Patent Description:
A common combustion smoking article (cigarette) for smoking through combustion includes a tobacco-containing segment, in which a tobacco filler of dry tobacco leaves shredded into a width of about <NUM> and added with a flavor, a humectant, an appropriate amount of moisture, and so forth is wrapped cylindrically in a paper wrapper; and a mouthpiece segment, in which a corrugated paper or fibers of cellulose acetate or the like are wrapped cylindrically in a paper wrapper. The tobacco-containing segment and the mouthpiece segment are connected with a lining paper. A user smokes by igniting the end of the tobacco-containing segment with a lighter or the like and inhaling from the end of the mouthpiece segment. The leading end of the tobacco-containing segment burns at a temperature exceeding <NUM>.

As a substitute for such a common combustion smoking article, a heat-not-burn smoking article and a heat-not-burn smoking system, which utilize heating in place of combustion, have been developed (Patent Literature (PTL) <NUM> to <NUM>, for example). The heating temperature is lower than the burning temperature in a combustion smoking article and is <NUM> or lower, for example. In a heat-not-burn smoking article, a tobacco filler of a tobacco-containing segment contains an aerosol former, such as glycerol, propylene glycol (PG), triethyl citrate (TEC), or triacetin. Such an aerosol former is vaporized upon heating, moved to a cooling segment within a mouthpiece segment through inhalation, and cooled to generate an aerosol further reliably. Since the aerosol is inhaled together during inhalation from a filter segment that is provided in the mouth side end within the mouthpiece segment, it is possible to ensure a satisfactory sensation for a user.

A heat-not-burn smoking system typically includes a cylindrical heat-not-burn smoking article having a shape similar to a common combustion smoking article; and a heating device equipped with a battery, a controller, a heater, and so forth. Exemplary heaters include an electric resistance heater and an induction heater. Exemplary heating methods by an electric resistance heater include a method of heating a heat-not-burn smoking article with a heater from the outside and a method of heating by inserting a needle-like or blade-like heater from the leading end of a heat-not-burn smoking article into a tobacco-containing segment that includes a tobacco filler.

PTL <NUM> is concerned with a smoking article for insertion into an apparatus for heating smokable material to volatilize at least one component of the smokable material. The smoking article includes a body of smokable material and a filter assembly. The filter assembly includes a cooling segment having perforations, a filter segment adjacent to the cooling segment and a hollow mouth end segment adjacent to the filter segment.

In <CIT>, a smoking article is described, which comprises a tobacco rod and a filter connected to the tobacco rod. The filter comprises a first filter segment having a ventilation zone with perforations and a hollow tube segment downstream of the first filter segment. The hollow tube segment defines a cavity at the mouth end of the filter. The filter may further comprise a second, rod end filter segment.

As mentioned above, an aerosol former vaporized upon heating (hereinafter, also referred to as "vaporized aerosol component") cools primarily in a cooling segment and condenses from the vapor into particles, thereby forming an aerosol. Here, the vaporized aerosol component needs to be cooled sufficiently to allow inhalation by a user from a filter segment provided in the mouth side end. As a cooling segment for a heat-not-burn smoking article, for example, PTL <NUM> discloses a feature in which perforations are provided on the outer perimeter of a hollow cylindrical part to introduce external air from the perforations during inhalation and to cool a vaporized aerosol component through contact with external air.

However, when a vaporized aerosol component is cooled solely by external air introduced from the perforations that are provided in the cooling segment, a large amount of external air needs to be introduced for sufficient cooling. Consequently, a smoking flavor is destroyed. For this reason, there is a need for developing a method that allows sufficient cooling of a vaporized aerosol component without destroying a smoking flavor.

An object of the present invention is to provide a heat-not-burn smoking article that allows sufficient cooling of a vaporized aerosol component without destroying a smoking flavor and to provide a heat-not-burn smoking system including the heat-not-burn smoking article.

