KR101538002B1 - Tobacco smoke filter - Google Patents

Abstract

An air permeable axial core, a first wrapper around the peripheral surface of the core and made of an air permeable material, and a second wrapper around the first wrapper, wherein the first wrapper includes at least Defines at least one channel extending longitudinally from the top of the filter and at least one channel extending longitudinally from the bottom of the filter together with the second wrapper, Wherein at least a portion of the filter does not have a longitudinally extending channel.

Filter, cigarette, wrapping paper with wrinkles, wrapping paper without wrinkles, flute part, bar part, channel

Description

Tobacco smoke filter {TOBACCO SMOKE FILTER}

The present invention relates to a cigarette smoke filter, particularly a cigarette smoke filter.

The cigarette filter is known to include an inner wrapper and an outer wrapper as a filter core and two filter wrappers. The wrapping paper has a groove along a regular section in its length direction by embossing treatment. Each filter will include a wrapping flute (flute) with its bobbin of predetermined length and a wrapping bar (bar) without grooves. The filters are made as continuous rods including flutes and bars, and the continuous rods are then cut into a length (single filter or multiple filters) for use in the manufacturing step; The cutting takes place in the middle of the flute and bar. Therefore, one end of the filter will have an end shape with a groove due to the flute, and the other end will have an end shape or blank shape with no groove. The end shape with the groove may be located at the mouth end of the filter if a new end shape is desired and at the tobacco end if a conventional end shape is desired.

The limitations of this kind of filter are that, under mass production conditions, even if the bar / flute structure of the continuous bar is slightly drifted against the cutting device, the pressure drop of the product filter may change. This point will be discussed later in more detail.

Applicants have discovered that the filter is always cut at both ends in the flute region by placing the bar region within the filter rather than at one end. The bar length will not be affected by variations in cutting, and the performance of the final filter (eg, pressure drop) will be more constant.

According to the present invention, there is provided a cigarette smoke filter comprising: an air permeable axial core; a first wrapper around the peripheral surface of the core and made of an air permeable material; Wherein the first wrapping paper comprises at least one channel extending longitudinally from the top of the filter and at least one channel extending longitudinally from the bottom of the filter with at least a second wrapping paper, Defining at least one channel, each channel extending only over a portion of the core length, and at least a portion of the filter having no longitudinally extending channels.

Preferably, the length of each channel is at least 2 mm, more preferably from 2.5 mm to 23 mm, even more preferably from 3 mm to 15 mm, and still more preferably from 3.5 mm to 9 mm. Channels or channels extending from one end (upward or downward) may be of a different length than the channels extending from the other end, or they may be the same length. The channels at both ends of the filter can have a length of 7 mm - 8 mm. The channels at both ends of the filter may have a length of 3 mm to 4 mm, for example 3.75 mm. Having a channel of this dimension means that the performance of the filter (such as tar retention) will be acceptable and additionally makes it possible to reliably achieve the advantages of the invention (e.g. constant pressure drop, improved retention).

The channels are preferably at a substantially constant depth throughout the length direction, although, for example, there may be a change in the portion where the channel is close to the closed end.

The first wrapping paper may be, for example, a sheet having a profile (e.g., corrugated) surface, which is wrapped in a profile side facing the second wrapping paper. The first wrapper preferably includes wrinkles extending in the longitudinal direction (axial direction), the wrinkles defining the channels extending longitudinally with at least the second wrapping paper. Each channel is closed or blocked at the other end remote from the end of the filter from which the channel begins to extend and may be provided by the corrugation of the first wrapper. The first wrapper has corrugations on both surfaces and can define channels extending longitudinally with the core as well as the second wrapper. However, the packaged core surface may conform to the shape of the corrugated inner surface of the first wrapper in the finished filter, leaving a channel only between the first wrapper and the second wrapper.

