Aerosol generating articles and methods for manufacturing the same

Abstract

A sheet-type aerosol generating article includes at least two aerosol generating sheets each having aerosol generating material and an inductively heatable susceptor The inductively heatable susceptor is positioned between the aerosol generating sheets and each of the aerosol generating sheets has an exposed surface. Methods for manufacturing sheet-type aerosol generating articles are also disclosed.

Claims

1. An aerosol generating article comprising: at least two aerosol generating sheets each comprising aerosol generating material; and an inductively heatable susceptor; wherein the inductively heatable susceptor is positioned between two of the at least two aerosol generating sheets and each of the at least two aerosol generating sheets has an exposed surface, and further including perforations which extend through the article.

2. The aerosol generating article according to claim 1, wherein the inductively heatable susceptor comprises a sheet of susceptor material separating two of the at least two aerosol generating sheets.

3. The aerosol generating article according to claim 2, wherein an edge region of the sheet of susceptor material is covered by a stretched or deformed edge region of at least one of the at least two aerosol generating sheets.

4. An aerosol generating article comprising: at least two aerosol generating sheets each comprising aerosol generating material; and an inductively heatable susceptor; wherein the inductively heatable susceptor is positioned between two of the at least two aerosol generating sheets and each of the at least two aerosol generating sheets has an exposed surface, and wherein the inductively heatable susceptor comprises a plurality of strips of susceptor material.

5. The aerosol generating article according to claim 1, wherein the inductively heatable susceptor comprises a particulate susceptor material.

6. The aerosol generating article according to claim 1, further comprising a further layer or sheet covering each of the at least two aerosol generating sheets, the further layer or sheet comprising a material which differs from the aerosol generating material and a material of the inductively heatable susceptor.

7. The aerosol generating article according to claim 1, wherein the at least two aerosol generating sheets are adhered to each other by an adhesive.

8. The aerosol generating article according to claim 7, wherein a layer of the adhesive is disposed between two of the at least two aerosol generating sheets, and the inductively heatable susceptor is provided in the adhesive layer.

9. A method for manufacturing an aerosol generating article comprising: (i) positioning an inductively heatable susceptor between two aerosol generating sheets each comprising aerosol generating material, each of the aerosol generating sheets having an exposed surface; and (ii) perforating the two aerosol generating sheets and the susceptor positioned therebetween, forming perforations that extend through the article.

10. The method according to claim 9, wherein the two aerosol generating sheets are continuous sheets and the method further comprises: (iii) cutting the continuous sheets with the susceptor positioned therebetween.

11. The method according to claim 10, wherein the inductively heatable susceptor is a continuous susceptor and step (iii) comprises simultaneously cutting the continuous sheets and the continuous susceptor positioned therebetween.

12. The method according to claim 9, wherein step (i) comprises positioning the inductively heatable susceptor on a first one of said two aerosol generating sheets and positioning a second one of said two aerosol generating sheets on the susceptor.

13. The method according to claim 9, wherein step (i) comprises: mixing the inductively heatable susceptor with an adhesive to form a mixture; and positioning the mixture on a first one of said two aerosol generating sheets.

14. The method according to claim 9, wherein step (i) comprises: positioning an adhesive on a first one of said two aerosol generating sheets; and positioning the inductively heatable susceptor on the adhesive.

15. The method according to claim 9, wherein the method further comprises pressing the two aerosol generating sheets and the inductively heatable susceptor positioned therebetween to thereby bond the two aerosol generating sheets.

16. The method according to claim 9, wherein the inductively heatable susceptor comprises a continuous sheet of susceptor material.

17. The method according to claim 9, wherein the inductively heatable susceptor comprises a continuous sheet of susceptor material and the method comprises deforming or stretching an edge region of at least one of the two aerosol generating sheets to cover an edge region of the sheet of susceptor material.

18. The aerosol generating article according to claim 1, wherein the at least two aerosol generating sheets are adhered to the inductively heatable susceptor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagrammatic cross-sectional view of a first example of an aerosol generating article;

(2) FIG. 2 is a diagrammatic cross-sectional view of a second example of an aerosol generating article similar to the first example shown in FIG. 1;

(3) FIG. 3 is a diagrammatic view of the second example of the aerosol generating article in the direction of arrow A in FIG. 2;

(4) FIG. 4 is a diagrammatic cross-sectional view of a third example of an aerosol generating article similar to the second example shown in FIGS. 2 and 3;

(5) FIGS. 5a and 5b are diagrammatic cross-sectional and top views respectively of an aerosol generating device for use with aerosol generating articles according to the present disclosure;

