Aerosol-generating article comprising a liquid delivery element

Abstract

There is provided an aerosol-generating article (10) comprising an aerosol-generating substrate (12) and a mouthpiece (14) secured to a downstream end of the aerosol-generating substrate (12). The mouthpiece (14) comprises at least one segment of filter material (18) and a liquid delivery element (22). The liquid delivery element (22) comprises an upstream end and a downstream end, a cavity (28) containing a liquid, and at least one channel (26) extending between the upstream end and the downstream end of the liquid delivery element (22). The liquid delivery element (22) is arranged to deliver the liquid to the at least one segment of filter material (18) when activated by a consumer.

Claims

1. An aerosol-generating article having a length extending in a longitudinal direction between upstream and downstream ends of the aerosol-generating article, the aerosol-generating article having a substantially circular cross-sectional shape defining a circumferential direction extending around the longitudinal direction and a radial direction orthogonal to the longitudinal direction and the circumferential direction, the aerosol-generating article comprising an aerosol-generating substrate and a mouthpiece secured to a downstream end of the aerosol-generating substrate, the mouthpiece comprising at least one segment of filter material and a liquid delivery element, the liquid delivery element comprising: an upstream end and a downstream end; a wall defining at least a portion of the boundary of a cavity containing a liquid; said wall comprising a plurality of channel defining surfaces disposed within the wall to define a plurality of channels extending through the wall between the upstream end and the downstream end of the liquid delivery element, wherein each of the plurality of channels has a maximum depth extending in the radial direction and a maximum width extending in the circumferential direction, and wherein the ratio of the maximum depth to the maximum width is between 0.5 to 1 and 2 to 1, and wherein the liquid delivery element further comprises a further wall defining at least a further portion of the boundary of the cavity containing the liquid, said further wall comprising a liquid delivery portion configured to deliver the liquid to the at least one segment of filter material when the liquid delivery element is activated; wherein the wall comprising the plurality of channel defining surfaces of the liquid delivery element is distinct from the wall comprising the liquid delivery portion of the liquid delivery element.

2. An aerosol-generating article according to claim 1, wherein the liquid delivery portion comprises a valve transformable between a closed position and an open position in which the liquid is delivered to the at least one segment of filter material when the liquid delivery element is activated.

3. An aerosol-generating article according to claim 2, wherein the valve comprises a deformable portion and a slit within the deformable portion, wherein the slit is transformable from the closed position to the open position when a force is applied to the liquid delivery element to deform the deformable portion.

4. An aerosol-generating article according to claim 3, wherein the slit is transformable from the open position to the closed position when the force is removed from the liquid delivery element.

5. An aerosol-generating article according to claim 1, wherein the liquid delivery portion comprises a frangible portion, wherein the frangible portion is configured to release the liquid from the cavity when the frangible portion is broken.

6. An aerosol-generating article according to claim 1, wherein the liquid delivery portion comprises an aperture for providing fluid communication between the cavity and exterior of the liquid delivery element, and a sealing portion covering the aperture.

7. An aerosol-generating article according to claim 1, wherein each of the plurality of channels has a minimum cross-sectional area, and wherein the total of the minimum cross-sectional areas for the total number of channels is between 1 square millimetre and 6 square millimetres.

8. An aerosol-generating article according to claim 1, wherein the aerosol-generating article has a resistance to draw of between 5 millimetres of water gauge and 80 millimetres of water gauge before the liquid is delivered from the liquid delivery element into the at least one segment of filter material.

9. An aerosol-generating article according to claim 1, wherein the aerosol-generating article has a resistance to draw of between 15 millimetres of water gauge and 110 millimetres of water gauge after the liquid is delivered from the liquid delivery element into the at least one segment of filter material.

10. An aerosol-generating article according to claim 1, wherein the liquid delivery element is formed from a substantially transparent material.

11. An aerosol-generating article according to claim 1, wherein the liquid delivery element and the at least one segment of filter material each have a substantially circular cross-sectional shape, and wherein the maximum diameter of the liquid delivery element is substantially the same as the maximum diameter of the at least one segment of filter material.

12. An aerosol-generating article according to claim 1, wherein the at least one segment of filter material comprises a downstream filter segment positioned downstream of the liquid delivery element.

13. An aerosol-generating article according to claim 1, wherein the at least one segment of filter material comprises an upstream filter segment and a downstream filter segment downstream of the upstream filter segment, and wherein the liquid delivery element is positioned between the upstream and downstream filter segments.

Description

(1) The invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

(2) FIG. 1 shows a perspective view of an aerosol-generating article in accordance with the present invention;

(3) FIG. 2 shows a longitudinal cross-sectional view of the aerosol-generating article of FIG. 1 and comprising a liquid delivery element in accordance with a first embodiment of the present invention;

(4) FIG. 3 shows the upstream end of the liquid delivery element of the aerosol-generating article of FIG. 2;

(5) FIG. 4 shows a longitudinal cross-sectional view of the aerosol-generating article of FIG. 1 and comprising a liquid delivery element in accordance with a second embodiment of the present invention; and

(6) FIG. 5 shows the upstream end of the liquid delivery element of the aerosol-generating article of FIG. 4.