The finished filter according to the present invention may include a second wrapper around the first (e.g., corrugated) wrapper to provide air permeability (which may or may not have inherently permeable material). Such a transparent outer wrapper may be a tipping overwrap, and the tipping overlap causes the filter to be incorporated into the filter cigarette, which is applied only in the cigarette manufacturing step. In this case, the filter rod is initially fabricated with the first wrapping paper exposed, and the present invention includes such a rod as well as the finished filter with the outer wrapping paper attached. The filters may also be used with a second wrapper (e.g., a tipping overlap) that is air permeable.

The portion of the filter that contains the longitudinal channels (e.g. including wrinkles) is hereinafter referred to as the flute (d) portion. A portion of the filter that does not include a longitudinal channel (on the filter section) is referred to as a bar or bar portion. In one embodiment, the filter according to the present invention comprises a single central bar portion corresponding to the remaining length of the filter and a 3 mm flute portion at each end. This structure has the advantage that the amount of tow of the filter material (e.g., cellulose acetate) in the core can be reduced because the pressure drop (PD / mm) of the bar portion is higher than the pressure drop of the flute portion. Such a structure can also provide a more desirable end of the appearance.

The present invention also provides a method of manufacturing a tobacco smoke filter comprising providing an air permeable axially extending core, forming a first wrapper of air permeable material around the core, Wherein the first wrapping paper comprises at least one channel extending longitudinally from the top of the filter and at least one channel extending longitudinally from the bottom of the filter with at least a second wrapping paper, Defining at least one channel, each channel extending only over a portion of the core length, at least a portion of the filter having no longitudinally extending channels, the filter being a continuous Wherein the step of forming the individual filter by cutting the continuous rods comprises the steps of forming the upper end of the filter and the lower end of the filter It is adjusted.

The cigarette smoke filter may include no more than 23, preferably 14-20, channels extending from each end (top and bottom) of the filter (filter with a circumference of about 25 mm). The total cross-sectional area of these channels may reach 2-12%, preferably about 4% or more, and more preferably 4-8% of the total cross-sectional area of the filter. Therefore, filter performance can be improved by carefully adjusting the number and / or depth of the channels (e.g., by controlling the embossing of the first wrapping paper). This improvement in filter performance can be achieved by increasing the depth of the wrinkles, preferably by increasing the surface area of the wrinkles used to deliver the smoke, optionally by increasing the pitch of the wrinkles, Can be achieved by reducing the number of wrinkles. For example, a filter according to the present invention may have fifteen channels at each end of the filter, with a depth of about 0.45 mm, a pitch of about 1.5 mm, and other filters having a channel of 0.32 mm depth , The number of channels at each end is 23, and the pitch is 1.05 mm. The area of the corrugated wrapper used in smoke filtration in these embodiments is generally slightly less than the total corrugated surface area since the crease of the corrugations generally abuts the outer wrapper and is not effective for the filter.

The filter according to the present invention can be applied to a cigarette by conventional means, for example a ring tipping, a narrow strip of paper bonded only around the abutting ends of the tobacco rod and filter, 2 The wrapper is exposed. In other cases, the cigarette and the filter may be joined by, for example, a tipping overlap surrounding the second wrapper over the entire length.

In the case of a typical structure according to the invention, as indicated by the embodiments described below, the total length of the bar portion (s) per filter is always completely within the filter tip. Thus, even though the bar / flute structure or marking is likely to drift slightly during the manufacturing process, there will always be bar portions and flute portions of the same length in the tip. Thus, the bar / flute ratio will remain constant and the potential source of PD variation will be eliminated.

Also, since there is a point at which the flute portion and the bar portion meet in the filter (at the end of each channel), the high tar reduction performance of this kind of filter will be maintained, as discussed below.

