EP4643676A1

EP4643676A1 - Aerosol-cooling material for cigarette, and smoking article comprising same

Info

Publication number: EP4643676A1
Application number: EP23912556.0A
Authority: EP
Inventors: Yong Mi Jung; Tae Jeong Kim; Ho Young Kim; So Hyun Jung; Kyoung Hwan Oh; Moon Won Kim; Man Seok Seo
Original assignee: KT&G Corp; Seoul National University R&DB Foundation
Current assignee: KT&G Corp; SNU R&DB Foundation
Priority date: 2022-12-29
Filing date: 2023-11-10
Publication date: 2025-11-05
Also published as: KR102928588B1; KR20240106776A; CN120456835A; WO2024143878A1; JP2025541034A

Abstract

The present invention relates to an aerosol-cooling material for a cigarette, the material comprising a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, and being made of a porous foam or a porous sheet.

Description

TECHNICAL FIELD

The present disclosure relates to an aerosol-cooling material for a cigarette, and a smoking article including the same.

BACKGROUND ART

When a user inhales an aerosol generated by heating a medium portion of a smoking article, especially during the first puff, heat may occur (the temperature of the first puff ranges from 65°C to 75°C), which may cause discomfort to the smoker. This phenomenon may occur due to vapor generated by the heating of the medium portion.
To solve such problems, conventionally, methods such as forming perforations in a wrapper of a smoking article, applying a material that absorbs moisture to the smoking article, or including a cooling portion containing polylactic acid with a low glass transition temperature in the smoking article have been used. However, when perforations are formed in the wrapper of the smoking article, the dilution rate of the aerosol increases, and the issue of false inhalation may occur. When a material that absorbs moisture is applied to a smoking article, there is a problem where an atomization amount diminishes as the moisture content in the aerosol decreases. On the other hand, the cooling portion containing polylactic acid may have a minimal aerosol cooling effect when applied to the smoking article.
Accordingly, there is a need to develop a smoking article which may lower the temperature of an aerosol generated from a medium portion while not reducing an atomization amount.

DISCLOSURE OF THE INVENTION

TECHNICAL GOALS

The present disclosure is directed to providing a cooling material capable of lowering the temperature of an aerosol generated by heating a medium portion of a smoking article as the aerosol passes through the smoking article, while minimizing the space in which condensation of vapor may occur, thereby addressing the above-described problems.
However, the challenges to be addressed in the present disclosure are not limited to those mentioned above, and other unmentioned challenges will be clearly understood by those skilled in the art from the description below.

TECHNICAL SOLUTIONS

According to one embodiment of the present disclosure, there is provided an aerosol-cooling material for a cigarette, which includes a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, and is in the form of a porous foam or a porous sheet.
According to another embodiment of the present disclosure, there is provided a smoking article comprising a medium portion and a filter portion, wherein the smoking article includes an aerosol-cooling material for a cigarette, the aerosol-cooling material for a cigarette includes a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, and the aerosol-cooling material for a cigarette is in the form of a porous foam or a porous sheet.