(6) FIG. 5c is a diagrammatic cross-sectional view of a mouthpiece for use with the aerosol generating device of FIGS. 5a and 5b;

(7) FIG. 6a is a diagrammatic view of an apparatus and method for manufacturing the first example of the aerosol generating article shown in FIG. 1;

(8) FIGS. 6b and 6c are diagrammatic illustrations of one example of a cutter used in the apparatus and method of FIG. 6a;

(9) FIG. 7 is a diagrammatic view of an apparatus and method for manufacturing the third example of the aerosol generating article shown in FIG. 4;

(10) FIG. 8 is a diagrammatic view of an alternative apparatus and method for manufacturing the third example of the aerosol generating article shown in FIG. 4;

(11) FIG. 9 is a diagrammatic view of an apparatus and method for manufacturing a fourth example of an aerosol generating article; and

(12) FIG. 10 is a diagrammatic view of an apparatus and method for manufacturing a fifth example of an aerosol generating article.

DETAILED DESCRIPTION OF EMBODIMENTS

(13) Embodiments of the present disclosure will now be described by way of example only and with reference to the accompanying drawings.

(14) Referring initially to FIG. 1, there is shown a first example of an aerosol generating article 1 for use with an aerosol generating device, an example of which will be described later in this specification. The aerosol generating article 1 is elongate and has a sheet-type form which, amongst other things, facilitates handling of the article 1 by a user and insertion of the article 1 into a heating compartment of an aerosol generating device.

(15) The aerosol generating article 1 comprises first and second aerosol generating sheets 10, 12 each comprising aerosol generating material 14. The aerosol generating material 14 is typically a solid or semi-solid material. Examples of suitable aerosol generating solids include powder, shreds, strands, porous material or foam material. The aerosol generating material typically comprises plant derived material and, in particular, comprises tobacco. The aerosol generating material 14 may alternatively comprise an aerosol generating liquid impregnated into or absorbed by a liquid absorbent material forming the aerosol generating sheets 10, 12.

(16) The aerosol generating article 1 comprises an inductively heatable susceptor 16 having a thickness which is preferably less than the thickness of the aerosol generating sheets 10, 12. The inductively heatable susceptor 16 is positioned between the first and second aerosol generating sheets 10, 12 and is inductively heatable in the presence of a time varying electromagnetic field. In the illustrated first example, the inductively heatable susceptor 16 comprises a sheet of susceptor material 18 which separates, and is adhered to, the first and second aerosol generating sheets 10, 12 by a substantially non-electrically conductive and non-magnetically permeable adhesive.

(17) When a time varying electromagnetic field is applied in the vicinity of the inductively heatable susceptor 16 during use of the article 1 in an aerosol generating device, heat is generated in the inductively heatable susceptor 16 due to eddy currents and magnetic hysteresis losses and the heat is transferred from the inductively heatable susceptor 16 to the adjacent first and second aerosol generating sheets 10, 12 to heat the aerosol generating material 14 without burning it and to thereby generate an aerosol for inhalation by a user. The inductively heatable susceptor sheet 18 is in contact over its entire surfaces with the adjacent first and second aerosol generating sheets 10, 12, thus enabling heat to be transferred directly, and therefore efficiently, from the inductively heatable susceptor sheet 18 to the aerosol generating material 14.

(18) The aerosol generating material 14 of the first and second aerosol generating sheets 10, 12 comprises at least one aerosol-former such as glycerine or propylene glycol.

(19) Typically, the aerosol generating material 14 may comprise an aerosol-former content of between approximately 5% and approximately 50% on a dry weight basis. Upon heating due to heat transfer from the inductively heatable susceptor sheet 18, the aerosol generating material 14 of both the first and second aerosol generating sheets 10, 12 releases volatile compounds possibly including nicotine or flavour compounds such as tobacco flavouring. Each of the aerosol generating sheets 10, 12 has an exposed surface 10a, 12a thus ensuring that the generated aerosol can be easily released.

(20) Referring now to FIGS. 2 and 3, there is shown a second example of an aerosol generating article 2 which is similar to the aerosol generating article 1 illustrated in FIG. 1 and in which corresponding elements are designated using the same reference numerals.

(21) The aerosol generating article 2 is identical to the aerosol generating article 1 illustrated in FIG. 1 in all respects and in addition comprises a further layer or sheet 20, 22 covering each of the first and second aerosol generating sheets 10, 12. The further layer or sheet 20, 22 comprises a material which differs from the aerosol generating material 14 and the material of the inductively heatable susceptor sheet 18 and is provided to facilitate handling of the aerosol generating article 2 by a user. The further layer or sheet 20, 22 typically comprises a material which is non-electrically conductive and non-magnetically permeable so that it is not heated in the presence of a time-varying electromagnetic field during use of the article 2 in an aerosol generating device. In typical embodiments, the further layer or sheet 20, 22 comprises paper.