In another embodiment of the present invention, the cigarette smoke filter comprises at least one channel defined by a first wrapper and at least a second wrapper, the channel extending in the longitudinal direction of the filter, But extends only over a portion and does not extend from the top or bottom of the filter. In this embodiment of the invention, the cigarette smoke filter comprises at least one longitudinal channel (first flute portion) at the top of the filter; One or more longitudinal channels (second flute portion) at the bottom of the filter; And additional longitudinal channels or channels (additional flute portions) within the filter. In this embodiment, there is one or more filter portions or sections (one or more bar portions) that do not have longitudinal channels. The filter may have additional flutes and / or bar areas.

In another embodiment of the present invention, the second wrapping paper is made of color material, for example color paper.

In the present specification, the term "colored material (color material)" refers to a color different from white or slightly hazy white (i.e., a material having a different color tone (e.g., paper)). The filter of the present invention comprises an air permeable axially extending core of cigarette smoke filter material. Filters are usually made of tobacco smoke filter material, such as white or slightly turbid white cellulose acetate tow. "Colorized" means having a pigment or tint or color that is not white or slightly hazy white, e.g., different from the color of the cellulose acetate tow, and the color of the second wrapping paper and the air of the cigarette smoke filter material For example, black, red, yellow, pink, green, orange, brown, purple or blue and / or a variety of shades that provide a noticeable difference or contrast between the transparent axially extending cores .

The inventors have surprisingly found that introducing a second wrapping paper of color material, for example color paper, around a first wrapping paper of, for example, a corrugated, air-permeable material significantly improves the visual impression of the flute portion (A visual impression is improved compared to using a first color wrapper (e.g., a corrugated wrapper) with a second wrapper that has no color (white or turbid white). The visual impression of this significantly improved flute portion (which can be further improved or changed by changing the number of corrugations (longitudinal channels) and / or corrugations (longitudinal channels) of the first wrapper) Can be used as counterfeit preventing means since it is observable at the mouth end of the filter (whether applied to cigarettes or not).

The second colored wrapping paper may be surrounded by additional packaging material (e.g., a tipping overlap), which may be white or turbid white or colored, further enhancing the visual impression / contrast.

It will be understood that the filter according to this embodiment can be applied to a cigarette by conventional means as described above.

In another aspect, in accordance with the present invention, there is provided a cigarette smoke filter comprising: an air permeable, axially extending core (of a cigarette smoke filter material); a first wrapping around the core, And a second wrapper ply around the first wrapper, wherein the first wrapper has a longitudinally extending crease extending between at least a first wrapper and a second wrapper, at least extending longitudinally from one end of the filter, And the second wrapping paper is made of a color material.

Preferably, the channel extends longitudinally from the mouth end of the filter so that a channel (flute) can be observed from the mouth end of the filter when the filter is attached to a rod of tobacco material to form a cigarette.

The cigarette smoke filter may comprise up to 23 channels, preferably 14-20 channels, extending from at least one end of the filter (filter with a circumference of about 25 mm). The total cross-sectional area of these channels may reach 2-12%, preferably about 4% or more, and more preferably 4-8% of the total cross-sectional area of the filter. As discussed in the previous section, filter performance can be improved by closely adjusting the number and / or depth of the channels (e.g., by controlling the embossing of the first wrapping paper). Further, by carefully adjusting the number and / or width of the channels in combination with the second wrapping paper in color, the visual impression of the channel (flute) portion can be conspicuously marked, which can be used as counterfeit prevention means have.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail by way of embodiments with reference to the accompanying drawings.

FIG. 1 is a perspective view of a filter according to an embodiment of the present invention, which is not shown at a constant ratio, but shows a partially exploded perspective view.

Figure 2 is a schematic side cross-sectional view of a rod of multiple lengths according to the prior art, which is not shown at a constant rate but which shows how the rod can be cut into a plurality of individual filter lengths.

Figure 3 is a similar view of a rod of multiple lengths according to the present invention, showing how the rod can be cut into a plurality of individual filter lengths and is related to the removal of a potential source of PD variation Thereby demonstrating the advantages of the present invention.

FIG. 4 is a perspective view of a filter according to another embodiment of the present invention, which is not shown at a constant ratio, but shows a partially exploded perspective view.

