A cigarette with improved dynamic resistance consistency
By adjusting the air intake and setting ventilation holes in the cigarette design, the problem of large fluctuations in cigarette draw resistance was solved, and the consistency of draw resistance and the comfort of smoking were improved.
Patent Information
- Application Number
- CN202610658514.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-13
- Publication Date
- 2026-06-12
AI Technical Summary
During the smoking process, the resistance of cigarettes fluctuates greatly, especially for medium and slim cigarettes, which affects the sensory experience of smoking.
By limiting the extension length of the tipping paper, the parameter specifications of the first vent, and the air permeability of the cigarette paper in the design of the filter section and the core section, the air intake during the combustion process is controlled, and a second vent is set in the axial middle area of the filter section to achieve precise control of the suction resistance in conjunction with the first vent.
It significantly improves the consistency of dynamic draw resistance of cigarettes, optimizes the taste of smoke, reduces discomfort during smoking, and enhances the user's smoking experience.
Smart Images
Figure CN122181748A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of cigarette manufacturing technology, and more specifically, to a cigarette with improved dynamic draw resistance consistency. Background Technology
[0002] In the process of cigarette development, tobacco companies usually use the draw resistance of an unlit cigarette as one of the standards for measuring sensory experience. However, in actual smoking, the draw resistance after the cigarette is lit is significantly different from that when it is unlit. Furthermore, the draw resistance changes significantly as the core burns throughout the smoking process, resulting in large fluctuations in draw resistance.
[0003] Especially for medium and slim cigarettes, the fluctuation in draw resistance is more pronounced, which is one of the important factors affecting the sensory experience during smoking. Therefore, it is necessary to improve the structure of cigarettes to enhance the consistency of draw resistance during smoking. Summary of the Invention
[0004] In view of this, the purpose of this application is to provide a cigarette that improves the consistency of dynamic draw resistance, which can improve the problem that the combustion cone of traditional cigarettes has a higher resistance to airflow than the filter, resulting in a greater draw resistance of the entire cigarette in the later stages of smoking.
[0005] To achieve the above technical objectives, the technical solution adopted in this application is as follows:
[0006] This application provides a cigarette with improved dynamic draw resistance consistency, the cigarette comprising a filter section and a filler section;
[0007] The filter section is covered with tipping paper, which extends towards one end of the cigarette core section and beyond the junction of the filter section and the cigarette core section by a predetermined distance. A first vent hole is provided on the axial section of the tipping paper that extends beyond the junction and covers the cigarette core section.
[0008] The core segment is covered with cigarette paper, and the air permeability of the cigarette paper is less than or equal to 30 CU; where CU is a unit of air permeability, defined as the number of milliliters of air passing through per square centimeter per minute, i.e., 1 CU = 1 ml / cm²·min.
[0009] In this application, by limiting the extension length of the tipping paper, the parameter specifications of the first vent, and the air permeability of the cigarette paper, the air intake during the cigarette combustion process is controlled, avoiding large fluctuations in the draw resistance, significantly improving the consistency of the dynamic draw resistance of the cigarette, while optimizing the smoke taste, reducing discomfort during the smoking process, and improving the user's smoking experience.
[0010] Furthermore, the air permeability of the cigarette paper is 10CU to 30CU. Limiting the air permeability of the cigarette paper to the above range can further optimize the matching with the air permeability of the tipping paper, taking into account both the cigarette burning speed and the stability of the draw resistance. This avoids the situation where the draw resistance is too low and the smoke is too weak due to excessively high air permeability of the cigarette paper, or the draw resistance is too high and the draw is difficult due to excessively low air permeability, thereby further improving the consistency of dynamic draw resistance and the comfort of drawing.
[0011] Furthermore, the air permeability of the tipping paper is zero; the air permeability of the cigarette paper is 10 CU. By limiting the air permeability of the cigarette paper to this specific value of 10 CU, the amount of air intake during the cigarette combustion process can be precisely controlled.
[0012] Furthermore, a second vent is provided in the axial central region of the tipping paper-covered filter tip section. This second vent, in conjunction with the first vent, allows for precise control of suction resistance.
[0013] Furthermore, the diameter of the second vent is larger than that of the first vent. Both the first and second vents are located circumferentially around the cigarette.
[0014] Furthermore, the length of the filter segment is 24mm to 33mm, and the ratio of the length of the filter segment to the length of the cigarette core segment is 0.3 to 0.5. By limiting the length of the filter segment and its ratio to the length of the cigarette core segment, and coordinating this with the air permeability and pore parameters of the cigarette paper, precise matching of the overall draw resistance of the cigarette can be achieved. This avoids abnormal draw resistance caused by the filter segment being too long or too short, ensuring that the dynamic draw resistance of the cigarette remains stable throughout the entire smoking process.
