Smoking article with mouth end cavity
A smoking article ( 10 ) comprises a tobacco rod ( 12 ) and a filter ( 14 ) connected to the tobacco rod ( 12 ). The filter ( 14 ) comprises a first filter segment ( 18, 20 ) comprising one or more breakable capsules, wherein each breakable capsule comprises an outer shell and an inner core containing an additive. The filter ( 14 ) further comprises a hollow tube segment ( 22 ) downstream of the first filter segment ( 18, 20 ) and positioned between a downstream end of the first filter segment ( 18, 20 ) and the mouth end of the filter ( 14 ). The hollow tube segment ( 22 ) defines a cavity ( 24 ) at the mouth end of the filter ( 14 ). A plug wrap ( 23 ) circumscribes the first filter segment ( 18, 20 ) and the hollow tube segment ( 22 ), wherein the plug wrap ( 23 ) has a basis weight of less than 90 grams per square meter.
1. A smoking article comprising:
a tobacco rod;
a filter comprising:
a first filter segment comprising one or more breakable capsules, each breakable capsule comprising an outer shell and an inner core containing an additive;
a hollow tube segment downstream of the first filter segment, the hollow tube segment comprising a wall with an inner wall surface defining a cavity at the mouth end of the filter, the hollow tube segment positioned between a downstream end of the first filter segment and the mouth end of the filter; and
a plug wrap circumscribing the first filter segment and an outer wall surface of the hollow tube segment, wherein the plug wrap has a basis weight of less than 90 grams per square meter,
wherein the wall of the hollow tube segment is formed from a plurality of overlapping paper layers, adjacent paper layers of the wall of the hollow tube segment being adhered together by an intermediate layer of an adhesive; and
a tipping wrapper circumscribing the plug wrap and at least a portion of the tobacco rod to connect the filter to the tobacco rod.
2. The smoking article according to claim 1 , wherein the ovality of the hollow tube segment after a 50% deformation of the filter is less than 25%.
3. A smoking article according to claim 2 wherein the ovality of the tube segment is less than 25% after a capsule crush test in which a force corresponding to the crush strength of the one or more capsules is applied to the first filter segment.
4. A smoking article according to claim 1 wherein the ovality of the tube segment is less than 25% after a capsule crush test in which a force corresponding to the crush strength of the one or more capsules is applied to the first filter segment.
5. A smoking article according to claim 1 , wherein the wall of the hollow tube segment is formed from a plurality of spirally wound paper layers.
6. A smoking article according to claim 1 , wherein the difference between the ovality of the tube segment after 50% deformation of the filter and the ovality of the tube segment prior to deformation of the filter is less than 25%.
7. A smoking article according to claim 1 , wherein the ovality of the hollow tube segment after a 50% deformation of the filter performed after the smoking article has been subjected to a smoking test is less than 35%.
8. A smoking article according to claim 1 wherein the hollow tube segment comprises a coating layer on an inner surface thereof.
9. A smoking article according to claim 1 wherein the compressive strength of the filter is at least 20 Newtons at 50% compression.
10. A smoking article according to claim 1 wherein the wall of the hollow tube segment has a thickness of between 150 micrometers and 500 micrometers.
11. A smoking article according to claim 1 wherein the hollow tube segment extends at least 2 mm from the downstream end of the first filter segment.
12. A smoking article according to claim 1 further comprising a rod end segment between the first filter segment and the tobacco rod.
13. A smoking article according to claim 1 , wherein the tipping wrapper comprises paper having a basis weight between about 20 gsm and 70 gsm.