A hollow metal tube filled with phase change cooling material for heated non-combustible cigarettes and heated non-combustible cigarettes.

Abstract

This invention discloses a hollow metal tube filled with phase change cooling material for heated non-combustible cigarettes, and the heated non-combustible cigarette itself. The heating non-combustible cigarette includes a hollow metal tube and a phase change cooling material. The phase change cooling material is filled and sealed inside the hollow metal tube. The hollow metal tube filled with the phase change cooling material is placed inside the heated non-combustible cigarette in at least one of the following ways: winding, folding, gathering, or bending, to form a cooling unit. The cooling unit has a longitudinally extending smoke channel; the longitudinal direction of the cooling unit has a porosity of 40%-90%. The hollow metal tube filled with phase change cooling material cooling unit of this invention has the advantages of high latent heat of phase change, low thermal hysteresis effect, high heat absorption efficiency, apparent stability without collapse, and no leakage.

Description

Technical Field

[0001] This invention belongs to the field of cigarette materials, specifically relating to a heating non-combustible cigarette cooling unit filled with a hollow metal tube and a heating non-combustible cigarette. Background Technology

[0002] Existing e-cigarettes are relatively mature, offering good atomization and a wide variety, but their safety remains a concern. In contrast, heated tobacco products, due to their different heating method compared to traditional cigarettes, can provide a healthier smoking experience while satisfying consumers' sensory needs. Heated tobacco products involve inserting tobacco into a heating device, which then heats the tobacco to release nicotine and other aromatic substances. Heated tobacco products are gaining increasing popularity in the market, with various tobacco companies launching their own products.

[0003] However, the large-scale promotion of heated tobacco products still faces many problems. On the one hand, the heating temperature of heated tobacco products is 200-380℃, which prevents some flavor compounds from being fully released, resulting in an unsatisfactory taste. On the other hand, heated tobacco cigarettes are generally shorter, and to ensure the number of puffs, the filter length is also shortened accordingly. Compared to traditional cigarettes, this makes the smoke more prone to overheating during transmission, resulting in excessively high temperatures when the smoke enters the mouth, causing a burning sensation and a strong feeling of heat and dryness, thus affecting the smoking experience. Furthermore, all tobacco companies' products suffer from poor filter cooling performance. Currently, the commonly used cooling material for heated tobacco products is polylactic acid (PLA) film. However, PLA film has poor mechanical strength, is prone to breakage during folding and gathering, and is thermoplastic, easily deformed by heat, causing the cooling unit to collapse. This affects the cooling unit's support performance for the cigarette, and the deformed PLA film can block part of the smoke passage, affecting the cooling effect and reducing the amount of smoke. Furthermore, the cooling effect of gathered PLA film is limited; the smoke temperature after passing through the gathered PLA film still cannot reach a comfortable temperature for the mouth. Existing phase change material cooling systems based on polyethylene glycol (PEG) are prone to leakage when heated during use, summer storage, or outdoor transportation, affecting the appearance and performance of the product and limiting its application in heated tobacco products. Therefore, finding an economical, safe, environmentally friendly cooling unit with stable cooling performance and quality, and further improving the smoking experience of heated tobacco products, remains a pursuit in this technical field. Summary of the Invention

[0004] The present invention adopts the following technical solution to solve the above problems:

[0005] A cooling unit for heated non-combustible cigarettes filled with a hollow metal tube and a phase change cooling material is disclosed. The hollow metal tube is filled and sealed within the hollow metal tube. The hollow metal tube filled with the phase change cooling material is placed inside the heated non-combustible cigarette by at least one of the following methods: winding, folding, gathering, or bending, forming a longitudinally extending smoke channel to form the cooling unit. The cooling unit has a porosity of 40%-90% along the longitudinal direction of the cigarette strip. The phase change cooling material comprises 55-96 parts by weight of polyethylene glycol, 1-5 parts by weight of in-situ reinforcing material, and 3-40 parts by weight of thermally conductive filler. The polyethylene glycol has a molecular weight of 1500-2500 Da and a melting point of 45-60°C. The in-situ reinforcing material is fully dispersed in the polyethylene glycol matrix and provides in-situ physical reinforcement; it is selected from cellulose acetate or polylactic acid with a molecular weight of 50,000-150,000.

[0006] In this invention, the term "longitudinal direction" refers to the direction extending along the column axis of the cigarette bar or parallel to the column axis of the bar.

[0007] Furthermore, the outer diameter of the hollow metal tube is preferably 0.1-1 mm.

