Aerosol-generating article and low resistance support element for use as segment in an aerosol-generating article

Abstract

The aerosol-generating article (10) comprises a plurality of segments assembled in the form of a rod (11). The plurality of segments includes an aerosol-forming substrate (20) and a mouthpiece filter (50) located downstream from the aerosol-forming substrate (20) within the rod (11). The aerosol-generating article (10) further comprises activated carbon (45) disposed between the aerosol-forming substrate (20) and the mouthpiece filter (50) within the rod (11).

Claims

1. An aerosol-generating article comprising a plurality of segments assembled in the form of a rod, the plurality of segments including an aerosol-forming substrate and a mouthpiece filter located downstream from the aerosol-forming substrate within the rod, the aerosol-generating article further comprising between 0.008 milligram and 0.05 milligram of activated carbon disposed between the aerosol-forming substrate and the mouthpiece filter within the rod, wherein the activated carbon is coupled to an elongated carbon support element in the form of a thread.

2. The aerosol-generating article according to claim 1, wherein the activated carbon is provided in particle form, the particles having sizes in a range between 0.1 micrometer and 10 micrometer.

3. The aerosol-generating article according to claim 1, wherein the thread is made of fibers or filaments, and wherein particles of activated carbon are incorporated into the fibers or filaments.

4. The aerosol-generating article according to claim 1, wherein a weight of the activated carbon to a weight of the carbon support element on a dry weight basis is in a range between 0.05 percent and 0.5 percent.

5. The aerosol-generating article according to claim 1, wherein the plurality of segments are assembled within a wrapper to form the rod, the elongated carbon support element being disposed radially inward from an inner surface of the wrapper within the rod and having a longitudinal dimension disposed substantially parallel to a longitudinal axis of the rod.

6. The aerosol-generating article according to claim 1, comprising a low resistance support element located upstream of the mouthpiece and downstream of the aerosol-forming substrate, the low resistance support element having a porosity between 50 percent and 90 percent in the longitudinal direction and providing a low resistance to draw (RTD), and comprising a longitudinally extending channel for locating the activated carbon within the longitudinally extending channel.

7. The aerosol-generating article according to claim 6, wherein the low resistance support element is formed of or comprises a material selected from the group comprising polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, polylactic acid, cellulose acetate, starch based copolyester, paper, and aluminium.

8. The aerosol-generating article according to claim 6, wherein the low resistance support element is an aerosol-cooling element having a total surface area of between 300 mm.sup.2 per mm length and 1000 mm.sup.2 per mm length.

9. The aerosol-generating article according to claim 7, wherein the low resistance support element is an aerosol-cooling element having a total surface area of between 300 mm.sup.2 per mm length and 1000 mm.sup.2 per mm length.

10. A low resistance support element for use as segment of an aerosol-generating article, the low resistance support element having a porosity between 50 percent and 90 percent in the longitudinal direction and comprising at least one longitudinally extending channel, wherein between 0.008 milligram and 0.05 milligram of activated carbon is coupled to an elongated carbon support element in the form of a thread, which elongated carbon support element is located within the at least one longitudinally extending channel.

11. A low resistance support element according to claim 10, wherein the elongated carbon support element is formed by filaments, wherein the activated carbon is in the form of particles, and wherein the particles of activated carbon are incorporated in the filaments forming the elongated carbon support element.

Description

(1) The invention is further described with regard to an embodiment, which is illustrated by means of the FIGURE.

(2) The FIGURE is a schematic cross-sectional diagram of an aerosol-generating article 10. The article 10 comprises four elements, an aerosol-forming substrate 20, a hollow cellulose acetate tube 30, a low resistance support element 40 comprising an activated carbon containing thread 45, and a mouthpiece filter 50. These four elements are arranged sequentially and in coaxial alignment and are assembled by a wrapping material 60, for example a cigarette paper, to form a rod 11. The rod 11 has a mouth end 12, which a user may insert into his or her mouth during use, and a distal end 13 located at the opposite end of the rod 11 and to the mouth end 12. Elements located between the mouth end 12 and the distal end 13 can be described as being upstream of the mouth end 12 or, alternatively, downstream of the distal end 13. The article illustrated in the FIGURE is suitable for use with an aerosol-generating device comprising a heater for heating the aerosol-forming substrate.

(3) When assembled, the rod 11 is about 45 mm in length and has an outer diameter of about 7.2 mm.

(4) The aerosol-forming substrate 20 is located upstream of the hollow tube 30 and extends to the distal end 13 of the rod 11. The aerosol-forming substrate 20 preferably comprises a bundle of crimped cast-leaf tobacco wrapped in a wrapping paper (not shown) to form a plug. The cast-leaf tobacco includes additives, including, for example, glycerine as an aerosol-forming additive. The aerosol-forming substrate may also comprise susceptor material, depending on the way of heating the substrate 20 as will be described in more detail below.

