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A cigarette comprises a tobacco rod and a multi-component filter comprising a bed of adsorbent and a flavor-releasing filter segment located downstream of the bed of adsorbent. In the preferred embodiment, the adsorbent is also flavor-bearing and comprises high surface area, activated carbon. As mai

A cigarette comprises a tobacco rod and a multi-component filter comprising a bed of adsorbent and a flavor-releasing filter segment located downstream of the bed of adsorbent. In the preferred embodiment, the adsorbent is also flavor-bearing and comprises high surface area, activated carbon. As mainstream smoke is drawn through the upstream portion of the filter, gas phase smoke constituents are removed and flavor is released from the adsorbent bed. Thereafter additional flavor is released into the mainstream smoke as it passes through the flavor-releasing filter segment. Ventilation is provided to limit the amount of tobacco being combusted during each puff and is arranged at a location spaced downstream from the adsorbent bed to lower mainstream smoke velocity through the adsorbent bed. Preferably, the carbon bed comprises at least 90 to 120 mg or greater of carbon in a fully filled condition or 160 to 180 mg or greater of carbon in a 85 filled condition or better, which in combination with other features provides a flavorful cigarette that achieves significant reductions in gas phase constituents of the mainstream smoke, including 90% reductions or greater in 1, 3 butadiene, acrolein, isoprene, propionaldehyde, acrylonitrile, benzene, toluene, styrene, and 80% reductions or greater in acetaldehyde and hydrogen cyanide.

대표청구항 ▼

1. A cigarette comprising a tobacco rod and a multi-component filter comprising a bed of adsorbent particles and ventilation at a location downstream of said bed of adsorbent particles, said bed of adsorbent particles and ventilation constructed and arranged to substantially remove of at least one s

1. A cigarette comprising a tobacco rod and a multi-component filter comprising a bed of adsorbent particles and ventilation at a location downstream of said bed of adsorbent particles, said bed of adsorbent particles and ventilation constructed and arranged to substantially remove of at least one smoke constituent from mainstream tobacco smoke as mainstream smoke is drawn through the filter, and at least one flavor-releasing component constructed and arranged to release flavor to mainstream smoke, the flavor-releasing filter component being located downstream of the said bed of adsorbent particles in a direction of mainstream smoke drawn through the filter. 2. The cigarette as in claim 1, wherein said bed of adsorbent particles includes a flavorant-bearing, activated carbon. 3. The cigarette as in claim 2, wherein the flavor-releasing component includes a cellulose acetate plug with flavorant thereon. 4. The cigarette as in claim 2, wherein the flavor-releasing component includes a cellulose acetate plug surrounded by plug wrap with flavorant on the plug wrap. 5. The cigarette as in claim 2, wherein the flavor-releasing filter component includes a flavorant-bearing filament and surrounding cellulose located downstream of said flavorant-bearing, activated carbon. 6. The cigarette as in claim 5, wherein said bed of adsorbent particles is disposed in a cavity defined between a tobacco end filter component and a central filter component, said cavity in a condition of being at least 85% filled. 7. The cigarette as claimed in claim 6, wherein said tobacco end filter component is located adjacent said tobacco rod, and said central filter component having an end portion adjacent said bed of adsorbent particles, said ventilation at a location along said adjacent upstream end portion of said central filter component. 8. The cigarette as in claim 7, wherein said ventilation is in the range of 45 to 55%, and wherein said multi-component filter further comprises a mouth end filter component downstream of said central filter component. 9. The cigarette as in claim 8, wherein said tobacco end filter segment, said central fitter component, said bed of adsorbent particles and said mouth end filter component are of low particulate filtration efficiency. 10. The cigarette as in claim 9, wherein the level of resistance to draw of said mouth end component and said central filter component is greater than the resistance to draw of said tobacco end filter component. 11. The cigarette as in claim 10, wherein said ventilation comprises a circumferential row of perforations through a tipping paper, said tipping paper attaching said multi-component filter to said tobacco filter rod. 12. The cigarette as in claim 11, wherein said ventilation is located at least 12 mm from a buccal end of the cigarette. 13. The cigarette as in claim 5, wherein the bed of adsorbent particles comprises activated carbon of at least 90 mg in a fully filled condition. 