An aerosol generating product, preparation method and testing method

Abstract

The present invention provides an aerosol-generating article, a preparation method, and an inspection method for use with an electrically heated aerosol-generating device. The aerosol-generating article includes a smoking section that contains a smoking material therein. The electrically heated aerosol-generating device includes a heating element that can be inserted into the smoking section. The maximum thermal resistance of the heat conduction area of the smoking section #imgabs0# satisfies: #imgabs1##imgabs2# where δ represents the maximum radial heating distance of the smoking section, in m, and λ e represents the effective thermal conductivity of the smoking section, in W / m·K. The aerosol-generating article of the present invention has good heat transfer performance and high heating efficiency.

Description

Technical Field

[0001] The present invention relates to the field of heating without burning, and in particular to an aerosol generating product used together with an electric heating aerosol generating device, and a preparation method and a testing method of the aerosol generating product. Background Art

[0002] With the continuous deepening of research on smoking and health, some scientific studies have shown that most of the substances in cigarettes that are harmful to the human body are produced by the thermal decomposition of tobacco when tobacco is burned. In recent years, a variety of new tobacco products that heat tobacco without burning have appeared one after another. These new tobacco products generate aerosols for consumers to inhale by placing the aerosol-generating products in a matching electric heating aerosol generating device for heating. Since the tobacco combustion link is avoided, the intake of harmful substances by consumers can be reduced. During operation, the heater transfers heat to the tobacco material, and then transfers heat from the tobacco material to the packaging material. Cigarettes use electric heating to generate aerosols. For example, when the heater is inserted from the center of the cigarette to heat the cigarette, there is often a large temperature difference between the inside and the outside. In this way, when the heater heats the cigarette, part of the inside of the cigarette has been carbonized by high temperature, but the external atomizer is not completely atomized, which affects the aerosol release effect and the overall smoking experience of consumers. Therefore, it is necessary to study the radial heat transfer performance of cigarettes, hoping to provide an aerosol-generating product that can achieve the optimization of heat conduction. Summary of the invention

[0003] The present invention provides an aerosol generating product and a preparation method and a testing method of the aerosol generating product, so as to solve the above technical problems.

[0004] An aerosol generating product for use with an electrically heated aerosol generating device, comprising a smoking section containing a smoking material, wherein the electrically heated aerosol generating device comprises a heating element, wherein the heating element can be inserted into the smoking section, and the maximum thermal conductivity area thermal resistance of the smoking section is satisfy: The unit is m 2 K / W, where

[0005] δ: the maximum radial heating distance of the smoking section, in meters, expressed as the distance between the surface of the heating element and the smoking material at the farthest point in the normal direction of the surface;

[0006] λ e : Effective thermal conductivity of the smoke section, in W / m·K, and satisfies: λ e =ελ a +(1-ε)λ s ,in,

[0007] ε: void ratio of the smoking section, which is the ratio of the void volume of the smoking section to the total volume of the smoking section;

[0008] λ a : Thermal conductivity of the gap in the smoke section, in W / m·K;

[0009] λ s : Thermal conductivity of the smoke-generating material in the smoke-generating section, in W / m·K.

[0010] The aerosol generating product adopting the above solution can optimize heat transfer, thereby improving heating efficiency and improving aerosol release effect.

[0011] Optionally, the thermal conductivity λ of the smoking material in the smoking section s The thermal conductivity of the smoke-generating material is tested by a thermal constant analyzer at standard atmospheric pressure and room temperature. The thermal conductivity of the gap in the smoke-generating section is a It is the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature.

[0012] Optionally, the thermal conductivity of the smoke section gap λ a is 0.026W / m·K, and the smoke section satisfies:

[0013] Optionally, the smoking section satisfies

[0014] Optionally, the void ratio ε of the smoking section satisfies: Among them, m s V is the mass of the whole piece of smoking material obtained at standard atmospheric pressure and room temperature; s is the volume of the entire smoking material at standard atmospheric pressure and room temperature; m is the mass of the smoking section at standard atmospheric pressure and room temperature; V is the volume of the smoking section at standard atmospheric pressure and room temperature.

[0015] Optionally, the void ratio ε of the smoking section satisfies 0.2<ε<0.6.

[0016] Optionally, the maximum radial heating distance δ of the smoking section is 0.0025 to 0.0028 m.

[0017] Optionally, the thermal conductivity λ of the smoking material in the smoking section s It is 0.07~0.32W / m·K.

[0018] Optionally, the heating element is a central heating element, and the smoking segment is suitable for being centrally heated.

[0019] The present invention provides an aerosol generating system, comprising any one of the above-mentioned aerosol generating products and an electrically heated aerosol generating device suitable for heating the aerosol generating product.

