A cigarette filter rod and application thereof

Abstract

This invention discloses a cigarette filter rod and its application. The cigarette filter rod is obtained by converging and rotating parallel polylactic acid strips along a central axis and then fixing them with an outer wrapping layer. The rotation angle of each individual polylactic acid strip along the filter rod axis is independently 1-89°, and at least one polylactic acid strip has at least one protrusion. This cigarette filter rod allows the smoke to pass through the filter rod, where the polylactic acid condenses and traps the smoke, and the protrusions adsorb water, tar, and other substances in the smoke, effectively reducing the tar content and temperature of the smoke.

Description

Technical Field

[0001] This invention belongs to the technical field of the tobacco industry, specifically relating to a cigarette filter rod and its application. Background Technology

[0002] Cigarette filters reduce tar primarily through mechanical interception, inertial compression, diffusion sedimentation, and adsorption. Existing filter materials mainly include cellulose acetate, paper, and polypropylene fibers (including non-woven fabrics), which present the following problems: firstly, cellulose acetate and polypropylene fibers are not easily degraded, causing environmental pollution; secondly, paper materials negatively impact the taste of cigarettes. Polylactic acid (PLA), as a safe and biodegradable material, is considered the most promising green "eco-material" and is therefore increasingly used in the cigarette industry.

[0003] CN116035259A discloses a method for preparing polylactic acid fiber hollow filter rods, relating to the field of hollow filter rod technology. The method includes the following steps: after the polylactic acid fiber bundles are loosened, they are fed into a forming cavity, and the polylactic acid fiber bundles are heated and cured by heated air to obtain polylactic acid fiber hollow filter rods. This invention uses hot air to heat and cure the polylactic acid fiber bundles to obtain polylactic acid fiber hollow filter rods, resulting in good forming effect, good regularity, and low pollution.

[0004] CN115506041A discloses a method for preparing a polylactic acid fiber filter rod with good temperature resistance, relating to the field of cigarette manufacturing technology. This invention is simple and convenient. By controlling the proportion and preparation of polylactic acid raw materials, a multi-layered core-sheath type polylactic acid fiber is obtained, improving the uniformity of its inner layer structure. The resulting polylactic acid fiber filter rod is stable to cut, and the crystallinity and temperature resistance gradually change from the inside to the outside of the fiber bundle, making the entire filter rod have better temperature resistance and improving the filtration performance of the polylactic acid fiber bundle.

[0005] Polylactic acid (PLA) fibers, used as cigarette filter materials, present several challenges in practical applications: PLA with good heat resistance cannot be bonded under the action of triacetin, resulting in insufficient adhesion and preventing the formation of filter rods; while PLA with poor heat resistance can be bonded under triacetin, the fibers tend to stick together, and the prepared filter rods shrink in environments above room temperature. Furthermore, the smooth surface of PLA fibers limits their effectiveness in adsorbing cigarette tar. Therefore, improving the rod-forming properties of PLA and enhancing its filtration efficiency for cigarette smoke is a pressing issue that needs to be addressed. Summary of the Invention

[0006] To address the shortcomings of existing technologies and practical needs, this invention provides a cigarette filter rod and its application. The cigarette filter rod can effectively reduce tar and temperature in cigarette smoke as it passes through its unique structure.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a cigarette filter rod, which is obtained by converging strips of polylactic acid together and rotating them along a central axis, and then fixing them with an outer wrapping layer. The rotation angle of each polylactic acid strip along the axis of the filter rod is independently 1-89° (e.g., 2°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80° or 85°, etc.), and at least one strip of polylactic acid has at least one protrusion.

[0008] The cigarette filter rod of the present invention, by rotating the polylactic acid strip, can create an obstruction effect on the smoke during the flow process, thereby effectively improving the condensation of moisture, the interception of tar and other harmful components in the smoke, and reducing the temperature of the smoke. At the same time, by setting protrusions in the strip-shaped polylactic acid, it can avoid the blockage of the smoke channel caused by close contact between adjacent polylactic acid strips, reduce the suction resistance, and make the user experience better.

[0009] Preferably, the rotation angle of a single polylactic acid bar along the axis of the filter rod is 10-30°, for example, it can be 11°, 13°, 15°, 17°, 19°, 20°, 21°, 23°, 25°, 27° or 29°.