[0015] The invention employing the above technical solution has the following advantages:
[0016] In the technical solution provided in this application, by limiting the extension length of the tipping paper, the parameter specifications of the first air vent, and the air permeability of the cigarette paper, the air intake during the cigarette combustion process is controlled, so as to avoid large fluctuations in the draw resistance and significantly improve the consistency of the dynamic draw resistance of the cigarette.
[0017] A second vent is provided in the axial middle region of the filter tip section, which can work in conjunction with the first vent to achieve precise control of suction resistance. Attached Figure Description
[0018] This application can be further illustrated by the non-limiting embodiments given in the accompanying drawings. It should be understood that the following drawings only illustrate some embodiments of this application and should not be considered as limiting the scope. For those skilled in the art, other related drawings can be obtained from these drawings without any inventive effort.
[0019] Figure 1 This is a puff-by-puff curve of the change in suction resistance during the cigarette smoking process in the embodiments of this application;
[0020] Figure 2 This is a graph showing the changes in flow rate and pressure within the cigarette as a function of axial position (cigarette length is 97 mm) in an embodiment of this application.
[0021] Figure 3 This is a graph showing the changes in flow rate and pressure within the cigarette as a function of axial position (cigarette length is 46.8 mm) in an embodiment of this application.
[0022] Figure 4 This is a schematic diagram of a simulation structure in which a vent is added at the junction of the filter section and the core section in an embodiment of this application;
[0023] Figure 5 This is a schematic diagram of the physical model of the initial smoking of a conventional cigarette in the embodiments of this application;
[0024] Figure 6 This is a schematic diagram of the physical model of the later stage of conventional cigarette smoking in the embodiments of this application;
[0025] Figure 7 This is a diagram showing the experimental results of the improved cigarette puff resistance measurement in this embodiment of the application.
[0026] In the attached diagram: filter tip section 10 wrapped in tipping paper, cigarette core section 20 wrapped in tipping paper, tipping paper 21, first vent 22, cigarette core section 30 wrapped in cigarette paper, cigarette paper 31, and combustion cone 40. Detailed Implementation
[0027] The present application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that similar or identical parts are referred to by the same reference numerals in the drawings or description. Implementations not shown or described in the drawings are forms known to those skilled in the art. In the description of this application, terms such as "first" and "second" are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0028] Please refer to Figures 1 to 7 This application provides a cigarette with improved dynamic draw resistance consistency, the cigarette including a filter section 10 and a core section 30;
[0029] The filter section 10 is covered with tipping paper 21. The tipping paper 21 extends toward the end of the core section 30 and exceeds the predetermined distance at the junction of the filter section 10 and the core section 30. A first vent hole 22 is opened on the axial section of the tipping paper 21 that extends beyond the junction and covers the core section 30.
[0030] The core segment 30 is covered with cigarette paper 31, and the air permeability of the cigarette paper 31 is less than or equal to 30CU; where CU is a unit of air permeability, defined as the number of milliliters of air passing through per square centimeter per minute, i.e., 1CU=1ml / cm²·min.
[0031] In this embodiment, by limiting the extension length of the tipping paper 21, the parameter specifications of the first air vent 22, and the air permeability of the cigarette paper 31, the air intake during the cigarette combustion process is controlled, avoiding large fluctuations in the draw resistance, significantly improving the consistency of the dynamic draw resistance of the cigarette, while optimizing the smoke taste, reducing discomfort during the smoking process, and improving the user's smoking experience.
[0032] In fact, the draw resistance of a lit cigarette differs significantly from that of an unlit cigarette during the smoking process, and the draw resistance changes significantly throughout the entire smoking process as the core burns. For example... Figure 1 As shown, the horizontal axis represents time in seconds, increasing sequentially from left to right; the vertical axis represents the negative pressure at the end of the filter, i.e., the draw resistance; the graph shows the change in draw resistance for each puff from left to right. It can be seen from the graph that the draw resistance is higher during the first puff, gradually decreasing during the second and third puffs, increasing again from the fourth puff, and gradually rising in subsequent puffs; the draw resistance fluctuates up to 500 Pa throughout the entire smoking process; and the consistency of draw resistance during cigarette smoking is poor.