The inventors resolved the above-mentioned problem by limiting, within a specific range, a position at which perforations are provided in a cooling segment. In other words, the problem is resolved by the following present invention, as defined in the appended claims.

According to the present invention, it is possible to provide a heat-not-burn smoking article that allows sufficient cooling of a vaporized aerosol component without destroying a smoking flavor and to provide a heat-not-burn smoking system including the heat-not-burn smoking article.

A heat-not-burn smoking article according to the present invention includes: a tobacco-containing segment containing tobacco and an aerosol former; a tubular cooling segment having one or more perforations on the perimeter; and a tubular member having an inner diameter smaller than the cooling segment, where the cooling segment is joined at the end in the mouth end direction to the member; and the perforations are provided at a position <NUM> to <NUM> from the joined face. The distance is a distance between the center of the perforations and the joined face. <FIG> illustrates the outline of the present invention. In <FIG> is a tobacco-containing segment, <NUM> is a cooling segment, <NUM> is a tubular member having an inner diameter smaller than the cooling segment, <NUM> is a perforation, O is a joined face between the cooling segment <NUM> and the member <NUM>, and t is a distance between the joined face O and the center of the perforation. A vaporized aerosol component generated in the tobacco-containing segment <NUM> is cooled in the cooling segment <NUM> to form an aerosol and introduced into the member <NUM>. On this occasion, the aerosol is further cooled through mixing with air introduced from the perforation <NUM>. Since the inner diameter suddenly decreases downstream of the joined face O in the mouth end direction (hereinafter, also simply referred to as "downstream"), the flow of a mixed stream of the aerosol and air (hereinafter, also simply referred to as "mixed stream") changes. In the present invention, the perforation <NUM> is provided at a specific position from the joined face O. Due to such a perforation <NUM>, it is possible to enhance mixing efficiency of the aerosol and air. In this view, the upper limit of t is <NUM> or less. Meanwhile, when the perforation <NUM> is excessively close to the joined face O, the strength of a heat-not-burn smoking article decreases. In this view, the lower limit of t is <NUM> or more. Accordingly, when t falls within the above-mentioned range, the balance between cooling efficiency and strength can be optimized. Moreover, since excessive air need not be introduced from the perforation <NUM>, the present invention also exerts the effects of enabling efficient cooling of an aerosol without reducing a smoking flavor. In this view, t is preferably <NUM> to <NUM>.

From a viewpoint of suddenly changing the flow of the mixed stream at the joined face O as a boundary, d/D is preferably <NUM> to <NUM> and more preferably <NUM> to <NUM> where d is the inner diameter of the member <NUM> and D is the inner diameter of the cooling segment <NUM>. When d/D falls within these ranges, it is possible to change the flow of the mixed stream from a laminar flow to a turbulent flow at the joined face O as a boundary. The inner diameter d is not limited but is typically and preferably <NUM> to <NUM>.

The heat-not-burn smoking article of the present invention may be provided, downstream of the member <NUM>, with a filter segment or other members. Accordingly, the distance from the mouth end to the center of the perforation <NUM> varies depending on the size of a member to be disposed downstream. In an embodiment, the distance is preferably <NUM> to <NUM>.

The member <NUM> is preferably a center hole segment, and a filter segment is preferably disposed downstream of the member <NUM>. <FIG> illustrates a preferable embodiment of the heat-not-burn smoking article of the present invention.

In <FIG>, <NUM> is a heat-not-burn smoking article, <NUM> is a tobacco-containing segment, and <NUM> is a mouthpiece segment. The mouthpiece segment <NUM> includes a cooling segment <NUM>, a center hole segment <NUM>' as the member, and a filter segment <NUM>. During smoking, the tobacco-containing segment <NUM> is heated and inhalation takes place at the end of the filter segment <NUM>.

