AEROSOL-GENERATING ARTICLE WITH NON-CIRCULAR PERFORATIONS IN A VENTILATION ZONE

Abstract

An aerosol-generating article is provided, including: a rod of aerosol-generating substrate; and a ventilation zone arranged downstream the rod, the ventilation zone being configured as a hollow tubular ventilation zone and including perforations, one or more of the perforations has a non-circular cross-section having an ovality of at least 1.5, the ovality being a ratio of a large diameter of a perforation divided by a small diameter of the perforation, a thickness of a peripheral wall of the ventilation zone being between 0.1 millimeter and 2.5 millimeters, the one or more perforations having a width of between 0.05 millimeter and 0.2 millimeter, and the one or more perforations having a length of between 0.25 millimeter and 1.0 millimeter. An aerosol-generating system including an aerosol-generating device having a cavity configured to receive the aerosol-generating article is also provided. A method for manufacturing the aerosol-generating article is also provided.

Claims

1.-14. (canceled)

15. An aerosol-generating article, comprising: a rod of aerosol-generating substrate; and a ventilation zone arranged downstream the rod of aerosol-generating substrate, wherein the ventilation zone is configured as a hollow tubular ventilation zone, wherein the ventilation zone comprises perforations, wherein one or more of the perforations has a non-circular cross-section having an ovality of at least 1.5, the ovality being a ratio of a large diameter of a perforation divided by a small diameter of the perforation, wherein a thickness of a peripheral wall of the ventilation zone is between 0.1 millimeter and 2.5 millimeters, wherein the one or more perforations has a width of between 0.05 millimeter and 0.2 millimeter, and wherein the one or more perforations has a length of between 0.25 millimeter and 1.0 millimeter.

16. The aerosol-generating article according to claim 15, wherein the one or more perforations has a width of between 0.11 millimeter and 0.13 millimeter.

17. The aerosol-generating article according to claim 16, wherein the one or more perforations has a length of between 0.5 millimeter and 0.6 millimeter.

18. The aerosol-generating article according to claim 15, wherein the one or more of the perforations has an oval cross-section.

19. The aerosol-generating article according to claim 15, wherein the one or more of the perforations is slit-shaped.

20. The aerosol-generating article according to claim 15, wherein for one or more of the perforations, the length of the perforations is larger than the width of the perforations.

21. The aerosol-generating article according to claim 15, wherein for one or more of the perforations, a longitudinal axis of the perforation is parallel to a longitudinal axis of the aerosol-generating article.

22. The aerosol-generating article according to claim 15, wherein the ovality of the perforations is at least 2.

23. The aerosol-generating article according to claim 15, wherein an inner diameter of the hollow tubular ventilation zone is between 2.5 millimeters and 5.0 millimeters.

24. The aerosol-generating article according to claim 15, wherein an inner diameter of the hollow tubular ventilation zone is 3.3 millimeters.

25. The aerosol-generating article according to claim 15, wherein the ventilation zone is arranged in a hollow tubular segment of an aerosol-cooling element, and wherein the hollow tubular segment has an inner volume of between 130 mm.sup.3 and 200 mm.sup.3.

26. The aerosol-generating article according to claim 15, wherein the ventilation zone is arranged in a hollow tubular segment of an aerosol-cooling element, and wherein the hollow tubular segment has an inner volume of 170 mm.sup.3.

27. The aerosol-generating article according to claim 15, wherein a distance between the perforations of the ventilation zone and a downstream end of the rod of aerosol-generating substrate is between 1 millimeter and 6 millimeters.

28. The aerosol-generating article according to claim 15, wherein a distance between the perforations of the ventilation zone and a downstream end of the aerosol-generating article is between 10 millimeters and 26 millimeters.

29. The aerosol-generating article according to claim 15, wherein the perforations are configured to allow ambient air to be drawn into the ventilation zone.

30. The aerosol-generating article according to claim 29, wherein a ratio of ambient air drawn into the ventilation zone through the perforations and air drawn into the ventilation zone through the rod of aerosol-forming substrate is between 5 percent and 75 percent.

31. The aerosol-generating article according to claim 15, further comprising a filter plug downstream of the ventilation zone, wherein a resistance-to-draw of the filter plug is between 5 millimeters H.sub.2O and 80 millimeters H.sub.2O.

32. The aerosol-generating article according to claim 15, further comprising a substrate wrapper at least partly circumscribing the rod of aerosol-forming substrate, wherein the substrate wrapper has a thickness of 50 micrometers or more.