In the filter shown in Fig. 1, the filter 1 comprises a core 2 made of crimped cellulose acetate filaments. The filaments are bonded to each other by a solvent plasticizer such as triacetin at their point of contact. The periphery of the core 2 is wrapped with a wrapper 3 made of air permeable filter paper (or corrugated cellulose acetate) which extends from its periphery 6 in the central or central section 7 of the filter over its entire length It has wrinkles in the longitudinal direction. The core surface conforms to the corrugation of the wrapper 3. The channels 5a and 5b are formed around the wrapping paper 3 by wrinkles to form a wrapping paper 4 that is free of air permeable wrinkles. The core and wrapping paper (3, 4) extend over the entire length of the filter (1). The formation of a peripheral portion 6 without wrinkles on the wrapping paper 3 at the center of the filter means that no channel is present in this portion and that the channels 5a and 5b do not extend over the full length of the filter do. The filter 1 therefore has a first set of channels 7.5 mm long (formed between the corrugated portion of the wrapping paper 3 and the wrapping paper 4 free of air permeability) at the first or lower end 9 of the filter And a second set of channels 5b having a length of 7.5 mm (formed between the corrugated portion of the wrapping paper 3 and the wrapping paper 4 without air permeability) at the second end or the upper end 11 of the filter Which form a flute or flute at each end 9, 11 of the filter 1. At the center of the filter, the wrinkle free area of the wrapper 3 in the peripheral part 6 forms a 6 mm long wrinkle free or flute free bar part (bar) at the center of the filter. This bar portion blocks the channel end opposite the filter end from which the channel extends. The bar portion of the filter does not include a longitudinally extending channel across the cross section of the filter 1 along the entire length of the bar portion.

In use, an end 11 of the filter is attached to the cigarette, and a portion of the smoke enters the core 2 directly, passes through the end of the filter 1, and is filtered by contact with the filament forming the core. In this embodiment, since the air-permeable wrapper 4 is present, diluting air will also be sucked into the filter. The smoke enters the channel 5b with the diluted air sucked through the transparent wrapping paper 4 and enters the wrinkle free portion 6. The diluted smoke passes through the corrugated wrapping paper 3 and then flows into the core 2 And then goes through the filter through the other end: therefore this smoke is filtered by both the wrapping paper 3 and the core 2. The filter according to the invention may also be used with non-breathable wrapping paper, in which case there will be no dilution air being drawn through the wrapping paper.

The filter 1 may be attached to the cigarette by, for example, ring-tipping or full tipping overwrap, which method is well known in the art. Other materials known in the art can also be used to form the core 2 and the wrapping paper 3, 4.

