GB2569966A

GB2569966A - A two-part aerosol production system

Info

Publication number: GB2569966A
Application number: GB1800112.3A
Authority: GB
Inventors: William John McLaughlin David; Robert Hopps Jason
Original assignee: Elucid8 Holdings Ltd
Current assignee: Elucid8 Holdings Ltd
Priority date: 2018-01-04
Filing date: 2018-01-04
Publication date: 2019-07-10
Also published as: GB201800112D0

Abstract

A two-part aerosolisation system comprising separable vaporisation means 4 and flavouring means 8, wherein the vaporisation means (4, fig. 1) has a piercing element 13 that inserts into the flavouring means 8 to co-join the two parts. The aerosolisation system may be an e-cigarette or heat not burn tobacco product wherein the flavouring means 8 contains a tobacco-derived flavouring material 6. The vaporisation means may have at least one element (18, fig. 6) movable from a first position occluding at least one vapour exit hole to a second position. The piercing element 13 preferably conducts a first aerosol (5, fig. 1) from the vaporisation means to the flavouring means 8. The flavouring means 8 may comprise a receiving region 33 for receiving the piercing element 13 wherein the receiving region 33 may be shaped to cause rotational motion about a central longitudinal axis upon conjoining the vaporization means (4, fig. 1) and the flavouring means 8. Upon insertion of the piercing elements 13 through a sealing means (36, fig. 10), the flavouring means 8 may have a weakened region that opens or a movable plug that is displaced.

Description

A two-part aerosol production system

Description

Referring to Figure 1, this invention pertains to the design of a separable vapourisation means 4 and flavouring means 8, intended for use together within hybrid tobacco products .

There are several alternatives to traditional tobacco products which are becoming increasingly popular. Heat-not-burn (HNB) tobacco products typically employ an energy source to heat a tobacco-containing consumable and thereby generate an inhalable aerosol that contains volatile components derived from tobacco, notably flavour and nicotine.

Electronic cigarettes employ an energy source to vapourise a liquid typically comprising a mixture of glycerol, propylene glycol, flavour and nicotine to form an inhalable aerosol.

There are also various "hybrid" products which can combine technology from both electronic cigarettes and heat-not-burn tobacco products to generate an inhalable nicotine-containing aerosol wherein flavour and nicotine can originate from either the aerosol-generating liquid or the tobacco portions or both.

Specific examples of existing technologies include: WO9639880 and W02013190036 describe a cigarette-like cylindrical consumable article, with a distal end containing tobacco-derived material, typically crimped reconstituted tobacco sheet, a mouth-end filter typically containing multiple segments, and an overwrap made from paper. Said article is intended to be electrically heated to produce an inhalable nicotine-containing aerosol. W02016207407 also describes a tobacco consumable intended for consumption by heating, namely a distal tobacco-derived portion, a mouth-end filter and a paper overwrap . W02016159013 describes a device in which an aerosol is generated by heating a liquid which is then passed through a separate tobacco portion; the tobacco portion imparts flavour and/or nicotine to the final aerosol. The tobacco portion can be held within a moulded plastic capsule with a mesh at the distal end and a small filter at the mouth-end. WO2016135342 describes a product which operates in a similar manner to that described in W02016159013, however the tobacco portion and the liquid heating unit are comprised as one unit. The tobacco portion is held within a moulded plastic structure with a filter at the mouth-end.

It is desirable that consumable units can only be used in the devices for which they are intended, for example that the device recognises and will only function with the designated consumable. Various existing technologies include for example : WO2016199066 describes an aerosol generating consumable with a product-identifying article associated with the consumable (for example, RFID tag); and a device configured to receive the consumable with for example, an RFID reader configured to detect the RFID tag. US2017231277 describes a method to identify the liquid aerosol-forming substrate held in a consumable of an electronic cigarette, based on measurement of an electrical quantity such as impedance, resistance or capacitance. US2017055589 describes a method of printing information onto the consumable for an electrically-heated smoking system (for example, using visible ink, ultra violet ink, infrared ink etc.) and a suitable detection system within the device of the electrically-heated smoking system for reading the information printed on the consumable.

However, each of these technologies has certain disadvantages, for example, cost or complexity of manufacture.

The term aerosol shall be interpreted to include gas, vapour, droplets, condensates, particulates and combinations thereof. An inhalable aerosol shall mean an aerosol with an average particle size as measured by laser dispersion ranging from 0.1 to 10 pm, more preferably 0.1 to 1.5 pm.

