Method of manufacturing an aerosol generator

Abstract

A method of manufacturing an aerosol generator (100) for use as part of a non-combustible aerosol provision system, the method comprising the steps of: (I) providing a carbon precursor (101); (II) irradiating a portion (103) of an outer surface of the carbon precursor (101) with a laser beam, thereby to form an allotrope of carbon (104). In step (II) the laser beam delivers a fluence to the irradiated portion (103) of the outer surface of from about 0.10 J / mm2 to about 0.80 J / mm2.

Description

P20025562METHOD OF MANUFACTURING AN AEROSOU GENERATORFIELD

[0001] The present disclosure relates to a method of manufacturing an aerosol generator, an aerosol generator, and a non-combustible aerosol provision system comprising the aerosol generator.BACKGROUND

[0002] Non-combustible aerosol provision systems that generate an aerosol for inhalation by a user are known in the art. Such systems typically comprise an aerosol generator which is capable of converting an aerosol-generating material into an aerosol. In some instances, the aerosol generated is a condensation aerosol whereby an aerosol-generating material is first vaporised and then allowed to condense into an aerosol. In other instances, the aerosol generated is an aerosol which results from the atomisation of the aerosol-generating material. Such atomisation may be induced mechanically, e.g. by subjecting the aerosol-generating material to vibrations so as to form small particles of material that are entrained in airflow. Alternatively, such atomisation may be induced electrostatically, or in other ways, such as by using pressure.[0003| Since such aerosol provision systems are intended to generate an aerosol which is to be inhaled by a user, consideration should be given to the characteristics of the aerosol produced. These characteristics can include the size of the particles of the aerosol, the total amount of the aerosol produced, etc.

[0004] Where the aerosol provision system is used to simulate a smoking experience, e.g. as an e- cigarette or similar product, control of these various characteristics is especially important since the user may expect a specific sensorial experience to result from the use of the system.

[0005] It would be desirable to provide non-combustible aerosol provision systems which have improved control of these characteristics.SUMMARY

[0006] According to a first aspect of the present disclosure, there is provided a method of manufacturing an aerosol generator for use as part of a non-combustible aerosol provision system, the method comprising the steps of:(I) providing a carbon precursor;P20025562(II) irradiating a portion of an outer surface of the carbon precursor with a laser beam, thereby to form an allotrope of carbon, wherein in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2.

[0007] In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2.

[0008] In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0.25 J / mm2to about 0.35 J / mm2.

[0009] In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0.30 J / mm2to about 0.35 J / mm2.[00101 In some examples, in step (II) the scanning speed of the laser beam is from about 100 mm / s to about 450 mm / s, such as from about 150 mm / s to about 450 mm / s.

[0011] In some examples, in step (II) the laser beam has a power of from about 1 W to about 30 W, optionally from about 3 W to about 21 W.[0012| In some examples, in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C, optionally from about 1800°C to about 2200°C.

[0013] In some examples, in step (II) the laser beam has a wavelength of from 8 pm to 16 pm, optionally from about 9 pm to about 14 pm, optionally from about 10 pm to about 12 pm, optionally wherein in step (II) the laser beam is generated by a carbon dioxide laser.|0014] In some examples, the method comprises the step of:(III) irradiating a portion of an outer surface of the carbon precursor with a laser beam, thereby to form a through-hole in the carbon precursor, optionally wherein an opening of the through-hole is adjacent to the allotrope of carbon.| 0015] In some examples, an opening of the through-hole is partially or completely covered by the allotrope of carbon, optionally wherein the allotrope of carbon at least partially extends into the through-hole.P20025562

[0016] In some examples, the through-hole has a diameter of from about 5 pm to about 200 pm, optionally from about 10 pm to about 100 pm.

[0017] In some examples, the outer surface of the carbon precursor comprises a first surface and a second surface which is opposite from the first surface, wherein the portion of the outer surface is the first surface (or a portion thereof).

[0018] In some examples, the carbon precursor is substantially planar.

[0019] In some examples, the carbon precursor has a thickness of from about 50 pm to about 300 pm, optionally from about 90 pm to about 200 pm, optionally from about 100 pm to about 150 pm, optionally from about 120 pm to about 130 pm.

[0020] In some examples, the allotrope of carbon has a length of from about 2 mm to about 3 mm, a width of from about 1.5 mm to about 2.5 mm.

[0021] In some examples, the allotrope of carbon has an electrical resistance of from about 10 ohms to about 60 ohms, such as from about 40 ohms to about 60 ohms.

[0022] In some examples, the carbon precursor is made of polyimide.[0023| In some examples, the allotrope of carbon comprises disordered graphite and / or amorphous carbon and / or nanocry stalline graphite.[0024| In some examples, a Raman spectrum of the allotrope of carbon comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1500 cm'1to about 1650 cm1, and a D band peak is within a Raman shift range of from about 1250 cm'1to about 1400 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.2 to about 2, optionally from about 0.2 to about 1.6, optionally from about 0.4 to about 0.8, optionally from about 0.4 to about 0.6.|0025] In some examples, in step (II) the laser beam irradiates the portion of the outer surface along one or more scanning lines, optionally wherein adjacent scanning lines are contiguous with each other or overlap each other.

[0026] In some examples, the scanning lines form a scanning pattern which superposes (or overlays) the portion of the outer surface.|0027] In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 50% of the peak intensity of the laser beam.P20025562

[0028] According to a second aspect of the present disclosure, there is provided an aerosol generator for use as part of a non-combustible aerosol provision system, the aerosol generator comprising an allotrope of carbon, wherein aerosol generator is obtained and / or obtainable by the method of the first aspect of the present disclosure.

[0029] According to a third aspect of the present disclosure, there is provided an article for use as part of a non-combustible aerosol provision system comprising: the aerosol generator of the second aspect of the present disclosure; and a reservoir for aerosol-generating material.[0030| According to a fourth aspect of the present disclosure, there is provided a non-combustible aerosol provision system comprising: the article of the third aspect of the present disclosure; and a power source and / or a controller.BRIEF DESCRIPTION OF THE DRAWINGS10031] The present disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:|0032] FIG. 1 is a schematic drawing (not to scale or proportion) of a non-combustible aerosol provision system according to the present disclosure;|0033] FIG. 2 is a schematic drawing of an aerosol generator according to the present disclosure, in plan view, facing the allotrope of carbon;|0034] FIG. 3 is a schematic drawing of the aerosol generator of Fig. 2, in side view;|0035] FIG. 4 is table showing various characteristics of aerosol generators prepared according to the method of the present disclosure;|0036] FIG. 5A shows four scanning electron micrograph images of aerosol generators prepared according to the method of the present disclosure;|0037] FIG. 5B shows four scanning electron micrograph images of aerosol generators prepared according to the method of the present disclosure;P20025562

[0038] FIG. 5C shows four scanning electron micrograph images of aerosol generators prepared according to the method of the present disclosure;

[0039] FIG. 6 shows a plot of temperature (y-axis) against fluence, in respect of allotrope of carbon samples;

[0040] FIG. 7 shows a Raman spectra of an allotrope of carbon sample, in which the x-axis corresponds to Raman shift (cm1) and the y-axis corresponds to intensity (counts), with a D band peak, a G band peak, and a 2D band peak;

[0041] FIG. 8 shows a scanning electronic micrograph image of an aerosol generator prepared according to the method of the present disclosure; and

[0042] FIG. 9 shows Raman spectra of the allotrope of carbon of the aerosol generator of Fig. 7, including a first spectrum taken at a first point of the allotrope of carbon and a second spectrum taken at a second point of the allotrope of carbon.

[0043] While the disclosure is susceptible to various modifications and alternative forms, specific approaches are shown by way of example in the drawings and are herein described in detail. It should be understood however that the drawings and detailed description are not intended to limit the disclosure to the particular form disclosed but rather the disclosure is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the claimed invention.

[0044] It will be recognised that the features of the disclosure can conveniently and interchangeably be used in any suitable combination.DETAILED DESCRIPTION|0045] Aspects and features of certain examples are discussed / described herein. Some aspects and features of certain examples may be implemented conventionally and these are not discussed / described in detail in the interests of brevity. It will thus be appreciated that aspects and features of aerosol generators, articles, and non-combustible aerosol provision systems discussed herein which are not described in detail may be implemented in accordance with any conventional techniques for implementing such aspects and features.

[0046] As described above, the present disclosure relates, but is not limited, to non-combustible aerosol provision systems, articles, and aerosol generators that can generate an aerosol from an aerosol-generating material.P20025562

[0047] According to the present disclosure, a “non-combustible” aerosol provision system is one where a constituent aerosol-generating material of the aerosol provision system (or component thereof) is not combusted or burned in order to facilitate delivery of at least one substance to a user.

[0048] In some examples, the non-combustible aerosol provision system is a powered noncombustible aerosol provision system.

[0049] In some examples, the non-combustible aerosol provision system is an electronic cigarette, also known as a vaping device or electronic nicotine delivery system (END), although it is noted that the presence of nicotine in the aerosol-generating material is not a requirement.

[0050] In some examples, the non-combustible aerosol provision system is an aerosol-generating material heating system, also known as a heat-not-bum system. An example of such a system is a tobacco heating system.

[0051] In some examples, the non-combustible aerosol provision system is a hybrid system to generate aerosol using a combination of aerosol-generating materials, one or a plurality of which may be heated. Each of the aerosol-generating materials may be, for example, in the form of a solid, liquid or gel and may or may not contain nicotine. In some examples, the hybrid system comprises a liquid or gel aerosol-generating material and a solid aerosol-generating material. The solid aerosolgenerating material may comprise, for example, tobacco or a non-tobacco product.[0052| Typically, the non-combustible aerosol provision system may comprise a non-combustible aerosol provision device and a consumable for use with the non-combustible aerosol provision device.[0053| In some examples, the disclosure relates to consumables comprising aerosol-generating material and configured to be used with non-combustible aerosol provision devices. These consumables are sometimes referred to as articles throughout the disclosure.[0054| In some examples, the non-combustible aerosol provision system, such as a non-combustible aerosol provision device thereof, may comprise a power source and / or a controller. The power source may be for supplying electrical power to the article (e.g. to the aerosol generator). The controller may be for controlling the article (e.g. for controlling the supply of power to the article, e.g. to the aerosol generator). The power source may, for example, be an electric power source or an exothermic power source. In some examples, the exothermic power source comprises a carbon substrate which may be energised so as to distribute power in the form of heat to an aerosol -generating material or to a heat transfer material in proximity to the exothermic power source.P20025562

[0055] In some examples, the non-combustible aerosol provision system may comprise an area for receiving the consumable, an aerosol generator, an aerosol generation area, a housing, a mouthpiece, a filter and / or an aerosol-modifying agent.

[0056] In some examples, the consumable for use with the non-combustible aerosol provision device may comprise aerosol-generating material, an aerosol-generating material storage area (which may be referred to herein as a reservoir for aerosol-generating material), an aerosol-generating material transfer component (also referred to herein as an aerosol-generating material transfer component or an aerosol-generating material transfer component), an aerosol generator (also referred to herein as an aerosol generating component), an aerosol generation area (also referred to herein as an aerosol generation chamber), a housing, a wrapper, a filter, a mouthpiece, and / or an aerosol-modifying agent.

[0057] Throughout the following description the terms “e-cigarette” and “electronic cigarette” may sometimes be used. However, it will be appreciated these terms may be used interchangeably with non-combustible aerosol (vapour) provision system as explained above.[0058| The systems described herein typically generate an inhalable aerosol by vaporisation of an aerosol-generating material.[0059| In some examples, the substance to be delivered may be an aerosol-generating material. The aerosol-generating material may comprise one or more active constituents, one or more flavours, one or more aerosol-former materials, and / or one or more other functional materials.

[0060] The active substance as used herein may be a physiologically active material, which is a material intended to achieve or enhance a physiological response. The active substance may for example be selected from nutraceuticals, nootropics, psychoactives. The active substance may be naturally occurring or synthetically obtained. The active substance may comprise for example nicotine, caffeine, taurine, theine, vitamins such as B6 or B12 or C, melatonin, cannabinoids, or constituents, derivatives, or combinations thereof. The active substance may comprise one or more constituents, derivatives or extracts of tobacco, cannabis or another botanical.

