JP6367404B2 - Breathable smoking article containing an adsorbent - Google Patents

Description

  The present invention relates to a vented smoking article incorporating a filter wrapper with an adsorbent.

  In general, a cigarette with a filter includes a tobacco cut filler rod wrapped with a wrapping paper, and a cylindrical filter that is aligned with the wrapped tobacco rod in contact with the ends and attached to the tobacco rod with chipping paper. Prepare. In a conventional cigarette with a filter, the filter consists of a plug of cellulose acetate tow wrapped with a porous plug wrap.

  It is common to provide a smoking article with a vent zone in the form of a perforation provided in a chipping paper or plug wrap, or both. The ventilation zone allows air to flow into the filter during smoking, and the air dilutes mainstream smoke coming through the filter from the burning tobacco rod, thus reducing the level of smoke components delivered to the consumer.

  In general, a ventilation zone includes perforations provided at one or more locations along the filter of a smoking article, some of which are accidentally occluded during smoking, for example, by a consumer's lips or fingers. May be. Therefore, the flow of air into the filter is blocked and the dilution level of mainstream smoke is reduced.

  In addition to providing a ventilation zone, it is known to provide an adsorbent such as activated carbon in the filter of a smoking article as an additional means of reducing the level of certain smoke components. However, adsorbents can adversely affect the flavor of mainstream smoke and may not be preferred by some consumers.

European Patent No. 1,958,523

  To ensure that accidental ventilation zone concealment does not significantly affect smoke component delivery, the delivery level of a particular smoke component is substantially reduced regardless of whether the ventilation zone is unoccluded or occluded. It would be desirable to provide a novel filter configuration for the smoking article to maintain. Furthermore, it would be desirable to be able to easily manufacture such a filter arrangement using existing equipment and technology.

According to the present invention, a smoking article is provided, the smoking article comprising a tobacco rod and a filter including one or more filter segments connected to the tobacco rod and surrounded by a filter wrapper containing an adsorbent. . The filter includes a ventilation zone provided upstream of the adsorbent. With this configuration, the level of mainstream gas phase smoke component delivered during smoking with the ventilation zone unoccupied is such that the mainstream gas phase smoke component delivered during smoking of the smoking article with the ventilation zone blocked. The maximum level is within 40%.

The ventilation zone, which can be referred to as an array of perforations or holes provided on the filter, allows the ventilation of the filter and dilution of mainstream smoke by smoking when air flows into the filter through the holes. If the ventilation zone is not completely covered, it is “not blocked” and air freely flows into the filter when smoking. When the ventilation zone is covered or closed, it is “clogged” and air is prevented from entering the filter through the ventilation zone. In the present invention, the level of the vapor phase mainstream smoke component delivered when smoking the smoking article when the ventilation zone is occluded is the same delivered when smoking the smoking article when the ventilation zone is not occluded Within a maximum of 40% of the level of mainstream gas phase smoke component. Preferably, the level of gas phase smoke component delivered with the vent zone blocked is within a range of up to 30% of the level delivered with the vent zone unblocked, more preferably up to 20 percent in the range, and most preferably in the range of up to 10%.

  In the context of the present invention, the term “smoke component” is intended to refer to the gas phase component of mainstream smoke. In particular, the smoke components shown herein are gas phase carbonyl compounds, including aldehyde and ketone compounds. For example, the gas phase component can include one or more of formaldehyde, acetaldehyde, acetone, and acrolein.

  In the present invention, the level of mainstream gas phase smoke component delivered during smoking of a smoking article with the vent zone unoccupied is determined by the smoking article absorbing 35 ml with a duration of 2 seconds every 60 seconds. ) Is required by smoking. In the ISO test method, the smoking article is smoked without completely covering the ventilation zone. In the present invention, the level of mainstream gas phase smoke component is normalized to nicotine delivery, and the level is given in mg of nicotine.

  The level of mainstream gas phase smoke component delivered during smoking of a smoking article with the ventilation zone according to the present invention blocked is 55 ml with a Health Canada smoking test (duration of 2 seconds every 30 seconds). Can be obtained by smoking a smoking article. In the Health Canada smoking test, the chipping paper is covered by an air impermeable film or tape so that air cannot flow through the vent zone and into the filter, and the mainstream smoke dilution is approximately 0%. As mentioned above, in the present invention, the level of mainstream smoke component is normalized to nicotine delivery, so the level is given in mg of nicotine.