[0010] Preferably, the strip-shaped polylactic acid is prepared by longitudinally and continuously cutting foamed polylactic acid sheets to obtain the strip-shaped polylactic acid.

[0011] In this invention, after the foamed polylactic acid is cut, the polylactic acid foam cells at the cut end rupture, forming pores. The cut polylactic acid strip has a large number of pores, which effectively increases the adsorption area and greatly improves the interception of tar and condensation of moisture in the flue gas, thereby reducing the harmful components and temperature of the flue gas.

[0012] Preferably, the spacing of the cuts is 0.5-3mm, for example, it can be 0.6mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm or 2.8mm, etc.

[0013] Preferably, the area of ​​the puncture is independently greater than 5% of the outer surface area of ​​the strip-shaped polylactic acid, for example, it can be 6%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45% or 50%, etc.

[0014] Preferably, the area of ​​the puncture is independently greater than 20% of the outer surface area of ​​the strip-shaped polylactic acid.

[0015] Preferably, the thickness of the foamed polylactic acid sheet is 0.2-2 mm, for example, it can be 0.3 mm, 0.5 mm, 0.7 mm, 1 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm or 1.9 mm.

[0016] Preferably, the thickness of the foamed polylactic acid sheet is 0.3-1.5 mm, for example, it can be 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm or 1.4 mm.

[0017] Preferably, the outer surface of the polylactic acid is coated with an adsorption coating.

[0018] Preferably, the thickness of the adsorption coating is 0.05-0.3 mm, for example, it can be 0.07 mm, 0.09 mm, 0.1 mm, 0.12 mm, 0.14 mm, 0.16 mm, 0.18 mm, 0.2 mm, 0.22 mm, 0.24 mm, 0.26 mm or 0.28 mm, etc.

[0019] Preferably, the adsorption coating comprises any one or a combination of at least two of licorice fluid extract, chicory extract, or black tea tincture.

[0020] Preferably, the adsorption coating is licorice fluid extract, chicory extract, and black tea tincture.

[0021] In this invention, the coating layer comprises licorice fluid extract, chicory extract, and black tea tincture. The licorice fluid extract enhances the sweetness of the smoke and reduces its irritation; the chicory extract harmonizes with the aroma of the smoke and moderates its spiciness; and the black tea tincture harmonizes with the aroma of the smoke, enhancing its natural flavor and improving the overall aroma and taste. The chemical components in the adsorption coating, such as inulin and other polysaccharides, chicoric acid and other organic acids, caffeine and other alkaloids, and catechins, contribute to the adsorption of moisture and tar from the smoke by the filter rod.

[0022] Preferably, the mass ratio of the licorice fluid extract, chicory extract, and black tea tincture is 1:(1-3):(1-3), for example, it can be 1:1:1, 1:1:2, 1:1:3, 1:2:1, 1:3:1, 1:1.5:1, 1:2.5:1, 1:1:1.5, 1:1:2.5, 1:2:1.5, 1:2:2.5, 1:3:1.5, 1:3:2.5, or 1:3:3, etc.

[0023] Preferably, the number of strip-shaped polylactic acid with protrusions is 10-100% of the total number of strip-shaped polylactic acid, for example, it can be 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90%, etc.

[0024] Preferably, the height of the protrusion is independently 10%-50% of the thickness of the strip polylactic acid, for example, it can be 15%, 20%, 25%, 30%, 35%, 40% or 45%.

[0025] Preferably, the interior of the protrusion contains granular material.

[0026] Preferably, the granular material comprises any one or a combination of at least two of sodium polyacrylate, perlite, diatomaceous earth, kaolin, or montmorillonite.

[0027] Preferably, the granules are a mixture of sodium polyacrylate and kaolin.

[0028] In this invention, the granular material is a mixture of sodium polyacrylate and kaolin. Kaolin has a microporous structure, while sodium polyacrylate has a polar structure and a cross-linked network structure that has a strong adsorption effect on moisture. The combination of the two can further improve the cooling, slag reduction and harm reduction effect of the filter rod.