(22) The further layer or sheet 20, 22 is air-permeable to facilitate the release of generated aerosol from the first and second aerosol generating sheets 10, 12. As best seen in FIG. 3, the further layer or sheet 20, 22 comprises a plurality of openings 24 across its surface which expose the surfaces 10a, 10b of the aerosol generating sheets 10, 12 and provide the further layer or sheet 20, 22 with the desired level of air permeability.

(23) Referring now to FIG. 4, there is shown a diagrammatic cross-sectional view of a third example of an aerosol generating article 3 which is similar to the aerosol generating article 2 illustrated in FIGS. 2 and 3 and in which corresponding elements are designated using the same reference numerals.

(24) The aerosol generating article 3 is identical to the aerosol generating article 2 illustrated in FIGS. 2 and 3 in all respects except that the inductively heatable susceptor 16 comprises a plurality of strips or particles of susceptor material 26 positioned in an adhesive layer 28 between the first and second aerosol generating sheets 10, 12. It will be seen in FIG. 4 that the adhesive layer 28 contacts the first and second aerosol generating sheets 10, 12 and thereby securely adheres them to each other.

(25) Referring now to FIGS. 5a to 5c, there is shown an example of an aerosol generating device 30 for use with the aerosol generating articles 1, 2, 3 described above for generating an aerosol to be inhaled.

(26) The aerosol generating device 30 has a proximal end 32 and a distal end 34 and comprises a device body 36 which includes a power source 38 and a controller 40 which may be configured to operate at high frequency. The power source 38 typically comprises one or more batteries which could, for example, be inductively rechargeable.

(27) The aerosol generating device 30 comprises an aerosol generating space 42, for example in the form of a heating compartment, accessible from the proximal end 32 of the aerosol generating device 30. The aerosol generating space 42 has a rectangular cross-section as best seen in FIG. 5b and is arranged to receive a correspondingly shaped sheet-type aerosol generating article 1, 2, 3 as described above.

(28) The aerosol generating device 30 comprises a helical induction coil 44 which has a circular cross-section and which extends around the aerosol generating space 42. The induction coil 44 can be energised by the power source 38 and controller 40. The controller 40 includes, amongst other electronic components, an inverter which is arranged to convert a direct current from the power source 38 into an alternating high-frequency current for the induction coil 44.

(29) The aerosol generating device 30 includes an air inlet 46 in the device body 36 which allows ambient air to flow into the aerosol generating space 42. The aerosol generating device 30 also includes a mouthpiece 48 having an air outlet 50. The mouthpiece 48 is removably mountable on the device body 36 at the proximal end 32 to allow access to the aerosol generating space 42 for the purposes of inserting or removing a sheet-type aerosol generating article 1, 2, 3 as described above.

(30) As will be understood by one of ordinary skill in the art, when the induction coil 44 is energised during use of the aerosol generating device 30, an alternating and time-varying electromagnetic field is produced. This couples with the inductively heatable susceptor 16 of an aerosol generating article 1, 2, 3 positioned in the aerosol generating space 42 and generates eddy currents and/or magnetic hysteresis losses in the inductively heatable susceptor 16 causing it to heat up. The heat is then transferred from the inductively heatable susceptor 16 to the aerosol generating material 14 of the first and second aerosol generating sheets 10, 12, for example by conduction, radiation and convection, to heat the aerosol generating material 14 and thereby generate an aerosol.

(31) The aerosolisation of the aerosol generating material 14 is facilitated by the addition of air from the surrounding environment through the air inlet 46. The aerosol generated by heating the aerosol generating material 14 in the first and second aerosol generating sheets 10, 12 exits the aerosol generating space 42 through the air outlet 50 in the mouthpiece 48 where it can be inhaled by a user of the device 30. The flow of air through the aerosol generating space 42, i.e. from the air inlet 46, through the aerosol generating space 42 and out of the air outlet 50, can be aided by negative pressure created by a user drawing air from the air outlet 50 side of the device 30.

(32) Examples of apparatus and methods for manufacturing aerosol generating articles in accordance with the present disclosure will now be described with reference to FIGS. 6 to 10.

(33) Referring initially to FIG. 6a, there is shown a diagrammatic illustration of an apparatus 60 and method for manufacturing the first example of the aerosol generating article 1 described above with reference to FIG. 1.

