WO2023092854A1 - High-efficiency tar-reducing cigarette filter, and preparation method therefor and application thereof - Google Patents

Abstract

A high-efficiency tar-reducing cigarette filter, and a preparation method therefor and an application thereof. The cigarette filter comprises: a smoke inlet (1), a smoke outlet (2), an outer housing (3), and an inner housing (4) sleeved inside the outer housing (3); the outer housing (3) comprises a first outer housing and a second outer housing connected to each other; the cavity between the first outer housing and the inner housing (4) forms a first smoke channel (5); the cavity inside the second outer housing forms a second smoke channel (6); one end of the inner housing (4) is connected to one end of the first outer housing by means of a connecting surface; the smoke inlet (1) is disposed on the connecting surface and communicated with the first smoke channel (5); the smoke outlet (2) is communicated with the second smoke channel (6); the side wall of the second outer housing is provided with an air inlet (7); smoke passes through the smoke inlet (1) and the first smoke channel (5) in sequence, is mixed, in the second smoke channel (6), with the air flowing in from the air inlet (7), and then finally flows out of the filter through the smoke outlet (2).

Description

A high-efficiency tar-reducing cigarette filter and its preparation method and application

This application claims the priority of the Chinese patent application submitted to the China Patent Office on November 29, 2021, the application number is 202111434707.X, and the invention title is "A high-efficiency tar reduction cigarette filter and its preparation method and application", The entire contents of which are incorporated by reference in this application.

technical field

The application relates to a high-efficiency tar-reducing cigarette filter and its preparation method and application, belonging to the technical field of tobacco.

Background technique

At present, there are a wide variety of cigarette products on the market. Generally, ordinary heat-not-burn electronic cigarettes include an aerosol generating matrix composed of shredded tobacco that generates composite aerosol and a filter tip for filtering out some harmful substances in the composite aerosol.

At present, in order to improve the filtering effect, the outer casing of the filter is often filled with high-efficiency adsorption materials such as activated carbon as the core. Although such a setting can filter more harmful substances to a certain extent, it will improve the filtering ability. Enhance the overall absorption resistance of the filter; in addition, due to the support of the core, during the suction process, the existence of the core will cause a change in the stress of the outer shell, which will cause deformation and increase the suction resistance. Therefore, in order to reduce the outer shell The deformation of the filter usually requires the outer shell of the filter to be made of hard material. However, the hard material leads to poor user experience, and it is difficult to completely avoid the deformation and increase the suction resistance; during the production process, the core and the outer shell need to be separated. Assembly, the process is cumbersome, and automatic production cannot be realized.

In order to solve the above problems, the applicant's Chinese patent CN109938401 proposed an aerosol generating device, which can reduce the suction resistance, but the effect on reducing coke and harm still needs to be improved.

Contents of the invention

According to various embodiments of the present application, the present application proposes a high-efficiency tar reduction filter for cigarettes and its preparation method and application. The filter tip for cigarettes can not only greatly reduce the drag resistance, but also ensure a certain smoke concentration and retain the aroma components; in addition, it greatly reduces harmful substances in the smoke, such as tar, and can effectively reduce the concentration of carbon monoxide in the smoke. concentration, and can reduce the flue gas temperature.

According to one aspect of the present application, there is provided a high-efficiency tar-reducing filter for cigarettes, which includes: a smoke inlet, a smoke outlet, an outer shell, and an inner shell sleeved inside the outer shell, the outer shell The body includes a connected first outer shell and a second outer shell, the cavity between the first outer shell and the inner shell forms a first flue gas channel, and the cavity inside the second outer shell forms a first smoke channel. Two flue gas passages, one end of the inner casing is connected to one end of the first outer casing through a connecting surface, the smoke inlet is arranged on the connecting surface and communicates with the first flue gas passage, The smoke outlet communicates with the second smoke passage, and the side wall of the second outer shell is provided with an air inlet;

The smoke passes through the smoke inlet and the first smoke channel in sequence, and after being mixed with the air flowing in from the air inlet in the second smoke channel, finally flows out of the filter through the smoke outlet.

