controlled at each position of an aerosol-generating article inserted into the device so that a desired heating distribution is formed in the aerosol-generating article. A configuration enabling the aerosol-generating article to be partially irradiated with electromagnetic waves would therefore be desirable.
The objective of the present invention therefore lies in providing an aerosol-generating device which enables an aerosol-generating article to be partially irradiated with electromagnetic waves.

SOLUTION TO PROBLEM

In order to achieve the objective above, an aerosol-generating device according to an embodiment of the present invention constitutes an aerosol-generating device into which an aerosol-generating article comprising an aerosol source is inserted, the aerosol-generating device being characterized by comprising: a dielectric substrate having a first face facing the aerosol-generating article inserted in the aerosol-generating device, and a second face on the opposite side to the first face; a first antenna arranged on the first face of the dielectric substrate so as to emit electromagnetic waves toward a portion of the aerosol-generating article; a first microstrip line arranged on the first face of the dielectric substrate so as to transmit the electromagnetic waves to the first antenna; and a ground layer formed on the second face of the dielectric substrate.

ADVANTAGEOUS EFFECTS OF INVENTION

The present invention makes it possible to provide an aerosol-generating device which enables an aerosol-generating article to be partially irradiated with electromagnetic waves.
Other features and advantages of the present invention will be become clearer through the following description given with reference to the appended drawings. It should be noted that identical or similar components are assigned the same reference numbers in the appended drawings.

BRIEF DESCRIPTION OF DRAWINGS

The appended drawings are included in and constitute part of the specification, illustrate embodiments of the present invention, and are used together with the descriptions to explain the principles of the present invention.

Fig. 1 is a schematic diagram showing a configuration example of an aerosol-generating device.
Fig. 2 is a schematic diagram showing a configuration example of an aerosol-generating device.
Fig. 3A shows a configuration example of a microstrip line and an antenna.
Fig. 3B shows a variant example of the microstrip line and the antenna.
Fig. 4 shows an arrangement of a plurality of antenna sets of Example 1.
Fig. 5 shows a variant example of the arrangement of the plurality of antenna sets.
Fig. 6 shows an arrangement of a plurality of antenna sets of Example 2.

DESCRIPTION OF EMBODIMENTS

Embodiments will be described in detail below with reference to the appended drawings. It should be noted that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are essential to the invention. Furthermore, two or more of the plurality of features described in the embodiments may be combined in any way. Furthermore, identical or similar components are assigned the same reference numbers and descriptions thereof will not be repeated.
An aerosol-generating device 10 according to an embodiment of the present invention will be described with reference to fig. 1 and 2. Fig. 1 and 2 are schematic diagrams showing a configuration example of the aerosol-generating device 10 according to this embodiment. Fig. 1 shows the aerosol-generating device 10 before an aerosol-generating article 30 and a mouthpiece 40 have been attached, and fig. 2 shows the aerosol-generating device 10 after the aerosol-generating article 30 and the mouthpiece 40 have been attached. Fig. 1 and 2 show directions in an XYZ coordinate system where a direction of insertion of the aerosol-generating article 30 into the aerosol-generating device 10 is the -Z direction. Furthermore, the "θ direction" used in the following description indicates a circumferential direction (i.e., a circumferential direction about the Z axis) of the aerosol-generating article 30 inserted in the aerosol-generating device 10.
The aerosol-generating device 10 is configured to heat the aerosol-generating article 30 in response to an operation requesting atomization of an aerosol source (also referred to as an atomization request), such as a user inhalation action, and to provide the user with a vapor containing an aerosol or a vapor containing an aerosol and a flavor substance. The aerosol-generating device 10 may be referred to as an inhaler (atomizer), and the aerosol-generating device 10 may be designated as the "inhaler 10" in the following description.
The aerosol-generating article 30 is an article containing an aerosol source which generates an aerosol by means of heating, and is detachably fitted in the inhaler 10 (fitted in such a way as to be capable of insertion/withdrawal). The aerosol-generating article 30 may also contain, in addition to the aerosol source, a flavor source for generating a flavor substance by means of heating. The flavor source may be a plant other than tobacco, for example mint, Chinese herbs, or herbs, etc. In this embodiment, the aerosol-generating article 30 is configured as a tobacco stick in the form of a substantially cylindrical rod, but it does not have to be stick-shaped and may equally be capsule-shaped or cartridge-shaped. The aerosol-generating article 30 may be referred to as a "tobacco stick 30" below.

Configuration of tobacco stick

The tobacco stick 30 may comprise, for example: a tobacco filling portion 31 (tobacco rod portion), a mouthpiece portion 32, and a tipping paper 33 that integrally links the components together. The tobacco filling portion 31 comprises a tobacco filling material comprising the aerosol source and the flavor source. The mouthpiece portion 32 is linked coaxially to the tobacco filling portion 31 by being wrapped together with the tobacco filling portion 31 by the tipping paper 33. The tobacco stick 30 has a substantially constant diameter over the entire length in the Z-axis direction (longitudinal direction). Note that a filter for stopping the tobacco filling material from falling out may also be provided at an end portion of the tobacco stick 30 upstream of the tobacco filling portion 31.

