Filter tip for cigarette and heat-not-burn cigarette

Abstract

The invention provides a filter tip for a cigarette and a heat-not-burn cigarette. The filter tip is provided with a first end portion and a second end portion in the extending direction of the filter tip, the filter tip comprises a main body portion and a smoke circulation hole formed in the main body portion, the smoke circulation hole is provided with a continuous through hole enabling gas to circulate between the first end portion and the second end portion, and the main body portion comprises a first main material and a second main material. The specific heat capacity of the first main material at 0-100 DEG C is 700-1110 J / kg.K, the heat conductivity coefficient is 1-5 W / m.K, and the linear expansion coefficient is 3 * 10 <-7 >-8 * 10 <-6 > / DEG C. The first main material has a high heat conductivity coefficient and specific heat capacity, the heat dissipation performance is good, and water vapor in smoke can be more easily condensed on the first main material in the suction process. The moisture content in the flue gas can be reduced, and the temperature of the flue gas can be reduced. Due to the low linear expansion coefficient, the thermal stability at the high temperature is good, and the situation that the flue gas flow channel deforms, and the flue gas amount is reduced due to flue gas adsorption is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heating tobacco, in particular to a filter for a smoking article and a heat-not-burn smoking article. BACKGROUND

[0002] A conventional heat-not-burn smoking article mainly comprises a core material segment, a support segment, a temperature reduction segment and a filter segment. The support segment mainly supports the core material segment, and the temperature reduction segment aims to reduce the temperature of the smoke. At present, the support segment, the temperature reduction segment and the filter segment are mostly made of acetate fibers. Since the length of the heat-not-burn smoking article is relatively short, if the high-temperature smoke generated by the tobacco material in the core material segment (heating temperature: 300-400 o C) does not undergo temperature reduction and reaches the oral cavity, the consumer will be burned. In addition, since the heat-not-burn smoking article mainly uses glycerol and propylene glycol as the smoking agent, the hygroscopicity of glycerol will cause the moisture content of the core material to increase during storage. Therefore, during the heating process of the heat-not-burn smoking article, the water vapor content in the first few puffs of smoke is relatively high, and the tobacco material will also generate part of the water vapor during the pyrolysis process.

[0003] Compared with other key components in the smoke, such as glycerol, propylene glycol and nicotine, water has a relatively low boiling point, which means that during the cooling process of the smoke, water is more likely to reach its condensation point and undergo phase change. Since the heat of vaporization of water (2260 kJ / kg) is relatively large, the heat released by the condensation of water is an important part of the energy in the system. If the water content in the smoke cannot be effectively reduced, the heat released by the condensation of excessive water vapor in the oral cavity will burn the oral cavity.

[0004] The structure of the conventional composite filter is mostly a binary filter structure or a ternary filter structure. The binary filter is a temperature reduction solid + solid acetate fiber structure, and the ternary filter is a hollow acetate fiber + temperature reduction solid + solid acetate fiber structure. Although the composite filter with the above structure can reduce the temperature of the smoke, since it is made of acetate fiber bundles, the acetate fiber bundles themselves have high adsorption performance, and the interception by the bundles will cause the smoke volume to decrease, affecting the smoking experience of the consumer. SUMMARY

[0005] The present application provides a filter for a smoking article and a heat-not-burn smoking article to improve the temperature reduction effect of the filter.

[0006] The first aspect of the present application provides a filter for a smoking article, the filter having a first end portion and a second end portion in the extension direction thereof, the filter comprising a main body portion and a smoke flow passage hole provided in the main body portion, the smoke flow passage hole having a continuous through hole for allowing gas to flow between the first end portion and the second end portion, the main body portion comprising a first main material, the specific heat capacity of the first main material between 0-100 ℃ being 700-1110 J / kg·K, the thermal conductivity being 1-5 W / m·K, and the linear expansion coefficient being 3×10 -7-8×10 -6 / ℃.

[0007] In any embodiment of the first aspect, the first main material comprises one or more of quartz, silicate ceramic, high borosilicate glass.

[0008] In any embodiment of the first aspect, the porosity of the main body part is 5%-30%.

[0009] In any embodiment of the first aspect, the main body part is a tubular main body part, and the through hole of the tubular main body part is a flue gas flow-through hole.

[0010] In any embodiment of the first aspect, the tubular main body part has a circular ring cross section along a cross section perpendicular to the extending direction.