The tobacco-containing segment <NUM> includes a tobacco filler <NUM> containing tobacco and an aerosol former; and a tubular wrapper <NUM> that covers the tobacco filler <NUM>. The tobacco filler <NUM> may further contain a volatile flavor component and/or water. The size of tobacco used as a filler or a preparation method therefor is not limited. For example, dry tobacco leaves shredded into a width of <NUM> to <NUM> may be used. In this case, the shreds have a length of about <NUM> to <NUM>. Moreover, those prepared by uniformly pulverizing dry tobacco leaves into an average particle size of about <NUM> to <NUM>, forming into sheets, and shredding the sheets into a width of <NUM> to <NUM> may also be used. In this case, the shreds have a length of about <NUM> to <NUM>. Further, the above-mentioned formed sheets may be gathered without shredding and used as a filler. Furthermore, a plurality of cylindrical sheets may be arranged concentrically. In either case of using dry tobacco leaves as shreds or as sheets formed after uniform pulverization, various types of tobacco may be employed for a tobacco filler. Flue-cured, burley, oriental, and domestic, regardless of Nicotiana tabacum varieties or Nicotiana rustica varieties, may be blended as appropriate for an intended taste and used. The details of the varieties of tobacco are disclosed in "<NPL>.

There are a plurality of conventional methods for pulverizing tobacco and forming into uniform sheets. Such sheets include a sheet made by a papermaking process; a cast sheet made by uniformly mixing with a suitable solvent, such as water, thinly casting the resulting uniform mixture on a metal sheet or a metal sheet belt, and drying; and a rolled sheet formed by extruding a uniform mixture with a suitable solvent, such as water, into a sheet shape. The details of the types of uniform sheets are disclosed in "<NPL>.

The filling density of the tobacco filler <NUM> is not particularly limited but is typically <NUM>/cm<NUM> or more, preferably <NUM>/cm<NUM> or more and typically <NUM>/cm<NUM> or less, preferably <NUM>/cm<NUM> or less from a viewpoint of ensuring the performance of the heat-not-burn smoking article <NUM> and imparting a satisfactory smoking flavor. Specifically, in the case of the tobacco-containing segment <NUM> of <NUM> in circumference and <NUM> in length, the content range of the tobacco filler <NUM> in the tobacco-containing segment <NUM> may be <NUM> to <NUM> and is preferably <NUM> to <NUM> per tobacco-containing segment <NUM>.

The aerosol former is a material that can generate an aerosol upon heating. Examples include, but are not particularly limited to, glycerol, propylene glycol (PG), triethyl citrate (TEC), triacetin, and <NUM>,<NUM>-butanediol. These may be used alone or in combination.

