Filter for Smoking Article

Abstract

A filter for a vapour generating article includes a filter body having: a first end arranged as a mouthpiece; a second end opposite the first end arranged for attachment to a vapour generating article; the filter further including a cavity located within the filter body between the first and second ends, the cavity configured to allow a fluid including water to flow through the filter body from the second end to the first end; wherein the cavity includes a filter portion arranged to filter the fluid as it flows through the filter body; and wherein the filter portion is arranged to remove at least some of the water from the fluid as it flows through the filter body.

Claims

1. A filter for a vapour generating article comprising: a filter body comprising: a first end arranged as a mouthpiece; and a second end opposite the first end arranged for attachment to a vapour generating article; and a cavity located within the filter body between the first and second ends, the cavity configured to allow a fluid comprising water to flow through the filter body from the second end to the first end; wherein the cavity comprises a filter portion arranged to filter the fluid as the fluid flows through the filter body; and wherein the filter portion is arranged to remove at least some of the water from the fluid as the fluid flows through the filter body.

2. The filter of claim 1, wherein the filter portion comprises a selective filter medium arranged to selectively filter water from the fluid.

3. The filter of claim 2, wherein the selective filter medium comprises a water-absorbing medium.

4. The filter of claim 3, wherein the water-absorbing medium comprises silica.

5. The filter of claim 3, wherein the water-absorbing medium comprises a molecular sieve.

6. The filter of claim 3, wherein the water-absorbing medium comprises a hydrophilic sponge material.

7. The filter according to claim 1, wherein the second end of the filter is releasably attachable to a vapour generating article.

8. A vapour generating article comprising: a first end arranged for connection with a vapour generating device; a filter according to claim 1, wherein the filter is attached to a second end of the vapour generating article.

9. A vapour generating system comprising: a filter according to claim 1; a vapour generating article comprising a first end arranged for connection with a vapour generating device, wherein the filter is attached to a second end of the vapour generating article; and a vapour generating device configured to receive the vapour generating article.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0020] Embodiments of the present invention will be now described by way of example only with reference to the accompanying drawing in which:

[0021] FIG. 1 shows an example aerosol generating article.

DETAILED DESCRIPTION

[0022] Referring to FIG. 1 an example aerosol generating article 1, in the form of an elongate consumable 1, is shown located within an aerosol generating device 2 in order to generate an aerosol.

[0023] The aerosol generating article 1 comprises a rod-shaped portion 11, and a filter 14.

[0024] The rod-shaped portion 11 comprises aerosol generating substrate 12 that extends over a portion of the length of the rod-shaped portion 11. The aerosol generating substrate 12 is arranged at an end of the aerosol generating article 1 that is within a heating chamber of the aerosol generating device 2 and furthest from an opening of the heating chamber. The aerosol generating substrate 12 is a material which, when heated, generates an aerosol. The aerosol generating substrate 12 may, for example, comprise tobacco or nicotine. The aerosol is drawn out of the aerosol generating article 1 by air flow through the filter 14.

[0025] The aerosol generating device 2 comprises a heating chamber 21 and a heater 22.

[0026] The heating chamber 21 is a tubular structure with an internal hollow in which the aerosol generating article 1, or the rod-shaped portion 11 of the aerosol generating article 1, may be received. Specifically, the heating chamber comprises a side wall extending between a first end 212 and a second end 213. The first end 212 is open, or openable in use, in order to allow the rod-shaped portion 11 to be inserted. The second end 213 may be open as shown in FIG. 1A, in order to provide an air inlet for air to flow through the aerosol generating article. Alternatively, the second end 213 may be closed in order to improve heating efficiency of the heating chamber 21.

[0027] The heating chamber 21 may be formed from ceramic or metal. For example, the heating chamber 21 may be formed by bending or stamping sheet metal. The heater 22 may be any heater suitable to deliver heat into the internal hollow of the heating chamber 21 through its side wall. For example, the heater may be in the form of a resistive track driven by electricity. Alternatively, other types of heater may be used such as ones in which heat is provided by a chemical reaction such as fuel combustion. The heating chamber may further be surrounded by a heat insulator such as a vacuum tube, heat insulation fibre and/or aerogel.

[0028] In use, the heater 22 is arranged to heat the heating chamber 21 to a temperature sufficient to cause the aerosol generating substrate 12 to release an aerosol, without burning the aerosol generating article 1. In particular, the heater 22 is configured to heat the aerosol generating substrate 12 to a maximum temperature between 150 C. and 350 C., more preferably to a temperature between 200 C. and 350 C.

[0029] Although the heater 22 is shown outside the heating chamber 21 in FIG. 1A, the heater 22 may in some embodiments be arranged inside the heating chamber 21.

[0030] The aerosol generating article 1 further comprises an aerosol cooling region 15. The aerosol cooling region 15 extends over a portion of the length of the aerosol generating article 1 and comprises a hollow tubular portion of the aerosol generating article 1. This hollow tubular portion allows an aerosol (generated by heating the aerosol generating substrate 12) to pass through the aerosol generating article 1 without leaking through the sides of the hollow tubular portion. The aerosol cooling region 15 does not overlap with the part of the aerosol generating article 1 that is being heated by the heater 22, which may be referred to as a heating region, so aerosol will not continue to be heated within the aerosol cooling region 15.

[0031] As mentioned, the aerosol substrate 15 is arranged at the end of the aerosol generating article 1 that is within the heating chamber 21 and furthest from the opening 212. The filter 14 is arranged at the other end that is closest to the opening 212. The aerosol cooling region 15 extends along the length of the aerosol generating article 1 between the aerosol generating substrate 12 and the filter 14. This ensures that, in use, a generated aerosol may be cooled before inhalation by a user.