14. The cigarette as in claim 5, wherein the bed of adsorbent particles comprises a high surface area activated carbon; at least 90 to 120 mg or greater of said carbon in a fully filled condition or 160 to 180 mg or greater of said carbon in a 85% filled condition or better. 15. The cigarette as in claim 5, wherein the bed of adsorbent particles comprises a high surface area activated carbon of at least 90 to 120 mg in fully filled condition. 16. The cigarette as in claim 1, wherein the multi-component filter includes a component in the form of a plug defining a flow path with a transition from generally circular to generally annular to thereby produce an increased pressure drop and increased dwell time of mainstream tobacco smoke in the filter. 17. The cigarette as in claim 1, wherein the multi-component filter includes a component in the form of a plug providing a flow constriction downstream of the bed of adsorbent particles. 18. The cigarette as in claim 17, wherein the plug providing the flow constriction downstream of the bed of adsorbent particles defines an annular flow path. 19. The cigarette as in claim 17, wherein the plug providing the flow constriction downstream of the bed of absorbent particles defines a central flow path. 20. The cigarette as in claim 17, wherein the plug providing the flow constriction downstream of the bed of adsorbent particles comprises a concentric filter. 21. A multi-component filter of a smoking article comprising:an absorbent bearing segment adjacent an upstream end portion of the filter, the absorbent bearing segment including a bed of adsorbent particles and having a particulate efficiency in the range 10-20% and a lesser RTD;an RTD-inducing segment including a flow constriction and ventilation, the RTD-inducing segment being located at an intermediate location along said filter, the RTD-inducing segment having a particulate efficiency in the range of 10-20%; anda flavor releasing segment at a downstream location along said filter, said flavor releasing segment having a particulate efficiency in the range 10-20% and a lesser RTD;the lesser RTD being less than an RTD of the RTD inducing segment. 22. The multi-component filter as in claim 21, wherein the ventilation is adjacent an upstream end portion of the RTD-inducing segment. 23. A cigarette comprising a tobacco rod and a multi-component filter comprising at least one adsorbent-bearing flavor-releasing segment including a bed of flavored adsorbent particles constructed and arranged to release flavor into mainstream tobacco smoke and to remove at least one smoke constituent from mainstream tobacco smoke as mainstream smoke is drawn through the filter, and at least one additional flavor-releasing segment constructed and arranged to release added flavor to mainstream smoke, the additional flavor-releasing segment being located downstream of the adsorbent-bearing flavor-releasing segment in a direction of mainstream smoke drawn through the filter. 24. The cigarette as in claim 23, wherein the additional flavor-releasing segment includes yarn with flavorant thereon and surrounding cellulose acetate. 25. The cigarette as in claim 23, wherein the bed of flavored adsorbent particles comprises activated carbon with flavorant on the carbon. 26. The cigarette as in claim 25, wherein the adsorbent-bearing flavor-releasing segment includes three filter components including the activated carbon with flavorant on the carbon and cellulose acetate tow components on opposite sides of the activated carbon. 27. The cigarette as in claim 23, including tipping paper surrounding the multi-component filter, and perforations in the tipping paper downstream from the adsorbent-bearing flavor-releasing segment tar introducing ambient air into mainstream tobacco smoke drawn through the filter. 28. The cigarette as in claim 23, wherein the additional flavor-releasing segment includes a cellulose acetate plug with flavorant thereon. 29. The cigarette as in claim 23, wherein the additional flavor-releasing segment includes a cellulose acetate plug surrounded by plug wrap with flavorant on the plug wrap. 30. The cigarette as in claim 23, wherein the the bed of flavored absorbent particles comprises carbon particles with flavorant on the carbon. 31. The cigarette as in claim 23, wherein the bed of flavored absorbent particles comprises carbon particles with flavorant on the carbon including at least 90 to 120 mg or greater of said carbon in a fully filled condition or 160 to 180 mg or greater of said carbon in a 85% filled condition or better. 