[0020] The present invention also provides a method for preparing an aerosol generating product for use with an electrically heated aerosol generating device, comprising the following steps:

[0021] Prepare a smoking segment that meets the conditions: prepare a smoking material that can generate aerosol by electric heating, assemble the smoking material in the smoking segment, the electric heating aerosol generating device includes a heating element, the heating element can be inserted into the smoking segment, and detect the thermal resistance of the maximum thermal conductivity area of ​​the smoking segment The smoke section is adjusted so that the maximum thermal resistance of the heat conduction area of ​​the smoke section satisfy: The unit is m 2 K / W, where

[0022] δ: the maximum radial heating distance of the smoking section, in meters, expressed as the distance between the surface of the heating element and the smoking material at the farthest point in the normal direction of the surface;

[0023] λ e : Effective thermal conductivity of the smoke section, in W / m·K, and satisfies: λ e =ελ a +(1-ε)λ s ,in,

[0024] ε: void ratio of the smoking section, which is the ratio of the void volume of the smoking section to the total volume of the smoking section;

[0025] λ a : Thermal conductivity of the gap in the smoke section, in W / m·K;

[0026] λ s : Thermal conductivity of the smoke-generating material in the smoke-generating section, in W / m·K;

[0027] The smoking segment that meets the conditions is prepared into the aerosol generating product.

[0028] The method for preparing the aerosol generating product of the present invention is to obtain a thermal resistance of the maximum thermal conductivity area. As a measure during the manufacturing process, it helps to ensure the heat transfer performance of the aerosol generating article.

[0029] Optionally, a thermal constant analyzer is used to test the thermal conductivity of the smoking material under standard atmospheric pressure and room temperature, which is recorded as the thermal conductivity λ of the smoking material in the smoking section. s, test the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature, recorded as the thermal conductivity of the air gap of the smoking section λ a .

[0030] Optionally, the thermal conductivity of the smoke section gap λ a The smoke generating section is prepared to meet the following requirements:

[0031] Optionally, the smoking segment is prepared to satisfy:

[0032] Alternatively, the mass of the entire smoking material obtained at standard atmospheric pressure and room temperature is denoted as m s The volume of the whole smoking material is obtained under standard atmospheric pressure and room temperature, which is recorded as V s ; The mass of the smoking section is obtained under standard atmospheric pressure and room temperature, which is recorded as m; the volume of the smoking section is obtained under standard atmospheric pressure and room temperature, which is recorded as V; the porosity ε of the smoking section is obtained by the following method:

[0033] Optionally, the void ratio ε of the smoking section is adjusted to 0.2<ε<0.6.

[0034] Optionally, the maximum radial heating distance δ of the smoking section is adjusted to 0.0025-0.0028 m.

[0035] Optionally, the thermal conductivity λ of the smoking material in the smoking section s Adjust to 0.07~0.32W / m·K.

[0036] Optionally, the heating element is a central heating element, and the smoking segment is prepared to be suitable for being centrally heated.

[0037] The present invention also provides a method for testing an aerosol-generating product, wherein the aerosol-generating product is used together with an electrically heated aerosol-generating device, wherein the aerosol-generating product comprises a smoking segment containing a smoking material, and the electrically heated aerosol-generating device comprises a heating element, wherein the heating element can be inserted into the smoking segment, and the testing steps comprise:

[0038] The porosity of the smoking section is obtained, which is recorded as ε. The porosity of the smoking section is the ratio of the volume of the voids in the smoking section to the total volume of the smoking section. The thermal conductivity of the voids in the smoking section is obtained as λ. a , in units of W / m·K; obtain the thermal conductivity λ of the smoking material in the smoking section s , the unit is W / m·K; the effective thermal conductivity of the smoke section is calculated by the formula, recorded as λ e , the unit is W / m·K, where the formula is λe =ελ a +(1-ε)λ s ;

[0039] Obtain the distance between the surface of the heating element and the farthest smoking material in the normal direction of the surface, which is recorded as the maximum radial heating distance δ of the smoking section, in m; divide the maximum radial heating distance δ of the smoking section by the effective thermal conductivity λ of the smoking section e , get the maximum thermal resistance of the thermal conductivity area, unit is m 2 K / W;

[0040] Check the thermal resistance of the maximum thermal conductivity area Whether it meets:

[0041] The present invention proposes a new aerosol generating product inspection method, by measuring the maximum thermal conductivity area thermal resistance Whether it is within the range is used as the basis for testing the heat transfer performance of aerosol generating products, and provides a reliable standard for preparing aerosol generating products with excellent heating effect and aerosol release effect.