[0033] like Figure 5 As shown, for a regular cigarette, the filter tip is on the far left, with its coordinate x=0, and the total length of the cigarette is L. There are three paths for air to enter the cigarette: the vent on the filter section 10 (such as the second vent), the cigarette paper 31, and the combustion cone 40. For a regular cigarette with a length of 97mm, when drawn at 17.5ml / s, the flow rate and pressure distribution within the cigarette are calculated using a theoretical drawing model as follows: Figure 2 As shown. At this point, the air permeability of the cigarette paper is CU=60, the flow rate entering through the cigarette paper is 4.06 ml / s, accounting for 23.19%; the flow rate entering through the filter orifice (i.e., the second air perforation hole) is 9.06 ml / s, accounting for 51.76%. As the smoking process continues, the combustion cone 40 slowly moves towards the filter section 10 until the cigarette paper 31 is completely burned, as... Figure 6 As shown; the changes in flow rate and pressure within the cigarette with axial position are as follows: Figure 3As shown, the cigarette length is 46.8 mm at this point. The flow rate entering through the cigarette paper 31 is 0.12 ml / s, accounting for 0.68%; the flow rate entering through the filter orifice is 9.61 ml / s, accounting for 54.89%. Therefore, the flow rate change of the filter orifice (i.e., the second vent) during the entire smoking process is 3.13%, while the change in air permeability of the cigarette paper 31 is 22.51%. The air permeability of the cigarette paper 31 gradually decreases until it reaches 0. The reduced airflow from the cigarette paper 31 is distributed to the filter orifice (i.e., the second vent) and the combustion cone 40, and is mainly distributed to the combustion cone 40. The combustion cone 40 has a higher resistance to airflow than the filter, which is the fundamental reason for the increased draw resistance of the entire cigarette in the later stages of smoking. To improve the consistency of dynamic draw resistance during the cigarette smoking process, the cigarette of this embodiment is provided, such as... Figure 4 As shown. Experimental verification shows that... Figure 7 As shown, the improved cigarettes exhibit significantly reduced dynamic draw resistance during the smoking process, and the fluctuation of draw resistance is also smaller throughout the entire smoking process, which can effectively improve the comfort of the taste.
[0034] The following is a detailed description of a cigarette that improves dynamic draw resistance consistency:
[0035] In this embodiment, the cigarette includes a filter section 10 and a filler section 30, wherein the filter section 10 is 28mm long and the filler section 30 is 69mm long.
[0036] The filter section 10 is covered with tipping paper 21, which is made of cigarette tipping paper and has zero air permeability. The tipping paper 21 extends 3mm beyond the junction of the filter section 10 and the cigarette core section 30 (i.e., the cigarette core section 20 wrapped by the tipping paper). This extension length can ensure the stability of the tipping paper covering the junction and provide a reasonable opening position for the first vent 22, avoiding uneven air intake caused by the vent being too close to the junction.
[0037] The tipping paper extends beyond the joint and covers the axial section of the tobacco core with a first vent hole. The diameter of the first vent hole is 0.5 mm and there are 9 holes. They are evenly distributed along the circumference of the tipping paper (the central angle between two adjacent vent holes is 40°). This parameter setting can ensure uniform air intake and avoid fluctuations in suction resistance caused by excessive or insufficient local air intake.
[0038] The core section 30 is covered with cigarette paper 31, which has an air permeability of 16.7 CU to ensure stable air permeability during combustion and prevent damage.
[0039] For example, the dimensional parameters of a typical cigarette are shown in Table 1 below.
[0040] Table 1 shows the size parameters of commonly available cigarettes on the market.
[0041]
[0042] If the dimensions of the fixed cigarette remain unchanged, then,
[0043] Firstly, the air pore parameters are kept constant, while the number of values for the air permeability parameter is gradually increased.
[0044] Secondly, the air permeability parameter is kept constant, while the number of values for the gradient expansion air pore parameter is increased.
[0045] Finally, two sets of parameter combinations were obtained.
[0046] In fact, the core section 30 is covered with cigarette paper 31, which has an air permeability of 30 CU; the tipping paper 21 is not air permeable.
[0047] In some implementation scenarios of this embodiment, the air permeability of the cigarette paper 31 is 25CU; the tipping paper 21 extends beyond the joint and covers the axial section of the cigarette core section and has a first air permeable hole 22. The diameter of the first air permeable hole 22 is 0.5mm and there are 7 holes, which are evenly arranged along the circumference of the tipping paper 21.
[0048] In other implementations of this embodiment, the air permeability of cigarette paper 31 is 10 CU.