Optionally, the ratio of the distance between the center of the air inlet and the smoke outlet to the length of the outer casing is (0.2-0.6):1.

Optionally, the ratio of the area of the air inlet to the smoke inlet is (50-650):1, preferably (100-400):1.

Optionally, the ratio of the area of the smoke outlet to the area of the smoke inlet is (55-145):1, preferably 126.7:1.

Optionally, the end of the inner casing away from the smoke inlet is a closed end, a buffer chamber is formed inside the inner casing, and the smoke inlet is arranged between the connecting surface and the inner casing of the connection.

Optionally, the ratio of the lengths of the inner shell to the outer shell is (0.3-0.7):1, preferably 0.5:1.

Optionally, the ratio of the inner diameter of the outer casing to the width of the first flue gas channel is (3-8):1, preferably 5.39:1.

According to another aspect of the present application, there is provided a composite material for preparing the cigarette filter described in any one of the above, which includes: 30-50 parts of styrenic block copolymer, 15-30 parts of polypropylene 30-40 parts of mineral oil and 0.2-0.7 parts of antioxidant.

Preferably, the composite material includes: 42 parts of styrenic block copolymer, 22.5 parts of polypropylene, 35 parts of mineral oil and 0.5 part of antioxidant.

Optionally, the styrenic block copolymer is selected from styrene-ethylene-propylene-styrene block copolymer or styrene-ethylene-butadiene-styrene block copolymer, preferably styrene- Ethylene-butadiene-styrene block copolymer.

Optionally, the mineral oil is at least one selected from white oil, pine tar and paraffin oil, preferably paraffin oil.

Optionally, the antioxidant is selected from 2,6-di-tert-butyl-p-cresol, 4,4'-di-tert-octyldiphenylamine and tetrakis[β-(3,5-di-tert-butyl-4 At least one of -hydroxyphenyl)propionate]pentaerythritol esters, preferably tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol esters.

By adding styrene-based block copolymers, it has high stability, low molding temperature requirements, good plasticity, excellent fluidity, good processability, and excellent low temperature resistance.

By adding polypropylene, the transparency is improved, and the density is low, the processability is good, and it has excellent impact resistance and chemical corrosion resistance.

By adding mineral oil with high solubility, it has excellent compatibility with other components, and improves the low temperature resistance of the filter.

By adding antioxidants and reacting with other components to cross-link, the anti-oxidative degradation ability of the filter in the process of manufacturing, processing, storage and application is improved.

According to another aspect of the present application, a method for preparing a filter for cigarettes is provided, which includes the following steps:

(1) raw material melting, described raw material is the above-mentioned composite material;

(2) Injection molding: using injection molding equipment to inject molten raw materials into a mold, and cooling and molding after maintaining pressure to obtain the cigarette filter, wherein the barrel temperature of the injection molding equipment is divided into at least two stages.

Optionally, the feeding temperature of the barrel in the injection molding equipment is 160-180°C, the temperature in the front section is 170-190°C, the temperature in the back section is 180-195°C, and the nozzle temperature is 200-220°C; and/or or

The injection pressure of the injection molding equipment is 1.5-4.5 MPa, the holding pressure is 50-70% of the injection pressure, and the back pressure is 0.3-1.1 MPa; and/or

The cooling time is not more than 10s.

By controlling the temperature of each position of the barrel in the injection molding equipment, the fluidity and viscosity of the melted material are ensured, so that the processability is good, and defects such as cracks, internal stress or cold marks in the processed filter tip are avoided.

By controlling the injection pressure of the injection molding equipment, the wall thickness and density of the filter tip are uniform, while reducing internal stress and shortening the molding cycle; by controlling the holding pressure, the density uniformity of the filter tip is further ensured, and the shrinkage of the filter tip can be reduced rate; by controlling the back pressure, reducing the gas in the melted material and improving the quality of the filter.

According to still another aspect of the present application, a cigarette is provided, which includes a connected smoking part and a filter, the smoking part is used to generate smoke, and the filter is selected from any one of the filters described above.

Wherein, the cigarette may be a traditional cigarette or a heat-not-burn cigarette.