[0061] In some examples, the active substance comprises nicotine. In some examples, the active substance comprises caffeine, melatonin or vitamin B12. As noted herein, the active substance may comprise one or more constituents, derivatives or extracts of cannabis, such as one or more cannabinoids or terpenes.

[0062] As noted herein, the active substance may comprise or be derived from one or more botanicals or constituents, derivatives or extracts thereof. As used herein, the term "botanical" includes any material derived from plants including, but not limited to, extracts, leaves, bark, fibres,P20025562 stems, roots, seeds, flowers, fruits, pollen, husk, shells or the like. Alternatively, the material may comprise an active compound naturally existing in a botanical, obtained synthetically. The material may be in the form of liquid, gas, solid, powder, dust, crushed particles, granules, pellets, shreds, strips, sheets, or the like. Example botanicals are tobacco, eucalyptus, star anise, hemp, cocoa, cannabis, fennel, lemongrass, peppermint, spearmint, rooibos, chamomile, flax, ginger, ginkgo biloba, hazel, hibiscus, laurel, licorice (liquorice), matcha, mate, orange skin, papaya, rose, sage, tea such as green tea or black tea, thyme, clove, cinnamon, coffee, aniseed (anise), basil, bay leaves, cardamom, coriander, cumin, nutmeg, oregano, paprika, rosemary, saffron, lavender, lemon peel, mint, juniper, elderflower, vanilla, wintergreen, beefsteak plant, curcuma, turmeric, sandalwood, cilantro, bergamot, orange blossom, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, geranium, mulberry, ginseng, theanine, theacrine, maca, ashwagandha, damiana, guarana, chlorophyll, baobab or any combination thereof. The mint may be chosen from the following mint varieties: Mentha Arventis, Mentha c.v., Mentha niliaca, Mentha piperita, Mentha piperita citrata c.v., Mentha piperita c.v, Mentha spicata crispa, Mentha cardifolia, Memtha longifolia, Mentha suaveolens variegata, Mentha pulegium, Mentha spicata c.v. and Mentha suaveolens

[0063] In some examples, the active substance comprises or is derived from one or more botanicals or constituents, derivatives or extracts thereof and the botanical is tobacco.

[0064] In some examples, the active substance comprises or derived from one or more botanicals or constituents, derivatives or extracts thereof and the botanical is selected from eucalyptus, star anise, cocoa and hemp.[0065| In some examples, the active substance comprises or derived from one or more botanicals or constituents, derivatives or extracts thereof and the botanical is selected from rooibos and fennel.[0066| In some examples, the substance to be delivered comprises a flavour.

[0067] As used herein, the terms "flavour" and "flavourant" refer to materials which, where local regulations permit, may be used to create a desired taste, aroma or other somatosensorial sensation in a product for adult consumers. They may include naturally occurring flavour materials, botanicals, extracts of botanicals, synthetically obtained materials, or combinations thereof (e.g., tobacco, cannabis, licorice (liquorice), hydrangea, eugenol, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, maple, matcha, menthol, Japanese mint, aniseed (anise), cinnamon, turmeric, Indian spices, Asian spices, herb, wintergreen, cherry, berry, red berry, cranberry, peach, apple, orange, mango, clementine, lemon, lime, tropical fruit, papaya, rhubarb, grape, durian, dragon fruit, cucumber, blueberry, mulberry, citrus fruits, Drambuie, bourbon, scotch, whiskey, gin, tequila, rum,P20025562 spearmint, peppermint, lavender, aloe vera, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, khat, naswar, betel, shisha, pine, honey essence, rose oil, vanilla, lemon oil, orange oil, orange blossom, cherry blossom, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, wasabi, piment, ginger, coriander, coffee, hemp, a mint oil from any species of the genus Mentha, eucalyptus, star anise, cocoa, lemongrass, rooibos, flax, ginkgo biloba, hazel, hibiscus, laurel, mate, orange skin, rose, tea such as green tea or black tea, thyme, juniper, elderflower, basil, bay leaves, cumin, oregano, paprika, rosemary, saffron, lemon peel, mint, beefsteak plant, curcuma, cilantro, myrtle, cassis, valerian, pimento, mace, damien, maijoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, limonene, thymol, camphene), flavour enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and / or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They may be imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, liquid such as an oil, solid such as a powder, or gas.|0068] In some examples, the flavour comprises menthol, spearmint and / or peppermint. In some examples, the flavour comprises flavour components of cucumber, blueberry, citrus fruits and / or redberry. In some examples, the flavour comprises eugenol. In some examples, the flavour comprises flavour components extracted from tobacco. In some examples, the flavour comprises flavour components extracted from cannabis.[0069| In some examples, the flavour may comprise a sensate, which is intended to achieve a somatosensorial sensation which are usually chemically induced and perceived by the stimulation of the fifth cranial nerve (trigeminal nerve), in addition to or in place of aroma or taste nerves, and these may include agents providing heating, cooling, tingling, numbing effect. A suitable heat effect agent may be, but is not limited to, vanillyl ethyl ether and a suitable cooling agent may be, but not limited to eucolyptol, WS-3.

[0070] Aerosol-generating material is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way. Aerosol-generating material may, for example, be in the form of a liquid or gel which may or may not contain an active substance and / or flavourants.10071] The aerosol-generating material may comprise one or more active substances and / or flavours, one or more aerosol-former materials, and optionally one or more other functional material.|0072] The aerosol-former material may comprise one or more constituents capable of forming an aerosol. In some examples, the aerosol-former material may comprise one or more of glycerol,P20025562 propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl suberate, triethyl citrate, triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate.10073] The one or more other functional materials may comprise one or more of pH regulators, colouring agents, preservatives, binders, fdlers, stabilizers, and / or antioxidants.10074] As used herein, the term “consumable” may refer to an article comprising or consisting of aerosol-generating material, part or all of which is intended to be consumed during use by a user. A consumable may comprise one or more other components, such as an aerosol-generating material storage area, an aerosol-generating material transfer component, an aerosol generation area, a housing, a wrapper, a mouthpiece, a fdter and / or an aerosol-modifying agent. A consumable may also comprise an aerosol generator, such as a heater, that emits heat to cause the aerosol-generating material to generate aerosol in use. The heater may, for example, comprise combustible material, a material heatable by electrical conduction, or a susceptor. The consumable may be suitable for holding (or containing) the aerosol-generating material. In this way, the consumable may, but need not necessarily, hold (or contain) the aerosol-generating material.

[0075] As used herein, the term “susceptor” refers to a material that is heatable by penetration with a varying magnetic field, such as an alternating magnetic field. The susceptor may be an electrically- conductive material, so that penetration thereof with a varying magnetic field causes induction heating of the heating material. The heating material may be magnetic material, so that penetration thereof with a varying magnetic field causes magnetic hysteresis heating of the heating material. The susceptor may be both electrically-conductive and magnetic, so that the susceptor is heatable by both heating mechanisms. The device that is configured to generate the varying magnetic field is referred to as a magnetic field generator, herein.

[0076] As used herein, the term “component” is used to refer to a part, section, unit, module, assembly or similar of an electronic cigarette or similar device that incorporates several smaller parts or elements, possibly within an exterior housing or wall. An electronic cigarette may be formed or built from one or more such components, and the components may be removably or separably connectable to one another, or may be permanently joined together during manufacture to define the whole electronic cigarette. The present disclosure is applicable to (but not limited to) systems comprising two components separably connectable to one another and configured, for example, as a consumable / article component capable of holding an aerosol generating material (also referred to herein as a cartridge or cartomiser), and a device / control unit having a battery for providing electrical power to operate an element for generating vapour from the aerosol generating material.P20025562

[0077] An aerosol-modifying agent is a substance, typically located downstream of the aerosol generation area, that is configured to modify the aerosol generated, for example by changing the taste, flavour, acidity or another characteristic of the aerosol. The aerosol-modifying agent may be provided in an aerosol-modifying agent release component that is operable to selectively release the aerosol-modifying agent.10078] The aerosol-modifying agent may, for example, be an additive or a sorbent. The aerosolmodifying agent may, for example, comprise one or more of a flavourant, a colourant, water, and a carbon adsorbent. The aerosol-modifying agent may, for example, be a solid, a liquid, or a gel. The aerosol-modifying agent may be in powder, thread or granule form. The aerosol -modifying agent may be free from filtration material.

[0079] An aerosol generator (or aerosol generating component) is an apparatus configured to cause aerosol to be generated from the aerosol-generating material. In some examples, the aerosol generator is a heater configured to subject the aerosol-generating material to heat energy, so as to release one or more volatiles from the aerosol-generating material to form an aerosol. In some examples, the aerosol generator is configured to cause an aerosol to be generated from the aerosol-generating material without heating. For example, the aerosol generator may be configured to subject the aerosolgenerating material to one or more of vibration, increased pressure, or electrostatic energy.|0080] Fig. 1 is a highly schematic diagram (not to scale or proportion) of an example noncombustible aerosol provision system such as an e-cigarette 10. The e-cigarette 10 has a generally cylindrical shape, extending along a longitudinal axis indicated by a dashed line, and comprises two main components, namely a control or power component or section 20 (which may be referred to herein as a “device”) and a cartridge assembly or section 30 (which may be referred to herein as an “article”, “consumable”, “cartomizer”, or “cartridge”) that operates as a vapour generating component.[00811 The article 30 includes a storage compartment (also referred to herein as a “reservoir”) 3 containing an aerosol-generating material comprising (for example) a liquid formulation from which an aerosol is to be generated. The liquid formulation may or may not contain nicotine. As an example, the aerosol-generating material may comprise around 1 to 3% nicotine and 50% glycerol, with the remainder comprising roughly propylene glycol, and possibly also comprising other components, such as water or flavourings. The storage compartment 3 has the form of a storage tank, i.e. a container or receptacle in which aerosol-generating material can be stored such that the aerosol-generating material is free to move and flow (if liquid) within the confines of the container or receptacle.Alternatively, the storage compartment 3 may contain a quantity of absorbent material such as cotton wadding or glass fibre which holds the aerosol-generating material within a porous structure. TheP20025562 storage compartment 3 may be sealed after filling during manufacture so as to be disposable after the aerosol-generating material is consumed, or may have an inlet port or other opening through which new aerosol-generating material can be added. The article 30 also comprises an electrical aerosol generator 4 located externally of the storage compartment 3 for generating the aerosol by vaporisation of the aerosol-generating material. In many examples, the aerosol generator is a heating element (a heater) which is heated by the passage of electrical current (via resistive or inductive heating) to raise the temperature of the aerosol-generating material until it evaporates. An aerosol generating material transfer component (not shown in Fig. 1), e.g. a liquid conduit arrangement such as a wick or other porous element, may be provided to deliver aerosol-generating material from the storage compartment 3 to the aerosol generator 4. The aerosol generating material transfer component may have one or more parts located inside the storage compartment 3 so as to be able to absorb aerosol-generating material and transfer it by wicking or capillary action to other parts of the aerosol generating material transfer component that are in contact with the aerosol generator 4. This aerosol-generating material is thereby vaporised, and is to be replaced by new aerosol-generating material transferred to the aerosol generator 4 by the aerosol generating material transfer component.[0082| A heater and wick combination, or other arrangement of parts that perform the same functions, is sometimes referred to as an atomiser or atomiser assembly. Various designs are possible, in which the parts may be differently arranged compared to the highly schematic representation of Fig. 1. For example, the wick may be an entirely separate element from the aerosol generator.[0083| In some examples, the aerosol generating material transfer component 4 (e.g. a liquid conduit) for delivering liquid for vapour generation may be formed at least in part from one or more slots, tubes or channels between the storage compartment and the aerosol generator which are narrow enough to support capillary action to draw source liquid out of the storage compartment and deliver it for vaporisation. In general, an atomiser can be considered to be an aerosol generator 4 able to generate vapour from aerosol-generating material delivered to it, and an aerosol generating material transfer component (e.g. a liquid conduit) able to deliver or transport liquid from the storage compartment 3 or similar liquid store to the aerosol generator by a capillary force.|0084] In some examples, the aerosol generator is at least partially located within an aerosol generating chamber that forms part of an airflow channel through the electronic cigarette / system. Vapour produced by the aerosol generator is driven off into this chamber, and as air passes through the chamber, flowing over and around the aerosol generator, it collects the produced vapour whereby it condenses to form the demanded aerosol.P20025562

[0085] Returning to Fig. 1, the cartridge assembly 30 also includes a mouthpiece 35 having an opening or air outlet through which a user may inhale the aerosol generated by the aerosol generator 4, and delivered through the airflow channel.