33. An aerosol-generating system comprising an aerosol-generating device having a cavity configured to receive the aerosol-generating article according to claim 15.

34. A method for manufacturing an aerosol-generating article, the method comprising the steps of: providing a rod of aerosol-generating substrate; providing a ventilation zone downstream of the rod of the aerosol-generating substrate, wherein the ventilation zone is configured as a hollow tubular ventilation zone; and creating non-circular perforations in a peripheral wall of the ventilation zone having an ovality of at least 1.5, the ovality being a ratio of a large diameter of a perforation divided by a small diameter of the perforation, wherein a thickness of the peripheral wall of the ventilation zone is between 0.1 millimeter and 2.5 millimeters, wherein one or more perforations has a width of between 0.05 millimeter and 0.2 millimeter, and wherein one or more perforations have a length of between 0.25 millimeter and 1.0 millimeter.

Description

[0293] In the following, the invention will be further described with reference to

[0294] FIG. 1, which shows a schematic side sectional view of an aerosol-generating article in accordance with the invention;

[0295] FIG. 2, which shows a cross-sectional view of the aerosol-generating article in the position of a ventilation zone; and

[0296] FIG. 3, which shows a non-circular perforation in the ventilation zone.

[0297] The aerosol-generating article 10 shown in FIG. 1 comprises a rod 12 of aerosol-forming substrate 12 and a downstream section 14 at a location downstream of the rod 12 of aerosol-forming substrate. Further, the aerosol-generating article 10 comprises an upstream section 16 at a location upstream of the rod 12 of aerosol-forming substrate. Thus, the aerosol-generating article 10 extends from an upstream or distal end 18 to a downstream or mouth end 20.

[0298] The aerosol-generating article has an overall length of about 45 millimetres.

[0299] The downstream section 14 comprises a support element 22 located immediately downstream of the rod 12 of aerosol-forming substrate, the support element 22 being in longitudinal alignment with the rod 12. In the embodiment of FIG. 1, the upstream end of the support element 18 abuts the downstream end of the rod 12 of aerosol-forming substrate. In addition, the downstream section 14 comprises an aerosol-cooling element 24 located immediately downstream of the support element 22, the aerosol-cooling element 24 being in longitudinal alignment with the rod 12 and the support element 22. In the embodiment of FIG. 1, the upstream end of the aerosol-cooling element 24 abuts the downstream end of the support element 22.

[0300] As will become apparent from the following description, the support element 22 and the aerosol-cooling element 24 together define an intermediate hollow section 50 of the aerosol-generating article 10. As a whole, the intermediate hollow section 50 does not substantially contribute to the overall RTD of the aerosol-generating article. An RTD of the intermediate hollow section 26 as a whole is substantially 0 millimetres H.sub.2O.

[0301] The support element 22 comprises a first hollow tubular segment 26. The first hollow tubular segment 26 is provided in the form of a hollow cylindrical tube made of cellulose acetate. The first hollow tubular segment 26 defines an internal cavity 28 that extends all the way from an upstream end 30 of the first hollow tubular segment to a downstream end 32 of the first hollow tubular segment 20. The internal cavity 28 is substantially empty, and so substantially unrestricted airflow is enabled along the internal cavity 28. The first hollow tubular segment 26and, as a consequence, the support element 22does not substantially contribute to the overall RTD of the aerosol-generating article 10. In more detail, the RTD of the first hollow tubular segment 26 (which is essentially the RTD of the support element 22) is substantially 0 millimetres H.sub.2O.

[0302] The first hollow tubular segment 26 has a length of about 8 millimetres, an external diameter of about 7.25 millimetres, and an internal diameter (D.sub.FTS) of about 1.9 millimetres. Thus, a thickness of a peripheral wall of the first hollow tubular segment 26 is about 2.67 millimetres.