[0029] Preferably, the mass ratio of sodium polyacrylate to kaolin is 1:(1-3), for example, 1:1.1, 1:1.5, 1:2.0, 1:2.5 or 1:2.9.

[0030] Preferably, the material of the outer wrapping layer includes any one or a combination of at least two of the following: molded paper, polylactic acid film, or polyhydroxyalkanoate film.

[0031] Preferably, the outer diameter of the cigarette filter rod is 5-8mm and the length is 5-60mm. For example, the outer diameter can be 5.5mm, 6mm, 6.5mm, 7mm, or 7.5mm, and the length can be 6mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, or 58mm, etc.

[0032] All the specific point values ​​within the above range can be selected, and will not be elaborated on here.

[0033] In a second aspect, the present invention provides an application of the cigarette filter rod according to the first aspect in the preparation of cigarettes; Preferably, the cigarettes include conventional cigarettes or heated cigarettes.

[0034] Compared with the prior art, the present invention has the following beneficial effects: (1) The cigarette filter rod of the present invention can make the smoke condensed and intercepted by polylactic acid during the flow of the filter rod, and combined with the adsorption of water, tar and other substances in the smoke by the protrusion, which can effectively reduce the tar content and temperature of the smoke.

[0035] (2) The cigarette filter rod of the present invention can be used in conventional cigarettes or in heated cigarettes. Attached Figure Description

[0036] The above description of the present invention and the following detailed embodiments will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are merely examples of the claimed technical solutions.

[0037] Figure 1 This is a longitudinal schematic diagram of the cigarette filter rod of the present invention; Figure 2 This is a schematic cross-sectional view of the cigarette filter rod of the present invention. Detailed Implementation

[0038] To further illustrate the technical means and effects of this invention, the following description, in conjunction with embodiments and accompanying drawings, provides a further explanation of the invention. It is understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it.

[0039] The terms “comprising,” “including,” “having,” “containing,” or any other variations thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not limited to those elements and may also include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0040] "Optional" or "any one" means that the matter or event described thereafter may or may not occur, and the description includes both the possibility that the event will occur and the possibility that the event will not occur.

[0041] The indefinite articles “a” and “an” preceding an element or component of this invention do not impose any limitation on the quantity (i.e., number of occurrences) of the element or component. Therefore, “an” or “a” should be interpreted as including one or at least one, and the singular form of an element or component also includes the plural form, unless the quantity clearly refers only to the singular form.

[0042] The terms "one embodiment," "some embodiments," "exemplary," "specific example," or "some examples," etc., used in this invention refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this document, the illustrative expressions of the above terms are not necessarily directed at the same embodiment or example.

[0043] Where specific techniques or conditions are not specified in the examples, they shall be performed in accordance with the techniques or conditions described in the literature in this field, or in accordance with the product instructions. The sodium polyacrylate (CAS No.: 9003-04-7) was sourced from Sinopharm Chemical Reagent Co., Ltd. All other reagents or instruments used without specified manufacturers are conventional products that can be purchased through legitimate channels.

[0044] Example 1 This embodiment provides a cigarette filter rod with an outer diameter of 6mm and a length of 40mm. The cigarette filter rod is obtained by 25 strips of polylactic acid with a thickness of 1mm arranged side by side, gathered together, rotated 30° along the central axis, and then fixed by outer forming paper. The preparation method of the polylactic acid strip is as follows: using a 1mm thick foamed polylactic acid sheet as raw material, the polylactic acid sheet is continuously cut longitudinally at a spacing of 1mm. After cutting, the foamed polylactic acid forms pores at the cut points. After the foamed polylactic acid sheet is cut, the polylactic acid pores at the cut points rupture, and the pore area accounts for approximately 50% of the surface area of ​​the polylactic acid strip. The polylactic acid strip has a large number of pores, which effectively increases the adsorption area and can greatly improve the interception of tar and condensation of moisture in flue gas, thereby reducing harmful components and temperature in the flue gas.

[0045] The outer surface of the polylactic acid is coated with a mixture of licorice extract, chicory extract, and black tea tincture in a mass ratio of 1:3:2, and the coating thickness is 0.1 mm.

[0046] The strip-shaped polylactic acid with protrusions accounts for 50% of the total number of strip-shaped polylactic acid, and the protrusions are irregularly arranged.