[0011] In any embodiment of the first aspect, the inner wall of the tubular main body part has a rough surface, preferably the roughness of the rough surface is Ra 1.5-12.5 μm.

[0012] In any embodiment of the first aspect, the tubular main body part has a tube wall thickness of 1.0-1.5 mm and / or a length of 33-45 mm.

[0013] In any embodiment of the first aspect, the flue gas flow-through hole comprises one or more channels extending spirally along the extending direction; or the flue gas flow-through hole comprises a plurality of through holes parallel to each other; or the inner wall of the flue gas flow-through hole is provided with protrusions.

[0014] In any embodiment of the first aspect, the cross-sectional area of the flue gas flow-through hole gradually increases along a direction from the first end part to the second end part, and / or the inner wall of the flue gas flow-through hole is provided with a hydrophilic coating or holes.

[0015] In any embodiment of the first aspect, the main body part further comprises a second main material, the specific heat capacity of the second main material between 0-100℃ is 300-600 J / kg·K, the thermal conductivity is 15-20 W / m·K, and the linear expansion coefficient is 10×10 -6 -15×10 -6 / ℃, and the first main material and the second main material are inlaid or arranged alternately along the extending direction.

[0016] In any embodiment of the first aspect, at least the second end part of the main body part is the first main material, and the length of the first main material located at the second end part is 3-8 mm.

[0017] In any embodiment of the first aspect, the second main material is one or more of stainless steel, copper alloy, aluminum, or graphene-based thermal conductive composite material.

[0018] The second aspect of the present application provides a heat-not-burn cigarette, comprising a cigarette core material and a filter, wherein the filter comprises the filter provided by any of the embodiments of the first aspect, and the end of the filter away from the cigarette core material is made of the first main material.

[0019] The first main material used in the filter of the present application has a high thermal conductivity and specific heat capacity, and good heat dissipation performance, which can make the water vapor in the smoke more easily condense on the first main material during the smoking process. The heat released by condensation can be transferred away through heat exchange between the quartz tube and the surrounding air, which can not only reduce the moisture content in the smoke, but also reduce the temperature of the smoke. At the same time, the first main material has a low linear expansion coefficient, so its thermal stability at high temperature is good, and it will not cause deformation of the smoke flow channel and adsorption of the smoke, resulting in a decrease in the amount of smoke. In summary, the filter for the cigarette of the present application not only has a good cooling effect on the smoke, but also does not affect the smoking experience of the consumer. BRIEF DESCRIPTION OF DRAWINGS

[0020] The drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 The temperature of the outlet smoke of the filter-heated cigarette of each embodiment and the comparative example is shown.

[0022] Figure 2 The wall temperature (9 mm from the smoking end) of the filter-heated cigarette of each embodiment and the comparative example is shown. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, and is by no means any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the description of the present application is only for the purpose of describing the specific embodiments and is not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0025] The conventional composite filter has insufficient cooling effect, resulting in reduced oral comfort. To solve this problem, the application provides a filter for a cigarette and a heat-not-burn cigarette.

[0026] The first embodiment of the application provides a filter for a cigarette, the filter having a first end portion and a second end portion in the extension direction thereof, the filter comprising a main body portion and a smoke flow passage hole provided in the main body portion, the smoke flow passage hole having a continuous through hole for allowing gas to flow between the first end portion and the second end portion, the main body portion comprising a first main material, the specific heat capacity of the first main material being 700-1110 J / kg·K, the thermal conductivity of the first main material being 1-5 W / m·K, and the linear expansion coefficient of the first main material being 3×10 -7 -8×10 -6 / ℃.

[0027] The first main material used in the filter of the application has a high thermal conductivity and specific heat capacity, and has good heat dissipation performance, which can make the water vapor in the smoke more easily condense on the first main material during smoking. The heat released by condensation can be transferred away through heat exchange between the quartz tube and the surrounding air, which can not only reduce the moisture content in the smoke, but also reduce the temperature of the smoke. At the same time, the first main material has a low linear expansion coefficient, so it has good thermal stability at high temperatures and will not cause deformation of the smoke flow passage and adsorption of the smoke, resulting in a decrease in the amount of smoke. In summary, the filter for a cigarette of the application not only has a good cooling effect on the smoke, but also does not affect the smoking experience of consumers.

[0028] The specific heat capacity is the specific heat capacity of the material tested at 0-100℃, the thermal conductivity is the thermal conductivity of the material at 20℃, and the linear expansion coefficient is the linear expansion coefficient of the material tested at 0-100℃.