  The level of the gas phase smoke component of the mainstream smoke is determined as an average value of 20 samples of smoking articles with the ventilation zone not blocked and 20 samples of smoking articles with the ventilation zone blocked. The level of smoke component is measured by the total amount of carbonyl compounds. The present invention provides an effective method of maintaining a relatively constant delivery of the gas phase smoke component of a vented smoking article regardless of whether the vent zone is occluded or occluded.

  In the present invention, the adsorbent is placed in the filter of the smoking article, so in normal smoking conditions where the ventilation zone is not blocked, dilution of mainstream smoke by air flowing into the filter through the ventilation zone is: This is the main mechanism for reducing the smoke component level in mainstream smoke. Ventilation air will provide an air cushion that isolates most of the mainstream smoke from the adsorbent. Thus, if the ventilation zone is not occluded, the adsorbent has only a slight effect on the level of the gas phase smoke component and the mainstream smoke flavor.

  In contrast, if the ventilation zone is completely blocked, preventing the inflow of air into the filter and dilution of mainstream smoke, the smoke will cross the adsorbent and certain gas phase smoke components will be adsorbed or The mainstream smoke flow through the filter is altered to be absorbed by the adsorbent. In this case, the adsorption of the smoke component is the main mechanism for reducing the level of the smoke component in the mainstream smoke.

  In some cases, when the ventilation zone is partially blocked, the reduction of smoke components in the mainstream smoke is provided by both mainstream smoke dilution and adsorbent. The composition of the adsorbent and the ventilation zone is such that the reduction of the gas phase smoke component by dilution and the reduction of the same gas phase smoke component by the adsorbent are balanced, and this balance is such that the ventilation zone is blocked. It changes automatically according to. When the dilution level decreases as a result of the ventilation zone being blocked, the adsorption of the smoke component by the adsorbent increases to compensate for the decrease in dilution. Thus, the overall level of smoke components can be kept as small as possible, regardless of whether the ventilation zone is unoccupied, partially occluded or fully occluded. it can.

  The balance between the mainstream smoke dilution level obtained in the ventilation zone and the mainstream smoke component adsorption level by the adsorbent at the surface of the filter wrapper is not limited, but will be described in detail below. It can be controlled by adjusting the parameters of the filter, including the positioning and distribution of the ventilation zone, the dilution level obtained by the ventilation zone, the positioning, distribution and total amount of adsorbent provided. For example, the total amount and location of the ventilation zone, and the total amount and location of the adsorbent can be adjusted so that the delivery of the gas phase smoke component is the same regardless of whether the ventilation zone is blocked or not.

  In the filter of a smoking article according to the present invention, the ventilation zone can be provided on most or all upstream of the adsorbent. With this arrangement, the mainstream smoke flow in the filter varies depending on how much air is drawn from the vent zone through the filter. In the unoccluded state of the ventilation zone, typically the aerated air will be drawn through the filter on the outer surface of the filter material and will direct the mainstream smoke stream toward the center of the filter. Thus, air drawn through the ventilation zone forms an outer concentric layer that shields mainstream smoke away from the adsorbent contained in the filter wrapper. In this way, the smoke does not come into significant contact with the adsorbent. Accordingly, the effect of the adsorbent on mainstream smoke during normal smoking of smoking articles is minimal.

  Aeration is “upstream” of the adsorbent, meaning that aeration is provided at the mouth end of the smoking article farther than the adsorbent. During smoking, mainstream smoke is drawn through the smoking article from the upstream end adjacent to the burning end of the tobacco rod to the downstream end at the mouth end of the filter. Thus, the mainstream smoke will first pass through the ventilation zone and then reach the filter wrapper adsorbent.

  Preferably, the vent zone is in the form of one or more perforations extending circumferentially around the filter. In certain embodiments, multiple rows of perforations can be provided along the filter, for example, at locations spaced from one another by at least 5 mm or at least 10 mm. This configuration means that when smoking, the air flows into the filter from different locations and helps maintain a consistent air layer between the mainstream smoke and the adsorbent along the entire length of the adsorbent. . In this case, the most upstream vent zone can be upstream of all or most of the adsorbent.

  If the ventilation zone is blocked, the amount of air flowing into the filter will decrease, and if the ventilation zone is completely blocked, no air will flow into the filter. Since there is no air layer facing the outside of the filter, the mainstream smoke is no longer confined to the center of the filter and the smoke passing outside the filter comes into contact with the adsorbent contained in the filter wrapper. As the amount of air drawn through the filter decreases, the amount of mainstream smoke that comes into contact with the adsorbent increases and the adsorbent removes a greater amount of smoke components.