[0008] In this invention, the outer diameter of the hollow metal tube refers to the dimension at the widest point of the hollow metal tube's cross-section.

[0009] In this invention, the cross-sectional shape of the hollow metal tube is not limited. It can have a regular geometric configuration or an irregular configuration (such as a shaped tube). A regular geometric configuration is preferred to facilitate subsequent processing and folding. The regular geometric configuration includes, but is not limited to, circles, ellipses, oval shapes, polygons, rounded polygons, serrations, and stars. The hollow metal tube formed includes, but is not limited to, round tubes, elliptical tubes, oval tubes, polygonal tubes, rounded polygonal tubes, serrated tubes, and star-shaped tubes. More preferably, round tubes, square tubes, and hexagonal tubes are used, with round tubes being the most preferred.

[0010] In this invention, the cross-sectional shape of the inner hole of the hollow metal tube is not limited. It can have a regular geometric configuration or an irregular configuration. It is preferred to have a regular geometric configuration to facilitate the filling of phase change cooling material. The regular geometric configuration includes, but is not limited to, circles, ellipses, oval shapes, polygons, rounded polygons, tooth shapes, and star shapes. More preferably, circles, squares, and hexagons are used, and circles are the most preferred.

[0011] In this invention, the oval shape refers to a closed shape formed by dividing a circle into two semicircular arcs through the center and translating them in opposite directions, and connecting the endpoints of the two semicircular arcs with two parallel lines of equal length.

[0012] In this invention, the polygon refers to a planar figure composed of three or more line segments connected end to end in sequence, such as triangles, rectangles, pentagons, and hexagons.

[0013] In this invention, the term "rounded polygon" refers to a polygon whose corners have a certain degree of roundness.

[0014] In this invention, the tooth profile refers to a closed shape resembling a gear tooth profile.

[0015] In this invention, the star shape refers to a closed shape resembling a star, such as a pentagram, a hexagon, or other multi-pointed star.

[0016] In one embodiment of the present invention, the hollow metal tube is selected from stainless steel capillary tubes, copper-based capillary tubes, aluminum-based capillary tubes, titanium-based capillary tubes, and nickel-based capillary tubes.

[0017] In this invention, the metal-based capillary refers to a metal tube with an outer diameter of 0.1-1 mm made of the metal or an alloy material mainly composed of the metal. For example, copper-based capillary includes capillary tubes made of pure copper, as well as capillary tubes made of copper alloys such as brass, bronze, and cupronickel.

[0018] In one embodiment of the present invention, the hollow metal tube is formed by winding and folding metal foil.

[0019] Furthermore, the metal foil is selected from gold foil, silver foil, copper foil, aluminum foil, zinc foil, and tin foil, with aluminum foil being more preferred due to its high cost-effectiveness.

[0020] In this invention, the hollow metal tube filled with phase change cooling material has a certain strength, which is beneficial for good shaping during the process of forming the cooling unit by winding, folding, gathering, and bending. This ensures the formation of a longitudinally extending channel, increases the effective heat exchange area of ​​the cooling unit, and thus improves the heat deformation resistance of the cooling unit and even the entire cigarette. The metal tube with good thermal conductivity can also play a good role in heat conduction, which is beneficial for the transfer and dissipation of heat between the cooling unit and the phase change cooling material during the use of the cigarette, and plays a directional heat conduction role.

[0021] In this invention, the polyethylene glycol, as a phase change material, can absorb heat and undergo an isothermal phase change (energy storage process) when the temperature is above the phase change point, and undergo a reverse phase change (energy release process) when the temperature is below the phase change point, thus exhibiting strong energy storage and temperature control capabilities. Utilizing the heat storage or release property of polyethylene glycol, it can be used to control or regulate the temperature of the working source or the environment surrounding the material, thereby achieving its specific application functions.

[0022] In this invention, the polyethylene glycol has a molecular weight of 1500-2500 Da and a melting point of 45-60℃. During its solid-to-liquid phase transition, it undergoes an endothermic process. When the melting point of the polyethylene glycol in the phase change cooling material is below 45℃, fluid-like substances will diffuse onto the cooling unit during natural storage and outdoor transportation, affecting preservation and use. When the melting point is above 60℃, the viscosity of the polyethylene glycol in the molten state increases, and the hardness after solidification is too high, reducing the stability of the preparation process and its quality. Selecting polyethylene glycol with this molecular weight distribution and melting point range ensures that it possesses a certain consistency. Combined with in-situ reinforcing materials and thermally conductive fillers, this effectively mitigates deformation and flow within the cooling unit during natural storage and outdoor transportation of the phase change cooling material. Simultaneously, it ensures good fluidity at processing temperatures, appropriate viscosity and hardness after cooling, and overall stable preparation process and quality. Furthermore, through extensive experiments by the inventors, polyethylene glycol with this molecular weight and melting point range was selected. When blended with in-situ reinforcing materials and thermally conductive fillers, the resulting phase change cooling material has a phase change temperature range that falls within the suitable range of 45-60℃, exhibiting high heat absorption efficiency. As a cigarette cooling unit, it has a good heat absorption and cooling effect.