(5) The hollow tube 30 is located immediately downstream of the aerosol-forming substrate 20 and is formed from cellulose acetate. One function of the hollow tube 30 is to locate the aerosol-forming substrate 20 towards the distal end 13 of the rod 11 so that it can be contacted with a heating element. The hollow tube 30 acts to prevent the aerosol-forming substrate 20 from being forced along the rod 11 towards the low resistance support element 40, for example, when a heating element is inserted into the aerosol-forming substrate 20. The hollow tube 30 also acts as a spacer element to space the low resistance support element 40 from the aerosol-forming substrate 20.

(6) The low resistance support element 40 has a length of about 18 mm with a mouthpiece filter 50 as shown in the FIGURE. In an aerosol-generating article comprising a recessed filter, typically the mouthpiece filter is supplemented with a tubular element, for example a cardboard tube, forming the recess at the mouthpiece end 12 of the article 10. In such embodiments, the length of the low resistance element is about 13 mm.

(7) The low resistance support element has an outer diameter of about 7.1 mm. The low resistance support element 40 is formed from a sheet of polylactic acid having a thickness of 50 mm plus or minus 2 mm. The sheet of polylactic acid has been crimped and gathered to define a plurality of channels that extend along the length of the low resistance support element 40. Such a low resistance support element forms an aerosol-cooling element. To form the element, a sheet of polylactic acid is fed through crimping rollers to produce longitudinal crimps or corrugations. The crimped sheet is then gathered to form a cylinder having a plurality of longitudinally extending channels. During the formation of the support element 40, an active carbon containing thread 45 is deposited into the crimped sheet parallel to the longitudinal crimps. Thus, the activated carbon containing thread 45 is incorporated within a longitudinal channel of the low resistance support element 40 as it is formed. The activated carbon containing thread 45 has a same length as the low resistance support element 40 and extends along the longitudinal axis of the low resistance support element 40 and of the article 10. The activated carbon containing thread 45 is loaded with a sufficient amount of activated carbon so as to provide an activated carbon load to element 40 of approximately 0.02 mg carbon.

(8) The carbon containing thread 45 may be a cotton thread or an acetate thread. Preferably, the thread 45 is made of cellulose acetate filaments, wherein activated carbon particles have been incorporated during manufacture of the filaments, for example during extrusion. The filaments may be threaded or woven to form the thread 45. The total surface area of the low resistance support element 40 is between 8000 mm.sup.2 and 9000 mm.sup.2, which is equivalent to approximately 500 mm.sup.2 per mm length. The specific surface area of the low resistance support element 40 is approximately 2.5 mm.sup.2 per mg and it has a porosity of between 60 percent and 90 percent in the longitudinal direction.

(9) Porosity is defined herein as a measure of unfilled space in a rod including an aerosol-cooling element consistent with the one discussed herein. For example, if a diameter of the rod 11 was 50 percent unfilled by the low resistance support element 40, the porosity would be 50 percent. Likewise, a rod would have a porosity of 100 percent if the inner diameter was completely unfilled and a porosity of 0 percent if completely filled. The porosity may be calculated using known methods. An exemplary illustration of how porosity may be calculated is for example described and shown in the international patent publication WO 2013/120566.

(10) The higher the porosity in the longitudinal direction, the lower the resistance of the element 40.

(11) The mouthpiece filter 50 is a conventional mouthpiece filter formed from cellulose acetate, and having a length of about 7 millimetres.

(12) The four elements identified above are assembled by being tightly wrapped within the wrapping material 60. The wrapping material 60 may be a conventional cigarette paper having standard properties. The interference between the wrapping material 60 and each of the elements locates the elements and defines the rod 11 of the aerosol-generating article 10.

(13) Although the specific embodiment illustrated in the FIGURE has four elements assembled in a cigarette paper, it is clear than an aerosol-generating article may have additional elements or fewer elements.

(14) An aerosol-generating article 10 as illustrated in the FIGURE is designed to engage with an aerosol-generating device (not shown) in order to be consumed. Such an aerosol-generating device includes means for heating the aerosol-forming substrate 20 to a sufficient temperature to form an aerosol. Typically, the aerosol-generating device may comprise a heating element that surrounds the aerosol-generating article adjacent to the aerosol-forming substrate 20, a heating element that is inserted into the aerosol-forming substrate 20 or an inductor that may inductively heat an inductively heatable material provided within the aerosol-forming substrate or in thermal contact with the aerosol-forming substrate. Once engaged with an aerosol-generating device, the aerosol-forming substrate 20 is heated to a temperature of above 250 degrees Celsius and a user may draw on the mouth end 12 of the aerosol-generating article 10. At this temperature, volatile compounds are evolved from the aerosol-forming substrate 20. These compounds condense to form an aerosol. The aerosol is drawn through the rod 11 towards the mouth end 12.

(15) As the aerosol is drawn through the rod 11, the activated carbon containing thread 45 and the mouthpiece filter 50 is also entrained in the aerosol to provide a specific freshness experience for a user.

(16) In a variant of the embodiment shown in the FIGURE the article is not designed to engage with an aerosol-generating device but comprises a combustible heat source that may be ignited and transfer heat to the aerosol-forming substrate 20 to form an inhalable aerosol. The combustible heat source may be a charcoal element that is assembled in proximity to the aerosol-forming substrate at the distal end 13 of the rod 11. The other elements of the aerosol-generating article may be the same.