(7) FIG. 1 shows an aerosol-generating article 10 according to an embodiment of the present invention. The aerosol-generating article 10 is a filter cigarette comprising an aerosol-generating substrate 12 in the form of a wrapped tobacco rod, and a mouthpiece 14. The mouthpiece 14 is secured to the wrapped tobacco rod by a tipping wrapper 16.

(8) As shown more clearly in FIG. 2, which shows a longitudinal cross-sectional view of the aerosol-generating article 10 of FIG. 1, the mouthpiece 14 comprises an upstream filter segment 18 at an upstream end of the mouthpiece 14 and a downstream filter segment 20 at a downstream end of the mouthpiece 14. The mouthpiece 14 further comprises a substantially transparent liquid delivery element 22 positioned between the upstream and downstream filter segments 18, 20. A substantially transparent combining plug wrap 24 is wrapped around the upstream and downstream filter segments 18, 20 and the substantially transparent liquid delivery element 22 to combine them and form the mouthpiece 14.

(9) As shown in FIGS. 2 and 3, the liquid delivery element 22 comprises a plurality of channel defining surfaces 25, each surface defining a respective channel 26. Each channel 26 extends through the liquid delivery element 22 between its upstream and downstream ends. During smoking of the aerosol-generating article 10 mainstream smoke passes from the upstream filter segment 18 to the downstream filter segment 20 through the plurality of channels 26. Each channel 26 has a maximum depth 33 extending in a radial direction and a maximum width 35 extending in a circumferential direction. In the embodiment shown in FIG. 3 each channel 26 has a substantially circular cross-sectional shape so that the ratio of the maximum depth to the maximum width for each channel 26 is approximately 1 to 1.

(10) The liquid delivery element 22 further comprises a cavity 28 positioned within the liquid delivery element, the cavity 28 containing a coloured liquid comprising water. The cavity 28 is open only at its upstream end, the upstream end of the cavity 28 being sealed by a frangible portion in the form of a thin membrane 30. Scoring lines 32 in the thin membrane 30 intersect at the centre of the thin membrane 30 to define an area of weakening in the thin membrane 30.

(11) Before or during smoking of the aerosol-generating article 10 a consumer may squeeze the liquid delivery element 22 to increase the pressure within the cavity 28. The increased pressure will rupture the thin membrane 30 along the scoring lines 32, therefore activating the liquid delivery element and delivering the coloured liquid from the cavity 28 into the upstream filter segment 18. An aperture 34 in the tipping wrapper 16 overlies the substantially transparent liquid delivery element 22 and the substantially transparent combining plug wrap 24 so that, before activation of the liquid delivery element 22, the consumer can observe the coloured liquid within the cavity 28. During activation of the liquid delivery element 22 the consumer can observe, through the aperture 34 in the tipping wrapper 16, the liquid moving out of the cavity 28 and into the upstream filter segment 18. During smoking of the aerosol-generating article 10 the consumer can observe, through the aperture 34 in the tipping wrapper 16, mainstream smoke from the wrapped tobacco rod passing through the plurality of channels 26 in the substantially transparent liquid delivery element 22.

(12) FIGS. 4 and 5 illustrate an aerosol-generating article 100 comprising an alternative liquid delivery element 122. Aside from the liquid delivery element 122, the aerosol-generating article 100 is substantially the same as the aerosol-generating article 10 described with reference to FIGS. 1 to 3, therefore like reference numerals are used to designate like parts.

(13) The liquid delivery element 122 comprises a plurality of channel defining surfaces 125, each surface defining a respective channel 126. Each channel 126 extends between the upstream and downstream ends of the liquid delivery element 122. Each channel 126 is formed by a groove 127 extending along a surface of the liquid delivery element 122 between its upstream and downstream ends, and the combining plug wrap 24 overlying each groove 127. For clarity the plug wrap 24 is spaced apart from the liquid delivery element 122 in FIG. 5, but in practice the plug wrap 24 is glued to the cylindrical surface of the liquid delivery element 122 so that the only space between the plug wrap 24 and the liquid delivery element is in the grooves 127.

(14) The liquid delivery element 122 further comprises an upstream end wall 129 and a slit 131 within the upstream end wall 129. The upstream end wall 129 is deformable when a compressive force is applied to the liquid delivery element 122 so that the upstream end wall 129 forms a deformable portion of the liquid delivery element 122 and the slit 131 forms a valve that is transformable between a closed position and an open position in which the liquid within the cavity 28 can be delivered from the cavity 28 to the upstream filter segment 18.

(15) The embodiments shown in FIGS. 1 to 5 and described above illustrate but do not limit the invention. Other embodiments of the invention may be made without departing from the scope thereof, and it is to be understood that the specific embodiments described herein are not limiting. For example, forming the at least one channel using a groove, as shown in FIGS. 4 and 5, can be combined with a cavity sealed with a frangible portion, as shown in FIGS. 2 and 3. Similarly, forming the liquid delivery element so that the at least one channel extends through the liquid delivery element, as shown in FIGS. 2 and 3, can be combined with a cavity comprising a valve, as shown in FIGS. 4 and 5. Furthermore, it will be appreciated that whilst the specific embodiments described above relate to a conventional smoking article comprising a combustible tobacco rod, similar arrangements could also be used on a distillation-based smoking article or an electrically heated smoking article.