JPH03206876A - Cigarette - Google Patents

Abstract

PURPOSE: To obtain a cigarette which is formed by mounting a filter of the filtration efficiency increasing with smoking at a tobacco rod of the strength decreasing from its ignition end toward its opposite end and is improved in the uniformity relating to the smoke flavor and arom during smoking. CONSTITUTION: The segment region of the tobacco rod of this cigarette is formed to a segment shape. Tobacco leaves stronger than those at the other one end side 2 from which smoke is discharged are housed at the ignition end side 1. A filter rod consists of a plug sheath 6, a fibrous material 4 and a tubular body 5 arranged in the longitudinal direction of the filter 3. The one end of this tubular body 5 is closed by gathering pleats 8 and the other end is formed with an open end 9. The wall of the tubular body 5 near the closed end is provided with a pair of opposite holes 7. When a person smokes the cigarette mounted with the filter 3, the smoke enters the inside of the filter rod and moves in the inner side of the fibrous filter material before the smoke arrives at the position of the holes 7. The smoke in this part flows partly to the holes 7 and is partly sufficiently filtered by the fibrous filter material and is discharged. The filtration efficiency particularly in the radial direction increases as the smoking progresses.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to cigarettes with improved uniformity of smoke, flavor and aroma intensity during smoking.

[Prior Art] When a regular cigar or cigarette filled with tobacco leaves of uniform quality is smoked, nicotine and other smoke components generated in the initial stage are partially condensed on the unburned tobacco leaves. However, it is known that these substances are then released together with combustion products in the later stages of smoking, so that as smoking continues, the taste becomes stronger and the amount of nicotine released increases.

It has already been proposed to use tobacco leaves of different quality in separate areas within the tobacco rod, thereby making the strength and flavor uniform from plate to plate.

British Patent No. 8,577 proposes a tobacco rod in which separated areas are filled with different types of tobacco leaves.

British Patent No. 250,063 fills a region of gradually decreasing cross-sectional area from the lighting end of the rod to the other end where the smoke exits with a strong tobacco blend, and fills the remaining region with a mild tobacco blend. It teaches filling tobacco compositions, ie, using strong tobacco leaves in a cone shape.

British Patent No. 1,340.100 uses natural tobacco leaves in the first smoking part and reconstituted tobacco leaves or a tobacco substitute in the second smoking part to form both parts into a wedge shape. Alternatively, the first smoking area is taught to have a conical or truncated conical shape.

British Patent No. 1,343,402 uses shredded carbon-filled paper to replace part of the tobacco leaf, so that the amount of smoke produced is more uniform when smoking cigarettes. It is proposed to increase the amount towards the suction side of the cigarette smoker.

U.S. Pat. No. 4,759,380 describes a cigarette in which the tobacco rod is comprised of two regions filled with different types of tobacco leaves, and a filter is attached to the second region,
The second region in this case may include reconstituted tobacco leaves, expanded tobacco leaves, treated tobacco petioles, or blends thereof.

The idea of varying the tobacco composition along the length of the smoke tS rod can be used in colored soils to make the amount of smoke emitted more uniform from garment to garment, but the tobacco leaves in the final stage can be repeatedly smoked. Because of the exposure, the last few doses are often more stimulating than the previous ones.

For regular cigarettes tied with tobacco leaves of uniform quality - another way to make the smoking experience more uniform from garment to garment is to use special filters that increase the filtration efficiency during the smoking process.

Examples of such specialized filters are: GB 2,102,271-A; GB 2,103,065-A; GB 2,105.566-A; GB 2,119; No. 225-A. These filters employ two flow paths: a flow path with low filtration efficiency and low pressure loss, and a flow path with high filtration efficiency and large pressure loss. At the initial stage of smoking, smoke passes through channels with low pressure drop or due to the blocking effect of tar deposition, and in subsequent smoking, the smoke channel is switched to channels with high pressure drop.