32. A cigarette comprising a tobacco rod and a multi-component filter comprising:a bed of adsorbent particles and a flavor-releasing filter segment located downstream of the bed of adsorbent particles, said bed of adsorbent particles being flavor-bearing and comprising high surface area, activated carbon so that as mainstream smoke is drawn through the upstream portion of the filter, gas phase smoke constituents are removed and flav or is released from the bed of adsorbent particles and thereafter additional flavor is released into the mainstream smoke as it passes through the flavor-releasing filter segment;filter ventilation arranged at a location spaced downstream from the adsorbent bed of adsorbent particles so as to lower mainstream smoke velocity through the adsorbent bed; andsaid carbon bed comprising at least 90 to 120 mg or greater of said carbon in a fully filled condition or 160 to 180 mg or greater of said carbon in a 85% filled condition or better,wherein said cigarette achieves a significant reduction in a gas phase constituent of the mainstream smoke. 33. The cigarette as in claim 32, wherein the cigarette achieves significant reductions in gas phase constituents of mainstream smoke, including 90% reductions or greater in at least one of 1, 3 butadiene, acrolein, isoprene, propionaldehyde, acrylonitrile, benzene, toluene and styrene. 34. The cigarette as in claim 32, wherein the cigarette achieves significant reductions in gas phase constituents of the mainstream smoke, including 80% reductions or greater in at least one of acetaldehyde and hydrogen cyanide. 35. A cigarette comprising a tobacco rod and a multi-component filter comprising:a bed of adsorbent particles comprising a high surface area, activated carbon so that as mainstream smoke is drawn through the upstream portion of the filter, gas phase smoke con constituents are removed;filter ventilation arranged at a location spaced downstream from the adsorbent bed of adsorbent particles so as to lower mainstream smoke velocity through the adsorbent bed; andsaid carbon bed comprising at least 90 to 120 mg or greater of said carbon in a fully filled condition or 160 to 180 mg or greater of said carbon in a 85% filled condition or better; andsaid filter ventilation being spaced from a mouth end of said cigarette by at least approximately 12 mm;wherein said cigarette achieves a significant reduction in a gas phase constituent of the mainstream smoke. 36. A multi-component cigarette filter comprising at least one adsorbent-bearing flavor-releasing segment including a bed of flavored adsorbent particles constructed and arranged to release flavor into mainstream tobacco smoke and to remove at least one smoke constituent from mainstream tobacco smoke, end at least one additional flavor-releasing segment constructed and arranged to release added flavor to mainstream smoke, the additional flavor-releasing segment being located downstream of the adsorbent-bearing flavor-releasing. 37. The filter as in claim 36, wherein the additional flavor-releasing segment includes yarn with flavorant thereon and surrounding cellulose acetate. 38. The filter as in claim 36, wherein the bed of flavored adsorbent particles includes activated carbon with flavorant on the carbon. 39. The filter as in claim 38, wherein the adsorbent-bearing flavor-releasing segment includes three filter components including the activated carbon with flavorant on the carbon and cellulose acetate tow components on opposite sides of the activated carbon. 40. The filter as in claim 38, wherein the additional flavor-releasing segment includes a cellulose acetate plug with flavorant thereon. 41. The filter as in claim 36, wherein the additional flavor-releasing segment includes a cellulose acetate plug surrounded by plug wrap with flavorant on the plug wrap. 42. The filter as in claim 36, wherein the bed of flavored adsorbent particles comprises carbon particles with flavorant on the carbon. 43. The filter as in claim 42, wherein the bed of carbon particles includes at least 90 to 120 mg or greater of said carbon in a fully filled condition or 160 to 180 mg or greater of said carbon in a 85% filled condition or better. 44. A cigarette comprising a tobacco rod and a filter, the filter comprising:a first filter plug adjacent the tobacco rod;a second filter plug in a spaced apart and downstream relation to said first filter plug so as to def ine a cavity therebetween, said second filter plug including a flavor-bearing filament and ventilation perforations;a bed of adsorbent particles in the cavity, said adsorbent comprising activated carbon particles in an amount of 160 to 180 mg or greater in the cavity, with said cavity in an 85% filled condition or better, said activated carbon particles being flavor-bearing; anda third, mouth piece filter plug located downstream from said second filter plug, said first, second and third filter plugs being essentially free of carbon particles;wherein said filter removes at least 90% of at least one of 1, 3 butadiene, acrolein, isoprene, propionaldehyde, acrylonitrile, benzene, toluene and styrene from mainstream smoke as the smoke is drawn through said filter, said fitter releasing flavor into mainstream smoke as the smoke is drawn through the bed and the second plug of the filter.