  If the ventilation zone is partially occluded, the air and smoke flow through the filter should be a combination of two flow patterns depending on the relative position and occlusion range of the occluded ventilation zone on the filter. . For example, if a portion of the ventilation zone toward the mouth end of the filter is blocked, but the upstream ventilation zone is still not blocked, the mainstream smoke is initially separated from the adsorbent by an air layer outside the filter. The ventilation air and smoke mix towards the mouth end of the filter and more smoke comes into contact with the adsorbent. Preferably, the ventilation zone allows for 10% to 80% dilution of mainstream smoke, and “dilution” is included in the smoke delivered to the consumer from the mouth end of the filter with the ventilation zone unoccupied at all. Refers to the percent by weight of air that is generated In particular, the aeration zone allows 30% to 70% mainstream smoke dilution, more particularly 50% to 80%. The aeration or dilution level obtained in the aeration zone can be determined using ISO test method 9512: 2002.

  The ventilation level can be conveniently adjusted to control the thickness of the concentric air layer that flows through the outer concentric region of the filter and separates mainstream smoke from the adsorbent. When the air layer outside the filter becomes thicker, the effect of the air layer shielding mainstream smoke from the adsorbent increases. Also, if the smoker is smoked when the ventilation zone is not occluded, the effect of the adsorbent on the flavor of smoke delivered to the consumer will be reduced. As another alternative, set the ventilation level through the ventilation zone and adjust the amount of adsorbent so that the delivery of the gas phase smoke component is the same regardless of whether the ventilation zone is blocked or not can do.

  Preferably, the most upstream part of the ventilation zone is provided between 20 mm and 30 mm from the mouth end of the smoking article. Preferably, the most upstream part of the ventilation zone is provided at least 2 mm from the end of the filter rod where the filter abuts the tobacco rod. This positioning of the ventilation zone away from the mouth end of the filter and facing the tobacco rod advantageously increases the available area where the adsorbent can be located downstream of the ventilation zone.

  The ventilation zone is provided upstream of the entire adsorbent or substantially the entire adsorbent. Preferably, the ventilation zone is provided upstream of the entire adsorbent, but those skilled in the art will appreciate that the desired effect of the present invention is that a portion is provided at the location of the ventilation zone or upstream of the ventilation zone. However, it should be understood that the majority of the adsorbent is obtained when it is downstream of the aeration zone. Preferably, the vent zone is provided upstream by at least 80% of the adsorbent.

  The adsorbent can be any suitable adsorbent or absorbent. Various adsorbents for use in smoking articles are known to those skilled in the art. Suitable adsorbents can include, but are not limited to, activated carbon, zeolite, sepiolite, alumina, molecular sieve, and combinations thereof. In certain preferred embodiments, the adsorbent is activated carbon.

  In a preferred embodiment, the filter wrapper of the smoking article of the present invention includes an adsorption layer applied over the filter wrapper surface area. Preferably, the amount of adsorbent in the adsorption layer is at least 20 mg. The amount of adsorbent is preferably up to about 120 mg, more preferably up to about 100 mg, and even more preferably up to about 60 mg. Particularly preferably, the amount of adsorbent is from about 20 mg to about 120 mg, more preferably from about 40 mg to about 60 mg.

  The adsorbent is preferably in the form of a particulate or particulate adsorbent, which is preferably applied to an adhesive layer or binder on the filter wrapper surface. In other embodiments, the adsorbent can be provided as a separate layer disposed on the surface of the filter wrapper. In yet another embodiment, the adsorbent can be applied as a separate layer on the outer surface of the filter segment, and the filter wrapper is wrapped over the adsorbent layer so that the surface of the filter wrapper is in contact with the adsorbent. To be able to.

  As an additional or alternative method of providing an adsorbent within a layer on the filter wrapper surface, the adsorbent can be incorporated on the outer surface of the filter material itself. For example, if the filter comprises a rod of fiber filter material such as cellulose acetate tow, particulate adsorbent can be provided in the concentric outer layer of the filter tow, for example, the thickness of the concentric outer layer is less than 1 mm. The adsorbent can be uniformly provided on the concentric outer layer of the filter tow, or can be a concentric adsorbent gradient in the filter where the proportion of adsorbent in the filter tow increases toward the outside of the filter.

