TW200301681A - Smoking filter and smoking article - Google Patents

Abstract

A smoking filter contains a hydrotalcite compound exhibiting a lamellar structure in which a large number of octahedral layers of a metal hydroxide are laminated one upon the other. The smoking filter permits selectively removing formaldehyde contained in mainstream smoke.

Description

200301681 V. Description of the invention (1) [Technical field to which the invention belongs] ^ The present invention relates to a cigarette filter and a cigarette having a filter. [Prior art] The mainstream smoke inhaled by smokers during smoking contains various chemical constituents. Among these chemical components, the lower carbon aldehydes represented by acetaldehyde are difficult to remove by adsorption on ordinary cigarette filters. Naturally, the desire is to remove the aldehydes of this mainstream smoke. _ It is customary to use an activated carbon filter as an adsorbent for removing mainstream formaldehyde. In addition, it is desirable to use various other adsorbents. ® However, the adsorbents used in the past may also adsorb components other than formaldehyde, which may have a negative effect on the flavor and taste of cigarettes. An object of the present invention is to provide a cigarette filter and a cigarette having a filter which can selectively remove the formaldehyde contained in mainstream cigarettes. [Summary of the Invention] The cigarette filter of the present invention includes a hydrotalcite compound having a sheet-like structure in which a large amount of metal hydroxide octahedral layers are stacked on each other. x The hydrotalcite compound used in the present invention is represented by the following formula: • M2 + 1_, M3 + x (0H) 2 (An-) x / n · mH20 ^ where M 2+ represents a group selected from magnesium ions, zinc ions, A group of divalent metal ions consisting of nickel ions and calcium ions, where M 3+ represents an aluminum ion, and A η represents an anion having a valence of η. The anion is selected from the group consisting of C03, S04, 00C-C00, CBr, F , No3, Fe (CN) 63, Fe (CN) 64, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, enoic acid and its derivatives, apple

314312.ptd Page 4 200301681 V. Description of the invention (2) Acid, salicylic acid, acrylic acid, adipic acid, succinic acid, citric acid and acetic acid, 0.1 < X < 0 · 4, and 0 < m < 2. The cigarette filter of the present invention is prepared by dispersing a hydrotalcite compound having an average particle size between 200 microns and 800 microns in, for example, a fiber bundle (f i be r t ow) or a non-woven fabric. Typical fibers used in the present invention consist of cellulose acetate. The cigarette filter of the present invention can be prepared by forming and adding a hydrotalcite compound having an average particle size of not more than 10 microns to a paper sheet. The cigarette filter of the present invention may include a plurality of filter segments, and at least one of the filter segments contains an aqueous talc compound. In this example, in addition to the filter section containing the hydrotalcite compound, a charcoal filter section may be used. The cigarette filter of the present invention may include a plurality of filter segments and hydrotalcite particles filling a space between adjacent filter segments. Furthermore, the cigarette having a filter according to the present invention includes the cigarette filter described above and a stem (t 0 b a c c 0 b a r) connected to the cigarette filter. As a result of intensive research on various viewpoints aimed at finding an adsorbent that can effectively reduce the mainstream formaldehyde content, the inventors found that the hydrotalcite compound can effectively remove the formaldehyde. The hydrotalcite compound has a flaky structure in which a large number of divalent or trivalent metal hydroxide octahedral layers are stacked on each other, and anions are embedded in the octahedral layer. The octahedral layer acts as a host and has a salinity. It is a matter of course that the host's salinity distribution and the ion exchange of the embedded anion will cause the hydrotalcite compound to remove formaldehyde. In the present invention, natural or synthetic hydrotalcite compounds can be used. The

