Activated carbon composite filter rod and method for manufacturing the same

Abstract

The present application relates to cigarette filter rod technical field, especially to a kind of activated carbon composite filter rod and its preparation method.This kind of activated carbon composite filter rod, including by modified non-woven fabric and is rolled into modified adsorption section, in the opposite two sides of the modified non-woven fabric, one side is equipped with activated carbon, another side is equipped with base material essence.The application is coated activated carbon and base material essence respectively in the opposite two sides of non-woven fabric, effectively avoid the blockage of activated carbon through hole by base material essence, obtain the modified non-woven fabric with strong adsorption and considerable fragrance, the modified adsorption section prepared by this modified non-woven fabric is applied in cigarette filter, can effectively adsorb harmful substances, improve suction resistance, and release fragrance.

Description

Technical Field

[0001] This invention relates to the field of cigarette filter rod technology, and in particular to an activated carbon composite filter rod and its preparation method. Background Technology

[0002] In recent years, with tobacco consumers paying more attention to the health implications of smoking, reducing harmful components in cigarette smoke has become a key research focus for tobacco technicians. Through long-term research, the tobacco industry has made significant progress in reducing harm and enhancing flavor in cigarette filters. Currently, activated carbon is widely used in cigarette filters, and various studies have clearly shown that activated carbon can adsorb harmful substances in cigarette smoke. Current application research mainly focuses on granular activated carbon. However, the use of granular activated carbon in filters presents some problems during inhalation. For example, in ternary cavity filter rods, the activated carbon particles are concentrated near the ground due to gravity during inhalation, while the other side forms a cavity. Smoke selectively passes mainly through the cavity with lower resistance, resulting in poor smoke adsorption. Another example is binary composite filter rods where activated carbon particles are embedded in the fiber bundle. Firstly, the amount of activated carbon particles added is limited; secondly, the uniformity of particle dispersion is poor; and thirdly, the addition of nearly 10% triacetyl ester during fiber bundle formation can cause partial blockage of the micropores in the activated carbon particles, thus limiting its adsorption effect.

[0003] Patent document CN111713738A discloses a scented nonwoven fabric and its application in cigarette filter materials, including the following steps: 1. Preparation of the scenting substance to obtain a gel-like scenting substance; 2. Nonwoven fabric pretreatment: ① Pulverizing activated carbon using a high-speed pulverizer to a particle size of 200-300 mesh; ② Drying the activated carbon powder; ③ Arranging polypropylene fiber nonwovens in a closed space, rotating it through a charged rubber roller, and uniformly charging the nonwoven fabric after passing through the charged rubber roller; simultaneously loading the prepared activated carbon powder into a spray gun, with the spray gun facing the charged rubber roller. ④ Start the spraying system to spray activated carbon powder onto the surface of the nonwoven fabric. The spraying amount is 50-200 g / min, and the winding speed of the nonwoven fabric is 0.2-0.5 m / s. The activated carbon powder adheres to the nonwoven fabric under the action of electrostatic force. ⑤ Blow the nonwoven fabric after spraying with gas to blow away the activated carbon powder that is not firmly adsorbed. Then send the nonwoven fabric to the dip coating process. III. Dip coating of fragrance substances: Heat the gel-like fragrance substance in a water bath until it is in a liquid state. The water bath temperature is 80℃~150℃. Then apply it to the pretreated nonwoven fabric by dip coating.

[0004] In this application, activated carbon is first electrostatically sprayed onto a polypropylene fiber nonwoven fabric, and then a fragrance substance is coated on it. First, during the process of coating the fragrance substance, the fragrance substance fills and blocks the pores of the activated carbon. Second, the activated carbon is loaded onto the nonwoven fabric by electrostatic spraying, resulting in low loading capacity and load strength, and the activated carbon is small and easily falls off. Therefore, the adsorption effect of the filter rod in this application is still limited. Summary of the Invention

[0005] The present invention aims to solve the above problems by providing an activated carbon composite filter rod with good adsorption effect on harmful substances during the suction process and its preparation method.

[0006] The technical solution to the problem of this invention is to first provide an activated carbon composite filter rod, including a modified adsorption section made of modified non-woven fabric, wherein one side of the modified non-woven fabric is provided with activated carbon and the other side is provided with base fragrance.

[0007] The term "set up" here means that activated carbon and base fragrance can be loaded onto nonwoven fabric by any physical or chemical means, such as spraying, coating, or adhesive bonding.

[0008] In this application, activated carbon and base fragrance are coated on opposite sides of the nonwoven fabric, which effectively avoids the base fragrance from clogging the pores of the activated carbon, resulting in a modified nonwoven fabric with strong adsorption and a considerable fragrance. When the modified adsorption section made from this modified nonwoven fabric is applied to cigarette filters, it can effectively adsorb harmful substances, improve draw resistance, and release fragrance.