  As an additional or alternative to the construction of the adsorbent described above, the adsorbent can be incorporated into the sheet material that forms the filter wrapper, for example, the adsorbent can be incorporated into the paper material during the manufacture of the material.

  When the adsorbent is on the filter wrapper surface, the adsorbent preferably covers at least 50%, more preferably at least 60% of the outer or inner surface of the filter wrapper. The adsorbent can be provided in a single region on the filter wrapper surface, for example in the form of a pattern applied to the filter wrapper surface, or in multiple regions.

  The adsorbent is preferably provided on the inner surface of the filter wrapper, and “inner surface” refers to the radially inner surface of the wrapper closest to the filter segment. However, in certain other embodiments, if the mainstream smoke is still in contact with the adsorbent during smoking, the adsorbent may be provided on the outer surface of the wrapper in addition to or instead of the inner surface adsorbent. Will be effective. For example, if the filter wrapper is highly porous or air permeable, the adsorbent will be on either the inner surface or the outer surface or both, as the mainstream smoke will contact both surfaces during smoking. Can be provided.

  In certain preferred embodiments of the invention, the filter wrapper on which the adsorbent is applied is a plug wrap that surrounds at least a portion of the filter. The adsorbent can be applied to the inner layer of the plug wrap and its inner surface is in contact with the lower filter material.

  In some cases, the filter is wrapped with a second layer of plug wrap, for example, a layer of plug wrap that joins different segments of a multi-component filter. As an alternative or in addition to the plug wrap inner layer adsorbent, the adsorbent may be applied to a second layer of this plug wrap that covers one or more inner layers of the air permeable plug wrap. it can. The adsorbent can be applied to the inner surface area of the second layer of the plug wrap. Alternatively or additionally, the second layer of plug wrap is substantially air permeable sheet material, in particular so that mainstream smoke easily permeates through the second layer of plug wrap and contacts the adsorbent. The adsorbent can be applied to the outer surface of the second layer of plug wrap.

  In another preferred embodiment of the invention, the filter wrapper on which the adsorbent is applied is a chipping wrapper, such as a chipping paper that surrounds the filter and connects the filter to the tobacco rod. When the adsorbent is provided on the chipping wrapper, the adsorbent needs to be applied to the inner surface of the chipping wrapper so as not to be exposed to the outside of the filter.

  The filter of the smoking article of the present invention can include a single filter segment. Alternatively, the filter can comprise two or more filter segments that are axially aligned with each other. The one or more filter segments can take a variety of forms and suitable filter segments will be known to those skilled in the art. Where two or more filter segments are included, the filter segments can be the same structure and material as each other, can be different structures, or can include different filter materials or additives. Preferably, each of the one or more filter segments forms a plug of fiber filter material, such as cellulose acetate tow or paper wrapped with plug wrap.

  One or more of the filter segments can include particulate material. Preferably, the particulate material is incorporated into the upstream filter segment, eg, at the rod end of the filter segment.

  The particulate material can be dispersed in a plug of fiber filter material such as cellulose acetate or paper. The filter plasticizer can be applied to the fiber filter material in a conventional manner, preferably by spraying the particulate material onto the separated fibers prior to application to the filter material. Alternatively or additionally, the filter can include a filter segment having a hollow cavity at least partially filled with particulate material. In this case, the hollow cavity is preferably provided between two plugs of filter material.

  The particulate material incorporated in the filter can include at least one adsorbent for encapsulation in the filter wrapper described above. When incorporating an adsorbent into a filter, the amount of adsorbent in the filter must be less than the amount of adsorbent contained in the filter wrapper so that the performance characteristics of the filter can be maintained.

  Alternatively or additionally, the particulate material incorporated into the filter may comprise at least one flavor material. For example, the particulate material can include a cellulose material filled with adsorbent particles or a liquid flavor substance such as menthol. Alternatively, the particulate material can include particles of plant material. The plant material can be in the form of plant leaves as disclosed in European Patent 1,958,523. For example, the filter segment can include leaves from tobacco, green tea, mint, peppermint or spearmint, laurels, eucalyptus, basil, sage, verbena, and tarragon. Alternatively, the plant material can be in the form of seeds, rhizomes, bark, or flowers used as a spice.

  Alternatively, one or more of the filter segments can have a liquid flavor substance applied directly to a filter material such as menthol.

  Preferably, the overall length of the smoking article according to the present invention is from 70 mm to about 128 mm, for example about 84 mm.