[0086] The power component (or device) 20 includes a cell 5 (e.g. a “battery”), which may be rechargeable, to provide power for electrical components of the e-cigarette 10, in particular the aerosol generator 4. Additionally, there is a printed circuit board 28 and / or other electronics or circuitry for generally controlling the e-cigarette 10. The control electronics / circuitry connect the aerosol generating element 4 to the battery 5 when vapour is demanded, for example in response to a signal from an air pressure sensor or air flow sensor (not shown) that detects an inhalation on the system 10 during which air enters through one or more air inlets in the wall of the power component 20 to flow along the airflow channel. When the aerosol generator 4 receives power from the cell 5, the aerosol generator 4 vaporises aerosol-generating material delivered from the storage compartment 3 to generate the aerosol, and the aerosol is then inhaled by a user through the opening in the mouthpiece 35. The aerosol is carried to the mouthpiece 35 along the airflow channel (not shown) that connects the air inlet to the air outlet when a user inhales on the mouthpiece 35. An airflow path through the electronic cigarette is hence defined, between the air inlet(s) (which may or may not be provided in the power component 20) to the atomiser and on to the air outlet at the mouthpiece. In use, the air flow direction along this airflow path is from the air inlet to the air outlet, so that the atomiser can be described as arranged downstream of the air inlet and upstream of the air outlet.[008*7] In this particular example, the power component 20 and the cartridge assembly 30 are separate parts detachable from one another by separation in a direction parallel to the longitudinal axis. The components 20, 30 are joined together when the device 10 is in use by cooperating engagement elements 21, 31 (for example, a screw, magnetic or bayonet fitting) which provide mechanical and electrical connectivity between the power section 20 and the cartridge assembly 30. This is merely an example arrangement, however, and the various components may be differently distributed between the power section 20 and the cartridge assembly 30, and other components and elements may be included. The two sections 20, 30 may connect together end-to-end in a longitudinal configuration as in Fig. 1, or in a different configuration such as a parallel, side-by-side arrangement. The non-combustible aerosol provision system 10 may or may not be generally cylindrical and / or have a generally longitudinal shape. Either or both sections may be intended to be disposed of and replaced when exhausted (the reservoir is empty or the battery is flat, for example), or be intended for multiple uses enabled by actions such as refilling the reservoir, recharging the battery, or replacing the atomiser. Alternatively, the e-cigarette 10 may be a unitary device (disposable or refillable / rechargeable) that cannot be separated into two or more parts, in which case all componentsP20025562 are comprised within a single body or housing. Examples of the present disclosure are applicable to any of these configurations and other configurations of which the skilled person will be aware.

[0088] As mentioned herein, a type of aerosol generator, such as a heating element, that may be utilised in an atomising portion of an electronic cigarette 10 (a part configured to generate vapour from a source liquid) combines the functions of heating and liquid delivery, by being both electrically conductive (resistive) and porous. Note here that reference to being electrically conductive (resistive) refers to components which have the capacity to generate heat in response to the flow of electrical current therein. Such flow could be imparted by via so-called resistive heating or induction heating. The aerosol generator may be of a sheet-like form, i.e. a planar shape with a thickness many times smaller than its length or breadth. It is possible for the planar aerosol generator to define a curved plane and in these instances reference to the planar aerosol generator forming a plane means an imaginary flat plane forming a plane of best fit through the component.

[0089] The aerosol generator (e.g. the allotrope of carbon thereof) may comprise appropriately sized voids and / or interstices to provide a capillary force for wicking aerosol-generating material (e.g. liquid). Thus, the aerosol generator (e.g. the allotrope of carbon thereof) may also be considered to be porous, so as to provide for the uptake and distribution of aerosol-generating material (e.g. liquid). Moreover, the presence of voids and / or interstices may mean air can permeate through said aerosol generator. Also, at least part of the aerosol generator is electrically conductive and therefore suitable for resistive heating, whereby electrical current flowing through a material with electrical resistance generates heat.

[0090] An aerosol generator (e.g. which is planar and / or sheet-like) may be arranged within a noncombustible aerosol provision system (e.g. an electronic cigarette), such that the aerosol generator lies within the aerosol generating chamber forming part of an airflow channel. The aerosol generator may be oriented within the chamber such that air flow though the chamber may flow in a surface direction, i.e. substantially parallel to the plane of the aerosol generator. An example of such a configuration can be found in W02010 / 045670 and W02010 / 045671, the contents of which are incorporated herein in their entirety by reference. Air can thence flow over the aerosol generator (e.g. the allotrope of carbon thereof), and gather vapour. Aerosol generation is thereby made effective. In alternative examples, the aerosol generator may be oriented within the chamber such that air flow though the chamber may flow in a direction which is substantially transverse to the surface direction, i.e. substantially orthogonally to the plane of the aerosol generator. An example of such a configuration can be found in WO2018 / 211252, the contents of which are incorporated herein in its entirety by reference.P20025562

[0091] The aerosol generator (e.g. the allotrope of carbon thereof) may have a high degree of porosity. A high degree of porosity may ensure that the heat produced by the aerosol generator is predominately used for evaporating the liquid and high efficiency can be obtained. A porosity of greater than 50% may be envisaged. In one example, the porosity of the aerosol generator is 50% or greater, 60% or greater, 70% or greater.10092] The aerosol generator may form a generally flat structure, comprising first and second surfaces. The generally flat structure may take the form of any two dimensional shape, for example, circular, semi-circular, triangular, square, rectangular and / or polygonal. The aerosol generator may have a uniform thickness.

[0093] Where the aerosol generator (e.g. the allotrope of carbon thereof) is formed from an electrically resistive material, electrical current is permitted to flow through the aerosol generator (e.g. the allotrope of carbon thereof) so as to generate heat (so called Joule heating). In this regard, the electrical resistance of the aerosol generator (e.g. the allotrope of carbon thereof) can be selected appropriately. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 1 ohms to 1000 ohms. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 1 ohms to 200 ohms. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 10 ohms to 150 ohms. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 20 ohms to 100 ohms. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 30 ohms to 70 ohms. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 40 ohms to 60 ohms. For example, the aerosol generator (e.g. the allotrope of carbon thereof) may have an electrical resistance of from 45 ohms to 55 ohms. In this regard, a relatively lower resistance will facilitate higher power draw from the power source, which can be advantageous in producing a high rate of aerosolisation. On the other hand, the resistance should not be so low as to prejudice the integrity of the aerosol generator (e.g. the allotrope of carbon thereof). For example, the resistance may not be lower than 0.5 ohms.Method|0094] According to a first aspect of the present disclosure, there is provided a method of manufacturing an aerosol generator 101 for use as part of a non-combustible aerosol provision system, the method comprising the steps of:(I) providing a carbon precursor 101;P20025562(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2.

[0095] The aerosol generator 100 thus provided is schematically illustrated in Figs. 2 and 3.

[0096] The present inventors have developed a method of manufacturing an aerosol generator for use as part of a non-combustible aerosol provision, which method involves irradiating a carbon precursor with a laser beam thereby to form an allotrope of carbon.

[0097] The present inventors have found that characteristics of the allotrope of carbon can be influenced by varying parameters of the laser beam by which the allotrope of carbon is irradiated. For example, the present inventors have found that the porosity, electrical conductivity, thermal conductivity, and mechanical integrity (or robustness) of the allotrope of carbon can be affected by the varying the parameters. The present inventors have tuned the parameters to provide for an aerosol generator which is porous, electrically conductive, and thermally conductive, and has requisite mechanical integrity. In this way, an aerosol generator manufactured according to the present method can exhibit excellent performance, for example in terms of liquid transport and distribution, aerosol generation, mechanical integrity, and heat-up time and cool-down time.[0098| The present inventors have found that the fluence of the laser beam in step (II) has an appreciable impact on the characteristics of the allotrope of carbon, and that using a fluence of from about 0.10 J / mm2to about 0.80 J / mm2(from example from about 0.14 J / mm2to about 0.54 J / mm2) provides for an aerosol generator which exhibits desirable performance, for example in terms of liquid transport and distribution, aerosol generation, mechanical integrity, and heat-up time and cool-down time. In this regard, the present inventors have found that using a lower fluence can provide for an allotrope of carbon having low or no electrically conductivity, and that using a greater fluence can damage the allotrope of carbon. Damage to the allotrope of carbon can result in parts of the allotrope of carbon breaking away during use, reduction in performance of the allotrope of carbon, and / or total failure of the allotrope of carbon.Step (I) - providing the carbon precursor

[0099] Step (I) of the method comprises providing a carbon precursor.10100] The term “carbon precursor” refers to a material that comprises carbon.

[0101] It is to be understood that various carbon precursors can be used.P20025562

[0102] In some examples, the carbon precursor is selected from the group consisting of plastic, glass, paper, and ceramic.

[0103] In some examples, the plastic is a thermoplastic.[0104| In some examples, the plastic is selected from the group comprising polyimides, polyetherketones, polysulfones, or a combination thereof.

[0105] In some examples, the polyimides are selected from the group comprising polyetherimides, polyamideimides, or a combination thereof. In some examples, the carbon precursor is a polyimide. In some examples, the polyimide is poly(4,4'-oxydiphenylene-pyromellitimide). Poly(4,4'- oxydiphenylene-pyromellitimide) is commercially available from DuPont under the trade name Kapton® HN (and other Kapton® products).

[0106] In some examples, the polyetherketones are selected from the group comprising polyetheretherketones, poly etherketoneketone, polyether ether ketone ketone, polyetherketoneetherketoneketone, or a combination thereof.|0107] In some examples, the polysulfones are selected from the group comprising poly(arylene sulfone), poly(bisphenol-A sulfone), polyether sulfone, polyphenylene sulfone, poly(oxy-l,4- phenylenesulfonyl-l,4-phenylene), or a combination thereof.|0108] In some examples, the glass is selected from the group comprising silicate glass, non-silicate glass, or a combination thereof. In some examples, the silicate glass is selected from the group comprising borosilicate glass, quartz glass (fused quartz), or a combination thereof.

[0109] In some examples, the carbon precursor 101 comprises a polyimide or a polyetheretherketone. In some examples, the carbon precursor 101 is a polyimide or a poly etheretherketone.

[0110] In some examples, the carbon precursor is flexible.|0111] In some examples, the carbon precursor 101 is non-porous. For example, when the carbon precursor 101 is a polyimide, the polyimide may be non-porous. It is to be understood that “non- porous” may encompass embodiments in which at least one through-hole (102, discussed below) is formed through the carbon precursor 101. In this way, the term “non-porous” can be considered as referring to the skeletal portion (or matrix) of the carbon precursor 101. Such through-holes 102 can be effectively ignored in relation to the assessment of whether the carbon precursor 101 is non-porous (where these do not form the matrix of the carbon precursor 101).P20025562

[0112] In some examples, the carbon precursor 101 has a porous structure formed from pillars and interstitial pores (which may be referred to herein as “voids” and / or “interstices”). The allotrope of carbon 104 may be formed on the pillars as a coating. For example, the interstitial pores may have an average pore size of from 0.5 to 40 pm (although this may vary). The average pore size may be the mean pore size or the median pore size. The average pore size may be determined methods including (but not limited to) mercury intrusion porosimetry or gas adsorption. Those skilled in the art are familiar with such methods.Form of the carbon precursor

[0113] The carbon precursor 101 may be provided in various forms.

[0114] In some examples, the carbon precursor 101 has an outer surface. In some examples, the outer surface comprises a first surface. The first surface may be substantially planar. In some examples, the outer surface comprises a second surface. The second surface may be opposite from the first surface (herein “an opposing second surface”). The second surface may be substantially planar. In some examples, the carbon precursor 101 is substantially planar.

[0115] In some examples, the outer surface comprises a substantially planar first surface and a substantially planar second surface that is opposite from the first surface.

[0116] In some examples, the carbon precursor 101 has a thickness of from about 40 pm to about 500 pm.

[0117] Herein, the thickness of the carbon precursor 101 is measured orthogonally to the plane or lateral extent of the carbon precursor 101, e.g. from the first surface to the second surface.