The beneficial effects that this application can produce include but are not limited to:

1. The cigarette filter tip provided by this application, by setting the first smoke channel and the second smoke channel both have a cavity structure, after the smoke enters the filter tip, it flows out of the filter tip after passing through the cavity structure, greatly reducing the suction resistance At the same time, it can also ensure a certain smoke concentration and retain the aroma components; the first smoke channel is formed between the first outer shell and the inner shell, and the smoke inlet is connected with the first smoke channel, so that When the flue gas flows through the first flue gas channel, it collides with the shell wall to generate aerosol deposition, thereby greatly reducing harmful substances in the flue gas such as tar; in addition, by opening the side wall of the second outer shell The air inlet can fully mix the flue gas and air in the second flue gas channel, which can dilute the flue gas and effectively reduce the concentration of carbon monoxide in the flue gas. Temperature, the lowering of the temperature makes the particulate matter in the flue gas further deposit on the inner wall of the second flue gas channel, further reducing the harmful substances in the flue gas.

2. The composite material for cigarette filters provided by this application has good fluidity and formability after melting, is easy to injection molding, and has a wide temperature range (-30°C to 80°C), so it can be used in high-temperature smoke It will not be deformed under the action of the filter, and the processed filter tip has good elasticity, and it can be directly used in a cigarette machine without deformation.

3. The method for preparing the cigarette filter provided in this application is integrally formed by injection molding, the preparation process is simple, no secondary assembly is required, and the production efficiency is high.

Description of drawings

The drawings described here are used to provide a further understanding of the application and constitute a part of the application. The schematic embodiments and descriptions of the application are used to explain the application and do not constitute an improper limitation to the application. In the attached picture:

Fig. 1 is a schematic diagram of a cigarette filter related to an embodiment of the present application.

List of parts and reference numbers:

1. Smoke inlet; 2. Smoke outlet; 3. Outer shell; 4. Inner shell; 5. First smoke channel; 6. Second smoke channel; 7. Air inlet.

Implementation

In order to explain the overall concept of the present application more clearly, the following detailed description will be given by way of examples in combination with the accompanying drawings.

In order to better understand the above-mentioned purpose, features and advantages of the present application, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

In the following description, many specific details are set forth in order to fully understand the application, but the application can also be implemented in other ways different from those described here, therefore, the protection scope of the application is not limited by the specific details disclosed below. EXAMPLE LIMITATIONS.

In addition, in the description of the present application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal" ", "Top", "Bottom", "Inner", "Outer", "Axial", "Radial", "Circumferential" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings , is only for the convenience of describing the present application and simplifying the description, but does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of these features. In the description of the present application, "plurality" means two or more, unless otherwise specifically defined.

In this application, terms such as "installation", "connection", "connection" and "fixation" should be interpreted in a broad sense, for example, it can be a fixed connection or a detachable connection, unless otherwise clearly specified and limited. , or integrated; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection or an indirect connection through an intermediary, it can be the internal communication of two components or the interaction relationship between two components . Those of ordinary skill in the art can understand the specific meanings of the above terms in this application according to specific situations.

In the present application, unless otherwise clearly specified and limited, a first feature being "on" or "under" a second feature may mean that the first and second features are in direct contact, or that the first and second features are indirect through an intermediary. touch. In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The high-efficiency reduced-tar cigarette filter in this application can be used for any cigarette, such as electronic cigarettes, traditional cigarettes, etc., without limitation. The following examples take heat-not-burn cigarettes as an example, but are not limited to This type.

Example 1

As shown in Figure 1, Example 1 of the present application discloses a high-efficiency defocusing filter for cigarettes, which includes: a smoke inlet 1, a smoke outlet 2, an outer casing 3, and a filter tip sleeved inside the outer casing 3. The inner shell 4, the outer shell 3 includes a connected first outer shell and a second outer shell, the cavity between the first outer shell and the inner shell 4 forms a first flue gas passage 5, and the cavity inside the second outer shell The cavity forms a second smoke passage 6, one end of the inner shell 4 is connected to one end of the first outer shell through a connection surface, the smoke inlet 1 is arranged on the connection surface, and communicates with the first smoke passage 5, and the smoke outlet 2 communicates with the second flue gas passage 6, and the side wall of the second outer shell is provided with an air inlet 7; After the second smoke channel 6 is mixed, it finally flows out of the filter tip through the smoke outlet 2 .