314312.ptd Page 5 200301681 V. Description of the invention (3) 豢 Hydrotalcite compounds are represented by the following formula:-M2, _XM3 + X (〇H) 2 (An-) x / n · mH20. In the most common hydrotalcite compounds, magnesium ions constitute the divalent metal ion M2 + contained in the above formula, aluminum ions constitute the trivalent metal ion M3 +, and C0 32— or SO42 is converted into the anion An ~. In addition to magnesium ions, zinc ions, nickel ions, ions, or calcium ions can also constitute the divalent metal ion M 2+. Similarly, in addition to C0 32- or S04 2-, the anion can also be selected from 00C-COO, CBr, F, 'N03, Fe (CN) 63-, Fe (CN) 64, benzene di Osmic acid, isophthalic acid, terephthalic acid, maleic acid, enoic acid and its derivatives, malic acid, salicylate Θ, acrylic acid, adipic acid, succinic acid, citric acid and sulfonic acid Group of people. The symbol X in the general formula is greater than 0.1 but less than 0.4, that is, 0.1 < X < 0.4, and the symbol m is greater than 0 but less than 2, that is, 0 < m < 2. The magnesium-aluminum-based hydrotalcite compound is stable when the X value is between 0.20 and 0.33. In order to manufacture the hydrotalcite, basic carbonate or basic carbonate and caustic alkali are added to an aqueous solution containing a water-soluble salt or acid and a water-soluble ballast. The water-soluble aluminum salt is selected from aluminum sulfate, aluminum acetate, and sulfuric acid. 0 or higher。 The group of aluminum and potassium, while maintaining the pH of the reaction mixture at 8.0 or higher. φ can control the size of the micropores of the hydrotalcite compound by, for example, the size of the anion embedded in the hydrotalcite compound. The hydrotalcite compound may also perform various functions, depending on the nature of the anion and the state of the interlayer water. Regarding cigarette filters with hydrotalcite compounds, various types are conceivable as follows: (1) Cigarette filters, wherein the hydrotalcite compound is dispersed in cellulose acetate

3143] 2.ptd page 6 200301681 V. Description of the invention (4) In fiber bundles or non-woven fabrics made of vitamins. (2) A cigarette filter is made by forming a paper sheet to which a hydrotalcite compound is added. (3) Cigarette filters are composed of at least two sections, which include at least one section consisting of the cigarette filter represented by item (1) or (2) above, and another section consisting of a conventional cellulose acetate filter or Composed of charcoal filter. (4) A cigarette filter is made by filling the gap in the stuffer-gap-stuffer structure with the hydrotalcite compound. In this example, the stuffing material is selected from a conventional cellulose acetate filter or a charcoal filter, or the filter shown in the above item (1) or (2). Similarly, if there are two or more voids, the hydrotalcite compound may fill at least one void and charcoal to fill another void. It is desired to control the particle size of the hydrotalcite compound as follows. When a hydrotalcite compound is used to disperse a cigarette filter in a cellulose acetate bundle or a non-woven cloth, or when a hydrotalcite compound is a cigarette filter or a filter filled in the gap between the stuffer-void-filler, The hydrotalcite compound has a particle size of 200 to 800 micrometers, and more desirably 400 to 600 micrometers. On the other hand, in the case of a cigarette filter formed using a paper sheet formed by adding a hydrotalcite compound, it is desired that the hydrotalcite compound has a particle size of not more than 10 m. [Embodiment] Example 1 uses a hydrotalcite compound represented by M g 6A 1 2 (0 Η)! 6C 0 3 · 4 Η 20 kg. The particle size of the hydrotalcite compound is controlled to be from 250 to 500 microns by pulverization and sieving. The filter 1 shown in FIG. 1 is prepared using the hydrotalcite compound. more

314312.ptd Page 7 200301681 V. Description of the invention (5) Specifically, the hydrotalcite compound powder 3 is filled into the space between the diacetate filter segments 2, 2 respectively wrapped with the stuffing cigarette paper, and then formed into a shape The paper 4 wraps the final structure. The filter of the filler-void-filler structure is prepared 1 ° λ For comparison, the filler-void-filler structure shown in Figure 1 is prepared using the following adsorbent: Charcoal, charcoal with high specific surface area, charcoal impregnated with alkali metal salts, charcoal impregnated with amine, activated alumina, magnesia, alumina, magnesium silicate, zinc oxide, silica gel, zeolite, for formalin Structural material aggregates, column materials for gas chromatography (GC), and water-absorbent resins. These filters are made with the same amount of adsorbent. Similarly, a test cigarette was prepared by connecting a tobacco segment containing 12 mg of tar and each filter. The formaldehyde content of mainstream cigarettes is measured according to the "Official Canadian Health Standards Method" (2, 4-DNPH-HPLC method) to provide the removal rate of formaldehyde. More specifically, 9.51 g of 2,4-dinitrophenylhydrazine (DNPH) was dissolved in 1 liter of acetonitrile, and then 5.6 ml of 60% perchloric acid was added to the solution, Ultra-pure water was then added to the solution to prepare a 2 liter trapping solution. g The structure of the measuring device will now be described with reference to FIG. 2. As shown in the figure, the DNPH trap liquid 12 is placed in a Drechsel trap 1 1. The Joel type trap 11 has an internal volume of 100 ml, and the amount of the DNP (R) trap liquid 12 is 80 ml. The trap 11 was cooled in an ice-water bath 1 3. The lower end of the glass tube 14 connected to the cigarette 10 is immersed in the trap liquid 12 of the trap 11. Furthermore, the Cambridge