[0009] Because activated carbon has a strong adsorption capacity, it can adsorb not only harmful substances but also cigarette smoke, leading to a weakening of the aroma during inhalation. Therefore, in an optional embodiment, and as a preferred embodiment of the present invention, the modified adsorption section is provided with a surface fragrance. Through the combined action of adding fragrance to the base material and the surface fragrance, the problem of weakened aroma caused by excessive adsorption capacity is improved.

[0010] In the implementation of setting base fragrance and top fragrance, the components of base fragrance and top fragrance should be different to give the filter stick a layered aroma.

[0011] The base flavoring and the top flavoring are further configured such that the volatility of the base flavoring is lower than that of the top flavoring. By adjusting the volatility, a continuous aroma is provided to the filter rod while reducing the impact of the flavoring on the adsorption capacity of the activated carbon and the impact of the activated carbon on the aroma of the flavoring. Specifically, the top flavoring volatilizes outward, with a low probability of contacting the activated carbon. The high volatility of the top flavoring accelerates its escape during the inhalation process, avoiding the problem of slow escape rate leading to re-adsorption by the surface activated carbon, thus ensuring the adsorption of harmful substances by the surface activated carbon and maintaining the initial aroma of the cigarette. In contrast, the base flavoring volatilizes outward, inevitably coming into contact with the activated carbon. The low volatility of the base flavoring means that by the time it escapes, the activated carbon has already adsorbed some harmful substances, giving the activated carbon time to adsorb harmful substances. Simultaneously, the adsorption capacity of the activated carbon is relatively reduced after adsorbing harmful substances, thereby reducing the problem of excessive adsorption by the activated carbon during escape and maintaining the subsequent aroma of the cigarette.

[0012] The volatility of base fragrance and top fragrance can be adjusted in various ways, including by considering the phase, viscosity, boiling point, and solvent of the fragrance. For example, pastes, solids, mixtures with high viscosity, low purity, and high boiling point are relatively less volatile, while liquids, mixtures with low viscosity, high purity, and low boiling point are relatively more volatile. Therefore, as a preferred embodiment of the present invention, the base fragrance includes extracts and / or pastes, and the top fragrance includes essential oils and / or purified compounds with aroma. Purified compounds refer to single compounds with a purity of not less than 99%, which are usually commercially available or obtained in a laboratory through multiple purification steps. Extracts refer to mixtures obtained by directly extracting raw materials with a solvent; pastes refer to mixtures obtained by further extraction and concentration of extracts; and essential oils refer to mixtures obtained by further extraction of pastes and removal of the solvent. Therefore, the purity of the extracts, pastes, and essential oils decreases sequentially.

[0013] More preferably, the base flavoring, based on the extract and / or extract, considers components with high boiling points, including one or more of the following: *Tobacco denudata* extract, K326 tobacco extract, fig extract, loquat extract, honey, jujube extract, tree moss extract, and *Tremella fuciformis* extract. To ensure uniform mixing of these components and facilitate spraying, a solvent should also be included. Preferably, the solvent of the base flavoring is composed of propylene glycol, water, and glycerin. More preferably, the base flavoring, by weight, comprises 6-18 parts of *Tobacco denudata* extract, 7-21 parts of K326 tobacco extract, 3-9 parts of fig extract, 2-6 parts of loquat extract, 2-6 parts of honey, 2-8 parts of jujube extract, 1-5 parts of 1% tree moss extract, 5-20 parts of *Tremella fuciformis* extract, 17-49 parts of propylene glycol, 7-23 parts of water, and 2-8 parts of glycerin.

[0014] The top fragrance, based on essential oils and / or purified aromatic compounds, and considering components with low boiling points, comprises one or more of Zimbabwean tobacco absolute, dihydrodamascone, loquat absolute, rose essential oil, Virginia tobacco absolute, and methylheptenone. The solvent for the top fragrance consists of an ethanol solution and propylene glycol. More preferably, the top fragrance, by weight, comprises 2-8 parts of 1% Zimbabwean tobacco absolute, 2-6 parts of 1% dihydrodamascone, 2-6 parts of 5% loquat absolute, 1-4 parts of 0.1% rose essential oil, 3-9 parts of 1% Virginia tobacco absolute, 1-5 parts of 1% methylheptenone, 28-88 parts of 75% ethanol, and 5-20 parts of propylene glycol.

[0015] Since the nonwoven fabric turns black after adding activated carbon, there is a risk of activated carbon detaching under suction force. Therefore, as a preferred embodiment of the present invention, the modified adsorption section should be used in combination with a conventional filter rod. In this combination, the modified adsorption section is positioned between the conventional adsorption section and the tobacco segments of the cigarette, with the conventional adsorption section serving as the inhalation end and the modified adsorption section as the connecting end for the tobacco segments, thus improving the adsorption effect on harmful substances in the smoke. Furthermore, the combined use of the modified and conventional adsorption sections improves the overall mechanical properties of the filter rod. Modification and the addition of activated carbon increase the stiffness and hardness of the nonwoven fabric material, resulting in good machine performance during rolling. More preferably, the length of the modified adsorption section is less than or equal to the length of the conventional adsorption section, with the conventional adsorption section serving as the main support unit.

