AEROSOL-GENERATING ARTICLE HAVING A THERMAL INDICATOR

Abstract

An aerosol-generating article for an aerosol-generating device having a heating element is provided, the article including: a rod of aerosol-generating substrate formed of an aerosol-forming material having an aerosol former content of between 5 percent and 30 percent on a dry weight basis; and an outer wrapper wrapped around at least a portion of the rod, and at least a portion of an outer surface of the wrapper includes a thermal indicator including a thermochromic material, at least a portion of which is configured to undergo a visual change when a temperature at the portion exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, the threshold temperature being at least about 175 C.

Claims

1.-15. (canceled)

16. An aerosol-generating article for an aerosol-generating device having a heating element, the aerosol-generating article comprising: a rod of aerosol-generating substrate, the rod of aerosol-generating substrate being formed of an aerosol-forming material having an aerosol former content of between 5 percent and 30 percent on a dry weight basis; and an outer wrapper, wherein the outer wrapper is wrapped around at least a portion of the rod of aerosol-generating substrate and at least a portion of an outer surface of the wrapper comprises a thermal indicator, the thermal indicator comprising: a thermochromic material, whereby at least a portion of the thermochromic material is configured to undergo a visual change when a temperature at said portion of the thermochromic material exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, wherein the threshold temperature is at least about 175 degrees Celsius.

17. An aerosol-generating article for an aerosol-generating device having a heating element, the aerosol-generating article comprising: a rod of aerosol-generating substrate; and an outer wrapper, wherein the outer wrapper is wrapped around at least a portion of the rod of aerosol-generating substrate and at least a portion of an outer surface of the wrapper comprises a thermal indicator, the thermal indicator comprising: a thermochromic material, whereby at least a portion of the thermochromic material is configured to undergo a visual change when a temperature at said portion of the thermochromic material exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, wherein the threshold temperature is at least about 175 degrees Celsius, wherein the thermal indicator overlies at least 5 square millimetres of an external surface area of the rod of aerosol-generating substrate.

18. An aerosol-generating article for an aerosol-generating device having a heating element, the aerosol-generating article comprising: a rod of aerosol-generating substrate; and an outer wrapper, wherein the outer wrapper is wrapped around at least a portion of the rod of aerosol-generating substrate and at least a portion of an outer surface of the wrapper comprises a thermal indicator, the thermal indicator comprising: a thermochromic material, whereby at least a portion of the thermochromic material is configured to undergo a visual change when a temperature at said portion of the thermochromic material exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, wherein the threshold temperature is at least about 220 degrees Celsius.

19. The aerosol-generating article according to claim 16, wherein the threshold temperature is at least about 220 degrees Celsius.

20. The aerosol-generating article according to claim 16, wherein the thermal indicator overlies at least 5 square millimetres of an external surface area of the rod of aerosol-generating substrate.

21. The aerosol-generating article according to claim 16, wherein the thermal indicator extends longitudinally along at least 50 percent of a total length of the rod of aerosol-generating substrate.

22. The aerosol-generating article according to claim 16, wherein the thermochromic material is arranged such that the visual change occurs only within a circumferential portion of the outer wrapper, and wherein the circumferential portion extends only partially around a circumference of the aerosol-generating article.

23. An aerosol-generating article for an aerosol-generating device having a heating element, the aerosol-generating article comprising: a rod of aerosol-generating substrate, the rod of aerosol-generating substrate being formed of an aerosol-forming material having an aerosol former content of between 5 percent and 30 percent on a dry weight basis; and an outer wrapper, wherein at least a portion of an outer surface of the wrapper comprises a thermal indicator, wherein the thermal indicator is disposed downstream of the rod of aerosol-generating substrate, the thermal indicator comprising: a thermochromic material, whereby at least a portion of the thermochromic material is configured to undergo a visual change when a temperature at said portion of the thermochromic material exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, wherein the threshold temperature is at least about 115 degrees Celsius.

24. The aerosol-generating article according to claim 16, wherein the visual change is irreversible.

25. The aerosol-generating article according to claim 16, wherein the thermal indicator extends longitudinally along at least 20 percent of a total length of the aerosol-generating article.

26. The aerosol-generating article according to claim 16, wherein the visual change comprises a colour change.

27. The aerosol-generating article according to claim 16, wherein the visual change comprises displaying a graphical representation and/or warning indicia or messages.

28. The aerosol-generating article according to claim 16, wherein the outer wrapper comprises temperature indicating sensor paper, whereby the thermochromic material is integral to the temperature indicating sensor paper.

29. The aerosol-generating article according to claim 16, wherein the thermochromic material comprises thermochromic paint, ink, or dye applied to the at least a portion of the outer surface of the wrapper.