Other examples can be found in the following literature:

U.S. Patent No. 4,460,000 U.S. Patent No. 4,469,112 European Patent Application No. 88308323.0 (Publication No. 310,257) European Patent Application No. 89310421.6 (Publication No. 364.253) European Patent Application No. 89310430.7 (Publication No. 364,256) The filters described in these documents pass smoke through an orifice consisting of an impermeable or low permeable desk or tube provided within the filter. Filtration efficiency is increased by depositing tar on the fibrous filtration media when the flow becomes narrow.

PCT Patent Application No. CA/90100070 uses a fine fiber fabric to provide variable filtration efficiency.

This high filtration efficiency, low pressure drop fabric forms a mantle of low pressure drop and low filtration efficiency tow core wrapped in a high pressure drop and high filtration efficiency tow tubular body. The core is then sealed at the end closest to the cigarette, allowing smoke to pass through the outer tubular body or cylindrical textile mantle and into the core section. Deposition of tar into fine fibers results in a gradual increase in filtration efficiency during the smoking process. Another feature of this filter is that high filtration efficiency can be obtained even during the initial period of smoking when the pressure drop of the filter is relatively low.

All of these conventional techniques increase pressure loss during the smoking process,
Moreover, tip ventilation (ttp ve
During smoking of the cigarette, the level of tip ventilation effective to emit smoke evenly increases with each edition.

These specialized filters are particularly effective in minimizing the increase in smoke production in the last two puffs.

DESCRIPTION OF THE INVENTION The present invention provides a cigar or cigarette comprising a tobacco rod whose strength decreases from the lighting end of the tobacco rod to its opposite end, and a filter whose filtration efficiency increases as the tobacco rod is smoked.

Preferably, the tobacco rod comprises two or more areas filled with two or more different types of tobacco leaves or a blend thereof, and the cigarettes filled at the lighting end of the rod are the same as the cigarettes filled at the smoke discharge end. It has a higher level of strength, quality, flavor and nicotine content.

The demarcated area may take the form of a segment, and the strong tobacco area may be wedge-shaped, conical or frusto-conical.

If the strong tobacco filling areas are wedge-shaped, conical or frusto-conical, they can extend over substantially the entire length of the tobacco rod.

If the wedge-shaped, conical or truncated conical portion does not extend over the entire length of the rod, the entire lighting end side can be made into a strong cigarette.

Substances that form strong tobacco blends include cured and hot-air-dried Burley tobacco leaves, Maryland tobacco leaves, Oriental tobacco leaves, etc., as well as Latikia (
Special tobacco leaves such as La-Ikia) tobacco leaves and open flame-dried tobacco leaves can be exemplified.

The materials forming the strong tobacco blend can include expanded tobacco leaves or small amounts of reconstituted tobacco sheets, treated petioles, and tobacco substitutes.

For mild blends of tobacco leaves, hot-air-dried mild types of burley tobacco leaves, Maryland tobacco leaves, Orient tobacco leaves, specialty tobacco leaves, etc. can be used.These mild tobacco leaves also include expanded tobacco leaves, expanded tobacco leaves, Reconstituted tobacco leaves, treated petioles, and tobacco substitutes can be included.

Preferably, reconstituted tobacco leaves, treated petioles, tobacco substitutes, etc. are used in the majority of the mild blend.

One of the filters that can be used in the present invention is described in European Patent Application No. 8
8308323.0 (Publication number 310゜257)
, the specification of which is hereby incorporated by reference. The filter includes a filter element of fibrous material, the fibers of which extend in a longitudinal direction between a first end, which is the end that is attached to the tobacco rod, and a second, opposite end. The filter element surrounds the tubular body extending in the longitudinal direction, one end of the tubular body is closed and located at the first end of the filter element, and the open end of the tubular body extends to the second end of the element. . The wall of the tubular body is provided with one or more radially extending holes near the closed end, which facilitates radial flow through the fibers of the filter element near the holes, thereby increasing the duration of the smoking period. Inside, a constant state of circulation is maintained through the wall of the tubular body.