[0023] In one embodiment of the present invention, cellulose acetate is selected as an in-situ reinforcing material. As an in-situ reinforcing material, cellulose acetate can be uniformly dispersed in the polyethylene glycol matrix, playing an in-situ reinforcing role of the fiber. Furthermore, the fiber structure distributed in the polyethylene glycol also hinders the flow of polyethylene glycol during thermal phase change, alleviating the flow and leakage of polyethylene glycol.

[0024] In one embodiment of the present invention, polylactic acid with a molecular weight of 50,000 to 150,000 is selected as an in-situ reinforcing material. Polylactic acid with this molecular weight can be melt-blended with polyethylene glycol without phase separation when heated, and dispersed in the polyethylene glycol matrix when cooled due to its high molecular weight, acting as a physical rivet, thereby reinforcing the polyethylene glycol matrix in situ and hindering the flow of polyethylene glycol during thermal phase change, thus alleviating the flow and leakage of polyethylene glycol.

[0025] In this invention, the thermally conductive filler is selected from alumina, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide, silicon dioxide, molybdenum disulfide, thermally conductive carbon powder, thermally conductive graphite, and graphene; the thermally conductive filler can be selected from micron-sized or nano-sized materials. The thermally conductive filler in the phase change cooling material can greatly improve the heat transfer capacity of the polymer matrix, constructing a continuous and uniform heat transfer network, thereby facilitating heat diffusion and achieving a good cooling effect. It also plays a certain role in reinforcement and physical anti-flowing.

[0026] Furthermore, the thermally conductive filler is selected from alumina, aluminum nitride, boron nitride, thermally conductive graphite, and graphene, which have high thermal conductivity.

[0027] In a preferred embodiment of the present invention, the amount of thermally conductive filler added is 10-20 parts by weight.

[0028] Furthermore, the phase change cooling material is filled with 60%-100% of the hollow metal tube, preferably 80%-100%. This appropriate filling rate ensures that the phase change cooling material effectively absorbs and cools the product during use. The hollow metal tube itself, acting as a thermally conductive substrate, rapidly conducts heat to the phase change cooling material when the cooling unit is heated, and then quickly conducts and dissipates the phase change heat after the phase change cooling material is heated, thus achieving excellent heat conduction and dissipation. In addition, the phase change cooling material in this invention is filled and sealed within the hollow metal tube, effectively solving the leakage problem of polyethylene glycol in the phase change cooling material.

[0029] In specific embodiments of the present invention, the phase change cooling material can be filled into a hollow metal tube by methods such as high-pressure vacuum filling or wrapping filling. When the hollow metal tube is selected from metal-based capillaries, high-pressure vacuum filling is preferred for filling the phase change cooling material. During this process, the phase change cooling material can be appropriately heated to improve the filling rate. When the hollow metal tube is formed by winding and folding metal foil, wrapping filling is preferred for filling the phase change cooling material. In this process, the phase change cooling material can first be made into filaments of 0.1-1 mm thickness using hydrostatic pressing or extrusion, then wound, folded, and wrapped with metal foil, cut to the required length, and then sealed with an adhesive.

[0030] In specific embodiments of the present invention, the hollow metal tube can be sealed by methods such as heat extrusion, welding, adding sealant, and applying adhesive. When the hollow metal tube is selected from metal-based capillary tubes, heat extrusion, welding, and adding sealant are preferred methods for sealing the metal tube. When the hollow metal tube is formed by winding and folding metal foil, adding sealant and applying adhesive are preferred methods for sealing the metal tube.

[0031] In this invention, the heating and extrusion involves fixing the hollow metal tube and heating it at a high temperature, then extruding and deforming the softened metal tube end to form a sealed end.

