AEROSOL GENERATING ARTICLE WITH HEAT-EXPANDABLE CENTERING ELEMENT

Abstract

An aerosol-generating article for producing an inhalable aerosol when heated is provided, the aerosol-generating article including: a rod of aerosol-generating substrate; a wrapper circumscribing at least the rod; and at least one heat-expandable element disposed on an outer surface of the wrapper. An aerosol-generating system is also provided, including the aerosol aerosol-generating article and an electrically operated aerosol-generating device.

Claims

1.-15. (canceled)

16. An aerosol-generating article for producing an inhalable aerosol when heated, the aerosol-generating article comprising: a rod of aerosol-generating substrate; a wrapper circumscribing at least the rod; and at least one heat-expandable element disposed on an outer surface of the wrapper.

17. The aerosol-generating article according to claim 16, wherein the at least one heat-expandable element comprises a heat-reactive material.

18. The aerosol-generating article according to claim 17, wherein the heat-reactive material is an intumescent reactive material.

19. The aerosol-generating article according to claim 17, wherein upon heating the heat-reactive material expands by at least about 1.1 times.

20. The aerosol-generating article according to claim 16, wherein the at least one heat-expandable element expands by a factor of between about 10 times and about 100 times its original dimensions when exposed to heat.

21. The aerosol-generating article according to claim 16, wherein the at least one heat-expandable element extends about a circumference of the wrapper.

22. The aerosol-generating article according to claim 16, further comprising a plurality of heat-expandable elements disposed at distinct locations about a circumference of the wrapper.

23. The aerosol-generating article according to claim 17, wherein the heat-reactive material is disposed homogenously about a circumference of the wrapper.

24. The aerosol-generating article according to claim 17, wherein the at least one heat-expandable element further comprises a first layer comprising a first heat-reactive material and a radially outer second layer adjoining the first layer comprising a second heat-reactive material, and wherein a thermal expansion coefficient of the first heat-reactive material is less than a thermal expansion coefficient of the second heat-reactive material.

25. The aerosol-generating article according to claim 16, wherein a distance between the at least one heat-expandable element and a mouth end of the aerosol-generating article is greater than about 50 percent of an overall length of the aerosol-generating article.

26. The aerosol-generating article according to claim 16, wherein a thickness of the at least one heat-expandable element in a non-deformed state is at least about 0.05 millimeters.

27. The aerosol-generating article according to claim 16, further comprising, in linear sequential arrangement, a support element disposed immediately downstream of the aerosol-generating substrate, an aerosol-cooling element disposed downstream of the support element, the wrapper circumscribing the rod, the support element, and the aerosol-cooling element.

28. An aerosol-generating system, comprising: an aerosol aerosol-generating article; and an electrically operated aerosol-generating device comprising a heater and an elongate heating chamber configured to receive the aerosol-generating article so that the aerosol-generating article is configured to be heated in the elongate heating chamber, wherein the aerosol-generating article comprises: a rod of aerosol-generating substrate, a wrapper circumscribing at least the rod, wherein an outer diameter of the circumscribed rod is less than an inner diameter of the elongate heating chamber, and at least one heat-expandable element disposed on an outer surface of the wrapper, the at least one heat-expandable element being configured to deform when heated in the elongate heating chamber such that at least part of the heat-expandable element engages an inner surface of the elongate heating chamber.

29. The aerosol-generating system according to claim 28, wherein the heater comprises a substantially cylindrical, elongate heating element and the elongate heating chamber is disposed about a circumferential, longitudinal surface of the heater.

30. The aerosol-generating system according to claim 28, further comprising an insulation means arranged between the elongate heating chamber and an exterior of the aerosol-generating device configured to reduce heat loss from heated aerosol-generating substrate.

Description

[0082] The invention will now be further described with reference to the figures in which:

[0083] FIG. 1 shows a schematic sectional side view of an aerosol-generating article in accordance with the present invention;

[0084] FIG. 2 shows a schematic sectional side view of an aerosol-generating article in accordance with the present invention received within the heating chamber of an aerosol-generating device prior to the administration of thermal energy; and

[0085] FIG. 3 shows a schematic sectional side view of the aerosol-generating article of FIG. 2 following administration of thermal energy.

[0086] The aerosol-generating article 10 shown in FIG. 1 comprises a rod 12 of aerosol-generating substrate and a wrapper 14 circumscribing the rod 12. An arrow A indicates the direction of flow of the aerosol during use, such that a mouth end 16 of the rod 12 is identified.

[0087] In the embodiment of FIG. 1, a portion of the rod 12 is further circumscribed by a band of pressure-resistant paper 18, which is joined to other portions of the wrapper 14 by another band 20 of wrapper paper.

[0088] Further, the aerosol-generating article 10 comprises a heat-expandable element 22 disposed on the outer surface of the band 20 of wrapper paper. The heat-expandable element 22 is made of an intumescent reactive material which is adapted to expand about 10 times its original dimensions when exposed to heat. The heat-expandable element 22 is provided as an annular element extending about the circumference of the band 20 of wrapper paper, such that the intumescent material is disposed homogeneously about the circumference of the wrapper.

[0089] FIGS. 2 and 3 illustrate another embodiment of an aerosol-generating article 30 in accordance with the invention. The aerosol-generating article 30 comprises a rod 32 of aerosol-generating substrate and a wrapper 34 circumscribing the rod 32. Further, the aerosol-generating article 30 comprises a plurality of heat-expandable elements 36 disposed on the outer surface of the wrapper 34. The heat-expandable elements 36 are arranged substantially equally spaced about the circumference of the wrapper 34. The heat-expandable elements 36 are affixed onto the wrapper 34 by means of a layer of heat-resistant glue 38. Each heat-expandable element 36 comprises a first layer comprising a first heat reactive material and a radially outer second layer adjoining the first layer and comprising a second heat reactive material. A thermal expansion coefficient of the first heat reactive material is less than a thermal expansion coefficient of the second heat reactive material. The aerosol-generating article 30 is received in the heating chamber 50 of an aerosol-generating device 48.

[0090] FIG. 2 shows the aerosol-generating article 30 prior to use, that is, prior to exposure to the heat of the aerosol-generating device 50. Thus, the heat-expandable elements 36 are shown in a non-deformed (that is, non-expanded) state. FIG. 3 shows the aerosol-generating article 30 during use, after exposure to heat sufficient to change the state of the heat-expandable element from non-deformed to expanded. Because of the different thermal expansion coefficients of the two layers 38 and 40, the heat-expandable elements 36 assume a curved C-shaped configuration, such that they may contact the surface of the heating chamber at their respective ends, which effectively bend outwards from a central portion of the heat-expandable element.