30. The aerosol-generating article according to claim 16, further comprising: a mouthpiece disposed downstream of the rod of aerosol-generating substrate; a support element disposed immediately downstream of the rod of aerosol-generating substrate; and an aerosol-cooling element disposed between the support element and the mouthpiece.

31. A thermochromic material in a thermal indicator disposed on an outer wrapper of a rod of aerosol-generating substrate of an aerosol-generating article, the rod of aerosol-generating substrate being formed of an aerosol-forming material having an aerosol former content of between 5 percent and 30 percent on a dry weight basis and the aerosol-generating article being configured to be used with an aerosol-generating device having a heating element, wherein the outer wrapper is wrapped around at least a portion of the rod of aerosol-generating substrate and whereby at least a portion of the thermochromic material is configured to undergo a visual change when a temperature at said portion of the thermochromic material exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, wherein the threshold temperature is at least about 175 degrees Celsius.

32. A thermochromic material in a thermal indicator disposed on an outer wrapper of an aerosol-generating article, the aerosol-generating article being configured to be used with an aerosol-generating device having a heating element, and the aerosol-generating article comprising a rod of aerosol-generating substrate, the rod of aerosol-generating substrate being formed of an aerosol-forming material having an aerosol former content of between 5 percent and 30 percent on a dry weight basis, whereby the thermal indicator is disposed downstream of the rod of aerosol-generating substrate and at least a portion of the thermochromic material is configured to undergo a visual change when a temperature at said portion of the thermochromic material exceeds a threshold temperature, such that the outer wrapper provides a visual indication that a temperature at the thermal indicator has exceeded the threshold temperature, wherein the threshold temperature is at least about 115 degrees Celsius.

33. An aerosol-generating system, comprising: an aerosol-generating article according to claim 16; and an aerosol-generating device configured to receive the aerosol-generating article, the aerosol-generating device comprising a heater element configured to heat a rod of aerosol-generating material, wherein the heater element is configured so as to be controlled to operate below a maximum operating temperature, wherein a thermal indicator of the aerosol-generating article is configured such that a threshold temperature is not exceeded during use of the aerosol-generating system with the heater element operating below the maximum operating temperature.

Description

[0099] The invention will now be further described with reference to the figures in which:

[0100] FIG. 1 shows a perspective view of an aerosol-generating article according to the present invention;

[0101] FIG. 2 shows a perspective view of an aerosol-generating article having an activated thermal indicator according to a first embodiment of the invention;

[0102] FIG. 3 shows a perspective view of an aerosol-generating article having an activated thermal indicator according to a second embodiment of the invention;

[0103] FIG. 4 shows a perspective view of an aerosol-generating article having an activated thermal indicator according to a third embodiment of the invention;

[0104] FIGS. 5a and 5b show a schematic cross-sectional view of an aerosol-generating system comprising an aerosol-generating device and an aerosol generating article according to the invention;

[0105] The aerosol-generating article 10 shown in the figures comprises four elements arranged in coaxial alignment: a rod of aerosol-generating substrate 20, a support element 30, an aerosol-cooling element 40, and a mouthpiece 50 (shown in FIGS. 5a and 5b). Each of the four elements is circumscribed by a corresponding plug wrap (not shown). These four elements are arranged sequentially and are circumscribed by an outer wrapper 60 to form the aerosol-generating article 10. The aerosol-generating 10 has a proximal or mouth end 70, which a user inserts into his or her mouth during use, and a distal end 80 located at the opposite end of the aerosol-generating article 10 to the mouth end 70.

[0106] In use air is drawn through the aerosol-generating article by a user from the distal end 80 to the mouth end 70. The distal end 80 of the aerosol-generating article may also be described as the upstream end of the aerosol-generating article 10 and the mouth end 70 of the aerosol-generating article 10 may also be described as the downstream end of the aerosol-generating article 10. Elements of the aerosol-generating article 10 located between the mouth end 70 and the distal end 80 can be described as being upstream of the mouth end 70 or, alternatively, downstream of the distal end 80.

[0107] The support element 30 is in place to prevent the aerosol-generating substrate 20 from being forced downstream within the aerosol-generating article 10 towards the aerosol-cooling element 40 when a heating element of an aerosol-generating device is inserted into the aerosol-generating substrate 20. The support element 30 also acts as a spacer to space the aerosol-cooling element 40 of the aerosol-generating article 10 from the aerosol-generating substrate 20.