[0032] In this invention, the hollow metal tube filled with phase change cooling material is placed inside the heated non-combustible cigarette in a winding, folding, gathering, and bending manner to form a longitudinally extending channel. The hollow metal tube plays a supporting and shaping role, thereby ensuring that the smoke has a certain throughput in the cooling unit, greatly increasing the effective heat exchange area, preventing the problem of reduced cigarette smoke concentration and increased draw resistance, and providing consumers with a good smoking experience. In addition, when the smoke passes through the longitudinally extending channel, the hollow metal tube and the phase change cooling material inside can be heated evenly, thereby achieving a good cooling effect.

[0033] In a specific embodiment of the present invention, the winding, folding, gathering, and bending methods and the density of the hollow metal tube filled with phase change cooling material can be adjusted according to actual needs, so as to form a longitudinally extending channel in the non-combustible cigarette and have a suitable porosity along the longitudinal direction of the cigarette bar, which is more conducive to the heat dissipation and cooling of the smoke in the cooling unit, and avoids the problems of excessively high filter unit temperature and hot cooling unit.

[0034] In this invention, the hollow metal tube cooling unit for heated, non-combustible cigarettes filled with phase change cooling material preferably has a porosity of 40%-90% along the longitudinal direction of the cigarette bar. Adjusting the porosity appropriately ensures normal flow of smoke within the cooling unit and achieves a good and stable cooling effect. In this invention, the porosity of the heated, non-combustible cigarette cooling unit is further preferably 60%-90%.

[0035] In this invention, the porosity refers to the percentage of the cross-sectional area perpendicular to the longitudinal direction occupied by the through holes in the cooling unit.

[0036] In this invention, the length of the heating non-combustible cigarette cooling unit filled with phase change cooling material in the hollow metal tube is between 7-28 mm.

[0037] In this invention, the phase change cooling material has a phase change temperature range of 45-60℃ and a phase change enthalpy greater than 80J / g. These values ​​can be obtained by measuring the phase change temperature and phase change enthalpy of the phase change cooling material using a differential scanning calorimeter.

[0038] In this invention, the hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes absorbs more than 2J of heat during use.

[0039] In this invention, the phase change cooling material is prepared through the following steps:

[0040] Thermally conductive filler is added to polyethylene glycol and heated to 60-80℃ and mixed evenly to obtain a premix. Then, a phase change cooling material is obtained by method (1) or method (2). Method (1) uses cellulose acetate as an in-situ reinforcing material, dissolves it in an organic solvent and mixes it evenly with the premix, and then removes the solvent to obtain the phase change cooling material. Method (2) uses polylactic acid as an in-situ reinforcing material, heats it with the premix to 120-230℃ and mixes it evenly, and then cools it to obtain the phase change cooling material.

[0041] The organic solvent used may be selected from one or a mixture of two of the following: ethanol, diethyl ether, acetone, tetrahydrofuran, dichloromethane, chloroform, methyl acetate, and dimethylformamide, or a mixture thereof in any proportion. Acetone, a low-boiling-point organic solvent, is preferred.

[0042] In this invention, the mixing method can be selected from mechanical stirring, magnetic stirring, or ultrasound. During the mixing process, appropriate heating can be used to promote the mixing between components.

[0043] The present invention also discloses a heated non-combustible cigarette, which includes a smoke-generating unit (1), a hollow isolation unit (2), a heated non-combustible cigarette cooling unit (3) filled with phase change cooling material in a hollow metal tube as described above, a filter unit (4), and a packaging unit (5) for wrapping the above units.

[0044] In this invention, the smoke-generating unit (1) is formed by vertically arranging and gathering strips or sheets of tobacco material, with irregular air pores densely distributed between the tobacco materials. The tobacco material may be selected from one or more of vanilla leaves, tobacco leaves, tobacco rib fragments, tobacco sheets, homogenized tobacco, extruded tobacco, and expanded tobacco, as well as powders, granules, pellets, fragments, spaghetti-like pieces, strips, or sheets.

[0045] In this invention, the packaging unit (5) is composed of cigarette paper, forming paper, and tipping paper.

[0046] In this invention, the total length of the heated non-combustible cigarette is between 40 and 95 mm.

[0047] The beneficial effects of this invention are as follows:

[0048] 1. The phase change cooling material used in this invention has the characteristics of high latent heat of phase change, low thermal hysteresis effect, high heat absorption efficiency, non-toxicity, non-irritation, and stable performance. It has a certain consistency and good processability, and is not prone to deformation and flow during natural storage and outdoor transportation. As a cigarette cooling unit, it has a good heat absorption and cooling effect. In addition, the physical barrier network formed by the uniformly dispersed in-situ reinforcing material and thermally conductive filler in the phase change cooling material not only reinforces the polyethylene glycol matrix in situ, improving the mechanical properties of the cooling unit and preventing it from collapsing due to heat, but also inhibits the flow of polyethylene glycol during thermal phase change. It also has a blocking effect on the diffusion of harmful substances produced by tobacco combustion, reducing the intake of harmful substances by the human body. Thus, a continuous and uniform heat transfer, barrier, and reinforcing network is constructed, which reduces the temperature of cigarette smoke and greatly enhances the practical value of the phase change material cooling system for heated non-combustible cigarettes.