  Preferably, the outer diameter of the smoking article according to the present invention is from about 5 mm to about 8.5 mm, more preferably about 7.9 mm.

  Preferably, the outer diameter of the filter of the smoking article according to the present invention is from about 18 mm to about 36 mm, more preferably about 27 mm.

  The smoking article of the present invention comprises a rod of tobacco material that is attached to the filter by a chipping wrapper. The rod of tobacco material can include cut tobacco selected from one or more of tobacco leaf, expanded tobacco, reconstituted tobacco, or combinations thereof.

  The invention will now be described in more detail by way of example with reference to the accompanying drawings.

FIG. 2 is a perspective view of a smoking article according to the present invention, with no filter packaged. FIG. 2 is a side view of the smoking article of FIG. 1 schematically illustrating the flow of air and smoke through the filter when the ventilation zone is not blocked. FIG. 2 is a side view of the smoking article of FIG. 1 schematically illustrating the flow of smoke through the filter when the ventilation zone is completely occluded.

  A filter cigarette 10 shown in FIG. 1 includes a packaged tobacco cut filler rod 12 that is axially aligned and attached to a filter 14. The tobacco rod 12 is packaged with cigarette paper (not shown). The filter 14 comprises a single segment 16 in the form of a plug of cellulose acetate tow. The filter segment 16 is packaged with a plug wrap 18 that surrounds the entire length of the filter 14.

  The plug wrap 18 is in the form of a sheet of air permeable paper and includes an adsorption layer 20 that covers an area corresponding to about 50% of the inner surface of the plug wrap 18. The adsorption layer 20 is a layer in which about 50 mg of particulate activated carbon attached to the inner surface of the plug wrap 18 with a suitable adhesive is substantially uniformly dispersed. In the assembled filter, the adsorption layer 20 extends circumferentially around the filter segment 16 and contacts the outer surface of the filter segment 16.

  The packaged tobacco rod 12 and the packaged filter 14 are connected to each other by an outer chipping wrapper 22 that surrounds the entire length of the filter 14 and the adjacent portion of the tobacco rod 12 and covers the plug wrap 16. The chipping wrapper 22 is in the form of a chipping paper and is formed with a vent zone comprising a row of perforations 24 extending around the filter 14. A row of perforations 24 is disposed on the filter at the rod end of the filter segment 16 adjacent to the interface between the filter 14 and the tobacco rod 12. The entire area of the adsorption layer 20 is downstream of the row of perforations 24. In the unperforated state of the perforations, the ventilation zone allows about 60% dilution of mainstream smoke when smoking.

  During normal smoking of the filter cigarette 10, the perforations are not completely covered, and air flows into the filter 14 through the perforations in the chipping wrapper 22, as schematically shown in FIG. In FIG. 2, the air flow is indicated by a white arrow, and the mainstream smoke flow is indicated by a shaded arrow. As shown, air will be drawn through the filter 14 toward the mouth end of the filter 14, forming a concentric air layer 26 around the outside of the filter segment 16. The mainstream smoke is drawn from the tobacco rod and the mainstream smoke is pumped toward the center of the filter segment 16 due to the presence of the air layer 26, so that the mainstream smoke is separated from the inner surface of the plug wrap 18 by the air layer 26. This means that during smoking when the perforations 24 are not completely occluded, contact between the mainstream smoke and the activated carbon of the adsorption layer 20 on the inner surface of the plug wrap 18 will be limited. . Therefore, the presence of the adsorption layer 20 has a slight effect on the gas phase component level of the mainstream smoke. However, the air flowing into the filter 14 can dilute mainstream smoke, so that the smoke vapor phase component level experienced by the consumer will be reduced by about 60%.

  The position of the row of perforations 24 upstream of the entire adsorbent layer 20 is such that the mainstream smoke moves away from the outside of the filter segment 16 toward the center of the filter before it reaches the part of the filter segment where the adsorbent layer 20 begins. Guarantee.

  FIG. 3 shows a state in which all the perforations 24 are completely covered, and no air flows into the filter 14 when smoking. In this state, the mainstream smoke is not diluted in the filter, so the gas phase component is not reduced as a result of the aeration zone. As indicated schematically by the shaded arrows in FIG. 3, because there is no air layer 26, mainstream smoke is not constrained to the center of the filter segment 16 and can be drawn through all cross sections of the filter segment 16. Thus, unlike the situation of FIG. 2, the mainstream smoke will come into contact with the adsorption layer 20 on the inner surface of the plug wrap 18 as the smoke is drawn through the filter 14. Because the activated carbon of the adsorption layer 20 adsorbs certain gas phase components from mainstream smoke, the overall level of these components in the smoke delivered to the consumer is reduced.