Referring to Figure 1, a vapourisation means 4 is a system that converts a liquid into an aerosol. It comprises a liquid transport means 2 and a heating means 3. A liquid transport means 2 is in fluid connection with a liquid storage means 1 and a heating means 3. A liquid transport means 2 may be comprised of a wicking material, fibres, tube, tubes, capillaries and combinations thereof.

Also in Figure 1, a flavouring means 8 is an element that imparts sensory enhancement to a first aerosol 5. Preferably a flavouring means comprises an external envelope 7 and a flavouring material 6 which contains volatile compounds which enhance the aerosol. Sensory enhancement may be flavour, aroma, active volatile substance or combination thereof. Active volatile substances are components of plant material or plant extract, or synthetic chemicals, that produce pharmacological or sensorial effects when evaporated/inhaled. Active volatile substances may be extracts of tobacco, nicotine, caffeine, taurine, clove, cannabidiol, menthol and combinations thereof. Sensory enhancement may be derived from a solid, liquid, gel or combinations thereof. Preferably a flavouring means 8 contains a tobacco-derived flavouring material. A heating means 3 is a means to convert electrical energy into heat energy. A heating means 3 may be comprised of a resistive element. A resistive element may be comprised of metal, alloy, ceramic or combinations thereof.

The mouth end 12 is the end of the aerosol production element intended to act as an exit for an inhalable aerosol 9 towards the user. The distal end 11 of the flavouring means 8 is the end intended to act as an entry point for air and other materials to flow in. The longitudinal axis 10 runs from the distal end to the mouth end. Other axes are taken as perpendicular to the longitudinal axis.

Hybrid products typically produce a first aerosol 5 by heating an e-liquid often containing glycerol and propylene glycol using a vapourisation means 4. This first aerosol 5 is then passed through a region of tobacco or tobacco-derived flavouring material within a flavouring means 8 to produce a final inhalable aerosol 9 which is inhaled by the user. Often hybrid products utilise a non-flavoured, zero nicotine e-liquid to produce the first aerosol 5 and hence rely upon the entrainment of volatile compounds from the tobacco portion to provide desirable taste and sensorial attributes to the inhalable aerosol 9.

Within the consumable portion of hybrid products, the vapourisation means 4 to produce the first aerosol 5, and the flavouring means 8 can be supplied as a single integral unit (for example, Figure 5) . In an alternative arrangement, the vapourisation means 4 and the flavouring means 8 are separable (for example, Figures 2 & 3), which has the advantage that the two units can be replaced independently, giving more flexibility.

In hybrid products, the heating process to generate the first aerosol 5 is separate from the entrainment process which imparts flavour and nicotine to the inhalable aerosol 9. A lack of heating during the entrainment process places a number of limitations upon the efficiency of the entrainment process, which in turn negatively affects the desirability of the inhalable aerosol 9.

As described elsewhere, by minimising the distance between the heating means 3 and the tobacco-derived flavouring material 6, significantly more of the total heat energy generated in the vapourisation process can be transferred to the tobacco-derived flavouring material and used to drive off volatile components to be entrained into the final inhalable aerosol 9. Hence it is desirable to have the vapourisation means positioned within the flavouring means 8. Most preferably the heating means 3 is positioned centrally within the flavouring material 6 to make best use of the generated heat energy.

When the flavouring means 8 is a separate consumable it is difficult for the consumer to introduce the vapourisation means 4 into the correct position within the flavouring means 8 to have efficient entrainment. The current invention overcomes these limitations by providing a robust vapourisation means 4 sufficient to penetrate the flavouring means 8 and a receiving region within the flavouring means 8 to guide correct insertion.

To assist the correct conjoining of the separable flavouring means 8 to the vapourisation means 4 it is beneficial to have a shaped receiving region within the flavouring means 8. A shaped receiving region can act as a guide to position the vapourisation means 4 in the desired position within the flavouring means 8, preferably centrally.

Figure 10 shows a preferred embodiment of flavouring means 8. A circular aperture 31 at the distal end leads into a conical indentation 32. In this embodiment, flavouring means 8 is separate from, and intended for insertion into the receiving portion 35 of the vapourisation means in Figure 11. Upon insertion of flavouring means 8 into housing 35, piercing element 13 is guided through aperture 31 and cavity 32, and displaces region 33, until piercing element 13 reaches its optimal position within tobacco-derived flavouring material 6a of flavouring means 8. The region 33 may be easily punctured by the piercing element 13, whilst leaving the surrounding region intact. Alternatively, this region 33 may be separable from the surrounding material and is displaced upon insertion of the piercing element 13. Region 33 may be formed from a different material than that of filter material 6 such as a wax.