Fig. 2 is a bar 51 of a filter according to the prior art, which has a multiple length. The rod 51 is composed of a filter core and two filter wrapping inner wrapping paper and outer wrapping paper (not shown). Filter rods having multiple lengths are made by methods well known in the art. Therefore, a known device feeds a tow of crimped plasticised filaments of cellulose acetate to the garniture. At this time, they are enwrapped by corrugated cellulose acetate or paper strips. This strip is formed by feeding a crimped and plasticized filament (or paper) tow to a heated block with a steam block followed by a heated, grooved roller with a short, lengthwise spaced, non-embossed area do. Therefore, the wrapping paper is regularly grooved along its length by embossing as a first layer of air-permeable material. The strip of inner wrapper is positioned before the adjustable guide enters the garniture so that strips of inner wrapper are wrapped around the tow in the lengthwise direction so that both edges of the strip of inner wrapper are tangent to each other. From the bobbin, a strip of paper (second wrapping paper) enters the adhesive printing apparatus, which applies the adhesive on the strip at a suitable location along the horizontal line to form a strip of corrugated cellulose (or paper) And the paper strip as the second wrapping paper meet at the garment, the lines of adhesive material come into contact with the unembossed areas of the strip of corrugated cellulose acetate (paper), which is the wrapping paper. The adhesive apparatus is also characterized in that when the strip of paper as the second wrapping paper enters the garniture and surrounds the filament and the strip of wrapping paper, the overlapping edge of the strip of paper as the second wrapping paper is sealed by a heater according to a known method ). The guide accurately positions the strip of paper. Therefore, a continuous rod composed of a filter core and two filter wrappers made of an inner wrapper and an outer wrapper is formed and passed through a cutter which is divided into rods 51 having a plurality of lengths as shown in Fig. 2, Each rod has a length that is a multiple of the length of the final filter to be attached to the product to be fumed. A plurality of double-length rods 51 manufactured in this manner include a plurality of wrapping pads (flutes) 52 having grooves and a plurality of wrapping pads (bars) 53 and 54 having no grooves. (Using techniques well known in the art), the rod 51 of multiple lengths is cut by the penetration of the flutes 52 and bars 54 in the area indicated by the arrow 55, It is made of four filters with one flute and one bar at the other end. One end of each filter will have an end shape with a groove due to the flute and the other end will have a blank shape without a groove due to the bar. The end shape with the groove may be located at the mouth end of the filter if a new end shape is desired and may be located at the tobacco end if a conventional end shape is desired.

In a manufacturing process of a 21 mm long filter tip with a defined flute length of 15 mm and a defined bar length of 6 mm, the filter will be manufactured as a continuous bar with a 30 mm flute 52 and a 12 mm bar 53 . The feed rods are cut to a defined length and due to the nature of the mass production process there is a possibility of slight drift to the bar / flute structure for the cutting device. When such drifting occurs, the cutting may not be done directly in the middle of the flute or bar undesirably. Therefore, if a drift of +/- 1 mm occurs, the desired structure of the 15 mm flute and the 6 mm bar will vary between the structure of the 16 mm flute and the 5 mm bar and the structure of the 14 mm flute and 7 mm bar There is a possibility. The pressure drop in the bar portion (water at several millimeters of water: PD-mm) is significantly higher than the PD-mm in the flute portion, and a change in the desired length of bar and flute in the filter is likely to result in a change in PD : A tip PD change of 77-90 mm was observed in the test. 2 shows that a plurality of rods 51 are drifted to the position shown by the rods 51a (the arrows 55 (see FIG. 2), which are intended to cut the rods at the correct positions corresponding to the rods 51 ), The size of the flutes and bars at each cut may be different from the desired level.

Fig. 3 shows a rod 61 of multiple lengths of a filter according to the invention (for example a filter according to Fig. 1). The rod 61 is again composed of a filter core and two filter wrappers made of inner wrapper and outer wrapper. The wrapping paper has grooves regularly along its length by embossing. This process is well known in the art and has been described above with reference to FIG. The rod 61 having a plurality of lengths includes a plurality of wrapping pads (flutes) 63, 63a, 63b having grooves and a plurality of wrapping pads (bars) 62 having no grooves. The length of each bar portion 62 is 6 mm, and the length of each flute portion 63 is 15 mm. (Using techniques well known in the art), in accordance with one embodiment of the present invention, the rod 61 having a multiple length is cut in the region indicated by the arrow 65 passing through the flute 63, So that four filters are formed, each filter having a flute at each end and a bar 62 between the flutes.

1, in the process of manufacturing a 21 mm long filter tip with a flute of a predetermined length of 7.5 mm at both ends and a bar of a predetermined length of 6 mm, as described with reference to Fig. 1, The filter will be manufactured as a continuous bar with a 15 mm flute and a 6 mm bar. The raising rod is cut to a predetermined length. If slight drifting occurs in the bar / flute structure with respect to the cutting device, the length of the flute and bar in the tip will always be the same, even if the cutting does not occur preferably in the middle of the flute. 3A shows a schematic view of a preferred filter with two flutes 5a and 5b each 7.5 mm long separated by a bar 6 of 6 mm length. If drifting occurs, the structure may be as shown for example in Figure 3b. This structure includes a 6 mm flute 5e and a 9 mm flute 5f separated by a 6 mm bar 6g: the overall bar / flute ratio of the filter is constant, The cause is removed.