[0042] Optionally, the thermal conductivity λ of the gap in the smoking section is obtained a It includes testing the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature, which is recorded as the thermal conductivity of the air gap of the smoking section λ a ,; obtain the thermal conductivity λ of the smoking material in the smoking section s The thermal conductivity of the smoking material under standard atmospheric pressure and room temperature is measured by a thermal constant analyzer, which is recorded as the thermal conductivity of the smoking material in the smoking section λ s .

[0043] Optionally, if the maximum thermal conductivity area thermal resistance satisfy: The aerosol generating product containing the smoking segment or the smoking segment is judged to be qualified, otherwise it is unqualified. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A schematic diagram of a radial cross section of a smoking section in a specific embodiment of the present invention is shown;

[0045] Figure 2 A schematic diagram of a radial cross-section of a smoke-generating section in another specific embodiment of the present invention is shown. DETAILED DESCRIPTION

[0046] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may extend based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0047] The term "smoking segment" is used herein to describe the product comprising a smoking material, which can be heated to produce an aerosol and delivered to a consumer. The term "smoking material" means a substrate that can release volatile compounds to generate an aerosol when heated. During use, volatile compounds are released from the smoking material by heat transfer. The smoking segment can be a solid smoking segment. The smoking material can include a tobacco-containing material that contains volatile tobacco flavor compounds released from the substrate after heating. The smoking material can include non-tobacco materials. The smoking segment can include an aerosol former. The aerosol former can include at least one of glycerol and propylene glycol. In the embodiment where the smoking material is solid, the solid smoking material can include one or more of: powder, granule, pellet, fragment, through-core tube, strip or sheet, wherein containing one or more of: herbaceous plant leaf, tobacco leaf, tobacco rib sheet, reconstituted tobacco, homogenized tobacco, extruded tobacco and expanded tobacco. The solid smoking material can be in loose form. The smoking segment can include a rod of a solid smoking material. A wrapping material may surround the rod of the solid smoking segment, the wrapping material comprising paper.

[0048] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0049] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0050] The present embodiment provides an aerosol generating product for use with an electrically heated aerosol generating device. The aerosol generating product includes a smoking segment, the interior of which contains a smoking material. The electrically heated aerosol generating device includes a heating element, which can heat the smoking segment by inserting it into the smoking segment, thereby generating an aerosol, such as nicotine smoke. The aerosol generating product of the present embodiment can be, for example, a solid cigarette cartridge, or a cigarette comprising a filter segment and a smoking segment. The smoking segment of the present embodiment can further be a cylindrical smoking segment. The smoking material can specifically be a tobacco material.

[0051] The smoke section of this embodiment meets the following conditions: the maximum heat conduction area thermal resistance of the smoke section satisfy: The unit is m 2 ·K / W. Wherein, δ is the maximum radial heating distance of the smoking section, in m, which is expressed as the distance between the surface of the heating element and the farthest smoking material in the normal direction of the surface. λ e It is the effective thermal conductivity of the smoke section, and its unit is W / m·K.

[0052] The study found that the heating efficiency of the smoke section is related to the thermal resistance of the maximum heat conduction area. There is a significant negative correlation. At the same time, considering the problem of avoiding the burning smell or uneven heating of the smoke-generating material caused by heat concentration, the inventor found through research and summary that the maximum thermal conductivity area thermal resistance satisfy: This situation can ensure that the smoking section can have a suitable heat conduction effect when the heating element is inserted and heated, and the heating efficiency can be significantly improved within the above range.

[0053] Among them, the effective thermal conductivity of the smoke section λ e It is calculated by the following formula: e =ελ a +(1-ε)λ s ε is the void ratio of the smoking section, which is the ratio of the void volume of the smoking section to the total volume of the smoking section. a is the thermal conductivity of the gap in the smoke section, in W / m·K; s It is the thermal conductivity of the smoke-generating material in the smoke-generating section, and its unit is W / m·K.

[0054] λ s and λ a The thermal conductivity of the smoke-generating material in the smoke-generating section is obtained by measuring sThe thermal conductivity of the smoking material under standard atmospheric pressure and room temperature is tested by a thermal constant analyzer, wherein the device used is a thermal constant analyzer Hot Disk TPS2500S. The thermal conductivity of the smoking material in this embodiment is 0.07-0.32 W / m·K. The thermal conductivity of the smoking material within this range can have a suitable thermal conductivity and aerosol release effect. The thermal conductivity of the gap in the smoking section λ a is the thermal conductivity of the air gap between the smoking materials at standard atmospheric pressure and room temperature. a It is about 0.026W / m·K, that is, the thermal resistance of the maximum thermal conductivity area satisfies