[0016] The conventional adsorption section can be made of any filter material available in the prior art. Preferably, the conventional adsorption section is made of a fiber material, including one or more of cellulose acetate, polylactic acid, and polypropylene fibers. Cellulose acetate is preferred.

[0017] The adhesion of activated carbon and base fragrance to non-woven fabric affects the final adsorption performance of the filter rod. Therefore, another objective of this invention is to provide a method for preparing the activated carbon composite filter rod, comprising the following steps:

[0018] S1. Prepare the base flavoring;

[0019] S2. Mix activated carbon with adhesive to obtain adhesive material;

[0020] S3. Apply adhesive to one side of the nonwoven fabric, and before drying and after dehydration, apply the base fragrance to the other side of the nonwoven fabric and dry to obtain the modified nonwoven fabric.

[0021] S4. The modified nonwoven fabric is rolled and cut to obtain the modified adsorption section.

[0022] In this application, firstly, the activated carbon is coated onto the nonwoven fabric with an adhesive, which increases the loading capacity and strength of the activated carbon and prevents it from falling off. Secondly, before drying and after dehydration, the wet activated carbon nonwoven fabric is scented with base fragrance. On the one hand, the adhesive fills and even permeates through the pores of the nonwoven fabric, strengthening the adhesion strength of the base fragrance to the other side of the nonwoven fabric. On the other hand, the pores of the activated carbon are covered by the adhesive, preventing accidental adsorption of the base fragrance by the activated carbon after it penetrates the nonwoven fabric during the fragrance coating process. Thirdly, the drying operation is reduced from two steps to one, simplifying the process.

[0023] In S2, the adhesive is selected from materials that have minimal impact on the pore size and porosity of the activated carbon after complete drying and curing. For example, materials with low decomposition temperatures can be chosen to decompose during drying or suction, releasing the pores blocked by the adhesive. Polyvinyl alcohol, for instance, becomes embrittled above 100℃ and decomposes around 200℃. Alternatively, thermally decomposable materials can be added to the adhesive to decompose during drying or suction, preventing the adhesive from forming a complete film and avoiding masking of the activated carbon pores. Examples of thermally decomposable materials include sodium bicarbonate and calcium bicarbonate.

[0024] The concentration and amount of adhesive should be limited. An increase in the proportion of adhesive relative to activated carbon will lead to a corresponding increase in the amount of activated carbon pores blocked by the adhesive. Preferably, the mass ratio of activated carbon to adhesive is 1:(1-10). When polyvinyl alcohol is used as the adhesive, preferably, a 1%-10% aqueous solution of polyvinyl alcohol is selected.

[0025] In S3, the method of adding the base fragrance is not limited, but it is preferable to use an atomizing nozzle for spraying to improve the adhesion strength and spray uniformity of the fragrance. The atomizing nozzle pressure is preferably 0.01MPa-0.5MPa, more preferably 0.05MPa-0.2MPa, and most preferably 0.1MPa. The amount of base fragrance is not limited, but it is preferably 5%-15% of the nonwoven fabric mass, and most preferably 10%.

[0026] During drying, the preferred drying temperature is 80℃-105℃, which ensures that the adhesive becomes brittle while reducing the thermal volatilization of the base fragrance.

[0027] In S4, when the modified nonwoven fabric is rolled and cut, a paper-nose bar machine is preferred for rolling, and a pressure roller is used. This not only reduces the problem of excessive pressure on the nonwoven fabric during the rolling process, which can lead to densification issues and affect the adsorption capacity of activated carbon, but also improves the circumferential stability of the modified adsorption section obtained from the roll. The pressure roller width is preferably 0.2mm-2.0mm.

[0028] In an optional embodiment, the method further includes the following step: after preparing the top fragrance, spraying the top fragrance onto the modified adsorption section.

[0029] Preferably, during the rolling process of the modified nonwoven fabric, the surface fragrance is added to the side without coated activated carbon while rolling. After the surface fragrance is added, drying is not required, thus avoiding the loss of highly volatile surface fragrance during the drying process.

[0030] The amount of fragrance added should not be too high to avoid clogging the pores of the activated carbon. Preferably, the amount of fragrance added is 0.1%-3% of the nonwoven fabric mass, and more preferably 1%. To improve the uniformity of fragrance addition, it is preferable to add fragrance through an atomizing chamber, ensuring the uniformity of volatile fragrance addition while reducing fragrance loss. The pressure of the atomizing nozzle is preferably 0.01MPa-0.5MPa, more preferably 0.05MPa-0.2MPa, and most preferably 0.1MPa.