The receiving region of the flavouring means 8 optionally may have an additional hermetic seal 36 which is punctured by the piercing element 13. Preferably this seal is moisture and air impermeable. Most preferably the seal is an aluminium foil.

As shown in Figure 2, a separable flavouring means typically has porous barriers 15 at the ends, to allow aerosol to pass through, but to prevent tobacco-derived flavouring material 6a from falling out or being inhaled. Such porous barriers 15 can be comprised of plastic mesh or cellulose acetate filters, and provide filtration processes which negatively affect the amount of inhalable aerosol 9 available to the consumer. Hence a further benefit of the present invention is that having a vapour exit from the vapourisation means 4 within the tobacco portion removes any potential filtration processes between the heating means 3 and the tobacco portion 6 as can be found with typical separable flavouring means.

To assist the conjoining, the vapourisation means 4 may have a robust piercing element which is inserted into the flavouring means. Figure 9 shows alternative embodiments of the piercing element 13. Cross-section 24 of piercing element 13 can be substantially cylindrical 26, substantially elliptical 25 or substantially rectangular 27, or any combinations thereof along its length. The holes through which aerosol emerges from piercing element 13 can be of various shapes and locations. For example, there may be a single hole 28 at the end of piercing element 13. Alternatively, there may be more than one hole 29 along the side walls of piercing element 13, which can be formed at an angle 23 relative to the longitudinal axis 10. Depending on angle 23, first aerosol 5 exiting from holes 29/30 may be directed along the most efficient path through tobacco-derived flavouring material 6a so as to optimise entrainment. Holes can be of differing size 30 to aid more consistent dispersion of aerosol into tobacco-derived flavouring element 6a.

In the preferred embodiment illustrated in Figure 3, the piercing element 13 extends down the receiving portion 35 of any external housing intended to receive the flavouring means 8. By thus extending the piercing element 13 it prevents the conjoining of the separable flavouring element 8 without inserting the piercing means 13 into the flavouring means 8 and correct positioning of the vapour exits within the flavouring material and desirable entrainment of volatile components. Preferably the piercing means 13 extends to within 10mm of the external opening. Most preferably the piercing means 13 extends to within less than 5mm of the external opening.

For systems employing separable vapourisation means 4 and flavouring means 8, it is undesirable to be able to operate the vapourisation means 4 in the absence of the flavouring means 8. To prevent this unintended use, the piercing element 13 of vapourisation means 4 can be preferably equipped with a movable element 18, as shown in Figure 6. The movable element 18 has at least two positions. In the first position (Figure 6) the movable element 18 at least partly occludes at least one vapour exit hole 19 in the piercing element 13, thus preventing the user from inhaling the first aerosol 5. Preferably in the first position the movable element 18 completely occludes all vapour exit holes 19. In a second position (Figure 7) the holes 19 in the piercing element 13 and holes 20 in the movable element 18 align, and permit aerosol to flow in direction 22 into the tobacco-derived flavouring material 6a.

It is preferable that the action of bringing together the flavouring means 8 and the vapourisation means 4 moves the movable element 18 from the first position to the second position, thereby allowing the first aerosol 5 to pass through the flavouring means 8 to become the inhalable aerosol 9. Preferably the movable element has at least one region which is acted upon by the flavouring means to move the movable element. This region can be in the form of a flange at the distal end, a region of wider circumference, a raised portion, a protrusion or combinations thereof.

Preferably the movable element 18 has a biasing element 21, which acts to return the movable element 18 to its first position upon removal of the flavouring means 8. Preferably the biasing element 21 is a spring.

The current invention, through use of non-electronic methods, offers various advantages over the prior art for compatibility of consumable units with electronic cigarette, hybrid, heat-not-burn and other such devices, namely:

Ease of manufacture, and potentially reduced cost

The device cannot be used unless fully assembled with the designated consumable, which prevents unintended consumption of inhalable aerosols for which the unit was not designed. Furthermore, this may make use of the product less accessible for children (i.e., "child-resistance")

Reduces the likelihood of the consumable being used in alternative devices for which it is not intended

Reduces the likelihood of the device being used with other consumables for which they are not intended

Piercing element 13 may also function to break through hermetic seals integral to the consumable unit, thus reducing the need for separate outer packaging, which in turn may reduce pack size and product cost

In a preferred embodiment of the present invention, Figure 2, the heating means 3 is positioned within the tobacco-derived flavouring material 6a, thus heat energy that would otherwise lost to the surroundings via the external walls is absorbed by the tobacco-derived material 6a. Heating means 3 is contained within, and where necessary electrically insulated from, a piercing element 13. Piercing element 13 may be a cylinder composed of stainless steel, and also carries electrical connector wires 14, and liquid transporting means 2 which carries e-liquid from reservoir 1 to heat source 3. Most preferably the heat source is positioned centrally within the tobacco-derived flavouring material so that heat losses to the environment in all directions are minimised.