This type of filter is equally effective in reverse mounting, where the open end of the tubular body is attached to the tobacco rod. Although the interior of the tubular body may be hollow or filled with a filtering material, it is preferable that the tubular body be formed of an impermeable film.

Another filter that can be used with the present invention is European Patent Application No. 89
310430.7 (Publication No. 364°256), the description of which is hereby incorporated by reference.

This filter is made from a layer of fine fibers with a diameter of 0
．． A barrier having a substantially plate-like disk shape of 5 to 10μ and one or more communication holes with a diameter of 0.1 to 3.0mm+ are provided, and the total area is 0.1 = lOLl1m2
It consists of a filter element with a flow path.

Disks of this structure can also be placed between layers of porous material to form a laminated barrier.

Yet another filter that can be used with the present invention is European Patent Application No. 89310421.6 (Publication No. 364.253
No.), the description of which is hereby cited as a reference. The filter includes an axially extending barrier tube made of fine fibers having a diameter of 0.5 to 10 microns and is arranged to allow at least a portion of the gas to flow through the wall of the barrier tube.

This barrier tubular body has a diameter of 0.1 to 3.011111
One or more circulation holes of 1 are provided, and the total area is 0.1~
It can be set to 10 mm2.

The barrier tubular body has a shape that can provide two coaxial passages, one inside and one outside, and one of the passages is closed at one end and the other passage is closed at the other end, thereby creating a flow path through the wall of the barrier tubular body. It is preferable to allow the formation of

In such a structure, the interior of the barrier tubular body can be hollow, and can also be filled with a filtering material.

The filter that can be used in the present invention is PCT Patent Application No. CA/
No. 90100070, the specification of which is hereby cited as a reference.

This filter consists of a cylinder of fine fibers wrapped in a regular filtration material.All of the smoke emitted from a cigarette is guided through the cylinder of fine fibers, and is guided through the cylinder of fine fibers. Smoke flow is directed so that the interior provides a filtered, low resistance smoke passage.

The present invention can be implemented in various ways, specific examples of which will be described below with reference to the accompanying drawings.

The cigarette of the present invention is wrapped with ordinary tobacco wrapping paper,
and a tobacco rod having a circular or oval cross-section filled with a divided area of at least two different types of smoke leaves or a blend of smoke leaves, and the tobacco leaves filled in the rod are , the tobacco leaf on the lighting end side of the rod is
It is filled to a higher level of strength, quality, flavor, and nicotine content than the tobacco at the smoke exit end.

In the specific example shown in FIG. 1, the area of the tobacco rod is in the shape of a segment, and the igniting end side indicated by the symbol (1) has a stronger cigarette than the other end side (2) from which smoke is discharged. It contains leaves. Note that the wrapping paper is not illustrated in the drawings.

The filter designated by code (3) is disclosed in European Patent Application No. 883.
No. 08323.0 (Publication No. 310,257). Any of the filters described in this document can be used in the present invention because they provide the required stepwise filtration effect. In the illustrated filter, the filter rod includes a plug jacket (6);
It consists of a fibrous material (4) and a tubular body (5) arranged along the length of the filter. One end of the tubular body (5) has the symbol (
It is folded closed as shown at 8), and the other open end is shown at (9). A pair of opposing holes (7) are provided in the wall of the tubular body near the closed end.

Details of this type of filter structure are shown in FIG.

Various features of the tubular body are shown in FIG. 2 of the above-cited European patent application, and other modifications may be employed in the present invention as described above.