[0108] The aerosol-cooling element 40 is located immediately downstream of the support element 30. In use, volatile substances released from the aerosol-generating substrate 20 pass along the aerosol-cooling element 40 towards the mouth end 70 of the aerosol-generating article 10. The volatile substances may cool within the aerosol-cooling element 40 to form an aerosol that is inhaled by the user. The aerosol-cooling element comprises a crimped and gathered sheet of polylactic acid circumscribed by a wrapper 60. The crimped and gathered sheet of polylactic acid defines a plurality of longitudinal channels that extend along the length of the aerosol-cooling element 40.

[0109] The mouthpiece 50 is located immediately downstream of the aerosol-cooling element 40 and abuts the aerosol-cooling element 40. The mouthpiece 50 comprises a conventional cellulose acetate tow filter of low filtration efficiency.

[0110] To assemble the aerosol-generating article 10, the four elements described above are aligned and tightly wrapped within the outer wrapper 60. In the embodiments illustrated in the figures, the outer wrapper 60 comprises conventional cigarette paper. A distal end portion of the outer wrapper 60 of the aerosol-generating article 10 is circumscribed by a band of tipping paper (not shown).

[0111] The aerosol-generating substrate 20 is located at the extreme distal or upstream end of the aerosol-generating article 10. As illustrated in FIGS. 5a and 5b, the aerosol-generating substrate 20 comprises a gathered sheet of crimped homogenised tobacco material circumscribed by a wrapper. The crimped sheet of homogenised tobacco material comprises glycerin as an aerosol former.

[0112] A thermal indicator 100 is provided at a location on the outer surface of the outer wrapper 60. The thermal indicator 100 comprises thermochromic material which is configured to undergo a visual change when the temperature at the thermal indicator 100 is above a threshold temperature.

[0113] FIG. 1 shows the outer wrapper 60 of the aerosol-generating article prior to activation of the thermal indicator 100. In the following embodiments described herein, the thermal indicator 100 is not visible until it activates or starts to undergo visual change when the temperature is above the threshold temperature.

[0114] FIG. 2 shows the article 10 after the activation of a thermal indicator 101, according to a first embodiment, when the temperature at the thermal indicator 101 is above a threshold temperature of the thermochromic material. In this first embodiment, the thermal indicator is located around the rod of aerosol-generating substrate 20 and the threshold temperature is, at least, about 175 C. In the first embodiment of the article 10, the thermal indicator 101 extends longitudinally along the entire length of the rod of aerosol-generating substrate 20. However, in other arrangements in accordance to the first embodiment, the thermal indicator 101 may extend partially longitudinally along the rod of aerosol-generating substrate. For example, the thermal indicator 101 may extend at least 50% of the total length of the rod of aerosol-generating substrate 20.

[0115] FIG. 3 shows the article 10 after the activation of a thermal indicator 102, according to a second embodiment, when the temperature at the thermal indicator 102 is above a threshold temperature. In this second embodiment, the thermal indicator is located partially around the rod of aerosol-generating substrate 20 or the thermal indicator 102 does not totally circumscribe the outer surface of the aerosol-generating article. The threshold temperature of the thermal indicator 102 is, at least, about 175 C. However, the threshold temperature for thermal indicator 102 according to the second embodiment may likely be higher than the threshold temperature of the thermal indicator 101 according to the first embodiment.

[0116] FIG. 4 shows the article 10 after the activation of the thermal indicator 103, according to a third embodiment, when the temperature at the thermal indicator 103 is above a threshold temperature. In this third embodiment, the thermal indicator 103 is located around the article 10 at a position downstream of the rod of aerosol-generating substrate, away from the distal end 80 of the article 10. The thermal indicator 103 may partially circumscribe the outer surface of the aerosol-generating article and may also circumscribe a portion of the rod of aerosol-generating substrate. The threshold temperature of the thermal indicator 103 is, at least, about 115 C. The threshold temperature of the third embodiment may be lower than that of the first and second embodiments due to the relative distance of the thermal indicator 103 from the aerosol-generating substrate 20.

[0117] As described in detail above, the visual change of the thermal indicator is configured to inform a user of the article 10 that the aerosol-generating substrate 20 of the article 10 has been overheated either because the article 10 has been misused with an incompatible aerosol-generating device or because the article has been used with an aerosol-generating device which may be malfunctioning in a manner that it is overheating the aerosol-generating substrate 20. Consequently, in order to convey such information of misuse of the article 10, the visual change of the thermal indicators 101, 102, 103 are preferably irreversible such that the visual change, upon removal of the article 10 from an aerosol-generating device, does not disappear and remains visible to the user when the substrate 20 has cooled. As shown in FIGS. 2, 3 and 4; the irreversible visual change comprises a colour change from colourless to red and the appearance of warning messages or graphical representations.

[0118] The aerosol-generating articles illustrated in the above described figures are designed to engage with an aerosol-generating device comprising a heating element in order to be consumed by a user. In use, the heating element of the aerosol-generating device heats the aerosol-generating substrate of the aerosol-generating article to a sufficient temperature to form an aerosol, which is drawn downstream through the aerosol-generating article and inhaled by the user.