EFFECTS OF THE INVENTION

The cooling material of the present disclosure is a disk of a certain thickness in the form of a porous foam or sheet, and includes a metal having a good thermal conductivity, so the temperature of an aerosol generated from a medium portion may be lowered without significantly changing the resistance of suction in smoking of a smoking article and without loss of vapor. Accordingly, a smoking article may be provided in which only heat sensation during the first puff is reduced without causing issues such as false inhalation or a decrease in an atomization amount.
The effect is not limited to the aforementioned effect, and it should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or the claims of the present disclosure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a control volume of a medium portion of a smoking article model.
FIG. 2 is a diagram illustrating a cooling portion of a smoking article model.
FIG. 3 is a diagram illustrating a filter portion of a smoking article model.
FIG. 4 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke according to the adjustment of a density of vapor in a smoking article model.
FIG. 5 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting the heat capacity of a porous medium (1) of a cooling portion.
FIG. 6 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting the length of a cooling portion.
FIG. 7 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting the length of a filter portion.
FIG. 8 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting an inner radius of a cooling portion.
FIG. 9 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting an outer radius of a cooling portion.
FIG. 10 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting a heat transfer coefficient of a cooling portion.
FIG. 11 is a diagram illustrating the measurement results of a first puff temperature of mainstream smoke by adjusting a thermal conductivity of a filter portion.
FIG. 12 is a diagram illustrating a side view of a smoking article in which a cooling material according to one embodiment of the present disclosure is included in a dual filter.
FIG. 13 is a diagram illustrating a side view of a smoking article in which a cooling material according to one embodiment of the present disclosure is included in a triple filter.
FIG. 14 is a diagram illustrating a side view of a smoking article in which a cooling material according to one embodiment of the present disclosure is included in a cooling portion.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, various alterations and modifications may be made to the embodiments. Here, the embodiments are not construed as limited to the disclosure. The embodiments should be understood to include all changes, equivalents, and replacements within the idea and the technical scope of the disclosure.
The terminology used herein is for the purpose of describing particular embodiments only and is not to be limiting of the embodiments. The singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises/comprising" and/or "includes/including" when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments belong. It will be further understood that terms, such as those defined in commonly-used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
When describing the embodiments with reference to the accompanying drawings, like reference numerals refer to like components and a repeated description related thereto will be omitted. In the following description of the embodiments, a detailed description of known functions and configurations incorporated herein will be omitted when the same may make the subject matter of the embodiments disclosed in the present specification rather unclear.
In addition, the terms first, second, A, B, (a), and (b) may be used to describe components of the embodiments. These terms are used only for the purpose of discriminating one component from another component, and the nature, the sequences, or the orders of the components are not limited by the terms.
A component, which has the same common function as a component included in any one embodiment, will be described by using the same name in other embodiments. Unless disclosed to the contrary, the description of any one embodiment may be applied to other embodiments, and the specific description of the repeated configuration will be omitted.
It will be understood that when a certain part "includes" a certain component, the part does not exclude another component but may further include another component.
A "smoking article" herein refers to an article capable of generating an aerosol, such as a cigarette, cigar, or the like. The smoking article may include an aerosol-generating material or an aerosol-forming material. The smoking article may further include solid materials based on tobacco raw materials such as plate-shaped leaf tobacco, cut tobacco, or reconstituted tobacco. A smoking material may include a volatile compound.
Additionally, throughout the disclosure, an "upstream" or "upstream direction" refers to a direction away from the mouth of a user who smokes the smoking article and a "downstream" or "downstream direction" refers to a direction toward the mouth of the user who smokes the smoking article.
When using a smoking article, the heat of the first puff of mainstream smoke may be caused by moisture in an aerosol generated from a medium portion. In order to reduce the heat sensation of the first puff, the temperature of the first puff was measured by controlling a density of the vapor in the smoking article, a heat capacity of the porous medium of a cooling portion, the length of the cooling portion, the length of a filter portion, an inner radius of the cooling portion, an outer radius of the cooling portion, a heat transfer coefficient of the cooling portion, and a thermal conductivity of the filter portion.
To investigate the process in which moisture evaporates and forms vapor inside the medium portion, a control volume of the medium portion may be set as shown in FIG. 1. Here, the temperature, density, and velocity inside the control volume are assumed to be constant regardless of location.
In addition, to investigate the vapor cooling process of the cooling portion, the cooling portion may be set up as shown in FIG. 2. The cooling portion may be in the form of a tube having a porous medium (1), and may be assumed to be a lumped system in which temperature of the porous medium tube is constant at all locations. The inner radius (r ₁) of the porous medium tube may be 2.5 mm, the outer radius (r ₂) may be 3.5 mm, and the length (l _c) of the cooling portion may be 12 mm.
To investigate the vapor cooling process of the filter portion, the filter portion may be set up as shown in FIG. 3. The filter portion may be in the form of paper wrapping around a porous medium (2). The length of the filter portion (l _ac) may be 14 mm, the inner radius (r _p1) of the paper wrapping around the porous medium (2) may be 3.4 mm, and the outer radius (r _p2) may be 3.5 mm.
The results of measuring the temperature of the first puff of mainstream smoke by controlling the density of the vapor in the smoking article, the heat capacity of the porous medium (1) of the cooling portion, the length of the cooling portion, the length of the filter portion, the inner radius of the cooling portion, the outer radius of the cooling portion, the heat transfer coefficient of the cooling portion, and the thermal conductivity of the filter portion are shown in FIGS. 4 to 11.