[0031] In an optional embodiment, the method further includes the following step: after rolling the fiber material into a conventional adsorption section using conventional processes, the modified adsorption section and the conventional adsorption section are then combined into a binary composite. Binary composite is a conventional technique in the field of cigarette filter rod preparation, and is generally obtained by axially connecting the modified adsorption section and the conventional adsorption section and then wrapping them with tipping paper.

[0032] The beneficial effects of this invention are:

[0033] 1. This application provides a composite filter rod in which activated carbon and base fragrance are coated on opposite sides of a nonwoven fabric, effectively avoiding the blockage of the activated carbon pores by the base fragrance, and obtaining a modified nonwoven fabric with strong adsorption and considerable fragrance. When the modified adsorption section made from this modified nonwoven fabric is applied in a cigarette filter, it can effectively adsorb harmful substances, improve draw resistance, and release fragrance.

[0034] 2. This application loads activated carbon onto non-woven fabric, increasing the amount of activated carbon used in the filter rod and significantly improving the filter rod's ability to adsorb harmful substances. At the same time, it uses secondary fragrance replenishment to improve the problem of weakened smoke aroma caused by excessive adsorption capacity.

[0035] 3. In this application, the activated carbon modified adsorption section is combined with the cellulose acetate adsorption section in the form of a whole filter rod. When the flue gas passes through the filter rod, it passes through the filter rod relatively uniformly, which improves the disadvantage of selective passage of flue gas through the particle-free space caused by adding activated carbon material in the existing three-dimensional cavity form and adding activated carbon particles in the form of fiber bundle.

[0036] 4. This application provides a method for preparing a composite filter rod. Activated carbon is coated onto a non-woven fabric using an adhesive, which increases the loading capacity and strength of the activated carbon and prevents it from detaching. Simultaneously, before drying, the wet activated carbon non-woven fabric is scented with a base fragrance. This strengthens the adhesion of the base fragrance through the adhesive, and the adhesive also covers the pores of the activated carbon, preventing accidental adsorption of the base fragrance by the activated carbon during the fragrance spraying or coating process. All these measures further ensure and improve the adsorption performance of the prepared composite filter rod.

[0037] 5. In this application, the modified nonwoven fabric is rolled using a pressing process, which improves the stability of the filter rod's suction resistance and circumferential properties. Detailed Implementation

[0038] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described, but the present invention is not limited to these embodiments.

[0039] Example 1

[0040] An activated carbon composite filter rod includes a modified adsorption section made of modified nonwoven fabric and a conventional adsorption section made of cellulose acetate. The length of the modified adsorption section is shorter than that of the conventional adsorption section. On opposite sides of the modified nonwoven fabric, one side has activated carbon and the other side has a base fragrance. The modified adsorption section also has a surface fragrance, and the volatility of the base fragrance is lower than that of the surface fragrance.

[0041] This activated carbon composite filter rod is prepared through the following steps:

[0042] S1. Preparation of base flavoring: According to the mass ratio, mix 8 parts of red tobacco extract, 10 parts of K326 tobacco extract, 6 parts of fig extract, 4 parts of loquat extract, 3 parts of honey, 4 parts of jujube extract, 3 parts of 1% tree moss extract, 12 parts of tremella extract, 30 parts of propylene glycol, 17 parts of water, and 3 parts of glycerin evenly to obtain the base flavoring.

[0043] S2. Mix activated carbon with adhesive to obtain adhesive: Prepare a 5% polyvinyl alcohol aqueous solution. Add 3 parts activated carbon to 10 parts polyvinyl alcohol aqueous solution according to the mass ratio, stir evenly, and obtain adhesive.

[0044] S3. Apply a uniform coating of adhesive to the front side of the nonwoven fabric, using activated carbon at 80% of the fabric's mass. After coating, send the nonwoven fabric into a vacuum dehydration device for dehydration to reduce moisture content while avoiding complete drying. Then, apply a base fragrance to the back side of the nonwoven fabric, using 10% of its mass, using an atomizing nozzle at a pressure of 0.1 MPa. After spraying, dry the fabric at 90°C to obtain the modified nonwoven fabric.

[0045] S4. Preparation of Top Fragrance Essence: According to the mass parts, mix 4 parts of % Zimbabwe tobacco absolute oil, 3 parts of 1% dihydrodamascone, 3 parts of 5% loquat absolute oil, 2 parts of 0.1% rose essential oil, 6 parts of 1% Virginia tobacco absolute oil, 3 parts of 1% methylheptenone, 69 parts of 75% ethanol, and 10 parts of propylene glycol evenly to obtain the top fragrance essence.

[0046] S5. The modified nonwoven fabric is wound using a paper-tip rod machine, where the embossing roller is replaced with a yarn-pressing roller with a yarn width of 1.0 mm. The activated carbon nonwoven fabric, after being cut, is then scented in an atomization chamber to add surface fragrance. The amount of surface fragrance is 1% of the nonwoven fabric mass, and the atomization nozzle pressure is 0.1 MPa, resulting in a modified adsorption section with secondary fragrance addition.