When a cigarette fitted with the above-described filter is smoked, smoke enters the filter rod and travels inside the fibrous filter material until it reaches the pores of the tubular body. Here the smoke is divided into two streams, one flowing inside the fibrous filter material and the other flowing through the holes into the tubular body. The separated smoke streams within the tube only pass through the fibrous filtration material a short distance, so other smoke is not sufficiently filtered. Therefore, the tar condensation of the smoke stream leaving the tubular body in the first part is greater than that of the smoke leaving the filter body. As some of the smoke is separated into the tubular body through the holes, the smoke flow changes from initially being parallel to the fibers to being at an angle to the fibers. That is, the radial component of the flow increases significantly. Under such conditions, the fibers present in the smoke flow path intersect with the smoke flow direction. In addition to this, the velocity and momentum of the smoke particles is also greatly increased as they pass through narrow holes. The combination of an increase in the radial component of the smoke flow and an increase in the overall motion of the smoke particles greatly improves the filtration effectiveness of the fibers present in the vicinity of the pores.

That is, some of the smoke particles are precipitated and deposited in the pores and other parts are deposited on the fibrous material surrounding the pores. It has already been found that the size of the pores and the position of the pores can be selected such that the pores are not completely blocked by deposited smoke particles. In addition, by appropriately selecting the size and position of the holes, smoke particles accumulated on the fibers around the holes can increase the filtration efficiency of the fibers in accordance with the amount of smoke passing through the holes. . Therefore, in the initial stage of smoking, the smoke flowing inside the fibrous material is filtered only through the kernels, but as smoking continues, the filtration efficiency at the pores gradually increases, so the smoke flowing inside the material is gradually filtered. done effectively.

Therefore, tar condensation in the last few doses is greatly reduced. For this reason, cigarettes equipped with the above-mentioned filters have a more uniform and satisfactory tar release, and therefore, by combining the features of the filter with the two-part tobacco rod, the flavor and flavor when smoking are improved. The aroma can be substantially uniform.

In the structure of the tobacco rod shown in Fig. 2, the strong tobacco area (
1) is in the shape of a wedge, and that in Figure 3 is in the shape of a cone. Fourth
In the tobacco rod shown in the figure, the strong tobacco area (1) is truncated-conical. In all these constructions, mild tobacco fills the residual space of the rod. These wedge-shaped,
The strong tobacco in the conical and truncated conical shapes extends the entire length of the rod in the example shown, but if desired,
It can also extend over a portion of the total length.

In the construction shown in FIG. 5.6.7, the entire cross-section of the tobacco rod, up to a length of a few millimeters from the lighting end (10), is occupied by strong tobacco. Such a tobacco rod can be manufactured by the manufacturing method described in European Patent Application Publication No. 307°090. Other suitable structures are also described in this European patent application.

Ingredients that form strong tobacco blends include cured and hot-air dried Burley tobacco, Maryland tobacco, Oriental tobacco, as well as Latikia tobacco.
tikia) tobacco leaves, and special tobacco leaves such as open flame-dried tobacco leaves. If desired, expanded tobacco leaves or small amounts of reconstituted tobacco sheets, treated petioles, and tobacco substitutes can also be included.

Mild tobacco blends can include air-dried Valley tobacco, Maryland tobacco, Orient tobacco, mild specialty tobacco, etc., but generally at least some of these should be milder. is advantageous. Other materials that can be used in mild blends include expanded tobacco leaves, reconstituted tobacco leaves, treated petioles, and tobacco substitutes.

As mentioned above, a filter attached to one end of a tobacco rod containing a high proportion of mild tobacco leaves and having the property of increasing filtration efficiency with each edition of the smoking period is disclosed in European Patent Application No. 88308323.0 ( Publication number section 310, 25
The filter shown in FIG. 7 is another type of filter described in this European patent application. In this filter structure, the first to
The tubular body (5) shown in Figure 6 has been replaced by the impermeable film tubular body (12). Similar to the tubular body (5), the tubular body (12) has a hole (7), a closed end (14) and an open end (
15). The pores (7) communicate the fibrous materials (11) and (13). Preferably, the fibrous material (1
1) is packed with a lower density than the fibrous material (13). Furthermore, the fiber diameter should be as large as practicable. For example, denier/filament (dpf)
has a value of 5 to 15, and the total denier value is io, oo
.