The values of the density of the vapor of the smoking article currently in use, the heat capacity of the porous medium (1) of the cooling portion, the length of the cooling portion, the length of the filter portion, the inner radius of the cooling portion, the outer radius of the cooling portion, the heat transfer coefficient of the cooling portion, the thermal conductivity of the filter portion, and the temperature of the vapor finally reaching the smoker are shown in Table 1 below, and the values are indicated by asterisks in FIGS. 4 to 11.

[Table 1]

Characteristics of smoking articles	Value
Density of vapor (kg/m³)	227.3
Heat capacity of the porous medium (1) of the cooling portion (J/m³·K)	171600
Length of the cooling portion (mm)	12
Length of the filter portion (mm)	14
Inner radius of the cooling portion (mm)	2.5
Outer radius of the cooling portion (mm)	3.5
Heat transfer coefficient of the cooling portion (W/m²·K)	68.5
Thermal conductivity of the filter portion (W/m·K)	0.058
Temperature of the final vapor (°C)	130.2

In light of the above results, it is expected that the temperature of the first puff of mainstream smoke may be lowered by increasing the length of the cooling portion, increasing the length of the filter portion, increasing the outer radius of the cooling portion, increasing the heat transfer coefficient of the cooling portion, or improving the thermal conductivity of the filter portion in the currently used smoking article. In particular, it can be found that the method of improving the thermal conductivity of the smoking article currently in use is most effective in lowering the temperature of the first puff of mainstream smoke.
Accordingly, as one embodiment of the present disclosure, an aerosol-cooling material for a cigarette may be provided, which may include a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, and may be in the form of a porous foam or a porous sheet. That is, by applying a cooling material including a metal having a high thermal conductivity to a smoking article, the temperature of the aerosol generated in the medium portion can be effectively reduced.
Any metal may be used as long as its thermal conductivity satisfies the above-mentioned range. For example, the metal may be at least one selected from the group consisting of aluminum (about 237 W/m·K), copper (about 372 W/m·K), stainless steel (about 12 to 45 W/m·K), gold (about 295 W/m·K), silver (about 418 W/m·K), iron (about 72 W/m·K), and graphene (about 5000 W/m·K), but is not limited to the examples described.
In a cooling material according to one embodiment of the present disclosure, the porous foam may have a disk-shaped structure with a certain thickness. This structure is more advantageous in preventing condensation of moisture in an aerosol generated from the medium portion, since there is less space for moisture to condense due to collision with the cooling portion, compared to a conventional cooling portion made by folding a sheet longitudinally.
Also, the porous sheet may be a metal nonwoven fabric, or a metal woven fabric made of metal yarn. The porous sheet may be in a crimped form.
Additionally, in terms of maintaining an atomization amount of a smoking article and resistance of suction in smoking and providing excellent cooling effects, the porous foam may be more preferable than the porous sheet.
An aerosol-cooling material for a cigarette according to one embodiment of the present disclosure may have porous characteristics. An aerosol generated in the medium portion may pass through the pores and reach the smoker's mouth.
Here, a porosity of the aerosol-cooling material for a cigarette may be 60% to 90%, and preferably 80% to 90%. In addition, the pore volume of the porous sheet may be 70,000 CU or more, and the porosity of the aerosol-cooling material for a cigarette in which a porous sheet is used in a crimped form may be within the above-described range. When the porosity and the pore volume are lower than the lower limits of the above-described ranges, the resistance of suction in smoking may increase and the flow of mainstream smoke may be hindered, which may result in false inhalation or inability to smoke. In contrast, when the the porosity and the pore volume exceed the upper limits of the above-described ranges, there is a problem in that the temperature of mainstream smoke cannot be effectively lowered because the space occupied by the metal is small and it is difficult for the high-temperature vapor to meet the metal.
The basis weight of an aerosol-cooling material for a cigarette according to one embodiment of the present disclosure may be 40 g/cm³ to 80 g/cm³. When the basis weight is less than 40 g/cm³, the thickness of the cooling material may become thin, which may deteriorate workability during the manufacture of the smoking article. In contrast, when the basis weight exceeds 80 g/cm³, the thickness of the cooling material may become thick, the porosity may decrease, and the air flow may be hindered, which may increase the resistance of suction in smoking.