By setting the first flue gas passage 5 and the second flue gas passage 6 to be both cavity structures, after the flue gas enters the filter tip, it flows out of the filter tip after passing through the cavity structure, which can ensure a certain amount of smoke while greatly reducing the suction resistance. Concentration, aroma components are retained; the first smoke passage 5 is formed between the first outer casing and the inner casing 4, and the smoke inlet 1 communicates with the first smoke passage 5, so that the smoke flows through the first When a flue gas passage 5 collides with the shell wall, aerosol deposition is generated, thereby greatly reducing harmful substances such as tar in the flue gas; in addition, by opening an air inlet 7 on the side wall of the second outer shell, Fully mixing the flue gas and air in the second flue gas channel 6 can dilute the flue gas and effectively reduce the concentration of carbon monoxide in the flue gas. The air inlet 7 can further reduce the suction resistance and reduce the temperature of the flue gas. The decrease in temperature makes the particulate matter in the flue gas further deposit on the inner wall of the second flue gas passage 6, further reducing the harmful substances in the flue gas.

The draw resistance in this embodiment refers to the draw resistance when the user draws smoke.

Specifically, in this embodiment, the shape of the air inlet 7 is not limited, for example, it may be triangular, quadrilateral, pentagonal, hexagonal, circular or elliptical, as long as the air can enter. Specifically, the shape of the air inlet 7 is elliptical, which is less difficult to form and easy to demould, and can have a high degree of coincidence with the laser drilling position to ensure the air intake, thereby further ensuring the reduction of suction resistance, coke reduction and cooling. .

Specifically, the outer casing 3 is a cylinder adapted to existing cigarettes.

Specifically, this embodiment does not limit the shape of the inner casing 4, as long as the first smoke passage 5 can be formed between the first outer casing and the first outer casing, for example, it can be a cylinder, a prism or a pyramid, etc. In this embodiment, the inner casing 4 is a cylinder.

As an embodiment, the ratio of the distance between the center of the air inlet 7 and the smoke outlet 2 to the length of the outer casing 3 is (0.2-0.6):1. Preferably 0.4:1. By setting the position of the air inlet 7, it is avoided that the air inlet 7 is too close to the smoke section to affect the coke reduction effect, and at the same time, it is prevented that the air inlet 7 is too close to the smoke outlet 2 to reduce the amount of air intake or cannot enter the air, and It leads to excessive suction resistance, poor cooling effect and high content of harmful substances.

Specifically, the length of the outer casing 3 is 3-200mm, preferably 3-30mm, more preferably 14mm, and the distance between the center of the air inlet 7 and the smoke outlet 2 is 0.1-14mm, preferably 5.6mm.

As an embodiment, the ratio of the area of the air inlet 7 to the smoke inlet 1 is (50-650):1, preferably 100-400:1, more preferably 261:1. By controlling the ratio between the air inlet 7 and the smoke inlet 1, and then controlling the ratio between the air entering the mouth and the flue gas, the air can reduce the coke and cool the flue gas, prevent the flue gas from being too high, and at the same time ensure The concentration of smoke and the richness of aroma enhance the user's smoking experience.

Specifically, the area of the air inlet 7 is 4.5-60mm ² , preferably 47.1mm ² , and the area of the smoke inlet 1 is 0.09-1mm ² , preferably 0.18mm ² .

Specifically, this embodiment does not limit the end of the inner casing 4 away from the smoke inlet 1 to be in an open state or a closed state. When it is in an open state, the smoke enters the first smoke channel 5 through the smoke inlet 1, and then, under the action of the suction force, is discharged from the smoke outlet 2 through the second smoke channel 6 and then enters the user's mouth.

As an implementation, this embodiment does not limit the position of the smoke inlet 1, as long as the smoke generated in the smoking section can be led to the filter.