Commonly available cellulose acetate tows of ~50,000 are suitable. The fibrous material (13) should be a filter medium with high filtration efficiency. 1.5 for fibrous material (13)
It is preferred to use commonly used cellulose acetate tows such as ~5 dpr, preferably 1.5-3.5 dpr.

When you smoke a cigarette with this filter attached,
Smoke enters the rod from the closed end (14) and this smoke initially flows through the material (13). On approaching the hole (7), the smoke splits into two parts, one of which flows directly into the material (13) and the other which flows through the hole (7) into the material (11). The two streams exit the filter rod from the end where the open end (15) is located. This filter is 1st to 6th
It has additional advantages compared to the filter shown in the figure. The main advantage is that the smoke flows into the material (11) from the hole (7) by collision, which causes the material (11) in the vicinity of the hole (7) to
) is to trap smoke particles. In other words, the substance (11
) not only functions as a filter medium inside the tubular body (12), but also functions as an impact surface for smoke particles near the holes (7). It is known that when a smoke particle passes through a narrow and confined passage, such as a hole (7), its velocity and momentum are significantly increased. These conditions are effective in trapping smoke particles onto the fibrous material (11) by impact. The fibrous material (11) intersects the smoke flow direction in the vicinity of the holes (7).

The trapped smoke particles are gradually deposited inside the material (11), which reduces the void volume in that part to some extent, thus further increasing the trapping efficiency. This action of the substance (11) in the vicinity of the pores (7) serves the purpose of gradually increasing the efficiency of the overall cigarette filter. If a fibrous material is selected for the material (11) that has a low packing density due to a large void volume or a large diameter, the pores (7
) and the open end (15) is not blocked during the smoking period. Therefore, the risk of a significant increase in the flow resistance of this channel must be avoided.

European Patent Application No. 88308323.0 (Publication No. 310
A filter of the type described above is particularly effective when the open end thereof is attached to a tobacco rod.

What is shown in Figure 9 is European Patent Application No. 89310430゜7.
(Publication No. 364,256). This filter rod has a tubular body (
24) and a barrier disk (23) with holes (24).
It consists of an element consisting of a barrier disk (2
3) is produced from a fine fiber layer with a diameter of 0.5 to lOμ. The tubular body (24) is made of conventional materials such as paper or plastic. The end of the disc (23) is glued to the inner wall of the tubular body (24), so that the longitudinal flow path within the tubular body (24) communicates with the disc (23). The number of holes (22) ranges from 1 to IO, preferably from 1 to 3. In the case of a single hole, it is preferred that the hole be located at or near the center of the disk. If multiple holes are employed, the holes can be uniformly distributed near the center of the disk, or each hole can vary in size and shape from the other holes. The disc may be manufactured from a plurality of fibrous layers, at least one of which
The layer consists of fine fibers with a diameter of 0.5-10μ.

This hole functions as a flow port and has a diameter of 0.1 to 3.
0 opening, the total flow opening area is in the range of 0.1~to++on''.The packing density of the fine fiber layer is 0.05~0.3, and the thickness is 0.5~4 m.

The advantage of this type of filter, as mentioned in the above-cited specification, is that a more average tar emission from plate to plate is obtained. The present invention takes the advantages of this filter and combines it with a multi-region tobacco rod to enable stage-averaged smoking.

FIG. 11 shows an alternative filter structure as described in European Patent Application No. 89310421.6 (Publication No. 364,253).

In this construction, the filter element is a barrier tubular body (
31), an outer tube having the shape of a plug jacket (33), and a porous material (34) filled in the gap between the tubular body (31) and the plug jacket (33); teeth,
Cellulose acetate, polypropylene, polymeric foam materials and suitable granules are used. If necessary, holes can be provided at appropriate locations. One end of the tubular body is numbered (36)
It is blocked as shown in .

The tubular body (31) can be made from a layer of fine fibers with a diameter of 0.5 to lOμ, and the porous material (34) can be made from a plurality of layers of fibers. At least one of the fiber layers consists of fine fibers with a diameter of 0.5 to 10 microns. The packing density of the fibers is 0.05-0.3, and the thickness is 0.5-0.3.
It is 2m.