The volatile flavor component is not particularly limited and examples include, from a viewpoint of imparting a satisfactory smoking flavor, acetanisole, acetophenone, acetylpyrazine, <NUM>-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, <NUM>,<NUM>-butanedione, <NUM>-butanol, butyl butyrate, butyric acid, caramel, cardamom oil, carob absolute, β-carotene, carrot juice, L-carvone, β-caryophyllene, cassia bark oil, cedarwood oil, celery seed oil, chamomile oil, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, cinnamyl cinnamate, citronella oil, DL-citronellol, clary sage extract, cocoa, coffee, cognac oil, coriander oil, cuminaldehyde, davana oil, δ-decalactone, γ-decalactone, decanoic acid, dill oil, <NUM>,<NUM>-dimethyl-<NUM>,<NUM>-cyclopentanedione, <NUM>,<NUM>-dimethyl-<NUM>-hydroxy-<NUM>,<NUM>-dihydrofuran-<NUM>-one, <NUM>,<NUM>-dimethyl-<NUM>-octenoic acid, <NUM>,<NUM>-dimethylpyrazine, <NUM>,<NUM>-dimethylpyrazine, <NUM>,<NUM>-dimethylpyrazine, ethyl <NUM>-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, <NUM>-ethyl-<NUM>,(<NUM> or <NUM>)-dimethylpyrazine, <NUM>-ethyl-<NUM>-hydroxy-<NUM>-methyl-<NUM>(<NUM>)-furanone, <NUM>-ethyl-<NUM>-methylpyrazine, eucalyptol, fenugreek absolute, genet absolute, gentian root infusion, geraniol, geranyl acetate, grape juice, guaiacol, guava extract, γ-heptalactone, γ-hexalactone, hexanoic acid, cis-<NUM>-hexen-<NUM>-ol, hexyl acetate, hexyl alcohol, hexyl phenylacetate, honey, <NUM>-hydroxy-<NUM>-pentenoic acid γ-lactone, <NUM>-hydroxy-<NUM>-(<NUM>-hydroxy-<NUM>-butenyl)-<NUM>,<NUM>,<NUM>-trimethyl-<NUM>-cyclohexen-<NUM>-one, <NUM>-(p-hydroxyphenyl)-<NUM>-butanone, <NUM>-hydroxyundecanoic acid sodium salt, immortelle absolute, β-ionone, isoamyl acetate, isoamyl butyrate, isoamyl phenylacetate, isobutyl acetate, isobutyl phenylacetate, jasmine absolute, kola nut tincture, labdanum oil, terpeneless lemon oil, licorice extract, linalool, linalyl acetate, lovage root oil, maltol, maple syrup, menthol, menthone, L-menthyl acetate, p-methoxybenzaldehyde, methyl <NUM>-pyrrolyl ketone, methyl anthranilate, methyl phenylacetate, methyl salicylate, <NUM>'-methylacetophenone, methyl cyclopentenolone, <NUM>-methylvaleric acid, mimosa absolute, molasses, myristic acid, nerol, nerolidol, γ-nonalactone, nutmeg oil, δ-octalactone, octanal, octanoic acid, orange flower oil, orange oil, oris root oil, palmitic acid, ω-pentadecalactone, peppermint oil, petitgrain Paraguay oil, phenethyl alcohol, phenethyl phenylacetate, phenylacetic acid, piperonal, plum extract, propenylguaethol, propyl acetate, <NUM>-propylidenephthalide, 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, <NUM>,<NUM>,<NUM>,<NUM>-tetrahydroquinoxaline, <NUM>,<NUM>,<NUM>,<NUM>-tetramethyl-<NUM>-oxatricyclo[<NUM>. (<NUM>)]tridecane, <NUM>,<NUM>,<NUM>,<NUM>-tetramethylpyrazine, thyme oil, tomato extract, <NUM>-tridecanone, triethyl citrate, <NUM>-(<NUM>,<NUM>,<NUM>-trimethylcyclohex-<NUM>-enyl)but-<NUM>-en-<NUM>-one, <NUM>,<NUM>,<NUM>-trimethylcyclohex-<NUM>-ene-<NUM>,<NUM>-dione, <NUM>-(<NUM>,<NUM>,<NUM>-trimethylcyclohexa-<NUM>,<NUM>-dienyl)but-<NUM>-en-<NUM>-one, <NUM>,<NUM>,<NUM>-trimethylpyrazine, γ-undecalactone, γ-valerolactone, vanilla extract, vanillin, veratraldehyde, violet leaf absolute, and extracts of tobacco plants (tobacco leaf, tobacco stem, tobacco flower, tobacco root, and tobacco seed). Among these, menthol is particularly preferable. These volatile flavor components may be used alone or in combination.

The content of an aerosol former in the tobacco filler <NUM> is not particularly limited but is typically <NUM> to <NUM> mass% and preferably <NUM> to <NUM> mass% from a viewpoint of generating an aerosol sufficiently and imparting a satisfactory smoking flavor. When the tobacco filler <NUM> contains a volatile flavor component, the content of the volatile flavor component in the tobacco filler is not particularly limited but is, from a viewpoint of imparting a satisfactory smoking flavor, typically <NUM>,<NUM> ppm or more, preferably <NUM>,<NUM> ppm or more, more preferably <NUM>,<NUM> ppm or more and typically <NUM>,<NUM> ppm or less, preferably <NUM>,<NUM> ppm or less, and more preferably <NUM>,<NUM> ppm or less based on the mass of the tobacco filler.