[0029] In some embodiments, the first main material comprises one or more of quartz, silicate ceramic, and high borosilicate glass. The above-mentioned materials not only meet the above-mentioned conditions, but also have a wide source and low cost. In addition, quartz and high borosilicate glass are transparent and beautiful, further improving the consumer experience.

[0030] In some embodiments, the porosity of the main body portion is 5%-30%. This can reduce the resistance of the smoke flow and improve the permeability of the smoke.

[0031] The above-mentioned porosity can be achieved by forming a porous structure in the main body portion or by forming pores using channels. In some embodiments, the main body portion is a tubular main body portion, and the through hole of the tubular main body portion is the smoke flow passage hole. The structure of the tubular main body portion is simple and easy to manufacture, the smoke flow passage is smoother, and the condensed water is easy to clean.

[0032] In some embodiments, the tubular main body portion has a circular ring cross-section in a cross-section perpendicular to the extension direction.

[0033] In some embodiments, the inner wall of the tubular body has a rough surface, preferably with a roughness Ra of 1.5 μm to 12.5 μm. The rough surface with this roughness provides more area for heat exchange and condensation of water vapor, further improving the cooling and water vapor condensation effects.

[0034] In some embodiments, the wall thickness of the tubular main body is 1.0-1.5 mm. This wall thickness allows for sufficient cooling of the flue gas while preventing excessive heat conduction to the surface, which would reduce the user experience.

[0035] In some implementations, the length is 33-45 mm. This achieves both sufficient cooling of the flue gas and allows the flue gas to reach the oral cavity more quickly.

[0036] There are various design options for the smoke flow holes in a filter. For example, to further improve the cooling effect, the cooling path can be extended. In some embodiments, the smoke flow holes include one or more channels extending in a spiral shape along the extension direction. For example, to shorten the time it takes for the smoke to reach the mouth while maintaining a cooling effect, in some embodiments, the smoke flow holes include multiple parallel through holes. For example, to maximize the condensation of water vapor, in some embodiments, the inner wall of the smoke flow holes is provided with protrusions.

[0037] In some embodiments, the cross-sectional area of ​​the flue gas flow hole gradually increases from the first end to the second end. In use, the second end serves as the oral suction end. This arrangement accelerates flue gas flow, reduces condensation buildup in the flow hole, and simultaneously reduces airflow resistance through the gradually expanding structure, improving the suction experience.

[0038] In some embodiments, the inner wall of the flue gas flow hole is provided with a hydrophilic coating or pores. The hydrophilic coating or pores further improve the condensation efficiency of water vapor.

[0039] In some embodiments, the hydrophilic coating may be either a polyvinyl alcohol (PVA) coating or a polyethylene glycol (PEG) coating.

[0040] In some embodiments, the main body further includes a second main material, which has a specific heat capacity of 300-600 J / kg·K between 0-100°C, a thermal conductivity of 15-20 W / m·K, and a coefficient of linear expansion of 10×10⁻⁶. -6 -15×10 -6 / ℃, the first and second main materials are embedded or alternately arranged along the extension direction. The second main material has a higher thermal conductivity, and together with the first main material, it further improves the cooling effect of the filter.

[0041] The inlaid arrangement of the first main material and the second main material can be that the first main material is the base and the second main material is the embedded material, or that the second main material is the base and the first main material is the embedded material, and different inlaid patterns are designed to make the filter more beautiful.

[0042] In some embodiments, the second end portion of the main body portion is the first main material, and the length of the first main material at the second end portion is 3-8 mm.

[0043] With the second end portion with the first main material as the oral suction end, the dry and hot feeling at the oral position can be reduced due to the high specific heat capacity and low thermal conductivity, and the smoking experience is improved.

[0044] In some embodiments, the second main material is one or more of stainless steel, copper alloy, aluminum, or graphene-based thermal conductive composite material. The graphene-based thermal conductive composite material described above can be a graphene-based thermal conductive composite material that is conventional or commercially available in the art, and the present application does not make special requirements thereon.

[0045] The second embodiment of the present application provides a heat-not-burn cigarette, comprising a cigarette core material and a filter, the filter comprising any one of the filters provided in the first embodiment, and the end portion of the filter away from the cigarette core material being the first main material. Since the filter provided in the present application has good cooling effect and structural stability, the smoking experience of consumers can be improved.