[0118] In some examples, the carbon precursor 101 has a thickness of from about 40 pm to about 300 pm. In some examples, the carbon precursor 101 has athickness of from about 80 pm to about300 pm. In some examples, the carbon precursor 101 has athickness of from about 90 pm to about200 pm. In some examples, the carbon precursor 101 has a thickness of from about 100 pm to about150 pm. In some examples, the carbon precursor 101 has a thickness of from about 120 pm to about130 pm.

[0119] Any of the thickness features may be combined with any other features of the carbon precursor 101. For example, in some examples, the carbon precursor 101 comprises an outer surface and is substantially planar, the outer surface comprising a substantially planar first surface and an opposing substantially planar second surface, wherein the thickness of the carbon precursor 101 is from about 90 pm to about 200 pm, optionally from about 100 pm to about 150 pm, optionally from about 120 pm to about 130 pm, optionally wherein the carbon precursor 101 is a polyimide.P20025562Step (II) - irradiation to form an allotrope of carbon|0120] The method comprises step (II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104. The allotrope of carbon 104 may be porous. The allotrope of carbon 104 may be electrically conductive. The allotrope of carbon 104 may be thermally conductive. With reference to the figures, the irradiated portion 103 is best indicated in Fig. 2. It will be appreciated that the allotrope of carbon 104 forms at the irradiated portion 103, and so the reference numerals for these respective items concern substantially the same location.[0121 | In some examples, the portion 103 of the outer surface is a portion of the first surface. Thus, in some examples, the method comprises step (II) irradiating a portion 103 of the first surface of the carbon precursor with a laser beam, thereby to form an allotrope of carbon 104.[0122| Thus, in some examples, the method comprises the steps of:(I) providing a carbon precursor 101, the carbon precursor 101 comprising an outer surface and being substantially planar, the outer surface comprising a substantially planar first surface and an opposing substantially planar second surface, wherein the thickness of the carbon precursor 101 is from about 90 pm to about 200 pm, optionally from about 100 pm to about 150 pm, optionally from about 120 pm to about 130 pm, optionally wherein the carbon precursor 101 is a polyimide; and(II) irradiating a portion 103 of the first surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the first surface of from about 0.10 J / mm2to about 0.80 J / mm2.Form of the irradiated portion

[0123] The irradiated portion 103 may take various forms.

[0124] In some examples, the irradiated portion 103 takes a rectangular form.|0125] In some examples, the irradiated portion 103 has a length of from about 0.5 mm to about 6 mm. In some examples, the irradiated portion 103 has a length of from about 1 mm to about 4 mm. In some examples, the irradiated portion has a length of from about 2 mm to about 3.2 mm. In some examples, the irradiated portion 103 has a length of from about 2.2 mm to about 3 mm. In some examples, the irradiated portion 103 has a length of from about 2.4 mm to about 2.8 mm. In any of these examples, the irradiated portion 103 may take a rectangular shape.P20025562

[0126] In some examples, the irradiated portion 103 has a width of from about 0.5 mm to about 6 mm. In some examples, the irradiated portion 103 has a width of from about 1 mm to about 4 mm. In some examples, the irradiated portion 103 has a width of from about 1.4 mm to about 2.6 mm. In some examples, the irradiated portion 103 has a width of from about 1.6 mm to about 2.2 mm. In some examples, the irradiated portion 103 has a width of from about 1.7 mm to about 2. 1 mm. In any of these examples, the irradiated portion 103 may take a rectangular shape.

[0127] In some examples, the irradiated 103 portion has a length from about 0.5 mm to about 6 mm and a width of from about 0.5 mm to about 6 mm. In some examples, the irradiated portion 103 has a length from about 1 mm to about 4 mm and a width of from about 0.5 mm to about 5 mm. In some examples, the irradiated portion 103 has a length from about 2 mm to about 3.2 mm and a width of from about 1.4 mm to about 2.6 mm. In some examples, the irradiated portion 103 has a length from about 2.2 mm to about 3 mm and a width of from about 1.6 mm to about 2.2 mm. In some examples, the irradiated portion 103 has a length from about 2.4 mm to about 2.8 mm and a width of from about 1.7 mm to about 2. 1 mm. In any of these examples, the irradiated portion 103 may take a rectangular form.Fluence. Scanning Speed, and Temperature

[0128] In step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2.

[0129] It will be appreciated that laser beams can have varying intensity profdes. For example, Gaussian laser beams have a Gaussian intensity profde, whereas flat top laser beams have a substantially constant intensity profde.

[0130] Herein, “fluence” refers to the amount of energy delivered by the laser beam to the portion 103 of the outer surface per unit area. Those skilled in the art will readily understand how to determine and specify the fluence of the laser beam. Herein, where the laser beam has a Gaussian intensity profde, the fluence of the laser beam is determined using the 1 / e2beam diameter of the laser beam.

[0131] For example, fluence may be represented by the following formula:PowerFluence = — - - - - - -Velocity x beam diameter wherein fluence is the amount of energy delivered by the laser beam per unit surface area, power is the power of the laser beam, velocity is the scanning speed of the laser beam, and beam diameter isP20025562 the beam diameter (e.g. 1 / e2) of the laser beam. As discussed herein, where the laser beam has a Gaussian intensity profde the beam diameter is the 1 / e2beam diameter.

[0132] In some examples, in step (II) the fluence is substantially constant. In some examples, in step (II) the fluence is variable.

[0133] In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.10 J / mm2to about 0.60 J / mm2. In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.14 J / mm2to about 0.54 J / mm2. In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.25 J / mm2to about 0.35 J / mm2. In some examples, in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.30 J / mm2to about 0.35 J / mm2.

[0134] In some examples, in step (II) the laser beam has a scanning speed of from about 1 mm / s to about 450 mm / s. In some examples, in step (II) the laser beam has a scanning speed of from about 50 mm / s to about 450 mm / s. In some examples, in step (II) the laser beam has a scanning speed of from about 100 mm / s to about 450 mm / s. In some examples, in step (II) the laser beam has a scanning speed of from about 150 mm / s to about 450 mm / s. In some examples, in step (II) the laser beam has a scanning speed of from about 200 mm / s to about 450 mm / s.

[0135] In some examples, in step (II) the laser beam irradiates the portion of the outer surface along one or more scanning lines. In some examples, in step (II) the laser beam irradiates the portion of the outer surface along a plurality of scanning lines. The scanning lines may be straight. The scanning lines may be curved. The scanning lines may form a scanning pattern. It will be understood that the scanning pattern superposes the portion of the outer surface. The scanning pattern may comprise a plurality of lines (e.g. straight lines), which may be arranged side-by-side. Adjacent scanning lines may be spaced apart from each other. Adjacent scanning lines may be contiguous with each other. Adjacent scanning lines may overlap each other. The peak intensity of the laser beam is delivered at the centre point (or central axis) of the scanning line. In some examples, in step (II), the centre point (or central axis) of adjacent scanning lines are spaced apart by a distance which is approximately equal to the beam diameter (1 / e2) of the laser beam.

[0136] In some examples, in step (II) adjacent scanning lines are overlapping (to provide a region of overlap), such that the region of overlap is subjected to at least about 13.5% of the peak intensity of the later beam. In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 20% of the peak intensity of the later beam. In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap isP20025562 subjected to at least about 40% of the peak intensity of the later beam. In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 50% of the peak intensity of the later beam. In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 60% of the peak intensity of the later beam. In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 80% of the peak intensity of the later beam. In some examples, in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 90% of the peak intensity of the later beam.[013*7] In some examples, in step (II) the laser beam moves along the one or more scanning lines at the scanning speed. The scanning speed may be constant. This may improve the uniformity of the allotrope of carbon 104 thus formed and improve the consistency in performance thereof. It will be appreciated that the laser beam may power-off between adjacent scanning lines.

[0138] In some examples, in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C. In some examples, in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1350°C to about 3300°C. In some examples, in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1500°C to about 3000°C. In some examples, in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1700°C to about 2600°C. In some examples, in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1800°C to about 2200°C.

[0139] It will be understood that the temperature corresponds to the peak temperature at the portion of the outer surface.

[0149] Any of the features in step (II) relating to fluence, scanning speed, and temperature may be combined.Laser

[0141] In some examples, step (II) of the method is performed using a Keyence ML-Z9610 laser system. It will be appreciated that other laser systems may be used.

[0142] In some examples, in step (II) the laser beam has a Gaussian intensity profde. In some example, in step (II) the laser beam has a substantially constant intensity profile.P20025562Step (II) parameters|0143] Those skilled in the art will appreciate that in step (II) the properties of the laser beam may be varied. For example, those skilled in the art will appreciate that a particular value of fluence can be provided using varying combinations of laser beam parameters. Such laser beam parameters include, for example, wavelength, beam diameter, and power.|0144] The laser beam in step (II) is generated by a laser. In some examples, in step (II) the laser is an infrared laser. In some examples, in step (II) the laser is a carbon dioxide laser.|0145] In some examples, in step (II) the laser beam has a wavelength of from about 8 pm to about 16 pm. In some examples, in step (II) the laser beam has a wavelength of from about 9 pm to about 14 pm. In some examples, in step (II) the laser beam has a wavelength of from about 10 pm to about 12 pm (e.g. about 10.6 pm).|0146] In some examples, in step (II) the laser beam has a beam diameter (1 / e2) of from about 120 pm to 160 pm. In some examples, in step (II) the laser beam has a beam diameter (1 / e2) of from about 130 pm to 150 pm. In some examples, in step (II) the laser beam has a beam diameter (1 / e2) of from about 135 pm to 145 pm (e.g. about 140 pm). The term “beam diameter ( 1 / e2)” will be understood by the skilled person.

[0017] In some examples, in step (II) the laser beam has a power of from 1 W to about 30 W. In some examples, in step (II) the laser beam has a power of from about 3 W to about 25 W. In some examples, in step (II) the laser beam has a power of from about 6 W to about 21 W.

[0148] In some examples, in step (II) the laser beam has: a wavelength of from about 8 pm to about 16 pm; a beam diameter (1 / e2) of from about 120 pm to 160 pm; and / or a power of from about 1 W to about 30 W.[0149| In some examples, in step (II) the laser beam has: a wavelength of from about 9 pm to about 14 pm; a beam diameter (1 / e2) of from about 130 pm to 150 pm; and / or a power of from about 6 W to about 21 W.

[0150] In some examples, in step (II) the laser beam has: a wavelength of from about 10 pm to about 12 pm; a beam diameter (1 / e2) of from about 135 pm to 145 pm; and / or a power of from about 6 W to about 21 W.

[0151] Any of the laser beam parameters may be combined with any other features of the method.P20025562Combinations

[0152] In some examples, the method comprises the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2, optionally from about 0.14 J / mm2to about 0.54 J / mm2, optionally from about 0.25 J / mm2to about 0.35 J / mm2, optionally from about 0.30 J / mm2to about 0.35 J / mm2, optionally wherein in step (II) the laser beam may have: a scanning speed of from about 1 mm / s to about 450 mm / s, optionally from about 50 mm / s to about 450 mm / s, optionally from about 100 mm / s to about 450 mm / s, optionally from about 150 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C.10153] For example, the method may comprise the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2, optionally wherein in step (II) the laser beam has: a scanning speed of from about 1 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C.[01541 For example, the method may comprise the steps of:(I) providing a carbon precursor 101; andP20025562(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally wherein in step (II) the laser beam has: a scanning speed of from about 50 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C .10155] For example, the method may comprise the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally from about 0.25 J / mm2to about 0.35 J / mm2, optionally wherein in step (II) the laser beam has: a scanning speed of from about 100 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C.

[0156] For example, the method may comprise the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of the outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally from about 0.25 J / mm2to about 0.35 J / mm2,P20025562 optionally wherein the laser beam in step (II) has: a scanning speed of from about 150 mm / s to about450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C .

[0157] Any of the above combinations (herein “the above combinations”) may include any other features disclosed herein. For example, in any of the above combinations, the carbon precursor 101 may comprise an outer surface and be substantially planar, the outer surface comprising a substantially planar first surface and an opposing substantially planar second surface, wherein the thickness of the carbon precursor 101 is from about 90 pm to about 200 pm, optionally from about 100 pm to about 150 pm, optionally from about 120 pm to about 130 pm. For example, in any of the above combinations, the carbon precursor 101 may be a polyimide. The portion of the outer surface may be the first surface or a portion thereof.Fluid Feed Holes

[0158] The method may comprise step (III) irradiating a portion 103’ of an outer surface of the carbon precursor 101 with a laser beam, thereby to form a through-hole 102 in the carbon precursor. It will be understood that “a through-hole” means “at least one through-hole”. In some examples, the method comprises step (III) irradiating a portion 103’ of an outer surface of the carbon precursor 101 with a laser beam, thereby to form a plurality of through-holes 102 in the carbon precursor. The or each through-hole 102 may be as defined herein.