As an embodiment, the end of the inner casing 4 away from the smoke inlet 1 is a closed end, a buffer chamber is formed inside the inner casing 4, and the smoke inlet 1 is arranged at the connection between the first outer casing and the inner casing 4 . By setting the end of the inner shell 4 away from the smoke inlet 1 as a closed end, and the smoke inlet 1 is set at the connection between the first outer shell and the inner shell 4, part of the smoke can be circulated in the buffer chamber before being released. Enter the first flue gas channel 5 through the smoke inlet 1, the setting of the buffer chamber can change the flue gas path, reduce the temperature of the flue gas, avoid excessive flue gas temperature, and at the same time make the particulate matter in the flue gas deposit in the buffer chamber, Increase the effect of reducing focus and reducing damage.

As a preferred embodiment, one end of the inner casing 4 is connected to one end of the first outer casing through a connection surface, and the smoke inlet 1 is arranged at the junction of the connection surface and the inner casing 4 . This setting method increases the opening area of the smoke inlet 1, increases the amount of smoke intake, and at the same time changes the flue gas path so that part of the smoke first enters the buffer chamber and then enters the first flue gas channel 5 through the smoke inlet 1, further improving the drop rate. In addition, the air in the buffer room can also dilute the flue gas and reduce the concentration of carbon monoxide in the flue gas.

Specifically, this embodiment does not limit the number of smoke inlets 1 . Preferably, the number of smoke inlets 1 is two, and the two smoke inlets 1 are symmetrically distributed at the joint between the connection surface and the inner casing 4 .

As an implementation, this embodiment does not limit the shape of the smoke inlet 1 , for example, it can be triangular, quadrangular, circular or elliptical, as long as the smoke can enter the filter through the smoke inlet 1 . Specifically, the smoke inlet 1 is a square with a side length of 0.424mm.

As an embodiment, the ratio of the lengths of the inner casing 4 to the outer casing 3 is (0.3-0.7):1. Preferably 0.5:1. By setting the ratio of the lengths of the inner casing 4 to the outer casing 3, and then coordinating the ratio between the first flue gas passage 5 and the second flue gas passage 6, it is possible to prevent the first flue gas passage 5 from being too short, resulting in poor coke reduction effect , while avoiding that the second flue gas channel 6 is too short to affect the mixing effect between the flue gas and the air, which cannot reduce the drawing resistance.

Specifically, the length of the inner casing 4 is 0.9-13mm, preferably 7mm.

As an embodiment, the ratio of the inner diameter of the outer shell 3 to the width of the first flue gas channel 5 is (3-8):1, preferably 5.39:1. Since the width of the first flue gas channel 5 has an important influence on the tar removal rate, the greater the width, the poorer the effect of the impact of the flue gas on the inner wall of the first flue gas channel 5, so the removal effect of harmful substances is not ideal, and the first flue gas If the width of the gas channel 5 is too small, the impact distance between the flue gas and the first flue gas channel 5 will be shortened, that is, the flow path of the first flue gas channel 5 will be shortened, which will also affect the coke reduction effect. In addition, it will also increase the suction resistance Therefore, in this embodiment, by controlling the width of the first flue gas channel 5, it can not only reduce the suction resistance, but also reduce the tar and other harmful substances in the flue gas to the greatest extent, and improve the tar removal rate.

Specifically, the inner diameter of the outer shell 3 is 3-8 mm, preferably 5.39 mm, the wall thickness of the outer shell 3 is 1 mm, the width of the first flue gas channel 5 is 1 mm, and the wall thickness of the inner shell 4 is 1 mm.

As an embodiment, the ratio of the area of the smoke outlet 2 to the area of the smoke inlet 1 is (55-145):1, preferably (90-130):1, more preferably 126.7:1. By setting the ratio of the area of the smoke inlet 1 to the smoke outlet 2, the amount of smoke in and out can be ensured, and the user's smoking experience can be improved.

Specifically, in this embodiment, the shape and position of the smoke outlet 2 are not limited, as long as the smoke can flow out from the filter tip. For example, the smoke outlet 2 can be arranged at one end of the outer casing 3, or at the side of the outer casing 3. When the smoke outlet 2 is arranged at one end of the outer casing 3, one end can be fully opened or partially opened.