[0047] The protrusion has a height of 0.5 mm and contains a mixture of sodium polyacrylate and kaolin in a mass ratio of 1:1.

[0048] Example 2 This embodiment provides a cigarette filter rod with an outer diameter of 6mm and a length of 40mm. The cigarette filter rod is obtained by 17 strips of polylactic acid with a thickness of 1.5mm arranged side by side, gathered together, rotated 20° along the central axis, and then fixed by outer forming paper. The preparation method of the strip-shaped polylactic acid is the same as in Example 1, except that the thickness of the foamed polylactic acid sheet is 1.5 mm. After the foamed polylactic acid sheet is cut, the polylactic acid pores at the cut end rupture, and the ruptured area accounts for about 60% of the surface area of ​​the polylactic acid strip.

[0049] The outer surface of the polylactic acid is coated with a mixture of licorice extract, chicory extract, and black tea tincture in a mass ratio of 1:3:2, and the coating thickness is 0.2 mm.

[0050] The protruding polylactic acid strips account for 40% of the total number of polylactic acid strips, and the protrusions are irregularly arranged. The protrusion height of each protrusion is 0.6 mm, and the protrusion contains a mixture of sodium polyacrylate and kaolin in a mass ratio of 1:2.

[0051] Example 3 This embodiment provides a cigarette filter rod with an outer diameter of 6mm and a length of 40mm. The cigarette filter rod is obtained by 13 strips of polylactic acid with a thickness of 2mm arranged side by side, gathered together, rotated 10° along the central axis, and then fixed by the outer forming paper. The preparation method of the strip-shaped polylactic acid is the same as in Example 1, except that the thickness of the foamed polylactic acid sheet is 2 mm. After the foamed polylactic acid sheet is cut, the polylactic acid pores at the cut end rupture, and the ruptured area accounts for about 66% of the surface area of ​​the polylactic acid strip.

[0052] The outer surface of the polylactic acid is coated with a mixture of licorice extract, chicory extract, and black tea tincture in a mass ratio of 1:3:2, and the coating thickness is 0.3 mm.

[0053] The strip-shaped polylactic acid with protrusions accounts for 30% of the total number of strip-shaped polylactic acid, and the protrusions are irregularly arranged. The protrusion height is 0.8 mm, and the protrusion contains a mixture of sodium polyacrylate and kaolin in a mass ratio of 1:3.

[0054] Example 4 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that in Embodiment 1 is that the raw material for preparing the strip-shaped polylactic acid is a polylactic acid membrane (without foaming treatment). That is, there are no holes on the surface of the polylactic acid membrane after cutting. The rest of the composition, structure and size are the same as those in Embodiment 1.

[0055] Example 5 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that in Embodiment 1 is that the polylactic acid outer surface does not have an adsorption coating. The rest of the composition, structure, and dimensions are the same as those in Embodiment 1.

[0056] Example 6 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that of Embodiment 1 is that the outer surface of the polylactic acid is coated with a coating of chicory extract and black tea tincture in a mass ratio of 3:2. The coating thickness is 0.1 mm. The remaining composition, structure, and dimensions are the same as those of Embodiment 1.

[0057] Example 7 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that in Embodiment 1 is that the outer surface of the polylactic acid is coated with a coating of licorice fluid extract and black tea tincture in a mass ratio of 1:2. The coating thickness is 0.1 mm. The remaining composition, structure, and dimensions are the same as in Embodiment 1.

[0058] Example 8 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that in Embodiment 1 is that the outer surface of the polylactic acid is coated with a coating of licorice fluid extract and chicory extract in a mass ratio of 1:3. The coating thickness is 0.1 mm. The remaining composition, structure, and dimensions are the same as in Embodiment 1.

[0059] Example 9 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that in Embodiment 1 is that the granular material is sodium polyacrylate, while the rest of the composition, structure, and size are the same as in Embodiment 1.

[0060] Example 10 This embodiment provides a cigarette filter rod. The only difference between the cigarette filter rod and that in Embodiment 1 is that the granular material is kaolin, while the rest of the composition, structure, and size are the same as in Embodiment 1.