Tobacco filling portion

There is no particular restriction on the configuration of the tobacco filling portion 31, and it may take a general form. For example, a tobacco filling material wrapped with a rolling paper may be used as the tobacco filling portion 31.
The tobacco filling material comprises, as the flavor source, tobacco leaves or tobacco leaf extract, or processed articles thereof, for example. In this embodiment, the tobacco filling material is configured to contain shredded tobacco. There is no particular limitation as to the material of the shredded tobacco contained in the tobacco filling material, and well-known materials such as lamina and midrib can be used. Furthermore, ground tobacco may be formed by grinding dried tobacco leaves to an average particle size of 20 µm-200 µm, then homogenized and processed into a sheet (also referred to below simply as a "homogenized sheet") which is shredded, and ground tobacco may be extruded or tableted. In addition, a tobacco rod may be filled with a material obtained by shredding, in the longitudinal direction of the tobacco rod and substantially horizontally, a homogenized sheet having a length similar to that of the tobacco rod in the longitudinal direction, forming what is known as a "strand-type" filling material. Furthermore, the width of the shredded tobacco is preferably 0.5 mm-2.0 mm in order to fill the tobacco filling portion 31. Furthermore, there is no particular restriction on the content of dried tobacco leaves in the tobacco filling portion 31, but between 200 mg/rod portion and 800 mg/rod portion may be cited, and between 250 mg/rod portion and 600 mg/rod portion is preferred. This range is particularly suitable if the tobacco filling portion 31 has a circumference of 22 mm and a length of 20 mm. Moreover, depending on the shape of the aerosol-generating article 30, a mixed liquid of glycerol, nicotine and flavoring materials, etc., or a glass fiber nonwoven fabric impregnated with such a liquid may also be used as the tobacco filling material.
Various types of tobacco used can be used for the tobacco leaves used in the production of the shredded tobacco and the homogenized sheet. Examples that may be cited include yellow, Burley, orient, or native type, and other Nicotiana tabacum and Nicotiana rustica varieties, and mixtures thereof. A suitable blend of the abovementioned varieties may be used in a mixture to achieve the intended taste. Details on tobacco varieties are disclosed in "Dictionary of Tobacco, Tobacco Academic Studies Center, March 31, 2009". There are multiple conventional methods for producing the homogenized sheet, that is, methods for grinding tobacco leaves and processing them into a homogenized sheet. According to a first method, a paper sheet is produced by using a papermaking process. According to a second method, a suitable solvent such as water is mixed with ground tobacco leaves and homogenized, after which the homogenized material is thinly cast on a metal plate or a metal plate belt and dried, to produce a cast sheet. According to a third method, a suitable solvent such as water is mixed with ground tobacco leaves and homogenized, and the homogenized material is extruded into the form of a sheet and shaped to produce a calendered sheet. Details on types of homogenized sheets are disclosed in "Dictionary of Tobacco, Tobacco Academic Studies Center, March 31, 2009".
The amount of moisture contained in the tobacco filling material may be cited as 10 wt%-15 wt%, and preferably 11 wt%-13 wt% with respect to the total weight of the tobacco filling material. A moisture content such as this suppresses formation of wrapping stains and improves rolling suitability when the tobacco filling portion 31 is produced. There is no particular restriction on the size or method of preparation of the shredded tobacco contained in the tobacco filling material. For example, a material obtained by shredding dried tobacco leaves to a width of 0.5 mm or more and 2.0 mm or less may be used. Furthermore, when ground material is used in the homogenized sheet, a sheet may be formed by grinding dried tobacco leaves to an average particle size of approximately 20 µm to 200 µm and then homogenizing the ground tobacco, and the homogenized sheet may be shredded to a width of 0.5 mm or more and 2.0 mm or less for use.
The tobacco filling material comprises an aerosol base material for generating aerosol smoke. There is no particular restriction on the type of aerosol base material, and extracts from various types of natural products and/or components thereof may be selected in accordance with the application. Aerosol base materials which may be cited include water, glycerol, propylene glycol, triacetin, 1,3-butanediol, and mixtures thereof. There is no particular limitation as to the amount of the aerosol base material contained in the tobacco filling material, and the amount is normally 5 wt% or greater and preferably 10 wt% or greater, and normally 50 wt% or less, and preferably 15 wt% or greater and 25 wt% or less, with respect to the total amount of tobacco filling material, from the viewpoint of sufficient aerosol generation and imparting a good flavor.
The tobacco filling material may contain a flavoring material. There is no particular limitation as to the type of flavoring material, and, from the point of view of imparting a pleasant flavor, there may be cited: 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-carvone, β-caryophyllene, cassia bark oil, cedar wood oil, celery seed oil, chamomile oil, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, cinnamyl cinnamate, citronella oil, DL-citronellol, clary sage extract, cocoa, coffee, cognac 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-6-octenoic acid, 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethyl 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-hydroxy-4-methyl-2(5H)-furanone, 2-ethyl-3-methylpyrazine, eucalyptol, fenugreek absolute, genet absolute, gentian root infusion, geraniol, geranyl acetate, grape juice, guaiacol, guava extract, γ-heptalactone, γ-hexalactone, hexanoic acid, cis-3-hexen-1-ol, hexyl acetate, hexyl alcohol, hexyl phenylacetate, 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, 4-hydroxyundecanoic acid sodium, immortelle absolute, β-ionone, isoamyl acetate, isoamyl butyrate, isoamyl phenylacetate, isobutyl acetate, isobutyl phenylacetate, jasmine absolute, kola nut tincture, labdanum oil, lemon terpeneless oil, glycyrrhiza extract, linalool, linalyl acetate, lovage root oil, maltol, maple syrup, menthol, menthone, acetic acid L-menthyl, paramethoxybenzaldehyde, methyl-2-pyrrolyl ketone, methyl anthranilate, methyl phenylacetate, methyl salicylate, 4'-methylacetophenone, methylcyclopentenolone, 3-methylvaleric acid, mimosa absolute, molasses, myristic acid, nerol, nerolidol, γ-nonalactone, nutmeg oil, δ-octalactone, octanal, octanoic acid, orange flower oil, orange oil, orris root oil, palmitic acid, ω-pentadecalactone, peppermint oil, petitgrain Paraguay oil, phenethyl alcohol, phenethyl phenylacetate, phenylacetic acid, piperonal, plum extract, propenyl guaethol, propyl acetate, 3-propylidene phthalide, prune juice, pyruvic acid, raisin extract, rose oil, rum, sage oil, sandalwood oil, spearmint oil, styrax absolute, marigold oil, tea distillate, α-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-cyclohexen-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-carboamide (WS-3), and ethyl-2-(p-menthane-3-carboxamide) acetate (WS-5), with menthol being especially preferred. One of these flavoring materials may be used alone, or two or more may be used in combination.
There is no particular limitation as to the amount of flavoring contained in the tobacco filling material, and, from the point of view of imparting a good flavor, the content is normally 10,000 ppm or greater, preferably 20,000 ppm or greater, and more preferably 25,000 ppm or greater, and is normally 70,000 ppm or less, preferably 50,000 ppm or less, more preferably 40,000 ppm or less, and even more preferably 33,000 ppm or less.
The rolling paper is a sheet material for wrapping the tobacco filling material, and there is no particular restriction on the composition thereof, and a common rolling paper can be used. For example, cellulose fiber paper can be used as the base paper used for the rolling paper, and more specifically hemp or wood, or mixtures thereof, can be cited. The basis weight of the base paper of the rolling paper is normally 20 gsm or greater, and preferably 25 gsm or greater, for example. Meanwhile, the basis weight is normally 65 gsm or less, preferably 50 gsm or less, and even more preferably 45 gsm or less. There is no particular limitation as to the thickness of the rolling paper having the characteristics above, but it is normally 10 µm or greater, preferably 20 µm or greater, and more preferably 30 µm or greater, and furthermore is normally 100 µm or less, preferably 75 µm or less, and more preferably 50 µm or less, from the viewpoint of rigidity and air permeability, and ease of making adjustments during papermaking.
Square or rectangular may be cited as shapes of the rolling paper of the tobacco filling portion 31 (tobacco filling material). When used as the rolling paper for wrapping the tobacco filling material (for producing the tobacco filling portion 31), one side may have a length of around 6 mm-70 mm, and the other side may have a length of 15 mm-28 mm, preferably a length of 22 mm-24 mm, and even more preferably a length of around 23 mm.
In addition to the abovementioned pulp, the rolling paper may also comprise a loading material. The content of the loading material may be 10 wt% or greater and less than 60 wt%, and is preferably 15 wt%-45 wt%, with respect to the total weight of the rolling paper. In the rolling paper, the content of the loading material is preferably 15 wt%-45 wt% within the preferred basis weight range (25 gsm-45 gsm). In addition, if the basis weight is 25 gsm-35 gsm, then the content of the loading material is preferably 15 wt%-45 wt%, and if the basis weight is greater than 35 gsm and no greater than 45 gsm, then the content of the loading material is preferably 25 wt%-45 wt%. Calcium carbonate, titanium dioxide, or kaolin, etc. may be used as the loading material, but calcium carbonate is preferably used from the point of view of improving flavour and whiteness, etc.
Various auxiliaries other than the base paper and the loading material may also be added to the rolling paper, for example water-resistance improving agents can be added to improve water resistance. A water-resistance improving agent contains a wet-strength agent (WS agent) and a sizing agent. Examples of wet strength agents include urea formaldehyde resins, melamine formaldehyde resins, polyamide epichlorohydrin (PAE), and the like. Furthermore, examples of sizing agents include rosin soap, alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), and highly saponified polyvinyl alcohol having a saponification degree of 90% or more. A paper strength agent may be added as an auxiliary, for example polyacrylamide, cationic starch, oxidized starch, CMC, polyamide epichlorohydrin resin, or polyvinyl alcohol. Using a minute amount of oxidized starch in particular is known to improve air permeability (e.g., see JP 2017-218699 A ). The rolling paper may also be coated as appropriate.
A coating agent may be added to at least one of the two surfaces of the rolling paper, namely the front surface and the rear surface. There is no particular restriction on the coating agent, but a coating agent that can form a film on the surface of the paper and reduce the permeability of liquids is preferred. Examples include polysaccharides such as alginic acid and salts thereof (e.g., sodium salt), and pectin; cellulose derivatives such as ethyl cellulose, methyl cellulose, carboxymethyl cellulose, and nitrocellulose; and starch and derivatives thereof (e.g., ether derivatives such as carboxymethyl starch, hydroxyalkyl starch, and cationic starch, and ester derivatives such as acetate starch, phosphate starch, and octenyl succinate starch).
The Z-axis direction length of the tobacco filling portion 31 may be appropriately varied according to the size of the product, but it is, for example, 5 mm or greater, preferably 10 mm or greater, more preferably 12 mm or greater, and even more preferably 18 mm or greater, and furthermore is normally 70 mm or less, preferably 50 mm or less, more preferably 30 mm or less, and even more preferably 25 mm or less.