[0049] In this embodiment, a second vent is provided in the axial middle region of the filter section 10 covered by the tipping paper 21 (this region is between 1 / 3 and 2 / 3 of the length of the filter section, that is, the region 9.3 mm to 18.7 mm away from the end of the filter section away from the tobacco core section).
[0050] The second vent has a diameter of 0.8 mm, which is larger than the first vent's 0.5 mm. There are five vents, evenly distributed around the circumference of the tipping paper 21. Testing showed that the draw resistance consistency was further improved, and the smoke temperature decreased during inhalation, significantly reducing the burning sensation and significantly optimizing inhalation comfort. This demonstrates that the second vent works in conjunction with the first vent 22 to further enhance dynamic draw resistance consistency and the inhalation experience.
[0051] In some other implementation scenarios of this embodiment, based on the previous embodiment, the diameter of the second vent 22 is adjusted to 1.2 mm, the number of vents is 2, and they are evenly arranged around the tipping paper 21. The diameter of the first vent 22 is 0.6 mm, the number of vents is 6, and the other parameters are the same as in the previous embodiment.
[0052] The cigarette in this embodiment, after testing, showed a dynamic draw resistance fluctuation of 4.8%, excellent draw resistance consistency, and uniform smoke taste with no smoke dilution. This proves that the diameter and number of the second air vent are matched with the first air vent 22, which can achieve two-stage air intake control, taking into account both draw resistance consistency and taste.
[0053] In summary, this application, by limiting the extension length of the tipping paper 21, the parameters of the first air pore 22, and the air permeability of the cigarette paper 31, combined with optional parameters of the second air pore and the length ratio of the filter section 10 to the core section 30, can effectively control the fluctuation range of the dynamic draw resistance of cigarettes, achieve consistency in dynamic draw resistance, and optimize the smoking experience. Tests of various embodiments prove that the combination of technical features of this application is the key to achieving the purpose of the invention, and the technical solution is simple, easy to mass-produce industrially, and has good practicality and promotional value.
[0054] This embodiment uses a cigarette with a length L=97mm as the test object. Based on the cigarette provided by this invention, combined with specific experimental data and simulation analysis, the design parameters of the cigarette are selected. The specific implementation is as follows:
[0055] First, determine the design parameters and smoking settings for the experimental cigarette, including:
[0056] The design parameters include: cigarette size parameters (selecting a conventional initial cigarette length L=97mm), air perforation parameters on the filter section (the number of air perforations can be adjusted in a gradient; initially, several small holes are added at the junction of the filter and the core section to form increased air perforations (the comparative example does not have increased air perforations)), and air permeability parameters of the cigarette paper in the core section (the gradient value range is CU=10~60, covering the range from low air permeability to conventional air permeability).
[0057] The aspiration settings were determined with reference to relevant national standards. Specifically, the aspiration capacity was 17.5 ml / s, and the aspiration duration, aspiration frequency, and ambient temperature and humidity remained unchanged from the standard values.
[0058] Using the controlled variable method, while keeping the cigarette size parameter (97mm) constant, the number of filter pores and the air permeability of cigarette paper were increased in a gradient to construct an experimental condition library. Specifically, the cigarette paper air permeability gradient was set to six groups (CU=10, 20, 30, 40, 50, 60); the number of filter pores was increased by two pores per group, with five different parameters set, ultimately forming 30 parameter combinations, which were stored in the experimental condition library.
[0059] By constructing a theoretical model of inhalation, the dynamic process of inhalation is simulated. The pre-constructed theoretical model of inhalation is based on the fluid dynamics experiments and numerical simulations of the cigarette inhalation process. It can accurately simulate the dynamic evolution of the combustion cone along the cigarette axis during the cigarette inhalation process, and at the same time record the air flow data of the filter section, the core section, the combustion cone, and the pressure distribution inside the cigarette in real time.
[0060] In fact, the theoretical model of smoking can be constructed based on the smoking process simulation of Saidi & Hajaligol (2004) (Chinese translation: Experimental and Numerical Analysis of Fluid Dynamics of Cigarette Smoking); or, open source databases can be directly used for API calls, such as the GitCode cigarette combustion simulation project, to modify the initial and smoking parameters and quickly obtain evolution results for preliminary verification.
[0061] The design parameters were retrieved one by one from the experimental condition library. Each set of design parameters, together with the above-mentioned suction setting parameters, was input into the suction theoretical model. The simulation program was started to simulate the complete suction process of the test cigarette from ignition to complete combustion. The airflow data of two key nodes were recorded: the initial suction stage (cigarette length is 97mm) and the later suction stage (cigarette length is 46.8mm, at which point the cigarette paper has been basically burned off). At the same time, the data on the change of suction resistance for each puff during the entire suction process were recorded, and the change curve of suction resistance was plotted.