[0046] The beneficial effects of the present application will be further illustrated below in combination with examples and comparative examples.

[0047] Example 1 Figure 1 and 2 The quartz tube 33 mm (wall thickness 1.5 mm) in the table is used as the filter.

[0048] The quartz tube with a cylindrical through hole in the middle is used as the filter, the length of the quartz tube is 33 mm, the outer diameter is 7.2 mm, the wall thickness is 1.5 mm, the inner wall is smooth, the thermal conductivity of quartz is 1.4 W / m·K (20 ℃), the specific heat capacity is 758 J / kg·K (0-100 ℃), and the linear expansion coefficient is 5.5×10⁻ 7 / ℃.

[0049] Example 2 Figure 1 and 2 The quartz tube 33 mm (wall thickness 1 mm) in the table is used as the filter.

[0050] The quartz tube with a cylindrical through hole in the middle is used as the filter, the length of the quartz tube is 33 mm, the outer diameter is 7.2 mm, the wall thickness is 1.0 mm, and the inner wall is smooth.

[0051] Example 3 Figure 1 and 2The middle mark is a quartz tube 33 mm (rough, wall thickness 1.5 mm)

[0052] The quartz tube with a cylindrical through hole in the middle is used as the filter tip, and the length of the quartz tube is 33 mm, the outer diameter is 7.2 mm, the wall thickness is 1.5 mm, the inner wall is rough, and the roughness Ra is 5 μm.

[0053] Example 4 ( Figure 1 and 2 The middle mark is a quartz tube 40 mm (wall thickness 1.5 mm)

[0054] The quartz tube with a cylindrical through hole in the middle is used as the filter tip, and the length of the quartz tube is 40 mm, the outer diameter is 7.2 mm, the wall thickness is 1.5 mm, and the inner wall is smooth.

[0055] Example 5 ( Figure 1 and 2 The middle mark is a quartz tube 45 mm (wall thickness 1.5 mm)

[0056] The quartz tube with a cylindrical through hole in the middle is used as the filter tip, and the length of the quartz tube is 45 mm, the outer diameter is 7.2 mm, the wall thickness is 1.5 mm, and the inner wall is smooth.

[0057] Comparative Example 1 ( Figure 1 and 2 The middle mark is a stainless steel tube 33 mm (wall thickness 1.5 mm)

[0058] The 304 stainless steel tube with a cylindrical through hole in the middle is used as the filter tip, and the length of the 304 stainless steel tube is 33 mm, the outer diameter is 7.2 mm, the wall thickness is 1.5 mm, and the inner wall is smooth. The thermal conductivity of 304 stainless steel is 15 W / m·K, the specific heat capacity is 500 J / kg·K, and the linear expansion coefficient is 15×10⁻ 7 / ℃.

[0059] Comparative Example 2 ( Figure 1 and 2 The middle mark is a stainless steel tube 33 mm (wall thickness 1.0 mm)

[0060] The 304 stainless steel tube with a cylindrical through hole in the middle is used as the filter tip, and the length of the 304 stainless steel tube is 33 mm, the outer diameter is 7.2 mm, the wall thickness is 1.0 mm, and the inner wall is smooth.

[0061] Comparative Example 3 ( Figure 1 and 2 The middle mark is a thin-walled cellulose acetate hollow tube (wall thickness 1 mm)

[0062] The filter tip is a cellulose acetate tube with a cylindrical hole in the middle, which has a length of 33 mm, an outer diameter of 7.2 mm, a wall thickness of 1.5 mm, and a smooth inner wall.

[0063] Comparative Example 4 Figure 1 and 2 The thick-walled cellulose acetate tube (wall thickness 1.5 mm) is marked in the table.

[0064] The filter tip is a cellulose acetate tube with a cylindrical hole in the middle, which has a length of 33 mm, an outer diameter of 7.2 mm, a wall thickness of 1.0 mm, and a smooth inner wall.

[0065] The tobacco core segment of the heated cigarette has a length of 13 mm, and is wrapped with cigarette paper with a basis weight of 60 g / m 2 The filter tip of each example and comparative example is wrapped and connected with the cigarette paper with a basis weight of 36 g / m 2 During the smoking process, the smoke is captured by a Cambridge filter through the filter tip. After the smoking process, the filter and the filter tip are extracted with isopropyl alcohol solvent, and then subjected to quantitative analysis by gas chromatography. The analysis results are shown in Table 1.