Mouthpiece portion

There is no particular restriction on the configuration of the mouthpiece portion 32, and it may take a general form. For example, the mouthpiece portion 32 may be configured to include two segments (sections) comprising a cooling segment and a filter segment. The cooling segment and the filter segment are aligned along the Z-axis direction (longitudinal direction) so that the cooling segment is positioned closer to the tobacco filling portion 31 than the filter segment. That is to say, the cooling segment is arranged so as to be interposed between the tobacco filling portion 31 and the filter segment in the Z-axis direction. The mouthpiece portion 32 may be configured so that the cooling segment abuts the tobacco filling portion 31 and the filter segment, or may be configured so that a gap is formed between the tobacco filling portion 31 and the cooling segment, and between the cooling segment and the filter segment 122, respectively. Furthermore, the mouthpiece portion 32 may be formed from a single segment.
There is no particular restriction on the configuration of the cooling segment of the mouthpiece portion 32, provided that it has the function of cooling tobacco mainstream smoke, and cardboard processed into a cylindrical shape can be cited, for example. In this case, the inside of the cylinder is a hollow, and vapor containing the aerosol base material and a tobacco flavor component comes into contact with air inside the hollow and is cooled.
According to one mode, the cooling segment may be a paper tube obtained by processing one sheet of paper or multiple bonded sheets of paper into a cylindrical shape. Furthermore, holes for introducing room-temperature external air are preferably present around the paper tube in order to increase the cooling effect afforded by contact between the external air and the high-temperature vapor. That is to say, ventilation holes, which are openings for taking in air from the outside, are provided in the cooling segment. There is no particular limitation as to the number of ventilation holes in the cooling segment. In this embodiment, a plurality of ventilation holes are arranged at fixed intervals in a circumferential direction of the cooling segment. Furthermore, groups of ventilation holes arrayed in the circumferential direction of the cooling segment may be formed in multiple stages along the Z-axis direction of the cooling segment. Providing the ventilation holes in the cooling segment enables low-temperature air to flow into the cooling segment from the outside when the user draws on the tobacco stick 30, and it is possible to lower the temperature of air and volatile components flowing in from the tobacco filling portion 31. Furthermore, the vapor containing the aerosol base material and tobacco flavor component condenses as a result of being cooled by the low-temperature air introduced into the cooling segment through the ventilation holes. By this means, aerosol generation is promoted while it is also possible to control the size of aerosol particles. The cooling effect may also be increased by utilizing heat absorption by a coating or heat of solution associated with a change of phase, by coating an inside surface of the paper tube with a polymer coating such as polyvinyl alcohol or a polysaccharide coating such as pectin. The airflow resistance of the cylindrical cooling segment is 0 mmH₂O.
When the cooling segment of the mouthpiece portion 32 is filled with a sheet, etc. for cooling air and volatile components flowing into the cooling segment from the tobacco filling portion 31, there is no particular restriction on the total surface area of the cooling segment, and it may be 300 mm²/mm-1000 mm²/mm, for example. This surface area is the surface area per length (mm) of the cooling segment in the air flow direction. The total surface area of the cooling segment is preferably 400 mm²/mm or greater and more preferably 450 mm²/mm or greater, while preferably being 600 mm²/mm or less, and more preferably 550 mm²/mm or less.
The internal structure of the cooling segment preferably has a large total surface area. Accordingly, in a preferred embodiment, the cooling segment may be formed by a sheet which is a thin material that is crimped and then pleated, gathered, and folded to form channels. The more folds or pleats within a given volume of the element, the greater the total surface area of the cooling segment. There is no particular restriction on the thickness of the material constituting the cooling segment, and it may be 5 µm-500 µm, or may be 10 µm-250 µm, for example.
It is also desirable to use paper as the material of the cooling sheet member from the perspective of reducing the environmental burden. The paper serving as the cooling sheet material preferably has a basis weight of 30-100 g/m² and a thickness of20-100 µm. From the perspective of reducing removal of the flavor source component and aerosol base material component in the cooling segment, the paper serving as the cooling sheet material preferably has low air permeability, and an air permeability of 10 CORESTA units or less is preferred. The cooling effect may also be increased by utilizing heat absorption by a coating or heat of solution associated with a change of phase, by coating the paper serving as the cooling sheet material with a polymer coating such as polyvinyl alcohol or a polysaccharide coating such as pectin.
The ventilation holes in the cooling segment are preferably arranged at a position at least 4 mm away from a boundary between the cooling segment and the filter segment. This makes it possible not only to improve the cooling ability of the cooling segment, but also to suppress stagnation of components generated by means of heating inside the cooling segment, and to increase the amount of delivery of those components. Moreover, openings are preferably provided in the tipping paper 33 at positions directly above (positions vertically overlapping) the ventilation holes provided in the cooling segment. The ventilation holes (openings) in the cooling segment are preferably provided so that a ratio of inflow air from the ventilation holes during drawing at 17.5 mL/second on an automatic smoking machine (a volume ratio of air flowing in from the ventilation holes when the proportion of air drawn from the mouthpiece end is 100 vol%) is 10-90 vol%, preferably 50-80 vol%, and more preferably 55-75 vol%, for example, the number of ventilation holes per group of ventilation holes may be selected from a range of 5-50 ventilation holes, the diameter of the ventilation holes may be selected from a range of 0.1-0.5 mm, and the above ratio may be achieved by a combination of these selections. The air inflow ratio may be measured by a method based on ISO9512, using an automatic smoking machine (e.g., a 1-port smoking machine, manufactured by Borgwaldt). There is no particular limitation as to the length of the cooling segment in the Z-axis direction (air flow direction), but it is normally 10 mm or greater and preferably 15 mm or greater and furthermore is normally 40 mm or less, preferably 35 mm or less, and more preferably 30 mm or less. The length of the cooling segment in the Z-axis direction is particularly preferably 20 mm. It is possible to ensure a sufficient cooling effect and to obtain a pleasant flavor by setting the length of the cooling segment in the Z-axis direction at no less than the abovementioned lower limit. Furthermore, by setting the length of the cooling segment in the Z-axis direction at no greater than the abovementioned upper limit, it is possible to inhibit loss caused by adhesion of the vapor and aerosol generated during use to the inner wall of the cooling segment.
There is no particular restriction on the configuration of the filter segment of the mouthpiece portion 32 provided that it has the function of a general filter, and cellulose acetate tow processed into a cylindrical shape can be cited, for example. There is no particular limitation on the single-yarn fineness or the total fineness of the cellulose acetate tow, but in the case of a filter segment having a circumference of 22 mm, the single-yarn fineness is preferably 5 to 20 g/9000 m, and the total fineness is preferably 12,000 to 30,000 g/9000 m. The cross-sectional shape of the fibers of cellulose acetate tow may be either a Y cross section or an R cross section. When the filter segment is formed by packing with cellulose acetate tow, triacetin may be added in an amount of 5-10 wt% with respect to the weight of cellulose acetate tow in order to increase the filter hardness. The filter segment may be formed from a single segment or may be formed from multiple segments. In an exemplary mode of a filter segment formed from multiple segments which may be cited, a hollow segment such as a center hole may be arranged on the upstream side (tobacco filling portion 31 side), and an acetate filter packed with cellulose acetate tow in a mouthpiece cross section may be arranged as a segment on the downstream side (mouthpiece end side), for example. By virtue of this mode, it is possible to prevent needless loss of the generated aerosol while also improving the appearance of the tobacco stick 30. Furthermore, a mode in which an acetate filter is arranged on the upstream side (tobacco filling portion 31 side) and a hollow segment such as a center hole is arranged on the downstream side (mouthpiece end side) is also possible from the perspectives of a sensory change in draw satisfaction and comfort when holding the article in the mouth. Furthermore, instead of an acetate filter, it is also possible to adopt a mode in which the filter segment employs a paper filter filled with sheet-like paper pulp, or another alternative filter.
Examples of general functions of the filter in the filter segment which may be cited include adjusting the amount of air which is mixed when the aerosol, etc. is inhaled, lightening the flavor, and lightening nicotine and tar, etc., but not all of these functions need to be provided. Preventing tobacco filling material from falling out as the filtration function is controlled is also another important function in electrically heated tobacco products, which generate fewer components and tend to have a lower filling rate of tobacco filling material than paper-wrapped tobacco products.
The filter segment has a substantially circular shape in its transverse cross section, and the diameter of the circle may be suitably varied according to the size of the product, but it is normally 4.0 mm-9.0 mm, preferably 4.5 mm-8.5 mm, and more preferably 5.0 mm-8.0 mm. It should be noted that when the cross section is non-circular, the abovementioned diameter is assumed for a circle having the same area as the area of the relevant cross section, and the diameter of that circle is applied. The circumferential length of the filter segment may be suitably varied according to the size of the product, but it is normally 14.0 mm-27.0 mm, preferably 15.0 mm-26.0 mm, and more preferably 16.0 mm-25.0 mm. The length of the filter segment in the Z-axis direction may be varied according to the size of the product, but is normally 5 mm-35 mm, and preferably 100 mm-30.0 mm. The shape and dimensions of the filter medium may be suitably adjusted so that the shape and dimensions of the filter segment lie within the range above.