(34) The apparatus 60 comprises first and second supply reels 62, 64 each carrying first and second aerosol generating sheets 10, 12 in continuous sheet form and a third supply reel 66 carrying an inductively heatable susceptor 16 in the form of a continuous sheet 18. The apparatus 60 also comprises first and second adhesive applicators 68, 70, such as nozzles, and a cutter 72.

(35) The first aerosol generating sheet 10 is supplied from the first supply reel 62 and a first adhesive layer 74 is applied to a surface of the first aerosol generating sheet 10 by the first adhesive applicator 68. The continuous sheet 18 of inductively heatable susceptor 16 is supplied from the third supply reel 66 and is pressed into contact with the first adhesive layer 74 by a press roller 78 before a second adhesive layer 76 is applied to a surface of the continuous sheet 18 of inductively heatable susceptor 16 by the second adhesive applicator 70. The second aerosol generating sheet 12 is then supplied from the second supply reel 64 and is pressed into contact with the second adhesive layer 76 by a press roller 80 to produce a continuous sheet-type article. Finally, the continuous sheet-type article is cut at appropriate positions by the cutter 72 into predetermined lengths to form multiple sheet-type aerosol generating articles 1. It will be understood that this type of method is suitable for the mass production of aerosol generating articles 1.

(36) FIGS. 6b and 6c illustrate an example of the cutter 72 which comprises first and second cutting members 130, 132 (note that the first and second adhesive layers 74, 76 are omitted from these figures for clarity). The first and second cutting members 130, 132 each have a sharp cutting edge 134 and concave curved portions 136 which extend away from the cutting edge 134.

(37) In order to cut the continuous sheet-type article at appropriate positions into predetermined lengths to form multiple sheet-type aerosol generating articles 1, the first and second cutting members 130, 132 are moved towards each other to bring the cutting edges 134 into contact as shown in FIG. 6c. During movement of the first and second cutting members 130, 132 towards each other, it will be seen from FIG. 6c that the edge regions of the aerosol generating sheets 10, 12 are deformed, for example stretched, by the concave curved portions 136 of the first and second cutting members 130, 132 to cover and enclose corresponding edge regions of the inductively heatable susceptor sheet 18. The deformation of the edge regions of the aerosol generating sheets 10, 12 is facilitated because the thickness of the aerosol generating sheets 10, 12 is greater than the thickness of the inductively heatable susceptor sheet 18.

(38) Referring now to FIG. 7, there is shown a diagrammatic illustration of an apparatus 90 and method for manufacturing the third example of the aerosol generating article 3 described above with reference to FIG. 4.

(39) The apparatus 90 comprises first and second supply reels 62, 64, a press roller 80 and a cutter 72 as described above. The apparatus 90 additionally comprises a mixer 92 for mixing together an inductively heatable susceptor 16, for example comprising a plurality of particles of susceptor material 26, and an adhesive 28 to form an adhesive/particulate mixture 96 which is stored in a hopper 94.

(40) The first aerosol generating sheet 10 is supplied from the first supply reel 62 and the adhesive/particulate mixture 96 is applied to a surface of the first aerosol generating sheet 10 by an applicator associated with the hopper 94. The second aerosol generating sheet 12 is then supplied from the second supply reel 64 and is pressed into contact with the adhesive/particulate mixture 96 by the press roller 80 to produce a continuous sheet-type article in which the first and second aerosol generating sheets 10, 12 are secured together by the adhesive layer 28. Finally, the continuous sheet-type article is cut at appropriate positions by the cutter 72 into predetermined lengths to form multiple sheet-type aerosol generating articles 3. This type of method is suitable for the mass production of aerosol generating articles 3 and is particularly convenient if the particles of susceptor material 26 have relatively small dimensions.

(41) Referring now to FIG. 8, there is shown a diagrammatic illustration of an alternative apparatus 100 and method for manufacturing the third example of the aerosol generating article 3 described above with reference to FIG. 4.

(42) The apparatus 100 comprises first and second supply reels 62, 64, a press roller 80 and a cutter 72 as described above. The apparatus 90 additionally comprises an adhesive applicator 102 and a hopper 104 containing a supply of particles of susceptor material 26.

(43) The first aerosol generating sheet 10 is supplied from the first supply reel 62 and an adhesive layer 28 is applied to a surface of the first aerosol generating sheet 10 by the adhesive applicator 102. The particles of susceptor material 26 are then supplied from the hopper 104 onto the previously deposited adhesive layer 28 before the second aerosol generating sheet 12 is then supplied from the second supply reel 64 and is pressed into contact with the adhesive layer 28 containing the particles of susceptor material 26 by the press roller 80 to produce a continuous sheet-type article. Finally, the continuous sheet-type article is cut at appropriate positions by the cutter 72 into predetermined lengths to form multiple sheet-type aerosol generating articles 3. It will again be understood that this type of method is suitable for the mass production of aerosol generating articles 3 and allows carefully controlled deposition of the particles of susceptor material 26 onto the previously deposited adhesive layer 28, for example at predetermined positions or in a predetermined pattern.