The barrier tubular body (31) has a core material (38) made of a porous material, preferably a porous material with minimal gas flow resistance.
It surrounds. Commonly known filtration materials such as cellulose acetate or polypropylene tow can be used for the core material. The tow in this case preferably consists of coarse fibers of 5 denier/filament or more.

Also, this filtration material must be packed with low density.

This tubular body can also be provided with holes such as holes (7) in FIGS. 1-8. The provision of holes prevents the intrusion of fine fibers from clogging the tubular body and provides a flow opening to allow adequate leakage.

The advantages of this type of filter are described in the above-mentioned European patent specification, but filters of other constructions described therein can also be utilized in the present invention.

The filter described in PCT Patent Application No. CA/90100070 can also be used in the present invention and is incorporated herein by reference. A filter 4 of the type described here has similar advantages to the filter shown in FIGS. 11 and 12 in terms of high filtration efficiency.

By using a filter with high filtration efficiency, it is possible to pack a very strong tobacco at the lit end of the cigarette, which will not cause discomfort to the smoker even in the early stages of smoking.

Therefore, by increasing the difference in strength between the lighting end and the other end of the cigarette rod, it is possible to average out the smoking sensation for each garment.

When a tobacco rod made of tobacco leaves of different types is filled into divided areas and the above-mentioned filter that enables stepwise filtration is used in combination, it is possible to Compared to the case where only the cigarette filter described in the patent specification cited in 1999 is used, it is possible to make the smoking sensation of each garment more uniform. Therefore, the present invention has a special effect in that a cigarette that is welcomed by smokers can be obtained through the combination of a special filter and a cigarette rod having divided areas.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a cigarette according to the invention incorporating a filter of the type described in European Patent Application No. 88308323.0 (Publication No. 310,257). FIGS. 2, 3, 4 and 5 are cross-sectional views of cigarettes similar to FIG. 1, each differing only in the structure of the tobacco rod. FIG. 6 is a partially enlarged sectional view showing the structure of a filter that can be used in the present invention. FIG. 7 is a cross-sectional view of a cigarette similar to FIG. 5, which includes a filter whose tubular body is filled with tow serving as a filtering material. FIG. 8 is a partially enlarged sectional view of the filter used in the cigarette of FIG. 7. FIG. 9 is a cross-sectional view of a cigarette according to the invention having a filter structure as described in European Patent Application No. 89310430.7 (Publication No. 364.256). FIG. 10 is a partially enlarged sectional view of the filter used in the cigarette of FIG. 9. FIG. 11 is a cross-sectional view of a cigarette according to the invention having a filter structure as described in European Patent Application No. 89310421.6 (Publication No. 364,253). FIG. 12 is a partially enlarged sectional view of the filter used in the cigarette of FIG. 11. 9. Open end 10: Ignition end

Claims (1)