A method of packing the tobacco filler <NUM> within the wrapper <NUM> is not particularly limited. For example, the tobacco filler <NUM> may be wrapped in the wrapper <NUM> or the tubular wrapper <NUM> may be filled with the tobacco filler <NUM>. When the shape of tobacco has a longitudinal direction as in a rectangle, tobacco may be packed with the longitudinal direction randomly aligned within the wrapper <NUM> or may be packed with the longitudinal direction aligned with the axial direction or the direction perpendicular to the axial direction of the tobacco-containing segment <NUM>. A tobacco component, an aerosol former, and water contained in the tobacco filler <NUM> are vaporized by heating the tobacco-containing segment <NUM> and moved to the mouthpiece segment <NUM> through inhalation.

The cooling segment <NUM> comprises a tubular member <NUM>. The tubular member <NUM> may be a paper tube of cylindrically processed cardboard, for example. The tubular member <NUM> and a mouthpiece lining paper <NUM> described hereinafter are provided with a perforation <NUM> passing therethrough. Through the perforation <NUM>, air is introduced into the cooling segment <NUM> from the outside during inhalation. Consequently, a vaporized aerosol component generated through heating of the tobacco-containing segment <NUM> comes into contact with external air and liquefies due to the lowering temperature, thereby forming an aerosol. The size (diameter) of the perforation <NUM> is not particularly limited and may be <NUM> to <NUM>, for example. The number of the perforation <NUM> is also not particularly limited and may be one or two or more. For example, a plurality of perforations <NUM> may be provided on the perimeter of the cooling segment <NUM>. The amount of external air introduced from the perforation(s) <NUM> is preferably <NUM> volume% or less and more preferably <NUM> volume% or less based on the total volume of gas inhaled by a user. The lower limit is preferably <NUM> volume% or more and more preferably <NUM> volume% or more. When the proportion of the external air falls within these ranges, it is possible to satisfactorily suppress reduction in smoking flavor due to dilution with external air.

The center hole segment comprises a filling layer having a hollow portion and an inner plug wrapper that covers the filling layer. For example, the center hole segment <NUM>' comprises a first filling layer <NUM> having a hollow portion and a first inner plug wrapper <NUM> that covers the first filling layer <NUM>. The center hole segment <NUM>' also acts to increase the strength of the mouthpiece segment <NUM>. The first filling layer <NUM> may be, for example, a hollow rod formed by hardening highly densely packed cellulose acetate fibers added with <NUM> to <NUM> mass%, based on the mass of cellulose acetate, of a plasticizer including triacetin. Since the first filling layer <NUM> has a high filling density of fibers, air and an aerosol flow only through the hollow portion and hardly flow within the first filling layer <NUM> during inhalation. Since the first filling layer <NUM> inside the center hole segment <NUM>' is a fiber-filled layer, a user rarely feels odd by touch from the outside during use. The center hole segment <NUM>' is preferably wrapped further in an outer plug wrapper <NUM>. As illustrated in <FIG>, the outer plug wrapper <NUM> may be wrapped around the center hole segment <NUM>' and the filter segment <NUM> simultaneously.