314312.ptd Page 8 200301681 V. Description of the invention (6) pad) 16 The glass tube 15 is connected to the trap 17 and the cambridge 17. The closed space communicates, and the cigarette 10 is connected to the glass tube 4 at T. Under quasi-smoke conditions, the cigarette is automatically smoked. The standard sigh specified in the 80 standard is more clear. The action of a main cigarette inhaling 35 ml of smoke within 2 seconds is repeated every "second. When the mainstream When the smoke produces foam, the formaldehyde will be converted into a derivative of Μρ 。. Two cigarettes are measured. In this example, the use of different, L ^ ^,. J, and the attached cigarettes are controlled to have the same pressure loss. By high efficiency The resulting osmic acid derivative was measured by liquid chromatography (HPLC). In the first step, the trap solution was filtered, and then the filtered trap solution (4¾ liters of trap solution) was diluted with a Trizma alkaline solution. : 6 ml of Chuanma test solution). Then 'diluted solution was measured by Η PLC. The measurement conditions of this η plc are as follows: Column: HP LiChrospher 100RP-18 (5 ") 250 x 4 mm protective tube column Temperature detection wavelength injection volume:

HP LiChrospher 100RP-18 (5 //) 4x 4mm 3 0 ° C DAD 3 5 6nm 20ml mobile phase: gradient of 3 phases (solution A: containing 30% acetonitrile, 10% Tetrahydrofuran and 1% isopropyl alcohol in an ultra-pure aqueous solution; Solution B: Ultra-pure aqueous solution containing 65% acetonitrile, 1% tetrahydrofuran, and 1 ° / ◦ isopropanol; Solution C: 100% acetonitrile) . The movement rate of osmic acid is expressed as follows:

E two (W-W,) / W

314312.ptd Page 9 20031681 V. Description of the invention (7) where E represents the rate of movement of formaldehyde, W represents the measured formaldehyde content when using a cigarette without adsorbent, and W 'means the use of adsorbent The formaldehyde content was measured in the case of cigarettes. Figure 3 shows the removal rate of formaldehyde when various adsorbents are used. As shown in Figure 3, the use of hydrotalcite as an adsorbent can remove the formaldehyde most effectively. Example 2 'Using a hydrotalcite compound or charcoal, which is most commonly used as an adsorbent in cigarettes, as the adsorbent, the removal rate of the vapor phase components contained in mainstream cigarettes was measured. By preparing a particle size of 2 50 to 50 A 0 μm hydrotalcite compound or charcoal was used as the adsorbent and 50 mg of the adsorbent was loaded. A filter similar to that shown in FIG. 1 was manufactured as in Example 1. Then, a tobacco segment containing 12 mg of tar was connected to a filter thus manufactured to prepare a cigarette. The method for measuring the removal rate of the vapor phase components of mainstream cigarettes will be described below with reference to FIGS. 4 and 5. FIG. 4 shows a method for capturing the vapor phase composition. As shown in the figure, the cigarette 10 is connected to the smoking machine 17 so that the cigarette 10 automatically smokes under the standard smoking conditions prescribed by the ISO standard. In this example, the particulate phase of the mainstream smoke is removed by a Cambridge filter, and the vapor phase is captured by an airbag 20. In the same way, the action of a cigarette sucking 35 milliliter of smoke within 2 seconds is repeated every 58 seconds. Furthermore, 10 cigarettes were processed automatically (treated at 22 ° C and 60% humidity). Figure 5 shows a gas chromatograph. As shown in the figure, the airbag 20

314312.ptd Page 10 200301681 V. Description of the invention (8) The pre-determined amount of vapor phase composition captured is stored in sample circle 21. After the standard gas is injected, the vapor phase composition is injected into the gas chromatograph 22. The components are separated in a column (DB-WAX) and detected by a detector. In addition, the amount of this component is analyzed by a program installed in the personal computer 23. The analytical value was obtained by dividing each vapor phase composition by the peak area of the standard gas. The removal rate E of each vapor phase component is expressed as follows:

E = (AA,) / A where E represents the removal rate of each vapor phase composition, A represents the analytical value of the composition measured with an adsorbent-free cigarette, and A 'represents the composition contains an adsorbent Analytical value measured for cigarettes. Fig. 6 is a graph showing the relationship between the vapor pressure of the vapor phase composition and the removal rate of the composition. As shown in Fig. 6, the removal rate increases as the vapor pressure of the vapor phase composition increases in the case of using charcoal as an absorbent. On the other hand, in the case where a hydrotalcite compound is used as the adsorbent, the description of the removal rate of formaldehyde is particularly high, and support for the fact that the hydrotalcite compound can selectively remove the formaldehyde. Example 3 For example, in the case of using a hydrotalcite compound in a cigarette filter constructed as shown in Fig. 1, the size of the hydrotalcite compound must be appropriately controlled to control the attraction and outflow resistance to tar / nicotine. If the hydrotalcite compound is finely granular, samples having different particle size distributions can be prepared. In this example, the samples are classified according to the average particle size of the hydrotalcite compound. Figure 7A shows three samples with average particle sizes of 250 microns, 500 microns, and 800 microns.

314312.ptd Page 11 200301681 V. Description of the invention (9) The filter as shown in Figure 1 is prepared using hydrotalcite particles with different average particle sizes. These filters are different from the amount of hydrotalcite compounds filled in each other. For reference comparison, the filter of the structure shown in Figure 1 was also prepared using charcoal. These filters are also different from the amount of charcoal filled in each other. The resistance of these filters to suction was detected at a suction flow rate of 1050 ml / min. In this paper, the impedance to the suction is calculated by excluding the suction impedance caused by the diacetate filter segments 2, 2 shown in Fig. 1. Figure 7B is a graph showing the relationship between the average particle diameter and the attraction resistance. As shown in Figure 7B, the use of adsorbent particles with an average particle diameter of 250 microns: the absorption impedance is high in the example, and the absorption impedance in the case of using adsorbent particles with an average particle size of 800 microns Department of low. Figure 7B also reveals that ideally designed hydrotalcite particles with an average particle size between 400 and 600 microns are used in cigarettes. Stoneman's Hardness In the case of using fine-grained granules, hydrotalcite granules of a desired size can be prepared by any granulation method such as roll granulation, thermoforming, coating and cutting, or extrusion molding. It should be noted that under this connection, in order to prevent the hydrotalcite particles from being broken during the process of the filter, it is advisable to use a granulation method capable of producing fine granular hydrotalcite particles of appropriate hardness. The inventors have found that if the hydrotalcite has a degree between 300 g / mm2 and 3,000 g / mm2, the hydrotalcite particles can be prevented from breaking during the process of the filter. Example 4 This example is intended to support the rate at which the hydrotalcite particles can reduce the acetaldehyde content in mainstream smoke, depending on the surface area of the hydrotalcite particles.

314312.ptd Page 12 200301681 V. Description of the invention (10) Various fine-grained hydrotalcite particles are prepared by the following methods: (A) press granulation, (B) hot-press molding, and (C) extrusion molding. The average surface area per unit weight of hydrotalcite particles was calculated using a laser scattering type particle size distribution measuring device. The filter shown in Fig. 1 is prepared using hydrotalcite particles having various surface areas. In this example, the total surface area of the hydrotalcite particles is adjusted by controlling the amount of the hydrotalcite particles. Next, the relationship between the total surface area of the hydrotalcite particles and the rate of reduction of the formaldehyde content in the mainstream smoke was examined. Figure 8 is a diagram showing the results. It is obvious from Fig. 8 that the reduction rate of the formaldehyde content in the mainstream smoke will increase as the total surface area of the hydrotalcite particles increases. This tendency has nothing to do with the method of granulating the hydrotalcite particles. Example 5 This example is intended to detect the reduction rate of acetaldehyde contained in mainstream smoke, which is achieved by a paper filter with hydrotalcite particles, and by a cellulose acetate filter with fine granular hydrotalcite particles. Specifically, hydrotalcite particles having an average particle size of not more than 10 micrometers were added at the same time when manufacturing the paper sheet. Next, using the obtained paper sheet, a paper filter 7 shown in Fig. 9 was prepared. For comparison, a paper sheet without hydrotalcite particles was formed to prepare a filter. The filter can also be prepared by dispersing fine granular hydrotalcite particles in the cellulose acetate bundle. For comparison, cellulose acetate filters do not require the use of hydrotalcite particles. Incidentally, the filter thus prepared is 25 mm long and made as much as possible