[0047] S6. Roll up the cellulose acetate filter rods according to conventional processes to obtain the conventional adsorption section.

[0048] S7. A 10mm modified adsorption section and a 15mm conventional adsorption section are combined in a binary composite to obtain a composite filter rod.

[0049] Example 2

[0050] This embodiment is basically the same as embodiment 1, except that the volatility of the base fragrance is greater than that of the surface fragrance.

[0051] This activated carbon composite filter rod is prepared through the following steps:

[0052] The preparation steps are basically the same as those in Example 1, with the only difference being:

[0053] In step S1, the base flavoring is prepared by mixing 4 parts of % Zimbabwean tobacco essential oil, 3 parts of 1% dihydrodamascone, 3 parts of 5% loquat essential oil, 2 parts of 0.1% rose essential oil, 6 parts of 1% Virginia tobacco essential oil, 3 parts of 1% methylheptenone, 69 parts of 75% ethanol, and 10 parts of propylene glycol evenly to obtain the base flavoring.

[0054] In step S4, the flavoring essence is prepared by mixing 8 parts of red tobacco extract, 10 parts of K326 tobacco extract, 6 parts of fig extract, 4 parts of loquat extract, 3 parts of honey, 4 parts of jujube extract, 3 parts of 1% tree moss extract, 12 parts of tremella extract, 30 parts of propylene glycol, 17 parts of water, and 3 parts of glycerin evenly to obtain the flavoring essence.

[0055] Example 3

[0056] This embodiment is basically the same as embodiment 1, except that it does not contain any surface fragrance.

[0057] This activated carbon composite filter rod is prepared through the following steps:

[0058] S1. Preparation of base flavoring: According to the mass ratio, mix 8 parts of red tobacco extract, 10 parts of K326 tobacco extract, 6 parts of fig extract, 4 parts of loquat extract, 3 parts of honey, 4 parts of jujube extract, 3 parts of 1% tree moss extract, 12 parts of tremella extract, 30 parts of propylene glycol, 17 parts of water, and 3 parts of glycerin evenly to obtain the base flavoring.

[0059] S2. Mix activated carbon with adhesive to obtain adhesive: Prepare a 5% polyvinyl alcohol aqueous solution. Add 3 parts activated carbon to 10 parts polyvinyl alcohol aqueous solution according to the mass ratio, stir evenly, and obtain adhesive.

[0060] S3. Apply a uniform coating of adhesive to the front side of the nonwoven fabric, using activated carbon at 80% of the fabric's mass. After coating, send the nonwoven fabric into a vacuum dehydration device for dehydration to reduce moisture content while avoiding complete drying. Then, apply a base fragrance to the back side of the nonwoven fabric, using 10% of its mass, using an atomizing nozzle at a pressure of 0.1 MPa. After spraying, dry the fabric at 90°C to obtain the modified nonwoven fabric.

[0061] S4. The modified nonwoven fabric is rolled up using a paper nozzle bar machine and a pressing roller, wherein the pressing roller has a pressing width of 1.0 mm, and then the modified adsorption section is obtained by pressing and cutting.

[0062] S5. Roll up the cellulose acetate filter rods according to conventional processes to obtain the conventional adsorption section.

[0063] S6. A 10m modified adsorption section and a 15mm conventional adsorption section are combined in a binary composite to obtain a composite filter rod.

[0064] Example 4

[0065] This embodiment is basically the same as Embodiment 1, except that the length of the modified adsorption section is greater than that of the conventional adsorption section.

[0066] This activated carbon composite filter rod is prepared through the following steps:

[0067] The preparation steps are basically the same as those in Example 1, except that in S7, a 15mm modified adsorption section and a 10mm conventional adsorption section are combined in a binary manner to obtain a composite filter rod.

[0068] Example 5

[0069] This embodiment is basically the same as Embodiment 1, except that the preparation method is different.

[0070] In step S2, a 1% polyvinyl alcohol aqueous solution is prepared. 3 parts activated carbon are added to 3 parts polyvinyl alcohol aqueous solution according to their mass ratio, and the mixture is stirred until homogeneous to obtain the adhesive.

[0071] Example 6

[0072] This embodiment is basically the same as Embodiment 1, except that the preparation method is different.

[0073] In step S2, a 10% polyvinyl alcohol aqueous solution is prepared. 3 parts activated carbon are added to 30 parts of the polyvinyl alcohol aqueous solution according to their mass ratio, and the mixture is stirred until homogeneous to obtain the adhesive.

[0074] Example 7

[0075] This embodiment is basically the same as Embodiment 1, except that the preparation method is different.

[0076] In step S5, a paper nozzle machine and an embossing roller are used to roll up the modified nonwoven fabric.