The length of an aerosol-cooling material for a cigarette according to one embodiment of the present disclosure may be 3 mm to 10 mm. When the length is less than 3 mm, the area that can come into contact with the cooling material may be reduced, making it impossible to sufficiently lower the temperature of the first puff of mainstream smoke. In contrast, when the length exceeds 10 mm, the entire filter portion must be replaced with the cooling material. This may result in poor aesthetics, excessive cooling, and increased resistance of suction in smoking, which in turn may cause false inhalation or inability to smoke.
In another embodiment of the present disclosure, a smoking article may be provided including a medium portion and a filter portion, wherein the smoking article may include an aerosol-cooling material for a cigarette. Here, the aerosol-cooling material for a cigarette may include a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, and may be in the form of a porous foam or a porous sheet.
The smoking article of the present disclosure may correspond to, for example, a combustible or non-combustible smoking article. A combustible smoking article may refer to a traditional cigarette. A non-combustible smoking article may refer to a smoking article that is indirectly heated by electric energy rather than by direct combustion.
The medium portion is an aerosol-generating material that releases volatile compounds when heated, typically containing tobacco material including nicotine, and may additionally contain excipients such as a binder or other additives. As an example, the tobacco medium included in a tobacco rod of the present disclosure may be manufactured in the form of granules containing tobacco material and excipients. For example, the tobacco material may be tobacco leaf fragments, tobacco stems, tobacco dust generated during tobacco processing, and/or tobacco leaf strips. The tobacco leaves may be at least one selected from the group consisting of yellow, burley, orient, cigar and toast. However, embodiments are not limited thereto.
The filter portion may be located downstream of the medium portion, and may be a cellulose acetate filter, a paper filter, or a filter made of a polymer material. However, embodiments are not limited thereto.
In a smoking article according to one embodiment of the present disclosure, the filter portion may include the aerosol-cooling material for a cigarette, and may include a single filter segment or a plurality of filter segments. For example, a filter including a plurality of filter segments may be a dual filter or a triple filter.
A smoking article according to one embodiment of the present disclosure may further include a cooling portion between the medium portion and the filter portion. The cooling portion may be used to cool an aerosol generated by heating the medium portion, thereby allowing the smoker to inhale the aerosol cooled to an appropriate temperature.
The cooling portion may include a biodegradable or natural polymer material. For example, polylactic acid may be used in the cooling portion, and the content of polylactic acid may be 30% to 100%.
The cooling portion may be, for example, a tubular structure including a hollow therein. The aerosol moves through the hollow, and at this time, the temperature of the aerosol may be lowered by perforations, a moisture-absorbing material, a cooling material, and the like.
The cooling portion may maximize the cooling effect of the aerosol by including the aerosol-cooling material for a cigarette.
The temperature of mainstream smoke of a smoking article according to one embodiment of the present disclosure may be 40°C to 65°C. The temperature of mainstream smoke of the smoking article may be 5°C to 25°C lower than the temperature of mainstream smoke of a smoking article that does not include the cooling material.
The moisture content in a smoking article according to one embodiment of the present disclosure may be 3 to 8 mg/cig. Typically, the moisture content in the medium portion of a smoking article may be 4.7 mg/cig to 7.4 mg/cig, and the same applies to a smoking article according to one embodiment of the present disclosure. The cooling material does not absorb moisture due to the nature of the material, and since the aerosol moves quickly within the cooling material, there is a low possibility that moisture will be absorbed and remain. Accordingly, it is possible to provide a smoking article in which moisture in the aerosol generated from a medium portion is hardly condensed and an atomization amount does not change.
The resistance of suction in smoking of a smoking article according to one embodiment of the present disclosure may be 98 mmH₂O to 102 mmH₂O, which may exhibit a slight difference of up to 6 mmWG compared to the resistance of suction in smoking of a smoking article that does not include a cooling material. That is, even if the cooling material is used, a smoking article can be provided that does not significantly reduce the resistance of suction in smoking.
Hereinafter, the present disclosure will be described in more detail with reference to examples, however, the present disclosure is not limited to the following examples.