[0303] The aerosol-cooling element 24 comprises a second hollow tubular segment 34. The second hollow tubular segment 34 is provided in the form of a hollow cylindrical tube made of cellulose acetate. The second hollow tubular segment 34 defines an internal cavity 36 that extends all the way from an upstream end 38 of the second hollow tubular segment to a downstream end 40 of the second hollow tubular segment 34. The internal cavity 36 is substantially empty, and so substantially unrestricted airflow is enabled along the internal cavity 36. The second hollow tubular segment 28and, as a consequence, the aerosol-cooling element 24does not substantially contribute to the overall RTD of the aerosol-generating article 10. In more detail, the RTD of the second hollow tubular segment 34 (which is essentially the RTD of the aerosol-cooling element 24) is substantially 0 millimetres H.sub.2O. The second hollow tubular segment 34 has a length of about 8 millimetres, an external diameter of about 7.25 millimetres, and an internal diameter (D.sub.STS) of about 3.25 millimetres. Thus, a thickness of a peripheral wall of the second hollow tubular segment 34 is about 2 millimetres. Thus, a ratio between the internal diameter (D.sub.FTS) of the first hollow tubular segment 26 and the internal diameter (D.sub.STS) of the second hollow tubular segment 34 is about 0.75.

[0304] The aerosol-generating article 10 comprises a ventilation zone 60 provided at a location along the second hollow tubular segment 34. In more detail, the ventilation zone is provided at about 2 millimetres from the upstream end of the second hollow tubular segment 34. A ventilation level of the aerosol-generating article 10 is about 25 percent.

[0305] In the embodiment of FIG. 1, the downstream section 14 further comprises a mouthpiece element 42 at a location downstream of the intermediate hollow section 50. In more detail, the mouthpiece element 42 is positioned immediately downstream of the aerosol-cooling element 24. As shown in the drawing of FIG. 1, an upstream end of the mouthpiece element 42 abuts the downstream end 40 of the aerosol-cooling element 18.

[0306] The mouthpiece element 42 is provided in the form of a cylindrical plug of low-density cellulose acetate.

[0307] The mouthpiece element 42 has a length of about 12 millimetres and an external diameter of about 7.25 millimetres. The RTD of the mouthpiece element 42 is about 12 millimetres H.sub.2O.

[0308] The rod 12 comprises an aerosol-forming substrate of one of the types described above.

[0309] The rod 12 of aerosol-forming substrate has an external diameter of about 7.25 millimetres and a length of about 12 millimetres.

[0310] The aerosol-generating article 10 further comprises an elongate susceptor 44 within the rod 12 of aerosol-forming substrate. In more detail, the susceptor 44 is arranged substantially longitudinally within the aerosol-forming substrate, such as to be approximately parallel to the longitudinal direction of the rod 12. As shown in the drawing of FIG. 1, the susceptor 44 is positioned in a radially central position within the rod and extends effectively along the longitudinal axis of the rod 12.

[0311] The susceptor 44 extends all the way from an upstream end to a downstream end of the rod 12. In effect, the susceptor 44 has substantially the same length as the rod 12 of aerosol-forming substrate.

[0312] In the embodiment of FIG. 1, the susceptor 44 is provided in the form of a strip and has a length of about 12 millimetres, a thickness of about 60 micrometres, and a width of about 4 millimetres. The upstream section 16 comprises an upstream element 46 located immediately upstream of the rod 12 of aerosol-forming substrate, the upstream element 46 being in longitudinal alignment with the rod 12. In the embodiment of FIG. 1, the downstream end of the upstream element 46 abuts the upstream end of the rod 12 of aerosol-forming substrate. This advantageously prevents the susceptor 44 from being dislodged. Further, this ensures that the consumer cannot accidentally contact the heated susceptor 44 after use.

[0313] The upstream element 46 is provided in the form of a cylindrical plug of cellulose acetate circumscribed by a stiff wrapper. The upstream element 46 has a length of about 5 millimetres. The RTD of the upstream element 46 is about 30 millimetres H.sub.2O.

[0314] FIG. 2 shows the perforations 62 at the ventilation zone 60. The ventilation zone 60 is provided at a location along the second hollow tubular segment 34. The perforations 62 are arranged in the peripheral wall of the hollow tubular segment 34. The perforations 62 are arranged in a row around the peripheral wall of the hollow tubular segment 34. The perforations 62 are configured to allow ambient air to flow into the internal cavity 36. FIG. 2 shows that 11 perforations are provided in the peripheral wall of the hollow tubular segment 34. This number of perforations 62 has been found to be particularly beneficial for aerosol creation.

[0315] FIG. 3 shows a non-circular perforation 62. The perforation 62 has an ovality with a length L that is substantially larger than the width W of the perforation 62. The length of the perforation 62 extends parallel to the central axis of the aerosol-generating article.

[0316] Features described in relation to one embodiment may equally be applied to other embodiments of the invention.