[0055] Furthermore, the smoking section includes the smoking material and the air gap between the smoking materials. The porosity ε of the smoking section is determined by the following method: Under standard atmospheric pressure and room temperature, a whole piece of smoking material of a certain mass is taken, and its mass is calculated as m s , the volume is V s , the density is Under standard atmospheric pressure and room temperature, weigh a certain amount of smoking segments made of the same smoking material, calculate its mass as m, volume as V, and the volume of the smoking material contained in the smoking segment is The void ratio ε of the smoke section is Furthermore, in the above embodiments, the porosity ε of the smoking section satisfies 0.2<ε<0.6. The porosity in this range can ensure the heating efficiency of the aerosol generating product and keep the heat transfer rate within a controllable range during heating, thereby ensuring aerosol release and avoiding uneven heating. Preferably, the porosity of the smoking section satisfies 0.25<ε<0.55.

[0056] Furthermore, the smoke section satisfies The heating efficiency is better, preferably, the smoke section meets Within the preferred range, more complete and uniform heating of the tobacco can be achieved.

[0057] More preferably, the smoking section satisfies And the porosity satisfies 0.2<ε<0.6. The porosity affects the dynamic diffusion speed of heat, and the thermal conductivity of the smoking material mainly affects the heat conduction speed.

[0058] In the above embodiments, the maximum radial heating distance δ of the smoking segment is 0.0025 to 0.0028 m. The radial size range of the smoking segment is required to conform to the physiological size of the human lips. If the size is too large, the lips and the mouthpiece will not fit tightly. If the size is too small, it will be difficult to insert the heating element. If the size is too small, less aerosol will be available, limiting the number of puffs. The maximum radial heating distance within the above range can achieve a match between the heat transfer rate and the heat transfer distance, ensuring that the temperature at the peripheral edge of the smoking segment is within a range suitable for releasing aerosols or smoking. Moreover, the maximum radial heating distance of the smoking segment within the above range can ensure that there is still effective release of aerosol components within a predetermined number of puffs. Specifically, refer to Figure 1 and Figure 2 , Figure 1 and Figure 2 Schematic diagram of radial section of smoking segment. In the figure, smoking material 2 is filled inside smoking segment 1, and cigarette paper 4 is wrapped outside smoking segment 1. Heating element 3 is inserted into smoking segment 1 and located at the center of smoking segment. Heating element 3 generates heat in the center of smoking segment, and heat is transferred from the center to the periphery. The radial maximum heating distance δ of smoking segment 1 is the distance between the surface of heating element 3 and the normal direction of heating element 3 surface (e.g. Figure 1 and Figure 2 The normal direction is perpendicular to the plane where the heating element 3 intersects. Figure 1 and Figure 2 Two types of heating elements 3 are shown, namely, a heating needle and a heating sheet.

[0059] The heating element of the heated aerosol generating device is located inside the aerosol generating product when it is working, including a heating needle, a heating plate, etc., and its central axis coincides with the longitudinal axis of the aerosol generating product. The heating element is a central heating element, and the smoking section is suitable for being heated by the center.

[0060] As a preferred embodiment of the present invention, And 0.2<ε<0.6, δ is 0.0025~0.0028m, λ s The temperature is 0.07-0.32 W / m·K, which can achieve the best heating efficiency and aerosol release effect, and the heating is uniform, and the aerosol is uniform and palatable.

[0061] This embodiment also provides an aerosol generating system, including the aerosol generating product of each of the above embodiments, and an electrically heated aerosol generating device suitable for heating the aerosol generating product. The aerosol generating system of this embodiment has the characteristics of high heating efficiency and good aerosol release effect.

[0062] Accordingly, this embodiment also proposes a method for testing an aerosol generating product. The inventor has found through research that, for an aerosol generating product used in conjunction with an electrically heated aerosol generating device, the thermal resistance of the aerosol generating product has an important influence on the heating efficiency. In combination with the characteristics of the aerosol generating product, it is found that the thermal resistance of the smoking section is not only related to the thermal conductivity of the smoking material inside the smoking section, but also the thermal conductivity and porosity of the gaps inside the smoking section, as well as the heating distance within the smoking section. The inventor has obtained a set of parameters that can be used to evaluate the heating efficiency through calculation and experimental attempts. Whether the parameters meet the standards can be matched to evaluate the heating efficiency. The parameters can be used to determine whether the aerosol generating product produced meets the requirements in terms of the utilization rate of the smoking material, the aerosol release effect, and the overall smoking experience of the consumer. In addition, the inventor has also studied and obtained a formula for calculating the parameter and a reasonable range of the parameter, and used the reasonable range of the parameter to test whether the aerosol generating product is qualified as a "gold standard", which provides a reference for evaluating and screening aerosol generating products.