[0061] Comparative Example 1 This comparative example provides a cigarette filter rod. The only difference between the cigarette filter rod and Example 1 is that the cigarette filter rod is made of strips of polylactic acid arranged side by side and parallel to the central axis, and then fixed by an outer wrapping layer. The rest of the composition, structure and size are the same as those of Example 1.

[0062] Comparative Example 2 This comparative example provides a cigarette filter rod, which differs from Example 1 only in that the strip-shaped polylactic acid does not have protrusions; the rest of the composition, structure, and dimensions are the same as in Example 1.

[0063] Test Example 1 The cigarette filter rods obtained in Examples 1-10 and Comparative Examples 1-2 were used to manufacture test cigarettes with tobacco shreds. The tar and carbon monoxide content in the mainstream smoke captured by the test cigarettes were tested, and the draw resistance of the cigarettes was also tested.

[0064] Test method: The tar content was determined according to GB / T 19609-2004, "Total particulate matter and tar for conventional analysis of cigarettes using a smoking machine". The CO content was determined according to GB / T 23356-2009, Determination of Carbon Monoxide in Gas Phase of Cigarette Smoke - Non-scattering Infrared Method. The draw resistance test was performed in accordance with GB / T 22838.5-2009 Determination of physical properties of cigarettes and filter rods - Part 5: Cigarette draw resistance and filter rod pressure drop.

[0065] The results are shown in Table 1 below.

[0066] Table 1 As shown in Table 1, the cigarette filter rods prepared in Examples 1-3 of this invention have moderate draw resistance after cigarette smoking and better adsorption effect on harmful chemical components in the smoke.

[0067] As can be seen from Example 4, when the polylactic acid surface has no pores, the filter rod has a poor adsorption effect on harmful chemical components in flue gas.

[0068] As can be seen from Example 5, when the polylactic acid outer surface is not provided with an adsorption coating, the filter rod is less effective at reducing harmful components in flue gas.

[0069] As can be seen from Examples 6-8, the coating is most effective in enhancing the sweetness of smoke, increasing the natural flavor of tobacco, reducing smoke irritation, and improving the aroma and taste of smoke only when the adsorption coating is a combination of licorice fluid extract, chicory extract and black tea tincture.

[0070] As can be seen from Examples 9-10, the placement of granular protrusions in the protrusions and the selection of granular materials affect the adsorption effect of the filter rod. In Example 10, kaolin was used as the granular material because the microporous structure of kaolin has a good adsorption effect on tar in flue gas, and its harm reduction effect is optimal.

[0071] As can be seen from Comparative Example 1, when polylactic acid is arranged in parallel, the filter rod has a poor interception effect on flue gas, which in turn affects the adsorption effect on harmful components.

[0072] As can be seen from Comparative Example 2, when the polylactic acid surface is not provided with protrusions, the harm reduction effect of the filter rod is also reduced, and the draw resistance of the cigarette is too high, which affects the sensory experience.

[0073] Test Example 2 The test cigarettes obtained in Examples 1-10 and Comparative Examples 1-2 were inserted into heated cigarette devices, heated and inhaled, and the smoke temperature was tested.

[0074] The smoke temperature test adopts the thermocouple temperature measurement method. The cigarette smoking model is simulated according to the national standard YC / T29-1996. The thermocouple is fixed 1 mm from the center of the cigarette filter outlet. The thermocouple is connected to the temperature data acquisition system to measure the temperature of the smoke at the cigarette filter outlet during smoking.

[0075] The test results are shown in Table 2.

[0076] Table 2 According to the data in Table 2, the filter rods obtained in Examples 1-3 of the present invention have excellent cooling effect and the inlet temperature of flue gas is more suitable.

[0077] As can be seen from Example 4, when there are no pores on the surface of the polylactic acid, on the one hand, the filter rod has a poor condensation effect on the moisture in the flue gas, resulting in a higher flue gas inlet temperature; on the other hand, when there are no pores on the surface of the polylactic acid, the polylactic acid loaded adsorption coating has a poor effect.

[0078] As can be seen from Example 5, when an adsorption coating is provided on the outer surface of polylactic acid, it helps to reduce the humidity of flue gas.