[0077] Example 8

[0078] An activated carbon composite filter rod includes a modified adsorption section made of modified nonwoven fabric and a conventional adsorption section made of cellulose acetate. The length of the modified adsorption section is shorter than that of the conventional adsorption section. On opposite sides of the modified nonwoven fabric, one side has activated carbon and the other side has a base fragrance. The modified adsorption section also has a surface fragrance, and the volatility of the base fragrance is lower than that of the surface fragrance.

[0079] This activated carbon composite filter rod is prepared through the following steps:

[0080] S1. Preparation of base flavoring: According to the mass ratio, mix 8 parts of red tobacco extract, 10 parts of K326 tobacco extract, 6 parts of fig extract, 4 parts of loquat extract, 3 parts of honey, 4 parts of jujube extract, 3 parts of 1% tree moss extract, 12 parts of tremella extract, 30 parts of propylene glycol, 17 parts of water, and 3 parts of glycerin evenly to obtain the base flavoring.

[0081] S2. Mix activated carbon with adhesive to obtain adhesive: Prepare a 5% polyvinyl alcohol aqueous solution. Add 3 parts activated carbon to 10 parts polyvinyl alcohol solution according to the mass ratio, stir evenly, and obtain adhesive.

[0082] S3. Apply a uniform coating of adhesive to the front side of the nonwoven fabric, using activated carbon at 80% of the fabric's mass. Before the adhesive dries, apply a base fragrance to the back side of the nonwoven fabric, using 10% of the fabric's mass. Use an atomizing nozzle with a pressure of 0.1 MPa. Dry the fabric after spraying at 90℃ to obtain the modified nonwoven fabric.

[0083] S4. The modified nonwoven fabric is rolled up using a paper nozzle bar machine and a pressing roller, wherein the pressing roller has a pressing width of 1.0 mm, and then the modified adsorption section is obtained by pressing and cutting.

[0084] S5. Preparation of Top Fragrance Essence: According to the mass parts, mix 4 parts of % Zimbabwe tobacco absolute oil, 3 parts of 1% dihydrodamascone, 3 parts of 5% loquat absolute oil, 2 parts of 0.1% rose essential oil, 6 parts of 1% Virginia tobacco absolute oil, 3 parts of 1% methylheptenone, 69 parts of 75% ethanol, and 10 parts of propylene glycol evenly to obtain the top fragrance essence.

[0085] S6. The modified adsorption section is atomized and scented. The amount of fragrance is 1% of the mass of the nonwoven fabric, and the pressure of the atomizing nozzle is 0.1 MPa. After spraying, the modified adsorption section with secondary fragrance is obtained directly.

[0086] S7. Roll up the cellulose acetate filter rods according to conventional processes to obtain the conventional adsorption section.

[0087] S8. A 10mm modified adsorption section and a 15mm conventional adsorption section are combined in a binary composite to obtain a composite filter rod.

[0088] Comparative Example 1

[0089] This comparative example is basically the same as Example 1, except that it does not contain base fragrance and surface fragrance.

[0090] This activated carbon composite filter rod is prepared through the following steps:

[0091] S1. Mix activated carbon with adhesive to obtain adhesive: Prepare a 5% polyvinyl alcohol aqueous solution. Add 3 parts activated carbon to 10 parts polyvinyl alcohol aqueous solution according to the mass ratio, stir evenly, and obtain adhesive.

[0092] S2. Apply a uniform coating of adhesive to the front side of the nonwoven fabric, with activated carbon accounting for 80% of the nonwoven fabric mass; after coating, dry the fabric at a temperature controlled at 90℃ to obtain the modified nonwoven fabric.

[0093] S3. The modified nonwoven fabric is rolled using a paper-stick machine, wherein the embossing roller is replaced with a yarn pressing roller, and the yarn pressing width of the yarn pressing roller is 1.0mm.

[0094] S4. Roll up the cellulose acetate filter rods according to conventional processes to obtain the conventional adsorption section.

[0095] S5. A 10mm modified adsorption section and a 15mm conventional adsorption section are combined in a binary composite to obtain a composite filter rod.

[0096] Comparative Example 2

[0097] This embodiment is basically the same as Embodiment 1, except that activated carbon is not included.

[0098] This activated carbon composite filter rod is prepared through the following steps:

[0099] S1. Preparation of base flavoring: According to the mass ratio, mix 8 parts of red tobacco extract, 10 parts of K326 tobacco extract, 6 parts of fig extract, 4 parts of loquat extract, 3 parts of honey, 4 parts of jujube extract, 3 parts of 1% tree moss extract, 12 parts of tremella extract, 30 parts of propylene glycol, 17 parts of water, and 3 parts of glycerin evenly to obtain the base flavoring.

[0100] S2. Apply a base fragrance to the nonwoven fabric, with the amount of base fragrance being 10% of the nonwoven fabric mass. Spraying is performed using an atomizing nozzle with a pressure of 0.1 MPa. After spraying, the fabric is dried at a temperature controlled at 90℃ to obtain the modified nonwoven fabric.