There is no particular restriction on the airflow resistance per 120 mm Z-axis direction length of the filter segment, but it is normally 40 mmH₂O-300 mmH₂O, preferably 70 mmH₂O-280 mmH₂O, and more preferably 90 mmH₂O-260 mmH₂O. The airflow resistance is measured by using a filter airflow resistance measurement instrument manufactured by Cerulean, for example, in accordance with the ISO standard method (ISO 6565). The airflow resistance of the filter segment denotes an air pressure difference between one end face (a first end face) and another end face (a second end face) when air at a predetermined air flow rate (17.5 cc/min) flows from the first end face to the second end face in a state in which air does not pass through the side face of the filter segment. The units of airflow resistance are generally expressed in mmH₂O. The relationship between airflow resistance of the filter segment and length of the filter segment is known to be a proportional relationship in a normal length range (a length of 5-200 mm), and the airflow resistance of the filter segment also doubles when the length doubles.
Furthermore, there is no particular restriction on the density of the filter medium in the filter segment, but it is normally 0.10 g/cm³-0.25 g/cm³, preferably 0.11 g/cm³-0.24 g/cm³, and more preferably 0.12 g/cm³-0.23 g/cm³. The filter segment may comprise a wrapping paper (filter plug wrapping paper) wrapped around the filter medium, etc., from the point of view of improving strength and structural rigidity. There is no particular restriction on the form of the wrapping paper, which may include a seam including one or more lines of adhesive. The adhesive may comprise a hot-melt adhesive, and further, the hot-melt adhesive may comprise polyvinyl alcohol. Furthermore, when the filter segment comprises two or more segments, the wrapping paper is preferably wrapped around both of these two or more segments. There is no particular restriction on the material of the wrapping paper for the filter segment, and well-known materials may be used, and the wrapping paper may furthermore include a filler such as calcium carbonate, etc.
There is no particular restriction on the thickness of the wrapping paper, and it is normally 20 µm-140 µm, preferably 30 µm-130 µm, and more preferably 30 µm-120 µm. There is no particular restriction on the basis weight of the wrapping paper, and it is normally 20 gsm-100 gsm, preferably 22 gsm-95 gsm, and more preferably 23 gsm-90 gsm. Furthermore, the wrapping paper may be coated or uncoated, but is preferably coated with a desired material from the viewpoint of allowing functions other than strength and structural rigidity to be imparted.
If the filter segment comprises a center hole segment and a filter medium, then the center hole segment and the filter medium may be connected by an outer plug wrapper (outside wrapping paper), for example. The outer plug wrapper may be cylindrical paper, for example. Furthermore, the tobacco filling portion 31, the cooling segment, and the connected center hole segment and filter medium may also be connected by means of a mouthpiece lining paper, for example. These connections may be formed, for example, by coating an inside surface of the mouthpiece lining paper with a glue such as a vinyl acetate-based glue, and inserting the tobacco filling portion 31, the cooling segment, and the connected center hole segment and filter medium which are then wrapped with the mouthpiece lining paper. It should be noted that these elements may also be connected by multiple separate connections with multiple lining papers.
The filter medium in the filter segment may comprise a frangible additive release container (e.g., a capsule) comprising a frangible outer shell, such as gelatin. There is no particular restriction on the form of the capsule (also referred to as an "additive release container" in this technical field), and a well-known form may be adopted, for example, it is possible to use a frangible additive release container comprising a frangible shell such as gelatin. There is no particular limitation as to the form of the capsule, and it may be an easily-rupturable capsule, for example, and the shape thereof is preferably spherical. Any of the abovementioned additives may be contained as the additive included in the capsule, but a flavorant or activated carbon is especially preferably contained. Examples of flavorants include: menthol, spearmint, peppermint, fenugreek, or clove, and medium-chain fatty acid triglycerides (MCT), etc., or a combination thereof. Furthermore, one or more types of materials serving as an aid to filtering smoke may be added as an additive. There is no particular limitation as to the form of the additive, and it is normally a liquid or a solid. It should be noted that use of a capsule containing an additive is well known in this technical field. Easily-rupturable capsules and methods for producing same are well known in this technical field.
The flavoring material may be added to the filter medium in the filter segment. By adding the flavoring material to the filter medium, the amount of flavoring material delivered during use is increased as compared to the prior art, where flavoring material is added to the tobacco filling material constituting the tobacco filling portion 31. The degree of increase in the amount of flavoring material delivered further increases according to the positions of the ventilation holes (openings) provided in the cooling segment. There is no particular restriction on the method of adding the flavoring material to the filter medium, and the flavoring material should be added so as to be roughly uniformly dispersed in the filter medium which has the flavoring material added thereto. As the amount of flavoring material added, there may be cited a form in which the flavoring material is added to a 10-100 vol% portion of the filter medium. The method of addition may comprise adding the flavoring material in advance to the filter medium, before the filter segment is constructed, or adding the flavoring material after the filter segment has been constructed. There is no particular limitation as to the type of flavoring material, but the same flavoring material as is contained in a tobacco filling material may be used.
The filter segment may comprise the filter medium, and activated charcoal may be added to at least a portion of this filter medium. The amount of activated charcoal which is added to the filter medium may be 15.0 m²/cm²-80.0 m²/cm², as a value which is specific surface area of activated charcoal × weight of activated charcoal / cross-sectional area of filter medium in a direction perpendicular to air flow direction, in one tobacco stick 30. For convenience, the abovementioned "specific surface area of activated charcoal × weight of activated charcoal / cross-sectional area of filter medium in a direction perpendicular to air flow direction" may also be expressed as "surface area of activated charcoal per unit cross-sectional area". The surface area of activated charcoal per unit cross-sectional area may be calculated on the basis of the specific surface area of the activated charcoal added to the filter medium of one tobacco stick 30, the weight of activated charcoal added, and the cross-sectional area of the filter medium. It should be noted that the activated charcoal need not be uniformly dispersed in the filter medium to which it is added, and it is not necessary for the range above to be satisfied over the entire cross section of the filter medium (the cross section in a direction perpendicular to the air flow direction).
The surface area of activated charcoal per unit cross-sectional area is more preferably 17.0 m²/cm² or greater, and even more preferably 35.0 m²/cm² or greater. Meanwhile, the surface area of activated charcoal per unit cross-sectional area is more preferably 77.0 m²/cm² or less, and even more preferably 73.0 m²/cm² or less. The surface area of activated charcoal per unit cross-sectional area may be adjusted, for example, by adjusting the specific surface area of the activated charcoal and the added amount thereof, and by adjusting the cross-sectional area of the filter medium in the direction perpendicular to air flow direction. The surface area of activated charcoal per unit cross-sectional area is calculated on the basis of the filter material to which the activated charcoal is added. When the filter segment is formed by multiple filter media, the calculation above is based on the cross-sectional area and length of only the filter medium to which the activated charcoal is added.
Examples of activated charcoal which may be cited include those comprising wood, bamboo, coconut shell, walnut shell, or coal, etc. as a starting material. Furthermore, activated charcoal having a BET specific area of 1100 m²/g-1600 m²/g may be used, activated charcoal having a BET specific surface area of 1200 m²/g-1500 m²/g may preferably be used, and activated charcoal having a BET specific surface area of 1250 m²/g-1380 m²/g may more preferably be used. The BET specific surface area may be determined by the nitrogen gas adsorption method (BET multipoint method). Furthermore, activated charcoal having a pore volume of 400 µL/g-800 µL/g may be used, activated charcoal having a pore volume of 500 µL/g-750 µL/g may preferably be used, and activated charcoal having a pore volume of 600 µL/g-700 µL/g may more preferably be used. The pore volume may be calculated from a maximum adsorption amount obtained using the nitrogen gas adsorption method. The amount of activated charcoal which is added per unit length, in the air flow direction, of the filter medium to which the activated charcoal has been added, is preferably 5 mg/cm-50 mg/cm, more preferably 8 mg/cm-40 mg/cm, and even more preferably 10 mg/cm-35 mg/cm. The surface area of the activated charcoal per unit cross-sectional area may be adjusted to the desired value as a result of the specific surface area of the activated charcoal and the amount of activated charcoal added being in the ranges above.
Furthermore, the cumulative 10 vol% particle size (particle size D10) of activated charcoal particles is preferably 250 µm-1200 µm. Furthermore, the cumulative 50 vol% particle size (particle size D50) of activated charcoal particles is preferably 350 µm-1500 µm. It should be noted that the particle sizes D10 and D50 are measured by means of a laser diffraction scattering method. Apparatuses suitable for this measurement that may be cited include the "LA-950" laser diffraction/scattering particle size distribution measurement apparatus produced by HORIBA, Ltd. A powder is poured into cells of the apparatus together with pure water, and the particle size is detected on the basis of light scattering information of the particles. The measurement conditions used in this measurement apparatus are as follows.