Heat losses to the environment can also be minimised by the use of an insulation region 16 between the tobacco-derived flavouring material 6a and the external environment. In a preferred embodiment, Figure 3, the consumable flavouring means 8 fits inside a receiving portion 35 of a reusable device. The region of the device that immediately surrounds the consumable is insulated 16, thereby retaining heat energy within the flavouring means. Most preferably, the insulation 16 is a composite of aluminium foil and a dense polyurethane foam with thermal conductivity less than or equal to 0.03W/(m K).

The tobacco-derived flavouring material can include single-grade tobacco, blended tobacco grades, leaf, stem, dust, reconstituted tobacco, washed tobacco, extracted tobacco, treated tobacco, tobacco extracts and mixtures thereof. The tobacco-derived flavouring material can be produced from tobacco plants by methods including harvesting, drying, cutting, shredding, grinding, extraction, reconstitution, extrusion and combinations thereof. The tobacco-derived flavouring material can be present in the physical form of leaf, stem, dust, reconstituted sheet, crimped, folded, shaped, beaded, granulated and mixtures thereof.

In a preferred embodiment, the tobacco-derived flavouring material is presented in the form of regularly sized granules or beads. Such tobacco containing granules are preferably produced by extrusion.

In an alternate preferred embodiment, the tobacco-derived flavouring material is presented in the form of folded reconstituted sheet material 6c arranged in a radial pattern, as shown in Figure 5. This arrangement provides a high surface area within a defined structure, which has the benefit of producing a consistent entrainment into the first aerosol 5. It also ensures that the first aerosol 5 must pass through the tobacco-derived flavouring material 6c. Heat source 3 is wrapped around liquid-transporting means 2, which are contained within the structure of tobacco sheet material 6c.

To prevent too high a pressure drop from occurring in this radial arrangement of sheet material 6c, it is preferable to have perforations within the sheet material which act as paths of lower resistance for the aerosol to travel. Perforations can be introduced as holes created in the material by mechanical means such as pins, punches, knives; by using jets of fluid such as air or water or combinations thereof. Perforations may be introduced during the manufacture of the sheet material or post manufacture or a combination thereof. Preferably perforations are introduced to increase the average porosity of the sheet material above 5000 CORESTA units (CU). Using such a porous sheet ensures the aerosol can travel in a direction perpendicular to the main axis of the sheet material. A preferred embodiment of the present invention is shown in Figure 8. A vapourisation means 4 comprising a stainless steel outer housing 35, a liquid transport means 2 composed of a 2mm diameter bundle of glass fibres of individual diameter <10pm, a heating means 3 comprising a helical coil of an 80:20 nickel/chromium alloy resistive heating wire of resistance 1Ω insulated electrically by a layer of polyimide. The heating means 3 is housed within a cylindrical stainless-steel piercing element 13 of wall thickness 0.5mm within a cylinder of tobacco-derived flavouring material 6a. The tobacco-derived flavouring material 6a is contained within a cylinder of polyurethane with thermal coefficient of 0.03 W/(mK) with an outer layer of aluminium foil 25pm, finished in a transparent layer of PET.

In this preferred embodiment the flavouring means 8 is comprised of tobacco derived flavouring material held in the cavity formed between two cellulose acetate filter segments and a paper overwrap as described in UK patent application GB1708331.2. The filter segment at the distal end of the flavouring means has a receiving region with a conical indentation 32 having a wider distal end to guide the piercing means 13 into a central position within the flavouring material. This conical indentation is formed by pressing a mandrill in to the end of the filter section during filter manufacture. The distal filter segment has a weakened region positioned centrally that is opened by the piercing means. This weakened region is formed by lasering the cellulose acetate filter segment in the longitudinal direction at 60% power level relative to hole formation. Prior to use the distal end of the flavouring means is covered with an aluminium foil based tri-laminate seal (PP/A1/PP) which is pierced by the piercing element.

In a preferred embodiment, the liquid used is a mixture of 75% propylene glycol and 25% glycerol, with no added flavours or nicotine.