[0063] Specifically, in the inspection method of the aerosol generating product of the present embodiment, the aerosol generating product is used for use with an electrically heated aerosol generating device, the aerosol generating product includes a smoking segment, which contains a smoking material, and the electrically heated aerosol generating device includes a heating element, which can be inserted into the smoking segment. The inspection steps include: obtaining the porosity of the smoking segment, denoted as ε, the porosity of the smoking segment is the ratio of the volume of the voids of the smoking segment to the total volume of the smoking segment; obtaining the thermal conductivity coefficient λ of the voids of the smoking segment a , in units of W / m·K; obtain the thermal conductivity λ of the smoking material in the smoking section s , the unit is W / m·K; the effective thermal conductivity of the smoke section is calculated by the formula, recorded as λ e , the unit is W / m·K, where the formula is λ e =ελ a +(1-ε)λ s ; Obtain the distance between the surface of the heating element and the farthest smoking material in the normal direction of the surface, recorded as the maximum radial heating distance δ of the smoking segment, in m; Divide the maximum radial heating distance δ of the smoking segment by the effective thermal conductivity λ of the smoking segment e , get the maximum thermal resistance of the thermal conductivity area, unit is m 2 ·K / W.

[0064] Define the maximum thermal resistance of the thermal conductivity area as Determine the thermal resistance of the maximum thermal conductivity area Whether it meets: If the conditions are met, the aerosol generating product including the smoking segment is judged to be qualified, otherwise it is unqualified.

[0065] The thermal conductivity λ of the gap in the smoke section is obtained as follows: a It includes testing the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature, which is recorded as the thermal conductivity of the air gap of the smoking section λ a ,; obtain the thermal conductivity λ of the smoking material in the smoking section s The thermal conductivity of the smoking material under standard atmospheric pressure and room temperature is measured by a thermal constant analyzer, which is recorded as the thermal conductivity of the smoking material in the smoking section λ s .

[0066] Furthermore, the above test method can further limit the maximum thermal conductivity area thermal resistance to meet Furthermore, the thermal conductivity λ of the gap in the smoke section a When it is 0.026W / m·K, it satisfies

[0067] In addition, it can also be limited to 0.2<ε<0.6, δ is 0.0025m~0.0028m, λ s The temperature of the aerosol generating product is 0.07 to 0.32 W / m·K, which further increases the parameter requirements for the aerosol generating product, thereby optimizing the heating efficiency and aerosol release effect of the aerosol generating product.

[0068] This embodiment also proposes a method for preparing an aerosol-generating product by using the above-mentioned method for testing whether an aerosol-generating product is qualified, comprising the following steps:

[0069] Prepare a smoking segment that meets the conditions: prepare a smoking material that can generate aerosol by electric heating, assemble the smoking material in the smoking segment, the electric heating aerosol generating device includes a heating element, the heating element can be inserted into the smoking segment, and detect the maximum thermal conductivity area thermal resistance of the smoking segment Adjust the smoke section so that the maximum thermal conductivity area thermal resistance of the smoke section satisfy: The unit is m 2 K / W, where

[0070] δ: the maximum radial heating distance of the smoking section, in meters, expressed as the distance between the surface of the heating element and the smoking material at the farthest point in the normal direction of the surface;

[0071] λ e : Effective thermal conductivity of the smoke section, in W / m·K, and satisfies: λ e =ελ a +(1-ε)λ s ,in,

[0072] ε: void ratio of the smoking section, which is the ratio of the void volume of the smoking section to the total volume of the smoking section;

[0073] λ a : Thermal conductivity of the gap in the smoke section, in W / m·K;

[0074] λ s : Thermal conductivity of the smoke-generating material in the smoke-generating section, in W / m·K;

[0075] The thermal conductivity of the smoking material under standard atmospheric pressure and room temperature is tested using a thermal constant analyzer and recorded as the thermal conductivity of the smoking material in the smoking section λ s , test the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature, recorded as the thermal conductivity of the air gap of the smoking section λ a ; Finally, the smoking segment that meets the conditions is prepared into an aerosol generating product.