Measurement mode: manual flow mode-type cell measurement
Dispersion medium: ion exchange water
Dispersion method: measurement after 1 minute of ultrasound irradiation
Refractive index: 1.92-0.00i (sample refraction)/1.33-0.00i (dispersion medium refractive index)
Number of measurements: two measurements with different samples

Furthermore, there is no particular restriction on the method of adding the activated charcoal to the filter medium of the filter segment, and the activated charcoal should be added so as to be roughly uniformly dispersed in the filter medium to which the activated charcoal is added.

Tipping paper

There is no particular restriction on the material of the tipping paper 33, and it is possible to employ paper made of common vegetable fibers (pulp), a sheet made from polymer-based (polypropylene, polyethylene, nylon, etc.) chemical fibers, a polymer-based sheet, metal foil, or a composite material combining the above. For example, the tipping paper 33 may be fabricated from a composite material in which a polymer-based sheet is laminated onto a paper substrate. It should be noted that the tipping paper 33 referred to here means a sheet-like material that connects a plurality of segments of the tobacco stick 30, such as, for example, linking the tobacco filling portion 31 and the mouthpiece portion 32.
There is no particular restriction on the basis weight of the tipping paper 33, but it is normally 32 gsm-40 gsm, preferably 33 gsm-39 gsm, and more preferably 34 gsm-38 gsm, for example. There is no particular restriction on the air permeability of the tipping paper 33, and it is normally 0 CORESTA units-30,000 CORESTA units, and preferably greater than 0 CORESTA units and no greater than 10,000 CORESTA units. The air permeability is a value measured in accordance with ISO 2965:2009, and, when a differential pressure of both surfaces of the paper is 1 kPa, the air permeability is expressed by a flow rate (cm³) of a gas passing through a surface area of 1 cm² in 1 minute 1 CORESTA unit (1 C.U.) constitutes cm³/(min·cm²) under 1 kPa.
The tipping paper 33 may contain a loading material in addition to the above-described pulp, examples of which can include metal carbonates such as calcium carbonate and magnesium carbonate, metal oxides such as titanium oxide, titanium dioxide and aluminum oxide, metal sulfates such as barium sulfate and calcium sulfate, metal sulfides such as zinc sulfide, quartz, kaolin, talc, diatomaceous earth, gypsum and the like, and calcium carbonate is preferably included in particular from the viewpoint of improving whiteness and opacity and increasing the heating rate. Furthermore, these loading materials may be used alone, or two or more may be used in combination.
Various auxiliaries other than the pulp and the loading material may also be added to the tipping paper 33, for example the paper may comprise a water-resistance improving agent to improve water resistance. A water-resistance improving agent contains a wet-strength agent (WS agent) and a sizing agent. Examples of wet strength agents include urea formaldehyde resins, melamine formaldehyde resins, polyamide epichlorohydrin (PAE), and the like. Furthermore, examples of sizing agents include rosin soap, alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), and highly saponified polyvinyl alcohol having a saponification degree of 90% or more.
A coating agent may be added to at least one of the two surfaces of the tipping paper 33, namely the front surface and the rear surface. There is no particular restriction on the coating agent, but a coating agent that can form a film on the surface of the paper and reduce the permeability of liquids is preferred.
There is no particular restriction on the method for manufacturing the tipping paper 33, and general methods can be applied, and for example in the case of an embodiment in which pulp is the main component, a method that uses pulp can be cited, in which the texture is adjusted and homogenized in a papermaking process employing a Fourdrinier papermaking machine, a cylinder mould papermaking machine, or a round-short combined papermaking machine, etc. It should be noted that, if necessary, a wet strength agent can be added to impart water resistance to a rolling paper, or a sizing agent can be added to adjust a printing condition of the rolling paper.

Microwave shield

The tobacco stick 30 (e.g., the mouthpiece portion 32) may be provided with a microwave shield (electromagnetic wave shield). The microwave shield of the tobacco stick 30 is attached to the cooling segment of the mouthpiece portion 32 upstream of the ventilation holes, and is positioned inside the guide portion 13 of the inhaler 10 when the tobacco stick 30 is inserted in the inhaler 10. As a result, the microwave shield of the tobacco stick 30 collaborates with the guide portion 13 of the inhaler 10 so that it is possible to avoid leakage of microwaves to outside of the inhaler 10. However, provided that the microwave shield is configured to be positioned inside the guide portion 13 of the inhaler 10 when the tobacco stick 30 is inserted in the inhaler 10, it is equally possible for the microwave shield of the tobacco stick 30 to be attached to the filter segment of the mouthpiece portion 32, or to be arranged adjacent to the filter segment of the mouthpiece portion 32, for example. Furthermore, the microwave shield of the tobacco stick 30 may be arranged at an upstream or downstream end portion of a separate filter segment provided adjacent to the cooling segment of the mouthpiece portion 32. The microwave shield of the tobacco stick 30 may also be configured by arranging a pre-formed shielding member at a predetermined position on the tobacco stick 30, or configured by printing said pre-formed shielding member on the filter segment of the mouthpiece portion 32. It should be noted that a microwave shield need not be provided on the tobacco stick 30 when a mouthpiece 40 comprising a microwave shield 41 is attached to the inhaler 10, as will be described later.
When the aperture ratio of the microwave shield of the tobacco stick 30 is designed to take account of blocking microwaves and airflow resistance, the aperture ratio is 10% or greater, preferably 30% or greater, and more preferably 50% or greater, for example. Furthermore, the aperture ratio is 90% or less, preferably 80% or less, and more preferably 70% or less. Furthermore, with the aperture ratio of the microwave shield of the tobacco stick 30 indicated above, the airflow resistance for the inhaler 10 and the tobacco stick 30 overall is 8 mmH₂O or greater, preferably 10 mmH₂O or greater, and more preferably 12 mmH₂O or greater, and is also 100 mmH₂O or less, preferably 80 mmH₂O or less, and more preferably 60 mmH₂O or less. In this case, it is possible to provide a system which balances suppressing microwave leakage and desirable airflow resistance with a simple device configuration. Note that the airflow resistance is measured in accordance with the ISO standard method (ISO 6565), as indicated above.
Furthermore, the tobacco stick 30 configured in the manner above may also have a configuration in which a portion of the outer surface of the tipping paper 33 is covered by a lip-release material. A lip-release material means a material configured for assisting in easy separation, substantially without adhesion, of contact between the lips and the tipping paper 33 when the user holds mouthpiece portion 32 of the tobacco stick 30 in their mouth. The lip-release material may comprise ethylcellulose or methylcellulose, etc., for example. For example, the outer surface of the tipping paper 33 may be coated with a lip-release material by applying an ethylcellulose-based or methylcellulose-based ink to the outer surface of the tipping paper 33.
The lip-release material on the tipping paper 33 is arranged at least on a predetermined mouthpiece region which is contacted by the user's lips when the user holds the mouthpiece portion 32 in their mouth. Specifically, a lip-release material arrangement region on the outer surface of the tipping paper 33 which is covered by the lip-release material is defined as a region lying between the mouthpiece end of the mouthpiece portion 32 and the ventilation holes.
Furthermore, there is no particular restriction on the airflow resistance in the Z-axis direction per tobacco stick 30 configured in the manner described above, but, from the viewpoint of ease of drawing, it is normally 8 mmH₂O or greater, preferably 10 mmH₂O or greater, and more preferably 12 mmH₂O or greater, and is also normally 100 mmH₂O or less, preferably 80 mmH₂O or less, and more preferably 60 mmH₂O or less. The airflow resistance is measured by using a filter airflow resistance measurement instrument produced by Cerulean, for example, in accordance with the ISO standard method (ISO6565:2015). The airflow resistance denotes an air pressure difference between one end face (a first end face) and another end face (a second end face) when air at a predetermined air flow rate (17.5 cc/min) flows from the first end face to the second end face in a state in which air does not pass through the side face of the tobacco stick 30. The units are generally expressed in mmH₂O. The relationship between airflow resistance and the tobacco stick 30 is known to be a proportional relationship in a normal length range (a length of 5-200 mm), and the airflow resistance of the tobacco stick 30 also doubles when the length doubles.
The rod-shaped tobacco stick 30 preferably has a columnar shape satisfying a shape in which the aspect ratio as defined below is 1 or greater. $Aspect ratio = h / w$
w is the width of the tip end of the tobacco stick 30, and h is the length in the Z-axis direction, and preferably h≥w. There is no particular restriction on the transverse-sectional shape of the tobacco stick 30, and it may be polygonal, rounded polygonal, circular, or elliptical, etc. The width w of the tobacco stick 30 is the diameter when the transverse-sectional shape of the tobacco stick 30 is circular, is the major axis when the shape is elliptical, is the diameter of the circumscribing circle when the shape is polygonal, or is the major axis of the circumscribing ellipse when the shape is a rounded polygon. There is no particular restriction on the Z-axis direction length h of the tobacco stick 30, and it is normally 40 mm or greater, preferably 45 mm or greater, and more preferably 50 mm or greater, for example. Furthermore, the Z-axis direction length h is normally 100 mm or less, preferably 90 mm or less, and more preferably 80 mm or less. There is no particular restriction on the width w of the tip end of the tobacco stick 30, and it is normally 5 mm or greater, and preferably 5.5 mm or greater, for example. Furthermore, the width w is normally 10 mm or less, preferably 9 mm or less, and more preferably 8 mm or less. There is no particular restriction on a ratio (cooling segment : filter segment) between the lengths of the cooling segment and the filter segment of the mouthpiece portion 32, in the length of the tobacco stick 30, but from the viewpoint of the amount of flavoring material delivered and the appropriate aerosol temperature, this ratio is normally 0.60-1.40:0.60-1.40, preferably 0.80-1.20:0.80-1.20, more preferably 0.85-1.15:0.85-1.15, even more preferably 0.90-1.10:0.90-1.10, and particularly preferably 0.95-1.05:0.95-1.05. By setting the ratio of the lengths of the cooling segment and the filter segment of the mouthpiece portion 32 within the above ranges, a balance is achieved between the cooling effect, the effect of suppressing losses due to adhesion of the generated vapor and aerosol to the inner wall of the cooling segment, and the function of the filter in adjusting the volume of air and the flavor, thereby making it possible to achieve a good flavor and intensity of flavor.