In the filter shown in Fig. 4, the filter 101 includes a core 102 made of crimped filaments made of cellulose acetate. They are bound to each other at the point of contact by a solvent plasticizer such as triacetin. Immediately surrounding the core 102 is a wrapper 102 made of air permeable filter paper and has a longitudinal fold away from the two peripheral portions 106 and 106a over its entire length. The core surface conforms to the corrugation of the wrapping paper 103. The wrapping paper 104 immediately surrounding the wrapping paper 103 and formed of wrinkles to form the channels 105a, 105b and 105c is an air-permeable paper having no wrinkles. The core and the wrapping paper 103, 104 extend over the entire length of the filter 1. Placing the peripheral portions 106, 106a on the filter without wrinkles in the portion of the wrapping paper 103 means that there are no channels in this portion and that the channels do not extend over the entire length of the filter. The filter 1 therefore has a first set of channels 105a of 3.75 mm in length formed at the first or lower end 109 of the filter (the corrugated portion of the wrapping paper 103 and the wrapper 104 without air- And a second set (formed between the corrugated portion of the wrapping paper 103 and the air-permeable wrinkle-free wrapping paper 104) of the channel 105b having a length of 3.75 mm at the second or upper end of the filter These folds form a flute portion at each end 109, 111 of the filter 101. A third set of channels 105c (formed between the corrugated portion of the wrapping paper 103 and the air-permeable wrinkle-free wrapping paper 104) of 7.5 mm in length is located in the center portion of the filter. The pleated area of the wrapping paper 103 in the peripheral portions 106 and 106a is divided into two wrinkle-free or flute-free 3 mm long bar portions (separated by a third set of channels 105c) Respectively. The bar portion blocks the end of each channel that is touching. The bar portion of the filter does not include a longitudinally extending channel across the cross section of the filter 101 along the entire length of the bar portion.

The filter 101 may be attached to the cigarette, for example, by ring-tipping or pull-tipping overlap, and such methods are well known in the art.

The embodiment shown in Fig. 4 can be used, for example, where it is desirable to have the filter breathable and to position the additional flap area 105c below the vent area.

It will be appreciated that the filter 101 of FIG. 4 is symmetrical (as shown in FIG. 1). As will be appreciated by those skilled in the art, asymmetric structures are possible and are within the scope of the present invention. For example, a filter similar to the structure shown in Fig. 1, 21 mm long, with 5 mm and 11 mm flutes separated by a 5 mm bar may be another example of the present invention.

In a further embodiment (not shown) of the present invention, a filter similar to the filter shown in Fig. 1 described above is used instead of the wrapper 104 made of air permeable paper, instead of the air- Lt; / RTI > This provides a very strong visual impression by having a wrinkle (flute) region at the mouth end of the filter. In another embodiment (not shown) of the present invention, a filter similar to the filter shown in FIG. 4 described above is used instead of the wrapper 104 made of air- I have wrapping paper. This provides a very strong visual impression by having a wrinkle (flute) region at the mouth end of the filter.

Additional Embodiment

Three different cigarette filter designs were prepared. Two of these (Comparative Examples A and B) were produced according to the prior art (manufactured, for example, by the method described with reference to Figure 2), wherein the filter was cut off nominally between the flute and the bar region. The other type of filter (Example C) was prepared according to the present invention (for example, by the method described with reference to Fig. 3). The filter tips of Comparative Examples A and B are of a structure having a 4 mm bar and a 5 mm flute, whereas the filter tips of Example C are of the same overall dimensions and have a 2.5 mm flute + 4 mm bar + 2.5 mm flute .