[0076] When the prepared smoking segment is inspected using the above-mentioned inspection method for aerosol generating products and does not meet the required range, it can be judged that the heating efficiency and aerosol release effect of the smoking segment are poor, and it is necessary to adjust the preparation process or the performance parameters of the smoking segment itself again, such as the porosity, or the radial size of the smoking segment, the thermal conductivity of the smoking material (the thermal conductivity can be improved by adjusting the material, density and other factors of the smoking material), etc., so that it meets the required range of the maximum thermal conductivity area thermal resistance. After adjustment, the smoking segment judged to be qualified will eventually complete the preparation of the aerosol generating product. Experiments have found that when the maximum thermal conductivity area thermal resistance of the aerosol generating product is obtained When the aerosol generating product is within the required range, it is found that the radial temperature difference is small when it is heated, and the utilization rate of the smoke-generating material, the aerosol release effect and the smoking experience are better. Aerosol generating products that are not within the required range are prone to the problem that the smoke-generating material inside near the heat source has been carbonized by high temperature while the radially outer temperature is still relatively low when heated, or the smoke-generating material utilization or aerosol release effect is poor.

[0077] Furthermore, the thermal conductivity of the smoke section gap λ a The smoke-generating section is prepared to meet the following requirements: Furthermore, the smoking section is prepared to satisfy:

[0078] The porosity of the smoking section ε can be obtained by the following method: the mass of the whole smoking material obtained at standard atmospheric pressure and room temperature is recorded as m s The volume of the whole smoking material is obtained under standard atmospheric pressure and room temperature, which is recorded as Vs ; The mass of the smoke section is obtained under standard atmospheric pressure and room temperature, recorded as m; the volume of the smoke section is obtained under standard atmospheric pressure and room temperature, recorded as V; the porosity ε of the smoke section satisfies:

[0079] Furthermore, the porosity ε of the smoke-generating section is adjusted to 0.2<ε<0.6. The radial maximum heating distance δ of the smoke-generating section is adjusted to 0.002-0.003 m, preferably 0.0025-0.0028 m.

[0080] The aerosol generating products obtained by the preparation methods in the above embodiments are particularly suitable for central heating, and the applicable aerosol generating device has a central heating element. The central heating element is inserted from the center of the aerosol generating product, and the central heating element is located at the center of the smoking section and extends along the axial direction of the smoking section. The central heating element can be, for example, a heating needle, a heating sheet, or a heating rod.

[0081] The following will use the preparation method of the above embodiment to prepare an aerosol generating product, wherein the reconstituted tobacco leaf sheet used as the smoking material can be prepared by the existing papermaking method or rolling method, and the aerosol generating product is heated and tested. The details are as follows:

[0082] Example:

[0083] Smoking material 1: Reconstituted tobacco leaf sheets prepared by papermaking process: extract the tobacco material to obtain extract, concentrate the extract, and mix it with the aerosol forming agent; the residue after the tobacco material extraction is made into paper with pulp fiber to form a paper base; the concentrate containing the aerosol generating agent is coated on the paper base, and the reconstituted tobacco leaf product is obtained after drying. The mass proportion of the aerosol generating agent in the finished material is about 20%, and the water proportion is about 7%. The thermal conductivity coefficient is measured by the thermal constant analyzer Hot Disk TPS2500S at standard atmospheric pressure and room temperature is 0.07W / m·K.

[0084] Smoking material 2: Reconstituted tobacco leaf flakes prepared by roller pressing process: The tobacco leaf is crushed into particles of about 300 mesh, mixed with aerosol generator, adhesive and water, rolled into a sheet with a thickness of 0.1-0.2 mm, and then dried at a temperature of about 100°C. The mass proportion of aerosol generator in the finished material is about 20%, and the mass proportion of water is about 5%. The thermal conductivity coefficient measured by the thermal constant analyzer Hot Disk TPS 2500S at standard atmospheric pressure and room temperature is 0.32W / m·K.

[0085] Smoking material 3: Smoking material 1 and smoking material 2 are uniformly blended at a mass ratio of 13% and 87%, respectively. The equivalent thermal conductivity thereof is measured by a thermal constant analyzer Hot Disk TPS 2500S at standard atmospheric pressure and room temperature to be 0.29 W / m·K.

[0086] Smoking material 4: Smoking material 1 and smoking material 2 are uniformly blended at a mass ratio of 30% and 70%, respectively. The equivalent thermal conductivity thereof is measured by a thermal constant analyzer Hot Disk TPS 2500S at standard atmospheric pressure and room temperature to be 0.25 W / m·K.