Configuration of inhaler

The inhaler 10 comprises a case 11 in which various components to be described below are mounted. The case 11 is provided with: an accommodating portion 12 capable of accommodating a portion of the tobacco stick 30 which has been inserted from an opening portion 12a; a guide portion 13 for guiding insertion of the tobacco stick 30 from the opening portion 12a of the accommodating portion 12; and an air flow path 14 which communicates with the accommodating portion 12 and allows air to be introduced into the accommodating portion 12. The accommodating portion 12 is enclosed by a shielding member comprising a metal or the like which blocks microwaves (electromagnetic waves) in order to confine the microwaves to the inside of the accommodating portion 12. The air flow path 14 has an air intake port 14a provided on the exterior of the case 11, and is provided so as to introduce air into the accommodating portion 12 from the air intake port 14a. The air flow path 14 may be provided with a microwave shield 14b which allows the air to pass while blocking microwaves. The air flow path 14 is not limited to being provided on the bottom face of the accommodating portion 12 as shown in fig. 1, and it may equally be provided on a side face or an upper face of the accommodating portion 12.
The inhaler 10 further comprises: a high-frequency oscillation unit 20, a control unit 21, a power source unit 22, a notification unit 23, a communication unit 24, and an object detector 25. These components 20-25 are mounted inside the case 11.
The high-frequency oscillation unit 20 comprises a semiconductor (solid-state) oscillator and generates a high-frequency electromagnetic field (electromagnetic waves) having a predetermined frequency. The semiconductor oscillator is configured by a semiconductor element such as, for example, an LDMOS transistor, a GaAs FET, an SiC MESFET, or a GaN HFET. A high-frequency electromagnetic field (electromagnetic waves) means an electromagnetic field between 3 Hz and 3 THz, including microwaves between 300 MHz and 300 GHz. The high-frequency oscillation unit 20 is capable of generating microwaves having a frequency (e.g., 2.40-2.50 GHz) suitable for heating the tobacco stick 30 (aerosol source). In this embodiment, the high-frequency oscillation unit 20 generates microwaves with a frequency of 2.45 GHz. Furthermore, the high-frequency oscillation unit 20 may comprise an amplifier for amplifying the high-frequency electromagnetic field. In the high-frequency oscillation unit 20, the semiconductor oscillator itself may have the function of an amplifier, or else an amplifier configured as an electronic component separate to the semiconductor oscillator may be provided.
It should be noted that the device for generating the high-frequency electromagnetic field may also be a magnetron oscillator, but using a semiconductor oscillator as the high-frequency oscillation unit 20 allows for a more compact body as compared to when a magnetron oscillator is used. Furthermore, a semiconductor oscillator can operate at a lower voltage than a magnetron oscillator, therefore enabling better frequency stability and output stability. However, the high-frequency oscillation unit 20 of this embodiment only needs to be capable of generating a high-frequency electromagnetic field of a predetermined frequency, and may therefore also be a magnetron oscillator.
The microwaves generated by the high-frequency oscillation unit 20 are supplied to a transmission path 53 provided in the accommodating portion 12, and are emitted into the accommodating portion 12 from an antenna 54 provided at a tip end portion of the transmission path 53. In this embodiment, the transmission path 53 is configured as a microstrip line, and the antenna 54 is configured as a microstrip antenna. A specific configuration example of the transmission path 53 and the antenna 54 will be described below. It should be noted that the transmission path 53 may also be denoted below as the "microstrip line 53".
An isolator for absorbing reflected waves returning to the high-frequency oscillation unit 20 via the microstrip line 53 is provided on the microstrip line 53 or between the microstrip line 53 and the high-frequency oscillation unit 20 in order to protect the high-frequency oscillation unit 20. Furthermore, the high-frequency oscillation unit 20 may also be provided with: a power monitor for detecting the power of output waves output from the high-frequency oscillation unit 20 to the microstrip line 53 and the power of reflected waves falling incident on the high-frequency oscillation unit 20 from the microstrip line 53; and/or an impedance matching unit for matching an impedance on the high-frequency oscillation unit 20 side with an impedance on the microstrip line 53 side to reduce the power of reflected waves.
The control unit 21 functions as an arithmetic processing device and a control device, and controls overall operation of the inhaler 10 in accordance with various programs. Specifically, the control unit 21 may control the high-frequency oscillation unit 20 20 to emit microwaves from the antenna 54 in accordance with a user atomization request, and thereby heat the tobacco stick 30. Furthermore, the control unit 21 may control the high-frequency oscillation unit 20 so that the tobacco stick 30 is heated in accordance with a desired preset heating profile. Furthermore, when a plurality of antennas 54 are arranged along the direction of insertion of the tobacco stick 30 (the -Z direction), the power of the microwaves emitted from each of the antennas 54 may be individually controlled so that a desired heating distribution (temperature distribution) is formed in the tobacco stick 30 in the Z direction. The control unit 21 may be realized by a CPU (central processing unit) or an electronic circuit such as a microprocessor, for example.
The power source unit 22 supplies power to the high-frequency oscillation unit 20 based on control afforded by the control unit 21. The power source unit 22 is configured by a rechargeable battery such as a lithium ion secondary battery, for example. Providing a power source unit 22 such as this enables the inhaler 10 to be portable.
The notification unit 23 notifies the user of information based on control afforded by the control unit 21. Information notified to the user which may be cited includes, for example: information indicating detection of insertion of the tobacco stick 30 into the accommodating portion 12; information indicating the start of microwave heating of the tobacco stick 30; information indicating a transition to an aerosol inhalation-possible state; error information; and remaining capacity information of the power source unit 22 (battery remaining capacity information), etc. The notification unit 23 may be configured by a light-emitting element such as an LED (light-emitting diode), a vibrating element such as a vibration motor, or a sound output element. The notification unit 23 may be configured by display element (display) such as an LCD (liquid crystal display). The notification unit 23 may be a combination of two or more elements among a light-emitting element, a vibrating element, a sound output element, and a display element.
The communication unit 24 is an interface for acquiring information relating to a state of use of the inhaler 10 and sending this information to an external data server or a user mobile terminal device, etc. (referred to below as a data server, etc.), and for receiving data from the data server, etc. The communication unit 24 can communicate with the data server, etc., via short-range wireless communication such as Bluetooth (registered trademark) or long-range wireless communication such as LPWA (Low Power Wide Area). Note that communication between the communication unit 24 and the data server, etc., is not limited to the wireless communication mentioned above and may equally be another form of wireless communication or else wired communication.