[0159] The present inventors have found that the through-hole(s) 102 help to facilitate liquid transport across and / or through the allotrope of carbon 104 in use, and can provide for improved aerosol generation performance.|0160] In some examples, in step (III) the portion 103’ of the outer surface is the first surface. Thus, in some examples, the method comprises step (III) irradiating a portion 103’ of the outer surface of the carbon precursor 101 with a laser beam, thereby to form a through-hole 102 in the carbon precursor 101.|0161] In some examples, an opening of the through-hole 102 is adjacent to the allotrope of carbon 103. Such an arrangement is shown, for example, in Figs. 2 and 3.|0162] In some examples, step (II) occurs before step (III).P20025562

[0163] In preferred examples, step (II) occurs after step (III). Performing step (III) before step (II) facilitates the removal of any debris resulting from step (III), before performing step (II). By contrast, performing step (II) before step (III) may result in damage to the allotrope of carbon 104.

[0164] In some examples, step (II) and step (III) are performed using different laser systems.

[0165] In some examples step (II) and step (III) are performed using a single laser system.

[0166] In some examples, an opening of the through-hole 102 is partially or completely covered by the allotrope of carbon 103. The present inventors have found that such arrangements facilitate improved transport and distribution of aerosol-generating material across and / or through the allotrope of carbon 104.

[0167] In some examples, the allotrope of carbon 103 at least partially extends into the through-hole 102. The present inventors have found that such arrangements facilitate improved transport and distribution of aerosol-generating material across and / or through the allotrope of carbon 104.

[0168] In some examples, the through-hole 102 has a diameter of from about 1 pm to about 300 pm. In some examples, the through-hole 102 has a diameter of from about 5 pm to about 200 pm. In some examples, the through-hole 102 has a diameter of from about 30 pm to about 100 pm. The present inventors have found that such diameters facilitated improved transport of aerosol-generating material to the outer surface of the allotrope of carbon 104. The present inventors have also found that such diameters do not result in significant leakage of aerosol-generating material.

[0019] In some examples, the irradiated portion 103’ in step (III) is within the irradiated portion 101 in step (II). For example, the irradiated portion 103’ in step (III) may be within an outer perimeter of the irradiated portion 101 in step (II), when viewed orthogonally to the plane or lateral extent of the allotrope of carbon 104.

[0170] In some examples, the or each through-hole 102 is within an outer perimeter of the allotrope of carbon 104, when viewed orthogonally to the plane or lateral extent of the allotrope of carbon 104.

[0171] Any of the features relating to step (III) may be combined with any other features of the method. For example, any of the features relation to step (III) may be combined with any of the above combinations.[0172| For example, the method may comprise the steps of:(I) providing a carbon precursor 101;P20025562(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104,(III) irradiating a portion 103’ of the outer surface of the carbon precursor 101 with a laser beam, thereby to form a through-hole 102 in the carbon precursor 101, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally wherein the laser beam in step (II) has: a scanning speed of from about 150 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C, optionally wherein the through-hole 102 has a diameter of from about 5 pm to about 200 pm, optionally from about 30 pm to about 100 pm.Allotrope of carbon

[0173] The present inventors have found that the allotrope of carbon 104 provides for an aerosol generator which is particularly effective in non-combustible aerosol provision systems. The allotrope of carbon 104 may be considered as providing a carbonaceous surface which can distribute and generate aerosol from the aerosol-generating material in use. Without wishing to be bound by theory, it is believed that where the allotrope of carbon 104 is heated to temperatures for generating aerosol from the aerosol-generating material, the carbonaceous surface may have a high surface free energy and therefore a high wettability (e.g. a low contact angle). In this way, where the allotrope of carbon 104 is heated to temperatures for generating aerosol from the aerosol-generating material, a thin layer of aerosol-generating material may be evenly distributed across the carbonaceous surface of the allotrope of carbon 104 and efficiently aerosolised. Moreover, the allotrope of carbon 104 has a high power density and a low thermal mass, and a small volume of the aerosol-generating material can be thinly formed across a given surface area of the allotrope of carbon 104, relative to materials having a surface across which aerosol-generating material cannot be as thinly formed. This provides for efficient transfer of energy to the aerosol-generating material in use.10174] The allotrope of carbon 104 may be formed as a foam. It will be understood that “allotrope of carbon formed as a foam” means the allotrope of carbon per se is a foam. The foam may comprise a foam structure and a plurality of cells. It will be understood that the allotrope of carbon 104 forms theP20025562 foam structure, and that the foam structure defines the plurality of cells. The foam structure may define the plurality of cells. A plurality of the cells may be interconnected. The foam may be an opencell foam, such as a reticulated foam. It will be understood that the foam is a solid foam (e.g. at least from 20°C to 350°C, at 101325 Pa). The allotrope of carbon 104 may comprise a capillary structure. For example, the foam may comprise a capillary structure.|0175] It has been found that the allotrope of carbon 104 formed as a foam provides for a particularly effective aerosol generator 100. Without wishing to be bound by theory, it is believed that upon the formation of hot spots (localised areas of increased temperature, which may occur when part of a heated aerosol generator dries out in use), the foam (which may have a high thermal conductivity and a high electrical conductivity) can effectively dissipate heat, reduce temperature variation, and reduce the severity of the hot spots. In turn, the aerosol generator 100 can be operated at high power levels with a reduced risk of hot spots causing damage to the aerosol generator. Furthermore, the foam may be compliant to thermal expansion in use. As such, the foam may be resistant to heat-induced degradation in use. It also has been found that the foam can facilitate a reduced battery throughput and / or an extended battery life. Additionally, it has been found that the foam can provide for reduced battery size requirements and thus improved packaging efficiency, e.g. in terms of cost and space requirements. Further, the foam can facilitate rapid volatilisation of aerosol-generating material, which may enhance user experience by reducing the time to generate aerosol in response to a first inhalation (“first puff’) by a user. Moreover, the foam can facilitate consistency between respective inhalations by a user (“puff to puff consistency”). The use of the foam may also provide for certain user experience advantages associated with conventional factory made cigarettes.

[0176] Where the allotrope of carbon 104 is formed as a foam, the foam may comprise multiple layers. Each layer may comprise or consist of carbon atoms arranged in a hexagonal lattice structure, such as a honeycomb lattice structure.

[0177] Where the allotrope of carbon 104 is formed as a foam, the allotrope of carbon 104 may be referred to as a “carbon foam”.

[0178] It will be understood that the carbon foam includes, for example, graphite foam, graphene foam, or any other carbon-based foam.

[0179] It will be understood that various methods may be used to make the foam, including (but not limited to) arc discharge, laser ablation, laser induction, laser-induced pyrolysis, high-pressure carbon monoxide disproportionation, and chemical vapour deposition.

[0180] In some examples, the allotrope of carbon 104 comprises carbon structured so as to contain a plurality of carbon to carbon bonds lying in the same plane. For example, the allotrope of carbon 104P20025562 may comprise graphite. Where the allotrope of carbon 104 comprises graphite, the allotrope of carbon 104 comprises a plurality of stacked layers of carbon atoms, the carbon atoms of each layer being bonded to three adjacent carbon atoms in the layer, with each bond lying in the same plane so as to form a hexagonal lattice structure. Non-covalent bonding exists between the stacked layers. Accordingly, graphite includes multiple stacked layers of carbon, in which the layers of carbon are parallel relative to each other. There are two forms of graphite: alpha graphite, in which the layers are ABA stacked; and beta graphite, in which the layers are ABC stacked.

[0181] In some examples, the allotrope of carbon 104 comprises graphene. For example, the allotrope of carbon 104 may be graphene. Where the allotrope of carbon 104 is (or comprises) graphene, a single layer of carbon atoms, i.e. a one-atom thick layer of carbon, are arranged such that the carbon atoms form a hexagonal lattice structure. The present inventors have found that graphene provides for an effective aerosol generator. Advantageously, upon the formation of hot spots (localised areas of increased temperature, which may occur when part of a heated aerosol generator dries out in use), the high thermal conductivity and electrical conductivity of graphene is such that the graphene can effectively dissipate heat, reduce temperature variation, and reduce the severity of the hot spots. In turn, the aerosol generator 100 can be operated at high power levels with a reduced risk of hot spots causing damage to the aerosol generator. Furthermore, graphene may be elastic and therefore compliant to thermal expansion (e.g. of the electrically insulating substrate; discussed below) in use. Therefore, the aerosol generator 100 may be resistant to degradation due to a difference in thermal coefficient of expansion of the graphene and the electrically insulating substrate (for example). It also has been found that the use of graphene can provide for a reduced battery throughput and thus an extended battery life. Additionally, the use of graphene can provide for reduced battery size requirements and thus improved packaging efficiency, e.g. in terms of cost and space requirements. Further, the use of graphene can facilitate rapid volatilisation of aerosol-generating material, which may enhance user experience by reducing the time to generate aerosol in response to a first inhalation (“first puff’) by a user. Moreover, the use of graphene can facilitate consistency between respective inhalations by a user (“puff to puff consistency”). The use of graphene may also provide for certain user experience advantages associated with conventional factory made cigarettes.[01821 Where the allotrope of carbon 104 comprises graphene, more than one layer of graphene may be present. Where more than one layer of graphene is present, at least two of the layers of graphene may be non-parallel relative to each other. By “non-parallel”, it is meant that an imaginary plane through one layer of graphene (or an imaginary plane of best-fit through a non-planer layer of graphene), is non-parallel relative to an imaginary plane through another layer of graphene (or an imaginary plane of best-fit through the another non-planar layer of graphene). In use, the layers of graphene are electrically connected to form a current path. By providing non-parallel layers ofP20025562 graphene, a porous graphene structure can be provided. The combination of porosity and the low surface energy of graphene at typical aerosolisation temperatures is such that aerosol-generating material can be effectively distributed across not only the outermost surface of the graphene, but also the bulk structure of the graphene. In effect, aerosol-generating material can be provided in intimate contact with an increased surface area of heated material, provided by the graphene layers. This provides for efficient and effective aerosolisation performance. For example, at least three, at least four, at least five, at least six, at least eight, or at least ten of the layers of graphene may be nonparallel relative to each other. Where more than one layer of graphene is present, at least two of the layers of graphene may be parallel relative to each other. For example, the allotrope of carbon 104 may be bilayer graphene.10183] Where the allotrope of carbon 104 comprises graphene, the allotrope of carbon 104 (e.g. the one or more layers of graphene) may comprise or be in the form of three dimensional graphene (which may be referred to as porous graphene or laser-induced graphene (LIG)). Three dimensional graphene may be considered as one or more graphene sheets (or layers) folded back (e.g. on one another) to form a three-dimensional structure. Without wishing to be bound by theory, it is believed the interatomic bonds in three dimensional graphene are formed between predominantly sp2- hybridised orbitals and the predominant local coordination of carbon atoms in three dimensional graphene is similar to that in two dimensional graphene, such that two dimensional and three dimensional graphene may have similar electronic properties. Graphene foam (described below) may be considered an example of three dimensional graphene.

[0184] In examples comprising one or more layers of graphene, the layer or layers may be provided in various forms. For example, the one or more layers of graphene may be formed as a plurality of three-dimensional structures. The three-dimensional graphene structures may be selected from cubes, cuboids, cones, cylinders (e.g. tubes), spheres, pyramids, and / or prisms. It will be understood that various methods may be used to produce three-dimensional graphene structures, including (but not limited to) arc discharge, laser ablation, high-pressure carbon monoxide disproportionation, and chemical vapour deposition.|0185] In some preferred examples, the allotrope of carbon 104 is porous.|0186] In some preferred examples, the allotrope of carbon 104 comprises disordered graphite and / or amorphous carbon. In some preferred examples, the allotrope of carbon 104 is selected from the group comprising disordered graphite, amorphous carbon, or a combination thereof. In some preferred examples, the allotrope of carbon 104 comprises disordered graphite and / or amorphous carbon and / or nanocrystalline graphite. In some preferred examples, the allotrope of carbon 104 is selected from theP20025562 group comprising disordered graphite, amorphous carbon, nanocrystalline graphite, or a combination thereof

[0187] A Raman spectrum of the allotrope of carbon 104 comprises a G band, and a D band. The Raman spectrum of the allotrope of carbon 104 also comprises a 2D band.