(44) Referring now to FIG. 9, there is shown a diagrammatic illustration of an apparatus 110 and method for manufacturing a fourth example of an aerosol generating article.

(45) The apparatus 110 comprises first and second supply reels 62, 64, a hopper 104 containing a supply of particles of susceptor material 26, first and second cooperating nip rollers 112, 114 and a cutter 72.

(46) The first aerosol generating sheet 10 is supplied from the first supply reel 62 and particles of susceptor material 26 are then deposited from the hopper 104 onto a surface of the first aerosol generating sheet 10. The second aerosol generating sheet 12 is then supplied from the second supply reel 64 and the first and second aerosol generating sheets 10, 12 with the particles of susceptor material 26 positioned therebetween are pressed firmly together by the cooperating nip rollers 112, 114. The pressure applied by the nip rollers 112, 114 is sufficient to bond the first and second aerosol generating sheets 10, 12 together with the particles of induction heatable susceptor 26 positioned therebetween. Finally, the continuous sheet-type article is cut at appropriate positions by the cutter 72 into predetermined lengths to form multiple sheet-type aerosol generating articles. It will again be understood that this type of method is suitable for the mass production of aerosol generating articles and advantageously allows the articles to be manufactured without the use of an adhesive.

(47) Referring now to FIG. 10, there is shown a diagrammatic illustration of an apparatus 120 and method for manufacturing a fifth example of an aerosol generating article which is similar to the first example of the aerosol generating article 1 illustrated in FIG. 1.

(48) The apparatus 120 comprises first and second supply reels 62, 64 each carrying first and second aerosol generating sheets 10, 12 in continuous sheet form and a third supply reel 66 carrying an inductively heatable susceptor 16 in the form of a continuous sheet 18. The apparatus 120 also comprises first and second cooperating nip rollers 112, 114, first and second cooperating perforating rollers 122, 124 and a take up bobbin 126.

(49) The first and second aerosol generating sheets 10, 12 are supplied from the first and second supply reels 62, 64 and are positioned on opposite sides of the inductively heatable susceptor sheet 18 supplied from the third supply reel 66. The first and second aerosol generating sheets 10, 12 with the inductively heatable susceptor sheet 18 positioned therebetween are then pressed firmly together as they are fed through the cooperating nip rollers 112, 114. The pressure applied by the nip rollers 112, 114 is sufficient to secure together the first and second aerosol generating sheets 10, 12 and the inductively heatable susceptor sheet 18 to form a sandwich of the sheets 10, 12, 18. The nip rollers 112, 114 can also be heated if desired so that the sheets 10, 12, 18 are pressed together at an elevated temperature.

(50) The continuous sandwich formed by the sheets 10, 12, 18 is then passed through the perforating rollers 122, 124. The perforating rollers 122, 124 include formations which perforate the aerosol generating sheets 10, 12 and the inductively heatable susceptor sheet 18 positioned therebetween so that the sandwich formed by the sheets 10, 12, 18 includes perforations which extend fully through the sheets 10, 12, 18. The size and distribution of the perforations can be carefully controlled by appropriate design of the formations on the perforating rollers 122, 124 to enable the air permeability of the sheets 10, 12, 18, and of the resultant aerosol generating articles, to be likewise carefully controlled and optimised. The formations on the perforating rollers 122, 124 can also be designed and configured so that when the continuous sandwich formed by the sheets 10, 12, 18 is passed through the perforating rollers 122, 124, the edge regions (including around each of the perforations) of the aerosol generating sheets 10, 12 are deformed, for example stretched, to cover and enclose corresponding edge regions of the inductively heatable susceptor sheet 18.

(51) The continuous sandwich formed by the perforated sheets 10, 12, 18 is finally wound onto the take up bobbin 126. The bobbinized sandwich formed by the perforated sheets 10, 12, 18 can subjected to further processing operations if desired and cut at appropriate positions to form aerosol generating articles of a desired size.

(52) Although exemplary embodiments have been described in the preceding paragraphs, it should be understood that various modifications may be made to those embodiments without departing from the scope of the appended claims. Thus, the breadth and scope of the claims should not be limited to the above-described exemplary embodiments.

(53) Any combination of the above-described features in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

(54) Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.