After manufacture, a single cut was made along the length of the wrapper of each filter tip, and the wrapper was carefully removed from the tip. The length of the bar area of each filter tip was measured. The 20 tips of each design were measured in this manner and the results obtained are shown in the following table.

tip Nominal bar length (mm) Measured bar length (mm) Minimum Maximum Average S.D. * Comparative Example A 4.0 3.0 4.0 3.7 0.38 Comparative Example B 4.0 2.0 4.5 3.7 0.52  Example C 4.0 4.0 4.0 4.0 0.00

* Standard Deviation

It can be seen that the present invention eliminates deviations in measured bar length.

Claims (16)

An air permeable axial core, a first wrapper around the peripheral surface of the core and made of an air permeable material, and a second wrapper around the first wrapper, wherein the first wrapper includes at least Defines at least one channel extending longitudinally from the top of the filter and at least one channel extending longitudinally from the bottom of the filter together with the second wrapper, Wherein at least a portion of the filter has no longitudinally extending channels over the filter cross-section. The cigarette smoke filter according to claim 1, wherein each channel has a length of 2 mm or more. The cigarette smoke filter according to claim 1, wherein the length of each channel is 2.5 mm to 23 mm. 4. The absorbent article of claim 1, wherein the first wrapper has a longitudinally extending pleat defining a longitudinally extending channel with at least the second wrapper, Wherein at least one channel extending in a longitudinal direction from a lower end of the filter is closed at a channel end farther from the top of the filter than at least one channel extending away from the lower end of the filter Wherein the cigarette smoke filter is closed or blocked at the channel end. 4. The filter according to any one of claims 1 to 3, further comprising at least one additional channel defined by the first wrapper and at least the second wrapper, the additional channel extending in the longitudinal direction of the filter, Extends only to a portion of the length and does not extend from the top or bottom of the filter. The filter according to any one of claims 1 to 3, comprising up to 23 channels extending longitudinally from each end of the filter, the total cross-sectional area of the channels being 2-12% of the total cross-sectional area of the filter Features a cigarette smoke filter. 7. The cigarette smoke filter according to claim 6, wherein each end of the filter includes longitudinal channel (s) occupying at least 4% of the total cross-sectional area of the filter. The cigarette smoke filter according to any one of claims 1 to 3, wherein the second wrapping paper is air-permeable. The cigarette smoke filter according to any one of claims 1 to 3, wherein the second wrapping paper is air impermeable. The cigarette smoke filter according to any one of claims 1 to 3, wherein the second wrapping paper is colored. delete The cigarette smoke filter according to any one of claims 1 to 3, characterized in that it does not have a second wrapping paper. Wherein one end of the filter is coupled to a packed cigarette rod, and wherein the filter is a filter according to any one of claims 1 to 3. A method of manufacturing a cigarette smoke filter, Providing an air permeable axially extending core, forming a first wrapping paper of an air permeable material around the core, and surrounding the wrapped core with a second wrapping paper, wherein the first wrapping paper At least one channel extending longitudinally from the top of the filter and at least one channel extending longitudinally from the bottom of the filter, wherein each channel defines at least a portion of the length of the core Wherein at least a portion of the filter does not have a longitudinally extending channel over the filter cross section, the filter is formed as a continuous bar of a plurality of filters, the continuous bar is cut to form an individual filter Wherein the cutting end is adjusted to form a top end of the filter and a bottom end of the filter. And an air permeable second wrapper disposed around the first wrapper, the first wrapper including a core extending in the axial direction, an air permeable core disposed around the core, a first wrapper made of an air permeable material, Wherein each channel extends through at least a portion of the length of the core to provide a channel extending longitudinally from at least one end of the filter between at least the first wrapping paper and the second wrapping paper, Wherein at least a portion of the filter does not have a longitudinally extending channel over the filter cross section and the second wrapping paper is made of color material. Wherein one end of the filter is coupled to a packed tobacco rod, and the filter is the filter according to claim 15.

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