The configuration of a filter segment in the present invention is not particularly limited. For example, as the filter segment <NUM> in <FIG>, a filter segment comprises a second filling layer <NUM> and a second inner plug wrapper <NUM> that covers the second filling layer <NUM>. Since the second filling layer <NUM> is present all the way up to the mouth end in the filter segment <NUM>, the end has an appearance similar to a common combustion smoking article. At least either the inner plug wrapper <NUM> or the outer plug wrapper14 is preferably a paper having a basis weight of <NUM>/m<NUM> or more and a thickness of <NUM> or more. Such paper exhibits satisfactory thermal insulation due to the relatively high basis weight and large thickness. Consequently, a smoker feels a temperature further suitable for smoking by the lips during smoking. In this view, both the inner plug wrapper and the outer plug wrapper are preferably made of the above-mentioned paper. The basis weight is more preferably <NUM>/m<NUM> or more. Meanwhile, the upper limit is not limited but is preferably <NUM>/m<NUM> or less and more preferably <NUM>/m<NUM> or less. The thickness is more preferably <NUM> or more. Meanwhile, the upper limit is not limited but is preferably <NUM> or less and more preferably <NUM> or less. When the basis weight and the thickness fall within these ranges, the manufacture of a heat-not-burn smoking article also becomes easy. To further enhance thermal insulation efficiency, either or both of the inner plug wrapper <NUM> and the outer plug wrapper <NUM>, which constitute the center hole segment <NUM>, are also preferably made of the above-mentioned paper. The center hole segment <NUM> and the filter segment <NUM> may be connected with one outer plug wrapper <NUM>.

The perimeter length of the filter segment <NUM> is not particularly limited but is preferably <NUM> to <NUM>, more preferably <NUM> to <NUM>, and further preferably <NUM> to <NUM>. The length of the filter segment <NUM> in the axial direction (horizontal direction in <FIG>) is not particularly limited but is preferably <NUM> to <NUM> and more preferably <NUM> to <NUM>. The cross-sectional shape of the filter segment <NUM> is not particularly limited and may be circular, elliptic, or polygonal, for example.

As mentioned above, the center hole segment <NUM>' and the filter segment <NUM> may be connected with one outer plug wrapper <NUM>. The tobacco-containing segment <NUM>, the cooling segment <NUM>, and the joined center hole segment <NUM> and filter segment <NUM> are connected with a mouthpiece lining paper <NUM>. These three segments may be connected, for example, by applying a glue, such as a vinyl acetate-based glue, to the inner surface of the mouthpiece lining paper <NUM> and wrapping the lining paper around these segments.

The length of the heat-not-burn smoking article according to the present invention in the axial direction, in other words, the horizontal direction in <FIG> is not particularly limited but is preferably <NUM> to <NUM>, more preferably <NUM> to <NUM>, and further preferably <NUM> to <NUM>. The perimeter length of the heat-not-burn smoking article is preferably <NUM> to <NUM>, more preferably <NUM> to <NUM>, and further preferably <NUM> to <NUM>. In an exemplary embodiment, the length of the tobacco-containing segment <NUM> is <NUM>, the length of the cooling segment <NUM> is <NUM>, the length of the center hole segment <NUM> is <NUM>, and the length of the filter segment <NUM> is <NUM>. Here, the length of the filter segment <NUM> can be selected within the range of <NUM> to <NUM>. The length is selected such that the filter segment <NUM> has a resistance to draw per segment of <NUM> to <NUM> mmH<NUM>O/seg. The lengths of these individual segments may be changed appropriately depending on manufacturing feasibility, required quality, and so forth. Further, even an article in which only a filter segment is disposed downstream of a cooling segment without a center hole segment can also act as a heat-not-burn smoking article.

A heat-not-burn smoking system according to the present invention includes the heat-not-burn smoking article according to the present invention and a heating device for heating a tobacco-containing segment. Since the heat-not-burn smoking article according to the present invention is included, the heat-not-burn smoking system allows sufficient cooling of a vaporized aerosol component without destroying a smoking flavor. The heat-not-bum smoking system according to the present invention is not particularly limited provided that the heat-not-burn smoking article according to the present invention and the heating device are included and may have other configurations.