[0087] The smoking materials 1 to 4 are weighed according to the temperature of the smoking material farthest from the surface of the heating element along the normal direction of the heating element surface. The porosity shown is uniformly rolled into the corresponding packaging material to form an aerosol generating product. A needle-shaped heating element with a length of 12.5 mm and a radius of 0.001 m is inserted into the smoking section of the aerosol generating product that does not conform to and conforms to the present invention, respectively, and the axis of the heating element is kept coincident with the axis of the smoking section. The maximum radial heating distance of each product is 0.0025 m or 0.0028 m. The smoking section of each product is heated for 15 seconds under the same heating conditions. The temperature change law of the heating body is a linear increase from room temperature to about 410°C in the first 7 seconds, and maintained at about 410°C in the next 8 seconds. The temperature of the smoking material at the maximum radial heating point in the axial middle of the smoking section was measured using a J-type thermocouple. It was found that the temperature of the smoking material at the maximum radial heating point of the product in accordance with the present invention was significantly higher, and the temperature difference between the smoking material and the heat source at the corresponding maximum radial heating point was significantly smaller, indicating that heat can be more effectively transferred to the smoking material in the radial outer layer of the aerosol generating product. Furthermore, the aerosol generating product that meets the thermal resistance and porosity parameter values ​​of the maximum thermal conductivity area of ​​the smoking section of the present invention can achieve optimal heat transfer.

[0088] The radial maximum heated temperature refers to the temperature of the smoking material farthest from the surface of the heating element along the normal direction of the heating element surface.

[0089] In the following examples, the radial maximum heated point temperature of product 1 and product 2 is low, and the heat transfer effect and heating efficiency are poor. Specifically, the thermal conductivity of the material, or the thermal resistance of the thermal conductivity, affects the steady-state thermal conductivity, and the porosity affects the heat diffusion capacity. The maximum thermal conductivity area thermal resistance and porosity of products 3-6 meet the requirements, ensuring the thermal conductivity and heat diffusion capacity, so the radial maximum heated point temperature is high and the heat transfer effect is good.

[0090] Table 1 Parameters and performance of aerosol generating products

[0091]

[0092] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. An aerosol generating product for use with an electrically heated aerosol generating device, characterized in that: The device comprises a smoking section, wherein the smoking material is contained therein, the electrically heated aerosol generating device comprises a heating element, the heating element can be inserted into the smoking section, the heating element is a heating needle, a heating sheet or a heating rod, and the maximum thermal conductivity area thermal resistance of the smoking section is satisfy: The unit is m 2 K / W, in, δ: the maximum radial heating distance of the smoking section, in meters, expressed as the distance between the surface of the heating element and the smoking material at the farthest point in the normal direction of the surface; λ e : Effective thermal conductivity of the smoke section, in W / m·K, and satisfies: λ e =ελ a +(1-ε)λ s ,in, ε: void ratio of the smoking section, which is the ratio of the void volume of the smoking section to the total volume of the smoking section; λ a : Thermal conductivity of the gap in the smoke section, in W / m·K; λ s : Thermal conductivity of the smoke-generating material in the smoke-generating section, in W / m·K; The porosity ε of the smoke-generating section satisfies 0.2<ε<0.6, and the radial maximum heating distance δ of the smoke-generating section is 0.0025-0.0028 m.

2. The aerosol-generating article according to claim 1, wherein Thermal conductivity λ of the smoke-generating material in the smoke-generating section s The thermal conductivity of the smoke-generating material is tested by a thermal constant analyzer at standard atmospheric pressure and room temperature. The thermal conductivity of the gap in the smoke-generating section is a It is the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature.

3. The aerosol-generating article of claim 1, wherein: Thermal conductivity of the gap in the smoke section λ a is 0.026W / m·K, and the smoke section satisfies:

4. An aerosol-generating article according to claim 3, characterized in that The smoking section satisfies 5. The aerosol-generating article of claim 1, wherein: The porosity ε of the smoking section satisfies: Among them, m s V is the mass of the whole piece of smoking material obtained at standard atmospheric pressure and room temperature; s is the volume of the entire smoking material at standard atmospheric pressure and room temperature; m is the mass of the smoking section at standard atmospheric pressure and room temperature; V is the volume of the smoking section at standard atmospheric pressure and room temperature.

6. An aerosol-generating article according to any one of claims 1 to 5, characterized in that Thermal conductivity λ of the smoke-generating material in the smoke-generating section s It is 0.07~0.32W / m·K.

7. An aerosol-generating article according to any one of claims 1 to 5, characterized in that The heating element is a central heating element, and the smoking segment is adapted to be centrally heated.

8. An aerosol generating system, characterized in that: The invention comprises an aerosol generating product as claimed in any one of claims 1 to 7, and an electrically heated aerosol generating device suitable for heating the aerosol generating product.