[0062] Based on the relationship between airflow data and fluid pressure drop recorded by the suction theory model, the draw resistance variation curves corresponding to each set of design parameters and their variation with the axial position of the combustion cone in the cigarette were calculated. The draw resistance is measured by the negative pressure value at the end of the filter tip, with the horizontal axis representing the axial position of the combustion cone and the vertical axis representing the draw resistance value.
[0063] After all 30 sets of parameter combinations in the experimental condition library have been simulated, all suction resistance change curves are read. Taking the filter end as the origin (x=0) as the initial point, all suction resistance change curves are aligned. Using the preset extraction node as the selection point, the fluctuation amplitude of each set of curves is compared. At the same time, the influence priority of different parameters on suction resistance fluctuation is analyzed by combining the control variable method.
[0064] Compare the simulation results of two typical parameter combinations:
[0065] Combination 1: Cigarette paper permeability CU=60 (normal permeability), filter tip vent number is the initial setting value. Simulation results show that when the cigarette length is 97mm, the flow rate through the cigarette paper is 4.06 ml / s, accounting for 23.19%; the flow rate through the filter tip vents (i.e., vents) is 9.06 ml / s, accounting for 51.76%. When the cigarette length is 46.8mm, the flow rate through the cigarette paper is 0.12 ml / s, accounting for 0.68%; the flow rate through the filter tip vents is 9.61 ml / s, accounting for 54.89%. During the entire smoking process, the change in cigarette paper permeability is 22.51%, the change in filter tip vent flow rate is 3.13%, and the draw resistance fluctuation is as high as about 500Pa, with a large fluctuation range.
[0066] Combination 2: Cigarette paper air permeability CU=10 (low air permeability), the number of filter vents is increased, keeping the sum of the initial vents and the cigarette paper's ventilation volume at around 70%. Simulation results show that when the cigarette length is 97mm, the flow rate of the filter vents (i.e., ventilation holes) is 11.35 ml / s, accounting for 64.86%; the cigarette paper's air permeability is 0.81 ml / s, accounting for 4.63%. When the cigarette length is 46.80mm, the flow rate of the filter vents is 10.89 ml / s, accounting for 62.21%; the cigarette paper's air permeability is 0.02 ml / s, accounting for 0.09%. The suction resistance fluctuation during the entire smoking process is only 100Pa, and the fluctuation range of suction resistance is significantly reduced.
[0067] By comparing the draw resistance fluctuations of all 30 parameter combinations and combining the control variable method, it was finally determined that when the cigarette paper air permeability is set within the range of CU=10~30, and a suitable number of air holes is added to the filter tip, the change in draw resistance before and after smoking is minimized, and the draw resistance fluctuation is lowest. The parameter combination within this range is the optimal design parameter for the experimental cigarette. Specifically, the optimal design parameter combination is a cigarette paper air permeability CU=10, with additional air holes added at the junction of the filter tip and the cigarette core (e.g., ...). Figure 4 As shown in the figure, the suction resistance fluctuation is minimal at this point.
[0068] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. A cigarette with improved dynamic draw resistance consistency, characterized in that, The cigarette includes a filter section and a filler section; The filter section is covered with tipping paper, which extends towards one end of the cigarette core section and beyond the junction of the filter section and the cigarette core section by a predetermined distance. A first vent hole is provided on the axial section of the tipping paper that extends beyond the junction and covers the cigarette core section. The core segment is covered with cigarette paper, and the air permeability of the cigarette paper is less than or equal to 30 CU.
2. The cigarette according to claim 1, characterized in that, The air permeability of the cigarette paper is 10 CU to 30 CU.
3. The cigarette according to claim 2, characterized in that, The air permeability of the cigarette paper is 10 CU.
4. The cigarette according to any one of claims 1-3, characterized in that, A second vent is provided in the axial middle region of the tipping paper-wrapped filter tip section.
5. The cigarette according to claim 4, characterized in that, The diameter of the second vent is larger than that of the first vent.
6. The cigarette according to claim 4, characterized in that, Both the first and second ventilation holes are opened along the circumference of the cigarette.
7. The cigarette according to claim 1, characterized in that, The length of the filter section is 24mm to 33mm, and the ratio of the length of the filter section to the length of the cigarette core section is 0.3 to 0.
5.
8. The cigarette according to claim 1, characterized in that, The air permeability of the cork paper is zero.