[0049] 2. The heated non-combustible cigarette cooling unit of this invention is constructed from a hollow metal tube filled and sealed with phase change cooling material, possessing excellent support and thermal conductivity. The hollow metal tube filled with phase change cooling material has a certain strength, facilitating proper shaping during the formation of the cooling unit through winding, folding, gathering, and bending. This ensures the formation of longitudinally extending channels, increasing the effective heat exchange area of ​​the cooling unit and thus improving the resistance to thermal deformation of the cooling unit and even the entire cigarette. The metal tube itself, with its good thermal conductivity, also plays a good role in heat conduction, facilitating the transfer and dissipation of heat between the cooling unit and the phase change cooling material during cigarette use, thus providing directional heat conduction. The organic combination of the hollow metal tube and the phase change cooling material allows the hollow metal tube itself, as a heat-conducting substrate, to rapidly conduct heat to the phase change cooling material when the cooling unit is heated, and then rapidly conduct and dissipate the phase change heat after the phase change cooling material is heated, thereby achieving excellent thermal conductivity and heat dissipation. Furthermore, the phase change cooling material in this invention is filled and sealed inside a hollow metal tube, which effectively solves the problem of polyethylene glycol leakage faced when the phase change cooling material is directly coated on the carrier. Moreover, the phase change cooling material can maintain a high filling rate inside the hollow metal tube, thereby fully utilizing the heat absorption and cooling effect of the phase change cooling material of this invention.

[0050] 3. In this invention, the hollow metal tube containing phase change cooling material is placed inside the heated non-combustible cigarette in a winding, folding, gathering, and bending manner, forming a longitudinally extending smoke channel. The hollow metal tube plays a supporting and shaping role, thereby ensuring that the smoke has a certain throughput in the cooling unit, greatly increasing the effective heat exchange area, preventing the problem of reduced cigarette smoke concentration and increased draw resistance, and providing consumers with a good smoking experience. In addition, when the smoke passes through the longitudinally extending channel, the hollow metal tubes in each area and the phase change cooling material inside can be heated evenly, thereby obtaining a good cooling effect.

[0051] 4. The phase change cooling material in the heating non-combustible cigarette cooling unit of the present invention, which is filled with hollow metal tubes, has a suitable phase change temperature (45-60℃) and a high phase change enthalpy (greater than 80J / g). It has a higher latent heat of phase change per unit mass, realizing a truly practical phase change heat absorption with high heat absorption efficiency. When used as a cigarette cooling unit, it has a good heat absorption and cooling effect. During use, the average temperature of the smoke is reduced by 12-18℃ compared with existing domestic products, effectively reducing the burning sensation of smoke in the mouth and improving the smoking experience of heating non-combustible cigarettes.

[0052] 5. The heated non-combustible cigarette sample of this invention has an intact appearance and does not collapse during use, and there is no leakage on the surface. It solves the problems of poor mechanical strength, easy breakage during the gathering and folding process, easy deformation and collapse when heated, and partial blockage of the smoke passage by polylactic acid film as a cooling material, as well as the leakage problem of polyethylene glycol phase change material system. Attached Figure Description

[0053] Figure 1 The diagram shows the structure of the heated non-combustible cigarette in the embodiment; wherein, (1) is the smoke generating unit, (2) is the hollow isolation unit, (3) is the heated non-combustible cigarette cooling unit filled with phase change cooling material in a hollow metal tube, (4) is the filter unit, and (5) is the packaging unit;

[0054] Figure 2 This is a comparison chart of the DSC test results of the phase change cooling materials used in Comparative Example 3 and Example 1. Detailed Implementation

[0055] The present invention will be further described in detail below through specific embodiments. Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. Specific processes and equipment not specified in the embodiments are carried out according to the techniques or conditions described or implemented in literature or actual processes and equipment in the art.