Experimental Example 1: Measurement of Temperature of the First Puff of Mainstream Smoke Depending on the Material of the Cooling Portion and the Presence or Absence of Perforations

1. Preparation of Smoking Articles

Comparative Example 1

A smoking article including a medium portion and a filter portion was prepared, wherein the filter portion further included a tip paper that wraps around the filter portion (no perforation is formed).

Comparative Example 2

A smoking article was prepared in the same manner as in Comparative Example 1, except that the tip paper included perforations.

Comparative Example 3

A smoking article was prepared in the same manner as in Comparative Example 1, except that the smoking article further included a cooling portion between the medium portion and the filter portion, the cooling portion was made of a paper filter material (a moisture-absorbing material), and the tip paper included perforations.

Comparative Example 4

A smoking article was prepared in the same manner as in Comparative Example 1, except that the smoking article further included a cooling portion between the medium portion and the filter portion, the cooling portion was a paper tube, and had a length of 12 mm.

Comparative Example 5

A smoking article was prepared in the same manner as in Comparative Example 1, except that the smoking article further included a cooling portion between the medium portion and the filter portion, and the cooling portion was prepared by cutting a material, in which a PLA film laminate (thickness 15 µm) had been applied to a 24K porous paper, to a length of 12 mm and then crimping the cut material.

Comparative Example 6

A smoking article was prepared in the same manner as in Comparative Example 1, except that the smoking article further included a cooling portion between the medium portion and the filter portion, and the cooling portion was prepared by cutting a material, in which a PLA film laminate (thickness 15 µm) had been applied to a silver foil (basis weight 35 gsm), to a length of 12 mm and then crimping the cut material.

Comparative Example 7

A smoking article was prepared in the same manner as in Comparative Example 1, except that the smoking article further included a cooling portion between the medium portion and the filter portion, the cooling portion was prepared by cutting an aluminum foil to a length of 12 mm and then crimping the cut aluminum foil.

2. Measurement of Temperature of the First Puff of Mainstream Smoke

The temperature of the first puff of mainstream smoke of Comparative Examples 1 to 7 was measured by the following method. A thermocouple was fixed at a position 1 to 2 mm away from the center of the filter portion of the smoking article. The smoking article was then preheated for 35 seconds using a smoking machine, followed by puffing for 35 to 37 seconds, during which the highest temperature value was measured. The results are shown in Table 2 below.

[Table 2]

Division	Temperature of the first puff of mainstream smoke (°C)	Decreased temperature (°C)
Comparative Example 1	130.2	-
Comparative Example 2	66.9	63.3 (relative to Comparative example 1)
Comparative Example 3	46.6	20.3 (relative to Comparative example 2)
Comparative Example 3	86.4	43.8 (relative to Comparative example 1)
Comparative Example 4	86.9	43.3 (relative to Comparative example 1)
Comparative Example 5	86.6	43.6 (relative to Comparative example 1)
Comparative Example 6	87.2	43.0 (relative to Comparative example 1)