[0079] As can be seen from Examples 9-10, the placement of granular material in the protrusions and the selection of the granular material have a significant impact on the cooling effect of the filter rod. In Example 9, the sodium polyacrylate particles have strong water absorption properties, resulting in the optimal effect on reducing flue gas temperature.

[0080] As can be seen from Comparative Example 1, when polylactic acid is arranged in parallel, the filter rods have a poor interception effect on flue gas, which in turn affects the cooling effect.

[0081] As can be seen from Comparative Example 2, when no protrusions are provided on the surface of polylactic acid, the cooling effect of the filter rod is also reduced.

[0082] Furthermore, as shown in Tables 1 and 2, the filter rods prepared using the mixture of sodium polyacrylate and kaolin described in this invention exhibit better overall effects in reducing coke and lowering temperature.

[0083] The applicant declares that this invention illustrates a cigarette filter rod and its application through the above embodiments, but this invention is not limited to the detailed methods described above, that is, it does not mean that this invention must rely on the detailed methods described above to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials of this invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this invention.

Claims

1. A cigarette filter rod, characterized by, The cigarette filter rod is obtained by converging strips of polylactic acid together and rotating them along the central axis, and then fixing them with an outer wrapping layer; The rotation angle of each polylactic acid strip along the filter rod axis is independently 1-89°, and at least one strip of polylactic acid has at least one protrusion. By setting the protrusion on the strip of polylactic acid, the blockage of the flue gas channel caused by close contact between adjacent polylactic acid strips can be avoided. The outer surface of the polylactic acid is coated with an adsorption coating. The protrusion contains granular material inside; The strip-shaped polylactic acid is obtained by longitudinally and continuously cutting foamed polylactic acid sheets. After the polylactic acid foamed sheet is cut, the polylactic acid foam cells at the cut end rupture, forming a hole.

2. A cigarette filter according to claim 1, characterised in that, The rotation angle of a single polylactic acid strand in the filter rod along the axis of the filter rod is 10-30°.

3. The cigarette filter rod according to claim 1, characterized in that, The spacing of the cuts is 0.5-3mm.

4. The cigarette filter rod according to claim 3, characterized in that, The thickness of the foamed polylactic acid sheet is 0.2-2 mm.

5. The cigarette filter rod according to claim 3, characterized in that, The thickness of the foamed polylactic acid sheet is 0.3-1.5 mm.

6. The cigarette filter rod according to claim 1, characterized in that, The thickness of the adsorption coating is 0.05-0.3 mm.

7. The cigarette filter rod according to claim 1, characterized in that, The adsorption coating comprises any one or a combination of at least two of licorice fluid extract, chicory extract, or black tea tincture.

8. The cigarette filter rod according to claim 7, characterized in that, The adsorption coating is composed of licorice extract, chicory extract, and black tea tincture.

9. The cigarette filter rod according to claim 8, characterized in that, The mass ratio of the licorice fluid extract, chicory extract and black tea tincture is 1:(1-3):(1-3).

10. The cigarette filter rod according to claim 1, characterized in that, The number of strip-shaped polylactic acid with protrusions is 10-100% of the total number of strip-shaped polylactic acid.

11. The cigarette filter rod according to claim 1, characterized in that, The height of the protrusion is independently 10%-50% of the thickness of the polylactic acid strip.

12. The cigarette filter rod according to claim 1, characterized in that, The granular material includes any one or a combination of at least two of sodium polyacrylate, perlite, diatomaceous earth, kaolin, or montmorillonite.

13. The cigarette filter rod according to claim 12, characterized in that, The granular material is a mixture of sodium polyacrylate and kaolin.

14. The cigarette filter rod according to claim 13, characterized in that, The mass ratio of sodium polyacrylate to kaolin is 1:(1-3).

15. The cigarette filter rod according to claim 1, characterized in that, The material of the outer wrapping layer includes any one or a combination of at least two of the following: molded paper, polylactic acid film, or polyhydroxyalkanoate film.

16. The cigarette filter rod according to claim 1, characterized in that, The outer diameter of the cigarette filter rod is 5-8mm, and the length is 5-60mm.

17. The use of a cigarette filter rod according to any one of claims 1-16 in the preparation of cigarettes.

18. The application according to claim 17, characterized in that, The cigarettes include conventional cigarettes or heated cigarettes.

Images