[0056] The heated tobacco cooling unit of this embodiment includes a hollow metal tube and a phase change cooling material. The phase change cooling material is filled and sealed inside the hollow metal tube. The hollow metal tube filled with the phase change cooling material is placed inside the heated tobacco product in at least one of the following ways: winding, folding, gathering, or bending to form the cooling unit. (Reference) Figure 1 The resulting heated tobacco product comprises a smoke-generating unit 1, a hollow isolation unit 2, a heated tobacco cooling unit 3 filled with phase change cooling material in a hollow metal tube, a filter unit 4, and a packaging unit 5 used to wrap the aforementioned units, all assembled sequentially in the form of a bar. As an example, the hollow metal tube filled with phase change cooling material is bent to form a shape that spirals longitudinally with the longitudinal axis as the axis, and the remaining space forms the smoke channel.

[0057] Example 1

[0058] 15 parts by weight of boron nitride were added to 80 parts by weight of polyethylene glycol 2,000, and the mixture was heated to 65°C and mixed thoroughly to obtain a premix. 5 parts by weight of cellulose acetate were dissolved in acetone and mixed thoroughly with the premix. The mixture was then placed in an oven at 40°C to remove the solvent and cooled to obtain a phase change cooling material.

[0059] The prepared phase change cooling material was heated and then filled into a commercially available copper capillary tube (200 mm in length, approximately 0.5 mm in outer diameter) using a high-pressure vacuum filling method, with a filling amount of approximately 18 mg. The ends were then sealed with metal sealant. The copper capillary tube filled with the phase change cooling material was then wound and folded to form the heated non-combustible cigarette cooling unit. The prepared heated non-combustible cigarette cooling unit was used to prepare heated non-combustible cigarette samples, and its performance was tested.

[0060] Example 2

[0061] 15 parts by weight of boron nitride were added to 81 parts by weight of polyethylene glycol 2,000, and the mixture was heated to 65°C and stirred until homogeneous to obtain a premix. 4 parts by weight of polylactic acid (Hubei Xinyuhong, molecular weight 100,000) were added to the premix and heated to 200°C, stirred until homogeneous, and then cooled to obtain the phase change cooling material.

[0062] The prepared phase change cooling material was heated and then filled into a commercially available stainless steel capillary square tube (200 mm in length, with a cross-sectional dimension of approximately 0.4 mm × 0.4 mm) using a high-pressure vacuum filling method. The filling amount was approximately 30 mg, and the ends were then sealed with metal sealant. The stainless steel capillary square tube filled with the phase change cooling material was then wound and folded to form the heated non-combustible cigarette cooling unit. The prepared heated non-combustible cigarette cooling unit was used to prepare heated non-combustible cigarette samples, and its performance was tested.

[0063] Example 3

[0064] Ten parts by weight of boron nitride were added to 86 parts by weight of polyethylene glycol 2,000, and the mixture was heated to 65°C and stirred until homogeneous to obtain a premix. Four parts by weight of polylactic acid (Hubei Xinyuhong, molecular weight 100,000) were added to the premix and heated to 200°C and stirred until homogeneous. The mixture was then cooled to obtain the phase change cooling material.

[0065] Phase change cooling material was made into filaments approximately 0.3 mm in thickness using a hydrostatic pressing method. These filaments were then wrapped and folded with aluminum foil strips measuring 200 mm × 2 mm, and finally cut and sealed with adhesive. The aluminum foil tubes filled with phase change cooling material were then wound and folded to form the heated tobacco cooling unit. The prepared heated tobacco cooling unit was used to prepare heated tobacco samples, and its performance was tested.

[0066] Example 4

[0067] Ten parts by weight of graphene were added to 87 parts by weight of polyethylene glycol 2,000, and the mixture was heated to 65°C and mixed thoroughly to obtain a premix. Three parts by weight of cellulose acetate were dissolved in acetone and mixed thoroughly with the premix. The mixture was then placed in an oven at 40°C to remove the solvent and cooled to obtain a phase change cooling material.

[0068] Phase change cooling material was made into filaments approximately 0.3 mm in thickness using a hydrostatic pressing method. These filaments were then wrapped and folded with aluminum foil strips measuring 200 mm × 2 mm, and finally cut and sealed with adhesive. The aluminum foil tubes filled with phase change cooling material were then wound and folded to form the heated tobacco cooling unit. The prepared heated tobacco cooling unit was used to prepare heated tobacco samples, and its performance was tested.

[0069] Example 5

[0070] 20 parts by weight of alumina were added to 75 parts by weight of polyethylene glycol 2,500, and the mixture was heated to 70°C and stirred until homogeneous to obtain a premix. 5 parts by weight of cellulose acetate were dissolved in acetone and mixed with the premix until homogeneous. The mixture was then placed in an oven at 40°C to remove the solvent and cooled to obtain a phase change cooling material.