In a preferred embodiment of the present invention, the tobacco-derived portion is generated by providing a blend of tobacco grades comprising flue cured and air-cured tobaccos with a chemical composition in accordance to Gothiatek® Standard, namely tobacco-specific nitrosamine (NNN + NNK) content of <lmg/kg and benzo[a]pyrene content of <1.25ug/Kg. Once blended, the tobacco is reduced in size by first shredding and then grinding to pass through a No.18 Mesh giving a particle size of =<lmm. To the ground tobacco is added 50% equivalent mass of deionised water; 2% equivalent mass of flavourant - a 50:50 mix of menthol and mint oils; 0.375% equivalent mass pH modifying agent - sodium hydroxide. The resultant tobacco paste is passed through a Coperion extruder with barrel temperature 250°C and pressure 4atm linked to a pelletizer to produce a shaped material of particle size approximately 1.5mm diameter. The tobacco-derived particles are then dried under vacuum to <10% moisture. The dried tobacco particles are then sieved to produce a fraction in the range 0.2mm ~ 1.25mm.

Figure 5 shows an alternative preferred embodiment where the tobacco-derived flavouring material is in the form of a folded sheet 6c. In this embodiment, the tobacco sheet 6c is formed using the same input tobacco and initial processing as outlined above, but is ground such that it will pass through a No.35 Mesh / ^0.5mm particle size. 6% cellulose fibres are added to the flavoured tobacco mix prior to addition of the base. After the addition of the sodium hydroxide, the resultant tobacco paste is then spread out to form a layer of thickness 0.5mm and dried using infra-red heating to a moisture of 15%~20%. The porosity of this material is increased to 12,500CU by using a series of pin rollers to generate holes of average diameter 0.1mm. This sheet material is then folded to form a pleated structure of height 3mm. The pleated sheet is then further dried to a final moisture of 10%.

Figure 4 shows a cross-section of an alternative embodiment where the heating means 3a and tobacco-derived flavouring material 6b are substantially planar and in close contact. Heating means 3a may be a porous membrane comprised of nichrome wire embedded in polyimide, or a porous stainless-steel foil. The liquid transport means 2 is a 3mm layer of wicking material, preferably Japanese cotton. The tobacco-derived flavouring material 6b comprises tobacco-derived sheet material prepared as described previously, arranged in a stack of multiple layers, preferably at least 5 layers. The tobacco-derived flavouring material 6b is porous to allow the passage of aerosol perpendicular to the orientation of the sheet. Preferably the tobacco sheet material has a porosity of 1250CU with an average hole diameter of 0.1mm.

During use, heating means 3a evaporates e-liquid from liquid transport means 2, and air is drawn in direction of arrow 17, which carries aerosol particles through pores in tobacco-derived flavouring material 6b, wherein volatile components from the tobacco-derived flavouring material 6b become associated with aerosol particles, forming inhalable aerosol 9.

Claims

1. A two-part aerosolisation system comprising a separable vapourisation means and flavouring means wherein the vapourisation means has a piercing element that inserts into the flavouring means to co-join the two parts .

2. A two-part aerosolisation system according to claim 1 that when the vapourisation means and flavouring means are co-joined the heating means is <5mm from the flavouring material.

3. A two-part aerosolisation system according to any preceding claim that when the vapourisation means and flavouring means are co-joined the temperature drop during use from heating means to the flavouring material is less than 100°C.

4. A vapourisation means according to any preceding claim that has at least one element movable from a first position to a second position, the first position occluding at least one vapour exit hole.

5. A vapourisation means according to any preceding claim wherein the movable element has at least one region acted upon by the flavouring means to move the movable element from a first position to a second position upon co-joining the vapourisation means and the flavouring means .

6. A vapourisation means according to any preceding claim wherein the movable element has a biasing element which acts to return the movable element to the first position upon separation of the co-joined flavouring means and vapourisation means.

7. A piercing element according to any preceding claim that conducts the first aerosol from the vapourisation means to the flavouring means .

8. A vapourisation means according to any preceding claim that has a wider axis in the cross direction and a least one vapour exit hole positioned on the wide surface.

9. A vapourisation means according to any preceding claim that extends to within 5mm of the receiving opening of any external device housing.

10. A flavouring means according to any preceding claim that has a receiving region shaped to receive the piercing element.

11. A receiving region within the flavouring means according to any preceding claim that is wider in the cross direction at the distal end and reduces in size towards the mouth end.

12 . A receiving region within the flavouring means according to any preceding claim shaped to cause rotational motion about a central longitudinal axis upon conjoining the vapourisation means and the flavouring means .

13. A flavouring means according to any preceding claim that has a weakened region that opens upon insertion of the piercing element of the vapourisation means .

14. A flavouring means according to any preceding claim that has a movable plug that is displaced upon insertion of the piercing element of the vapourisation means.

15. A flavouring means according to any preceding claim that has a sealing means which is penetrated by the piercing element of the vapourisation means .