[0066] The retention rate of the heated cigarette with the filter tip of the connecting example and comparative example on the key components in the smoke is calculated according to the following formula:

[0067] 00%

[0068] S 滤嘴 represents the mass of the corresponding component in the filter tip, and S 烟气 represents the mass of the corresponding component in the filter.

[0069] Table 1

[0070] As can be seen from Table 1, compared with the cellulose acetate tube of the comparative example, the quartz tube has a higher water retention rate (more than 2 times) and a lower retention rate of propylene glycol, glycerol and nicotine (consistent with the larger amount of smoke and stronger satisfaction during smoking).

[0071] Figure 1 The temperature of the smoke at the outlet of the heated cigarette with different filter tips is shown. It can be clearly seen that the temperature of the heated cigarette with the quartz tube filter rod is significantly lower than that of the cellulose acetate tube heated cigarette. This may be related to the easier condensation of water vapor on the quartz surface, which is consistent with the higher water retention rate (see Table 1).

[0072] Figure 2The wall temperature (9 mm from the suction end) of different filter heating cigarettes during each puff is shown. Compared with quartz tube, stainless steel has lower specific heat (500 J / kg·K) and higher thermal conductivity (16-20 W / m·K), so that the temperature of heating cigarette during suction is easily conducted to the low-temperature suction end through the high-temperature heating zone, resulting in that the filter end wall temperature of the heating cigarette is significantly higher than that of the quartz tube, and therefore stainless steel is not suitable to be used as the filter material of the heating cigarette alone.

[0073] The above describes the exemplary embodiments of the present application. However, the protection scope of the present application is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made by those skilled in the art within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A cigarette filter, the filter having a first end and a second end in its extending direction, the filter comprising a main body and a smoke flow hole disposed in the main body, the smoke flow hole having a continuous through-hole for gas to flow between the first end and the second end, the main body comprising a first main material, the first main material having a specific heat capacity of 700-1110 J / kg·K between 0-100°C, a thermal conductivity of 1-5 W / m·K, and a coefficient of linear expansion of 3×10⁻⁶. -7 -8×10 -6 / ℃.

2. The filter tip according to claim 1, wherein, The first main material includes one or more of quartz, silicate ceramics, and borosilicate glass.

3. The filter tip according to claim 1 or 2, wherein, The porosity of the main body is 5%-30%.

4. The filter tip according to any one of claims 1 to 3, wherein, The main body is a tubular main body, and the through hole of the tubular main body is a flue gas flow hole.

5. The filter tip according to claim 4, wherein, The tubular main body has a circular cross-section along the direction perpendicular to the extension.

6. The filter tip according to claim 4 or 5, wherein, The inner wall of the tubular main body has a rough surface, preferably with a roughness Ra of 1.5 μm to 12.5 μm.

7. The filter tip according to any one of claims 4 to 6, wherein, The wall thickness of the tubular main body is 1.0-1.5 mm, and / or the length is 33-45 mm.

8. The filter tip according to any one of claims 1 to 3, wherein, The flue gas flow hole includes one or more channels extending spirally along the extension direction; or, the flue gas flow hole includes multiple parallel through holes; or, the inner wall of the flue gas flow hole is provided with protrusions.

9. The filter tip according to any one of claims 1 to 3, wherein, The cross-sectional area of ​​the flue gas flow hole gradually increases from the first end to the second end, and / or the inner wall of the flue gas flow hole is provided with a hydrophilic coating or pores.

10. The filter tip according to any one of claims 1 to 9, wherein, The main body also includes a second main material, which has a specific heat capacity of 300-600 J / kg·K between 0-100℃, a thermal conductivity of 15-20 W / m·K, and a coefficient of linear expansion of 10×10⁻⁶. -6 -15×10 -6 / ℃, the first main material and the second main material are inlaid or alternately arranged along the extension direction.

11. The filter tip according to claim 10, wherein, At least the second end of the main body is the first main material, and the length of the first main material located at the second end is 3 mm-8 mm.

12. The filter tip according to claim 10 or 11, wherein, The second main material is one or more of stainless steel, copper alloy, aluminum, or graphene-based thermally conductive composite materials.

13. A heat-not-burn cigarette, comprising a cigarette core material and a filter, wherein, The filter tip includes the filter tip according to any one of claims 1 to 12, wherein the material of the end of the filter tip away from the cigarette core material is a first main material.

Images