The object detector 25 detects whether or not the tobacco stick 30 is inside the accommodating portion 12. By this means, the control unit 21 is able to determine whether or not there is a state in which the tobacco stick 30 is inserted (accommodated) inside the accommodating portion 12, based on a detection result from the object detector 25, and can control microwave emission from the antenna 54 in accordance with the result of this determination. For example, when the control unit 21 has determined a state in which the tobacco stick 30 is not accommodated inside the accommodating portion 12, based on the detection result from the object detector 25, the control unit 21 prohibits microwave emission from the antenna 54. Meanwhile, when the control unit 21 has determined a state in which the tobacco stick 30 is inserted (accommodated) inside the accommodating portion 12, based on the detection result from the object detector 25, the control unit 21 enables microwave emission from the antenna 54. The object detector 25 may be configured by a capacitive proximity sensor, but this is not limiting, and it may equally be configured by a contact sensor (e.g., a pressure sensor) or a photoelectric sensor, etc. It should be noted that in the example of fig. 1, the object detector 25 is provided on the bottom face (the inner face on the -Z direction side) of the accommodating portion 12, but may equally be provided on the side face or upper face of the accommodating portion 12, or on the guide portion 13.
Furthermore, the mouthpiece 40, which the user holds in their mouth in order to draw in vapor (aerosol-containing vapor) from the accommodating portion 12, may be attached to the inhaler 10 of this embodiment, as shown in fig. 1 and 2. The mouthpiece 40 may be attached to the guide portion 13 of the inhaler 10 so as to cover a part (mouthpiece portion 32) of the tobacco stick 30 protruding from the inhaler 10 (accommodating portion 12). The mouthpiece 40 is then provided with a microwave shield 41 for blocking leakage of microwaves to the outside from the accommodating portion 12 through the opening portion 12a and the guide portion 13. The microwave shield 41 may be configured by a metal mesh, etc. so that vapor is allowed to pass while microwaves are blocked.
When the mouthpiece 40 comprising the microwave shield 41 is used, the inhaler 10 may be provided with the mouthpiece detector 26 for detecting whether or not the mouthpiece 40 is attached. This allows the control unit 21 to control emission of microwaves from the antenna 54 on the basis of a detection result from the mouthpiece detector 26. For example, when the control unit 21 has determined that the mouthpiece 40 is not attached, based on the detection result from the mouthpiece detector 26, the control unit 21 prohibits microwave emission from the antenna 54. Meanwhile, when the control unit 21 has determined that the mouthpiece 40 is attached, based on the detection result from the mouthpiece detector 26, the control unit 21 enables microwave emission from the antenna 54. Note that the inhaler 10 may be configured so that the user holds the mouthpiece portion 32 of the tobacco stick 30 directly in their mouth, without the use of the mouthpiece 40. In this case, a microwave shield which is configured by a metal mesh, etc. may be provided on the tobacco stick 30 (e.g., on the mouthpiece portion 32) in order to block microwaves.
A specific configuration example of the microstrip line 53 and the antenna 54 will be described next. The microstrip line 53 and the antenna 54 are arranged (formed) on a dielectric substrate 51 disposed inside the accommodating portion 12. Specifically, as shown in fig. 2, the dielectric substrate 51 comprises: a first face 51a facing an outer circumferential surface of the tobacco stick 30 inserted inside the accommodating portion 12; and a second face 51b which is the face on the opposite side to the first face 51a. The microstrip line 53 and the antenna 54 are arranged (formed) on the first face 51a of the dielectric substrate 51. Furthermore, a ground layer 52 formed by a metal, etc. is arranged (formed) on the second face 51b of the dielectric substrate 51. Any substrate, such as a glass substrate or a sapphire substrate for example, may be used as the dielectric substrate 51, but a dielectric substrate having high permittivity should be used from the perspective of making the microstrip line 53 and the antenna 54 compact. Furthermore, a dielectric substrate having low dielectric loss should be used from the perspective of reducing microwave transmission loss.
Fig. 3A shows a configuration example of the microstrip line 53 and the antenna 54 on the first face 51a of the dielectric substrate 51. The "θ direction" in fig. 3A denotes the circumferential direction (circumferential direction about the Z axis) of the tobacco stick 30 inserted in the inhaler 10, as mentioned above, and the width W_L of the microstrip line 53 and the width W_A of the antenna 54 represent lengths in the θ direction. As shown in fig. 3A, the width W_A of the antenna 54 is formed to be greater than the width W_L of the microstrip line 53. For example, in order for the microwaves transmitted by the microstrip line 53 to be efficiently emitted from the antenna 54, the width W_A of the antenna 54 should be close to 1/2 or close to 1/4 of the wavelength of the microwaves transmitted by the microstrip line 53, and should be at least four times the width W_L of the microstrip line 53. The antenna 54 has a square shape in the example of fig. 3A, but this is not limiting, and it may equally have a rectangular (oblong) shape or a circular shape. Furthermore, at its connection with the microstrip line 53, the antenna 54 may comprise cutouts 54a for matching impedances of the microstrip line 53 and the antenna 54, as shown in fig. 3B.
Here, the first face 51a of the dielectric substrate 51 may constitute at least a portion of the inner wall of a cavity into which the tobacco stick is inserted. The cavity is the part of the accommodating portion 12 into which the tobacco stick 30 is inserted. In this embodiment, the dielectric substrate 51 may be configured as a cylindrical member surrounding the entirety of the outer circumferential surface of the tobacco stick 30, but this is not limiting, and it may equally be configured to partially surround the outer circumferential surface of the tobacco stick 30 (i.e., to face this outer circumferential surface in part). Furthermore, the dielectric substrate 51 may be configured so that the first face 51a contacts the tobacco stick 30. In this case, the dielectric substrate 51 may itself function as a support member for supporting (holding) the tobacco stick 30. Meanwhile, the dielectric substrate 51 may be configured so that the first face 51a is spaced apart from the tobacco stick 30. In this case, a support member for supporting (holding) the tobacco stick 30 may be provided inside the accommodating portion 12 (cavity) separately from the dielectric substrate 51.
Furthermore, the ground layer 52 provided on the second face 51b of the dielectric substrate 51 is covered by the case 11 constituting the exterior of the aerosol-generating device 10 in the example of fig. 1 and 2, but this is not limiting, and at least a portion of the ground layer 52 may be exposed to the outside. That is to say, the ground layer 52 may itself constitute at least a portion of the exterior of the aerosol-generating device 10. By virtue of this configuration, the case 11 need not be provided around the ground layer 52, which may therefore be advantageous in making the aerosol-generating device 10 compact and in reducing device costs.
In a configuration employing the microstrip line 53 and the antenna 54 in this way, a portion of the tobacco stick 30 inserted in the inhaler 10 is irradiated with the microwaves emitted from the antenna 54. That is to say, the tobacco stick 30 can be partially irradiated with the microwaves emitted from the antenna 54, and the tobacco stick 30 can be partially heated. A desired heating distribution can therefore be formed in the tobacco stick 30 by arranging a plurality of sets (groups) including the microstrip line 53 and the antenna 54 in the inhaler 10. Examples in which a plurality of sets including the microstrip line 53 and the antenna 54 are provided will be described below. It should be noted that sets including the microstrip line 53 and the antenna 54 may be designated below as "antenna sets AS".