As an implementation manner, the end of the outer casing 3 away from the smoke inlet 1 is fully opened to form the smoke outlet 2 . By setting the end of the outer shell 3 away from the smoke inlet 1 to be fully open, the amount of smoke can be ensured and the user's smoking experience can be improved.

Example 2

Embodiment 2 of the present application provides an electronic cigarette, which includes a connected smoking portion and a filter, the smoking portion is used to generate smoke, and the filter is selected from the filter in Embodiment 1.

Example 3

Embodiment 3 provides a kind of preparation method that is used for the filter tip of cigarette, and this filter tip for cigarette is the filter tip in embodiment 1, and this method comprises the following steps:

(1) The raw material is melted, and the raw material includes 42 parts of styrene-ethylene-butadiene-styrene block copolymer, 22.5 parts of polypropylene, 35 parts of paraffin oil and 0.5 part of tetrakis[β-(3,5-di-tert-butyl Base-4-hydroxyphenyl) propionate] pentaerythritol ester;

(2) Injection molding, using injection molding equipment to inject molten raw materials into the mold, cooling and molding after pressure maintaining, to obtain cigarette filters,

Among them, the mold temperature is 25°C, the feeding temperature of the barrel in the injection molding equipment is 170°C, the temperature of the front section is 180°C, the temperature of the back section is 190°C, the temperature of the nozzle is 210°C, the injection pressure is 3MPa, and the holding pressure 1.8MPa, the back pressure is 0.7MPa, and the cooling time does not exceed 10s.

Prepare respectively filter tip 1#-7# and filter tip D1#-D3# according to the above method, the wall thickness of filter tip 1#-7# and filter tip D1#-D3#'s inner casing 4 and outer casing 3 is 1mm, all the other parameters As shown in Table 1:

Table 1

In addition, the raw materials of the filter were changed to obtain the filter D4#-D6# respectively, wherein the raw material of D4# included 64.5 parts of styrene-ethylene-butadiene-styrene block copolymer, 35 parts of paraffin oil and 0.5 part of four [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester, all the other conditions are the same as filter tip 1#;

The raw materials of D5# include 42 parts of styrene-ethylene-butadiene-styrene block copolymer, 22.5 parts of polypropylene and 0.5 parts of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) Propionic acid] pentaerythritol ester, all the other conditions are identical with filter tip 1#;

The raw materials of D6# include 42 parts of polystyrene, 22.5 parts of polypropylene, 35 parts of paraffin oil and 0.5 part of tetrakis [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, the rest The conditions are the same as filter 1#.

Experimental example

The flue gas temperature, coke reduction efficiency, CO reduction efficiency and suction resistance of filter 1#-7#, D1#-D3# in Example 3 were tested respectively. The test method is as follows, and the test results are shown in Table 2 :

Smoke outlet 2 flue gas temperature: the outlet temperature is measured by inserting a thermocouple.

Coke reduction efficiency: Take the cigarette with the traditional general-purpose cellulose acetate filter as sample 1, and the cigarette with the filter in Example 3 as sample 2, use the existing rotary smoking machine to test sample 1 and sample 2 respectively Carry out suction and test the amount of tar, coke reduction efficiency = (amount of tar in sample 2-amount of tar in sample 1)/amount of tar in sample 1.

CO reduction efficiency: take the cigarette with the traditional general-purpose acetate filter as sample 1, and the cigarette with the filter in Example 3 as sample 2, and use the existing rotary smoking machine to test sample 1 and sample 2 respectively. Perform suction and test the CO content, CO reduction efficiency = (CO amount of sample 2 - CO amount of sample 1)/CO amount of sample 1.

Draw resistance: tested by traditional cigarette comprehensive test bench.

Table 2

It can be seen from Table 2 that the filter tip prepared by the method of the present application has moderate flue gas temperature, is suitable for smoking, and has high coke reduction efficiency and CO reduction efficiency, greatly reducing harmful substances in the flue gas; The suction experience is good.