[0119] FIGS. 5a and 5b illustrate an aerosol-generating system 500 comprising an aerosol-generating device 510 and an aerosol-generating article 10 according to any of the embodiments described above and shown in the figures described above. It will be appreciated that the aerosol-generating device 510 could be used in combination with an alternative aerosol-generating article according to the invention.

[0120] The aerosol-generating device 510 comprises a heating element 520. As shown in FIGS. 5a and 5b, the heating element 520 is mounted within an aerosol-generating article receiving chamber 515 of the aerosol-generating device 510. In use, the user inserts the aerosol-generating article 10 into the aerosol-generating article receiving chamber 515 of the aerosol-generating device 510 such that the heating element 520 is directly inserted into the aerosol-generating substrate 20 of the aerosol-generating article 10 as shown in FIG. 5b. In the embodiment shown in FIGS. 5a and 5b, the heating element 520 of the aerosol-generating device 510 is a heater blade.

[0121] The aerosol-generating device 510 comprises a power supply and electronics (not shown) that allow the heating element 520 to be actuated. Such actuation may be manually operated or may occur automatically in response to a user drawing on an aerosol-generating article 10 inserted into the aerosol-generating article receiving chamber of the aerosol-generating device 510. A plurality of openings (not shown) may be provided in the aerosol-generating device 510 to allow air to flow to the aerosol-generating article 10.

[0122] Once the internal heating element 520 is inserted into the aerosol-generating substrate 20 of the aerosol-generating article 10 and the heating element 520 is actuated, the aerosol-generating substrate 20 of the aerosol-generating article 10 is heated to a temperature of approximately 350 C. by the heating element 520 of the aerosol-generating device 510. At this temperature, volatile compounds are evolved from the aerosol-generating substrate 20 of the aerosol-generating article 10. As a user draws on the mouth end 70 of the aerosol-generating article 10, the volatile compounds evolved from the aerosol-generating substrate 20 are drawn downstream through the aerosol-generating article 10 and condense to form an aerosol that is drawn through the mouthpiece 50 of the aerosol-generating article 10 into the user's mouth.

[0123] As the aerosol passes downstream thorough the aerosol-cooling element 40, the temperature of the aerosol is reduced due to transfer of thermal energy from the aerosol to the aerosol-cooling element 40. When the aerosol enters the aerosol-cooling element 40, its temperature is approximately 60 C. Due to cooling within the aerosol-cooling element 40, the temperature of the aerosol as it exits the aerosol-cooling element is approximately 40 C.

[0124] In FIGS. 5a and 5b, the heating element 520 of the aerosol-generating device 510 is shown in a simplified manner. Particularly, the heating element 520 of the aerosol-generating device 510 is not drawn to scale in FIGS. 5a and 5b. Components that are not relevant for the understanding of the embodiment have been omitted to simplify FIGS. 5a and 5b.

[0125] As shown in FIGS. 5a and 5b, the aerosol-generating device 510 comprises a housing 530. The heating element 520 is mounted within an aerosol-generating article receiving chamber within the housing 530. The aerosol-generating article 10 is inserted into the aerosol-generating article receiving chamber 515 within the housing 530 of the aerosol-generating device 510 such that the heating element 520 is directly inserted into the aerosol-generating substrate 20 of the aerosol-generating article 10.

[0126] Within the housing 530 there is an electrical energy supply (not shown), for example a rechargeable lithium ion battery. A controller (not shown) is connected to the heating element 520, the electrical energy supply, and a user interface (not shown), for example a button or display. The controller of the aerosol-generating device controls the power supplied to the heating element 520 in order to regulate its temperature.

[0127] During this normal usage of the aerosol-generating articles according to the invention with the compatible aerosol-generating device 510 shown in FIGS. 5a and 5b, the thermal indicator of the aerosol-generating article remains inactivated due to the use of the article with a compatible aerosol-generating device and, as such, overheating does not occur in the aerosol-generating substrate.

[0128] In the event that the aerosol-generating articles according to the invention are used with an incompatible device and are overheated to above a preferred maximum operating temperature, the thermal indicator will activate, that is undergo a visual change, upon reaching the predetermined threshold temperature of the thermal indicator. Upon removal of the article from the aerosol-generating device, the user will be informed of the misuse of the article when she sees the activated thermal indicator of the articles.

[0129] As such, the incorporation of the thermal indicator into the aerosol-generating articles of the present invention provides an effective means of protecting the consumer from use of the aerosol-generating article in an unintended manner in an incompatible device and/or from use of the article in a defective or malfunctioning compatible device.