[0188] In some examples, the Raman spectrum of the allotrope of carbon 104 comprises a G band peak within a Raman shift range of about 1500 cm'1to about 1650 cm1. In such embodiments Raman spectrum of the allotrope of carbon 104 may comprise a D band peak within a Raman shift range of from about 1250 cm'1to about 1400 cm1. In such examples the Raman spectrum of the allotrope of carbon 104 may comprise a 2D band peak within a Raman shift range of from about 2600 cm'1to about 2750 cm1.|0189] In some examples, the Raman spectrum of the allotrope of carbon 104 comprises a G band peak within a Raman shift range of about 1550 cm'1to about 1590 cm1. In such examples the Raman spectrum of the allotrope of carbon 104 may comprise a D band peak within a Raman shift range of from about 1310 cm'1to about 1340 cm1. In such examples the Raman spectrum of the allotrope of carbon 104 may comprise a 2D band peak within a Raman shift range of from about 2620 cm'1to about 2680 cm'1.[0190| A ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.8 to about 2. The ratio ID / IG may be from about 0.9 to about 1.9. The ratio ID / IG may be from about 1 to about 1.8.

[0191] The ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.2 to about 2. The ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.2 to about 1.6. The ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.2 to about 1.4. The ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.3 to about 1.2. The ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.4 to about 0.8. The ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak may be from about 0.4 to about 0.6.

[0192] The G band peak may have a full width at half maximum (FWHM) of at from about 30 cm'1to about 100 cm1. The G band peak may have a FWHM of from about 30 cm'1to about 70 cm1.

[0193] The 2D band may follow a Gaussian curve model or a Lorentzian curve model.

[0194] Any of the above features relating to the Raman spectrum may be combined. In some examples, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, whereinP20025562 a G band peak is within a Raman shift range of about 1500 cm'1to about 1650 cm1, and a D band peak is within a Raman shift range of from about 1250 cm'1to about 1400 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.8 to about 2. In some embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 1 to about 1.8.[0195| In some preferred embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.2 to about 2. In some preferred embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.2 to about 1.6. In some preferred embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.2 to about 1.4. In some preferred embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.3 to about 1.2. In some preferred embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.4 to about 0.8. In some preferred embodiments, a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.4 to about 0.6.P20025562

[0196] Herein, the Raman spectrum may be measured using Raman microspectroscopy. Herein, the Raman microspectroscopy may be performed using a laser wavelength of 638 nm. Herein, the Raman microspectroscopy may be performed using a grating having 1800 grooves / mm. Herein, the Raman microspectroscopy may be performed with a laser power of 10.9 mW. Herein, the Raman microspectroscopy may be performed using an acquisition time of 5 seconds. Herein, the Raman microspectroscopy may be performed using 20 accumulations. Herein, the Raman microspectroscopy may be performed with a confocal pinhole of 300 pm. Herein, the Raman microspectroscopy may be performed at a wavelength range of from about 1000 cm'1to about 3000 cm1. Herein, the Raman microspectroscopy may be performed with a microscope objective of 5 Ox LWD (long working distance) and 0.8 NA (numerical aperture). Herein, the Raman microspectroscopy may be performed using a Horiba Xplora Plus Raman Microspectrometer. Herein, the Raman microspectroscopy may be performed at 21 °C. Herein, the allotrope of carbon 104 subjected to the Raman microspectroscopy may be unused. That is, the allotrope of carbon 104 has not been used to generate aerosol and / or has not been heated to typical aerosolisation temperatures (post-manufacture of the allotrope of carbon 104).

[0197] It will be understood that the allotrope of carbon 104 is thermally conductive. It will be understood that the allotrope of carbon 104 is electrically conductive.

[0198] The allotrope of carbon 104 may have a thermal conductivity of from 100 Wm 'K'1to 5500 Wm 'K1. The allotrope of carbon 104 may have a thermal conductivity of from 100 Wm 'K'1to 4000Wm 'K1. The allotrope of carbon 104 may have a thermal conductivity of from 100 Wm 'K'1to 2000Wm 'K1. The allotrope of carbon 104 may have a thermal conductivity of from 150 Wm 'K'1to 1000 Wm 'K1. The allotrope of carbon 104 may have a thermal conductivity of from 180 Wm 'K'1to 700Wm 'K1. The allotrope of carbon 104 may have a thermal conductivity of from 200 Wm 'K'1to 500Wm 'K1.

[0199] The allotrope of carbon 104 may have an electrical conductivity of from 1 Sm1to 2.5 x 106Sm1. The allotrope of carbon 104 may have an electrical conductivity of from 100 Sm1to 1.0 x 106Sm1. The allotrope of carbon 104 may have an electrical conductivity of from 200 Sm1to 100000Sm1. The allotrope of carbon 104 may have an electrical conductivity of from 400 Sm1to 50000 Sm"\ The allotrope of carbon 104 may have an electrical conductivity of from 500 Sm1to 10000 Sm1. The allotrope of carbon 104 may have an electrical conductivity of from 600 Sm1to 5000 Sm1. The allotrope of carbon 104 may have an electrical conductivity of from 800 Sm1to 3000 Sm1. The allotrope of carbon 104 may have an electrical conductivity of from 900 Sm1to 1300 Sm1.[0200| The allotrope of carbon 104 may have a thermal conductivity of from 200 Wm 'K'1to 500Wnf'K'1and an electrical conductivity of from 900 Sm1to 1300 Sm1. For example, the allotrope ofP20025562 carbon 104 may have a thermal conductivity of from 200 Wm ' h to 500 Wm'1K'1and an electrical conductivity of from 900 Sm1to 1300 Sm1.

[0201] Features relating to the allotrope of carbon 104 may be combined with any other features of the method. For example, any of the features relating to the allotrope of carbon 104 may be combined with any of the above combinations.

[0202] For example, the method may comprise the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally wherein the laser beam in step (II) has: a scanning speed of from about 150 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C, optionally wherein the allotrope of carbon 104 is porous, optionally wherein the allotrope of carbon 104 comprises disordered graphite and / or amorphous carbon, optionally wherein a Raman spectrum of the allotrope of carbon 104 comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1550 cm'1to about 1590 cm1, and a D band peak is within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.2 to about 2, such as from about 0.4 to 0.8, such as from about 1 to 1.8.Form of the allotrope of carbon

[0203] The allotrope of carbon 104 may take various forms.P20025562

[0204] In some examples, the allotrope of carbon takes a substantially rectangular form (e.g. when viewed from above, e.g. orthogonally to the lateral extent of the carbon precursor 101).

[0205] In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 6 mm. In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 5 mm. In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 4 mm. In some examples, the allotrope of carbon 104 has a length of from about 1 mm to about 3 mm. In some examples, the allotrope of carbon 104 has a length of from about 1.3 mm to about 2 mm. In any of these examples, the allotrope of carbon 104 may take a substantially rectangular form (e.g. when viewed from above, e.g. orthogonally to the lateral extent of the carbon precursor 101).

[0206] In some examples, the allotrope of carbon 104 has a width of from about 0.5 mm to about 6 mm. In some examples, the allotrope of carbon 104 has a width of from about 0.5 mm to about 5 mm. In some examples, the allotrope of carbon 104 has a width of from about 0.5 mm to about 4 mm. In some examples, the allotrope of carbon 104 has a width of from about 1 mm to about 3 mm. In some examples, the allotrope of carbon 104 has a width of from about 1.3 mm to about 2 mm. In any of these examples, the allotrope of carbon 104 may take a substantially rectangular form (e.g. when viewed from above, e.g. orthogonally to the lateral extent of the carbon precursor 101).

[0207] In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 6 mm and a width of from about 0.5 mm to about 6 mm. In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 5 mm and a width of from about 0.5 mm to about 5 mm. In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 4 mm and a width of from about 0.5 mm to about 4 mm. In some examples, the allotrope of carbon 104 has a length of from about 1 mm to about 3 mm and a width of from about 1 mm to about 3 mm. In some examples, the allotrope of carbon 104 has a length of from about 1.3 mm to about 2 mm and a width of from about 1.3 mm to about 2 mm. In any of these examples, the allotrope of carbon 104 may take a substantially rectangular form (e.g. when viewed from above, e.g. orthogonally to the lateral extent of the carbon precursor 101).

[0208] In some examples, the allotrope of carbon 104 has a length of from about 0.5 mm to about 6 mm. In some examples, the allotrope of carbon 104 has a length of from about 1 mm to about 4 mm. In some examples, the irradiated portion has a length of from about 2 mm to about 3.2 mm. In some examples, the allotrope of carbon 104 has a length of from about 2.2 mm to about 3 mm. In some examples, the allotrope of carbon 104 has a length of from about 2.4 mm to about 2.8 mm. In any of these examples, the allotrope of carbon 104 may take a rectangular shape.P20025562

[0209] In some examples, the allotrope of carbon 104 has a width of from about 0.5 mm to about 6 mm. In some examples, the allotrope of carbon 104 has a width of from about 1 mm to about 4 mm. In some examples, the allotrope of carbon 104 has a width of from about 1.4 mm to about 2.6 mm. In some examples, the allotrope of carbon 104 has a width of from about 1.6 mm to about 2.2 mm. In some examples, the allotrope of carbon 104 has a width of from about 1.7 mm to about 2.1 mm. In any of these examples, the allotrope of carbon 104 may take a rectangular shape.

[0210] In some examples, the allotrope of carbon 104 has a length from about 0.5 mm to about 6 mm and a width of from about 0.5 mm to about 6 mm. In some examples, the allotrope of carbon 104 has a length from about 1 mm to about 4 mm and a width of from about 0.5 mm to about 5 mm. In some examples, the allotrope of carbon 104 has a length from about 2 mm to about 3.2 mm and a width of from about 1.4 mm to about 2.6 mm. In some examples, the allotrope of carbon 104 has a length from about 2.2 mm to about 3 mm and a width of from about 1.6 mm to about 2.2 mm. In some examples, the allotrope of carbon 104 has a length from about 2.4 mm to about 2.8 mm and a width of from about 1.7 mm to about 2.1 mm. In any of these examples, the allotrope of carbon 104 may take a rectangular form.

[0211] Features relating to the form of the allotrope of carbon 104 may be combined with any other features of the method. For example, any of the features relating to the form of the allotrope of carbon 104 may be combined with any of the above combinations10212] For example, the method may comprise the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally wherein the laser beam in step (II) has: a scanning speed of from about 140 mm / s to about 450 mm / s, optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C,P20025562 optionally wherein the allotrope of carbon 104 has a length from about 2 mm to about 3.2 mm and a width of from about 1.4 mm to about 2.6 mm, optionally a length from about 2.2 mm to about 3 mm and a width of from about 1.6 mm to about 2.2 mm, optionally a length from about 2.4 mm to about 2.8 mm and a width of from about 1.7 mm to about 2.1 mm.Aerosol generator

[0213] According to a second aspect of the present disclosure, there is provided an aerosol generator 100 for use as part of a non-combustible aerosol provision system, the aerosol generator 100 comprising an allotrope of carbon 104.10214] The aerosol generator 100 may be obtained and / or obtainable by the method according to the first aspect of the present disclosure.

[0215] For example, the aerosol generator 100 may be obtained and / or obtained by a method comprising the steps of:(I) providing a carbon precursor 101;(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2.

[0216] The method may include any features defined in relation to the method of the first aspect of the present disclosure. For example, the aerosol generator 100 may be obtained and / or obtained by a method comprising the steps of:(I) providing a carbon precursor 101; and(II) irradiating a portion 103 of an outer surface of the carbon precursor 101 with a laser beam, thereby to form an allotrope of carbon 104, wherein in step (II) the laser beam delivers a fluence to the irradiated portion 103 of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2, optionally wherein the laser beam in step (II) has: a scanning speed of from about 150 mm / s to about450 mm / s,P20025562 optionally wherein in the step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C.10217] For example, the allotrope of carbon 104 of the aerosol generator 100 may be as defined herein. For example, the allotrope of carbon 104 may comprise disordered graphite and / or amorphous carbon. For example, a Raman spectrum of the allotrope of carbon 104 may be as described herein.|0218] In some examples, the allotrope of carbon 104 has a thickness of from about 50 pm to about 500 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 50 pm to about300 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 80 pm to about300 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 90 pm to about200 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 100 pm to about150 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 120 pm to about130 pm.