Compared to Comparative Example 1, Comparative Examples 4 to 7, in which a cooling portion was applied to a smoking article, showed a decrease in the temperature of the first puff of mainstream smoke by about 43°C. Comparing Comparative Examples 4 to 7, it was found that regardless of whether the material of the cooling portion was paper, polylactic acid, or aluminum foil, the temperature of the first puff when the smoking article was used was constant at 85°C to 90°C, so that there was no significant change in the temperature of the first puff depending on the change in material.
In contrast, Comparative Example 2 showed that the temperature of the first puff dropped by 60°C or more compared to Comparative Example 1, and by about 20°C compared to Comparative Examples 4 to 7. This means that forming perforations is more effective in lowering the temperature of the first puff of mainstream smoke than changing the material of the cooling portion. However, in Comparative Example 2, the air dilution rate was 65%, which is higher than that of Comparative Example 1, and this resulted in a decrease in the taste of the tobacco and the occurrence of false inhalation.
Comparative Example 3, in which both perforations and a moisture-absorbing material were used, showed that the temperature of the first puff decreased by about 20°C compared to Comparative Example 2. However, due to the use of the moisture-absorbing material, the vapor density decreased by 30% compared to Comparative Example 2, resulting in a reduction in the atomization amount.

Experimental Example 2: Measurement of Temperature of the First Puff of Mainstream Smoke, Atomization Amount, and Resistance of Suction in Smoking by Applying an Aerosol-Cooling Material for a Cigarette

1. Preparation of cooling materials

(1) Design of a Cooling Material Being in the Form of a Porous Aluminum Foam

The design details of the cooling material being in the form of a porous aluminum foam are as shown in Table 1 below. [Table 3]

Length (mm) Porosity (%) Resistance of suction in smoking (mmH₂O)

4 to 8 0.6 or more 10 or less

(2) Preparation of a Cooling Material Made of a Porous Aluminum Nonwoven Fabric

A cooling material made of an aluminum nonwoven fabric was prepared by the following method. First, an aluminum nonwoven fabric was prepared by dipping a porous nonwoven filter made of polypropylene fibers into an aluminum precursor ink containing 15 mM AlCl₃ and 53 mM LiAlH₄ and drying the resulting ink. The cooling material was prepared by crimping and then rolling the above aluminum nonwoven fabric. The physical properties of the prepared cooling material are shown in Table 4 below. [Table 4]

Thickness of a porous aluminum nonwoven fabric (mm) Pore volume (CU) Basis weight (g/cm³) Thickness of fiber (µm)

0.24 70000 or more 61.75 31.64

2. Preparation of Smoking Articles

Example 1

A smoking article was prepared which includes a medium portion, a cooling portion 10 located downstream of the medium portion, and a filter portion 14 located downstream of the cooling portion. Here, the filter portion was a double filter, the double filter included a cooling material 16, and the cooling material 16 was a cooling material being in the form of a porous aluminum foam (FIG. 12). The filter portion includes a tip paper that wraps around the filter portion. The tip paper has perforations formed therein.

Example 2

A smoking article was prepared in the same manner as in Example 1, except that the filter portion 24 located downstream of the cooling portion 20 was a triple filter, the triple filter included a cooling material 26, and the cooling material 26 was a cooling material being in the form of a porous aluminum foam (FIG. 13).

Example 3

A smoking article was prepared in the same manner as in Example 1, except that the cooling portion 30 included two cooling segments, the cooling portion 30 included a cooling material 36, the cooling material 36 was a cooling material being in the form of a porous aluminum foam, and the filter unit 34 including a single filter segment was located downstream of the cooling portion (FIG. 14).

Example 4

A smoking article was prepared in the same manner as in Example 1, except that a cooling material made of a porous aluminum nonwoven fabric was crumpled and used instead of a cooling material being in the form of a porous aluminum foam (FIG. 12).

Example 5

A smoking article was prepared in the same manner as in Example 2, except that a cooling material made of a porous aluminum nonwoven fabric was crumpled and used instead of a cooling material being in the form of a porous aluminum foam (FIG. 13).

Example 6

A smoking article was prepared in the same manner as in Example 3, except that a cooling material made of a porous aluminum nonwoven fabric was crumpled and used instead of a cooling material being in the form of a porous aluminum foam (FIG. 14).

3. Measurement of Temperature of the First Puff of Mainstream Smoke

The temperature of the first puff of mainstream smoke from Examples 1 to 6 was measured by the following method. A thermocouple was fixed at a position 1 to 2 mm away from the center of the filter portion of the smoking article. The smoking article was then preheated for 35 seconds using a smoking machine, followed by puffing for 35 to 37 seconds, during which the highest temperature value was measured.