In addition, filter 1#-7# and filter D1#-D3# have stable performance and stable pore size during processing, and will not produce peculiar smell during the suction process, and will not deform after suction; while filter D4#- During the processing of D5#, the pore diameter is unstable, the processing performance is poor, and there is odor during the suction process, the suction experience is poor, and deformation occurs after suction, indicating that its temperature resistance is poor.

Each embodiment in this specification is described in a progressive manner, the same and similar parts of each embodiment can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and for relevant parts, refer to part of the description of the method embodiment.

The above descriptions are only examples of the present application, and are not intended to limit the present application. For those skilled in the art, various modifications and changes may occur in this application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims (10)

1. A high-efficiency tar-reducing filter for cigarettes, characterized in that it comprises: a smoke inlet, a smoke outlet, an outer shell and an inner shell sleeved inside the outer shell, the outer shell includes a connected second An outer shell and a second outer shell, the cavity between the first outer shell and the inner shell forms a first smoke channel, and the cavity inside the second outer shell forms a second smoke channel, One end of the inner shell is connected to one end of the first outer shell through a connection surface, the smoke inlet is arranged on the connection surface and communicates with the first smoke passage, and the smoke outlet In communication with the second flue gas channel, an air inlet is opened on the side wall of the second outer casing;

   The smoke passes through the smoke inlet and the first smoke channel in sequence, and after being mixed with the air flowing in from the air inlet in the second smoke channel, finally flows out of the filter through the smoke outlet.
2. The filter for cigarettes according to claim 1, characterized in that the ratio of the distance between the center of the air inlet and the smoke outlet to the length of the outer casing is (0.2-0.6): 1, Preferably 0.4:1.
3. The filter for cigarettes according to claim 1, characterized in that the ratio of the area of the air inlet to the smoke inlet is (50-650):1, preferably (100-400):1; and / or

   The ratio of the area of the smoke outlet to the area of the smoke inlet is (55-145):1, preferably 126.7:1.
4. The filter tip for cigarettes according to any one of claims 1-3, characterized in that, the end of the inner casing away from the smoke inlet is a closed end, and a buffer chamber is formed inside the inner casing, and the The smoke inlet is arranged at the connection between the connection surface and the inner casing.
5. The filter tip for cigarettes according to claim 6, characterized in that the ratio of the lengths of the inner shell to the outer shell is (0.3-0.7):1, preferably 0.5:1.
6. The filter tip for cigarettes according to any one of claims 1-3, characterized in that the ratio of the inner diameter of the outer casing to the width of the first smoke channel is (3-8):1, preferably 5.39:1.
7. A composite material for preparing the cigarette filter according to any one of claims 1-6, characterized in that it comprises: 30-50 parts of styrenic block copolymer, 15-30 parts of polypropylene, 30-40 parts of mineral oil and 0.2-0.7 parts of antioxidant;

   Preferably, the composite material includes 42 parts of styrene-ethylene-butadiene-styrene block copolymer, 22.5 parts of polypropylene, 35 parts of paraffin oil and tetrakis[β-(3,5-di-tert-butyl- 0.5 part of 4-hydroxyphenyl) propionate] pentaerythritol ester.
8. A method for preparing a filter for cigarettes, characterized in that it comprises the following steps:

   (1) raw material melting, described raw material is the composite material described in claim 7;

   (2) Injection molding: using injection molding equipment to inject molten raw materials into a mold, and cooling and molding after maintaining pressure to obtain the cigarette filter, wherein the barrel temperature of the injection molding equipment is divided into at least two stages.
9. The preparation method according to claim 8, characterized in that, the feeding temperature of the barrel in the injection molding equipment is 160-180°C, the temperature in the front section is 170-190°C, the temperature in the back section is 180-195°C, and the injection A mouth temperature of 200-220°C; and/or

   The injection pressure of the injection molding equipment is 1.5-4.5 MPa, the holding pressure is 50-70% of the injection pressure, and the back pressure is 0.3-1.1 MPa; and/or

   The cooling time is not more than 10s.
10. A cigarette, characterized in that it comprises a connected smoking part and a filter, the smoking part is used to generate smoke, and the filter is selected from the filter described in any one of claims 1-6.

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