[0219] In some examples, the allotrope of carbon 104 has a thickness of from about 20 pm to about 150 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 30 pm to about120 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 40 pm to about110 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 50 pm to about100 pm.|0220] In some examples, the allotrope of carbon 104 has a thickness of from about 1 pm to about 50 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 1 pm to about 20 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 1 pm to about 10 pm. In some examples, the allotrope of carbon 104 has a thickness of from about 1 pm to about 5 pm.

[0221] In some examples, the allotrope of carbon 104 has athickness of up to about 50 pm. In some examples, the allotrope of carbon 104 has athickness of up to about 40 pm. In some examples, the allotrope of carbon 104 has a thickness of up to about 30 pm. In some examples, the allotrope of carbon 104 has a thickness of up to about 20 pm. In some examples, the allotrope of carbon 104 has a thickness of up to about 5 pm.[0222| The thickness of the allotrope of carbon 104 is understood to refer to the extent of carbon allotrope 104, measured orthogonally to the plane or lateral extent of the allotrope of carbon 104, between opposing outer surfaces of the allotrope of carbon 104. Where the allotrope of carbon 104 includes internal pores, these are effectively ignored for in the measurement of thickness. By way of example, a first example allotrope of carbon and a second example allotrope of carbon which differP20025562 only insofar as the first example allotrope has internal pores and the second example allotrope is non- porous, will have the same thickness. The thickness of the allotrope of carbon 104 may refer to the thickness of a single layer or a multi-layer. Those skilled in the art will be aware of suitable methods for measuring the thickness of the allotrope of carbon 104, e.g. electron microscopy.|0223] In some examples, the allotrope of carbon 104 is substantially planar.

[0224] In some examples, the allotrope of carbon is supported on an electrically insulating substrate. The electrically insulating substrate may be (or correspond to a part of) the carbon precursor 101, which is as defined herein. In this way, the electrically insulating substrate may include any of the features of the carbon precursor 101, as defined herein. For example, the electrically insulating substrate 101 may comprise one or more through-holes 102 extending therethrough.Additional Features10225] The allotrope of carbon 104 may not include metal. Moreover, the aerosol generator 100 may not include metal. For example, the aerosol generator 100 may not include a metal-containing electrical contact. The allotrope of carbon 104 may be connected directly to a power source, without requiring a metal -containing electrical contact as part of the allotrope of carbon 104. In this way, the metal emissions of the aerosol generator 100 may be reduced in use.Article

[0226] According to a third aspect of the present disclosure, there is provided an article for use as part of a non-combustible aerosol provision system, the article comprising: the aerosol generator 100 according to the second aspect of the present disclosure.

[0227] The article may comprise a reservoir for aerosol-generating material.

[0228] The article may comprise a housing.|0229] The reservoir may be provided in the housing.10230] The article may comprise a mouthpiece.|0231] The article may comprise a first group of components. The first group of components may comprise the reservoir, the housing, the aerosol generator, and the mouthpiece (where present). The first group of components may be formed from up to four different materials. The first group of components may be formed from up to three different materials. The first group of components may be formed from up to two different materials. The first group of components may be formed from a single material.P20025562

[0232] In some examples, one of the materials or the material is a polyimide. In some examples, one of the materials or the material is a polyetheretherketone. In some examples, the materials comprise a polyimide and a polyetheretherketone. In some examples, one of the materials is a polyimide and one of the materials is polyetheretherketone.

[0233] The first group of components may be integrally formed.Non-combustible aerosol provision system

[0234] According to a fourth aspect of the present disclosure, there is provided a non-combustible aerosol provision system comprising: the aerosol generator 100 according to the second aspect of the present disclosure; and a power source and / or a controller.

[0235] The non-combustible aerosol provision system may comprise the article according to the third aspect of the present disclosure; and the power source and / or the controller.

[0236] In some examples, the power source is configured to supply electrical power to the article (e.g. to the aerosol generator).

[0237] In some examples, the controller is configured to control the article (e.g. to control the supply of electrical power to the aerosol generator).Experimental[0238| The present inventors prepared example aerosol generators 100 using the method set out below, according to the first aspect of the present disclosure.Allotrope of carbon formation[0239| A first laser was used to irradiate a rectangular area 103 (about 1.9 mm by about 2.6 mm) of the outer surface of a polyimide sheet 101. The polyimide sheet 101 was substantially planar, had a thickness of 125 pm, and made of poly(4,4'-oxydiphenylene-pyromellitimide). The polyimide sheet 101 is commercially available from DuPont under the trade name Kapton® HN. The first laser was a Keyence ML-Z9610: a CO2 laser having 10.6 pm wavelength, 140 pm spot diameter (i.e. the 1 / e2beam diameter), 30 W maximum power). In this regard, the laser beam of the first laser irradiated the rectangular area 103 along a plurality of horizontal straight lines (i.e. raster scanning lines or scanning lines), which lines being arranged side-by-side and together forming a scanning pattern. The respective centre-points (or central axes) of adjacent scanning lines were spaced apart by the beam diameter, i.e. 140 pm. Adjacent scanning lines overlapped to form an overlapped region, wherein theP20025562 overlapped region was subjected to two passes each at about 13.5% of the peak intensity of the laser beam.

[0240] When traversing each of the scanning lines, the laser beam of the first laser moved at a substantially constant speed. The irradiation step by the first laser resulted in the formation of an allotrope of carbon 104 (“allotrope of carbon formation step”) at the irradiated rectangular area 103. Thereby, there was provided an allotrope of carbon 104 on a polyimide substrate 101. The allotrope of carbon 104 may be supported on and / or formed integrally with the polyimide substrate 101. A second laser was used to irradiate around the perimeter of the rectangular area 103, so as to separate a section including the allotrope of carbon 104 and the underlying polyimide substrate 101 on which the allotrope of carbon 104 was supported from the remaining material.

[0021] In some examples, the second laser was used to provide a plurality of through-holes 102 extending through the polyimide substrate 101, each through hole having a diameter of from around 30 pm to around 100 pm. The step of providing the through-holes 102 may occur before or after (preferably before) the allotrope of carbon formation step.[0242| The second laser was a Keyence MD-U1000C: CO2 laser having 355 nm wavelength, 30 pm spot diameter (i.e. the 1 / e2beam diameter), 3 W maximum power.

[0243] The separated section corresponded to an aerosol generator 100 comprising an allotrope of carbon 104 and a polyimide substrate 101.[0244| The above-mentioned method steps were repeated by varying the following parameters of the laser beam of the first laser in the allotrope of carbon formation step: power (varying from 3 W to 31 W) and scanning speed (varying from 50 mm / s to 900 mm / s), to make a plurality of aerosol generators 100.

[0245] In each of the aerosol generators 100, the allotrope of carbon 101 had a length of about 2.6 mm, a width of about 1.9 mm, and was substantially rectangular in form.Test data

[0246] With regard to the allotrope of carbon formation step, the power and the scanning speed of the laser beam of the first laser were used to determine the fluence delivered by the laser beam of the first laser to the area 103. The following formula was used:PowerFluence = — - - - - - -Velocity x beam diameterP20025562 wherein fluence was the amount of energy delivered by the laser beam per unit surface area (J / mm2), power was the power of the laser beam (W), velocity was the scanning speed of the laser beam (mm / s), and beam diameter was the 1 / e2beam diameter of the laser beam.

[0247] Various characteristics of the aerosol generators 100 were determined, including: electrical conductivity, mechanical integrity, and electrical resistance.|0248] Mechanical integrity was determined by visual inspection and inspection using a scanning electron microscope (SEM). Electrical resistance was determined using an ohmmeter having a pair of flat plate electrodes. Each electrode was arranged to span the width of the allotrope of carbon 104 and was arranged at a respective end of the allotrope of carbon 104. The electrodes were arranged in parallel with each other. The ohmmeter was also used to determine electrical conductivity. Alternative means may be used to measure electrical resistance and electrical conductivity.

[0249] The above-mentioned characteristics of the aerosol generators 100 are provided in Fig. 4, in which each cell is representative of an aerosol generator 100 prepared using the above-mentioned method steps, wherein in the allotrope of carbon formation step the laser beam of the first laser had a particular scanning speed and a particular power. For example, the top left cell (ignoring the laser parameter cells) is representative of an aerosol generator 100 prepared wherein in the allotrope of carbon formation step the laser beam of the first laser had a scanning speed of 50 mm / s and a power of 3 W (i.e. 10% of the maximum 30 W power). The cells including “Damaged” correspond to aerosol generators 100 in which the allotrope of carbon 104 was damaged by the laser beam of the first laser in the allotrope of carbon formation step. The cells including “Outrange” correspond to aerosol generators 100 in which the allotrope of carbon 104 had low or no electrical conductivity. The cells filled with a diagonal line pattern correspond to aerosol generators 100 in which the allotrope of carbon 104 had a higher than desired electrical resistance (i.e. greater than about 60 Ohms). The cells filled with a dotted pattern correspond to aerosol generators 100 in which the allotrope of carbon 104 had a desirable electrical resistance (i.e. from about 1 Ohms to about 60 Ohms).

[0250] For clarity, the following cells include “Damaged”: 20% power at 100 mm / s; 30% power at 100 mm / s; 40% power at 150 mm / s; 50% power at 150 mm / s; 60% power at 250 mm / s. The following cells include “Outrange”: 10% power at 150 mm / s; 20% power at 250 mm / s; 30% power at 400 mm / s; 40% power at 550 mm / s; 50% power at 700 mm / s; 60% power at 800 mm / s.

[0251] Fig. 4 also shows three dashed lines: a first (lower) indicative of a fluence of 0.54 J / mm2; a second (middle) indicative of a fluence of 0.3 J / mm2, and a third (upper) indicative of a fluence of 0.14 J / mm2.P20025562

[0252] The present inventors identified that using a fluence of the laser beam of the first laser in the allotrope of carbon formation step of less than about 0.14 J / mm2resulted in the allotrope of carbon 104 having low or no electrical conductivity. The present inventors also identified that using a fluence of the laser beam of the first laser in the allotrope of carbon formation step of greater than about 0.54 J / mm2resulted in damage to the allotrope of carbon 104 (e.g. cracks and / or flaky). The present inventors found that using a fluence of the laser beam of the first laser in the allotrope of carbon formation step of from about 0. 14 J / mm2to about 0.54 J / mm2resulted in an allotrope of carbon 104 having desirable electrically conductivity, electrical resistance, and mechanical robustness.[0253| Figs. 5 A to 5 C shows scanning electron microscope (SEM) images of the allotrope of carbon 104 of the aerosol generators 100 samples prepared wherein the laser beam of the first laser in the allotrope of carbon formation step had a power of 6 W (20% of max power) and a scanning speed ranging from 50 mm / s to 300 mm / s. In particular, in each of Figs. 5 A to 5C, the upper two images are SEM images in plan-view of the aerosol generator 100, facing the allotrope of carbon 104, and the lower two images are SEM images in cross-sectional view, in which the cutting plane extends through the thickness of the aerosol generator 100.10254] As shown in Fig. 5A, when the scanning rate was 50 mm / s or 100 mm / s, and the fluence was greater than about 0.54 J / mm2, structural damage in the allotrope of carbon 104 was observed. Without being bound by theory, this was believed to be due to gas formation (“outgassing”) in the polyimide structure. As shown in Fig. 5C, where the scanning rate was 250 mm / s or 300 mm / s, and the fluence was less than about 0.14 J / mm2, gaps or discontinuity in the structure allotrope of carbon 104 was observed. Without being bound by theory, this was believed to be because the allotrope of carbon 104 had not suitably or completely formed. As shown in Fig. 5B, where the scanning rate was 150 mm / s or 200 mm / s, such that the fluence was from about 0. 14 J / mm2to about 0.54 J / mm2, greater structural continuity of the allotrope of carbon 104 was observed.