314312.ptd Page 13 ώυ ^ ουιυοχ V. Description of the invention (11) It is necessary to change the attraction resistance to detect radon in mainstream smoke. The results show that the ratio shown in Table 1 is lower when the ratio of water outflow is included. And the average particle size is not large. The filter of the coke filter on the surface of the oil filter and the filter surface of the oil filter are ready to touch the paper | > The amount should be connected to this because it is widely used by ts to disperse and widely use U aldehydes. The rate f device is Shishi 4 / speed f filter fruit slip low U paper water condensation h. Of it. h grains of rice, even amount of 1 y when the micro package ο both contain Table i, Shisuo 1 obtained aldehyde in 5i sliding

Hydrotalcite dosage (mg)

Tar outflow (Taiwan coupons)

Example 6: This article discusses that the rate of reduction of the organic vapor composition can be improved by using a water filter and a charcoal filter. -M r kg: contains acetate filter section, hydrotalcite (ητ) filter section, and 丄 from Mi Mi to 4 ι 1 1 1, 1 1 1 1. The acetate filter segment was prepared by < πτπ π system t and had a length of 7 mm. The hydrotalcite was pumped with a lambda to make a supply of ^ 有 耄 耄 水 hydrotalcite particles of cellulose acetate bundles are bundled into a bundle and long sound & ancient group Shi Luo Ba Yao ancient w length is 10 pens . In addition, the charcoal filter section is formed by bundling cellulose acetate bundles with a sound of 7 0¾ 杳 for the moon ..

314312.ptd Page 14 200301681 V. Description of the invention (12) Preparation and length is 10 mm. FIG. 10 shows the structure of the filters I I I shown in Table 2. As shown in the figure, the charcoal filter section 5 is placed on the cut tobacco side, the acetate filter section is placed on the suction side, and the HT filter section 6 is placed on the charcoal filter section 5 and the acetate filter section. Between 2. The rate of decrease of the total organic vapor of mainstream smoke (the total orgaiu vaporTOV) and the rate of reduction of formaldehyde are measured using these filters. The results are shown in Table 2. As shown in Table 2, the function of the charcoal filter enables the filter II to reduce the total amount of organic vapors, and the function of the hydrotalcite (HT) filter enables the filter I I I to reduce the formaldehyde content. Table 2 Tobacco side center suction 17 Allowed side τον Low rate of decrease (° / 〇) Decrease rate of formaldehyde (%) I Charcoal container Acetate filter Acetate filter Acetate filter 62.7 67.2 II Acetate filter Hydrotalcite filter Acetate Filter 20.8 69.3 III Charcoal filter Hydrotalcite filter, Acetate filter 64.8 71.9 Weight of additive: 70 mg / 10 mm Filter length: 10 mm, 10 mm and 7 mm Filter top flow resistance: 72 mmWG / 2 7 mm vents: Various modifications related to the present invention that are unthinkable are listed below. For example, in a filter having the structure shown in Fig. 1, another filter may be used.

314312.ptd Page 15 200301681 V. Description of the invention Paragraph (13) replaces at least one acetate filter segment 2. Specifically, a hydrotalcite filter section or a charcoal filter section may be used instead of at least one acetic acid filter section 2. In the example of using the charcoal filter section, it is desirable to set the charcoal filter section on the grass side as cut in Fig. 10. In the structure shown in Fig. 10, cellulose acetate bundles having dispersed hydrotalcite are used to form the hydrotalcite filter section. Alternatively, a hydrotalcite filter section can be prepared by forming a paper sheet made by adding a hydrotalcite compound. It is also possible to make a four-stage structure filter by connecting the additional filter section to the three-stage structure filter shown in Fig. 10. • Furthermore, a filter including a charcoal filter section 5, a gap filled with hydrotalcite particles 3, a hydrotalcite (HT) filter section 6 and an acetate filter section 2 can be used, as shown in Fig. 11. In this example, the hydrotalcite filter section 6 may be mainly an acetate filter or a paper filter. The interstices of the filled HT particles 3 and the HT filter section 6 can be set relative to each other, as shown in FIG. 11. In Fig. 11, the voids are filled with HT particles. Alternatively, the void can be filled with charcoal particles. Industrial Applicability According to the present invention, a cigarette filter and a cigarette having the filter can be provided.