EXAMPLE 1

Fig. 4 shows an arrangement of a plurality of antenna sets AS of Example 1. Fig. 4 shows a view in cross section of the dielectric substrate 51 and the ground layer 52. In the example of fig. 4, the dielectric substrate 51 and the ground layer 52 are configured as cylindrical members, and the tobacco stick 30 may be inserted on the inside of the dielectric substrate 51 which is configured as a cylindrical member.
In the example of fig. 4, a plurality of (three) antenna sets AS1-AS3 (first set) are provided on the first face 51a (inside face) of the dielectric substrate 51. Each of the plurality of antenna sets AS1-AS3 may include: a microstrip line 53 (first microstrip line) extending along the Z direction, and an antenna 54 (first antenna) connected to the end portion of the microstrip line 53. Specifically, the antenna set AS1 includes a microstrip line 53a and an antenna 54a. The antenna set AS2 includes a microstrip line 53b and an antenna 54b. The antenna set AS3 includes a microstrip line 53c and an antenna 54c.
Furthermore, the plurality of antenna sets AS1-AS3 are arranged spaced apart so that the respective antennas 54 are offset from each other in the Z direction and the θ direction. Specifically, the antenna 54b of the antenna set AS2 is arranged at a position offset in the Z direction and the θ direction from the antenna 54a of the antenna set AS1. Similarly, the antenna 54c of the antenna set AS3 is arranged at a position offset in the Z direction and the θ direction from the antenna 54b of the antenna set AS2.
The antennas 54a-54c of the antenna sets AS1-AS3 of Example 1 are thus arranged at offsets in the Z direction and the θ direction. This enables microwave emission from each of the antennas 54a-54c to be individually controlled so that the desired heating distribution in the Z direction can be formed in the tobacco stick 30.
Here, the amount of offset of the antennas 54a-54c in the θ direction may be set by using experimentation or simulation, etc. so that the effects of microwaves on the antennas 54a-54c can be kept below a threshold. Furthermore, the amount of offset of the antennas 54a-54c in the Z direction may be freely set according to the heating distribution to be formed in the tobacco stick 30. For example, if the heating distribution is to be controlled with high precision (high resolution), the amount of offset in the Z direction should be reduced to increase the density of antennas 54 in the Z direction. As an example, the antennas 54a-54c should be arranged so that those among the antennas 54a-54c which are adjacent in the θ direction partially overlap in the Z direction, as shown in fig. 5. An overlap amount OA of the antennas in the Z direction should be no greater than half (preferably no greater than 1/4) of the Z-direction length of each antenna, from the perspective of irradiating different parts of the tobacco stick 30 with the microwaves emitted from each antenna, for example. The overlap amount OA may be the same among the plurality of antennas 54a-54c, but may be different among the plurality of antennas 54a-54c if there is a part of the tobacco stick 30 which is to be irradiated with microwaves in a focused manner.

EXAMPLE 2

Fig. 6 shows an arrangement of a plurality of antenna sets AS of Example 2. Fig. 6 shows a view in cross section of the dielectric substrate 51 and the ground layer 52, similarly to fig. 4. In the example of fig. 6, the dielectric substrate 51 and the ground layer 52 are configured as cylindrical members, and the tobacco stick 30 may be inserted on the inside of the dielectric substrate 51 which is configured as a cylindrical member. Note that any matters not mentioned in Example 2 may be in accordance with Example 1.
In the example of fig. 6, a plurality of (three) first antenna sets AS4-AS6 (first sets), and a plurality of (two) second antenna sets AS7-AS8 (second sets) are provided on the first face (inside face) of the dielectric substrate 51.
Each of the plurality of first antenna sets AS4-AS6 may include: a microstrip line 53 (first microstrip line) extending along the Z direction, and an antenna 54 (first antenna) connected to the end portion of the microstrip line 53. Specifically, the first antenna set AS4 includes a microstrip line 53d and an antenna 54d. The first antenna set AS5 includes a microstrip line 53e and an antenna 54e. The first antenna set AS6 includes a microstrip line 53f and an antenna 54f.
The plurality of first antenna sets AS4-AS6 are arranged spaced apart so that the respective antennas 54 are offset from each other in the θ direction. Specifically, the antenna 54e of the antenna set AS5 is arranged at a position offset in the θ direction from the antenna 54d of the antenna set AS4. Similarly, the antenna 54f of the antenna set AS6 is arranged at a position offset in the θ direction from the antenna 54e of the antenna set AS5. It should be noted that the antennas 54d-54f have the same Z-direction positions in the first antenna sets AS4-AS6.
Furthermore, each of the plurality of second antenna sets AS7-AS8 may include: a microstrip line 53 (second microstrip line) extending along the Z direction, and an antenna 54 (second antenna) connected to the end portion of the microstrip line 53. Specifically, the second antenna set AS7 includes a microstrip line 53g and an antenna 54g. The second antenna set AS8 includes a microstrip line 53h and an antenna 54h.
The plurality of second antenna sets AS7-AS8 are arranged spaced apart so that the respective antennas 54 are offset from each other in the θ direction. Specifically, the antenna 54h of the antenna set AS8 is arranged at a position offset in the θ direction from the antenna 54d of the antenna set AS4. It should be noted that the antennas 54g-54h have the same Z-direction positions in the second antenna sets AS7-AS8.
Furthermore, the antennas 54g-54h in the plurality of second antenna sets AS7-AS8 are arranged spaced apart so as to be offset in the Z direction from the antennas 54d-54f of the plurality of first antenna sets AS5-AS6. The antennas 54g-54h of each of the second antenna sets AS7-AS8 are then arranged between the microstrip lines 53d-53f of the plurality of first antenna sets AS5-AS6. Specifically, the antenna 54g of the second antenna set AS7 is arranged between the microstrip line 53d of the first antenna set AS4 and the microstrip line 53e of the first antenna set AS5, in the θ direction. The antenna 54h of the second antenna set AS8 is arranged between the microstrip line 53e of the first antenna set AS5 and the microstrip line 53f of the first antenna set AS6, in the θ direction.
The arrangement of antenna sets AS4-AS8 in Example 2 described above also enables microwave emission from each of the antennas 54d-54h to be individually controlled so that the desired heating distribution in the Z direction can be formed in the tobacco stick 30.

Other Embodiments

In the configuration examples described above, the microstrip line 53 and the antenna 54 may be damaged by contact with the tobacco stick 30 when the tobacco stick 30 is inserted into the inhaler 10. A protective film should therefore be provided on the first face 51a (e.g., the inside face) of the dielectric substrate 51 so as to cover the microstrip line 53 and the antenna 54. A thin film such as a silicon dioxide film (SiO₂) or a silicon nitride film (SiN) may be used as a protective film, for example.
The invention is not limited to the embodiments described above and may be modified or altered in various ways within the scope of the essential point of the invention.

Claims

An aerosol-generating device into which an aerosol-generating article comprising an aerosol source is inserted, the aerosol-generating device being characterized by comprising:
a dielectric substrate having a first face facing the aerosol-generating article inserted in the aerosol-generating device, and a second face on the opposite side to the first face;

a first antenna arranged on the first face of the dielectric substrate so as to emit electromagnetic waves toward a portion of the aerosol-generating article;

a first microstrip line arranged on the first face of the dielectric substrate so as to transmit the electromagnetic waves to the first antenna; and

a ground layer formed on the second face of the dielectric substrate.
The aerosol-generating device as claimed in claim 1, characterized in that the ground layer constitutes at least a portion of the exterior of the aerosol-generating device.
The aerosol-generating device as claimed in claim 1 or 2, characterized in that the first face of the dielectric substrate constitutes at least a portion of an inner wall of a cavity into which the aerosol-generating article is inserted.
The aerosol-generating device as claimed in any one of claims 1 to 3, characterized by further comprising a protective film covering the first antenna and the first microstrip line.
The aerosol-generating device as claimed in any one of claims 1 to 4, characterized in that the first microstrip line is arranged on the first face so as to extend along a direction of insertion of the aerosol-generating article.
The aerosol-generating device as claimed in any one of claims 1 to 5, characterized in that a plurality of first sets including the first antenna and the first microstrip line are arranged along a circumferential direction of the aerosol-generating article inserted in the aerosol-generating device.
The aerosol-generating device as claimed in claim 6, characterized in that the plurality of first sets are arranged so that the respective first antennas are offset from each other in the direction of insertion of the aerosol-generating article.
The aerosol-generating device as claimed in any one of claims 1 to 6, further comprising: a second antenna arranged on the first face of the dielectric substrate so as to emit electromagnetic waves toward a portion of the aerosol-generating article; and
a second microstrip line arranged on the first face of the dielectric substrate so as to transmit the electromagnetic waves to the second antenna;

characterized in that

the first antenna and the second antenna are arranged at positions offset from each other in the direction of insertion of the aerosol-generating article and in a circumferential direction of the aerosol-generating article inserted in the aerosol-generating device.
The aerosol-generating device as claimed in claim 8, characterized in that the first microstrip line and the second microstrip line are each arranged on the first face so as to extend along the insertion direction.
The aerosol-generating device as claimed in claim 9, characterized in that a plurality of first sets including the first antenna and the first microstrip line are arranged along the circumferential direction, and
the second antenna is arranged between the first microstrip lines of the plurality of first sets in the circumferential direction.