[0255] Fig. 6 shows a plot of temperature reached by the outer surface of the area 103 in the allotrope of carbon formation step (y-axis) against the fluence delivered by the laser beam of the first laser to the area 103 in the allotrope of carbon formation step (x-axis), in respect of the allotrope of carbon 104 of aerosol generator 100 samples prepared as outlined above. Six data sets are shown corresponding to different powers of the laser beam of the first laser in the allotrope of carbon formation step: 6 W (black square points; rightmost curve), 9 W (diamond points; first left curve from 6 W curve), 12 W (light grey square points; second left curve from 6 W curve); 15 W (grey square points; third left curve from 6 W curve), 18 W (light grey triangle points; fourth left curve from 6 W curve) and 21 W (triangular points; leftmost curve). It was found that when the area 103 reached a temperature of above about 3300°C, the allotrope of carbon 104 was damaged. It was found that when the area 103 reached a temperature of less than about 1350°C, the allotrope of carbon 104 showedP20025562 litle or no electrical conductivity. In some samples, it was found that when the area 103 reached a temperature of from about 1350°C to about 3300°C, the allotrope of carbon 104 was electrically conductive and undamaged by the laser beam.Raman spectroscopy

[0256] The present inventors have analysed various allotrope of carbon 104 samples using Raman microspectroscopy.

[0257] Each of the allotrope of carbon 104 samples was prepared as outlined above, under “Experimental - Method of manufacturing aerosol generators”.

[0258] Without wishing to be bound by theory, Raman spectroscopy is considered as a nondestructive vibrational spectroscopic technique that utilises a laser to excite the bonds within a sample (e.g. carbon) and interprets the inelastic scatering of the bond vibrations as a relative Raman shift.The inelastic scatering from interaction with the sample produces a relative Raman shifts and thereby a spectrum that can be utilised to interpret the characteristics and / or identity of the sample. For characterisation of the allotrope of carbon samples, one can investigate the peak position of the D band which is typically observed at around 1329 cm1, the G band which is typically observed at around 1579 cm1, and the 2D band which is typically observed at around 2630 cm1. The D band can be referred to as the “disorder band” and is an indication of sp3hybridization of carbon within the sample. The G band can be referred to as the “graphene band” and is utilised to determine the sp2hybridization of the carbon structure within the sample. For example, the Raman spectrum of a pristine graphene sample would typically include a high intensity, narrow G band and no D band. The Raman spectrum of a graphite sample would typically include a G band and a D band, with the D band being lower in intensity than the G band. The ID / IG ratio can be utilized by determining the counts of the intensity (a.u.) of the D band peak (ID) to the counts of the intensity of the G band peak (IG) and can be used to determine the allotrope of carbon present within the sample. The 2D band can also be utilized by interpreting the area of the curve and peak position to determine the morphology of the allotrope. For example, crystalline graphite would typically exhibit a sharp and narrow peak curve that would follow a Lorentzian curve fit model while the 2D band of a sample including amorphous carbon would typically exhibit broader and flater band which follows a Gaussian curve fit model.The full width at half maximum (FWHM) of a peak also can be used to determine crystallinity within a sample. The FWHM is measured by determining the width of the peak in question at half the total intensity of the sample.10259] The Raman microspectroscopy involved measuring a Raman spectrum of each of the samples 104 using a Horiba Xplora Plus Raman Microspectrometer and the following parameters:P20025562 a laser wavelength of 638 nm; a grating having 1800 grooves / mm; an acquisition time of 5 seconds;20 accumulations (20 spectra); a laser power of 10.9 mW; a confocal pinhole of 300 pm; and a wavelength range of from about 1000 cm'1to about 3000 cm1.|0260] The Raman microspectroscopy was performed at 21 °C.

[0261] The allotrope of carbon samples subjected to Raman microspectroscopy were unused.[0262| The Raman spectrum of each of the allotrope of carbon 104 samples comprised a G band, and D band, wherein a G band peak was within a Raman shift range of about 1550 cm'1to about 1590 cm' \ and a D band peak was within a Raman shift range of from about 1310 cm'1to about 1340 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak was from 1 to 1.8. The Raman spectrum of each of the allotrope of carbon 104 samples comprised a 2D band peak within a Raman shift range of from about 2620 cm'1to about 2680 cm1. In the Raman spectrum of each of the allotrope of carbon 104 samples, the G band peak had a full width at half maximum (FWHM) of from about 45 cm'1to about 62 cm1. In the Raman spectrum of each of the allotrope of carbon 104 samples, the 2D band typically followed a Lorentzian curve fit model.

[0263] The Raman spectrum of each of the allotrope of carbon 104 samples indicated that the samples included disordered graphite, amorphous carbon, or a combination thereof.

[0264] Fig. 7 shows the Raman spectrum of one of the allotrope of carbon 104 samples. The sample was unused. As shown in Fig. 7, a G band peak was observed at about 1573 cm1, a D band peak was observed at about 1320 cm'1, and a 2D band peak was observed at about 2630 cm1. The ratio IG / ID of the intensity IG of the G band peak to the intensity ID of the D band peak was about 1.6. The G band peak had a FWHM of about 62 cm1. The 2D band followed a Lorentzian curve fit model.

[0265] Fig. 9 shows the Raman spectra of (another) one of the allotrope of carbon 104 samples, the SEM image of which sample being shown in Fig. 8. The sample was unused. Fig. 9 shows a first spectrum (1) taken at point (1) in Fig. 8; and a second spectrum (2) taken at point (2) in Fig. 8. Point (1) corresponded to the centre-point of a scanning line, at which the portion 103 was subjected to aP20025562 single pass of the laser beam. Point (2) corresponded to an overlapping region between adjacent scanning lines, at which the portion 103 was subjected to two passes by the laser beam, each at about 13.5% of the peak laser beam intensity. In each spectrum, a G band peak was observed at about 1573 cm1, a D band peak was observed at about 1320 cm1, and a 2D band peak was observed at about 2630 cm1. In the spectrum (1), the ratio IG / ID of the intensity IG of the G band peak to the intensity ID of the D band peak was about 0.5. In the spectrum (2), the ratio IG / ID of the intensity IG of the G band peak to the intensity ID of the D band peak was about 0.9.

[0266] The present inventors have found that the allotrope of carbon 104 comprising disordered graphite, amorphous carbon, nanocrystalline graphite, or a combination thereof provided for a particularly effective aerosol generator 100. Such allotropes of carbon 104 were found to effectively dissipate heat, reduce temperature variation, and reduce the severity of any hot spots. Such allotropes of carbon 104 exhibited a low electrical resistance (and high electrical conductivity) that was particularly suited to use in non-combustible aerosol provision systems. Such allotropes of carbon 104 also facilitated effective liquid distribution, e.g. across the surface of and / or within the allotrope of carbon 104.

[0267] Any aspect of the present disclosure may be defined in relation to any of the other aspects of the present disclosure. For example, one aspect of the present disclosure may include any of the features of any other aspect of the present disclosure and / or the features of one aspect of the present disclosure may be as defined in relation to the features of any other aspect of the present disclosure.]0268] The figures herein are schematic and not drawn to scale. The various examples described herein are presented only to assist in understanding and teaching the claimed features. These examples are provided as a representative sample of examples only, and are not exhaustive and / or exclusive. It is to be understood that advantages, examples, functions, features, structures, and / or other aspects described herein are not to be considered limitations on the scope of the invention as defined by the claims or limitations on equivalents to the claims, and that other examples may be utilised and modifications may be made without departing from the scope of the claimed invention. Various examples of the claimed invention may suitably comprise, consist of, or consist essentially of, appropriate combinations of the disclosed elements, components, features, parts, steps, means, etc., other than those specifically described herein. In addition, this disclosure may include other inventions not presently claimed, but which may be claimed in future.

Claims

P20025562CLAIMS1. A method of manufacturing an aerosol generator for use as part of a non-combustible aerosol provision system, the method comprising the steps of:(I) providing a carbon precursor;(II) irradiating a portion of an outer surface of the carbon precursor with a laser beam, thereby to form an allotrope of carbon, wherein in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0.10 J / mm2to about 0.80 J / mm2.

2. The method according to claim 1, wherein in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0. 14 J / mm2to about 0.54 J / mm2.

3. The method according to claim 1 or 2, wherein in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0.25 J / mm2to about 0.35 J / mm2.

4. The method according to any one of claims 1 to 3, wherein in step (II) the laser beam delivers a fluence to the irradiated portion of the outer surface of from about 0.30 J / mm2to about 0.35 J / mm2.

5. The method according to any one of claims 1 to 4, wherein in step (II) the laser beam has a scanning speed of from about 100 mm / s to about 450 mm / s, such as from about 150 mm / s to about 450 mm / s.

6. The method according to any one of claims 1 to 5, wherein in step (II) the laser beam has a power of from about 1 W to about 30 W, optionally from about 3 W to about 21 W.

7. The method according to any one of claims 1 to 6, wherein in step (II) the irradiating of the portion of the outer surface causes the portion of the outer surface to reach a temperature of from about 1000°C to about 3500°C, optionally from about 1350°C to about 3300°C, optionally from about 1500°C to about 3000°C, optionally from about 1700°C to about 2600°C.

8. The method according to any one of claims 1 to 7, wherein in step (II) the laser beam has a wavelength of from 8 pm to 16 pm, optionally from 9 pm to 14 pm, optionally from 10 pm to 12 pm, optionally wherein in step (II) the laser beam is generated by a carbon dioxide laser.P200255629. The method according to any one of claims 1 to 8, the method comprising the step of:(III) irradiating a portion of an outer surface of the carbon precursor with a laser beam, thereby to form a through-hole in the carbon precursor, optionally wherein an opening of the through-hole is adjacent to the allotrope of carbon.

10. The method according to claim 9, wherein an opening of the through-hole is partially or completely covered by the allotrope of carbon, optionally wherein the allotrope of carbon at least partially extends into the through-hole.

11. The method according to claim 9 or 10, wherein the through-hole has a diameter of from 5 pm to 200 pm, optionally from 30 pm to 100 pm.

12. The method according to any one of claims 1 to 11, wherein the outer surface of the carbon precursor comprises a first surface and a second surface which is opposite from the first surface, wherein the portion of the outer surface is the first surface.

13. The method according to any one of claims 1 to 12, wherein the carbon precursor is substantially planar.

14. The method according to any one of claims 1 to 13, wherein the carbon precursor has a thickness of from 50 pm to 300 pm, optionally from about 90 pm to about 200 pm, optionally from about 100 pm to about 150 pm, optionally from about 120 pm to about 130 pm.

15. The method according to any one of claims 1 to 14, wherein the allotrope of carbon has a has length of from about 2 mm to about 3 mm, a width of from about 1.5 mm to about 2.5 mm.

16. The method according to any one of claims 1 to 15, wherein the allotrope of carbon has an electrical resistance of from about 10 ohms to about 60 ohms, such as from about 40 ohms to about 60 ohms.

17. The method according to any one of claims 1 to 16, wherein the carbon precursor is made of polyimide.

18. The method according to any one of claims 1 to 17, wherein the allotrope of carbon comprises disordered graphite and / or amorphous carbon and / or nanocrystalline graphite.P2002556219. The method according to any one of claims 1 to 18, wherein a Raman spectrum of the allotrope of carbon comprises a G band, and D band, wherein a G band peak is within a Raman shift range of about 1500 cm'1to about 1650 cm1, and a D band peak is within a Raman shift range of from about 1250 cm'1to about 1400 cm1, wherein a ratio ID / IG of the intensity ID of the D band peak to the intensity IG of the G band peak is from about 0.2 to about 2, optionally from about 0.2 to about 1.6, optionally from about 0.4 to about 0.8, optionally from about 0.4 to about 0.6.

20. The method according to any one of claims 1 to 19, wherein in step (II) the laser beam irradiates the portion of the outer surface along one or more scanning lines, optionally wherein adjacent scanning lines are contiguous with each other or overlap each other.

21. The method according to claim 20, wherein the scanning lines form a scanning pattern which superposes the portion of the outer surface.

22. The method according to claim 20 or 21, wherein in step (II) adjacent scanning lines are overlapping, such that the region of overlap is subjected to at least about 50% of the peak intensity of the laser beam.

23. An aerosol generator for use as part of a non-combustible aerosol provision system, the aerosol generator comprising an allotrope of carbon, wherein aerosol generator is obtained and / or obtainable by the method according to any one of claims 1 to 22.

24. An article for use as part of a non-combustible aerosol provision system, the article comprising: the aerosol generator according to claim 23; and a reservoir for aerosol-generating material.

25. A non-combustible aerosol provision system comprising: the article according to claim 24; and a power source and / or a controller.

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