The level of the gas phase component (carbonyl compound) in the mainstream smoke in the state shown in FIG. 3 is within a range of up to 40% of the level of the same gas phase component as a result of dilution in the state shown in FIG.

  In fact, when smoking, it is unlikely that the consumer will completely block all the perforations 24 of the tipping paper 22, so the situation shown in FIG. 3 is the result of an experimental Health Canada smoking test. Only likely to be brought. However, since the consumer may accidentally plug some of the perforations 24 by placing a finger around the filter in the region of the ventilation zone, air flows into the filter 14 through the perforations covered with fingers. Can not do it. In this case, the situation is between the two embodiments of FIGS. 2 and 3, the air layer 26 does not spread all around the filter 14, and the mainstream smoke flows in contact with the adsorbing layer 20 at a specific location. It will be.

Partially plugging the perforations 24 will reduce the amount of air entering the filter 14 and will reduce the dilution of mainstream smoke as well, thus reducing the level of gas phase components due to dilution. . However, due to the contact of the mainstream smoke adsorption layer 20 with the activated carbon, the reduction of the gas phase component due to the adsorbent increases, so that the overall level of the gas phase component is still the maximum level in the state shown in FIGS. It is within the range of 40%.

  Thus, as a result of the combination of the dilution and adsorption layer 20, the mainstream smoke gas phase component level is compared to whether the perforations 24 are not plugged, partially plugged, or completely plugged. It should be understood that it is not affected.

  In the embodiment described and illustrated above, an adsorbing layer is provided on the inner surface of the plug wrap, but the plug wrap and / or chipping has the same effect on reducing the mainstream smoke gas phase component. It should be understood that other configurations of the adsorption layer on the wrapper are possible.

DESCRIPTION OF SYMBOLS 10 Filter cigarette 12 Cigarette cut filler rod 14 Filter 16 Filter segment 18 Plug wrap 20 Adsorption layer 22 Chipping paper 24 Perforation

Claims (11)

Tobacco rod,
A filter comprising one or more filter segments connected to the tobacco rod and surrounded by a filter wrapper comprising a layer of adsorbent, wherein the layer of adsorbent is applied on a surface area of the filter wrapper. And the filter extending circumferentially around the filter ;
With
The filter includes a ventilation zone provided on the upstream side of the adsorbent,
The ventilation zone can be diluted from 30% to 70% when the ventilation zone is not blocked at all;
The ventilation zone is provided on all upstream sides of the adsorbent,
The ventilation zone is between 20 mm and 30 mm from the mouth end of the smoking article;
Air drawn through the vent zone forms an outer concentric layer that shields mainstream smoke from the adsorbent contained in the filter wrapper, and when the vent zone is not blocked, When the ventilation zone is blocked by dilution, the mainstream gas phase smoke component is absorbed by the adsorbent, and when the ventilation zone is partially blocked by both the dilution and the adsorbent. Smoking articles that reduce levels . The smoking article of claim 1 , wherein the ventilation zone includes one or more rows of perforations extending circumferentially around the filter. The smoking article of claim 2 , wherein the rows of perforations are spaced apart from each other by at least 5 mm. The smoking article according to any one of claims 1 to 3 , wherein the filter wrapper is a plug wrap or a chipping wrapper. The smoking article according to any one of claims 1 to 4 , wherein the filter wrapper includes an adsorption layer applied to at least a part of an inner surface of the filter wrapper. The smoking article according to any one of claims 1 to 4 , wherein the filter wrapper is substantially air permeable, and an adsorption layer is applied to at least a part of an outer surface of the filter wrapper. The smoking article of claim 5 or 6 , wherein the filter wrapper comprises between about 40 mg and about 60 mg of adsorbent. The smoking article according to any one of claims 1 to 7 , wherein the adsorbent covers at least 60% of one of the inner surface and the outer surface of the filter wrapper. The smoking article according to any one of claims 1 to 8 , wherein the adsorbent includes a particulate adsorbent applied to an adhesive layer on a surface of the filter wrapper. The smoking article according to any one of claims 1 to 9 , wherein the adsorbent includes a particulate adsorbent incorporated into the filter wrapper. The filter includes one or more segments of fibrous filter material, smoking articles according to any one of claims 1 to 10.

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