<FIG> illustrates an exemplary heat-not-burn smoking system according to the present invention. The heat-not-burn smoking system illustrated in <FIG> includes the heat-not-burn smoking article <NUM> according to the present invention and a heating device <NUM> for heating a tobacco-containing segment of the heat-not-burn smoking article <NUM> from the outside. <FIG> illustrates the state before inserting the heat-not-burn smoking article <NUM> into the heating device <NUM>, and <FIG> illustrates the state of heating the heat-not-burn smoking article <NUM> inserted into the heating device <NUM>. The heating device <NUM> illustrated in <FIG> includes a body <NUM>, a heater <NUM>, a metal tube <NUM>, a battery unit <NUM>, and a control unit <NUM>. The body <NUM> has a tubular recess <NUM>, and the heater <NUM> and the metal tube <NUM> are arranged on the inner side surface of the recess <NUM> at a position corresponding to the tobacco-containing segment of the heat-not-burn smoking article <NUM> inserted into the recess <NUM>. The heater <NUM> may be an electric resistance heater, and heating by the heater <NUM> is performed by supplying power from the battery unit <NUM> in accordance with instructions from the control unit <NUM>, which controls temperature. Heat generated by the heater <NUM> is transferred to the tobacco-containing segment of the heat-not-burn smoking article <NUM> through the metal tube <NUM> having a high thermal conductivity. In the schematic view of <FIG>, a gap exists between the outer perimeter of the heat-not-burn smoking article <NUM> and the inner perimeter of the metal tube <NUM>. However, such a gap between the outer perimeter of the heat-not-burn smoking article <NUM> and the inner perimeter of the metal tube <NUM> is actually and desirably absent for the purpose of efficient heat transfer. Although the heating device <NUM> heats the tobacco-containing segment of the heat-not-burn smoking article <NUM> from the outside, the heating device may be a heating device for heating from the inside.

The heating temperature by the heating device is not particularly limited but is preferably <NUM> or lower, more preferably <NUM> or higher and <NUM> or lower, and further preferably <NUM> or higher and <NUM> or lower. Herein, the heating temperature means the temperature of the heater in the heating device.

Heat-not-burn smoking articles of <NUM> in total length each comprising a tobacco-containing segment, a cooling segment, a center hole segment, and a filter segment joined in this order as illustrated in <FIG> were prepared. The dimensions of each segment are shown in Table <NUM>.

A row of <NUM> perforations was provided around the outer perimeter of the cooling segment. The perforations were placed at regular intervals to satisfy Vf of about <NUM> volume%. Herein, Vf is defined as a ratio of the amount of external air introduced from the perforations <NUM> to the total amount of gas inhaled by a user. The distance from the joined face between the cooling segment and the center hole segment to the perforations was set to <NUM> to <NUM>.

The filter segment of each heat-not-burn smoking article was connected to a smoking machine through a tube. A thermocouple was attached on the outer perimeter portion of the tube such that the tip of the thermocouple was placed at a position <NUM> from the mouth end on the surface of the heat-not-burn smoking article. The heat-not-burn smoking article was heated, in its tobacco-containing segment, by a heater and inhaled by the smoking machine. Heating by the heater was performed by holding at <NUM> for <NUM> seconds, holding at <NUM> for <NUM> seconds, and then holding at <NUM>. The inhalation was performed as <NUM> puffs in total at <NUM>/puff for <NUM> seconds (<NUM> second interval for each puff, i.e. <NUM> seconds for inhaling and <NUM> seconds for waiting) in accordance with the CIR (Canadian intense smoking regimen). A maximum temperature among temperatures in the respective puffs was recorded as a tip temperature. The results are shown in Table <NUM>.

Claim 1:
A heat-not-burn smoking article (<NUM>) comprising:
a tobacco-containing segment (<NUM>) containing tobacco and an aerosol former;
a tubular cooling segment (<NUM>, <NUM>) having one or more perforations (<NUM>) on the perimeter;
wherein
the heat-not-burn smoking article further comprises a tubular member (<NUM>) having an inner diameter smaller than the cooling segment (<NUM>, <NUM>), wherein
the cooling segment (<NUM>, <NUM>) is joined at the end in the mouth end direction to the member (<NUM>); and
the perforations (<NUM>) are provided at a position <NUM> to <NUM> from the joined face (O).