[0032] Further details of the filter 14 will now be described.

[0033] The filter 14 comprises a filter body 114 having a first end 102 in the form of a mouthpiece and a second end 104, opposite the first end 102, for attaching to the rod-shaped portion 11 of the aerosol generating article 1. The filter 14 further comprises a cavity 106 which is located within the filter body 114 between the first and second ends. The cavity 106 allows a fluid, comprising water, to flow through the filter body 114 from the second end 104 to the first end 102. The cavity 106 comprises a filter portion 108 which filters the fluid as it flows through the filter body 114. In particular, the filter portion 108 removes at least some of the water from the fluid as it flows through the filter body 114. It should be noted that the fluid in this context refers to the aerosol or vapour that has been generated by the aerosol generating article 1.

[0034] The filter 14 is typically made of any suitable plastic material, and the aerosol generating article 1 is typically made from paper.

[0035] In order to more efficiently remove water from the vapour as it passes through the filter body 114, the filter portion comprises a selective water absorbing media which selectively absorbs water from the fluid, in preference over other liquids within the fluid. Any suitable selective water absorbing media can be used for example silica, molecular sieves, or hydrophilic sponge materials.

[0036] In use, when the user draws on the mouthpiece end 102 of the filter and vapour is inhaled through the filter 14, the selective water-absorbing media removes water from the vapour to be inhaled, which reduces the humidity of the inhaled vapour. Since water has a relatively high specific heat capacity, a vapour with a high humidity can be very hot which can be dangerous and unpleasant for the user to inhale. Thus, reducing the humidity within the filter helps lower the temperature of the inhaled vapour which provides a safer aerosol generating article 1, as well as improves the overall sensory experience for the user.

[0037] The filter 14 is re-usable filter 14 because it can be detached from one rod-shaped portion 11 of a first aerosol generating article 1, at the second end 104, and the re-attached to another rod-shaped portion 11 of a second aerosol generating article 1 via the second end 104. In particular, the filter 14 may slot into or onto the rod-shaped portion 11 using any suitable temporary attachment mechanism. The filter 14 can therefore be considered as being releasably attachable and able to be used with multiple aerosol generating articles. In other words, the filter 14 can be said to be semi-disposable.

[0038] Thus, when the filter 14 is attached to the rod-shaped portion 11, a vapour generating article 1 is formed. In particular, the vapour generating article 1 includes a first end and a second end, and the filter 14 attaches to the second end of the vapour generating article 1. The first end of the vapour generating article 1 may be used to connect with a vapour generating device 2. In this case, a vapour generating system is formed comprising the a vapour generating article 1 and the vapour generating device 2 which receives the vapour generating article 1.

[0039] It should be understood that the aerosol generation device is an electronic cigarette which could equally be referred to as a heated tobacco device, a heat-not-burn tobacco device, a device for vaporising tobacco products, and the like, with this being interpreted as a device suitable for achieving these effects. The features disclosed herein are equally applicable to devices which are designed to vaporise any aerosol generating medium.

[0040] The aerosol generating substrate 12 may include tobacco, for example in dried or cured form, in some cases with additional ingredients for flavouring or producing a smoother or otherwise more pleasurable experience. In some examples, the aerosol generating substrate 12 such as tobacco may be treated with a vaporising agent. The vaporing agent may improve the generation of vapour from the aerosol generating substrate 12. The vaporising agent may include, for example, a polyol such as glycerol, or a glycol such as propylene glycol. In some cases, the aerosol generating substrate 12 may contain no tobacco, or even no nicotine, but instead may contain naturally or artificially derived ingredients for flavouring, volatilisation, improving smoothness, and/or providing other pleasurable effects.

[0041] The aerosol generating substrate 12 may be provided as a solid or paste type material in shredded, pelletised, powdered, granulated, strip or sheet form, optionally a combination of these. Equally, the aerosol generating substrate 12 may be a liquid or gel. Indeed, some examples may include both solid and liquid/gel parts. Indeed, some examples may include both solid and liquid/gel parts. In some examples, the substrate 12 may be a solid block, or may be loose material packed in a wrapper 13. Preferably the substrate comprises randomly oriented tobacco strands containing tobacco powder and an aerosol former. Suitable aerosol formers include: a polyol such as sorbitol, glycerol, and glycols like propylene glycol or triethylene glycol; a non-polyol such as monohydric alcohols, acids such as lactic acid, glycerol derivatives, esters such as triacetin, triethylene glycol diacetate, triethyl citrate, glycerin or vegetable glycerin. In some embodiments, the aerosol generating agent may be glycerol, propylene glycol, or a mixture of glycerol and propylene glycol.

[0042] Whilst the aerosol generating substrate 12 will typically produce a gas or a solid and/or liquid suspension in gas when heated, it will be appreciated that the terms vapour and aerosol are generally used interchangeably here, and refer generally to the substance which is produced when the aerosol generating substrate 12 is heated, to produce a suspension of particles or droplets of any size.

[0043] As used herein, the term fluid shall be construed as generically describing non-solid materials of the type that are capable of flowing, including, but not limited to, liquids, pastes, gels, powders and the like. Fluidized materials shall be construed accordingly as materials which are inherently, or have been modified to behave as, fluids. Fluidization may include, but is not limited to, powdering, dissolving in a solvent, gelling, thickening, thinning and the like.