314312.ptd Page 16 200301681 Brief description of drawings [Description of drawing fs] Sheet 1 is a perspective view showing a filter manufactured in an embodiment of the present invention. Fig. 2 shows the structure of a device used in the embodiment of the present invention for measuring formaldehyde contained in mainstream cigarettes. FIG. 4 shows a method for collecting vapor phase components from mainstream cigarettes. The method is used in the embodiment of the present invention. FIG. 5 shows gas chromatography of the vapor phase components contained in mainstream cigarettes. The gas chromatography system is used in the embodiment of the present invention; FIG. 6 shows the relationship between the vapor pressure of the vapor phase composition and the removal rate of the vapor phase composition, which are suitable for hydrotalcite or charcoal as an absorbent Figure 7A shows the particle size distribution of the hydrotalcite particles; Figure 7B shows the relationship between the average particle size of the hydrotalcite particles and the attraction resistance; Figure 8 shows the relationship between the hydrotalcite particles The relationship between the surface area and the reduction rate of the formaldehyde; Figure 9 is a perspective view showing the structure of the paper filter made in Example 5; Figure 10 is a view showing the structure of the three-stage filter made in Example 6. Perspective view; Figure 11 is a perspective view showing a filter structure according to another embodiment of the present invention. 1 filter 2 acetate filter

314312.pid Page 17 200301681

Brief description of the drawing 3 Hydrotalcite compound powder 4 Shaped paper 5 Mushan anaerobic filter section 6 Hydrotalcite filter section 7 Paper filter 10 Cigarette 11 Drechse 1 trap 12 DNPH trap liquid 13 Ice water bath 14 Glass Tube 15 Glass tube 16 Cambridge pad 17 Smoker 20 Air bag 21 Sample ring 22 Gas chromatograph 2 Personal computer 314312.ptd Page 18

Claims (1)

200301681 6. Scope of patent application 1. A cigarette filter comprising a hydrotalcite compound having a sheet-like structure in which a large number of metal hydroxide octahedral layers are stacked on each other. 2. The cigarette filter according to item 1 of the scope of patent application, characterized in that the hydrotalcite compound is represented by the following formula: Μ2 + 1.χΜ3 + χ (0Η) 2 (Αη-) χ / η · mH20 where Μ21 represents Divalent metal ions selected from the group consisting of magnesium ions, zinc ions, nickel ions, and calcium ions, M 3+ represents an aluminum ion, and A η_ represents an anion having a valence of η, and the anion is selected from C03, S04, 00C-C00, C, Br, F, No. 3, Fe (CN) 63-, Fe (CN) 64-, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, olefin Acids and their derivatives, malic acid, salicylic acid, acrylic acid, adipic acid, succinic acid, citric acid and sulfonic acid, 0.1 < χ < 0.4, and 0 < m < 2. 3. The cigarette filter according to item 1 of the patent application, which is characterized in that the hydrotalcite compound having an average particle size between 200 microns and 800 microns is dispersed in a fiber bundle or a non-woven fabric. 4. The cigarette filter of claim 3, characterized in that the fiber is made of cellulose acetate. 5. The cigarette filter according to item 1 of the scope of patent application, characterized in that the filter is made by forming a paper sheet with a hydrotalcite compound having an average particle size of not more than 10 microns. 6. The cigarette filter according to item 1 of the patent application scope, comprising a plurality of filter segments, at least one of which contains a hydrotalcite compound. 7. The cigarette filter as claimed in item 6 of the patent application, characterized in that 314312.pid Page 19 200301681 6. Scope of patent application In addition to the filter section of the hydrotalcite compound, it also includes the charcoal filter section. 8. The cigarette filter according to item 1 of the patent application, which is characterized by including a plurality of filter segments and filling hydrotalcite particles into the space between adjacent filter segments. 9. A cigarette with a filter comprising the cigarette filter according to any one of claims 1 to 8 of the patent application scope and a tobacco rod connected to the cigarette filter. 3143] 2.ptd Page 20