[0101] S3. Preparation of Top Fragrance Essence: According to the mass parts, mix 4 parts of % Zimbabwe tobacco absolute oil, 3 parts of 1% dihydrodamascone, 3 parts of 5% loquat absolute oil, 2 parts of 0.1% rose essential oil, 6 parts of 1% Virginia tobacco absolute oil, 3 parts of 1% methylheptenone, 69 parts of 75% ethanol, and 10 parts of propylene glycol evenly to obtain the top fragrance essence.

[0102] S4. The modified nonwoven fabric is wound using a paper-tip rod machine, where the embossing roller is replaced with a yarn-pressing roller with a yarn width of 1.0 mm. The activated carbon nonwoven fabric, after being cut, is then scented in an atomization chamber with added surface fragrance. The amount of surface fragrance is 1% of the nonwoven fabric mass, and the atomization nozzle pressure is 0.1 MPa, resulting in a modified adsorption section with secondary fragrance addition.

[0103] S5. Roll up the cellulose acetate filter rods according to conventional processes to obtain the conventional adsorption section.

[0104] S6. A 10mm modified adsorption section and a 15mm conventional adsorption section are combined in a binary composite to obtain a composite filter rod.

[0105] Comparative Example 3

[0106] This comparative example is basically the same as Example 1, except that activated carbon and base fragrance are sequentially provided on opposite sides of the modified nonwoven fabric.

[0107] This activated carbon composite filter rod is prepared through the following steps:

[0108] The preparation steps are basically the same as those in Example 1, except that in step S3, an adhesive is evenly coated on the front and back sides of the nonwoven fabric, and the total amount of activated carbon used on both sides is 80% of the mass of the nonwoven fabric; before the adhesive dries, a base fragrance is coated on the front and back sides of the nonwoven fabric, and the total amount of base fragrance used on both sides is 10% of the mass of the nonwoven fabric.

[0109] Comparative Example 4

[0110] This comparative example is basically the same as Example 1, except that: the modified nonwoven fabric has base fragrance and activated carbon arranged in sequence on opposite sides.

[0111] This activated carbon composite filter rod is prepared through the following steps:

[0112] The preparation steps are basically the same as those in Example 1, except that in step S3, the base fragrance is evenly coated on the front and back of the nonwoven fabric, and the total amount of base fragrance on both sides is 10% of the mass of the nonwoven fabric; then the adhesive is coated on the front and back of the nonwoven fabric, and the total amount of activated carbon on both sides is 80% of the mass of the nonwoven fabric.

[0113] Comparative Example 5

[0114] This comparative example is basically the same as Example 1, except that the preparation method is different.

[0115] In step S3, an adhesive is evenly coated onto the front side of the nonwoven fabric, with activated carbon accounting for 80% of the fabric's mass. The coated fabric is then dried at 90°C. Next, a base fragrance is coated onto the back side of the nonwoven fabric, with the base fragrance accounting for 10% of the fabric's mass. This is done using an atomizing nozzle at a pressure of 0.1 MPa. After coating, the fabric is dried at 90°C to obtain the modified nonwoven fabric.

[0116] Filter rod adsorption test

[0117] The filter rods prepared in the examples and comparative examples, as well as a 25mm cellulose acetate filter rod as a blank example, were connected to tobacco segments to make cigarettes. The cigarettes were placed under conditions of 22±1℃ and 60%±2% relative humidity for 48h for equilibration. Then, the total particulate matter in the cigarette smoke was detected and calculated according to the method in "YC / T 29-1996 Determination of Total Particulate Matter and Tar by a Smoking Machine for Conventional Analysis of Cigarettes". The results are shown in Table 1 below.

[0118] Filter rod physical testing

[0119] Physical tests were performed on the filter rods prepared in some embodiments, with 500 rods tested in each group, and statistical analysis was conducted. Specifically, the draw resistance was tested according to the method in GB / T 22838.5-2009 "Determination of Physical Properties of Cigarettes and Filter Rods - Part 5: Cigarette Draw Resistance and Filter Rod Pressure Drop", and the CPK was calculated. The circumference was calculated according to the method in GB / T 22838.13-2009 "Determination of Physical Properties of Cigarettes and Filter Rods - Part 13: Filter Rod Roundness", and the CPK was also calculated. The calculation results are shown in Table 1 below.

[0120] Suction Evaluation

[0121] After the filter rods prepared in the examples and comparative examples were connected with tobacco segments to make cigarettes, the smokers were asked to conduct smoking evaluations. The evaluation results are shown in Table 1 below.

[0122] Table 1.