[0071] Phase change cooling material was made into filaments approximately 0.3 mm in thickness using a hydrostatic pressing method. These filaments were then wrapped and folded with aluminum foil strips measuring 200 mm × 2 mm, and finally cut and sealed with adhesive. The aluminum foil tubes filled with phase change cooling material were then wound and folded to form the heated tobacco cooling unit. The prepared heated tobacco cooling unit was used to prepare heated tobacco samples, and its performance was tested.

[0072] Example 6

[0073] 20 parts by weight of thermally conductive graphite were added to 75 parts by weight of polyethylene glycol 1,500, and the mixture was heated to 60°C and mixed evenly to obtain a premix. 5 parts by weight of cellulose acetate were dissolved in acetone solvent and mixed evenly with the premix. The mixture was placed in an oven at 40°C to remove the solvent, and after cooling, a phase change cooling material was obtained.

[0074] The prepared phase change cooling material was heated and then filled into a commercially available copper capillary tube (200 mm in length, approximately 0.5 mm in outer diameter) using a high-pressure vacuum filling method, with a filling amount of approximately 18 mg. The ends were then sealed with metal sealant. The copper capillary tube filled with the phase change cooling material was then wound and folded to form the heated non-combustible cigarette cooling unit. The prepared heated non-combustible cigarette cooling unit was used to prepare heated non-combustible cigarette samples, and its performance was tested.

[0075] Comparative Example 1

[0076] In Example 1, the copper capillary tube was not filled with phase change cooling material as a control sample, and the rest of the preparation method was the same as in Example 1.

[0077] Comparative Example 2

[0078] The cigarettes used are the commercially available Fujian Tobacco Jinqiao brand cigarettes.

[0079] Comparative Example 3

[0080] It uses commercially available Marlboro IQOS cigarettes.

[0081] The phase change temperature and phase change enthalpy of the phase change cooling material of the heated non-combustible cigarette cooling unit in the comparative example and various embodiments of the present invention were tested using a differential scanning calorimeter (DSC200F3, NETZSCH, Germany), and the test results are listed in Table 1.

[0082] The heated tobacco products in each comparative example and embodiment were simulated for smoking according to the cigarette smoking model specified in the national standard YC / T29-1996. A K-type thermocouple temperature detector was used to measure the temperature at the center of the cigarette filter rod during smoking. The smoke temperature test results corresponding to the number of puffs are listed in Table 2. The highest and lowest smoke temperatures of each comparative example and embodiment were statistically analyzed. The sensory evaluation of the cigarette samples in each comparative example and embodiment was conducted using the YCT138-1998 cigarette sensory evaluation standard, and the results are listed in Table 3. Figure 2 This is a comparison chart of the DSC test results of the phase change cooling materials used in Comparative Example 3 and Example 1 of the present invention.

[0083] Table 1. Phase change temperature and enthalpy of phase change cooling materials in the cooling units of the comparative examples and embodiments of the present invention.

[0084] Phase transition temperature (°C) Phase transition enthalpy (J / g) Comparative Example 3 69.3 11.23 Example 1 53.2 84.15 Example 2 55.7 85.89 Example 3 58.7 90.26 Example 4 52.7 87.85 Example 5 59.6 81.77 Example 6 51.5 103.28

[0085] Table 2. Flue Gas Temperature Test Results of Comparative Examples and Embodiments of the Present Invention

[0086] Number of mouths 1 2 3 4 5 6 7 8 Comparative Example 1 61.4 62.2 63.2 63.1 62.1 62.0 60.8 59.7 Comparative Example 2 54.2 62.0 60.5 57.3 54.4 53.1 53.2 53.1 Comparative Example 3 46.4 50.7 51.9 48.9 45.9 43.3 41.4 40.4 Example 1 39.2 44.0 44.2 41.1 40.6 38.1 37.8 36.2 Example 2 38.0 45.6 44.9 44.4 42.6 38.9 35.5 35.2 Example 3 41.5 48.4 47.9 46.1 44.7 40.3 39.3 38.4 Example 4 42.0 48.3 49.2 47.1 46.9 41.7 39.2 38.4 Example 5 43.8 48.7 49.8 48.4 45.9 43.5 41.8 40.3 Example 6 39.6 46.1 46.7 44.9 43.8 38.8 37.4 36.5