The results are shown in Table 5 below.

[Table 5]

Division	Temperature of the first puff of mainstream smoke (°C)	Temperature change (°C) (relative to Comparative Example 2)
Example 1	48.4	Decreased by 18.5°C
Example 2	64.8	Decreased by 2.1°C
Example 3	55.9	Decreased by 10°C
Example 4	57.8	Decreased by 9.1°C
Example 5	78.9	Increased by 12°C
Example 6	56.9	Decreased by 10°C

Examples 1 to 4 and 6 showed that the temperature of the first puff of mainstream smoke was lowered by 2.1°C to 18.5°C compared to Comparative Example 2.
In addition, under the same conditions, each of Examples 1 to 3 showed a lower temperature of the first puff of mainstream smoke compared to each of Examples 4 to 6, confirming that the cooling material being in the form of a porous foam is more effective in reducing the aerosol temperature than the cooling material being in the form of a porous sheet.
In contrast, in Comparative Example 3 including a cooling portion containing a moisture-absorbing material, the temperature of the first puff of mainstream smoke was significantly reduced, similar to Examples 1 to 6. However, due to the presence of the moisture-absorbing material, the moisture content in the first puff was reduced compared to Examples 1 to 6, resulting in a significant decrease in the atomization amount.
Furthermore, when the cases in which the perforations of Examples 1 to 6 were blocked were compared with Comparative Example 1 in terms of the resistance of suction in smoking, it was confirmed that the cooling material of the present disclosure did not affect the resistance of suction in smoking of the smoking articles.
From the above experimental examples, it can be expected that, by using a smoking article including a cooling material described in the claims of the present disclosure, a smoking article can be provided which may effectively lower the temperature of an aerosol generated from a medium portion without problems of a decrease in an atomization amount and a decrease in the resistance of suction in smoking.
While the embodiments have been described with reference to the limited drawings, it will be apparent to one of ordinary skill in the art that various alterations and modifications can be made from the above description. For example, suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents.
Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

- Reference Numerals

10, 20, 30 : Cooling portion
14, 24, 34 : Filter portion
16, 26, 36 : Cooling material

Claims

An aerosol-cooling material for a cigarette, comprising a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, the material being in the form of a porous foam or a porous sheet.
The aerosol-cooling material for a cigarette of claim 1, wherein the porous foam is in the form of a disk.
The aerosol-cooling material for a cigarette of claim 1, wherein the porous sheet is made of a metal nonwoven fabric or a metal woven fabric.
The aerosol-cooling material for a cigarette of claim 1, wherein the porous sheet is in a crimped form.
The aerosol-cooling material for a cigarette of claim 1, wherein the metal is at least one selected from the group consisting of aluminum, copper, stainless steel, gold, silver, iron, and graphene.
The aerosol-cooling material for a cigarette of claim 1, wherein the porosity of the aerosol-cooling material for a cigarette is 60% to 90%.
The aerosol-cooling material for a cigarette of claim 1, wherein the basis weight of the aerosol-cooling material for a cigarette is 40 g/cm² to 80 g/cm².
The aerosol-cooling material for a cigarette of claim 1, wherein the length of the aerosol-cooling material for a cigarette is 3 mm to 10 mm.
A smoking article comprising a medium portion and a filter portion,
wherein the smoking article comprises an aerosol-cooling material for a cigarette, the aerosol-cooling material for a cigarette comprises a metal having a thermal conductivity of 10 W/m·K to 5000 W/m·K, and

the material is in the form of a porous foam or a porous sheet.
The smoking article of claim 9, wherein the filter portion comprises the aerosol-cooling material for a cigarette, and comprises a single filter segment or a plurality of filter segments.
The smoking article of claim 9, further comprising a cooling portion between the medium portion and the filter portion,
wherein the cooling portion comprises the aerosol-cooling material for a cigarette.
The smoking article of claim 9, wherein the smoking article is a combustible or non-combustible smoking article.