[0123] sample Total particulate matter (mg / vial) Suction CPK Circumferential CPK Evaluation results Example 1 13.98 0.886 1.053 The mouth is clean, rich, and has a moderate strength. Example 2 16.02 / / There was a slight residue in the mouth, the aroma was weak, and the strength was slightly low. Example 3 13.42 / / The smoke is clean to the mouth, has a mild aroma, lacks richness, and has a moderate strength. Example 4 12.55 / 0.957 The mouth feels clean, the aroma is mild, and the strength is slightly weak. Example 5 14.32 / / / Example 6 15.06 / / / Example 7 18.97 0.495 0.813 The mouth is clean, the texture is good, but the strength is slightly weak. Example 8 13.47 / / Clean mouth, faint smell of tobacco Comparative Example 1 13.11 0.879 1.051 The mouth feels clean, the aroma is mild, and the strength is slightly weak. Comparative Example 2 21.41 0.705 0.842 There are residues in the oral cavity, the texture is rich, and the strength is moderate. Comparative Example 3 18.97 / / Slight residue remains in the oral cavity; rich in flavor; moderate intensity. Comparative Example 4 16.75 / / Slight residue remains in the oral cavity; good richness; slightly strong effect. Comparative Example 5 15.88 / / Slight residue remains in the mouth, lacking richness, but with moderate strength. Blank example 21.75 / / /

[0124] As shown in Table 1, comparing Example 1 and Comparative Examples 1-4, it can be seen that by separately applying activated carbon and base fragrance to both sides of the nonwoven fabric, compared to sequentially coating activated carbon and base fragrance, the adsorption capacity and aroma extraction of the filter tip can be effectively improved. Comparative Example 1 shows little difference in draw resistance and circumferential stability compared to Example 1, but the sensory quality of Example 1 is higher than that of Comparative Example 1. Comparative Example 2 shows a certain impact on draw resistance and circumferential stability compared to Example 1, while the sensory quality of Example 1 is higher than that of Comparative Example 2. Comparing Example 1 and Comparative Example 5, it can be seen that coating the base fragrance before the adhesive dries during the preparation process can improve adsorption capacity and aroma extraction.

[0125] Comparative examples 1 and 2 show that by specifically adjusting the volatility of the base fragrance to be lower than that of the surface fragrance, the adsorption performance and aroma extraction of the filter rod can be effectively improved. Comparative examples 1 and 3 show that secondary fragrance enhancement on the modified adsorption section improves aroma extraction without affecting adsorption performance. Comparative examples 1 and 4 show that the lengths of the modified and conventional adsorption sections affect circumferential stability. Comparative examples 1, 5, and 6 show that the composition and amount of the adhesive have a certain impact on adsorption performance. Comparative examples 1 and 7 show that using a pressure roller during the winding process of the modified nonwoven fabric has a positive impact on the adsorption performance, suction resistance, and circumferential stability of the filter rod.

[0126] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. An activated carbon composite filter rod, characterized in that: It includes a modified adsorption section made of modified nonwoven fabric, wherein one side of the modified nonwoven fabric is provided with activated carbon and the other side is provided with base fragrance. The activated carbon composite filter rod is prepared by the following steps: S1. Prepare the base flavoring; S2. Mix activated carbon with an adhesive to obtain an adhesive; the adhesive includes a material with a low decomposition temperature and a thermally decomposable material, wherein the material with a low decomposition temperature is polyvinyl alcohol, and the thermally decomposable material is selected from sodium bicarbonate and calcium bicarbonate; S3. Apply adhesive to one side of the nonwoven fabric, and before the adhesive dries, apply the base fragrance to the other side of the nonwoven fabric. At this time, the pores of the activated carbon are covered by the adhesive to prevent the activated carbon from adsorbing the base fragrance. Then dry to obtain the modified nonwoven fabric. S4. The modified nonwoven fabric is rolled and cut to obtain the modified adsorption section.

2. The activated carbon composite filter rod according to claim 1, characterized in that: The modified adsorption section is provided with a fragrance.

3. The activated carbon composite filter rod according to claim 2, characterized in that: The volatility of the base fragrance is less than that of the surface fragrance.

4. The activated carbon composite filter rod according to claim 3, characterized in that: The base fragrance includes extracts and / or pastes, and the top fragrance includes essential oils and / or purified compounds with aroma.

5. The activated carbon composite filter rod according to claim 1, characterized in that: The composite filter rod also includes a conventional adsorption section disposed between the modified adsorption section and the tobacco section of the cigarette; the conventional adsorption section is made of fiber material, which includes one or more of cellulose acetate, polylactic acid, and polypropylene fibers.

6. The activated carbon composite filter rod according to claim 5, characterized in that: The length of the modified adsorption section is less than or equal to the length of the conventional adsorption section.

7. The activated carbon composite filter rod according to claim 1, characterized in that: The adhesive comprises a polyvinyl alcohol aqueous solution with a mass concentration of 1%-10%.

8. The activated carbon composite filter rod according to claim 1, characterized in that: The mass ratio of the activated carbon to the adhesive is 1:(1-10).

9. The activated carbon composite filter rod according to claim 1, characterized in that: The wire is wound using a pressure roller.