[0087] Table 3. Comparison of Smoke Temperature Test Results and Sensory Evaluation of Cigarettes in the Comparative Example and Embodiment of the Invention

[0088]

[0089]

[0090] The data results from the above sets show that the phase change cooling material in the hollow metal tube-filled heating non-combustible cigarette cooling unit of the embodiment has a more suitable phase change temperature (50-60℃) and a higher phase change enthalpy (greater than 80J / g) compared to Comparative Example 3. It also has a higher latent heat of phase change per unit mass, achieving a truly practical phase change heat absorption. By comparing the data of Comparative Example 1 (without phase change cooling material) and Example 1 (with phase change cooling material), it can be seen that the phase change cooling material of the embodiment has a higher heat absorption efficiency. Using it as a cigarette cooling unit has a good heat absorption and cooling effect, which can reduce the average temperature of the smoke by nearly 20℃.

[0091] The heated tobacco sample prepared using the heated tobacco cooling unit of the embodiment showed significant improvements in oral comfort, smoke irritation, and burning sensation compared to the Fujian Tobacco control sample. The average smoke temperature was reduced by 12-18°C, and the overall smoking quality of the cigarette was significantly improved. Compared to Philip Morris's Marlboro cigarettes, the heated tobacco sample of the embodiment also exhibited superior cooling performance, with an average smoke temperature reduction of 2-8°C. Furthermore, the heated tobacco sample prepared using the heated tobacco cooling unit of the embodiment remained intact and did not collapse during use, with no leakage. This solved the problems of poor mechanical strength, easy breakage during folding and gathering, easy deformation and collapse under heat, and partial blockage of smoke channels by polylactic acid film as a cooling material, as well as the leakage problem of polyethylene glycol phase change material systems.

[0092] The above embodiments illustrate and describe the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A heating and non-combustible cigarette cooling unit filled with a hollow metal tube and a phase change cooling material, characterized in that, The invention comprises a hollow metal tube and a phase change cooling material. The hollow metal tube has an outer diameter of 0.1-1 mm. The phase change cooling material is filled and sealed inside the hollow metal tube. The hollow metal tube filled with the phase change cooling material is placed inside a heated non-combustible cigarette in at least one of the following ways: winding, folding, gathering, or bending, to form a cooling unit. The cooling unit has a longitudinally extending smoke channel. The longitudinal direction of the cooling unit has a porosity of 40%-90%. The phase change cooling material comprises 55-96 parts by weight of polyethylene glycol, 1-5 parts by weight of in-situ reinforcing material, and 3-40 parts by weight of thermally conductive filler. The polyethylene glycol has a molecular weight of 1500-2500. Da, with a melting point of 45-60℃; wherein, the in-situ reinforcing material is selected from cellulose acetate or polylactic acid with a molecular weight of 50,000-150,000; the thermally conductive filler is selected from at least one of alumina, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide, silicon dioxide, molybdenum disulfide, thermally conductive carbon powder, thermally conductive graphite, and graphene.

2. The hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes according to claim 1, characterized in that, The hollow metal tube is selected from round tubes, elliptical tubes, oval tubes, polygonal tubes, rounded polygonal tubes, toothed tubes, or star-shaped tubes.

3. The hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes according to claim 1, characterized in that, The hollow metal tube has a regular geometric shape in its inner hole cross-section, selected from circles, ellipses, oval shapes, polygons, rounded polygons, serrated shapes, or star shapes.

4. The hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes according to claim 1, characterized in that, The hollow metal tube is selected from stainless steel capillary tubes, copper-based capillary tubes, aluminum-based capillary tubes, titanium-based capillary tubes, or nickel-based capillary tubes.

5. The hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes according to claim 1, characterized in that, The hollow metal tube is formed by winding and folding metal foil, which is selected from gold foil, silver foil, copper foil, aluminum foil, zinc foil or tin foil.

6. The hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes according to claim 1, characterized in that, The phase change cooling material has a filling rate of 60%-100% inside the hollow metal tube.

7. The hollow metal tube filled with phase change cooling material for heating non-combustible cigarettes according to claim 1, characterized in that, The phase change cooling material has a phase change temperature range of 45-60℃ and a phase change enthalpy greater than 80J / g.

8. A heated non-combustible cigarette, characterized in that, It includes a smoke-generating unit (1) assembled in sequence in the form of a bar, a hollow isolation unit (2), a heated non-combustible cigarette cooling unit (3) filled with phase change cooling material in a hollow metal tube as described in any one of claims 1-7, a filter unit (4), and a packaging unit (5) used to wrap the above units.

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