9. A method for preparing an aerosol generating product for use with an electrically heated aerosol generating device, characterized in that: The following steps are involved: Prepare a smoking segment that meets the conditions: prepare a smoking material that can generate aerosol by electric heating, assemble the smoking material in the smoking segment, the electric heating aerosol generating device includes a heating element, the heating element can be inserted into the smoking segment, and detect the thermal resistance of the maximum thermal conductivity area of ​​the smoking segment The smoke section is adjusted so that the maximum thermal resistance of the heat conduction area of ​​the smoke section satisfy: The unit is m 2 K / W, in, δ: the maximum radial heating distance of the smoking section, in meters, expressed as the distance between the surface of the heating element and the smoking material at the farthest point in the normal direction of the surface; λ e : Effective thermal conductivity of the smoke section, in W / m·K, and satisfies: λ e =ελ a +(1-ε)λ s ,in, ε: void ratio of the smoking section, which is the ratio of the void volume of the smoking section to the total volume of the smoking section; λ a : Thermal conductivity of the gap in the smoke section, in W / m·K; λ s : Thermal conductivity of the smoke-generating material in the smoke-generating section, in W / m·K; The smoking segment that meets the conditions is prepared into the aerosol generating product.

10. The method for preparing an aerosol-generating article according to claim 9, wherein: The thermal conductivity of the smoking material under standard atmospheric pressure and room temperature is tested using a thermal constant analyzer, and is recorded as the thermal conductivity λ of the smoking material in the smoking section. s , test the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature, recorded as the thermal conductivity of the air gap of the smoking section λ a .

11. The method for preparing an aerosol-generating article according to claim 9, wherein: Thermal conductivity of the gap in the smoke section λ a The smoke-generating section is prepared to meet the following requirements:

12. The method for preparing an aerosol-generating article according to claim 11, wherein: The smoking section is prepared to satisfy:

13. The method for preparing an aerosol-generating article according to claim 9, wherein: The mass of the whole piece of smoking material obtained at standard atmospheric pressure and room temperature is recorded as m s The volume of the whole smoking material is obtained under standard atmospheric pressure and room temperature, which is recorded as V s ; The mass of the smoking section is obtained under standard atmospheric pressure and room temperature, which is recorded as m; the volume of the smoking section is obtained under standard atmospheric pressure and room temperature, which is recorded as V; the porosity ε of the smoking section is obtained by the following method:

14. A method for preparing an aerosol-generating article according to any one of claims 9 to 13, characterized in that: The void ratio ε of the smoking section is adjusted to 0.2<ε<0.

6.

15. A method for preparing an aerosol-generating article according to any one of claims 9 to 13, characterized in that: The maximum radial heating distance δ of the smoke-generating section is adjusted to 0.0025-0.0028 m.

16. A method for preparing an aerosol-generating article according to any one of claims 9 to 13, characterized in that: The thermal conductivity of the smoke-generating material in the smoke-generating section is s Adjust to 0.07~0.32W / m·K.

17. A method for preparing an aerosol-generating article according to any one of claims 9 to 13, characterized in that: The heating element is a central heating element, and the smoking segment is prepared to be suitable for being centrally heated.

18. A method for testing an aerosol-generating product, characterized in that: The aerosol generating article is used for use with an electrically heated aerosol generating device, the aerosol generating article comprises a smoking segment containing a smoking material, the electrically heated aerosol generating device comprises a heating element, the heating element can be inserted into the smoking segment, and the testing step comprises: The porosity of the smoking section is obtained, which is recorded as ε. The porosity of the smoking section is the ratio of the volume of the voids in the smoking section to the total volume of the smoking section. The thermal conductivity of the voids in the smoking section is obtained as λ. a , in units of W / m·K; obtain the thermal conductivity λ of the smoking material in the smoking section s , the unit is W / m·K; the effective thermal conductivity of the smoke section is calculated by the formula, recorded as λ e , the unit is W / m·K, where the formula is λ e =ελ a +(1-ε)λ s ; Obtain the distance between the surface of the heating element and the farthest smoking material in the normal direction of the surface, which is recorded as the maximum radial heating distance δ of the smoking section, in m; divide the maximum radial heating distance δ of the smoking section by the effective thermal conductivity λ of the smoking section e , get the maximum thermal resistance of the thermal conductivity area, unit is m 2 K / W; Check the thermal resistance of the maximum thermal conductivity area Whether it meets: If the maximum thermal conductivity area thermal resistance satisfy: The aerosol generating product containing the smoking segment or the smoking segment is judged to be qualified, otherwise it is unqualified.

19. The inspection method according to claim 18, characterized in that: Get the thermal conductivity λ of the gap in the smoke section a It includes testing the thermal conductivity of the air gap between the smoking materials under standard atmospheric pressure and room temperature, which is recorded as the thermal conductivity of the air gap of the smoking section λ a , obtain the thermal conductivity λ of the smoking material in the smoking section s The thermal conductivity of the smoking material under standard atmospheric pressure and room temperature is measured by a thermal constant analyzer, which is recorded as the thermal conductivity of the smoking material in the smoking section λ s .

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