[Claims] 1. A cigarette rod in which the strength of the cigarette decreases from the ignition end to the other end, and a cigarette rod attached to one end of the rod opposite to the ignition end, which filters the cigarette as it burns out. A cigar or cigarette comprising a filter of increased efficiency. 2. The tobacco rod is made up of two or more divided areas filled with different types of tobacco leaves or a blend thereof, and the tobacco leaves or blend thereof filled on the ignition end side of the rod are
The cigarette of claim 1, which has a higher level of strength, quality, flavor, and/or nicotine content compared to the tobacco leaf or blend thereof filled in the smoke outlet side of the rod. 3. A cigarette according to claim 2, wherein the region filled with strong tobacco is wedge-shaped, conical or truncated-conical. 4. A cigarette according to claim 3, wherein the wedge-shaped, conical or frusto-conical region filled with strong tobacco extends over substantially the entire length of the tobacco rod. 5. The cigarette according to claim 1, wherein the wedge-shaped, conical or frusto-conical region filled with strong tobacco extends over a part of the entire length of the tobacco rod, and the lighting end is entirely composed of strong tobacco. . 6. The substance forming the strong tobacco blend includes burley tobacco leaves, Maryland tobacco leaves, Oriental tobacco leaves, or specialty tobacco leaves that have been cured and aged and hot-air dried. cigarettes. 7. The cigarette according to claim 6, wherein the special tobacco leaves include Latikia tobacco leaves or flame-dried tobacco leaves. 8. The cigarette of claim 6 or 7, wherein the materials forming the strong tobacco blend include expanded tobacco leaves or small amounts of reconstituted tobacco sheets, treated petioles, and tobacco substitutes. 9. The substance forming the mild tobacco leaf blend includes hot air-dried mild Burley tobacco leaves, Maryland tobacco leaves, Orient tobacco leaves, or specialty tobacco leaves according to any one of claims 1 to 8. Cigarettes. 10. The cigarette of claim 9, wherein the materials forming the mild tobacco blend include expanded tobacco leaves, reconstituted tobacco leaves, treated petioles, or tobacco substitutes. 11. The cigarette of claim 10, wherein the expanded tobacco leaf, reconstituted tobacco leaf, treated petiole or tobacco substitute constitutes the majority of the blend. 12. The filter to be attached to the tobacco rod is composed of a filter element made of a fibrous material, and the fibers of the element are arranged between a first end, which is the end to be attached to the tobacco rod, and a second end, which is the opposite end. The tubular body extends in the longitudinal direction and surrounds the longitudinally extending tubular body, the end of the tubular body located on the first end side is closed, the open end of the tubular body extends to the second end, and the tubular body The body tube wall is provided with one or more radially extending holes near the closed end thereof to facilitate radial flow, and the holes are sized to remain unobstructed during the smoking period. The cigarette according to item 11. 13. The cigarette according to claim 12, wherein the filter is attached in the opposite direction so that the open end side of the tubular body contacts the tobacco rod. 14. The cigarette according to claim 12 or 13, wherein the inside of the tubular body is hollow. 15. The cigarette according to claim 12 or 13, wherein the inside of the tubular body is filled with a filtering material. 16. Claim 1, wherein the tubular body is made of an impermeable film.
The cigarette according to any one of items 2 to 15. 17. A substantially plate-like disk barrier formed from a layer of fine fibers with a diameter of 0.5 to 10 microns is provided in the smoke flow passage of the filter;
One or more flow ports with a total flow port area of 0.1 to 10 mm
A cigarette according to any one of claims 1 to 11, characterized in that a filter having a diameter of mm^2 is attached to the tobacco rod. 18. The cigarette of claim 17, wherein the disc is positioned between porous materials to form a laminated barrier. 19. A filter consisting of a barrier tubular body made of fine fibers with a diameter of 0.5 to 10 microns and extending in the axial direction so that at least part of the gas flows through the tubular wall was attached to the tobacco rod. The cigarette according to any one of claims 1 to 11. 20. The cigarette according to claim 19, wherein the barrier tubular body has one or more flow ports having a diameter of 0.1 to 3.0 mm, with a total flow port area ranging from 0.1 to 10 mm^2. 21. The barrier tubular body has a shape with two coaxial inner and outer passages, and one of the passages is closed at one end and the other passage is closed at the other end, so that gas flows through the wall of the tubular body. The cigarette according to claim 19 or 20. 22. The cigarette according to claim 21, wherein the barrier tubular body is hollow. 23. Claim 2, wherein the inside of the barrier tubular body is filled with a filtering material.
The cigarette according to item 1. 24. The filter attached to the tobacco rod consists of an annular body of ordinary filter material surrounding a cylindrical body of fine fibers,
Claims 1 to 11, characterized in that all the smoke emitted from the tobacco rod passes through an annular body of ordinary filtering material, and a low resistance passage for filtered smoke is provided inside the cylinder of fine fibers. Cigarettes.